Endothelial cell-specific anticoagulation reduces inflammation in a mouse model of acute lung injury

Therapeutic efficacy of thrombin-preconditioned mesenchymal stromal cell-derived extracellular vesicles on Escherichia coli-induced acute lung injury in mice

BACKGROUND

Acute lung injury (ALI) following pneumonia involves uncontrolled inflammation and tissue injury, leading to high mortality. We previously confirmed the significantly increased cargo content and extracellular vesicle (EV) production in thrombin-preconditioned human mesenchymal stromal cells (thMSCs) compared to those in naïve and other preconditioning methods. This study aimed to investigate the therapeutic efficacy of EVs derived from thMSCs in protecting against inflammation and tissue injury in an Escherichia coli (E. coli)-induced ALI mouse model.

METHODS

In vitro, RAW 264.7 cells were stimulated with 0.1 µg/mL liposaccharides (LPS) for 1 h, then were treated with either PBS (LPS Ctrl) or 5 × 107 particles of thMSC-EVs (LPS + thMSC-EVs) for 24 h. Cells and media were harvested for flow cytometry and ELISA. In vivo, ICR mice were anesthetized, intubated, administered 2 × 107 CFU/100 µl of E. coli. 50 min after, mice were then either administered 50 µL saline (ECS) or 1 × 109 particles/50 µL of thMSC-EVs (EME). Three days later, the therapeutic efficacy of thMSC-EVs was assessed using extracted lung tissue, bronchoalveolar lavage fluid (BALF), and in vivo computed tomography scans. One-way analysis of variance with post-hoc TUKEY test was used to compare the experimental groups statistically.

RESULTS

In vitro, IL-1β, CCL-2, and MMP-9 levels were significantly lower in the LPS + thMSC-EVs group than in the LPS Ctrl group. The percentages of M1 macrophages in the normal control, LPS Ctrl, and LPS + thMSC-EV groups were 12.5, 98.4, and 65.9%, respectively. In vivo, the EME group exhibited significantly lower histological scores for alveolar congestion, hemorrhage, wall thickening, and leukocyte infiltration than the ECS group. The wet-dry ratio for the lungs was significantly lower in the EME group than in the ECS group. The BALF levels of CCL2, TNF-a, and IL-6 were significantly lower in the EME group than in the ECS group. In vivo CT analysis revealed a significantly lower percentage of damaged lungs in the EME group than in the ECS group.

CONCLUSION

Intratracheal thMSC-EVs administration significantly reduced E. coli-induced inflammation and lung tissue damage. Overall, these results suggest therapeutically enhanced thMSC-EVs as a novel promising therapeutic option for ARDS/ALI.

Heterogeneity of immune cells and their communications unveiled by transcriptome profiling in acute inflammatory lung injury

Background

Acute Respiratory Distress Syndrome (ARDS) or its earlier stage Acute lung injury (ALI), is a worldwide health concern that jeopardizes human well-being. Currently, the treatment strategies to mitigate the incidence and mortality of ARDS are severely restricted. This limitation can be attributed, at least in part, to the substantial variations in immunity observed in individuals with this syndrome.

Methods

Bulk and single cell RNA sequencing from ALI mice and single cell RNA sequencing from ARDS patients were analyzed. We utilized the Seurat program package in R and cellmarker 2.0 to cluster and annotate the data. The differential, enrichment, protein interaction, and cell-cell communication analysis were conducted.

Results

The mice with ALI caused by pulmonary and extrapulmonary factors demonstrated differential expression including Clec4e, Retnlg, S100a9, Coro1a, and Lars2. We have determined that inflammatory factors have a greater significance in extrapulmonary ALI, while multiple pathways collaborate in the development of pulmonary ALI. Clustering analysis revealed significant heterogeneity in the relative abundance of immune cells in different ALI models. The autocrine action of neutrophils plays a crucial role in pulmonary ALI. Additionally, there was a significant increase in signaling intensity between B cells and M1 macrophages, NKT cells and M1 macrophages in extrapulmonary ALI. The CXCL, CSF3 and MIF, TGFβ signaling pathways play a vital role in pulmonary and extrapulmonary ALI, respectively. Moreover, the analysis of human single-cell revealed DCs signaling to monocytes and neutrophils in COVID-19-associated ARDS is stronger compared to sepsis-related ARDS. In sepsis-related ARDS, CD8+ T and Th cells exhibit more prominent signaling to B-cell nucleated DCs. Meanwhile, both MIF and CXCL signaling pathways are specific to sepsis-related ARDS.

Conclusion

This study has identified specific gene signatures and signaling pathways in animal models and human samples that facilitate the interaction between immune cells, which could be targeted therapeutically in ARDS patients of various etiologies.

