Keratinocytes effects

Gonzalez, M.C., C. Marteau, J. Franchi, and D. Migliore-Samour (2001). Cytochrome P450 4A11 expression in human keratinocytes Effects of ultraviolet irradiation. Br. J. Dermatol. 145, 749-757. 

Fig. 14 Effect of the molecular weight of tamarind seed xyloglucan depolymerized by ( ) 7-irradiation, ( ) ultrasonication, and ( ) endo-glucanase treatment on the production of various cytokines (Tumor necrosis factor a, TNE-a Interleukin 8, IL-8 Interleukin 10, IL-10 and Interleukin 12, IL-12) in HaCaT cells (Immortalized keratinocytes line) [301]...

Salicylic acid has a keratolytic effect, thus eliminating superficial pigmented keratinocytes and stimulating cells turnover. This superficial peeling allows TCA to act a low concentration to remove pigmented keratinocytes through papillary dermis (see Fig. 14.12). 

Punnonen, K., Jansen, C.T., Puntala, A. and Ahotupa. M. (1991b). Effects of in vitro UVA irradiation and PUVA treatment on membrane fatty acids and activities of anti-oxidant enzymes in human keratinocytes. J. Invest. Dermatol. 96, 255-259. 

In 1986, the antioxidant effects of thioredoxin reductase were studied by Schallreuter et al. [81]. It has been shown that thioredoxin reductase was contained in the plasma membrane surface of human keratinocytes where it provided skin protection against free radical mediated damage. Later on, the reductive activity of Trx/thioredoxin reductase system has been shown for the reduction of ascorbyl radical to ascorbate [82], the redox regulation of NFkB factor [83], and in the regulation of nitric oxide-nitric oxide synthase activities [84,85],... 

Vitamin D and its analogs inhibit keratinocyte differentiation and proliferation and have antiinflammatory effects by reducing IL-8, IL-2, and other cytokines. Use of vitamin D itself is limited by its propensity to cause hypercalcemia. 

Tazarotene (Tazorac) is a synthetic retinoid that is hydrolyzed to its active metabolite, tazarotenic acid, which modulates keratinocyte proliferation and differentiation. It is available as a 0.05% or 0.1% gel and cream and is applied once daily (usually in the evening) for mild to moderate plaque psoriasis. Adverse effects are dose- and frequency related and include mild to moderate pruritus, burning, stinging, and erythema. Application of the gel to eczematous skin or to more than 20% of body surface area is not recommended because this may lead to extensive systemic absorption. Tazarotene is often used with topical corticosteroids to decrease local adverse effects and increase efficacy. 

Chen, P. H. et al., Effects of arsenic and UVB on normal human cultured keratinocytes Impact on apoptosis and implication on photocarcinogenesis, Chem. Res. Toxicol., 18, 139, 2005. 

Albanesi, C., Cavani, A., and Girolomoni, G., IL-17 is produced by nickel-specific T lymphocytes and regulates ICAM-1 expression and chemokine production in human keratinocytes synergistic or antagonistic effects with IFN-y and TNF-a. J. Immunol. 162, 494-502, 1999. 

Xiao L, Takada H, Maeda K, Haramoto M, Miwa N (2005) Antioxidant effects of water-soluble fullerene derivatives against ultraviolet ray or peroxylipid through their action of scavenging the reactive oxygen species in human skin keratinocytes. Biomed. Pharmacother. 59 351-358. 

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