RESUMO
Group 3 innate lymphoid cells (ILC3s) critically regulate host-microbe interactions in the gastrointestinal tract, but their role in the airway remains poorly understood. Here, we demonstrate that lymphoid-tissue-inducer (LTi)-like ILC3s are enriched in the lung-draining lymph nodes of healthy mice and humans. These ILC3s abundantly express major histocompatibility complex class II (MHC class II) and functionally restrict the expansion of allergen-specific CD4+ T cells upon experimental airway challenge. In a mouse model of house-dust-mite-induced allergic airway inflammation, MHC class II+ ILC3s limit T helper type 2 (Th2) cell responses, eosinophilia, and airway hyperresponsiveness. Furthermore, MHC class II+ ILC3s limit a concomitant Th17 cell response and airway neutrophilia. This exacerbated Th17 cell response requires exposure of the lung to microbial stimuli, which can be found associated with house dust mites. These findings demonstrate a critical role for antigen-presenting ILC3s in orchestrating immune tolerance in the airway by restricting pro-inflammatory T cell responses to both allergens and microbes.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Imunidade Inata/imunologia , Linfócitos/fisiologia , Respiração/imunologia , Imunidade Adaptativa/imunologia , Alérgenos/imunologia , Animais , Asma/imunologia , Linfócitos T CD4-Positivos/imunologia , Citocinas/metabolismo , Feminino , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Inflamação/patologia , Pulmão/imunologia , Linfonodos/imunologia , Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pyroglyphidae/imunologia , Hipersensibilidade Respiratória/imunologia , Células Th17/metabolismo , Células Th2/metabolismoRESUMO
Rett syndrome is a neurodevelopmental disorder caused by mutations of the methyl-CpG binding protein 2 gene. Abnormal physiological functions of glial cells contribute to pathogenesis of Rett syndrome. Semaphorin 4D (SEMA4D) regulates processes central to neuroinflammation and neurodegeneration including cytoskeletal structures required for process extension, communication, and migration of glial cells. Blocking SEMA4D-induced gliosis may preserve normal glial and neuronal function and rescue neurological dysfunction in Rett syndrome. We evaluated the pre-clinical therapeutic efficacy of an anti-SEMA4D monoclonal antibody in the Rett syndrome Mecp2T158A transgenic mouse model and investigated the contribution of glial cells as a proposed mechanism of action in treated mice and in primary glial cultures isolated from Mecp2T158A/y mutant mice. SEMA4D is upregulated in neurons while glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1-positive cells are upregulated in Mecp2T158A/y mice. Anti-SEMA4D treatment ameliorates Rett syndrome-specific symptoms and improves behavioural functions in both pre-symptomatic and symptomatic cohorts of hemizygous Mecp2T158A/y male mice. Anti-SEMA4D also reduces astrocyte and microglia activation in vivo. In vitro experiments demonstrate an abnormal cytoskeletal structure in mutant astrocytes in the presence of SEMA4D, while anti-SEMA4D antibody treatment blocks SEMA4D-Plexin B1 signaling and mitigates these abnormalities. These results suggest that anti-SEMA4D immunotherapy may be an effective treatment option to alleviate symptoms and improve cognitive and motor function in Rett syndrome.
