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1.
J Allergy Clin Immunol ; 141(2): 560-570, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28528200

RESUMO

BACKGROUND: Sputum analysis in asthmatic patients is used to define airway inflammatory processes and might guide therapy. OBJECTIVE: We sought to determine differential gene and protein expression in sputum samples from patients with severe asthma (SA) compared with nonsmoking patients with mild/moderate asthma. METHODS: Induced sputum was obtained from nonsmoking patients with SA, smokers/ex-smokers with severe asthma, nonsmoking patients with mild/moderate asthma (MMAs), and healthy nonsmoking control subjects. Differential cell counts, microarray analysis of cell pellets, and SOMAscan analysis of sputum analytes were performed. CRID3 was used to inhibit the inflammasome in a mouse model of SA. RESULTS: Eosinophilic and mixed neutrophilic/eosinophilic inflammation were more prevalent in patients with SA compared with MMAs. Forty-two genes probes were upregulated (>2-fold) in nonsmoking patients with severe asthma compared with MMAs, including IL-1 receptor (IL-1R) family and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NRLP3) inflammasome members (false discovery rate < 0.05). The inflammasome proteins nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 1 (NLRP1), NLRP3, and nucleotide-binding oligomerization domain (NOD)-like receptor C4 (NLRC4) were associated with neutrophilic asthma and with sputum IL-1ß protein levels, whereas eosinophilic asthma was associated with an IL-13-induced TH2 signature and IL-1 receptor-like 1 (IL1RL1) mRNA expression. These differences were sputum specific because no activation of NLRP3 or enrichment of IL-1R family genes in bronchial brushings or biopsy specimens in patients with SA was observed. Expression of NLRP3 and of the IL-1R family genes was validated in the Airway Disease Endotyping for Personalized Therapeutics cohort. Inflammasome inhibition using CRID3 prevented airway hyperresponsiveness and airway inflammation (both neutrophilia and eosinophilia) in a mouse model of severe allergic asthma. CONCLUSION: IL1RL1 gene expression is associated with eosinophilic SA, whereas NLRP3 inflammasome expression is highest in patients with neutrophilic SA. TH2-driven eosinophilic inflammation and neutrophil-associated inflammasome activation might represent interacting pathways in patients with SA.


Assuntos
Asma/imunologia , Perfilação da Expressão Gênica , Receptores de Interleucina-1/imunologia , Escarro/imunologia , Regulação para Cima/imunologia , Adulto , Animais , Asma/patologia , Eosinófilos/imunologia , Eosinófilos/patologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/patologia , Células Th2/imunologia , Células Th2/patologia
2.
Biochim Biophys Acta ; 1843(7): 1259-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24637330

RESUMO

HMG-CoA reductase, the proximal rate-limiting enzyme in the mevalonate pathway, is inhibited by statins. Beyond their cholesterol lowering impact, statins have pleiotropic effects and their use is linked to improved lung health. We have shown that mevalonate cascade inhibition induces apoptosis and autophagy in cultured human airway mesenchymal cells. Here, we show that simvastatin also induces endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) in these cells. We tested whether coordination of ER stress, autophagy and apoptosis determines survival or demise of human lung mesenchymal cells exposed to statin. We observed that simvastatin exposure activates UPR (activated transcription factor 4, activated transcription factor 6 and IRE1α) and caspase-4 in primary human airway fibroblasts and smooth muscle cells. Exogenous mevalonate inhibited apoptosis, autophagy and UPR, but exogenous cholesterol was without impact, indicating that sterol intermediates are involved with mechanisms mediating statin effects. Caspase-4 inhibition decreased simvastatin-induced apoptosis, whereas inhibition of autophagy by ATG7 or ATG3 knockdown significantly increased cell death. In BAX(-/-)/BAK(-/-) murine embryonic fibroblasts, simvastatin-triggered apoptotic and UPR events were abrogated, but autophagy flux was increased leading to cell death via necrosis. Our data indicate that mevalonate cascade inhibition, likely associated with depletion of sterol intermediates, can lead to cell death via coordinated apoptosis, autophagy, and ER stress. The interplay between these pathways appears to be principally regulated by autophagy and Bcl-2-family pro-apoptotic proteins. These findings uncover multiple mechanisms of action of statins that could contribute to refining the use of such agent in treatment of lung disease.


