No workout? No worries: Scientists prevent muscle loss in mice, despite disease and inactivity

"The loss of muscle mass is a major contributor to disease-related deaths," said Andrew R. Judge, Ph.D., a researcher involved in the work from the Department of Physical Therapy at the University of Florida in Gainesville. "FoxO proteins may provide a target for therapies aimed at reducing muscle wasting and thus improving the quality of life and survival rates for patients with many different diseases."

To make this discovery, Judge and colleagues genetically inhibited the activity of "Forkhead boxO" proteins, or "FoxO," in the skeletal muscle of healthy control mice, septic mice, and mice with cancer. The loss of muscle mass in those with cancer and sepsis was significantly decreased by inhibition of FoxO activity. In healthy control animals inhibiting FoxO activity caused an increase in muscle cell size which occurred as a result of protein synthesis.

"No one can deny that the human body was meant to move, and to move often," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal, "but the reality is that many of us don't move enough, whether because of disease, injury, or simply a busy schedule. This discovery is another important step towards the treatment of muscle wasting in cancer, severe infection or aging – or to maintain our muscle mass to help face the slings and arrows of outrageous fortune."

More information: Sarah A. Reed, Pooja B. Sandesara, Sarah M. Senf, and Andrew R. Judge. Inhibition of FoxO transcriptional activity prevents muscle fiber atrophy during cachexia and induces hypertrophy. FASEB J March 2012 26:987-1000; doi:10.1096/fj.11-189977

Provided by Federation of American Societies for Experimental Biology