Effect of umbelliferone on tail tendon collagen and haemostatic function in streptozotocin-diabetic rats.

Diabetes mellitus is known to affect collagen in various tissues. Umbelliferone (7-hydroxycoumarin), a natural antioxidant and benzopyrone, is found in golden apple (Aegle marmelos Correa) and bitter orange (Citrus aurantium). Plant-derived phenolic coumarins have been shown to act as dietary antioxidants. In this study, we have investigated the influence of umbelliferone on collagen content and its effects on the tail tendon in streptozotocin-diabetic rats. Male albino Wistar rats (180-200 g) were made diabetic by intraperitoneal administration of streptozotocin (40 mg/kg). Normal and diabetic rats were treated with umbelliferone for 45 days. Diabetic rats had increased glucose and decreased insulin levels. Tail tendons of diabetic rats had increased total collagen, glycation and fluorescence, and decreased levels of neutral, acid and pepsin-soluble collagens. We have studied the effect of umbelliferone on haemostatic function because umbelliferone is also a coumarin derivative like the anticoagulant, warfarin. Diabetic rats had a significant decrease in prothrombin, clotting and bleeding time, and treatment with umbelliferone made these parameters almost normal. Our results show that umbelliferone controls glycaemia and has a beneficial effect on collagen content and its properties, i.e. collagen related parameters, in the tail tendon, which indicates recovery from the risk (recovery of animals from the risk of complications) of collagen-mediated diabetic polyneuropathy and diabetic nephropathy.