Fig. 4
MANF protects against Aβ1–42-induced cell toxicity. a MANF level in N2a cells transfected with MANF-Flag plasmid or MANF-siRNA. b MANF overexpression increases the cell viability in Aβ1–42-treated cells compared with that of pcDNA3.1-vector transfected cells. N2a cells were transfected with pcDNA3.1-vector or MANF-Flag plasmid. Twenty-four hours after transfection, the cells were treated with Aβ1–42 (10 μM) for indicated times and processed for the MTT assay. *P < 0.05, compared to vector-transfected cells at corresponding time points. c Effect of endogenous MANF knockdown on the vulnerability to Aβ1–42 (10 μM) cytotoxicity in N2a cells. N2a cells were transfected with NC-siRNA or effective MANF-siRNA. Twenty-four hours after transfection, the cells were treated with Aβ1–42 (10 μM) for indicated times and processed for the MTT assay. *P < 0.05, compared to NC-siRNA-transfected cells at according time points. d Effect of MANF on cell apoptosis induced by Aβ1–42. N2a cells were transiently transfected with MANF-Flag or MANF-siRNA followed by treatment of Aβ1–42 (10 μM) for another 24 h. TUNEL staining to determine the apoptotic cells. The nuclei were stained with DAPI. Scale bar = 100 μm. e Quantitative analysis of the number of TUNEL-positive cells in d. The TUNEL-positive cells were counted in five randomly selected fields from four sections of each group. *P < 0.05, **P < 0.01. f The protein levels of CHOP and cleaved caspase-3 were determined in Aβ1–42-treated N2a cells transfected with MANF-Flag or MANF-siRNA. GAPDH was used as a loading control. All the quantitative data were expressed as mean ± SD from three independent experiments