Systematic review and meta-analysis of mesenchymal stem/stromal cells therapy for impaired renal function in small animal models

Aim The meta-analysis of recent small animal experiments of mesenchymal stem/stromal cells (MSC) therapy for impaired kidney could provide significant clues to design large animal experiments as well as human clinical trials. Method A total of 21 studies was analyzed. These, were indexed from PubMed and Embase databases. All data were analyzed by RevMan 5.1 and SPSS 17.0. Pooled analysis and multivariable meta-regression were calculated by random effects models. Heterogeneity and publication bias across the studies were also explored. Results Pooled analysis showed elevated serum creatinine (Scr) reduction in the animal models of renal failure following MSC therapy. By exploratory multivariable meta-regression, significant influence factors of Scr reduction were the time point of Scr measurement (early measurement showed greater reduction than the late (P=0.005)) and the route of MSC delivery (arterial delivery of MSCs caused greater reduction in elevated Scr, when compared with the intra-renal delivery and intravenous injection (P=0.040)). Subgroup analysis showed there tended to be greater reduction in Scr with higher MSC number (>106), the renal ischemia-reperfusion injury (IRI) model, and late administration (>1 day) after injury. Conclusion The present meta-analysis confirmed that MSC therapy could improve impaired renal function. MSCs might get obvious effect in the early stage of renal injuries after arterial delivery. Further, this meta-analysis may provide important clues for animal experiments even for human clinical trials in MSC studies.