scholarly journals Saquinavir Ameliorates Liver Warm Ischemia-Reperfusion-Induced Lung Injury via HMGB-1- and P38/JNK-Mediated TLR-4-Dependent Signaling Pathways

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Zhuang Yu ◽  
Yao Tong ◽  
Renlingzi Zhang ◽  
Xibing Ding ◽  
Quan Li

Liver ischemia and reperfusion (I/R) induce local and distant tissue injuries, contributing to morbidity and mortality in a wider range of pathologies. This is especially seen under uncontrolled aseptic inflammatory conditions, leading to injury of remote organs, such as lung injury, and even failure. Saquinavir (SQV) is a kind of HIV protease inhibitor that possesses an anti-inflammatory property. In this study, we investigated whether SQV suppresses Toll-like receptor 4- (TLR4-) dependent signaling pathways of high-mobility group box 1 (HMGB1) and P38/JNK, conferring protection against murine liver I/R-induced lung injury. To investigate our hypothesis, C57BL/6 mice and TLR4 knockout mice (TLR4−/−) were used to perform the study. SQV administration markedly attenuated remote lung tissue injury after 1-hour ischemia and 6-hour reperfusion of the liver. To our expectation, SQV attenuated I/R-induced lung edema, hyperpermeability, and pathological injury. The beneficial effects of SQV were associated with decreased levels of circulating and lung tissue inflammatory cytokines, such as IL-6, IL-1β, TNF-α, and iNOS. The protective effect of SQV was also associated with decreased lung tissue expression of HMGB1, TLR-4, and p-P38/JNK, but not p-ERK in wild-type liver I/R mice. Overall, this study demonstrated a new role of SQV, facilitating negative regulation of HMGB1- and P38/JNK-mediated TLR-4-dependent signaling pathways, conferring protection against liver I/R-induced lung injury.

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Haifa Xia ◽  
Jingxu Wang ◽  
Shujun Sun ◽  
Fuquan Wang ◽  
Yiyi Yang ◽  
...  

As one of the basic treatment modalities in the intensive care unit (ICU), mechanical ventilation can cause or aggravate acute lung injury or ventilator-induced lung injury (VILI). Resolvin D1 (RvD1) is an endogenous polyunsaturated fatty acid derivative with strong anti-inflammatory action. In this study, we explored if RvD1 possesses a protective effect on VILI. Mice were ventilated with high tidal volume (40 mL/kg, HVT) for 4 h and were then intraperitoneally administered RvD1 at the beginning of high tidal volume ventilation and given GW9662 (a PPAR-γ antagonist) intraperitoneally 30 min before ventilation. RvD1 attenuated VILI, as evidenced by improved oxygenation and reduced histological injury, compared with HVT -induced lung injury. Similarly, it could ameliorate neutrophil accumulation and production of proinflammatory cytokines in lung tissue. In contrast, the protective effect of RvD1 on lung tissue could be reversed by GW9662. RvD1 mitigated VILI by activating peroxisome proliferator-activated receptor gamma (PPAR-γ) and inhibiting nuclear factor-kappa B (NF-κB) signaling pathways in mice. In conclusion, RvD1 could reduce the inflammatory response in VILI by activating PPAR-γ and inhibiting NF-κB signaling pathways.


2021 ◽  
Author(s):  
Can Jin ◽  
Shucheng Zhang ◽  
Linlin Wu ◽  
Bohan Li ◽  
Meimei Shi ◽  
...  

