The aim of this study is to investigate the effects of aquaporin 1 (AQP1) on proliferation, migration and function maintenance of human corneal endothelial (HCE) cells and its related mechanisms.

pcDNA3.1 as a carrier, AQP1 overexpression plasmid (pcDNA3.1-AQP1), empty control plasmid (pcDNA3.1-NC), AQP1 small interfering ribonucleic acid sequence (siRNA-AQP1), and control sequence (siRNA-NC) were transfected into HCE cells, respectively. According to transfection types, cells were divided into non transfection control group (Control group), pcDNA3.1-AQP1 group, pcDNA3.1-NC group, siRNA-AQP1 group, and siRNA-NC group. The effect of AQP1 on the proliferation, migration, and apoptosis of HCE cells were evaluated.The expression of AQP1 mRNA in cells was detected by qRT-PCR. The ability of cell proliferation was detected by EdU assay. The cell migration ability was detected by Transwell chamber method. The apoptosis was detected by flow cytometry.To clarify the role of p38 mitogen activated protein kinase (p38 MAPK) signaling pathways in its mechanisms, p38 MAPK activator 10 μmol/L anisomycin was added to the pcDNA3.1-AQP1 group and called the pcDNA3.1-AQP1+ anisomycin group. The protein expression levels of human tight junction protein 1 (TJP1), sodium potassium triphosphate adenylase (Na⁺ /K⁺ -ATPase), p38 MAPK, and phosphorylated p38 MAPK in HCE cells were detected by Western blot.The relative expression level of AQP1 mRNA, cell proliferation activity, migration rate, apoptosis rate, the expression level of TJP1 and sodium potassium triphosphatase protein, and phosphorylation p38 MAPK/p38 MAPK ratio in each group of cells conformed to the homogeneity of variance and normal distribution, represented by ±s, and independent sample t-test was used for intergroup comparison.

The relative expression of AQP1 mRNA of Control group, pcDNA3.1-NC group, siRNA-NC group, pcDNA3.1-AQP1 group and siRNA-AQP1 group were (1.00±0.08), (1.05±0.07), (0.97±0.07), (2.14±0.12) and (0.33±0.02). Compared with the Control group, there were no both signifcant differences between pcDNA3.1-NC group and siRNA-NC group (t=0.653, 0.684; P>0.05), indicating that cells with pcDNA3.1-NC and siRNA-NC were not affected, thus other indices of these cells were not detected again. The cell proliferation activity, the cell migration ratio, the apoptosis rate, the expression TJP1, Na⁺ /K⁺ -ATPase protein, and the ratio of phosphorylated p38 MAPK/p38 MAPK of pcDNA3.1-AQP1 group were (63.31±7.35)%, (74.28±7.04)%, (3.64±1.48)%, (1.73±0.13), (2.04±0.15) and (0.18±0.02), respectively; those of siRNA-AQP1 group were(22.15±3.26)%, (35.73±3.86)%, (20.35±2.83)%, (0.23±0.02), (0.21±0.02) and (0.75±0.09), respectively; those of pcDNA3.1-AQP1+ anisomycin group were (52.35±4.38)%, (58.74±5.42), (6.73±0.53)%, (1.38±0.21), (1.18±0.19) and (0.33±0.03), respectively. There were signifcant differences in all indices between pcDNA3.1-AQP1 group and Control group (t=3.844, 3.534, 3.253, 4.253, 4.753, 4.321; P<0.05); between siRNA-AQP1 group and Control group (t=4.136, 3.741, 3.621, 3.426, 4.122, 4.894, 3.795; P<0.05); between pcDNA3.1-AQP1 group and pcDNA3.1-AQP1+ anisomycin group(t=3.251, 3.363, 3.053, 3.242, 3.674, 4.264; P<0.05).

AQP1 overexpression can promote HCE cell proliferation and migration, inhibit apoptosis, and participate in the maintenance of HCE cell function, which may be relevant with the inhibition of p38 MAPK signaling pathway activation.