The management of asthma in the phenotype and biomarker era: The proposal of a new diagnostic-therapeutic model

Yanghepingchuan granule improves airway inflammation by inhibiting autophagy via miRNA328-3p/high mobility group box 1/Toll-like receptor 4 targeting of the pathway of signaling in rat models of asthma

BACKGROUND

As a type of traditional Chinese medicine, Yanghepingchuan granules (YHPCG) are used to treat inflammatory diseases of the lungs, including asthma. However, the underlying molecular mechanism of the ability of YHPCG to reduce airway inflammation remains unknown.

METHODS

By sensitizing rats to aluminum hydroxide and ovalbumin, an asthma model was established. During the 14-day treatment period, the rats received YHPCG, TAK242 (TLR4 inhibitor), and a combination of the two treatments. Histopathology and goblet cell hyperplasia were observed in rats with ovalbumin-induced asthma by using hematoxylin-eosin (HE) and periodic acid-Schiff (PAS) staining. Immunohistochemical, autophagy-related immunofluorescence, and western blotting analyses were performed to determine autophagic activity. The effects of YHPCG on high mobility group box 1 (HMGB1)-mediated Toll-like receptor 4 (TLR4)/nuclear factor κB (NF-κB) pathway-related proteins and inflammatory factors in rats were evaluated via western blotting, PCR analysis, and enzyme-linked immunosorbent assay. A dual luciferase method was used to detect the interaction between miRNA328-3p and HMGB1.

RESULTS

YHPCG inhibit the HMGB1/TLR4/NF-κB pathway by upregulating miR-328-3p, reducing autophagosome production, inhibiting autophagy, and effectively preventing the progression of lung inflammation.

CONCLUSIONS

Asthma airway inflammation can be treated with YHPCG by inhibiting autophagy via miRNA328-3p/HMGB1/TLR4/NF-κB signaling pathways.

Long non-coding RNA TUG1 promotes proliferation and migration in PDGF-BB-stimulated HASMCs by regulating miR-216a-3p/SMURF2 axis

BACKGROUND

Abnormal proliferation and migration of human airway smooth muscle cells (HASMCs) play an important role in the development of childhood asthma. Long non-coding RNAs (lncRNAs) have been demonstrated to participate in HASMC proliferation and migration. We aimed to explore more effects and molecular mechanism of taurine upregulated gene 1 (TUG1) in childhood asthma.

RESULTS

TUG1 and SMURF2 were overexpressed and miR-216a-3p was downregulated in childhood asthma patients and PDGF-BB-stimulated HASMCs. TUG1 knockdown attenuated PDGF-BB-triggered proliferation and migration of HASMCs. MiR-216a-3p was targeted by TUG1, and miR-216a-3p suppression counteracted the repressive effects of TUG1 interference on proliferation and migration in PDGF-BB-treated HASMCs. SMURF2 was a downstream target of miR-216a-3p, and SMURF2 upregulation abated the inhibiting effects of miR-216a-3p on migration and proliferation in PDGF-BB-exposed HASMCs. TUG1 sponged miR-216a-3p to positively regulate SMURF2 expression.

CONCLUSION

TUG1 downregulation inhibited PDGF-BB-induced HASMC proliferation and migration by regulating miR-216a-3p/SMURF2 axis, offering novel insight into the potential application of TUG1 for childhood asthma treatment.

Glycyrrhizic acid restrains airway inflammation and remodeling in asthma via the TGF-β1/Smad signaling pathway

The anti-inflammatory effects of glycyrrhizic acid (GA) against asthma have previously been reported; however, the underlying molecular mechanism of GA in asthma has not yet been elucidated. Thus, the present study aimed to determine the function and potential molecular mechanism of GA for modulating the transforming growth factor-β1 (TGF-β1)/Smad signaling pathway in asthma-associated airway inflammation and remodeling. In order to study the mechanism of GA on airway inflammation and airway remodeling in asthmatic mice, a mouse model of chronic asthma was constructed. A total of 50 female mice were randomly assigned into five groups (10 mice/group), as follows: Blank group, asthma group, GA group, dexamethasone group and GA + TGF-β1 group. Hematoxylin and eosin, and Masson staining were performed to assess the airway inflammation and remodeling in mice with ovalbumin (OVA)-induced asthma. The serum levels of interleukin (IL)-4, IL-5, IL-13 and IL-17 in mice were assessed via the enzyme-linked immunosorbent assay. Reverse transcription-quantitative PCR and western blot analyses were performed to detect the levels of TGF-β1 and Smads in lung tissues of each group of mice. The results demonstrated that GA and dexamethasone treatment mitigated airway inflammation, inflammatory cell infiltration and airway remolding, with a concomitant decrease in the expression levels of IL-4, IL-5, IL-13 and IL-17, in mice with OVA-induced asthma. In addition, the levels of TGF-β1 and Smad2 notably decreased, while Smad7 expression increased in the GA and dexamethasone groups compared with the asthma group. Furthermore, histopathological morphometry exhibited significantly elevated inflammatory cell infiltration, airway wall and smooth muscle, collagen secretion and inflammatory cytokines in the serum of mice in the GA + TGF-β1 group compared with the GA group. Taken together, the results of the present study suggest that GA ameliorates airway inflammation and remodeling via the TGF-β1/Smad signaling pathway in mice with asthma.