Assuntos
Síndrome de Rett/metabolismo , Síndrome de Rett/fisiopatologia , Semaforinas/metabolismo , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Cognição/fisiologia , Modelos Animais de Doenças , Imunoterapia , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Destreza Motora/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Receptores de Superfície Celular/metabolismo , Respiração/imunologia , Síndrome de Rett/genética , Semaforinas/genética , Semaforinas/imunologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Positron emission tomography (PET) combined with X-ray computed tomography (CT) is an important molecular imaging platform that is required for accurate diagnosis and clinical staging of a variety of diseases. The advantage of PET imaging is the ability to visualize and quantify a myriad of biological processes in vivo with high sensitivity and accuracy. However, there are multiple factors that determine image quality and quantitative accuracy of PET images. One of the foremost factors influencing image quality in PET imaging of the thorax and upper abdomen is respiratory motion, resulting in respiration-induced motion blurring of anatomical structures. Correction of these artefacts is required for providing optimal image quality and quantitative accuracy of PET images. Several respiratory gating techniques have been developed, typically relying on acquisition of a respiratory signal simultaneously with PET data. Based on the respiratory signal acquired, PET data is selected for reconstruction of a motion-free image. Although these methods have been shown to effectively remove respiratory motion artefacts from PET images, the performance is dependent on the quality of the respiratory signal being acquired. In this study, the use of an amplitude-based optimal respiratory gating (ORG) algorithm is discussed. In contrast to many other respiratory gating algorithms, ORG permits the user to have control over image quality versus the amount of rejected motion in the reconstructed PET images. This is achieved by calculating an optimal amplitude range based on the acquired surrogate signal and a user-specified duty cycle (the percentage of PET data used for image reconstruction). The optimal amplitude range is defined as the smallest amplitude range still containing the amount of PET data required for image reconstruction. It was shown that ORG results in effective removal of respiration-induced image blurring in PET imaging of the thorax and upper abdomen, resulting in improved image quality and quantitative accuracy.
Assuntos
Algoritmos , Fluordesoxiglucose F18/uso terapêutico , Tomografia por Emissão de Pósitrons/métodos , Respiração/imunologia , Artefatos , HumanosRESUMO
The neural control system underlying breathing is sexually dimorphic with males being more vulnerable to dysfunction. Microglia also display sex differences, and their role in the architecture of brainstem respiratory rhythm circuitry and modulation of cervical spinal cord respiratory plasticity is becoming better appreciated. To further understand the molecular underpinnings of these sex differences, we performed RNA sequencing of immunomagnetically isolated microglia from brainstem and cervical spinal cord of adult male and female rats. We used various bioinformatics tools (Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, Reactome, STRING, MAGICTRICKS) to functionally categorize identified gene sets, as well as to pinpoint common transcriptional gene drivers that may be responsible for the observed transcriptomic differences. We found few sex differences in the microglial transcriptomes derived from the brainstem, but several hundred genes were differentially expressed by sex in cervical spinal microglia. Comparing brainstem and spinal microglia within and between sexes, we found that the major factor guiding transcriptomic differences was central nervous system (CNS) location rather than sex. We further identified key transcriptional drivers that may be responsible for the transcriptomic differences observed between sexes and CNS regions; enhancer of zeste homolog 2 emerged as the predominant driver of the differentially downregulated genes. We suggest that functional gene alterations identified in metabolism, transcription, and intercellular communication underlie critical microglial heterogeneity and sex differences in CNS regions that contribute to respiratory disorders categorized by dysfunction in neural control. These data will also serve as an important resource data base to advance our understanding of innate immune cell contributions to sex differences and the field of respiratory neural control. SIGNIFICANCE STATEMENT: The contributions of central nervous system (CNS) innate immune cells to sexually dimorphic differences in the neural circuitry controlling breathing are poorly understood. We identify key transcriptomic differences, and their transcriptional drivers, in microglia derived from the brainstem and the C3-C6 cervical spinal cord of healthy adult male and female rats. Gene alterations identified in metabolism, gene transcription, and intercellular communication likely underlie critical microglial heterogeneity and sex differences in these key CNS regions that contribute to the neural control of breathing.
