Muscle stem cells in skeletal muscle

Skeletal muscle fulfills a multitude of functions in the organism, among them voluntary movements. Furthermore, skeletal muscle has a remarkable ability to adapt and to regenerate. For instance, the size of myofibers – the units which are responsible for the movement of skeletal muscle – can be adapted due to physical exercise or disuse. With increasing age, plasticity of skeletal muscle is reduced concomitant with an altered ability to regenerate. Muscle stem cells, also called satellite cells, are essential for regeneration of skeletal muscle. Under resting conditions muscle stem cells are quiescent but are activated due to increased muscle activity or damage of skeletal muscle. During regeneration of skeletal muscle the cells proliferate and undergo myogenic differentiation and subsequent fusion resulting in the formation of newly formed myofibers. During aging muscle stem cells and their immediate niche undergo alterations. Our research group investigates those intrinsic alterations and alterations in the immediate muscle stem cell niche with the aim to identify signaling pathways which are altered during aging to rejuvenate aged muscle stem cells. The final goal of our work is the restoration of homeostasis of muscle stem cells and the treatment of sarcopenia, the age related loss of muscle mass and function.