ABSTRACT
AIM: To investigate the effects of antitumor drug paclitaxel(PTX)on the proliferation, apoptosis, cell cycle, cell morphology, and related protein expression of Müller cells, and to evaluate its potential toxicity to the retina.METHODS:Müller cells were cultured in vitro and divided into two groups: control group(normal medium)and PTX group. Retinal Müller cells were treated with different concentrations of PTX(0.005, 0.05, 0.5 and 5mg/L)for varying durations(12, 24, 36, 48 and 72h). The CCK8 method was used to assess the effects of different concentrations of PTX and treatment duration on the proliferation Müller cells. Flow cytometry was employed to investigate the impact of different concentrations of PTX on Müller cells apoptosis and cell cycle arrest. Immunofluorescence was used to observe morphological changes in Müller cells. The effects of PTX on the expression of apoptosis-related proteins and aquaporins were analyzed by Western blot and qRT-PCR.RESULTS: PTX exhibits the ability to inhibit the proliferation of Müller cells when cultured in vitro. The efficacy of this inhibition was found to be dependent on both the concentration of the drug and the duration of the stimulation. Higher concentrations of the drug and longer stimulation times resulted in a weaker ability of the cells to proliferate. Additionally, PTX also induces apoptosis in Müller cells, with increased drug concentrations and longer stimulation times leading to higher apoptosis rates. Flow cytometry analysis demonstrates that PTX arrests Müller cells in the G2-M phase of the cell cycle. Moreover, there is a distinct change in cell morphology, with a shift from the typical appearance characterized by clear and slender fibrous structures to a rounder morphology, accompanied by a significant decrease in cell numbers. Further, our findings reveal that there is a transient increase in the expression of cytoinflammatory factors following drug treatment compared to the control group. However, discontinuation of drug stimulation can alleviate this heightened expression. In treated cells, the expression of the CA XIV protein is upregulated compared to the control group, while the expression of vascular endothelial growth factor(VEGF)is downregulated(P<0.05). Additionally, the levels of inflammatory factors in the PTX group are significantly higher than those in the control group(P<0.05), suggesting that PTX has the potential to disrupt the retinal barrier function.CONCLUSION: PTX affects the proliferation and apoptosis of Müller cells, with the effects dependent on stimulation duration and drug concentration. In addition, PTX blocks the Müller cell cycle at the G2-M phase and alters cell morphology, leading to a transient upregulation of inflammatory factors and affecting the integrity of the retinal barrier. These findings indicate the potential toxicity of the antitumor drug PTX to the retina.
ABSTRACT
@#AIM: To investigate the potential toxic effects of paclitaxel(PTX)on the proliferation, apoptosis, cell cycle, morphology, and blood-retinal barrier(BRB)of human retinal pigment epithelial cells(ARPE-19). <p>METHODS: ARPE-19 cells were cultured <i>in vitro</i> and divided into two groups: Control group(Control)and drug plus group(PTX). ARPE-19 cells were treated with different concentrations of PTX(0.005, 0.05, 0.5, 5mg/L)for a certain period of time(12, 24, 36, 48, 72h), and CCK8 assay and flow cytometry were used to detect the effects of drug on proliferation and apoptosis of ARPE-19 cells at different concentrations and time points. The same time, the cell cycle was detected by flow cytometry. Morphological changes of cells were observed by immunofluorescence. Expressions of apoptosis-related proteins and barrier function-related proteins were detected by Western blot. The effect of the drug on the cell barrier was measured by measuring the transepithelial resistance of the cells. <p>RESULTS: PTX reduced the proliferation ability of ARPE-19 cells. After 36h of treatment with low concentration of 0.005mg/L paclitaxel, cell proliferation began to be affected. At the same time, PTX accelerated cell apoptosis was dependent on drug concentration and time. Flow cytometry showed that the cells were arrested in the G2-M phase. In addition, PTX causes significant morphological changes in cells, with normal cells fusiform or irregular. In the PTX group, the number of cells decreased and the cell shape tended to be round. PTX affected retinal barrier function, and the transepithelial resistance of cells was significantly decreased after treatment, and the expression of tight junction proteins ZO-1 and Occludin were significantly decreased compared with the control group(<i>P</i><0.05). The expression levels of Cleaved-caspase-3 and Bax were significantly increased compared with the control group, while the expression levels of Bcl-2 were significantly decreased(<i>P</i><0.05)and was dependent on drug concentration and time. <p>CONCLUSION: PTX can affect the proliferation and apoptosis of ARPE-19 cells, and it depends on time and concentration. In addition, PTX affected the cell cycle and morphology of ARPE-19 cell. At the same time PTX can destroy the barrier function of the retina,suggesting that anti-tumor drugs have a potential toxic effect on the retina.