Assuntos
Autofagia/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Ácido Mevalônico/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína X Associada a bcl-2/genética , Animais , Apoptose/efeitos dos fármacos , Proteína 7 Relacionada à Autofagia , Proteínas Relacionadas à Autofagia , Brônquios/citologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Caspases Iniciadoras/genética , Caspases Iniciadoras/metabolismo , Sobrevivência Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Camundongos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Sinvastatina/farmacologia , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/antagonistas & inibidores , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Resposta a Proteínas não Dobradas/genética , Proteína Killer-Antagonista Homóloga a bcl-2/deficiência , Proteína X Associada a bcl-2/deficiência
3.
Am J Physiol Lung Cell Mol Physiol ; 309(11): L1354-66, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26432865

RESUMO

High mobility group box 1 (HMGB1) is a damage-associated molecular pattern (DAMP) protein that binds Toll-like receptors (e.g., TLR4) and the receptor for advanced glycated end products (RAGE). The direct effects of HMGB1 on airway structural cells are not fully known. As epithelial cell responses are fundamental drivers of asthma, including abnormal repair-restitution linked to changes in extracellular matrix (ECM) synthesis, we tested the hypothesis that HMGB1 promotes bronchial epithelial cell wound repair via TLR4 and/or RAGE signaling that regulates ECM (fibronectin and the γ2-chain of laminin-5) and integrin protein abundance. To assess impact of HMGB1 we used molecular and pharmacological inhibitors of RAGE or TLR4 signaling in scratch wound, immunofluorescence, and immunoblotting assays to assess wound repair, ECM synthesis, and phosphorylation of intracellular signaling. HMGB1 increased wound closure, and this effect was attenuated by blocking RAGE and TLR4 signaling. HMGB1-induced fibronectin and laminin-5 (γ2 chain) was diminished by blocking RAGE and/or blunting TLR4 signaling. Similarly, induction of α3-integrin receptor for fibronectin and laminin-5 was also diminished by blocking TLR4 signaling and RAGE. Lastly, rapid and/or sustained phosphorylation of SMAD2, ERK1/2, and JNK signaling modulated HMGB1-induced wound closure. Our findings suggest a role for HMGB1 in human airway epithelial cell repair and restitution via multiple pathways mediated by TLR4 and RAGE that underpin increased ECM synthesis and modulation of cell-matrix adhesion.


Assuntos
Brônquios/patologia , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Proteína HMGB1/metabolismo , Cicatrização , Idoso , Animais , Linhagem Celular , Proteínas da Matriz Extracelular/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Biossíntese de Proteínas , Doença Pulmonar Obstrutiva Crônica/patologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Proteína Smad2/metabolismo , Doadores de Tecidos , Receptor 4 Toll-Like/metabolismo
4.
Am J Physiol Lung Cell Mol Physiol ; 308(12): L1253-64, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25888577

RESUMO

Human airway smooth muscle (HASM) exhibits enhanced contractility in asthma. Inflammation is associated with airway hypercontractility, but factors that underpin these features are not fully elucidated. Glutamate toxicity associated with increased plasma glutamate concentrations was observed in airway inflammation, suggesting that multisubunit glutamate receptors, N-methyl-d-aspartate receptors (NMDA-R) contribute to airway hyperreactivity. We tested the hypothesis that HASM expresses NMDA-R subunits that can form functional receptors to mediate contractile responses to specific extracellular ligands. In cultured HASM cells, we measured NMDA-R subunit mRNA and protein abundance by quantitative PCR, immunoblotting, flow cytometry, and epifluorescence immunocytochemistry. We measured mRNA for a number of NMDA-R subunits, including the obligatory NR1 subunit, which we confirmed to be present as a protein. In vitro and ex vivo functional NMDA-R activation in HASM cells was measured using intracellular calcium flux (fura-2 AM), collagen gel contraction assays, and murine thin-cut lung slices (TCLS). NMDA, a pharmacological glutamate analog, induced cytosolic calcium mobilization in cultured HASM cells. We detected three different temporal patterns of calcium response, suggesting the presence of heterogeneous myocyte subpopulations. NMDA-R activation also induced airway contraction in murine TCLS and soft collagen gels seeded with HASM cells. Responses in cells, lung slices, and collagen gels were mediated by NMDA-R, as they could be blocked by (2R)-amino-5-phosphonopentanoate, a specific NMDA-R inhibitor. In summary, we reveal the presence of NMDA-R in HASM that mediate contractile responses via glutamatergic mechanisms. These findings suggest that accumulation of glutamate-like ligands for NMDA-R associated with airway inflammation contributes directly to airway hyperreactivity.


