Karyn Esser, PhD

My lab has pioneered research on the role of circadian rhythms and the circadian clock mechanism in skeletal muscle homeostasis and systemic health. We have defined that the muscle clock is necessary for maintenance of muscle function (i.e. strength) and metabolic flexibility with a key role regulating glucose metabolism. Our current research directions include questions about the role of the muscle clock in aging and chronic diseases and the potential for targeting the muscle clock through chronotherapeutic approaches to improve muscle and system health. Our therapeutic approaches include use of scheduled exercise to enhance muscle clock function with aging, use of AAV approaches to boost clock function in models of chronic disease.

The lab also has a significant interest in the mechanisms through which exercise regulates the muscle clock and contributes to systemic health through our role within the MoTrPAC consortium. Our clock work has shown that the phase settings of the muscle clock are uniquely sensitive to the time of muscle contractions/exercise and occur in the absence of changes in the central clock. Our studies within MoTrPAC are defining the molecular pathways involved in acute and chronic exercise training across 17 tissues, 2 ages and both sexes. These multi-omic maps provide foundational new data and are helping to identify the system-wide transducers of health.

We are also active within the Studies of Muscle, Mobility and Aging (SOMMA) multi-site human aging clinical study. We contribute molecular analyses and are asking questions about circadian behavior and gene expression changes with age and their association with mobility and health.

There are a number of research projects ongoing in the lab. 1. Studies focused on the fundamental role of the circadian clock mechanism in muscle for healthy aging and in diseases including muscular dystrophy, cancer cachexia and others. 2. Studies on the mechanisms through which the clock mechanism in muscle, and other tissues, is a necessary component for healthy exercise adaptations. 3. The SOMMA aging study: use different -omics platforms to define molecular and metabolic changes in muscle in human aging. One goal is to identify molecular signatures that track with functional decline to enhance our understanding and potentially provide new therapeutic targets.