title: Protective effect of pyruvate against UVB-induced damage in HaCaT human keratinocytes.
abstract: The protective effect of pyruvate against ultraviolet B (UVB)-induced damage was investigated in human immortalized keratinocytes (HaCaT cells). Although pyruvate did not inhibit UVB-induced stimulation of intracellular reactive oxygen species (ROS) levels, it did improve the survival rate of UVB-irradiated HaCaT cells. Furthermore, pyruvate suppressed the UVB-induced mRNA expression of inflammatory mediators such as interleukin (IL)-1α, IL-1β, IL-6 and cyclooxygenase-2 (Cox-2). This decrease was associated with the reduced secretion of IL-1α, IL-1β, IL-6 and prostaglandin E2 (PGE2) into culture media. In addition, pyruvate reversed the phosphorylation of p38 mitogen-activated protein kinase (MAPK), induced by UVB-irradiation, in HaCaT cells but increased p38 MAPK phosphorylation in sham-irradiated cells. UVB-induced production of IL-6 was inhibited by SB203580, a p38 MAPK inhibitor. These results suggested that pyruvate inhibits UVB-mediated inflammatory response by inhibiting the p38 MAPK activation.
authors.affiliation: The Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Aoki-Yoshida
authors.forename: Reiji
authors.initials: R
authors.lastname: Aoki
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Takayama
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D010766:Phosphorylation / Q000187:drug effects / Q000528:radiation effects; D019289:Pyruvic Acid / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D018836:Inflammation Mediators; D007375:Interleukin-1; D015850:Interleukin-6; D017382:Reactive Oxygen Species; D019289:Pyruvic Acid; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone