小RNA——肥厚型心肌病治疗新展望

肥厚型心肌病(HCM)是指在无明显阻力及容量负荷增加的情况下心肌发生肥厚,通常表现为室间隔非对称肥厚.近几年,随着分子生物学技术的进展,通过基因治疗弛缓心肌肥厚正成为临床研究和实验心脏学的热门研究课题.国内外研究证实,siRNA和miRNA在心肌肥厚形成过程中起着重要的基因调控作用,为HCM的治疗提供了新思路.本文就小RNA(small RNA)分子的发现、作用机制及其对心肌肥厚的治疗作一简要概述和展望.     

心脏β-肌球蛋白重链1382位氨基酸不同突变导致肥厚型心肌病表型研究

目的观察肥厚型心肌病(HCM)致病基因突变导致同一位点氨基酸不同改变的临床表型变化特点,为遗传型-表型关系研究积累数据。方法在529例HCM患者以及307名健康对照者中进行β-肌球蛋白重链基因(MYH7)目标区域靶向捕获再测序筛查,发现的基因变异性Sanger法测序验证。。结果在1例HCM患者中首次发现MYH7基因29号外显子第4145位碱基由G转换为A,结果导致1382位的精氨酸(Arg,R)转变为谷氨酰胺(Gln, Q),另1例HCM患者,29号外显子第4144位碱基由C转换为T,结果导致1382位的精氨酸(Arg,R)转变为色氨酸(Trp, W),正常对照组相同位置1382位表达为精氨酸(Arg,R)。MYH71382位氨基酸发生改变的两例HCM患者临床表型均为肥厚型梗阻性心肌病,并且均在住院期间接受了经皮室间隔心肌消融术治疗,长期随访预后良好。结论首次在中国人HCM患者中发现MYH7基因Arg1382Gln突变,该位点氨基酸发生不同改变后具有相似的临床表型,表现为肥厚型梗阻性心肌病、经室间隔心肌消融术治疗效果好。提示一旦发现该位点基因突变就有可能实现临床表型预测。     

心电图在肥厚型心肌病诊治中的研究进展

肥厚型心肌病是一种以左心室肥厚为特征的遗传性心肌疾病，心电图是肥厚型心肌病初步诊断的重要工具。心电图异常多见于显性肥厚型心肌病基因携带者，且心电图改变较超声心动图检测的左室壁增厚更早、更敏感。现就心电图在HCM诊断和治疗中的研究进展做一综述。     

转录因子KLF2和KLF4调控人血管内皮细胞血管稳态相关基因表达的特征

[目的] Krüppel样因子(KLF)2和4是与血管稳态密切相关的两个核心转录因子,具有抗炎、抗钙化、抗血栓等多重保护效应。本研究旨在在内皮细胞中阐明并验证KLF2和KLF4共同调控的血管稳态相关基因谱。[方法]使用腺病毒(Ad-KLF2或Ad-KLF4)及对照病毒(Ad-NC)处理人脐静脉内皮细胞(HUVEC)24 h后提取RNA并进行转录组测序分析。过表达KLF2和KLF4的测序结果与已报道的KLF2/KLF4双基因敲除鼠测序结果进行叠加。筛选出的差异表达基因通过实时荧光定量PCR在Ad-KLF2或Ad-KLF4处理的HUVEC以及在阿托伐他汀或白藜芦醇处理的HUVEC中进行验证。[结果]转录组学叠加发现,KLF2和KLF4上调的差异基因有256个,KEGG通路富集分析显示这些差异基因主要富集于肥厚型心肌病、扩张型心肌病、ECM-受体交互以及黏着斑、致心律失常性右心室心肌病等;KLF2和KLF4下调的差异基因有145个,KEGG通路富集分析显示这些差异基因主要富集于癌症中的microRNA、糖胺聚糖生物合成-硫酸软骨素/硫酸皮聚糖、矿物质吸收、p53信号通路以及氨基酸生物合成等。...     

