Roles of p38 and ERK signaling pathway in cell apoptosis induced by UVB irradiation

• Published in: Nan fang yi ke da xue xue bao = Journal of Southern Medical University Vol. 28; no. 7; p. 1145
• Main Authors: Zhou, Mei-juan, DU, Hua, Ding, Zhen-hua
• Format: Journal Article
• Language: Chinese
• Published: China 01.07.2008
• Subjects: Apoptosis - radiation effects; Cells, Cultured; Extracellular Signal-Regulated MAP Kinases - metabolism; Humans; Keratinocytes - cytology; Keratinocytes - metabolism; Keratinocytes - radiation effects; p38 Mitogen-Activated Protein Kinases - metabolism; Signal Transduction - radiation effects; Ultraviolet Rays
• ISSN: 1673-4254

To explore the involvement of p38 and ERK signal transduction pathways in UVB-induced cell apoptosis. HaCat cells were exposed to UVB irradiation for 1, 3, 5, 10, and 15 min, respectively, after which the cell survival was assessed using MTT assay, and the cell apoptosis observed under fluorescent microscope with Hoechst staining. Western blotting was used to examine the possible signal transduction pathway involved in the cell apoptosis following the exposures. For the same incubation time following the exposure, the cell survival rate decreased gradually with the increase of UVB irradiation dose. At a fixed UVB irradiation dose, prolonged cell incubation following the exposure resulted in decreased cell survival rate, which, however, began to increase after the minimum rate was reached. At different UVB doses, cell exposure for 5 min caused the highest cell apoptosis rate, which peaked at 12 h during the post-irradiation incubation. The expressions of p38 and p53 were significantly decreased while p44/42 ex