Dexmedetomidine Alleviates Hyperoxia-Induced Acute Lung Injury via Inhibiting NLRP3 Inflammasome Activation

Background/Aims: Dexmedetomidine (Dex), a specific agonist of α2-adrenoceptor, has been reported to have extensive pharmacological effects. In this study, we focused on the protective effect of Dex on hyperoxia-induced acute lung injury and further explored its possible molecular mechanisms. Methods: The model of hyperoxia-induced acute lung injury was established by continuous inhalation of oxygen (FiO2= 0.90) for 7 d in neonatal rats in vivo. The in vitro experiments were carried out in LPS/ATP or hyperoxia-treated RAW264.7 cells. ELISA, western blot, TUNEL staining, and immunohistochemistry staining assays were performed and the commercial kits were used to assess the beneficial effect of Dex on hyperoxia-induced acute lung injury. Results: According to our results, Dex treatment attenuated hyperoxia-induced acute lung injury via decreasing the lung wet/dry(W/D) weight ratio and mitigating pathomorphologic changes. Moreover, the oxidative stress injury, inflammatory reaction, and apoptosis in lung epithelial cells were inhibited by Dex treatment. In addition, the activation of NLRP3 inflammasome was restrained by Dex both in lung tissue in vivo and RAW264.7 cells in vitro. Conclusion: These data provide evidence that Dex may ameliorate hyperoxia-induced acute lung injury, which suggests a potential clinical application of Dex in long-term supplemental oxygen therapy.

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Heat Shock Preconditioning Mesenchymal Stem Cells Attenuate Acute Lung Injury via Reducing NLRP3 Inflammasome Activation in Macrophages

10.21203/rs.3.rs-139954/v1 ◽

2021 ◽

Author(s):

Haijin Lv ◽

Xiaofeng Yuan ◽

Jiebin Zhang ◽

Tongyu Lu ◽

Jia Yao ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Acute Lung Injury ◽

Lung Injury ◽

Nlrp3 Inflammasome ◽

Inflammasome Activation ◽

Pathological Changes ◽

Nlrp3 Inflammasome Activation

Abstract Objectives: Acute lung injury (ALI) remains one of the common causes of morbidity and mortality worldwide, so far, without any effective therapeutic approach. Previous researches have revealed that topical administration of umbilical cord-derived mesenchymal stem cells (UC-MSCs) can attenuate pathological changes in experimental acute lung injury. Heat shock (HS) pretreatment has been identified as a method to enhance survival and function of cells. The present study aimed to assess whether HS-pretreated mesenchymal stem cells (MSCs) could strengthen the immunomodulation and recovery from ALI. Materials and Methods: HS pretreatment was defined 42℃ for 1h, the changes of biological characteristics and the secreted functions were detected. In the mouse model of ALI, we intranasally dripped the pretreated UC-MSCs in vivo, confirmed their therapeutic effects and detected the phenotypes of macrophages in bronchoalveolar lavage fluid (BALF). To elucidate their mechanisms, we co-cultured the pretreated UC-MSCs with macrophages in vitro, and the expression levels of inflammasome-related proteins in macrophages were assessed. Finally, Apoptozole was used for further determine the role of HSP70 in HS-pretreated UC-MSCs-based therapy. Results: The data showed that UC-MSCs did not represented significant changes in viability and biological characterizations after received HS pretreatment. Administration of HS-pretreated UC-MSCs into the ALI model, improved pathological changes and lung damage-related indexes, reduced of the levels of pro-inflammatory cytokines and modulated the balance of M1/M2. Mechanistically, both in vivo and in vitro studies demonstrated that HS pretreatment enhanced the protein level of HSP70 in UC-MSCs and subsequently upregulated the synthesis and secretion of PGE2, which negatively modulated the NLRP3 inflammasome activation of alveolar macrophages. And these effects was partially reversed by Apoptozole. Conclusion: HS pretreatment can strengthen the beneficial effects of UC-MSCs on inhibiting NLRP3 inflammasome activation of macrophages in ALI. The mechanism may be contributed to the upregulated expression of HSP70 to further induce PGE2 synthesis and secretion.

