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1.
Proc Natl Acad Sci U S A ; 121(5): e2311487121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38261611

RESUMO

Roughly one-half of mice with partial defects in two immune tolerance pathways (AireGW/+Lyn-/- mice) spontaneously develop severe damage to their retinas due to T cell reactivity to Aire-regulated interphotoreceptor retinoid-binding protein (IRBP). Single-cell T cell receptor (TCR) sequencing of CD4+ T cells specific for a predominate epitope of IRBP showed a remarkable diversity of autoantigen-specific TCRs with greater clonal expansions in mice with disease. TCR transgenic mice made with an expanded IRBP-specific TCR (P2.U2) of intermediate affinity exhibited strong but incomplete negative selection of thymocytes. This negative selection was absent in IRBP-/- mice and greatly defective in AireGW/+ mice. Most P2.U2+/- mice and all P2.U.2+/-AireGW/+ mice rapidly developed inflammation of the retina and adjacent uvea (uveitis). Aire-dependent IRBP expression in the thymus also promoted Treg differentiation, but the niche for this fate determination was small, suggesting differences in antigen presentation leading to negative selection vs. thymic Treg differentiation and a stronger role for negative selection in preventing autoimmune disease in the retina.


Assuntos
Apresentação de Antígeno , Receptores de Antígenos de Linfócitos T , Animais , Camundongos , Autoantígenos , Modelos Animais de Doenças , Camundongos Endogâmicos , Camundongos Transgênicos
3.
Nature ; 550(7675): 255-259, 2017 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-28953886

RESUMO

Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand. Recent studies have identified brain areas outside the hypothalamus that are activated under these 'non-homeostatic' conditions, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptor for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the 'emergency circuit' that shapes feeding responses to stressful conditions. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.


Assuntos
Peso Corporal/fisiologia , Tronco Encefálico/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator 15 de Diferenciação de Crescimento/metabolismo , Animais , Tronco Encefálico/citologia , Tronco Encefálico/efeitos dos fármacos , Núcleo Central da Amígdala/citologia , Núcleo Central da Amígdala/fisiologia , Ingestão de Alimentos/fisiologia , Metabolismo Energético/fisiologia , Comportamento Alimentar , Feminino , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/deficiência , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator 15 de Diferenciação de Crescimento/genética , Fator 15 de Diferenciação de Crescimento/farmacologia , Homeostase , Masculino , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleos Parabraquiais/citologia , Núcleos Parabraquiais/fisiologia , Estresse Psicológico
4.
J Clin Microbiol ; 56(8)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29848567

RESUMO

The current methods available to diagnose antimicrobial-resistant Mycobacterium tuberculosis infections require a positive culture or only test a limited number of resistance-associated mutations. A rapid accurate identification of antimicrobial resistance enables the prompt initiation of effective treatment. Here, we determine the utility of whole-genome sequencing (WGS) of M. tuberculosis directly from routinely obtained diagnostic sputum samples to provide a comprehensive resistance profile compared to that from mycobacterial growth indicator tube (MGIT) WGS. We sequenced M. tuberculosis from 43 sputum samples by targeted DNA enrichment using the Agilent SureSelectXT kit, and 43 MGIT positive samples from each participant. Thirty two (74%) sputum samples and 43 (100%) MGIT samples generated whole genomes. The times to antimicrobial resistance profiles and concordance were compared with Xpert MTB/RIF and phenotypic resistance testing from cultures of the same samples. Antibiotic susceptibility could be predicted from WGS of sputum within 5 days of sample receipt and up to 24 days earlier than WGS from MGIT culture and up to 31 days earlier than phenotypic testing. Direct sputum results could be reduced to 3 days with faster hybridization and if only regions encoding drug resistance are sequenced. We show that direct sputum sequencing has the potential to provide comprehensive resistance detection significantly faster than MGIT whole-genome sequencing or phenotypic testing of resistance from cultures in a clinical setting. This improved turnaround time enables prompt appropriate treatment with associated patient and health service benefits. Improvements in sample preparation are necessary to ensure comparable sensitivities and complete resistance profile predictions in all cases.


