Wen Ting Hao1, Lu Huang1, Wei Pan2, Yi Le Ren1

1Department of Rheumatology and Immunology, Xuzhou Municipal Hospital Affiliated to Xuzhou Medical University, Xuzhou, China
2Department of Pathogen Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, Jiangsu

Keywords: Inflammation, PTEN/PI3K/AKT, reduced glutathione, rheumatoid arthritis, synovial fibroblasts

Abstract

Objectives: In this study, we aimed to investigate whether glutathione (GSH) could decrease the secretion of reactive oxygen species (ROS), reduce inflammation, and modulate the phosphatase and tensin homolog deleted on chromosome 10/phosphatidylinositol 3-kinase/AKT (PTEN/PI3K/AKT) in synovial fibroblasts (SFs).

Patients and methods: A total of 30 DBA/1J female mice were used in this study. The release of ROS in MH7A cells was examined using a ROS assay kit. The effects of GSH on the messenger ribonucleic acid (mRNA) expression and protein levels of inflammatory cytokines were determined via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) in mouse SFs and MH7A cells, respectively. The PTEN/PI3K/AKT pathway was investigated via Western blotting. The effects of buthionine-sulfoximine (BSO), as an inhibitor of GSH, on these molecules were examined.

Results: The ROS were decreased after GSH treatment, and the mRNA levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, matrix metalloproteinase (MMP)-1, MMP-3, were also significantly inhibited after GSH stimulation. However, the IL-10 levels were enhanced, and GSH increased the expression of PTEN. The GSH suppressed the activation of phosphorylated (p)-PI3K and p-AKT. The supplementation of the BSO restored the activation of PI3K/AKT pathway with a high production of ROS. The levels of TNF-α, IL-1β and IL-6 were also elevated, when the BSO was added.

Conclusion: These findings suggest that GSH can act as an inflammatory suppressor by downregulating the PTEN/PI3K/AKT pathway in MH7A cells. These data indicated a novel function of GSH for improving the inflammation of RA SFs and may help to alleviate the pathological process of RA.

Citation: Hao WT, Huang L, Ren YL, Pan W. Antioxidant glutathione inhibits inflammation in synovial fibroblasts via PTEN/PI3K/AKT pathway: An in vitro study. Arch Rheumatol 2022;37(2):212-222.

Ethics Committee Approval

All experiments in this study were carried out in strict compliance with the recommendations of the Guide for the Care and Use of Laboratory Animals of the Ministry of Health, China. The study protocol was approved by the Laboratory Animal Welfare and Ethics Committee (LAWEC) of Xuzhou Medical University (Xuzhou, China, SCXK (Su) 2015-0009).
Data Sharing Statement: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Author Contributions

Conception and design, analysis data: W.T.H.; Analysis and interpretation of data: L.H.; Final approval of the version tobe published: W.P.; Drafting the article and revisingit: Y.L.R.

Conflict of Interest

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

Financial Disclosure

This study was funded, in part, by the National Natural Science Foundation of China (No. 81871670), the Jiangsu Planned Projects for Postdoctoral Research Funds (No. 2019K063), and the Priority Academic Program Development of Jiangsu Higher Education Institutions. Young crops engineering reserve talent project of Xuzhou Municipal Hospital Affiliated to Xuzhou Medical University (No. QMHB2021004).