Fig. 4

ER stress in epithelial cell lines is decreased by Naltrexone. a ER stress was induced in HCT116 cells by treatment with 2 μM Tunicamycin (Tuni), resulting in an upregulation of GRP78 expression levels as detected by Western Blot analysis. Co-treatment of cells with 1 μg/mL Naltrexone (NTX) reduces the amount of Tunicamycin-induced GRP78 expression. Upper graph: mean densitometry values of two independent experiments, GRP78 expression is corrected for Actin, to control for equal loading. Representative example is shown in the bottom panels. b Treatment of HCT116 cells with bacteria results in a significant upregulation of GRP78 expression as detected by Western blot analysis, which is reduced by co-treatment cells by treatment of cells with 1 μg/mL Naltrexone. Mean densitometry values of four independent experiments is shown. c Treatment of HCT116 cells with LPS results in a significant upregulation of CHOP expression as detected by Western blot analysis, which is reduced by co-treatment cells by treatment of cells with 1 μg/mL Naltrexone. Mean densitometry values of three independent experiments is shown. d Treatment of organoids with LPS results in a significant upregulation of GRP78 expression as detected by Western blot analysis, which is reduced by co-treatment cells by treatment of cells with 1 μg/mL Naltrexone. Mean densitometry values are shown of experiments performed on organoids derived from two individual donors, with two independent experiments each