Assuntos
Contração Muscular/fisiologia , Miócitos de Músculo Liso/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Sistema Respiratório/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Células Cultivadas , Feminino , Citometria de Fluxo , Fura-2/metabolismo , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos BALB C , Miócitos de Músculo Liso/citologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de N-Metil-D-Aspartato/genética , Sistema Respiratório/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Am J Physiol Lung Cell Mol Physiol ; 307(10): L765-74, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25217661

RESUMO

Emerging epidemiological evidence reveals a link between lung disease and exposure to indoor pollutants such as perfluorinated compounds (PFCs). PFC exposure during critical developmental stages may increase asthma susceptibility. Thus, in a murine model, we tested the hypothesis that early life and continued exposure to two ubiquitous household PFCs, perfluorooctanoic acid (PFOA) and perflurooctanesulfonic acid (PFOS), can induce lung dysfunction that exacerbates allergen-induced airway hyperresponsiveness (AHR) and inflammation. Balb/c mice were exposed to PFOA or PFOS (4 mg/kg chow) from gestation day 2 to 12 wk of age by feeding pregnant and nursing dams, and weaned pups. Some pups were also sensitized and challenged with ovalbumin (OVA). We assessed lung function and inflammatory cell and cytokine expression in the lung and examined bronchial goblet cell number. PFOA, but not PFOS, without the OVA sensitization/challenge induced AHR concomitant with a 25-fold increase of lung macrophages. PFOA exposure did not affect OVA-induced lung inflammatory cell number. In contrast, PFOS exposure inhibited OVA-induced lung inflammation, decreasing total cell number in lung lavage by 68.7%. Interferon-γ mRNA in the lung was elevated in all PFC-exposed groups. Despite these effects, neither PFOA nor PFOS affected OVA-induced AHR. Our data do not reveal PFOA or PFOS exposure as a risk factor for more severe allergic asthma-like symptoms, but PFOA alone can induce airway inflammation and alter airway function.


Assuntos
Poluentes Atmosféricos/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Asma/imunologia , Caprilatos/toxicidade , Fluorocarbonos/toxicidade , Células Caliciformes/imunologia , Pulmão/imunologia , Exposição Materna/efeitos adversos , Animais , Asma/induzido quimicamente , Asma/patologia , Feminino , Células Caliciformes/patologia , Interferon gama/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Gravidez
7.
Pulm Pharmacol Ther ; 29(2): 121-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24747433

RESUMO

Chronic obstructive pulmonary disease (COPD) is currently the fourth leading cause of death worldwide and, in contrast to the trend for cardiovascular diseases, mortality rates still continue to climb. This increase is in part due to an aging population, being expanded by the "Baby boomer" generation who grew up when smoking rates were at their peak and by people in developing countries living longer. Sadly, there has been a disheartening lack of new therapeutic approaches to counteract the progressive decline in lung function associated with the disease that leads to disability and death. COPD is characterized by irreversible chronic airflow limitation that is caused by emphysematous destruction of lung elastic tissue and/or obstruction in the small airways due to occlusion of their lumen by inflammatory mucus exudates, narrowing and obliteration. These lesions are mainly produced by the response of the tissue to the repetitive inhalational injury inflicted by noxious gases, including cigarette smoke, which involves interaction between infiltrating inflammatory immune cells, resident cells (e.g. epithelial cells and fibroblasts) and the extra cellular matrix. This interaction leads to tissue destruction and airway remodeling with changes in elastin and collagen, such that the epithelial-mesenchymal trophic unit is dysregulated in both the disease pathologies. This review focuses on: 1--novel inflammatory and remodeling factors that are altered in COPD; 2--in vitro and in vivo models to understand the mechanism whereby the extra cellular matrix environment in altered in COPD; and 3--COPD in the context of wound-repair tissue responses, with a focus on the regulation of mesenchymal cell fate and phenotype.


