NF-κB p65 Knock-down inhibits TF, PAI-1 and promotes activated protein C production in lipopolysaccharide-stimulated alveolar epithelial cells type II

Garlic oil supplementation blocks inflammatory pyroptosis-related acute lung injury by suppressing the NF-κB/NLRP3 signaling pathway via H2S generation

Acute lung injury (ALI) is a major cause of acute respiratory failure with a high morbidity and mortality rate, and effective therapeutic strategies for ALI remain limited. Inflammatory response is considered crucial for the pathogenesis of ALI. Garlic, a globally used cooking spice, reportedly exhibits excellent anti-inflammatory bioactivity. However, protective effects of garlic against ALI have never been reported. This study aimed to investigate the protective effects of garlic oil (GO) supplementation on lipopolysaccharide (LPS)-induced ALI models. Hematoxylin and eosin staining, pathology scores, lung myeloperoxidase (MPO) activity measurement, lung wet/dry (W/D) ratio detection, and bronchoalveolar lavage fluid (BALF) analysis were performed to investigate ALI histopathology. Real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay were conducted to evaluate the expression levels of inflammatory factors, nuclear factor-κB (NF-κB), NLRP3, pyroptosis-related proteins, and H2S-producing enzymes. GO attenuated LPS-induced pulmonary pathological changes, lung W/D ratio, MPO activity, and inflammatory cytokines in the lungs and BALF. Additionally, GO suppressed LPS-induced NF-κB activation, NLRP3 inflammasome expression, and inflammatory-related pyroptosis. Mechanistically, GO promoted increased H2S production in lung tissues by enhancing the conversion of GO-rich polysulfide compounds or by increasing the expression of H2S-producing enzymes in vivo. Inhibition of endogenous or exogenous H2S production reversed the protective effects of GO on ALI and eliminated the inhibitory effects of GO on NF-κB, NLRP3, and pyroptotic signaling pathways. Overall, these findings indicate that GO has a critical anti-inflammatory effect and protects against LPS-induced ALI by suppressing the NF-κB/NLRP3 signaling pathway via H2S generation.

Protective role of forsythoside B in Kawasaki disease-induced cardiac injury: Inhibition of pyroptosis via the SIRT1-NF-κB-p65 signaling pathway

Kawasaki disease (KD), an acute exanthematous febrile pediatric illness involving systemic non-specific inflammatory reactions in small- and medium-sized arteries, poses a significant risk of coronary artery and myocardial inflammatory injury. Developing new KD treatments with improved safety and fewer side-effects is highly desirable. Forsythoside B (FTS-B), extracted from the Forsythia suspensa plant, exerts anti-inflammatory activity by inhibiting NF-κB, which is regulated by SIRT1, the reduced expression of which is strongly associated with cardiovascular disease. However, it has yet to be established whether FTS-B influences KD-related inflammatory damage. In this study, we investigated the effects of FTS-B on inflammation in cellular and murine models of KD. Our findings revealed that KD is associated with cardiac dysfunction and inflammatory injury to myocardial and human coronary artery endothelial cells (HCAECs), resulting in a pyroptosis-feedback loop. Both cellular and KD models were characterized by reduced SIRT1 expression and increased NF-κB p65 expression. Contrastingly, the rates of pyroptosis in both murine model myocardial tissues and HCAECs were significantly alleviated in response to FTS-B treatment. Also in both models, we detected an increase of SIRT1 expression and a decrease in the expression of p65. Further examination of the protective mechanism of FTS-B using the SIRT1-specific inhibitor, EX 527, revealed that this inhibitor blocked the palliative effects of FTS-B on inflammatory injury-induced pyroptosis. These results highlight the potential utility of the SIRT1-NF-κB-p65 pathway as a therapeutic target for KD treatment and demonstrate that FTS-B can alleviate KD-induced cardiac and HCAEC inflammatory injury via inhibition of pyroptosis.

mmu-miR-374b-5p modulated inflammatory factors via downregulation of C/EBP β/NF-κB signaling in Kupffer cells during Echinococcus multilocularis infection

BACKGROUND

Alveolar echinococcosis (AE) is an important infectious disease caused by the metacestode larvae of Echinococcus multilocularis, seriously threatening global public health security. Kupffer cells (KCs) play important roles in liver inflammatory response. However, their role in hepatic alveolar echinococcosis has not yet been fully elucidated.

METHODS

In this study, qRT-PCR was used to detect the expression level of miR-374b-5p in KCs. The target gene of miR-374b-5p was identified through luciferase reporter assays and loss of function and gains. Critical genes involved in NFκB signaling pathway were analyzed by qRT-PCR and western blot.

RESULTS

This study reported that miR-374b-5p was significantly upregulated in KCs during E. multilocularis infection and further showed that miR-374b-5p was able to bind to the 3'-UTR of the C/EBP β gene and suppressed its expression. The expression levels of NF-κBp65, p-NF-κBp65 and pro-inflammatory factors including iNOS, TNFα and IL6 were attenuated after overexpression of miR-374b-5p while enhanced after suppression of miR-374b-5p. However, the Arg1 expression level was promoted after overexpression of miR-374b-5p while suppressed after downregulation of miR-374b-5p. Additionally, increased protein levels of NF-κBp65 and p-NF-κBp65 were found in the C/EBP β-overexpressed KCs.

