Activation of Adenosine A3 Receptor Alleviates TNF-α-Induced Inflammation through Inhibition of the NF-κB Signaling Pathway in Human Colonic Epithelial Cells
Figure 6
Effect of 2-Cl-IB-MECA on TNF-α-induced proinflammatory cytokine IL-8 and IL-1β expression in HT-29 cells. The cells were treated with various concentrations (10 nM, 30 nM, and 50 nM) of 2-Cl-IB-MECA for 30 min before TNF-α (10 ng/mL) stimulation and then incubated for 6 h in order to assay for mRNA expression by qRT-PCR or 24 h for measurement of protein secretion by ELISA. (a, b) The IL-8 and IL-1β mRNA were expressed at relatively low levels in the NC group. TNF-α treatment resulted in an increase in IL-8 and IL-1β mRNA expression. However, 2-Cl-IB-MECA significantly reduced the TNF-α-induced IL-8 and IL-1β mRNA expression in HT-29 cells in concentration-dependent manner. (c, d) In accordance with the alteration of mRNA, the TNF-α-treated group also had increased secretion of IL-8 and IL-1β proteins. Treatment with 2-Cl-IB-MECA significantly inhibited TNF-α-induced secretion of IL-8 and IL-1β protein in a concentration-dependent manner. Data are shown as the mean ± SD from three independent experiments. compared with the NC group; compared with the TNF-α-only-treated group; between indicated groups.