Assuntos
Pulmão/patologia , Células-Tronco Mesenquimais/fisiologia , Doença Pulmonar Obstrutiva Crônica/patologia , Animais , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Pulmão/citologia , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Transdução de Sinais/fisiologia
8.
Pulm Pharmacol Ther ; 26(1): 112-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22634112

RESUMO

Agonists activating ß(2)-adrenoceptors (ß(2)ARs) on airway smooth muscle (ASM) are the drug of choice for rescue from acute bronchoconstriction in patients with both asthma and chronic obstructive pulmonary disease (COPD). Moreover, the use of long-acting ß-agonists combined with inhaled corticosteroids constitutes an important maintenance therapy for these diseases. ß-Agonists are effective bronchodilators due primarily to their ability to antagonize ASM contraction. The presumed cellular mechanism of action involves the generation of intracellular cAMP, which in turn can activate the effector molecules cAMP-dependent protein kinase (PKA) and Epac. Other agents such as prostaglandin E(2) and phosphodiesterase inhibitors that also increase intracellular cAMP levels in ASM, can also antagonize ASM contraction, and inhibit other ASM functions including proliferation and migration. Therefore, ß(2)ARs and cAMP are key players in combating the pathophysiology of airway narrowing and remodeling. However, limitations of ß-agonist therapy due to drug tachyphylaxis related to ß(2)AR desensitization, and recent findings regarding the manner in which ß(2)ARs and cAMP signal, have raised new and interesting questions about these well-studied molecules. In this review we discuss current concepts regarding ß(2)ARs and cAMP in the regulation of ASM cell functions and their therapeutic roles in asthma and COPD.


Assuntos
Asma/fisiopatologia , AMP Cíclico/metabolismo , Músculo Liso/metabolismo , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Animais , Asma/tratamento farmacológico , Broncoconstrição/efeitos dos fármacos , Quimioterapia Combinada , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Músculo Liso/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Receptores Adrenérgicos beta 2/metabolismo
9.
Pulm Pharmacol Ther ; 26(1): 132-44, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22981423

RESUMO

Asthma is characterized in part by variable airflow obstruction and non-specific hyperresponsiveness to a variety of bronchoconstrictors, both of which are mediated by the airway smooth muscle (ASM). The ASM is also involved in the airway inflammation and airway wall remodeling observed in asthma. For all these reasons, the ASM provides an important target for the treatment of asthma. Several classes of drugs were developed decades ago which targeted the ASM - including ß-agonists, anti-cholinergics, anti-histamines and anti-leukotrienes - but no substantially new class of drug has appeared recently. In this review, we summarize the on-going work of several laboratories aimed at producing novel targets and/or tools for the treatment of asthma. These range from receptors and ion channels on the ASM plasmalemma, to intracellular effectors (particularly those related to cyclic nucleotide signaling, calcium-homeostasis and phosphorylation cascades), to anti-IgE therapy and outright destruction of the ASM itself.


Assuntos
Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Músculo Liso/efeitos dos fármacos , Obstrução das Vias Respiratórias/tratamento farmacológico , Obstrução das Vias Respiratórias/patologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Animais , Asma/fisiopatologia , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/fisiopatologia , Desenho de Fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Terapia de Alvo Molecular , Músculo Liso/metabolismo
10.
Pulm Pharmacol Ther ; 26(1): 42-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22939888

RESUMO

The biological responses of airway smooth muscle (ASM) are diverse, in part due to ASM phenotype plasticity. ASM phenotype plasticity refers to the ability of ASM cells to change the degree of a variety of functions, including contractility, proliferation, migration and secretion of inflammatory mediators. This plasticity occurs due to intrinsic or acquired abnormalities in ASM cells, and these abnormalities or predisposition of the ASM cell may alter the ASM response and in some cases recapitulate disease hallmarks of asthma. These phenotypic changes are ultimately determined by multiple stimuli and occur due to alterations in the intricate balance or reversible state that maintains ASM cells in either a contractile or synthetic state, through processes termed maturation or modulation, respectively. To elucidate the role of ASM phenotype in disease states, numerous in vitro studies have suggested a phenotypic switch in ASM primary cell cultures as an explanation for the plethora of responses mediated by ASM cells. Moreover, there is overwhelming evidence suggesting that the immunomodulatory response of ASM is due to the acquisition of a synthetic phenotype; however, whether this degree of plasticity is present in vivo as opposed to cell culture-based models remains speculative. Nonetheless, this review will give an overall scope of ASM phenotypic markers, triggers of ASM phenotype modulation and novel therapeutic approaches to control ASM phenotype plasticity.


