Activation of ERK1/2 by protein kinase C-alpha in response to hydrogen peroxide-induced cell death in human gingival fibroblasts

作者：Gutierrez Venegas Gloria^*; Antonio Arreguin Cano Juan; Arroyo Cruz Rita; Villeda Navarro Monica; Antonio Mendez Mejia Jose

来源：Toxicology in Vitro, 2010, 24(1): 319-326.

DOI：10.1016/j.tiv.2009.08.007

• Hydrogen peroxide
• Human gingival fibroblasts
• Mitogen-activated kinases

Hydrogen peroxide (H(2)O(2)) increases protein tyrosine phosphorylation of numerous proteins in human gingival fibroblasts (HGFs). Two main proteins, with an apparent molecular weight of 44 and 42 kDa, were phosphorylated after hydrogen peroxide stimulation of the human gingival fibroblasts. Further analysis identified these two proteins as ERK1/2. Maximum phosphorylation was detected at 10 min post-H(2)O(2) treatment. Pretreatment with an MEK inhibitor, PD98059, inhibited H(2)O(2)-stimulated ERK1/2 phosphorylation in a dose-dependent manner. Treatment with H(2)O(2) also induced phosphorylation of protein kinase C-alpha (PKC alpha). Staurosporine, a PKC inhibitor, blocked ERK1/2 phosphorylation induced by H(2)O(2). In addition, H(2)O(2)-induced cell death was prevented by PD98059, SB203580, and calphostin C, which are MEK, p38 and PKC inhibitors, respectively. These results suggest that H(2)O(2) leads to the phosphorylation and activation of ERK1/2 in a PKC-dependent manner. These findings demonstrate that the MAPK signaling pathway plays an active role in mediating the H(2)O(2)-induced decrease in HGF cell viability and ATP depletion.

• 出版日期2010-2