Circulating microRNAs expression as predictors of clinical response in rheumatoid arthritis patients treated with green tea

Abstract

Rheumatoid arthritis (RA) greatly affects the quality of life, as it causes multiple joint lesions or even joint deformity that result in varying degrees of functional impairment and disability. This study evaluated the correlation between circulating serum miR-125ba and miR-146a expression and clinical response to green tea therapy in RA patients.In total, 100 female RA patients and 50 healthy female controls were enrolled in this study and patients with RA received green tea therapy (5 cups/day; 1230 mg total catechins) for 24 weeks. Real time-PCR analysis was performed to determine miR-146a and miR-125 b levels from isolated peripheral blood mononuclear cells (PBMCs) of controls, and RA patients at baseline, 12 weeks, and 24 weeks of green tea treatment. There was a significant increase in circulating miR-125 b and decrease in miR-146 expression, and these were positively correlated with disease activity measures and pain intensity after 24 weeks of green tea therapy.The potential role of miR-146a and miR-125b in the diagnosis of RA and clinical therapeutic response to green tea was predicted using the analysis of the respective area under the receiver operating characteristic curve (AUC-ROC). Thus the data showed AUC-cut off values (miR-146a; 0.94, miR-125 b; 0.75) were best evaluated for clinical diagnosis of patients with RA, and that AUC-cut off values of 0.72 for miR-146a; and 0.87 for miR-125 b; were the best cut off values respectively reported for the prediction of RA clinical response to green tea therapy. Compared to non-responders, the data showed that miR-146a and miR-125 provide a stronger tendency towards green tea therapy in RA responders at 24 weeks. Our results showed that, miR-146a and miR-125 b expression levels could significantly predict clinical response to green tea therapy for 24 weeks in 65 % of RA patients. Changes in miR-146a and miR-125b levels after green tea therapy may result from the joint protective, antioxidant, and anti-inflammatory action of green tea. Both miR-146a and miR-125b could be used as diagnostic, therapeutic, and predictive biomarkers in green treatment and may have potential application in related non-drug RA therapy.