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1.
J Card Fail ; 30(9): 1136-1153, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38777216

RESUMO

For many years, treatment of hypertrophic cardiomyopathy (HCM) has focused on non-disease-specific therapies. Cardiac myosin modulators (ie, mavacamten and aficamten) reduce the pathologic actin-myosin interactions that are characteristic of HCM, leading to improved cardiac energetics and reduction in hypercontractility. Several recently published randomized clinical trials have demonstrated that mavacamten improves exercise capacity, left ventricular outflow tract obstruction and symptoms in patients with obstructive HCM and may delay the need for septal-reduction therapy. Long-term data in real-world populations will be needed to fully assess the safety and efficacy of mavacamten. Importantly, HCM is a complex and heterogeneous disease, and not all patients will respond to mavacamten; therefore, careful patient selection and shared decision making will be necessary in guiding the use of mavacamten in obstructive HCM.


Assuntos
Cardiomiopatia Hipertrófica , Gerenciamento Clínico , Humanos , Cardiomiopatia Hipertrófica/terapia , Cardiomiopatia Hipertrófica/fisiopatologia , Benzilaminas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Resultado do Tratamento , Uracila/análogos & derivados
2.
Circulation ; 145(16): 1238-1253, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35384713

RESUMO

BACKGROUND: Familial hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease and is typically caused by mutations in genes encoding sarcomeric proteins that regulate cardiac contractility. HCM manifestations include left ventricular hypertrophy and heart failure, arrythmias, and sudden cardiac death. How dysregulated sarcomeric force production is sensed and leads to pathological remodeling remains poorly understood in HCM, thereby inhibiting the efficient development of new therapeutics. METHODS: Our discovery was based on insights from a severe phenotype of an individual with HCM and a second genetic alteration in a sarcomeric mechanosensing protein. We derived cardiomyocytes from patient-specific induced pluripotent stem cells and developed robust engineered heart tissues by seeding induced pluripotent stem cell-derived cardiomyocytes into a laser-cut scaffold possessing native cardiac fiber alignment to study human cardiac mechanobiology at both the cellular and tissue levels. Coupled with computational modeling for muscle contraction and rescue of disease phenotype by gene editing and pharmacological interventions, we have identified a new mechanotransduction pathway in HCM, shown to be essential in modulating the phenotypic expression of HCM in 5 families bearing distinct sarcomeric mutations. RESULTS: Enhanced actomyosin crossbridge formation caused by sarcomeric mutations in cardiac myosin heavy chain (MYH7) led to increased force generation, which, when coupled with slower twitch relaxation, destabilized the MLP (muscle LIM protein) stretch-sensing complex at the Z-disc. Subsequent reduction in the sarcomeric muscle LIM protein level caused disinhibition of calcineurin-nuclear factor of activated T-cells signaling, which promoted cardiac hypertrophy. We demonstrate that the common muscle LIM protein-W4R variant is an important modifier, exacerbating the phenotypic expression of HCM, but alone may not be a disease-causing mutation. By mitigating enhanced actomyosin crossbridge formation through either genetic or pharmacological means, we alleviated stress at the Z-disc, preventing the development of hypertrophy associated with sarcomeric mutations. CONCLUSIONS: Our studies have uncovered a novel biomechanical mechanism through which dysregulated sarcomeric force production is sensed and leads to pathological signaling, remodeling, and hypertrophic responses. Together, these establish the foundation for developing innovative mechanism-based treatments for HCM that stabilize the Z-disc MLP-mechanosensory complex.


Assuntos
Cardiomiopatia Hipertrófica Familiar , Cardiomiopatia Hipertrófica , Actomiosina/genética , Humanos , Proteínas com Domínio LIM , Mecanotransdução Celular , Proteínas Musculares , Mutação , Miócitos Cardíacos
3.
Curr Cardiol Rep ; 25(3): 171-184, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36897483

