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3.
J Biol Chem ; 300(5): 107255, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38579991

RESUMO

Myocardial failure is associated with adverse remodeling, including loss of cardiomyocytes, hypertrophy, and alterations in cell-cell contacts. Striatin-interacting phosphatase and kinase (STRIPAK) complexes and their mammalian STE20-like kinase 4 (Mst4) have been linked to development of different diseases. The role and targets of Mst4 in cardiomyocytes have not been investigated yet. Multitissue immunoblot experiments show highly enriched Mst4 expression in rodent hearts. Analyses of human biopsy samples from patients suffering from dilated cardiomyopathy revealed that Mst4 is upregulated (5- to 8-fold p < 0.001) compared with nonfailing controls. Increased abundance of Mst4 could also be detected in mouse models of cardiomyopathy. We confirmed that Mst4 interacts with STRIPAK components in neonatal rat ventricular cardiomyocytes, indicating that STRIPAK is present in the heart. Immunofluorescence stainings and molecular interaction studies revealed that Mst4 is localized to the intercalated disc and interacts with several intercalated disc proteins. Overexpression of Mst4 in cardiomyocytes results in hypertrophy compared with controls. In adult rat cardiomyocytes, Mst4 overexpression increases cellular and sarcomeric fractional shortening (p < 0.05), indicating enhanced contractility. Overexpression of Mst4 also inhibits apoptosis shown by reduction of cleaved caspase3 (-69%, p < 0.0001), caspase7 (-80%, p < 0.0001), and cleaved Parp1 (-27%, p < 0.001). To elucidate potential Mst4 targets, we performed phosphoproteomics analyses in neonatal rat cardiomyocytes after Mst4 overexpression and inhibition. The results revealed target candidates of Mst4 at the intercalated disc. We identified Mst4 as a novel cardiac kinase that is upregulated in cardiomyopathy-regulating cardiomyocyte growth and survival.

4.
Biomarkers ; 29(4): 205-210, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38588595

RESUMO

BACKGROUND: Currently available risk scores fail to accurately predict morbidity and mortality in patients with severe symptomatic aortic stenosis who undergo transcatheter aortic valve implantation (TAVI). In this context, biomarkers like matrix metalloproteinase-2 (MMP-2) and Galectin-3 (Gal-3) may provide additional prognostic information. METHODS: Patients with severe aortic stenosis undergoing consecutive, elective, transfemoral TAVI were included. Baseline demographic data, functional status, echocardiographic findings, clinical outcomes and biomarker levels were collected and analysed. RESULTS: The study cohort consisted of 89 patients (age 80.4 ± 5.1 years, EuroScore II 7.1 ± 5.8%). During a median follow-up period of 526 d, 28 patients (31.4%) died. Among those who died, median baseline MMP-2 (alive: 221.6 [170.4; 263] pg/mL vs. deceased: 272.1 [225; 308.8] pg/mL, p < 0.001) and Gal-3 levels (alive: 19.1 [13.5; 24.6] pg/mL vs. deceased: 25 [17.6; 29.5] pg/mL, p = 0.006) were higher than in survivors. In ROC analysis, MMP-2 reached an acceptable level of discrimination to predict mortality (AUC 0.733, 95% CI [0.62; 0.83], p < 0.001), but the predictive value of Gal-3 was poor (AUC 0.677, 95% CI [0.56; 0.79], p = 0.002). Kaplan-Meier and Cox regression analyses showed that patients with MMP-2 and Gal-3 concentrations above the median at baseline had significantly impaired long-term survival (p = 0.004 and p = 0.02, respectively). CONCLUSIONS: In patients with severe aortic stenosis undergoing transfemoral TAVI, MMP-2 and to a lesser extent Gal-3, seem to have additive value in optimizing risk prediction and streamlining decision-making.


