Antidiabetic Drugs: Mechanisms of Action and Potential Outcomes on Cellular Metabolism

Diabetes mellitus (DM) is one of the most prevalent chronic diseases and has been a leading cause of death in the last decades. Thus, methods to detect, prevent or delay this disease and its co-morbidities have long been a matter of discussion. Nowadays, DM patients, particularly those suffering with type 2 DM, are advised to alter their diet and physical exercise regimens and then proceed progressively from monotherapy, dual therapy, and multi-agent therapy to insulin administration, as the disease becomes more severe. Although progresses have been made, the pursuit for the "perfect" antidiabetic drug still continues. The complexity of DM and its impact on whole body homeodynamics are two of the main reasons why there is not yet such a drug. Moreover, the molecular mechanisms by which DM can be controlled are still under an intense debate. As the associated risks, disadvantages, side effects and mechanisms of action vary from drug to drug, the choice of the most suitable therapy needs to be thoroughly investigated. Herein we propose to discuss the different classes of antidiabetic drugs available, their applications and mechanisms of action, particularly those of the newer and/or most widely prescribed classes. A special emphasis will be made on their effects on cellular metabolism, since these drugs affect those pathways in several cellular systems and organs, promoting metabolic alterations responsible for either deleterious or beneficial effects. This is a crucial property that needs to be carefully investigated when prescribing an antidiabetic.