Pterocarpus marsupium extract reveals strong in vitro antioxidant activity

Diabetes mellitus is a complex chronic disease characterized by hyperglycemia, which via several mechanism leads to an increase in production of reactive oxygen species (ROS) leading to various secondary complications. Thus, a drug having both antidiabetic and antioxidant properties would have great therapeutic value for overcoming the oxidative load in diabetes. The present study was aimed at extensively evaluating the antioxidant properties of an anti-diabetic plant extract of stem bark of Pterocarpus marsupium using various in vitro radical scavenging assays as well as by using liver slice cultures as a model system. Our results demonstrate that the whole aqueous extract showed high antioxidant activity in all different assays used and also protected mitochondria against oxidative damage. Ethanol was used as an inducer of oxidative stress in liver slice culture and cytotoxicity was estimated by quantitating release of cytotoxicity marker enzymes such as lactate dehydrogenase (LDH). Additionally, levels of antioxidant enzymes (AOEs) namely superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were also estimated. The whole aqueous extract significantly reduced LDH release along with reduction of lipid peroxidation compared to ethanol treated slices. These results indicate that the P. marsupium extract may serve as a potential source of natural antioxidant for treatment of diabetes.