title: Blockade of hypoxia-inducible factor-1α by YC-1 attenuates interferon-γ and tumor necrosis factor-α-induced intestinal epithelial barrier dysfunction.
abstract: Proinflammatory cytokines play vital roles in intestinal barrier function disruption. YC-1 has been reported to have potent anti-inflammatory properties, and to be a potential agent for sepsis treatment. Here, we investigated the protective effect of YC-1 against intestinal barrier dysfunction caused by interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). To assess the protective effect of YC-1 on intestinal barrier function, Caco-2 monolayers treated with simultaneous IFN-γ and TNF-α were used to measure transepithelial electrical resistance (TER) and paracellular permeability. To determine the mechanisms involved in the protective action of YC-1, expression and distribution of tight junction proteins ZO-1 and occludin in Caco-2 monolayers challenged with simultaneous IFN-γ and TNF-α were analyzed by Western blot and immunofluorescence, respectively. Expressions of phosphorylated myosin light chain (MLC), MLC kinase (MLCK) and hypoxia-inducible factor-1α (HIF-1α) were analyzed by Western blot in IFN-γ and TNF-α-treated Caco-2 monolayers. It was found that YC-1 attenuated barrier dysfunction caused by IFN-γ and TNF-α, and also prevented IFN-γ and TNF-α-induced morphological redistribution of tight junction proteins ZO-1 and occludin in Caco-2 monolayers. In addition, YC-1 suppressed IFN-γ and TNF-α-induced upregulation of MLC phosphorylation and MLCK protein expression. Furthermore, enhanced expression of HIF-1α in Caco-2 monolayers treated with IFN-γ and TNF-α was also suppressed by YC-1. It is suggested that YC-1, by downregulating MLCK expression, attenuates intestinal barrier dysfunction induced by IFN-γ and TNF-α, in which HIF-1α inhibition, at least in part, might by involved. YC-1 may be a potential agent for treatment of intestinal barrier disruption in inflammation.
authors: State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors: Hang
authors: H
authors: Liu
authors: Mu
authors: M
authors: Li
authors: Pei
authors: P
authors: Wang
authors: Fengjun
authors: F
authors: Wang
mesh_terms: D018938:Caco-2 Cells; D004848:Epithelium / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007191:Indazoles / Q000494:pharmacology*; D007371:Interferon-gamma / Q000494:pharmacology*; D007422:Intestines / Q000473:pathology*; D008565:Membrane Proteins / Q000378:metabolism; D018994:Myosin Light Chains / Q000378:metabolism; D009219:Myosin-Light-Chain Kinase / Q000378:metabolism; D062793:Occludin; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects; D062826:Zonula Occludens-1 Protein
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007191:Indazoles; D008565:Membrane Proteins; D018994:Myosin Light Chains; C568985:OCLN protein, human; D062793:Occludin; D010750:Phosphoproteins; C569042:TJP1 protein, human; D014409:Tumor Necrosis Factor-alpha; D062826:Zonula Occludens-1 Protein; C090937:3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole; D007371:Interferon-gamma; D009219:Myosin-Light-Chain Kinase