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2.
Cell Genom ; 2(1)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35530816

RESUMO

Genetic studies on telomere length are important for understanding age-related diseases. Prior GWAS for leukocyte TL have been limited to European and Asian populations. Here, we report the first sequencing-based association study for TL across ancestrally-diverse individuals (European, African, Asian and Hispanic/Latino) from the NHLBI Trans-Omics for Precision Medicine (TOPMed) program. We used whole genome sequencing (WGS) of whole blood for variant genotype calling and the bioinformatic estimation of telomere length in n=109,122 individuals. We identified 59 sentinel variants (p-value <5×10-9) in 36 loci associated with telomere length, including 20 newly associated loci (13 were replicated in external datasets). There was little evidence of effect size heterogeneity across populations. Fine-mapping at OBFC1 indicated the independent signals colocalized with cell-type specific eQTLs for OBFC1 (STN1). Using a multi-variant gene-based approach, we identified two genes newly implicated in telomere length, DCLRE1B (SNM1B) and PARN. In PheWAS, we demonstrated our TL polygenic trait scores (PTS) were associated with increased risk of cancer-related phenotypes.

4.
BMC Genomics ; 23(1): 227, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35321643

RESUMO

BACKGROUND: Genetic variants have been found to influence red blood cell (RBC) susceptibility to hemolytic stress and affect transfusion outcomes and the severity of blood diseases. Males have a higher susceptibility to hemolysis than females, but little is known about the genetic mechanism contributing to the difference. RESULTS: To investigate the sex differences in RBC susceptibility to hemolysis, we conducted a sex-stratified genome-wide association study and a genome-wide gene-by-sex interaction scan in a multi-ethnic dataset with 12,231 blood donors who have in vitro osmotic hemolysis measurements during routine blood storage. The estimated SNP-based heritability for osmotic hemolysis was found to be significantly higher in males than in females (0.46 vs. 0.41). We identified SNPs associated with sex-specific susceptibility to osmotic hemolysis in five loci (SPTA1, KCNA6, SLC4A1, SUMO1P1, and PAX8) that impact RBC function and hemolysis. CONCLUSION: Our study established a best practice to identify sex-specific genetic modifiers for sexually dimorphic traits in datasets with mixed ancestries, providing evidence of different genetic regulations of RBC susceptibility to hemolysis between sexes. These and other variants may help explain observed sex differences in the severity of hemolytic diseases, such as sickle cell and malaria, as well as the viability of red cell storage and recovery.


Assuntos
Preservação de Sangue , Eritrócitos , Hemólise , Pressão Osmótica , Feminino , Estudo de Associação Genômica Ampla , Humanos , Canal de Potássio Kv1.6/genética , Masculino , Osmose , Fatores Sexuais
5.
Nitric Oxide ; 121: 11-19, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35124204

RESUMO

Nitric Oxide (NO) is an important signaling molecule that plays roles in controlling vascular tone, hemostasis, host defense, and many other physiological functions. Low NO bioavailability contributes to pathology and NO administration has therapeutic potential in a variety of diseases. Thus, accurate measurements of NO bioavailability and reactivity are critical. Due to its short lifetime in vivo and many in vitro conditions, NO bioavailability and reactivity are often best determined by measuring NO congeners and metabolites that are more stable. Chemiluminescence-based detection of NO following chemical reduction of these compounds using the tri-iodide and vanadium chloride methods have been widely used in a variety of clinical and laboratory studies. In this review, we describe these methods used to detect nitrite, nitrate, nitrosothiols and other species and discuss limitations and proper controls.


Assuntos
Cloretos/química , Iodetos/química , Medições Luminescentes , Óxidos de Nitrogênio/análise , Vanádio/química , Humanos
6.
J Clin Invest ; 132(4)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34990411

