Systemic IL-6 and Severe Asthma

TNFSF11/TNFRSF11A Axis Amplifies HDM-Induced Airway Remodeling by Strengthening TGFβ1/STAT3 Action

PURPOSE

Asthma, an airway inflammatory disease, involves multiple tumor necrosis factors (TNF). TNF ligand superfamily member 11 (TNFSF11) and its known receptor, TNF receptor superfamily 11A (TNFRSF11A), has been implicated in asthma; however, the related mechanisms remain unknown.

METHODS

The serum and bronchial airway of patients with asthma and healthy subjects were examined. The air-liquid interface of primary human bronchial epithelial (HBE) cells, and Tnfsf11+/- mouse, Tnfrsf11a+/- mouse, and a humanized HSC-NOG-EXL mouse model were established. This study constructed short hairpin RNA (shRNA) of TNFSF11, TNFRSF11A, transforming growth factor β1 (TGFβ1), and transforming growth factor β receptor type 1 (TGFβR1) using lentivirus to further examine the ability of TNFSF11 protein.

RESULTS

This study was the first to uncover TNFSF11 overexpression in the airway and serum of asthmatic human subjects, and the TNFSF11 in serum was closely correlated with lung function. The TNFSF11/TNFRSF11A axis deficiency in Tnfsf11+/- or Tnfrsf11a+/- mice remarkably attenuated the house dust mite (HDM)-induced signal transducer and activator of transcription 3 (STAT3) action and remodeling protein expression. Similarly, the HDM-induced STAT3 action and remodeling protein expression in HBE cells decreased after pretreatment with TNFSF11 or TNFRSF11A shRNA. Meanwhile, the expression of the remodeling proteins induced by TNFSF11 significantly decreased after pretreatment with-stattic (inhibitor of STAT3 phosphorylation) in HBE cells. The STAT3 phosphorylation and remodeling protein expression induced by TNFSF11 obviously decreased after pretreatment with TGFβ1 or TGFβR1 shRNA in HBE cells. The above results also verified that blocking TNFSF11 with denosumab alleviated airway remodeling via the TGFβ1/STAT3 signaling in the humanized HSC-NOG-EXL mice with HDM-induced asthma.

CONCLUSIONS

TGFβ1/STAT3 action was closely correlated with TNFSF11/TNFRSF11A axis-mediated airway remodeling. This study presented a novel strategy that blocks the TNFSF11/TNFRSF11A axis to exert a protective effect against asthma.

Leonotis nepetifolia Transformed Root Extract Reduces Pro-Inflammatory Cytokines and Promotes Tissue Repair In Vitro

Inflammation is closely related to asthma and its defining feature: airway remodeling. The aim of this study was to determine the effects of extracts of normal (NR) and transformed (TR) Leonotis nepetifolia roots on respiratory cells and against the gingival epithelium. Extracts from NR and TR roots were added to lung fibroblast, bronchial epithelial and gingival fibroblast cell lines, in the presence of HRV-16 infection, to determine their impact on inflammation. The expression of inflammatory cytokines (IL-6, IL-1β, GM-CSF and MCAF) as well as total thiol contents were assessed. The TR extract inhibited rhinovirus-induced IL-6 and IL-1β expression in all tested airway cells (p < 0.05). Additionally, the extract decreased GM-CSF expression in bronchial epithelial cells. The tested extracts had positive effects on total thiol content in all tested cell lines. The TR root extract demonstrated wound healing potential. While both tested extracts exhibited anti-inflammatory and antioxidative effects, they were stronger for the TR extract, possibly due to higher concentrations of beneficial metabolites such as phenols and flavonoids. Additionally, wound healing activity was demonstrated for the TR root extract. These results suggest that TR root extract may become a promising therapeutic agent in the future.

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.

Beneficial effects of infrared light-emitting diode in corticosteroid-resistant asthma

