Epigenetic regulator UHRF1 suppressively organize multiple pathogenesis in rheumatoid arthritis [MBD-seq]

Rheumatoid arthritis (RA) is characterized by chronic synovial inflammation with aberrant epigenetic alterations, leading joint destruction. However, epigenetic regulatory mechanisms underlying RA pathogenesis remain largely unknown. Here we showed that Ubiquitin-like containing PHD and RING finger domains 1 (known as UHRF1) is a central epigenetic regulator to suppressively orchestrate the expression of multiple exacerbation factors in RA. We found remarkable up-regulation of Uhrf1, which is known as a key molecular for maintenance of DNA methylation during cell division 1-3, in murine arthritis tissue, especially synovial fibroblasts (SF). SF-specific Uhrf1 conditional knockout mice indicated more severe arthritic phenotypes with apoptosis resistant SF. Integrative analysis between transcriptome and methylome showed that expression of several cytokines including Ccl20 were up-regulated in Uhrf1-deficient SF. In RA patients, disease activity scores, CCL20 expression, Th17 accumulation, apoptosis resistance were negatively correlated with UHRF1 expression in synovium. Finally, stabilization of UHRF1 by administration of Ryuvidine improved pathogenesis of arthritis model mice. Our results demonstrated that UHRF1 expressed in SF contributes to suppressively orchestrate expression of genes of multiple exacerbating factors under RA progression. Targeting UHRF1 could provide a novel therapeutic strategy for RA. Overall design: DNA methylation profiles of primary synovial fibroblasts obtained from Control and cKO mice were analyzed using MBD2 mediated methylated DNA enrichment followed by next generation sequencing (MBD-seq) with Illumina MiSeq.