RESUMO

BACKGROUNDCurative gene therapies for sickle cell disease (SCD) are currently undergoing clinical evaluation. The occurrence of myeloid malignancies in these trials has prompted safety concerns. Individuals with SCD are predisposed to myeloid malignancies, but the underlying causes remain undefined. Clonal hematopoiesis (CH) is a premalignant condition that also confers significant predisposition to myeloid cancers. While it has been speculated that CH may play a role in SCD-associated cancer predisposition, limited data addressing this issue have been reported.METHODSHere, we leveraged 74,190 whole-genome sequences to robustly study CH in SCD. Somatic mutation calling methods were used to assess CH in all samples and comparisons between individuals with and without SCD were performed.RESULTSWhile we had sufficient power to detect a greater than 2-fold increased rate of CH, we found no detectable variation in rate or clone properties between individuals affected by SCD and controls. The rate of CH in individuals with SCD was unaltered by hydroxyurea use.CONCLUSIONSWe did not observe an increased risk for acquiring detectable CH in SCD, at least as measured by whole-genome sequencing. These results should help guide ongoing efforts and further studies that seek to better define the risk factors underlying myeloid malignancy predisposition in SCD and help ensure that curative therapies can be more safely applied.FUNDINGNew York Stem Cell Foundation and the NIH.


Assuntos
Anemia Falciforme/genética , Hematopoiese Clonal/genética , Anemia Falciforme/terapia , Feminino , Humanos , Masculino , Sequenciamento Completo do Genoma
7.
JCI Insight ; 7(1)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34793330

RESUMO

BACKGROUNDRBC transfusion effectiveness varies due to donor, component, and recipient factors. Prior studies identified characteristics associated with variation in hemoglobin increments following transfusion. We extended these observations, examining donor genetic and nongenetic factors affecting transfusion effectiveness.METHODSThis is a multicenter retrospective study of 46,705 patients and 102,043 evaluable RBC transfusions from 2013 to 2016 across 12 hospitals. Transfusion effectiveness was defined as hemoglobin, bilirubin, or creatinine increments following single RBC unit transfusion. Models incorporated a subset of donors with data on single nucleotide polymorphisms associated with osmotic and oxidative hemolysis in vitro. Mixed modeling accounting for repeated transfusion episodes identified predictors of transfusion effectiveness.RESULTSBlood donor (sex, Rh status, fingerstick hemoglobin, smoking), component (storage duration, γ irradiation, leukoreduction, apheresis collection, storage solution), and recipient (sex, BMI, race and ethnicity, age) characteristics were associated with hemoglobin and bilirubin, but not creatinine, increments following RBC transfusions. Increased storage duration was associated with increased bilirubin and decreased hemoglobin increments, suggestive of in vivo hemolysis following transfusion. Donor G6PD deficiency and polymorphisms in SEC14L4, HBA2, and MYO9B genes were associated with decreased hemoglobin increments. Donor G6PD deficiency and polymorphisms in SEC14L4 were associated with increased transfusion requirements in the subsequent 48 hours.CONCLUSIONDonor genetic and other factors, such as RBC storage duration, affect transfusion effectiveness as defined by decreased hemoglobin or increased bilirubin increments. Addressing these factors will provide a precision medicine approach to improve patient outcomes, particularly for chronically transfused RBC recipients, who would most benefit from more effective transfusion products.FUNDINGFunding was provided by HHSN 75N92019D00032, HHSN 75N92019D00034, 75N92019D00035, HHSN 75N92019D00036, and HHSN 75N92019D00037; R01HL126130; and the National Institute of Child Health and Human Development (NICHD).


Assuntos
Doadores de Sangue/estatística & dados numéricos , Transfusão de Eritrócitos , Adulto , Idoso , Transfusão de Eritrócitos/normas , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Hemoglobinas/análise , Hemólise , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Am J Hematol ; 96(12): 1630-1638, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626431

RESUMO

The six-minute walk test (6MWT) has been used in patients with sickle cell disease (SCD), in conjunction with tricuspid regurgitant velocity (TRV) and plasma N-terminal pro-brain natriuretic peptide (NT-pro BNP), to assess risk of having pulmonary hypertension. Exercise-induced vital sign changes (VSCs) are predictors of clinical outcomes in other diseases. In this study, we assess the predictors and prognostic value of 6MWT VSC in adult SCD patients. Data from a multinational study of SCD patients (Treatment of Pulmonary Hypertension with Sildenafil: walk-PHaSST) were used to calculate the 6MWT VSC. Predictors of VSC were identified by a multivariable analysis, and a survival analysis was conducted by the Cox proportional hazard method. An increase in heart rate was observed in 90% of the 630 SCD adults, 77% of patients had an increase in systolic blood pressure (SBP), and 50% of patients had a decrease in oxygen saturation. TRV (odds ratio [OR] = 1.82, p = .020), absolute reticulocyte count (OR = 1.03, p < .001), and hemoglobin (OR = 0.99, p = .035) predicted oxygen desaturation ≥ 3% during the 6MWT. In the adjusted analysis, SBP increase during the 6MWT was associated with improved survival (hazards ratio = 0.3, 95% confidence interval: 0.1-0.8). Increases in heart rate and blood pressure, as well as oxygen desaturation, are common in adults with SCD during the 6MWT. VSC is associated with markers of anemia and TRV and can be used for risk stratification. Any increase in SBP during the 6MWT was associated with improved survival and may be indicative of a patient's ability to increase stroke volume.