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Heat shock preconditioning mesenchymal stem cells attenuate acute lung injury via reducing NLRP3 inflammasome activation in macrophages

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02328-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Haijin Lv ◽

Xiaofeng Yuan ◽

Jiebin Zhang ◽

Tongyu Lu ◽

Jia Yao ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Acute Lung Injury ◽

Lung Injury ◽

Nlrp3 Inflammasome ◽

Inflammasome Activation ◽

Pathological Changes ◽

Nlrp3 Inflammasome Activation

Abstract Objectives Acute lung injury (ALI) remains a common cause of morbidity and mortality worldwide, and to date, there is no effective treatment for ALI. Previous studies have revealed that topical administration of mesenchymal stem cells (MSCs) can attenuate the pathological changes in experimental acute lung injury. Heat shock (HS) pretreatment has been identified as a method to enhance the survival and function of cells. The present study aimed to assess whether HS-pretreated MSCs could enhance immunomodulation and recovery from ALI. Materials and methods HS pretreatment was performed at 42 °C for 1 h, and changes in biological characteristics and secretion functions were detected. In an in vivo mouse model of ALI, we intranasally administered pretreated umbilical cord-derived MSCs (UC-MSCs), confirmed their therapeutic effects, and detected the phenotypes of the macrophages in bronchoalveolar lavage fluid (BALF). To elucidate the underlying mechanisms, we cocultured pretreated UC-MSCs with macrophages in vitro, and the expression levels of inflammasome-related proteins in the macrophages were assessed. Results The data showed that UC-MSCs did not exhibit significant changes in viability or biological characteristics after HS pretreatment. The administration of HS-pretreated UC-MSCs to the ALI model improved the pathological changes and lung damage-related indexes, reduced the proinflammatory cytokine levels, and modulated the M1/M2 macrophage balance. Mechanistically, both the in vivo and in vitro studies demonstrated that HS pretreatment enhanced the protein level of HSP70 in UC-MSCs, which negatively modulated NLR family pyrin domain containing 3 (NLRP3) inflammasome activation in alveolar macrophages. These effects were partially reversed by knocking down HSP70 expression. Conclusion HS pretreatment can enhance the beneficial effects of UC-MSCs in inhibiting NLRP3 inflammasome activation in macrophages during ALI. The mechanism may be related to the upregulated expression of HSP70. Graphical abstract

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Wolf–Hirschhorn syndrome candidate 1 facilitates alveolar macrophage pyroptosis in sepsis-induced acute lung injury through NEK7-mediated NLRP3 inflammasome activation

Innate Immunity ◽

10.1177/17534259211035426 ◽

2021 ◽

pp. 175342592110354

Author(s):

Caixia Liu ◽

Benlong Cai ◽

Dan Li ◽

Yuan Yao

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Alveolar Macrophage ◽

Cancer Progression ◽

Nlrp3 Inflammasome ◽

Inflammasome Activation ◽

Nlrp3 Inflammasome Activation ◽

Incidence And Mortality

Sepsis is a complex clinical syndrome with high incidence and mortality. Acute lung injury (ALI) is a common complication of sepsis. At present, there is no effective therapeutic strategy to treat ALI. The SET domain–containing histone methyltransferase Wolf–Hirschhorn syndrome candidate 1 (WHSC1) regulates cancer progression, while its role in sepsis-induced ALI remains unclear. Thus, this study aimed to study the effect of WHSC1 on sepsis-induced ALI and to explore the potential mechanism of action. In the study, LPS treatment induced lung injury. WHSC1 was highly expressed in LPS-induced ALI. Knockdown of WHSC1 attenuated LPS-induced ALI and pyroptosis in vivo. Besides, knockdown of WHSC1 attenuated LPS-induced alveolar macrophage pyroptosis in vitro. Furthermore, NIMA-related kinase-7 (NEK7) expression could be regulated by WHSC1, and NEK7 bound to NLRP3 in alveolar macrophages. Moreover, WHSC1 regulated alveolar macrophage pyroptosis through modulating NEK7-mediated NLRP3 inflammasome activation. In conclusion, WHSC1 was highly expressed in LPS-induced ALI. WHSC1 facilitated alveolar macrophage pyroptosis in sepsis-induced ALI through NEK7-mediated NLRP3 inflammasome activation. WHSC1 may be a valuable target for the therapy of sepsis-induced ALI.

