UC Berkeley

Mammalian physiology is exquisitely tuned to anticipate and synchronize with environmental oscillations. These oscillations appear to occur in a networked fashion across systems and timescales, such that information about difficult-to-measure systems (e.g., reproductive) may be garnered from easy-to-measure systems (e.g., autonomic, and thermoregulatory). These network dynamics and their implications for health require deep exploration. The goals of this dissertation are to 1) investigate the relationship among reproductive, metabolic, and autonomic rhythms at the hourly to ovulatory timescales, and 2) investigate the conditions under which peripheral timeseries features may serve as proxies for hormonal status. This dissertation traverses discrete stages of reproductive life: adolescence, adulthood, and menopause; as well as the impacts of exogenous network perturbations at each stage of life. Chapter 1 reviews central mechanisms of coupled oscillations in the reproductive and thermoregulatory systems. Chapters 2 and 3 investigate the development of thermoregulatory rhythms across adolescence, their dependence on endogenous and exogenous reproductive hormones, their interaction with natural and artificial environments, and derive peripheral features to monitor reproductive development in the rat. Chapter 4 extends these findings to adult women and investigates shared rhythmicity among autonomic and thermoregulatory outputs and sex hormones for the purposes of LH surge prediction or identification of its absence in menopause. With an eye toward future developments in sex hormone replacement, Chapter 5 compares the effects of the most advanced forms of continuous hormone replacement therapy on biological rhythms in metabolic output. These studies inform our understanding of the structure of reproductive, metabolic, and autonomic networks across life, and reveal translational tools for reproductive health.