Combating Diabetes Mellitus and Associated Oxidative Stress with Indigenous Medicinal Plants

Diabetes mellitus (DM) is an endocrine disorder affecting more than 100 million people worldwide. It is exemplified by hyperglycemia caused by imperfect functioning of insulin, abnormal insulin secretion or sometimes the combination of both. The long-term persistence of high glucose concentrations in the blood leads to the generation of abnormally high level of free radicals and reactive oxygen species (ROS), change of various oxidative stress biomarker levels, simultaneous decline of antioxidant defense mechanisms and thereby causes a variety of diabetic complications in the body. Increasing evidence in both experimental and clinical studies suggests that oxidative stress plays a major role in the pathogenesis of both types of diabetes mellitus. Abnormally increased production of free radicals and the simultaneous decline of antioxidant defense mechanisms can lead to damage of cellular organelles and enzymes, enhanced lipid peroxidation, and development of insulin resistance, creating complicacies. Changes in oxidative stress biomarkers and their consequences are discussed in this chapter. In vivo studies of the effects of various conventional and alternative drugs on these biomarkers are surveyed. There is a need to continue to explore the relationship between free radicals, diabetes, and its complications, and to elucidate the mechanisms by which increased oxidative stress accelerates the development of diabetic complications, in an effort to expand treatment options. Many ethnobotanically important herbal plants possessing antihyperglycemic potential are known to exist in nature. Moreover, a large number of polyherbal formulations (PHFs) derived from these plants are presently being prescribed as medicinal/dietary supplements for the management of DM. It has become very much essential to explore the hidden active principles present in the traditionally used antidiabetic herbal plants in order to standardize the formulations of various herbal drugs for the betterment of both types of DM treatment. This chapter would well indicate about how oxidative stress is involved in the pathogenesis of diabetes and its complications. The experimental validations and biochemical aspects of traditionally used antidiabetic plants in phytotherapy of DM are discussed to understand and elucidate the antidiabetic as well as associated antioxidative potentials.

Keywords: Diabetes mellitus, oxidative stress, antioxidant, medicinal plant.