Assuntos
Anemia Falciforme/terapia , Terapia por Exercício , Hipertensão Pulmonar/terapia , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico , Anemia Falciforme/fisiopatologia , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Análise de Sobrevida , Sinais Vitais , Caminhada
10.
Circ Heart Fail ; 14(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34422205

RESUMO

Right ventricular dysfunction is a hallmark of advanced pulmonary vascular, lung parenchymal, and left heart disease, yet the underlying mechanisms that govern (mal)adaptation remain incompletely characterized. Owing to the knowledge gaps in our understanding of the right ventricle (RV) in health and disease, the National Heart, Lung, and Blood Institute (NHLBI) commissioned a working group to identify current challenges in the field. These included a need to define and standardize normal RV structure and function in populations; access to RV tissue for research purposes and the development of complex experimental platforms that recapitulate the in vivo environment; and the advancement of imaging and invasive methodologies to study the RV within basic, translational, and clinical research programs. Specific recommendations were provided, including a call to incorporate precision medicine and innovations in prognosis, diagnosis, and novel RV therapeutics for patients with pulmonary vascular disease.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Hipertensão Pulmonar/terapia , Circulação Pulmonar/fisiologia , Função Ventricular Direita/imunologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , National Heart, Lung, and Blood Institute (U.S.) , Estados Unidos , Disfunção Ventricular Direita/fisiopatologia
11.
Inorg Chem ; 60(21): 15918-15940, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34313417

RESUMO

Interdisciplinary research at the interface of chemistry, physiology, and biomedicine have uncovered pivotal roles of nitric oxide (NO) as a signaling molecule that regulates vascular tone, platelet aggregation, and other pathways relevant to human health and disease. Heme is central to physiological NO signaling, serving as the active site for canonical NO biosynthesis in nitric oxide synthase (NOS) enzymes and as the highly selective NO binding site in the soluble guanylyl cyclase receptor. Outside of the primary NOS-dependent biosynthetic pathway, other hemoproteins, including hemoglobin and myoglobin, generate NO via the reduction of nitrite. This auxiliary hemoprotein reaction unlocks a "second axis" of NO signaling in which nitrite serves as a stable NO reservoir. In this Forum Article, we highlight these NO-dependent physiological pathways and examine complex chemical and biochemical reactions that govern NO and nitrite signaling in vivo. We focus on hemoprotein-dependent reaction pathways that generate and consume NO in the presence of nitrite and consider intermediate nitrogen oxides, including NO2, N2O3, and S-nitrosothiols, that may facilitate nitrite-based signaling in blood vessels and tissues. We also discuss emergent therapeutic strategies that leverage our understanding of these key reaction pathways to target NO signaling and treat a wide range of diseases.


Assuntos
Óxido Nítrico
12.
Front Cardiovasc Med ; 8: 668222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295927

