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1.
N Engl J Med ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38828955

RESUMO

BACKGROUND: Adrenal insufficiency in patients with classic 21-hydroxylase deficiency congenital adrenal hyperplasia (CAH) is treated with glucocorticoid replacement therapy. Control of adrenal-derived androgen excess usually requires supraphysiologic glucocorticoid dosing, which predisposes patients to glucocorticoid-related complications. Crinecerfont, an oral corticotropin-releasing factor type 1 receptor antagonist, lowered androstenedione levels in phase 2 trials involving patients with CAH. METHODS: In this phase 3 trial, we randomly assigned adults with CAH in a 2:1 ratio to receive crinecerfont or placebo for 24 weeks. Glucocorticoid treatment was maintained at a stable level for 4 weeks to evaluate androstenedione values, followed by glucocorticoid dose reduction and optimization over 20 weeks to achieve the lowest glucocorticoid dose that maintained androstenedione control (≤120% of the baseline value or within the reference range). The primary efficacy end point was the percent change in the daily glucocorticoid dose from baseline to week 24 with maintenance of androstenedione control. RESULTS: All 182 patients who underwent randomization (122 to the crinecerfont group and 60 to the placebo group) were included in the 24-week analysis, with imputation of missing values; 176 patients (97%) remained in the trial at week 24. The mean glucocorticoid dose at baseline was 17.6 mg per square meter of body-surface area per day of hydrocortisone equivalents; the mean androstenedione level was elevated at 620 ng per deciliter. At week 24, the change in the glucocorticoid dose (with androstenedione control) was -27.3% in the crinecerfont group and -10.3% in the placebo group (least-squares mean difference, -17.0 percentage points; P<0.001). A physiologic glucocorticoid dose (with androstenedione control) was reported in 63% of the patients in the crinecerfont group and in 18% in the placebo group (P<0.001). At week 4, androstenedione levels decreased with crinecerfont (-299 ng per deciliter) but increased with placebo (45.5 ng per deciliter) (least-squares mean difference, -345 ng per deciliter; P<0.001). Fatigue and headache were the most common adverse events in the two trial groups. CONCLUSIONS: Among patients with CAH, the use of crinecerfont resulted in a greater decrease from baseline in the mean daily glucocorticoid dose, including a reduction to the physiologic range, than placebo following evaluation of adrenal androgen levels. (Funded by Neurocrine Biosciences; CAHtalyst ClinicalTrials.gov number, NCT04490915.).

2.
Artigo em Inglês | MEDLINE | ID: mdl-38860289

RESUMO

The mucociliary transport apparatus is critical for maintaining lung health via the coordinated movement of cilia to clear mucus and particulates. A metachronal wave propagates across the epithelium when cilia on adjacent multiciliated cells beat slightly out of phase along the proximal-distal axis of the airways in alignment with anatomically directed mucociliary clearance. We hypothesized that metachrony optimizes mucociliary transport (MCT) and that disruptions of calcium signaling would abolish metachrony and decrease MCT. We imaged bronchi from human explants and ferret tracheae using micro-Optical Coherence Tomography (µOCT) to evaluate airway surface liquid depth (ASL), periciliary liquid depth (PCL), cilia beat frequency (CBF), MCT, and metachrony in situ. We developed statistical models that included covariates of MCT. Ferret tracheae were treated with BAPTA-AM (chelator of intracellular Ca2+), lanthanum chloride (nonpermeable Ca2+channel competitive antagonist), and repaglinide (inhibitor of calaxin) to test calcium-dependence of metachrony. We demonstrated metachrony contributes to mucociliary transport of human and ferret airways. MCT was augmented in regions of metachrony compared to non-metachronous regions by 48.1%, P=0.0009 or 47.5%, P<0.0020 in humans and ferrets, respectively. PCL and metachrony were independent contributors to MCT rate in humans; ASL, CBF, and metachrony contribute to ferret MCT rates. Metachrony can be disrupted by interference with calcium signaling including intracellular, mechanosensitive channels, and calaxin. Our results support that the presence of metachrony augments MCT in a calcium-dependent mechanism.

