Document Detail


Cytokine modulation of Na(+)-dependent glutamine transport across the brush border membrane of monolayers of human intestinal Caco-2 cells.
MedLine Citation:
PMID:  1616390     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Previous studies have demonstrated that Na(+)-dependent brush border glutamine transport is diminished in septic patients. To examine the potential regulation of this decreased transport by endotoxin, cytokines, or glucocorticoids, the human intestinal Caco-2 cell line was studied in vitro. Na(+)-dependent glutamine transport across the apical brush border membrane was assayed in confluent monolayers of differentiated cells that were 10 days old. Uptake of 50 microM glutamine was determined after a 12-hour incubation with varying doses (10 to 1000 U/mL) of tumor necrosis factor-alpha, interleukin-1, interleukin-6, interferon-gamma, and various combinations of these cytokines. Studies were also done in cells incubated with E. coli endotoxin (1 micrograms/mL) or dexamethasone (1 and 10 microM). Endotoxin, tumor necrosis factor, interleukin-1, and interleukin-6 alone and in combination did not significantly reduce Na(+)-dependent glutamine transport across the brush border of Caco-2 cells. Dexamethasone decreased glutamine transport by 20%, but this decrease was not apparent for 48 hours. Interferon consistently decreased glutamine transport by 30%; this was due to a reduction in carrier maximal transport velocity (3427 +/- 783 pmol/mg protein/minute in controls versus 2279 +/- 411 in interferon, p less than 0.05) rather than a change in Km (276 +/- 29 microM in controls versus 333 +/- 74 in interferon, p = not interferon + dexamethasone + tumor necrosis factor + interleukin-1 resulted in a 38% decrease in transport activity. Cytokines and glucocorticoids may work independently and synergistically in regulating Na(+)-dependent brush border glutamine transport in human intestinal cells. Whether these signal molecules play a central role in the cause of the diminished brush border glutamine transport that occurs in septic patients requires further study.
Authors:
W W Souba; E M Copeland
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Annals of surgery     Volume:  215     ISSN:  0003-4932     ISO Abbreviation:  Ann. Surg.     Publication Date:  1992 May 
Date Detail:
Created Date:  1992-07-30     Completed Date:  1992-07-30     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  0372354     Medline TA:  Ann Surg     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  536-44; discussion 544-5     Citation Subset:  AIM; IM    
Affiliation:
Department of Surgery, University of Florida College of Medicine, Gainesville.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adenocarcinoma / pathology
Biological Transport, Active / physiology
Colonic Neoplasms / pathology
Cytokines / physiology*
Dexamethasone / pharmacology
Endotoxins / pharmacology
Glutamine / metabolism*
Humans
Microvilli / metabolism
Sodium / metabolism*
Tumor Cells, Cultured / metabolism*
Grant Support
ID/Acronym/Agency:
CA-45237/CA/NCI NIH HHS; HL-44986/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Cytokines; 0/Endotoxins; 50-02-2/Dexamethasone; 56-85-9/Glutamine; 7440-23-5/Sodium
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The effect of gastrin on growth of human stomach cancer cells.
Next Document:  Patterns of ileal recurrence in Crohn's disease. A prospective randomized study.