Necrotizing enterocolitis (NEC) is an often catastrophic disease that typically affects premature newborns. Although the exact etiology of NEC is uncertain, the disease is associated with formula feeding, bacterial colonization of the gut, hypoxia, and hypoperfusion. In light of the pathogenesis of NEC, the integrity and function of the intestinal mucosa plays a major defensive role against the initiation of NEC. Various forms of intestinal injury, including NEC, injure the intestinal epithelial cell (IEC) lineages, including the intestinal stem cells (ISCs), thereby disrupting the normal homeostasis needed to maintain gut barrier function. In the current study we examined the effects of HB-EGF administration on enterocytes, goblet cells, neuroendocrine cells and intestinal stem cells in a newborn rat model of experimental NEC. We also examined the cytoprotective effects of heparin-binding EGF-like growth factor (HB-EGF) on intestinal stem cells in in vitro cell cultures and in ex vivo crypt-villous organoid cultures. We found that HB-EGF protects all intestinal epithelial cell lineages, including intestinal stem cells, from injury. We further found that HB-EGF protects isolated intestinal stem cells from hypoxic injury in vitro, and promotes intestinal stem cell activation and survival, and the expansion of crypt transit amplifying cells, in ex vivo crypt-villous organoid cultures. The protective effects of HB-EGF were dependent upon EGF receptor activation, and were mediated via the MEK1/2 and PI3K signaling pathways. These results demonstrate that the intestinal cytoprotective effects of HB-EGF are mediated, at least in part, through its ability to protect intestinal stem cells from injury.

Background-We have accumulated multiple lines of evidence supporting the ability of HB-EGF to protect the intestines from injury and to augment the healing of partial-thickness scald burns of the skin. The aim of the current study was to investigate the role of heparin-binding EGFlike growth factor (HB-EGF) in intestinal anastomotic wound healing.

Background Acute respiratory distress syndrome continues to be a major source of morbidity and mortality in critically-ill patients. Heparin binding EGF-like growth factor (HB-EGF) is a biologically active protein that acts as an intestinal cytoprotective agent. We have previously demonstrated that HB-EGF protects the intestines from injury in several different animal models of intestinal injury. In the current study, we investigated the ability of HB-EGF to protect the lungs from remote organ injury after intestinal ischemia/reperfusion (I/R). Methods Mice were randomly assigned to one of the following groups: 1) sham-operated; 2) sham + HB-EGF (1200 µg/kg in 0.6 mL administered by intra-luminal injection at the jejuno-ileal junction immediately after identification of the superior mesenteric artery); 3) superior mesenteric artery occlusion for 45 min followed by reperfusion for 6 h (I/R); or 4) I/R+HB-EGF (1200 µg/kg in 0.6 mL) administered 15 min after vascular occlusion. The severity of acute lung injury was determined by histology, morphometric analysis and invasive pulmonary function testing. Animal survival was evaluated using Kaplan-Meier analysis. Results Mice subjected to intestinal I/R injury showed histological and functional evidence of acute lung injury and decreased survival compared to sham-operated animals. Compared to mice treated with HB-EGF (I/R + HB-EGF), the I/R group had more severe acute lung injury, and decreased survival. Conclusion Our results demonstrate that HB-EGF reduces the severity of acute lung injury after intestinal I/R in mice. These data demonstrate that HB-EGF may be a potential novel systemic anti-inflammatory agent for the prevention of the systemic inflammatory response syndrome (SIRS) after intestinal injury.

Primary objective Heparin-binding EGF-like growth factor (HB-EGF) protects the intestine from damage in animals. Future clinical trials of HB-EGF may involve administration of repeated doses of HB-EGF. Since HB-EGF activates EGF receptors which have been implicated in tumor development, we examined the effects of HB-EGF overexpression in the intestine. Research design We generated transgenic (TG) mice in which the human HB-EGF gene is driven by the villin promoter to overexpress HB-EGF along the crypt-villous axis from the duodenum to the colon. Results HB-EGF TG mice have increased enterocyte proliferation balanced by increased enterocyte apoptosis. Despite prolonged overexpression of HB-EGF, no evidence of intestinal hyperplasia or tumor formation occurs. Although HB-EGF TG mice have no significant phenotypic alterations under basal conditions, they have increased resistance to intestinal injury. Conclusions Prolonged intestinal HB-EGF overexpression results in no significant phenotypic alterations under basal conditions, but confers protection against intestinal injury.