Protective Effect of Combined Caffeic Acid Phenethyl Ester and Bevacizumab Against Hydrogen Peroxide-Induced Oxidative Stress in Human RPE Cells

ABSTRACT

Purpose: This study aimed to evaluate the protective effects of caffeic acid phenethyl ester (CAPE) and combined CAPE-bevacizumab against oxidative stress induced by hydrogen peroxide (H₂O₂) in human retinal pigment epithelium.

Methods: ARPE-19 cells were pretreated with 5, 10, and 30 μM CAPE alone and in combination with bevacizumab for 3 h, then exposed to H₂O₂ for 16 h. Cell viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Vascular endothelial growth factor (VEGF) protein levels in the medium were measured using a human VEGF ELISA kit. Total antioxidant status (TAS) and total oxidant status (TOS) were measured in ARPE-19 cells using the test kit from Rel Assay. Expression levels of VEGF, Bax, Bcl-2, cytochrome c, apoptotic protease activating factor-1 (apaf-1), and caspase-3 were determined using reverse transcription polymerase chain reaction.

Results: Pretreatment of ARPE-19 cells with 30 μM CAPE and combined CAPE-bevacizumab reduced H₂O₂ mediated cell death. H₂O₂-induced oxidative stress increased TOS and VEGF production, which was significantly inhibited by CAPE and the CAPE-bevacizumab combination. VEGF, Bax, cytochrome c, apaf-1, and caspase-3 gene expressions were significantly decreased in cells pretreated with 5, 10, and 30 μM CAPE and combined CAPE-bevacizumab compared to the H₂O₂ group. In addition, Bcl-2 expression was significantly increased in both the CAPE and CAPE-bevacizumab combination groups compared to the H₂O₂ group.

Conclusions: CAPE has a protective effect on ARPE-19 cells against oxidative stress, and VEGF protein level and expression can be decreased by incubation with different concentrations of CAPE. These results demonstrate that CAPE suppresses the mitochondria-mediated apoptosis in ARPE-19 cells under oxidative stress. In addition, the use of CAPE in combination with bevacizumab has an additive effect.

KEYWORDS:

• Age related macular degeneration
• bevacizumab
• caffeic acid phenethyl ester
• CAPE
• oxidative stress
• retinal pigment epithelium

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

This study was supported by Trakya University Scientific Research Fund (Grant No: TUBAP 2015/232).

Additional information

Funding

This study was supported by Trakya University Scientific Research Fund (Grant No: TUBAP 2015/232).