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1.
J Clin Invest ; 133(18)2023 09 15.
Article in English | MEDLINE | ID: mdl-37432742

ABSTRACT

Asthma is a chronic inflammatory disease associated with episodic airway narrowing. Inhaled ß2-adrenergic receptor (ß2AR) agonists (ß2-agonists) promote - with limited efficacy - bronchodilation in asthma. All ß2-agonists are canonical orthosteric ligands that bind the same site as endogenous epinephrine. We recently isolated a ß2AR-selective positive allosteric modulator (PAM), compound-6 (Cmpd-6), which binds outside of the orthosteric site and modulates orthosteric ligand functions. With the emerging therapeutic potential of G-protein coupled receptor allosteric ligands, we investigated the impact of Cmpd-6 on ß2AR-mediated bronchoprotection. Consistent with our findings using human ß2ARs, Cmpd-6 allosterically potentiated ß2-agonist binding to guinea pig ß2ARs and downstream signaling of ß2ARs. In contrast, Cmpd-6 had no such effect on murine ß2ARs, which lack a crucial amino acid in the Cmpd-6 allosteric binding site. Importantly, Cmpd-6 enhanced ß2 agonist-mediated bronchoprotection against methacholine-induced bronchoconstriction in guinea pig lung slices, but - in line with the binding studies - not in mice. Moreover, Cmpd-6 robustly potentiated ß2 agonist-mediated bronchoprotection against allergen-induced airway constriction in lung slices obtained from a guinea pig model of allergic asthma. Cmpd-6 similarly enhanced ß2 agonist-mediated bronchoprotection against methacholine-induced bronchoconstriction in human lung slices. Our results highlight the potential of ß2AR-selective PAMs in the treatment of airway narrowing in asthma and other obstructive respiratory diseases.


Subject(s)
Asthma , Humans , Mice , Animals , Guinea Pigs , Methacholine Chloride/pharmacology , Methacholine Chloride/therapeutic use , Ligands , Asthma/drug therapy , Asthma/genetics , Asthma/complications , Lung/metabolism , Binding Sites , Receptors, Adrenergic, beta-2/genetics , Receptors, Adrenergic, beta-2/metabolism
2.
Sr Care Pharm ; 38(1): 29-40, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36751917

ABSTRACT

Objective To investigate potential reasons for unusually high incidence of negative Methacholine Challenge Tests (MCT), following standardized MCT medication-hold protocol, in older people with physician-diagnosed asthma. Design An analysis of a longitudinal observational parent study of asthma. Setting Community-dwelling participants were evaluated in an outpatient clinic and at home. Participants Screening inclusion criteria for the parent study included 60 years of age or older, physician diagnosis of asthma, and a positive response to at least one of six asthma screening questions. Participants were enrolled in the study if they also demonstrate either: (1) a postbronchodilator administration response showing an increase of at least 12% and 200 mL in forced expiratory volume or an increase of at least 12% and 200 mL in forced vital capacity, or (2) an MCT result of PC20 ≤ 16 mg/mL (indicating bronchial hyper-responsiveness, MCT positive). Exclusion criteria included diagnosis of cognitive impairment or dementia, residing in a long-term care facility, more than 20 pack/ year smoking history or a history of smoking within the previous five years, inability to perform pulmonary function testing maneuvers, and a Prognostic Index score of greater than 10. Interventions Analysis of participant data for non-medication- and medication-exposure factors for association with negative MCT results. Results Anticholinergic burden and statin use were positively associated with negative MCT. Conclusion Medications not accounted for in medication-hold protocols, and concurrently in use, may impact clinical tests and outcomes.


Subject(s)
Asthma , Polypharmacy , Humans , Aged , Methacholine Chloride/therapeutic use , Asthma/diagnosis , Asthma/drug therapy , Bronchial Provocation Tests/methods , Forced Expiratory Volume
3.
Arch. bronconeumol. (Ed. impr.) ; 59(2): 76-83, feb. 2023. ilus, graf, tab
Article in English | IBECS | ID: ibc-215578

