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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.

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 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.