Metformin, Microbes, and Aging

The mechanisms underlying the biological activity of metformin, a widely prescribed drug to treat type 2 diabetes, remain elusive. In a recent issue of Cell, Cabreiro et al. report that in C. elegans, metformin indirectly impacts lifespan by altering the methionine metabolism of its microbial partner E. coli (Cabreiro et al., 2013).