3.
Anal Chem ; 95(34): 12701-12709, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37594382

RESUMO

Probing the entirety of any species metabolome is an analytical grand challenge, especially on a cellular scale. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a common spatial metabolomics assay, but this technique has limited molecular coverage for several reasons. To expand the application space of spatial metabolomics, we developed an on-tissue chemical derivatization (OTCD) workflow using 4-APEBA for the confident identification of several dozen elusive phytocompounds. Overall, this new OTCD method enabled the annotation of roughly 280 metabolites, with only a 10% overlap in metabolic coverage when compared to analog negative ion mode MALDI-MSI on serial sections. We demonstrate that 4-APEBA outperforms other derivatization agents by providing: (1) broad specificity toward carbonyls, (2) low background, and (3) introduction of bromine isotopes. Notably, the latter two attributes also facilitate more confidence in our bioinformatics for data processing. The workflow detailed here trailblazes a path toward spatial hormonomics within plant samples, enhancing the detection of carboxylates, aldehydes, and plausibly other carbonyls. As such, several phytohormones, which have various roles within stress responses and cellular communication, can now be spatially profiled, as demonstrated in poplar root and soybean root nodule.


Assuntos
Aldeídos , Bioensaio , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Ácidos Carboxílicos , Comunicação Celular
4.
Hum Resour Health ; 21(1): 72, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667368

RESUMO

BACKGROUND: Health practitioner regulation (HPR) systems are increasingly recognized as playing an important role in supporting health workforce availability, accessibility, quality, and sustainability, while promoting patient safety. This review aimed to identify evidence on the design, delivery and effectiveness of HPR to inform policy decisions. METHODS: We conducted an integrative analysis of literature published between 2010 and 2021. Fourteen databases were systematically searched, with data extracted and synthesized based on a modified Donabedian framework. FINDINGS: This large-scale review synthesized evidence from a range of academic (n = 410) and grey literature (n = 426) relevant to HPR. We identified key themes and findings for a series of HPR topics organized according to our structures-processes-outcomes conceptual framework. Governance reforms in HPR are shifting towards multi-profession regulators, enhanced accountability, and risk-based approaches; however, comparisons between HPR models were complicated by a lack of a standardized HPR typology. HPR can support government workforce strategies, despite persisting challenges in cross-border recognition of qualifications and portability of registration. Scope of practice reform adapted to modern health systems can improve access and quality. Alternatives to statutory registration for lower-risk health occupations can improve services and protect the public, while standardized evaluation frameworks can aid regulatory strengthening. Knowledge gaps remain around the outcomes and effectiveness of HPR processes, including continuing professional development models, national licensing examinations, accreditation of health practitioner education programs, mandatory reporting obligations, remediation programs, and statutory registration of traditional and complementary medicine practitioners. CONCLUSION: We identified key themes, issues, and evidence gaps valuable for governments, regulators, and health system leaders. We also identified evidence base limitations that warrant caution when interpreting and generalizing the results across jurisdictions and professions. Themes and findings reflect interests and concerns in high-income Anglophone countries where most literature originated. Most studies were descriptive, resulting in a low certainty of evidence. To inform regulatory design and reform, research funders and governments should prioritize evidence on regulatory outcomes, including innovative approaches we identified in our review. Additionally, a systematic approach is needed to track and evaluate the impact of regulatory interventions and innovations on achieving health workforce and health systems goals.


Assuntos
Programas Governamentais , Governo , Humanos , Acreditação , Bases de Dados Factuais , Educação em Saúde
5.
Eur Respir J ; 60(1)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34916262

RESUMO

RATIONALE: The majority of chronic obstructive pulmonary disease (COPD) patients have chronic bronchitis, for which specific therapies are unavailable. Acquired cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction is observed in chronic bronchitis, but has not been proven in a controlled animal model with airway disease. Furthermore, the potential of CFTR as a therapeutic target has not been tested in vivo, given limitations to rodent models of COPD. Ferrets exhibit cystic fibrosis-related lung pathology when CFTR is absent and COPD with bronchitis following cigarette smoke exposure. OBJECTIVES: To evaluate CFTR dysfunction induced by smoking and test its pharmacological reversal by a novel CFTR potentiator, GLPG2196, in a ferret model of COPD with chronic bronchitis. METHODS: Ferrets were exposed for 6 months to cigarette smoke to induce COPD and chronic bronchitis and then treated with enteral GLPG2196 once daily for 1 month. Electrophysiological measurements of ion transport and CFTR function, assessment of mucociliary function by one-micron optical coherence tomography imaging and particle-tracking microrheology, microcomputed tomography imaging, histopathological analysis and quantification of CFTR protein and mRNA expression were used to evaluate mechanistic and pathophysiological changes. MEASUREMENTS AND MAIN RESULTS: Following cigarette smoke exposure, ferrets exhibited CFTR dysfunction, increased mucus viscosity, delayed mucociliary clearance, airway wall thickening and airway epithelial hypertrophy. In COPD ferrets, GLPG2196 treatment reversed CFTR dysfunction, increased mucus transport by decreasing mucus viscosity, and reduced bronchial wall thickening and airway epithelial hypertrophy. CONCLUSIONS: The pharmacologic reversal of acquired CFTR dysfunction is beneficial against pathological features of chronic bronchitis in a COPD ferret model.