RESUMO

Pulmonary arterial hypertension (PAH) leads to right ventricular cardiomyopathy and cardiac dysfunctions where in the clinical setting, cardiac arrest is the likely cause of death, in ~70% of PAH patients. We investigated the cardiac phenotype of PAH hearts and tested the hypothesis that the insulin-like hormone, Relaxin could prevent maladaptive cardiac remodeling and protect against cardiac dysfunctions in a PAH animal model. PAH was induced in rats with sugen (20 mg/kg), hypoxia then normoxia (3-weeks/each); relaxin (RLX = 0, 30 or 400 µg/kg/day, n ≥ 6/group) was delivered subcutaneously (6-weeks) with implanted osmotic mini-pumps. Right ventricle (RV) hemodynamics and Doppler-flow measurements were followed by cardiac isolation, optical mapping, and arrhythmia phenotype. Sugen-hypoxia (SuHx) treated rats developed PAH characterized by higher RV systolic pressures (50 ± 19 vs. 22 ± 5 mmHg), hypertrophy, reduced stroke volume, ventricular fibrillation (VF) (n = 6/11) and bradycardia/arrest (n = 5/11); both cardiac phenotypes were suppressed with dithiothreitol (DTT = 1 mM) (n = 0/2/group) or RLX (low or high dose, n = 0/6/group). PAH hearts developed increased fibrosis that was reversed by RLX-HD, but not RLX-LD. Relaxin decreased Nrf2 and glutathione transferases but not glutathione-reductase. High-dose RLX improved pulmonary arterial compliance (measured by Doppler flow), suppressed VF even after burst-pacing, n = 2/6). Relaxin suppressed VF and asystole through electrical remodeling and by reversing thiol oxidative stress. For the first time, we showed two cardiac phenotypes in PAH animals and their prevention by RLX. Relaxin may modulate maladaptive cardiac remodeling in PAH and protect against arrhythmia and cardiac arrest.

13.
Circulation ; 144(8): 615-637, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34157861

RESUMO

BACKGROUND: Many patients with heart failure with preserved ejection fraction have metabolic syndrome and develop exercise-induced pulmonary hypertension (EIPH). Increases in pulmonary vascular resistance in patients with heart failure with preserved ejection fraction portend a poor prognosis; this phenotype is referred to as combined precapillary and postcapillary pulmonary hypertension (CpcPH). Therapeutic trials for EIPH and CpcPH have been disappointing, suggesting the need for strategies that target upstream mechanisms of disease. This work reports novel rat EIPH models and mechanisms of pulmonary vascular dysfunction centered around the transcriptional repression of the soluble guanylate cyclase (sGC) enzyme in pulmonary artery (PA) smooth muscle cells. METHODS: We used obese ZSF-1 leptin-receptor knockout rats (heart failure with preserved ejection fraction model), obese ZSF-1 rats treated with SU5416 to stimulate resting pulmonary hypertension (obese+sugen, CpcPH model), and lean ZSF-1 rats (controls). Right and left ventricular hemodynamics were evaluated using implanted catheters during treadmill exercise. PA function was evaluated with magnetic resonance imaging and myography. Overexpression of nuclear factor Y α subunit (NFYA), a transcriptional enhancer of sGC ß1 subunit (sGCß1), was performed by PA delivery of adeno-associated virus 6. Treatment groups received the SGLT2 inhibitor empagliflozin in drinking water. PA smooth muscle cells from rats and humans were cultured with palmitic acid, glucose, and insulin to induce metabolic stress. RESULTS: Obese rats showed normal resting right ventricular systolic pressures, which significantly increased during exercise, modeling EIPH. Obese+sugen rats showed anatomic PA remodeling and developed elevated right ventricular systolic pressure at rest, which was exacerbated with exercise, modeling CpcPH. Myography and magnetic resonance imaging during dobutamine challenge revealed PA functional impairment of both obese groups. PAs of obese rats produced reactive oxygen species and decreased sGCß1 expression. Mechanistically, cultured PA smooth muscle cells from obese rats and humans with diabetes or treated with palmitic acid, glucose, and insulin showed increased mitochondrial reactive oxygen species, which enhanced miR-193b-dependent RNA degradation of nuclear factor Y α subunit (NFYA), resulting in decreased sGCß1-cGMP signaling. Forced NYFA expression by adeno-associated virus 6 delivery increased sGCß1 levels and improved exercise pulmonary hypertension in obese+sugen rats. Treatment of obese+sugen rats with empagliflozin improved metabolic syndrome, reduced mitochondrial reactive oxygen species and miR-193b levels, restored NFYA/sGC activity, and prevented EIPH. CONCLUSIONS: In heart failure with preserved ejection fraction and CpcPH models, metabolic syndrome contributes to pulmonary vascular dysfunction and EIPH through enhanced reactive oxygen species and miR-193b expression, which downregulates NFYA-dependent sGCß1 expression. Adeno-associated virus-mediated NFYA overexpression and SGLT2 inhibition restore NFYA-sGCß1-cGMP signaling and ameliorate EIPH.


