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Published on: January 30, 2018

Activation of the kappa-opioid receptor in Caco-2 cells decreases interleukin-8 secretion

Brien L Neudeck1, Jennifer Loeb, Jessica Buck

  • 1University of Wisconsin School of Pharmacy, 777 Highland Avenue, Madison, WI 53705-2222, USA. blneudeck@pharmacy

European Journal of Pharmacology
|April 23, 2003
PubMed

Insights

Kappa-opioid receptor activation on intestinal Caco-2 cells reduces interleukin-8 secretion. This finding suggests a role for kappa-opioid agonists in modulating intestinal inflammation at the epithelial level.

Area of Science:

  • Gastroenterology
  • Immunology
  • Pharmacology

Background:

  • The immunomodulatory impact of kappa-opioid agonists on intestinal epithelial cells remains unclear.
  • Understanding these interactions is crucial for developing targeted therapies for gastrointestinal disorders.

Purpose of the Study:

  • To investigate the presence and function of kappa-opioid receptors on Caco-2 cells.
  • To determine the effect of kappa-opioid receptor activation on interleukin-8 secretion in intestinal epithelial cells.

Main Methods:

  • Caco-2 cells were treated with the kappa-opioid agonist U-50488.
  • Interleukin-8 secretion was measured in the presence of interleukin-1beta.
  • Reversibility of effects was assessed using the kappa-opioid receptor antagonist nor-binaltorphimine.

Main Results:

  • Caco-2 cells express the kappa-opioid receptor.
  • Activation of this receptor by U-50488 significantly decreased interleukin-8 secretion.
  • The observed effects were dose-dependent and reversible by nor-binaltorphimine.

Conclusions:

  • Kappa-opioid receptor activation on Caco-2 cells inhibits interleukin-8 secretion.
  • This mechanism may modulate the chemotactic response at the intestinal epithelial level.
  • Findings suggest a potential therapeutic role for kappa-opioid agonists in intestinal inflammation.

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