Effect of metanephric mesenchymal stem cells after renal ischemia reperfusion injury in mice

Abstract

To study the effect of metanephric mesenchymal stem cells (MMSCs ) after renal ischemia reperfusion injury (IRI). C57BL/6J male mice were divided into control group (n=5) and experimental group (n=30). The control group was given a sham operation, while in the experimental group, a model of renal IRI was established. The experimental group was further divided into two groups according to the material injected through the femoral vein: IRI group (injected with normal saline, 10 ml/kg) and cell therapy group (injected with normal saline containing 5×10(5) MMSCs, 10 ml/kg). Samples of blood and kidney tissues were collected from five mice from each group at 12 h, 24 h and 72 h after IRI. The serum creatinine (SCr) level was detected, and the results of kidney tissue pathological staining and Paller score of renal tubules were analyzed to assess the effect of MMSCs after renal IRI. In addition, the expression of microRNA-26a(miR-26a)in kidney tissues was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and compared among the groups. (1) In both IRI group and cell therapy group, the levels of SCr at 12 h, 24 h and 72 h after operation were all significantly higher than those of the control group, besides, the level of SCr at 24 h was significantly higher than that at 12 h and 72 h (all P<0.05). The levels of SCr at 12 h, 24 h and 72 h were of no significant differences between IRI group and cell therapy group(all P>0.05). (2)Paller scores of renal tubules at 12 h, 24 h and 72 h in both IRI group and cell therapy group were significantly higher than those in the control group, and the scores at 24 h were significantly higher than that at 72 h, while the latter were in turn higher than the scores at 12 h (all P<0.05). In the cell therapy group, Paller score of renal tubules at 24 h(57.2±6.3)was significantly lower than that in IRI group(70.8±14.8) (P<0.05). Histological examination showed renal tubular epithelial cell atrophy, swelling and protein cast in kidney tissues from IRI group at 24 h, compared with the control group and the cell therapy group at the same time.(3) In IRI group and cell therapy group, the levels of miR-26a in the kidney tissues at 12 h and 24 h were significantly lower than those of the control group (P<0.05). In the cell therapy group, the level of miR-26a in the kidney tissues at 24 h (0.416±0.139) and 72 h (1.152±0.239)were significantly higher than that in the IRI group(0.244±0.067, 0.855±0.038, both P<0.05). A negative correlation between the levels of miR-26a and SCr level were found (r=-0.5, P<0.05). MMSCs have a certain repairing effect on renal IRI, accompanied by an increase in miR-26a expression.