ABSTRACT

Introduction: The role of bronchial provocation tests in the diagnosis of asthma remains to be fully explored. We aimed to evaluate methacholine and mannitol challenge testing, and explore the factors associated with this broncoprovocation response.Methods: Observational, cross-over, randomized trial evaluating adult cases with suspected asthma, naïve to treatment, with normal pre-bronchodilator spirometry, and negative bronchodilator test. Patients were randomized to start with methacholine or mannitol. The diagnosis of bronchial asthma was confirmed if there was a good functional and clinical response to one month with twice daily formoterol/budesonide 9/320. The diagnostic profile and the concordance were calculated. Factors associated with a positive provocation test were entered into a multivariate binomial logistic regression analysis, and classification trees were created for both tests.Results: The study included 108 cases (50.0% diagnosed with asthma and 51.9% cases starting with methacholine). The percentage of cases positive to methacholine and mannitol were 30.6% and 25.0% respectively. Kappa values were 0.40 (p<0.001). The diagnostic profile for methacholine was sensitivity 59.3% and specificity 98.1%, while for mannitol it was sensitivity 48.1% and specificity 98.1%. Variables associated with a positive methacholine response included sex, atopy, FEV1, FEV1/FVC and FENO, whereas they were FEV1/FVC and FENO for mannitol. A FENO value>26ppb, FEV1≤103.3% and female sex correctly classified 78.7% of methacholine responders. FENO value>26ppb was enough to correctly classify 81.5% of mannitol responders.Conclusions: Our study confirms the diagnostic profile of methacholine and mannitol challenge tests and describes the variable associated to their positivity with new proposed cutoff values. (AU)


Subject(s)
Humans , Male , Female , Young Adult , Adult , Middle Aged , Bronchodilator Agents/therapeutic use , Asthma/drug therapy , Cross-Over Studies , Bronchial Provocation Tests , Methacholine Chloride/therapeutic use , Nitric Oxide
4.
Biol Sex Differ ; 14(1): 2, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36609358

ABSTRACT

RATIONALE: Asthma is a chronic airway condition that occurs more often in women than men during reproductive years. Population studies have collectively shown that long-term use of oral contraceptives decreased the onset of asthma in women of reproductive age. In the current study, we hypothesized that steady-state levels of estrogen would reduce airway inflammation and airway hyperresponsiveness to methacholine challenge. METHODS: Ovariectomized BALB/c mice (Ovx) were implanted with subcutaneous hormone pellets (estrogen, OVX-E2) that deliver consistent levels of estrogen [68 ± 2 pg/mL], or placebo pellets (OVX-Placebo), followed by ovalbumin sensitization and challenge. In conjunction with methacholine challenge, immune phenotyping was performed to correlate inflammatory proteins and immune populations with better or worse pulmonary outcomes measured by invasive pulmonary mechanics techniques. RESULTS: Histologic analysis showed an increase in total cell infiltration and mucus staining around the airways leading to an increased inflammatory score in ovarectomized (OVX) animals with steady-state estrogen pellets (OVX-E2-OVA) as compared to other groups including female-sham operated (F-INTACT-OVA) and OVX implanted with a placebo pellet (OVX-Pl-OVA). Airway resistance (Rrs) and lung elastance (Ers) were increased in OVX-E2-OVA in comparison to F-INTACT-OVA following aerosolized intratracheal methacholine challenges. Immune phenotyping revealed that steady-state estrogen reduced CD3+ T cells, CD19+ B cells, ILC2 and eosinophils in the BAL across all experiments. While these commonly described allergic cells were reduced in the BAL, or airways, we found no changes in neutrophils, CD3+ T cells or CD19+ B cells in the remaining lung tissue. Similarly, inflammatory cytokines (IL-5 and IL-13) were also decreased in OVX-E2-OVA-treated animals in comparison to Female-INTACT-OVA mice in the BAL, but in the lung tissue IL-5, IL-13 and IL-33 were comparable in OVX-E2-OVA and F-INTACT OVA mice. ILC2 were sorted from the lungs and stimulated with exogenous IL-33. These ILC2 had reduced cytokine and chemokine expression when they were isolated from OVX-E2-OVA animals, indicating that steady-state estrogen suppresses IL-33-mediated activation of ILC2. CONCLUSIONS: Therapeutically targeting estrogen receptors may have a limiting effect on eosinophils, ILC2 and potentially other immune populations that may improve asthma symptoms in those females that experience perimenstrual worsening of asthma, with the caveat, that long-term use of estrogens or hormone receptor modulators may be detrimental to the lung microenvironment over time.


Subject(s)
Asthma , Interleukin-33 , Female , Animals , Mice , Interleukin-33/therapeutic use , Estradiol/pharmacology , Estradiol/therapeutic use , Immunity, Innate , Interleukin-13/therapeutic use , Methacholine Chloride/pharmacology , Methacholine Chloride/therapeutic use , Allergens/therapeutic use , Airway Resistance , Interleukin-5/therapeutic use , Bronchoalveolar Lavage Fluid , Lymphocytes/metabolism , Lymphocytes/pathology , Lung/metabolism , Asthma/drug therapy , Asthma/metabolism , Cytokines , Estrogens/therapeutic use
5.
Arch Bronconeumol ; 59(2): 76-83, 2023 Feb.
Article in English, Spanish | MEDLINE | ID: mdl-36371327