Assuntos
Tronco Encefálico/metabolismo , Medula Cervical/metabolismo , Microglia/metabolismo , Respiração/genética , Caracteres Sexuais , Transcriptoma/genética , Animais , Tronco Encefálico/imunologia , Medula Cervical/imunologia , Feminino , Imunidade Inata/genética , Masculino , Microglia/imunologia , Ratos , Respiração/imunologiaRESUMO
Unrestrained barometric plethysmography (UBP) is a method for quantifying the pattern of breathing in mice, where breathing frequency, tidal volume, and minute ventilation are routinely reported. Moreover, information can be collected regarding the neural output of breathing, including the existence of central apneas and augmented breaths. An important consideration for UBP is obtaining a breathing segment with a minimal impact of anxious or active behaviors, to elucidate the response to breathing challenges. Here, we present a protocol that allows for short, quiet baselines to be obtained in aged mice, comparable to waiting for longer bouts of quiet breathing. The use of shorter time segments is valuable, as some strains of mice may be increasingly excitable or anxious, and longer periods of quiet breathing may not be achieved within a reasonable timeframe. We placed 22 month-old mice in a UBP chamber and compared four 15 s quiet breathing segments between minutes 60-120 to a longer 10 min quiet breathing period that took 2-3 h to acquire. We also obtained counts of central apneas and augmented breaths prior to the quiet breathing segments, following a 30 min familiarization period. We show that 10 min of quiet breathing is comparable to using a much shorter 15 s duration. Additionally, the time leading up to these 15 s quiet breathing segments can be used to gather data regarding apneas of central origin. This protocol allows investigators to collect pattern-of-breathing data in a set amount of time and makes quiet baseline measures feasible for mice that may exhibit increased amounts of excitable behavior. The UBP methodology itself provides a useful and noninvasive way to collect pattern-of-breathing data and allows for mice to be tested over several time points.
Assuntos
Pletismografia/métodos , Respiração/imunologia , Animais , Masculino , CamundongosRESUMO
Pulmonary respiration inevitably exposes the mucosal surface of the lung to potentially noxious stimuli, including pathogens, allergens, and particulates, each of which can trigger pulmonary damage and inflammation. As inflammation resolves, B and T lymphocytes often aggregate around large bronchi to form inducible Bronchus-Associated Lymphoid Tissue (iBALT). iBALT formation can be initiated by a diverse array of molecular pathways that converge on the activation and differentiation of chemokine-expressing stromal cells that serve as the scaffolding for iBALT and facilitate the recruitment, retention, and organization of leukocytes. Like conventional lymphoid organs, iBALT recruits naïve lymphocytes from the blood, exposes them to local antigens, in this case from the airways, and supports their activation and differentiation into effector cells. The activity of iBALT is demonstrably beneficial for the clearance of respiratory pathogens; however, it is less clear whether it dampens or exacerbates inflammatory responses to non-infectious agents. Here, we review the evidence regarding the role of iBALT in pulmonary immunity and propose that the final outcome depends on the context of the disease.
Assuntos
Brônquios/imunologia , Imunidade nas Mucosas/imunologia , Respiração/imunologia , Humanos , Linfócitos/imunologiaRESUMO
Neonatal respiratory impairment during infection is common, yet its effects on respiratory neural circuitry are not fully understood. We hypothesized that the timing and severity of systemic inflammation is positively correlated with impairment in neonatal respiratory activity. To test this, we evaluated time- and dose-dependent impairment of in vitro fictive respiratory activity. Systemic inflammation (induced by lipopolysaccharide, LPS, 5 mg/kg, i.p.) impaired burst amplitude during the early (1 h) inflammatory response. The greatest impairment in respiratory activity (decreased amplitude, frequency, and increased rhythm disturbances) occurred during the peak (3 h) inflammatory response in brainstem-spinal cord preparations. Surprisingly, isolated medullary respiratory circuitry within rhythmic slices showed decreased baseline frequency and delayed onset of rhythm only after higher systemic inflammation (LPS 10 mg/kg) early in the inflammatory response (1 h), with no impairments at the peak inflammatory response (3 h). Thus, different components of neonatal respiratory circuitry have differential temporal and dose sensitivities to systemic inflammation, creating multiple windows of vulnerability for neonates after systemic inflammation.
