Conciliatory Anti-Allergic Decoction Attenuates Pyroptosis in RSV-Infected Asthmatic Mice and Lipopolysaccharide (LPS)-Induced 16HBE Cells by Inhibiting TLR3/NLRP3/NF-κB/IRF3 Signaling Pathway

Improvement of RSV-Induced Asthma in Mice: A Study Based on Icariin-Mediated PD-1

BACKGROUND

Infection with respiratory syncytial virus (RSV) has the potential to exacerbate asthma by causing prolonged inflammation in the airways. Mounting evidence has revealed the significant involvement of programmed cell death protein-1 (PD-1) in the development of asthma. Although icariin (IC) has shown potential in improving airway remodeling in ovalbumin (OVA)-induced asthma, its impact and underlying mechanisms in cases of asthma aggravated by RSV infection are not thoroughly understood.

OBJECTIVE

To explore the effect of IC on RSV-infected asthmatic mice and the mechanism involving PD-1.

METHODS

A model of asthmatic mice infected with RSV was developed. To evaluate the effects of IC treatment, general behavioral characterization, histopathologic analysis, bronchoalveolar lavage fluid (BALF) analysis, and enzyme-linked immunosorbent assays (ELISA) were performed to assess the frequency of sneezing and nose scratching, the content of OVA-specific IgE, oxidative stress and airway inflammation in mice. Apoptosis was also assessed by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Finally, the expression levels of apoptosis protein, oxidative stress-related protein, and PD-1 were assessed by western blot.

RESULTS

IC significantly ameliorated the sneezing and nose-scratching frequency (p < 0.001) and decreased OVA-specific IgE levels in asthmatic mice infected with RSV (p < 0.01). IC treatment remarkably reduced the infiltration of inflammatory cells around the alveoli and lowered the overall inflammation score. It also notably decreased the levels of inflammatory cytokines interleukin-4 (IL-4), IL-13, and IL-5, and decreased the numbers of neutrophils, eosinophils, and macrophages in the bronchoalveolar lavage fluid (BALF) (p < 0.001). IC ameliorated oxidative stress in RSV-infected asthmatic mice (p < 0.001). In addition, IC reduced apoptosis while increasing PD-1 expression in asthmatic mice infected with RSV (p < 0.001). Interestingly, si-PD-1 significantly reversed IC inhibition of inflammatory cytokines and apoptosis-related proteins, and promoted PD-1 protein expression (p < 0.01). The findings suggested that IC might be effective in alleviating asthma triggered by RSV in mice by regulating the expression of PD-1.

CONCLUSION

IC ameliorated RSV-induced asthma in mice by regulating PD-1 expression, and may hold promise as a potential therapeutic agent for RSV-induced asthma in mice. These findings provide valuable insights into the possibility of using IC as a treatment option for asthma caused by RSV.

TLR3 as an emerging molecule facilitating pyroptosis in the context of rheumatoid arthritis: A study combined bioinformatics and experimental validation

BACKGROUND

Rheumatoid arthritis (RA) is an inflammatory disease of the joints mediated by immune cells. As an immune-related mode of cell death, pyroptosis has yet to be fully understood in RA. This research identified novel pyroptosis-related markers in RA and confirmed its functional significance in RA.

METHODS

Initially, crucial pyroptosis-related genes of RA were identified through GEO database, and biological pathways were determined through enrichment analysis. Then, PPI network, WGCNA and CIBERSORT analysis was utilized to screen hub genes and evaluate immune cell infiltration levels. Finally, validation experiments determined hub genes expression and regulatory roles in RA pathogenesis, and screened potential therapeutic drugs.

