FIELD OF THE INVENTION:

The invention is in the field of cardiology, more particularly the invention relates to method and composition for stimulating O-GlcNAcylation during extracorporeal circulation.

BACKGROUND OF THE INVENTION:

O-GlcNAcylation is a form of post-translational protein modification. It involves attachment of the monosaccharide N-acetylglucosamine (GlcNAc) to serine and threonine residues in nuclear, mitochondrial and cytoplasmic proteins in different organisms. O- GlcNAcylation is a reversible process catalysed by O-GlcNAc transferase (OGT) and O- GlcNAcase (OGA) which adds and removes the GlcNAc moiety, respectively. O- GlcNAcylation plays an important role in many, if not all, cellular processes.

Extracorporeal circulation (ECC) is an essential component in critical care and cardiothoracic surgery with for example the cardiopulmonary bypass (CPB) (Reynolds and Annich, 2011), the extracorporeal membrane oxygenation (ECMO), the extracorporeal life support (ECLS) or the extracorporeal carbon di oxy de removal (ECCO2R) but is associated with complex adverse event (Al-Fares et al., 2019). It comprises microcirculatory and metabolic disorders, activation of the complement, kinin, fibrin pathways and inflammation (Casey, 1993; Esper et al., 2014) and bacterial endotoxins translocation from the patient's digestive system (Kats et al., 2011) potentially leading to organs dysfunction and poor patients’ outcomes. Unfortunately, multi-organ dysfunction occurs relatively frequently, to varying degrees (Esper et al., 2014) and no real prevention means, or treatment are available. A gap still remains to improve patients’ outcomes and there is a need to study the pathophysiological mechanisms. Animal model mimicking pathophysiology of CPB or ECMOZECLS and reproducing multiple organ injuries are needed.

CPB is a common procedure to maintain body perfusion during cardiac surgery. It is associated with a systemic inflammatory response, hemostasis and circulatory dysfunction that can lead to organ dysfunction and seldomly to death. Previous studies shows that glutamine reduces myocardial damage after coronary revascularization under cardiopulmonary bypass (Chavez-Tostado et al, 2017. Lomivorotov et al, 2011), or that pyruvate modifies metabolic flux and nutrient sensing during ECMO (Ledee et al, 2015). However, these studies do not teach or suggest a direct relationship between an increase in O-GlcNAcylation levels and a cardioprotective effect. O-GlcNAcylation is a post-translational modification modulated in response to stress in different acute and chronic situations. The inflammation and tissue stress consecutive to CPB are associated with an increase in blood O-GlcNAcylation levels 5 hours after CPB. Thus, there is a need to reduce the inflammation and tissue stress during a CBP.

SUMMARY OF THE INVENTION:

The invention relates to a method for increasing O-GlcNAcylation levels in a subject having or is susceptible to have an extracorporeal circulation comprising administering said subject with a therapeutically effective amount of a compound that increases O-GlcNAcylation levels. In particular, the invention is defined by the claims.

DETAILED DESCRIPTION OF THE INVENTION:

Inventors observe that the NButGT treatment increases the O-GlcNAcylation levels of cardiac proteins (p<0.05) (Figure 1). Mean arterial pressure decreases 5 hours after ECC procedure compared to the sham group (sham: 95.7 ± 3.7; ECC: 69.8 ± 7.7; mmHg; p<0.05) (Figure 3 A). The NButGT treatment tends to increase the mean arterial pressure compared to the ECC group (NButGT: 90.8 ± 10.3; mmHg; p = 0.11) (Figure 3 A). ECC procedure is associated with an organism injury with an increase in lactates, creatinine, blood urea nitrogen and bicarbonates levels 5 hours after ECC procedure (p<0.05) (Figure 3B-3E). NButGT treatment tends to reduce lactates and creatinine levels and decreases blood urea nitrogen and arterial bicarbonates 5 hours after ECC procedure (p<0.05) (Figure 3B-3E).

