Modulation of prostaglandin synthesis in rat peritoneal macrophages with omega-3 fatty acids.
In view of the findings that omega 3 fatty acids inhibit the synthesis of prostaglandins (PG) from arachidonic acid (20:4 omega 6) and that among immunologically active cells, the macrophage is a major producer of PG, we undertook a study of the effect of dietary alpha-linolenic acid (18:3 omega 3) on PG synthesis in the macrophage. Rats were fed purified diets containing either 10% corn oil (CO) or linseed oil (LO), providing either a low (1/32) or high (3.5/1) ratio of 18:3 omega 3 to 18:2 omega 6, respectively, for 6 weeks. Fatty acid analysis of macrophage phospholipids showed that there was an appreciable increase in the percentage of omega 3 fatty acids and a decrease in the omega 6 fatty acids in macrophages from rats fed the LO diet. The changes in fatty acid composition were associated with a significant decrease in the synthesis of prostaglandin E (PGE) by macrophages from rats fed the LO diet. Macrophages from rats fed the 2 dietary oils did not differ in their ability to degrade PG, thus the difference in PG production appeared to be a consequence of decreased synthesis only. The dietarily induced changes in PGE synthesis were readily overcome in vitro by culturing macrophages with complexes of fat-free bovine serum albumin and either 20:4 omega 6 or 20:5 omega 3.
D000818:Animals; D001202:Ascitic Fluid; D003314:Corn Oil; D004041:Dietary Fats / Q000008:administration & dosage*; D005227:Fatty Acids / Q000378:metabolism; D008042:Linolenic Acids / Q000494:pharmacology*; D008043:Linseed Oil / Q000008:administration & dosage; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D009821:Oils / Q000008:administration & dosage; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism; D011458:Prostaglandins E / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains; D013329:Structure-Activity Relationship; D017962:alpha-Linolenic Acid
D004041:Dietary Fats; D005227:Fatty Acids; D008042:Linolenic Acids; D009821:Oils; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D011458:Prostaglandins E; D017962:alpha-Linolenic Acid; D008043:Linseed Oil; D003314:Corn Oil