당뇨병성 백서에서 Vanadate투여후 혈당의 변화와 근육세포내 포도당운반체 활성도 및 유전자의 조절

Abstract

Objectives: Vanadate is known to mimic several effect of insulin including the stimulation of glucose uptake and oxidation, glycogen synthesis as well as the anti-lipolytic effect. But mechanisms for these effects of vanadate are still not completely understood. The aim of this study was to elucidate the effects of vanadate on intrinsic activity of the glucose transporter and the regulation of the glucose transporter mRNA. Methods: Using age and weight-matched male Sprague-Dawley rats (average weight 250 g), the experimental groups were divided into nondiabetic rats (n= 6), streptozotocin (STZ)-induced diabetic rats (n=6), metavanadate and pervanadate treated diabetic rats (n =12). We measured weight, blood glucose, glucose transporter activity, and glucose transporter 4 (GLUT4) mRNA change. Results: 1) STZ-induced diabetic rats became catabolic and they lost their weight, but after 3 to 4 weeks of treatment with metavanadate or pervanadate, body weights were increased. Blood glucose levels in metavanadate or pervanadate treated rats were significantly lower than STZ-induced diabetic rats after 1 week treatment. 2) There was no significant toxicity in vanadates treated rats, compared with STZ-induced diabetic rats and there was no abnormal change in kidney and liver of rats under light microscope 8 weeks after vanadates treatment. 3) The glucose transporter activity of diabetic rats was significantly decreased, compared with that of normal control rats, and increased after vanadates treatment. 4) The glucose transporter mRNA of diabetic rats was markedly decreased, compared with that of normal control rats, and increased after vanadates treatment. Conclusion: In STZ-induced diabetic rats, vanadates treatment may improve insulin sensitivity through in- creased expression of GLUT4 gene.