在高性心肌病中引起微血管功能障碍的MDM2信号调节
Puneeth Shridhar1,2, Michael S Glennon1, Soumojit Pal1
1Division of Cardiology, Department of Medicine, and Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute (P.S., M.S.G., S.P., C.J.W., E.J.C., P.B., N.C.G., D.B., J.R.B.), University of Pittsburgh School of Medicine and University of Pittsburgh Medical Center, PA.
Circulation
|October 27, 2023
概括
超性心肌病 (HCM) 的微血管功能障碍源于心脏扩大之前的毛细血管生长受损. 向MDM2 (小鼠双分钟2) 蛋白质使路径正常化,防止HCM小鼠模型中的功能障碍.
科学领域:
- 心血管生物学
- 分子心脏病学
- 血管生物学
背景情况:
- 微血管功能障碍是高性心肌病 (HCM) 中心脏重塑的一个标志.
- HCM的发病与瘤基因突变有关,但微血管异常的作用仍在调查中.
- 这项研究探讨了HCM中微血管功能障碍是否是与异常生长有关的主要事件,独立于心室缩.
研究的目的:
- 在HCM中研究微血管功能障碍和心脏缩之间的时间关系.
- 确定HCM中微血管功能障碍的分子机制.
- 确定是否针对特定的分子通路可以预防HCM的微血管功能障碍.
主要方法:
- 在*Mybpc3*和*Myh6*突变HCM小鼠模型中使用多模式成像来追踪微血管功能障碍.
- 采用分子方法来评估蛋白质水平,相互作用和修饰,重点是E3无素连接酶MDM2和HIF转录因子.
- 通过关键分子途径的体内基因和药理学操纵验证的结果.
主要成果:
- 在HCM模型中,微血管功能障碍与发育早期心肌毛细血管生长的减少有关,先于过度缩小.
- MDM2 (小鼠双分钟2) 被确定为HIF1α和HIF2α稳定的关键调节者,影响亲血管性基因表达.
- 在HCM小鼠中,MDM2的遗传或药理降低使HIF水平正常化,并防止微血管功能障碍.
结论:
- 在HCM发育早期,瘤突变会触发心肌细胞MDM2信号.
- 这种早期信号会导致心肌微环境的长期变化.
- 通过MDM2调节HIF通路,为预防HCM相关的微血管功能障碍提供了潜在的治疗点.
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