Assuntos
Farmacorresistência Bacteriana/genética , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose/diagnóstico , Sequenciamento Completo do Genoma , Antituberculosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Diagnóstico Precoce , Genoma Bacteriano/genética , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Diagnóstico Molecular/normas , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Escarro/química , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
5.
J Pharmacol Exp Ther ; 365(2): 281-290, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29472517

RESUMO

To determine the effects of nordihydroguaiaretic acid (NDGA) on metabolic and molecular changes in response to feeding a typical American fast food or Western diet, mice were fed an American lifestyle-induced obesity syndrome (ALIOS) diet and subjected to metabolic analysis. Male C57BL/6J mice were randomly assigned to the ALIOS diet, the ALIOS diet supplemented with NDGA (NDGA+ALIOS), or a control diet and were maintained on the specific diet for 8 weeks. Mice fed the ALIOS diet showed increased body, liver, and epididymal fat pad weight as well as increased plasma alanine transaminase (ALT) and aspartate aminotransferase (AST) levels (a measure of liver injury) and liver triglyceride content. Coadministration of NDGA normalized body and epididymal fat pad weight, ALT and AST levels, and liver triglycerides. NDGA treatment also improved insulin sensitivity but not glucose intolerance in mice fed the ALIOS diet. In mice fed the NDGA+ALIOS diet, NDGA supplementation induced peroxisome proliferator-activated receptor α (PPARα; the master regulator of fatty acid oxidation) and mRNA levels of carnitine palmitoyltransferases Cpt1c and Cpt2, key genes involved in fatty acid oxidation, compared with the ALIOS diet. NDGA significantly reduced liver endoplasmic reticulum (ER) stress response C/EBP homologous protein, compared with chow or the ALIOS diet, and also ameliorated ALIOS diet-induced elevation of apoptosis signaling protein, caspase 3. Likewise, NDGA downregulated the ALIOS diet-induced mRNA levels of Pparg, fatty acid synthase Fasn, and diacylglycerol acyltransferase Dgat2 NDGA treatment of ALIOS-fed mice upregulated the hepatic expression of antioxidant enzymes, glutathione peroxidase 4, and peroxiredoxin 3 proteins. In conclusion, we provide evidence that NDGA improves metabolic dysregulation by simultaneously modulating the PPARα transcription factor and key genes involved in fatty acid oxidation, key antioxidant and lipogenic enzymes, and apoptosis and ER stress signaling pathways.


Assuntos
Dieta Ocidental/efeitos adversos , Larrea/química , Estilo de Vida , Masoprocol/farmacologia , Obesidade/metabolismo , Obesidade/prevenção & controle , Adipogenia/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos/metabolismo , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/induzido quimicamente , Obesidade/patologia , Oxirredução/efeitos dos fármacos , PPAR alfa/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
6.
Int Arch Allergy Immunol ; 173(4): 213-224, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850947

RESUMO

BACKGROUND: Allergic rhinitis (AR) is a worldwide health problem with rising prevalence. To enhance the estimation of AR prevalence in epidemiological studies, the Score for AR (SFAR), a screening tool, has been developed and widely used. An 8-item SFAR is a handy, self-administered instrument assessing the information on nasal and eye symptoms, seasonal increase in symptoms, skin test results, and previous AR diagnoses. This study aimed to adapt the SFAR to the Chinese population (CSFAR) and validate it by testing its psychometric properties and diagnostic accuracy. METHODS: This methodological study involved translation and validation phases. Different batches of participants were recruited for the above purposes. RESULTS: In phase 1, the CSFAR obtained satisfactory item (80-100%) and scale level (97.8%) semantic equivalence, content validity index (96.7%), comprehensibility (100%), cross-language testing (κ = 0.44-0.83 for item-to-item agreement; intraclass correlation coefficient [ICC] = 0.95, p < 0.05-0.001). In phase 2, CSFAR showed satisfactory internal consistency (α = 0.83), 1-month (ICC = 0.88) and 1-year stability (ICC = 0.85), and construct validity (significant correlation between CSFAR and impairments induced by AR: r = 0.47, p < 0.001). Based on the receiver-operating characteristic curve, comparing the CSFAR with diagnosis made by specialists, an optimal cutoff value was 6 (sensitivity 81.8% and specificity 80.3%). CONCLUSION: SFAR was translated into a Chinese version, the CSFAR. Satisfactory results were obtained for its equivalence, appropriateness, comprehensibility, and relevance, as well as its reliability and validity. A cutoff value of 6 was recommended to increase the diagnostic accuracy in environments with less pollen. This study provides evidence that the SFAR we adapted for the Chinese population is a valuable tool in AR screening.


