Effects of UCMSCs Delivered through Different TransplantationApproaches on Acute Radiation Enteritis in Rats

摘要

Radiation enteritis is the most common and serious complication of abdominal orpelvic radiation therapy. Mesenchymal stem cells (MSCs), as well as cellprotection agents, inhibit apoptosis and promote the proliferation of injuredtissues. 3 human umbilical cords MSCs (UCMSCs) were injected into the tail veinor peritoneal cavity of a rat model of radiation enteritis. The temporaryprotective effect was assessed by identification of donor cells, detection ofcellular immune parameters and inflammatory cytokine levels, quantitation ofjejunum mucosal preservation and examination of the rat remaining life. Only therats in the intraperitoneal injection group exhibited a few positive donor cells7 days after transplantation. CD4+/CD8+ T cells, a cellular immune parameter, decreased in the abdominalexudate of intraperitoneal injection group, compared with the model-only controland tail vein groups (both P < .05). Both serum andabdominal exudate TNF-α and IL-6 levels in the intraperitoneally injected ratsrapidly decreased and were significantly different from those in the model-onlycontrol and tail vein injection groups (all P < .05).Mucosal surface area and survival time increased in the intraperitonealinjection group compared with the vehicle and tail vein injection groups (allP = .000). Therefore, the administration of UCMSCs withintraperitoneal injection approach postponed death in a rat model of radiationenteritis, which was associated with reduced serum levels of proinflammatorycytokines (TNF-α, IL-6). However, UCMSCs injected via the tail vein triggered anintense cellular immune response in the serum that adversely affects theirsurvival. This treatment failed to suppress circulating serum and abdominalexudate levels of TNF-α and IL-6 and could not provide a therapeutic benefit forprolonging life against acute radiation enteritis.