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1.
Exp Physiol ; 105(6): 989-999, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32267561

RESUMO

NEW FINDINGS: What is the central question of this study? We previously demonstrated that quercetin transiently preserved respiratory function in dystrophin-deficient mice. To gain lasting therapeutic benefits, we tested quercetin in combination with nicotinamide riboside, lisinopril and prednisolone in the D2-mdx model. What is the main finding and its importance? We demonstrated that these quercetin-based cocktails did not preserve respiratory or diaphragmatic function or reduce histological damage after 7 months of treatment starting at 4 months of age. ABSTRACT: Duchenne muscular dystrophy is characterized by the absence of dystrophin protein and causes muscle weakness and muscle injury, culminating in respiratory failure and cardiomyopathy. Quercetin transiently improved respiratory function but failed to maintain long-term therapeutic benefits in mdx mice. In this study, we combined quercetin with nicotinamide riboside (NR), lisinopril and prednisolone to assess the efficacy of quercetin-based cocktails. We hypothesized that quercetin, NR and lisinopril independently would improve respiratory function and decrease diaphragmatic injury and when combined would have additive effects. To address this hypothesis, in vivo respiratory function, in vitro diaphragmatic function and histological injury were assessed in DBA (healthy), D2-mdx (dystrophic) and D2-mdx mice treated with combinations of quercetin, NR and lisinopril from 4 to 11 months of age. Respiratory function, assessed using whole-body plethysmography, was largely similar between healthy and dystrophin-deficient mice. Diaphragm specific tension was decreased by ∼50% in dystrophic mice compared with healthy mice (P < 0.05), but fatigue resistance was similar between groups. Contractile area was decreased by ∼10% (P < 0.05) and fibrotic area increased from 3.5% in healthy diaphragms to 27% (P < 0.05) in dystrophic diaphragms. Contrary to expectations, these functional and histological parameters of disease were not offset by any intervention. These data suggest that quercetin, NR and lisinopril, independently and in combination, did not prevent diaphragmatic injury or preserve respiratory function.


Assuntos
Diafragma/fisiopatologia , Suplementos Nutricionais , Lisinopril/farmacologia , Distrofia Muscular Animal/fisiopatologia , Quercetina/farmacologia , Animais , Cardiotônicos/farmacologia , Diafragma/efeitos dos fármacos , Masculino , Camundongos Endogâmicos DBA , Camundongos Endogâmicos mdx , Contração Muscular , Debilidade Muscular
2.
JRSM Cardiovasc Dis ; 8: 2048004019879581, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31656622

RESUMO

BACKGROUND: Duchenne muscular dystrophy is a muscle wasting disease caused by dystrophin gene mutations resulting in dysfunctional dystrophin protein. Autophagy, a proteolytic process, is impaired in dystrophic skeletal muscle though little is known about the effect of dystrophin deficiency on autophagy in cardiac muscle. We hypothesized that with disease progression autophagy would become increasingly dysfunctional based upon indirect autophagic markers. METHODS: Markers of autophagy were measured by western blot in 7-week-old and 17-month-old control (C57) and dystrophic (mdx) hearts. RESULTS: Counter to our hypothesis, markers of autophagy were similar between groups. Given these surprising results, two independent experiments were conducted using 14-month-old mdx mice or 10-month-old mdx/Utrn± mice, a more severe model of Duchenne muscular dystrophy. Data from these animals suggest increased autophagosome degradation. CONCLUSION: Together these data suggest that autophagy is not impaired in the dystrophic myocardium as it is in dystrophic skeletal muscle and that disease progression and related injury is independent of autophagic dysfunction.

3.
Acta Physiol (Oxf) ; 222(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28834378

RESUMO

AIM: Duchenne muscular dystrophy is caused by the absence of functional dystrophin protein and results in a host of secondary effects. Emerging evidence suggests that dystrophic pathology includes decreased pro-autophagic signalling and suppressed autophagic flux in skeletal muscle, but the relationship between autophagy and disease progression is unknown. The purpose of this investigation was to determine the extent to which basal autophagy changes with disease progression. We hypothesized that autophagy impairment would increase with advanced disease. METHODS: To test this hypothesis, 7-week-old and 17-month-old dystrophic diaphragms were compared to each other and age-matched controls. RESULTS: Changes in protein markers of autophagy indicate impaired autophagic stimulation through AMPK, however, robust pathway activation in dystrophic muscle, independent of disease severity. Relative protein abundance of p62, an inverse correlate of autophagic degradation, was dramatically elevated with disease regardless of age. Likewise, relative protein abundance of Lamp2, a lysosome marker, was decreased twofold at 17 months of age in dystrophic muscle and was confirmed, along with mislocalization, in histological samples, implicating lysosomal dysregulation in this process. In dystrophic muscle, autophagosome-sized p62-positive foci were observed in the extracellular space. Moreover, we found that autophagosomes were released from both healthy and dystrophic diaphragms into the extracellular environment, and the occurrence of autophagosome escape was more frequent in dystrophic muscle. CONCLUSION: These findings suggest autophagic dysfunction proceeds independent of disease progression and blunted degradation of autophagosomes is due in part to decreased lysosome abundance, and contributes to autophagosomal escape to the extracellular space.


