The effect of bronchodilation and spirometry on fractional exhaled nitric oxide (FeNO50), bronchial NO flux (JawNO) and alveolar NO concentration (CANO) in children and young adults

Mechanisms of Bushenyiqi decoction in the treatment of asthma: an investigation based on network pharmacology with experimental validation

Background and purpose: The Bushenyiqi decoction (BYD), a contemporary prescription of traditional Chinese medicine (TCM), has been observed to significantly ameliorate asthma symptoms in patients based on clinical observations. Although multi-component and multi-target characteristics are important attributes of BYD treatment, its pharmacological effect on asthma and the underlying mechanism of action remain unclear. Method: Network pharmacology: the asthma-related genes were retrieved from the GeneCards and OMIM database. The active constituents of BYD and their corresponding target genes were collected from the TCMSP database. The underlying pathways associated with overlapping targets between BYD and asthma were identified through GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis. Experimental validation: pulmonary function tests, enzyme-linked immunosorbent assay (ELISA), Hematoxylin and eosin (HE), periodic acid-Schiff (PAS), and Masson's trichrome stainings were conducted to validate the efficacy of BYD in ameliorating airway inflammation in allergic asthma mice. Western blot (WB) and molecular docking were performed to confirm the involvement of the underlying pathway in BYD treatment of asthma. Results: The results of animal experiments demonstrated that BYD may improve airway responsiveness and suppress airway inflammation in allergic asthma mice. The network pharmacological analysis revealed the involvement of 11 potentially key active components, 9 potential key targets, and the phosphatidylinositol3 kinase-RAC-α serine/threonine-protein kinase (PI3K/AKT) signaling pathway in the mechanism of action of BYD for asthma treatment. Our findings have confirmed that BYD effectively alleviated airway inflammation by targeting interleukin 6 (IL-6), epidermal growth factor receptor (EGFR), and hypoxia inducible factor 1 alpha (HIF1A), with quercetin, kaempferol, and luteolin performing as the pivotal active constituents. BYD may potentially reduce inflammatory cell infiltration in lung tissues by regulating the PI3K/AKT signaling pathway. Conclusion: In conclusion, the integration of network pharmacology and biological experiments has demonstrated that key constituents of BYD, such as quercetin, kaempferol, and luteolin, exhibit targeted effects on IL-6, EGFR, and HIF1A in combating asthma-related inflammation through inhibition of the PI3K/AKT signaling pathway. The findings of this investigation provide evidence supporting the effectiveness of TCM's "bushenyiqi" therapy in asthma management, as corroborated by contemporary medical technology.

Effects of the salbutamol bronchodilator response on measurements of fractional exhaled nitric oxide in children with asthma: a prospective, observational study

BACKGROUND

Salbutamol bronchodilator response (BDR) test and fractional exhaled nitric oxide (FeNO) have been recommended for the diagnosis of asthma in children, but FeNO levels is affected by many factors. Nonetheless, data of the effect on the FeNO values throughout the bronchodilator test and the differences in FeNO values between BDR positive (BDR+) and negative (BDR-) children with asthma are still limited. We aimed to evaluate the effect of the BDR test on FeNO and the differences in FeNO levels between BDR+ and BDR- children with asthma.

METHODS

This was a prospective, observational study performed over a 5-month period (December 2018 to April 2019) and involved 57 children with asthma. The FeNO levels at pre-spirometry, post-spirometry, and post-salbutamol BDR testing were estimated. Finally, the children were divided into two groups i.e., BDR+ and BDR-, and differences in the FeNO levels were compared between the two groups.

