Fig. 3

Nrf2 is required for UroA/UAS03 mediated upregulation of tight junction proteins. a Nrf2 levels were determined by immunoblots in HT29 cells treated with vehicle/UroA/UAS03 (50 μM) for 24 h. b Nrf2 expression in cytosolic and nuclear fractions of HT29 cells treated with Veh/UroA/UAS03 (50 μM) for 6 h. c Immunofluorescence confocal images of HT29 cells treated with vehicle/UroA/UAS03 (50 μM) for 6 h. The cells were stained with anti-Nrf2 antibody and DAPI. Relative green fluorescence (n = ~20 cells) intensity was measured. Scale bars indicate 25 μm. d Expression of Cldn4 and NQO1 in colon explants from WT, Nrf2^−/−, and AhR^−/− mice treated with vehicle/UroA/UAS03 (50 μM) for 24 h. Immunoblots were quantified using Image J software. e mRNA levels of Cldn4, Nrf2, and HO1 from colon explant cultures was measured by real-time PCR using SyBr green method. f C57BL/6, Nrf2^−/−, and AhR^−/− mice (n = 3) treated orally daily with veh or UroA/UAS03 (20 mg/kg) for 1 week. Cldn4 and NQO1 protein levels in colons were measured by immunoblots and quantified by Image J software. All in vitro studies were performed in triplicates. The immunoblots of colon explants and colon tissues were quantified from at least 6 independent runs. The levels of proteins were normalized to β-actin and Wild type vehicle treatment was set to 1 and calculated the fold changes. Statistics performed using unpaired t-test using Graphpad Prism software. Error bars, ±SEM; *p < 0.05; **p < 0.01; ***p < 0.001. Source Data are provided as a Source Data File