ABSTRACT

INTRODUCTION: The role of bronchial provocation tests in the diagnosis of asthma remains to be fully explored. We aimed to evaluate methacholine and mannitol challenge testing, and explore the factors associated with this broncoprovocation response. METHODS: Observational, cross-over, randomized trial evaluating adult cases with suspected asthma, naïve to treatment, with normal pre-bronchodilator spirometry, and negative bronchodilator test. Patients were randomized to start with methacholine or mannitol. The diagnosis of bronchial asthma was confirmed if there was a good functional and clinical response to one month with twice daily formoterol/budesonide 9/320. The diagnostic profile and the concordance were calculated. Factors associated with a positive provocation test were entered into a multivariate binomial logistic regression analysis, and classification trees were created for both tests. RESULTS: The study included 108 cases (50.0% diagnosed with asthma and 51.9% cases starting with methacholine). The percentage of cases positive to methacholine and mannitol were 30.6% and 25.0% respectively. Kappa values were 0.40 (p<0.001). The diagnostic profile for methacholine was sensitivity 59.3% and specificity 98.1%, while for mannitol it was sensitivity 48.1% and specificity 98.1%. Variables associated with a positive methacholine response included sex, atopy, FEV1, FEV1/FVC and FENO, whereas they were FEV1/FVC and FENO for mannitol. A FENO value>26ppb, FEV1≤103.3% and female sex correctly classified 78.7% of methacholine responders. FENO value>26ppb was enough to correctly classify 81.5% of mannitol responders. CONCLUSIONS: Our study confirms the diagnostic profile of methacholine and mannitol challenge tests and describes the variable associated to their positivity with new proposed cutoff values.


Subject(s)
Asthma , Bronchodilator Agents , Adult , Humans , Bronchial Provocation Tests , Methacholine Chloride/therapeutic use , Bronchodilator Agents/therapeutic use , Cross-Over Studies , Nitric Oxide , Asthma/drug therapy , Mannitol/therapeutic use
6.
J Pharmacol Exp Ther ; 381(2): 176-187, 2022 05.
Article in English | MEDLINE | ID: mdl-35153197

ABSTRACT

Mirabegron is used for treatment of storage symptoms in overactive bladder (OAB) caused by spontaneous bladder smooth muscle contractions. However, owing to limitations in available studies using human tissues, central questions are still unresolved, including mechanisms underlying improvements by mirabegron and its anticontractile effects in the detrusor. Here, we assessed concentration-dependent mirabegron effects on contractions of human detrusor tissues in frequency-response curves and concentration-response curves for different cholinergic and noncholinergic agonists. Detrusor tissues were sampled from patients undergoing radical cystectomy. Contractions were induced by electric field stimulation (EFS) and by cumulative concentrations of cholinergic agonists, endothelin-1, and the thromboxane A2 analog U46619. EFS-induced contractions were inhibited using 10 µM mirabegron, but not using 1 µM. Inhibition by 10 µM mirabegron was resistant to the ß 3-adrenergic antagonist L-748,337. Concentration-dependent contractions by carbachol were not inhibited by 1 µM or 10 µM mirabegron. Concentration-response curves for methacholine were slightly right-shifted by 10 µM, but not 1 µM mirabegron. Concentration-dependent contractions by endothelin-1 or U46619 were not changed by mirabegron. In contrast, the muscarinic antagonist tolterodine right-shifted concentration-response curves for carbachol and methacholine and inhibited EFS-induced contractions. In conclusion, inhibition of neurogenic contractions in isolated detrusor tissues by mirabegron requires concentrations highly exceeding known plasma levels during standard dosing and the known binding constant (Ki values) for ß 3-adrenoceptors. Full contractions by cholinergic agonists, endothelin-1, and U46619 are not affected by therapeutic concentrations of mirabegron. Improvements of storage symptoms are most likely not imparted by inhibition of ß 3-adrenoceptors in the bladder wall itself. SIGNIFICANCE STATEMENT: Mirabegron is used for overactive bladder (OAB) treatment, but the underlying mechanisms are unclear, and preclinical and clinical findings are controversial due to limitations in available studies. Our findings suggest that inhibition of detrusor contractions by mirabegron is limited to neurogenic contractions, which requires unphysiologic concentrations and does not involve ß 3-adrenoceptors. Mechanisms accounting for improvements of OAB by mirabegron are located outside the urinary bladder.


