Reduction/elimination of blood eosinophils in severe asthma: should there be a safety consideration?

Rhizoma Dioscoreae Nipponicae Relieves Asthma by Inducing the Ferroptosis of Eosinophils and Inhibiting the p38 MAPK Signaling Pathway

Rhizoma Dioscoreae Nipponicae (RDN) is a traditional Chinese medicine that widely applied in the treatment of human diseases. This study aims to explore the therapeutic potential of RDN in asthma and the underlying mechanisms. A mouse model of asthma was established by the stimulation of ovalbumin (OVA). HE staining was performed to detect the pathological injuries of tracheal tissues. The protein expression of collagen I, FN1, α-SMA (airway remodeling markers), and p-p38 (a marker of the p38 MAPK pathway) were detected by Western blot. Eosinophils were then isolated from the model mice. Cell viability and ROS level were measured by CCK-8 and Flow cytometry, respectively. The mRNA expression of GPX4 and ACSL4 (ferroptosis markers) in eosinophils were measured by qRT-PCR. RDN significantly reduced the numbers of total cells and eosnophils in bronchoalveolar lavage fluid (BALF), inhibited inflammatory cell infiltration, and down-regulated remodeling markers (Collagen I, FN1, and α-SMA) in OVA-induced mice. The p38 MAPK pathway was blocked by the intervention of RDN in the model mice, and its blocking weakens the poor manifestations of OVA-induced asthma. In addition, RDN induced the ferroptosis of eosnophils both in vitro and in vivo. Blocking of the p38 MAPK pathway also enhanced the ferroptosis of eosnophils in vitro, evidenced by the decreased cell viability and GPX4 expression, and increased ROS level and ACSL4 expression. RDN induced the ferroptosis of eosinophils through inhibiting the p38 MAPK pathway, contributing to the remission of asthma.

A bibliometric and scientific knowledge map study of the drug therapies for asthma-related study from 1982 to 2021

Objective: Asthma drug research has been increasing yearly, and its clinical application value has increasingly attracted attention. This study aimed to analyze the development status, research hotspots, research frontiers, and future development trends of the research works on drugs for patients with asthma, especially severe asthma.

Methods: Asthma drug-related articles published between 1982 and 2021 were retrieved from the Web of Science Core Collection (WOSCC) database, and only articles published in English were included. CiteSpace and VOSviewer software were utilized to conduct collaborative network analysis of countries/regions, institutions, keywords, and co-citation analysis of references.

Results: A total of 3,234 asthma drug-related eligible articles were included. The United States was in a leading position, and Karolinska Institute (Sweden) was the most active institution. The most prolific journal in this field was Journal of Asthma, and the most cited journal was Journal of Allergy and Clinical Immunology. Keyword co-occurrence studies suggested that the current hotspots and frontiers were as follows: ① asthma: fully revealing the potential of existing conventional asthma drugs, determining the best drug delivery system, and indicating the best combination. To continue to explore potential targets for severe asthma or other phenotypes. Inhaled glucocorticoids and budesonide are still one of the important aspects of current asthma drug research and ② severe asthma: the research and development of new drugs, especially monoclonal antibodies including omalizumab, mepolizumab, and benralizumab to improve asthma control and drug safety, have become a research hotspot in recent years, highlighting the importance of “target” selection.

Conclusion: This study demonstrates the global research hotspots and trends of the research works on drugs for patients with asthma/severe asthma. It can help scholars quickly understand the current status and hotspots of research in this field.

Eosinophilic inflammation: An Appealing Target for Pharmacologic Treatments in Severe Asthma

Severe asthma is characterized by different endotypes driven by complex pathologic mechanisms. In most patients with both allergic and non-allergic asthma, predominant eosinophilic airway inflammation is present. Given the central role of eosinophilic inflammation in the pathophysiology of most cases of severe asthma and considering that severe eosinophilic asthmatic patients respond partially or poorly to corticosteroids, in recent years, research has focused on the development of targeted anti-eosinophil biological therapies; this review will focus on the unique and particular biology of the eosinophil, as well as on the current knowledge about the pathobiology of eosinophilic inflammation in asthmatic airways. Finally, current and prospective anti-eosinophil therapeutic strategies will be discussed, examining the reason why eosinophilic inflammation represents an appealing target for the pharmacological treatment of patients with severe asthma.