title: Critical role of Keratin 1 in maintaining epithelial barrier and correlation of its down-regulation with the progression of inflammatory bowel disease.
abstract: Inflammatory bowel disease (IBD) is the result of a chronic intestinal inflammatory response which usually occurred in colon and small intestine. Keratins constitute the intermediate filament cytoskeleton in all epithelia. The present study was intended to explore the role of Keratin 1 (KRT1) in the progress of IBD. In normal intestinal tissue, the expression of KRT1 was detected by RT-PCR and Western blot. The levels of KRT1 protein significantly decreased in serum samples of IBD patients as compared with sera of healthy controls. Immunohistochemistry revealed that the expression of KRT1 decreased in various intestinal diseases, especially in Crohn's disease and ulcerative colitis. Furthermore, down-regulated KRT1 was correlated with the severity of IBD. The overexpression of KRT1 maintained epithelial barrier in Caco-2 cells after IL-1β treatment. Furthermore, IL-1β-induced disruption of tight junction became significantly attenuated in KRT1 over-expressing Caco-2 cells as compared with control cells. Thus, KRT1 played an important role of maintaining epithelial barrier and its down-regulation in intestinal tissue was correlated with the progression of IBD.
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Xiangqian
authors.initials: X
authors.lastname: Dong
authors.affiliation: Kunming Key Laboratory of Hydroecology Restoration of Dianchi Lake, Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province, Department of Biological Science and Technology, Kunming University, Kunming 650214, China.
authors.forename: Zichao
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Danfeng
authors.initials: D
authors.lastname: Lan
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Junkun
authors.initials: J
authors.lastname: Niu
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Jiarong
authors.initials: J
authors.lastname: Miao
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Fengrui
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Disease, Kunming 650032, China.
authors.forename: Kunhua
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Kunming Medical University, Yunnan Institute of Digestive Diseases, Kunming 650032, China. Electronic address: myldu@sina.com.
authors.forename: Yinglei
authors.initials: Y
authors.lastname: Miao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018938:Caco-2 Cells; D016022:Case-Control Studies; D002478:Cells, Cultured; D002648:Child; D018450:Disease Progression; D015536:Down-Regulation; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000235:genetics* / Q000473:pathology*; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology*; D053556:Keratin-1 / Q000235:genetics / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D019108:Tight Junctions / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
chemical_list: C491616:KRT1 protein, human; D053556:Keratin-1
keywords: Cytoskeleton; Epithelial barrier; Inflammatory bowel disease; Keratin; Tight junction