Investigation of the Functional State of Heart Mitochondria in Inbred Mice with Type 2 Diabetes Mellitus

Diabetes mellitus is considered one of the most common metabolic diseases in the developed world and is associated either with impaired insulin secretion or with cell resistance to the action of this hormone (type 1 and 2 diabetes, respectively). In both cases, the common pathological change is an increase in blood glucose levels – hyperglycemia, which can ultimately cause serious damage to organs and tissues of the body. Mitochondria are believed to be one of the main targets of diabetes at the intracellular level. The present study addressed the functional state of mitochondria in the C57BL/Ks–db+/+m inbred mice carrying the recessive diabetes-db gene (diabetic mice). Histological analyses of the left ventricle of the hearts from diabetic and control mice were performed. In cardiac tissue samples from diabetic mice, an increase in the intensity of the eosin stain was observed implying that the structure of cytoplasmic proteins was distorted. In addition, it was shown that respiratory control and Ca2+ capacity in the mitochondria of diabetic mice decreased compared to controls. Changes in mitochondrial dynamics and mitophagy under these conditions were analyzed.