Assuntos
Rinite Alérgica/diagnóstico , Rinite Alérgica/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/psicologia , Humanos , Pessoa de Meia-Idade , Psicometria , Adulto Jovem
7.
Exp Brain Res ; 233(7): 2205-14, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25939533

RESUMO

Abuse of cough mixture is increasingly prevalent worldwide. Clinical studies showed that chronic consumption of cough mixture at high dosages may lead to psychiatric symptoms, especially affective disturbances, with the underlying mechanisms remain elusive. The present study aims at exploring the effect of repeated, high-dose dextromethorphan (DXM, a common active component of cough mixture) treatment on adult hippocampal neurogenesis, which is associated with pathophysiology of mood disturbances. After treatment with a high-dose of DXM (40 mg/kg/day) for 2 weeks, Sprague-Dawley rats showed increased depression-like behavior when compared to the control animals. Neurogenesis in the hippocampus was suppressed by DXM treatment, which was indicated by decreases in number of proliferative cells and doublecortin (an immature neuron marker)-positive new neurons. Furthermore, the dendritic complexity of the immature neurons was suppressed by DXM treatment. These findings suggest that DXM induces depression- and anxiety-like behavior and suppresses neurogenesis in rats. The current experimental paradigm may serve as an animal model for study on affective effect of cough mixture abuse, rehabilitation treatment options for abusers and the related neurological mechanisms.


Assuntos
Depressão/induzido quimicamente , Depressão/patologia , Dextrometorfano/toxicidade , Antagonistas de Aminoácidos Excitatórios/toxicidade , Hipocampo/patologia , Neurogênese/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Proliferação de Células/efeitos dos fármacos , Dendritos/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Comportamento Exploratório/efeitos dos fármacos , Relações Interpessoais , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neuropeptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Natação/psicologia , Fatores de Tempo
8.
Anim Genet ; 45(6): 888-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25178154

RESUMO

Stock enhancement, restocking and sea ranching are being increasingly applied in both fisheries and conservation. The contribution of hatchery stock to fishery harvest and the maintenance of the genetic structure of stocked populations are both important considerations when releasing captive-bred organisms into natural systems. Use of wild-caught broodstock generally overcomes some of the genetic problems associated with domesticated hatchery populations, but there is still a need to ensure that a sufficient proportion of the natural population contribute to production of the stocked cohort to realise the genetic benefits of using wild-caught broodstock. Releases of Penaeus (Melicertus) plebejus are under investigation as a means of increasing prawn production in recruitment-limited areas. We used the highly variable mitochondrial control region (mtCR) to assign post-larvae to maternal lineages in the hatchery and also to investigate the reproductive performance of female broodstock in terms of contribution to the production of the cohorts of post-larvae in the hatchery. Our data showed that mtCR can be a useful tool for tracking lineages and provided genetic evidence that unequal contribution and underproducing females can occur even in wild-caught broodstock. This work therefore highlights the importance of monitoring the genetic composition of pre-release hatchery stocks.


Assuntos
DNA Mitocondrial/genética , Genética Populacional , Penaeidae/genética , Animais , Animais Selvagens/genética , Aquicultura , Cruzamento , Conservação dos Recursos Naturais , Feminino , Pesqueiros , Marcadores Genéticos , Haplótipos , Dados de Sequência Molecular
9.
Int J Food Sci Nutr ; 65(7): 868-73, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24945597

RESUMO

Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H(2)O(2))-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3-10 µM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H(2)O(2) on H9c2 cells. It could also protect H9c2 cells against H(2)O(2)-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H(2)O(2) or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/toxicidade , Mioblastos Cardíacos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ácidos Sulfínicos/farmacologia , Animais , Compostos de Bifenilo , Linhagem Celular , Dissulfetos , Oxidantes/toxicidade , Estresse Oxidativo , Picratos , Ratos
10.
Surg Pathol Clin ; 17(2): 173-192, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692803