肥厚型心肌病并发症的临床观察与护理

肥厚型心肌病（HCM）也称为特发性肥厚主动脉瓣下狭窄（ISS）和肌性主动脉瓣下狭窄,HCM表现为室间隔心肌与血流动力学负荷不成比例的肥厚造成主动脉瓣下压力阶差变化,HCM诊断一定要除外瓣膜疾病与高血压等引起的左室负荷增加的疾病,有家族遗传史的倾向,肥厚型心肌病是心脑血管的一种,常发生在中、老年,易发生猝死,对其住院患者治疗特别是护理观察对其愈后有重要意义。     

肥厚型心肌病相关基因的生物信息学分析

目的筛查肥厚型心肌病相关的关键基因,为肥厚型心肌病的发病机制提供理论依据。方法从高通量基因表达(GEO)数据库中检索包含106例肥厚型心肌病样本及39例对照组样本的高通量测序数据集GSE36961。利用R软件筛选肥厚型心肌病组织和正常组织间差异表达的基因,通过WGCNA构建差异基因的加权重共表达网络,筛选出与肥厚型心肌病相关的模块,对模块中的基因行功能富集分析,并应用STRING数据库构建蛋白互作网络筛选出关键基因。结果从数据集中筛选出8002个差异表达基因(P<0.05),通过WGCNA构建出差异基因的加权重共表达网络,筛选出两个与肥厚型心肌病相关的模块:青色模块(Pearson cor=0.77,P=4e-29)和紫红色模块(Pearson cor=0.76,P=2e-28)。前者基因功能主要富集在能量代谢,后者基因功能主要富集在血管形成。通过蛋白质相互作用网络分析获得32个基因及157个互作关系,从中筛选出与肥厚型心肌病相关的关键基因,提示肥厚型心肌病可能与炎症反应相关。结论本研究通过系统性分析肥厚型心肌病患者的高通量测序数据集,筛选出可能与肥厚型心肌病有关的目标基因32个,再筛选出关键基因10个,其中甲酰肽受体2(formyl peptide receptor 2,FPR2)、毒蕈碱型胆碱受体M2(cholinergic receptor musca⁃rinic 2,CHRM2)与心肌炎症反应相关,余基因的作用仍需在未来的细胞及动物实验中得到进一步的验证。     

肥厚型心肌病临床诊疗新进展

肥厚型心肌病(hypertrophic cardiomyopathy,HCM)是一种常见的典型常染色体显性遗传的心肌病,临床外显率可变,成人多数由1/12的心脏肌节蛋白基因突变引起。其病理改变以心室肌肥厚为主,主要累及左心室和室间隔,大多是非对称性的左心室肥厚,以室间隔肥厚最为显著且伴有左心室流出道狭窄,属梗阻性肥厚型心肌病     

伴高血压的肥厚型心肌病12例临床特点分析

肥厚型心肌病（HCM）是以左心室或右心室肥厚为特征,常为不对称心室肥厚并累及室间隔,心腔缩小,左心室血液充盈受阻、舒张期顺应性下降为基本病态的心肌病。但伴随高血压的肥厚型心肌病,因其与原发性肥厚型心肌病及高血压性心肌肥厚有不同的临床特点,近年已引起人们的重视。本研究回顾分析4年来检出的12例伴高血压的肥厚型心肌病患者资料,旨在提高对本病的认识。     

