Oxidative Stress and Nutritional Intakes in Lung Patients With Bronchiolitis Obliterans Syndrome

Anti-oxidative effect of the tyrosine kinase inhibitor nintedanib: a potential therapy for chronic lung allograft dysfunction?

Background: The long-term survival after lung transplantation (LTx) is often limited by the development of chronic lung allograft dysfunction (CLAD). Increased oxidative stress has been found to occur in chronic lung allograft dysfunction because of several risk factors, e.g. immunological factors or drug related factors. The aim of this study was to investigate the anti-oxidative effect of the receptor tyrosine kinase (RTK) inhibitor nintedanib on immunologically induced oxidative stress and on drug induced oxidative stress.Methods: In-vivo studies were used for investigation of immunologically induced oxidative stress: Immunohistochemistry of transglutaminase-2 (TGM-2) was used to figure out a potential anti-oxidative effect of receptor tyrosine kinase inhibitor nintedanib in a rat model of allogeneic left LTx. In-vitro studies were used for investigation of drug induced oxidative stress: Cell viability assay, 2'7'-dichlorodihydrofluorescein diacetate (DCFDA) and immunofluorescence of transglutaminase-2 were disposed to examine the potential impact of nintedanib on cyclosporin A (CsA) treated lung fibroblasts of the rat.Results: In-vivo studies: Allogeneic transplanted animals without drug interaction showed severe chronic rejection and an excessive expression of TGM-2, whereas the application of nintedanib significantly decreased the number of TGM-2 positive cells. In-vitro studies: Concentrations of CsA ranging from 250 ng/ml to 500 ng/ml demonstrated oxidative stress caused by an increased production of reactive oxygen species (ROS) and an overexpression of TGM-2 without inducing apoptosis in cells. Concentrations of more than 1000 ng/ml led to a considerable decrease of cellularity. 30 min-pre-incubation with nintedanib at a concentration between 25 and 100 nM reduced generation of intracellular ROS and expression of TGM-2.Conclusion: These results demonstrate a downregulation of ROS and TGM-2 by pretreatment with the receptor tyrosine kinase inhibitor nintedanib and present its potential anti-oxidative and immunomodulatory effect in the treatment of chronic lung allograft dysfunction.

Respiratory

Lung disease rivals the position for the top cause of death worldwide. Causes and pathology of the myriad lung diseases are varied, yet nutrition can either affect the outcome or support treatment in the majority of cases. This chapter explores the modifiable risk factors, from lifestyle changes to dietary intake to specific nutrients, anti-nutrients, and toxins helpful for the nutritionist or dietitian working with lung disease patients. General lung health is discussed, and three major disease states are explored in detail, including alpha-1 antitrypsin deficiency, asthma, and idiopathic pulmonary fibrosis. Although all lung diseases have diverse causes, many integrative and functional medical nutrition therapies are available and are not being utilized in practice today. This chapter begins the path toward better nutrition education for the integrative and functional medicine professional.

Bronchiolitis obliterans murine model induced by nitric acid aerosol inhalation: An economical and reproducible model

PURPOSE

Bronchiolitis obliterans (BO) is a highly debilitative and fatal syndrome associated with a series of severe lower airway disorders. The pathogenesis of BO is complicated and not entirely understood. An appropriate animal model of BO may aid research into its pathogenesis. Here, we establish a mouse model of BO to provide insight into this disease.

MATERIALS AND METHODS

6-8 week old BABL/c mice were exposed to 5% nitric acid (NA) aerosol through a nebulizer for 3 hours, and controls were exposed to distilled water instead. Symptoms, airway resistance and pathological process were observed dynamically. The levels of matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), 8-isoprostane and myeloperoxidase (MPO) in lung tissue and bronchoalveolar lavage fluids (BLAF) were determined by ELISA on day 3, 7, 14, 28 and 56 after the aerosol nebulization.

RESULTS

Typical BO lesions were observed in NA nebulized mice characterized histologically by initial necrotizing bronchiolitis and final airway fibrosis at day 28 after the aerosol nebulization. NA nebulized mice also exhibited labored breathing and significantly increased airway resistance. Expression of MMP-2, MMP-9, TIMP-1, 8-isoprostane and MPO were significantly elevated in NA nebulized mice in different time frame.

CONCLUSION

A murine BO model was established by NA aerosol inhalation. It provides an easy, economic, and reproducible mice model for BO research.

