Metformin: A Small Molecule with Multi-Targets and Diverse Therapeutic Applications

Metformin is one of the most prescribed agents in the treatment of type 2 diabetes. Its history goes back to the use of goat’s rue (Galega officinalis Linn., Fabaceae). G. officinalis is rich in galegine, a guanidine derivative with a blood glucose-lowering effect. Research based on the effects of guanidine rich on this traditional herbal medicine led to the development of metformin. Metformin continues to serve as a multi-target drug. Its benefits for treating/controlling several diseases were thoroughly discovered over time. These include health disorders such as cancers, obesity, periodontitis, cardiovascular, liver, skin, and renal disorders. Moreover, there is evidence to propose that metformin postpones the aging processes as well as modulates the microbiota to promote better health. So far, it is not fully understood, how metformin can accomplish such pleiotropic pharmacological and therapeutic effects. Metformin may decrease malignancy via suppressing the signal of insulin/IGF-1, avoiding the release of cytokines via NF-κB, and increasing the immune reaction to cancer cells. This chapter discusses the history of metformin discovery, chemistry, its role in diabetic patients, and proposed molecular mechanisms to shed more light on the diverse effects and its ability to target multiple signaling pathways.