RESUMO

Granulomas are frequently encountered by pathologists in all types of lung specimens and arise from diverse etiologies. They should always be reported as necrotizing or non-necrotizing, with microorganism stains performed to evaluate for infection. With attention to distribution, quality (poorly vs well-formed), associated features, and correlation with clinical, radiologic, and laboratory data, the differential diagnosis for granulomatous lung disease can usually be narrowed to a clinically helpful "short list." This review describes a practical approach to pulmonary granulomas and reviews the clinicopathological aspects of common entities, including infectious (mycobacteria, fungi) and noninfectious (hypersensitivity pneumonitis, sarcoid, and vasculitis) causes.


Assuntos
Pneumopatias , Humanos , Diagnóstico Diferencial , Pneumopatias/patologia , Pneumopatias/diagnóstico , Granuloma do Sistema Respiratório/patologia , Granuloma do Sistema Respiratório/diagnóstico , Granuloma/patologia , Granuloma/diagnóstico , Pulmão/patologia , Alveolite Alérgica Extrínseca/diagnóstico , Alveolite Alérgica Extrínseca/patologia , Sarcoidose Pulmonar/patologia , Sarcoidose Pulmonar/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/patologia
11.
Am J Respir Cell Mol Biol ; 48(1): 114-24, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23065132

RESUMO

Vehicle exhaust is rich in polycyclic aromatic hydrocarbons (PAHs) and is a dominant contributor to urban particulate pollution (PM). Exposure to PM is linked to respiratory and cardiovascular morbidity and mortality in susceptible populations, such as children. PM can contribute to the development and exacerbation of asthma, and this is thought to occur because of the presence of electrophiles in PM or through electrophile generation via the metabolism of PAHs. Glutathione (GSH), an abundant intracellular antioxidant, confers cytoprotection through conjugation of electrophiles and reduction of reactive oxygen species. GSH-dependent phase II detoxifying enzymes glutathione peroxidase and glutathione S-transferase facilitate metabolism and conjugation, respectively. Ambient particulates are highly variable in composition, which complicates systematic study. In response, we have developed a replicable ultrafine premixed flame particle (PFP)-generating system for in vivo studies. To determine particle effects in the developing lung, 7-day-old neonatal and adult rats inhaled 22 µg/m(3) PFP during a single 6-hour exposure. Pulmonary GSH and related phase II detoxifying gene and protein expression were evaluated 2, 24, and 48 hours after exposure. Neonates exhibited significant depletion of GSH despite higher initial baseline levels of GSH. Furthermore, we observed attenuated induction of phase II enzymes (glutamate cysteine ligase, glutathione reductase, glutathione S-transferase, and glutathione peroxidase) in neonates compared with adult rats. We conclude that developing neonates have a limited ability to deviate from their normal developmental pattern that precludes adequate adaptation to environmental pollutants, which results in enhanced cytotoxicity from inhaled PM.


Assuntos
Antioxidantes/metabolismo , Glutationa/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Material Particulado/toxicidade , Administração por Inalação , Fatores Etários , Animais , Animais Recém-Nascidos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Pulmão/crescimento & desenvolvimento , Masculino , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Emissões de Veículos/toxicidade , Glutationa Peroxidase GPX1
12.
Am J Physiol Lung Cell Mol Physiol ; 304(10): L665-77, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23502512

RESUMO

Vehicle exhaust is rich in polycyclic aromatic hydrocarbons (PAH) and can be a dominant contributor to ultrafine urban particulate matter (PM). Exposure to ultrafine PM is correlated with respiratory infections and asthmatic symptoms in young children. The lung undergoes substantial growth, alveolarization, and cellular maturation within the first years of life, which may be impacted by environmental pollutants such as PM. PAHs in PM can serve as ligands for the aryl hydrocarbon receptor (AhR) that induces expression of certain isozymes in the cytochrome P-450 superfamily, such as CYP1A1 and CYP1B1, localized in specific lung cell types. Although AhR activation and induction has been widely studied, its context within PM exposure and impact on the developing lung is poorly understood. In response, we have developed a replicable ultrafine premixed flame particle (PFP) generating system and used in vitro and in vivo models to define PM effects on AhR activation in the developing lung. We exposed 7-day neonatal and adult rats to a single 6-h PFP exposure and determined that PFPs cause significant parenchymal toxicity in neonates. PFPs contain weak AhR agonists that upregulate AhR-xenobiotic response element activity and expression and are capable inducers of CYP1A1 and CYP1B1 expression in both ages with different spatial and temporal patterns. Neonatal CYP1A1 expression was muted and delayed compared with adults, possibly because of differences in the enzyme maturation. We conclude that the inability of neonates to sufficiently adapt in response to PFP exposure may, in part, explain their susceptibility to PFP and urban ultrafine PM.


