Involvement of stomach ghrelin and hypothalamic neuropeptides in tumor necrosis factor-alpha-induced hypophagia in mice

Regul Pept. 2007 Apr 5;140(1-2):94-100. doi: 10.1016/j.regpep.2006.11.022. Epub 2006 Dec 21.

Abstract

This study aimed to clarify the interaction of tumor necrosis factor-alpha (TNF-alpha), an anorexigenic cytokine, with ghrelin, an orexigenic peptide secreted by the stomach lining, and hypothalamic neuropeptides in the regulation of food intake in mice. The peripheral administration of TNF-alpha dose-dependently decreased the 24-h cumulative food intake compared with the administration of saline. Reduced food intake was observed at 6 h and 24 h. The same TNF-alpha treatment significantly decreased the plasma level of ghrelin at 6 h and 24 h after treatment compared with the control levels. These changes were accompanied by a significant reduction in the expression of ghrelin mRNA in the stomach at 24 h after treatment. TNF-alpha treatment also resulted in a significant increase in expression of pro-opiomelanocortin (POMC) mRNA and a significant decrease in expression of agouti-related protein (AGRP) mRNA in the hypothalamus at 6 h after treatment. Finally, the pre-administration of ghrelin, reversed the TNF-alpha-induced hypophagia in mice at 6 and 24 h. Taken together, these findings suggest that hypothalamic POMC and AGRP and stomach ghrelin may be involved in TNF-alpha-induced hypophagia in mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Eating / drug effects
  • Gastric Mucosa / metabolism
  • Gene Expression / drug effects
  • Ghrelin
  • Humans
  • Hyperphagia / chemically induced
  • Hyperphagia / genetics*
  • Hyperphagia / metabolism
  • Hypothalamus / drug effects
  • Hypothalamus / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Neuropeptides / genetics*
  • Peptide Hormones / blood
  • Peptide Hormones / genetics*
  • Peptide Hormones / pharmacology
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Stomach / drug effects
  • Time Factors
  • Tumor Necrosis Factor-alpha / pharmacology*

Substances

  • Ghrelin
  • Neuropeptides
  • Peptide Hormones
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha