Protective effect of rhizoma dioscoreae and bone marrow mesenchymal stem cells in rats with renal ischemia-reperfusion injury

Objective To investigate the protective effect of rhizoma dioscoreae and bone marrow mesenchymal stem cells in rat with renal ischemia-reperfusion(I-R)injury.Methods Sixty female SD rats(4-6 weeks old)were randomly assigned into normal control(group A,n=6),I-R injury(group B,n=18),bone marrow mesenchymal stem cell(MACs)treatment(group C,n=18),and treated with rhizoma dioscoreae and MSCs(group D,n=18).The rats in group D were pretreated with rhizoma dioscoreae for five days before being subjected to left renal vascular occlusion for 60 min,those in group C and D were injected BrdU positive MSCs(1×106/ml)1 ml at 60 min after reperfusion.Rats in group B,C,and D were randomly euthanized for blood sampling and kidney harvesting at 6,48 h and 2 w after reperfusion.The blood urea nitrogen(BUN)and serum creatinine(SCr)were measured.The renal tissue homogenate content of endothelin(ET)was determined with radioimmunoassay.Renal morphologic changes were studied on hematoxylin and eosin(HE)stained sections.PCNA positive cells of renal tubular epithelia and glomeruruls were detected immunohistochemically as proliferation index.The distribution of BrdU positive MSCs and FⅧ-Rag positive cells were also identified immunohistochemically.Results BUN and SCr were significantly lower in group C,D than those in group B at 6 h after reperfusion.At 48 h after reperfusion,BUN and SCr were elevated only in group B and no difference was observed among the four groups 2 w after reperfusion.At 6 h after reperfusion,ET in group B,C was significantly higher than that in group A.ET was significantly lower in group C and D than that in group B,and no difference was observed between group D and group A.At 48 h after reperfusion,there were no significant differences in ET levels among the four groups.At 6 h and 48 h after reperfusion,BrdU positive MSCs were located in renal interstitium and glomerulus in group C and D.At 2 w after reperfusion,more BrdU positive MSCs were located at peritubular capillary and glomerulus.At 6 h,48 h and 2 w after reperfusion,PCNA positive cells and FⅧ-Rag positive cells were much more in group C,D than those in group B,which were more in group D than those in group C.Conclusion MSCs are of protective effect on renal I-R injury.Rhizoma dioscoreae and MSCs have synergistic action in ameliorating renal I-R injury.