Heart and Vascular Centre, Semmelweis University, Budapest, Hungary; Department of Cardiac Surgery, University of Halle, Halle, Germany.
Institute of Surgical Research, University of Szeged, Szeged, Hungary.
J Heart Lung Transplant. 2021 Mar;40(3):183-192. doi: 10.1016/j.healun.2020.11.003. Epub 2020 Nov 7.
Maintenance of cell viability during cold storage is a key issue in organ transplantation. Methane (CH) bioactivity has recently been recognized in ischemia/reperfusion conditions; we therefore hypothesized that cold storage in CH-enriched preservation solution can provide an increased defense against organ dysfunction during experimental heart transplantation (HTX).
The hearts of donor Lewis rats were stored for 60 minutes in cold histidine-tryptophan-ketoglutarate (Custodiol [CS]) or CH-saturated CS solution (CS-CH) (n = 12 each). Standard heterotopic HTX was performed, and 60 minutes later, the left ventricular (LV) pressure-volume relationships LV systolic pressure (LVSP), systolic pressure increment (dP/dtmax), diastolic pressure decrement, and coronary blood flow (CBF) were measured. Tissue samples were taken to detect proinflammatory parameters, structural damage (by light microscopy), endoplasmic reticulum (ER) stress, and apoptosis markers (CCAAT/enhancer binding protein [C/EBP] homologous protein, GRP78, glycogen synthase kinase-3β, very low-density lipoprotein receptor, caspase 3 and 9, B-cell lymphoma 2, and bcl-2-like protein 4), whereas mitochondrial functional changes were analyzed by high-resolution respirometry.
LVSP and dP/dtmax increased significantly at the largest pre-load volumes in CS-CH grafts as compared with the CS group (114.5 ± 16.6 mm Hg vs 82.8 ± 4.6 mm Hg and 3,133 ± 430 mm Hg/s vs 1,739 ± 169 mm Hg/s, respectively); the diastolic function and CBF (2.4 ± 0.4 ml/min/g vs 1.3 ± 0.3 ml/min/g) also improved. Mitochondrial oxidative phosphorylation capacity was more preserved (58.5 ± 9.4 pmol/s/ml vs 27.7 ± 6.6 pmol/s/ml), and cytochrome c release was reduced in CS-CH storage. Signs of HTX-caused myocardial damage, level of ER stress, and the transcription of proapoptotic proteins were significantly lower in CS-CH grafts.
The addition of CH during 1 hour of cold storage improved early in vitro graft function and reduced mitochondrial dysfunction and activation of inflammation. Evidence shows that CH reduced ER stress-linked proapoptotic signaling.
在器官移植中，保持细胞活力是冷藏过程中的一个关键问题。最近发现甲烷（CH）在缺血/再灌注条件下具有生物活性；因此，我们假设在富含 CH 的保存液中冷藏可以在实验性心脏移植（HTX）期间增加对器官功能障碍的防御。
供体 Lewis 大鼠的心脏在冷组氨酸-色氨酸-酮戊二酸（Custodiol [CS]）或 CH 饱和 CS 溶液（CS-CH）中冷藏 60 分钟（每组 12 只）。进行标准异位 HTX，60 分钟后测量左心室（LV）压力-容积关系，LV 收缩压（LVSP）、收缩压增量（dP/dtmax）、舒张压下降和冠状动脉血流量（CBF）。取组织样本检测促炎参数、结构损伤（光镜下）、内质网（ER）应激和凋亡标志物（CCAAT/增强子结合蛋白[C/EBP]同源蛋白、GRP78、糖原合酶激酶-3β、极低密度脂蛋白受体、半胱天冬酶 3 和 9、B 细胞淋巴瘤 2 和 bcl-2 样蛋白 4），同时通过高分辨率呼吸测定分析线粒体功能变化。
与 CS 组相比，CS-CH 移植物在最大预加载体积时 LVSP 和 dP/dtmax 显著增加（分别为 114.5 ± 16.6 mm Hg 与 82.8 ± 4.6 mm Hg 和 3133 ± 430 mm Hg/s 与 1739 ± 169 mm Hg/s）；舒张功能和 CBF（2.4 ± 0.4 ml/min/g 与 1.3 ± 0.3 ml/min/g）也有所改善。线粒体氧化磷酸化能力得到更好的保留（58.5 ± 9.4 pmol/s/ml 与 27.7 ± 6.6 pmol/s/ml），并且在 CS-CH 储存过程中细胞色素 c 的释放减少。CS-CH 移植物中与 HTX 引起的心肌损伤、ER 应激水平和促凋亡蛋白转录相关的迹象明显降低。
在 1 小时的冷藏过程中添加 CH 可改善早期体外移植物功能，并减少线粒体功能障碍和炎症激活。证据表明 CH 减少了与 ER 应激相关的促凋亡信号。
