Inflammation in Muscle Repair, Aging, and Myopathies

Numerous recent studies have expanded our knowledge on the complexity of the immune system and its contribution to skeletal muscle repair, aging, and myopathies. Indeed, it is becoming clear that a precisely regulated cross talk between muscle and immune cells, involving endocrine/paracrine and cell-cell contact interactions, is required for muscle repair and maintenance of muscle homeostasis.

The Basis of Muscle Regeneration

Muscle regeneration recapitulates many aspects of embryonic myogenesis and is an important homeostatic process of the adult skeletal muscle, which, after development, retains the capacity to regenerate in response to appropriate stimuli, activating the muscle compartment of stem cells, namely, satellite cells, as well as other precursor cells. Moreover, significant evidence suggests that while stem cells represent an important determinant for tissue regeneration, a “qualified” environment is necessary to guarantee and achieve functional results.

Mediators of Inflammation

"Responses of cells to stress include a wide range of molecular processes, induced by microenvironmental changes, which damage the structure and function of macromolecules. Depending on the kind, the severity, and the duration of stress encountered, cells respond by modulating signaling pathways leading to repair, to adaption, or to cell death. Such different choices have crucial effects on tissue homeostasis. Among cellular responses to stress, a prolonged inflammation may occur, ultimately leading to several pathological conditions, including cancer.