Is your blood sugar undermining your workouts? Hyperglycemia impairs exercise responses and adaptations in muscle
Abstract: Chronic high blood glucose (known as hyperglycemia) is associated with an impaired adaptive response to aerobic exercise, which includes reduced improvements in aerobic fitness. Low aerobic fitness (also known as low VO2peak) is the single greatest predictor of mortality; it is critical that we establish and understand the causal factors that contribute to this phenotype. We demonstrated– in western diet (WD) feeding and streptozotocin (STZ) models of hyperglycemia in mice, and humans with hyperglycemia– that chronic high glucose directly regulates several molecular mechanisms that underpin low fitness. To test whether glucose lowering therapy can restore the response to exercise, we treated hyperglycemic mice with an SGLT2 inhibitor, Canagliflozin (Cana). Exercise responses and adaptations were normalized, and muscle-specific adaptive remodeling was restored when hyperglycemia was reduced using SGLT2i. Conclusions: These data demonstrate, for the first time, that hyperglycemia directly impairs whole-body and muscles-specific responses and adaptations. Future Directions: As rates of metabolic disease skyrocket globally, the incidence of hyperglycemia is growing rapidly, which may lead to a population that is increasingly resistant to improving VO2peak with training. We are now investigating other unidentified skeletal muscle systems that are (dys)regulated by hyperglycemia.
Bio: Tara is a Banting and Best Insulin Discovery Assistant Professor at the University of Toronto, in the Department of Physiology. She completed her graduate training at the University of Guelph, with Drs. David Dyck and David Wright, where she focused on identifying how cytokines and hormones regulate key metabolic pathways in endocrine tissues during exercise. In 2016, she moved to Joslin Diabetes Center/Harvard Medical School for her first postdoc and studied the intersection of hyperglycemia and exercise in mice and humans. In 2021, she began applying her everlasting interest in stress biology towards studying pancreatic ꞵ cell stress and metabolism during the progression to diabetes. Her group will focus on decoding the many putative and unknown links between hyperglycemia, cell stress and diabetes (T1D and T2D) in important endocrine tissues, including pancreatic ꞵ cells and skeletal muscle.
Location: Life Sciences Building, Room 1002
This seminar will be in hybrid format. Please reach out to kin.communications@ubc.ca for the Zoom details.