Mir204 and Mir211 suppress synovial inflammation and proliferation in rheumatoid arthritis by targeting Ssrp1

Elife. 2022 Dec 13:11:e78085. doi: 10.7554/eLife.78085.

Abstract

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease characterized by synovial hyperplasia. Mir204 and Mir211 are homologous miRNAs with the same gene targeting spectrum. It is known that Mir204/211 play an important role in protecting osteoarthritis development; however, the roles of Mir204/211 in RA disease have not been determined. In the present study, we investigated the effects and molecular mechanisms of Mir204/211 on synovial inflammation and hyperproliferation in RA. The effects of Mir204/211 on the inflammation and abnormal proliferation in primary fibroblast-like synoviocytes (FLSs) were examined by Mir204/211 gain-of-function and loss-of-function approaches in vitro and in vivo. We identified the structure-specific recognition protein 1 (Ssrp1) as a downstream target gene of Mir204/211 based on the bioinformatics analysis. We overexpressed Ssrp1and Mir204/211 in FLS to determine the relationship between Ssrp1 and Mir204/211 and their effects on synovial hyperplasia. We created a collagen-induced arthritis (CIA) model in wild-type as well as Mir204/211 double knockout (dKO) mice to induce RA phenotype and administered adeno-associated virus (AAV)-mediated Ssrp1-shRNA (AAV-shSsrp1) by intra-articular injection into Mir204/211 dKO mice. We found that Mir204/211 attenuated excessive cell proliferation and synovial inflammation in RA. Ssrp1 was the downstream target gene of Mir204/211. Mir204/211 affected synovial proliferation and decelerated RA progression by targeting Ssrp1. CIA mice with Mir204/211 deficiency displayed enhanced synovial hyperplasia and inflammation. RA phenotypes observed in Mir204/211 deficient mice were significantly ameliorated by intra-articular delivery of AAV-shSsrp1, confirming the involvement of Mir204/211-Ssrp1signaling during RA development. In this study, we demonstrated that Mir204/211 antagonize synovial hyperplasia and inflammation in RA by regulation of Ssrp1. Mir204/211 may serve as novel agents to treat RA disease.

Keywords: Ssrp1; cell biology; mir-204/-211; mouse; synovium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arthritis, Experimental* / genetics
  • Arthritis, Experimental* / metabolism
  • Arthritis, Rheumatoid* / genetics
  • Arthritis, Rheumatoid* / metabolism
  • Cell Proliferation
  • Cells, Cultured
  • Fibroblasts / metabolism
  • Hyperplasia / metabolism
  • Inflammation / pathology
  • Mice

Grants and funding

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.