Fig. 6: Factors regulating neuronal survival and APP mRNA transcription induced by NF-α1/CPE.

A Serpina3g protects HT22 hippocampal neurons against H₂O₂-induced cytotoxicity. Bar graphs (stippled bars) showing that cell cytotoxicity decreased in HT22 cells expressing serpina3g compared to cells expressing vector alone. Open bars showing cytotoxicity level (made = 1) in the control cells expressing serpina3g or vector, but not treated with H₂O₂. Values shown are the mean ± SEM, p < 0.05, t-test, N = 3. B Reduction of APP mRNA levels in 3xTg-AD mice and cells after NF-α1/CPE gene delivery. Left panel: Bar graphs showing relative human and mouse APP mRNA levels in 3xTg-AD mouse hippocampus after delivery of AAV-NF-α1/CPE or AAV-GFP. Values shown are the mean ± SD, n = 2 mice per genotype. Middle panel: HT22^cpe−/− cells were transiently transfected with CPE or vector for 48 h and then harvested for qRT- PCR assay. Bar graphs showing relative mAPP mRNA level. Values shown are the mean ± SEM, N = 3. Right panel: HEK293 cells were transiently transfected with CPE and vector for 48 h and then harvested for qRT- PCR assay. Bar graphs showing relative hAPP mRNA level. Values shown are the mean ± SEM, N = 3. C. Reduction of transcription factor mRNAs in HT22^cpe−/− cells after CPE transfection. HT22^cpe−/− cells were transiently transfected with CPE or vector for 48 h and then harvested for qRT- PCR assay. Bar graphs showing relative mRNA levels of 4 transcription factors were reduced with CPE transfection. Values shown are the mean ± SEM, N = 3. *p < 0.05, **p < 0.01, ***p < 0.001. D Schematic showing hippocampal injection of AAV- NF-α1/CPE in 3xTg-AD mice down-regulates expression of APP in pyramidal neurons via attenuating transcription factors Sp1 and Hsf-1 expression. These transcription factors bind to the promoter of APP gene to promote transcription. Red arrows indicate APP positive neurons.