Qi Hou

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous disease characterized by persistent airflow limitation but still lacking effective treatments. Perilla frutescens (L.) Britt., an important traditional medicinal plant with excellent antioxidant and anti-inflammatory properties, is widely used for the treatment of respiratory disease in China. However, its protective activity and mechanism against COPD airway inflammation have not been fully studied. Here, the anti-inflammatory effects of the PLE were investigated, and its underlying mechanisms were then elucidated. The presented results suggested a notable effect of the PLE on airway inflammation of COPD, by significantly ameliorating inflammatory cell infiltration in lung tissue, lessening leukocytes (lymphocytes, neutrophils, and macrophages) and inflammatory mediators (interleukin 4 (IL-4), IL-6, IL-17A, interferon γ (IFN-γ), and tumor necrosis factor α (TNF-α)) in the bronchoalveolar lavage fluid (BALF) of cigarette smoke (CS)/lipopolysaccharide (LPS)-induced COPD mice in vivo and inhibiting the production of inflammatory factors (nitric oxide (NO), IL-6, and TNF-α) and intracellular reactive oxygen species (ROS) in LPS-stimulated RAW264.7 cells in vitro. For further extent, PLE treatment significantly suppressed the expression and phosphorylation of TLR4, Syk, PKC, and NF-κB p65 in vivo and their mRNA in vitro. Subsequently, by co-treating with their inhibitors in vitro, its potential mechanism via TLR4/Syk/PKC/NF-κB p65 signals was disclosed. In summary, the obtained results indicated a noteworthy effective activity of the PLE on COPD inflammation, and partly, the TLR4/Syk/PKC/NF-κB p65 axis might be the potential mechanism.

Introduction: Asthma–chronic obstructive pulmonary (COPD) overlap (ACO) coexists with asthma and COPD syndrome characteristics, with more frequent exacerbations, heavier disease burden, higher medical utilization, and even lower quality of life. However, the ACO standard medications supported by evidence-based medicine have not yet appeared. Methods: By using an ACO mouse model established previously and LPS-stimulated RAW264.7 macrophages in vitro, a potential therapeutic candidate, EAPP-2, was screened from derivatives of 3-arylbenzofuran, and its effect and mechanism on ACO inflammation were evaluated. Results: EAPP-2 significantly alleviated airway inflammation in ACO mice and also inhibited the inflammatory reactions in LPS-induced RAW264.7 macrophages in vitro. Furthermore, EAPP-2 significantly inhibited the expression and phosphorylation of spleen tyrosine kinase (Syk), a common target regulating both eosinophils and neutrophils inflammation. In addition to this, EAPP-2 significantly down-regulates the expression of NF-κB, p-NF-κB, and NLRP3 in vivo and in vitro. Moreover, by using specific inhibitors in vitro, it was validated that EAPP-2 targeted on Syk and then regulated its downstream NF-κB and NLRP3. Conclusion: EAPP-2 is shown to be a potentially useful therapeutic candidate for ACO, and its mechanism is at least partially achieved by targeting on Syk and then inhibiting NF-κB or NLRP3. Moreover, this study suggests that Syk may be a potentially effective target for ACO therapy.

Brusatol derivative-34 (Bru-34), a derivative of brusatol, has been shown significantly anti-inflammatory activity in mice in our previously work. However, to our knowledge, there were very limited studies on how Bru-34 affected airway inflammation. Thus, in this present study, the effects and potential mechanisms of Bru-34 on allergic airway inflammation were examined both in vivo and in vitro. The results showed that Bru-34 attenuated the allergic airway inflammation in mice, with significant decreasing of the inflammatory cells and mediators in bronchoalveolar lavage fluids and attenuation of the histopathological alterations in the lung tissues. In addition, Bru-34 significantly inhibited the release of inflammatory cytokines in antigen induced rat basophilic leukemia -2H3 (RBL-2H3) cells. What’s more, Bru-34 significantly decreased the expression of spleen tyrosine kinase (Syk), p-Syk, cytoplasmic phospholipase A2 (cPLA2), p-cPLA2, nuclear factor-κB (NF-κB) and p-NF-κB both in allergic mice lung tissue and antigen induced RBL-2H3 cells. Furthermore, the collaborative effects of Bru-34 with inhibitors against Syk, cPLA2, and NF-κB, showed that Syk was an important target of Bru-34, and cPLA2 and NF-κB played important roles in the coordinated inflammatory response. In conclusion, Bru-34 could significantly modulate the allergic airway inflammation, and its potential mechanism was revealed at least partially via down-regulating of Syk-cPLA2 -NF-κB signaling.

