Antihyperglycemic and antihyperlipidemic activity of ethyl acetate fraction of Rhododendron arboreum Smith flowers in streptozotocin induced diabetic rats and its role in regulating carbohydrate metabolism

<p><b>OBJECTIVE</b>To explore and identify the most potent antihyperglycemic fraction from the ethanol extract of Rhododendron arboreum (R. arboreum) flowers.</p><p><b>METHODS</b>Normal and streptozotocin induced diabetic rats were treated with all four fractions of R. arboreum flowers for short term and with fraction 3 for long term study. On completion of the treatment, a range of indicators were tested including fasting blood glucose, plasma protein, haemoglobin A1C, insulin secretion, body weight, blood lipid profile and carbohydrate metabolism regulating enzymes of liver.</p><p><b>RESULTS</b>In short term study, the fraction 3 (Active fraction) produced a significant (P<0.000 1) reduction (73.6%) in blood glucose level at a dose of 200 mg/kg after the treatment in the diabetic rats. Administration of active fraction (200 and 400 mg/kg) once daily for 30 d in streptozotocin diabetic rats resulted in a significant (P<0.001 to P<0.000 1) fall in blood glucose level, hemoglobin A1C, serum urea and creatinine with significant but a increase in insulin level similar to standard drug glybenclamide. Further, the active fraction showed antihyperlipidemic activity as evidenced by significant (P<0.001 to P<0.000 1) decreases in serum serum total cholesterol, triglycerides, low density lipoprotein cholesterol and very low density cholesterol levels coupled together with elevation of high density lipoprotein cholesterol in the diabetic rats.</p><p><b>CONCLUSIONS</b>The active fraction of R. arboreum flowers decreases streptozotocin induced hyperglycemia by promoting insulin secretion and glycolysis and by decreasing gluconeogenesis.</p>

Antihyperglycemic activity, antihyperlipedemic activity, haematological effects and histopathological analysis of Sapindus mukorossi Gaerten fruits in streptozotocin induced diabetic rats

OBJECTIVE@#To investigate the antihyperglycemic and antihyperlipidemic properties of hydroalcoholic extract of fruits of Sapindus mukorossi Gaerten and its beneficial effect on haematological parameters with histopathological analysis in streptozotocin induced diabetic rats.@*METHODS@#Sapindus mukorossi fruits extract (250 and 500 mg/kg body weight) and standard drug glybenclamide (0.5 mg/kg body weight) were administered to diabetic rats. Effect of extract on hyperglycemia, hyperlipidemia and hematological parameters was studied in diabetic rats. Histopathological changes in diabetic rat pancreas were also observed after extract and glybenclamide treatment.@*RESULTS@#Daily oral administration of Sapindus mukorossi fruits extract (250 and 500 mg/kg body weight) and glybenclamide for 20 days showed beneficial effects on blood glucose level (P<0.01) and lipid level. The extract has a favorable effect on the histopathological changes of the pancreas in streptozotocin induced diabetes.@*CONCLUSION@#These findings reveal that the hydroalcoholic extract of Sapindus mukorossi fruits extract possesses antihyperglycemic and antihyperlipidemic properties. In addition, the extract can prevent various complications of diabetes and improve some haematological parameters.