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Anemoside B4 Protects against Acute Lung Injury by Attenuating Inflammation through Blocking NLRP3 Inflammasome Activation and TLR4 Dimerization

Journal of Immunology Research ◽

10.1155/2020/7502301 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Renyikun Yuan ◽

Jia He ◽

Liting Huang ◽

Li-Jun Du ◽

Hongwei Gao ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Protective Effect ◽

Inflammatory Cytokines ◽

Nlrp3 Inflammasome ◽

Inflammasome Activation ◽

Macrophage Cells ◽

Nlrp3 Inflammasome Activation ◽

Anti Inflammatory

Acute lung injury (ALI) is an acute inflammatory process in the lung parenchyma. Anemoside B4 (B4) was isolated from Pulsatilla, a plant-based drug against inflammation and commonly applied in traditional Chinese medicine. However, the anti-inflammatory effect and the mechanisms of B4 are not clear. In this study, we explored the potential mechanisms and anti-inflammatory activity of B4 both in vitro and in vivo. The results indicated that B4 suppressed the expression of iNOS, COX-2, NLRP3, caspase-1, and IL-1β. The ELISA assay results showed that B4 significantly restrained the release of inflammatory cytokines like TNF-α, IL-6, and IL-1β in macrophage cells. In addition, B4 rescued mitochondrial membrane potential (MMP) loss in (lipopolysaccharide) LPS plus ATP stimulated macrophage cells. Co-IP and molecular docking results illustrated that B4 disrupted the dimerization of TLR4. For in vivo results, B4 exhibited a protective effect on LPS and bleomycin- (BLM-) induced ALI in mice through suppressing the lesions of lung tissues, the release of inflammatory cytokines, and the levels of white blood cells, neutrophils, and lymphoid cells in the blood. Collectively, B4 has a protective effect on ALI via blocking TLR4 dimerization and NLRP3 inflammasome activation, suggesting that B4 is a potential agent for the treatment of ALI.

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NLRP3 Inflammasome Activation Attenuates Neuronal Apoptosis by Upregulating Autophagy through AMPK/Beclin-1 Pathway after Intracerebral Hemorrhage with Ventricular Extension in Rats

10.21203/rs.3.rs-203453/v1 ◽

2021 ◽

Author(s):

Zhaoqi Zhang ◽

Peiwen Guo ◽

Zhengcai Jia ◽

Tunan Chen ◽

Hua Feng

Keyword(s):

Intracerebral Hemorrhage ◽

Nlrp3 Inflammasome ◽

Neuronal Apoptosis ◽

Specific Inhibitor ◽

Beclin 1 ◽

Tunel Staining ◽

Inflammasome Activation ◽

Sprague Dawley

Abstract BackgroundIn brain, NLRP3 inflammasome, mainly derived from macrophage/microglia, is involved in proinflammatory and neurodeficits after hemorrhage, and autophagy is vital for neuronal homeostasis and functions. Accumulating evidence suggested that NLRP3 inflammasome and autophagy played an important role in intracerebral hemorrhage (ICH). Thus, this study was designed to further explore the pathogenesis of neurodeficits after in posthemorrhagic hydrocephalus.MethodsAutologous blood injection model was induced to mimic ICH with ventricular extension (ICH-IVH) in Sprague-Dawley rats. To elucidate the underlying mechanism, the NLRP3 inflammasome inhibitor MCC950 was administered abdominally at 1 h after ICH-IVH. Magnetic resonance imaging, neurobehavioral tests, immunofluorescence, western blotting, Fluoro-Jade C- staining, Tunel staining, and Quantitative RNA Sequencing were performed.ResultsIn the acute phase of ICH-IVH, both the expression of NLRP3 inflammasome and the autophagy of neurons were upregulated. The activated NLRP3 in macrophage/microglia promoted the release of IL-1β to extracellular, which contributed to excessive autophagy, leading to neurons apoptosis both in vivo and in vitro. AMPK/Beclin-1 pathway played an important role in NLRP3-related neurons autophagy. Using MCC950(NLRP3 inflammasome specific inhibitor) treatment after ICH-IVH significantly reduced ventricles dilation, improved neurofunction, down-regulated the release of IL-1β, and alleviated neuroinflammation and excessive autophagy.ConclusionsOur finding demonstrated that NLRP3 inflammasome activated in microglia/macrophage aggravated neurological outcomes and neuronal apoptosis by upregulating autophagy after ICH-IVH, which was partly mediated by the AMPK/Beclin-1 pathway. Therefore, inhibiting the activation of NLRP3 may be a potential therapeutic strategy for the neurodeficits of ICH-IVH patients.

