Carbon monoxide provides protection  against hyperoxic lung injury

Findings in recent years strongly suggest that the stress-inducible gene heme oxygenase (HO)-1 plays an important role in protection against oxidative stress. Although the mechanism(s) by which this protection occurs is poorly understood, we hypothesized that the gaseous molecule carbon monoxide (CO), a major by-product of heme catalysis by HO-1, may provide protection against oxidative stress. We demonstrate here that animals exposed to a low concentration of CO exhibit a marked tolerance to lethal concentrations of hyperoxia in vivo. This increased survival was associated with highly significant attenuation of hyperoxia-induced lung injury as assessed by the volume of pleural effusion, protein accumulation in the airways, and histological analysis. The lungs were completely devoid of lung airway and parenchymal inflammation, fibrin deposition, and pulmonary edema in rats exposed to hyperoxia in the presence of a low concentration of CO. Furthermore, exogenous CO completely protected against hyperoxia-induced lung injury in rats in which endogenous HO enzyme activity was inhibited with tin protoporphyrin, a selective inhibitor of HO. Rats exposed to CO also exhibited a marked attenuation of hyperoxia-induced neutrophil infiltration into the airways and total lung apoptotic index. Taken together, our data demonstrate, for the first time, that CO can be therapeutic against oxidative stress such as hyperoxia and highlight possible mechanism(s) by which CO may mediate these protective effects.

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PECAM-directed delivery of catalase to endothelium protects against pulmonary vascular oxidative stress

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00021.2003 ◽

2003 ◽

Vol 285 (2) ◽

pp. L283-L292 ◽

Cited By ~ 61

Author(s):

Melpo Christofidou-Solomidou ◽

Arnaud Scherpereel ◽

Rainer Wiewrodt ◽

Kimmie Ng ◽

Thomas Sweitzer ◽

...

Keyword(s):

Oxidative Stress ◽

Lung Injury ◽

Intravenous Injection ◽

Targeted Delivery ◽

Ischemia Reperfusion ◽

Therapeutic Interventions ◽

Protective Effects ◽

Stress Injury ◽

Pulmonary Endothelium

Targeted delivery of drugs to vascular endothelium promises more effective and specific therapies in many disease conditions, including acute lung injury (ALI). This study evaluates the therapeutic effect of drug targeting to PECAM (platelet/endothelial cell adhesion molecule-1) in vivo in the context of pulmonary oxidative stress. Endothelial injury by reactive oxygen species (e.g., H2O2) is involved in many disease conditions, including ALI/acute respiratory distress syndrome and ischemia-reperfusion. To optimize delivery of antioxidant therapeutics, we conjugated catalase with PECAM antibodies and tested properties of anti-PECAM/catalase conjugates in cell culture and mice. Anti-PECAM/catalase, but not an IgG/catalase counterpart, bound specifically to PECAM-expressing cells, augmented their H2O2-degrading capacity, and protected them against H2O2 toxicity. Anti-PECAM/catalase, but not IgG/catalase, rapidly accumulated in the lungs after intravenous injection in mice, where it was confined to the pulmonary endothelium. To test its protective effect, we employed a murine model of oxidative lung injury induced by glucose oxidase coupled with thrombomodulin antibody (anti-TM/GOX). After intravenous injection in mice, anti-TM/GOX binds to pulmonary endothelium and produces H2O2, which causes lung injury and 100% lethality within 7 h. Coinjection of anti-PECAM/catalase protected against anti-TM/GOX-induced pulmonary oxidative stress, injury, and lethality, whereas polyethylene glycol catalase or IgG/catalase conjugates afforded only marginal protective effects. This result validates vascular immunotargeting as a prospective strategy for therapeutic interventions aimed at immediate protective effects, e.g., for augmentation of antioxidant defense in the pulmonary endothelium and treatment of ALI.