Assuntos
Autofagossomos/metabolismo , Autofagossomos/patologia , Autofagia/fisiologia , Distrofia Muscular de Duchenne/patologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/fisiopatologia
4.
N Engl J Med ; 339(12): 785-91, 1998 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-9738085

RESUMO

BACKGROUND: Herbal mixtures are popular alternatives to demonstrated therapies. PC-SPES, a commercially available combination of eight herbs, is used as a nonestrogenic treatment for cancer of the prostate. Since other herbal medicines have estrogenic effects in vitro, we tested the estrogenic activity of PC-SPES in yeast and mice and in men with prostate cancer. METHODS: We measured the estrogenic activity of PC-SPES with transcriptional-activation assays in yeast and a biologic assay in mice. We assessed the clinical activity of PC-SPES in eight patients with hormone-sensitive prostate cancer by measuring serum prostate-specific antigen and testosterone concentrations during and after treatment. RESULTS: In complementary yeast assays, a 1:200 dilution of an ethanol extract of PC-SPES had estrogenic activity similar to that of 1 nM estradiol, and in ovariectomized CD-1 mice, the herbal mixture increased uterine weights substantially. In six of six men with prostate cancer, PC-SPES decreased serum testosterone concentrations (P<0.05), and in eight of eight patients it decreased serum concentrations of prostate-specific antigen. All eight patients had breast tenderness and loss of libido, and one had venous thrombosis. High-performance liquid chromatography, gas chromatography, and mass spectrometry showed that PC-SPES contains estrogenic organic compounds that are distinct from diethylstilbestrol, estrone, and estradiol. CONCLUSIONS: PC-SPES has potent estrogenic activity. The use of this unregulated mixture of herbs may confound the results of standard or experimental therapies and may produce clinically significant adverse effects.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Receptores de Estrogênio/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/química , Mama/efeitos dos fármacos , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/química , Feminino , Humanos , Libido/efeitos dos fármacos , Masculino , Camundongos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/fisiopatologia , Saccharomyces cerevisiae/efeitos dos fármacos , Testosterona/sangue , Tromboflebite/induzido quimicamente , Útero/efeitos dos fármacos , Leveduras/efeitos dos fármacos
5.
Dig Dis Sci ; 39(10): 2127-33, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7924731

RESUMO

Gastroesophageal reflux (GER) is common among patients with asthma, and it has been speculated that high GER may exacerbate asthma in some. This study was designed to determine if suppression of acid reflux in patients with asthma would improve pulmonary function. A double-blind, placebo-controlled crossover study design was used to determine the effect of GER suppression with omeprazole (20 mg twice daily) on pulmonary function among asthmatic patients with esophagitis. Four of 15 (27%) asthma patients with GER were shown to have a > or = 20% net improvement in pulmonary function (FEV1) after treatment for six weeks with omeprazole. These results indicate that some patients with asthma and GER will have improved pulmonary function when acid GER is treated with omeprazole.


Assuntos
Asma/tratamento farmacológico , Refluxo Gastroesofágico/tratamento farmacológico , Omeprazol/uso terapêutico , Respiração/efeitos dos fármacos , Adulto , Asma/epidemiologia , Asma/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Esôfago/efeitos dos fármacos , Esôfago/fisiopatologia , Feminino , Refluxo Gastroesofágico/epidemiologia , Refluxo Gastroesofágico/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Masculino , Manometria , Pessoa de Meia-Idade , Omeprazol/farmacologia , Placebos , Estatísticas não Paramétricas
6.
Ann Allergy ; 72(5): 441-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8179231

