S-Nitrosylation of Muscle LIM Protein Facilitates Myocardial Hypertrophy Through Toll-Like Receptor 3-Mediated Receptor-Interacting Protein Kinase 3 and NLRP3 Inflammasome Activation.
肌肉 LIM 蛋白的 S-亚硝基化通过 Toll 样受体 3 介导的受体相互作用蛋白激酶 3 和 NLRP3 炎性体激活促进心肌肥厚。
- 作者列表："Tang X","Pan L","Zhao S","Dai F","Chao M","Jiang H","Li X","Lin Z","Huang Z","Meng G","Wang C","Chen C","Liu J","Wang X","Ferro A","Wang H","Chen H","Gao Y","Lu Q","Xie L","Han Y","Ji Y
:Background: S-nitrosylation (SNO), a prototypic redox-based posttranslational modification, is involved in the pathogenesis of cardiovascular disease. The aim of this study was to determine the role of S-nitrosylation of muscle LIM protein (MLP) in myocardial hypertrophy, as well as the mechanism by which SNO-MLP modulates hypertrophic growth in response to pressure overload. Methods: Myocardial samples from patients and animal models exhibiting myocardial hypertrophy were examined for SNO-MLP level using biotin-switch methods. S-nitrosylation sites were further identified through liquid chromatography-tandem mass spectrometry (LCMS/MS). Denitrosylation of MLP by the mutation of nitrosylation sites or overexpression of S-nitrosoglutathione reductase (GSNOR) was used to analyze the contribution of SNO-MLP in myocardial hypertrophy. Downstream effectors of SNO-MLP were screened through mass spectrometry (MS) and confirmed by co-immunoprecipitation. Recruitment of toll-like receptor 3 (TLR3) by SNO-MLP in myocardial hypertrophy was examined in TLR3 small interfering RNA (siRNA)-transfected neonatal rat cardiomyocytes (NRCMs) and in TLR3 knockout mouse model. Results: SNO-MLP level was significantly higher in hypertrophic myocardium from patients and in spontaneously hypertensive rats and mice subjected to transverse aortic constriction (TAC). The level of SNO-MLP also increased in angiotensin II (Ang II) or phenylephrine (PE)-treated NRCMs. S-nitrosylated site of MLP at cysteine (Cys) 79 was identified by LCMS/MS and further confirmed in NRCMs. Mutation of Cys79 significantly reduced hypertrophic growth in Ang II or PE-treated NRCMs and TAC mice. Reducing MLP Snitrosylation level by overexpression of S-nitrosoglutathione reductase greatly attenuated myocardial hypertrophy. Mechanistically, MLP S-nitrosylation stimulated TLR3 binding to MLP in response to hypertrophic stimuli, and disrupting this interaction by downregulating TLR3 attenuated myocardial hypertrophy. SNO-MLP also increased the complex formation between TLR3 and receptor-interacting protein kinase 3 (RIP3). This interaction in turn induced NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome activation, thereby promoting the development of myocardial hypertrophy. Conclusions: Our findings revealed a key role of SNO-MLP in myocardial hypertrophy and demonstrated TLR3-mediated RIP3 and NLRP3 inflammasome activation as the downstream signaling pathway, which may represent a novel therapeutic target for myocardial hypertrophy and heart failure.