Subject(s)
Urinary Bladder, Overactive , 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/metabolism , 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/pharmacology , 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/therapeutic use , Acetanilides , Carbachol/pharmacology , Endothelin-1/pharmacology , Female , Humans , Male , Methacholine Chloride/metabolism , Methacholine Chloride/pharmacology , Methacholine Chloride/therapeutic use , Muscle Contraction , Muscle, Smooth , Receptors, Adrenergic/metabolism , Thiazoles , Urinary Bladder, Overactive/drug therapy , Urinary Bladder, Overactive/metabolism
7.
Mil Med ; 187(11-12): 1370-1375, 2022 10 29.
Article in English | MEDLINE | ID: mdl-34414444

ABSTRACT

BACKGROUND: Published guidelines on spirometry interpretation suggest an elevated FVC and FEV1 > 100% of predicted with an obstructive ratio may represent a physiological variant. Further evidence is needed on whether this finding indicates symptomatic airways obstruction and what additional evaluation should be done. METHODS: Participants were prospectively enrolled to undergo additional testing for a technically adequate spirometry study with an FEV1 > 90% of predicted, and FEV1/FVC below the lower limit of normal, based on 95th percentile confidence intervals. Further testing consisted of full pulmonary function testing, impulse oscillometry (IOS), post-bronchodilator testing, fractional exhaled nitric oxide (FeNO), and methacholine challenge testing (MCT). RESULTS: A total of 49 patients meeting entry criteria enrolled and completed testing. Thirty-three were considered symptomatic based on clinical indications for initial testing and 16 were considered asymptomatic. Baseline pulmonary function test values were not different between groups while IOS R5 values (% predicted) were higher in the symptomatic group (126.5 ± 0.37 vs 107.1 ± 0.31). Bronchodilator responsiveness on PFT or IOS was infrequent in both groups. There was a 29% positivity rate for MCT in the symptomatic group compared to one borderline study in asymptomatic participants. FeNO was similar for symptomatic, 26.17 ± 31.3 ppb, compared to asymptomatic, 22.8 ± 13.5 ppb (p = 0.93). The dysanapsis ratio was higher in the symptomatic (0.15 ± 0.03) compared to the asymptomatic (0.13 ± 0.02) (p < 0.05). CONCLUSION: Normal FEV1 > 90% of predicted and obstructive indices may not represent a normal physiological variant in all patients. In symptomatic patients, a positive MCT and elevated baseline IOS values were more common than in asymptomatic patients with similar PFT characteristics. These findings suggest that clinicians should still evaluate for airway hyperresponsiveness in patients with exertional dyspnea with airway obstruction and FEV1 > 90% of predicted and consider alternative diagnoses to include a normal physiologic variant if non-reactive.


Subject(s)
Asthma , Bronchodilator Agents , Humans , Bronchodilator Agents/pharmacology , Bronchodilator Agents/therapeutic use , Oscillometry , Spirometry , Asthma/diagnosis , Bronchial Provocation Tests , Methacholine Chloride/pharmacology , Methacholine Chloride/therapeutic use , Forced Expiratory Volume
9.
Pediatr Allergy Immunol ; 31(7): 767-773, 2020 10.
Article in English | MEDLINE | ID: mdl-32191368

ABSTRACT

BACKGROUND: Airway hyper-responsiveness (AHR) is a common feature in asthma. The use of AHR in predicting active asthma or the persistence of AHR in childhood is poorly understood. By analyzing longitudinal connections including different measures of AHR, lung function, and inflammation markers, we sought to identify the best available method for predicting persistence of AHR and identification of later active asthma. METHODS: We tested 105 asthmatic children aged 3-7 years with fractional exhaled nitric oxide (FeNO), impulse oscillometry (IOS), and AHR evaluated by indirect methods (hypertonic saline and exercise challenge). Ten years later, 64 children participated in the follow-up visit and were tested with FeNO, IOS, spirometry, and methacholine challenge. At both study visits, blood samples were collected, and a questionnaire was completed. RESULTS: Asthma was in remission in 66% of patients at adolescence. AHR measured by hypertonic saline challenge at preschool age was associated with asthma symptoms (OR 10.2; 95% CI 2.8, 37.3) but not with AHR estimated with methacholine challenge 10 years later. AHR measured by exercise challenge was not associated with AHR or recent asthma symptoms in adolescence. Preschool eosinophilia continued until adolescence in 87% of patients but was not associated with AHR or subjective signs of asthma 10 years later. Wheezy preschoolers with atopy had a higher risk for AHR in adolescence (OR 4.1; 95% CI 1.0, 16.2). CONCLUSION: Results from hypertonic saline challenge are associated with persistent asthma symptoms even after a decade. AHR measured by indirect methods at preschool age did not predict AHR in adolescence.