Assuntos
Sistema Enzimático do Citocromo P-450/biossíntese , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Material Particulado/farmacologia , Silicones/farmacologia , Animais , Animais Recém-Nascidos , Hidrocarboneto de Aril Hidroxilases/biossíntese , Células Cultivadas , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1B1 , Indução Enzimática , Humanos , Pulmão/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/metabolismo , Células U937 , Regulação para Cima/efeitos dos fármacos
13.
Part Fibre Toxicol ; 10: 34, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23902943

RESUMO

BACKGROUND: Urban particulate matter (PM) has been epidemiologically correlated with multiple cardiopulmonary morbidities and mortalities, in sensitive populations. Children exposed to PM are more likely to develop respiratory infections and asthma. Although PM originates from natural and anthropogenic sources, vehicle exhaust rich in polycyclic aromatic hydrocarbons (PAH) can be a dominant contributor to the PM2.5 and PM0.1 fractions and has been implicated in the generation of reactive oxygen species (ROS). OBJECTIVES: Current studies of ambient PM are confounded by the variable nature of PM, so we utilized a previously characterized ethylene-combusted premixed flame particles (PFP) with consistent and reproducible physiochemical properties and 1) measured the oxidative potential of PFP compared to ambient PM, 2) determined the ability of PFPs to generate oxidative stress and activate the transcription factor using in vitro and ex vivo models, and 3) we correlated these responses with antioxidant enzyme expression in vivo. METHODS: We compared oxidative stress response (HMOX1) and antioxidant enzyme (SOD1, SOD2, CAT, and PRDX6) expression in vivo by performing a time-course study in 7-day old neonatal and young adult rats exposed to a single 6-hour exposure to 22.4 µg/m3 PFPs. RESULTS: We showed that PFP is a potent ROS generator that induces oxidative stress and activates Nrf2. Induction of the oxidative stress responsive enzyme HMOX1 in vitro was mediated through Nrf2 activation and was variably upregulated in both ages. Furthermore, antioxidant enzyme expression had age and lung compartment variations post exposure. Of particular interest was SOD1, which had mRNA and protein upregulation in adult parenchyma, but lacked a similar response in neonates. CONCLUSIONS: We conclude that PFPs are effective ROS generators, comparable to urban ambient PM2.5, that induce oxidative stress in neonatal and adult rat lungs. PFPs upregulate a select set of antioxidant enzymes in young adult animals, that are unaffected in neonates. We conclude that the inability of neonatal animals to upregulate the antioxidant response may, in part, explain enhanced their susceptibility to ultrafine particles, such as PFP.


Assuntos
Antioxidantes/metabolismo , Pulmão/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fuligem/toxicidade , Fatores Etários , Animais , Animais Recém-Nascidos , Catalase/genética , Catalase/metabolismo , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/metabolismo , Humanos , Exposição por Inalação , Pulmão/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Tamanho da Partícula , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Fatores de Tempo , Transfecção , Células U937
14.
Phytother Res ; 27(5): 637-46, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22888009

RESUMO

Cardiovascular disease (CVD) is a category of chronic noncommunicable diseases causing high global mortality and has been a heavy social burden in many countries. In the search of chemicals that arise from natural food source, allicin is one such ingredient from garlic that was discovered with the potential to provide beneficial effects to the cardiovascular system. From the pharmacokinetic studies, allicin is known to be hydrophobic and can be readily absorbed through the cell membrane without inducing any damage to the phospholipid bilayer and then rapidly metabolized to exert pharmacological effects that are important to the cardiovascular system. It was found to provide cardio-protective effects by inducing vasorelaxation and alleviating various pathological conditions of CVD, including cardiac hypertrophy, angiogenesis, platelet aggregation, hyperlipidemia and hyperglycemia. Allicin was also discovered to further protect the cardiovascular system by enhancing the antioxidant status by lowering the level of reactive oxygen species and stimulating the production of glutathione. Other pharmacological benefits such as anticancer and antimicrobial activities were also discussed. It is concluded that allicin can be potentially developed into a health product for the cardiovascular system.


