The renoprotective effect of bone marrow-derived endothelial progenitor cell transplantation on acute ischemia-reperfusion injury in rats.

OBJECTIVE

To investigate the renoprotective effects of exogenous endothelial progenitor cells (EPCs) on acute renal ischemia-reperfusion (I/R) injury in rats.

METHODS

EPCs were collected by in vitro culture of mononuclear cells derived from rat bone marrow. The EPC labeling was performed using chloromethyl-benzamidodialkylcarbocyanine (CM-Dil). Sprague-Dawley rats were equally randomized into an I/R, an EPC, and a control group. We evaluated blood urea nitrogen (BUN) and serum creatinine (Scr), kidney morphology, apoptosis and microvessel density. EPC homing into I/R injured kidneys was observed using a fluorescence microscope.

RESULTS

After EPC transplantation, CM-Dil-labeled EPCs were noted at the corticomedullary junction of injured kidneys. The levels of BUN and Scr were markedly lower among the EPC than the I/R group (P < .05). The histopathologic score was higher in the I/R than the EPC group (P < .05). Apoptosis of tubular epithelial cells was substantially reduced among EPC-treated rats (P < .01). In addition, more CD34(+) microvessels were documented among the EPC than the other two groups (P < .01). The expression levels of vascular endothelial growth factor (VEGF) were also increased greatly in the EPC group (P < .05).

CONCLUSION

Transplanted exogenous EPCs exert protective effects on renal function by maintaining the integrity of peritubular capillaries after I/R injury.