Abstract Rationale: It is unclear whether removing the danger-associated molecular patterns (DAMPs) of gut lymph (GL) in the rats of gut ischemia-reperfusion injury (GIRI) model may reduce the distant organ lung injury.Objective: To determine whether oXiris gut lymph purification (GLP) may remove the DAMPs of GL in the rats’ model of acute lung injury (ALI) caused by GIRI.Methods: The experimental rats were divided into four groups: Sham group, GIRI group, GIRI + gut lymph drainage (GLD) group, and GIRI + GLP group. After successful modeling, the lung tissue samples of rats in each group were taken for hematoxylin-eosin (HE) staining and detection of expression levels of apoptotic indexes. The level of DAMPs was detected in blood and lymph. We observed its microstructure of type II alveolar epithelial cells (AECⅡ), and detected the expression level of apoptosis indexes.Measurements and Main Results: GIRI-induced destruction of alveolar structure, thickened alveolar walls, inflammatory cell infiltration emerged in the GIRI group, HMGB-1 and IL-6 levels significantly increased, and HSP70 and IL-10 levels reduced in lymph and serum. Compared with GIRI group, the lung tissue damage in GIRI + GLP group significantly improved, the expression level of HMGB-1 and IL-6 in the lymph and serum reduced, and HSP70 and IL-10 increased. The organelle structure of AECII in GIRI + GLP group was significantly improved compared with the GIRI group. Conclusions: oXiris GLP blocks the key link between DAMPs and mononuclear phagocyte system to inhibit inflammation and cell apoptosis, thereby reducing ALI induced by GIRI.


2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Quanchao Sun ◽  
You Wu ◽  
Feng Zhao ◽  
Jianjun Wang

Lung ischemia/reperfusion (I/R) injury occurs in various clinical conditions and heavily damaged lung function. Oxidative stress reaction and antioxidant enzymes play a pivotal role in the etiopathogenesis of lung I/R injury. In the current study, we investigated the impact of Maresin 1 on lung I/R injury and explored the possible mechanism involved in this process. MaR 1 ameliorated I/R-induced lung injury score, wet/dry weight ratio, myeloperoxidase, tumor necrosis factor, bronchoalveolar lavage fluid (BALF) leukocyte count, BALF neutrophil ratio, and pulmonary permeability index levels in lung tissue. MaR 1 significantly reduced ROS, methane dicarboxylic aldehyde, and 15-F2t-isoprostane generation and restored antioxidative enzyme (superoxide dismutase, glutathione peroxidase, and catalase) activities. Administration of MaR 1 improved the expression of nuclear Nrf-2 and cytosolic HO-1 in I/R-treated lung tissue. Furthermore, we also found that the protective effects of MaR 1 on lung tissue injury and oxidative stress were reversed by HO-1 activity inhibitor, Znpp-IX. Nrf-2 transcription factor inhibitor, brusatol, significantly decreased MaR 1-induced nuclear Nrf-2 and cytosolic HO-1 expression. In conclusion, these results indicate that MaR 1 protects against lung I/R injury through suppressing oxidative stress. The mechanism is partially explained by activation of the Nrf-2-mediated HO-1 signaling pathway.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3827-3827
Author(s):  
Takashi Ito ◽  
Kazuhiro Abeyama ◽  
Ko-ichi Kawahara ◽  
Kamal K. Biswas ◽  
Tomonori Uchimura ◽  
...  

Abstract High Mobility Group box 1(HMGB1) is an abundant DNA-binding protein that acts as a proinflammatory cytokine when released in the extracellular milieu by necrotic and inflammatory cells. Moreover, an increased HMGB1 in the circulation of septic patients may induce multi-organ failure and lethality. However, very recent observations suggest that the protein also acts as an innate adjuvant, stem cell chemoattractant and growth factor. Thus only systemic and circulatory HMGB1 may induce morbidity and mortality, however, localized HMGB1 may have beneficial effects. Therefore, we serially examined the serum HMGB1 level in patients with various diseases, and also evaluated the significance of the protein. We demonstrate here how HMGB1 is localized and acts as an immune-adjuvant and a repairing factor in damaged tissue. We first established specific ELISA method to measure HMGB1. An increased level of HMGB1 was detected in the serum from patients with sever sepsis, infections, malignancy and so on. However, serum HMGB1 concentrations were fluctuated during the clinical course, and could not be concluded as a lethal mediator as previously reported. Next we investigated the reason of dynamic fluctuations of the protein in the circulation. Based on our findings, we proposed that this fluctuation of HMGB1 concentrations may be mediated by at least following three fashions; 1) proteolytic degradation by plasmin and thrombin, 2) endothelial thrombomodulin(TM) adsorption, and 3) generation of antibody against the protein. We observed that plasmin efficiently degraded HMGB1 into small fragments. However, interestingly the generated fragments of the protein still possess an ability to produce TNFa in macrophages through an undefined pathway. TM binds the protein on its N-terminus lectin-like domain. Binding of HMGB1 to TM resulted in decrement of TM’s cofactor activity to activate protein C by thrombin. HMGB1 bound to TM was gradually degraded by thrombin. These may be a system to localize HMGB1 only in injury sites where TM is down-regulated or disappeared through endothelial-loss. This may exert endothelial defense system against extracellular HMGB1 in severe tissue injury. Another possibility is that the generated antibody against HMGB1 may neutralize the proinflammatory action of the protein. In this context, we found that some of the antibodies against HMGB1 have the characteristics of P-ANCA(perinuclear anti-neutrophil cytoplasmic antibody). This may alter the phenotype of the underlining diseases. In conclusion, we suggest that HMGB1 is not merely a lethal mediator, but a kind of “testament” mediator of cell necrosis or invasive attacks to dendritic cells.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Yan Zhu ◽  
Taocheng Meng ◽  
Aichen Sun ◽  
Jintao Li ◽  
Jinlai Li