Assuntos
Estenose da Valva Aórtica , Biomarcadores , Galectina 3 , Metaloproteinase 2 da Matriz , Substituição da Valva Aórtica Transcateter , Humanos , Metaloproteinase 2 da Matriz/sangue , Substituição da Valva Aórtica Transcateter/mortalidade , Biomarcadores/sangue , Masculino , Feminino , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/sangue , Galectina 3/sangue , Idoso de 80 Anos ou mais , Idoso , Prognóstico , Galectinas , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo
5.
Inn Med (Heidelb) ; 65(5): 431-438, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38635087

RESUMO

The pathophysiology of aortic valve diseases is of predominantly degenerative nature, characterized by calcific aortic valve stenosis, which is associated with a reduction in prognosis. The prevalence of aortic valve insufficiency also increases with advancing age. Timely causal treatment is crucial in the management of aortic valve diseases. Following the indication for intervention, the heart team plays a central role in evaluating the results and making therapeutic decisions that consider the patient's preferences. In the assessment of treatment options, considerations regarding the long-term perspective are particularly crucial, especially in younger patients. The most common therapeutic approach for aortic valve diseases is the introduction of a new valve prosthesis. In the majority of cases, this is now achieved through catheter-based implantation of a bioprosthetic heart valve, known as transcatheter aortic valve implantation (TAVI). Open surgical aortic valve replacement (AVR) is favored in younger patients with low surgical risk or in the case that TAVI is not feasible. In AVR, both biological and the longest-lasting mechanical prosthesis types are used. Surgical repair techniques are primarily applied in cases of aortic valve regurgitation. Notably, TAVI, as well as surgical procedures for the treatment of aortic valve diseases, have undergone significant advancements in recent years, including expanded indications for TAVI and, on the surgical side, in particular the development of minimally invasive surgical techniques.


Assuntos
Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Valva Aórtica/cirurgia , Valva Aórtica/patologia , Próteses Valvulares Cardíacas , Valvopatia Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/instrumentação , Estenose da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/fisiopatologia , Bioprótese
6.
Heart Rhythm ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604590

RESUMO

BACKGROUND: The CASTLE-HTx trial demonstrated the benefit of atrial fibrillation (AF) ablation compared with medical therapy in decreasing mortality, need for left ventricular assist device implantation, or heart transplantation (HTx) in patients with end-stage heart failure (HF). OBJECTIVE: This analysis aimed to identify risk factors related to adverse outcomes in patients with end-stage HF and to assess the impact of ablation. METHODS: The CASTLE-HTx protocol randomized 194 patients with end-stage HF and AF to ablation vs medical therapy. We identified left ventricular ejection fraction <30%, New York Heart Association class ≥III, and AF burden >50% as predictors for the primary end point. The CASTLE-HTx risk score assigned weights to these risk factors. Patients with a risk score ≥3 were identified as high risk. RESULTS: The patients were assigned to low-risk (89 [45.9%]) and high-risk (105 [54.1%]) groups. After a median follow-up of 18 months, a primary end point event occurred in 6 and 31 patients of the low- and high-risk groups (hazard ratio, 4.98; 95% confidence interval, 2.08-11.9). The incidence rate (IR) difference between ablation and medical therapy was much larger in high-risk patients (8/49 [IR, 11.4] vs 23/56 [IR, 36.1]) compared with low-risk patients (2/48 [IR, 2.6] vs 4/41 [IR, 6.3]). The IR difference for ablation was significantly higher in high-risk patients (24.69) compared with low-risk patients (3.70). CONCLUSION: The absolute benefit of ablation is more pronounced in high-risk patients, but low-risk patients may also benefit. The CASTLE-HTx risk score identifies patients with end-stage HF who will particularly benefit from ablation.

