PEITC activates leptin signaling in differentiated SH-SY5Y cells.

(A) Effects of PEITC treatment on cell viability in the differentiated SH-SY5Y cells. After the SH-SY5Y cells were incubated with the indicated concentration of PEITC in serum-free DMEM for 24 h, the cell viability was measured. The results are shown as means ± S.E.M. (n = 4). N.S. not significant (ANOVA, Dunnett’s multiple comparison test). (B) Concentration-dependent inhibition of cellular PTP1B by PEITC treatment in the differentiated SH-SY5Y cells. Cellular PTP1B activity was measured in the SH-SY5Y cells after treatment with the indicated concentrations of PEITC or 200 μM Na3VO4 in serum-free DMEM for 30 min. The results shown are means ± S.E.M. (n = 6). **p vs vehicle-treated control (ANOVA, Dunnett’s multiple comparison test). (C–G) Activation of leptin signaling in the differentiated SH-SY5Y cells by PEITC treatment. The SH-SY5Y cells were treated with the indicated concentrations of PEITC for 30 min (C–F) in serum-free DMEM. Then, the levels of p-Ob-Rb, p-JAK2, p-STAT3, PTP1B, and GAPDH were determined by immunoblotting. (D–F) The levels of p-Ob-Rb (D), p-JAK2 (E), p-STAT3 (F) were normalized for GAPDH. Data are the mean ± S.E.M. of three independent immunoblots (Fig 3C and S5A Fig). *p p vs vehicle-treated control (Student’s t-test). (G) Time course of activation of leptin signaling in the differentiated SH-SY5Y cells by PEITC treatment. The SH-SY5Y cells were treated with the indicated concentrations of 1 μM PEITC for 0–180 min in serum-free DMEM. Then, the levels of p-Ob-Rb, p-JAK2, p-STAT3, PTP1B, and GAPDH were determined by immunoblotting. Data are representative of two independent experiments.