Von amyloid und entzündung: Was den muskel chronisch krank macht

Abstract

Classical inflammatory diseases of the skeletal muscle like polymyositis and dermatomyositis often lead to a rapid weakness of the muscles of arms and legs. The inflammation in the muscle is caused by immune cells and antibodies. Most patients respond well to standard immunosuppressive therapy. In sporadic inclusion body myositis (sIBM), similar pathomechanisms play a role, including cytotoxic T-lymphocytes, which attack and damage muscle fibers. At the same time, sIBM is characterized by an accumulation of aberrant molecules, particularly β-amyloid, which play a role in neurodegenerative diseases. This degeneration with formation of inclusion bodies and vacuoles may be the cause for the slowly, yet relentlessly progressive damage of the skeletal muscle and the lack of treatment efficacy of standard immunosuppression. Recent reports demonstrate that there is a specific interrelationship between inflammation with generation of mediators like interleukin (IL)-1β and the amyloid-associated degeneration. The molecular mechanisms discussed here are important for the future design of better treatment strategies for chronic muscle inflammation. Furthermore, these mechanisms can contribute to a better understanding of the pathogenesis of neurodegenerative diseases.