7.
Life (Basel) ; 14(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38541655

RESUMO

BACKGROUND: Arrhythmia-induced cardiomyopathy (AIC) is characterized by the reversibility of left ventricular (LV) systolic dysfunction (LVSD) after rhythm restoration. This study is a cardiac magnetic resonance tomography substudy of our AIC trial with the purpose to investigate whether left ventricular fibrosis affects the time to recovery (TTR) in patients with AIC. METHOD: Patients with newly diagnosed and otherwise unexplainable LVSD and tachyarrhythmia were prospectively recruited. LV ejection fraction (LVEF) was measured by echocardiography at baseline and 2, 4, and 6 months after rhythm control, and stress markers were assessed. After initial rhythm control, LV fibrosis was assessed through late gadolinium enhancement (LGE). Patients were diagnosed with AIC if their LVEF improved by ≥15% (or ≥10% when LVEF reached ≥50%). Non-responders served as controls (non-AIC). RESULTS: The LGE analysis included 39 patients, 31 of whom recovered (AIC). LV end-systolic diameters decreased and LVEF increased during follow-up. LV LGE content correlated positively with TTR (r = 0.63, p = 0.003), with less LGE favoring faster recovery, and negatively with ΔLVEF (i.e., LVEF at month 2 compared to baseline) as a marker of fast recovery (r = -0.55, p = 0.012), suggesting that LV fibrosis affects the speed of recovery. CONCLUSION: LV fibrosis correlated positively with the time to recovery in patients with AIC. This correlation may help in the estimation of the recovery period and in the optimization of diagnostic and therapeutic strategies for patients with AIC.

8.
EuroIntervention ; 20(6): e363-e375, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38506737

RESUMO

BACKGROUND: There is a lack of comparative data on transcatheter aortic valve implantation (TAVI) in degenerated surgical prostheses (valve-in-valve [ViV]). AIMS: We sought to compare outcomes of using two self-expanding transcatheter heart valve (THV) systems for ViV. METHODS: In this retrospective multicentre registry, we included consecutive patients undergoing transfemoral ViV using either the ACURATE neo/neo2 (ACURATE group) or the Evolut R/PRO/PRO+ (EVOLUT group). The primary outcome measure was technical success according to Valve Academic Research Consortium (VARC)-3. Secondary outcomes were 30-day all-cause mortality, device success (VARC-3), coronary obstruction (CO) requiring intervention, rates of severe prosthesis-patient mismatch (PPM), and aortic regurgitation (AR) ≥moderate. Comparisons were made after 1:1 propensity score matching. RESULTS: The study cohort comprised 835 patients from 20 centres (ACURATE n=251; EVOLUT n=584). In the matched cohort (n=468), technical success (ACURATE 92.7% vs EVOLUT 88.9%; p=0.20) and device success (69.7% vs 73.9%; p=0.36) as well as 30-day mortality (2.8% vs 1.6%; p=0.392) were similar between the two groups. The mean gradients and rates of severe PPM, AR ≥moderate, or CO did not differ between the groups. Technical and device success were higher for the ACURATE platform among patients with a true inner diameter (ID) >19 mm, whereas a true ID ≤19 mm was associated with higher device success - but not technical success - among Evolut recipients. CONCLUSIONS: ViV TAVI using either ACURATE or Evolut THVs showed similar procedural outcomes. However, a true ID >19 mm was associated with higher device success among ACURATE recipients, whereas in patients with a true ID ≤19 mm, device success was higher when using Evolut.


Assuntos
Insuficiência da Valva Aórtica , Bioprótese , Oclusão Coronária , Substituição da Valva Aórtica Transcateter , Humanos , Catéteres , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Valvas Cardíacas , Sistema de Registros , Substituição da Valva Aórtica Transcateter/efeitos adversos
9.
Artigo em Inglês | MEDLINE | ID: mdl-38483417

