Molecular Mechanisms of Oxidative Stress Relief by CAPE in ARPE-19 Cells

• Published in: International journal of molecular sciences Vol. 24; no. 4; p. 3565
• Main Authors: Ren, Changjie, Zhou, Peiran, Zhang, Mingliang, Yu, Zihao, Zhang, Xiaomin, Tombran-Tink, Joyce, Barnstable, Colin J, Li, Xiaorong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.02.2023; MDPI
• Subjects: Analysis; Annexin V; Antioxidants - pharmacology; Apoptosis; Apoptosis - drug effects; ARPE−19 cells; Caffeic acid; Caffeic Acids - pharmacology; CAPE; Cyclic AMP response element-binding protein; Diabetes; Diabetic retinopathy; Gene expression; Genes; Humans; Immediate-early proteins; MAP kinase; Metabolism; Mitochondria; Mitochondrial uncoupling protein 2; Molecular modelling; Oxidative stress; Oxidative Stress - drug effects; Phenylethyl Alcohol - pharmacology; Physiology; Proteins; Reactive Oxygen Species - metabolism; Retina; Stimulation; Transcription activation; UCP2; China; ARPE−19 cells; CAPE; oxidative stress; UCP2
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms24043565

Caffeic acid phenylethyl ester (CAPE) is an antioxidative agent originally derived from propolis. Oxidative stress is a significant pathogenic factor in most retinal diseases. Our previous study revealed that CAPE suppresses mitochondrial ROS production in ARPE-19 cells by regulating UCP2. The present study explores the ability of CAPE to provide longer-term protection to RPE cells and the underlying signal pathways involved. ARPE-19 cells were given CAPE pretreatment followed by t-BHP stimulation. We used in situ live cell staining with CellROX and MitoSOX to measure ROS accumulation; Annexin V-FITC/PI assay to evaluate cell apoptosis; ZO-1 immunostaining to observe tight junction integrity in the cells; RNA-seq to analyze changes in gene expression; q-PCR to validate the RNA-seq data; and Western Blot to examine MAPK signal pathway activation. CAPE significantly reduced both cellular and mitochondria ROS overproduction, restored the loss of ZO-1 expression, and inhibited apoptosis induced by t-BHP stimulation. We also demonstrated that CAPE reverses the overexpression of immediate early genes (IEGs) and activation of the p38-MAPK/CREB signal pathway. Either genetic or chemical deletion of UCP2 largely abolished the protective effects of CAPE. CAPE restrained ROS generation and preserved the tight junction structure of ARPE-19 cells against oxidative stress-induced apoptosis. These effects were mediated via UCP2 regulation of p38/MAPK-CREB-IEGs pathway.