Assuntos
Fator de Ligação a CCAAT/metabolismo , Insuficiência Cardíaca/etiologia , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/etiologia , Síndrome Metabólica/genética , Síndrome Metabólica/metabolismo , MicroRNAs/genética , Espécies Reativas de Oxigênio/metabolismo , Guanilil Ciclase Solúvel/genética , Animais , Animais Geneticamente Modificados , Biomarcadores , Modelos Animais de Doenças , Suscetibilidade a Doenças , Exercício Físico , Regulação da Expressão Gênica , Insuficiência Cardíaca/diagnóstico , Humanos , Síndrome Metabólica/complicações , Mitocôndrias Cardíacas , Miócitos de Músculo Liso/metabolismo , Fenótipo , Ratos , Transdução de Sinais , Estresse Fisiológico , Volume Sistólico , Disfunção Ventricular Direita
14.
J Clin Invest ; 131(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34014839

RESUMO

BackgroundThe evolutionary pressure of endemic malaria and other erythrocytic pathogens has shaped variation in genes encoding erythrocyte structural and functional proteins, influencing responses to hemolytic stress during transfusion and disease.MethodsWe sought to identify such genetic variants in blood donors by conducting a genome-wide association study (GWAS) of 12,353 volunteer donors, including 1,406 African Americans, 1,306 Asians, and 945 Hispanics, whose stored erythrocytes were characterized by quantitative assays of in vitro osmotic, oxidative, and cold-storage hemolysis.ResultsGWAS revealed 27 significant loci (P < 5 × 10-8), many in candidate genes known to modulate erythrocyte structure, metabolism, and ion channels, including SPTA1, ALDH2, ANK1, HK1, MAPKAPK5, AQP1, PIEZO1, and SLC4A1/band 3. GWAS of oxidative hemolysis identified variants in genes encoding antioxidant enzymes, including GLRX, GPX4, G6PD, and SEC14L4 (Golgi-transport protein). Genome-wide significant loci were also tested for association with the severity of steady-state (baseline) in vivo hemolytic anemia in patients with sickle cell disease, with confirmation of identified SNPs in HBA2, G6PD, PIEZO1, AQP1, and SEC14L4.ConclusionsMany of the identified variants, such as those in G6PD, have previously been shown to impair erythrocyte recovery after transfusion, associate with anemia, or cause rare Mendelian human hemolytic diseases. Candidate SNPs in these genes, especially in polygenic combinations, may affect RBC recovery after transfusion and modulate disease severity in hemolytic diseases, such as sickle cell disease and malaria.


Assuntos
Preservação de Sangue/efeitos adversos , Preservação de Sangue/métodos , Eritrócitos/metabolismo , Hemólise/genética , Polimorfismo de Nucleotídeo Único , Adulto , Afro-Americanos/genética , Americanos Asiáticos/genética , Doadores de Sangue , Estudos de Coortes , Temperatura Baixa , Transfusão de Eritrócitos/efeitos adversos , Evolução Molecular , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Técnicas In Vitro , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Pressão Osmótica , Estresse Oxidativo , Adulto Jovem
15.
Am J Physiol Heart Circ Physiol ; 320(6): H2385-H2400, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33989079

RESUMO

Cell-free hemoglobin (CFH) levels are elevated in septic shock and are higher in nonsurvivors. Whether CFH is only a marker of sepsis severity or is involved in pathogenesis is unknown. This study aimed to investigate whether CFH worsens sepsis-associated injuries and to determine potential mechanisms of harm. Fifty-one, 10-12 kg purpose-bred beagles were randomized to receive Staphylococcus aureus intrapulmonary challenges or saline followed by CFH infusions (oxyhemoglobin >80%) or placebo. Animals received antibiotics and intensive care support for 96 h. CFH significantly increased mean pulmonary arterial pressures and right ventricular afterload in both septic and nonseptic animals, effects that were significantly greater in nonsurvivors. These findings are consistent with CFH-associated nitric oxide (NO) scavenging and were associated with significantly depressed cardiac function, and worsened shock, lactate levels, metabolic acidosis, and multiorgan failure. In septic animals only, CFH administration significantly increased mean alveolar-arterial oxygenation gradients, also to a significantly greater degree in nonsurvivors. CFH-associated iron levels were significantly suppressed in infected animals, suggesting that bacterial iron uptake worsened pneumonia. Notably, cytokine levels were similar in survivors and nonsurvivors and were not predictive of outcome. In the absence and presence of infection, CFH infusions resulted in pulmonary hypertension, cardiogenic shock, and multiorgan failure, likely through NO scavenging. In the presence of infection alone, CFH infusions worsened oxygen exchange and lung injury, presumably by supplying iron that promoted bacterial growth. CFH elevation, a known consequence of clinical septic shock, adversely impacts sepsis outcomes through more than one mechanism, and is a biologically plausible, nonantibiotic, noncytokine target for therapeutic intervention.NEW & NOTEWORTHY Cell-free hemoglobin (CFH) elevations are a known consequence of clinical sepsis. Using a two-by-two factorial design and extensive physiological and biochemical evidence, we found a direct mechanism of injury related to nitric oxide scavenging leading to pulmonary hypertension increasing right heart afterload, depressed cardiac function, worsening circulatory failure, and death, as well as an indirect mechanism related to iron toxicity. These discoveries alter conventional thinking about septic shock pathogenesis and provide novel therapeutic approaches.


