Heparin-binding EGF-like growth factor decreases inducible nitric oxide synthase and nitric oxide production after intestinal ischemia/reperfusion injury

• Published in: Antioxidants & redox signaling Vol. 3; no. 5; p. 919
• Main Authors: Xia, G, Lara-Marquez, M, Luquette, M H, Glenn, S, Haque, A, Besner, G E
• Format: Journal Article
• Language: English
• Published: United States 01-10-2001
• Subjects: Animals; Blotting, Western; Down-Regulation; Epidermal Growth Factor - chemistry; Epidermal Growth Factor - metabolism; Heparin-binding EGF-like Growth Factor; Humans; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Intestines - drug effects; Luminescent Measurements; Male; Nitrates - blood; Nitric Oxide - biosynthesis; Nitric Oxide Synthase - biosynthesis; Nitric Oxide Synthase Type II; Nitrites - blood; Rats; Rats, Sprague-Dawley; Recombinant Proteins - metabolism; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - metabolism; RNA, Ribosomal - metabolism; Transcription, Genetic
• ISSN: 1523-0864
• DOI: 10.1089/15230860152665073

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been shown to protect intestine from ischemia/reperfusion (I/R) injury in vivo and to down-regulate inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in intestinal epithelial cells in vitro. The present study was undertaken to investigate whether HB-EGF could modulate the iNOS/NO axis after total midgut I/R injury in rats. I/R injury induced a significant increase in iNOS gene expression (quantified by real-time RT-PCR) and protein production (detected by western blots), as well as elevation of serum NO levels (measured by chemiluminescence assay). Nitrotyrosine (NT) and iNOS production colocalized immunohistochemically, with positive staining found mainly in villous and crypt epithelial cells, as well as ganglion cells. Intraluminal administration of HB-EGF 45 min after the start of a 90-min ischemic interval significantly decreased I/R-induced iNOS gene expression and protein production, as well as serum NO levels. Immunohistochemically, HB-EGF administration led to elimination of iNOS and NT staining in crypt epithelial cells and ganglion cells, with only weak staining that remained in villous epithelial cells. Thus, HB-EGF protects the intestine from I/R injury, at least partially, through down-regulation of the iNOS/NO/NT pathway, a mechanism that is central to I/R injury in multiple organ systems.