Urine-Derived Mesenchymal Stromal Cells Alleviate Radiation-Induced TGF-β1 Production through the Inhibition of the NF-κB Signaling Pathway in MRC-5 Cells.

No effective therapeutic method is available for the treatment of radiation pulmonary fibrosis. Recent studies have suggested that urine can provide an effective and noninvasive source of many differentiating or differentiated progenitor cells and stem cells. The aim of our present study was to assess the therapeutic effects of human urine-derived mesenchymal stromal cells (uMSCs) in a cell model of radiation pulmonary fibrosis. MRC-5 cells were irradiated and cultured in the presence of conditioned medium from uMSCs (MSCCM). MSCCM inhibited MRC-5 cell proliferation and reduced collagen deposition as measured by CCK-8 assay, Sircol assay, qPCR and western blot. MSCCM also reduced the expression of the pro-fibrotic TGF-β1 and increased the expression of anti-fibrotic IFN-γ at both mRNA and protein levels. Furthermore, we found that MSCCM inhibited the activation of NF-κB signaling pathway induced by irradiation as well. Our data suggest that MSCCM could reduce irradiation-induced TGF-β1 production and ameliorate collagen deposition by inhibiting NF-κB signaling pathway. Our present study provides new insights into the treatment effect of uMSCs in radiation pulmonary fibrosis. [ABSTRACT FROM AUTHOR]