Divergent effects of human lymphokine derived oligopeptides on PMNLs function of young and aged healthy subjects.
The effects of low molecular weight lymphokine-derived oligopeptides (LK-OPs) on PMNLs effector functions and receptor mediated biochemical events were studied in the case of healthy young and aged subjects. In the case of young subjects the low mol. wt. LK-OPs stimulated the Fc gamma receptor-mediated effector functions of PMNLs, whereas an inhibition was observed in PMNLs of the elderly (extracellular cytotoxicity and intracellular killing). The underlying biochemical events, induced by low mol. wt. LK-OPs stimulation, were also investigated. In PMNLs of young subjects the oxidative metabolism was stimulated (enhanced O2 consumption, O2 and H2O2 production) by low mol. wt. LK-OPs, while in elderly subjects it was inhibited. The cyclic nucleotides regulating the Fc gamma receptor mediated effector functions and the oxygen radicals formation showed an altered dynamic response under low mol. wt. LK-OPs stimulation with aging i.e. the cGMP level could not be changed at all. Our results suggest that low mol. wt. LK-OPs induced inhibition of Fc gamma receptor mediated effector functions with aging could be partly explained by an altered post receptorial coupling switch and as a consequence the lymphokines could not play their role of immunomodulators further impairing the altered immune response with aging.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D066298:In Vitro Techniques; D008222:Lymphokines / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects*; D009842:Oligopeptides / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D013481:Superoxides / Q000378:metabolism
D008222:Lymphokines; D009842:Oligopeptides; D013481:Superoxides; D006861:Hydrogen Peroxide; D000242:Cyclic AMP; D005979:Glutathione Peroxidase; D006152:Cyclic GMP