Rafaela SC Takeshita

RAFAELA TAKESHITA, Kent State University, Kent, Ohio, was awarded funding in April 2021 to aid research on “Uncovering Adrenarche: Neuroendocrine Basis of Human Longevity.” The adrenal androgen dehydroepiandrosterone-sulfate (DHEAS) is the highest circulating hormone in humans and has been implicated in brain development and in longevity. In macaques as baboons, DHEAS levels are the highest at birth and decline continuously with advancing age, but in humans and in great apes, the levels of this hormone begin to increase prior to puberty and continue rising to mid-adulthood. This post-natal increase in adrenal androgen is called adrenarche and has been hypothesized to enhance brain development and to promote longevity, which is pivotal for understanding human origins. This project aimed to: 1) examine age-related changes in DHEAS levels in several primate genera to determine the origins of adrenarche; and 2) to test whether DHEAS is correlated with cognitive function in nonhuman primates, using chimpanzee as a model. We found evidence of a postnatal increase in DHEAS levels in some neotropical primates and in lesser apes, suggesting that adrenarche is not unique to great apes as previously thought. We also found that DHEAS, when controlled for stress, is positively correlated with cognitive function in chimpanzees. These findings support our hypothesis that adrenarche may have been a key mechanism that promoted K-selected traits in human evolution.