RESULTS

A total of 46 DEPRGs in RA were identified, which involved in NOD-like receptor and Toll-like receptor signaling pathway. Further screening revealed 3 crucial hub genes: CCL5, LY96, and TLR3 had significantly increased expression in RA synovial tissue and FLS, which might become diagnostic markers of RA. Analysis of immune infiltration revealed that hub genes exhibited associations with plasma cells, T lymphocytes, and macrophages. Further study on the crucial hub gene TLR3 revealed that knocking down TLR3 significantly inhibited the RA FLS hyperproliferation and pyroptosis, and dexamethasone and doxorubicin, as potential drugs, could treat RA by inhibiting TLR3.

CONCLUSION

Our study indicates that high expression of TLR3 promotes FLS pyroptosis and RA progression, suggesting its potential as both a biomarker and a therapeutic target for RA.

GATA1-activated lncRNA OIP5-AS1 and GAS5 promote pyroptosis to exacerbate asthma through regulating miR-136-5p/LIFR axis

Pyroptosis plays a pivotal role in airway epithelial inflammation during the progression of asthma. This study aimed to explore the influence and mechanisms of opa-interacting protein 5 antisense RNA1 (OIP5-AS1) and growth arrest-specific transcript 5 (GAS5) on pyroptosis in asthmatic models. Pyroptosis was induced in Dermatophagoides pteronyssinus 1 (Der p1)-exposed 16HBE cells and ovalbumin (OVA)-challenged rats. Subsequently, pyroptosis and its related molecular mechanisms were investigated. Our results indicated that GATA1, OIP5-AS1, GAS5, and LIFR were upregulated, while miR-136-5p was downregulated in the patients and experimental models of asthma. OIP5-AS1/GAS5 knockdown repressed NLRP3 inflammasome-mediated pyroptosis in 16HBE cells. Mechanistically, OIP5-AS1/GAS5 sponged miR-136-5p to enhance LIFR expression and subsequently activated NF-κB pathway. OIP5-AS1, GAS5, or LIFR-mediated induction of pyroptosis was abrogated by miR-136-5p mimics or NF-κB inhibitors (BAY11-7082). Finally, GATA1 transcriptionally activated OIP5-AS1/GAS5 to trigger pyroptosis, thereby driving asthma progression in vivo and in vitro. In conclusion, OIP5-AS1/GAS5 transcriptionally activated by GATA1 promoted NLRP3 inflammasome-mediated pyroptosis via the modulation of miR-136-5p/LIFR/NF-κB axis and consequently resulted in airway inflammation in asthma. Our results may provide novel therapeutic strategies for asthma.

Effect of Chloroquine on Type 2 Inflammatory Response in MC903-Induced Atopic Dermatitis Mice

Introduction

Atopic dermatitis (AD) is a chronic, non-infectious inflammatory dermatosis. Chloroquine (CQ) has long been proven to possess anti-inflammatory properties.

Objective

This paper aims to investigate the impact of CQ on type 2 inflammatory response in MC903-induced AD mice.

Methods

An AD mouse model was established via MC903 induction. After CQ treatment, AD mice were intraperitoneally injected with polyinosinic: polycyclic acid [poly (I:C)] or Nigericin. Dermatitis severity was scored, and the thickness of the left ear was measured. The pathological changes in mouse skin tissues were observed by H&E staining. The number of mast cells was counted via TB staining. The content of peripheral blood T-helper 2 (Th2) cells and levels of immunoglobulin E (IgE), thymic stromal-derived lymphopoietin (TSLP), interleukin (IL)-4, IL-13, interferon (IFN)-γ, IL-1β, and IL-18 were assessed by flow cytometry and ELISA. The levels of toll-like receptor 3 (TLR3), NLRP3, ASC, and cleaved caspase-1 proteins in skin tissues were determined by Western blot.

Results

CQ treatment abated dermatitis severity and left ear thickness in AD mice, alleviated skin damage, reduced mast cell number, diminished IgE, TSLP, IL-4, and IL-13 levels, and peripheral blood Th2 cell content, with no significant changes in IFN-γ level. CQ alleviated type 2 inflammatory response in AD mice by inhibiting the activation of TLR3. CQ suppressed NLRP3 inflammasome activation. Activating TLR3/NLRP3 annulled CQ-mediated alleviation on type 2 inflammatory response in AD mice.