CONCLUSIONS

These results demonstrated that miR-374b-5p probably regulated the expression of inflammatory factors via C/EBP β/NF-κB signaling. This finding is helpful to explore the mechanism of inflammation regulation during E. multilocularis infection.

6-Gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition in LPS-provoked ARDS via RUNX1/NF-κB signaling pathway

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition play a central role in refractory hypoxemia in acute respiratory distress syndrome (ARDS), but it lacks effective drugs for prevention and treatment of this pathophysiology. Our previous experiment confirmed that RUNX1 promoted alveolar hypercoagulation and fibrinolytic inhibition through NF-κB pathway. Other studies demonstrated that 6-gingerol regulated inflammation and metabolism by inhibiting the NF-κB signaling pathway. We assume that 6-gingerol would ameliorate alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/ NF-κB pathway in LPS-induced ARDS.

METHODS

Rat ARDS model was replicated through LPS inhalation. Before LPS inhalation, the rats were intraperitoneally treated with different doses of 6-gingerol or the same volume of normal saline (NS) for 12 h, and then intratracheal inhalation of LPS for 24 h. In cell experiment, alveolar epithelial cell type II (AECII) was treated with 6-gingerol for 6 h and then with LPS for another 24 h. RUNX1 gene was down-regulated both in pulmonary tissue and in cells. Tissue factor (TF), plasminogen Activator Inhibitor 1(PAI-1) and thrombin were determined by Wester-blot (WB), qPCR or by enzyme-linked immunosorbent (ELISA). Lung injury score, pulmonary edema and pulmonary collagen III in rat were assessed. NF-κB pathway were also observed in vivo and in vitro. The direct binding capability of 6-gingerol to RUNX1 was confirmed by using Drug Affinity Responsive Target Stability test (DARTS).

RESULTS

6-gingerol dose-dependently attenuated LPS-induced lung injury and pulmonary edema. LPS administration caused excessive TF and PAI-1 expression both in pulmonary tissue and in AECII cell and a large amount of TF, PAI-1 and thrombin in bronchial alveolar lavage fluid (BALF), which all were effectively decreased by 6-gingerol treatment in a dose-dependent manner. The high collagen Ⅲ level in lung tissue provoked by LPS was significantly abated by 6-gingerol. 6-gingerol was seen to dramatically inhibit the LPS-stimulated activation of NF-κB pathway, indicated by decreases of p-p65/total p65, p-IKKβ/total IKKβ, and also to suppress the RUNX1 expression. RUNX1 gene knock down or RUNX1 inhibitor Ro5-3335 significantly enhanced the efficacies of 6-gingerol in vivo and in vitro, but RUNX1 over expression remarkably impaired the effects of 6-gingerol on TF, PAI-1 and on NF-κB pathway. DARTS result showed that 6-gingerol directly bond to RUNX1 molecules.

CONCLUSIONS

Our experimental data demonstrated that 6-gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/NF-κB pathway in LPS-induced ARDS. 6-gingerol is expected to be an effective drug in ARDS.

Variation in presepsin and thrombomodulin levels for predicting COVID-19 mortality

Coronavirus disease (COVID-19) has caused extensive mortality globally; therefore, biomarkers predicting the severity and prognosis of COVID-19 are essential. This study aimed to evaluate the application of presepsin (P-SEP) and thrombomodulin (TM), which are biomarkers of sepsis and endothelial dysfunction, respectively, in the prognosis of COVID-19. Serum P-SEP and TM levels from COVID-19 patients (n = 183) were measured. Disease severity was classified as mild, moderate I, moderate II, or severe based on hemoglobin oxygen saturation and the history of intensive care unit transfer or use of ventilation at admission. Patients in the severe group were further divided into survivors and non-survivors. P-SEP and TM levels were significantly higher in the severe group than those in the mild group, even after adjusting for creatinine values. In addition, TM levels were significantly higher in non-survivors than in survivors. Changes in the P-SEP levels at two time points with an interval of 4.1 ± 2.2 days were significantly different between the survivors and non-survivors. In conclusion, TM and continuous P-SEP measurements may be useful for predicting mortality in patients with COVID-19. Moreover, our data indicate that P-SEP and TM values after creatinine adjustment could be independent predictive markers, apart from renal function.

Advances in Biomarkers for Diagnosis and Treatment of ARDS

Acute respiratory distress syndrome (ARDS) is a common and fatal disease, characterized by lung inflammation, edema, poor oxygenation, and the need for mechanical ventilation, or even extracorporeal membrane oxygenation if the patient is unresponsive to routine treatment. In this review, we aim to explore advances in biomarkers for the diagnosis and treatment of ARDS. In viewing the distinct characteristics of each biomarker, we classified the biomarkers into the following six categories: inflammatory, alveolar epithelial injury, endothelial injury, coagulation/fibrinolysis, extracellular matrix turnover, and oxidative stress biomarkers. In addition, we discussed the potential role of machine learning in identifying and utilizing these biomarkers and reviewed its clinical application. Despite the tremendous progress in biomarker research, there remain nonnegligible gaps between biomarker discovery and clinical utility. The challenges and future directions in ARDS research concern investigators as well as clinicians, underscoring the essentiality of continued investigation to improve diagnosis and treatment.

