title: Baicalin Protects against TNF-α-Induced Injury by Down-Regulating miR-191a That Targets the Tight Junction Protein ZO-1 in IEC-6 Cells.
abstract: Tumor necrosis factor-alpha (TNF-α) plays an important role in the developing process of inflammatory bowel disease. Tight junction protein zonula occludens-1 (ZO-1), one of epithelial junctional proteins, maintains the permeability of intestinal barrier. The objective of this study was to investigate the mechanism of the protective effect of baicalin on TNF-α-induced injury and ZO-1 expression in intestinal epithelial cells (IECs). We found that baicalin pretreatment significantly improved cell viability and cell migration following TNF-α stimulation. miR-191a inhibitor increased the protective effect of baicalin on cell motility injured by TNF-α. In addition, miR-191a down-regulated the mRNA and protein level of its target gene ZO-1. TNF-α stimulation increased miR-191a expression, leading to the decline of ZO-1 mRNA and protein. Moreover, pretreatment with baicalin reversed TNF-α induced decrease of ZO-1 and increase of miR-191a, miR-191a inhibitor significantly enhanced ZO-1 protein expression restored by baicalin. These results indicate that baicalin exerts a protective effect on IEC-6 (rat small intestinal epithelial cells) cells against TNF-α-induced injury, which is at least partly via inhibiting the expression of miR-191a, thus increasing ZO-1 mRNA and protein levels.
authors.affiliation: School of Basic Medical Sciences, Guangzhou University of Chinese Medicine.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Ren
authors.initials: R
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.forename: Qihui
authors.initials: Q
authors.lastname: Wu
authors.forename: Zaoyuan
authors.initials: Z
authors.lastname: Kuang
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010539:Permeability / Q000187:drug effects; D020011:Protective Agents / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D031364:Scutellaria baicalensis / Q000737:chemistry; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D062826:Zonula Occludens-1 Protein / Q000235:genetics* / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D035683:MicroRNAs; D020011:Protective Agents; D012333:RNA, Messenger; C569044:Tjp1 protein, rat; D014409:Tumor Necrosis Factor-alpha; D062826:Zonula Occludens-1 Protein; C038044:baicalin