心脏型肌球蛋白结合蛋白C基因c.2469-3_-4insAG和c.2469-5_-6insT突变与肥厚型心肌病的关系

目的 研究中国人群肥厚型心肌病(Hypertrophic cardiomyopathy,HCM)患者的致病基因突变位点,为遗传咨询提供证据。方法 对HCM先证者行26个HCM相关基因全部外显子及邻近区靶向高通量测序,对基因突变家系成员和80名健康志愿者行Sanger测序,以验证基因突变位点。采集分析HCM患者及其家系成员临床症状、体征、超声心动图、心电图等信息。结果 该家系两名成员的心脏型肌球蛋白结合蛋白C基因（cardiac myosin binding protein-C3,MYBPC3）内含子区域中均同时携带c.2469-3_-4insAG和c.2469-5_-6insT两个插入突变,该家系其余成员及80名健康志愿者中未检出异常突变基因。两名基因突变携带者均为HCM患者,且发病年龄晚,有心慌、胸闷症状,心脏超声提示室间隔肥厚。结论 基因突变功能预测,提示MYBPC3 c.2469-3_-4insAG和c.2469-5_-6insT基因突变可引起蛋白特性及剪接位点的改变,可能是家族性肥厚型心肌病的致病突变位点。     

肥厚型心肌病的治疗现状

肥厚型心肌病(HCM)以心肌非对称性肥厚、心腔变小为特征,以左室血流充盈受阻,左心室舒张期顺应性下降为基本病态原因不明的心肌病.在HCM患者中约25%存在左室流出道梗阻称为肥厚梗阻型心肌病(HOCM).通常HOCM最大肥厚部位位于室间隔基底部,同时伴有其他组织异常,包括二尖瓣瓣叶延长增大、异常的冠状动脉和胶原基质.本文对HCM的治疗现状作一综述.     

Amyloid heart disease mimicking hypertrophic cardiomyopathy

OBJECTIVE: To investigate the importance of transthyretin (TTR) gene mutations in explaining the phenotypic expression in patients diagnosed with hypertrophic cardiomyopathy (HCM) in northern Sweden. BACKGROUND: Hypertrophic cardiomyopathy is relatively common and often caused by mutations in sarcomeric protein genes. Mutations in the TTR gene are also common, one of which causes familial amyloid polyneuropathy (FAP), with peripheral polyneuropathy and frequently, cardiac hypertrophy. These circumstances were highlighted by the finding of an index case with amyloidosis, presenting itself as HCM. Initial rectal and fat biopsies did not show amyloid deposits. Later on, the patient was shown to carry a TTR gene mutation, and cardiac amyloidosis was confirmed by myocardial biopsy. Only then was a repeated fat biopsy positive for amyloid deposits. DESIGN: Cross-sectional study. SETTING: Cardiology tertiary referral centre. SUBJECTS: Forty-six unrelated individuals with HCM and the index case were included. Common diagnostic criteria for HCM were used. The 46 patients with HCM were previously analysed for mutations in eight sarcomeric protein genes and the TTR gene was now analysed by denaturing high-performance liquid chromatography and direct sequencing. RESULTS: One mutation in the TTR gene (Val30Met) was found in three individuals and the index case. CONCLUSIONS: Three of the 46 cases with HCM carried the Val30Met mutation, and were considered likely to have cardiac amyloidosis, like the index case. As a correct diagnosis of cardiac amyloidosis is mandatory for a potentially life-saving treatment, TTR mutation analysis should be considered in cases of HCM not explained by mutations in sarcomeric protein genes.     

Acute myocardial infarction with diminutive right coronary artery and obstructive hypertrophic cardiomyopathy without significant coronary stenoses

Focal tissue abnormalities consistent with regional ischemia have been reported in patients with hypertrophic cardiomyopathy (HCM). Coronary microvascular dysfunction has been also reported to be present in patients with HCM despite normal epicardial coronary arteries. Moreover, it has been demonstrated that in the case of HCM and idiopathic left ventricular hypertrophy, hypoplastic coronary arteries as diminutive vessels are present and that obstructive hypertrophic cardiomyopathy is associated with enhanced thrombin generation and platelet activation. Previously, it has been described an acute myocardial infarction in a young athlete with non-obstructive hypertrophic cardiomyopathy and normal coronary arteries. We present a case of an acute myocardial infarction with diminutive right coronary artery and obstructive hypertrophic cardiomyopathy without significant coronary stenoses. To our knowledge, this is the first report of an acute myocardial infarction with diminutive right coronary artery and obstructive hypertrophic cardiomyopathy without significant coronary stenoses.     