Ameliorating effects of berberine on sepsis-associated lung inflammation induced by lipopolysaccharide: molecular mechanisms and preclinical evidence

As a life-threatening disorder, sepsis-associated lung injury is a dysregulated inflammatory response to microbial infection, characterized by the infiltration of inflammatory cells into lung tissues and excessive production of pro-inflammatory mediators. Therefore, immunomodulatory/anti-inflammatory agents are a potential treatment for sepsis-associated lung injury. Berberine, one of the well-studied medicinal plant-derived compounds, has shown promising anti-inflammatory potential in inflammatory conditions, through modulating excessive immune responses induced by various immune cells. A systematic literature search in electronic databases indicated several publications that studied the effect of berberine on lipopolysaccharide (LPS)-induced sepsis in preclinical investigations. The current review article aims to provide evidence on the effects of berberine against LPS-induced acute lung injury (ALI), together with underlying molecular mechanisms. The findings reveal that berberine through inhibiting the excessive production of multiple pro-inflammatory cytokines, suppressing the infiltration of immune cells into lung tissues, as well as preventing pulmonary edema and coagulation, can relieve pulmonary histopathological changes from LPS-mediated inflammation, thereby attenuating sepsis-associated lung injury and lethality in the experimental models. In conclusion, berberine shows great potential as a preventing and therapeutic agent for sepsis-associated lung injury, however, further proof-of-concept studies and clinical investigations are warranted for translating these preclinical findings into clinical practices.

The Mechanism of Chaiyin Particles in the Treatment of COVID-19 Based on Network Pharmacology and Experimental Verification

Objective: To explore the potential active components of Chaiyin particles (CYPs) in the treatment of coronavirus disease 2019 (COVID-19) and their mechanism of action using network pharmacology and molecular docking technology. Methods: Based on the components of CYPs, we obtained potential targets of the interaction between CYPs and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The potential targets were analyzed by protein–protein interaction, gene ontology, and Kyoto Encyclopedia of Genes and Genomes pathway analyses. The key active components of CYPs were subjected to molecular docking with 3-chymotrypsin-like protease, angiotensin-converting enzyme II (ACE2), RNA-dependent RNA polymerase, and papain-like protease. The components that may bind to the key target proteins of SARS-CoV-2 were screened to obtain the potential active components, targets and pathways for CYP treatment of COVID-19. The above-described network analysis results were then verified experimentally. Results: CYPs may prevent and treat COVID-19 by inhibiting the release of inflammatory factors such as IL-6 and TNF-α; participating in the AGE-Rage signaling pathway, the HIF-1 signaling pathway, and other anti-inflammatory, antiviral, and immune regulatory signaling pathways; and blocking ACE2 via fortunellin and baicalin. Conclusion: This work illustrated that CYPs mainly play an anti-inflammatory and immunomodulatory role in COVID-19 prevention and treatment. The potential active components and molecular mechanism of CYPs can provide theoretical support and a pharmacological basis for further development and utilization of CYPs in the prevention and treatment of COVID-19. These results provide important insights into future studies of Traditional Chinese medicines (TCMs) modernization and prevention.

Andrographolide Suppresses Expressions of Coagulation and Fibrinolytic Inhibition-Related Factors in LPS-Induced Alveolar Epithelial Cell Type II via NF-κB Signal Pathway In Vitro

Background

Andrographolide (Andro) has been confirmed to ameliorate alveolar hypercoagulation and fibrinolysis inhibition via NF-κB pathway in acute respiratory distress syndrome (ARDS), but the specific target of Andro is unknown.

Purpose

Our aim is to explore the specific target of Andro through which the drug exerted its effects on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS.

Methods

AECII was treated with different doses of Andro for 1 h, and then stimulated with LPS for 24 h. Expressions of tissue factor (TF), plasminogen activator inhibitor (PAI)-1 and tissue factor pathway inhibitor (TFPI) were detected. Concentrations of thrombin-antithrombin complex (TAT), pro-collagen type III peptide (PIIIP), antithrombin III (ATIII) and activated protein C (APC) in cell supernatant were measured by enzyme linked immunosorbent assay (ELISA). NF-κB signaling pathways activation was simultaneously determined. AECII with p65 down-/over-expression were used as control.

Results

Andro effectively inhibited TF and PAI-1 and promoted TFPI expressions on AECII induced by LPS stimulation. Andro also significantly suppressed the productions of TAT and PIIIP but promoted ATIII and APC secretions from the LPS-treated cell. Furthermore, Andro application obviously inhibited NF-κB signaling pathway activation provoked by LPS, as shown by decreased level of phosphorylation (p‑)-IKKβ/IKKβ, p-p65/p65 and p65 DNA binding activity. The effects of Andro on those factors were obviously strengthened by down- but were weakened by up-regulation of p65 gene in AECII cell.