Assuntos
Asma/fisiopatologia , Músculo Liso/patologia , Miócitos de Músculo Liso/patologia , Animais , Movimento Celular , Proliferação de Células , Humanos , Mediadores da Inflamação/metabolismo , Contração Muscular/fisiologia , Músculo Liso/citologia , Músculo Liso/metabolismo , Miócitos de Músculo Liso/metabolismo , Fenótipo
11.
Pulm Pharmacol Ther ; 26(1): 95-104, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22921313

RESUMO

In asthma, the airway smooth muscle (ASM) cell plays a central role in disease pathogenesis through cellular changes which may impact on its microenvironment and alter ASM response and function. The answer to the long debated question of what makes a 'healthy' ASM cell become 'asthmatic' still remains speculative. What is known of an 'asthmatic' ASM cell, is its ability to contribute to the hallmarks of asthma such as bronchoconstriction (contractile phenotype), inflammation (synthetic phenotype) and ASM hyperplasia (proliferative phenotype). The phenotype of healthy or diseased ASM cells or tissue for the most part is determined by expression of key phenotypic markers. ASM is commonly accepted to have different phenotypes: the contractile (differentiated) state versus the synthetic (dedifferentiated) state (with the capacity to synthesize mediators, proliferate and migrate). There is now accumulating evidence that the synthetic functions of ASM in culture derived from asthmatic and non-asthmatic donors differ. Some of these differences include an altered profile and increased production of extracellular matrix proteins, pro-inflammatory mediators and adhesion receptors, collectively suggesting that ASM cells from asthmatic subjects have the capacity to alter their environment, actively participate in repair processes and functionally respond to changes in their microenvironment.


Assuntos
Asma/fisiopatologia , Inflamação/patologia , Miócitos de Músculo Liso/patologia , Animais , Broncoconstrição , Microambiente Celular , Humanos , Hiperplasia/patologia , Contração Muscular , Miócitos de Músculo Liso/metabolismo , Fenótipo
12.
Int J Gynaecol Obstet ; 163(2): 466-475, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37128764

RESUMO

Data on mpox in pregnancy are currently limited. Historically, only 65 cases in pregnancy have been reported globally since mpox was discovered in 1958. This includes 59 cases in the current outbreak. Vertical transmission was confirmed in one patient. Pregnant women are at high risk of severe disease owing to immunological and hormonal changes that increase susceptibility to infections in pregnancy. African women appear to be at higher risk of mpox infection and adverse outcomes in pregnancy for epidemiological and immunologic reasons, in addition to the background high rates of adverse feto-maternal outcomes in the region. This risk is potentially heightened during the COVID-19 pandemic due to the possibility of mpox virus exportation/importation as a result of the lifting of movement restrictions and trans-border travels between countries affected by the current outbreak. Furthermore, coinfection with mpox and COVID-19 in pregnancy is possible, and the clinical features of both conditions may overlap. Challenges of diagnosis and management of mpox in pregnancy in Africa include patients concealing their travel history from healthcare providers and absconding from/evading isolation after diagnosis, shortage of personal protective equipment and polymerase chain reaction testing facilities for diagnosis, vaccine hesitancy/resistance, and poor disease notification systems. There is a need for local, regional and global support to strengthen the capacity of African countries to address these challenges and potentially reduce the disease burden among pregnant women in the continent.


Assuntos
Mpox , Complicações Infecciosas na Gravidez , Feminino , Humanos , Gravidez , África/epidemiologia , COVID-19 , Mpox/epidemiologia , Pandemias/prevenção & controle , Gestão de Riscos , Complicações Infecciosas na Gravidez/epidemiologia
13.
Proc Natl Acad Sci U S A ; 106(26): 10775-80, 2009 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-19541629

