title: Real-time monitoring of trans-epithelial electrical resistance in cultured intestinal epithelial cells: the barrier protection of water-soluble dietary fiber.
abstract: OBJECTIVE
  In this study we aimed to verify a real-time trans-epithelial electrical resistance (TEER) monitoring system in a Caco-2 monolayer and to investigate the therapeutic effect of partially hydrolyzed guar gum (PHGG), a dietary fiber, against interferon (IFN)-γ-induced intestinal barrier dysfunction using this monitoring system.
  
  
  METHODS
  We measured TEER using a real-time monitoring system and evaluated epithelial paracellular permeability using fluorescein isothiocyanate-conjugated dextran (4 kDa; FD4) in Caco-2 monolayers treated with IFN-γ for 48 h. The expression and distribution of tight junction (TJ)-associated proteins, ZO-1 and occludin, were analyzed by Western blot and immunocytochemistry, respectively. In some experiments PHGG was added prior to IFN-γ treatment in order to investigate its protective effect on barrier function.
  
  
  RESULTS
  IFN-γ treatment significantly decreased TEER and increased FD4 flux across Caco-2 monolayers, indicating a great influence of IFN-γ on the intestinal epithelial paracellular permeability. In contrast, the pretreatment of PHGG significantly reduced the IFN-γ-induced increment of FD4 flux without affecting TEER. Neither IFN-γ nor PHGG treatment affected the expressions of TJ-associated proteins, while immunocytochemistry showed that IFN-γ-induced redistribution of occludin was clearly restored by PHGG.
  
  
  CONCLUSIONS
  Real-time TEER monitoring enabled us to evaluate the dynamic changes of intestinal epithelial barrier function. PHGG may have a protective effect against IFN-γ-induced barrier dysfunction by attenuating the paracellular hyperpermeability; thus, its promotion as a functional food is anticipated.
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Majima
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Handa
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Naito
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Suyama
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Onozawa
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Higashimura
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Katsura
authors.initials: K
authors.lastname: Mizushima
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Morita
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Uehara
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Horie
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Takaya
authors.initials: T
authors.lastname: Iida
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Akifumu
authors.initials: A
authors.lastname: Fukui
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Dohi
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Okayama
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kamada
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Katada
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Uchiyama
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Takagi
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Konishi
authors.affiliation: Nutrition Division, Taiyo Kagaku Co. Ltd, Yokkaichi, Japan.
authors.forename: Zenta
authors.initials: Z
authors.lastname: Yasukawa
authors.affiliation: Nutrition Division, Taiyo Kagaku Co. Ltd, Yokkaichi, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Tokunaga
authors.affiliation: Nutrition Division, Taiyo Kagaku Co. Ltd, Yokkaichi, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Okubo
authors.affiliation: Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Itoh
mesh_terms: D018938:Caco-2 Cells; D004043:Dietary Fiber / Q000494:pharmacology*; D017097:Electric Impedance; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005685:Galactans / Q000494:pharmacology; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007371:Interferon-gamma / Q000037:antagonists & inhibitors / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D008351:Mannans / Q000494:pharmacology; D010539:Permeability / Q000187:drug effects; D053149:Plant Gums / Q000494:pharmacology; D012995:Solubility; D062725:Tight Junction Proteins / Q000378:metabolism; D019108:Tight Junctions / Q000187:drug effects
chemical_list: D004043:Dietary Fiber; D005685:Galactans; D008351:Mannans; D053149:Plant Gums; D062725:Tight Junction Proteins; D007371:Interferon-gamma; D006861:Hydrogen Peroxide; C007894:guar gum
keywords: intestinal barrier function; occludin; paracellular permeability; partially hydrolyzed guar gum; trans-epithelial electrical resistance