The effect of dietary polyenylphosphatidylcholine on microsomal delta-6-desaturase activity, fatty acid composition, and microviscosity in rat liver under oxidative stress

✍ Scribed by Pier L. Biagi; Alessandra Bordoni; Silvana Hrelia; Michele Celadon; Edoardo Turchetto

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 502 KB
• Volume: 4
• Category: Article
• ISSN: 0955-2863
• DOI: 10.1016/0955-2863(93)90108-9

✦ Synopsis

Polyenylphosphatidylcholine i.s a eholine-glycerop/tospholipid containing up to 80% of total Jatty acids as linoleic acid anti may be an important factor in ensuring normal functioning of cell membranes. We tested the effect of a polyenylphosphatidylcholine-supplemented diet and compared it with both a trilino&insupplemented and a laboratory chow diet on the fatty acid composition, microviscosity, and delta-6desaturase activity of liver microsomal membranes of 12-month-ohl rats, in the absence or presence of oxidative stress induced by adriamvein. Polvenylphosphatidylcholine-and trilinolein-supplemented diets showed a similar increase in linoleic acid content and delta-6-desaturase activity in liver microsomes, indicating that low amounts of linoleic acid are able to partially restore the enzyme activity in old rats, independent of the source o]'linoleic acid. After adriamycin treatment, delta-6-desaturase activity increased in polyenylphosphatidylcholine and trilinolein groups, indicating a protective mechanism against the damage induced by polyunsaturated Jatty acid peroxidation. The measurement of malondialdehyde production showed a protective e[fect on adriamycin-induced lipid peroxidation by polyenylphosphatidylcholme supplementation only. Microsomal membrane mieroviscosity did not change independent of diet and adriamytin treatment, suggesting that the response of microsomes to lipid peroxidation might be the maintenance of a given membrane order. Administration of polyenylphosphatidyh:holine can prevent or minimize the liver damage induced by adriamycin treatment.