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Bronchial asthma poses a considerable burden on both individual patients and public health. Sesamin is a natural lignan that relieves asthma. However, the potential regulatory mechanism has not been fully validated. In this study, we revealed the mechanism of sesamin in inhibiting airway inflammation of asthma. In cockroach extract (CRE)-induced asthmatic mice, sesamin efficiently inhibited inflammatory cell infiltration, expressions of total and CRE-specific IgE in serum, and inflammatory cytokines (including IL-4, 5, 13) in bronchoalveolar lavage fluid. Further study revealed that sesamin inhibited Th2 cells in the mediastinal lymph nodes and spleen, the expression of PTEN-induced putative kinase 1 (PINK1) and Parkin, and apoptosis of lung airway epithelial cells.

Introduction Pterostilbene (Pts) may be used for allergic asthma treatment. The AMPK/Sirt1 and Nrf2/HO‐1 pathways are potential targets for asthma treatement. However, the relationship between Pts and AMPK/Sirt1 and Nrf2/HO‐1 pathways in asthma is unclear. Herein, we aim to explore the pharmacological effects of Pts on oxidative stress and allergic inflammatory response as well as the mechanism involving AMPK/Sirt1 and Nrf2/HO‐1 pathways. Methods Asthma model was established in mice with ovalbumin (OVA). The model mice were treated by different concentrations of Pts. Lung pathological changes were observed through histological staining. In vitro, lipopolysaccharide (LPS)‐stimulated 16HBE cells were treated with Pts. The siAMPKα2, siSirt1 and siNrf2 knockdown, and treatment with compound C, EX‐527 or ML385 were also performed in 16HBE cells. Enzyme‐linked immunosorbent assay was used to detect interleukin‐4 (IL‐4), IL‐13, IL‐5, total and OVA specific immunoglobulin E (IgE), and interferon γ (IFN‐γ). Pneumonography was used to measure the airway hyperreactivity (AHR). Superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) levels were also detected. Immunohistochemistry, Western blot and immunofluorescence were used to measure protein levels. Results Pts significantly attenuated lung inflammatory cell infiltration and goblet cell proliferation. Meanwhile, Pts treatment could reduce IL‐4, IL‐13, IL‐5, and IgE (total and OVA specific) levels in the asthma model mice. However, IFN‐γ in bronchoalveolar lavage fluid was elevated. In addition, Pts reduced AHR. We also found that Pts treatment promoted serum SOD and CAT, and reduced MDA. In vitro results showed that Pts treatment promoted iNOS, TNF‐α, COX‐2, IL‐1β, and IL‐6 expressions in 16HBE cells, prolonged G0/G1 phase of the cell cycle, and resulted in a shortened G2M phase. Moreover, we found that Pts promoted the phosphorylation of AMPK in 16HBE, and meanwhile inhibited the increase of ROS induced by LPS. Additionally, Pts treatment inhibited p‐AMPK, Sirt1, Nrf2 and HO‐1, which in turn leads to the alleviation of AMPK/Sirt1 and Nrf2/HO‐1 pathways. Conclusion Pts alleviated oxidative stress and allergic airway inflammation via regulation of AMPK/Sirt1and Nrf2/HO‐1 signaling pathways., Pts can relieve asthma by suppressing oxidative stress through the AMPK/Sirt1 and Nrf2/HO‐1 signaling pathways. Thus, Pts might be a potential anti‐inflammatory drug for the treatment of asthma.

Bronchial asthma is characterized by chronic airway inflammation, airway hyperresponsiveness, and airway remodeling. MicroRNA (miRNA) has recently been implicated in the pathogenesis of asthma. However, the mechanisms of different miRNAs in asthma are complicated, and the mechanism of miRNA-182-5p in asthma is still unclear. Here, we aim to explore the mechanism of miRNA182-5p in asthma-related airway inflammation. Ovalbumin (OVA)-induced asthma model was established. MiRNA Microarray Analysis was performed to analyze the differentially expressed miRNAs in the asthma model. We found that the expression of miRNA-182-5p was significantly decreased in OVA-induced asthma. In vitro, IL-13 stimulation of BEAS-2B cells resulted in a significant up-regulation of NOX4 (nicotinamide adenine dinucleotide phosphate oxidase 4), accompanied by mitochondrial damage-induced apoptosis, NLRP3 (NOD-like receptor family pyrin domain-containing 3)/IL-1β activation, and reduced miRNA-182-5p. In contrast, overexpression of miRNA-182-5p significantly inhibited epithelial cell apoptosis and NLRP3/IL-1β activation. In addition, we found that miRNA-182-5p could bind to the 3’ untranscripted region of NOX4 mRNA and inhibit epithelial cell inflammation by reducing oxidative stress and mitochondrial damage. In vivo, miRNA-182-5p agomir treatment significantly reduced the percentage of eosinophils in bronchoalveolar lavage fluid, and down-regulated Th2 inflammatory factors, including IL-4, IL-5, and OVA induced IL-13. Meanwhile, miRNA-182-5p agomir reduced the peribronchial inflammatory cell infiltration, goblet cell proliferation and collagen deposition. In summary, targeting miRNA-182-5p may provide a new strategy for the treatment of asthma.

