Value of bronchial reversibility to salbutamol, exhaled nitric oxide and responsiveness to methacholine to corroborate the diagnosis of asthma in children

FoxO4 mediates macrophage M2 polarization by promoting LXA4R expression in an ovalbumin-induced allergic asthma model in mice

BACKGROUND

Asthma imposes a heavy burden due to its high prevalence. Forkhead box O4 (FoxO4) proteins participate in the modulation of cell progression. However, the role and mechanism of FoxO4 in asthma remains uncharted.

METHODS

An allergic asthma model was constructed by the induction of ovalbumin and interleukin (IL)-4 in mice and monocyte/macrophage-like Raw264.7 cells, respectively. The role and mechanism of FoxO4 in asthma was determined by pathological staining, immunofluorescence assay, measurement of inflammatory cells in the blood, reverse transcription quantitative polymerase chain reaction (RT-qPCR), Western blot analysis, and flow cytometry.

RESULTS

Ovalbumin treatment triggered an obvious inflammatory cell infiltration with a prominent increase in F4/80⁺ cell numbers. The relative messenger RNA (mRNA) and protein expressions of FoxO4 were increased in both ovalbumin-induced mice and interleukin-4 (IL-4)-induced Raw264.7 cells. Inhibition of FoxO4 via AS1842856 reduced inflammatory cell infiltration, the number of Periodic Acid Schiff+ (PAS+) goblet cells, the numbers of inflammatory cells in the blood, and the airway resistance in ovalbumin-induced mice. Besides, interference of FoxO4 decreased the number of F4/80⁺CD206⁺ cells, and the relative protein expressions of CD163 and Arg1 in vivo and in vitro. Mechanically, suppression of FoxO4 diminished the relative mRNA and protein expressions of LXA4R in both ovalbumin-induced mice and IL-4-induced Raw264.7 cells. Overexpression of LXA4R reversed the outcomes caused by repression of FoxO4, including airway resistance, the number of F4/80+ cells, the proportion of CD206+ cells in ovalbumin-induced mice, and the proportion of F4/80⁺CD206⁺ cells in IL-4-induced Raw264.7 cells.

CONCLUSION

FoxO4/LXA4R axis mediated macrophage M2 polarization in allergic asthma.

Is Bronchodilation Testing Routinely Useful in All Asthmatic Children?

Background: The reversibility of bronchial obstruction is needed to diagnose asthma. Bronchodilation (BD) testing is, therefore, used in asthma work-up. This study explored the benefit of performing BD testing in asthmatic children without bronchial obstruction. Methods: The study included 60 subjects with asthma and normal lung function, 13 (21.7%) females and 47 (78.3%) males; the mean age was 11.5 years, 26 were adolescents, and 34 were children. Lung function, symptoms, use of asthma medications, type 2 inflammation, and asthma control were assessed in all subjects. Results: Eleven (18%) subjects positively responded to BD testing. Fifty-five percent of subjects were uncontrolled based on Global Initiative for Asthma (GINA) criteria. The multivariate analysis identified 2 factors associated with a positive response to BD testing: FEV₁ [odds ratio (OR) = 0.91) and ACT (OR = 0.79). Conclusions: This study showed that BD testing could give additional helpful information in clinical practice. In addition, uncontrolled asthma, based on GINA criteria, was prevalent in children with normal lung function.

Precision Medicine and Childhood Asthma: A Guide for the Unwary

Many thousands of articles relating to asthma appear in medical and scientific journals each year, yet there is still no consensus as to how the condition should be defined. Some argue that the condition does not exist as an entity and that the term should be discarded. The key feature that distinguishes it from other respiratory diseases is that airway smooth muscles, which normally vary little in length, have lost their stable configuration and shorten excessively in response to a wide range of stimuli. The lungs' and airways' limited repertoire of responses results in patients with very different pathologies experiencing very similar symptoms and signs. In the absence of objective verification of airway smooth muscle (ASM) lability, over and underdiagnosis are all too common. Allergic inflammation can exacerbate symptoms but given that worldwide most asthmatics are not atopic, these are two discrete conditions. Comorbidities are common and are often responsible for symptoms attributed to asthma. Common amongst these are a chronic bacterial dysbiosis and dysfunctional breathing. For progress to be made in areas of therapy, diagnosis, monitoring and prevention, it is essential that a diagnosis of asthma is confirmed by objective tests and that all co-morbidities are accurately detailed.

The role of bronchodilation testing in children and adolescents with asthma in clinical practice

The change in forced expiratory volume in 1 s (FEV₁) in response to a bronchodilator (ΔFEV₁) is a diagnostic tool. Moreover, bronchodilation testing may give clinically relevant outcomes beyond diagnostic purposes. The present study aimed, therefore, to investigate the nationwide role of bronchodilation testing in daily practice. The study included 280 subjects, 202 (72.1%) males and 78 (27.9%) females; the mean age was 11.6 years. Notably, 67 (24%) children had bronchial reversibility (BDR). Age, initial FEV₁, FEV₁/FVC, and FVC were significantly associated with BDR (OR 1.16, 1.66, 0.71, and 0.67, respectively). Interestingly, 39 (58.2%) children with BDR had no bronchial obstruction. In conclusion, the BDR is usually associated with low values of the lung function parameters, even if within the normal ranges.