Subject(s)
Asthma/diagnosis , Respiratory Hypersensitivity/diagnosis , Adolescent , Breath Tests/methods , Bronchial Provocation Tests/methods , Child , Child, Preschool , Female , Humans , Longitudinal Studies , Male , Methacholine Chloride/therapeutic use , Nitric Oxide/therapeutic use , Prognosis , Respiratory Function Tests/methods , Respiratory Sounds/diagnosis , Spirometry/methods , Surveys and Questionnaires
11.
Int J Mol Sci ; 20(20)2019 Oct 11.
Article in English | MEDLINE | ID: mdl-31614422

ABSTRACT

Neurotensin (NT) demonstrates ambiguous activity on inflammatory processes. The present study was undertaken to test the potential anti-inflammatory activity of NT in a murine model of non-atopic asthma and to establish the contribution of NTR1 receptors. Asthma was induced in BALB/c mice by skin sensitization with dinitrofluorobenzene followed by intratracheal hapten provocation. The mice were treated intraperitoneally with NT, SR 142948 (NTR1 receptor antagonist) + NT or NaCl. Twenty-four hours after the challenge, airway responsiveness to nebulized methacholine was measured. Bronchoalveolar lavage fluid (BALF) and lungs were collected for biochemical and immunohistological analysis. NT alleviated airway hyperreactivity and reduced the number of inflammatory cells in BALF. These beneficial effects were inhibited by pretreatment with the NTR1 antagonist. Additionally, NT reduced levels of IL-13 and TNF-α in BALF and IL-17A, IL12p40, RANTES, mouse mast cell protease and malondialdehyde in lung homogenates. SR 142948 reverted only a post-NT TNF-α decrease. NT exhibited anti-inflammatory activity in the hapten-induced asthma. Reduced leukocyte accumulation and airway hyperresponsiveness indicate that this beneficial NT action is mediated through NTR1 receptors. A lack of effect by the NTR1 blockade on mast cell activation, oxidative stress marker and pro-inflammatory cytokine production suggests that other pathways can be involved, which requires further research.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Asthma/drug therapy , Haptens/adverse effects , Neurotensin/administration & dosage , Animals , Anti-Inflammatory Agents/pharmacology , Asthma/chemically induced , Asthma/immunology , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/immunology , Cytokines/metabolism , Disease Models, Animal , Gene Expression Regulation/drug effects , Humans , Injections, Intraperitoneal , Leukocytes/drug effects , Leukocytes/metabolism , Male , Methacholine Chloride/administration & dosage , Methacholine Chloride/therapeutic use , Mice , Mice, Inbred BALB C , Neurotensin/pharmacology , Pyrazoles/administration & dosage , Pyrazoles/pharmacology , Quinolines/administration & dosage , Quinolines/pharmacology
12.
J Appl Physiol (1985) ; 127(1): 31-39, 2019 07 01.
Article in English | MEDLINE | ID: mdl-31120808

ABSTRACT

Some subjects with asthma have ventilation defects that are resistant to bronchodilator therapy, and it is thought that these resistant defects may be due to ongoing inflammation or chronic airway remodeling. However, it is unclear whether regional obstruction due to bronchospasm alone persists after bronchodilator therapy. To investigate this, six young, healthy subjects, in whom inflammation and remodeling were assumed to be absent, were bronchoconstricted with a PC20 [the concentration of methacholine that elicits a 20% drop in forced expiratory volume in 1 s (FEV1)] dose of methacholine and subsequently bronchodilated with a standard dose of albuterol on three separate occasions. Specific ventilation imaging, a proton MRI technique, was used to spatially map specific ventilation across 80% of each subject's right lung in each condition. The ratio between regional specific ventilation at baseline and after intervention was used to classify areas that had constricted. After albuterol rescue from methacholine bronchoconstriction, 12% (SD 9) of the lung was classified as constricted. Of the 12% of lung units that were classified as constricted after albuterol, approximately half [7% (SD 7)] had constricted after methacholine and failed to recover, whereas half [6% (SD 4)] had remained open after methacholine but became constricted after albuterol. The incomplete regional recovery was not reflected in the subjects' FEV1 measurements, which did not decrease from baseline (P = 0.97), nor was it detectable as an increase in specific ventilation heterogeneity (P = 0.78).NEW & NOTEWORTHY In normal subjects bronchoconstricted with methacholine and subsequently treated with albuterol, not all regions of the healthy lung returned to their prebronchoconstricted specific ventilation after albuterol, despite full recovery of integrative lung indexes (forced expiratory volume in 1 s and specific ventilation heterogeneity). The regions that remained bronchoconstricted following albuterol were those with the highest specific ventilation at baseline, which suggests that they may have received the highest methacholine dose.


