PDI
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Perit Dial Int 29(2): 217-226
2009
© 2009 International Society for Peritoneal Dialysis
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Horiuchi, T.
Right arrow Articles by Ohta, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Horiuchi, T.
Right arrow Articles by Ohta, Y.

Bench

HPMCs INDUCE GREATER INTERCELLULAR DELOCALIZATION OF TIGHT JUNCTION-ASSOCIATED PROTEINS DUE TO A HIGHER SUSCEPTIBILITY TO H2O2 COMPARED WITH HUVECs

Takashi Horiuchi1, Kazuya Matsunaga1, Masatoshi Banno1, Yusuke Nakano1, Kohei Nishimura1, Chika Hanzawa1, Kei-ichi Miyamoto1, Shinsuke Nomura2 and Yuji Ohta3

Division of Chemistry for Materials,1 Faculty of Engineering, Graduate School of Mie University; Division of Therapeutic Blood Purification,2 Mie University School of Medicine, Ochanomizu University,3 Tsu, Mie, Japan

Correspondence to: T. Horiuchi, Division of Chemistry for Materials, Faculty of Engineering, Graduate School of Mie University, 1577 Kurima-Machiyacho, Tsu, Mie, 514-8507 Japan. horiuchi{at}chem.mie-u.ac.jp

{diamondsuit} Background: Reactive oxygen species (ROS) have been speculated as possible inducers of structural or functional changes that lead to a hyperpermeable state in patients on long-term peritoneal dialysis. This study aimed to compare localization of tight junction-associated proteins (TJPs), which relate to solute permeability characteristics, between human peritoneal mesothelial cell (HPMC) monolayers and human umbilical vein endothelial cell (HUVEC) monolayers under oxidative stress.

{diamondsuit} Methods: HPMCs and HUVECs were cultured on a polymer mesh until transepithelial electrical resistance reached a plateau. Solute permeation tests were conducted using FITC-labeled dextrans. Localization of TJPs was observed under a confocal laser scanning microscope. These experiments were carried out with/without 0.1 mmol/L H2O2. In addition, ROS production as well as the amounts of intracellular reductive glutathione (GSH) and oxidative glutathione were measured.

{diamondsuit} Results: When the monolayers were exposed to 0.1 mmol/L H2O2/medium for 2 hours, the HPMC monolayer revealed a significant reduction in transepithelial electrical resistance (from 32.5 ± 3.4 to 17.4 ± 4.9 {Omega}·cm2) with delocalization of TJPs, particularly occludins. The HUVEC monolayer remained stable and exhibited an unremarkable change in TJP organization. Compared to the HUVEC monolayer, the HPMC monolayer exhibited two- to threefold higher 2',7'-dichlorofluorescein intensities that increased in a dose-dependent manner. HUVECs contained approximately 2.5-times more GSH than HPMCs. This supported the lesser production of ROS when exposed to 0.1 mmol/L H2O2 for 24 hours. HUVECs used 8.03 nmol/mg GSH protein to maintain TJP localization, while only 3.75 nmol/mg GSH protein was available for the HPMCs.

{diamondsuit} Conclusion: The HUVEC monolayer, which was less permeable to middle-to-high molecular weight solutes, was more tolerant against ROS stress than the HPMC monolayer. Availability of intracellular GSH is an important issue in maintaining the integrity of the mesothelium.

KEY WORDS: Human peritoneal mesothelial cells; human umbilical vein endothelial cells; solute permeability; occludin; zonula occludens-1 (ZO-1); transepithelial electrical resistance; oxidative stress; 2',7'-dichlorofluorescein (DCF); glutathione.

Received 2 October 2007; accepted 26 June 2008.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Multimed Inc. logo
Copyright © 2009 by Multimed Inc.