PT  - JOURNAL ARTICLE
AU  - Ying H. Yang
AU  - William K. K. Wu
AU  - Emily K. K. Tai
AU  - Helen P. S. Wong
AU  - Emily K. Y. Lam
AU  - Wallace H. L. So
AU  - Vivian Y. Shin
AU  - Chi H. Cho
TI  - The Cationic Host Defense Peptide rCRAMP Promotes Gastric Ulcer Healing in Rats
AID  - 10.1124/jpet.106.102467
DP  - 2006 Aug 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 547--554
VI  - 318
IP  - 2
4099  - http://jpet.aspetjournals.org/content/318/2/547.short
4100  - http://jpet.aspetjournals.org/content/318/2/547.full
SO  - J Pharmacol Exp Ther2006 Aug 01; 318
AB  - Cathelicidin, a cationic host defense peptide, has been shown to promote cutaneous wound repair and reaches high levels in the gastric mucosa during infection and inflammation. Therefore, we investigated whether this peptide contributes to gastric ulcer healing in rats. Ulcer induction increased the expression of rat cathelicidin rCRAMP in the gastric mucosa. Further increase in expression of rCRAMP by local injection of rCRAMP-encoding plasmid promoted ulcer healing by enhancing cell proliferation and angiogenesis. rCRAMP directly stimulated proliferation of cultured rat gastric epithelial cells (RGM-1), which was abolished by inhibitors of matrix metalloproteinase (MMP), epidermal growth factor receptors (EGFR) tyrosine kinase, or mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase. rCRAMP also increased EGFR and ERK1/2 phosphorylation via an MMP-dependent mechanism. Knockdown of transforming growth factor α (TGFα), which is a ligand of EGFR, by small interfering RNA completely nullified the mitogenic signals evoked by rCRAMP in RGM-1 cells. These findings suggest that rCRAMP exhibits prohealing activity in stomachs through TGFα-dependent transactivation of EGFR and its related signaling pathway to induce proliferation of gastric epithelial cells. The American Society for Pharmacology and Experimental Therapeutics