Circulating Levels of Hypoxia-regulating MicroRNAs in Systemic Lupus Erythematosus Patients with Hemolytic Anemia

Objective MicroRNAs are fine regulators for gene expression during the post-transcriptional stage in many autoimmune diseases.HypoxamiRs(miR-210 and miR-21)play an important role in hypoxia and in inflammation-associated hypoxia.Systemic lupus erythematosus(SLE)is a chronic systemic autoimmune disease that would potentiate many pathological complications,including hemolytic anemia.This study aimed to investigate the role of hypoxamiRs in SLE/hemolytic anemia patients.Methods This work was designed to analyze the circulating levels of↱the miR-210 and miR-21 expressions and hypoxia-inducible factor-1α(HIF-α)in SLE/hemolytic anemia patients.SLE activity was evaluated for all patients by SLE Disease Activity Index(SLEDAI).Clinical manifestations/complications and serological/hematological investigations were reported.HIF-αconcentration was assayed by ELISA and expression of miR-21 and miR-210 was analyzed by qRT-PCR.Results The results indicated that the fold change of the miR-210/miR-21 expressions in plasma was significantly elevated in SLE/hemolytic anemia patients.A strong positive correlation between the miR-210 and miR-21 expression levels was also recorded.Among the associated-disease complications,hypertension,arthritis,oral ulcers,and serositis were associated with a high circulating miR-210 expression,while the occurrence of renal disorders was associated with the increased miR-21 expression.Furthermore,the HIF-αlevel was remarkably elevated in SLE/hemolytic anemia patients.A high positive correlation was recorded between the HIF-αconcentration and miR-210/miR-21 expression levels.The occurrence of oral ulcers,arthritis,and hypertension was associated with the increased HIF-αconcentration.On the other hand,SLEDAI and white blood cell count were positively correlated with miR-21/miR-210.The erythrocyte sedimentation rate was positively correlated with miR-21.Conclusion The dysregulation of the circulating miR-210/miR-210/HIF-1αlevels in SLE/hemolytic anemia patients advocated that the hypoxia pathway might have an essential role in the pathogenesis and complications of these diseases.