RESUMO
Objective:To investigate the inhibitory effect of indocyanine green (ICG) on biological behavior and transdifferentiation of human lens epithelial cells (HLECs) and its mechanism.Methods:HLECs were divided into blank control group, 5% glucose solution (GS) group and 0.5% ICG group, 1.5% ICG group and 2.5% ICG group, which were treated with balanced salt solution, 5% GS and 0.5%, 1.5% and 2.5% ICG solutions for 3 minutes, respectively, and then were incubated in fresh medium for 24 hours.The apoptosis level of HLECs was detected by flow cytometry.The expression levels of apoptosis-related proteins, Bcl-2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2), caspase-3 and caspase-9 were detected by Western blot.Cell proliferation was detected via the cell counting kit-8 (CCK-8) assay and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay.The migration ability of HLECs was detected by cell scratch assay.Cell migration and invasion were determined by Transwell assays.The expression levels transdifferentiation-related proteins, α-smooth muscle actin (α-SMA), nerve calcium adhesion protein (N-cadherin), fibronectin (FN) and vimentin were assessed by Western blot.Results:The apoptosis rates of blank control group, 5% GS group, 0.5% ICG group, 1.5% ICG group and 2.5% ICG group were (4.35±0.60)%, (4.63±0.19)%, (8.17±0.69)%, (13.90±0.33)% and (23.08±1.12)%, with a statistically significant difference in the overall comparison ( F=412.74, P<0.05). The apoptosis rate was significantly higher in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group (all at P<0.05). The relative expressions of caspase-3, caspase-9 and Bax proteins were significantly higher in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group, and the relative expression of Bcl-2 protein was lower in 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group, and the differences were statistically significant (all at P<0.05). The rate of EdU-positive cells was significantly lower in 0.5% ICG group, 1.5% ICG group and 2.5% ICG groups than in blank control group and 5% GS group (all at P<0.05). The survival rate of cells was significantly lower in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group (all at P<0.05). The migration rates of scratch cells were significantly lower in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group, and the differences were statistically significant (all P<0.05). The number of migrating cells and the number of invading cells were significantly lower in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group (all at P<0.05). The relative expressions of α-SMA, N-cadherin and FN were significantly lower in 0.5% ICG group, 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group, and the relative expression of vimentin was lower in 1.5% ICG group and 2.5% ICG group than in blank control group and 5% GS group, and the differences were statistically significant (all at P<0.05). Conclusions:ICG can promote HLECs apoptosis and inhibit HLECs proliferation, migration, invasion and transdifferentiation in a concentration-dependent manner.