CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of United States provisional application serial no. 63/007,071, filed 8 April 2020. The entire contents of this applications hereby incorporated by reference as if fully set forth herein.

BACKGROUND

1. Field of the Invention

[0002] The invention relates to the field of medicine, and in particular to a method of reducing fat in the liver of a subject. The method involves administering to the subject TAK- 448 or any salt thereof; a conservative variant of TAK-448 or any salt thereof; kisspeptin-10 or any salt thereof; or a conservative variant of kisspeptin-10 or any salt thereof.

2. Background of the Invention

[0003] The liver is the principal organ involved in lipid metabolism. Dyslipidemia leads to metabolic disorders such as non-alcoholic fatty liver disease (NAFLD) which has become an increasing public health concern affecting approximately 1 billion individuals worldwide. In the U.S, NAFLD is a national epidemic that affects over 12 million adults and 8 million children, with associated annual medical costs of $103 billion.

[0004] NAFLD is the leading cause of liver disease worldwide. NAFLD is characterized by accumulation of liver fat (steatosis), leading to the generation of cytotoxic lipid oxidation by products which progresses to a chronic inflammatory state with hepatocyte injury, defined as non-alcoholic steatohepatitis (NASH). As the disease advances, a subset of patients will develop fibrosis, cirrhosis and liver failure or hepatocellular carcinoma (HCC). NAFLD/NASH have replaced hepatitis C as the most common indication for liver transplantation in the next decade. Thus, NAFLD encompasses a spectrum of pathological conditions, including steatosis (fatty liver), non-alcoholic steatohepatitis (NASH), and fibrosis and cirrhosis (excessive non-reversible scarring of liver).

[0005] Kisspeptins (KPs), the peptide products of the KISS1 gene, are endogenous ligands for the Kisspeptin 1 receptor (KISS1R), a G-protein coupled receptor. The KP/KISS1R signaling system is expressed both centrally (in the brain) and peripherally, where it plays a major role in reproduction and metabolism. In fact, liver Kissl expression was found to be increased in genetic models of obesity (db/db and ob/ob mice). Although KISS1 and KISS1R are expressed in the liver, a role for hepatic KISS1R signaling in regulating lipogenesis is not known.

[0006] The prevalence of NAFLD mirrors the rise in obesity and type II diabetes, affecting about 100 million Americans. However, medicines used to treat type II diabetes are not approved to treat NAFLD. Apart from weight-loss and bariatric surgery which is beneficial in the early stages of the disease, currently there are no FDA approved drugs to treat NAFLD/NASH. FDA guidance to industry has stated that “the FDA believes that identifying therapies that will slow the progress of, halt, or reverse NASH and NAFLD will address an unmet medical need.” See fda.gov (Dec 2018). As the rates of obesity continue to escalate, NAFLD-related liver disease and mortality will rise in the U.S. The global market of NASH therapeutics and liver cirrhosis drugs market is projected to reach USD18.3B and USD 66.01B, respectively, by 2026.

[0007] Thus, there is a critical need to develop new treatments for NAFLD/NASH.

SUMMARY OF THE INVENTION

[0008] This invention involves repurposing the use of TAK-448 in NAFLD or NASH. In this study, a high-fat diet-induced pre-clinical mouse model of NAFLD was used to demonstrate that a hepatic knock-out of Kisslr promotes steatosis. Moreover, infusion of the KP analog (TAK-448) in obese, wild-type diabetic mice protects against disease progression. Mechanistically, KP signaling was demonstrated to negatively regulate de novo lipogenesis (fat formation) by activating AMP-activated protein kinase (AMPK) and also by promoting the beta-oxidation or breakdown of fat in mitochondria, in addition to suppressing the peroxisome proliferator-activated receptor-g (PPARy) signaling pathway. This study provides direct evidence that both pharmacological and genetic interventions directed at KISS1R can protect against the development of NAFLD and limit its progression to NASH and fibrosis.

[0009] Specifically, the invention relates to a method of treatment or prevention of NAFLD/NASH in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of TAK-448. Preferably, the subject is a NAFLD patient or a NASH patient. Administration may be by any route, but preferably is subcutaneous.

[0010] Certain embodiments of the invention include a method of reducing fat in the liver of a subject in need thereof, comprising administering to the subject a therapeutically effective amount of a compound selected from TAK-448 and any salt thereof; a conservative variant of TAK-448 and any salt thereof; kisspeptin-10 and any salt thereof; and a conservative variant of kisspeptin-10 and any salt thereof. The subject preferably suffers from a fatty liver and/or a condition selected from alcoholism, hepatitis, non-alcoholic fatty liver disease (NALFD), or non-alcoholic steatohepatitis (NASH); most preferably the subject suffers from non-alcoholic fatty liver disease (NALFD) or non-alcoholic steatohepatitis (NASH).

[0011] Some embodiments of the invention relate to a method that further comprises administering to the subject a therapeutic amount of a second compound selected from AKR- 001, aramchol, ASC40, AZD7687, BI089-100, BMS-986036, canagliflozin, cenicriviroc, cilofexor, dapagliflozin, EDP-305, elafibranor, emricasan, EYPOOla, fenofibrate, firsocostat, GR-MD-02, IONIS-DGAT2 _Rx , ipragliflozin, licogliflozin, luseogliflozin, LY3202328, MET409, metformin, MGL-3196, MK-4074, MSDC-0602K, MT-3995, NGM282, nidufexor, PF-05221304, PF-06835919, PF-06865571, PF-06882961, PX-102, PXL770, PXS-5153A, selonsertib, simtuzumab, simaglutide, TERN-101, TERN-201, troifexor, vitamin D, vitamin E, and VK2809.

[0012] The method of administering can be subcutaneous, intravenous, or oral.

BRIEF SUMMARY OF THE DRAWINGS [0013] FIG. 1A through FIG. 1J. TAK-448 reduces fat accumulation in the liver (steatosis) and improves metabolic profile in a pre-clinical mouse model of NAFLD. FIG. 1 A is a histological photograph of hematoxylin and eosin stained mouse livers, where indicated (black arrowheads), showing steatosis (small white areas in liver), and liver lipid staining with Oil Red O, where indicated (gray dots), for control (vehicle, phosphate buffered saline or PBS) and TAK-448-treated mouse livers (5 mice/group) on high fat diet (HFD). TAK-448 treatment reduces HFD-induced liver steatosis compared to littermate controls on HFD. FIG. IB through FIG. 1G show the beneficial effect of TAK-448 in lowering endpoint liver triglycerides (TGs) (FIG. IB), endpoint blood triglycerides (FIG. 1C), blood free fatty acids (FFA) (FIG. ID), end point body weight (FIG. IE), and peripheral fat accumulation in animals (FIG. IF (epididymal white adipose tissue or eWAT) and FIG. 1G (inguinal white adipose tissue or iWAT)). Endpoint is defined as post euthanasia of mice. FIG. 1H through FIG. 1J show that TAK-448 treatment prevented a rise in fasting glucose (FIG. 1H), prevented glucose intolerance (improving diabetes) as determined using a glucose tolerance test (GTT) (FIG. II), and prevented insulin resistance using insulin tolerance test (ITT) (FIG. 1J).

[0014] FIG. 2A through FIG. 2C. FIG. 2A and FIG. 2B show the body weights (FIG. 2A) and fasting glucose (FIG. 2B) in wild-type C57BL6/J mice prior to treatment with Vehicle (VEH, PBS) or Takeda-448 (TAK, 0.3 nmol/h). FIG. 2C shows no difference in food intake in mice treated with TAK or controls, as measured by Clinical Laboratory Animal Monitoring System (CLAMS), 4 weeks post treatment; 10 weeks on RD/HFD; 5 mice/group. Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05 compared to VEH controls.

[0015] FIG. 3A through FIG. 3C show serum enzyme alanine aminotransferase (ALT) levels, marker for fatty liver (FIG. 3A), serum cholesterol (FIG. 3B), and serum glycerol (FIG. 3C) levels in controls and TAK-treated mice (4 weeks post treatment) on RD/HFD (10 weeks). Administration of TAK-448 lowers ALT, cholesterol and glycerol levels in HFD-fed mice compared to controls on HFD.

[0016] FIG. 4A and FIG. 4B shows CLAMS analysis displaying heat expenditure (FIG. 4A) and respiratory exchange ratio (RER) (FIG. 4B) in vehicle (VEH, PBS) controls and TAK- 448 treated mice (4 weeks post treatment, 10 weeks on RD/HFD; 5 mice/group).

[0017] FIG. 5A and FIG. 5B. FIG. 5A shows the relative mRNA expression of indicated genes by RT-qPCR in HFD liver samples, normalized to Rpll3a mRNA expression. TAK- 448 treatment reduces the levels of key genes regulating fat production in the liver (triglyceride synthesis and lipogenesis). FIG. 5B is a representative western blot showing expression of indicated protein in HFD livers mice. TAK-448 treatment decreases the protein levels of key regulators of fat production in the liver.

[0018] FIG. 6A through FIG. 6C show densitometric analysis of the western blots shown in FIG. 5B.

[0019] FIG. 7 is a western blot showing pAMPK and total AMPK. TAK-448 treatment activates AMPK, a critical energy sensor, which then inhibits fat formation.

[0020] FIG. 8A and FIG. 8B show densitometric analysis of the western blots shown in FIG. 7 and FIG. 5B, respectively.

[0021] FIG. 9A and FIG. 9B show the relative mRNA expression of inflammatory markers (FIG. 9A) and fibrosis and oxidative stress markers (FIG. 9B) by RT-qPCR in HFD liver samples from mice treated with VEH (controls) or TAK, normalized to Rpll3a mRNA expression. TAK-448 treatment reduces the levels of key genes regulating inflammation and fibrosis in the liver. Mean ± SEM shown. Student’s unpaired t-test, *p < 0.05 compared to VEH controls.

[0022] FIG. 10 is a graph relating to the inhibitory effects of TAK-448 treatment on expression of key regulators of hepatic triglyceride synthesis and de novo lipogenesis. [0023] FIG. 11 is a graph relating to the inhibitory effects of TAK-448 treatment on expression of key regulators of hepatic inflammation.

[0024] FIG. 12 is a graph relating to the effects of TAK-448 treatment on expression of key regulators of hepatic fibrosis.

[0025] FIG. 13 is graph relating to the effects of TAK-448 treatment on expression of hepatic genes regulating mitochondrial and peroxismal beta-oxidation of fat.

[0026] FIG. 14A through FIG. 14D. FIG. 14A is a graph showing body weight (BW) of control (CTRL) and liver KISS1R knock-out (LKO) mice over time on HFD. FIG. 14B is a bar graph showing endpoint body weight for control and LKO mice. FIG. 14C is a photograph of mice on HFD (CTRL and LKO). FIG. 14D is a bar graph showing daily food intake of control and LKO mice averaged over 4 day.

[0027] FIG. 15A and FIG. 15B are sets of micrographs of hematoxylin and eosin stained mouse liver showing steatosis for CTRL and LKO (HDF and RD) mice with high fat (FIG.

3 A) and regular (FIG. 15) diets. Boxed area in FIG. 15B is magnified below.

[0028] FIG. 16 is a bar graph showing liver triglycerides in CTRL and LKO (RD and HFD) mice. LKO mice on HFD have elevated liver triglycerides compared to controls also on HFD. [0029] FIG. 17 shows the relative mRNA expression of Kissl and Kissh by RT-qPCR normalized to Rpll3a mRNA expression in C57BL6 male mice on regular diet (RD) or high fat diet (HFD) for 8 weeks. HFD induces KISS1 and KISS1R expression in the liver.

[0030] FIG. 18A through FIG. 18D. FIG. 18A shows the relative mRNA expression of indicated genes by RT-qPCR in HFD livers from CTRL and LKO mice, showing the knockdown of KISS1R. LKO mice livers are depleted of KISS1R expression compared to controls. Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05 compared to controls.

