Hoebart Clara, Kiss Attila, Podesser Bruno K, Tahir Ammar, Fischer Michael J M, Heber Stefan
Institute of Physiology, Center for Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria.
Center for Biomedical Research and Translational Surgery, Medical University of Vienna, 1090 Vienna, Austria.
Biomedicines. 2024 Aug 15;12(8):1856. doi: 10.3390/biomedicines12081856.
Sensory neurons densely innervate the myocardium. The role of their sensing and response to acute and prolonged ischemia is largely unclear. In a cellular model of ischemia-reperfusion injury, the presence of sensory neurons increases cardiomyocyte survival. Here, after the exclusion of classical neurotransmitter release, and measurement of cytokine release, we modified the experiment from a direct co-culture of primary murine cardiomyocytes and sensory neurons to a transfer of the supernatant. Sensory neurons were exposed to ischemia and the resulting conditioned supernatant was transferred onto cardiomyocytes. This approach largely increased the tolerance of cardiomyocytes to ischemia and reperfusion. Towards the identification of the mechanism, it was demonstrated that after ten-fold dilution, the conditioned solution lost its protective effect. The effect remained after removal of extracellular vesicles by ultracentrifugation, and was not affected by exposure to protease activity, and fractionation pointed towards a hydrophilic agent. Solutions conditioned by HEK293t cells or 3T3 fibroblasts also increase cardiomyocyte survival, but to a lower degree. A metabolomic search identified 64 at least two-fold changed metabolites and lipids. Many of these could be identified and are involved in essential cellular functions. In the presented model for ischemia-reperfusion, sensory neurons secrete one or more cardioprotective substances that can improve cardiomyocyte survival.
感觉神经元密集地支配心肌。它们对急性和持续性缺血的感知及反应作用在很大程度上尚不清楚。在缺血再灌注损伤的细胞模型中，感觉神经元的存在可提高心肌细胞的存活率。在此，在排除经典神经递质释放并测量细胞因子释放后，我们将实验从原代小鼠心肌细胞和感觉神经元的直接共培养改为上清液转移。将感觉神经元暴露于缺血环境，然后将产生的条件上清液转移到心肌细胞上。这种方法在很大程度上提高了心肌细胞对缺血和再灌注的耐受性。为了确定其机制，结果表明，在进行十倍稀释后，条件溶液失去了其保护作用。通过超速离心去除细胞外囊泡后，该作用仍然存在，并且不受蛋白酶活性暴露的影响，分级分离指向一种亲水性物质。由HEK293t细胞或3T3成纤维细胞产生的条件溶液也能提高心肌细胞的存活率，但程度较低。代谢组学研究确定了64种至少有两倍变化的代谢物和脂质。其中许多物质可以被识别，并且参与基本的细胞功能。在本文提出的缺血再灌注模型中，感觉神经元分泌一种或多种心脏保护物质，可提高心肌细胞的存活率。
