Effect of fatty acid-rich diets on thymocyte proliferation and thymus involution during growing.

The effect of poly-unsaturated and saturated fatty acid-rich diet on the proliferation response of T and B lymphocytes in vitro was investigated. Also, a mitotic index of thymocytes and of thymus epithelial reticular-like cells and thymic involution coefficient were examined in vivo. w-6 PUFA-rich diet enhanced the rate of T (eightfold) and B (fourfold) lymphocyte proliferation, whereas saturated fatty acids did not show an important effect. However, both fat-rich diets increased the mitotic index of thymocytes and thymus involution index in vivo. These findings suggest that fat-rich diets may accelerate thymus involution during growing, possibly aggravating the impairment of the immune function which usually occurs under this condition.