Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production.
Effects of a dietary intake of the polyunsaturated omega-6 essential fatty acids (EFAs) linoleic and gamma-linolenic acids (GLA) on blood lipids, platelet function, and vascular prostacyclin production were studied 12 hyperlipidemic patients (doses of 3 g/day) and 12 male Wistar rats (doses of 3 mg/kg/day) for 4 months. In humans, GLA supplementation decreased plasma triglyceride (TG) levels by 48% (p < 0.001) and increased HDL-cholesterol concentration by 22% (p < 0.01). Total cholesterol and LDL-cholesterol levels were significantly decreased by omega-6 EFAs. Platelet aggregation induced by low concentrations of adenosine diphosphate (ADP) and epinephrine, and serum thromboxane B2 decreased by 45% both in humans and animals after GLA supplementation. Bleeding time increased 40% (p , 0.01). In rats, vascular prostacyclin production measured by radioimmunoassay of 6-keto-PGF1 alpha was enhanced by GLA intake. These effects of omega-6 EFAs may contribute to cardiovascular protection and prevention of the atherosclerotic disease.
Department of Medicine, School of Medicine, University of Chile, Santiago.
M
M
Guivernau
N
N
Meza
P
P
Barja
O
O
Roman
D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001161:Arteriosclerosis / Q000517:prevention & control; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage / Q000494:pharmacology*; D004837:Epinephrine / Q000494:pharmacology; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013929:Thromboxane B2 / Q000097:blood; D014280:Triglycerides / Q000097:blood; D017965:gamma-Linolenic Acid / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004042:Dietary Fats, Unsaturated; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D010975:Platelet Aggregation Inhibitors; D014280:Triglycerides; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D000244:Adenosine Diphosphate; D017965:gamma-Linolenic Acid; D002784:Cholesterol; D004837:Epinephrine