RESUMO

PURPOSE OF REVIEW: Cardiac consequences occur in both acute COVID-19 and post-acute sequelae of COVID-19 (PASC). Here, we highlight the current understanding about COVID-19 cardiac effects, based upon clinical, imaging, autopsy, and molecular studies. RECENT FINDINGS: COVID-19 cardiac effects are heterogeneous. Multiple, concurrent cardiac histopathologic findings have been detected on autopsies of COVID-19 non-survivors. Microthrombi and cardiomyocyte necrosis are commonly detected. Macrophages often infiltrate the heart at high density but without fulfilling histologic criteria for myocarditis. The high prevalences of microthrombi and inflammatory infiltrates in fatal COVID-19 raise the concern that recovered COVID-19 patients may have similar but subclinical cardiac pathology. Molecular studies suggest that SARS-CoV-2 infection of cardiac pericytes, dysregulated immunothrombosis, and pro-inflammatory and anti-fibrinolytic responses underlie COVID-19 cardiac pathology. The extent and nature by which mild COVID-19 affects the heart is unknown. Imaging and epidemiologic studies of recovered COVID-19 patients suggest that even mild illness confers increased risks of cardiac inflammation, cardiovascular disorders, and cardiovascular death. The mechanistic details of COVID-19 cardiac pathophysiology remain under active investigation. The ongoing evolution of SARS-CoV-2 variants and vast numbers of recovered COVID-19 patients portend a burgeoning global cardiovascular disease burden. Our ability to prevent and treat cardiovascular disease in the future will likely depend on comprehensive understanding of COVID-19 cardiac pathophysiologic phenotypes.


Assuntos
COVID-19 , Cardiopatias , Miocardite , Trombose , Humanos , COVID-19/complicações , COVID-19/epidemiologia , SARS-CoV-2/genética , Coração/diagnóstico por imagem , Miocardite/etiologia , Cardiopatias/complicações , Trombose/complicações
4.
J Mol Cell Cardiol ; 158: 11-25, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33992697

RESUMO

We have created a novel in-vitro platform to study reverse remodeling of engineered heart tissue (EHT) after mechanical unloading. EHTs were created by seeding decellularized porcine myocardial sections with a mixture of primary neonatal rat ventricular myocytes and cardiac fibroblasts. Each end of the ribbon-like constructs was fixed to a plastic clip, allowing the tissues to be statically stretched or slackened. Inelastic deformation was introduced by stretching tissues by 20% of their original length. EHTs were subsequently unloaded by returning tissues to their original, shorter length. Mechanical characterization of EHTs immediately after unloading and at subsequent time points confirmed the presence of a reverse-remodeling process, through which stress-free tissue length was increased after chronic stretch but gradually decreased back to its original value within 9 days. When a cardiac myosin inhibitor was applied to tissues after unloading, EHTs failed to completely recover their passive and active mechanical properties, suggesting a role for actomyosin contraction in reverse remodeling. Selectively inhibiting cardiomyocyte contraction or fibroblast activity after mechanical unloading showed that contractile activity of both cell types was required to achieve full remodeling. Similar tests with EHTs formed from human induced pluripotent stem cell-derived cardiomyocytes also showed reverse remodeling that was enhanced when treated with omecamtiv mecarbil, a myosin activator. These experiments suggest essential roles for active sarcomeric contraction and fibroblast activity in reverse remodeling of myocardium after mechanical unloading. Our findings provide a mechanistic rationale for designing potential therapies to encourage reverse remodeling in patient hearts.


Assuntos
Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , Sarcômeros/metabolismo , Transdução de Sinais/efeitos dos fármacos , Engenharia Tecidual/métodos , Remodelação Ventricular/efeitos dos fármacos , Actomiosina/metabolismo , Animais , Animais Recém-Nascidos , Benzamidas/farmacologia , Benzilaminas/farmacologia , Miosinas Cardíacas/antagonistas & inibidores , Miosinas Cardíacas/metabolismo , Linhagem Celular , Dioxóis/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Miofibroblastos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I/antagonistas & inibidores , Suínos , Alicerces Teciduais , Uracila/análogos & derivados , Uracila/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia
5.
Am J Physiol Heart Circ Physiol ; 320(3): H1112-H1123, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33449850