Assuntos
Inflamação , Lipopolissacarídeos/farmacologia , Bulbo , Atividade Motora/fisiologia , Periodicidade , Respiração , Medula Espinal , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Expressão Gênica/fisiologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/fisiopatologia , Masculino , Bulbo/imunologia , Bulbo/metabolismo , Bulbo/fisiopatologia , Ratos Sprague-Dawley , Respiração/imunologia , Medula Espinal/imunologia , Medula Espinal/metabolismo , Medula Espinal/fisiopatologiaRESUMO
OBJECTIVE: To determine whether transcranial direct current stimulation augments the analgesic effect of breathing-controlled electrical stimulation in patients with spinal cord injury who have chronic neuropathic pain. DESIGN: Sham-controlled, single-blinded, single-centre, cross-over study of 12 participants with incomplete spinal cord injury. The treatment protocol included a 20-min transcranial direct current stimulation (sham or active), followed by a 20-min breathing-controlled electrical stimulation to the median nerve on the dominant side. The treatment session with sham or control transcranial direct current stimulation was given on different days in a randomized order. Visual analogue scale was used to assess neuropathic pain at baseline, 10 min after transcranial direct current stimulation, and 10 min after breathing-controlled electrical stimulation. RESULTS: Participants were blinded to the status of transcranial direct current stimulation. Out of the 12 participants, 10 completed sessions of both sham and active transcranial direct current stimulation, while the other 2 completed only active transcranial direct current stimulation and breathing-controlled electrical stimulation treatment. Out of the 12 participants, 7 showed analgesic effects after active transcranial direct current stimulation, while sham transcranial direct current stimulation produced some analgesic effects in 4 out of 10 participants. At the group level, there was no difference between active and sham transcranial direct current stimulation treatment. All except one participant responded positively to breathing-controlled electrical stimulation in all sessions. Visual analogue scale score for pain decreased significantly after breathing-controlled electrical stimulation combined with either active transcranial direct current stimulation or sham transcranial direct current stimulation treatment. CONCLUSION: The immediate analgesic effect of breathing-controlled electrical stimulation was confirmed. However, this effect was not augmented after one session of transcranial direct current stimulation treatment.
Assuntos
Estimulação Elétrica/métodos , Neuralgia/terapia , Medição da Dor/métodos , Respiração/imunologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Adolescente , Adulto , Idoso , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The complexity of respiratory dynamics is decreased, in association with disease severity, in patients with asthma. However, the pathophysiological basis of decreased complexity of breathing pattern in asthma is not clear. In the present study, we investigated the effect of airway remodeling and hyperresponsiveness induced by repeated bronchoconstriction (using methacholine) on breathing pattern in rats with or without allergen-induced sensitization. Entropy analysis of respiratory variability showed decreased irregularity (less complexity) of respiratory rhythm in this rat model of asthma. Airway remodeling and hyperresponsiveness induced by repeated bronchoconstriction also led to increased regularity of respiratory dynamics in sensitized rats. However, these airway alterations had no significant effect on the complexity of breathing pattern in non-sensitized rats. Our results indicate that mechanical respiratory alterations cannot per se attenuate the complexity of respiratory dynamics, unless there is an underlying inflammation. We suggest further studies on underlying mechanisms of breathing variability with focus on respiratory control alterations due to airway inflammation.
Assuntos
Remodelação das Vias Aéreas , Asma/fisiopatologia , Respiração , Hipersensibilidade Respiratória/fisiopatologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Remodelação das Vias Aéreas/fisiologia , Animais , Asma/patologia , Broncoconstritores/farmacologia , Modelos Animais de Doenças , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Cloreto de Metacolina/farmacologia , Distribuição Aleatória , Ratos Sprague-Dawley , Respiração/efeitos dos fármacos , Respiração/imunologia , Hipersensibilidade Respiratória/patologia , Organismos Livres de Patógenos EspecíficosRESUMO
Lethal influenza A (H5N1) induces respiratory failure in humans. Although it also causes death at 7 days postinfection (dpi) in mice, the development of the respiratory failure and the viral impact on pre-Botzinger complex (PBC) neurons expressing neurokinin 1 receptor (NK1R), which is the respiratory rhythm generator, have not been explored. Body temperature, weight, ventilation, and arterial blood pH and gases were measured at 0, 2, 4, and 6 dpi in control, lethal HK483, and nonlethal HK486 viral-infected mice. Immunoreactivities (IR) of PBC NK1R, H5N1 viral nucleoprotein (NP), and active caspase-3 (CASP3; a marker for apoptosis) were detected at 6 dpi. HK483, but not HK486, mice showed the following abnormalities: 1) gradual body weight loss and hypothermia; 2) tachypnea at 2-4 dpi and ataxic breathing with long-lasting apneas and hypercapnic hypoxemia at 6 dpi; and 3) viral replication in PBC NK1R neurons with NK1R-IR reduced by 75% and CASP3-IR colabeled at 6 dpi. Lethal H5N1 viral infection causes tachypnea at the early stage and ataxic breathing and apneas (hypercapnic hypoxemia) leading to death at the late stage. Its replication in the PBC induces apoptosis of local NK1R neurons, contributing to ataxic breathing and respiratory failure.