Asthma–chronic obstructive pulmonary disease (COPD) overlap (ACO) is a severe clinical syndrome characterized to describe patients with both asthma and COPD clinical characteristics, which has posed a serious threat to patients’ quality of life and life safety. However, there are many difficulties and uncertainties in its diagnosis and treatment in clinic; especially, its animal model has not been fully and thoroughly established, and the evaluation of therapeutic drugs is still in its infancy. Here, we used ovalbumin (OVA), lipopolysaccharide (LPS), and smoke costimulation to establish an ACO mouse model and then used RNA-seq technology to detect gene expression in mouse lung tissue. The results showed that ACO mice showed an overlap syndrome of asthma and COPD in lung histological changes and the levels of inflammatory cytokines in bronchoalveolar lavage fluid. The RNA-seq analysis results showed that 6,324 differentially expressed genes (DEGs) were screened between the ACO group and the control group, of which 2,717 (42.7%) were downregulated, and 3,607 (57.3%) were upregulated. Metascape analysis results showed that in the ACO model we established, due to the damage of the respiratory system, the accumulated diseased tissue involves lung, spleen, blood, bone marrow, thymus, etc. It has certain characteristics of pneumonia, pulmonary fibrosis, and chronic obstructive airway disease, lung tumors, rheumatoid arthritis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis showed that DEGs were enriched in inflammation, immune system activation and imbalance, cell proliferation, and adhesion migration, and the upstream signaling pathways of inflammation were mainly affected by HLA-DRA, SYK, CTLA4, VAV1, NRAS, and JAK3. In short, our research established a mouse model that can better simulate the clinicopathological characteristics of ACO and suggested the foundations in elucidating the molecular mechanisms for pulmonary inflammation and fibrosis in ACO. This work may help further research and contribute substantially to prevention and clinical treatment of ACO in the future.

Perilla frutescens (L.) Britton is a classic herbal plant used widely against asthma in China. But its mechanism of beneficial effect remains undermined. In the study, the antiallergic asthma effects of Perilla leaf extract (PLE) were investigated, and the underlying mechanism was also explored. Results showed that PLE treatment significantly attenuated airway inflammation in OVA‐induced asthma mice, by ameliorating lung pathological changes, inhibiting recruitment of inflammatory cells in lung tissues and bronchoalveolar lavage fluid (BALF), decreasing the production of inflammatory cytokines in the BALF, and reducing the level of immunoglobulin in serum. PLE treatment suppressed inflammatory response in antigen‐induced rat basophilic leukemia 2H3 (RBL‐2H3) cells as well as in OVA‐induced human peripheral blood mononuclear cells (PBMCs). Furthermore, PLE markedly inhibited the expression and phosphorylation of Syk, NF‐κB, PKC, and cPLA₂ both in vivo and in vitro. By cotreating with inhibitors (BAY61‐3606, Rottlerin, BAY11‐7082, and arachidonyl trifluoromethyl ketone) in vitro, results revealed that PLE’s antiallergic inflammatory effects were associated with the inhibition of Syk and its downstream signals NF‐κB, PKC, and cPLA₂. Collectively, the present results suggested that PLE could attenuate allergic inflammation, and its mechanism might be partly mediated through inhibiting the Syk pathway.

Background: Perilla frutescens (L.) Britt., a classic medicinal plant, has been demonstrated to have anti-inflammatory and anti-allergic effects in asthma. Perilla leaves extract (PLE) exerted significant therapeutic effect against allergic asthma inflammation through Syk inhibition. But the active chemical ingredients from PLE are complex and unclear, it is difficult to fully elucidate its pharmacological mechanisms. Methods: A method was established for rapid screening and characterization of active ingredients from PLE that targeted Syk, with which three potential active ingredients were identified. By using OVA-induced allergic asthma mouse model in vivo, OVA-induced human PBMCs inflammation model and DNP-IgE/BSA-induced RBL-2H3 cells model in vitro, the effects and mechanisms of PLE and its active components were evaluated. Results: Using Syk-affinity screening method, roseoside (RosS), vicenin-2 (Vic-2) and rosmarinic acid (RosA) were identified from PLE. In vitro, PLE and its ingredients showed significant inhibitory activities against Syk, with their mixture (Mix, prepared by RosS, Vic-2 and RosA in accordance with their ratio in Syk-conjugated beads bound fraction) showing a stronger inhibitory activity. RosS, Vic-2 and RosA also showed significant effects on allergic asthma, and a synergistic effect of Mix was observed. Moreover, treatment with PLE, RosS, Vic-2, RosA, and Mix significantly inhibited the expression and phosphorylation of Syk, PKC, NF-κB p65, and cPLA₂ in allergic mice lung tissue and in RBL-2H3 cells. Conclusion: PLE may alleviate allergic airway inflammation partly through the multiple components synergistic targeting on Syk and its downstream inflammatory pathway.

