Abstract:

Objective To understand the effect of human umbilical cord mesenchymal stem cells（hUC⁃ MSCs） on myofibroblasts and to explore the effect of artesunate combined with hUCMSCs on myofibroblasts. Methods hUC⁃MSCs were isolated from umbilical cord by type Ⅱ collagenase digestion and adherence method. Human embryonic lung fibroblasts（MRC⁃5）were induced by TGF⁃β1 for 48 h，then added to MSCs and or ART for 24 h. Besides，after removal of the MSCs，TGF⁃β1 was readded into the MSC⁃deMFB system. The apoptosis level and the proliferation of cells were detected by flow cytometry and CCK8，respectively. The mRNA and protein expression levels of α ⁃ SMA，collagen and fibronectin were detected by qPCR and WB，respectively. Results hUCMSCs used in the experiment met the ISCT MSC criteria. After TGF⁃β1 pretreatment of MRC⁃5（MFB），cells were co ⁃cultured with MSCs for 24 h and the CCK8 increased compared with the control group（P < 0.01）. The mRNA and protein expression of α⁃SMA，COL1A1 and Fibronectin were significantly lower and close to the initial level of fibroblasts. When TGF ⁃ β1 was re ⁃added to the MSC ⁃ deMFB system，the cells recovered myofibroblasts characteristics，suggesting that MSC⁃induced myofibroblasts dedifferentiation was reversible. When myofibroblasts were stimulated by artesunate and MSCs simultaneously ，the cell apoptosis rate increased compared with the control group and it further inhibited the mRNA and protein expressions of α ⁃ SMA and COL1A1（P < 0.01）. Conclusions hUCMSCs can induce proliferation，dedifferentiation and inhibit extracellular matrix synthesis oflung myofibroblasts. Artesunate can induce the apoptosis of MSC⁃deMFB and overcome the effects of MSC⁃induced proliferation of myofibroblasts. Artesunate in conjunction with hUCMSCs may be a novel anti⁃fibrosis strategy.

Key words:

human umbilical cord mesenchymal stem cells, artesunate, pulmonary myofibroblasts, dedifferentiation, apoptosis