Changes in biomarkers of endothelial function in the blood after intracerebral hemorrhage in rats with type 2 diabetes mellitus

Abstract

Clinical evidence suggests that type 2 diabetes mellitus can increase the risk of intracerebral hemorrhage and provocation of neurodegeneration. This study was aimed at evaluating biomarkers of glycemic control, lipid profile, oxidative modification of proteins, as well as the functional state of endothelium in Wistar rats with type 2 diabetes mellitus complicated by intracerebral hemorrhage. Experimental type 2 diabetes mellitus was induced by intraperitoneal injection of streptozotocin (65 mg/kg) and nicotinamide (230 mg/kg). The intracerebral hemorrhage was induced by microinjection of sterile saline containing 0.2 IU bacterial collagenase into the striatum. Assessed biomarkers included the area under glycemic curve, glycated hemoglobin, total cholesterol, triglyceride, high-density lipoprotein, advanced glycation end products, markers of oxidative modification of proteins – aldehyde- and ketonephenylhydrazones, and markers of endothelial dysfunction – homocysteine, endothelin-1, von Willebrand factor and asymmetric dimethylarginine in blood serum. Both rats with type 2 diabetes mellitus and rats with intracerebral hemorrhage and diabetes had a significant elevated glycemic control as compared to intact animals. But combined pathology was additionally characterized by an impairment of lipid profile (increased triglyceride level and decreased as total cholesterol and high-density lipoprotein) resulting in a rise in the atherogenic index of plasma. A significant increase in the content of the markers of oxidative modification of proteins was observed in both experimental groups. But the rats with intracerebral hemorrhage and diabetes only had higher levels of advanced glycation end products in comparison with intact animals. The highest levels of endothelin-1, as a biomarker of endothelial dysfunction, were observed in animals with intracerebral hemorrhage and diabetes. Homocysteine and von Willebrand factor were elevated in rats with type 2 diabetes mellitus, while acute intracerebral hemorrhage did not potentiate the further growth in its levels. Such effect was not accompanied by a marked increase of asymmetric dimethylarginine level in blood serum, although there was a clear trend. In conclusion, the development of intracerebral hemorrhage in rats with type 2 diabetes mellitus can intensify the manifestations of oxidative stress, worsen lipid profile, and aggravate endothelial dysfunction. In this case, the pathological process may have the character of a “vicious circle”.