PROJECT SUMMARY Cardiovascular disease (CVD) kills one person every 37 seconds in the U.S. and those with type 2 diabetes mellitus (T2DM) have a 2-fold higher mortality following a myocardial infarction. The principal cause of T2DM morbidity and mortality is CVD. Genetic risk factors and biomarkers for T2DM have been identified but neither accurately predicts cardiovascular complications. An emerging, novel early prediction method of CVD in T2DM is epigenetics. Epigenetic changes are modifications to the genome that regulate gene transcription without actually changing the underlying nucleotide sequence. Endothelial cells (ECs), which line the interior of blood vessels, become dysfunctional in T2DM and are the first step in CVD progression. ECs maintain long-term expression of pro-inflammatory genes even after normal glucose levels have been attained, suggesting epigenetic changes might be responsible for enduring changes in gene expression that contribute to CVD. It is unknown, however, the extent to which epigenetic changes mediate early cardiac endothelial cell dysfunction in T2DM and whether these changes can be rescued with lifestyle interventions like exercise. The short-term goal of this project is to determine the effect of hyperglycemia on epigenetic modifications (measured via chromatin accessibility) in cardiac endothelial cells and how these are modified by an exercise intervention in a translational mouse model. The long-term goal is to help develop early effective prediction, prevention, and management of cardiovascular complications in patients with T2DM. I hypothesize hyperglycemia will cause differential chromatin accessibility in inflammatory pathway genes that will be prevented by concurrent aerobic exercise. I will test this hypothesis using two specific aims: 1. Determine the effect of hyperglycemia and insulin resistance on epigenetic changes in cardiac endothelial cells. I will use a translational mouse model, which is readily available in our lab, to implement a diet intervention and isolate cardiac endothelial cells. 2. Test whether an aerobic exercise intervention prevents hyperglycemia-induced epigenetic changes in cardiac endothelial cells. I will test four randomly assigned groups of mice: control diet (CD), CD + exercise, high fat diet (HFD), HFD + exercise. This project is significant and innovative because it investigates a long- standing cause of death in an extremely prevalent disease using a novel epigenetic analysis approach. This project fits within the applicant’s long-term research goals of using translational science models to improve understanding, prevention, and treatment of cardiovascular complications in patients with chronic metabolic diseases. This research will establish the early effects of hyperglycemia and insulin resistance on epigenetic changes in cardiac endothelial cells and whether they can be mitigated through exercise, setting the groundwork for effective early identification and treatment...