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Tanreqing Inhibits LPS-Induced Acute Lung Injury In Vivo and In Vitro Through Downregulating STING Signaling Pathway

Frontiers in Pharmacology ◽

10.3389/fphar.2021.746964 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yu-Qiong He ◽

Can-Can Zhou ◽

Jiu-Ling Deng ◽

Liang Wang ◽

Wan-Sheng Chen

Keyword(s):

Oxidative Stress ◽

Acute Lung Injury ◽

Lung Injury ◽

Signaling Pathway ◽

Inflammatory Responses ◽

Lung Edema ◽

Protective Effects ◽

And Oxidative Stress

Acute lung injury (ALI) is a common life-threatening lung disease, which is mostly associated with severe inflammatory responses and oxidative stress. Tanreqing injection (TRQ), a Chinese patent medicine, is clinically used for respiratory-related diseases. However, the effects and action mechanism of TRQ on ALI are still unclear. Recently, STING as a cytoplasmic DNA sensor has been found to be related to the progress of ALI. Here, we showed that TRQ significantly inhibited LPS-induced lung histological change, lung edema, and inflammatory cell infiltration. Moreover, TRQ markedly reduced inflammatory mediators release (TNF-α, IL-6, IL-1β, and IFN-β). Furthermore, TRQ also alleviated oxidative stress, manifested by increased SOD and GSH activities and decreased 4-HNE, MDA, LDH, and ROS activities. In addition, we further found that TRQ significantly prevented cGAS, STING, P-TBK, P-P65, P-IRF3, and P-IκBα expression in ALI mice. And we also confirmed that TRQ could inhibit mtDNA release and suppress signaling pathway mediated by STING in vitro. Importantly, the addition of STING agonist DMXAA dramatically abolished the protective effects of TRQ. Taken together, this study indicated that TRQ alleviated LPS-induced ALI and inhibited inflammatory responses and oxidative stress through STING signaling pathway.

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Inhaled carbon monoxide and hyperoxic lung injury in rats

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.2001.281.4.l949 ◽

2001 ◽

Vol 281 (4) ◽

pp. L949-L957 ◽

Cited By ~ 35

Author(s):

Carolyn E. Clayton ◽

Martha Sue Carraway ◽

Hagir B. Suliman ◽

Edward D. Thalmann ◽

Katherine N. Thalmann ◽

...

Keyword(s):

Carbon Monoxide ◽

Lung Injury ◽

Pleural Fluid ◽

Manganese Superoxide Dismutase ◽

Apoptotic Cell ◽

Weight Ratio ◽

Dry Weight ◽

Heme Oxygenase 1 ◽

Protective Effects ◽

Hyperoxic Lung Injury

Because carbon monoxide (CO) has been proposed to have anti-inflammatory properties, we sought protective effects of CO in pulmonary O2 toxicity, which leads rapidly to lung inflammation and respiratory failure. Based on published studies, we hypothesized that CO protects the lung against O2 by selectively increasing expression of antioxidant enzymes, thereby decreasing oxidative injury and inflammation. Rats exposed to O2 with or without CO [50–500 parts/million (ppm)] for 60 h were compared for lung wet-to-dry weight ratio (W/D), pleural fluid volume, myeloperoxidase (MPO) activity, histology, expression of heme oxygenase-1 (HO-1), and manganese superoxide dismutase (Mn SOD) proteins. The brains were evaluated for histological evidence of damage from CO. In O2-exposed animals, lung W/D increased from 4.8 in normal rats to 6.3; however, only CO at 200 and 500 ppm decreased W/D significantly (to 5.9) during O2 exposure. Large volumes of pleural fluid accumulated in all rats, with no significant CO treatment effect. Lung MPO values increased after O2 and were not attenuated by CO treatment. CO did not enhance lung expression of oxidant-responsive proteins Mn SOD and HO-1. Animals receiving O2 and CO at 200 or 500 ppm showed significant apoptotic cell death in the cortex and hippocampus by immunochemical staining. Thus significant protection by CO against O2-induced lung injury could not be confirmed in rats, even at CO concentrations associated with apoptosis in the brain.