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Calycosin Alleviates Doxorubicin-Induced Cardiotoxicity and Pyroptosis by Inhibiting NLRP3 Inflammasome Activation

Oxidative Medicine and Cellular Longevity ◽

10.1155/2022/1733834 ◽

2022 ◽

Vol 2022 ◽

pp. 1-15

Author(s):

Lei Zhang ◽

Cundong Fan ◽

Hua-Chen Jiao ◽

Qian Zhang ◽

Yue-Hua Jiang ◽

...

Keyword(s):

Nlrp3 Inflammasome ◽

Cardiac Injury ◽

H9c2 Cell ◽

Inflammasome Activation ◽

Dependent Manner ◽

H9c2 Cells ◽

Stress Injury ◽

Nlrp3 Inflammasome Activation

Calycosin (CAL) is the main active component present in Astragalus and reportedly possesses diverse pharmacological properties. However, the cardioprotective effect and underlying mechanism of CAL against doxorubicin- (DOX-) induced cardiotoxicity need to be comprehensively examined. Herein, we aimed to investigate whether the cardioprotective effects of CAL are related to its antipyroptotic effect. A cardiatoxicity model was established by stimulating H9c2 cells and C57BL/6J mice using DOX. In vitro, CAL increased H9c2 cell viability and decreased DOX-induced pyroptosis via NLRP3, caspase-1, and gasdermin D signaling pathways in a dose-dependent manner. In vivo, CAL-DOX cotreatment effectively suppressed DOX-induced cytotoxicity as well as inflammatory and cardiomyocyte pyroptosis via the same molecular mechanism. Next, we used nigericin (Nig) and NLRP3 forced overexpression to determine whether CAL imparts antipyroptotic effects by inhibiting the NLRP3 inflammasome in vitro. Furthermore, CAL suppressed DOX-induced mitochondrial oxidative stress injury in H9c2 cells by decreasing the generation of reactive oxygen species and increasing mitochondrial membrane potential and adenosine triphosphate. Likewise, CAL attenuated the DOX-induced increase in malondialdehyde content and decreased superoxide dismutase and glutathione peroxidase activities in H9c2 cells. In vivo, CAL afforded a protective effect against DOX-induced cardiac injury by improving myocardial function, inhibiting brain natriuretic peptide, and improving the changes of the histological morphology of DOX-treated mice. Collectively, our findings confirmed that CAL alleviates DOX-induced cardiotoxicity and pyroptosis by inhibiting NLRP3 inflammasome activation in vivo and in vitro.

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A High Content Screen for Mucin-1-Reducing Compounds Identifies Fostamatinib as a Candidate for Rapid Repurposing for Acute Lung Injury during the COVID-19 pandemic

10.1101/2020.06.30.180380 ◽

2020 ◽

Cited By ~ 1

Author(s):

Maria Alimova ◽

Eriene-Heidi Sidhom ◽

Abhigyan Satyam ◽

Moran Dvela-Levitt ◽

Michelle Melanson ◽

...