RESUMO

Phenotypic modulation of airway smooth muscle (ASM) is an important feature of airway remodeling in asthma that is characterized by enhanced proliferation and secretion of pro-inflammatory chemokines. These activities are regulated by the concentration of free Ca(2+) in the cytosol ([Ca(2+)](i)). A rise in [Ca(2+)](i) is normalized by rapid reuptake of Ca(2+) into sarcoplasmic reticulum (SR) stores by the sarco/endoplasmic reticulum Ca(2+) (SERCA) pump. We examined whether increased proliferative and secretory responses of ASM from asthmatics result from reduced SERCA expression. ASM cells were cultured from subjects with and without asthma. SERCA expression was evaluated by western blot, immunohistochemistry and real-time PCR. Changes in [Ca(2+)](i), cell spreading, cellular proliferation, and eotaxin-1 release were measured. Compared with control cells from healthy subjects, SERCA2 mRNA and protein expression was reduced in ASM cells from subjects with moderately severe asthma. SERCA2 expression was similarly reduced in ASM in vivo in subjects with moderate/severe asthma. Rises in [Ca(2+)](i) following cell surface receptor-induced SR activation, or inhibition of SERCA-mediated Ca(2+) re-uptake, were attenuated in ASM cells from asthmatics. Likewise, the return to baseline of [Ca](i) after stimulation by bradykinin was delayed by approximately 50% in ASM cells from asthmatics. siRNA-mediated knockdown of SERCA2 in ASM from healthy subjects increased cell spreading, eotaxin-1 release and proliferation. Our findings implicate a deficiency in SERCA2 in ASM in asthma that contributes to its secretory and hyperproliferative phenotype in asthma, and which may play a key role in mechanisms of airway remodeling.


Assuntos
Asma/metabolismo , Brônquios/metabolismo , Retículo Sarcoplasmático/enzimologia , Asma/patologia , Asma/fisiopatologia , Western Blotting , Brônquios/patologia , Brônquios/fisiopatologia , Cálcio/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Quimiocina CCL11/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Homeostase , Humanos , Imuno-Histoquímica , Interleucina-13/farmacologia , Masculino , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático
14.
Afr J Prim Health Care Fam Med ; 13(1): e1-e6, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34636604

RESUMO

BACKGROUND: The antepartum estimation of foetal weight is a major determinant of the route of delivery and this has become vital in modern day obstetrics. The limitations to the use of obstetric ultrasonography, considered as the gold standard in estimating foetal weight, make clinical estimation methods attractive alternatives, especially in resource- constrained settings where many un-booked women may report for delivery. AIM: To determine the reliability of intrapartum clinical foetal weight estimation in predicting the actual birth weight (ABW) and route of delivery among term parturient. SETTING: The study was conducted at the Sacred Heart Hospital, Lantoro, a voluntary mission agency hospital in Southwest Nigeria. METHODS: This cross-sectional study was conducted among 291 term parturient recruited by systematic random sampling between June and September 2017. The clinical estimation of foetal weight was carried out using Johnson's formula. RESULTS: The accuracy of Johnson's formula to predict the ABW was 59.5%; while for the mode of delivery, it was 130 (75.1%) for spontaneous vaginal delivery (SVD) and 43 (24.9%) for caesarean section (CS). The sensitivity of the accuracy of Johnson's formula to predict the mode of delivery was 75.1%, with a specificity of 35.6%, a positive predictive value (PPV) of 63.1%, and a negative predictive value (NPV) of 49.4%. CONCLUSION: The intrapartum clinical foetal weight estimation at term determined by Johnson's formula was reliably predictive of ABW and SVD, but it was unreliable in predicting the need for a CS.


Assuntos
Cesárea , Peso Fetal , Estudos Transversais , Feminino , Hospitais , Humanos , Nigéria , Gravidez , Reprodutibilidade dos Testes
15.
Thorax ; 65(6): 547-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20522856

RESUMO

Asthma is characterised by airway hyper-responsiveness and remodelling, and there is mounting evidence that alterations in the phenotype of airway smooth muscle (ASM) play a central role in these processes. Although the concept that dysregulation of ASM Ca(2+) homeostasis may underlie at least part of these alterations has been around for many years, it is only relatively recently that the availability of ASM biopsies from subjects with mild and moderate asthma has allowed it to be properly investigated. In this article, critical components of the pathobiology of asthmatic ASM, including contractile function, proliferation, cell migration and secretion of proinflammatory cytokines and chemokines, are reviewed and related to associated changes in ASM Ca(2+) homeostasis. Based on this evidence, it is proposed that a unifying mechanism for the abnormal asthmatic phenotype is dysregulation of Ca(2+) homeostasis caused at least in part by a downregulation in expression and function of sarcoendoplasmic Ca(2+) ATPases (SERCAs).