Subject(s)
Bronchoconstriction/drug effects , Bronchoconstrictor Agents/therapeutic use , Bronchodilator Agents/therapeutic use , Lung/drug effects , Lung/physiopathology , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/physiopathology , Administration, Inhalation , Adult , Albuterol/therapeutic use , Asthma/drug therapy , Asthma/physiopathology , Bronchial Provocation Tests/methods , Female , Forced Expiratory Volume/drug effects , Humans , Male , Methacholine Chloride/therapeutic use , Young Adult
13.
J Appl Physiol (1985) ; 126(5): 1409-1418, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30763165

ABSTRACT

Overnight analysis of tidal breathing flow volume (TBFV) loops, recorded by impedance pneumography (IP), has been successfully applied in the home monitoring of children with wheezing disorders. However, little is known on how sleep physiology modifies the relationship between TBFV profiles and wheeze. We studied such interactions in wheezing infants. Forty-three infants recruited because of recurrent lower airway symptoms were divided into three groups based on their risk of asthma: high (HR), intermediate (IR), or low (LR). Sedated patients underwent infant lung function testing including assessment of airway responsiveness to methacholine at the hospital and a full-night recording of TBFV profiles at home with IP during natural sleep. Overnight TBFV indexes were estimated from periods of higher and lower respiration variability, presumably belonging to active [rapid eye movement (REM)] and quiet [non-REM (NREM)] sleep, respectively. From 35 valid recordings, absolute time indexes showed intrasubject sleep phase differences. Peak flow relative to time and volume was lower in HR compared with LR only during REM, suggesting altered expiratory control. Indexes estimating the concavity/convexity of flow decrease during exhalation suggested limited flow during passive exhale in HR compared with IR and LR, similarly during NREM and REM. Moreover, during REM convexity was negatively correlated with maximal flow at functional residual capacity and methacholine responsiveness. We conclude that TBFV profiles determined from overnight IP recordings vary because of sleep phase and asthma risk. Physiological changes during REM, most likely decrease in respiratory muscle tone, accentuate the changes in TBFV profiles caused by airway obstruction. NEW & NOTEWORTHY Impedance pneumography was used to investigate overnight tidal breathing flow volume (TBFV) indexes and their interactions with sleep phase [rapid eye movement (REM) vs. non-REM] at home in wheezing infants. The study shows that TBFV indexes vary significantly because of sleep phase and asthma risk of the infant and that during REM the changes in TBFV indexes caused by airway obstruction are accentuated and better associated with lung function of the infant.


Subject(s)
Respiratory Sounds/physiology , Respiratory System/physiopathology , Sleep/physiology , Tidal Volume/physiology , Airway Obstruction/drug therapy , Airway Obstruction/physiopathology , Asthma/drug therapy , Asthma/physiopathology , Electric Impedance , Exhalation/drug effects , Exhalation/physiology , Female , Functional Residual Capacity/drug effects , Functional Residual Capacity/physiology , Humans , Infant , Male , Methacholine Chloride/therapeutic use , Peak Expiratory Flow Rate/drug effects , Peak Expiratory Flow Rate/physiology , Respiration/drug effects , Respiratory Function Tests/methods , Respiratory Sounds/drug effects , Respiratory System/drug effects , Sleep/drug effects , Tidal Volume/drug effects
14.
Occup Med (Lond) ; 68(8): 519-522, 2018 Nov 16.
Article in English | MEDLINE | ID: mdl-30192977

ABSTRACT

BACKGROUND: Bronchial hyper-responsiveness (BHR) is often regarded as a 'hallmark' of asthma, and bronchoprovocation testing is frequently performed to support a diagnosis of asthma. The European Respiratory Society (ERS) and American Thoracic Society (ATS) have recently updated their technical standards and guidelines for performing methacholine challenge testing (MCT), the most commonly performed clinical test of BHR. AIMS: To review the updated guidelines and discuss the various changes and their potential impact on clinicians. METHODS: We performed a systematic review of references identified using Medline and hand searches of identified articles. RESULTS: The new ERS and ATS guidelines recommend that MCT be performed using tidal breathing, not deep inspirations with breath holding, that results be reported as the PD20 (cumulative dose causing a 20% fall in forced expiratory volume in 1 s [FEV1]), rather than PC20 (concentration causing a 20% fall in FEV1), and that manufacturers of nebulizers and other delivery systems provide performance characteristics to allow calculation of PD20 values. Our preliminary survey found that the new guidelines are only slowly being adopted. CONCLUSIONS: Clinicians should be aware that recommended BHR testing methods, particularly for MCT, have changed. As a result, they should anticipate that test outcomes will increasingly be reported in terms of PD20, which will facilitate longitudinal assessment of their patients. Compliance with the new guidelines will increase the sensitivity of MCT in mild and asymptomatic asthmatics.


