PC and type 2 diabetes mellitus: In one example, Lee et al. used HP 13C MRI to determine changes in mitochondrial metabolism in a mouse model of high-fat diet induced type 2 diabetes by measuring real-time hepatic gluconeogenesis in the animals.70 The authors discovered that increased metabolism of HP [1-13C]pyruvate through pyruvate carboxylase (PC), as confirmed by increased signals of four-carbon metabolites [1-13C]malate and [1-13C]aspartate, is an important metabolic phenotype associated with increased hepatic glucose production in type 2 diabetes.