Effects of feeding lipids of different fatty acid compositions upon rat lymphocyte proliferation

Weanling Wistar rats were fed for 8 weeks on a low fat (3% by weight) diet (LF) or on diets containing 15% by weight hydrogenated coconut oil (coconut oil), cocoa butter, cashew kernel oil (cashew oil), canola oil or soya bean oil (soya oil). Each of the high fat diets resulted in inhibition of spleen lymphocyte proliferation in response to concanavalin A (Con A), a T-cell mitogen. Feeding the soya oil diet caused more than 95% inhibition of proliferation, compared with feeding the LF diet. Amongst the high fat diets, feeding the cashew, canola or soya oil diets resulted in inhibition of proliferation compared with feeding the coconut oil diet while feeding the soya oil diet resulted in inhibition of proliferation compared with feeding the cocoa butter or canola oil diets. Proliferation of lymphocytes in response to Con A was also investigated using whole blood culture. Once again, feeding the soya oil diet resulted in a dramatic decrease in proliferation (80%) compared with feeding the LF diet. Feeding the soya oil diet also inhibited proliferation compared with feeding the coconut oil, cocoa butter or cashew oil diets. Feeding the canola oil diet resulted in inhibition of proliferation compared with feeding the LF or cocoa butter diets.