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Updated: May 16, 2026

Determining the Toxicity of UV Radiation and Chemicals on Primary and Immortalized Human Corneal Epithelial Cells
Published on: July 22, 2021
Protective effect of pyruvate against UVB-induced damage in HaCaT human keratinocytes
Ayako Aoki-Yoshida1, Reiji Aoki, Yoshiharu Takayama
1The Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
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.
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