Assuntos
Hemoglobinas/metabolismo , Pneumonia/metabolismo , Artéria Pulmonar/fisiopatologia , Choque Séptico/metabolismo , Infecções Estafilocócicas/metabolismo , Acidose/metabolismo , Acidose/fisiopatologia , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/fisiopatologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Cães , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Hemoglobinas/farmacologia , Ferro/metabolismo , Ácido Láctico/metabolismo , Insuficiência de Múltiplos Órgãos/metabolismo , Insuficiência de Múltiplos Órgãos/fisiopatologia , Óxido Nítrico/metabolismo , Pneumonia/fisiopatologia , Troca Gasosa Pulmonar , Distribuição Aleatória , Choque Séptico/fisiopatologia , Staphylococcus aureus/crescimento & desenvolvimento
18.
J Clin Invest ; 131(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33905372

RESUMO

The dynamic regulation of endothelial pathophenotypes in pulmonary hypertension (PH) remains undefined. Cellular senescence is linked to PH with intracardiac shunts; however, its regulation across PH subtypes is unknown. Since endothelial deficiency of iron-sulfur (Fe-S) clusters is pathogenic in PH, we hypothesized that a Fe-S biogenesis protein, frataxin (FXN), controls endothelial senescence. An endothelial subpopulation in rodent and patient lungs across PH subtypes exhibited reduced FXN and elevated senescence. In vitro, hypoxic and inflammatory FXN deficiency abrogated activity of endothelial Fe-S-containing polymerases, promoting replication stress, DNA damage response, and senescence. This was also observed in stem cell-derived endothelial cells from Friedreich's ataxia (FRDA), a genetic disease of FXN deficiency, ataxia, and cardiomyopathy, often with PH. In vivo, FXN deficiency-dependent senescence drove vessel inflammation, remodeling, and PH, whereas pharmacologic removal of senescent cells in Fxn-deficient rodents ameliorated PH. These data offer a model of endothelial biology in PH, where FXN deficiency generates a senescent endothelial subpopulation, promoting vascular inflammatory and proliferative signals in other cells to drive disease. These findings also establish an endothelial etiology for PH in FRDA and left heart disease and support therapeutic development of senolytic drugs, reversing effects of Fe-S deficiency across PH subtypes.


Assuntos
Senescência Celular/genética , Endotélio Vascular/metabolismo , Ataxia de Friedreich , Hipertensão Pulmonar , Proteínas de Ligação ao Ferro/genética , Remodelação Vascular/genética , Animais , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Endotélio Vascular/patologia , Feminino , Ataxia de Friedreich/genética , Ataxia de Friedreich/metabolismo , Ataxia de Friedreich/patologia , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Proteínas de Ligação ao Ferro/metabolismo , Masculino , Camundongos , Camundongos Knockout
19.
Circulation ; 143(16): e836-e870, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33682423