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Protective Effect of Xiao-Xu-Ming Decoction-Mediated Inhibition of ROS/NLRP3 Axis on Lipopolysaccharide-Induced Acute Lung Injury In Vitro and In Vivo

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/8257495 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Yijin Xiang ◽

Min Cai ◽

Xiangting Li ◽

Xuxia Bao ◽

Dingfang Cai

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Neutrophil Infiltration ◽

Alveolar Epithelial Cells ◽

Cell Permeability ◽

Protective Effects ◽

Barrier Dysfunction ◽

Caspase 1

Background. As a traditional Chinese medicine prescription, Xiao-Xu-Ming decoction (XXMD) could reduce the incidence of lung infection of patients with cerebral infarction. Nonetheless, the therapeutic mechanisms of XXMD in acute lung injury (ALI) remain to be elucidated. Our study was aimed to assess the effects of XXMD protects against ALI. Methods. ALI model was induced by intraperitoneal injection of lipopolysaccharide (LPS) in vivo. In vitro, human pulmonary alveolar epithelial cells (HPAEpiC) were treated with XXMD and were followed by LPS treatment. The levels of ZO-1, CLDN4, NLRP3, and caspase 1 were detected by Western blot, and the content of IL-1 and IL-18 was determined by ELISA. Transepithelial electrical resistance was used to detect the cell permeability. The reactive oxygen species (ROS) levels within the cells were evaluated by flow cytometry. Results. Our results showed that XXMD attenuated LPS-induced oxidative stress, barrier dysfunction, and the activation of NLRP3 inflammasome in vitro, as evidenced by enhanced ROS production, TEER levels, expression of NLRP3 and caspase 1 (p20) and release of IL-1β and IL-18, and weakened cell permeability. In addition, XXMD could counteract the effects of NLRP3 overexpression on HPAEpiC and vice versa. XXMD treatment also ameliorated the degree of neutrophil infiltration, barrier dysfunction, and the activation of NLRP3 in LPS-induced ALI lung tissues in vivo. Conclusion. The findings showed that XXMD could alleviate LPS-induced ALI injury and inhibit inflammation and suppress ROS/NLRP3 signaling pathway, which were involved in these protective effects.

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Protectin conjugates in tissue regeneration 1 restores lipopolysaccharide-induced pulmonary endothelial glycocalyx loss via ALX/SIRT1/NF-kappa B axis

Respiratory Research ◽

10.1186/s12931-021-01793-x ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Xin-Yang Wang ◽

Xin-Yu Li ◽

Cheng-Hua Wu ◽

Yu Hao ◽

Pan-Han Fu ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Inflammatory Cytokines ◽

Tissue Regeneration ◽

Umbilical Vein ◽

Endothelial Glycocalyx ◽

Lipid Mediator ◽

Protective Effects ◽

Pulmonary Vascular Permeability

Abstract Background Endothelial glycocalyx loss is integral to increased pulmonary vascular permeability in sepsis-related acute lung injury. Protectin conjugates in tissue regeneration 1 (PCTR1) is a novel macrophage-derived lipid mediator exhibiting potential anti-inflammatory and pro-resolving benefits. Methods PCTR1 was administrated intraperitoneally with 100 ng/mouse after lipopolysaccharide (LPS) challenged. Survival rate and lung function were used to evaluate the protective effects of PCTR1. Lung inflammation response was observed by morphology and inflammatory cytokines level. Endothelial glycocalyx and its related key enzymes were measured by immunofluorescence, ELISA, and Western blot. Afterward, related-pathways inhibitors were used to identify the mechanism of endothelial glycocalyx response to PCTR1 in mice and human umbilical vein endothelial cells (HUVECs) after LPS administration. Results In vivo, we show that PCTR1 protects mice against lipopolysaccharide (LPS)-induced sepsis, as shown by enhanced the survival and pulmonary function, decreased the inflammatory response in lungs and peripheral levels of inflammatory cytokines such as tumor necrosis factor-α, interleukin-6, and interleukin-1β. Moreover, PCTR1 restored lung vascular glycocalyx and reduced serum heparin sulphate (HS), syndecan-1 (SDC-1), and hyaluronic acid (HA) levels. Furthermore, we found that PCTR1 downregulated heparanase (HPA) expression to inhibit glycocalyx degradation and upregulated exostosin-1 (EXT-1) protein expression to promote glycocalyx reconstitution. Besides, we observed that BAY11-7082 blocked glycocalyx loss induced by LPS in vivo and in vitro, and BOC-2 (ALX antagonist) or EX527 (SIRT1 inhibitor) abolished the restoration of HS in response to PCTR1. Conclusion PCTR1 protects endothelial glycocalyx via ALX receptor by regulating SIRT1/NF-κB pathway, suggesting PCTR1 may be a significant therapeutic target for sepsis-related acute lung injury.

