Protein blocking may be the key to an “exercise pill”
Suppressing production of the protein myostatin gives mice greater muscle mass and improves kidney function, writes Andrew Masterson.
Suppressing a particular protein might be the key to countering the negative health effects of obesity, according to research from Augusta University in Georgia, US.
Experiments conducted by Joshua Butcher of the university’s Vascular Biology Centre reveal that blocking the production of a protein called myostatin leads to enhanced muscle mass and improved kidney and heart health in obese mice.
Myostatin has long been known to damp down muscle growth. Obese mice (and people) typically produce more of it than those in normal weight ranges, resulting in a heightened inability to develop muscle mass. This, in turn, means that exercise becomes more difficult, effectively condemning the mouse (or person) to becoming ever more fat.
Butcher and his colleagues set out to test what would happen if the production of myostatin could be blocked. To do this they established four cohorts of mice: two lean and two obese variants, with myostatin blocked in one of each.
As expected, the effects of myostatin deletion were most pronounced in the obese cohort. While the protein-deficient obese mice did not lose any weight, they did develop significantly improved muscle mass.
They also recorded much lower blood pressure than the “normal” obese cohort, as well as markedly better urine sodium levels and urine micro-albuminuria ratios, indicating improved kidney function.
The same differences were recorded in the myostatin-deficient lean cohort, but to a much lesser extent, indicating that blocking the protein has a proportionately greater effect when body-mass index is at the upper end of the scale.
“In our muscular obese mouse, despite full presentation of obesity, it appears that several of these key pathologies are prevented,” says Butcher.
There is, of course, a long distance between initial mouse models and clinical applications in humans, but Butcher sees the potential for a peculiarly twenty-first century cure for obesity.
“Ultimately, the goal of our research would be to create a pill that mimics the effect of exercise and protects against obesity,” he says.
“A pill that inhibits myostatin could also have applications for muscle wasting diseases, such as cancer, muscle dystrophy and AIDS."
The research was presented at the annual Experimental Biology Conference held in San Diego, California.