Abstract: 【Abstract】Objective To explore the effect of conditioned medium (CM) from human umbilical cord mesenchymal stem cells (hUC- MSCs) on high glucose (HG)- induced epithelial- mesenchymal transition (EMT) in human peritoneal mesothelium cells (HPMCs) and its underlying mechanism. Methods The effect of HG and mesenchymal stem cells conditioned medium (MSC-CM) on HPMCs proliferation was detected by CCK-8. HPMCs were divided into three groups: control group, HG group and CM group. Morphology changes of HPMCs were observed under microscope. The expressions of E- cadherin, vimentin, α-SMA and β-
catenin in HPMCs was detected by western blot. Results HG reduced the proliferation of HPMCs, and MSC-CM promoted the proliferation of HPMCs. Compared to control group, most HPMCs in HG group became spindle shape, and MSC-CM could alleviate the morphological changes of HPMCs. Compared to control group, HG treatment reduced the expression level of E-cadherin (0.730±0.049 vs. 0.934±0.008, t=7.166, P=0.002), and increased the expression levels of vimentin and α-SMA (vimentin: 0.897 ± 0.037 vs. 0.645± 0.110, t=3.748, P=0.020; α-SMA: 1.120±0.083 vs. 0.829±0.122, t=3.430, P=0.027), while MSC-CM significantly increased the expression of E-cadherin, and decreased the expressions of vimentin and α-SMA (E-cad-herin: 0.894 ± 0.055 vs. 0.730±0.049, t=3.865, P=0.018; vimentin: 0.737 ± 0.046 vs. 0.897 ± 0.037, t=4.657, P=0.010; α-SMA: 0.808±0.036 vs. 1.120± 0.083, t=6.000, P=0.004). Meanwhile, HG increased the expression of β-catenin in HPMCs (0.842±0.059 vs. 0.664±0.071, t= 3.341, P=0.029), while MSC-CM reduced the expression of β-catenin compared with HG group (0.613±0.086 vs. 0.842±0.059, t=3.808, P=0.019). Conclusions CM from hUC-MSCs attenuate high glucose-induced EMT by down-regulation of Wnt/β-catenin pathway in HPMCs..

Key words:  Peritoneal dialysis, Human peritoneal mesothelium cell, Epithelial-mesenchymal transition,  Human umbilical cord mesenchymal stem cell