Atrial fibrillation alters the microRNA expression profiles of the left atria of patients with mitral stenosis.
BACKGROUND
Structural changes of the left and right atria associated with atrial fibrillation (AF) in mitral stenosis (MS) patients are well known, and alterations in microRNA (miRNA) expression profiles of the right atria have also been investigated. However, miRNA changes in the left atria still require delineation. This study evaluated alterations in miRNA expression profiles of left atrial tissues from MS patients with AF relative to those with normal sinus rhythm (NSR).


METHODS
Sample tissues from left atrial appendages were obtained from 12 MS patients (6 with AF) during mitral valve replacement surgery. From these tissues, miRNA expression profiles were created and analyzed using a human miRNA microarray. Results were validated via reverse-transcription and quantitative PCR for 5 selected miRNAs. Potential miRNA targets were predicted and their functions and potential pathways analyzed via the miRFocus database.


RESULTS
The expression levels of 22 miRNAs differed between the AF and NSR groups. Relative to NSR patients, in those with AF the expression levels of 45% (10/22) of these miRNAs were significantly higher, while those of the balance (55%, 12/22) were significantly lower. Potential miRNA targets and molecular pathways were identified.


CONCLUSIONS
AF alters the miRNA expression profiles of the left atria of MS patients. These findings may be useful for the biological understanding of AF in MS patients.
Hai
H
Liu
Guang-Xian
GX
Chen
Meng-ya
MY
Liang
Han
H
Qin
Jian
J
Rong
Jian-ping
JP
Yao
Second Department of Cardiac Surgery, First Affiliated Hospital of Sun Yat-Sen University, 58 Zhongshan II Road, Guangzhou 510080, China. wuzhk@mail.sysu.edu.cn.
Zhong-kai
ZK
Wu
D000328:Adult; D020517:Atrial Appendage / Q000737:chemistry*; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation; D053263:Gene Regulatory Networks; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000032:analysis*; D008875:Middle Aged; D008946:Mitral Valve Stenosis / Q000175:diagnosis / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
D035683:MicroRNAs