Effect of crocin on antioxidant gene expression, fibrinolytic parameters, redox status and blood biochemistry in nicotinamide-streptozotocin-induced diabetic rats.

Background: Diabetes is regarded as an epidemiological threat for the twenty-first century. Phytochemicals with known pharmaceutical properties have gained interest in the field of alleviating secondary complications of diseases. Such a substance is crocin, a basic constituent of saffron (Crocus sativus). The present study aimed at examining the beneficial effects of per os crocin administration on the antioxidant status, blood biochemical profile, hepatic gene expression and plasminogen activator inhibitor-1 activity (PAI-1) in the liver, kidney and plasma (an important marker of pre-diabetic status and major factor of thrombosis in diabetes) of healthy rats, as well as of rats with nicotinamide-streptozotocin-induced diabetes.

Results: Diabetes disrupted the oxidation-antioxidation balance, while crocin improved the antioxidant state in the liver by significantly affecting SOD1 gene expression and/or by restoring SOD and total antioxidant capacity (TAC) levels. In the kidney, crocin improved hydrogen peroxide decomposing activity and TAC. In blood, hepatic transaminases ALT and AST decreased significantly, while there was a trend of decrease regarding blood urea nitrogen (BUN) levels. The expression of PAI-1 gene was affected in the liver by the dose of 50 mg kg^-1.

Conclusions: Crocin treatment contributed in restoring some parameters after diabetes induction, primarily by affecting significantly hepatic transaminases ALT and AST, SOD1 and PAI-1 gene expression and nephric H₂O₂ decomposing activity. In conclusion, crocin did contribute to the alleviation of some complications of diabetes.