RESUMO

Anticholinergic side effects of commonly used antihistamines are known to aggravate voiding difficulties in older men with benign prostatic hypertrophy. Newer antihistamines, such as terfenadine (Seldane), with less anticholinergic side effects may not have such an effect on voiding. We performed a randomized, double-blind, placebo-controlled, crossover study in eight normal male volunteers (phase I) and in 11 patients with documented benign prostatic hypertrophy (phase II) to study the effect of terfenadine on voiding. Subjects received either 60 mg of terfenadine or an identical placebo twice daily for 1 week each. After a 1-week washout period, they were crossed over to receive the other drug. Evaluation took place on days 0, 7, 14, and 21. Prick skin testing was performed with serial threefold dilutions of histamine to assess efficacy and degree of compliance. Uroflowmetry and urinary symptom assessment were also done. In phase I, after 1 week of terfenadine, mean skin test suppression was 83.8% compared with -0.5% with placebo (P < .01). Urinary peak flow increased 10.4% on terfenadine and 9.7% on placebo (P = NS). In phase II, the mean prick skin test suppression was 87.8% compared with 12.0% for placebo (P < .002). Urinary peak flow was decreased 0.1% from baseline on terfenadine and increased by 18.7% for placebo (P = NS). None of the subjects noted alterations in voiding symptom scores. We conclude that the commonly recommended dose of terfenadine does not significantly alter voiding characteristics in normal men or in patients with documented benign prostatic hypertrophy.


Assuntos
Terfenadina/farmacologia , Micção/efeitos dos fármacos , Micção/fisiologia , Adulto , Idoso , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Testes Cutâneos
9.
J Allergy Clin Immunol ; 69(6): 516-21, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7076992

RESUMO

A double-blind modification of the intraesophageal acid perfusion challenge (Bernstein procedure) was performed in asthmatic subjects with and without gastroesophageal reflux, nonasthmatic subjects with reflux, and normal subjects. Conventional spirometric functions and total respiratory resistance (Rrs) were measured prior to and after the infusion. There were no changes in pulmonary functions except in the asthmatic subjects who had had a positive acid challenge. The greatest changes occurred in Rrs, which increased significantly with reflux symptoms (p less than 0.01) and decreased toward baseline (p less than 0.05) when these symptoms were relieved with antacids. The response was even greater in asthmatic subjects who associated reflux symptoms with attacks of asthma. These results support previous findings that acid reflux symptoms could cause a bronchoconstrictive response in certain asthmatic patients.


Assuntos
Espasmo Brônquico/complicações , Refluxo Gastroesofágico/complicações , Resistência das Vias Respiratórias , Antiácidos/uso terapêutico , Espasmo Brônquico/diagnóstico , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/tratamento farmacológico , Azia/complicações , Humanos , Espirometria
12.
J Allergy Clin Immunol ; 57(5): 463-72, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-57131

RESUMO

The response to preseasonal immunotherapy with aqueous grass extract, timothy antigen D, or water-soluble timothy (WST) in alginate was compared in patients sensitive to grass pollen. Injections of antigen D in alginate produced little evidence of clinical or immunologic response. Treatment with aqueous grass extract or WST in alginate, on the other hand, significantly reduced the seasonal rise in grass-specific IgE. Aqueous extract therapy was also associated with a decline in leukocyte sensitivity during the pollen season, while WST treatment produced the greatest rise in hemagglutinating antibodies.


Assuntos
Antígenos , Extratos Vegetais/uso terapêutico , Poaceae/imunologia , Rinite Alérgica Sazonal/tratamento farmacológico , Alginatos/uso terapêutico , Testes de Hemaglutinação , Liberação de Histamina , Humanos , Imunoglobulina E/análise , Imunoterapia , Radioimunoensaio , Testes Cutâneos
13.
J Allergy Clin Immunol ; 55(5): 299-309, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-164490

RESUMO

Cardiovascular and metabolic responses to exercise and consecutive epinephrine infusions 24 hours apart were measured in 7 normal individuals before and following a week's administration of ephedrine sulfate. There was evidence of less beta adrenergic response to the second control epinephrine infusion compared to the first control infusion, and the depression of the rise in blood lactate was significantly different. A week of ephedrine produced more profound depression of the beta adrenergic responses to epinephrine with significant differences in the rise in blood glucose and lactate, and the pulse and blood pressure responses. Furthermore, these same responses remained significantly altered when a second epinephrine infusion was performed 36 hours following the last dose of ephedrine. The alterations in the response to epinephrine induced by ephedrine are consistent with the concept of effector cell "subsensitivity," an adaptive response to prolonged excessive stimulation.


Assuntos
Asma/imunologia , Efedrina/farmacologia , Epinefrina/farmacologia , Análise de Variância , Glicemia/análise , Brônquios/efeitos dos fármacos , Ensaios Clínicos como Assunto , AMP Cíclico/urina , Eletrocardiografia , Eosinófilos , Teste de Esforço , Ácidos Graxos não Esterificados/análise , Volume Expiratório Forçado , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lactatos/sangue , Contagem de Leucócitos , Masculino
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