RESUMO

BACKGROUND: Arrhythmia-induced cardiomyopathy (AIC) is a known entity, but prospective evidence for its characterization is limited. OBJECTIVES: This study aimed to: 1) determine the relative frequency of the pure form of AIC in the clinically relevant cohort of patients with newly diagnosed, otherwise unexplained left ventricular systolic dysfunction (LVSD) and tachyarrhythmia; 2) assess the time to recovery from LVSD; and 3) identify parameters for an early diagnosis of AIC. METHODS: Patients were prospectively included, underwent effective rhythm restoration, and were followed-up at 2, 4, and 6 months to evaluate clinical characteristics, biomarkers, and cardiac imaging including cardiac magnetic resonance imaging. Patients with recurred arrhythmia were excluded from analysis. RESULTS: 41 of 50 patients were diagnosed with AIC 6 months after rhythm restoration. Left ventricular (LV) ejection fraction increased 2 months after rhythm restoration from 35.4% ± 8.2% to 52.7% ± 8.0% in AIC patients vs 37.0% ± 9.5% to 43.3% ± 7.0% in non-AIC patients. From month 2 to 6, LV ejection fraction continued to increase in AIC patients (57.2% ± 6.1%; P < 0.001) but remained stable in non-AIC patients (44.0% ± 7.8%; P = 0.628). Multivariable logistic regression analysis revealed that lower LV end-diastolic diameter at baseline could be used for early diagnosis of AIC, whereas biomarkers and other morphological or functional parameters, including late LV gadolinium enhancement, did not show suitability for early diagnosis. CONCLUSIONS: We observed a high prevalence of AIC in patients with otherwise unexplained LVSD and concomitant tachyarrhythmia, suggesting that this condition may be underdiagnosed in clinical practice. Most patients recovered fast, within months, from LVSD. A low initial LV end-diastolic diameter may constitute an early marker for diagnosis of AIC.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38379024

RESUMO

Although cardiovascular diseases are the leading cause of death worldwide, their pharmacotherapy remains suboptimal. Thus, there is a clear unmet need to develop more effective and safer pharmacological strategies. In this review, we summarize the most relevant advances in cardiovascular pharmacology in 2023, including the approval of first-in-class drugs that open new avenues for the treatment of atherosclerotic cardiovascular disease and heart failure. The new indications of drugs already marketed (repurposing) for the treatment of obstructive hypertrophic cardiomyopathy, hypercholesterolemia, type 2 diabetes, obesity and heart failure, the impact of polypharmacy on guideline-directed drug use is highlighted as well as results from negative clinical trials. Finally, we end with a summary of the most important phase 2 and 3 clinical trials assessing the efficacy and safety of cardiovascular drugs under development for the prevention and treatment of cardiovascular diseases.

13.
Catheter Cardiovasc Interv ; 102(7): 1376-1385, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37727885

RESUMO

OBJECTIVES: The aim of the current study was to analyze the clinical and procedural predictors of thrombocytopenia and the relationship between the decrease in platelet count (DPC) and change in vWF function (ΔvWF) after transcatheter aortic valve replacement (TAVR). BACKGROUND: TAVR often causes temporary thrombocytopenia. At the same time, TAVR leads to a restoration of von Willebrand factor (vWF) function. METHODS: One hundred and forty-one patients with severe aortic stenosis undergoing TAVR were included in the study. Platelet count and vWF function (vWF:Ac/Ag ratio) were assessed at baseline and 6 h after TAVR. Thrombocytopenia was defined as platelet count <150/nL. RESULTS: Median platelet count at baseline was 214/nL (interquartile range [IQR]: 176-261) and decreased significantly to 184/nL (IQR: 145-222) 6 h after TAVR. The number of patients with thrombocytopenia increased from 12.8% at baseline to 29.1% after 6 h. DPC 6 h after TAVR showed a significant correlation with ΔvWF (r = - 0.254, p = 0.002). Patients with DPC > 20% had significantly higher ΔvWF (10.9% vs. 6.5%, p = 0.021). Obese patients showed a significantly lower DPC (11.8% vs. 19.9%, p = 0.001). In multivariate analysis, ΔvWF 6 h after TAVR was the only significant predictor for DPC > 20% (p = 0.017). CONCLUSIONS: The restoration of vWF after TAVR is a significant predictor for DPC after TAVR. An increased platelet consumption due to vWF restoration could play a key role in the development of thrombocytopenia after TAVR.


