Interleukin-22 attenuates allergic airway inflammation in ovalbumin-induced asthma mouse model

Endoplasmic reticulum stress drives macrophages to produce IL-33 to favor Th2 polarization in the airways

Interleukin (IL)-33 is a key driver of T helper 2 (Th2) cell polarization. Endoplasmic reticulum (ER) stress plays a role in the skewed T cell activation. The objective of this project is to elucidate the role of IL-33 derived from macrophages in inducing Th2 polarization in the airways. In this study, bronchoalveolar lavage fluids (BALF) were collected from patients with asthma and healthy control subjects. Macrophages were isolated from the BALF by flow cytometry cell sorting. An asthmatic mouse model was established using the ovalbumin/alum protocol. The results showed that increased IL33 gene activity and ER stress-related molecules in BALF-derived M2a macrophages was observed in asthmatic patients. Levels of IL33 gene activity in M2a cells were positively correlated with levels of asthma response in asthma patients. Sensitization exacerbated the ER stress in the airway macrophages, which increased the expression of IL-33 in macrophages of airway in sensitized mice. Conditional ablation of Il33 or Perk or Atf4 genes in macrophages prevented induction of airway allergy in mice. In conclusion, asthma airway macrophages express high levels of IL-33 and at high ER stress status. Inhibition of IL-33 or ER stress in macrophages can effectively alleviate experimental asthma.

Interleukin-22 and acute pancreatitis: A review

Acute pancreatitis (AP) is one of the most common gastrointestinal diseases, and it is divided into 3 types according to its severity:mild acute pancreatitis, moderately severe acute pancreatitis, and severe acute pancreatitis. The mortality in severe acute pancreatitis is approximately 15% to 30% due to multiorgan dysfunction and the lack of specific treatment. Interleukin-22 (IL-22) is a member of the Interleukin-10 family, and it can activate several downstream signaling pathways by binding to its receptor complex, thus it is involved in cell differentiation, proliferation, and apoptosis. Some studies have reported the elevated level of IL-22 in patients with AP, which suggests IL-22 may be involved in the pathogenesis of AP. And many studies have shown that IL-22 had a protective effect against AP. This article reviews the characteristics and mechanism of IL-22 and its role in AP to provide insight into the treatment of AP.

Artesunate inhibits airway remodeling in asthma via the MAPK signaling pathway

Background: Artesunate (ART), is a semi-synthetic water-soluble artemisinin derivative extracted from the plant Artemisia annua, which is often used to treating malaria. In vivo and in vitro studies suggested it may help decrease inflammation and attenuate airway remodeling in asthma. However, its underlying mechanism of action is not elucidated yet. Herein, an attempt is made to investigate the ART molecular mechanism in treating asthma.

Methods: The BALB/c female mice sensitized via ovalbumin (OVA) have been utilized to establish the asthma model, followed by carrying out ART interventions. Lung inflammation scores by Haematoxylin and Eosin (H&E), goblet cell hyperplasia grade by Periodic Acid-Schiff (PAS), and collagen fibers deposition by Masson trichrome staining have been utilized for evaluating how ART affected asthma. RNA-sequencing (RNA-seq) analyses were performed to identify differentially expressed genes (DEGs). The DEGs were analyzed by Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and Protein-Protein interaction (PPI) function analyses. Hub clusters were found by Cytoscape MCODE. Subsequently, Real-Time quantitative PCR (RT-qPCR) verified the mRNA expression profiles of DEGs. Finally, immunohistochemistry (IHC) and western blots have validated the relevant genes and potential pathways.

Results: ART considerably attenuated inflammatory cell infiltration, mucus secretion, and collagen fibers deposition. KEGG pathway analysis revealed that the ART played a protective role via various pathways including the mitogen-activated protein kinase (MAPK) pathway as one of them. Moreover, ART could alleviate the overexpression of found in inflammatory zone 1(FIZZ1) as revealed by IHC and Western blot analyses. ART attenuated OVA-induced asthma by downregulating phosphorylated p38 MAPK.

Conclusion: ART exerted a protective function in a multitarget and multi-pathway on asthma. FIZZ1 was a possible target for asthma airway remodeling. The MARK pathway was one of the key pathways by which ART protected against asthma.

Screening of Q-markers for the wine-steamed Schisandra chinensis decoction pieces in improving allergic asthma

BACKGROUND

Traditional Chinese medicine (TCM) posits that Chinese medicinal materials can only be clinically used after being processed and prepared into decoction pieces. Schisandra Chinensis Fructus (derived from the dried and mature fruits of Schisandra chinensis (Turcz.) Baill.) has been used as a traditional antiasthmatic, kidney strengthening, and hepatoprotective agent for 2000 years. The results of previous research show that decoction pieces of wine-steamed Schisandra chinensis (WSC) are more effective than raw decoction pieces of Schisandra chinensis (RSC) for treating cough and asthma. Steaming with wine was demonstrated to promote the dissolution of ingredients. However, the relationship between the changes in the components of the decoction pieces of WSC and the therapeutic effect remains unclear.

METHODS

The efficacies of decoctions of RSC and WSC were compared using allergic asthma rats. The potential bioactive components in the serum of the WSC treatment group and the changes in the chemical composition of the RSC decoction pieces before and after wine steaming were determined by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) and ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC H-CLASS XEVO TQD) to speculate quality markers (Q-markers) related to the efficacy of WSC, which were subsequently verified based on a zebrafish inflammation model.