This study is to investigate the inhibitory effects and mechanisms of DEK‐targeting aptamer (DTA‐64) on epithelial mesenchymaltransition (EMT)‐mediated airway remodelling in mice and human bronchial epithelial cell line BEAS‐2B. In the ovalbumin (OVA)‐induced asthmatic mice, DTA‐64 significantly reduced the infiltration of eosinophils and neutrophils in lung tissue, attenuated the airway resistance and the proliferation of goblet cells. In addition, DTA‐64 reduced collagen deposition, transforming growth factor 1 (TGF‐β1) level in BALF and IgE levels in serum, balanced Th1/Th2/Th17 ratio, and decreased mesenchymal proteins (vimentin and α‐SMA), as well as weekend matrix metalloproteinases (MMP‐2 and MMP‐9) and NF‐κB p65 activity. In the in vitro experiments, we used TGF‐β1 to induce EMT in the human epithelial cell line BEAS‐2B. DEK overexpression (ovDEK) or silencing (shDEK) up‐regulated or down‐regulated TGF‐β1 expression, respectively, on the contrary, TGF‐β1 exposure had no effect on DEK expression. Furthermore, ovDEK and TGF‐β1 synergistically promoted EMT, whereas shDEK significantly reduced mesenchymal markers and increased epithelial markers, thus inhibiting EMT. Additionally, shDEK inhibited key proteins in TGF‐β1‐mediated signalling pathways, including Smad2/3, Smad4, p38 MAPK, ERK1/2, JNK and PI3K/AKT/mTOR. In conclusion, the effects of DTA‐64 against EMT of asthmatic mice and BEAS‐2B might partially be achieved through suppressing TGF‐β1/Smad, MAPK and PI3K signalling pathways. DTA‐64 may be a new therapeutic option for the management of airway remodelling in asthma patients.

We investigated the regulatory role of miR-181b-5p in neutrophilic asthma and its mechanisms by targeting DEK. DEK, matrix metalloproteinase (MMP)-2, and MMP-9 were overexpressed and the miR-181b-5p was decreased in mice with neutrophilic asthma. DEK was a direct target of miR-181b-5p. In mouse model, miR-181b-5p agomir had an inhibitory effect on airway inflammation and remodeling. miR-181b-5p inhibited DEK/p-GSK-3β

MicroRNAs (miRNAs) can participate in airway remodeling by regulating immune molecule expression. Here, we aimed to identify the differential miRNAs involved in airway remodeling. Airway remodeling was induced by ovalbumin in female BALB/C mice. The differentially expressed miRNAs were screened with microarray. GO (Gene Ontology) and KEGG enrichment analysis was performed. The miRNA target gene network and miRNA target pathway network were constructed. Verification with real-time PCR and Western blot was performed. We identified 63 differentially expressed miRNAs (50 up-regulated and 13 down-regulated) in the lungs of ovalbumin-induced airway remodeling mice. Real-time PCR confirmed that 3 miRNAs (mmu-miR-1931, mmu-miR-712-5p, and mmu-miR-770-5p) were significantly up-regulated, and 4 miRNAs (mmu-miR-128-3p, mmu-miR-182-5p, mmu-miR-130b-3p, and mmu-miR-20b-5p) were significantly down-regulated. The miRNA target gene network analysis identified key mRNAs in the airway remodeling, such as Tnrc6b (trinucleotide repeat containing adaptor 6B), Sesn3 (sestrin 3), Baz2a(bromodomain adjacent to zinc finger domain 2a), and Cux1 (cut like homeobox 1). The miRNA target pathway network showed that the signal pathways such as MAPK (mitogen-activated protein kinase), PI3K/Akt (phosphoinositide 3-Kinase/protein kinase B), p53 (protein 53), and mTOR (mammalian target of rapamycin) were closely related to airway remodeling in asthma. Collectively, differential miRNAs involved in airway remodeling (such as mmu-miR-1931, mmu-miR-712-5p, mmu-miR-770-5p, mmu-miR-128-3p mmu-miR-182-5p, and mmu-miR-130b-3p) as well as their target genes (such as Tnrc6b, Sesn3, Baz2a, and Cux1) and pathways (such as MAPK, PI3K/Akt, p53, mTOR pathways) have been identified. Our findings may help to further understand the pathogenesis of airway remodeling.