Assuntos
Estenose da Valva Aórtica , Trombocitopenia , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Fator de von Willebrand , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Resultado do Tratamento , Fatores de Risco , Trombocitopenia/diagnóstico , Trombocitopenia/etiologia
14.
N Engl J Med ; 389(15): 1380-1389, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37634135

RESUMO

BACKGROUND: The role of catheter ablation in patients with symptomatic atrial fibrillation and end-stage heart failure is unknown. METHODS: We conducted a single-center, open-label trial in Germany that involved patients with symptomatic atrial fibrillation and end-stage heart failure who were referred for heart transplantation evaluation. Patients were assigned to receive catheter ablation and guideline-directed medical therapy or medical therapy alone. The primary end point was a composite of death from any cause, implantation of a left ventricular assist device, or urgent heart transplantation. RESULTS: A total of 97 patients were assigned to the ablation group and 97 to the medical-therapy group. The trial was stopped for efficacy by the data and safety monitoring board 1 year after randomization was completed. Catheter ablation was performed in 81 of 97 patients (84%) in the ablation group and in 16 of 97 patients (16%) in the medical-therapy group. After a median follow-up of 18.0 months (interquartile range, 14.6 to 22.6), a primary end-point event had occurred in 8 patients (8%) in the ablation group and in 29 patients (30%) in the medical-therapy group (hazard ratio, 0.24; 95% confidence interval [CI], 0.11 to 0.52; P<0.001). Death from any cause occurred in 6 patients (6%) in the ablation group and in 19 patients (20%) in the medical-therapy group (hazard ratio, 0.29; 95% CI, 0.12 to 0.72). Procedure-related complications occurred in 3 patients in the ablation group and in 1 patient in the medical-therapy group. CONCLUSIONS: Among patients with atrial fibrillation and end-stage heart failure, the combination of catheter ablation and guideline-directed medical therapy was associated with a lower likelihood of a composite of death from any cause, implantation of a left ventricular assist device, or urgent heart transplantation than medical therapy alone. (Funded by Else Kröner-Fresenius-Stiftung; CASTLE-HTx ClinicalTrials.gov number, NCT04649801.).


Assuntos
Fibrilação Atrial , Ablação por Cateter , Insuficiência Cardíaca , Humanos , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Alemanha , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Coração Auxiliar , Encaminhamento e Consulta , Resultado do Tratamento
15.
Science ; 381(6654): 231-239, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37440641

RESUMO

Atrial fibrillation disrupts contraction of the atria, leading to stroke and heart failure. We deciphered how immune and stromal cells contribute to atrial fibrillation. Single-cell transcriptomes from human atria documented inflammatory monocyte and SPP1+ macrophage expansion in atrial fibrillation. Combining hypertension, obesity, and mitral valve regurgitation (HOMER) in mice elicited enlarged, fibrosed, and fibrillation-prone atria. Single-cell transcriptomes from HOMER mouse atria recapitulated cell composition and transcriptome changes observed in patients. Inhibiting monocyte migration reduced arrhythmia in Ccr2-∕- HOMER mice. Cell-cell interaction analysis identified SPP1 as a pleiotropic signal that promotes atrial fibrillation through cross-talk with local immune and stromal cells. Deleting Spp1 reduced atrial fibrillation in HOMER mice. These results identify SPP1+ macrophages as targets for immunotherapy in atrial fibrillation.


Assuntos
Fibrilação Atrial , Macrófagos , Osteopontina , Animais , Humanos , Camundongos , Fibrilação Atrial/genética , Fibrilação Atrial/imunologia , Átrios do Coração , Macrófagos/imunologia , Insuficiência da Valva Mitral/genética , Osteopontina/genética , Deleção de Genes , Movimento Celular , Análise da Expressão Gênica de Célula Única
16.
Eur Heart J Digit Health ; 4(3): 265-274, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37265858

RESUMO

Aims: One of the most important complications of heart transplantation is organ rejection, which is diagnosed on endomyocardial biopsies by pathologists. Computer-based systems could assist in the diagnostic process and potentially improve reproducibility. Here, we evaluated the feasibility of using deep learning in predicting the degree of cellular rejection from pathology slides as defined by the International Society for Heart and Lung Transplantation (ISHLT) grading system. Methods and results: We collected 1079 histopathology slides from 325 patients from three transplant centres in Germany. We trained an attention-based deep neural network to predict rejection in the primary cohort and evaluated its performance using cross-validation and by deploying it to three cohorts. For binary prediction (rejection yes/no), the mean area under the receiver operating curve (AUROC) was 0.849 in the cross-validated experiment and 0.734, 0.729, and 0.716 in external validation cohorts. For a prediction of the ISHLT grade (0R, 1R, 2/3R), AUROCs were 0.835, 0.633, and 0.905 in the cross-validated experiment and 0.764, 0.597, and 0.913; 0.631, 0.633, and 0.682; and 0.722, 0.601, and 0.805 in the validation cohorts, respectively. The predictions of the artificial intelligence model were interpretable by human experts and highlighted plausible morphological patterns. Conclusion: We conclude that artificial intelligence can detect patterns of cellular transplant rejection in routine pathology, even when trained on small cohorts.

