Targeting Angiogenesis and Visual Cycle in Age-Related Macular Degeneration: The Role of Stem Cells and Vinpocetine

TL;DR

This study explores how bone marrow stem cells and vinpocetine may help treat age-related macular degeneration by reducing harmful effects of amyloid-beta on eye cells.

Contribution

The study introduces a novel combination of bone marrow stem cells and vinpocetine to counter Aβ-induced AMD-related changes in RPE cells.

Findings

Aβ1-42 reduced cell viability in RPE cells, which was restored by all treatments.

VEGF-A upregulation caused by Aβ1-42 was significantly reduced by all treatments.

Combination therapy showed the strongest enhancement of PEDF expression.

Abstract

Purpose

The purpose of this study was to evaluate whether bone marrow stem cells (BMSCs), vinpocetine, or their combination can attenuate amyloid-β (Aβ)-induced alterations in angiogenesis and visual cycle gene expression in a cellular model of age-related macular degeneration (AMD).

Methods

Human retinal pigment epithelium (RPE) cells (ARPE-19) were exposed to Aβ 1-42 for 24h and divided into four groups: (i) co-culture with BMSCs, (ii) treated with vinpocetine, (iii) treated with BMSCs and vinpocetine, and (iv) untreated control. Cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to evaluate the mRNA expression levels of angiogenesis-related genes, vascular endothelial growth factor (VEGF-A) and pigment epithelium-derived factor (PEDF), and RPE-associated visual cycle genes: lecithin retinol acyltransferase (LRAT), retinoid isomerohydrolase (RPE65), retinol dehydrogenase 5 (RDH5), retinol dehydrogenase 10 (RDH10), and retinaldehyde-binding protein 1 (RLPB1).

Results

Aβ1-42 significantly reduced ARPE-19 cell viability (p=0.002); all treatments significantly restored viability. Aβ1-42 upregulated VEGF-A expression, which was significantly downregulated by all treatments. Although Aβ1-42 slightly increased PEDF expression, all treatments significantly enhanced its upregulation, with the combination therapy showing the greatest effect (p=0.006, 0.010, and 0.002, respectively). Furthermore, Aβ 1-42 induced upregulation of most visual cycle genes was reversed by all treatments.

Conclusion

Aβ1-42 induces cytotoxicity, angiogenesis, and dysregulation of visual cycle genes in RPE cells in vitro. BMSCs, vinpocetine, and their combination attenuate these effects, supporting a potential role in AMD therapy pending further investigation.

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