Research Outcomes of Natural Products in Diabetes Mellitus

Diabetes mellitus, is a chronic condition with dysregulated glucose levels and has been affecting a larger global population. The disease, if not controlled, can lead to several microvascular and macrovascular complications that will impede the patients' physical and mental well-being in addition to its economic burden. Many diabetic patients are unaware of the complications and hesitate to take medicines in the early phase of the disease condition. Furthermore, many patients have limited access to conventional antidiabetic drugs, which drives the search for newer agents or relying on alternative/complementary medicines. Ancient systems such as Ayurveda, traditional African and Chinese medicine, Japanese Kampo medicine, and other systems of medicine have identified many herbal/plants, and mineral-based agents for treating diabetes. Many such plants probably more than 800 and their extracts have been scientifically proven or tested using various experimental models of diabetes in animals. Despite several In vitro and In vivo studies reporting the effects of extracts of plants on blood glucose, only a few trials have been performed to validate their efficacy in treating humans with diabetes. An apparent mismatch in outcomes was observed while translating the effectiveness of these plants from an experimental animal study to a human study. These inconsistencies among animal and human studies were remarkable in some cases. There are several aspects responsible for these variations, such as variation in plant parts/extracts, dose, duration in different studies, the difference between animal models and human disease, and initiation of drug treatment in animal model, which is generally before the induction of diabetes or immediately after the induction of diabetes. This chapter focuses on the animal studies and human clinical trials conducted on plant-based extracts and other natural products and the outcomes in controlling or managing diabetes mellitus.