17.
Circ Res ; 133(2): e19-e46, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37313752

RESUMO

BACKGROUND: Systemic defects in intestinal iron absorption, circulation, and retention cause iron deficiency in 50% of patients with heart failure. Defective subcellular iron uptake mechanisms that are independent of systemic absorption are incompletely understood. The main intracellular route for iron uptake in cardiomyocytes is clathrin-mediated endocytosis. METHODS: We investigated subcellular iron uptake mechanisms in patient-derived and CRISPR/Cas-edited induced pluripotent stem cell-derived cardiomyocytes as well as patient-derived heart tissue. We used an integrated platform of DIA-MA (mass spectrometry data-independent acquisition)-based proteomics and signaling pathway interrogation. We employed a genetic induced pluripotent stem cell model of 2 inherited mutations (TnT [troponin T]-R141W and TPM1 [tropomyosin 1]-L185F) that lead to dilated cardiomyopathy (DCM), a frequent cause of heart failure, to study the underlying molecular dysfunctions of DCM mutations. RESULTS: We identified a druggable molecular pathomechanism of impaired subcellular iron deficiency that is independent of systemic iron metabolism. Clathrin-mediated endocytosis defects as well as impaired endosome distribution and cargo transfer were identified as a basis for subcellular iron deficiency in DCM-induced pluripotent stem cell-derived cardiomyocytes. The clathrin-mediated endocytosis defects were also confirmed in the hearts of patients with DCM with end-stage heart failure. Correction of the TPM1-L185F mutation in DCM patient-derived induced pluripotent stem cells, treatment with a peptide, Rho activator II, or iron supplementation rescued the molecular disease pathway and recovered contractility. Phenocopying the effects of the TPM1-L185F mutation into WT induced pluripotent stem cell-derived cardiomyocytes could be ameliorated by iron supplementation. CONCLUSIONS: Our findings suggest that impaired endocytosis and cargo transport resulting in subcellular iron deficiency could be a relevant pathomechanism for patients with DCM carrying inherited mutations. Insight into this molecular mechanism may contribute to the development of treatment strategies and risk management in heart failure.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Células-Tronco Pluripotentes Induzidas , Deficiências de Ferro , Humanos , Miócitos Cardíacos/metabolismo , Mutação , Cardiomiopatia Dilatada/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Ferro/metabolismo , Clatrina/genética , Clatrina/metabolismo , Clatrina/farmacologia
18.
Int J Mol Sci ; 24(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37373335

RESUMO

In heart failure and atrial fibrillation, a persistent Na+ current (INaL) exerts detrimental effects on cellular electrophysiology and can induce arrhythmias. We have recently shown that NaV1.8 contributes to arrhythmogenesis by inducing a INaL. Genome-wide association studies indicate that mutations in the SCN10A gene (NaV1.8) are associated with increased risk for arrhythmias, Brugada syndrome, and sudden cardiac death. However, the mediation of these NaV1.8-related effects, whether through cardiac ganglia or cardiomyocytes, is still a subject of controversial discussion. We used CRISPR/Cas9 technology to generate homozygous atrial SCN10A-KO-iPSC-CMs. Ruptured-patch whole-cell patch-clamp was used to measure the INaL and action potential duration. Ca2+ measurements (Fluo 4-AM) were performed to analyze proarrhythmogenic diastolic SR Ca2+ leak. The INaL was significantly reduced in atrial SCN10A KO CMs as well as after specific pharmacological inhibition of NaV1.8. No effects on atrial APD90 were detected in any groups. Both SCN10A KO and specific blockers of NaV1.8 led to decreased Ca2+ spark frequency and a significant reduction of arrhythmogenic Ca2+ waves. Our experiments demonstrate that NaV1.8 contributes to INaL formation in human atrial CMs and that NaV1.8 inhibition modulates proarrhythmogenic triggers in human atrial CMs and therefore NaV1.8 could be a new target for antiarrhythmic strategies.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Fibrilação Atrial/genética , Fibrilação Atrial/metabolismo , Estudo de Associação Genômica Ampla , Antiarrítmicos/farmacologia , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/metabolismo , Potenciais de Ação , Canal de Sódio Disparado por Voltagem NAV1.8/genética , Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo
19.
Int J Mol Sci ; 24(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37175421

