Metformin: Beyond Diabetes

In the world of drug repositioning metformin has a prominent place. This anti-diabetic medication which belongs to the family of biguanides has been prescribed for more than 60 years in Europe. Recently, metformin has generated lot of excitement with the discovery of potential therapeutic effects in addition to its antidiabetic properties. In some studies metformin use has been associated with a reduced risk of cancer and cardiovascular disease, findings that are also supported by preclinical studies in cells and experimental models. The keen interest for this drug and its low cost have led clinicians to initiate many trials, with more than 150 registered for cancer or cardiovascular disease therapy and prevention. The revival of metformin encompasses a growing number of pathologies and this Research Topic will address these broad scientific and clinical aspects of metformin action beyond diabetes. As the first line treatment for type 2 diabetes, metformin is one of the top prescribed drugs in the world. It decreases hyperglycemia and thus hyperinsulinemia, in addition to its systemic effects. Metformin inhibits the respiratory chain of the mitochondria, disrupting energy supply in cancer and other cells. These actions may contribute towards the anti-tumoral action of the drug and may also contribute towards the extended lifespan observed in animal models treated with metformin. Metformin has also an impact on pathologies associated with ageing, indeed, several epidemiological and pre-clinical studies have shown that metformin may be beneficial in Alzheimer’s disease, stroke and other degenerative brain diseases. More recent studies have reported metformin-induced changes in gut microbiota that may contribute towards metformin’s benefits on metabolism. Finally, the anti-inflammatory and anti-infectious properties of the drug have reinforced metformin as an attractive candidate for drug repurposing.

This Research Topic collection aims to provide an up-to-date summary of recent advances on metformin biology and clinical studies in nondiabetic pathologies. It will encourage, with no limitations, reviews on: epidemiology and clinical trials, alongside those on preclinical studies of drug mechanism.