Age-related changes in the neuropeptide Y effects on murine lymphoproliferation and interleukin-2 production

Neuropeptide Y (NPY) modulates several aspects of the immune response but i t is not known whether NPY responsiveness is altered with aging. In this wo rk, the in vitro effect of NPY at concentrations ranging from 10(-14) M to 10(-7) M on lymphoproliferation has been studied in spleen, axillary node a nd thymus leukocytes from young, adult, mature and old BALB/c mice. The spo ntaneous proliferation of spleen lymphocytes from young mice was significan tly stimulated by NPY. In response to the mitogen Con A, lymphoproliferatio n and IL-2 release by lymphocytes were inhibited significantly by NPY, thes e effects disappearing with aging. The results show that NPY is a modulator of lymphoproliferation and that this effect disappears progressively with age. Moreover, this regulatory role of NPY may be carried out through a dec rease in IL-2 production. (C) 2000 Published by Elsevier Science Inc.