Paraskevaidis Ioannis, Kourek Christos, Farmakis Dimitrios, Tsougos Elias
Medical School of Athens, National and Kapodistrian University of Athens, 15772 Athens, Greece.
Department of Cardiology, Hygeia Hospital, 15123 Athens, Greece.
Biomolecules. 2024 Nov 29;14(12):1534. doi: 10.3390/biom14121534.
Myocardial cells and the extracellular matrix achieve their functions through the availability of energy. In fact, the mechanical and electrical properties of the heart are heavily dependent on the balance between energy production and consumption. The energy produced is utilized in various forms, including kinetic, dynamic, and thermal energy. Although total energy remains nearly constant, the contribution of each form changes over time. Thermal energy increases, while dynamic and kinetic energy decrease, ultimately becoming insufficient to adequately support cardiac function. As a result, toxic byproducts, unfolded or misfolded proteins, free radicals, and other harmful substances accumulate within the myocardium. This leads to the failure of crucial processes such as myocardial contraction-relaxation coupling, ion exchange, cell growth, and regulation of apoptosis and necrosis. Consequently, both the micro- and macro-architecture of the heart are altered. Energy production and consumption depend on the heart's metabolic resources and the functional state of the cardiac structure, including cardiomyocytes, non-cardiomyocyte cells, and their metabolic and energetic behavior. Mitochondria, which are intracellular organelles that produce more than 95% of ATP, play a critical role in fulfilling all these requirements. Therefore, it is essential to gain a deeper understanding of their anatomy, function, and homeostatic properties.
心肌细胞和细胞外基质通过能量供应来实现其功能。事实上，心脏的机械和电特性在很大程度上依赖于能量产生与消耗之间的平衡。所产生的能量以各种形式被利用，包括动能、势能和热能。尽管总能量几乎保持恒定，但每种形式的贡献会随时间而变化。热能增加，而势能和动能减少，最终变得不足以充分支持心脏功能。结果，有毒副产物、未折叠或错误折叠的蛋白质、自由基及其他有害物质在心肌内积聚。这导致诸如心肌收缩 - 舒张偶联、离子交换、细胞生长以及细胞凋亡和坏死调节等关键过程的失败。因此，心脏的微观和宏观结构都会发生改变。能量产生和消耗取决于心脏的代谢资源以及心脏结构的功能状态，包括心肌细胞、非心肌细胞及其代谢和能量行为。线粒体作为产生超过95%ATP的细胞内细胞器，在满足所有这些需求方面起着关键作用。因此，深入了解它们的解剖结构、功能和稳态特性至关重要。
