Plant Natural Products in Anti-Diabetic Drug Discovery

Plants and other natural sources have been useful in discovering drugs for treating patients with diabetes mellitus. Examples include the α-glucosidase inhibitor acarbose, and galegine, which contributed to the discovery and development of the biguanides. There are many traditionally used herbal medicines that lower blood glucose in experimental models, and, currently, there is considerable interest in exploring these plant extracts for compounds that might also be useful in the clinic or that might have novel effects, such as stimulation of β-cell proliferation. Often, neither their mechanism nor their active components have been defined, so it is possible that novel mechanisms of action and novel compounds will be discovered. In addition, there has been very little use of large collections of natural products in random screening campaigns against accepted therapeutic targets: there is great potential to find new chemical scaffolds for drugs with improved properties. This paper will provide an overview of recent activities relating to the use of natural products from plants as a source of compounds that might be beneficial in treating patients with diabetes.