Conclusions

Our data demonstrates that targeting AECII is the mechanism by which Andro ameliorates alveolar hypercoagulaiton and fibrinolytic inhibition via NF-κB pathway in ARDS. Andro is worth to be clinically further studied in ARDS treatment.

Agomelatine protects heart and aorta against lipopolysaccharide-induced cardiovascular toxicity via inhibition of NF-kβ phosphorylation

The aim of this study was to investigate the possible ameliorating effects of agomelatine (AGO) on lipopolysaccharide (LPS)-induced endothelial and cardiac damage. Twenty-four female Wistar Albino rats divided into 3 groups as follows: Control, LPS and LPS + AGO. Total oxidant status (TOS), total antioxidant status (TAS), nuclear factor kappa beta (NF-kβ)/p65, p-NF-kβ, full caspase-8 (Cas-8) and cleaved cas-8 levels were measured in cardiac tissues and creatine kinase MB (CKMB), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) levels in blood biochemically. In addition; cas-8, sirtuin-1 (SIRT-1), interleukin-4 (IL-4), interleukin-10 (IL-10), haptoglobin measured histopathologically in cardiac and aortic tissues. The levels of CKMB, AST, LDH and TOS were increased and TAS were decreased in the LPS group. In Western blot analyses NF-kβ/p65, p-NF-kβ/p65, full and cleaved cas-8 protein levels increased in cardiac tissues of LPS group. In histopathological and immunohistochemical evaluation of the heart sections; hyperemia, micro-hemorrhages and inflammatory cell infiltrations, increase of cas-8, haptoglobin, IL-4 and IL-10 and decrease of SIRT-1 levels were observed in cardiac and endothelial tissues of LPS groups. AGO treatment reversed all these parameters. It was shown that LPS-induced inflammation, oxidative stress and apoptosis via increasing of NF-kβ/p65 signaling, decreasing of SIRT-1 levels and increase of cas-8 levels in heart and endothelial tissues respectively. AGO corrected all these parameters by its antioxidant, antiinflammatory and antiapoptotic activities.

Andrographolide sulfonate attenuates alveolar hypercoagulation and fibrinolytic inhibition partly via NF-κB pathway in LPS-induced acute respiratory distress syndrome in mice

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition are important characteristics during acute respiratory distress syndrome (ARDS), and NF-κB p65 signaling pathway is involved to regulate these pathophysiologies. We hypothesize that targeting NF-κB signal pathway could ameliorate alveolar hypercoagulation and fibrinolyitc inhibition, thus attenuating lung injury in ARDS.

PURPOSE

We explore the efficacy and the potential mechanism of andrographolide sulfonate (Andro-S) on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS in mice.

METHODS

ARDS was made by lipopolysaccharide (LPS) inhalation in C57BLmice. Andrographolide sulfonate (2.5, 5 and 10 mg/kg) was intraperitoneally given to the mice (once a day for three consecutive days) before LPS administration. NEMO binding domain peptide (NBD), an inhibitor of NF-κB, was used as the positive control and it replaced Andro-S in mice of NBD group. Mice in normal control received saline instead of LPS. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected for analysis of alveolar coagulation, fibrinolytic inhibition as well as of pulmonary inflammatory response after 8 h of LPS inhalation. NF-κB signal pathway in lung tissue was simultaneously determined.

RESULTS

Andro-S dose-dependently inhibited tissue factor (TF) and plasminogen activator inhibitor (PAI)-1 expressions either in mRNA or in protein in lung tissue of ARDS mice, and it also decreased the concentrations of TF, PAI-1, thrombin-antithrombin complex (TAT), procollagen peptide type Ⅲ (PⅢP) while promoting the production of activated protein C (APC) in BALF. Meanwhile, Andro-S effectively inhibited inflammatory response (interleukin 1β and myeloperoxidase) induced by LPS. LPS stimulation dramatically activated NF-κB signal pathway, indicated by increased expressions of phosphorylation of p65 (p-p65), p-IKKα/β and p-IκBα and the higher p65-DNA binding activity, which were all dose-dependently reversed by Andro-S. Andro-S and NBD presented similar efficacies.

CONCLUSIONS

Andro-S treatment improves alveolar hypercoagulation and fibrinolytic inhibition and attenuates pulmonary inflammation in LPS-induced ARDS in mice partly through NF-κB pathway inactivation. The drug is expected to be an effective choice for ARDS.

LncRNA NEAT1 aggravates lipopolysaccharide-induced acute lung injury by regulating the miR-98-5p/TLR4 axis

Although long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) was reported to be associated with acute lung injury (ALI), its specific mechanism has not been well studied. Mouse and cell ALI models were constructed by lipopolysaccharide (LPS). Cell viability was evaluated by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide assay. Cell death was evaluated by lactate dehydrogenase release (LDH) detection kit and flow cytometry. The levels of cytokines in lung tissues lysates were detected by quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). The expression of apoptosis-related markers was detected by Western blot. The relationship between NEAT1, miR-98-5p, and toll-like receptor 4 (TLR4) was determined by bioinformatics prediction, luciferase reporter assay, and RNA immunoprecipitation (RIP) assay. Rescue experiments were performed to determine the role of NEAT1/miR-98-5p/TLR4 in ALI. NEAT1 was significantly upregulated during ALI both in vitro and in vivo. NEAT1 knockdown efficiently attenuated LPS-induced ALI and reduced LPS-induced elevation of cytokines both in vitro and in vivo. NEAT1 negatively regulated miR-98-5p by directly sponging it, and TLR4 was a target of miR-98-5p. MiR-98-5p inhibition or TLR4 overexpression could obviously attenuate the protective effects of NEAT1 knockdown in LPS-treated A549 cells. Our study demonstrated that NEAT1 knockdown alleviated LPS-induced ALI by targeting the miR-98-5p/TLR4 axis.

