The Presence of Oxygen in Wound Healing

Howard M. Kimmel, DPM, MBA; Anthony Grant, DPM; James Ditata, BSN, RN, CNOR

Disclosures

Wounds. 2016;28(8):264-270. 

In This Article

Oxygen at the Molecular Level

In the aerobic metabolism of glucose, cells use oxygen as the final electron acceptor to generate adenosine triphosphate (ATP), which fuels the majority of cellular processes during wound healing.[2] Healing tissue requires an increased energy demand.[3] This additional energy is generated from the oxidative metabolism which in turn increases the oxygen demand of the healing tissue.[4] Thus, the ATP that is generated from this process helps supply the power for tissue repair. During the inflammatory phase of wound healing, platelets and disintegrating cells can contribute ATP.[5] This extracellular ATP can act as a signalling mechanism for many aspects of wound healing such as the immune response, inflammation, epithelial cells, and angiogenesis.[6] When ATP is released during an injury to the skin, it acts as an early signal in an epidermal-like growth factor which, downstream, signals epidermal growth.[7] Another signalling function of ATP is that it is released from the cells in the injured tissue, thereby activating nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which is required to produce the redox signals in wound healing.[8] The first discussion of the killing of bacteria by an oxidase occurred in 1978.[9] When the phagocytosis of bacteria occurs, the immune system increases oxygen consumption through NADPH oxidase that in turn generates metabolites.[10] These metabolites catalyse the production of a reactive oxygen species (ROS) by cells that then stimulate a high demand for oxygen or "respiratory burst."[11] The majority of the oxygen consumed by neutrophils occurs during this respiratory burst.[12] Nicotinamide adenine dinucleotide phosphate oxidase is vital in the survival of macrophages, and it also enables phagocytosis of dead cells.[13]

processing....