Endothelial cell dynamics in sepsis-induced acute lung injury and acute respiratory distress syndrome: pathogenesis and therapeutic implications

Sepsis, a prevalent critical condition in clinics, continues to be the leading cause of death from infections and a global healthcare issue. Among the organs susceptible to the harmful effects of sepsis, the lungs are notably the most frequently affected. Consequently, patients with sepsis are predisposed to developing acute lung injury (ALI), and in severe cases, acute respiratory distress syndrome (ARDS). Nevertheless, the precise mechanisms associated with the onset of ALI/ARDS remain elusive. In recent years, there has been a growing emphasis on the role of endothelial cells (ECs), a cell type integral to lung barrier function, and their interactions with various stromal cells in sepsis-induced ALI/ARDS. In this comprehensive review, we summarize the involvement of endothelial cells and their intricate interplay with immune cells and stromal cells, including pulmonary epithelial cells and fibroblasts, in the pathogenesis of sepsis-induced ALI/ARDS, with particular emphasis placed on discussing the several pivotal pathways implicated in this process. Furthermore, we discuss the potential therapeutic interventions for modulating the functions of endothelial cells, their interactions with immune cells and stromal cells, and relevant pathways associated with ALI/ARDS to present a potential therapeutic strategy for managing sepsis and sepsis-induced ALI/ARDS.

YKL-40 promotes chemokine expression following drug-induced liver injury via TF-PAR1 pathway in mice

Background: The inflammatory factor YKL-40 is associated with various inflammatory diseases and is key to remodeling inflammatory cells and tissues. YKL-40 (Chi3l1) promotes the activation of tissue factor (TF), leading to intrahepatic vascular coagulation (IAOC) and liver injury. TF is a key promoter of the exogenous coagulation cascade and is also involved in several signaling involving cell proliferation, apoptosis, charring, migration and inflammatory diseases pathways. However, the effect of YKL-40-induced TF-PAR1 pathway on the expression of downstream chemokines remains unknown. Methods: We established a liver injury model using Concanavalin A (ConA) in C57 BL/6 mice. By adopting various experimental techniques, the effect of YKL-40 induced TF-PAR1 pathway on the expression of downstream chemokine ligand 2 (CCL2) and IP-10 was verified. Results: We found that overexpression of YKL-40 increased the expression of TF, protease-activated receptor 1 (PAR1), CCL2 and IP-10 in mice and exacerbated the severity of liver injury. However, blocking the expression of TF significantly reversed the extent of liver injury. Conclusion: We found that YKL-40 promotes the expression of downstream chemokines ligand 2 (CCL2) and IP-10 by activating the TF-PAR1 pathway, leading to increased recruitment of inflammatory cells and exacerbating the progression of liver injury. This provides a new approach for the clinical treatment of drug-induced liver injury.

Targeting endothelial coagulation signaling ameliorates liver obstructive cholestasis and dysfunctional angiogenesis

Cholestatic fibrogenesis is a pathobiological process in which cumulative injury to the bile ducts coincides with progressive liver fibrosis. The pathobiologic mechanisms underlying fibrogenesis and disease progression remain poorly understood. Currently, there is no effective treatment for liver fibrosis. In this study, we discovered that components of the coagulation cascade were associated with the advanced progression of obstructive cholestasis, and anticoagulant therapy could improve liver cholestasis-induced fibrosis. In a mouse model of common bile duct ligation (BDL), which mimics cholestatic liver injury, RNA sequencing analysis revealed an increased expression of coagulation factors in endothelial cells. Pharmacological targeting of the coagulation signaling by hirudin, an anticoagulatory antagonist of thrombin, ameliorated obstructive cholestasis, and attenuated liver fibrosis symptoms. Hirudin attenuated fibrosis-associated angiogenesis, endothelial-to-mesenchymal transition (EndMT), and tissue hypoxia and reduced liver inflammation after BDL. Furthermore, hirudin suppressed YAP (Yes-associated protein) signaling and its downstream effectors in vascular endothelial cells, which are considered with profibrotic characteristics. In conclusion, we demonstrated that pharmacological targeting of coagulation signaling by hirudin has the potential to alleviate liver obstructive cholestasis and fibrosis.

Ganoderma lucidum polysaccharides ameliorate lipopolysaccharide-induced acute pneumonia via inhibiting NRP1-mediated inflammation

CONTEXT

Ganoderma lucidum polysaccharides (GLP), from Ganoderma lucidum (Leyss. ex Fr.) Karst. (Ganodermataceae), are reported to have anti-inflammatory effects, including anti-neuroinflammation and anti-colitis. Nevertheless, the role of GLP in acute pneumonia is unknown.

OBJECTIVE

To explore the protective role of GLP against LPS-induced acute pneumonia and investigate possible mechanisms.

