Intestinal Epithelial Cell Derived Exosomes Package MicroRNA-23a-3p Alleviate Gut Damage After Ischemia/Reperfusion via Targeting MAP4K4

Abstract

Backgroud: Intestinal epithelial cells (IEC) contribute to regulate gut injury after intestinal isochemia/reperfusion (II/R). Exosomes are well documented to deliver bioactive molecules to recipient cells to modulate cell function. However, the role of IEC-derived exosomes in gut damage after II/R and the underlying mechanisms remains unclear. Methods IEC-derived exosomes were intravenously injected into the rats after the superior mesenteric artery occlusion for 45 min following reperfusion for 6h. The scores of gut injury, ZO-1 and IL-17A expression, TNF-α and endotoxin concentration were determined at 3 days after II/R assault. Exosomal microRNA-23a-3p and its downstream target molecule-MAP4K4 were also detected. Results Our results showed that the IEC-derived exosomes attenuated the damage of IECs after oxygen-glucose deprivation in vitro (p<0.05) and the degree of gut injury at 3 days after II/R assault in vivo (p<0.05). Injection of miR-23a-3p knockdown exosomes derived from IECs aggravated the II/R injury whereas PF-6260933, a small-molecule inhibitor of MAP4K4, was partly reversed the injuried degree by intraperitoneal injection. Underlying mechanism studies revealed that exosomal miR-23a-3p attenuated gut damage by regulating its downstream target MAP4K4. Conclusions We demonstrated that IEC-derived exosomes alleviated the II/R injury and promoted gut damage recovery via exosomal miR-23a-3p and its downstream target molecule-MAP4K4.