Assuntos
Remodelação das Vias Aéreas/fisiologia , Asma/fisiopatologia , Cálcio/metabolismo , Músculo Liso/fisiopatologia , Citocinas/metabolismo , Homeostase/fisiologia , Humanos , Contração Muscular/fisiologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/fisiologia
16.
S Afr Fam Pract (2004) ; 62(1): e1-e10, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32896139

RESUMO

BACKGROUND: For many decades, hypertension guidelines recommended dual-arm blood pressure measurement. However, this practice is poor in Nigeria and its significance is largely unidentified. Hence, this study was done to determine the point prevalence of inter-arm blood pressure difference and its relationship with hypertension and diabetes mellitus. METHODS: A cross-sectional study was conducted among 214 respondents at the general outpatient clinic of a tertiary hospital in Nigeria. Demographic characteristics and anthropometric indices were obtained. Blood pressure readings were obtained through sequentially repeated measurements in respondents' arms. RESULTS: One-hundred and eighty-six respondents had complete data given a completion rate of 86.9%. Systolic blood pressure was higher on the right and left arm in 102 (54.8%) and 56 (30.1%) of the respondents, respectively. Diastolic blood pressure was higher on the right and left arm in 73 (39.2%) and 63 (33.9%) of the respondents, respectively. The overall prevalence of significant systolic inter-arm difference (≥ 10 mmHg) and diastolic inter-arm difference (≥ 10 mmHg) were 24.2% and 18.8%, respectively. Significant systolic inter-arm difference (p = 0.033) and diastolic inter-arm difference (p = 0.01) were significantly more among respondents with hypertension and/or diabetes mellitus. CONCLUSION: The blood pressure readings in both arms were different among the majority of the respondents, being higher on the right arm in many of them. The prevalence of significant inter-arm difference was high in the unselected primary care patients studied especially among patients with hypertension and/or diabetes mellitus. Blood pressure measurement in both arms should become a routine practice during initial patients' visits in primary care.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Adulto , Instituições de Assistência Ambulatorial , Estudos Transversais , Diabetes Mellitus/diagnóstico , Medicina de Família e Comunidade , Humanos , Nigéria , Estado Pré-Diabético/diagnóstico
17.
S Afr Fam Pract (2004) ; 62(1): e1-e11, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32242434

RESUMO

BACKGROUND: A significant difference in the blood pressure (BP) value of a patient taken by different health workers has been a subject of discussion among health workers. This study investigated the variations between usual-care and guideline-concordant BP measurement protocols and evaluated the implications of the disparities on diagnosis and treatment decision. METHODS: A cross-sectional study was conducted among 206 participants. The usual-care and guideline-concordant BP readings taken from each participant by the regular clinic nurses and research-trained nurses, respectively, were obtained. RESULTS: Majority of the regular clinic nurses following the usual-care protocol used the left arm for BP measurement (59.7%). The systolic BP (SBP) and diastolic BP (DBP) readings were higher on the right arm in 55.3% and 39.2% of the participants, respectively. The mean guideline-concordant BP was 7.67 mmHg higher than the mean usual-care for SBP (p ≤ 0.05) and 7.14 mmHg higher for DBP (p ≤ 0.05). The proportion of participants classified as having hypertension and uncontrolled BP was 11.8% and 15.0% lower when using usual-care BP compared to guideline-concordant BP, respectively. Fifty-one (24.8%) respondents were advised incorrect treatment based on usual-care BP measurement. The Bland-Altman plot showed that limits of agreement were wider than within the 10 mmHg clinical reference range and unacceptable for clinical purposes. CONCLUSION: The usual-care and guideline-concordant BP measurement protocols were significantly different, and the disparity had significant consequences on the diagnosis and treatment of hypertension. Health workers should strictly adhere to the guidelines on BP measurement to avoid mismanagement of patients.


