Department of Cardiac and Vascular Surgery, University Hospital Berne, Bern, Switzerland.
J Am Coll Cardiol. 2011 Aug 23;58(9):966-73. doi: 10.1016/j.jacc.2011.03.054.
This study investigated the hypothesis whether S100A1 gene therapy can improve pathological key features in human failing ventricular cardiomyocytes (HFCMs).
Depletion of the Ca²⁺-sensor protein S100A1 drives deterioration of cardiac performance toward heart failure (HF) in experimental animal models. Targeted repair of this molecular defect by cardiac-specific S100A1 gene therapy rescued cardiac performance, raising the immanent question of its effects in human failing myocardium.
Enzymatically isolated HFCMs from hearts with severe systolic HF were subjected to S100A1 and control adenoviral gene transfer and contractile performance, calcium handling, signaling, and energy homeostasis were analyzed by video-edge-detection, FURA2-based epifluorescent microscopy, phosphorylation site-specific antibodies, and mitochondrial assays, respectively.
Genetically targeted therapy employing the human S100A1 cDNA normalized decreased S100A1 protein levels in HFCMs, reversed both contractile dysfunction and negative force-frequency relationship, and improved contractile reserve under beta-adrenergic receptor (β-AR) stimulation independent of cAMP-dependent (PKA) and calmodulin-dependent (CaMKII) kinase activity. S100A1 reversed underlying Ca²⁺ handling abnormalities basally and under β-AR stimulation shown by improved SR Ca²⁺ handling, intracellular Ca²⁺ transients, diastolic Ca²⁺ overload, and diminished susceptibility to arrhythmogenic SR Ca²⁺ leak, respectively. Moreover, S100A1 ameliorated compromised mitochondrial function and restored the phosphocreatine/adenosine-triphosphate ratio.
Our results demonstrate for the first time the therapeutic efficacy of genetically reconstituted S100A1 protein levels in HFCMs by reversing pathophysiological features that characterize human failing myocardium. Our findings close a gap in our understanding of S100A1's effects in human cardiomyocytes and strengthen the rationale for future molecular-guided therapy of human HF.
本研究旨在验证 S100A1 基因治疗是否可以改善人类衰竭心肌细胞（HFCM）的病理关键特征。
钙传感器蛋白 S100A1 的耗竭会导致实验动物模型中心脏功能恶化，进而发展为心力衰竭（HF）。心脏特异性 S100A1 基因治疗对这种分子缺陷的靶向修复挽救了心脏功能，这引发了一个内在问题，即其在人类衰竭心肌中的作用。
从严重收缩性 HF 心脏中酶分离的 HFCM 接受 S100A1 和对照腺病毒基因转导，并通过视频边缘检测、基于 FURA2 的荧光显微镜、磷酸化位点特异性抗体和线粒体测定分别分析收缩性能、钙处理、信号转导和能量稳态。
采用人 S100A1 cDNA 的基因靶向治疗使 HFCM 中的 S100A1 蛋白水平正常化，逆转了收缩功能障碍和负力频率关系，并改善了β肾上腺素受体（β-AR）刺激下的收缩储备，而不依赖于 cAMP 依赖性（PKA）和钙调蛋白依赖性（CaMKII）激酶活性。S100A1 逆转了基础和β-AR 刺激下的基本钙处理异常，表现为 SR 钙处理、细胞内钙瞬变、舒张期钙超载和心律失常性 SR 钙渗漏的敏感性降低，分别。此外，S100A1 改善了受损的线粒体功能并恢复了磷酸肌酸/三磷酸腺苷比值。
我们的研究结果首次证明了通过逆转人类衰竭心肌中特征性的病理生理特征，用基因重构的 S100A1 蛋白水平对 HFCM 进行治疗的疗效。我们的发现填补了我们对 S100A1 在人类心肌细胞中作用的理解空白，并为未来人类 HF 的分子指导治疗提供了依据。
