Mallory Jordan Peters

Over the course of our evolution, our skeletal system has become entangled with our immune and endocrine systems due to their shared cellular origins. This has resulted in bone cells being controlled by the same signaling pathways and hormones that control our immune and inflammatory response systems. Cortisol, the “stress” hormone, is a steroid that controls many cellular processes throughout the body, including the effects of the fight-or-flight response we experience during times of immediate stress. My central objective is to test predictions of Life History Theory and Mismatch Theory on the interactions between stress and bone metabolism. My hypotheses predict that cortisol will have a suppressive effect on cells responsible for depositing new bone and on the cells responsible for resorbing old bone. The fight-or-flight response could cause serious interruptions to normal skeletal metabolism, increasing the risk of future injury through fractures. Despite this risk, the relationship between cortisol and skeletal metabolism is likely tightly regulated through Antagonistic Pleiotropy; the theory that genes linked to traits that are beneficial early in life are maintained despite risks to health or safety later in life. To evaluate these possible trade-offs, this research will determine how cortisol interrupts skeletal metabolism.