Assuntos
Antioxidantes/farmacologia , Cardiotônicos/farmacologia , Doenças Cardiovasculares/prevenção & controle , Ácidos Sulfínicos/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Dissulfetos , Sequestradores de Radicais Livres/farmacologia , Alho/química , Humanos , Hiperglicemia/prevenção & controle , Hiperlipidemias/prevenção & controle , Inibidores da Agregação Plaquetária/farmacologia , Ácidos Sulfínicos/farmacocinética , Vasodilatadores/farmacologia
15.
Front Mol Neurosci ; 16: 1168948, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122628

RESUMO

Background: Autophagy is a conserved physiological intracellular mechanism responsible for the degradation and recycling of cytoplasmic constituents (e.g., damaged organelles, and protein aggregates) to maintain cell homeostasis. Aberrant autophagy has been observed in neurodegenerative diseases, including Alzheimer's Disease (AD), Parkinson's Disease (PD), Amyotrophic Lateral Sclerosis (ALS), and Huntington's Disease (HD), and recently aberrant autophagy has been associated with mood disorders, such as depression. Several in vitro methods have been developed to study the complex and tightly regulated mechanisms of autophagy. In vitro methods applied to autophagy research are used to identify molecular key players involved in dysfunctional autophagy and to screen autophagy regulators with therapeutic applications in neurological diseases and mood disorders. Therefore, the aims of this narrative review are (1) to compile information on the cell-based methods used in autophagy research, (2) to discuss their application, and (3) to create a catalog of traditional and novel in vitro methods applied in neurodegenerative diseases and depression. Methods: Pubmed and Google Scholar were used to retrieve relevant in vitro studies on autophagy mechanisms in neurological diseases and depression using a combination of search terms per mechanism and disease (e.g., "macroautophagy" and "Alzheimer's disease"). A total of 37 studies were included (14 in PD, 8 in AD, 5 in ALS, 5 in %, and 5 in depression). Results: A repertoire of traditional and novel approaches and techniques was compiled and discussed. The methods used in autophagy research focused on the mechanisms of macroautophagy, microautophagy, and chaperone-mediated autophagy. The in vitro tools presented in this review can be applied to explore pathophysiological mechanisms at a molecular level and to screen for potential therapeutic agents and their mechanism of action, which can be of great importance to understanding disease biology and potential therapeutic options in the context of neurodegenerative disorders and depression. Conclusion: This is the first review to compile, discuss, and provide a catalog of traditional and novel in vitro models applied to neurodegenerative disorders and depression.

16.
Diagn Cytopathol ; 51(9): 554-562, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37288984

RESUMO

BACKGROUND: Obtaining a diagnosis and treating pulmonary malignancies during the same anesthesia requires either an on-site pathologist or a system for remotely evaluating microscopic images. Cytology specimens are challenging to remotely assess given the need to navigate through dispersed and three-dimensional cell clusters. Remote navigation is possible using robotic telepathology, but data are limited on the ease of use of current systems, particularly for pulmonary cytology. METHODS: Air dried modified Wright-Giemsa stained slides from 26 touch preparations of transbronchial biopsies and 27 smears of endobronchial ultrasound guided fine needle aspirations were scored for ease of adequacy assessment and ease of diagnosis on robotic (rmtConnect Microscope) and non-robotic telecytology platforms. Diagnostic classifications were compared between glass slides and the robotic and non-robotic telecytology assessments. RESULTS: Compared to non-robotic telecytology, robotic telecytology had a greater ease of adequacy assessment and non-inferior ease of diagnosis. The median time to diagnosis using robotic telecytology was 85 s (range 28-190 s). Diagnostic categories were concordant for 76% of cases in robotic versus non-robotic telecytology and 78% of cases in robotic telecytology versus glass slide diagnosis. Weighted Cohen's kappa scores for agreement in these comparisons were 0.84 and 0.72, respectively. CONCLUSIONS: Use of a remote-controlled robotic microscope improved the ease of adequacy assessment compared to non-robotic telecytology and enabled strongly concordant diagnoses to be expediently rendered. This study provides evidence that modern robotic telecytology is a feasible and user-friendly method of remotely and potentially intraoperatively rendering adequacy assessments and diagnoses on bronchoscopic cytology specimens.


