Ameliorative effect of the cinnamon oil from Cinnamomum zeylanicum upon early stage diabetic nephropathy.

The current study was designed to evaluate the ameliorative effect of the cinnamon oil upon early stage diabetic nephropathy owing to its antioxidant and antidiabetic effect. Cinnamon oil was extracted by hydro-distillation of the dried inner bark of Cinnamomum zeylanicum Blume. Further characterization of the extracted oil was carried out using IR, (1)H-NMR, and (13)C-NMR techniques. Early stage of diabetic nephropathy was induced by administration of alloxan (150 mg/kg, I. P.). Cinnamon oil was administered at varying doses (5, 10, 20 mg/kg; I. P.) while the level of fasting blood glucose, total cholesterol, high density lipoprotein, urea, thiobarbituric acid reactive substances, reduced glutathione, and catalase were determined. These parameters in cinnamon oil treated groups were compared with those of standard (glipizide; 10 mg/kg) and vehicle treated groups in order to investigate if cinnamon oil confers a significant protection against diabetic nephropathy. Histological studies of the kidney proved the protective effect of cinnamon oil by reducing the glomerular expansion, eradicating hyaline casts, and decreasing the tubular dilatations. Our results indicate that the volatile oil from cinnamon contains more than 98 % cinnamaldehyde and that it confers dose-dependent, significant protection against alloxan-induced renal damage, the maximum decrease in fasting blood glucose having been achieved at the dose of 20 mg/kg.