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Protective Effects of Taraxacum officinale L. (Dandelion) Root Extract in Experimental Acute on Chronic Liver Failure

Antioxidants ◽

10.3390/antiox10040504 ◽

2021 ◽

Vol 10 (4) ◽

pp. 504

Author(s):

Iulia Olimpia Pfingstgraf ◽

Marian Taulescu ◽

Raluca Maria Pop ◽

Remus Orăsan ◽

Laurian Vlase ◽

...

Keyword(s):

Oxidative Stress ◽

Liver Failure ◽

Tissue Injury ◽

Taraxacum Officinale ◽

Chronic Liver ◽

Root Extract ◽

Protective Effects ◽

Stress Tests ◽

Chronic Liver Failure

Background: Taraxacum officinale (TO) or dandelion has been frequently used to prevent or treat different liver diseases because of its rich composition in phytochemicals with demonstrated effect against hepatic injuries. This study aimed to investigate the possible preventing effect of ethanolic TO root extract (TOERE) on a rat experimental acute on chronic liver failure (ACLF) model. Methods: Chronic liver failure (CLF) was induced by human serum albumin, and ACLF was induced in CLF by D-galactosamine and lipopolysaccharide (D-Gal-LPS). Five groups (n = 5) of male Wistar rats (200–250 g) were used: ACLF, ACLF-silymarin (200 mg/kg b.w./day), three ACLF-TO administered in three doses (200 mg, 100 mg, 50 mg/kg b.w./day). Results: The in vivo results showed that treatment with TOERE administered in three chosen doses before ACLF induction reduced serum liver injury markers (AST, ALT, ALP, GGT, total bilirubin), renal tests (creatinine, urea), and oxidative stress tests (TOS, OSI, MDA, NO, 3NT). Histopathologically, TOERE diminished the level of liver tissue injury and 3NT immunoexpression. Conclusions: This paper indicated oxidative stress reduction as possible mechanisms for the hepatoprotective effect of TOERE in ACLF and provided evidence for the preventive treatment.

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Ezetimibe Attenuates Oxidative Stress and Neuroinflammation via the AMPK/Nrf2/TXNIP Pathway after MCAO in Rats

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/4717258 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14 ◽

Cited By ~ 2

Author(s):

Jing Yu ◽

Wen-na Wang ◽

Nathanael Matei ◽

Xue Li ◽

Jin-wei Pang ◽

...

Keyword(s):

Oxidative Stress ◽

Ischemic Stroke ◽

Brain Infarction ◽

Neutrophil Infiltration ◽

Artery Occlusion ◽

Receptor Protein ◽

Related Factor ◽

Protective Effects ◽

Sprague Dawley ◽

Interacting Protein

Oxidative stress and neuroinflammation play essential roles in ischemic stroke-induced brain injury. Previous studies have reported that Ezetimibe (Eze) exerts antioxidative stress and anti-inflammatory properties in hepatocytes. In the present study, we investigated the effects of Eze on oxidative stress and neuroinflammation in a rat middle cerebral artery occlusion (MCAO) model. One hundred and ninety-eight male Sprague-Dawley rats were used. Animals assigned to MCAO were given either Eze or its control. To explore the downstream signaling of Eze, the following interventions were given: AMPK inhibitor dorsomorphin and nuclear factor erythroid 2-related factor 2 (Nrf2) siRNA. Intranasal administration of Eze, 1 h post-MCAO, further increased the endogenous p-AMPK expression, reducing brain infarction, neurologic deficits, neutrophil infiltration, microglia/macrophage activation, number of dihydroethidium- (DHE-) positive cells, and malonaldehyde (MDA) levels. Specifically, treatment with Eze increased the expression of p-AMPK, Nrf2, and HO-1; Romo-1, thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), Cleaved Caspase-1, and IL-1β were reduced. Dorsomorphin and Nrf2 siRNA reversed the protective effects of Eze. In summary, Eze decreases oxidative stress and subsequent neuroinflammation via activation of the AMPK/Nrf2/TXNIP pathway after MCAO in rats. Therefore, Eze may be a potential therapeutic approach for ischemic stroke patients.

