Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

Abstract

Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis.

Capsaicin-Sensitive Sensory Nerves Are Necessary for the Protective Effect of Ghrelin in Cerulein-Induced Acute Pancreatitis in Rats

“…Pretreatment with this polypeptide inhibits the development of different experimental models of gastric lesions [ 11 , 12 , 13 ], as well as exhibits therapeutic effect in the course of oral [ 14 ], gastric [ 15 , 16 ] and duodenal [ 15 , 17 ] ulcers. In addition, most experimental studies on the role of ghrelin in colitis indicates that administration of this peptide exhibits protective and therapeutic effect in the large bowel [ 18 , 19 , 20 , 21 , 22 , 23 ]. Protective and therapeutic effect of ghrelin was also found in the pancreas.…”

N-Methylcytisine Ameliorates Dextran-Sulfate-Sodium-Induced Colitis in Mice by Inhibiting the Inflammatory Response

“…However, free radicals, such as reactive oxygen and nitrogen species, can damage body cells, leading to the destruction of proteins, DNA and lipids. Eventually, such destruction causes colonic tissue damage and mucosal dysfunction, which play a significant role in the pathogenesis of IBD [ 30 ]. The level of MPO activity adequately reflects the degree of tissue infiltration by neutrophils.…”

Insulin-Like Growth Factor-1 as a Possible Alternative to Bone Morphogenetic Protein-7 to Induce Osteogenic Differentiation of Human Mesenchymal Stem Cells in Vitro

“…The ability of IGF-1 to promote this regeneration of tissue is associated with a reduction in pro-inflammatory cytokines and a corresponding stimulation of anti-inflammatory cytokines [ 31 ]. Additionally, ghrelin, a growth hormone secretagogue produced mainly in the stomach, was shown to exhibit protective and regenerative effects in various tissues via an increase in the release of endogenous IGF-1 and growth hormone [ 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ]. A recent study also found ghrelin promoted an increased expression of homeobox protein B4 in rat bone marrow stromal cells, which is a transcription factor involved in stem cells’ survival and regeneration [ 42 ].…”