Polyunsaturated (n-3) Fatty Acids Susceptible to Peroxidation Are Increased in Plasma and Tissue Lipids of Rats Fed Docosahexaenoic Acid–Containing Oils

• Published in: The Journal of nutrition Vol. 130; no. 12; pp. 3028 - 3033
• Main Authors: Song, Jin Hyang, Fujimoto, Kenshiro, Miyazawa, Teruo
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.12.2000; American Society for Nutritional Sciences; American Institute of Nutrition
• Subjects: Animals; Arachidonic Acid - analysis; Biological and medical sciences; chemiluminescence; Chromatography, High Pressure Liquid; Docosahexaenoic Acids - administration & dosage; Docosahexaenoic Acids - pharmacology; Fatty acids; Fatty Acids, Omega-3 - blood; Fatty Acids, Omega-3 - physiology; Feeding. Feeding behavior; fish oil; Fish Oils - administration & dosage; Fish Oils - pharmacology; Fundamental and applied biological sciences. Psychology; Kidney - metabolism; Kidneys; Lipid Metabolism; lipid peroxidation; Lipid Peroxidation - drug effects; Lipids; Liver; Liver - metabolism; Luminescent Measurements; Male; Oils & fats; Oxidation; Oxidative Stress; phospholipid hydroperoxide; Phospholipids - analysis; Plasma; Rats; Rats, Sprague-Dawley; Rodents; Thiobarbituric Acid Reactive Substances - analysis; Triglycerides - analysis; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitamin E - analysis; α-tocopherol; EE; phospholipid hydroperoxide; PUFA; chemiluminescence; fish oil; PLOOH; CL; TBARS; MDA; lipid peroxidation; FAME; PCOOH; TG; PEOOH; α-TOC; PI; rats; DHA; PL; α-tocopherol; Rat; Rodentia; Lipids; Supplemented diet; Docosahexaenoic acid; Feeding; Blood plasma; Tissue; Vertebrata; Mammalia; Animal; Plasma membrane; Macronutrient; Peroxidation
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/130.12.3028

Docosahexaenoic acid [DHA, 22:6(n-3)], a major component of membrane phospholipids in brain and retina, is profoundly susceptible to oxidative stress in vitro. The extent of this peroxidation in organs when DHA is ingested in mammals, however, is not well elucidated. We investigated the effect of dietary DHA-containing oils (DHA 7.0–7.1 mol/100 mol total fatty acids), in the form of triacylglycerols (TG), ethyl esters (EE) and phospholipids (PL), on tissue lipid metabolism and lipid peroxidation in rats. Groups of Sprague-Dawley rats were fed semipurified diets containing 15 g/100 g test oils and were compared with those fed 80% palm oil and 20% soybean oil as the control (unsupplemented group) for 3 wk. The DHA oil diets markedly increased (P < 0.05) the levels of DHA in the plasma, liver and kidney, 1.5–1.9, 2.5–3.8 and 2.2–2.5 times the control values, respectively, whereas there was a concomitant reduction (P < 0.05) in arachidonic acid. All forms of DHA oil caused lower TG concentrations in plasma (P < 0.05) and liver (P < 0.05), but had no effect in kidney. The DHA oil–fed rats had greater phospholipid hydroperoxide accumulations in plasma (191–192% of control rats), liver (170–230%) and kidney (250–340%), whereas the α-tocopherol level was reduced concomitantly (21–73% of control rats). Consistent with these results, rats fed DHA-containing oils had more thiobarbituric reactive substances in these organs than the controls. Thus, high incorporation of (n-3) fatty acids (mainly DHA) into plasma and tissue lipids due to DHA-containing oil ingestion may undesirably affect tissues by enhancing susceptibility of membranes to lipid peroxidation and by disrupting the antioxidant system. J. Nutr. 130: 3028–3033, 2000.