The low‐grade, chronic inflammation initiated by TLR4‐triggered innate immune responses has a central role on early osteoarthritis. Amurensin H is a resveratrol dimer with anti‐inflammatory and anti‐apoptotic effects, while its effects on TLR‐4 signals to inhibit osteoarthritis are still unclear. In the present study, treatment with amurensin H for 2 weeks in monosodium iodoacetate‐induced mice significantly slows down cartilage degeneration and inflammation using macroscopic evaluation, haematoxylin and eosin (HE) staining and micro‐magnetic resonance imaging. In IL‐1β‐stimulated rat chondrocytes, amurensin H suppresses the production of inflammatory mediators including nitric oxide, IL‐6, IL‐17, PGE2 and TNF‐α using Greiss and ELISA assay. Amurensin H inhibits matrix degradation via decreasing levels of MMP‐9 and MMP‐13 using Western blot assay, promotes synthesis of type II collagen and glycosaminoglycan using immunostaining and safranin O staining, respectively. Amurensin H inhibits intracellular and mitochondrial reactive oxygen species (ROS) generation, and mitochondrial membrane depolarization using DCFH‐DA, MitoSOX Red and JC‐1 assay as well. IL‐1β stimulates TLR4 activation and Syk phosphorylation in chondrocytes, while amurensin H inhibits TLR4/Syk signals and downstream p65 phosphorylation and translocation in a time and dose‐dependent manner. Together, these results suggest that amurensin H exerts chondroprotective effects by attenuating oxidative stress, inflammation and matrix degradation via the TLR4/Syk/NF‐κB pathway.

Background. Henoch–Schönlein purpura nephritis (HSPN) is the principal cause of morbidity and mortality in Henoch–Schönlein purpura (HSP). However, there is no absolute consensus for the best management of severe HSPN till now. Qingzixiaoban Granule (QZXB GR), a traditional Chinese medicine formula, has been applied to treat HSP in clinical in China. However, the therapeutic effects and potential mechanism of QZXB GR on HSPN is still unknown.Methods. A Gliadin plus Indian Ink-induced HSPN mice model was established. Renal histopathologic changes and the subcutaneous hemorrhage on left legs were assessed. Hematuria and proteinuria were determined using hemocytometer and bicinchoninic acid assay, respectively. The serum circular immune complex and interleukin-6 were quantified by ELISA. Using blood biochemical analyzer, the renal biochemical parameters, including serum total protein, albumin, creatinine, and blood urea nitrogen, were measured. The deposition of immune complex in renal tissues and the lymphocyte subsets in peripheral blood and spleen was investigated by immunohistochemistry and flow cytometry.Results. QZXB GR treatment significantly ameliorated renal injury in HSPN mice, by attenuating renal histopathological changes, reducing subcutaneous hemorrhage, decreasing proteinuria/hematuria, regulating renal biochemical parameters, and inhibiting the release of serum interleukin-6. Furthermore, QZXB GR treatment significantly decreased the level of serum circular immune complex, decreased immune complex IgA and IgG deposition in renal tissue, and suppressed Th2 immunodeviation.Conclusion. QZXB GR could prevent renal injury in HSPN mice, and its renoprotective mechanism might be exerted partly through suppressing immune complexes deposition and Th2 immune deviation.

Amurensin H, a resveratrol dimer derived from Vitis amurensis Rupr, has several biological effects, including anti-inflammatory and antioxidant activities. Studies have found that amurensin H attenuated asthma-like allergic airway inflammation. However, its protective activity on chronic obstructive pulmonary disease (COPD) airway inflammation is not fully explored. The present study used a lipopolysaccharide (LPS)/cigarette smoke–induced mice model and an LPS-stimulated THP-1–derived macrophages model to measure the lung tissue’s morphology changes. The results showed that amurensin H ameliorated the histological inflammatory alterations in the lung tissues, leading to a decrease in the expression of interleukin 6 (IL-6), IL-17A, tumor necrosis factor α (TNF-α), and interferon γ in bronchoalveolar lavage fluid. Amurensin H also significantly inhibited the release of IL-1β, IL-6, IL-8, and TNF-α in LPS-stimulated THP-1–derived macrophages. Furthermore, amurensin H markedly inhibited the expressions of p-Syk, nuclear factor κB (NF-κB), and p-NF-κB both in vivo and in vitro. Results from cotreatment with Syk inhibitor BAY61-3606 and NF-κB inhibitor BAY11-7082 in vitro revealed that amurensin H’s protective effect against airway inflammation could be due partly to the inhibition of the Syk/NF-κB pathway. These findings suggest that amurensin H shows therapeutic effects on COPD airway inflammation, and inhibiting the Syk/NF-κB pathway might be part of its underlying mechanisms.