Accordingly, in a first aspect, the invention relates to a method for increasing O- GlcNAcylation levels in a subject having or is susceptible to have an extracorporeal circulation comprising administering said subject with a therapeutically effective amount of a compound that increases O-GlcNAcylation levels.

In other words, the invention relates to a method for reducing or preventing adverse effect of extracorporeal circulation in a subject comprising administering to said subject a therapeutically effective amount of a compound that increases O-GlcNAcylation levels.

In other words, the invention relates to a compound that increases O-GlcNAcylation levels for use for reducing or preventing adverse effect of extracorporeal circulation in a subject in need thereof. As used herein, the term “extracorporeal circulation” refers to the circulation of blood outside of the body through a machine that temporarily assumes an organ's functions, for example, through a heart-lung machine or artificial kidney. In a particular embodiment, the extracorporeal circulation is performed during apheresis, autotransfusion, hemodialysis, hemofiltration, plasmapheresis, extracorporeal carbon dioxide removal, extracorporeal cardiopulmonary resuscitation, extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass.

As used herein, the term “adverse effect of extracorporeal circulation” has its general meaning in the art and refers to potential complication caused by extracorporeal circulation. Typically adverse effects of circulation include but are not limited to microcirculatory and metabolic disorders, activation of the complement, kinin, fibrin pathways and inflammation (Casey, 1993; Esper et al., 2014) and bacterial endotoxins translocation from the patient's digestive system (Kats et al., 2011), which can lead to organs dysfunction and poor subject’s outcomes. Adverse effects of extracorporeal circulation include also organ failure and acute atrial fibrillation.

As used herein, the term “subject” refers to any mammals, such as a rodent, a feline, a canine, and a primate. Particularly, in the present invention, the subject is a human having or susceptible to have extracorporeal circulation. In other words, the subject is a human requiring or susceptible to requires an extracorporeal circulation.

As used herein, the term “increasing” refers to an increase in O-GlcNAcylation levels. In the context of the invention (extracorporeal circulation), an increase in O-GlcNAcylation levels allows to reduce circulating lactates, creatinin, blood urea nitrogen (BUN) and arterial bicarbonates.

As used herein, the term “O-GlcNAcylation levels” also known as O-N-acetyl glucosaminylation refers to a reversible posttranslational modification (PTM) that involves the addition of the monosaccharide P-D-Nacetylglucosamine to serine and threonine residues of proteins. Protein O-GlcNAcylation is added by O-GlcNAc transferase (OGT), and the O- GlcNAc group on proteins can be removed via the P-N-acetylglucosaminidase (O-GlcNAcase, OGA). O-GlcNAcylation is regulated dynamically by these two enzymes and by the intracellular concentration of UDP-GlcNAc, a product of glucose metabolism through the hexosamine biosynthetic pathway (HBP). As used herein, the term “compound that increases O-GlcNAcylation levels” refers to a natural or synthetic compound that has a biological effect to increase the levels of O- GlcNAcylation. More particularly, such compound is capable of reduce the production of lactates, creatinine and blood urea nitrogen (BUN).

In a particular embodiment, the compound that increases O-GlcNAcylation levels is an inhibitor of P-N-acetylglucosaminidase (OGA).

As used herein, the term “P-N-acetylglucosaminidase”, also known as OGA or O- GlcNAcase, has its general meaning in the art and refers to enzyme which hydrolyse N- acetylglucosamine-containing oligosaccharides and proteins.

As used herein, the term “inhibitor of P-N-acetylglucosaminidase” refers to a natural or synthetic compound that has a biological effect to inhibit the activity of OGA and thus increase the levels of O-GlcNAcylation.

In a particular embodiment, the inhibitor of P-N-acetylglucosaminidase is a peptide, peptidomimetic or a small organic molecule.

In a particular embodiment, the inhibitor of P-N-acetylglucosaminidase is is 1,2- dideoxy-2 ^z -propyl- a -d-glucopyranoso-[2, 1-D]- A 2-thiazoline (NButGT) and its derivatives. The CAS number of NButGT is 863918-55-2.

