Immune system and sarcopenia: Presented relationship and future perspective.

Sarcopenia, a geriatric syndrome that is characterized by a progressive and generalized skeletal muscle disorder, can be associated with many comorbidities, including obesity, diabetes, and fracture. Currently, the importance and urgency of sarcopenia have gained more consensus. Discovering the mechanisms of sarcopenia has been more and more important. It has been previously suggested that immune system during ageing plays an important role in the progression of sarcopenia. Immune ageing, which is often highlighted in elder individuals, may be an important contributor in sarcopenia. Immune ageing can occur in different aspects. The alteration in immune organs can affect both the innate immunity and adaptive immunity, affecting the whole condition of the body through circulation. Several kinds of immune cells, including lymphocytes, macrophages, neutrophils and other immune cells, together alters the situation of muscle fiber, causing muscle weakness, loss of muscle strength and muscle mass. Synergistic and cumulative effect of cytokines, such as TNF-α and IFN-γ, interrelates with obesity and diabetes, impairing the condition of skeletal muscle tissue and leading to deterioration of sarcopenia. Studying the relationship of sarcopenia and immune system offers great potential in future studies. Thoroughly studying these mechanisms can help to better determine an ideal scheme and better management of sarcopenia and its associated comorbidities, which tends to offer deeper insight and guidance in treating sarcopenia through alterations of food intake, exercise and medical intervention.