Obesity May Provide Pro-ILC3 Development Inflammatory Environment in Asthmatic Children

The prevalence of obesity in children has dramatically increased in the last few decades, and obesity has also emerged as an important risk factor for asthma. Innate mechanisms have been shown to be involved in both diseases, particularly through the recently described innate lymphoid cells (ILCs), in which ILC3s have been linked to obesity both in human and in murine models. The aim of this study was to explore whether being overweight in asthmatic children was associated with elevated circulating ILC3 or elevated messenger RNA (mRNA) levels of RORC, IL-17A, and IL-22. Our results showed significantly elevated ILC3 frequencies in overweight asthmatic children compared with nonoverweight controls based on the detection of Lin+CD127+IL-23R+ cells by flow cytometry. Moreover, elevated ILC3 frequencies positively correlated with the mRNA expression of RORC which has been identified as a transcription factor of ILC3s. The relative mRNA expression level of IL-17A was also upregulated in overweight compared to nonoverweight children, as was the relative mRNA level of IL-22. However, there were no correlations between ILC3 frequencies or the expressions of RORC, IL-17A, and IL-22 and asthma severity. These results suggested that childhood obesity is an independent factor that is associated with an elevated frequency of circulating ILC3s and higher expressions of RORC, IL-22, and IL-17A.

The evidence on tiotropium bromide in asthma: from the rationale to the bedside

Severe and poorly controlled asthma still accounts for a great portion of the patients affected. Disease control and future risk management have been identified by international guidelines as the main goals in patients with asthma. The need for new treatment approaches has led to reconsider anticholinergic drugs as an option for asthma treatment. Tiotropium is the first anticholinergic drug that has been approved for children and adults with poorly controlled asthma and is currently considered as an option for steps 4 and 5 of the Global Initiative for Asthma. In large randomized clinical trials enrolling patients with moderate to severe asthma, add-on therapy with tiotropium has demonstrated to be efficacious in improving lung function, decreasing risk of exacerbation and slowing the worsening of disease; accordingly, tiotropium demonstrated to be non inferior compared to long acting beta-agonists in the maintenance treatment along with medium to high inhaled corticosteroids. In view of the numerous ancillary effects acting on inflammation, airway remodeling, mucus production and cough reflex, along with the good safety profile and the broad spectrum of efficacy demonstrated in different disease phenotypes, tiotropium can represent a beneficial alternative in the therapeutic management of poorly controlled asthma. The present extensive narrative review presents the pharmacological and pathophysiological basis that guided the rationale for the introduction of tiotropium in asthma treatment algorithm, with a particular focus on its conventional and unconventional effects; finally, data on tiotropium efficacy and safety. from recent randomized clinical trials performed in all age categories will be extensively discussed.

Asthma management in a specialist setting: Results of an Italian Respiratory Society survey

BACKGROUND

Asthma considerably impairs patients' quality of life and increases healthcare costs. Severity, morbidity, and degree of disease control are the major drivers of its clinical and economic impact. National scientific societies are required to monitor the application of international guidelines and to adopt strategies to improve disease control and better allocate resources.

AIM

to provide a detailed picture of the characteristics of asthma patients and modalities of asthma management by specialists in Italy and to develop recommendations for the daily management of asthma in a specialist setting.

METHOD

A quantitative research program was implemented. Data were collected using an ad hoc questionnaire developed by a group of specialists selected by the Italian Pneumology Society/Italian Respiratory Society.

RESULTS

The records of 557 patients were analyzed. In the next few years, specialists are expected to focus their activity patients with more severe disease and will be responsible for selection of patients for personalized biological therapy; however, only 20% of patients attending Italian specialist surgery can be considered severe. In 84.4% of cases, the visit was a follow-up visit requested in 82.2% of cases by the specialist him/herself. The Asthma Control Test is used only in 65% of patients. When available, a significant association has been observed between the test score and asthma control as judged by the physician, although concordance was only moderate (κ = 0.68). Asthma was considered uncontrolled by the specialist managing the case in 29.1% of patients; nevertheless, treatment was not stepped up in uncontrolled or partly controlled patients (modified in only 37.2% of patients).

CONCLUSIONS

The results of this survey support re-evaluation of asthma management by Italian specialists. More resources should be made available for the initial visit and for more severely ill patients. In addition, more extensive use should be made of validated tools, and available drugs should be used more appropriately.