Fig. 8.

N-acetylcysteine (NAC) significantly inhibits alcohol-induced expression of CLOCK and PER2 circadian proteins in Caco-2 intestinal cells. Caco-2 human intestinal cells were grown to confluence on Transwell inserts and stimulated with alcohol (EtOH, 0.2%, 43 mM) for 4 h. Cell lysates were then used to measure CLOCK and PER2 protein expression with Western blotting (30 μg protein/lane). Blots were stripped and reprobed with antibody to β-actin to validate equal lane loading. Blots shown are representative of N = 6 experiments (from 1 experiment), and histogram data are means ± SE for summarized data from all N = 6 experiments. *P < 0.05 vs. control; +P < .05 vs. 0.2% EtOH alone.