Enhanced Effect of IL-1β-Activated Adipose-Derived MSCs (ADMSCs) on Repair of Intestinal Ischemia-Reperfusion Injury via COX-2-PGE2 Signaling

Adipose-derived mesenchymal stem cells (ADMSCs) have been used for treating tissue injury, and preactivation enhances their therapeutic effect. This study is aimed at investigating the therapeutic effect of activated ADMSCs by IL-1β on the intestinal ischaemia-reperfusion (IR) injury and exploring potential mechanisms. ADMSCs were pretreated with IL-1β in vitro, and activation of ADMSCs was assessed by α-SMA and COX-2 expressions and secretary function. Activated ADMSCs was transplanted into IR-injured intestine in a mouse model, and therapeutic effect was evaluated. In addition, to explore underlying mechanisms, COX-2 expression was silenced to investigate its role in activated ADMSCs for treatment of intestinal IR injury. When ADMSCs were pretreated with 50？ng/ml IL-1β for 24？hr, expressions of α-SMA and COX-2 were significantly upregulated, and secretions of PGE2, SDF-1, and VEGF were increased. When COX-2 was silenced, the effect of IL-1β treatment was abolished. Activated ADMSCs with IL-1β significantly suppressed inflammation and apoptosis and enhanced healing of intestinal IR injury in mice, and these effects were impaired by COX-2 silencing. The results of RNA sequencing suggested that compared with the IR injury group activated ADMSCs induced alterations in mRNA expression and suppressed the activation of the NF-κB-P65, MAPK-ERK1/2, and PI3K-AKT pathways induced by intestinal IR injury, whereas silencing COX-2 impaired the suppressive effect of activated ADMSCs on these pathway activations induced by IR injury. These data suggested that IL-1β pretreatment enhanced the therapeutic effect of ADMSCs on intestinal IR injury repairing via activating ADMSC COX-2-PGE2 signaling axis and via suppressing the NF-κB-P65, MAPK-ERK1/2, and PI3K-AKT pathways in the intestinal IR-injured tissue