Catechin attenuates diabetic autonomic neuropathy in streptozotocin induced diabetic rats

Abstract

Diabetic autonomic neuropathy (DAN) is one of the least understood and attended complications which affects the quality of life. Increased oxidative stress, advanced glycation end products (AGEs), overactivation of protein kinase C (PKC) and reduced myoinositol content in autonomic nerves are major pathological conditions responsible for DAN. Limited treatment options appeal researchers to search for alternative treatments for DAN. Natural polyphenols are potent antioxidants and have been reported to have beneficial effects in above mentioned pathological conditions. Diabetes was induced in male Sprague Dawley rats weighing between 190-220 g with streptozotocin (55 mg/kg, i.p.). After 6 weeks of diabetes induction, animals were treated with catechin at dose 25 and 50 mg/kg for the next 28 days. Catechin treatment at dose 25 and 50 mg/kg showed significant improvement in body weight. The treatment with catechin at dose 50 mg/kg; significantly reduced heart hypertrophy (p < 0.001) and plasma glucose levels (p < 0.01). At dose 50 mg/kg catechin significantly improved hemodynamic parameters like heart rate, mean atrial pressure and left ventricular systolic pressure. Catechin also improved oxidative stress parameters in the nerves. Circulatory MMP-9 levels were significantly decreased (p < 0.001) in catechin treated animals at a dose of 50 mg/kg. The histopathology results showed a significant reduction in neuronal damage due to catechin treatment for 28 days. The results of the study showed that catechin has a beneficial effect in the management of diabetic autonomic neuropathy in rats.

Keywords: Cardiac autonomic neuropathy; Catechin; Diabetic autonomic neuropathy; Extracellular matrix modulation; Flavonoids; Polyphenols.