Fig. 3.

Knockdown of PP2A-Cα dampens acetaldehyde-induced barrier dysfunction and tight junction disruption. A: Caco-2 cells were transfected with siRNA specific for catalytic subunit of PP2A or nonspecific RNA (NS-RNA). Protein extracts were immunoblotted for PP2A-C and PP1. The graph shows the densitometric analysis of PP2A bands. Values are means ± SE (n = 4). *Significantly different (P < 0.05) from the value for NS-RNA. B: inulin flux was measured after 5 h of exposure to acetaldehyde (300 or 400 μM). Values are means ± SE (n = 4). *Significantly different from control values. #Significantly (P < 0.05) different from corresponding values for NS-RNA group. C: after incubation with varying amounts of acetaldehyde for 5 h the cell monolayers were fixed and stained for occludin (green) or ZO-1 (red).