WIKIMEDIA, JEPOIRRIER (FLICKR)A muscle gene activated by physical exercise protects the brains of mice from stress-induced depression, according to results published today (September 25) in Cell. Triggering this gene, PGC-1α1, blocks the transport of a metabolite that, within the brain, may cause inflammation that leads to depression. Understanding the biochemical reason why exercise improves symptoms in some patients with depression “opens up a very interesting therapeutic future,” said study coauthor Jorge Ruas of the Karolinska Institute in Sweden.
Previous studies have shown that physical exercise can prevent or improve the condition of many diseases, ranging from diabetes and obesity to mood disorders and depression. But whether the improvement stems from cardiovascular effects, muscle conditioning, or psychosocial benefits has been unclear.
In 2012, Ruas and his colleagues found that different forms of the skeletal muscle PGC-1α gene responded to different kinds of exercise. The gene could be transcribed from two different promoters: one version was responsive to resistance training, such as lifting weights, while the other, PGC-1α1, responded to endurance activity. To understand the different variants of the gene, the researchers created various mouse models that constitutively expressed different forms of these genes at high levels, as well as knockout lines. The animal models ...