Keyword(s):

Acute Lung Injury ◽

Epithelial Cells ◽

Lung Injury ◽

Drug Repurposing ◽

Lung Epithelial Cells ◽

Drug Candidate ◽

Mucin 1 ◽

Standing Up

SummaryDrug repurposing is the only method capable of delivering treatments on the shortened time-scale required for patients afflicted with lung disease arising from SARS-CoV-2 infection. Mucin-1 (MUC1), a membrane-bound molecule expressed on the apical surfaces of most mucosal epithelial cells, is a biochemical marker whose elevated levels predict the development of acute lung injury (ALI) and respiratory distress syndrome (ARDS), and correlate with poor clinical outcomes. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce MUC1 protein abundance. Our screen identified Fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo, Fostamatinib reduced MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro, SYK inhibition by Fostamatinib promoted MUC1 removal from the cell surface. Our work reveals Fostamatinib as a repurposing drug candidate for ALI and provides the rationale for rapidly standing up clinical trials to test Fostamatinib efficacy in patients with COVID-19 lung injury.

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Use of a Mechanism-based Toxicological Approach to Analyze the Pulmonary Pro-Fibrogenic Effects of Air Pollution PM2.5 Particulates

10.21203/rs.2.22194/v1 ◽

2020 ◽

Author(s):

Wei Cao ◽

Xiang Wang ◽

Ming Yan ◽

Chong Hyun Chang ◽

Joshua Kim ◽

...

Keyword(s):

Nlrp3 Inflammasome ◽

Fine Particulate Matter ◽

Lung Epithelial Cells ◽

Chronic Obstructive ◽

Inflammasome Activation ◽

Nlrp3 Inflammasome Activation ◽

Oropharyngeal Aspiration ◽

Tgf Β1

Abstract Background Airborne fine particulate matter (PM2.5) has been known capable of causing acute and chronic respiratory inflammation such as chronic obstructive pulmonary disease (COPD) and lung fibrosis. With incremental experience in the predictive toxicological approach on the potential adverse effects of nanomaterials, it is logical to explore the feasibility of using such a mechanism-based approach on PM2.5-induced lung toxicity. Results In this study, we collected a panel of eight PM2.5 samples for a comparative analysis of their pro-fibrogenic effects in the lung. These samples were collected on filters in November 2017 in Zhengzhou, Henan, China. In vitro screening shows although the PM2.5 particles did not induce significant cytotoxicity, they cause potent TNF-α and interleukin-1β (IL-1β) production in THP-1 cells as well as TGF-β1 in BEAS-2B lung epithelial cells. PM2.5 induced IL-1β production was shown to involve NLRP3 inflammasome activation, which was evidenced by the inhibited IL-1β production in NLRP3- and ASC-deficient cells and use of an inhibitor for cathepsin B, a known activation of the inflammasome through lysosomal damage pathway. Administration of PM2.5 to the lung in mice via oropharyngeal aspiration confirmed that the particles could induce TGF-β1 production in the bronchoalveolar lavage (BAL) fluid and collagen deposition in the lung at 21 days post-exposure, suggesting PM2.5 has the potential to induce pulmonary fibrosis. The ranking of the pro-fibrogenic effects by the PM2.5 samples in vivo was consistent with that of the IL-1β production in vitro. Conclusions In summary, we demonstrate that the PM2.5 is capable of inducing NLRP3 inflammasome activation and a series of cellular responses originating from the epithelial–mesenchymal trophic cell unit in the lung to induce fibrosis in vivo.

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Suppression of lncRNA NLRP3 inhibits NLRP3-triggered inflammatory responses in early acute lung injury

Cell Death and Disease ◽

10.1038/s41419-021-04180-y ◽

2021 ◽

Vol 12 (10) ◽

Author(s):

Deqiang Luo ◽

Wei Dai ◽

Xiaojin Feng ◽

Chengzhi Ding ◽

Qiang Shao ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Inflammatory Response ◽