家族性肥厚型心肌病致病基因的筛查分析

目的鉴定一个肥厚型心肌病家系的致病基因。方法根据肥厚型心肌病（HCM）已知的13个致病基因，每个基因选取3个微卫星（Marker）标记对该家系进行筛查分析，对不能排除的基因采取PCR一直接测序技术进行鉴定。结果13个候选基因中仅CRP3不能被排除，测序未发现该基因外显子有任何突变。结论已知的13个肥厚型心肌病致病基因不是该汉族家系的致病基因，该HCM家系很可能由一新的致病基因突变所致。     

Expression profiling of cardiac genes in human hypertrophic cardiomyopathy: insight into the pathogenesis of phenotypes

OBJECTIVES: The goal of this study was to identify genes upregulated in the heart in human patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Hypertrophic cardiomyopathy is a genetic disease caused by mutations in contractile sarcomeric proteins. The molecular basis of diverse clinical and pathologic phenotypes in HCM remains unknown. METHODS: We performed polymerase chain reaction-select complementary DNA subtraction between normal hearts and hearts with HCM and screened subtracted libraries by Southern blotting. We sequenced the differentially expressed clones and performed Northern blotting to detect increased expression levels. RESULTS: We screened 288 independent clones, and 76 clones had less than twofold increase in the signal intensity and were considered upregulated. Sequence analysis identified 36 genes including those encoding the markers of pressure overload-induced ("secondary") cardiac hypertrophy, cytoskeletal proteins, protein synthesis, redox system, ion channels and those with unknown function. Northern blotting confirmed increased expression of skeletal muscle alpha-actin (ACTA1), myosin light chain 2a (MLC2a), GTP-binding protein Gs-alpha subunit (GNAS1), NADH ubiquinone oxidoreductase (NDUFB10), voltage-dependent anion channel 1 (VDAC1), four-and-a-half LIM domain protein 1 (FHL1) (also known as SLIM1), sarcosin (SARCOSIN) and heat shock 70kD protein 8 (HSPA8) by less than twofold. Expression levels of ACTA1, MLC2a and GNAS1 were increased in six additional and FHL1 in four additional hearts with HCM. CONCLUSIONS: A diverse array of genes is upregulated in the heart in human patients with HCM, which could account for the diversity of clinical and pathologic phenotypes. Markers of secondary hypertrophy are also upregulated, suggesting commonality of pathways involved in HCM and the acquired forms of cardiac hypertrophy. Elucidation of the role of differentially expressed genes in HCM could provide for new therapeutic targets.     

目标基因捕获测序技术鉴定肥厚型心肌病致病突变的研究

目的:利用目标基因靶向捕获高通量测序方法鉴定肥厚型心肌病(hypertrophic cardiomyopathy,HCM)致病突变,并进行基因型-临床表型的分析,以期对临床诊治提供参考依据。方法:连续收集10例HCM患者血液与临床资料。提取全血基因组DNA、文库制备,靶向富集8个编码肌小节蛋白的HCM的致病基因,并行高通量测序。结果:10例患者[平均年龄为(46±7.9)岁,女性占50%]中,4例患者发现5个基因突变位点。双突变(TNNT2 R286H和MYH7 R663H)携带者具有HCM家族史,发病早,左心室重度肥厚,心电图呈现传导阻滞。MYBPC3 D770N和MYBPC3 S236G突变携带者发病年龄晚,左心室肥厚程度较轻。MYH7 R869C突变携带者年龄大,左心室肥厚程度较重,心电图呈现明显左心室肥大证据。结论:对10例HCM患者利用目标基因捕获测序技术筛选出5个致病突变。携带不同突变的患者其临床表型不一致,这对患者的预后和治疗提供了有利的依据。