FIG. 18B shows the body weight of CTRL and LKO mice on regular diet (RD). There is no change in body weight in mice maintained on RD. FIG. 18C and FIG. 18D show CLAMS analysis displaying respiratory exchange ratio (RER) (FIG. 18C) and ambulatory activity (FIG. 18D) of CTRL and LKO mice. * p < 0.05; One-way ANOVA followed by Dunnett’s post-hoc test.

[0031] FIG. 19A and FIG. 19B. FIG. 19A shows the heat expenditure assessed by CLAMS, reflecting lower metabolism in HFD LKO mice. FIG. 19B shows serum levels of the liver enzyme alanine aminotransferase (ALT), a marker for liver disease, is increased in LKO mice on HFD, compared to CTRL on HFD. [0032] FIG. 20A through FIG. 20D show the weight of gastrocnemius muscle (FIG. 20A), tibialis anterior muscle (FIG. 20B), epididymal white adipose tissue (eWAT) (FIG. 20C), and inguinal white adipose tissue (iWAT) (FIG. 20D) in CTRL and LKO mice. Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05 compared to controls. LKO mice on HFD have lower muscle mass and more adipose tissue compared to controls on HFD.

[0033] FIG. 21A and FIG. 21B. FIG. 21A shows the relative mRNA expression of indicated genes in liver samples (HFD) normalized to Rpll3a mRNA expression. Key genes regulating fat formation are elevated in livers from LKO mice on HFD. FIG. 21B provides representative western blots showing the expression of the indicated proteins in liver samples. Proteins regulating fat formation are elevated in livers from LKO (HFD) mice. Mean ± SEM shown; Student’s unpaired t-test, *p < 0.05 compared to control group.

[0034] FIG. 22A through FIG. 22D show densitometric analysis of the expression of the indicated proteins from the western blots in FIG. 21B: FIG. 22A (FASN); FIG. 22B (PPARy); FIG. 22C (CD36); FIG. 22D (pAMPK/total AMPK).

[0035] FIG. 23 A and FIG. 23B. FIG. 23 A is a schematic drawing showing the hepatic triglyceride (TG) synthesis pathway; molecules in bold are upregulated in HFD LKO compared to control (CTRL) livers. FIG. 23B shows the relative mRNA expression of indicated genes by RT-qPCR in LKO liver samples normalized to Rpll3a mRNA expression. Genes regulating triglyceride synthesis are elevated in LKO (HFD) livers.

[0036] FIG. 24 shows densitometric analysis of GYK expression from the western blots in FIG. 21B.

[0037] FIG. 25 A and FIG. 25B. FIG. 25 A is a volcano plot comparing liver lipids measured by mass spectrometry (LC-MS) in CTRL and LKO mice on HFD. Lipid species that are highly elevated in the LKO (HFD) livers are shown on the top right quadrant of the graph. FIG. 25B shows the relative mRNA expression of the indicated genes by RT-qPCR in livers of CTRL and LKO mice maintained on RD, normalized to Rpll3a mRNA expression. Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05 compared to controls.

[0038] FIG. 26A through FIG. 261. FIG. 26A and FIG. 26B show the fasting blood glucose levels (FIG. 26A) and blood glucose levels during a glucose tolerant test (GTT) in CTRL and LKO mice on HFD after a 12-hour fast (FIG. 26B). LKO mice on HFD have worsened type 2 diabetes compared to controls also on HFD. FIG. 26C shows the area under the curve (AUC) of GTT. FIG. 26D shows the blood glucose levels in CTRL and LKO mice on HFD after 6 hour fast during an insulin tolerance test (ITT). FIG. 26E shows the AUC of ITT. Relative mRNA expression of indicated genes by RT-qPCR in CTRL and LKO (HFD) liver samples showing genes regulating glucose metabolism (FIG. 26F), markers for inflammation (FIG. 26G) and fibrosis (FIG. 26H), and mitochondrial oxidative stress (FIG. 261) normalized to Rpll3a mRNA expression. Livers from LKO mice on HFD display elevated levels of genes regulating inflammation and fibrosis. Mean ± SEM shown, Student’s unpaired t-test,

*p < 0.05 compared to controls.

[0039] FIG. 27 is a graph showing the relative mRNA expression of KISS1R.

[0040] FIG. 28A and FIG. 28B are western blots showing the regulation of hepatic PPAR-g by KISS1R signaling. LKO mice livers have increased expression of PPAR-g but decreased expression of phosphorylated PPAR- g (FIG. 28A). This phosphorylation site inhibits PPAR- g activity. In contrast, TAK-448 treatment decreased expression of PPAR-g but increased phosphorylated PPAR- g, indicating PPAR- g activity is decreased (FIG. 28B).

[0041] FIG. 29A is confocal image of endogenous kisspeptin immunostaining (See arrows) in isolated primary hepatocytes.

[0042] FIG. 29B is a graph showing the inhibitory effects of TAK-448 (3 nM), or kisspeptin- 10 (100 nM), on FFA (150 mM oleic acid and 150 mM palmitic acid) loaded triglyceride accumulation in primary mouse hepatocytes.

[0043] FIG. 29C is a graph showing the lack of effects of TAK-448 or kisspeptin- 10 on FFA (150 mM oleic acid and 150 mM palmitic acid) loaded triglyceride accumulation in hepatocytes isolated from LKO mice (lacking KISS1R). * p < 0.05; One-way ANOVA followed by Dunnett’ s post-hoc test.

[0044] FIG. 30 is a graph showing the inhibitory effect of TAK-448 treatment on expression of genes regulating de novo lipogenesis and triglyceride synthesis.

[0045] FIG. 31 A through FIG. 31C. FIG. 31A shows the relative mRNA expression of indicated genes by RT-qPCR in primary mouse hepatocytes isolated from C57BL6 male mice upon kisspeptin (KP) or TAK treatment for 8h, under basal conditions. (n=5) * p < 0.05; One-way ANOVA followed by Dunnett’ s post-hoc test. FIG. 3 IB shows representative western blots showing the effect of kisspeptin treatment on phosphorylation of AMPK (resulting in its activation) to thereby inhibit its downstream substrate ACC, in primary mouse hepatocytes (n=4). FIG. 31C shows KisslR expression in primary mouse hepatocytes from CTRL and LKO mice by RT-qPCR in normalized to Rpll3a mRNA expression (n=4). KISS1R expression is depleted in isolated hepatocytes from LKO mice livers. [0046] FIG. 32A and FIG. 32B provide densitometric analysis of the western blots of FIG. 31B.

[0047] FIG. 33A and FIG. 33B. FIG. 33A provides representative western blots showing expression of the indicated proteins in isolated primary hepatocytes from control and LKO mice. FIG. 33B shows relative mRNA expression of the indicated genes by RT-qPCR in primary mouse hepatocytes isolated from CTRL and LKO mice (n=4), showing the increase in genes regulating fat synthesis upon deletion of KISS1R. Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05.

[0048] FIG. 34A through FIG. 34D provide densitometric analysis of the western blots of FIG. 33A for CD36 (FIG. 34A), FAS (FIG. 34B), PPARy (FIG. 34C), and MOGAT1 (FIG. 34D). Mean ± SEM shown, Student’s unpaired t-test, *p < 0.05 compared to controls.

[0049] FIG. 35A through FIG. 35B is a set of graphs showing TAK-448 treatment in free fatty acid (FFA: palmitate, 100 mM)- loaded mouse primary hepatocytes increases oxygen consumption rate leading to enhanced fatty acid oxidation (FIG. 35A). TAK-448 treatment also increased basal respiration (FIG. 35B), and ATP production (FIG. 35C).

[0050] FIG. 36A through FIG. 36C are graphs showing TAK-448 treatment in FFA (palmitate, 100 mM)-^0e0 human hepatocytes increases oxygen consumption rate over time following treatment. TAK-448 treatment also increased basal respiration (shown in FIG.

36B) and ATP production shown in (FIG. 36C).

[0051] FIG. 37A and FIG. 37B are sets of bar graphs showing that TAK-448 treatment decreases proliferation of human stellate LX2 cells, as observed by a decrease in cell count (FIG. 37A). TAK-448 treatment decreases fibrosis marker gene expression (FIG. 37B) in LX2 cells.

[0052] FIG. 38 A through FIG. 38D are a set of immunofluorescence images showing staining of human liver biopsy from NAFLD patient as indicated for nuclei (FIG. 38 A), endogenous KISS1R (FIG. 38B), stellate cells (FIG. 38C), and an overlay (FIG. 38D).

[0053] FIG. 39A is a graph showing relative mRNA expression in patient liver biopsies. The gene and protein expression of KISS1 and KISS1R is elevated in patient liver biopsies from NAFLD/NASH patients compared to healthy control livers.

[0054] FIG. 39B is a set of western blots;

[0055] FIG. 39C and FIG. 39D show densitometric analysis of the blots in FIG. 39B.

[0056] FIG. 39E is a set of representative histology images showing higher KISS1R staining in adult liver from NAFLD/NASH patients compared to healthy subject. [0057] FIG. 39F is a bar graph showing plasma kisspeptin levels by radioimmunoassay in human subjects; plasma kisspeptin levels are significantly elevated in the NAFLD/NASH patients compared to healthy subjects, suggesting that the increase in kisspeptin maybe a compensatory, protective mechanism aiming to resolve NAFLD.

[0058] FIG. 40 is a schematic drawing showing a working model of the signaling pathway by which KP/KISS1R activation in the liver protects against the development of fatty liver and its progression to NASH. Enhanced activation of KISS1R by potent analog TAK-448 results in the activation of AMPK, which inhibits lipogenesis and reduces fat accumulation. Instead, TAK-448 promotes the breakdown of fatty acids via beta-oxidation to produce energy, for example in the mitochondria.TAK-448 also inhibits the expression and activity of PPAR-gamma, a key promoter of triglyceride synthesis in the liver under obesity conditions. This results in less accumulation of fat, less injury (inflammation) of the liver cells thus inhibiting the progression to NASH.

DETAILED DESCRIPTION

[0059] 1. Definitions

[0060] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Although various methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. However, the skilled artisan understands that the methods and materials used and described are examples and may not be the only ones suitable for use in the invention. Moreover, as measurements are subject to inherent variability, any temperature, weight, volume, time interval, pH, salinity, molarity or molality, range, concentration and any other measurements, quantities or numerical expressions given herein are intended to be approximate and not exact or critical figures unless expressly stated to the contrary.

[0061] The term “about,” as used herein, means plus or minus 20 percent of the recited value, so that, for example, “about 0.125” means 0.125 ±0.025, and “about 1.0” means 1.0 ±0.2. [0062] The term “TAK-448” as used herein, refers to a stable analog of the fully active 10- amino acid C terminus of kisspeptin-54 (kisspeptin- 10); these are peptide products of kispeptin-145, encoded by the KISS1 gene. Kisspeptin-54 was formerly known as metastin and is a ligand for the G-protein coupled kisspeptinel receptor (KISS1R), previously known as GPR54. [0063] The term “treat,” and its cognates such as “treatment,” as used herein, refers to obtaining a desired pharmacologic and/or physiologic effect. Thus, “treatment” includes (a) preventing the condition or disease or symptom thereof from occurring in a subject which may be predisposed to the condition or disease but has not yet been diagnosed as having it;

(b) inhibiting the condition or disease or symptom thereof, such as, arresting its development; and (c) relieving, alleviating or ameliorating the condition or disease or symptom thereof, such as, for example, causing regression or partial regression of the condition or disease or symptom thereof.

[0064] The term “prevent,” and its cognates such as “prevention,” as used herein, refers to reducing the likelihood of occurrence of a disease or condition, reducing the severity of a disease or condition, and partially or totally stopping the disease or condition in a subject. [0065] The term “subject,” as used herein, refers to a mammal, preferably a human patient, including human children patients.

