Serum-derived exosomes containing NEAT1 promote the occurrence of rheumatoid arthritis through regulation of miR-144-3p/ROCK2 axis.

Evidence has demonstrated that non-coding RNAs (ncRNAs) could be delivered efficiently to recipient cells using exosomes as a carrier. Additionally, long ncRNA nuclear enriched abundant transcript 1 (NEAT1) is emerging as a vital regulatory molecule in the progression of rheumatoid arthritis (RA). The aim of this study was to identify the NEAT1/miR-144-3p/Rho-associated protein kinase 2 (ROCK2) functional network regulating the WNT signaling pathway in RA. In vivo, a collagen-induced arthritis (CIA) model was established to analyze the effects of blood exosomes on the incidence, clinical score, and bone degradation of RA. In vitro, the CD4+T cells were characterized by flow cytometry and the cell activities were analyzed in the presence of exosome treatment alone or in combination with altered expression of NEAT1, miR-144-3p or Rho-associated protein kinase 2 (ROCK2). The expression of NEAT1, miR-144-3p, ROCK2, and corresponding proteins in the WNT signaling pathway was detected by RT-qPCR and western blot techniques. The binding profile of NEAT1 to miR-144-3p was evaluated via a combination approach of luciferase activity assay, RNA immunoprecipitation, and RNA pull-down experiments. Blood exosomes extracted from RA patients increased the incidence of RA and bone destruction significantly. Overexpression of NEAT1 or ROCK2 promoted immune cell (CD4+T cells) proliferation, Th17 cell differentiation, and cell migration in response to stimulus, whereas knockout of the NEAT1 gene induced the expression of miR-144-3p in CD4+T cells. ROCK2 exogenous expression inhibited the expression of miR-144-3p, inducing activation of the WNT signaling pathway. A novel regulatory pathway NEAT1/miR-144-3p/ROCK2/WNT in RA was investigated as a potential target for RA therapy.