Assuntos
Apoptose/fisiologia , Virus da Influenza A Subtipo H5N1 , Neurônios/virologia , Infecções por Orthomyxoviridae/virologia , Receptores da Neurocinina-1/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Hipercapnia/virologia , Influenza Humana/virologia , Camundongos Endogâmicos BALB C , Respiração/imunologiaRESUMO
PURPOSE: The purpose of this study was to evaluate the impact of the active breathing control (ABC) technique on IMN coverage and organs at risk in patients planned for postmastectomy radiation therapy (PMRT), with the inclusion of the internal mammary lymph nodes (IMNs). The effect of body mass index (BMI) on recorded dosimetric parameters was examined in the same patient cohort. METHODS AND MATERIALS: Fifty left-sided postmastectomy patients with breast cancer who underwent free-breathing (FB) and ABC-Elekta CT simulation scans were selected at random from an institutional breast cancer database between 2008 and 2014. The ABC plans were directly compared with FB plans from the same patient. RESULTS: The IMN planning target volume coverage met dosimetric criteria for coverage of receiving more than 90% of the prescribed dose (V90) >90%, although it decreased with ABC compared with FB (94.5% vs 98%, P < .001). Overall, ABC significantly reduced doses to all measured heart and left anterior descending coronary artery parameters, ipsilateral lung V20, and mean lung dose compared with FB (P < .001). There was no difference seen between the ABC and FB plans with respect to the dose to contralateral lung or contralateral breast. There was no correlation identified between BMI and any of the dosimetric parameters recorded from the ABC and FB plans. CONCLUSIONS: Our results suggest that ABC reduces IMN coverage in left-sided breast cancer patients planned for PMRT; however, dosimetric criteria for IMN coverage were still met, suggesting that this is not likely to be clinically significant. ABC led to significant sparing of organs at risk compared with FB conditions and was not affected by BMI. Collectively, the results support the use of ABC for breast cancer patients undergoing left-sided PMRT requiring regional nodal irradiation that includes the IMNs. Further prospective clinical studies are required to determine the impact of these results on late normal tissue effects.
Assuntos
Neoplasias da Mama/radioterapia , Suspensão da Respiração/imunologia , Respiração/imunologia , Adulto , Índice de Massa Corporal , Neoplasias da Mama/patologia , Feminino , Humanos , Linfonodos/patologia , Dosagem Radioterapêutica , Adulto JovemRESUMO
BACKGROUND AND OBJECTIVE: While chronic inflammation of the airway wall and the failure of deep inspiration (DI) to produce bronchodilation are both common to asthma, whether pro-inflammatory cytokines modulate the airway smooth muscle response to strain during DI is unknown. The primary aim of the study was to determine how an inflammatory environment (simulated by the use of pro-inflammatory cytokines) alters the bronchodilatory response to DI. METHODS: We used whole porcine bronchial segments in vitro that were cultured in medium containing tumour necrosis factor and interleukin-1ß for 2 days. A custom-built servo-controlled syringe pump and pressure transducer was used to measure airway narrowing and to simulate tidal breathing with intermittent DI manoeuvres. RESULTS: Culture with tumour necrosis factor and interleukin-1ß increased airway narrowing to acetylcholine but did not affect the bronchodilatory response to DI. CONCLUSION: The failure of DI to produce bronchodilation in patients with asthma may not necessarily involve a direct effect of pro-inflammatory cytokines on airway tissue. A relationship between inflammation and airway hyper-responsiveness is supported, however, regulated by separate disease processes than those which attenuate or abolish the bronchodilatory response to DI in patients with asthma.