Subject(s)
Bronchi/physiology , Bronchial Provocation Tests/methods , Adult , Asthma/diagnosis , Asthma/physiopathology , Bronchi/physiopathology , Bronchoconstrictor Agents/therapeutic use , Female , Humans , Male , Methacholine Chloride/therapeutic use , Nebulizers and Vaporizers , Total Lung Capacity/physiology
15.
PLoS One ; 12(2): e0171721, 2017.
Article in English | MEDLINE | ID: mdl-28199353

ABSTRACT

This study investigated allergy immunotherapy potential of Lactobacillus paracasei L9 to prevent or mitigate the particulate matter 2.5 (PM2.5) enhanced pre-existing asthma in mice. Firstly, we used a mouse model of asthma (a 21-day ovalbumin (OVA) sensitization and challenge model) followed by PM2.5 exposure twice on the same day of the last challenge. PM2.5 was collected from the urban area of Beijing and underwent analysis for metals and polycyclic aromatic hydrocarbon contents. The results showed that PM2.5 exposure enhanced airway hyper-responsiveness (AHR) and lead to a mixed Th2/ IL-17 response in asthmatic mice. Secondly, the PM2.5 exposed asthmatic mice were orally administered with L9 (4×107, 4×109 CFU/mouse, day) from the day of first sensitization to the endpoint, for 20 days, to investigate the potential mitigative effect of L9 on asthma. The results showed that L9 ameliorated PM2.5 exposure enhanced AHR with an approximate 50% decrease in total airway resistance response to methacholine (48 mg/ml). L9 also prevented the exacerbated eosinophil and neutrophil infiltration in bronchoalveolar lavage fluid (BALF), and decreased the serum level of total IgE and OVA-specific IgG1 by 0.44-fold and 0.3-fold, respectively. Additionally, cytokine production showed that L9 significantly decreased T-helper cell type 2 (Th2)-related cytokines (IL-4, -5, -13) and elevated levels of Th1 related IFN-γ in BALF. L9 also reduced the level of IL-17A and increased the level of TGF-ß. Taken together, these results indicate that L9 may exert the anti-allergic benefit, possibly through rebalancing Th1/Th2 immune response and modulating IL-17 pro-inflammatory immune response. Thus, L9 is a promising candidate for preventing PM exposure enhanced pre-existing asthma.


Subject(s)
Asthma/etiology , Asthma/therapy , Hypersensitivity/therapy , Immunotherapy , Lacticaseibacillus paracasei/immunology , Probiotics/therapeutic use , Administration, Oral , Animals , Asthma/drug therapy , Asthma/immunology , Bronchoalveolar Lavage Fluid/cytology , Bronchoconstrictor Agents/pharmacology , Bronchoconstrictor Agents/therapeutic use , Disease Models, Animal , Eosinophils/cytology , Eosinophils/immunology , Female , Hypersensitivity/drug therapy , Hypersensitivity/etiology , Hypersensitivity/immunology , Lung/drug effects , Lung/immunology , Lung/pathology , Methacholine Chloride/pharmacology , Methacholine Chloride/therapeutic use , Mice , Mice, Inbred BALB C , Neutrophils/cytology , Neutrophils/immunology , Ovalbumin/immunology , Particulate Matter/toxicity , Th1 Cells/cytology , Th1 Cells/immunology , Th1 Cells/metabolism , Th2 Cells/cytology , Th2 Cells/metabolism
16.
Int J Immunopathol Pharmacol ; 29(4): 769-774, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27272161

ABSTRACT

Inhaled corticosteroids (ICS)/long-acting beta-agonists (LABA) association offers a better asthma control than a higher steroid dose with short-acting beta-agonists as needed. In this study, we evaluated the effect of the association on bronchial hyperreactivity (BHR) and peak expiratory flow (PEF) variability, as such parameters are positively correlated with increased asthma morbidity and exacerbations. Thirty-six adult patients with mild persistent asthma were enrolled. After a 7-day run-in, they were randomly assigned to three therapy regimens for 6 weeks: Group 1, fluticasone 125 µg + formoterol 5 µg in the same device; Group 2, fluticasone 125 µg + formoterol 12 µg as needed; Group 3, fluticasone 250 µg + formoterol 12 µg as needed. We evaluated changes induced in weekly PEF variability (measured during the entire study and 4 weeks of follow-up) and pre- and post-study PD20 methacholine (MCH). Weekly PEF variability decreased in all groups during treatment with the greatest reduction in Group 1, followed by Group 3, and finally Group 2. During the follow-up, no significant changes were detected in Group 1, whereas a trend towards an increased variability was found in Groups 2 and 3. Post-treatment PD20 MCH was significantly higher versus the pre-treatment. The increase observed in Group 1 was significantly higher compared to Groups 2 and 3 and that observed in Group 3 in respect to Group 2. The study proves that both BHR and PEF variability are influenced by ICS. This effect was greater with fluticasone/formoterol association compared to fluticasone alone with formoterol as needed even at higher steroid dose.