RESUMO

Opioid overdose is the leading cause of death for Americans 25 to 64 years of age, and opioid use disorder affects >2 million Americans. The epidemiology of opioid-associated out-of-hospital cardiac arrest in the United States is changing rapidly, with exponential increases in death resulting from synthetic opioids and linear increases in heroin deaths more than offsetting modest reductions in deaths from prescription opioids. The pathophysiology of polysubstance toxidromes involving opioids, asphyxial death, and prolonged hypoxemia leading to global ischemia (cardiac arrest) differs from that of sudden cardiac arrest. People who use opioids may also develop bacteremia, central nervous system vasculitis and leukoencephalopathy, torsades de pointes, pulmonary vasculopathy, and pulmonary edema. Emergency management of opioid poisoning requires recognition by the lay public or emergency dispatchers, prompt emergency response, and effective ventilation coupled to compressions in the setting of opioid-associated out-of-hospital cardiac arrest. Effective ventilation is challenging to teach, whereas naloxone, an opioid antagonist, can be administered by emergency medical personnel, trained laypeople, and the general public with dispatcher instruction to prevent cardiac arrest. Opioid education and naloxone distributions programs have been developed to teach people who are likely to encounter a person with opioid poisoning how to administer naloxone, deliver high-quality compressions, and perform rescue breathing. Current American Heart Association recommendations call for laypeople and others who cannot reliably establish the presence of a pulse to initiate cardiopulmonary resuscitation in any individual who is unconscious and not breathing normally; if opioid overdose is suspected, naloxone should also be administered. Secondary prevention, including counseling, opioid overdose education with take-home naloxone, and medication for opioid use disorder, is important to prevent recurrent opioid overdose.


Assuntos
Analgésicos Opioides/efeitos adversos , Serviços Médicos de Emergência/normas , Parada Cardíaca Extra-Hospitalar/induzido quimicamente , American Heart Association , Humanos , Fatores de Risco , Estados Unidos
20.
PLoS One ; 16(2): e0243274, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33621231

RESUMO

BACKGROUND: People living with human immunodeficiency virus (PLWH) are at risk of developing pulmonary hypertension (PH) and right ventricular (RV) dysfunction, but understanding of the relationship of RV function to afterload (RV-PA coupling) is limited. We evaluated the clinical and hemodynamic characteristics of human immunodeficiency virus (HIV)-associated PH. METHODS: We performed a retrospective review of patients with a diagnosis of HIV undergoing right heart catheterization (RHC) from 2000-2016 in a tertiary care center. Inclusion criteria were diagnosis of HIV, age ≥ 18 years and availability of RHC data. PH was classified as either pulmonary arterial hypertension (PAH; mean pulmonary arterial pressure [mPAP] ≥ 25mmHg with pulmonary artery wedge pressure [PAWP] ≤ 15mmHg) or pulmonary venous hypertension (PVH; mPAP ≥ 25mmHg with PAWP > 15). We collected demographics, CD4 cell count, HIV viral load, RHC and echocardiographic data. The single beat method was used to calculate RV-PA coupling from RHC. RESULTS: Sixty-two PLWH with a clinical likelihood for PH underwent RHC. Thirty-two (52%) met PH criteria (15 with PAH, 17 with PVH). Average time from diagnosis of HIV to diagnosis of PH was 11 years. Eleven of 15 individuals with PAH were on antiretroviral therapy (ART) while all 17 patients with PVH were on ART. Compared to PLWH without PH, those with PH had an increased likelihood of having a detectable HIV viral load and lower CD4 cell counts. PLWH with PAH or PVH had increased RV afterload with normal RV contractility, and preserved RV-PA coupling. CONCLUSION: PLWH with PH (PAH or PVH) were more likely to have a detectable HIV viral load and lower CD4 count at the time of RHC. PLWH with PAH or PVH had increased RV afterload, normal RV contractility, with preserved RV-PA coupling suggestive of an early onset, mild, and compensated form of PH. These results should be confirmed in larger studies.


Assuntos
Infecções por HIV/complicações , Hipertensão Pulmonar/etiologia , Disfunção Ventricular Direita/etiologia , Adulto , Cateterismo Cardíaco , Feminino , HIV/isolamento & purificação , Infecções por HIV/diagnóstico , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/virologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Hipertensão Arterial Pulmonar/diagnóstico , Hipertensão Arterial Pulmonar/etiologia , Hipertensão Arterial Pulmonar/fisiopatologia , Hipertensão Arterial Pulmonar/virologia , Estudos Retrospectivos , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/fisiopatologia , Disfunção Ventricular Direita/virologia , Carga Viral
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