In a particular embodiment, the inhibitor of P-N-acetylglucosaminidase is (3aR,5R,6S,7R,7aR)-2-(ethylamino)-3a,6,7,7a-tetrahydro-5-(hy droxymethyl)-5H-Pyrano[3,2- d]thiazole-6,7-diol) (ThiametG) and its derivatives. The CAS number of ThiametGis 1009816- 48-1.

In a particular embodiment, the compound that increases O-GlcNAcylation levels is a peptide, peptidomimetic or a small organic molecule.

In a particular embodiment, the compound that increases O-GlcNAcylation levels is a small organic molecule. The term “small organic molecule” refers to a molecule of a size comparable to those organic molecules generally used in pharmaceuticals. The term excludes biological macromolecules (e.g., proteins, nucleic acids, etc.). Preferred small organic molecules range in size up to about 5000 Da, more preferably up to 2000 Da, and most preferably up to about 1000 Da.

In a particular embodiment, the compound that increases O-GlcNAcylation levels is 1,2- dideoxy-2 ^z -propyl- a -d-glucopyranoso-[2, 1-D]- A 2-thiazoline (NButGT) and its derivatives. The CAS number of NButGT is 863918-55-2. In a particular embodiment, the compound that increases O-GlcNAcylation levels is (3aR,5R,6S,7R,7aR)-2-(ethylamino)-3a,6,7,7a-tetrahydro-5-(hy droxymethyl)-5H-Pyrano[3,2- d]thiazole-6,7-diol) (ThiametG) and its derivatives. The CAS number of ThiametGis 1009816- 48-1.

In a particular embodiment, the compound that increases O-GlcNAcylation levels is a compound that increases the Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc).

As used herein, the term “UDP-GlcNAc” refers to a nucleotide sugar and a coenzyme in metabolism. It is synthesized de novo from glucose by the hexosamine synthesis pathway (HBP), but can also be produced via salvage pathways.

In a particular embodiment, compound that increases O-GlcNAcylation levels is a compound that increases the hexosamine biosynthesis pathway flux that bypasses glutamine/fructose-6-phosphate amidotransferase 2.

In a particular embodiment, the compound that increases O-GlcNAcylation levels is glutamine or glucosamine.

As used herein the terms "administering" or "administration" refer to the act of injecting or otherwise physically delivering a substance as it exists outside the body (e.g., a compound that increases O-GlcNAcylation levels) into the subject, such as by mucosal, intradermal, intravenous, subcutaneous, intramuscular delivery and/or any other method of physical delivery described herein or known in the art. When a disease, or a symptom thereof, is being treated, administration of the substance typically occurs after the onset of the disease or symptoms thereof. When a disease or symptoms thereof, are being prevented, administration of the substance typically occurs before the onset of the disease or symptoms thereof.

A “therapeutically effective amount” is intended for a minimal amount of active agent which is necessary to impart therapeutic benefit to a subject. For example, a "therapeutically effective amount" to a subject is such an amount which induces, ameliorates or otherwise causes an improvement in the pathological symptoms, disease progression or physiological conditions associated with or resistance to succumbing to a disorder. It will be understood that the total daily usage of the compounds of the present invention will be decided by the attending physician within the scope of sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the disorder being treated and the severity of the disorder; activity of the specific compound 15 employed; the specific composition employed, the age, body weight, general health, sex and diet of the subject; the time of administration, route of administration, and rate of excretion of the specific compound employed; the duration of the treatment; drugs used in combination or coincidental with the specific compound employed; and like factors well known in the medical arts. For example, it is well within the skill of the art to start doses of the compound at levels lower than those required to achieve the desired therapeutic effect and to gradually increase the dosage until the desired effect is achieved. However, the daily dosage of the products may be varied over a wide range from 0.01 to 1,000 mg per adult per day. Typically, the compositions contain 0.01, 0.05, 0.1, 0.5, 1.0, 2.5, 5.0, 10.0, 15.0, 25.0, 50.0, 100, 250 and 500 mg of the active ingredient for the symptomatic adjustment of the dosage to the subject to be treated. A medicament typically contains from about 0.01 mg to about 500 mg of the active ingredient, preferably from 1 mg to about 100 mg of the active ingredient. An effective amount of the drug is ordinarily supplied at a dosage level from 0.0002 mg/kg to about mg/kg of body weight per day, especially from about 0.001 mg/kg to 7 mg/kg of body weight per day.