RESUMO

Comprehensive functional characterization of cardiac tissue includes investigation of length and load dependence. Such measurements have been slow to develop in engineered heart tissues (EHTs), whose mechanical characterizations have been limited primarily to isometric and near-isometric behaviors. A more realistic assessment of myocardial function would include force-velocity curves to characterize power output and force-length loops mimicking the cardiac cycle to characterize work output. We developed a system that produces force-velocity curves and work loops in human EHTs using an adaptive iterative control scheme. We used human EHTs in this system to perform a detailed characterization of the cardiac ß-myosin specific inhibitor, mavacamten. Consistent with the clinically proposed application of this drug to treat hypertrophic cardiomyopathy, our data support the premise that mavacamten improves diastolic function through reduction of diastolic stiffness and isometric relaxation time. Meanwhile, the effects of mavacamten on length- and load-dependent muscle performance were mixed. The drug attenuated the length-dependent response at small stretch values but showed normal length dependency at longer lengths. Peak power output of mavacamten-treated EHTs showed reduced power output as expected but also shifted peak power output to a lower load. Here, we demonstrate a robust method for the generation of isotonic contraction series and work loops in engineered heart tissues using an adaptive-iterative method. This approach reveals new features of mavacamten pharmacology, including previously unappreciated effects on intrinsic myosin dynamics and preservation of Frank-Starling behavior at longer muscle lengths.NEW & NOTEWORTHY We applied innovative methods to comprehensively characterize the length and load-dependent behaviors of engineered human cardiac muscle when treated with the cardiac ß-myosin specific inhibitor mavacamten, a drug on the verge of clinical implementation for hypertrophic cardiomyopathy. We find mechanistic support for the role of mavacamten in improving diastolic function of cardiac tissue and note novel effects on work and power.


Assuntos
Benzilaminas/farmacologia , Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Engenharia Tecidual , Uracila/análogos & derivados , Função Ventricular/efeitos dos fármacos , Miosinas Ventriculares/antagonistas & inibidores , Animais , Linhagem Celular , Diástole , Humanos , Modelos Cardiovasculares , Força Muscular/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Sus scrofa , Técnicas de Cultura de Tecidos , Alicerces Teciduais , Uracila/farmacologia , Miosinas Ventriculares/metabolismo
6.
Eur J Clin Invest ; 51(7): e13533, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33666941

RESUMO

BACKGROUND: The relationship between anticardiolipin (aCL) antibodies and cardiovascular events is uncertain and may vary according to arterial location. MATERIALS AND METHODS: FRENA is an ongoing registry of stable outpatients with symptomatic coronary artery disease (CAD), cerebrovascular disease (CVD) or peripheral artery disease (PAD). The rate of subsequent ischaemic events was cross-referenced with the presence of aCL antibodies (any isotype, IgG or IgM). RESULTS: As of June 2017, 1387 stable outpatients were recruited. Of these, 120 (8.7%) showed positive levels of aCL antibodies. Over an average follow-up of 18 months, 250 patients developed subsequent events: 101 myocardial infarction, 57 ischaemic stroke and 92 critical leg events. Patients with positive aCL antibodies had a higher risk of distal artery events (a composite of ischaemic stroke or critical leg events) than patients with undetectable or low levels (rate ratio: 1.66; 95% CI: 1.07-2.60). However, an association with central coronary events was not found. The multivariate Cox analysis after adjustment for relevant clinical covariates showed that positivity of aCL antibodies is an independent risk factor for distal events (hazard ratio: 1.60; 95% CI: 1.01-2.55; P < .05). CONCLUSIONS: Positivity of aCL antibodies is associated with an increased risk of subsequent distal artery ischaemic events (cerebral or leg arteries) but not coronary artery events. Anticardiolipin antibodies appear to have a different relationship on the localisation of ischaemic events in patients with symptomatic artery disease.


Assuntos
Anticorpos Anticardiolipina/imunologia , Transtornos Cerebrovasculares/imunologia , Doença da Artéria Coronariana/imunologia , AVC Isquêmico/imunologia , Infarto do Miocárdio/imunologia , Doença Arterial Periférica/imunologia , Idoso , Feminino , Humanos , Isquemia/epidemiologia , Isquemia/imunologia , AVC Isquêmico/epidemiologia , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/epidemiologia , Modelos de Riscos Proporcionais , Recidiva , Sistema de Registros
7.
Arch Biochem Biophys ; 697: 108711, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33271148