Assuntos
Bronquite Crônica , Doença Pulmonar Obstrutiva Crônica , Animais , Bronquite Crônica/tratamento farmacológico , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Furões/metabolismo , Hipertrofia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Microtomografia por Raio-X
6.
Clin Exp Ophthalmol ; 50(1): 50-61, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34714583

RESUMO

BACKGROUND: Prognostic cytological and molecular features of uveal melanoma have been well researched and are essential in management. Samples can be obtained in vivo through fine needle aspirate biopsy, vitrector cutter, forceps or post-enucleation for off-site testing. This study aims to examine cytological and chromosome microarray yields of these samples. METHODS: A retrospective cohort analysis of 119 uveal melanoma biopsies submitted to our laboratory. Samples included those taken in vivo (n = 57) and post-enucleation (n = 62). Patient and tumour features were collected including age, sex, primary tumour location, basal diameter and tumour height. Prognostic outcomes measured include cell morphology, chromosomal status and immunohistochemistry. RESULTS: Post-enucleation biopsies accounted for just over half of our samples (52%). Post-enucleation samples had a more successful genetic yield than in vivo biopsies (77% vs. 50%, p = 0.04) though there was no difference for cytological yields. There was no difference in cytological or microarray yields between instruments. The vitrector biopsy group had the smallest tumour thickness (5 mm vs. 10 mm [fine-needle aspirate biopsy], p = 0.003). There was a strong correlation between monosomy 3, BAP1 aberrancy and epithelioid cell type in post-enucleation samples (Tb  = 0.742, p = 0.005). However, epithelioid morphology was not associated with either monosomy 3 (p = 0.07) or BAP1 aberrancy (p = 0.24) for in vivo biopsies. CONCLUSIONS: All three biopsy instruments provide similar cytological yields as post-enucleation sampling, although post-enucleation samples had a more successful chromosome microarray yield. Epithelioid cytomorphology alone is insufficient for prognostication in in vivo biopsies, immunohistochemistry would be a useful surrogate test.


Assuntos
Neoplasias Uveais , Biópsia por Agulha Fina , Humanos , Melanoma , Monossomia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo
7.
J Chem Inf Model ; 61(1): 481-492, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33404240

RESUMO

The α2a adrenoceptor is a medically relevant subtype of the G protein-coupled receptor family. Unfortunately, high-throughput techniques aimed at producing novel drug leads for this receptor have been largely unsuccessful because of the complex pharmacology of adrenergic receptors. As such, cutting-edge in silico ligand- and structure-based assessment and de novo deep learning methods are well positioned to provide new insights into protein-ligand interactions and potential active compounds. In this work, we (i) collect a dataset of α2a adrenoceptor agonists and provide it as a resource for the drug design community; (ii) use the dataset as a basis to generate candidate-active structures via deep learning; and (iii) apply computational ligand- and structure-based analysis techniques to gain new insights into α2a adrenoceptor agonists and assess the quality of the computer-generated compounds. We further describe how such assessment techniques can be applied to putative chemical probes with a case study involving proposed medetomidine-based probes.


Assuntos
Aprendizado Profundo , Receptores Adrenérgicos alfa 2 , Ligantes , Medetomidina
8.
Hum Resour Health ; 19(1): 1, 2021 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-33388068

RESUMO

BACKGROUND: Health workforce governance has been proposed as key to improving health services delivery, yet few studies have examined the conceptualisation of health workforce governance in detail and exploration in literature remains limited. METHODS: A literature review using PubMed, Google Scholar and grey literature search was conducted to map out the current conceptualisation of health workforce governance. We identified all published literature relating to governance in health workforce since 2000 and analysed them on two fronts: the broad definition of governance, and the operationalisation of broad definition into key dimensions of governance. RESULTS: Existing literature adopts governance concepts established in health literature and does not adapt understanding to the health workforce context. Definitions are largely quoted from health literature whilst dimensions are focused around the sub-functions of governance which emphasise operationalising governance practices over further conceptualisation. Two sub-functions are identified as essential to the governance process: stakeholder participation and strategic direction. CONCLUSIONS: Although governance in health systems has gained increasing attention, governance in health workforce remains poorly conceptualised in literature. We propose an improved conceptualisation in the form of a stakeholder-driven network governance model with the national government as a strong steward against vested stakeholder interests. Further research is needed to explore and develop on the conceptual thinking behind health workforce governance.