Assuntos
Asma , Brônquios , Interleucina-1beta/metabolismo , Respiração/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Asma/metabolismo , Asma/fisiopatologia , Brônquios/metabolismo , Brônquios/fisiopatologia , Inflamação/metabolismo , Músculo Liso/metabolismo , Músculo Liso/fisiopatologia , Fenômenos Fisiológicos Respiratórios , SuínosRESUMO
Dairy calves in the western United States are commonly raised individually in wooden hutches with a space allowance of 1.23m(2)/calf. Recent legislative initiatives in California and across the United States were passed regarding concern over space allowance for farm animals. The objective of this study was to determine if rearing male Holstein calves in wooden hutches modified to increase space allowance would influence measures of performance, lying time per day, health, and respiratory immunocompetence. At 4d of age, 60 calves were randomly assigned to 1 of 3housing treatments: (1) conventional housing (CONV; 1.23m(2)/calf), (2) 1.5 × CONV (MOD; 1.85m(2)/calf), or (3) 3 × CONV (MAX; 3.71m(2)/calf). Intakes of milk and solid feed were recorded daily and body weight was measured at 0, 3, 6, 10, and 12 wk of age. For the first 3 wk of the trial, calves were scored daily for fecal consistency, hydration, and hide cleanliness. In addition, calves were scored for respiratory health (i.e., nasal and eye discharge, ear position) until 7 wk of age. The total lying duration per day was recorded using data loggers at 3, 6, and 10 wk of age. Eight clinically healthy calves from each treatment were sensitized with subcutaneous ovalbumin (OVA) and then challenged with aerosolized OVA to assess calf respiratory immunity at 11 wk of age. Bronchoalveolar lavage fluid (BALF) was collected 4d after the OVA challenge and analyzed for leukocyte differentials and OVA-specific IgG, IgG1, IgA, and IgE. Calf average daily gain and body weight were positively associated with space allowance at approximately 3 wk before weaning and throughout postweaning, respectively. A greater space allowance decreased lying time after 46d. Space allowance did not influence fecal consistency, but there was a tendency for MAX calves to take 1d longer to recover from loose feces than MOD calves. The MAX calves had the fewest (%) observations with feces on their body compared with CONV or MOD. At 3 wk of age, peripheral eosinophil concentrations decreased with increased space allowance. However, observations (%) of eye discharge increased with greater space allowance. Among calves challenged with OVA, MOD calves had the least BALF OVA-IgE, and the percent of BALF eosinophils decreased with increased space allowance. Increased space allowance for calves raised in wooden hutches may improve some measures of calf performance, health, and respiratory immunocompetence.
Assuntos
Criação de Animais Domésticos/instrumentação , Bovinos/fisiologia , Abrigo para Animais , Atividade Motora , Respiração/imunologia , Animais , California , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Masculino , Distribuição AleatóriaRESUMO
Altered bioenergetics with increased mitochondrial reactive oxygen species production and degradation of epithelial function are key aspects of pathogenesis in asthma and chronic obstructive pulmonary disease (COPD). This motif is not unique to obstructive airway disease, reported in related airway diseases such as bronchopulmonary dysplasia and parenchymal diseases such as pulmonary fibrosis. Similarly, mitochondrial dysfunction in vascular endothelium or skeletal muscles contributes to the development of pulmonary hypertension and systemic manifestations of lung disease. In experimental models of COPD or asthma, the use of mitochondria-targeted antioxidants, such as MitoQ, has substantially improved mitochondrial health and restored respiratory function. Modulation of noncoding RNA or protein regulators of mitochondrial biogenesis, dynamics, or degradation has been found to be effective in models of fibrosis, emphysema, asthma, and pulmonary hypertension. Transfer of healthy mitochondria to epithelial cells has been associated with remarkable therapeutic efficacy in models of acute lung injury and asthma. Together, these form a 3R model--repair, reprogramming, and replacement--for mitochondria-targeted therapies in lung disease. This review highlights the key role of mitochondrial function in lung health and disease, with a focus on asthma and COPD, and provides an overview of mitochondria-targeted strategies for rejuvenating cellular respiration and optimizing respiratory function in lung diseases.
