Editorial: Molecular Mechanisms Protecting against Tissue Injury

In response to tissue injury acute inflammatory reactions occur that aim to restore homeostasis (Medzhitov, 2008). However, hampered resolution of inflammation can result in chronic inflammation and/or pathologic wound repair (Nathan and Ding, 2010). These conditions can result from excessive oxidative and inflammatory and/or overwhelmed adaptive response systems. They may also be triggered by a variety of other conditions including diabetes, infections, or aging. Targeted up-regulation of cytoprotective systems may be a therapeutic approach to ameliorate exacerbation of injury and prevent pathologic wound repair, fibrosis and/or cancer (Nathan, 2002). Such protective systems include various anti-oxidant, anti-inflammatory, anti-apoptotic molecules and also transporters or channels. In this Frontiers research topic various concepts how specific mechanisms can determine tissue damage or protection and their therapeutic potential in a number of pathological conditions and diseases are discussed. Tissue damage control is important at different levels to maintain homeostasis of cells, tissues and whole organisms. For example, when immunological reactions are primarily directed against the cause of tissue damage (e.g., pathogenic microbes), excessive collateral damage may occur. In such cases, avoiding additional tissue damage would be more important than elimination of the disease-triggering stimulus (Soares, 2014; Soares et al., 2014). Severe tissue injury can lead to chronic inflammation, fibrosis, disturbed developmental changes and cancer (Reuter et al., 2010), which underscores the need to prevent tissue damage and/or to promote regeneration. The coordinate immunological functions to maintain tissue homeostasis is orchestrated by a selected group of immune cells (Shalapour and Karin, 2015) such as dendritic cells (Mirzaee et al.) and regulatory T-cells (Lei et al.). Targeted modulation of these regulators may thus give control on the decisive machinery that determines immunity, inflammation, tissue remodeling, and cancer (Sutmuller et al., 2007). Infusion of regulatory T-cells facilitates tissue regeneration by preventing undesired immunological activity and by controlling resident non-immune tissue cells and forms an alternative strategy to dampen tissue injury (Lei et al.). Mizumura and colleagues describe how autophagy may promote tissue damage or repair and novel developments in its regulation (Mizumura et al.). In particular, the role of selective autophagy in a variety of human diseases and the therapeutic potential of this system is discussed. Surgery and other types of traumatic injury not only cause inflammatory injury, fibrosis, and scar formation (Brouwer et al., 2015), but are associated with the release of free heme (Wagener et al., 2003a). Heme is the prosthetic group of a number of …