Adipose-derived mesenchymal stem cell-conditioned medium and proliferation of intestinal stem cells in mesenteric...

Mesenteric ischemia frequently causes bowel necrosis even after recirculation, known as reperfusion injury, and no effective therapy has been validated for preserving the intestine. Adipose-derived mesenchymal stem cell-conditioned medium (MSC-CM), a tissue engineering and regenerative therapy, has been suggested as a feasible acute-phase treatment for organ damages. This study aimed to elucidate the therapeutic effects of MSC-CM on intestinal tissue injuries by ischemia and reperfusion. Mice were categorized into three groups that underwent either 60-min mesenteric artery occlusion (ischemia group), 60-min reperfusion following 60-min occlusion (reperfusion group), or ischemia-reperfusion with the same duration following intravenous administration of 200-µL MSC-CM by retroorbital injection (MSC-CM group). The distal ileum was harvested, and immunofluorescence staining with caspase-3 and LGR5, an intestinal stem cell-specific marker, was performed for evaluating the injury location and type of cells protected by MSC-CM. Moreover, LGR5, Notch1, Jagged 1, Hes1, DLL1, DLL3, and DLL4 mRNA expressions were measured using quantitative polymerase chain reaction. Ischemia extensively damaged the epithelial layer, and reperfusion-induced cellular apoptosis at the epithelial layer. MSC-CM administration was associated with preservation of cells at the crypt base, which were identified as intestinal stem cells using double-immunofluorescence staining. The MSC-CM group demonstrated significantly higher LGR5 expression than the reperfusion and ischemia groups. Similarly, the MSC-CM group exhibited higher Notch1 and Jag1 expressions, whereas the reperfusion group showed a higher Notch1 expression. In conclusion, MSC-CM use was associated with preservation of the intestinal stem cells at the crypt of villi and higher Notch1 and Jag1 expressions.