Assuntos
Asma/metabolismo , Respiração Celular/fisiologia , Pulmão/metabolismo , Mitocôndrias/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Animais , Asma/tratamento farmacológico , Asma/patologia , Humanos , Pulmão/patologia , Mitocôndrias/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Respiração/efeitos dos fármacos , Respiração/imunologiaRESUMO
Our objective was to assess whether obstructive sleep apnoea (OSA) patients were characterised by a reduced central CO2 controller gain (CG) and an enhanced plant gain (PG). We matched three groups of women (n=10 per group) enrolled in a previous study (Essalhi et al., J. Asthma. 50: 565-572, 2013): obese women with a respiratory disturbance index (RDI)≥15/h and with a RDI<15, and lean women without OSA (RDI<5). Tidal ventilation recordings during wakefulness with end-tidal PCO2 monitoring allowed the assessment of loop gain (LG) and its components (PG and CG). LG were similar for the three groups (p=0.844) while both PG and CG depicted significant differences (p=0.046 and p=0.011, respectively). Obese women with OSA were characterised by an increased PG and a reduced CG as compared to obese women without OSA. A negative relationship between CG and RDI (rho=-0.46, p=0.008) was evidenced. In conclusion, OSA in women is associated with a reduced central CO2 controller gain and an enhanced plant gain.
Assuntos
Dióxido de Carbono/sangue , Obesidade/complicações , Oxigênio/sangue , Respiração/imunologia , Apneia Obstrutiva do Sono/complicações , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Testes de Função Respiratória , Volume de Ventilação Pulmonar/fisiologiaRESUMO
The purpose of this study was to examine gender difference in human response to temperature step changes. A total of three step-change conditions (S5: 32 °C-37 °C-32 °C, S11: 26 °C-37 °C-26 °C, and S15: 22 °C-37 °C-22 °C) were designed and a laboratory experiment with 12 males and 12 females was performed. Results of this study support our hypothesis that females differ from males in human response to sudden temperature changes from the perspectives of psychology, physiology and biomarkers. Females are more prone to show thermal dissatisfaction to cool environments while males are more likely to feel thermal discomfort in warm environments. It is logical that men have a stronger thermoregulation ability than women as male skin temperature change amplitude is smaller while the time to be stable for skin temperature is shorter than that of females after both up-steps and down-steps. In S15, males witnessed a more intensive decrease in RMSSD while females underwent a remarkable instant reduce in oral temperatures after the up-step. Marginal significance was observed in male IL-6 before and after the up-step in S15 while female IL-6 prominently increased after the down-step in S15.