RESUMO

Substantial variation in relaxation rate exists among cardiomyocytes within small volumes of myocardium; however, it is unknown how this variability affects the overall relaxation mechanics of heart muscle. In this study, we sought to modulate levels of cellular heterogeneity in a computational model, then validate those predictions using an engineered heart tissue platform. We formulated an in silico tissue model composed of half-sarcomeres with varied relaxation rates, incorporating single-cell cardiomyocyte experimental data. These model tissues randomly sampled relaxation parameters from two offset distributions of fast- and slow-relaxing populations of half-sarcomeres. Isometric muscle twitch simulations predicted a complex relationship between relaxation time and the proportion of fast-versus slow-relaxing cells in heterogeneous tissues. Specifically, a 50/50 mixture of fast and slow cells did not lead to relaxation time that was the mean of the relaxation times associated with the two pure cases. Rather, the mean relaxation time was achieved at a ratio of 70:30 slow:fast relaxing cells, suggesting a disproportionate impact of fast-relaxing cells on overall tissue relaxation. To examine whether this behavior persists in vitro, we constructed engineered heart tissues from two lines of fast- and slow-relaxing human iPSC-derived cardiomyocytes. Cell tracking via fluorescent nanocrystals confirmed the presence of both cell populations in the 50/50 mixed tissues at the time of mechanical characterization. Isometric muscle twitch relaxation times of these mixed-population engineered heart tissues showed agreement with the predictions from the model, namely that the measured relaxation rate of 50/50 mixed tissues more closely resembled that of tissues made with 100% fast-relaxing cells. Our observations suggest that cardiomyocyte diversity can play an important role in determining tissue-level relaxation.


Assuntos
Modelos Cardiovasculares , Relaxamento Muscular , Miócitos Cardíacos/metabolismo , Cinética , Miócitos Cardíacos/citologia , Engenharia Tecidual
8.
J Physiol ; 598(14): 2909-2922, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-30624779

RESUMO

Cardiomyocytes derived from human induced pluripotent stem cells (iPSCs) provide a unique opportunity to understand the pathophysiological effects of genetic cardiomyopathy mutations. In particular, these cells hold the potential to unmask the effects of mutations on contractile behaviour in vitro, providing new insights into genotype-phenotype relationships. With this goal in mind, several groups have established iPSC lines that contain sarcomeric gene mutations linked to cardiomyopathy in patient populations. Their studies have employed diverse systems and methods for performing mechanical measurements of contractility, ranging from single cell techniques to multicellular tissue-like constructs. Here, we review published results to date within the growing field of iPSC-based sarcomeric cardiomyopathy disease models. We devote special attention to the methods of mechanical characterization selected in each case, and how these relate to the paradigms of classical muscle mechanics. An appreciation of these somewhat subtle paradigms can inform efforts to compare the results of different studies and possibly reconcile discrepancies. Although more work remains to be done to improve and possibly standardize methods for producing, maturing, and mechanically interrogating iPSC-derived cardiomyocytes, the initial results indicate that this approach to modelling cardiomyopathies will continue to provide critical insights into these devastating diseases.


Assuntos
Cardiomiopatias , Células-Tronco Pluripotentes Induzidas , Cardiomiopatias/genética , Diferenciação Celular , Humanos , Mutação , Miócitos Cardíacos , Sarcômeros
9.
Am J Physiol Heart Circ Physiol ; 318(6): H1516-H1524, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383992

RESUMO

Engineered heart tissues (EHTs) have emerged as a robust in vitro model to study cardiac physiology. Although biomimetic culture environments have been developed to better approximate in vivo conditions, currently available methods do not permit full recapitulation of the four phases of the cardiac cycle. We have developed a bioreactor which allows EHTs to undergo cyclic loading sequences that mimic in vivo work loops. EHTs cultured under these working conditions exhibited enhanced concentric contractions but similar isometric contractions compared with EHTs cultured isometrically. EHTs that were allowed to shorten cyclically in culture had increased capacity for contractile work when tested acutely. Increased work production was correlated with higher levels of mitochondrial proteins and mitochondrial biogenesis; this effect was eliminated when tissues were cyclically shortened in the presence of a myosin ATPase inhibitor. Leveraging our novel in vitro method to precisely apply mechanical loads in culture, we grew EHTs under two loading regimes prescribing the same work output but with different associated afterloads. These groups showed no difference in mitochondrial protein expression. In loading regimes with the same afterload but different work output, tissues subjected to higher work demand exhibited elevated levels of mitochondrial protein. Our findings suggest that regulation of mitochondrial mass in cultured human EHTs is potently modulated by the mechanical work the tissue is permitted to perform in culture, presumably communicated through ATP demand. Precise application of mechanical loads to engineered heart tissues in culture represents a novel in vitro method for studying physiological and pathological cardiac adaptation.NEW & NOTEWORTHY In this work, we present a novel bioreactor that allows for active length control of engineered heart tissues during extended tissue culture. Specific length transients were designed so that engineered heart tissues generated complete cardiac work loops. Chronic culture with various work loops suggests that mitochondrial mass and biogenesis are directly regulated by work output.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Humanos , Engenharia Tecidual
10.
Anal Bioanal Chem ; 411(1): 193-203, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30357441