Assuntos
Atenção à Saúde , Mão de Obra em Saúde , Programas Governamentais , Humanos , Participação dos Interessados
9.
Health Promot Int ; 36(Supplement_1): i4-i12, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34897442

RESUMO

Governance is an important factor in urban health, and law is an important element of healthy governance. Law can be an intervention local government wields to influence behavior and shape environments. Law can also be an important target of health promotion efforts: Law and the enforcement and implementation behaviors it fosters can promote unhealthy behaviors and environmental conditions, and can act as a barrier to healthy interventions or practices. Finally, law is a design and construction tool for the organization of governance. Law is the means through which cities are formally established. Their powers and duties, organizational structure, boundaries and decision-making procedures are all set by law. Regardless of the form of government, cities have legal levers they can manipulate for health promotion. Cities can use tax authority to influence the price of unhealthy products, or to encourage consumption of healthy foods. Cities can use their legal powers to address incidental legal effects of policies that they themselves cannot control. Cities may also have the authority to use law to address deeper determinants of health. The overall level of income or wealth inequality in a country reflects factors well-beyond a local government's control, but city government nonetheless has levers to directly and indirectly reduce economic and social inequality and their effects. A renewed focus on law and urban governance is the key to assuring health and well-being and closing the health equity gap.


Assuntos
Equidade em Saúde , Governo Local , Cidades , Promoção da Saúde , Humanos , Saúde da População Urbana
10.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466477

RESUMO

Continued expansion of the chemical biology toolbox presents many new and diverse opportunities to interrogate the fundamental molecular mechanisms driving complex plant-microbe interactions. This review will examine metabolic labeling with click chemistry reagents and activity-based probes for investigating the impacts of plant-associated microbes on plant growth, metabolism, and immune responses. While the majority of the studies reviewed here used chemical biology approaches to examine the effects of pathogens on plants, chemical biology will also be invaluable in future efforts to investigate mutualistic associations between beneficial microbes and their plant hosts.


Assuntos
Interações Hospedeiro-Patógeno , Microbiota , Fenômenos Fisiológicos Vegetais , Plantas/metabolismo , Plantas/microbiologia , Química Click
11.
Am J Physiol Lung Cell Mol Physiol ; 318(6): L1165-L1171, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32292070

RESUMO

Bronchopulmonary dysplasia (BPD), a long-term respiratory morbidity of prematurity, is characterized by attenuated alveolar and vascular development. Supplemental oxygen and immature antioxidant defenses contribute to BPD development. Our group identified thioredoxin reductase-1 (TXNRD1) as a therapeutic target to prevent BPD. The present studies evaluated the impact of the TXNRD1 inhibitor aurothioglucose (ATG) on pulmonary responses and gene expression in newborn C57BL/6 pups treated with saline or ATG (25 mg/kg ip) within 12 h of birth and exposed to room air (21% O2) or hyperoxia (>95% O2) for 72 h. Purified RNA from lung tissues was sequenced, and differential expression was evaluated. Hyperoxic exposure altered ~2,000 genes, including pathways involved in glutathione metabolism, intrinsic apoptosis signaling, and cell cycle regulation. The isolated effect of ATG treatment was limited primarily to genes that regulate angiogenesis and vascularization. In separate studies, pups were treated as described above and returned to room air until 14 days. Vascular density analyses were performed, and ANOVA indicated an independent effect of hyperoxia on vascular density and alveolar architecture at 14 days. Consistent with RNA-seq analyses, ATG significantly increased vascular density in room air, but not in hyperoxia-exposed pups. These findings provide insights into the mechanisms by which TXNRD1 inhibitors may enhance lung development.