The compound that increases O-GlcNAcylation levels as described above may be combined with pharmaceutically acceptable excipients, and optionally sustained-release matrices, such as biodegradable polymers, to form pharmaceutical compositions.

Accordingly, in a second aspect, the invention relates to a pharmaceutical composition comprising the compound that increases O-GlcNAcylation levels as described above and excipients.

"Pharmaceutically" or "pharmaceutically acceptable" refer to molecular entities and compositions that do not produce an adverse, allergic or other untoward reaction when administered to a mammal, especially a human, as appropriate. A pharmaceutically acceptable carrier or excipient refers to a non-toxic solid, semi-solid or liquid filler, diluent, encapsulating material or formulation auxiliary of any type. The pharmaceutical compositions of the present invention for oral, sublingual, subcutaneous, intramuscular, intravenous, transdermal, local or rectal administration, the active principle, alone or in combination with another active principle, can be administered in a unit administration form, as a mixture with conventional pharmaceutical supports, to animals and human beings. Suitable unit administration forms comprise oral-route forms such as tablets, gel capsules, powders, granules and oral suspensions or solutions, sublingual and buccal administration forms, aerosols, implants, subcutaneous, transdermal, topical, intraperitoneal, intramuscular, intravenous, subdermal, transdermal, intrathecal and intranasal administration forms and rectal administration forms. Typically, the pharmaceutical compositions contain vehicles which are pharmaceutically acceptable for a formulation capable of being injected. These may be in particular isotonic, sterile, saline solutions (monosodium or disodium phosphate, sodium, potassium, calcium or magnesium chloride and the like or mixtures of such salts), or dry, especially freeze-dried compositions which upon addition, depending on the case, of sterilized water or physiological saline, permit the constitution of injectable solutions. The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions; formulations including sesame oil, peanut oil or aqueous propylene glycol; and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms, such as bacteria and fungi. Solutions comprising compounds of the invention as free base or pharmacologically acceptable salts can be prepared in water suitably mixed with a surfactant, such as hydroxypropylcellulose. Dispersions can also be prepared in glycerol, liquid polyethylene glycols, and mixtures thereof and in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms. The polypeptide (or nucleic acid encoding thereof) can be formulated into a composition in a neutral or salt form. Pharmaceutically acceptable salts include the acid addition salts (formed with the free amino groups of the protein) and which are formed with inorganic acids such as, for example, hydrochloric or phosphoric acids, or such organic acids as acetic, oxalic, tartaric, mandelic, and the like. Salts formed with the free carboxyl groups can also be derived from inorganic bases such as, for example, sodium, potassium, ammonium, calcium, or ferric hydroxides, and such organic bases as isopropylamine, trimethylamine, histidine, procaine and the like. The carrier can also be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), suitable mixtures thereof, and vegetables oils. The proper fluidity can be maintained, for example, by the use of a coating, such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. The prevention of the action of microorganisms can be brought about by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents, for example, sugars or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, for example, aluminium monostearate and gelatin. Sterile injectable solutions are prepared by incorporating the active polypeptides in the required amount in the appropriate solvent with several of the other ingredients enumerated above, as required, followed by filtered sterilization. Generally, dispersions are prepared by incorporating the various sterilized active ingredients into a sterile vehicle which contains the basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum-drying and freeze-drying techniques which yield a powder of the active ingredient plus any additional desired ingredient from a previously sterile-filtered solution thereof. Upon formulation, solutions will be administered in a manner compatible with the dosage formulation and in such amount as is therapeutically effective. The formulations are easily administered in a variety of dosage forms, such as the type of injectable solutions described above, but drug release capsules and the like can also be employed. For parenteral administration in an aqueous solution, for example, the solution should be suitably buffered if necessary and the liquid diluent first rendered isotonic with sufficient saline or glucose. These particular aqueous solutions are especially suitable for intravenous, intramuscular, subcutaneous and intraperitoneal administration. In this connection, sterile aqueous media which can be employed will be known to those of skill in the art in light of the present disclosure. For example, one dosage could be dissolved in 1 ml of isotonic NaCl solution and either added to 1000 ml of hypodermoclysis fluid or inj ected at the proposed site of infusion. Some variation in dosage will necessarily occur depending on the condition of the subject being treated. The person responsible for administration will, in any event, determine the appropriate dose for the individual subject.