背景: S-亚硝基化 (SNO) 是一种基于原型氧化还原的翻译后修饰，参与心血管疾病的发病机制。本研究的目的是确定 S-亚硝基化肌肉 LIM 蛋白 (MLP) 在心肌肥厚中的作用, 以及 SNO-MLP 调节压力过载后肥大生长的机制。方法: 采用生物素-开关法检测心肌肥厚病人和动物模型的心肌标本中 SNO-MLP 水平。通过液相色谱-串联质谱 (LCMS/MS) 进一步鉴定 S-亚硝基化位点。通过亚硝基化位点突变或过表达 S-亚硝基谷胱甘肽还原酶 (GSNOR) 对 MLP 进行反硝化，分析 SNO-MLP 在心肌肥厚中的贡献。通过质谱 (MS) 筛选 SNO-MLP 的下游效应器，并通过免疫共沉淀确认。在 TLR3 小干扰 RNA (siRNA) 转染的乳鼠心肌细胞 (ncms) 中检测了 SNO-MLP 对心肌肥厚中 toll 样受体 3 (TLR3) 的募集并在 TLR3 基因敲除小鼠模型中。结果: SNO-MLP 水平在来自患者的肥厚心肌以及自发性高血压大鼠和接受横主动脉缩窄术 (TAC) 的小鼠中显著升高。在血管紧张素 II (Ang II) 或去氧肾上腺素 (PE) 治疗的 ncms 中，SNO-MLP 水平也增加。MLP 在半胱氨酸 (Cys) 79 处的 S-亚硝基化位点经 LCMS/MS 鉴定，并在 NRCMs 中进一步证实。Cys79 突变显著降低 Ang II 或 PE 处理的 ncms 和 TAC 小鼠的肥大生长。通过过表达 S-亚硝基谷胱甘肽还原酶降低 MLP 亚硝基化水平大大减弱心肌肥厚。机械上，MLP S-亚硝基化刺激 TLR3 与 MLP 结合，以响应肥大刺激，并通过下调 TLR3 破坏这种相互作用，减弱心肌肥厚。SNO-MLP 还增加了 TLR3 和受体相互作用蛋白激酶 3 (RIP3) 之间的复合物形成。这种相互作用反过来诱导 NOD 样受体 pyrin 结构域包含 3 (NLRP3) 炎症小体的激活，从而促进心肌肥厚的发展。结论: 我们的研究结果揭示了 SNO-MLP 在心肌肥厚中的关键作用，并证明 RIP3 和 NLRP3 炎症小体激活作为下游信号通路 TLR3-mediated, 这可能是心肌肥厚和心力衰竭的一个新的治疗靶点。
METHODS:Abstract Background Ischemic cardiomyopathy is a high-cost, resource-intensive public health burden that is associated with a 1-year mortality rate of about 16% in western population. Different in patient ethnicity and pattern of practice may impact the clinical outcome. We aim to determine 1-year mortality and to identify factors that significantly predicts 1-year mortality of Thai patients with ischemic cardiomyopathy. Methods This prospective multicenter registry enrolled consecutive Thai patients that were diagnosed with ischemic cardiomyopathy at 9 institutions located across Thailand. Patients with left ventricular function 75% in the left main or proximal left anterior descending artery or coronary angiography, and/or two major epicardial coronary stenoses; 2) prior myocardial infarction; 3) prior revascularization by coronary artery bypass graft or percutaneous coronary intervention; or, 4) magnetic resonance imaging pattern compatible with ischemic cardiomyopathy. Baseline clinical characteristics, coronary and echocardiographic data were recorded. The 1-year clinical outcome was pre-specified. Results Four hundred and nineteen patients were enrolled. Thirty-nine patients (9.9%) had died at 1 year, with 27 experiencing cardiovascular death, and 12 experiencing non-cardiovascular death. A comparison between patients who were alive and patients who were dead at 1 year revealed lower baseline left ventricular ejection fraction (LVEF) (26.7 ± 7.6% vs 30.2 ± 7.8%; p = 0.021), higher left ventricular end-diastolic volume (LVEDV) (185.8 ± 73.2 ml vs 155.6 ± 64.2 ml; p = 0.014), shorter mitral valve deceleration time (142.9 ± 57.5 ml vs 182.4 ± 85.7 ml; p = 0.041), and lower use of statins (94.7% vs 99.7%; p = 0.029) among deceased patients. Patients receiving guideline-recommended β-blockers had lower mortality than patients receiving non-guideline-recommended β-blockers (8.1% vs 18.2%; p = 0.05). Conclusions The results of this study revealed a 9.9% 1-year mortality rate among Thai ischemic cardiomyopathy patients. Doppler echocardiographic parameters significantly associated with 1-year mortality were LVEF, LVEDV, mitral E velocity, and mitral valve deceleration time. The use of non-guideline-recommended β-blockers rather than guideline recommended β-blockers were associated with increased with 1-year mortality. Guidelines recommended β-blockers should be preferred. Trial registration Thai Clinical Trials Registry TCTR20190722002. Registered 22 July 2019. “Retrospectively registered”.