Objective. This study aimed to explore the role of angelica polysaccharide (AP) in sepsis-induced acute lung injury (ALI) and its underlying molecular mechanism. Methods. A sepsis model of cecal ligation and puncture (CLP) in male BALB/C mice was used. Then, 24 h after CLP, histopathological changes in lung tissue, lung wet/dry weight ratio, and inflammatory cell infiltration were analyzed. Next, levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-18), as well as the activity of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH), were measured to assess the role of AP. The protein expression of NF-κB p65, p-NF-κB p65, IκBα, p-IκBα, nucleotide-binding domain- (NOD-) like receptor protein 3 (NLRP3), ASC, and caspase-1 was detected by western blot. In addition, the expression of p-NF-κB p65 and NLRP3 was detected by immunohistochemistry. Results. AP treatment ameliorated CLP-induced lung injury and lung edema, as well as decreased the number of total cells, neutrophils, and macrophages in bronchoalveolar lavage fluid (BALF). AP reduced the levels of TNF-α, IL-1β, IL-6, and IL-18 in BALF, as well as in serum. Moreover, AP decreased MPO activity and MDA content, whereas increased SOD and GSH levels. AP inhibited the expression of p-NF-κB p65, p-IκBα, NLRP3, ASC, and caspase-1, while promoted IκBα expression. Conclusion. This study demonstrated that AP exhibits protective effects against sepsis-induced ALI by inhibiting NLRP3 and NF-κB signaling pathways in mice.


2020 ◽  
Author(s):  
Lin Fei ◽  
Xiao Jingyuan ◽  
Liang Fangte ◽  
Dai Huijun ◽  
Ye Liu ◽  
...  

Abstract Background Lung ischemia-reperfusion injury (LIRI) is a common and complex pathophysiological process that can lead to poor patient outcomes. Inflammasome-dependent macrophage pyroptosis contributes to organ damage caused by ischemia-reperfusion (I/R). Oxidative stress reaction and antioxidant enzymes also play an important role in LIRI. This experiment was conducted to investigate whether preconditioning with rHMGB1 could ameliorate LIRI and explore the mechanisms of its protective effect in a lung I/R mice model. Methods Adult male mice were anesthetized and the left hilus pulmonis was clamped for 60 min, followed by 120 min of reperfusion. rHMGB1 was performed by intraperitoneal injection at 2 h before anesthesia. Brusatol (Nrf-2 antagonist) was given intraperitoneally every other day for a total of five times before surgery. Measurements of pathohistological lung tissue damage, pulmonary wet/dry (W/D) ratios, inflammatory mediators were performed to assess the extent of lung injury after I/R. Alveolar macrophages (AMs) pyroptosis were evaluated by LDH release, caspase-1 expression in flow cytometry, GSDMD expression in immunofluorescent staining. Measurement of the products of oxidative Stress (ROS, MDA, 15-F2t-Isoprostane) and the antioxidant enzymes (SOD, GSH-PX, CAT) were performed. Results Preconditioning with rHMGB1 significantly ameliorated I/R-induced lung injury through measuring the morphology, wet/dry weight ratio, the expressions of IL-1β, IL-6, NF-κB, HMGB1 in lung tissue. rHMGB1 preconditioning remarkably alleviated AMs pyroptosis induced by lung I/R. rHMGB1 preconditioning significantly reduced oxidative stress and restored the activity of antioxidative enzymes. In addition, rHMGB1 preconditioning mediated the activity of Keap1/Nrf-2/HO-1 pathway in LIRI. Furthermore, inhibiting Keap1/Nrf-2/HO-1 pathway through brusatol administration could aggravate lung tissue damage and inflammatory response after lung I/R. Also, brusatol administration could suppresse the antioxidant and anti-pyroptosis effects of rHMGB1 preconditioning in LIRI. Conclusions rHMGB1 preconditioning protects against LIRI through suppressing AMs pyroptosis. The mechanism is partially explained by inhibiting oxidative stress and improving the activity of antioxidative enzymes via Keap1/Nrf-2/HO-1 pathway.


