Milk fat globule epidermal growth factor-factor 8 mitigates inflammation and tissue injury after hemorrhagic shock in experimental animals

Abstract

Background Insufficient clearance of apoptotic cells leads to increased inflammation and exaggerated organ injury. The opsonizing protein, milk fat globule EGF-factor 8 (MFG-E8), upregulates apoptotic cell clearance. The purpose of this study was to determine the degree of apoptotic cell clearance, and if inflammation, organ injury and survival are improved following treatment with recombinant human MFG-E8 (rhMFG-E8) after hemorrhagic shock. Methods Male mice underwent a pressure-controlled (25±5 mmHg) model of hemorrhagic shock for 90 min. They were resuscitated with normal saline with or without rhMFG-E8 over 30 min. At 3.5 h post-resuscitation, blood and tissue were collected. MFG-E8 levels in the plasma, lungs and spleen were measured. Apoptotic cell clearance was measured by cleaved caspase-3 levels and TUNEL staining. Neutrophil infiltration was assessed using myeloperoxidase activity in the lungs and spleen. Plasma and tissue levels of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) were measured by ELISA. Finally, a 7-day survival study was also conducted. Results MFG-E8 levels in the plasma, lungs and spleen significantly decreased by 33%, 44%, and 55%, respectively, at 3.5 h following hemorrhage and resuscitation. Treatment with rhMFG-E8 significantly improved apoptosis, by reducing TUNEL+ cells after treatment and restoring cleaved caspase-3 expression back to baseline. Neutrophil infiltration was blunted by 29% and 41% in the lungs and spleen, respectively. Cytokine expression was also reduced significantly, by 64–73% in plasma, 24–58% in the lungs and 49–76% in the spleen. Finally, animals demonstrated a superior survival rate over 7 days after treatment with rhMFG-E8. Conclusion The administration of rhMFG-E8 is a potent treatment in animals following hemorrhagic shock.

Recombinant human MFG-E8 ameliorates colon damage in DSS- and TNBS-induced colitis in mice

“…It is also possible that the human form of MFG-E8 may be less potent in the mouse, as the homology between human and mouse MGF-E8 is only 56%. Nevertheless, rhMFG-E8 is clearly active in rodents, as we have demonstrated previously [31][32][33][34][35] and in the present study. Therefore, rhMFG-E8 is expected to have comparable beneficial effects in humans with IBD.…”

“…[31][32][33][34][35] We have injected mice with up to 2560 μg/kg rhMFG-E8 intravenously, and observed no alteration in liver transaminases (AST and ALT) 24 h later (unpublished observations). More comprehensive studies, however, will need to be conducted to exclude any toxicity.…”

MFGE8/Integrin β3 pathway alleviates apoptosis and inflammation in early brain injury after subarachnoid hemorrhage in rats

“…Therefore, MFGE8 may form a bridge to connect with phagocytic cells and apoptotic cell. It has been reported that exogenous MFGE8 attenuated inflammation injury by increasing apoptotic cell clearance in various model, including cerebral ischemic injury (Cui et al, 2010; Kranich et al, 2010; Lauber et al, 2013; Matsuda et al, 2011b; Wu et al, 2012; Zhang et al, 2012). In the present study, rhMFGE8 reduced the expression of the apoptosis executor cleaved caspase 3, and knockdown of endogenous MFGE8 potentiated the expression of cleaved caspase 3 after SAH.…”

Redefining the gut as the motor of critical illness

“…HB-EGF likely promotes its beneficial effects in multiple fashions, including promoting integrin-extracellular matrix interactions as well as intercellular adhesions (74) and preventing intestinal stem cells from injury under pathological conditions (75). Additionally, milk fat globule-EGF factor 8 also improves survival in both CLP and hemorrhagic shock and decreases both inflammation and tissue injury although its impact on intestinal permeability is unknown (76;77). …”