METHODS:Abstract Background Peripartum cardiomyopathy (PPCM) is rare and potentially life-threatening; its etiology remains unclear. Imaging characteristics on cardiovascular magnetic resonance (CMR) and their prognostic significance have rarely been studied. We sought to determine CMR’s prognostic value in PPCM by using T1 and T2 mapping techniques. Methods Data from 21 PPCM patients from our CMR registry database were analyzed. The control group comprised 20 healthy age-matched females. All subjects underwent comprehensive contrast-enhanced CMR. T1 and T2 mapping using modified Look-Locker inversion recovery and T2 prep balanced steady-state free precession sequences, respectively. Ventricular size and function, late gadolinium enhancement (LGE), myocardial T1 value, extracellular volume (ECV), and T2 value were analyzed. Transthoracic echocardiography was performed at baseline and during follow-up. The recovered left ventricular ejection fraction (LVEF) was defined as LVEF ≥50% on echocardiography follow-up after at least 6 months of the diagnosis. Results CMR imaging showed that the PPCM patients had severely impaired LVEF and right ventricular ejection fraction (LVEF: 26.8 ± 10.6%; RVEF: 33.9 ± 14.6%). LGE was seen in eight (38.1%) cases. PPCM patients had significantly higher native T1 and ECV (1345 ± 79 vs. 1212 ± 32 ms, P < 0.001; 33.9 ± 5.2% vs. 27.1 ± 3.1%, P < 0.001; respectively) and higher myocardial T2 value (42.3 ± 3.7 vs. 36.8 ± 2.3 ms, P < 0.001) than did the normal controls. After a median 2.5-year follow-up (range: 8 months-5 years), six patients required readmission for heart failure, two died, and 10 showed left ventricular function recovery. The LVEF-recovered group showed significantly lower ECV (30.7 ± 2.1% vs. 36.8 ± 5.6%, P = 0.005) and T2 (40.6 ± 3.0 vs. 43.9 ± 3.7 ms, P = 0.040) than the unrecovered group. Multivariable logistic regression analysis showed ECV (OR = 0.58 for per 1% increase, P = 0.032) was independently associated with left ventricular recovery in PPCM. Conclusions Compared to normal controls, PPCM patients showed significantly higher native T1, ECV, and T2. Native T1, ECV, and T2 were associated with LVEF recovery in PPCM. Furthermore, ECV could independently predict left ventricular function recovery in PPCM.
METHODS:BACKGROUND:Atrial fibrillation (AF) is the most common arrhythmia in hypertrophic cardiomyopathy (HCM) and is associated with adverse outcomes in HCM patients. Although the left atrial (LA) diameter has consistently been identified as a strong predictor of AF in HCM patients, the relationship between LA dysfunction and AF still remains unclear. The aim of this study is to evaluate the LA function in patients with non-obstructive HCM (NOHCM) utilizing cardiovascular magnetic resonance feature tracking (CMR-FT).,METHODS:Thirty-three patients with NOHCM and 28 healthy controls were studied. The global and regional LA function and left ventricular (LV) function were compared between the two groups. The following LA global functional parameters were quantitively analyzed: reservoir function (total ejection fraction [LA total EF], total strain [ε], peak positive strain rate [SRs]), conduit function (passive ejection fraction [LA passive EF], passive strain [ε], peak early-negative SR [SRe]), and booster pump function (active ejection fraction [LA active EF], active strain [ε], peak late-negative SR [SRa]). The LA wall was automatically divided into 6 segments: anterior, antero-roof, inferior, septal, septal-roof and lateral. Three LA strain parameters (ε, ε, ε) and their corresponding strain rate parameters (SRs, SRe, SRa) during the reservoir, conduit and booster pump LA phases were segmentally measured and analyzed.,RESULTS:The LA reservoir (LA total EF: 57.6 ± 8.2% vs. 63.9 ± 6.4%, p < 0.01; ε: 35.0 ± 12.0% vs. 41.5 ± 11.2%, p = 0.03; SRs: 1.3 ± 0.4 s vs. 1.5 ± 0.4 s, p = 0.02) and conduit function (LA passive EF: 28.7 ± 9.1% vs. 37.1 ± 10.0%, p < 0.01; ε: 18.7 ± 7.9% vs. 25.9 ± 10.0%, p < 0.01; SRe: - 0.8 ± 0.3 s vs. -1.1 ± 0.4 s, p < 0.01) were all impaired in patients with NOHCM when compared with healthy controls, while LA booster pump function was preserved. The LA segmental strain and strain rate analysis demonstrated that the ε, ε, SRe of inferior, SRs, SRe of septal-roof, and SRa of antero-roof walls (all p < 0.05) were all decreased in the NOHCM cohort. Correlations between LA functional parameters and LV conventional function and LA functional parameters and baseline parameters (age, body surface area and NYHA classification) were weak. The two strongest relations were between ε and LA total EF(r = 0.84, p < 0.01), ε and LA active EF (r = 0.83, p < 0.01).,CONCLUSIONS:Compared with healthy controls, patients with NOHCM have LA reservoir and conduit dysfunction, and regional LA deformation before LA enlargement. CMR-FT identifies LA dysfunction and deformation at an early stage.