Antidiabetic bioactive natural products from medicinal plants

Diabetes mellitus (DM), caused by either insulin resistance or abnormal insulin secretion, or both, continues to be one of the most prevalent endocrine disorders in the world. In fact, DM is the third most common cause of mortality and morbidity, next only to cancer and cardiovascular disorders. About 463 million people were said to have suffered from DM around the world in 2019. This number is soon to reach 548 million by the end of 2020 and is projected to be 700 million by 2045. Several studies have indicated that DM is found to be more prevalent in high-income countries and urban areas than in the rest. Typically characterized by multiple etiologies and a persistent state of hyperglycemia, DM is prone to cause multiple disorders, affecting several organs of the body. Its treatment, thus, proves to be quite tricky, requiring a multimodal approach. For instance, in order to manage the glucose levels of a DM patient, it is crucial to identify a whole host of individual factors that contribute toward the defective glycemic index. Of the many ways of effectively controlling and managing DM, several plant species and plant-based compounds play a pivotal role. It is against this backdrop that a review was conducted to ascertain the performance and characteristics of several plant-based bioactive compounds in the treatment of DM. It was found that the plant-based bioactive compounds exhibit a higher level of antidiabetic activity than that of non-plant-based hypoglycemic drugs. A compendious account of the review is provided here. It may be noted that though the review indicates the high level of antidiabetic activity of plant-based drugs such as polyphenols, alkaloids, flavonoids, coumarins, and terpenoids, attributing their derivatives to the corresponding plant structures, it does not include any discussion on structure-related activity.