Prevention of immune dysfunction and vitamin E loss by dehydroepiandrosterone and melatonin supplementation during murine retrovirus infection

Female C57BL/6 mice infected with the LP-BM5 leukaemia retrovirus developed murine acquired immune-deficiency syndrome (AIDS). Dehydroepiandrosterone (DHEA) and melatonin (MLT) modify immune dysfunction and prevent lipid pero xidation. We investigated whether DHEA and MLT could prevent immune dysfunc tion, excessive lipid peroxidation, and tissue vitamin E loss induced by re trovirus infection. Retrovirus infection inhibited the release of T helper 1 (Th1) cytokines, stimulated secretion of Th2 cytokines, increased hepatic lipid peroxidation, and induced vitamin E deficiency. Treatment with DHEA or MLT alone, as well as together, largely prevented the reduction of B- an d T-cell proliferation as well as of Th1 cytokine secretion caused by retro virus infection. Supplementation also suppressed the elevated production of Th2 cytokines stimulated by retrovirus infection. DHEA and MLT simultaneou sly reduced hepatic lipid peroxidation and prevented vitamin E loss. The us e of DHEA plus MLT was more effective in preventing retrovirus-induced immu ne dysfunction than either DHEA or MLT alone. These results suggest that su pplementation with DHEA and MLT may prevent cytokine dysregulation, lipid o xidation and tissue vitamin E loss induced by retrovirus infection. Similar ly, hormone supplementation also modified immune function and increased tis sue vitamin E levels in uninfected mice.