For example, Li et al. showed that mouse UC-MSC paracrine alleviated renal fibrosis by decreasing the deposition of fibronectin and collagen I, and elevated the levels of MMP2 and MMP9, and the mechanism may be related to TGF-β1-triggered myofibroblast transdifferentiation, and PI3K/Akt and MAPK signaling pathways [47]. Here, TGFB1 is linked to renal fibrosis.