First Department of Geriatric Cardiology, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853, China.
J Geriatr Cardiol. 2012 Sep;9(3):269-77. doi: 10.3724/SP.J.1263.2012.05299.
Previous studies showed that overexpression of sarco-endoplasmic reticulum calcium ATPase (SERCA2a) in a variety of heart failure (HF) models was associated with greatly enhanced cardiac performance. However, it still undefined the effect of SERCA2a overexpression on the systemic inflammatory response and neuro-hormonal factors.
A rapid right ventricular pacing model of experimental HF was used in beagles. Then the animals underwent recombinant adeno-associated virus 1 (rAAV1) mediated gene transfection by direct intra-myocardium injection. HF animals were randomized to receive the SERCA2a gene, enhanced green fluorescent protein (control) gene, or equivalent phosphate buffered saline. Thirty days after gene delivery, the cardiac function was evaluated by echocardiographic testing. The protein level of SERCA2a was measured by western blotting. The proteomic analysis of left ventricular (LV) sample was determined using two-dimensional (2-D) gel electrophoresis and MALDI-TOF-MS. The serum levels of the systemic inflammatory and neuro-hormonal factors were assayed using radioimmunoassay kits.
The cardiac function improved after SERCA- 2a gene transfer due to the significantly increased SERCA2a protein level. Beagles treated with SERCA2a had significantly decreased serum levels of the inflammatory markers (interleukin-6 and tumor necrosis factor-α) and neuro-hormonal factors (brain natriuretic peptide, endothelin-1 and angiotensin II) compared with HF animals. The myocardial proteomic analysis showed that haptoglobin heavy chain, heat shock protein (alpha-crystallin-related, B6) were down-regulated, and galectin-1 was up-regulated in SERCA2a group compared with HF group, companied by up-regulated contractile proteins and NADH dehydrogenase.
These findings demonstrate that regional intramyocardial injections of rAAV1-SERCA2a vectors may improve global LV function, correlating with reverse activation of the systemic inflammatory, excessive neuroendocrine factors and the stress-associated myocardial proteins, suggesting that the beneficial effects of SERCA2a gene transfer may involve the attenuation of stress-associated reaction.
先前的研究表明，在多种心力衰竭（HF）模型中肌浆内质网钙 ATP 酶（SERCA2a）的过度表达与心脏功能的极大改善有关。然而，SERCA2a 过度表达对全身炎症反应和神经激素因素的影响仍不明确。
在比格犬中使用快速右心室起搏模型来建立实验性 HF。然后，通过直接心肌内注射，用重组腺相关病毒 1（rAAV1）介导的基因转染。HF 动物被随机分为接受 SERCA2a 基因、增强型绿色荧光蛋白（对照）基因或等量磷酸盐缓冲盐水。基因传递 30 天后，通过超声心动图检查评估心功能。通过 Western blot 测定 SERCA2a 蛋白水平。使用二维（2-D）凝胶电泳和 MALDI-TOF-MS 测定左心室（LV）样本的蛋白质组分析。使用放射免疫试剂盒测定血清中全身炎症和神经激素因子的水平。
由于 SERCA2a 蛋白水平的显著增加，SERCA-2a 基因转移后心脏功能得到改善。与 HF 动物相比，用 SERCA2a 治疗的比格犬血清中炎症标志物（白细胞介素-6 和肿瘤坏死因子-α）和神经激素因子（脑钠肽、内皮素-1 和血管紧张素 II）水平显著降低。心肌蛋白质组分析显示，与 HF 组相比，SERCA2a 组的结合珠蛋白重链、热休克蛋白（alpha-crystallin-related，B6）下调，半乳糖凝集素-1 上调，同时收缩蛋白和 NADH 脱氢酶上调。
这些发现表明，rAAV1-SERCA2a 载体的局部心肌内注射可能改善整体 LV 功能，与全身炎症反应、神经内分泌过度激活以及应激相关心肌蛋白相关，提示 SERCA2a 基因转移的有益作用可能涉及减轻应激相关反应。
