How ground squirrels spend half of the year curled up without eating a thing and yet manage to maintain their protein balance, barely losing any muscle mass, has been a long-standing mystery. This is particularly remarkable given that prolonged periods of inactivity and fasting lead mammals’ bodies to get some energy by breaking down muscle proteins—a process known as muscle wasting.
A study published in Science today (January 27) offers a clue to this phenomenon: bacteria residing in the gut of thirteen-lined ground squirrels (Ictidomys tridecemlineatus) convert urea, a molecule that accumulates during muscle wasting, into nitrogen that can be used to build new proteins, potentially counteracting muscle loss. In addition to highlighting the role of microbes in hibernation, these findings may also inspire the development of microbiota-based therapies to treat human conditions where muscle wasting is common, such as malnutrition.
University of Alaska Anchorage ecologist and bioinformatician Kirsten Grond, ...
