Effect of dietary polyunsaturated fatty acids on rat tissue oxylipin profiles
There is much information on the effects of dietary lipids on tissue fatty acid composition, but little data on their bioactive lipid metabolites that mediate their effects on health and disease. Therefore diets differing in levels of linoleic (LA), α-linolenic (ALA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were provided to male and female weanling rats for 6 weeks, and fatty acids and their oxygenated metabolites (oxylipins) were quantified in kidney, liver and serum. The findings reveal that although oxylipin profiles are generally similar to fatty acid profiles there are some notable exceptions: dietary LA can increase LA and arachidonic acid derived oxylipins without changing the precursor fatty acid level; dietary ALA can increase DHA oxylipins without changing DHA levels. Male tissues generally had higher levels of oxylipins than females, with a few exceptions (e.g. F-series prostaglandins). These findings have implications for dietary recommendations for LA and n-3 fatty acids.