RESULTS

Steaming RSC decoction pieces with wine was found to promote improvement of allergic asthma. Reverse tracing of 22 components detected in the serum of the high dose group of WSC (WSC-H) resulted in 12 ingredients being finally designated as potential effective components. Among these ingredients, 5 components, Schisandrin, Schisandrol B, Schisandrin A, Schisandrin B, and Gomisin D, had higher dissolution rates than RSC after steaming with wine. Validation by an inflammatory zebrafish model showed that these 5 ingredients had a dose-dependent effect and were therefore Q-markers for WSC in the treatment of allergic asthma.

CONCLUSION

In this study, changes in the components of decoction pieces of RSC and WSC and Q-markers related to WSC efficacy were identified, providing valuable information for expanding the application of WSC and establishing a specific quality standard for WSC.

Role of IL-22 in acute asthma mouse model

Introduction: Allergic asthma is often associated with eosinophilic inflammation, which is related to the T-helper cell type 2 (Th2) cytokines and responsive to corticosteroids. However, there are also phenotypes of non-Th2-mediated asthma, which have poor responsivity to corticosteroids. The leading phenotype of non-Th2-mediated asthma is neutrophilic asthma, which is considered difficult to treat. Recently, IL-22 has been found to be involved in neutrophilic inflammation in asthma. However, studies on the role of IL-22 in asthma are still controversial as IL-22 has both pro-inflammatory and anti-inflammatory roles in asthma. This study examined whether the IL-22 level increased in acute neutrophilic asthma in the mouse model. Herein, we aimed to demonstrate increased IL-22 levels in neutrophilic asthma and elucidate the pathways leading to elevated neutrophil counts.Methods: Six-week old female BALB/c mice were sensitized and challenged with PBS, ovalbumin (OVA) or OVA + lipopolysaccharide (LPS). The mice were then assigned to one of the following five groups: (1) control (PBS/ PBS), (2) OVA/PBS, (3) OVA/OVA, (4) OVA+LPS/PBS, (5) OVA+LPS/OVA+LPS.Results: The levels of Th2 cytokines, IL-17, and IL-22 were assessed, with investigation of the neutrophil chemokines. This study showed that in the acute neutrophilic asthma, the levels of IL-17 and IL-22 were significantly higher than those in the OVA/OVA group, which represents acute eosinophilic asthma. Moreover, the level of CCL20 increased in the neutrophilic asthma group.Conclusion: Thus, this study suggests that in the acute neutrophilic asthma mouse model, IL-17 and IL-22 may increase with CCL20, resulting in neutrophilic inflammation.

Chemical Characterization and Potential Mechanism of the Anti-Asthmatic Activity of a Subfraction from Schisandra chinensis Fruit Extract

Schisandra chinensis fruit is a widely edible and medicinal resource, whose extract had a good inhibitory effect on airway inflammation in asthmatic mice. However, the main active components remain unknown. In this work, we found that PET2, a subfraction of its ethanolic extract petroleum ether, displayed significant anti-inflammatory effects in interleukin (IL)-4/tumor necrosis factor (TNF)-α-stimulated BEAS-2B cells. Meanwhile, in the ovalbumin (OVA)-induced allergic asthma mice model, PET2 (200 and 400 mg/kg) had significant effects on attenuating airway inflammatory cell infiltration and reducing serum Th2-related cytokines. Further studies led to the isolation and identification of 14 compounds, guided by ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based rapid characterization of chemical constituents. Combining network pharmacology analysis and in vitro experiments, we found that six compounds from PET2 had good anti-inflammatory properties. The potential mechanism may be involved in Fc epsilon RI, T cell receptor, and Jak-STAT signaling pathways. This study clarified the anti-inflammatory properties of the main active fraction and active compounds of S. chinensis fruit and provided a theoretical basis for its anti-asthma scientific utilization.

The Roles of IL-22 and Its Receptor in the Regulation of Inflammatory Responses in the Brain

Interleukin (IL)-22 is a potent mediator of inflammatory responses. The IL-22 receptor consists of the IL-22Rα and IL-10Rβ subunits. Previous studies have shown that IL-22Rα expression is restricted to non-hematopoietic cells in the skin, pancreas, intestine, liver, lung, and kidney. Although IL-22 is involved in the development of inflammatory responses, there have been no reports of its role in brain inflammation. Here, we used RT-PCR, Western blotting, flow cytometry, immunohistochemical, and microarray analyses to examine the role of IL-22 and expression of IL-22Rα in the brain, using the microglial cell line, hippocampal neuronal cell line, and inflamed mouse brain tissue. Treatment of BV2 and HT22 cells with recombinant IL-22 increased the expression levels of the pro-inflammatory cytokines IL-6 and TNF-α, as well as cyclooxygenase (COX)-2 and prostaglandin E2. We also found that the JNK and STAT3 signaling pathways play an important role in IL-22-mediated increases in inflammatory mediators. Microarray analyses revealed upregulated expression of inflammation-related genes in IL-22-treated HT22 cells. Finally, we found that IL-22Rα is spontaneously expressed in the brain and is upregulated in inflamed mouse brain. Overall, our results demonstrate that interaction of IL-22 with IL-22Rα plays a role in the development of inflammatory responses in the brain.