Protective effect and mechanism of esculetin on oxidative damaged ARPE-19 cells

Objective

To study the protective effect and the mechanism of esculetin on oxidative-stressed human retinal pigment epithelial cells (ARPE-19) induced by tert-butyl hydroperoxide (t-BHP).

Methods

The ARPE-19 cells were divided into blank control group, model control group, 20 μmol/L esculetin group, 40 μmol/L esculetin group, 80 μmol/L esculetin group and 100 μmol/L esculetin group.The cells in the blank control group were normally cultured.The cells in the model control group were treated with 900 μmol/L t-BHP for 4 hours.The rest four groups were treated with 900 μmol/L t-BHP+ different molar concentrations of esculetin respectively for 4 hours.The cell viability of the each group was detected by MTS method.The activity of reactive oxygen species (ROS) was detected by fluorescence staining, and the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) as well as the levels of malondialdehyde (MDA) of the cells from each group were measured with each corresponding assay kit, respectively.

Results

The relative viabilities of the cells in the blank control group, model control group, 20 μmol/L esculetin group, 40 μmol/L esculetin group, 80 μmol/L esculetin group and 100 μmol/L esculetin group were (100.00±1.58)%, (49.19±1.06)%, (76.82±3.48)%, (103.90±1.60)%, (111.70±3.36)% and (113.40±3.08)%, respectively.There was a significant difference among the groups (F=95.44, P<0.01). Compared with the blank control group, the viability of the cells in the model control group was decreased significantly (P<0.01). Compared with the model control group, the cell viabilities in different concentrations of esculetin groups were increased significantly (all at P<0.01). There were significant differences between the groups in the relative value of ROS fluorescence intensity, MDA level, SOD activity, CAT activity and GSH-Px activity (F=575.20, 40.61, 1 802.00, 41.62, 38.31; all at P<0.01). Compared with the model control group, the levels of ROS and MDA were decreased significantly, while the activities of SOD, CAT and GSH-Px were increased significantly in different concentrations of esculetin-treated groups (all at P<0.01).

Conclusions

Esculetin can protect the oxidative damaged ARPE-19 cells by up-regulating the expression of antioxidant enzymes or antioxidant proteins.