Streptozotosin Diyabeti Oluşturulan Ratlarda Protein Oksidasyonunun Değerlendirilmesi

Abstract

Aim: Diabetes mellitus (DM) is a chronic disorder and characterized by the development of long-term complications. Methylglyoxal (MGO), a precursor of advanced glycation endproducts (AGE), is detoxified in the organism by Glyoxalase through Glyoxalese I (GLO I) and GLO II.This study was aimed to investigate AGE formation in a diabetic rat model induced by streptozotocin (STZ) and the possible role of melatonin MEL which is a powerful antioxidant in this mechanism.Materials and Methods:Four study groups, each containing ten Sprague Dawley rats, were defined as control, MEL, STZ and STZ-MEL. STZ and STZ-MEL groups were given a single 50 mg/kg dose of STZ to induce diabetes. MEL, 25 mg/kg was given intraperitoneally to MEL and STZ-MEL groups on a daily basis for 42 days. At the end of study, the levels of MGO, GLO I and GLO II enzymes were also determined in only tissue samples.Results: Blood and urine glucose levels were found to be high in rats (p<0.05). STZ group had been shown to have higher tissue MGO levels and lower GLO I and GLO II activities (p<0.05). MEL treatment had suppressed high levels of MGO and increased enzymatic activities in STZ-MEL group.Conclusion: In this study, we have shown that reducing MGO tissue levels in chronic diabetes to almost normal level and that the GLO system suppressed in diabetic rats are preserved with MEL,GLO I and GLO II activities increased. It has been shown that STZ induced diabetic rats had high MGO levels and the supression of GLO detoxification system indicates that AGE formation in diabetes is inevitable. Therefore, the usage of antioxidants such as MEL may be suggested to prevent diabetic complications.