[0066] The term “in need thereof,” as used herein, refers to a subject suffering from or suspected of suffering from non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis.

[0067] The term “therapeutically effective amount,” as used herein, refers to an amount, dosage, or dosage regimen that produces a therapeutic effect, preferably a desired pharmacologic and/or physiologic result.

[0068] The term “administer,” and its cognates, such as “administration,” refers to contact of a compound with a subject according to methods and routes known in the art of pharmaceutical science.

[0069] The term “fatty liver” refers to the condition where the liver of a subject contains 5% or more fat. Conditions falling within the category of “fatty liver” include, but are not limited to, fatty liver disease, hepatitis, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, alcoholic steatohepatitis, liver fibrosis, cirrhosis of the liver, jaundice and liver cancer, or any condition where the liver contains 5% or more fat.

[0070] The term “NAFLD/NASH,” as used herein, refers to non-alcoholic fatty liver disease and/or non-alcoholic steatohepatitis. NAFLD encompasses a spectrum of pathological conditions, including steatosis (fatty liver), nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis (excessive scarring of liver).

[0071] The term “conservative variant” with respect to a natural or synthetic peptide or peptide analog, refers to a sequence that is about 90% or more identical to the peptide, for example with one amino acid substituted, added, or deleted in the sequence. This term also includes chemical variants of the peptide, such as a chemical modification of the amino acid side chains, including addition of a methyl, ethyl, halo, tri-fluoro, hydroxyl, carboxylate, amino, methylamino, and the like to the structure of the compound.

2. Overview

[0072] The present invention will provide a therapy for metabolic disorders such as NAFLD and NASH through the administration of TAK-448, a long-lasting synthetic analog of kisspeptin-10, a naturally occurring peptide found in the blood. Kisspeptin signals via the kisspeptin receptor (KISS1R), a G protein-coupled receptor and both kisspeptin and KISS1R are expressed by the liver. Kisspeptin-54 peptide has been administered to healthy men which has been shown to enhance insulin secretion, without altering food intake or appetite.

3. Embodiments of the invention

[0073] This report provides the first evidence of a novel function of KISS 1R as a key regulator of hepatic lipogenesis. Although KISS1R is expressed in the liver, its biological function in the liver remained unknown. The goal of the present study was to determine the role of KISS1R in the development and progression of fatty liver, such as NAFLD, and to provide compositions and methods for use in prevention and treatment of NAFLD/NASH and other conditions involving accumulation of fat in the liver. Using a hepatic Kissl r knockout (LKO), we found that hepatic Kisslr deficiency exacerbated hepatic steatosis, inflammation and fibrosis in a mouse model of NAFLD. HFD LKO mice showed aggravated metabolic parameters such as increased body weight, elevated levels of liver triglycerides (TGs), elevated fasting glucose and insulin resistance and an increase in inflammatory and fibrosis markers.

[0074] These phenotypes suggest that hepatic KISS 1/KISS 1R ablation plays a crucial role in negatively regulating the development of the NAFLD phenotype and related metabolic deterioration. Thus, to test the hypothesis that hepatic KISS1R plays a protective role in NAFLD, insulin resistant wild-type mice were treated with TAK-448, a protease-resistant KP analog with potent agonist activity comparable to KP10. We found that in insulin-resistant wild-type mice, TAK treatment suppressed lipid accumulation in livers, reduced serum TGs, cholesterol and free fatty acids (FFAs) and lowered adipose mass. Additionally, TAK treatment prevented a gain in body weight without changing food intake and improved glucose tolerance and insulin sensitivity. Importantly, TAK administration resulted in a reduction in key genes regulating inflammation and fibrosis. Collectively, these findings demonstrate a critical protective role of KISS1R against the development of fatty liver (steatosis) and NASH. Human data showed a significant increase in KISS1 and KISS1R levels in liver biopsies and elevated plasma kisspeptin levels from NAFLD/NASH patients compared to healthy subjects. This might be a protective, compensatory mechanism to lower hepatic fat accumulation. However, the endogenous activation of KISS1R is clearly not sufficient to safeguard against the development of NAFLD. These results illustrate the translational relevance of our pre-clinical findings as they mirror the results observed in a diet induced mouse models of NAFLD. Importantly, TAK-448 treatment also reduced the proliferation of human hepatic stellate cells that play a key role in liver fibrosis, suggesting a protective role of TAK-448 in preventing fibrosis.

[0075] We also delineated the cellular pathways by which KISS1R regulates lipogenesis (see FIG. 40). Our findings reveal that KISS1R activates AMPK in vivo in HFD livers and in vitro, in isolated primary hepatocytes, leading to an inhibition of de novo lipogenesis (DNL) and TG accumulation underlying the protective effects of KISS/KISS 1R on steatosis. DNL (conversion of carbohydrates to fat) is upregulated in NAFLD and activation of AMPK inhibits DNL by phosphorylating ACC and reducing its activity, promoting fatty acid utilization. TAK-448 treatment increased the breakdown of free fatty acids via a process called beta-oxidation. AMPK activation also leads to the downregulation of lipogenic gene expression by directly phosphorylating the master transcriptional regulator of lipogenesis, SREBP-1.

[0076] AMPK activation has been shown to attenuate TG synthesis, resulting in an antisteatotic effect by two possible mechanisms. First, AMPK activation inhibits Liver X receptor a (LXRa) activity in the liver; LXRa is a lipid sensor that promotes fatty acid synthesis and leads to hypertriglyceridemia. Second, AMPK activation inhibits PPARy transcription. The mechanism by which KP activates AMPK is currently not known. Activation of AMPK requires phosphorylation of threonine 172 (T172) via increases in the AMP:ATP ratio and elevation of intracellular Ca2+(38). Several reports suggest that activation of Ca2+/calmodulin-dependent protein kinase b (CaMKK ) plays a physiological role in activating AMPK in mammalian cells. Since KISS1R activation increases intracellular Ca2+(41), it is likely that KISS1R activates AMPK via the CaMKK pathway. [0077] PPARy expression is low in healthy livers but rises significantly in NAFLD and contributes to the development of hepatic steatosis by regulating de novo lipid metabolism. Furthermore, PPARy plays a major role in directly upregulating genes/pathways involved in TG synthesis such as Gykl , the key enzyme in fatty acid esterification, Cd36, the fat importer, and Mogatl, which esterifies monoacylglycerol to form diacylglycerol (DAG), the precursor of TG. Suppression of PPARy-dependent MOGAT1 expression inhibits hepatic steatosis, whereas CD36-dependent FFA uptake and MOGAT mediated fatty acid esterification promote steatosis. PPARy and MOGAT overexpression has also been observed in humans with NAFLD. The finding that TAK inhibited the expression of PPARy, CD36, and MOGAT1 has significant clinically implications, given the established link between DAG negatively regulating hepatic insulin sensitivity. In conclusion, our study suggests that the hepatic KP/KISS1R signaling system inhibits hepatic de novo lipogenesis in hepatocytes via a mechanism involving AMPK-PPARy signaling, further suggesting that activation of KISS1R signaling is a promising therapeutic target for the treatment of NAFLD.

[0078] Specifically, the pre-clinical studies described here use an established mouse model of NAFLD in which male mice are fed a Western high fat diet (HFD, 60% kcal fat), compared to a regular diet (RD, 4% kcal fat). Using this model, we found that the sub cutaneous administration of the kisspeptin analog (TAK-448) protected against the development of fatty liver in the mouse NAFLD model compared to mice treated with Vehicle (phosphate buffered saline, PBS) control (see FIG. 1A through FIG. 1J and FIG.3A and FIG. 3C). Specifically, TAK-448 administered for one month to diabetic mice (FIG. 2A and FIG. 2B) prevented steatosis (the accumulation of liver triglycerides) and prevented a rise in liver and serum triglycerides (FIG. 1C), and lowered blood cholesterol (FIG. 3B), fatty acids (FIG. ID) and glycerol which is triglyceride building block (FIG. 3C). TAK-448 treatment decreased the levels of the liver enzyme, ALT, a clinical biomarker for fatty liver disease. See FIG. 3A. TAK-448 treatment also protected against peripheral fat accumulation and insulin resistance. See FIG. IF through FIG. 1J. There was no change in food intake in TAK-treated mice compared to Controls, both on HFD (FIG.2C).

[0079] In addition, in mice fed HFD bearing a deletion of liver KisslR (LKO), a greater increase in body weight (FIG.14), liver steatosis (FIG 15) and liver triglycerides (FIG. 16) were observed compared to littermate controls on HFD, despite no change in food intake (FIG. 14D). This implicates a protective role of the kisspeptin/KisslR pathway in preventing the pathogenesis of NAFLD. See FIG. 14, FIG. 15 and FIG. 16. KisslR knock-out animals also were glucose intolerant and insulin resistant, compared to controls (all on HFD). See FIG. 26B through FIG. 26E. The livers from hepatic KISS1R knock-out mice displayed a significant increase in proinflammatory cytokines (Interleukins (IL)-la, Mip2, IP10; see FIG. 26G) and biochemical markers for NASH/fibrosis (e.g. TGFbeta, collagen (see FIG. 26H), compared to controls (all on HFD).

[0080] Kisspeptin also has actions on the brain, regulating the central reproductive system. Chronic administration of kisspeptin results in suppression of sex steroid hormone synthesis. This is mimicked by the long-acting TAK-448 which has been used in men with prostate cancer (two Phase 1 clinical trials) to lower testosterone levels. Additionally, TAK-448 under a different name (MVT-602) is being tested by MYOVANT to treat infertility in women and is currently in Phase 1 and Phase 2 clinical trials.

[0081] TAK-448 is an oligopeptide analog of the fully active 10-amino acid C terminus of kisspeptin-54 (kisspeptin- 10). It has a half-life of 4 hours in the blood, in contrast to kisspeptins which are rapidly degraded within minutes. TAK-448 is a potent Kisspeptin 1 receptor (KISS1R, or GPR54) agonist. KISS1R is a G protein-coupled receptor that binds kisspeptins. Kisspeptin is encoded by the metastasis suppressor gene KISS1, which is expressed in a variety of endocrine and gonadal tissues. Kisspeptin and KISS1R play key roles in mammalian reproduction due to their involvement in the onset of puberty and control of the hypothalamic -pituitary-gonadal axis. It has been used in trials studying the treatment of prostate cancer, low testosterone, prostatic neoplasms, and hypogonadotropic hypogonadism. The structure of TAK-448 is:

TAK-448

[0082] See Table 1, below, for sequences of interest. Table 1. Peptide Sequences.

[0083] Subjects that can be treated according to embodiments of the invention include any mammal, including laboratory animals, companion animals, farm animals, zoo animals, and the like, including humans. Preferred subjects are humans and rodents. A suitable subject for the invention preferably is a human that is suspected of having, has been diagnosed as having, or is at risk of developing a disease that can be ameliorated, treated or prevented by administration of TAK-448, including any disease or condition involving fatty liver or accumulation of fat in the liver.

[0084] TAK-448 can be administered to prevent, delay, slow, reverse, or halt disease progression in any disease or condition involving accumulation of fat in the liver or fatty liver. Such conditions include, but are not limited to, (1) NAFLD, (2) NASH, (3) fatty liver disease, (4) hepatitis, (5) liver fibrosis, (6) cirrhosis of the liver, (7) jaundice, (8) liver cancer, or (9) any condition where the liver of a subject contains 5% or more fat.

[0085] The term “NAFLD/NASH,” as used herein, refers to non-alcoholic fatty liver disease and/or non-alcoholic steatohepatitis. NAFLD encompasses a spectrum of pathological conditions, including steatosis (fatty liver), nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis (excessive scarring of liver).