Subject(s)
Bronchodilator Agents/therapeutic use , Fluticasone/therapeutic use , Formoterol Fumarate/therapeutic use , Methacholine Chloride/therapeutic use , Peak Expiratory Flow Rate/drug effects , Administration, Inhalation , Adrenal Cortex Hormones/therapeutic use , Adrenergic beta-2 Receptor Agonists/therapeutic use , Adult , Asthma/drug therapy , Bronchoconstrictor Agents/therapeutic use , Female , Humans , Male
18.
Allergol. immunopatol ; 44(2): 106-112, mar.-abr. 2016. graf, tab
Article in English | IBECS | ID: ibc-150656

ABSTRACT

BACKGROUND: Ciclesonide (CIC) is an effective inhaled corticosteroid for treating asthmatic children. However, its effect on airway inflammation assessed by the fraction of exhaled nitric oxide (FENO) in children with persistent asthma is virtually unknown. We aimed to assess the effect of once-daily generic CIC, 80 or 160 μg, on FENO, lung function, asthma control and bronchial hyperresponsiveness, in atopic children with persistent asthma. METHODS: This was a 12-week, randomised, double-blind, parallel-group study. Sixty children with mild-to-moderate persistent asthma were recruited. Changes in FENO, asthma control score, lung function (FEV1) and bronchial hyperresponsiveness to methacholine (BHR) were used to assess the effects of both CIC doses. Non-normally distributed variables were log-transformed to approximate normality, and parametric tests were used for comparisons within and between groups at baseline and after 12 weeks of treatment. RESULTS: In the CIC 80 μg group, FENO decreased from 45.0 ppb (95% CI 37.8-53.7) to 32.7 ppb (95% CI 21.0-47.3) at the end of study (P = 0.021), whereas in the CIC 160 μg group, FENO decreased from 47.3 ppb (95% CI 40.4-55.3) to 30.5 ppb (95% CI 24.1-38.7) (P < 0.001). The difference between groups in FENO at the end of study was not significant (P = 0.693). There was a significant improvement of asthma control with both CIC doses but there was no significant change in BHR or FEV1 in either group. CONCLUSION: Once-daily generic ciclesonide (80 μg or 160 μg), for 12 weeks, is effective to improve airway inflammation and asthma control in atopic children with persistent asthma


No disponible


Subject(s)
Humans , Male , Female , Child , Adolescent , Asthma/diagnosis , Asthma/drug therapy , Asthma/prevention & control , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/therapeutic use , Glucocorticoids/therapeutic use , Glucocorticoids/administration & dosage , Nitric Oxide/therapeutic use , Epidemiological Monitoring/trends , Bronchial Hyperreactivity/prevention & control , Bronchial Hyperreactivity/drug therapy , Methacholine Chloride/therapeutic use , Spirometry , Recurrence , Lung/physiology , Chile/epidemiology
19.
Arerugi ; 65(1): 32-40, 2016 Feb.
Article in Japanese | MEDLINE | ID: mdl-26923652

ABSTRACT

BACKGROUND: In abroad, Methacholine Chloride (Provocholine®) is used to meet the indications of the diagnosis of bronchial airway hyperreactivity in subjects who do not have clinically apparent asthma. We examined efficacy, safety and pharmacokinetics of Methacholine Chloride (name of study drug: SK-1211) in order to get approved for the airway hyperresponsiveness test in Japan. METHODS: Fifteen adult healthy volunteers, fifteen adult patients with asthma and ten pediatric patients with asthma were enrolled in this study. The airway hyperresponsiveness test with SK-1211 was conducted in accordance with Japanese Society of Allergology Standard Method. RESULTS: When the threshold value of PC20 was 8 mg/mL, the sensitivity of adult patients with asthma was 66.7% (10/15 subjects) and the specificity of adult healthy volunteers was 86.7% (13/15 subjects). The sensitivity of pediatric patients with asthma was 70.0% (7/10 subjects). Not all subjects experienced some adverse reactions during inhalation of SK-1211, all of which were mild in severity and resolved soon with inhalation of a bronchodilator. There were no serious adverse reactions reported. CONCLUSION: The airway hyperresponsiveness test with SK-1211 was no specific concern with safety and useful in the diagnosis of bronchial airway hyperresponsiveness.


Subject(s)
Asthma/drug therapy , Methacholine Chloride/therapeutic use , Adolescent , Adult , Bronchial Provocation Tests , Bronchodilator Agents , Child , Female , Humans , Male , Methacholine Chloride/adverse effects , Young Adult
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