MiR-494-mediated Effects on the NF-κB Signaling Pathway Regulate Lipopolysaccharide-Induced Acute Kidney Injury in Mice

OBJECTIVE

To explore the effects of miR-494 inhibition through the NF-κB signaling pathway on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) mouse model.

METHODS

The AKI mice induced by LPS were treated with miR-494 antagomir, and the kidney parameters and indicators of oxidative stress were detected. HE and TUNEL staining were performed to observe the kidney histopathology and the apoptosis in renal tubular epithelial cells (RTECs), respectively. The ROS level was measured using dihydroethidium (DHE) staining. In addition, qRT-PCR, western blotting, immunohistochemistry (IHC), and ELISA were also used to detect gene or protein expression.

RESULTS

LPS-induced AKI mice injected with the miR-494 antagomir showed reduced blood urea nitrogen (BUN) and serum creatinine (Cr) with improved kidney histopathology. The expression levels of p-IKKα/β, p-IκBα and p65 NF-κB in the nucleus were increased in kidney tissues from the LPS-induced AKI mice, and they were decreased by the miR-494 antagomir. Moreover, the results of IHC showed that the miR-494 antagomir downregulated p65 NF-κB in kidney tissues from the LPS-induced AKI mice, accompanied by decreased levels of TNF-α, IL-1β, IL-6, MDA, NO, and ROS but increased levels of SOD and GSH. In addition, the LPS-induced AKI mice had increased apoptosis in RTECs, as well as increased Caspase-3 and Bax and decreased Bcl-2, which were reversed by the miR-494 antagomir.

CONCLUSIONS

The inhibition of miR-494 could reduce inflammatory responses and improve oxidative stress in kidney tissues from LPS-induced AKI mice by blocking the NF-κB pathway accompanying by reduced apoptosis in RTECs.

Identifying the molecular targets and mechanisms of xuebijing injection for the treatment of COVID-19 via network parmacology and molecular docking

Xuebijing Injection have been found to improve the clinical symptoms of COVID-19 and alleviate disease severity, but the mechanisms are currently unclear. This study aimed to investigate the potential molecular targets and mechanisms of the Xuebijing injection in treating COVID-19 via network pharmacology and molecular docking analysis. The main active ingredients and therapeutic targets of the Xuebijing injection, and the pathogenic targets of COVID-19 were screened using the TCMSP, UniProt, and GeneCard databases. According to the ‘Drug-Ingredients-Targets-Disease’ network built by STRING and Cytoscape, AKT1 was identified as the core target, and baicalein, luteolin, and quercetin were identified as the active ingredients of the Xuebijing injection in connection with AKT1. R language was used for enrichment analysis that predict the mechanisms by which the Xuebijing injection may inhibit lipopolysaccharide-mediated inflammatory response, modulate NOS activity, and regulate the TNF signal pathway by affecting the role of AKT1. Based on the results of network pharmacology, a molecular docking was performed with AKT1 and the three active ingredients, the results indicated that all three active ingredients could stably bind with AKT1. These findings identify potential molecular mechanisms by which Xuebijing Injection inhibit COVID-19 by acting on AKT1.

Triptolide dose-dependently improves LPS-induced alveolar hypercoagulation and fibrinolysis inhibition through NF-κB inactivation in ARDS mice

BACKGROUND

Alveolar hypercoagulation and fibrinolysis inhibition were associated with the refractory hypoxemia and the high mortality in patient with acute respiratory distress syndrome (ARDS), and NF-κB pathway was confirmed to contribute to the process. Triptolide (TP) significantly inhibited NF-κB pathway and thus depressed accessive inflammatory response in ARDS. We speculate that TP could improve alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS via NF-κB inactivation.

PURPOSE

The aim of this experiment was to explore the efficacy and potential mechanism of TP on alveolar hypercoagulation and fibrinolysis inhibition in LPS-induced ARDS in mice.

METHODS

50 μl of LPS (5 mg/ml) was inhalationally given to C57BL/6 mice to set up ARDS model. Male mice were randomly accepted with LPS, LPS + TP (1 μg/kg, 10 μg/kg, 50 μg/kg respectively), or with NEMO Binding domain peptide (NBD), an inhibitor of NF-κB. TP (1 μg/kg, 10 μg/kg, 50 μg/kg) were intraperitoneally injected or 10 μg/50 μl of NBD solution were inhaled 30 min before LPS inhalation. A same volume of normal saline (NS) substituted for TP in mice in control. The endpoint of experiment was at 8 hours after LPS stimulation. Pulmonary tissues were taken for hematoxylin-eosin (HE) staining, wet / dry ratio and for lung injury scores (LIS). Tissue factor (TF) and plasminogen activator inhibitor (PAI)-1 in lung tissue were detected by Western-blotting and by quantitative Real-time PCR(qPCR) respectively. Concentrations of TF, PAI-1, thrombin-antithrombin complex (TAT), procollagen peptide type Ⅲ (PⅢP) and activated protein C (APC) in bronchoalveolar lavage fluid (BALF) were measured by ELISA. NF-κB activation and p65-DNA binding activity in pulmonary tissue were simultaneously determined.

