MODULATION OF CYTOKINE PRODUCTION BY DEHYDROEPIANDROSTERONE (DHEA) PLUS MELATONIN (MLT) SUPPLEMENTATION OF OLD MICE

Tissue levels of the antioxidants melatonin (MLT) and dehydroepiandros terone (DHEA) decline with age, and this decline is correlated with im mune dysfunction. The aim of the current study is to determine whether hormone supplementation with MLT and DHEA together would synergize to reverse immune senescence. Old (16.5 months) female C57BL/6 mice were treated with DHEA, MLT, or DHEA + MLT. As expected, splenocytes were significantly (P < 0.05) higher in old mice as compared to young mice. DHEA, MLT, and DHEA + MLT significantly (P < 0.005) increased B cell proliferation in young mice. However, only MLT and DHEA + MLT signific antly (P < 0.05) increased B cell proliferation in old mice. DHEA, MLT , and DHEA + MLT help to regulate immune function in aged female C57BL /6 mice by significantly (P < 0.05) increasing Th1 cytokines, IL-2, an d IFN-gamma or significantly (P < 0.05) decreasing Th2 cytokines, IL-6 , and IL-10, thus regulating cytokine production. DHEA and MLT effecti vely modulate suppressed Thf cytokine and elevated Th2 cytokine produc tion; however, their combined use produced only a limited additive eff ect.