Effect of Adiposity on Hepatic and Peripheral Insulin Resistance in Type 1 Diabetes

A major focus of this program of research will be directed at advancing the understanding of the metabolic consequences of obesity and puberty in adolescents with T1D. Thus, an innovative aspect of this research is that it will be the first to use these sophisticated metabolic techniques to examine the effects of obesity and hepatic steatosis on insulin sensitivity in pubertal adolescents with T1D; namely, the 2-step hyperinsulinemic euglycemic clamp with tracer enhancement, which will allow for definition of hepatic and peripheral insulin resistance, glycerol turnover, and glucose and fat oxidation. Further, a second novel aspect is that this will be the first study to utilize gold standard MRI methods to quantify and compare intrahepatic fat content in lean and obese adolescents with T1D. This will allow a global and more detailed understanding of the potential alterations of insulin's effects on key insulin sensitive tissues in youth that are impacted by both T1D and obesity. Furthermore, evaluation of biomarkers for insulin resistance and fatty liver disease in this population will be performed for the first time.