[0086] The compounds contemplated for use in the invention described herein include, but are not limited to, TAK-448 or any conservative variant thereof, and kisspeptin-10 or any conservative variant thereof. A conservative variant is a peptide of about 90% or more identity of sequence, or a chemically modified peptide as described above. For example, a conservative variant of kisspeptin-10 includes deletions, substitutions, and additions of kisspeptin-10, as well as chemical variants, such as, for example, those exemplified in Tables 2 through Table 6, below. A conservative variant of TAK-448 includes deletions, substitutions, and additions, of TAK-448, as well as chemical variants, such as, for example, those exemplified in Table 2 through Table 6, below.

Table 2. Exemplary Compound Variants.

Table 3. Sequences and Binding Affinities of Kisspeptin-10 Analogs

*Tnformation from Curtis et al., 2009; **Tnfoimation from Decourt et al., 2016; ****ICso

(means +/- SE; n = 3-5) against [ ¹²⁵ I]KP-54 binding to KISS1R in CHO-KISS1R membrane preparations. Each receptor binding assay was carried out in triplicate.

Table 4. Kisspeptin Analogs, Asami et al. (Biological activities of metastin analogs substituted between positions 50 and 51. a Agonist activities of all peptides were evaluated in a bifunctional assay of human

OT7T175, an intracellular calcium mobilization assay using fluorometric imaging plate reader technology. EC50 values of all peptide analogs were calculated using sigmoidal dose response curves. b EC50 values of mestatin (45-54) were calculated as the average value of 13 independent experiments. c Receptor binding affinities of the synthesized peptides were determined as K50 values d IC50 value of mestatin (45-54) was calculated as the average value of three independent experiments. e Residual ratio after incubation in mouse serum one hour at 37°C. f Not determined.

Table 5. Kisspeptin Analogs Substituted at Position 47, Asami et al. (Biological activities of decapeptide mestatin analogs substituted at position 47). a Agonist activities of all peptides were evaluated in a bifunctional assay of human OT7T175, an intracellular calcium mobilization assay using fluorometric imaging plate reader technology. ECso values of all peptide analogs were calculated using sigmoidal dose response curves. b EC50 values of mestatin (45-54) were calculated as the average value of 13 independent experiments. c Receptor binding affinities of the synthesized peptides were determined as K50 values d IC50 value of mestatin (45-54) was calculated as the average value of three independent experiments. e Residual ratio after incubation in mouse serum one hour at 37°C. f Not determined.

Table 6. Kisspeptin Analogs, Nishizawa et al. (2019) Structures, biological activities, and HPLC retention times of Kp analogs.

R-AA ⁴ 5-AA ⁴ 6-AA ⁴⁷ -AA ⁴ 8-AA ⁴ 9-Phe-AA51-Leu-AA53-AA54-NH2

Compound AA ⁴⁵ A A ⁴⁶ AA ⁴⁷ AA ⁴⁸ AA ⁴⁹ AA ⁵¹ AA ⁵³ AA ⁵⁴

R

Metastin Tyr Asn Trp Asn Ser Gly Arg Phe

(45-54)

H D-Tyr D-Pya(4) Asn Ser azaGly Arg(Me) Phe

H D-Tyr Trp Asn Ser azaGly Arg(Me) Phe

H - Trp Asn Ser azaGly Arg(Me) Phe

Ac - Trp Asn Ser azaGly Arg(Me) Phe

3-(indol-3-yl) - - Asn Ser azaGly Arg(Me) Phe propionyl

3 -pheny lpropiony 1 Asn Ser azaGly Arg(Me) Phe

3-(4-pyridyl) Asn Ser azaGly Arg(Me) Phe propionyl

3-(indol-3-yl) - Ser azaGly Arg(Me) Phe propionyl

3-(indol-3-yl) - - azaGly Arg(Me) Phe propionyl 0 H - - azaGly Arg(Me) Phe1 Ac - - azaGly Arg(Me) Phe n-hexanoyl azaGly Arg(Me) Phe benzoyl azaGly Arg(Me) Phe benzyl azaGly Arg(Me) Phe

3-(indol-3-yl) azaGly Arg(Me) Trp propionyl benzoyl azaGly Arg(Me) Trp

2-pyridylcarbonyl azaGly Arg(Me) Trp 3 -pyridy lcarbony 1 azaGly Arg(Me) Trp 4-pyridylcarbonyl azaGly Arg(Me) Trp 3 -furany lcarbony 1 azaGly Arg(Me) Trp 2-pyrolylcarbonyl azaGly Arg(Me) Trp

4-imidazolyl azaGly Arg(Me) Trp carbonyl phenylacetyl azaGly Trp

A t o L/ϊί= cyclohexanoyl azaGly Arg(Me) Trp propionyl azaGly Arg(Me) Trp isobutyryl azaGly Arg(Me) Trp cyclopropyl azaGly Arg(Me) Trp carbonyl a EC50 values [nM (95% confidence interval)] of [Ca2+] increasing activities of all peptide analogs were evaluated in CHO cells expressing human KISS1R. b Retention times (tret) of peptide analogs were measured via RP-HPLC. Elution conditions: linear density gradient elution on Merck Chromolith® Performance RP- 100 mm), with eluents A/B = 95/5-35/65 (10 min), using 0.1% TFA in water as eluent A and 0.1% TFA- containing acetonitrile as eluent B; flow rate: 3.0 mL/min.

[0087] The compounds of the invention also include the base, and any pharmaceutically acceptable hydrate, solvate, acid or salt, and can be amorphous or in any crystalline form, or as an oil or wax. Any pharmaceutically acceptable salt can be used, as may be convenient. [0088] Generally, these salts are derived from pharmaceutically and biologically acceptable inorganic or organic acids and bases or metals. Examples of such salts include, but are not limited to: acetate, adipate, alginate, ammonium, aspartate, benzoate, benzenesulfonate (besylate), bicarbonate, bisulfate, butyrate, citrate, camphorate, camphorsulfonate, carbonate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptanoate, glycerophosphate, glycolate, hemisulfate, heptanoate, hexanoate, hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate, lactate, magnesium, maleate, malonate, methanesulfonate (mesylate), 2-naphthalenesulfonate, nicotinate, nitrate, oxalate, palmoate, pectinate, persulfate, 3-phenylpropionate, phosphate, picrate, pivalate, potassium, propionate, salicylate, sodium, succinate, sulfate, tartrate, thiocyanate, toluenesulfonate (tosylate) and undecanoate salts.

[0089] The compounds also include any or all stereochemical forms of the therapeutic agents (i.e., the R and/or S configurations for each asymmetric center). Therefore, single enantiomers, racemic mixtures, and diastereomers of the therapeutic agents are within the scope of the invention. Also within the scope of the invention are steric isomers and positional isomers of the therapeutic agents. The therapeutic agents of some embodiments are also meant to include compounds which differ only in the presence of one or more isotopically enriched atoms. For example, therapeutic agents in which one or more atom is replaced by, for example, deuterium, tritium, ¹³ C, ¹⁴ C (or any isotopic labels as commonly used in the art such as phosphorus, calcium, iodine, chlorine, bromine, or any other convenient element for isotopic labeling) are within the scope of this invention.

[0090] Compounds such as TAK-448, and the other compounds according to embodiments of the invention, can be administered to the subject by any suitable route or method as known in the art. Suitable routes of admiration include, but are not limited to, oral administration, intravenous, intraarterial, intrathecal, intraperitoneal, intradermal, subcutaneous, intramuscular or intraperitoneal injections, rectal or vaginal administration by way of suppositories or enema, transmucosal, transdermal, buccal, nasal, inhalation, sublingual, topical, or local administration directly into or onto a target tissue, or administration by any route or method that delivers a therapeutically effective amount of the drug or composition to the cells or tissue to which it is targeted. When administration is oral, the dosage form preferable is a delayed release or other formulation that allows the compound to be absorbed prior to degradation of a peptide or peptide analog compound. Preferably, the methods of embodiments of this invention involve administration subcutaneously or intravenously. The administration can be given by transfusion or infusion, and can be administered by an implant, an implanted pump, or an external pump, or any device known in the art.

[0091] In preferred method embodiments, the compounds described herein are formulated and are administered as a pharmaceutical composition that includes a pharmaceutically acceptable carrier and one or more pharmaceutical agent, including one or more of the inventive compounds described herein, and including one or more of the inventive compounds described herein optionally with an additional agent, such as a fatty liver reducing drug of the same or another class, for a combination therapy.

[0092] Exemplary compounds for use in a combination treatment, simultaneously or sequentially with the compounds of this invention, such as TAK-488, include but are not limited to an ACC inhibitor, AMPK, AKR-001, aramchol, ASC40, AZD7687, BI-1467335, BI089-100, BMS-986036, canagliflozin, cenicriviroc, cilofexor, dapagliflozin, DGATEDP- 305, elafibranor, elobixibat, empagliflozin, emricasan, exenatide, EYPOOla, FALCON1 (PEG-FGF21, an FASN inhibitor, fenofibrate, firsocostat, an FXR agonist, GR-MD-02, IONIS-DGAT2 _Rx , ipragliflozin, licogliflozin, liraglutide, luseogliflozin, FY3202328,

MET409, MGE-3196, MK-4074, MSDC-0602K, MT-3995, NGM282, nidufexor, OAT-1251, obeticholic acid, OCA, OWE833, PF-05221304, PF-06835919, PF-06865571, PF-06882961, pioglitazone, PX-102, PXE770, PXS-5153A, seladelpar, selonsertib, semaglutide, simtuzumab, TERN-101, TERN-201, troifexor, TTP273, vitamin D, vitamin E, VK2809, and volixibat. In addition, treatment by administration with the compounds TAK-448, kisspeptin, and their variants, can be accompanied by a first line treatment including diet and exercise changes and weight loss.

[0093] A pharmaceutically acceptable carrier refers to any convenient compound or group of compounds that is not toxic and that does not destroy or significantly diminish the pharmacological activity of the therapeutic agent with which it is formulated. Such pharmaceutically acceptable carriers or vehicles encompass any of the standard pharmaceutically accepted solid, liquid, or gaseous carriers known in the art, such as those discussed in the art. A suitable carrier depends on the route of administration contemplated for the pharmaceutical composition.

[0094] A non-inclusive list of carriers and vehicles contemplated for use with the invention follows: fillers, diluents, adjuvants, pH adjusters, buffers, preservatives, binders and disintegrants, solvents, lipids, liposomes, emulsions, suspensions, and containers (e.g., ampoules, bottles, pre-filled syringes, and the like).

[0095] Liquid carriers can be in the form of a solution, suspension, emulsion, oil, gel, and the like, and include, for example aqueous solution (e.g., saline solutions, phosphate-buffered saline solutions, Ringer’s, and the like), oil-in- water or water-in-oil emulsions, liposomes, and the like. Gaseous carriers can include, for example air, oxygen, fluorocarbons, dispersing agents, and the like. Solid carriers can include, for example, starch (e.g., corn starch, potato starch, rice starch, and the like), cellulose (e.g., microcrystalline cellulose, and the like), sugars (e.g., lactose, sucrose, glucose, and the like), clays, minerals (e.g., talc, and the like), gums, flavorings, preservatives, colorings, taste-masking agents, sweeteners, lipids, oils, solvents, saline solutions, emulsifiers, suspending agents, wetting agents, dispersants, binders, lubricants (e.g., magnesium stearate and the like), salts, pH modifiers (e.g., acids or bases), buffers, and the like.

