The role of ultraviolet radiation in the repair of skin damage

Type:Uv phototherapy   Time:2018-10-16 21:15:20
Ultraviolet rays have anti-inflammatory, analgesic and regenerative effects. Appropriate doses of UV can stimulate epidermal cell proliferation and promote the release of immune factors, but high doses of UV light can cause skin aging, thickening of the stratum corneum, and even cancer and low immunity. Wound repair involves the elimination of damaged tissue and the accumulation of various cells, local production of large amounts of collagen matrix, and finally the formation of scars. A variety of cells, matrix components, vascular and polypeptide growth factors are closely related to the wound repair process. It is generally believed that ultraviolet radiation promotes wound healing due to: direct bactericidal action of ultraviolet light; photochemical reaction of skin after irradiation, skin erythema, local vasodilation, hyperemia, blood flow, tissue blood perfusion, cell metabolism, stimulating cells The synthesis of DNA and RNA promotes cell mitosis and growth. Studies have shown that UV irradiation can also stimulate skin keratinocytes to produce various cytokines such as IL-1, IL-6, bFGF, PDGF, TGF and TNF-¦Á. These factors can neutrophil, mononuclear-macrophage system, stimulate fibroblasts, endothelial cell mitosis, promote collagen synthesis and secretion, thereby playing an anti-inflammatory, promoting granulation tissue growth, and accelerate wound healing. First, the role of ultraviolet light on the intercellular matrix Collagen is the main component of the extracellular matrix of skin tissue. In the process of wound repair, the body can transform the tissue after wound healing and healing through the synthesis, degradation and absorption of collagen, so that the tissue The repair was completed and improved. Fibronectin is involved in the wound repair process, and it accelerates wound repair by interacting with a variety of cells and extracellular matrices.