Assuntos
Determinação da Pressão Arterial , Atenção Primária à Saúde , Pressão Sanguínea , Estudos Transversais , Humanos , Nigéria
18.
Biosci Rep ; 37(6)2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-28842514

RESUMO

Chronic cough is associated with airway inflammation and remodelling. Abnormal airway smooth muscle cell (ASMC) function may underlie mechanisms of chronic cough. Our objective was to examine the transcriptome and focused secretome of ASMCs from chronic cough patients and healthy non-cough volunteers. ASMC gene expression profiling was performed at baseline and/or after stimulation with polyinosinic:polycytidylic acid (poly(I:C)) to mimic viral infection. Supernatants were collected for multiplex analysis. Our results showed no significant differentially expressed genes (DEGs, false discovery rate (FDR) <0.05) between chronic cough and healthy non-cough ASMCs at baseline. Poly(I:C) stimulation resulted in 212 DEGs (>1.5 fold-change, FDR <0.05) in ASMCs from chronic cough patients compared with 1674 DEGs in healthy non-cough volunteers. The top up-regulated genes included chemokine (C-X-C motif) ligand (CXCL) 11 (CXCL11), CXCL10, chemokine (C-C motif) ligand (CCL) 5 (CCL5) and interferon-induced protein 44 like (IFI44L) corresponding with inflammation and innate immune response pathways. ASMCs from cough subjects had enhanced activation of viral response pathways in response to poly(I:C) compared with healthy non-cough subjects, reduced activation of pathways involved in chronic inflammation and equivalent activation of neuroregulatory genes. The poly(I:C)-induced release of inflammatory mediators, including CXCL8, interleukin (IL)-6 and CXCL1, from ASMCs from cough patients was significantly impaired compared with healthy non-cough subjects. Addition of fluticasone propionate (FP) to poly(I:C)-treated ASMCs resulted in greater gene expression changes in healthy non-cough ASMCs. FP had a differential effect on poly(I:C)-induced mediator release between chronic cough and healthy non-cough volunteers. In conclusion, altered innate immune and inflammatory gene profiles within ASMCs, rather than infiltrating cells or nerves, may drive the cough response following respiratory viral infection.


Assuntos
Remodelação das Vias Aéreas/genética , Tosse/imunologia , Perfilação da Expressão Gênica/métodos , Imunidade Inata/genética , Miócitos de Músculo Liso/imunologia , Remodelação das Vias Aéreas/imunologia , Anti-Inflamatórios/farmacologia , Antígenos/genética , Antígenos/metabolismo , Brônquios/citologia , Brônquios/imunologia , Brônquios/metabolismo , Broncoscopia , Doença Crônica , Citocinas/genética , Citocinas/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Feminino , Fluticasona/farmacologia , Humanos , Imunidade Inata/imunologia , Inflamação/genética , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Miócitos de Músculo Liso/metabolismo , Projetos Piloto , Poli C/farmacologia
19.
J Family Med Prim Care ; 5(3): 569-575, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28217585

RESUMO

CONTEXT: Nonadherence to therapeutic plans has been reported among hypertensive patients. Researchers have also shown that adherence to therapeutic plans improves if motivation in the form of social support is provided. There is a dearth of local studies that explore the influence of family support on treatment outcomes of hypertensive patients. AIMS: The aim of the study was to determine the relationship between BP control and perceived family support in patients with essential hypertension seen at a primary care setting in Western Nigeria. SETTINGS AND DESIGN: This was a cross-sectional hospital-based study. SUBJECTS AND METHODS: Systematic random sampling technique was used in selecting 360 hypertensive respondents between April and July 2013. Data were collected through a pretested interviewer-administered questionnaire and a standardized tool, Perceived Social Support Family Scale, which measured the respondents' level of perceived family support. STATISTICAL ANALYSIS USED: Statistical Package for Social Sciences (SPSS) version 17.0 was used to analyze data. RESULTS: The majority of the respondents were middle-aged (61.1%) and female (59.4%). Blood pressure (BP) was controlled in 46.4% of the respondents. Most of the respondents (79.4%) had "strong" perceived family support. Strong perceived family support (odds ratio [OR] 4.778, 95% confidence interval [CI] =2.569-8.887) and female gender (OR 1.838, 95% CI = 1.177-2.869) were independent predictors of controlled BP. CONCLUSIONS: The proportion of hypertensive patients with optimal BP control is low in this practice setting. The positive association between BP control and perceived family support emphasizes the need for physicians to reflect on the available family support when managing hypertensive patients.

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