[0096] Pharmaceutical compositions suitable for injection comprise sterile aqueous solutions (where water soluble) or dispersions, suspensions or emulsions, and sterile powders or granules for the extemporaneous preparation of sterile injectable solutions or dispersions. For intravenous administration, suitable carriers comprise physiological saline, bacteriostatic water, Cremophor EL™ (BASF™, Parsippany, N.J.) or (e.g., phosphate) buffered saline (PBS). In all cases, the composition must be sterile and should be fluid to the extent that easy syringability exists. It should be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the selected particle size in the case of dispersion and by the use of surfactants. Prevention of the action of microorganisms can be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, and the like. In some cases, isotonic agents are included in the composition, for example, sugars, polyalcohols such as mannitol, sorbitol, or sodium chloride. Prolonged absorption of an injectable composition can be achieved by including in the composition an agent that delays absorption, for example, aluminum monostearate or gelatin.

[0097] Extended and sustained release compositions also are contemplated for use with and in the inventive embodiments. Thus, suitable carriers can include any of the known ingredients to achieve a delayed release, extended release or sustained release of the active components.

[0098] Routes of administration are determined by the person of skill according to convenience, the health and condition of the subject to be treated, and the location and stage of the condition to be treated. Therefore, the forms which the pharmaceutical composition can take will include, but are not limited to: tablets, capsules, caplets, lozenges, dragees, pills, granules, oral solutions, powders for dilution, powders for inhalation, vapors, gases, sterile solutions or other liquids for injection or infusion, transdermal patches, buccal patches, inserts and implants, rectal suppositories, vaginal suppositories, creams, lotions, oils, ointments, topical coverings (e.g., wound coverings and bandages), suspensions, emulsions, lipid vesicles, and the like.

[0099] Treatment regimens include a single administration or a course of administrations lasting two or more days, including a week, two weeks, several weeks, a month, two months, several months, a year, or more, including administration for the remainder of the subject’s life. The regimen can include multiple doses per day, one dose per day or per week, for example, or a long infusion administration lasting for an hour, multiple hours, a full day, or longer.

[0100] Suitable dosages can be determined by the treating physician depending on the patient, the condition to be treated, and the severity of the condition to be treated. Such dosages can include any amount, dosage, or dosage regimen that produces a desired result. Dosage amounts per administration include any amount determined by the practitioner, and will depend on the size of the subject to be treated, the state of the health of the subject, the route of administration, the condition to be treated or prevented, and the like.

[0101] In general, it is contemplated that for the majority of subjects, a dose in the range of about 0.01 nmol per hour to about 10 nmol per hour is suitable, preferably about 0.1 nmol per hour to about 5 nmol per hour, are useful, given over a course of about 1 hour to about 72 hours, or about 24 hours to about 48 hours, or over a period of days, weeks, or longer. This dose can be administered weekly, daily, or multiple times per day, or as a continuous infusion, transdermal formulation, or depot formulation.

[0102] In addition, a single injected dose of about 0.01 mg, about 0.02 mg, about 0.025 mg, about 0.05 mg, about 0.1 mg, about 0.2 mg, about 0.5 mg, about 1 mg, about 2 mg, about 3 mg, about 4 mg, about 5 mg, or more can be administered. Alternatively, a single injected dose of about 0.002 pmol/kg, about 0.004 pmol/kg, about 0.008 pmol/kg, about 0.01 pmol/kg, about 0.025 pmol/kg, about 0.5 pmol/kg, about 0.75 pmol/kg, about 1 pmol/kg, about 2 pmol/kg, about 5 pmol/kg, about 8 pmol/kg, about 10 pmol/kg, or more can be administered.

4. Summary of Results

[0103] Hepatic kisspeptin receptor (KISS1R) knock-out mice fed with HFD (Western high fat diet, 60% kcal fat) have a greater increase in body weight, liver steatosis, elevated liver triglycerides and higher levels of blood triglyceride and ALT (clinical marker for fatty liver), when compared to littermate controls on HFD, despite no change in food intake. This implicates the pathologic role of kisspeptin/KisslR pathway in the pathogenesis of NAFLD and other fatty liver conditions.

[0104] Hepatic KisslR knock-out mice were also glucose intolerant and insulin resistant, compared to controls (all on HFD). The livers from hepatic KISS1R knock-out mice livers displayed a significant increase in biochemical markers for NASH/fibrosis (e.g. TGF , collagen), and proinflammatory cytokines (Interleukins (IL)-la, Mip2, IP10), compared to controls (all on HFD).

[0105] Subcutaneous administration of TAK-448 protected HFD-fed mice against the development of NAFLD (fatty liver or steatosis) and its progression to NASH, compared to mice treated with Vehicle (PBS) control.

[0106] TAK-448 administered for one month to HFD-fed mice prevented the accumulation of liver triglycerides and the rise in triglycerides, free fatty acids and glycerol (triglyceride building blocks) in the blood. These changes occurred without a change in food intake, compared to vehicle-treated controls on HFD who developed NAFLD.

[0107] TAK-448 treatment also protected against peripheral fat accumulation and insulin resistance, and protected against the development of NASH by reducing the expression of key genes regulating inflammation and fibrosis (hallmarks of NASH).

5. Examples

[0108] This invention is not limited to the particular processes, compositions, or methodologies described, as these may vary. The terminology used in the description is for the purpose of describing the particular versions or embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, the preferred methods, devices, and materials are now described. All publications mentioned herein, are incorporated by reference in their entirety; nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention. Example 1: Methods and Materials.

A. Animals. [0109] Animal studies were approved according to guidelines established by the Institutional Animal Care and Use Committee at Rutgers University. Kiss lr Alb-Cre knockout mice were generated by crossing a male Alb-Cre+/- to a female Kissl Alb-Cre mice were purchased from Jackson Laboratories™. The L7.n.n//tI ^' /P mouse was generated according to know methods. The FI generation was Kisslril/+, AlbCre+/- or Kisslrfl/+, AlbCre-/-. The Kisslrfl/+, AlbCre+/- was back-crossed to the L7.n.n/HΊ/P to generate Kissl ήM\l, AlbCre+/- (liver knockout: LKO) and Kissl rf 1/fl (littermate controls). Mice were housed in a pathogen- free barrier facility maintained on a 12-hour light/dark cycle.

[0110] Four-week-old male LKO and control mice were fed a high fat diet (HFD: 60% kcal fat, 0.2796% cholesterol, 20% calories from carbohydrate (Research Diets™ catalog #D12492, New Brunswick, NJ) or regular control chow diet (RD). Mice were group-housed and provided food and water ad libitum. Five months after commencing the designated diet, a glucose tolerance test was performed, followed by insulin tolerance test a week later. Total body weights were measured weekly for 20 weeks after commencing the designated diet and then animals were euthanized.

B. Administration of KP- analog TAK-448.

[0111] C57BL6/J male mice (4 weeks of age) were maintained on a HFD or RD for 6 weeks and then fasting blood glucose was measured. An Azlet™ mini-osmotic pump model 2004 containing TAK-448 (0.3 nmol/hour) or PBS (vehicle controls) were inserted subcutaneously into the flanks of mice, according to known methods. Animals were treated for 4 weeks unless otherwise indicated and maintained on RD or HFD (total of 10 weeks).

C. Metabolic Tests.

[0112] Blood glucose measurements were obtained via a small nick in the lateral tail vein using a glucometer (Bayer Contour™). For glucose tolerance tests, mice were fasted for 12 hours and then injected intraperitoneahy with D-glucose (lg/kg). For the insulin tolerance tests, mice were fasted for 6 hours and then injected intraperitoneahy with insulin (0.5 U/kg; Novo Nordisk™).

D. Metabolic Cage Assessments.

[0113] Mice where individually housed in an 8-chamber Clinical Laboratory Animal Monitoring System (CLAMS) with controlled light and feeding. Carbon dioxide output, oxygen update, respiratory exchange ratio (RER), ambulatory movement, and feeding were measured over a 4-day period.

E. Insulin, Glycerol, Triglycerides, ALT, FFA, and Cholesterol Measurements. [0114] Serum insulin levels were measured using the Ultra-Sensitive Mouse Insulin ELISA Kit (Crystal Chem™). Seram glycerol levels were measured using the Glycerol Assay Kit (Sigma™). Liver triglycerides were measured using the triglyceride quantification kit (MBL™ international Catalog # JM-K622-500). Lree fatty acids were measured using the Lree Latty Acid Quantification Kit (Sigma™, MAK044-1KT). ALT levels were measured using Liquid ALT (SGPT) Reagent set according to the manufacturer’s instructions; cholesterol levels were measured using the Cholesterol set according to the manufacturer’s instructions.

L. Tmmunoblot Assays.

[0115] Tmmunoblot assays were conducted according to known methods. Mouse liver tissue or primary hepatocytes were homogenized in RIPA lysis buffer containing protease inhibitors and centrifuged at 4°C; the protein expression in lysates was analyzed by Western blot analysis. Protein was separated using SDS-PAGE and probed using the following antibodies: Abeam™ (rabbit anti-KISSIR 1:1000; rabbit anti-MOGATl 1:1000), Cell Signaling Technology™ (rabbit anti-pAMPK, rabbit anti-AMPK, rabbit anti-pACC, rabbit anti-LASN, rabbit anti-PPAR-g, rabbit anti-CD36, and rabbit anti-GYK all 1:1000), Proteintech™ (rabbit anti-KISSl 1:750). Mouse anti-b actin (1:5000, Thermo Pisher Scientific™) or anti-vinculin (1:1000, Bio-Rad™) were used for loading control. Protein was then incubated for 1 hour in horseradish peroxidase (HRP) -conjugated rabbit (1:2500, Cell Signaling Technology™) or mouse (1:2500, Cell Signaling Technology™) secondary antibody. Blots were imaged by chemiluminescence with ChemiDoc™ Touch imaging system (Bio-Rad™), SuperSignal and West Dura Extended Duration Substrate (Thermo Scientific™). Protein levels were quantified using Image Lab Software (Bio-Rad™).

G. Quantitative Real-Time PCR (qPCR).

[0116] Total RNA was extracted from cells using the Trizol method. Reverse transcription was done according to manufacturer’s instructions using iScript RT Supermix (Bio-Rad™). Gene expression was determined using SYBR green real-time qPCR (RT-qPCR) as described previously using primers shown in Table 7, below. The following primers were purchased from BioRad™ (validated PCRPrime™ primers): Srebpl, Aqp3, Aqp9, Gpat2, Agpat2,

Dgatl, Dgat2, Mogatl, Slc2a2, Dgkg, Dgkh, Lgpatl, Sodl, Sod2, Gss, Ucp2, and Gpam. II- 13 was purchased from Qiagen™ (QT00099554). Primers for Srebfl, Aqp3, Aqp9, Gpat2, Agpat2, Dgatl, Dgat2, Mogatl, Slc2a2, Lgpatl, Sodl, Sod2, Gss, Ucp2, and Gpam are pre made and were purchased from BioRad™. Table 7. Primer Sequences. H. Histological Analysis.

[0117] Liver tissue was immediately fixed in 10% neutral formalin after mice were euthanized. Tissue was processed for histology by the Research Pathology Services at Rutgers University. Livers were sectioned into 5 pm thick sections and stained with hematoxylin and eosin. Sections were examined by light microscopy for histopathological changes.

I. Metabolomic analysis by liquid chromatography-mass spectrometry (LC-MS).

[0118] Metabolomics analysis of serum and liver by LC-MS was conducted according to known methods. LC-MS analysis of cell metabolites was conducted on Q Exactive Plus Hybrid Quadrupole Orbitrap mass spectrometer (Thermo Fisher Scientific™) and with hydrophilic interaction chromatography. Data was obtained using the MAVEN software with each labeled isotope (mass accuracy window: 5 ppm). Labeled isotope natural abundance and impurity were corrected using the AccuCor package coded in R.

