Normalization of Diacylglycerol-Protein Kinase C Activation by Vitamin E in Aorta of Diabetic Rats and Cultured Rat Smooth Muscle Cells Exposed to Elevated Glucose Levels

• DOI: 10.2337/diab.43.11.1372
• Publication Date: 2013-09-19T17:22:06Z
• Authors: Makoto Kunisaki; Sven-Erik Bursell; Fumio Umeda; Hajime Nawata; George L King
• Keywords: Probucol; Intraperitoneal injection

Hyperglycemia and diabetes have been shown to increase diacylglycerol (DAG) level activate protein kinase C (PKC) activity in the vascular tissues, possibly altering function. We characterized effects of D-α-tocopherol (vitamin E) on PKC activities DAG levels rat aortic smooth muscle cells (ASMCs) cultured with elevated glucose as well tissues obtained from control diabetic rats. In ASMCs, specific membraneous fraction total were increased by 31 ± 4% (P < 0.05) 50 7% 0.05), respectively, when changed 5.5 22 mmol/1. The addition another lipophilic antioxidant, probucol, prevented glucose-stimulated increases activity. By immunoblotting studies, treatment was able reduce enhancement (ill isoform isolated ASMCs. Comparing streptozotocin-induced rats their nondiabetic controls, both membraneous-specific cellular aorta 162% 60% respectively. Intraperitoneal injection (40 mg/kg) every other day parallel a significant contents plasma. These findings demonstrated that can prevent activation induced hyperglycemia lowering levels, via its antioxidant effect.