In a particular embodiment, the invention relates to a pharmaceutical composition comprising NButGT for use during extracorporeal circulation.

In a particular embodiment, the invention relates to a pharmaceutical composition comprising ThiametG for use during extracorporeal circulation.

In a particular embodiment, the invention relates to a pharmaceutical composition comprising glutamine or glucosamine for use during extracorporeal circulation.

A further object of the present invention relates to a method of screening a compound that increases O-GlcNAcylation levels comprising i) providing a test compound and ii) determining the ability of said test compound to increase O-GlcNAcylation levels.

Any biological assay well known in the art could be suitable for determining the ability of the test compound to increase O-GlcNAcylation levels. In some embodiments, the assay first comprises determining the ability of the test compound to bind to a protein O-GlcNAcylation. In some embodiments, a population of cells is then contacted and activated so as to determine the ability of the test compound to increase O-GlcNAcylation. In particular, the effect triggered by the test compound is determined relative to that of a population of immune cells incubated in parallel in the absence of the test compound or in the presence of a control agent either of which is analogous to a negative control condition. The term "control substance", "control agent", or "control compound" as used herein refers a molecule that is inert or has no activity relating to an ability to modulate a biological activity or expression. It is to be understood that test compounds capable of increasing O-GlcNAcylation levels, as determined using in vitro methods described herein, are likely to exhibit similar modulatory capacity in applications in vivo. Typically, the test compound is small organic molecules. For example, the test compound according to the invention may be selected from a library of compounds previously synthesised, or a library of compounds for which the structure is determined in a database, or from a library of compounds that have been synthesised de novo. In some embodiments, the test compound may be selected form small organic molecules.

The invention will be further illustrated by the following figures and examples. However, these examples and figures should not be interpreted in any way as limiting the scope of the present invention.

FIGURES:

Figure 1: NButGT treatment increases cardiac O-GlcNAc levels. Evaluation by western blot of the O-GlcNAcylation levels of cardiac proteins in Sham, ECC and NButGT rats 5 hours after extubating. Sham: Sham procedure consisted of the whole protocol without priming the pump of ECC; ECC: The animals are cannulated and undergo an extracorporeal circulation procedure. Sham: Sham procedure consisted of the whole protocol without priming the pump of ECC; NButGT: The animals are cannulated and undergo an extracorporeal circulation procedure and received intravenous NButGT injections (lOmg/kg) to increase O- GlcNAc levels. Quantification of O-GlcNAcylation levels is normalized to stain free. Results are expressed as box and whisker. Statistical significance was assessed by Kruskal-Wallis test with uncorrected Dunn’s post-test (**: p<0.01).