RESULTS

The spirometry results were normal in 2 patients (3.5%). There were 53 (93%) patients with obstructive lung disease, including 40 (70.2%), 11 (19.3%), and 2 (3.5%) patients with mild, moderate, and severe obstruction, respectively. The remaining two patients had mixed lesions (3.5%), none of which were restrictive. The baseline median FeNO levels were significantly higher in the BDR+ group than in the BDR- group [33.00 (23.78, 46.73) vs. 23.00 (9.80, 37.80), (P=0.048)]. Following spirometry, there was a statistically significant decrease in median FeNO levels from baseline to post-spirometry (P=0.002). However, there was no significant difference between the median FeNO levels at baseline and following the BDR test (P=0.976). The impact of spirometry on FeNO was not statistically different in BDR+ versus BDR- children (Z=-0.186, P=0.853); however, the impact of bronchodilators on FeNO exhibited a statistically significant difference between the two groups (Z=3.160, P=0.002).

CONCLUSIONS

This study revealed dynamic changes in the FeNO levels during the BDR test. The use of a bronchodilator results in a statistically significant difference in FeNO levels between BDR+ and BDR- children with asthma. Moreover, spirometry leads to a marked decrease in the FeNO levels. Our results will allow clinicians to better interpret FeNO, BDR and pulmonary function outcomes and better develop clinical protocols.

Elevated Levels of Alveolar Nitric Oxide May Indicate Presence of Small Airway Inflammation in Patients with Inflammatory Bowel Disease

INTRODUCTION

Pulmonary manifestations of inflammatory bowel disease (IBD), albeit not rare, are largely overlooked in clinical practice. The role of exhaled nitric oxide (eNO) as an established biological marker of airway inflammation compels us to use it as a tool to investigate the exact nature of these manifestations.

METHODS

Fractional eNO (FeNO) was measured in multiple flows, and with the use of a mathematical model, alveolar concentration of NO (CANO) and bronchial flux of NO (JawNO) were assessed in 27 patients with IBD [17 with Crohn's disease (CD) and 10 with ulcerative colitis (UC)] and in 39 healthy controls. Carefully selected criteria were used to exclude patients or healthy controls that presented factors considered to be correlated with eNO measurements. Disease activity was measured in Crohn's patients using the CD activity index (CDAI) score and in UC using the partial Mayo score.

RESULTS

CANO was significantly higher in the IBD group, compared to the control group (p < 0.0001). FeNO was significantly increased in patients with IBD (p = 0.023), while there was no statistical significance found regarding levels of JawNO in patients with IBD (p = 0.106), both compared to controls. There was no significant correlation between any eNO component and markers of disease activity.

CONCLUSIONS

Alveolar concentration of NO is elevated in patients with IBD, regardless of disease activity. This may suggest that subclinical small airway inflammation is present in patients with IBD, even those with mild or inactive disease.

Flow-independent nitric oxide parameters in asthma: a systematic review and meta-analysis

INTRODUCTION

Fractional exhaled nitric oxide (F_ENO) has been proposed as a non-invasive marker of inflammation in the lungs. Measuring F_ENO at several flow rates enables the calculation of flow independent NO-parameters that describe the NO-exchange dynamics of the lungs more precisely. The purpose of this study was to compare the NO-parameters between asthmatics and healthy subjects in a systematic review and meta-analysis.

METHODS

A systematic search was performed in Ovid Medline, Web of Science, Scopus and Cochrane Library databases. All studies with asthmatic and healthy control groups with at least one NO-parameter calculated were included.

RESULTS

From 1137 identified studies, 33 were included in the meta-analysis. All NO-parameters (alveolar NO concentration (C_ANO), bronchial flux of NO (J_awNO), bronchial mucosal NO concentration (C_awNO) and bronchial wall NO diffusion capacity (D_awNO)) were found increased in glucocorticoid-treated and glucocorticoid-naïve asthma. J_awNO and C_ANO were most notably increased in both study groups. Elevation of D_awNO and C_awNO seemed less prominent in both asthma groups.

DISCUSSION

We found that all the NO-parameters are elevated in asthma as compared to healthy subjects. However, results were highly heterogenous and the evidence on C_awNO and D_awNO is still quite feeble due to only few studies reporting them. To gain more knowledge on the NO-parameters in asthma, nonlinear methods and standardized study protocols should be used in future studies.