Protective Effects of Blueberry Anthocyanins against H₂O₂-Induced Oxidative Injuries in Human Retinal Pigment Epithelial Cells

Abstract

Blueberry anthocyanins are considered protective of eye health because of their recognized antioxidant properties. In this study, blueberry anthocyanin extract (BAE), malvidin (Mv), malvidin-3-glucoside (Mv-3-glc), and malvidin-3-galactoside (Mv-3-gal) all reduced HO-induced oxidative stress by decreasing the levels of reactive oxygen species and malondialdehyde and increasing the levels of superoxide dismutase, catalase, and glutathione peroxidase in human retinal pigment epithelial cells. BAE and the anthocyanin standards enhanced cell viability from 63.69 ± 3.36 to 86.57 ± 6.92% (BAE), 115.72 ± 23.41% (Mv), 98.15 ± 9.39% (Mv-3-glc), and 127.97 ± 20.09% (Mv-3-gal) and significantly inhibited cell apoptosis (P < 0.01 for all). Mitogen-activated-protein-kinase pathways, including ERK1/2 and p38, were involved in the bioactivities. In addition, the anthocyanins decreased vascular-endothelial-cell-growth-factor levels and activated Akt-signal pathways. These combined results supported the hypothesis that blueberry anthocyanins could inhibit the induction and progression of age-related macular degeneration (AMD) through antioxidant mechanisms.

Bilberry anthocyanin-rich extract protects against retinal photooxidative damage via activation of HO-1 and inhibition of NF-κB

“…In this study, BAE protected RPE cells from visible lightinduced damage and reduced the intracellular ROS levels. A previous study shown that blueberry ACNs protected against H 2 O 2 -induced oxidative injuries in RPE cells (Huang et al, 2018). In addition, quercetin protected retinal cells from H 2 O 2 -and light-induced oxidative stress by inducing the expression of HO-1 (Saviranta et al, 2011;.…”

Antioxidant Blueberry Anthocyanins Induce Vasodilation via PI3K/Akt Signaling Pathway in High-Glucose-Induced Human Umbilical Vein Endothelial Cells

“…Blueberry anthocyanin extract (BAE) was obtained from rabbiteye blueberry fruits harvested by Fujiabian Orchard Picking (Lishui, Nanjing, China) [18]. Malvidin (Mv), malvidin-3-glucose (Mv-3-glc), malvidin-3-galactose (Mv-3-gal), and 3-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide (MTT) were purchased from Sigma Aldrich (Shanghai, China).…”

“…In our previous study, malvidin was also confirmed as the largest anthocyanidin found in Brightwell rabbiteye blueberry (Vaccinium ashei) of Nanjing, mostly as malvidin-3-glucoside (Mv-3-glc) and malvidin-3-galactoside (Mv-3-gal) [17]. We tried to investigate the different bioactivities of blueberry anthocyanin extract as well as its major constituents Mv-3-glc and Mv-3-gal and found they could improve endothelial function by protecting against oxidative stress [18,19]. However, only a few reports are about the vasodilation activities of anthocyanin extract from blueberry fruits [20].…”

Anti-Apoptotic Activity of Anthocyanins has Potential to inhibit Caspase-3 Signaling

“…Black rice anthocyanins also induce cell proliferation and inhibit the apoptosis pathway [23]. Anthocyanin also promotes antiapoptotic effect on the human retinal pigment epithelial cells [24]. However, the mechanism is still unclear.…”