Boldine promotes stemness of human urine-derived stem cells by activating the Wnt/ß-catenin signaling pathway.

Human urine-derived stem cells (hUSCs) process self-renewal and multilineage differentiation ability. Due to their non-invasive and easily available clinical source, hUSCs represent a promising alternative source of mesenchymal stem cells (MSCs) for application potential in cytotherapy. However, technical limitations, such as stemness property maintenance, have hindered hUSCs' clinical application. Certain some small molecules have been recognized with advantage in maintaining the stemness of stem cells. In this study, we identified stemness-regulated key targets of hUSCs based on the StemCellNet database, CMAP database and literature mining. Furthermore, we identified a small molecule compound, boldine, which may have the potential to promote the stemness of hUSCs. It promotes cell proliferation, multilineage differentiation and maintains stemness of hUSCs by cell viability assay, single-cell clone formation, osteogenic differentiation and stemness marker expression (OCT-4 and C-MYC). We identified that boldine may be a potential GSK-3ß inhibitor by molecular docking and confirmed that it can upregulate the level of ß-catenin and promote translocation of ß-catenin into nucleus of hUSCs using Western blotting and immunofluorescence analysis. Our study indicates boldine activates the Wnt/ß-catenin signaling pathway in hUSCs and provides an effective strategy for MSCs research and application of small molecules in maintaining the stemness of hUSCs.

Inducing differentiation of human urine-derived stem cells into hepatocyte-like cells by coculturing with human hepatocyte L02 cells.

OBJECTIVES: To investigate the possibility of inducing differentiation of human urine-derived stem cells (hUSCs) into hepatocyte-like cells by coculturing with human hepatocyte L02 cells in vitro. METHODS: HUSCs were isolated from fresh urine samples collected from healthy adult volunteers by centrifugation. Cells were observed under an inverted phase contrast microscope, and proliferative activity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Stem cell surface markers were detected by flow cytometry. HUSCs were induced to differentiate into hepatocyte-like cells by coculturing with human hepatocyte L02 cells, which were confirmed by cellular morphology, messenger RNA expression of albumin (ALB), α-fetoprotein (AFP) and hepatocyte cytochrome P450 (CYP450) analyzed with quantitative reverse transcription polymerase chain reaction and the expression of glycogen detected by glycogen staining kits at 5, 10, and 15 days after coculturing. RESULTS: HUSCs from urine were successfully isolated and cultured in vitro. At passages 3, the growth curve of hUSCs was S-shaped with good proliferation activity. Mesenchymal stem cell surface markers CD44 and CD90 were detected positive by flow cytometry. CD31 for endothelial cells and CD34 for hematopoietic stem cell markers were not detected. HUSCs gained the cellular morphology and function of hepatocyte cells including higher expression of several hepatocyte-specific genes such as ALB and some CYP450, lower expression of AFP and positive glycogen expression (P < .05) in coculturing with human hepatocyte L02 cells for 10-15d. CONCLUSIONS: HUSCs can be induced to differentiate into hepatocyte-like cells by coculturing with human hepatocyte L02 cells for a certain number of days.