Assuntos
Microscopia , Telepatologia , Humanos , Citodiagnóstico/métodos , Técnicas Citológicas/métodos , Biópsia por Agulha Fina/métodos , Telepatologia/métodos
17.
Front Cell Dev Biol ; 10: 982549, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187492

RESUMO

The process of neurogenesis in the brain, including cell proliferation, differentiation, survival, and maturation, results in the formation of new functional neurons. During embryonic development, neurogenesis is crucial to produce neurons to establish the nervous system, but the process persists in certain brain regions during adulthood. In adult neurogenesis, the production of new neurons in the hippocampus is accomplished via the division of neural stem cells. Neurogenesis is regulated by multiple factors, including gene expression at a temporal scale and post-transcriptional modifications. RNA-binding Proteins (RBPs) are known as proteins that bind to either double- or single-stranded RNA in cells and form ribonucleoprotein complexes. The involvement of RBPs in neurogenesis is crucial for modulating gene expression changes and posttranscriptional processes. Since neurogenesis affects learning and memory, RBPs are closely associated with cognitive functions and emotions. However, the pathways of each RBP in adult neurogenesis remain elusive and not clear. In this review, we specifically summarize the involvement of several RBPs in adult neurogenesis, including CPEB3, FXR2, FMRP, HuR, HuD, Lin28, Msi1, Sam68, Stau1, Smaug2, and SOX2. To understand the role of these RBPs in neurogenesis, including cell proliferation, differentiation, survival, and maturation as well as posttranscriptional gene expression, we discussed the protein family, structure, expression, functional domain, and region of action. Therefore, this narrative review aims to provide a comprehensive overview of the RBPs, their function, and their role in the process of adult neurogenesis as well as to identify possible research directions on RBPs and neurogenesis.

18.
Front Cell Dev Biol ; 10: 1062807, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699006

RESUMO

Background and objective: Prediction of poststroke recovery can be expressed by prognostic biomarkers that are related to the pathophysiology of stroke at the cellular and molecular level as well as to the brain structural and functional reserve after stroke at the systems neuroscience level. This study aimed to review potential biomarkers that can predict poststroke functional recovery. Methods: A narrative review was conducted to qualitatively summarize the current evidence on biomarkers used to predict poststroke functional recovery. Results: Neurophysiological measurements and neuroimaging of the brain and a wide diversity of molecules had been used as prognostic biomarkers to predict stroke recovery. Neurophysiological studies using resting-state electroencephalography (EEG) revealed an interhemispheric asymmetry, driven by an increase in low-frequency oscillation and a decrease in high-frequency oscillation in the ipsilesional hemisphere relative to the contralesional side, which was indicative of individual recovery potential. The magnitude of somatosensory evoked potentials and event-related desynchronization elicited by movement in task-related EEG was positively associated with the quantity of recovery. Besides, transcranial magnetic stimulation (TMS) studies revealed the potential values of using motor-evoked potentials (MEP) and TMS-evoked EEG potentials from the ipsilesional motor cortex as prognostic biomarkers. Brain structures measured using magnetic resonance imaging (MRI) have been implicated in stroke outcome prediction. Specifically, the damage to the corticospinal tract (CST) and anatomical motor connections disrupted by stroke lesion predicted motor recovery. In addition, a wide variety of molecular, genetic, and epigenetic biomarkers, including hemostasis, inflammation, tissue remodeling, apoptosis, oxidative stress, infection, metabolism, brain-derived, neuroendocrine, and cardiac biomarkers, etc., were associated with poor functional outcomes after stroke. However, challenges such as mixed evidence and analytical concerns such as specificity and sensitivity have to be addressed before including molecular biomarkers in routine clinical practice. Conclusion: Potential biomarkers with prognostic values for the prediction of functional recovery after stroke have been identified; however, a multimodal approach of biomarkers for prognostic prediction has rarely been studied in the literature. Future studies may incorporate a combination of multiple biomarkers from big data and develop algorithms using data mining methods to predict the recovery potential of patients after stroke in a more precise way.

