Supplementation of procyanidins B2 attenuates photooxidation-induced apoptosis in ARPE-19 cells

Abstract

During the aging process, dimers of dietary vitamin A accumulated in retinal pigment epithelium (RPE) cells. Vitamin A dimer-mediated photooxidation resulted in RPE apoptosis, which is associated with age-related degenerative disease of retina, leading to blindness. It has been reported that proanthocyanidin-rich grape seed extract reduces oxidative stress in the eye. In this study, we investigated the underlying mechanism of photooxidation-induced apoptosis inhibition by procyanidins B2 (PB2), one of the main components of grape seed proanthocyanidin. To mimic vitamin A dimer-mediated photooxidation, ARPE-19 cells that accumulated vitamin A dimer, A2E, were used as a model system. Exposure of A2E loaded ARPE-19 cells to blue light induced ER stress and resulted in significant apoptosis. Pretreatment of blue light-exposed A2E containing ARPE-19 cells with PB2 inhibited apoptosis, increased the ratio of Bcl-2/Bax in the mitochondria, attenuated ROS and cytochrome c release, and decreased caspase cleavage. Additionally, PB2 inhibited the phosphorylation of ER stress markers elF2α and IRE1α and reduced CHOP expression. Moreover, PB2 inhibition of apoptosis is dependent on the UPR chaperone GRP78, indicating PB2 inhibits vitamin A dimer-mediated apoptosis in RPE cells by activating the UPR.

Oligomeric proanthocyanidins inhibit apoptosis of chondrocytes induced by interleukin-1β

“…Therefore, we found that OPC can inhibit apoptosis by protecting mitochondria. Similar results have been proven in other kinds of cells (39)(40)(41)(42)(43). In this study, we used chondrocytes derived from mice and did not compare with chondrocytes of other animals.…”

Effects of grape seed proanthocyanidin B2 pretreatment on oxidative stress and renal tubular epithelial cell apoptosis after renal ischemia reperfusion in mice

“…Li et al . 36 also showed that the intervention of procyanidins B2 could significantly reduce the apoptosis of ARPE-19 cells induced by photooxidation, increase the proportion of bcl-2/Bax in mitochondria, reduce the release of ROS and cytochrome c, and reduce the caspase cleavage. Li et al .…”

“…The experimental results showed that the grape seed procyanidin B2 pretreatment could significantly reduce the apoptosis of renal tubular epithelial cells in mice and necrosis, and could significantly reduce the cleaved-caspase3 protein expression level; those might be related to grape seed procyanidin B2 pretreatment to enhance the overall antioxidant system in mice, at the same time reduce the ischemia-reperfusion kidney partial oxidative stress injury. Li et al 36 also showed that the intervention of procyanidins B2 could significantly reduce the apoptosis of ARPE-19 cells induced by photooxidation, increase the proportion of bcl-2/Bax in mitochondria, reduce the release of ROS and cytochrome c, and reduce the caspase cleavage. Li et al 37 also found that the antioxidant activity of grape seed proanthocyanidin B2 (GSPB2) and resveratrol inhibited the activation of cytochrome c release, caspase-9 and caspase-3 through the regulation of lactadherin, and had a protective effect on advanced glycation end products induced apoptosis.…”

Selenium Protects against Zearalenone-Induced Oxidative Stress and Apoptosis in the Mouse Kidney by Inhibiting Endoplasmic Reticulum Stress

“…Some exogenous substances, such as heavy metals and mycotoxins, induce endoplasmic reticulum stress and unfolded protein reactions that can result in apoptosis [24,31,33]. Studies have shown that some antioxidants such as resveratrol, procyanidin, and curcumin can inhibit apoptosis through inhibition of ERS [34][35][36]. Therefore, antioxidants can reduce the damage caused by foreign substances to cells by regulating endoplasmic reticulum stress.…”