RESULTS

LPS stimulation resulted in pulmonary edema, neutrophils infiltration, obvious alveolar collapse, interstitial congestion, with high LIS, which were all dose-dependently ameliorated by Triptolide. LPS also dramatically promoted the expressions of TF and PAI-1 either in mRNA or in protein in lung tissue, and significantly stimulated the secretions of TF, PAI-1, TAT, PⅢP but inhibited APC production in BALF, which were all reversed by triptolide treatment in dose-dependent manner. TP dose-dependently inhibited the activation of NF-κB pathway induced by LPS, indicated by the changes of phosphorylations of p65 (p-p65), p-IKKα/β and p-IκBα, and weakened p65-DNA binding activity. TP and NBD had same efficacies either on alveolar hypercoagulation and fibrinolysis inhibition or on NF-κB signalling pathway in ARDS mice.

CONCLUSIONS

TP dose-dependently improves alveolar hypercoagulation and fibrinolysis inhibition in ARDS mice through inhibiting NF-κB signaling pathway. Our data demonstrate that TP is expected to be an effective selection in ARDS.

The fibrinolytic system in the cornea: A key regulator of corneal wound healing and biological defense

The cornea is a relatively unique tissue in the body in that it possesses specific features such as a lack of blood vessels that contribute to its transparency. The cornea is supplied with soluble blood components such as albumin, globulin, and fibrinogen as well as with nutrients, oxygen, and bioactive substances by diffusion from aqueous humor and limbal vessels as well as a result of its exposure to tear fluid. The healthy cornea is largely devoid of cellular components of blood such as polymorphonuclear leukocytes, monocytes-macrophages, and platelets. The location of the cornea at the ocular surface renders it susceptible to external insults, and its avascular nature necessitates the operation of healing and defense mechanisms in a manner independent of a direct blood supply. The fibrinolytic system, which was first recognized for its role in the degradation of fibrin clots in the vasculature, has also been found to contribute to various biological processes outside of blood vessels. Fibrinolytic factors thus play an important role in biological defense of the cornea. In this review, we address the function of the fibrinolytic system in corneal defense including wound healing and the inflammatory response.

Analyzing the potential therapeutic mechanism of Huashi Baidu Decoction on severe COVID-19 through integrating network pharmacological methods

Background and aim

Huashi Baidu Decoction (HSBD) is a novel complex prescription which has positive effects on severe COVID-19. This study was aimed to discover key Chinese materia medica, main active compounds, hub therapeutic target proteins and core signal pathways in the potential therapeutic mechanism of HSBD on severe COVID-19 through integrating network pharmacological methods.

Experimental procedure

TCMSP, TCMID and STITCH databases were used to screen out active compounds and target proteins of HSBD. GeneCards database was used to screen out disease genes of severe COVID-19. The potential therapeutic targets of HSBD on severe COVID-19 were used to construct protein-protein interaction network through STRING database and the hub target proteins were discovered. Next, GO and KEGG enrichment analysis were carried out to discover core signal pathways. Finally, the network diagram of “Chinese materia medica-active compounds-therapeutic target proteins” was built, then key Chinese materia medica and main active compounds were selected.

Results and conclusion

HSBD might treat severe COVID-19 through 45 potential target genes, among them, there were 13 hub target genes: RELA, TNF, IL6, IL1B, MAPK14, TP53, CXCL8, MAPK3, MAPK1, IL4, MAPK8, CASP8, STAT1. Meanswhile, GO_BiologicalProcess and KEGG signaling pathways analysis results showed that the core signal pathways were inflammation and immune regulation pathways. Finally, 4 key Chinese materia medica and 11 main active compounds were discovered in the HSBD. In conclusion, the therapeutic mechanism of HSBD on severe COVID-19 might involve its pharmacological effects of anti-inflammation and immune regulation via acting on 45 disease-related proteins of severe COVID-19.

Taxonomy (classification by evise)

Viral Pneumonia, COVID-19, Acute Respiratory Distress Syndrome, Septic Shock, Chinese Herbal Medicine.

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The potential therapeutic mechanisms of HSBD on severe COVID-19 are demonstrated.

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Anti-inflammation and immune regulation are the main therapeutic mechanisms.

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Multi-target therapy is a promising treatment strategy to cure severe COVID-19.

