Pretreatments with injured microenvironmental signals altered the characteristics of human umbilical cord mesenchymal stem cells.

ABSTRACT

OBJECTIVE: Human umbilical cord mesenchymal stem cells (hUCMSCs) have renoprotective effects but the influence of the microenvironment on characteristics of hUCMSCs has not been well studied. Here, we investigate the effects of injury conditions on properties of hUCMSCs. RESULTS: hUCMSCs were treated in vitro under conditions mimicking the injury microenvironment of acute kidney injury. Cells stimulated with factor-treated medium proliferated slowly at first but quickly afterwards their morphology subsequently changed from spindle to stellate shape. Increased number of cells with strong expression of thymine-1 (Thy-1) or α-smooth muscle actin (α-SMA) was detected at 1 or 2 weeks after stimulation. Hepatocyte growth factor (HGF) level markedly increased after culture for 6 h under hypoxia condition. The expressions of HGF and insulin growth factor-1 (IGF-1) were significantly up-regulated from 0.22 ± 0.03 to 0.9 ± 0.02 and 0.07 ± 0.03 to 0.19 ± 0.01 in H/R-treated hUCMSCs respectively. Co-culture with injured renal tubular epithelial cells significantly promoted the expression of HGF (1.19 ± 0.21) and IGF-1 (0.24 ± 0.03) in hUCMSCs. CONCLUSION: The characteristics of hUCMSCs change in response to inured conditions, which may enhance the efficacy of stem cell therapy and provide novel strategies in maximizing biological and functional properties of hUCMSCs.