Chemical in apple peel strengthens muscle
An apple a day really does keep the doctor away according to a new study in mice. A constituent of apple peel called ursolic acid has been found to reduce muscle wasting, also known as muscle atrophy, and promote muscle growth. Muscle atrophy affects most people at some point during their lives, either through aging or during illness.
Mice that received ursolic acid in their diet had larger and stronger muscles. However, interestingly, the increased muscle mass did not increase their overall body weight because these mice had less body fat than those that were not fed the compound. Ursolic acid was also found to reduce their blood sugar levels, cholesterol and triglycerides.
On analysing patterns of gene expression the researchers found that cultured cells treated with ursolic acid possessed opposite expression patterns to those found in cells experiencing atrophy. Ursolic acid could therefore reverse atrophy. The study suggests that this could be due to its ability to influence the binding of hormones IGF1 and insulin to muscle cells, which alters muscle gene expression in such a way that atrophy is reduced and muscle growth is promoted.