Sex dependent differences in oxidative stress in the heart of rats with type 2 diabetes

Type 2 diabetes mellitus is known to double mortality from cardiovascular diseases (CVD), in which oxidative stress plays an important role. It is suggested that the impact of diabetes on CVD risk may vary depending on gender. The aim of the study was to assess oxidative stress parameters in the heart of 12 weeks old male and female Wistar rats with type 2 diabetes mellitus (T2DM) induced by high-calorie diet followed by intraperitoneal streptozotocin injections. The level of advanced oxidation protein products, superoxide dismutase, glutathione reductase and glutathione peroxidase activity in the isolated heart mitochondria and NADPH-oxidase and xanthine oxidase activity in the post-mitochondrial supernatant fraction were determined. It was shown that T2DM induced more pronounced oxidative stress confirmed by the increased level of advanced oxidation protein products in the heart mitochondria of males than females. The data obtained indicate that the main reason of oxidative stress in the heart of diabetic males is the activation of non-mitochondrial sources of reactive oxygen species. While in the heart of diabetic female rats it is the decrease in antioxidant enzymes activity in mitochondria. These results justify the necessity of gender-specific therapy for the prevention and management of diabetic CVD