Tachampa Kittipong, Wongtawan Tuempong
Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Henri-Dunant Rd, Pathumwan, Bangkok, 10330, Thailand.
Akkhraratchakumari Veterinary College, Walailak University, Tha Sala, Nakhon Si Thammarat, 80160, Thailand.
Vet World. 2020 Aug;13(8):1697-1708. doi: 10.14202/vetworld.2020.1697-1708. Epub 2020 Aug 26.
Cardiac fibroblasts are important for both normal and pathological states of the heart, but the knowledge in cell physiology and genomics is still poorly understood. The aims of the present study were; first, to investigate the expression of cardiac and fibrotic genes in rat cardiac fibroblasts compared to cardiomyocytes and other fibroblasts (skin and muscle fibroblasts), second, to examine the in vitro effect of serum concentration on fibroblast gene expression. The findings can potentially be applied in ischemia/reperfusion models.
Rat cardiac fibroblasts were collected and cultured in different conditions, and their gene expression (21 cardiogenic genes and 16 fibrotic genes) was compared with cardiomyocytes and other fibroblasts using comparative quantitative polymerase chain reaction. We also mimicked myocardial ischemia/reperfusion by depleting and then adding a serum into the culture in conventional culture (10% serum).
Cardiac fibroblasts expressed most of the cardiogenic genes, but their expression levels were significantly lower than in cardiomyocytes, while almost all fibrotic genes in the cardiac fibroblasts were significantly more highly expressed than in cardiomyocytes, except matrix metallopeptidase 9 (Mmp9) which also had greater expression in other fibroblasts. After mimicking cardiac ischemia and reperfusion in vitro by starving and then adding a serum into the cardiac fibroblast culture, the results revealed that Mmp9 expression was significantly increased (>30 times) after increasing but not reducing the serum in the culture. The expression of most cardiogenic and fibrotic genes in cardiac fibroblasts tended to decrease after increasing the serum in the culture. These changes were specific to cardiac fibroblasts but no other fibroblasts.
Cardiac fibroblasts have a distinct pattern of gene expression from other fibroblasts and cardiomyocytes. They are also sensitive to high serum concentration but not affected by serum depletion, suggesting that the process of developing cardiac fibrosis might be stimulated by reperfusion or overcirculation rather than ischemia. The cell starvation followed the adding of serum may serve as a useful model to study cardiac fibrosis cause by the change of blood flow.
心脏成纤维细胞对心脏的正常和病理状态均至关重要，但在细胞生理学和基因组学方面的认知仍十分有限。本研究的目的如下：其一，与心肌细胞及其他成纤维细胞（皮肤和肌肉成纤维细胞）相比，探究大鼠心脏成纤维细胞中心脏及纤维化相关基因的表达情况；其二，检测血清浓度对成纤维细胞基因表达的体外影响。这些研究结果可能应用于缺血/再灌注模型。
收集大鼠心脏成纤维细胞并在不同条件下进行培养，通过比较定量聚合酶链反应，将其基因表达（21个心脏发生相关基因和16个纤维化相关基因）与心肌细胞及其他成纤维细胞进行比较。我们还通过在常规培养（10%血清）中先去除血清然后再添加血清的方式模拟心肌缺血/再灌注。
心脏成纤维细胞表达了大多数心脏发生相关基因，但其表达水平显著低于心肌细胞，而心脏成纤维细胞中几乎所有纤维化相关基因的表达均显著高于心肌细胞，除基质金属蛋白酶9（Mmp9）在其他成纤维细胞中也有较高表达。在体外通过饥饿然后向心脏成纤维细胞培养物中添加血清模拟心脏缺血和再灌注后，结果显示在培养物中增加而非降低血清后，Mmp9表达显著增加（>30倍）。在培养物中增加血清后，心脏成纤维细胞中大多数心脏发生相关和纤维化相关基因的表达趋于下降。这些变化是心脏成纤维细胞所特有的，其他成纤维细胞则无此现象。
心脏成纤维细胞具有与其他成纤维细胞及心肌细胞不同的基因表达模式。它们对高血清浓度敏感，但不受血清去除的影响，这表明心脏纤维化的发展过程可能是由再灌注或过度循环而非缺血所刺激。先细胞饥饿再添加血清的方法可作为研究血流变化导致心脏纤维化的有用模型。
