Figure 6. The C-Raf-ERK1/2 pathway was involved in the anti-apoptotic action of nesfatin-1 in MES23.5 cells.

(A,B) Nesfatin-1 (10⁻⁹ mol/L) stimulated phosphorylation of ERK1/2 after 2, 5, 10, 20, 30, and 60 min, with levels of phosphorylation peaking at 30 min. (C,D) Pretreatment with the ERK1/2 inhibitor PD98059 (10 μmol/L) abolished nesfatin-1-induced ERK1/2 phosphorylation. (E,F) Pretreatment with PD98059 (10 μmol/L) abolished the protective effect of nesfatin-1 (10⁻⁹ mol/L) on the collapse of the ΔΨm induced by MPP⁺. (G,H) Pretreatment with PD98059 (10 μmol/L) abolished the protective effect of nesfatin-1 (10⁻⁹ mol/L) on caspase-3 activation induced by MPP⁺. (I,J) Pretreatment with the C-Raf inhibitor GW5074 (5 μmol/L) abolished the protective efficacy of nesfatin-1 (10⁻⁹ mol/L) on the MPP⁺-induced collapse of the ΔΨm. (K,L) Pretreatment with GW5074 (5 μmol/L) abolished the protective effect of nesfatin-1 (10⁻⁹ mol/L) on caspase-3 activation induced by MPP⁺. ^*P < 0.05 compared with the control group. ^#P < 0.05 compared with the MPP⁺-treated group. Full-length blots are presented in Supplementary Figure S6. (MPP⁺:1-methyl-4-phenylpyridillium ion, ERK1/2: extracellular signal-regulated protein kinase 1/2, ΔΨm: mitochondrial transmembrane potential).