Fig. 5. PON2 reduces the IGF-1 level via C-Jun transcription factor in ID8 cells.

ID8^EV and ID8^hPON2 cell culture lysates were prepared and utilized for chromatin immunoprecipitation assays with C-Jun (a) and p53 (b) antibodies. c) Equal number of ID8^hPON2 cells were plated in six-well plates. At 60 % confluence level, ID8^hPON2 cells were transfected with either hPON2 siRNA or scrambled siRNA, and PON2 expression analyzed by western blotting. d) Data in c are quantified using ImageJ software. e) Four six-well plates of cells were pooled from PON2-siRNA-treated ID8^hPON2 or scrambled siRNA-treated ID8^hPON2 cells. Chromatin immunoprecipitation assay was performed and C-Jun promoter was quantified (e) as described in the materials and methods section. Cell culture supernatants obtained from cells described under (e) and IGF-1 level was analyzed by ELISA (f), g) cell proliferation, and h) mitochondrial superoxide levels were measured as described in the method section. *p < 0.05, compared to ID8^EV. Values were expressed as fold changes (n = 3)