RESUMO

Drugs of abuse and new psychoactive substances (NPS) for recreational purposes are in constant evolution, and their consumption constitutes a significant risk to public health and road safety. The development of an analytical methodology to confirm the intake of illicit drugs in biological fluids is required for an effective control of these substances. An ultra-performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS) was developed for simultaneous determination of 10 synthetic cathinones and 10 illicit drugs in oral fluid easily sampled through non-invasive maneuvers. The UPLC-MS/MS method was coupled to an ultrasound-assisted dispersive liquid-liquid microextraction (US-DLLME), which is a miniaturized and inexpensive technique that uses reduced volumes of solvents and samples. The US-DLLME was optimized by using a 213441//18 asymmetric screening design and a Doehlert design. Sample volume, dispersion and extraction solvent volumes, pH, US time, and amount of sodium chloride were evaluated. The US-DLLME-UPLC-MS/MS method was validated according to international guidelines. Limits of quantitation (LOQs) ranged from 0.25 to 5 ng mL-1, and the linear range spanned from LOQ to 500 ng mL-1 with R2 higher than 0.9907, for most of the target drugs. Precision ranged from 1.7 to 14.8 %RSD. Accuracy, i.e., extraction recovery, ranged from 74 to 129%. The proposed method was successfully applied to the analysis of 15 samples from patients on a drug detoxification program.


Assuntos
Drogas Ilícitas/análise , Microextração em Fase Líquida/métodos , Saliva/química , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Padrões de Referência , Cloreto de Sódio/química , Solventes/química , Espectrometria de Massas em Tandem/métodos
11.
Anaesthesia ; 74(3): 340-347, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30666622

RESUMO

Proper placement of the tracheal tube requires confirmation, and the predominant method in addition to clinical signs is the presence of end-tidal carbon dioxide. Such is the importance of confirmation that novel methods may also have a place. We previously demonstrated using ex-vivo swine tissue a unique spectral reflectance characteristic of tracheal tissue that differs from oesophageal tissue. We hypothesised that this characteristic would be present in living swine tissue and human cadavers. Reflectance spectra in the range 500-650 nm were captured using a customised fibreoptic probe, compact spectrometer and white light source from both the trachea and the oesophagus in anesthetised living swine and in human cadavers. A tracheal detection algorithm using ratio comparisons of reflectance was developed. The existence of the unique tracheal characteristic in both in-vivo swine and cadaver models was confirmed (p < 0.0001 for all comparisons between tracheal and oesophageal tissue at all target wavelengths in both species). Furthermore, our proposed tracheal detection algorithm exhibited a 100% positive predictive value in both models. This has potential utility for incorporation into airway management devices.


Assuntos
Esôfago/diagnóstico por imagem , Intubação Intratraqueal/métodos , Traqueia/diagnóstico por imagem , Animais , Cadáver , Feminino , Tecnologia de Fibra Óptica , Humanos , Suínos
14.
Eur J Clin Microbiol Infect Dis ; 36(8): 1511-1517, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28343274

RESUMO

OBJECTIVE: The aims of our study were to determine the factors associated with developing haematological toxicity (HT) in patients taking linezolid (LZD), to develop a predictive model of HT in these patients, and to evaluate factors associated with 30-day mortality. METHODS: This was an observational retrospective cohort study of patients treated for at least 5 days with LDZ in 2015. Demographic, clinical and analytical data were collected. Development of HT was defined as a 25% platelet count decrease between the basal count and the 1-week lab test. RESULTS: Five hundred forty-nine patients were finally included, mean age was 73.3 (SD 15.4) years, and 303 (55.2%) were men. One hundred seventy-five (30.1%) patients achieved HT criteria during treatment with LZD and 41 (7.5%) died. The final model included the presence of cerebrovascular disease (2 points), moderate or severe liver disease (2 points), renal failure (2 points) and basal platelet count less than 90,000/mm3 (8 points). This new model showed an AUC of 0.711 (IC 95% 0.664-0.757; p < 0.001) to predict the development of HT. The probability of HT based on this classification was 6.2, 29.9 and 76.5% for low (0-4 points), intermediate (5-10 points) and high risk (>10 points), respectively. The independent variables associated with 30-day mortality were metastatic solid tumor, lymphoma, age >75 years and HT. CONCLUSION: This score could help in the identification of patients with high risk for HT and assess the use of an antibiotic other than LZD, an important issue considering its relation with 30-day mortality observed in our study.


