Evaluation of antidiabetic, antioxidant and antiglycating activities of the Eysenhardtia polystachya

BACKGROUND: Many diseases are associated with oxidative stress caused by free radicals. The aim of the present study was to evaluate the antidiabetic, antioxidant and antiglycation properties of Eysenhardtia polystachya (EP) bark methanol-water extract. MATERIALS AND METHODS: : The antioxidant capacities were evaluated by studying in vitro the scavenging of DPPH and ABTS free radical, reactive oxygen species such as RO(2), O(2)·(-), H(2)O(2), OH(.), H(2)O(2), ONOO-, NO, HOCl,(1) O(2), chelating ability, ORAC, β-carotene-bleaching and lipid peroxidation. The antiglycation activities of EP were evaluated by haemoglobin, bovine serum albumin (BSA)-glucose, BSA-methylglyoxal and BSA-glucose assays. Oral administration of EP at the doses of 100 mg/kg, 200 mg/kg and 400 mg/g was studied in normal, glucose-loaded and antidiabetic effects on streptozotocin-induced mildly diabetic (MD) and severely diabetic (SD) mice. RESULTS: EP showed Hdonor activity, free radical scavenging activity, metal chelating ability and lipid peroxidation Antioxidant activity may be attributed to the presence of phenolic and flavonoid compounds. EP is an inhibitor of fluorescent AGE, methylglyoxal and the glycation of haemoglobin. In STZ-induced diabetic mice, EP reduced the blood glucose, increased serum insulin, body weight, marker enzymes of hepatic function, glycogen, HDL, GK and HK while there was reduction in the levels of triglyceride, cholesterol, TBARS, LDL and G6Pase. CONCLUSIONS: Eysenhardtia polystachya possesses considerable antioxidant activity with reactive oxygen species (ROS) scavenging activity and demonstrated an anti-AGEs and hepatoprotective role, inhibits hyperglycemic, hyperlipidemic and oxidative stress indicating that these effects may be mediated by interacting with multiple targets operating in diabetes mellitus.