Assuntos
Ar , Aurotioglucose/farmacologia , Hiperóxia/patologia , Pulmão/irrigação sanguínea , Pulmão/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Doença Aguda , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/genética , DNA/biossíntese , Glutationa/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/embriologia , Camundongos Endogâmicos C57BL , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/embriologia , Alvéolos Pulmonares/patologia , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Transcriptoma/genética , Regulação para Cima/efeitos dos fármacos
13.
Eur Respir J ; 55(1)2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672759

RESUMO

The mechanisms by which cigarette smoking impairs airway mucus clearance are not well understood. We recently established a ferret model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD) exhibiting chronic bronchitis. We investigated the effects of cigarette smoke on mucociliary transport (MCT).Adult ferrets were exposed to cigarette smoke for 6 months, with in vivo mucociliary clearance measured by technetium-labelled DTPA retention. Excised tracheae were imaged with micro-optical coherence tomography. Mucus changes in primary human airway epithelial cells and ex vivo ferret airways were assessed by histology and particle tracking microrheology. Linear mixed models for repeated measures identified key determinants of MCT.Compared to air controls, cigarette smoke-exposed ferrets exhibited mucus hypersecretion, delayed mucociliary clearance (-89.0%, p<0.01) and impaired tracheal MCT (-29.4%, p<0.05). Cholinergic stimulus augmented airway surface liquid (ASL) depth (5.8±0.3 to 7.3±0.6 µm, p<0.0001) and restored MCT (6.8±0.8 to 12.9±1.2 mm·min-1, p<0.0001). Mixed model analysis controlling for covariates indicated smoking exposure, mucus hydration (ASL) and ciliary beat frequency were important predictors of MCT. Ferret mucus was hyperviscous following smoke exposure in vivo or in vitro, and contributed to diminished MCT. Primary cells from smokers with and without COPD recapitulated these findings, which persisted despite the absence of continued smoke exposure.Cigarette smoke impairs MCT by inducing airway dehydration and increased mucus viscosity, and can be partially abrogated by cholinergic secretion of fluid secretion. These data elucidate the detrimental effects of cigarette smoke exposure on mucus clearance and suggest additional avenues for therapeutic intervention.


Assuntos
Desidratação , Doença Pulmonar Obstrutiva Crônica , Adulto , Humanos , Depuração Mucociliar , Muco , Fumar/efeitos adversos , Viscosidade
14.
Invest New Drugs ; 38(5): 1421-1429, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31984451

RESUMO

Background Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with very limited treatment options. Nevanimibe HCl (formerly ATR-101), a novel adrenal-specific sterol O-acyltransferase 1 (SOAT1) inhibitor, has been shown in nonclinical studies to decrease adrenal steroidogenesis at lower doses and to cause apoptosis of adrenocortical cells at higher doses. Methods This phase 1, multicenter, open-label study assessed the safety and pharmacokinetics (PK) of nevanimibe in adults with metastatic ACC (NCT01898715). A "3 + 3" dose-escalation design was used. Adverse events (AEs), PK, and tumor response based on Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 were evaluated every 2 months. Results 63 patients with metastatic ACC, all of whom had previously failed systemic chemotherapy and only 2 of whom were mitotane-naïve, were dosed with oral nevanimibe at doses ranging from 1.6 mg/kg/day to 158.5 mg/kg/day. Subjects who did not experience tumor progression or a dose-limiting toxicity (DLT) could continue to receive additional cycles. No patients experienced a complete or partial response; however, 13 of the 48 (27%) patients who underwent imaging at 2 months had stable disease (SD), and 4 of these had SD > 4 months. In addition, drug-related adrenal insufficiency, considered a pharmacologic effect of nevanimibe, was observed in two patients. The most common treatment-emergent AEs were gastrointestinal disorders (76%), including diarrhea (44%) and vomiting (35%). A maximum tolerated dose (MTD) could not be defined, as very few dose-limiting toxicities (DLTs) occurred. Because the large number of tablets required at the highest dose (i.e., ~24 tablets/day) resulted in low-grade gastrointestinal adverse effects, a maximum feasible dose of 128.2 mg/kg/day was established as a dose that could be taken on a long-term basis. Conclusions This study demonstrated the safety of nevanimibe at doses of up to ~6000 mg BID. As the total number of tablets required to achieve an MTD exceeded practical administration limits, a maximum feasible dose was defined. Given that the expected exposure levels necessary for an apoptotic effect could not be achieved, the current formulation of nevanimibe had limited efficacy in patients with advanced ACC.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Carcinoma Adrenocortical/tratamento farmacológico , Esterol O-Aciltransferase/antagonistas & inibidores , Ureia/análogos & derivados , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Comprimidos , Ureia/administração & dosagem , Ureia/efeitos adversos , Ureia/sangue , Ureia/farmacocinética
15.
Chem Res Toxicol ; 33(2): 414-425, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-31872761

