Hyperpermeability and ATP depletion induced by chronic hypoxia or glycolytic inhibition in Caco-2BBe monolayers

Naoki Unno, Michael J. Menconi, Andrew L. Salzman, Marianne Smith, Susan Hagen, Yimin Ge, Robert M. Ezzell, Mitchell P. Fink

Research output: Contribution to journalArticlepeer-review

88 Scopus citations

Abstract

Previous studies have documented that the barrier function of epithelial or endothelial monolayers is deranged when cellular ATP levels are rapidly decreased to very low levels by inhibitors of mitochondrial and glycolytic function. We hypothesized that lesser degrees of ATP depletion also might affect epithelial permeability, particularly if the perturbation were sustained for a prolonged interval. Using Caco-2BBe cells grown on permeable supports mounted in bicameral chambers, we assessed permeability by measuring the apical-to-basolateral clearance (flux divided by apical compartment concentration) of fluorescein disulfonic acid. ATP was depleted by incubating cells in glucose-free (Glu-) medium containing 10 mM 2-deoxyglucose (2-DOG) for 12, 24, or 48 h or under an anoxic atmosphere for 24, 48, or 72 h. Although both models of energy depletion were characterized by significant derangements in barrier function, metabolic inhibition with 2-DOG/ Glu- resulted in greater increases in permeability and more profound decrements in cellular ATP content. Morphological studies using electron and confocal fluorescence microscopy showed structural changes in individual cells and derangements in the normal distribution of perijunctional actin after monolayers were incubated with 2-DOG/Glu- but not after incubation under an anoxic atmosphere. Addition of 10 mM lactic acid (final pH 6.7) provided significant protection against both hyperpermeability and ATP depletion induced by 2-DOG/Glu-. We conclude that moderate degrees of ATP depletion are sufficient to increase the permeability of Caco2BBe monolayers and that lactic acidosis helps to preserve ATP content, barrier function, and morphological integrity in hypoxic intestinal epithelial cells.

Original languageEnglish (US)
Pages (from-to)G1010-G1021
JournalAmerican Journal of Physiology
Volume270
Issue number6 PART 1
DOIs
StatePublished - 1996

Keywords

  • Acidosis
  • Adenosine 5′-triphosphate
  • Barrier function
  • F-actin
  • Mitochondria

ASJC Scopus subject areas

  • Physiology (medical)
  • Gastroenterology
  • Physiology

Fingerprint Dive into the research topics of 'Hyperpermeability and ATP depletion induced by chronic hypoxia or glycolytic inhibition in Caco-2BBe monolayers'. Together they form a unique fingerprint.

Cite this