[Activation of nuclear factor-kappa B and expression of cytokine in intestinal epithelia stimulated by TNF-alpha]

Abstract

Objective: To investigate the effect of nuclear factor-kappa B activation on proinflammatory cytokine expression in intestinal epithelia when intestinal epithelia are in inflammatory condition.

Methods: Colonic adenocarcinoma HT29 cells were cultured in wells and TNF-alpha (10 ng/ml) was added into half of the wells. The supernatants were collected and measured for IL-8 after 3 hours, nuclear factor-kappaB (NF-kappaB) P65 and IL-8 mRNA were also examined by Western blotting and RT-PCR respectively.

Results: It was found that in the condition of no stimuli, there is little IL-8 mRNA expression of HT29 cells, P65 is seldom in HT29 cells' nuclei, and the concentration of IL-8 in supernatant is just 172 ng/L. However, after being stimulated by TNF-alpha, a lot of P65 expression in nuclei and a large number of IL-8 mRNA expression of HT29 cells are shown and the concentration of IL-8 in supernatant (639 ng/L) is significantly higher than that of control (P<0.01).

Conclusion: The activation of nuclear factor-kappa B modulates the expression of some proinflammatory cytokine in intestinal epithelia, and regulates epithelia function in inflammatory reaction.