19.
Psychoneuroendocrinology ; 129: 105267, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34015682

RESUMO

The hypothalamic-pituitary-adrenal (HPA) and parasympathetic nervous systems have been reported to play important roles in emotion regulation and stress coping. Yet, their direct relationship with psychological resilience remains unclear. These biophysiological features should be considered together with the traditional psychometric properties in studying resilience more comprehensively. The current study aimed to examine the role of these systems during a laboratory stress task and to determine the prediction power of resilience by combining psychological and biophysiological features. One hundred and seven (52 females) university students without psychiatric disorders underwent the Trier Social Stress Task (TSST). Psychometric properties of resilience were measured at rest; vagal heart rate variability (HRV), salivary cortisol, and dehydroepiandrosterone (DHEA) levels were captured at baseline, during, and after TSST. Multivariate linear regression as well as support vector regression machine-learning analyses were performed to investigate significant predictors and the prediction power of resilience. Results showed that positive and negative affects, HRV during the anticipatory phase of stress, and the ratio of cortisol/DHEA at the first recovery time point were significant predictors of resilience. The addition of biophysiological features increased the prediction power of resilience by 1.2-fold compared to psychological features alone. Results from machine learning analyses further demonstrated that the increased prediction power of resilience by adding the ratio of cortisol/DHEA was significant in "cortisol responders"; whereas a trend level was observed in "cortisol non-responders". Our findings extend the knowledge from the literature that high vagal activity during the anticipating phase of stress and the ability to restore the balance between cortisol and DHEA after a stress event could be an important feature in predicting resilience. Our findings also further support the need of combining psychological and biophysiological features in studying/predicting resilience.


Assuntos
Desidroepiandrosterona , Hidrocortisona , Resiliência Psicológica , Estresse Psicológico , Biomarcadores/metabolismo , Desidroepiandrosterona/metabolismo , Feminino , Humanos , Hidrocortisona/metabolismo , Masculino , Resiliência Psicológica/fisiologia , Saliva/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia
20.
Inhal Toxicol ; 22 Suppl 2: 70-83, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20961279

RESUMO

Current studies of particulate matter (PM) are confounded by the fact that PM is a complex mixture of primary (crustal material, soot, metals) and secondary (nitrates, sulfates, and organics formed in the atmosphere) compounds with considerable variance in composition by sources and location. We have developed a laboratory-based PM that is replicable, does not contain dust or metals and that can be used to study specific health effects of PM composition in animal models. We exposed both neonatal (7 days of age) and adult rats to a single 6-h exposure of laboratory generated fine diffusion flame particles (DFP; 170 µg/m(3)), or filtered air. Pulmonary gene and protein expression as well as indicators of cytotoxicity were evaluated 24 h after exposure. Although DFP exposure did not alter airway epithelial cell composition in either neonates or adults, increased lactate dehydrogenase activity was found in the bronchoalveolar lavage fluid of neonates indicating an age-specific increase in susceptibility. In adults, 16 genes were differentially expressed as a result of DFP exposure whereas only 6 genes were altered in the airways of neonates. Glutamate cysteine ligase protein was increased in abundance in both DFP exposed neonates and adults indicating an initiation of antioxidant responses involving the synthesis of glutathione. DFP significantly decreased catalase gene expression in adult airways, although catalase protein expression was increased by DFP in both neonates and adults. We conclude that key airway antioxidant enzymes undergo changes in expression in response to a moderate PM exposure that does not cause frank epithelial injury and that neonates have a different response pattern than adults.


Assuntos
Antioxidantes/metabolismo , Inalação , Pulmão/patologia , Material Particulado/toxicidade , Sistema Respiratório/patologia , Fuligem/toxicidade , Administração por Inalação , Fatores Etários , Animais , Animais Recém-Nascidos , Líquido da Lavagem Broncoalveolar , Catalase/metabolismo , Expressão Gênica , Glutamato-Cisteína Ligase/metabolismo , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Sistema Respiratório/metabolismo
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