Dietary restriction in Rhesus monkeys: Lymphopenia and reduced mitogen-induced proliferation in peripheral blood mononuclear cells

Dietary restriction (DR) markedly extends mean and maximal life span, and retards the rate of biological aging in rodent models; however it is unknown if these results occur in primate species. The purpose of the current study was to investigate selected immunologic outcomes in Rhesus monkeys subjected to DR for a period of seven years. Similar to observations in mice on DR, lymphopenia occurred in the restricted monkeys. Compared to normally fed controls, the mitogen-induced proliferative responses of peripheral blood mononuclear cells (PBMC) were reduced in monkeys subjected to DR very early in life (up to 1 year), but not in others restricted in young adulthood (3-5 years). These data indicate that lymphopenia is a shared occurrence in rodents and primates on DR. However, the mitogen-induced proliferative data accumulated in rodents and primates cannot now be compared because PBMC have not been studied long enough or in comparable detail in primates fed restricted diets. (C) 1997, Editrice Kurtis.