Assuntos
Regulação da Temperatura Corporal/fisiologia , Caracteres Sexuais , Temperatura Cutânea/fisiologia , Sensação Térmica/fisiologia , Análise de Variância , Eletrocardiografia , Fadiga/fisiopatologia , Feminino , Proteínas de Choque Térmico HSP72/metabolismo , Frequência Cardíaca/fisiologia , Humanos , Interleucina-6/metabolismo , Masculino , Percepção/fisiologia , Resistência Física/fisiologia , Psicometria , Respiração/imunologia , Temperatura , Fatores de Tempo , Adulto JovemRESUMO
This study aims to assess regional ventilation, nonlinearity, and hysteresis of human lungs during dynamic breathing via image registration of four-dimensional computed tomography (4D-CT) scans. Six healthy adult humans were studied by spiral multidetector-row CT during controlled tidal breathing as well as during total lung capacity and functional residual capacity breath holds. Static images were utilized to contrast static vs. dynamic (deep vs. tidal) breathing. A rolling-seal piston system was employed to maintain consistent tidal breathing during 4D-CT spiral image acquisition, providing required between-breath consistency for physiologically meaningful reconstructed respiratory motion. Registration-derived variables including local air volume and anisotropic deformation index (ADI, an indicator of preferential deformation in response to local force) were employed to assess regional ventilation and lung deformation. Lobar distributions of air volume change during tidal breathing were correlated with those of deep breathing (R(2) ≈ 0.84). Small discrepancies between tidal and deep breathing were shown to be likely due to different distributions of air volume change in the left and the right lungs. We also demonstrated an asymmetric characteristic of flow rate between inhalation and exhalation. With ADI, we were able to quantify nonlinearity and hysteresis of lung deformation that can only be captured in dynamic images. Nonlinearity quantified by ADI is greater during inhalation, and it is stronger in the lower lobes (P < 0.05). Lung hysteresis estimated by the difference of ADI between inhalation and exhalation is more significant in the right lungs than that in the left lungs.
Assuntos
Tomografia Computadorizada Quadridimensional/métodos , Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Ventilação Pulmonar/fisiologia , Respiração/imunologia , Capacidade Residual Funcional/fisiologia , Humanos , Tamanho do Órgão/fisiologia , Volume de Ventilação Pulmonar/fisiologiaRESUMO
The locomotor-respiratory coupling (LRC) is a universal phenomenon reported for various forms of rhythmic exercise. In this study, we investigated the effect of movement and respiratory frequencies on LRC. Participants were instructed to cycle or breath in synchrony with a periodic auditory stimulation at preferred and non-preferred frequencies. LRC stability was assessed by frequency and phase coupling indexes using the theory of nonlinear coupled oscillators through the sine circle map model, and the Farey tree. Results showed a stabilizing effect of sound on LRC for all frequencies and for the two systems paced. The sound-induced effect was more prominent when the rhythm of the stimulation corresponded to the preferred frequencies. The adoption of cycling or respiratory frequencies far off preferential ones led to a loss of stability in LRC. Contrary to previous findings, our results suggest that LRC is not unidirectional-from locomotion onto respiration-but bidirectional between the two systems. They also suggest that auditory information plays an important role in the modulation of LRC.
Assuntos
Locomoção/fisiologia , Modelos Biológicos , Movimento/fisiologia , Dinâmica não Linear , Respiração/imunologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Periodicidade , Adulto JovemRESUMO
In patients with obstructive sleep apnea, airway obstruction during sleep produces hypercapnia, which in turn activates respiratory muscles that pump air into the lungs (e.g., the diaphragm) and that dilate and stabilize the upper airway (e.g., the genioglossus). We hypothesized that these responses are facilitated by glutamatergic neurons in the parabrachial complex (PB) that respond to hypercapnia and project to premotor and motor neurons that innervate the diaphragm and genioglossus muscles. To test this hypothesis, we combined c-Fos immunohistochemistry with in situ hybridization for vGluT2 or GAD67 or with retrograde tracing from the ventrolateral medullary region that contains phrenic premotor neurons, the phrenic motor nucleus in the C3-C5 spinal ventral horn, or the hypoglossal motor nucleus. We found that hypercapnia (10% CO2 for 2 hours) activated c-Fos expression in neurons in the external lateral, lateral crescent (PBcr), and Kölliker-Fuse (KF) PB subnuclei and that most of these neurons were glutamatergic and virtually none γ-aminobutyric acidergic. Numerous CO2 -responsive neurons in the KF and PBcr were labeled after retrograde tracer injection into the ventrolateral medulla or hypoglossal motor nuclei, and in the KF after injections into the spinal cord, making them candidates for mediating respiratory-facilitatory and upper-airway-stabilizing effects of hypercapnia.