J. Mouse Primary Hepatocyte Studies.

[0119] Primary hepatocytes from mice were isolated according to known methods. Mice (wild-type, C57BL6) or LKO and littermate controls were anesthetized using a ketamine/xylazine mixture (Henry Schein™). The liver was cannulated via the hepatic portal vein and first perfused with 37°C Kreb’s Ringer solution containing EGTA for 10 minutes. After the first wash, a second Kreb’s Ringer solution containing CaC12 and LIB ERASE (Roche™) was used until the liver was thoroughly perfused. Hepatocytes were filtered through a gauze mesh and resuspended in William’s Media E (Sigma™) with 10 % FBS (Sigma™), 200 nM dexamethasone (Sigma™), 5mM pen/strep (Fisher™), 2 mM L- glutamine (Fisher™). Cells were plated at a density of 3 x 10 ⁵ on 6-well collagen-coated plates (Sigma™). Hepatocytes were left to recover overnight and then were serum starved for 3 hours prior to experiments. For free fatty acid (FFA) loading, 150 mM oleic and 150 mM palmitic acid was conjugated with 2% BSA (0.3 mM). Cells were loaded with FFA post isolation and left to recover overnight prior to serum starvation, and then treated with KP-10 or TAK.

K. Human hepatocyte HepaRG cells

[0120] Human hepatic HepaRG cells were purchased from Thermo Fisher Scientific™.

Cells were grown to confluence in Williams E Media supplemented with 10% fetal bovine serum, Penicillin-Streptomycin (10,000 U/mL), 2 mM L-glutamine, 5 microgram/mL Insulin (Humulin R.), 50 and micromolar hydrocortisone hemisuccinate. Confluent cells were differentiated by supplementing the growth media with 2% DMSO for two weeks, to obtain confluent differentiated cultures containing both hepatocyte-like and hepatic progenitors after which the cells were passaged and used for experiments.

L. Triglyceride Synthesis

[0121] Free fatty acids (150 mM oleic and 150 mM palmitic acid) was conjugated with 2% BSA (0.3 mM). Cells were loaded with FFA post isolation and left to recover overnight prior to serum starvation, and then treated with KP-10 (R&D Systems™) or TAK-448 (MedChemExpress™). TGs were measured using the triglyceride quantification kit (MBL™ international Catalog # JM-K622-500).

M. Immunofluorescence

[0122] For immunofluorescence studies, cells were fixed in formalin, permeabilized with Triton™ X, and stained as described. Cells were incubated with KISS1 Antibody (EMD Millipore™, 1:250) followed by goat anti Rabbit- AF555 (Invitrogen™; 1:400). Nuclei were stained with Hoechst™ (Invitrogen™; 1:10000). Images were acquired using a Zeiss™ LSM 700 laser scanning microscope.

N. Patient blood collection and plasma kisspeptin measurement

[0123] The study has been approved by the Institutional Review Board at Rutgers University and all study participants (males) provided written consent. Individuals with chronic medical conditions that may affect glucose or lipid metabolism including active malignancy, HIV infection, hepatitis B, hepatitis C, alcoholism, chronic pancreatitis, active viral/bacterial infection, severe cardiac or respiratory failure were excluded. Plasma KP immune-reactivity in healthy subjects and patients with fatty liver (NAFLD, N=16) or NASH (N= 8) was determined. NAFLD diagnoses were based on elevated AST and ALT levels in the absence of other causes of liver disease as well as the presence of hepatic steatosis on ultrasound. NASH diagnoses were based on histologic analysis revealing macrovesicular steatosis, lobular and portal inflammation and fibrosis. Briefly, blood (5 mL) was collected in BD Vacutainer K2 EDTA tubes (VWR International) from subjects recruited from subspecialty clinics at Robert Wood Johnson Medical School in New Brunswick, NJ. Blood was centrifuged for 10 minutes at 1210 xg and plasma was frozen immediately for storage.

Plasma KP immune-reactivity was measured using a commercial Kisspeptin ELISA.

O. Immunohistochemistry

[0124] Mouse livers were processed for histology by the Research Pathology Services at Rutgers University. Oil Red O staining was performed on cryostat sections of the frozen liver tissues to detect neutral lipids. Paraffin sections of healthy human liver were purchased from OriGene Technologies™, Inc. (MD, USA). Paraffin sections from NASH/NAFLD patients were obtained from archived liver tissue deposited at Robert Wood Johnson University Hospital Pathology lab after diagnosis was confirmed by a pathologist. Following deparaffinization and heat induced antigen retrieval, slides were incubated with the rabbit polyclonal anti-GPR54 (Abeam™, abl37483; 1:1000), followed by ImmPRESS™ HRP Anti-Rabbit IgG (Peroxidase) Polymer Detection Kit (Vector Laboratories™).

P. Oxygen Consumption Rate (OCR)

[0125] OCR was measured using an Agilent Seahorse Biosciences™ extracellular flux analyzer (XFe24) as per the manufacturer’ s protocol using isolated primary mouse hepatocytes and human hepatic HepaRG cells. Briefly, cells were seeded at 2 x 10 ⁴ cells per well in XF24 plates in 500 pL William’s E Media (10% FBS, 200 nM dexamethasone, 1% Penstrep, and 2 mM glutamine) and were preincubated with 100 mM BSA-PAL or BSA +/- TAK-448 (3 nM) overnight at 37 °C and 5% CO2. Cells were serum starved for 1 hour prior to the assay. Basal OCR measurements were made in Seahorse™ XF media with 0.5 mM glucose and 0.5 mM L-camitine, treated with TAK-448 (3 nM) or PBS. The results were analyzed using Wave software (Agilent™ Technologies).

Q. Statistical Analysis.

[0126] Statistical significance between two groups was determined by unpaired two-tailed Student’s t test. For comparison among multiple groups, one-way analysis of variance followed by Dunnett’s multiple comparisons test was used. P value <0.05 is considered to be statistically significant. Graphs were generated with GraphPad™ Prism version 8.3.1 (San Diego, CA).

Example 2: Initial Studies: Kisspeptin analog (TAK-4481 administration protects against NAFLD (fatty liver and its progression to NASH) and prevents the development of insulin resistance in a high fat diet-induced pre-clinical mouse model of NAFLD.

[0127] C57BL/6J mice fed high fat diet (HFD) or control regular diet (RD) for 12 weeks (4- 5/group). TAK-448 (TAK) or Vehicle (Veh i.e., PBS controls) were administered for 4 weeks using an ALZET mini-osmotic pump implanted subcutaneously. See FIG. 1 for results. Steatosis is shown by hematoxylin and eosin stained mouse livers (lipid accumulation, small white droplets, arrowheads) and by Oil Red O staining of lipids (grey dots) in control livers (FIG. 1A). This was prevented in the TAK-448 treated group (FIG.

1 A). FIG. IB through FIG. 1G show the endpoint liver triglycerides (TGs), endpoint blood TGs, blood free fatty acids, blood glycerol, body weight, epididymal white adipose tissue fat accumulation, and inguinal white adipose tissue fat accumulation, respectively, are all decreased by TAK-448 administration. TAK-448 treatment prevented the rise in fasting glucose (measure of gluconeogenesis by liver) and prevented glucose intolerance and insulin resistance, as measured by a glucose tolerance test (GTT) or insulin tolerance tests (ITT), respectively. See FIG. 1H through FIG. 1J (black circles) vs controls (open circles). *, p<0.05; student t-test or One-way ANOVA and Dunnett’s post-hoc test. TAK-448 can be administered to delay or prevent disease progression in (1) and NAFLD patients (with or without Type II diabetes) and (2) NASH patients.

Example 3: TAK-448 Treatment Does Not Alter Food Intake in a Mouse Model of NAFLD. [0128] To determine the effect of enhanced KISS1R signaling on the development of NAFLD, wild-type C57BL6J mice (4 weeks of age) were placed on either RD or HFD for 6 weeks. Wild type ice on HFD gained weight (FIG. 2A) and developed insulin resistance resulting in elevated fasting glucose levels prior to TAK-448 (diabetes; FIG. 2B). Mice (littermates, with similar body weights) were then infused with vehicle (PBS) or a KP-analog (TAK, 0.3 nmol/hour), and further maintained on RD/HFD for another 4 weeks. As expected, HFD control (VEH) mice had significantly higher body weights compared to RD (VEH) control mice (FIG. IE). However, among the HFD mice, TAK-treated mice had a significantly lower body weight than VEH controls and lower fasting glucose levels compared to VEH group controls (FIG. IE); these changes occurred without a change in food intake (FIG. 2C). Consistent with these phenotypes, HFD TAK-treated mice were glucose tolerant (FIG. II) and insulin sensitive (FIG. 1J) compared to HFD controls.

Example 4: Kisspeptin-analog (TAK-448) Treatment Lowers Liver Enzyme (ALT) and Circulating Triglycerides and Free Fatty Acids levels, and Decreases White Adipose Tissue Mass in a High Fat Diet (HFD)-Induced Pre-clinical Mouse Model of NAFLD.

[0129] In addition to its striking effects on liver triglyceride accumulation and glucose homeostasis, TAK-448 treatment in HFD-fed mice also protected against a rise in ALT, a clinical marker of fatty liver disease (see FIG. 3A) and decreased blood cholesterol (see FIG. 3B) and glycerol (see FIG. 3C). CLAMS analysis further revealed that there were no differences in energy production or respiratory exchange ratio (RER) between treated and untreated mice (FIG. 4A and FIG. 4B).

[0130] Mechanistically, TAK treatment under HFD conditions significantly reduced the hepatic expression of key regulators of TG synthesis and fat synthesis such as PPARy, CD36 and MOGAT1 (FIG. 5A; FIG. 5B; FIG. 6A; FIG. 6B; FIG. 6C). Furthermore, TAK treatment induced phosphorylation of AMPK in the liver (FIG. 7; FIG. 8A), which upon activation inhibits PPARy transcription. AMPK activation also inhibits lipid synthesis by the acute inhibition of glycerol- 3 -phosphate acyltransferase (GPAT) activity and by negatively regulating SREBP1 transcription. Gpam (encodes GPAT) expression was significantly reduced in TAK treated livers (FIG. 5A), which could lead to the subsequent decrease in GPAT activity. Although the reduction in Srebfl was not significant, there was a significant decrease in its downstream target, Fasn (FIG. 5B; FIG. 8B). TAK treatment reduced the expression of Lfabpl and Gykl, important regulators of lipogenesis (FIG. 5A).

[0131] Finally, TAK-treated livers had lower levels of pro-inflammatory genes (Ip 10, Mcpl FIG. 9A), as well as reduced levels of markers for fibrosis ( Cola2 , Acta2 FIG. 9B) and oxidative stress ( Ucp2 , Gss FIG. 9B). Overall, the data suggest that in vivo TAK treatment protects against steatosis, by downregulating lipid synthesis via AMPK activation and this attenuates the development of NAFLD.

[0132] Phosphorylation of ACC reduces its activity, thereby inhibiting de novo lipogenesis (see FIG. 3 IB; FIG. 32B ). Hepatocytes isolated from RD liver KISS1R knock-out (LKO) mice demonstrated elevated levels of CD36, FAS, PPARy, and MOGAT1 (see FIG. 33A, FIG. 33B; FIG. 34A through FIG. 34D). Collectively, based on the data, we suggest that activation of KISS1R negatively regulates hepatic lipid content by activating AMPK, which then inhibits de novo lipogenesis, in addition to inhibiting PPARy (a key regulator of triglyceride synthesis) and its downstream signaling pathways (see FIG. 40).