RESUMO

Acute and chronic exposures to organophosphates (OPs), including agricultural pesticides, industrial chemicals, and chemical warfare agents, remain a significant worldwide health risk. The mechanisms by which OPs alter development and cognition in exposed individuals remain poorly understood, in part due to the large number of structurally diverse OPs and the wide range of affected proteins and signaling pathways. To investigate the influence of structure on OP targets in mammalian systems, we have developed a series of probes for activity-based protein profiling (ABPP) featuring two distinct reactive groups that mimic OP chemical reactivity. FOP features a fluorophosphonate moiety, and PODA and CODA utilize a dialkynyl phosphate ester; both reactive group types target serine hydrolase activity. As the oxon represents the highly reactive and toxic functional group of many OPs, the new probes described herein enhance our understanding of tissue-specific reactivity of OPs. Chemoproteomic analysis of mouse tissues treated with the probes revealed divergent protein profiles, demonstrating the influence of probe structure on protein targeting. These targets also vary in sensitivity toward different OPs. The simultaneous use of multiple probes in ABPP experiments may therefore offer more comprehensive coverage of OP targets; FOP consistently labeled more targets in both brain and liver than PODA or CODA, suggesting the dialkyne warhead is more selective for enzymes in major signaling pathways than the more reactive fluorophosphonate warhead. Additionally, the probes can be used to assess reactivation of OP-inhibited enzymes by N-oximes and may serve as diagnostic tools for screening of therapeutic candidates in a panel of protein targets. These applications will help clarify the short- and long-term effects of OP toxicity beyond acetylcholinesterase inhibition, investigate potential points of convergence for broad spectrum therapeutic development, and support future efforts to screen candidate molecules for efficacy in various model systems.


Assuntos
Encéfalo/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Fígado/efeitos dos fármacos , Organofosfatos/farmacologia , Acetilcolinesterase/metabolismo , Animais , Encéfalo/metabolismo , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Fígado/metabolismo , Camundongos , Estrutura Molecular , Organofosfatos/química
16.
Am J Respir Cell Mol Biol ; 61(2): 162-173, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30576219

RESUMO

Cigarette smoking is associated with chronic obstructive pulmonary disease and chronic bronchitis. Acquired ion transport abnormalities, including cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction, caused by cigarette smoking have been proposed as potential mechanisms for mucus obstruction in chronic bronchitis. Although e-cigarette use is popular and perceived to be safe, whether it harms the airways via mechanisms altering ion transport remains unclear. In the present study, we sought to determine if e-cigarette vapor, like cigarette smoke, has the potential to induce acquired CFTR dysfunction, and to what degree. Electrophysiological methods demonstrated reduced chloride transport caused by vaporized e-cigarette liquid or vegetable glycerin at various exposures (30 min, 57.2% and 14.4% respectively, vs. control; P < 0.0001), but not by unvaporized liquid (60 min, 17.6% vs. untreated), indicating that thermal degradation of these products is required to induce the observed defects. We also observed reduced ATP-dependent responses (-10.8 ± 3.0 vs. -18.8 ± 5.1 µA/cm2 control) and epithelial sodium channel activity (95.8% reduction) in primary human bronchial epithelial cells after 5 minutes, suggesting that exposures dramatically inhibit epithelial ion transport beyond CFTR, even without diminished transepithelial resistance or cytotoxicity. Vaporizing e-cigarette liquid produced reactive aldehydes, including acrolein (shown to induce acquired CFTR dysfunction), as quantified by mass spectrometry, demonstrating that respiratory toxicants in cigarette smoke can also be found in e-cigarette vapor (30 min air, 224.5 ± 15.99; unvaporized liquid, 284.8 ± 35.03; vapor, 54,468 ± 3,908 ng/ml; P < 0.0001). E-cigarettes can induce ion channel dysfunction in airway epithelial cells, partly through acrolein production. These findings indicate a heretofore unknown toxicity of e-cigarette use known to be associated with chronic bronchitis onset and progression, as well as with chronic obstructive pulmonary disease severity.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Células Epiteliais/efeitos dos fármacos , Glicerol/efeitos adversos , Transporte de Íons , Fumaça/efeitos adversos , Fumar/efeitos adversos , Acroleína/química , Trifosfato de Adenosina/metabolismo , Brônquios/metabolismo , Bronquite Crônica/fisiopatologia , Sobrevivência Celular , Fumar Cigarros , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Progressão da Doença , Eletrofisiologia , Células Epiteliais/metabolismo , Glicerol/metabolismo , Humanos , Espectrometria de Massas , Muco/metabolismo , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sistema Respiratório/efeitos dos fármacos , Fatores de Tempo
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