在老化小鼠心律失常症模型中,右心室收缩功能逐渐减少
Emmanuel M Camors1,2, Alyson H Roth1,2, Joseph R Alef1,2
1Heart Institute, Department of Pediatrics, University of Tennessee Health Science Center, Memphis (E.M.C., A.H.R., J.R.A., J.N.J., E.P., J.A.T.).
Circulation
|April 19, 2022
概括
PKP2基因的致病变体导致心律失常症 (ACM). 在ACM早期,右心室肌细胞的活性表达减少导致收缩受损和功能障碍.
科学领域:
- 心血管遗传学
- 分子心脏病学
- 遗传性疾病
背景情况:
- 节律失调性心肌病 (ACM) 是一种遗传性体内疾病.
- PKP2变异是突变阳性ACM的最常见原因.
- 由于离子通道的错误定位和处理的改变,早期的ACM阶段存在心脏突然死亡的风险.
研究的目的:
- 研究PKP2截断变体对ACM肌细胞收缩的影响.
- 使用新的PKP2敲入小鼠模型模仿家族ACM.
- 阐明PKP2变体在ACM病变中的作用.
主要方法:
- 开发了一个PKP2敲入小鼠模型 (PKP2-L404fsX5).
- 进行了串行心声学,心电图和血压测量.
- 进行了组织学,心肌细胞收缩性,细胞内和基因/蛋白质表达分析.
主要成果:
- 在3个月后,Pkp2- Het小鼠呈现出右心室 (RV) 进展性衰竭,左心室功能正常.
- 在Pkp2- Het小鼠中,RV心肌细胞收缩率降低,与RV功能障碍相关.
- 在Pkp2- Het小鼠和ACM患者中观察到VR活性表达的降低和酸化的增加.
结论:
- 减少RV肌细胞的活性表达导致早期ACM的收缩受损.
- 这种动蛋白失调是导致ACM进展性RV功能障碍的关键机制.
- 这些发现突出了与PKP2突变相关的ACM病变的新途径.
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