Investigating the Mechanisms of Sarcopenia
Researchers continue to delve into the root causes of sarcopenia: "It is well known that the human aging process is associated with a progressive loss of muscular strength. Characteristic of this decline in muscle performance is the loss of skeletal muscle mass (sarcopenia) that occurs even in the healthy elderly. Indeed, humans can lose as much as 40% of their muscle mass from age 20 to 60. ... investigators used a combination of experimental approaches to phenotypically compare wild type old mice with mature mice lacking a novel muscle specific inositide phosphatase (MIP/MTMR14) that plays an important role in muscle calcium homeostasis. Interestingly, the mature MIP/MTMR14 knockout mice displayed phenotypes that closely resembled the muscles of old animals. Indeed, these relatively young knockout mice displayed impaired muscle calcium homeostasis, depressed muscle contractile force production and a loss of muscle mass that is commonly observed in senescent animals. Interestingly, the old wild type mice also displayed impaired muscle calcium homeostasis and decreases in muscle size and contractile function. Importantly, these old mice also possessed reduced muscle levels of MIP/MTMR14. The authors concluded that these findings were consistent with the hypothesis that an age-related loss in MIP/MTMR14 may be a contributory factor to sarcopenia."
Link: http://www.impactaging.com/papers/v2/n9/full/100193.html