Neutrophils, classified as professional phagocytes, are crucial in killing bacteria and preventing inflammation. When studying the roles of neutrophils in the development of the septic peritonitis induced by E. coli, we noticed some of the larger cells existed among peritoneal lavage fluid cells (PLCs). Besides the large size, their nuclei are segmented and flat, and squeezed to the marginal zone of the inner membrane. The cells, therefore, were designated as E. coli induced larger neutrophils (e-Neus). Further studies showed that, the e-Neus were ly6G positive, indicating the e-Neus were a type of neutrophils. The enlarged cell size and marginal nucleus of the e-Neus were caused by engulfing abundant of E. coli, marking the active participation of the e-Neus in clearance of E. coli. Functionally, the e-Neus generated reactive oxygen species (ROS) and IL-10. Furthermore, the occurrence and accumulation of the e-Neus were closely correlated with the severity of septic peritonitis and mortality of the mice. Overall, the e-Neus presented here may enrich the understandings on neutrophil transitions in response to various insults, and could be used to evaluate the severity of septic peritonitis induced by E. coli.

We investigated whether Panax notoginseng saponin (PNS-R1) attenuates allergic rhinitis (AR) through AMPK/Drp1-mediated mitochondrial fission. AR model was established in mice by Ovalbumin (OVA). In vitro, human nasal epithelial cells (HNEpCs) were stimulated using recombinant human interleukin 13 (IL-13). PNS-R1 was administrated in vivo and in vitro. Then, HE staining of nasal tissue, ELISA detection of immunoglobulin E (IgE) and proinflammatory cytokine levels in serum and nasal lavage fluid, flow cytometry analysis of Th1/Th2 ratio and apoptosis, TUNEL staining, Western blot, detection of reactive oxygen species (ROS) and mitochondrial ROS, immunofluorescence analysis of Tom20 and mitochondrial fission protein Drp1 co-localization, and mitochondrial membrane potential detection, were performed. PNS-R1 attenuated allergic symptoms in AR mice, decreased OVA-specific IgE, IL-4, IL-6, IL-8, IL-13, and TNF-α levels, and restored the Th1/Th2 imbalance. Meanwhile, we found that PNS-R1 treatment significantly reduced apoptosis, ROS production, and co-localization of Tom20 and Drp1 in the nasal epithelium of AR mice. In vitro, we found that PNS-R1 upregulated mitochondrial membrane potential and reduced ROS and mitochondrial ROS production as well as Cleaved-caspase-3/9, Bax, Cyt-c, Apaf-1 expression and mitochondrial fission. Mechanistically, we found that PNS-R1 downregulated Drp1 phosphorylation (Ser 616) and Drp1 translocation in an AMPK-dependent manner, promoted MFN2 expression, and reduced TXNIP, NLRP3, Caspase-1, and IL-1β expression. PNS-R1 may protect mitochondrial integrity by inhibiting AMPK/Drp1 and TXNIP/NLRP3 signaling pathway, thereby alleviating AR symptoms in mice. PNS-R1 may have great potential as a therapeutic agent for AR.

Lymphocyte activation gene-3 (LAG3) is a transmembrane protein expressed on activated T cells and delivers inhibitory signals to render the T cells unable to effectively help B cells to produce antibodies to microbes and vaccines. Presumably, antagonizing LAG3 could enhance the antibody responses to vaccines, and LAG3 antagonists could facilitate vaccines to induce vigorous antibody responses. In this study, we designed a LAG3-interfering antisense oligonucleotide, designated as LIO-1. The LIO-1 is complementary to an identical region shared in human and mouse LAG3 mRNA. We demonstrated that LIO-1 induced the degradation of LAG3 mRNA in immune cells, decreased the LAG3 expression on CD4+ T cells, maintained the prolonged proliferation and promoted the activation of antigen-specific CD4+ T cells, and increased the production of IFN-γ, IL-2, and IL-6 in the antigen re-stimulated immune cells. In addition, we found that LIO-1 enhanced the antibody responses induced by ISA35-formulated recombinant antigen vaccine or ISA35-formulated inactivated influenza virus vaccines in mice. Thus, the LIO-1, a nucleic acid LAG3 antagonist, could facilitate vaccines to induce vigorous antibody responses and has the possibility to be used as a novel adjuvant.