No sweat required! A hormone that surges during exercise may confer some of the benefits of a workout, when levels are artificially boosted.
The hormone is identical in mice and humans and promotes the development of a type of energy-burning fat – a discovery that could be key to treating obesity and diabetes.
A protein known as PGC1-alpha mediates many of the benefits of exercise, such as resistance to metabolic diseases. To find out more, a team of scientists analysed factors secreted by muscle and regulated by PGC1-alpha. One of these factors turned out to be a new hormone (named irisin) which had gone unnoticed because it is hidden within a complex molecule. Further study showed that levels of that hormone jumped in mice and humans after bouts of exercise. When the hormone was added to mouse subcutaneous white fat cells at an early stage of development, it made the cells more likely to become “beige” fat cells. These, like brown fat, are equipped to burn body fuel to generate heat.
Mice eating a high-fat diet that were given the gene for irisin burned more energy and had lower body weight than mice receiving a placebo. Learn more here.