Assuntos
Antibacterianos/efeitos adversos , Técnicas de Apoio para a Decisão , Linezolida/efeitos adversos , Trombocitopenia/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Feminino , Humanos , Linezolida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Retrospectivos , Medição de Risco
16.
J Appl Toxicol ; 35(4): 418-25, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25091865

RESUMO

Opioids and cocaine are widely used at present, both for recreational purposes and as drugs of abuse. This raises the need to develop new analytical methods specifically designed for the simultaneous detection of several drugs of abuse in biological samples. In this work, dispersive liquid-liquid microextraction (DLLME) was assessed as a new sample treatment for the simultaneous extraction of morphine (MOR), 6-acetylmorphine (6AM), cocaine (COC), benzoylecgonine (BZE) and methadone (MET) from human plasma. Preliminary assays were done before developing an experimental design based on a Uniform Network Doehlert which allowed the optimum extraction conditions to be identified, namely: a volume of extractant solvent (chloroform) and dispersant solvent (acetonitrile) of 220 µl and 3.2 ml, respectively; 0.2 g of NaCl as a salting-out additive; pH 10.6 and ultrasound stirring for 3.5 min. The resulting extracts were analyzed by high-performance liquid chromatography with photodiode array detection (HPLC-PDA), using an XBridge® RP18 column (250 × 4.6 mm i.d., 5 µm particle size). Calibration graphs were linear over the concentration range 0.1-10 µg ml⁻¹, and detection limits ranged from 13.9 to 28.5 ng ml⁻¹. Precision calculated at three different concentration levels in plasma was included in the range 0.1-6.8% RSD. Recoveries of the five drugs were all higher than 84% on average. Finally the proposed method was successfully applied to 22 plasma samples from heroin, cocaine and/or methadone users, and the most frequently detected drug was benzoylecgonine, followed by methadone, cocaine and morphine.


Assuntos
Cocaína/sangue , Drogas Ilícitas/sangue , Metadona/sangue , Morfina/sangue , Tratamento de Substituição de Opiáceos , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/sangue , Métodos Analíticos de Preparação de Amostras , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Cocaína/análogos & derivados , Cocaína/química , Humanos , Concentração de Íons de Hidrogênio , Drogas Ilícitas/química , Limite de Detecção , Microextração em Fase Líquida , Metadona/química , Metadona/uso terapêutico , Morfina/química , Derivados da Morfina/sangue , Derivados da Morfina/química , Fotometria , Reprodutibilidade dos Testes , Solubilidade , Espectrofotometria Ultravioleta , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Ultrassom/métodos
18.
JCI Insight ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39405183

RESUMO

Human periosteal skeletal stem cells (P-SSCs) are critical for cortical bone maintenance and repair. However, their in vivo identity, molecular characteristics, and specific markers remain unknown. Here, single-cell sequencing revealed human periosteum contains SSC clusters expressing known SSC markers, PDPN and PDGFRA. Notably, human P-SSCs, but not bone marrow SSCs (BM-SSCs), selectively expressed newly identified markers, LRP1 and CD13. These LRP1+CD13+ human P-SSCs were perivascular cells with high osteochondrogenic but minimal adipogenic potential. Upon transplantation into bone injuries in mice, they preserved self-renewal capability in vivo. Single-cell analysis of mouse periosteum further supported the preferential expression of LRP1 and CD13 in Prx1+ P-SSCs. When Lrp1 was conditionally deleted in Prx1-lineage cells, it led to severe bone deformity, short statue, and periosteal defects. By contrast, local treatment with a LRP1 agonist at the injury sites induced early P-SSC proliferation and bone healing. Thus, human and mouse periosteum contains unique osteochondrogenic stem cell subsets, and these P-SSCs express specific markers, LRP1 and CD13, with regulatory mechanism through LRP1 that enhances P-SSC function and bone repair.