Short-Term Variation of Lung Function and Airway Inflammation in Children and Adolescents with Bronchiolitis Obliterans

PURPOSE

Bronchiolitis obliterans (BO) is an inadequately researched disease in terms of lung function as well as inflammatory profile. The short-term variation of these parameters has not been investigated. Therefore, the objective of this study was the investigation of lung function, sputum cells and cytokine profiles in BO at two visits within of four to six weeks.

METHODS

Twenty patients with BO (median age = 14.6, range 8.3-24.3) performed lung function tests, airway reversibility testing and induction of sputum within four to six weeks. The cell composition in the sputum was analysed and cytokine levels of IL-1ß, IL-6 and IL-8 were determined by cytometric bead array analysis. The short-term variation was then statistically quantified and compared to that of twenty-two healthy controls. Furthermore, we compared data on short-term variation of lung function and airway inflammation with a previous investigation in these patients 10-15 months earlier.

RESULTS

Patients with BO showed minimal variation of lung function (VCmax, FVC, FEV1, FEV1/VC, MEF25 and RV/TLC) and the inflammatory cell profile. The lung function data were significantly lower for FVC, FEV1, the Tiffeneau index and MEF25 compared to the control group, whereas RV/TLC was significantly increased. Analysis of the BO sputum cells showed a consistent neutrophil inflammation. The levels of inflammatory cytokines IL-1ß, IL-6 and IL-8 had a great variability.

CONCLUSIONS

The short-term variability of sputum neutrophilia and lung function is low in BO patients. This finding should be considered to identify successful treatment in the individual patient and could be used as endpoints for future BO-related studies.

Infectious episodes lead to the oxidative stress response after lung transplantation

Case series

Patient: Male, 30 • Female, 44

Final Diagnosis: Post-transplant respiratory infection

Symptoms: Oxidative stress

Medication: —

Clinical Procedure: —

Specialty: Transplantology

Airway inflammation in children and adolescents with bronchiolitis obliterans

BACKGROUND

Airway inflammation plays a major role in the progression of chronic lung diseases. The features of airway inflammation are not well defined among patients with cases of bronchiolitis obliterans (BO) that began in childhood.

OBJECTIVES

To investigate the sputum cell and cytokine profiles of stable cases of BO regarding lung function and the involvement of small airway disease (SAD).

METHODS

Twenty patients with BO (median age=14.5, range=7-23years) and 22 healthy controls (median age=16.5years, range=7-24years) were investigated. Lung function parameters and bronchial reversibility testing as well as sputum cell and cytokine profiles (IL-1β, IL-6, IL-8, TNF-α, IL-5, IFN-γ, and NFκB regulation) were analysed using quantitative RT-PCR and cytometric bead assay (CBA) in induced sputum.

RESULTS

Patients with BO had significantly lower lung function values, including FVC, forced expiratory volume (FEV1), the Tiffeneau index (FEV1/VC), and MEF25, but increased functional residual capacity (RV/TLC) values. Bronchial reversibility was found in five patients (25%). Moreover, airway inflammation (as indicated by total cells, neutrophils, IL-1β, IL-6, IL-8, TNF-α, and NFκB) was significantly increased among patients with BO compared with controls.

CONCLUSIONS

BO is predominantly a neutrophilic disease of the small bronchioles featuring elevated levels of pro-inflammatory cytokines leading to tissue remodelling and fibrosis of the small airways. Future therapies for patients with BO should more efficiently target the small airways.

Bronchoalveolar lavage as a tool to predict, diagnose and understand bronchiolitis obliterans syndrome

Bronchiolitis obliterans syndrome (BOS), a condition of irreversible small airway fibrosis, is the principal factor limiting long-term survival after lung transplantation. Bronchoscopy and bronchoalveolar lavage (BAL), techniques central to lung transplant clinical practice, provide a unique opportunity to interrogate the lung allograft during BOS development and identify potential disease mechanisms or biomarkers. Over the past 20 years, numerous studies have evaluated the BAL cellular composition, cytokine profiles and protein constituents in lung transplant recipients with BOS. To date, however, no summative evaluation of this literature has been reported. We developed and applied objective criteria to qualitatively rank the strength of associations between BAL parameters and BOS in order to provide a comprehensive and systematic assessment of the literature. Our analysis indicates that several BAL parameters, including neutrophil count, interleukin-8, alpha defensins and MMP-9, demonstrate highly replicable associations with BOS. Additionally, we suggest that considerable opportunity exists to increase the knowledge gained from BAL analyses in BOS through increased sample sizes, covariant adjustment and standardization of the BAL technique. Further efforts to leverage analysis of BAL constituents in BOS may offer great potential to provide additional in-depth and mechanistic insights into the pathogenesis of this complex disease.