42 have attributed a key role to calpains in the early stages of muscle protein degradation [41]. Indeed, the calcium- dependent proteases participate in the release of the myofilaments from the sarcomere; these myofilaments would later be degraded by the ubiquitin-dependent proteolytic system [41]. Very recently, a role for lysosome activity in muscle degradation during cancer cachexia has been also pointed out. Indeed, activation of FoxO3 stimulates lysosomal proteolysis in muscle by activating autophagic-related genes [42]. It is well-known that FoxO3 is one of the main transcription factors involved in the activation of atrogenes, a family of genes responsible for triggering atrophy in skeletal muscle [43]. From the results presented here, it can be concluded that exploring the inhibition of the myostatin system could well be an optimal strategy, particularly in combination with a nutritional approach, for the amelioration of a cachectic syndrome in humans. 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