Study On Plasma MicroRNA-21 In Patients With Alone Atrial Fibrillation

Purpose:Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice,Since lone atrial fibrillation(LAF) without structural heart lesions, related studies are slightly rare. Atrial fibrosis is a hallmark of the AF substrate in patients with lone atrial fibrillation.microRNA-21 (miRNA-21), a newly discovered miRNAs, is closely related with cardiac structural remodeling. But, the study of the expression and significance of miRNA-21 in the plasma of alone atrial fibrillation has not been reported. The purpose of this study was to identify circulating miRNA-21 in human plasma, and finally provide evidence miRNA-21 as a biomarker and therapeutic target for atrial fibrillation.Methods:The experiment involved in 50 patients who admitted the 1st affiliated hospital of Xiamen University from June 2013 to January 2015. The 50 patients were divided into 2 groups,one was lone atrial fibrillation group (27 patients) and the other was from Health Evaluation Center as control (23 patients).lone atrial fibrillation group was divided into two subgroups, persistent atrial fibrillation group and paroxymal atrial fibrillation group. Venous blood was collected from each case of group and healthy control. After that, plasma was collected from the centrifuged blood and saved in-80 ℃ refrigerator. Total RNAs were extracted from each plasma sample. After reverse transcription, the levels of miRNA-21 were detected by qRT-PCR technique. Datas were analyzed by using SPSS18.0 software.Results:qRT-PCR could detect the expression of miRNA-21 in human plasma. Increased expression levels of miRNA-21 were observed in LAF group comparing with controls healthy control(1.88±0.77 vs 1.13±0.57) (P<0.01);the expression of miRNA-21 between persistent atrial fibrillation and paroxymal atrial fibrillation exist significant differences(2.19±0.76 vs 1.49±0.61)(P<0.001). The expression of miRNA-21 between paroxymal atrial fibrillation and healthy control do not exist significant differences yet (P<0.05).Conclusions:1.The plasma miRN A-21 level in patients with LAF was elevated, it suggests that miRNA-21 involves in the development and progress of AF; 2.Compared to patients with paroxymal atrial fibrillation,the plasma miRNA-21 level in patients with ersistent atrial fibrillation was elevated,the expression of miRNA -21 closely related with the severity of the onset of AF;3.The plasma concentration of miRNA-21 may be a useful biomarker in the classification and risk stratification of LAF in humans.