JPH2基因在二尖瓣疾病合并持续性房颤中的表达

JPH2 gene expression in persistent atrial fibrillation with mitral valve disease

目的：探讨连接蛋白-2（JPH2）基因表达水平与二尖瓣疾病合并持续性房颤的关系以及分子机制。方法34例接受二尖瓣手术治疗的患者，根据术前心律分为两组：房颤组18例，为房颤心律患者；对照组16例，为窦性心律患者。所有二尖瓣手术均采用房间沟入路，取房间沟处左心房组织作心房组织样本。利用蛋白质免疫印迹（ Wester blot ）技术和实时定量逆转录聚合酶链反应（ RT-PCR）技术分别分析JPH2蛋白和mRNA的表达变化，分析miRNA-24在其中的作用。结果与对照组相比，房颤组左心房组织JPH2蛋白表达明显下降（0.94±0.29对1.53±0.61，P＜0.01）；两组JPH2基因mRNA表达水平差异无统计学意义（1.76±1.38对1.15±0.94，P＞0.05）。房颤组患者左心房组织miRNA-24表达显著升高（4.49±4.30对1.72±1.08，P＜0.05）。两组在性别、年龄、左心室射血分数以及心功能分级上并无差别，但房颤组患者左心房内径明显扩大（P＝0.02）。结论房颤时心房细胞JPH2蛋白表达水平明显下降，调控其表达的miRNA-24水平明显增加，这可能是房颤发病的分子机制之一，可致房颤心房重构及收缩功能受损。

Objective This research is to explore the Junctophilin-2 （ JPH2 ） expression in persistent atrial fibrillation with mitral valve disease.Methods The left atrial tissue samples were taken from 34 patients with mitral valve disease who underwent cardiac surgery.16 patients were in sinus rhythm, 18 patients had persistent atrial fibrillation.Western blot tech-nique was used to test the JPH2 expression, and the RT-PCR method was used to test the JPH2 gene expression.Results The Westernblot results showed JPH2 expression down-regulated in persistent atrial fibrillation group （0.94 ±0.29 vs.1.53 ± 0.61,P〈0.01）.However, there was no difference with JPH2 mRNA expression between atrial fibrillation patients and sinus rhythm patients（1.76 ±1.38 vs.1.15 ±0.94, P〉0.05）.Expression of miRNA-24 was significantly up-regulated in patients with persistent atrial fibrillation（4.49 ±4.30 vs.1.72 ±1.08, P〈0.05）.There was no significant difference in mean age, gender, ejection fraction and NYHA among the two groups.But the left atrial diameter was significant larger in patients with persistent atrial fibrillation compared to those in sinus rhythm（P=0.02）.Conclusion Junctophilin-2 protein down-regulation may be associated with atrial fibrillation , cause left atrial remodeling and contraction dysfunction .