Ye-Rin Heo1, Chang-Nam Son1, Won-Ki Baek2, Sang-Hyon Kim1,3

1Department of Internal Medicine, Division of Rheumatology, Keimyung University School of Medicine, Daegu, Republic of Korea
2Department of Microbiology, Keimyung University School of Medicine, Daegu, Republic of Korea
3Institute for Medical Science, Keimyung University, Daegu, Republic of Korea

Keywords: Apoptosis; autophagy, fibroblast-like synoviocytes, grape seed proanthocyanidin extract, rheumatoid arthritis.

Abstract

Objectives: In this study, we aimed to evaluate the association between grape seed proanthocyanidin extract (GSPE) and rheumatoid arthritis-fibroblast-like synoviocytes (RA-FLSs) and to investigate whether GSPE induces cell death in RA-FLSs.

Materials and methods: The FLSs were isolated from RA synovial tissues. Cell viability and cell cycle staging were analyzed using a hemocytometer and flow cytometry. Caspase 3 and poly (ADP-ribose) polymerase (PARP) proteins were analyzed using Western blotting with z-VAD-fmk. Protein LC3 and polyubiquitin-binding protein p62 that were degraded by autophagy were evaluated using Western blotting with 3-methyladenine and chloroquine. Reactive oxygen species (ROS) were also evaluated.

Results: When RA-FLSs were treated with GSPE, cell viability decreased, the number of cells in sub-G1 and G2/M phases increased, and the expression of pro-PARP and pro-caspase 3 proteins decreased in a concentration-dependent manner. This result was offset, when the cells were co-treated with the pan-caspase inhibitor z-VAD-fmk. The reduced cell viability, increased expression of LC3-II protein, and reduced expression of p62 protein with GSPE treatment were offset, when RA-FLSs were co-treated with GSPE and autophagy inhibitors 3-methyladenine and chloroquine. The level of ROS in RA-FLSs treated with GSPE was significantly lower than treatment with N-acetyl-cysteine, a ROS inhibitor.

Conclusion: Our study results show that GSPE induces apoptotic and autophagic cell death and inhibites reactive oxygen species in RA-FLSs.

Citation: Heo YR, Son CN, Baek WK, Kim SH. Grape seed proanthocyanidin extract induces apoptotic and autophagic cell death in rheumatoid arthritis fibroblast-like synoviocytes. Arch Rheumatol 2022;37(3):393-403.

Ethics Committee Approval

The study protocol was approved by the Institutional Review Board of Keimyung University Dongsan Hospital (No: 2020-01- 055). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Data Sharing Statement:
The data that support the findings of this study are available from the corresponding author upon reasonable request.

Author Contributions

All authors contributed equally to the article.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

This work was funded by the researchpromoting grant from the Keimyung University Dongsan Medical Center in 2019.