Dose-Response ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 155932582096934
Author(s):  
Yijun Li ◽  
Shun Wang ◽  
Jinbo Liu ◽  
Xingyu Li ◽  
Meng Lu ◽  
...  

Pulmonary endothelial cell injury is a hallmark of acute lung injury. High-mobility group box 1 (HMGB1) can modulate the inflammatory response via endothelial cell activation and release of inflammatory molecules. Thus, we tested whether induced pluripotent stem cells (iPSCs) can alleviate ischemia/reperfusion (I/R) induced lung injury, and, if so, whether HMGB1 mediates the effect in a male C57BL/6 mouse model. Intravenously injected iPSCs into mice 2 h after I/R showed a significant attenuation of lung injury (assessed by lung mechanics, edema, and histology) 24 h after reperfusion (compared with controls), along with decreases in HMGB1, phosphorylated nuclear factor-κB, inflammatory cytokines [interleukin (IL)1β, IL6 and tumor necrosis factor-α], and the activation of endothelial cells. Furthermore, these effects of iPSCs can be mimicked by blocking HMGB1 with an inhibitor in vivo and in vitro. We conclude that iPSCs can be a potential therapy for I/R-induced lung injury. These cells may exert therapeutic effects through blocking HMGB1 and inflammatory cytokines.


2021 ◽  
Vol 12 (4) ◽  
pp. 2566-2572
Author(s):  
Shubha P ◽  
Shyamsundar S ◽  
Manjunatha H B

COVID-19 pandemic, which has traumatized the world population, in principle, is an inflammatory lung disease secondary to SARS-COV2 virus infection. Inflammatory lung injury progressing to Acute Respiratory Distress Syndrome (ARDS) is a recognized clinical feature of the disease. Inflammatory cytokines released in response to COVID-19 activate the transcription factor - the nuclear factor-қB (NF-қB) and series of pro-inflammatory cytokines, which are responsible for lung injury. Accurate yet precise treatment of coronavirus disease still remains inconclusive, and intervention is mainly symptomatic treatment, respiratory support, antiviral therapies and vaccination. Currently, the major focus of therapy is on reducing lung inflammation by elevating the host immunity. In this scenario, NF-қB inhibition can be conceptualized as a promising approach to down-regulate the overproduction of cytokines, such that inflammatory lung tissue injury could be prevented in COVID-19 infected patients. Towards this, curcumin from Curcuma longa (Turmeric) would play a vital role in the intervention and suppress NF-қB activation via translocation of p65 into the nucleus. Moreover, Curcumin is a proven therapeutic agent against various inflammatory pathologies as it also has the potential to inhibit the expression of certain genes that are critical for the regulation of inflammation.  Keeping this phenomenon and the current medical significance in view, we have explored and computed the anti-inflammatory properties of curcumin to develop it as a potent therapeutic agent to prevent NF-қB induced lung tissue injury in COVID-19 with the main goal of elevating immunity in the post-covid-19 situations as well as in healthy human beings.


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