Effect of L-carnitine on proliferative response and mRNA expression of some of its associated factors in splenic mononuclear cells of male broiler chicks

摘要

The effect of L-carnitine supplementation on mitogen (concanavalin A, Con A) induced proliferation of mononuclear cells (MNC) in the spleen was investigated in broiler chickens at different ages. Day-old chickens were fed a diet supplemented with or without L-carnitine (100 ppm) for 24 days. The carnitine-supplemented group showed greater proliferation of MNC in the spleen in response to Con A than that of the control group at 24 days of age. In addition, at 24 days of age the carnitine-supplemented group showed higher expression of interleukin (IL)-2 and interferon (IFN)-d mRNA, but lower expression of inducible nitric oxide synthase (iNOS) in the Con A-stimulated splenic MNC than the control group. The enhancement effect of L-carnitine on MNC proliferation and IL-2 mRNA expression was not found in chicks at 14 days of age. Addition of L-carnitine (50 nmol/mL) to the culture medium enhanced proliferation and IL-2 mRNA expression of splenic MNC obtained from 24-day-old but not from 14-day-old broiler chickens. The results suggest that L-carnitine is capable of enhancing MNC proliferation in broiler chickens at 24 days of age partly through increasing IL-2 and IFN-d production and decreasing NO production.