Department of Pharmacy, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Assessment of Clinical Drugs Risk and Individual Application Key Laboratory, Beijing, China.
Eur Rev Med Pharmacol Sci. 2020 Feb;24(3):1367-1377. doi: 10.26355/eurrev_202002_20194.
The role of NEAT1 in cancers has been demonstrated. But the role of NEAT1 in cardiac hypertrophy still remains unknown. This study aimed to elucidate the specific function of long non-coding RNA (lncRNA) NEAT1 in cardiac hypertrophy and its underlying mechanism.
In this study, the in vivo and in vitro cardiac hypertrophy models were constructed by transverse aortic coarctation (TAC) procedure in rats and phenylephrine (PE) induction in primary cardiomyocytes, respectively. The expression levels of NEAT1, microRNA-19a-3p, SMYD2, and cardiac hypertrophic markers were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cardiac hypertrophy was evaluated as calculating the surface area of hypertrophic cardiomyocyte by fluorescein isothiocyanate (FITC)-Phalloidin staining. Luciferase Reporter Gene Assay was conducted to detect the binding of NEAT1, SMYD2, and microRNA-19a-3p.
The results showed that NEAT1 and SMYD2 were highly expressed in myocardium of rats with cardiac hypertrophy and PE-induced primary cardiomyocytes, whereas microRNA-19a-3p was lowly expressed. Besides, NEAT1 overexpression markedly upregulated levels of the cardiac hypertrophic markers. Moreover, FITC-Phalloidin staining also revealed hypertrophic cardiomyocytes overexpressing NEAT1. On the contrary, microRNA-19a-3p overexpression reduced the cardiomyocyte surface area and downregulated the levels of the cardiac hypertrophic markers. As luciferase reporter gene assay demonstrated, NEAT1 and SMYD2 could bind to microRNA-19a-3p. Finally, the gain-of-function experiments were designed to verify whether NEAT1 exerted its functions in cardiac hypertrophy by modulating SMYD2 and microRNA-19a-3p. Furthermore, both microRNA-19a-3p overexpression or SMYD2 knockdown could inhibit and reduce the cardiomyocyte surface area, and downregulate the levels of the cardiac hypertrophic markers.
In summary, NEAT1 promotes the occurrence and progression of cardiac hypertrophy by upregulating SMYD2 by binding to microRNA-19a-3p.
已经证明 NEAT1 在癌症中的作用。但是，NEAT1 在心脏肥大中的作用仍然未知。本研究旨在阐明长链非编码 RNA（lncRNA）NEAT1 在心脏肥大中的特定功能及其潜在机制。
在这项研究中，通过大鼠横主动脉缩窄（TAC）手术和原代心肌细胞中去甲肾上腺素（PE）诱导分别构建体内和体外心脏肥大模型。通过定量实时聚合酶链反应（qRT-PCR）检测 NEAT1、microRNA-19a-3p、SMYD2 和心脏肥大标志物的表达水平。通过荧光素异硫氰酸酯（FITC）-鬼笔环肽染色评估心脏肥大，计算肥大心肌细胞的表面积。荧光素酶报告基因检测用于检测 NEAT1、SMYD2 和 microRNA-19a-3p 的结合。
结果表明，NEAT1 和 SMYD2 在心脏肥大大鼠的心肌和 PE 诱导的原代心肌细胞中高表达，而 microRNA-19a-3p 低表达。此外，NEAT1 过表达显著上调心脏肥大标志物的水平。此外，FITC-鬼笔环肽染色也显示过表达 NEAT1 的肥大心肌细胞。相反，microRNA-19a-3p 过表达减少心肌细胞表面积并下调心脏肥大标志物的水平。正如荧光素酶报告基因检测所示，NEAT1 和 SMYD2 可以与 microRNA-19a-3p 结合。最后，进行了功能获得实验以验证 NEAT1 是否通过调节 SMYD2 和 microRNA-19a-3p 发挥其在心脏肥大中的作用。此外，microRNA-19a-3p 过表达或 SMYD2 敲低均可抑制和减少心肌细胞表面积，并下调心脏肥大标志物的水平。
总之，NEAT1 通过与 microRNA-19a-3p 结合上调 SMYD2 促进心脏肥大的发生和发展。
