Balancing the Fat Equation
Ronald M. Evans, Howard Hughes Medical Institute investigator and faculty at the Salk Institute for Biological Studies, discusses proteins called PPARs (peroxisome proliferator-activator receptors), which controls how the body uses sugar and fat. PPAR-gamma drives the formation of fat cells and regulates the storage of fat. It encourages muscles to burn sugar and maintains insulin sensitivity. PPAR-delta regulates how muscles burn fat by stimulating cellular fat-burning pathways and increasing slow-twitch muscle mass. Mice that are engineered to produce an overactive version of this receptor in their muscle tissue remain sleek and lean. On a treadmill, these "marathon mice" run twice as far as normal mice. Drugs that stimulate PPARs might help people slim down and improve health without altering appetite.