Interleukin-1β regulates CFTR expression in human intestinal T84 cells

Abstract

Cystic fibrosis is an autosomal recessive genetic disease, produced by a mutation in the CFTR gene that impairs its function as a chloride channel. In this work, we have examined the effects of interleukin-1beta (IL-1beta) on the expression of CFTR in human colonic T84 cells. Treatment of T84 cells with IL-1beta (0.25 ng/ml) for 4 h resulted in an increased CFTR expression (mRNA and protein). However, higher doses of IL-1beta (1 ng/ml and over) produced inhibition of CFTR mRNA and protein expression. The protein kinase C (PKC) inhibitors H7 (50 microM) and GF109203X (1 microM) inhibited the stimulatory effect of IL-1beta. Similar effects were seen in the presence of the protein tyrosine kinase (PTK) inhibitors genistein (60 microM) and herbymicin A (2 microM). These results suggest that some PKC isoform(s) and at least a PTK might be involved in the CFTR up-regulation induced by IL-1beta. The repression of CFTR up-regulation by cycloheximide (35.5 microM) suggests the participation of a de novo synthesized protein. Results obtained by using the RNA polymerase II inhibitor DRB (78 microM), suggest that the increased mRNA levels seen after IL-1beta treatment are not due to an increased stability of the message. We conclude that the CFTR mRNA and protein levels are modulated by IL-1beta, this cytokine being the first extracellular protein known to up-regulate CFTR gene expression.

MUC4 expression is regulated by cystic fibrosis transmembrane conductance regulator in pancreatic adenocarcinoma cells via transcriptional and post-translational mechanisms

“…In another report, interferon-gamma, a pro-inflammatory cytokine was shown to downregulate CFTR expression in colonic T84 cells, while activating EGFR in a Src kinase dependent manner (Uribe et al, 2002). Studies have also suggested the role of interleukin-1 beta (IL1-b) in regulating the expression of CFTR via a mechanism that involves NF-kB activation (Cafferata et al, 2000(Cafferata et al, , 2001. Altogether, these studies suggest that altered cell signalling and microenvironment changes in cancer condition may be implicated in the downregulation of CFTR expression in pancreatic cancer.…”

Post-Transcriptional Regulation of Cystic Fibrosis Transmembrane Conductance Regulator Expression and Function by MicroRNAs

“…The TNF-a-mediated and IL-1b-mediated regulation of CFTR expression was addressed in previous studies (30)(31)(32)(33)(34)(35)(36)(37). TNF-a was reported to decrease CFTR expression (33) and reduce CFTR mRNA stability via the influence of mitogen-activated protein kinase cascades (30,33), and may be more effective in reducing CFTR mRNA concentrations in combination with IFN-g (35).…”

“…TNF-a was reported to decrease CFTR expression (33) and reduce CFTR mRNA stability via the influence of mitogen-activated protein kinase cascades (30,33), and may be more effective in reducing CFTR mRNA concentrations in combination with IFN-g (35). IL-1b, on the other hand, exhibits a biphasic effect on CFTR expression (31,37). Concentrations greater than 1 to 10 ng/ml decrease CFTR expression, whereas concentrations below 1 ng/ml exert the opposite effect.…”

“…Previous studies suggested a role for proinflammatory cytokines in the regulation of CFTR expression (30)(31)(32)(33)(34)(35)(36)(37). To test the possibility that the TNF-a-mediated or IL-1b-mediated increases in miR-509-3p and miR-494 expression influence CFTR abundance, we measured CFTR expression in well-differentiated primary cultures of human non-CF airway epithelia and polarized ALI cultures of Calu-3 airway epithelia after TNF-a or IL1b treatment.…”

Spermidine Stimulates T Cell Protein-tyrosine Phosphatase-mediated Protection of Intestinal Epithelial Barrier Function

“…Therefore, in an effort to further elucidate the mechanism by which spermidine increased TCPTP protein levels, the ribosomal inhibitor cycloheximide was used to investigate whether spermidine induced TCPTP protein synthesis. Previous studies employing the T 84 cell line used cycloheximide at a final concentration of 35.5 M to effectively inhibit protein synthesis (17). Therefore, T 84 cells grown as monolayers on permeable supports were treated with cycloheximide (35.5 M) for 30 min followed by the addition of spermidine (10 M) for 24 h. Western blotting indicated a 19 Ϯ 6% decrease in TCPTP protein levels in T 84 cells incubated with cycloheximide compared with the dimethyl sulfoxide vehicle control (p Ͻ 0.05, Fig.…”