Hsa_circ_0012919 regulates expression of MDA5 by miR-125a-3p in CD4+ T cells of systemic lupus erythematous.

Systemic lupus erythematous (SLE) is an autoimmune disease with production of various autoantibodies directed against various autoantigens. But the research on melanoma differentiation-associated gene 5 (MDA5) in SLE is still scarce. Here we try to elucidate the effect of hsa_circ_0012919 on MDA5 and its potential clinical value in SLE. CD4+ T cells from SLE patients and healthy control subjects were isolated. Expression of hsa_circ_0012919 and MDA5, and methylation level of MDA5 promoter were detected. Then expression and methylation level of MDA5 promoter was examined after transfection of hsa_circ_0012919-targeted siRNA and plasmids. Expression of hsa_circ_0012919 and MDA5 were further confirmed to be significantly higher in CD4+ T cells of SLE patients (p < 0.05), methylation level of MDA5 promoter was significantly lower in CD4+ T cells of SLE patients (p < 0.05), and expression of MDA5 mRNA was correlated with SLE parameters (p < 0.05). Downregulation or overexpression of hsa_circ_0012919 regulated (1) the expression of MDA5 in a dose-dependent manner and (2) the DNA methylation of MDA5 promoter in CD4+ T cells of SLE. Finally, hsa_circ_0012919 could regulate MDA5 by miR-125a-3p. Hsa_circ_0012919 regulated the expression and methylation of MDA5 in the CD4+ T cells of SLE patients, and hsa_circ_0012919 could regulate MDA5 by miR-125a-3p.