Project Summary Type 2 diabetes (T2D) is a leading cause of death nationwide with 65% of mortality due to cardiovascular disease. The term “diabetic cardiomyopathy (T2DCM)” refers to a condition with adverse myocardial structural changes, in the absence of hypertension and vascular pathology. Although T2D and CVD are tightly intertwined, we lack a deeper understanding of T2DCM at the molecular and cellular levels. In recent years, sodium-glucose cotransporter-2 (SGLT2) inhibitors have emerged as a promising therapeutic for T2DCM, but the precise protective mechanisms in cardiomyocytes, fibroblasts, and endothelial cells which construct the cardiac microenvironment remain incompletely understood. In this multi-PI R01 renewal, our team will elucidate the mechanisms of metabolic interplay within and between cardiovascular cells which confer cardiac protection by SGLT2 inhibition. We will harness induced pluripotent stem cell (iPSC) technology to generate diabetic models of cardiovascular cell types for cellular and metabolic phenotyping of SGLT2 inhibition in vitro (Aim 1). We will construct iPSC-derived engineered heart tissues for functional phenotyping and proteomic determination of the SGLT2 inhibitor protein interactome (Aim 2). Afterward, we will validate cardioprotective mechanisms in a diabetic mouse model at single-cell resolution (Aim 3). In summary, understanding the exact role and mechanism of SGLT2 inhibition in T2DCM may contribute to finding new therapeutic modalities for the treatment of metabolic heart diseases.