BAY11-7082 inhibits the expression of tissue factor and plasminogen activator inhibitor-1 in type-II alveolar epithelial cells following TNF-α stimulation via the NF-κB pathway

Pulmonary inflammation strongly promotes alveolar hypercoagulation and fibrinolytic inhibition. NF-κB signaling regulates the expression of molecules associated with coagulation and fibrinolytic inhibition in type-II alveolar epithelial cells (AECII) stimulated by lipopolysaccharide. However, whether TNF-α-induced alveolar hypercoagulation and fibrinolysis inhibition is also associated with the NF-κB pathway remains to be determined. The aim of the present study was to determine whether BAY11-7082, an inhibitor of the NF-κB pathway, inhibits the expressions of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) in AECⅡ in response to TNF-α. Rat AECII were treated with BAY11-7082 for 24 h and stimulated with TNF-α for 1 h. The expression of TF and PAI-1 were determined using western blotting and reverse transcription-quantitative PCR. The concentrations of TF and PAI-1 in culture supernatant were also measured by ELISA. Moreover, levels of NF-κB p65 (p65), phosphorylated (p)-p65 (p-p65), inhibitor of NF-κB α (IκBα) and p-IκBα were also evaluated. Immunofluorescence was used to detect p65 levels in cell nuclei. TNF-α significantly promoted TF and PAI-1 expression either at the mRNA or protein level in AECII cells. Concentrations of TF and PAI-1 in supernatant also significantly increased upon TNF-α stimulation. Furthermore, TNF-α upregulated the levels of p-IκBα, p65, and p-p65 in the cytoplasm. Immunofluorescence analysis indicated that TNF-α increased p65 translocation from the cytoplasm to the nucleus. However, AECII pre-treated with BAY11-7082 expressed lower levels of TF and PAI-1 following TNF-α treatment. Levels of p-IκBα, p65 and p-p65 in the cytoplasm also decreased, and translocation of p65 from cytoplasm into the nucleus was inhibited by BAY11-7082 pretreatment. These findings suggest that BAY11-7082 improves the hypercoagulation and fibrinolytic inhibition induced by TNF-α in alveolar epithelial cells via the NF-κB signaling pathway. BAY11-7082 might represent a therapeutic option for alveolar hypercoagulation and fibrinolytic inhibition in acute respiratory distress syndrome.

Prothrombotic effects of high uric acid in mice via activation of MEF2C-dependent NF-κB pathway by upregulating let-7c

Serum uric acid is reportedly associated with thrombosis development. However, still unclear is the mechanism of high uric acid in thrombosis with the involvement of let-7c. In an aim to fill this void, we conducted this study by treating mice and human umbilical vein endothelial cells with high uric acid. Analysis indicated that let-7c was upregulated in hyperuricemia patients as well as in mice and human umbilical vein endothelial cells treated with high uric acid. Furthermore, high uric acid inhibited myocyte enhancer factor-2C, but activated nuclear factor-kappa B pathway in human umbilical vein endothelial cells. Then the targeting relationship between let-7c and myocyte enhancer factor-2C was verified. On the one hand, high uric acid shortened activated partial thromboplastin time and prothrombin time of mice and declined tissue plasminogen activator level. Additionally, the treatment prolonged thrombin time and elevated the levels of thrombosis related molecules or proteins such as Fibrinogen and D-dimer. Nevertheless, these alternations could be reversed by inhibition of let-7c and nuclear factor-kappa B pathway or overexpressing myocyte enhancer factor-2C. To sum up, our results uncovered the pro-thrombotic effect of high uric acid in mice by activating myocyte enhancer factor-2C-dependent nuclear factor-kappa B pathway via let-7c upregulation.

Emodin improves alveolar hypercoagulation and inhibits pulmonary inflammation in LPS-provoked ARDS in mice via NF-κB inactivation

BACKGROUND

Alveolar hypercoagulation and pulmonary inflammation are important characteristics and they regulate each other in acute respiratory distress syndrome (ARDS). NF-κB pathway has been confirmed to be involved in regulation of this crosstalk. Emodin, a traditional Chinese herb, shows potent inhibitory effect on NF-κB pathway, but whether it is effective in alveolar hypercoagulation and pulmonary inflammation in ARDS remains to be elucidated.

PURPOSE

The aim of this experiment was to evaluate the efficacy of emodin on LPS-provoked alveolar hypercoagulation and excessive pulmonary inflammation in ARDS, and its potential mechanism.

METHODS

Mice ARDS was set up through LPS (40 μl, 4 mg/ml) inhalation. Male mice were randomly received with BPS, LPS only, LPS+ emodin (5 mg/kg, 10 mg/kg, 20 mg/kg, respectively) and BAY65-1942, an inhibitor of IKKβ. After 48 h of LPS stimulation, pulmonary pathological injury, expressions of Tissue factor (TF), plasminogen activator inhibitor (PAI)-1, activated protein C (APC), collagen Ⅰ, collagen III, interleukin (IL) 8, IL-1β and tumor necrosis factor (TNF)-α in lung tissues, as well as concentrations of antithrombin III (AT III), procollagen peptide type III (PIIIP), soluble thrombomodulin (sTM), thrombin antithrombin complex (TAT), myeloperoxidase (MPO) and the percentage of inflammatory cells in bronchoalveolar lavage fluid (BALF) were all determined. NF-κB pathway activation as well as NF-κB DNA binding activity in pulmonary tissue were simultaneously checked.

