Calen P. Ryan, M. Geoffrey Hayes, Nanette R. Lee, Thomas W. McDade, Meaghan J. Jones, Michael S. Kobor, Christopher W. Kuzawa, Dan T. A. Eisenberg
Evolutionary theory predicts that reproduction entails costs that detract from somatic maintenance, accelerating biological aging. Despite support from studies in human and non-human animals, mechanisms linking ‘costs of reproduction’ (CoR) to aging are poorly understood. Human pregnancy is characterized by major alterations in metabolic regulation, oxidative stress, and immune cell proliferation. We hypothesized that these adaptations could accelerate blood-derived cellular aging. To test this hypothesis, we examined gravidity in relation to telomere length (TL, n = 821) and DNA-methylation age (DNAmAge, n = 397) in a cohort of young (20–22 year-old) Filipino women. Age-corrected TL and accelerated DNAmAge both predict age-related morbidity and mortality, and provide markers of mitotic and non-mitotic cellular aging, respectively. Consistent with theoretical predictions, TL decreased (p = 0.031) and DNAmAge increased (p = 0.007) with gravidity, a relationship that was not contingent upon resource availability. Neither biomarker was associated with subsequent fertility (both p > 0.3), broadly consistent with a causal effect of gravidity on cellular aging. Our findings provide evidence that reproduction in women carries costs in the form of accelerated aging through two independent cellular pathways. © 2018, The Author(s).
Department of Anthropology, Northwestern University, Evanston, 60208, IL, United States; Division of Endocrinology, Metabolism and Molecular Medicine, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, 60611, IL, United States; Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, 60611, IL, United States; Office of Population Studies Foundation Inc., Cebu City, Philippines; Department of Anthropology, Sociology, and History, University of San Carlos, Cebu City, Philippines; Institute for Policy Research, Northwestern University, Evanston, 60208, IL, United States; Child and Brain Development Program, Canadian Institute for Advanced Research, Toronto, M5G 1Z8, ON, Canada; BC Children’s Hospital Research Institute, University of British Columbia, Vancouver, V5Z 4H4, BC, Canada; Department of Anthropology, University of Washington, Seattle, 98195, WA, United States; Center for Studies in Demography and Ecology, University of Washington, Seattle, 98195, WA, United States
