Role of antioxidants in phytomedicine with special reference to antidiabetic herbs

Diabetes mellitus is a severe health problem with continuously increasing rates of incidence and mortality and it may rise tremendously by 2025. This disease is characterized by elevated plasma glucose concentrations resulting from insufficient insulin and insulin resistance, or both, leading to metabolic abnormalities in carbohydrates, lipids and proteins. Free radicals are well known for their dual role as beneficial and toxic components, higher levels of free radicals causing damage to cellular proteins, membrane lipids and nucleic acids leads to cell death. Antioxidants are effective against free radicals by donating their own electrons. There is an increasing evidence confirmed that free radicals plays a crucial role in the pathogenesis of diabetes mellitus. Herbs are the well known source of non toxic antioxidants. The aim of the present review is to establish the role of free radicals in pathogenesis of various diseases with special consideration to diabetes mellitus. Further more recently reported herbs with antidiabetic action having antioxidant capacity is also with in the scope of this article.