Conclusion

CQ alleviated type 2 inflammatory response in AD mice by inhibiting TLR3 activation and NLRP3 inflammasome activation.

Myeloid-specific knockout of Notch-1 inhibits MyD88- and TRIF-mediated TLR signaling pathways by regulating oxidative stress-SHP2 axis, thus restraining aneurysm progression

OBJECTIVE

Notch-1 is a signal regulatory protein with extensive effects in myeloid cells, but its role in aneurysms remains to be fully clarified. In this study, therefore, the aneurysm mouse model with myeloid-specific knockout of Notch-1 was established to observe the role of Notch-1 in aneurysm progression.

METHODS AND RESULTS

The effect of Notch-1 was assessed by pathological staining and Western blotting. It was found that after myeloid-specific knockout of Notch-1 in the aneurysm mouse model, the area of aneurysms and the macrophage infiltration were significantly reduced, the damage to arterial elastic plates was significantly relieved, and the oxidative stress level significantly declined. The results of Western blotting showed that after myeloid-specific knockout of Notch-1, the levels of oxidative stress-related proteins p22 and p47 in aneurysm tissues significantly declined, accompanied by a significant increase in the protein level of Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2). In addition, the levels of phosphorylated myeloid differential protein-88 (MyD88), TIR domain-containing adaptor-inducing interferon-β (TRIF) and nuclear factor-κB (NF-κB), and inflammatory cytokines interferon-γ (IFN-γ), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) also significantly decreased after myeloid-specific knockout of Notch-1. Following myeloid-specific knockout of Notch-1, the phagocytic capacity of macrophages was enhanced by promoting the SHP2 signaling pathway.

CONCLUSION

Notch-1 in monocytes/macrophages can activate the Toll-like receptor (TLR)-mediated inflammatory and stress responses by activating oxidative stress and inhibiting the SHP2 protein expression, thus facilitating aneurysm progression.

Oxidative stress and ROS-mediated cellular events in RSV infection: potential protective roles of antioxidants

Respiratory syncytial virus (RSV), a member of the Pneumoviridae family, can cause severe acute lower respiratory tract infection in infants, young children, immunocompromised individuals and elderly people. RSV is associated with an augmented innate immune response, enhanced secretion of inflammatory cytokines, and necrosis of infected cells. Oxidative stress, which is mainly characterized as an imbalance in the production of reactive oxygen species (ROS) and antioxidant responses, interacts with all the pathophysiologic processes above and is receiving increasing attention in RSV infection. A gradual accumulation of evidence indicates that ROS overproduction plays an important role in the pathogenesis of severe RSV infection and serves as a major factor in pulmonary inflammation and tissue damage. Thus, antioxidants seem to be an effective treatment for severe RSV infection. This article mainly reviews the information on oxidative stress and ROS-mediated cellular events during RSV infection for the first time.

Molecular mechanisms of neuronal death in brain injury after subarachnoid hemorrhage

Subarachnoid haemorrhage (SAH) is a common cerebrovascular disease with high disability and mortality rates worldwide. The pathophysiological mechanisms involved in an aneurysm rupture in SAH are complex and can be divided into early brain injury and delayed brain injury. The initial mechanical insult results in brain tissue and vascular disruption with hemorrhages and neuronal necrosis. Following this, the secondary injury results in diffused cerebral damage in the peri-core area. However, the molecular mechanisms of neuronal death following an aneurysmal SAH are complex and currently unclear. Furthermore, multiple cell death pathways are stimulated during the pathogenesis of brain damage. Notably, particular attention should be devoted to necrosis, apoptosis, autophagy, necroptosis, pyroptosis and ferroptosis. Thus, this review discussed the mechanism of neuronal death and its influence on brain injury after SAH.