Exercise enhances wound healing and prevents cancer progression during aging by targeting macrophage polarity

Abstract

Physical activity, which can include regular and repetitive exercise training, has been shown to decrease the incidence of age-related diseases. Aging is characterized by aberrant immune responses, including impaired wound healing and increased cancer risk. The behavior and polarized phenotype of tissue macrophages are distinct between young and old organisms. The balance of M1 and M2 macrophages is altered in the aged tissue microenvironment, with a tilt towards an M2-dominant macrophage population, as well as its associated signaling pathways. These M2-type responses may result in unresolved inflammation and create an environment that impairs wound healing and is favorable for cancer growth. We discuss the concept that exercise training can improve the regulation of macrophage polarization and normalize the inflammatory process, and thereby exert anticancer effects and enhance wound healing in older humans. © 2014 Elsevier Ireland Ltd.