Moringa oleifera Attenuates Oxidative Stress in STZ-Induced Diabetic Rats

Hyperglycemia in diabetes has been associated with increased formation of reactive oxygen species (ROS). Imbalance between formation and detoxification of ROS in biological systems exerts oxidative stress. Oxidative stress damages tissue compounds like DNA, protein and lipid. Moringa oleifera is a rich dietary source of natural antioxidants. The aim of this study is to evaluate the effect of leaves, stems and pods extracts of M. oleifera on lipid peroxidation, protein oxidation and antioxidant power in plasma as well as in liver in streptozotocin (STZ) induced diabetic rats. At the end of the treatment period, the levels of plasma glucose, HbA1C and Thiobarbituric acid reactive substances (TBARS) increased and free radical absorption power (FRAP) decreased in diabetic rats compared to normal rats. Administration of Moringa leaves extract (MLE), Moringa stems extract (MSE) and Moringa pods extract (MPE) for 4 weeks caused significant decrease in plasma glucose, HbA1C, plasma and liver TBARS, and an increase in levels of FRAP (both plasma and liver) in diabetic treated rats compared to untreated-diabetic rats. Phytochemical screening of the extracts revealed the presence of flavonoids, tannins, saponins, phenolic compounds and reducing sugar. Flavonoid and phenolics rich extracts MLE and MPE showed better attenuation of oxidative stress in diabetic rats. The trend was MLE>MPE>MSE. The present study confirms potential efficacy of M. oleifera in suppressing oxidative stress induced by hyperglycemia in rats.