Cells treated with insulin (200 nM) were used as controls. The insulin- and CHM-treated cells were then incubated with an H2O2 (300 μM) solution. Western blot analysis was performed by staining membranes with anti-phospho-p38 MAPK, anti-p38 MAPK, anti-phospho-p44/42 MAPK, anti-p44/42 MAPK, and anti-GAPDH antibodies. (A) Western blot analysis of phospho-p38 MAPK, p38 MAPK, phospho-p44/42 MAPK, p44/42 MAPK, and GAPDH protein expression. (B) The ratio of phospho-p38 MAPK to p38 MAPK in various treatment groups versus that in untreated cells. *P < 0.05. (C) The ratio of phospho-p44/42 MAPKs to p44/42 MAPKs in various treatment groups versus that in untreated cells. *P < 0.05.