Nlrp3 Inflammasome ◽

Receptor Protein ◽

Luciferase Reporter ◽

Lung Pathology ◽

Caspase 1

AbstractAcute lung injury (ALI) is a common lung pathology that is accompanied by alveolar macrophage (AM) activation and inflammatory response. This study investigated the role of the long non-coding RNA NONRATT004344 (hereafter named lncRNA NLRP3) in regulating the Nod-like receptor protein 3 (NLRP3)-triggered inflammatory response in early ALI and the underlying mechanism as well. We established LPS-induced ALI models to explore their interactive mechanisms in vitro and in vivo. Luciferase reporter assays were performed to determine that miR-138-5p could bind to lncRNA NLRP3 and NLRP3. We observed increased lncRNA NLRP3 expression, decreased miR-138-5p expression, NLRP3 inflammasome activation, and upregulated caspase-1, IL-1β, and IL-18 expression in the LPS-induced ALI model. Furthermore, lncRNA NLRP3 overexpression activated the NLRP3 inflammasome and promoted IL-1β and IL-18 secretion; the miR-138-5p mimic abolished these effects in vivo and in vitro. Consistently, miR-138-5p inhibition reversed the effects of lncRNA NLRP3 silencing on the expression of NLRP3-related molecules and inhibition of the NLRP3/caspase-1/IL-1β signalling pathway. Mechanistically, lncRNA NLRP3 sponging miR-138-5p facilitated NLRP3 activation through a competitive endogenous RNA (ceRNA) mechanism. In summary, our results suggested that lncRNA NLRP3 binding miR-138-5p promotes NLRP3-triggered inflammatory response via lncRNA NLRP3/miR-138-5p/NLRP3 ceRNA network (ceRNET) and provides insights into the treatment of early ALI.

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Honokiol alleviates LPS-induced acute lung injury by inhibiting NLRP3 inflammasome-mediated pyroptosis via Nrf2 activation in vitro and in vivo

10.21203/rs.3.rs-917410/v1 ◽

2021 ◽

Author(s):

yuhan liu ◽

jiabin zhou ◽

yingying luo ◽

jinxiao li ◽

luorui shang ◽

...

Keyword(s):

Oxidative Stress ◽

Acute Lung Injury ◽

Lung Injury ◽

Nlrp3 Inflammasome ◽

Epithelial Cell Line ◽

Protective Mechanism ◽

Expression Levels ◽

Nrf2 Activation

Abstract Background Honokiol (HKL) has been reported to ameliorate lipopolysaccharide (LPS)-induced acute lung injury (ALI). However, its potential mechanism imparting the protective effects remains unclear. In this study, the protective mechanism of HKL on LPS-induced ALI was explored in vivo and in vitro. Methods In vivo, the SD rats were intratracheally instilled with LPS (5 mg/kg) to establish an acute lung injury model and then treated with HKL (1.25/2.5/5 mg/kg) or ML385 (30 mg/kg) intraperitoneally. In vitro, the human bronchial epithelial cell line (BEAS-2B) was stimulated with LPS and ATP to induce pyroptosis and treated with HKL (12.5/25/50 µM). Small interfering RNA (siRNA) technique was used to knockdown Nrf2 in BEAS-2B cells. The protein and mRNA expression levels of Nrf2, HO-1, NLRP3, ASC, CASP1, and GSDMD in cells and lung tissues were detected by western blot and real time-PCR. The expression levels of interleukin (IL)-1β, IL-18, MPO, MDA, and SOD in bronchoalveolar lavage fluid (BALF) and supernatant were determined by ELISA. The degree of pathological injury of lung tissue was evaluated by H&E staining. Results The results showed that HKL could alleviate the oxidative stress and inflammatory responses by regulating the levels of MPO, MDA, SOD, IL-1β, IL-18 in supernatant. And HKL inhibited the expression levels of NLRP3, ASC, CASP1, GSDMD via activation of Nrf2 in BEAS-2B cells. Further studies revealed that HKL could attenuate the pathological injury in LPS-induced ALI rats and the molecular mechanism was consistent with the results in vitro. Conclusions Our study demonstrated that HKL could alleviate LPS-induced ALI by reducing the oxidative stress and inhibiting NLRP3 inflammasome-mediated pyroptosis, which was partly dependent on the Nrf2 activation.

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