Corticosteroid-resistant asthma (CRA) is a severe form of disease and clinically important, since patients do not respond to mainstay corticosteroid therapies. Thus, new therapies are needed. However, a big limiting factor in the understanding of CRA is the existence of different immunological and inflammatory phenotypes, a fact that makes it difficult to reproduce experimentally. Photobiomodulation (PBM) emerges as an alternative therapy based on earlier studies. This study aims to evaluate the effect of PBM using infrared light-emitting diode (ILED) on the development of corticosteroid-resistant asthma. Therefore, groups of rats were sensitized and challenged with ovalbumin plus Freund's adjuvant for the induction of CRA, and treated or not with ILED directly in the respiratory tract on the skin (wavelength 810 nm; power 100 mW; density energy 5 J/cm; total energy 15 J; time 150 s). Our experimental model was capable to induce neutrophilic asthma. Besides that, the corticosteroid treatment did not reverse the lung cell migration as well as the levels of leukotriene B4, and interleukins 17 and 6. The treatment with ILED reduced the lung cell migration; myeloperoxidase activity; mast cell degranulation; and the levels of leukotriene B4, thromboxane B2, prostaglandin E2, tumoral necrosis factor alpha, and interleukins 17 and 6. Still, ILED increased the level of interleukin 10. In conclusion, we showed promisor effects of ILED when irradiated directly in the respiratory tract as adjuvant treatment of corticosteroid-resistant asthma.

Cytokine antibody array-based analysis of IL-37 treatment effects in asthma

Asthma is driven by group 2 innate lymphoid cells, antigen-specific CD4+ T helper type 2 cells and their cytokines such as interleukin (IL)-4, IL-5, IL-13. IL-37 is decreased in asthma and negatively related to Th2 cytokines and other pro-inflammatory cytokines. Our study showed that IL-37 level in asthmatic peripheral blood mononuclear cells was lower than in healthy. Further, IL-37 was negatively correlated with exhaled nitric oxide, asthma control test score, atopy and rhinitis history in asthmatics. Then an OVA-induced asthma mice model treated with rhIL-37 was established. An antibody array was employed to uncover altered cytokines induced by IL-37 in mice lung tissue. 20 proteins differentially expressed after rhIL-37 treatment and five of them were validated in asthmatic peripheral blood mononuclear cells. Consistent with cytokine antibody array, CCL3, CCL4, CCL5 decreased after IL-37 administration. While CXCL9 and CXCL13 were no change. We concluded that IL-37 reduce asthmatic symptoms by inhibit pro-inflammatory cytokine such as CCL3, CCL4, CCL5.

Interleukin-6 promotes ferroptosis in bronchial epithelial cells by inducing reactive oxygen species-dependent lipid peroxidation and disrupting iron homeostasis

Asthma occurs accompanied by the ferroptosis in bronchial epithelial cells, during which Interleukin-6 (IL-6) plays a key role. However, the associations between IL-6, ferroptosis and asthma have not been reported. Bronchial epithelial cells BEAS-2B cells were induced by different concentrations of IL-6 and cell viability was detected by MTT assay. The TBARS production rate was detected by corresponding kit. The expression of oxidative stress-related indexes was detected by ELISA. The Iron Assay Kits detected total iron levels and ferrous ion (Fe²⁺) levels. Labile iron pool assay was used to detect the cell unstable iron pool. The expression of ferroptosis-related proteins was detected by Western blot. To further examine the mechanism of action, ferroptosis inhibitor Ferrostatin 1 (Fer-1), antioxidant NAC, and the iron supplement Fe were added. We found that IL-6 decreased the activity, promoted lipid peroxidation, disrupted iron homeostasis of BEAS-2B cells, and induced iron death in bronchial epithelial BEAS-2B cells. However, pretreatment with Ferrostatin-1 (Fer-1) and antioxidant NAC partially reversed the effect of IL-6 on lipid peroxidation and ferroptosis in BEAS-2B cells, while Fe augmented the effect. Overall, IL-6 promotes ferroptosis in bronchial epithelial cells by inducing reactive oxygen species (ROS)-dependent lipid peroxidation and disrupting iron homeostasis.

Xuefu Zhuyu decoction improves asthma-induced asthenozoospermia based on network pharmacology and in vivo experiment

This study aimed to verify that Xuefu Zhuyu decoction (XFZYD) can improve asthenozoospermia caused by asthma, and explore its potential mechanism. Ovalbumin solution is used to induce asthma rat models. Sperm concentration and motility are used to evaluate semen quality. Immunohistochemistry (IHC), Western blotting and real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR) are used to detect proteins and mRNA related to rat testis tissue. Haematoxylin and eosin (H&E) staining was used to observe changes in testicular tissues. Through network pharmacology, eriodictyol, 18-β-glycyrrhetinic acid, naringenin, chrysin and Hispidulin were prominent active ingredients of XFZYD. We found that XFZYD regulates the expression levels of albumin (ALB), vascular endothelial growth factor A (VEGFA), interleukin 6 (IL-6) protein and mRNA, thereby improving the histopathological morphology of the testis, increasing the concentration and motility of spermatozoa. We suggest that future research can increase the detection of hormones and oxidative stress and other related indicators, so as to conduct more in-depth exploration.