RESULTS

LPS stimulation resulted in obvious lung injury, excessive inflammatory cells infiltration, which all were dose-dependently ameliorated by emodin. Expressions of TF, PAI-1, collagen Ⅰ and collagen III as well as IL-8, IL-1β and TNF-α in pulmonary tissue were all elevated while APC decreased under LPS provocation, which were all reversed by emodin treatment in dose-dependent manner. LPS promoted the secretions of PIIIP, sTM, TAT and inhibited AT III production in BALF, and resulted in high levels of MPO and the percentage of inflammatory cells in BALF, all of which were significantly and dose-dependently attenuated while AT III production was increased by emodin. Meanwhile, emodin effectively inhibited NF-κB pathway activation and attenuated p65 DNA binding activity induced by LPS inhalation. Emodin and BAY-65-1942 had similar impacts in this experiment.

CONCLUSIONS

Emodin improves alveolar hypercoagulation and fibrinolytic inhibition and depresses excessive pulmonary inflammation in ARDS mice in dose-dependent manner via NF-κB inactivation. Our data demonstrate that emodin is expected to be an effective drug in alveolar hypercoagulation and pulmonary inflammation in ARDS.

SN50 attenuates alveolar hypercoagulation and fibrinolysis inhibition in acute respiratory distress syndrome mice through inhibiting NF-κB p65 translocation

Background

It has been confirmed that NF-κB p65 signaling pathway is involved in the regulation of alveolar hypercoagulation and fibrinolysis inhibition in acute respiratory distress syndrome (ARDS). Whether SN50, a NF-κB cell permeable inhibitor, could attenuate alveolar hypercoagulation and fibrinolysis inhibition in ARDS remains to be elucidated.

Purpose

We explored the efficacy and potential mechanism of SN50 on alveolar hypercoagulation and fibrinolysis inhibition in ARDS in mice.

Materials and methods

Mouse ARDS was made by 50 μl of lipopolysaccharide (LPS) (4 mg/ml) inhalation. Male BALB/c mice were intraperitoneally injected with different does of SN50 1 h before LPS inhalation. Lung tissues were collected for hematoxylin-eosin (HE) staining, wet/dry ratio. Pulmonary expressions of tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1), collagen III, as well as phosphorylated p65 (p-p65), p65 in nucleus (p’-p65), IκBα and IKKα/β were measured. Bronchoalveolar lavage fluid (BALF) was gathered to test the concentrations of TF, PAI-1, activated protein C (APC) and thrombinantithrombin complex (TAT). DNA binding activity of NF-κB p65 was also determined.

Results

After LPS stimulation, pulmonary edema and exudation and alveolar collapse occured. LPS also stimulated higher expressions of TF and PAI-1 in lung tissues, and higher secretions of TF, PAI-1, TAT and low level of APC in BALF. Pulmonary collagen III expression was obviously enhanced after LPS inhalation. At same time, NF-κB signaling pathway was activated with LPS injury, shown by higher expressions of p-p65, p’-p65, p-IKKα/β, p-Iκα in pulmonary tissue and higher level p65 DNA binding activity. SN50 dose-dependently inhibited TF, PAI-1 and collagen IIIexpressions, and decreased TF, PAI-1, TAT but increased APC in BALF. SN50 treatment attenuated pulmonary edema, exudation and reduced lung tissue damage as well. SN50 application significantly reduced p’-p65 expression and weakened p65 DNA binding activity, but expressions of p-p65, p-IKKα/β, p-Iκα in cytoplasm of pulmonary tissue were not affected.

Conclusions

SN 50 attenuates alveolar hypercoagulation and fibrinolysis inhibition in ARDS via inhibition of NF-κB p65 translocation. Our data demonstrates that NF-κB p65 pathway is a viable new therapeutic target for ARDS treatment.

Novel insights into the role of LRRC8A in ameliorating alveolar fluid clearance in LPS induced acute lung injury

Leucine-rich repeat-containing 8A (LRRC8A) protein was recently identified as an essential component of volume-regulated anion channel which plays a central role in maintaining cell volume. The aim of this study was to elucidate the role of LRRC8A in alveolar fluid clearance (AFC) and the effect of inflammatory cytokines on LRRC8A and the underlying mechanism. Lipopolysaccharide (LPS) was used to generate a rat acute lung injury model. The results showed that the concentrations of IL-1β, TNF-α and IL-6 in bronchoalveolar lavage fluid increased significantly, but the expression of LRRC8A in the lung tissue decreased dramatically in the acute lung injury group followed by a decline in the AFC rate. Additionally, LRRC8A knockdown reduced AFC in normal rats. However, specific overexpression of LRRC8A in the lung could increase AFC. Furthermore, we observed the effects of LPS, IL-1β, TNF-α and IL-6 on the LRRC8A current in alveolar type II (ATII) cells, and IL-1β showed the greatest inhibition among them, which was involved in phospho-p38 activation. Overall, LRRC8A plays an essential role in the progression of AFC in LPS-induced acute lung injury, and chronic treatment with IL-1β or TNF-α could inhibit the function of LRRC8A in ATII cells by targeting phospho-p38. All of the findings suggested that LRRC8A could be a new partner in AFC and a potential target for the treatment of acute lung injury.