Figure 2: Impact of ECC and NButGt on OGA and OGT cardiac expression. Evaluation by western blot of the cardiac expression of OGA (A) and OGT (B) in Sham, ECC and NButGT rats 5 hours after extubating. Sham: Sham procedure consisted of the whole protocol without priming the pump of ECC. ECC: The animals are cannulated and undergo an extracorporeal circulation procedure. NButGT: The animals are cannulated and undergo an extracorporeal circulation procedure and received intravenous NButGT injections (lOmg/kg) to increase O-GlcNAc levels. Quantification of O-GlcNAcylation levels is normalized to stain free. Results are expressed as box and whisker. Statistical significance was assessed by Kruskal- Wallis test with uncorrected Dunn’s post-test (**: p<0.01) n= 4 to 11. Figure 3: NButGT treatments limits the organ dysfunction. Mean arterial pressure throughout ECC and 5 hours after extubating in Sham, ECC and NButGT rats (A). Evaluation of lactates levels (B), creatininemia (C) and blood urea nitrogen levels (D) in Sham, ECC and NButGT rats 5 hours after extubating. Arterial bicarbonates levels at the start, the end of ECC and 5 hours after extubating in Sham, ECC and NButGT rats (E). ECC: The animals are cannulated and undergo an extracorporeal circulation procedure. Sham: Sham procedure consisted of the whole protocol without priming the pump of ECC; NButGT: The animals are cannulated and undergo an extracorporeal circulation procedure and received intravenous NButGT injections (lOmg/kg) to increase O-GlcNAc levels. Results are expressed as box and whisker. Statistical significance was assessed by 2-Way ANOVA with Bonferroni post hoc test. *: p < 0.05 ECC vs Sham; $: p < 0.05 NButGT vs Sham; #: p < 0.05 NButGT vs ECC

EXAMPLE:

Material & Methods

For the ECC group, animals were anaesthetized with 5% isoflurane/FiO2 1.0 in an induction box and maintained with a mask with 2% isoflurane. A rectal probe and a heating surgery platform (Harvard Apparatus, Molliston, MA) were used to control and maintain rats’ temperature at 37.5 ± 1°C during surgery and 36.5 ± 1°C during ECC. A bolus of fentanyl (12 pg.kg-1; Fentadon, Dechra, France), allowing pain relief during procedures, was slowly administered to avoid any respiratory failure. Prior to surgery, orotracheal intubation (14G cannula; Instech laboratories, USA) allowed anesthesia maintenance with 1.5% isoflurane/FiO2 1.0. Rats were curarized with an iv injection of Rocuronium bromide (Esmeron, Img/kg; Hospira, France) and mechanical ventilation was set (Harvard model 683, Harvard-apparatus, USA) with a tidal volume of 6 mL/kg and a respiratory rate of 58 ± 2 cycles/min. Three cannulas, filled with heparinized Ringer Lactate (30 UI.mL' ¹ ) were respectively inserted in the left femoral artery (PE- 10; Instech laboratories, USA) to monitor arterial blood pressure, in the right jugular vein (6Fr, Vygon, France) and in the left carotid (PE-50; Instech-laboratories, Plymouth, USA). Unfractionated heparin (300 Ul/kg; Panpharma, France) was injected in the jugular vein before ECC. ECC was initiated and pump speed was adjusted to reach the mean arterial pressure (MAP) minimum target of 60 mmHg. ECC have been facilitated with Phenylephrine infusion (Renaudin, France). An infusion of propofol (30 mg. kg' ¹ . hr' ¹ ; PropoVet, Abott, France) combined with fentanyl (2 pg. kg' ¹ . hr' ¹ ) replaced isoflurane Anesthesia during ECC. The venous route was clamped and the blood contained in the circuit was restituted before stopping the pump. Catheters were removed and vessels were tied with 5/0 silk threads (B. Braun, France) and wounds have been stitched (5/0 non-resorbable Vycril). Rats were finally weaned from anesthesia and extubated at the onset of signs of resumption of spontaneous respiratory activity. Rats received subcutaneous fluid therapy (10 mL.kg' ¹ , NaCl 0.9%, B. Braun, France) mixed with buprenorphine (0.03 mg. kg' ¹ , Buprecare®, Axience, France) and placed in a heating chamber. Five hours after extubating (H+5), hemodynamic was monitored under isoflurane anesthesia (1.5%, FiO2 1.0). Sham procedure consisted of the whole protocol without priming the pump of ECC. For the NButGT group, animals received intravenous NButGT injections (lOmg/kg) prior the surgery (at the same time that the bolus of fentanyl) and at the weaning from anesthesia.