RESUMO

Angiogenesis is the process of new blood vessels growing from existing vasculature. Visualizing them as a three-dimensional (3D) model is a challenging, yet relevant, task as it would be of great help to researchers, pathologists, and medical doctors. A branching analysis on the 3D model would further facilitate research and diagnostic purposes. In this paper, a pipeline of vision algorithms is elaborated to visualize and analyze blood vessels in 3D from formalin-fixed paraffin-embedded (FFPE) granulation tissue sections with two different staining methods. First, a U-net neural network is used to segment blood vessels from the tissues. Second, image registration is used to align the consecutive images. Coarse registration using an image-intensity optimization technique, followed by finetuning using a neural network based on Spatial Transformers, results in an excellent alignment of images. Lastly, the corresponding segmented masks depicting the blood vessels are aligned and interpolated using the results of the image registration, resulting in a visualized 3D model. Additionally, a skeletonization algorithm is used to analyze the branching characteristics of the 3D vascular model. In summary, computer vision and deep learning is used to reconstruct, visualize and analyze a 3D vascular model from a set of parallel tissue samples. Our technique opens innovative perspectives in the pathophysiological understanding of vascular morphogenesis under different pathophysiological conditions and its potential diagnostic role.


Assuntos
Imageamento Tridimensional , Redes Neurais de Computação , Imageamento Tridimensional/métodos , Algoritmos , Fenômenos Fisiológicos Cardiovasculares , Morfogênese , Processamento de Imagem Assistida por Computador
20.
Artigo em Inglês | MEDLINE | ID: mdl-37169875

RESUMO

Cardiovascular diseases (CVD) remain the leading cause of death worldwide and pharmacotherapy of most of them is suboptimal. Thus, there is a clear unmet clinical need to develop new pharmacological strategies with greater efficacy and better safety profiles. In this review, we summarize the most relevant advances in cardiovascular pharmacology in 2022 including the approval of first-in-class drugs that open new avenues for the treatment of obstructive hypertrophic cardiomyopathy (mavacamten), type 2 diabetes mellitus (tirzepatide), and heart failure (HF) independent of left ventricular ejection fraction (sodium-glucose cotransporter 2 inhibitors). We also dealt with fixed dose combination therapies repurposing different formulations of "old" drugs with well-known efficacy and safety for the treatment of patients with acute decompensated HF (acetazolamide plus loop diuretics), atherosclerotic cardiovascular disease (moderate-dose statin plus ezetimibe), Marfan syndrome (angiotensin receptor blockers plus ß-blockers), and secondary cardiovascular prevention (i.e. low-dose aspirin, ramipril and atorvastatin), thereby filling existing gaps in knowledge, and opening new avenues for the treatment of CVD. Clinical trials confirming the role of dapagliflozin in patients with HF and mildly reduced or preserved ejection fraction, long-term evolocumab to reduce the risk of cardiovascular events, vitamin K antagonists for stroke prevention in patients with rheumatic heart disease-associated atrial fibrillation, antibiotic prophylaxis in patients at high risk for infective endocarditis before invasive dental procedures, and vutrisiran for the treatment of hereditary transthyretin-related amyloidosis with polyneuropathy were also reviewed. Finally, we briefly discuss recent clinical trials suggesting that FXIa inhibitors may have the potential to uncouple thrombosis from hemostasis and attenuate/prevent thromboembolic events with minimal disruption of hemostasis.

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