19.
J Hepatocell Carcinoma ; 11: 1891-1905, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39372712

RESUMO

Purpose: Hepatocellular carcinoma (HCC) related to metabolic dysfunction-associated steatotic liver disease (MASLD) is often diagnosed at a late stage, and its incidence is increasing. Predictive biomarkers are therefore needed to identify individuals at high risk of HCC. We aimed to characterize the gut microbiome and hepatic transcriptome associated with HCC development in female mice with hepatocyte-deletion of Pten (HepPten -). These mice present with large variations in HCC development, making them a powerful model for biomarker discovery. Methods & Results: Sequencing of stool 16S and hepatic RNA was performed on a first set of mice. Among all liver histology parameters measured, the strongest association with microbiome composition changes was with the number of tumors detected at necropsy, followed by inflammation. The gut microbiome of mice with more than 2 tumors was enriched with Lachnospiraceae UCG and depleted of Palleniella intestinalis and Odoribacter. In contrast, hepatic transcriptomic changes were most strongly associated with tumor burden, followed by liver fibrosis. The 840 differentially expressed genes correlating with tumor burden were enriched in leukocyte extravasation and interleukin 10 receptor A (IL10RA) pathways. In addition, the abundance of Spp1-high epithelial cells is correlated with tumor burden. Association between tumor number and depletion of Palleniella intestinalis, and between tumor burden and circulating levels of C-X-C motif chemokine ligand 13 (CXCL13) and stem cell factor (SCF), was further validated in an independent set of mice. Conclusion: We identified microbiome components contributing to liver carcinogenesis by inducing inflammation, and changes in hepatic gene expression and hepatic cells distribution that contribute to tumor growth. Such information can be highly valuable for the development of new prevention strategies as well as of new biomarkers for risk modeling in HCC.

20.
mSystems ; 9(9): e0043424, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39166873

RESUMO

Mexican Americans are disproportionally affected by metabolic dysfunction-associated steatotic liver disease (MASLD), which often co-occurs with diabetes. Despite extensive evidence on the causative role of the gut microbiome in MASLD, studies determining the involvement of the gut phageome are scarce. In this cross-sectional study, we characterized the gut phageome in Mexican Americans of South Texas by stool shotgun metagenomic sequencing of 340 subjects, concurrently screened for liver steatosis by transient elastography. Inter-individual variations in the phageome were associated with gender, country of birth, diabetes, and liver steatosis. The phage signatures for diabetes and liver steatosis were subsequently determined. Enrichment of Inoviridae was associated with both diabetes and liver steatosis. Diabetes was further associated with the enrichment of predominantly temperate Escherichia phages, some of which possessed virulence factors. Liver steatosis was associated with the depletion of Lactococcus phages r1t and BK5-T, and enrichment of the globally prevalent Crassvirales phages, including members of genus cluster IX (Burzaovirus coli, Burzaovirus faecalis) and VI (Kahnovirus oralis). The Lactococcus phages showed strong correlations and co-occurrence with Lactococcus lactis, while the Crassvirales phages, B. coli, B. faecalis, and UAG-readthrough crAss clade correlated and co-occurred with Prevotella copri. In conclusion, we identified the gut phageome signatures for two closely linked metabolic diseases with significant global burden. These phage signatures may have utility in risk modeling and disease prevention in this high-risk population, and identification of potential bacterial targets for phage therapy.IMPORTANCEPhages influence human health and disease by shaping the gut bacterial community. Using stool samples from a high-risk Mexican American population, we provide insights into the gut phageome changes associated with diabetes and liver steatosis, two closely linked metabolic diseases with significant global burden. Common to both diseases was an enrichment of Inoviridae, a group of phages that infect bacterial hosts chronically without lysis, allowing them to significantly influence bacterial growth, virulence, motility, biofilm formation, and horizontal gene transfer. Diabetes was additionally associated with the enrichment of Escherichia coli-infecting phages, some of which contained virulence factors. Liver steatosis was additionally associated with the depletion of Lactococcus lactis-infecting phages, and enrichment of Crassvirales phages, a group of virulent phages with high global prevalence and persistence across generations. These phageome signatures may have utility in risk modeling, as well as identify potential bacterial targets for phage therapy.


Assuntos
Bacteriófagos , Fígado Gorduroso , Microbioma Gastrointestinal , Americanos Mexicanos , Viroma , Humanos , Masculino , Feminino , Microbioma Gastrointestinal/genética , Bacteriófagos/genética , Pessoa de Meia-Idade , Viroma/genética , Fígado Gorduroso/genética , Estudos Transversais , Adulto , Diabetes Mellitus , Fezes/microbiologia , Fezes/virologia , Idoso
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