Lactobacillus plantarum inhibits epithelial barrier dysfunction and interleukin-8 secretion induced by tumor necrosis factor-α

Figure 1 Effect of L. plantarum on transepithelial resistance. TNF-α decreased Caco-2 monolayer resistance. L. plantarum reversed TNF-α-induced decreases in transepithelial resistance. ^aP < 0.05, compared with TNF-α. TER: transepithelial electrical resistance; LP: L. plantarum; TNF, TNF-α.

Figure 2 Effect of L. plantarum on TNF-α-induced IL-8 secretion by Caco-2 cells. TNF-α-induced IL-8 secretion was significantly reduced by L. plantarum. ^aP < 0.05, compared with TNF-α. LP: L. plantarum; TNF, TNF-α.

Figure 3 Effect of L. plantarum on the ERK pathway. Caco-2 cells were incubated with L. plantarum, TNF-α or L. plantarum plus TNF-α. Cell lysates were immunoblotted with antibodies against phosphorylated ERK and total ERK. L. plantarum inhibited TNF-α-induced activation of ERK-1 and -2. LP: L. plantarum; TNF, TNF-α.

Figure 4 Effect of L. plantarum on IκB-α degradation. Caco-2 cells were incubated with L. plantarum, TNF-α or L. plantarum plus TNF-α. Cell lysates were immunoblotted with antibodies against IκB-α. TNF-α caused degradation of IκB-α. L. plantarum inhibited TNF-α-induced IκB-α degradation. LP: L. plantarum; TNF, TNF-α.