Results

The ECC procedure does not impact the cardiac protein O-GlcNAcylation levels (Figure 1). We observe that the NButGT treatment, an OGA inhibitor, increases the O-GlcNAcylation levels of cardiac proteins (p<0.05) (Figure 1). We also observed that NButGT treatment increases also the myocardial OGA expression (Sham l±0.08; ECC 1 ,04±0.16; ECC + NButGT 6.8±2.9; p<0.01; n=4 to 11) (Figure 2A). On contrary, there was no evidence of variation in OGT expression across the protocol (Sham 1 ± 0.08; CEC 0.9 ± 0.04; CEC + NButGT 0.9 ± 0.09; p > 0.05; n=4 to 11) (Figure 2B). Mean arterial pressure decreases 5 hours after ECC procedure compared to the sham group (sham: 95.7 ± 3.7; ECC: 69.8 ± 7.7; mmHg; p<0.05) (Figure 3 A). The NButGT treatment tends to increase the mean arterial pressure compared to the ECC group (NButGT: 90.8 ± 10.3; mmHg; p = 0.11) (Figure 3 A). ECC procedure is associated with an organism injury with an increase in lactates, creatinine, blood urea nitrogen and bicarbonates levels 5 hours after ECC procedure (p<0.05) (Figure 3B-3E). NButGT treatment tends to reduce lactates and creatinine levels and decreases blood urea nitrogen and arterial bicarbonates 5 hours after ECC procedure (p<0.05) (Figure 3B-3E).

REFERENCES:

Reynolds MM, Annich GM. The artificial endothelium. Organogenesis. 2011 Jan- Mar;7(l):42-9. doi: 10.4161/org.7.1.14029.

Al-Fares AA, Randhawa VK, Englesakis M, McDonald MA, Nagpal AD, Estep JD, Soltesz EG, Fan E. Optimal Strategy and Timing of Left Ventricular Venting During Veno- Arterial Extracorporeal Life Support for Adults in Cardiogenic Shock: A Systematic Review and Meta- Analysis. Circ Heart Fail. 2019 Nov; 12(1 l):e006486. Casey LC. Role of cytokines in the pathogenesis of cardiopulmonary-induced multisystem organ failure. Ann Thorac Surg. 1993 Nov;56(5 Suppl):S92-6.

Esper SA, Subramaniam K, Tanaka KA. Pathophysiology of Cardiopulmonary Bypass: Current Strategies for the Prevention and Treatment of Anemia, Coagulopathy, and Organ Dysfunction. Semin Cardiothorac Vase Anesth. 2014 Jun;18(2): 161-76.

Kats S, Schonberger JP, Brands R, Seinen W, van Oeveren W. Endotoxin release in cardiac surgery with cardiopulmonary bypass: pathophysiology and possible therapeutic strategies. An update. Eur J Cardiothorac Surg. 2011 Apr;39(4):451-8.

Chavez-Tostado M, Carrillo-Llamas F, Martinez-Gutierrez PE, Alvarado-Ramirez A, Lopez-Taylor JG, Vasquez- Jimenez JC, Fuentes-Orozco C, Rendon-Felix J, Irusteta-Jimenez L, Calil-Romero VC, Ramirez-Jimenez JA, Michel-Espinoza LR, Contreras-Lopez CK, Cuesta-Marquez LA, Gonzalez-Ojeda A. Oral glutamine reduces myocardial damage after coronary revascularization under cardiopulmonary bypass. A randomized clinical trial. Nutr Hosp. 2017 Mar 30;34(2):277-283.

Lomivorotov VV, Efremov SM, Shmirev VA, Ponomarev DN, Lomivorotov VN, Karaskov AM. Glutamine is cardioprotective in patients with ischemic heart disease following cardiopulmonary bypass. Heart Surg Forum. 2011 Dec;14(6):E384-8.

Ledee DR, Kajimoto M, O'Kelly Priddy CM, Olson AK, Isern N, Robillard-Frayne I, Des Rosiers C, Portman MA. Pyruvate modifies metabolic flux and nutrient sensing during extracorporeal membrane oxygenation in an immature swine model. Am J Physiol Heart Circ Physiol. 2015 Jul l;309(l):H137-46.