Effects of melatonin administration on blood coagulability and lipid profile in experimentally diabetic albino rats

Diabetes is associated with high incidence of atherosclerosis due to the significant dyslipideamia and the increased platelet adhesiveness with increased tendency for coagulation. In this study the effects of melatonin, the hormone of the pineal gland, on the blood coagulability and lipid profile was investigated in experimentally diabetic rats. The rats in this study were divided into 4 groups: group I [control], group II [control + melatonin], Group III [diabetic] and group IV [Diabetic + melatonin]. Melatonin was administered in group II and IV orally as a single daily dose of 30 mg/kg body weight for one month. The results of this study revealed that, melatonin induced a significant decrease in serum TG, LDL levels accompanied with a significant increase in serum HDL, which was associated with an insignificant effect on serum cholesterol. Moreover, melatonin administration provoked a significant increase in bleeding time, prothrombin time and partial thromboplastin time accompanied with a significant inhibition in platelet aggregation, which was associated with an insignificant effect on platelet number. In conclusion, melatonin has a protective effect in diabetic patients and it can reduce the incidence of clot formation and coronary heart diseases, which are more common in those patients

Effects of melatonin treatment on markers of endothelial dysfunction in streptozotocin induced diabetes in rats

Diabetes mellitus is a very common health problem with a great impact in the individual health. Insulin dependent diabetes mellitus [IDDM] is believed to result from destruction of pancreatic beta cells secondary to toxic effects of free oxygen radicals, The diabetic patients are at a significant increase risk of developing cardiovascular diseases in general and coronary diseases in particular. The oxidative stress may play an important role in the etiology of diabetic complications. This oxidative stress is opposed by abundant supply of antioxidants. The antioxidants may play an important role in regulation of the level of plasminogen activator inhibitor 1 [PAI-1] which plays an important role in regulation of fibrinolysis. Also the fibrinolytic capacity of human blood is the result of a balance between plasminogen activators and inhibitors. The reent work was designed to study the effect of melatonin [antioxidant] treatment for eight weeks on serum levels of plasminogen activator inhibitor01 [PAI-I], Von willebrand factor [vwf], factor VII and triacylglycerol in streptozobtocin diabetic rats. Forty five adult male rats were divided into thee equal groups one served as a control, the other two groups were rendered diabetic by a single intraperitoneal injection of 50 mg/kg body weight streptozotocin [STZ]. One remained diabetic without melatonin treatment while the other group was given daily dose of 0.27 mg/kg. B.W. melaonin for eight weeks. Diabetic rats showed a significant increase in serum level of triacylglycerol, PAI-I, [vwf] and factor VII showed slight increase compared to non diabetic group. Treatment of diabetic rats with melatonin induced a significant decrease in serum levels of triacyglycerol, PAI-1, [vwf] and factor VII showed non significant decrease compared with diabetic group. We concluded that melatonin therapy induced a beneficial effect in STZ diabetic rats especially in a pattern of changes in serum levels of triacylglycerol, and the markers of endothelial dysfunction [PAI-I and vwf] that are related to induced risk of atherosclerosis