To provide a method for treating a patient in need of therapy for a neurodegenerative disease.

The method includes administering a therapeutically effective dose of a triglyceride oil containing both γ-linolenic acid and linoleic acid residues as triglyceride ester, wherein the ratio of γ-linolenic acid to linoleic acid residues at the sn-2 position of the triglyceride is at least 0.8; the amount of γ -linolenic acid residues at the sn-2 position is at least 18%, wherein the oil is administered at a dose sufficient to maintain or elevate TGF-β1 levels in the patient at a therapeutic level. Preferred oils are Borage or Mucor oils having at least 35% of the sn-2 position fatty acid residues as γ-linolenic acid.