[0133] FIG. 40 is an updated working model showing signaling pathway by which KISS1R activation inhibits progression to NASH (see dashed arrow). Activation of KISS1R by kisspeptin (KP) analog (TAK-448) activates the master energy sensor (AMPK), phosphorylating it. Activated AMPK then inhibits lipogenesis (formation of fat) by phosphorylating its downstream target enzyme, ACC resulting in its inhibition, and thereby inhibiting lipogenesis. This also results in activation of a key enzyme, CPT1, in mitochondria that promotes beta-oxidation of fatty acids, resulting in the breakdown of fat. Additionally, activation of AMPK inhibits triglyceride (TG) synthesis by reducing the activity and expression of transcription factor, PPAR-gamma that regulates the expression of many enzymes in TG synthesis pathway. Overall, this leads to a decrease in fat accumulation in the liver, thus inhibiting NAFLD and its progression to NASH and fibrosis. Example. 5: TAK-448 Administration Inhibited the Expression of Key Regulators of Hepatic Triglyceride Synthesis and de novo Lipogenesis.

[0134] FIG. 10 presents data relating to the expression of the indicated genes (regulators of triglyceride synthesis and fat formation (lipogenesis)) by qPCR analysis. * p< 0.05 versus control; Student’s unpaired t-test. These data show that TAK-448 treatment reduces the expression of key regulators of hepatic triglyceride (TG) synthesis and de novo lipogenesis. For each gene, there is a significant decrease in expression (what genes are, what they are involved in), therefore TAK-448 treatment can be used to lower fat in livers of patients. Example 6: TAK-448 Administration Inhibited the Expression of Key Regulators of Hepatic Inflammation.

[0135] Expression of indicated key genes in regulation of inflammation (macrophage inflammatory protein ( Mip2 ), chemokines, interferon gamma- induced protein 10 (Ip 10), interleukin 1 alpha (Ilia), proinflammatory cytokines tumor necrosis factor (TNF)-a ( Tnfa ), monocyte chemoattractant protein ( Mcpl ), and interleukins 1 alpha (Ilia) and 1 beta ( Illb )) was examined by qPCR analysis and the results are presented in FIG. 11. * p< 0.05 versus control; Student’s unpaired t-test. The results show that TAK-448 treatment reduces the expression of these key regulators of hepatic inflammation.

Example 7: TAK-448 Administration Inhibited the Expression of Key Regulators of Hepatic Fibrosis.

[0136] Expression of indicated genes that regulate fibrosis by qPCR analysis (collagen ( Colla2 ), smooth muscle actin (. Acta2 ) and transforming growth factor beta ( TGFb )) is shown in FIG. 12. * p< 0.05 versus control; Student’s unpaired t-test. The results show that this kisspeptin analog reduces the expression of key regulators of hepatic fibrosis.

Example 8: TAK-448 Administration Increased the Expression of Genes Regulating Mitochondrial and Peroxisomal Beta- Oxidation of Fat.

[0137] TAK-448 treatment increased expression of Cptla and Cpt2, rate-limiting enzymes for mitochondrial fatty acid transportation and also increased the expression of acyl- coenzyme A oxidase (AOX), which regulates the rate-limiting step of peroxisomal b- oxidation of fatty acids. * p< 0.05 versus control; Student’s unpaired t-test. See FIG. 13, which shows the expression of indicated genes by qPCR analysis. In summary, TAK-448 (kisspeptin analog) treatment increased the expression of hepatic genes regulating mitochondrial and peroxisomal beta-oxidation of fat, which would result in an increase in the breakdown of fat. Example 9: Hepatic knock-out (KQ) of Kissl r promotes weight gain, hepatic steatosis and lipid accumulation in a mouse model of NAFLD.

[0138] Hepatic Kissl r KO (LKO) were generated by crossing a Kisslr fl/fl mouse to Alb- Cre mouse (Jackson Labs™). Littermate controls (Kisslr fl/fl) and Kisslr KO mice (3 weeks old, 10/group) were fed regular diet (RD) or high fat diet (HFD) diet for 20 weeks. LKO mice had significant increase in body weight (FIG. 14A through FIG. 14C), despite no changes in food intake (FIG. 14). H&E stained mouse livers showed a striking increase in steatosis in the LKO livers compared to controls (all on HFD) (FIG. 15A). In contrast, steatosis was not observed in livers of animals maintained on RD (see FIG. 15B, which shows healthy liver). The boxed area is magnified in the lower image (FIG. 15B). FIG. 16 shows elevation of liver triglycerides in LKO (HFD) mice, compared to controls (CTRL) also on HFD. *, p<0.05 Student t-test or One-way ANOVA and Dunnett’s post-hoc test.

Example 10: Generation of Hepatic KisslR Knockouts To Determine the Role of Hepatic KISS1R in Regulating NAFLD.

A. Hepatic KISS1R deficiency aggravates hepatosteatosis in obese, insulin resistant mice. [0139] To test whether or not hepatic KISS 1/KISS 1R is involved in the pathogenesis of NAFLD, hepatic Kiss 1/Kiss 1 r expression was measured in a diet- induced mouse model of NAFLD. After 4-week old wild-type C57BL/6 mice were fed a high fat diet (HFD) for 8 weeks, Kissl and Kisslr mRNA levels were significantly increased in the livers. See FIG. 17, which shows the relative RNA expression of Kissl and Kisslr by RT-qPCR normalized to Rpll3a RNA expression in C57BL6 male mice on regular diet (RD) or high fat diet (HFD) for 8 weeks. Thus, high fat diet (HFD) induces the expression of kisspeptin (KISS1) and kisspeptin receptor (KISS1R) gene expression.

[0140] Next, to investigate a role for KISS1R in regulating hepatic lipid metabolism, a liver- specific knockout of Kissl r (LKO) was generated. Analysis of the LKO mice showed that Kissl r expression, but not Kissl, was significantly reduced. See FIG. 18A. LKO mice and their littermate controls were then placed on control regular diet (RD) or HFD. LKO and control mice fed a RD showed no difference in body weight (FIG. 18B). Differences in RER (respiratory exchange rate) and ambulatory activity were not observed between groups (see FIG. 18C and FIG. 18D).

[0141] Interestingly, LKO mice on HFD exhibited lower heat expenditure (indicative of a lower metabolism) compared to controls (FIG. 19A; heat expenditure assessed by CLAMS). Serum alanine transaminase (ALT) levels (a clinical marker of fatty liver disease) were elevated in both HFD groups compared to RD, indicating HFD-induced hepatocellular injury (FIG. 19B).

[0142] LKO mice also exhibited a decrease in muscle mass (FIG. 20A (gastrocnemius muscle) and FIG. 20B (tibialis anterior muscle)), and an increase in inguinal white adipose tissue, although no changes were observed in epididymal white adipose tissue compared to controls on HFD (see FIG. 20C and FIG. 20D). The increase in liver TGs in the LKO HFD mice suggest that hepatic KISS1R plays a protective function in the liver against steatosis.

B. Hepatic KISS1R deficiency upregulates genes regulating lipo genesis and free fatty acid (FFA) uptake.

[0143] To elucidate the mechanism underlying hepatic lipid accumulation in LKO mice, the levels of hepatic regulators of fatty acid uptake (the fatty acid translocase, cluster of differentiation ( Cd36 ), liver fatty acid-binding protein, ( Lfabpl )), and lipogenesis (peroxisome proliferator-activated receptor g (PPARy, encoded by Pparg), sterol regulatory element binding protein- 1 (SREBP1, encoded by Srebfl ) and its downstream target fatty acid synthase (FAS, encoded by Fasn)) were measured. Under HFD conditions, there was a significant increase in key genes regulating fat formation (FIG. 21 A; relative mRNA expression of indicated genes in liver samples (HFD) normalized to Rpll3a mRNA expression) except for Acaca, which encodes acetyl-CoA carboxylase 1 (ACC1, which catalyzes the first committed step of de novo fatty acid synthesis) was increased but not significantly. Protein levels of PPAR-g and its downstream gene target, CD36, as well as the levels of FAS were also significantly higher in the HFD LKO livers compared to controls (FIG. 21A; FIG. 22A, FIG. 22B, and FIG. 22C). Mean ± SEM shown; Student’s unpaired t- test, *p < 0.05 compared to control group.

[0144] Additionally, LKO livers exhibited suppressed phosphorylation of AMPK (FIG. 21B; FIG. 22D), a protein kinase that when activated inhibits de novo lipogenesis by negatively regulating Srebfl, and its downstream gene targets Acaca and Fasn.

Example 11: Hepatic KisslR Knockouts Exhibit Increased Expression of Genes Regulating Triglyceride Synthesis and Enhanced Liver Lipids Levels.

[0145] Triglyceride (TG) synthesis requires glycerol 3-phosphate (G3P), which can be formed by two methods: (a) the glycerol kinase (GYK)-dependent phosphorylation of glycerol and (b) by the glycerol 3 -phosphate dehydrogenase (GPDl)-dependent reduction of dihydroxyacetone phosphate. See FIG. 23 A, a schematic showing hepatic triglyceride (TG) synthesis pathway; molecules in bold are upregulated in HFD LKO and control (CTRL) livers. An analysis of the livers from the HFD LKO mice revealed a significant increase in the hepatic expression of Gykl mRNA and protein levels (FIG. 23B, FIG. 21B, and FIG. 24). Liver Kisslr knock-out (LKO) mice on HFD exhibited elevated levels of genes regulating triglyceride synthesis (see FIG. 23B).

[0146] Glycerol enters the liver primarily via aquaglyceroporins (AQP) such as AQP3 and AQP9 (see FIG. 23A). Aqp9 mRNA levels were significantly upregulated in LKO HFD mice livers, whereas Aqp3 levels remain unchanged (FIG. 23B). Many enzymes regulating TG synthesis including GPAT1 (encoded by Gpam) which catalyzes the rate limiting step in TG synthesis, diacylglycerol (DAG) acyltransferase 2 ( Dgat2 ) that acetylates DAG to form TG, and monoacylglycerol acyltransferase 1 ( Mogatl ) that coverts monoacylglycerol to diacylglycerol (see FIG. 23B), the direct precursor of TG was also upregulated in LKO HFD livers (see FIG. 23 A, showing that LKO mice on HFD exhibit elevated levels of genes regulating triglyceride synthesis). Taken together, this demonstrates that LKO mice displayed elevated levels of genes regulating TG synthesis.

[0147] In order to uncover metabolic differences contributing to the distinct phenotypes observed in LKO mice under HFD conditions, a global, untargeted metabolomic analysis of LKO and control livers was conducted. This revealed that various lipids including TGs, DAG, and phosphatidylcholine were significantly upregulated in HFD LKO livers (see FIG. 25A, a volcano plot showing an increase in liver lipid metabolites in LKO mice on HFD by mass spectroscopy). Similar observations have also been seen in patients with NAFLD and NASH. LKO mice also exhibited other changes. These included high levels of ceramides, phosphatidylglycerol and cardiolipin. The inhibition of ceramide synthesis was reported to attenuate hepatic steatosis and fibrosis, while phosphatidylglycerol, a mitochondrial phospholipid, is implicated in multiple metabolic diseases including hepatosteatosis. Cardiolipin is a phospholipid that is essential for optimal mitochondrial function and alterations contribute to mitochondrial dysfunction in multiple tissues including insulin resistance and NAFLD.

[0148] Since the data revealed that the loss of hepatic KISS1R resulted in an increase in lipid accumulation in hepatocytes under HFD, possibly via an upregulation of PPARy and its downstream gene targets, we asked whether this also occurred in livers of LKO mice maintained on RD. Interestingly, LKO mice maintained on RD did not develop steatosis or accumulate TGs. However, Pparg was significantly upregulated with no significant changes in Mogatl, Cd36, or Srebfl (see FIG. 25B). This suggests that a potential mechanism by which KISS1R signaling regulates hepatic lipogenesis is via regulation of PPARy.

Example 12: Hepatic Kisslr KO mice are glucose intolerant and insulin resistant.