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Lidocaine Alleviates Sepsis-Induced Acute Lung Injury in Mice by Suppressing Tissue Factor and Matrix Metalloproteinase-2/9

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/3827501 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Binbin Zheng ◽

Hongbo Yang ◽

Jianan Zhang ◽

Xueli Wang ◽

Hao Sun ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Matrix Metalloproteinase ◽

Gelatin Zymography ◽

Neutrophil Infiltration ◽

Negative Regulator ◽

Matrix Metalloproteinase 2 ◽

Cytokine Signaling

Acute lung injury (ALI) is one of the fatal symptoms of sepsis. However, there were no effective clinical treatments. TF accumulation-induced fibrin deposit formations and coagulation abnormalities in pulmonary vessels contribute to the lethality of ALI. Suppressor of cytokine signaling 3 (SOCS3) acts as an endogenous negative regulator of the TLR4/TF pathway. We hypothesized that inducing SOCS3 expression using lidocaine to suppress the TLR4/TF pathway may alleviate ALI. Hematoxylin and eosin (H&E), B-mode ultrasound, and flow cytometry were used to measure the pathological damage of mice. Gelatin zymography was used to measure matrix metalloproteinase-2/9 (MMP-2/9) activities. Western blot was used to assay the expression of protein levels. Here, we show that lidocaine could increase the survival rate of ALI mice and ameliorate the lung injury of ALI mice including reducing the edema, neutrophil infiltration, and pulmonary thrombosis formation and increasing blood flow velocity. Moreover, in vitro and in vivo, lidocaine could increase the expression of p-AMPK and SOCS3 and subsequently decrease the expression of p-ASK1, p-p38, TF, and the activity of MMP-2/9. Taken together, our study demonstrated that lidocaine could inhibit the TLR4/ASK1/TF pathway to alleviate ALI via activating AMPK-SOCS3 axis.

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Huangkui Capsule Attenuates Lipopolysaccharide-Induced Acute Lung Injury and Macrophage Activation by Suppressing Inflammation and Oxidative Stress in Mice

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/6626483 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Jinfang Deng ◽

Zhenpeng He ◽

Xiuru Li ◽

Wei Chen ◽

Ziwen Yu ◽

...

Keyword(s):

Oxidative Stress ◽

Acute Lung Injury ◽

Lung Injury ◽

Macrophage Activation ◽

Neutrophil Infiltration ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Myeloperoxidase Activity ◽

Tnf Α ◽

And Oxidative Stress

Background. Huangkui capsule (HKC) comprises the total flavonoid extract of flowers of Abelmoschus manihot (L.) Medicus. This study aimed to explore the effects of HKC on lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice and LPS-stimulated RAW 264.7 cells. Methods. Enzyme-linked immunosorbent assay, histopathology, spectrophotometry, and quantitative real-time polymerase chain reaction were used for the assessments. Statistical analysis was performed using a one-way analysis of variance. Results. LPS significantly increased lung inflammation, neutrophil infiltration, and oxidative stress and downregulated lung miR-451 expression. Treatment with HKC dramatically attenuated the lung wet/dry weight ratio, reduced the total cell count in the bronchoalveolar lavage fluid (BALF), and inhibited myeloperoxidase activity in the lung tissues 24 h after LPS challenge. Histopathological analysis demonstrated that HKC attenuated LPS-induced tissue oedema and neutrophil infiltration in the lung tissues. Additionally, the concentrations of tumour necrosis factor- (TNF-) α and interleukin- (IL-) 6 in BALF and IL-6 in the plasma reduced after HKC administration. Moreover, HKC could enhance glutathione peroxidase and catalase activities and upregulate the expression of miR-451 in the lung tissues. In vitro experiments revealed that HKC inhibited the production of nitric oxide, TNF-α, and IL-6 in LPS-induced RAW 264.7 cells and mouse primary peritoneal macrophages. Additionally, HKC downregulated LPS-induced transcription of TNF-α and IL-6 in RAW 264.7 cells. Conclusions. These findings suggest that HKC has anti-inflammatory and antioxidative effects that may protect mice against LPS-induced ALI and macrophage activation.

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