[0149] Since insulin resistance plays an important role in the pathogenesis of NAFLD, metabolic tests were performed to examine the effect of loss of hepatic KISS1R on blood glucose levels. Results showed that compared to HFD controls, HFD LKO mice had significantly higher fasting glucose levels, indicative of elevated gluconeogenesis (see FIG. 26A). They were also glucose intolerant (FIG. 26B and FIG. 26C) and insulin resistant (FIG. 26D and FIG. 26E).

[0150] Additionally, there was increased expression of key hepatic genes regulating gluconeogenesis, such as G6pc (which converts glucose-6-phosphate to glucose at the terminal step in gluconeogenesis), Pckl (which converts oxaloacetate to phosphoenolpyruvate), and hepatic glucose transporter GLUT2 encoded by Slc2a2 in the LKO HFD livers (FIG. 26F).

[0151] NAFLD can progress to NASH, a state associated with increased inflammation, fibrosis and oxidative stress in the liver. We observed that in LKO mice, after 20 weeks of HFD, there was an upregulation of various genes regulating inflammation associated with NAFLD such as cytokines macrophage inflammatory protein 2 ( Mip2 ), interleukin 1 isoforms, ILla and Iίb (encoded by Ilia and Illb ) and chemokines interferon gamma- induced protein 10 (IplO) and monocyte chemoattractant protein ( Mcpl ). See FIG. 26G. [0152] LKO mice also exhibited an increase in genes involved in NASH, that are upregulated in early stage of fibrosis. These included collagen ( Colla2 ) and transforming growth factor b ( Tgfbl ). An increase in smooth muscle actin ( Acta2 ) and tissue inhibitor of metalloproteinase 1 ( Timpl ) was also observed but this did not reach significance (see FIG. 26H). Additionally, there was an increase in markers for oxidative stress ( Sodl , Sod2, Gss ) (see FIG. 261). Together, these findings suggest that loss of hepatic KISS1R signaling exerts a deleterious effect on the liver, promoting the NAFLD phenotype.

Example 13: KISS1R Knockout (LKO) is Selective in the Liver.

[0153] Expression of the genes (indicated in FIG. 27) by RT-qPCR in HFD-fed CTRL and LKO mice in various organs, showing specificity of KISS1R knockdown, selectively in the liver. * p< 0.05 versus control; Student’s unpaired t-test.

Example 14: Hepatic KISS1R Signaling Negatively Regulates Hepatic PPAR-gamma Expression and Activity. [0154] Transcription factor PPAR-gamma is a key regulator of lipogenesis that is induced in steatotic (fatty) livers of NAFLD patients and experimental mouse models. FIG. 28 presents representative western blots showing reduced phosphorylation of PPAR-gamma at an inhibitory site (Serine- 112), despite elevated expression of PPAR-gamma in livers from CTRL and LKO mice on HFD. See FIG. 28A. Conversely, FIG. 28B shows that administration of TAK-448 decreased PPAR-gamma expression in mice liver and induced its phosphorylation at Serine- 112, resulting in a decrease in the expression of PPAR-gamma target genes, MOGAT1, CD36 and FAS compared to Vehicle (PBS)-treated controls. See FIG. 5B.

Example 15: Isolated Primary Mouse Hepatocytes: TAK-448 Treatment Directly Inhibits Triglyceride Accumulation by Inhibiting the Expression of Key Regulators of de novo Lipogenesis and Triglyceride Synthesis.

[0155] Since the data revealed that KISS1R signaling inhibits steatosis in vivo, a direct effect of TAK-448 on hepatic lipogenesis was examined using primary mouse hepatocytes. FIG. 29A presents a representative confocal image of endogenous kisspeptin (KISS1 protein, see arrows) immunostaining in primary hepatocytes. Scale bar, 50 mM. Hepatocytes were cultured in the presence or absence of a mixture of free fatty acids (FFAs: 150 pM palmitate and 150 pM oleate) conjugated to bovine serum albumin (BSA) carrier. KP-10 (100 nM) or TAK-448 (3 nM) treatment of FFA loaded hepatocytes isolated from controls mice resulted in decreased TG accumulation (see FIG. 29B). However, FIG. 29C shows TAK-448 and KP- 10 failed to suppress triglyceride accumulation in hepatocytes isolated from hepatic KISS1R knockout (LKO) mice. TAK-448 treatment (8 hours) also reduced the expression of genes regulating de novo lipogenesis and triglyceride (TG) synthesis in primary mouse hepatocytes isolated from C57BL6 male mice cultured in the presence or absence of a mixture of free fatty acids (FFAs: 150 pM palmitate and 150 pM oleate) conjugated to bovine serum albumin (BSA) carrier (FIG. 30). Kisspeptin (KP) or TAK treatment for 8 hours reduced the basal expression of de novo lipogenic genes (FIG. 31 A) and stimulated phosphorylation of AMPK and its downstream target, ACC (FIG. 3 IB), which shows that TAK-448 treatment activated AMPK in isolated primary hepatocytes to thereby inhibit fat synthesis. FIG. 31C shows that KISS1R expression is depleted n primary hepatocytes isolated from LKO mice. See also FIG. 32, which shows densitometric analyses of the representative western blots in FIG. 3 IB showing the effect of kisspeptin treatment on phosphorylation of AMPK and its downstream substrate ACC in primary mouse hepatocytes (n=4). Example 16: Isolated Primary Mouse Hepatocvtes: Increased Expression of Key Regulators of de novo Lipogenesis and Triglyceride Synthesis in hepatocvtes isolated from KISS1R knockout mice.

[0156] Hepatocytes isolated from KISS1R knockout mice demonstrated elevated levels of proteins regulating fat formation, such as CD36, FAS, PPARy, and MOGAT1 (see FIG. 33A, FIG. 34A through FIG. 34D showing the densitometric analysis of the blots in FIG. 33A). Hepatocytes isolated from KISS1R knockout mice also demonstrated elevated levels of genes regulating fat formation (FIG. 33B).

Example 17: Isolated Primary Mouse Hepatocvtes: TAK-448 Treatment Increases Mitochondrial Beta Oxidation of Free Fatty Acids.

[0157] FIG. 35 shows the oxygen consumption rate (OCR) in hepatocytes treated with 100 mM Palmitate (PA) or BSA Vehicle control) with or without TAK-448 (3 nM) or CPT1 inhibitor, Etomoxir (ETO); CPT1 is a key regulator of mitochondrial beta-oxidation. Representative OCR trace using Seahorse analyzer are shown in FIG. 35A following sequential treatment with 2.5 mM oligomycin (Oligo), 3 pM carbonyl cyanide-4 (trifluoromethoxy) phenylhydrazone (FCCP), an uncoupler of mitochondrial oxidative phosphorylation and 2.5 pM of Rotenone and antimycin A (R +A), complex I and III inhibitors. This figure shows that TAK-448 increases mitochondrial fatty acid oxidation (FAO). FIG. 35B shows that TAK-448 increases basal respiration and FIG. 35C shows that TAK-448 increases ATP production. Mean ± SEM shown. Student’s unpaired t-test, * p< 0.05 vs controls; One-way ANOVA followed by Dunnet’s post-hoc test. The results show that TAK-448 (kisspeptin analog) treatment directly increases mitochondrial beta-oxidation of free fatty acids ie promoting their breakdown in isolated primary mouse hepatocytes. Example 18: Human Hepatocvtes: TAK-448 Treatment Increases Mitochondrial Beta Oxidation of Free Fatty Acids.

[0158] FIG. 36A presents Seahorse™ analyzer traces of oxygen consumption rate (OCR) in human hepatic HepaRG cells following sequential treatment with 1 pM oligomycin (Oligo), 1 pM FCCP and 0.5 pM of rotenone and antimycin A (R+A), respectively. The cells were treated with 100 pM Palmitate (PA) or BSA in the presence or absence of TAK-448 (3 nM). TAK-448 treatment increases the breakdown of fat in human hepatocytes. FIG. 36B shows TAK-448 increases basal respiration and FIG. 36C shows that TAK-448 increases ATP production in human hepatocytes. Mean ± SEM shown. Student’s unpaired t-test, or one way ANOVA followed by Dunnett’s post-hoc test; *p < 0.05 compared to controls. Thus, the results show that TAK-448 (kisspeptin analog) treatment increases mitochondrial b-oxidation of free fatty acids in human hepatic cells.

Example 19: Human Hepatic Stellate LX-2 Cells: TAK-448 Treatment Inhibits Proliferation and Decreases Markers of Fibrosis.

[0159] Two hundred thousand LX-2 cells were seeded into each well and treated with TAK- 448 (3 nM) or Vehicle (PBS) for 48 hours, then counted using hematocytometer. See results in FIG. 37A. Cells were treated with TAK-448 (3 nM) for 48 hours. Then, changes in gene expression for markers for fibrosis (smooth muscle actin: ACTA and collagen: COL1A1) were measured by RT-qPCR. Student’s unpaired t-test, *p < 0.05; N=3. See results in FIG. 37B. These results show that TAK-448 inhibits human hepatic stellate LX-2 cell proliferation and fibrotic gene expression.

Example 20: Human NASH Biopsy Section: Endogenous Kisspeptin Receptors are localized to Hepatic Stellate Cells.

[0160] The localization of endogenous kisspeptin receptor (KISS1R) and stellate cell marker (desmin) in human NASH biopsy section was examined. Nuclei were stained using Hoechst™. Infiltration of immune cells seen on the left are negative for staining for KISS1R (see FIG. 38A, arrows). Areas where KISS1R co-localizes with desmin (molecular marker for hepatic stellate cells) appear as bright white (in Overlay, FIG. 38D, arrows).

Example 21: KISS1 and Kisspeptin Receptor (KISS1R) Expression and Plasma Kisspeptin level is Increased in Human NAFLD.

[0161] FIG. 39A shows the relative mRNA expression of human KISS1 and KISS1R by RT- qPCR normalized to TBP in patient liver biopsies. KISS1 and KISS1R gene expression is elevated in NAFLD/NASH patients. FIG. 39B shows representative western blots. Mean ± SEM shown, student’s unpaired t-test, *p < 0.05 compared to controls. FIG. 39C and FIG. 39D shows densitometric analysis of the western blots from FIG. 39B. FIG. 39E shows representative results from immunostained images of endogenous human KISS1R expression in adult liver, using rabbit polyclonal anti-human KISS1R; scale bars: 80 pm. KISS1R protein expression is elevated in patient livers biopsy from NAFLD/NASH patients. FIG. 39F shows plasma kisspeptin (KP) levels (pmol/L; mean ± SD) measured by radioimmunoassay in human subjects. Kisspeptin (KISS1) protein expression is elevated in NAFLD patient livers. Table 8, below shows the clinical characteristics of the male subjects in FIG. 39A, B. Statistical analysis was done using a nonparametric Kruskal-Wallis test. Error bars: SD. Plasma kisspeptin levels are elevated in NAFLD and NASH patients compared to levels in healthy subjects.

Table 8. Male Subject Clinical Characteristics.

Data are presented as mean values ± SD. h: p<0.05 significance comparted to healthy d: p<0.05 significance compared to T2D. s: p<0.05 significance compared to NASH.

Example 22: Mechanism of action of protective effects of TAK-448 in NAFLD.

[0162] These findings suggest that enhanced activation of KISS1R by TAK-448 negatively regulates hepatic lipid content by activating AMPK, which then inhibits lipogenesis and increases fatty acid oxidation, in addition to inhibiting PPARg and its downstream signaling pathways that regulate triglyceride synthesis. (See FIG. 40). This results in protecting against the development of fatty liver (steotosis) and its progression to NASH and fibrosis. In summary, the data presented here show that TAK-448 is a potent kisspeptin analog that protects against the development of fatty liver and its progression to NASH by activating AMPK and increasing the breakdown of fat in the mitochondria (i.e fatty acid oxidation).

REFERENCES

[0163] All references listed below and throughout the specification are hereby incorporated by reference in their entirety.

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