MATERIALS AND METHODS

GLP were extracted and used for high-performance liquid chromatography (HPLC) analysis after acid hydrolysis and PMP derivatization. Sixty C57BL/6N male mice were randomly divided into six groups: Sham, Model, LPS + GLP (25, 50 and 100 mg/kg/d administered intragastrically for two weeks) and LPS + dexamethasone (6 mg/kg/d injected intraperitoneally for one week). Acute pneumonia mouse models were established by intratracheal injection of LPS. Haematoxylin and eosin (H&E) staining was examined to evaluate lung lesions. ELISA and quantitative real-time PCR were employed to assess inflammatory factors expression. Western blots were carried out to measure Neuropilin-1 expression and proteins related to apoptosis and autophagy.

RESULTS

GLP suppressed inflammatory cell infiltration. In BALF, cell counts were 1.1 × 10⁶ (model) and 7.1 × 10⁵ (100 mg/kg). Release of GM-CSF and IL-6 was reduced with GLP (25, 50 and 100 mg/kg) treatment. The expression of genes IL-1β, IL-6, TNF-α and Saa3 was reduced. GLP treatment also suppressed the activation of Neuropilin-1 (NRP1), upregulated the levels of Bcl2/Bax and LC3 and led to downregulation of the ratio C-Caspase 3/Caspase 3 and P62 expression.

DISCUSSION AND CONCLUSIONS

GLP could protect against LPS-induced acute pneumonia through multiple mechanisms: blocking the infiltration of inflammatory cells, inhibiting cytokine secretion, suppressing NRP1 activation and regulating pneumonocyte apoptosis and autophagy.

Enhanced efficiency of melatonin by stepwise-targeting strategy for acute lung injury

Oxidative stress plays a key role in the progress of acute lung injury (ALI), which is an acute, progressive respiratory failure characterized by alveolar capillary injury caused by various external and internal factors other than cardiogenic factors. Pulmonary vascular endothelial cells are the main target cells during ALI, and therefore the mitochondrial targeting antioxidant derivative triphenylphosphine-melatonin (TPP-MLT) was encapsulated in VCAM-1 antibodies-conjugated nanostructured lipid carriers (VCAM@TPP-MLT NLCs) for lung targeting delivery. VCAM@TPP-MLT NLCs could be preferentially internalized by inflammatory endothelial cells in lung tissues, and then the released TPP-MLT from NLCs effectively eliminated the excessive reactive oxide species (ROS) and ameliorated cell apoptosis. Overall, the results suggested that VCAM@TPP-MLT NLCs exhibited remarkable in vitro and in vivo therapeutic effect on ALI, and could be a promising and efficient strategy for the treatment of ALI.

Network Pharmacology and Experimental Validation to Explore the Mechanism of Qing-Jin-Hua-Tan-Decoction Against Acute Lung Injury

Qing-Jin-Hua-Tan-Decoction (QJHTD), a classic famous Chinese ancient prescription, has been used for treatment of pulmonary diseases since Ming Dynasty. A total of 22 prototype compounds of QJHTD absorbed into rat blood were chosen as candidates for the pharmacological network analysis and molecular docking. The targets from the intersection of compound target and ALI disease targets were used for GO and KEGG enrichment analyses. Molecular docking was adopted to further verify the interactions between 22 components and the top 20 targets with higher degree values in the component–target–pathway network. In vitro experiments were performed to verify the results of network pharmacology using SPR experiments, Western blot experiments, and the PMA-induced neutrophils to produce neutrophil extracellular trap (NET) model. The compound–target–pathway network includes 176 targets and 20 signaling pathways in which the degree of MAPK14, CDK2, EGFR, F2, SRC, and AKT1 is higher than that of other targets and which may be potential disease targets. The biological processes in QJHTD for ALI mainly included protein phosphorylation, response to wounding, response to bacterium, regulation of inflammatory response, and so on. KEGG enrichment analyses revealed multiple signaling pathways, including lipid and atherosclerosis, HIF-1 signaling pathway, renin–angiotensin system, and neutrophil extracellular trap formation. The molecular docking results showed that baicalin, oroxylin A-7-glucuronide, hispidulin-7-O-β-D-glucuronide, wogonoside, baicalein, wogonin, tianshic acid, and mangiferin can be combined with most of the targets, which might be the core components of QJHTD in treatment of ALI. Direct binding ability of baicalein, wogonin, and baicalin to thrombin protein was all micromolar, and their K_D values were 11.92 μM, 1.303 μM, and 1.146 μM, respectively, revealed by SPR experiments, and QJHTD could inhibit Src phosphorylation in LPS-activated neutrophils by Western blot experiments. The experimental results of PMA-induced neutrophils to produce NETs indicated that QJHTD could inhibit the production of NETs. This study revealed the active compounds, effective targets, and potential pharmacological mechanisms of QJHTD acting on ALI.

Long non-coding RNA OIP5-AS1 aggravates acute lung injury by promoting inflammation and cell apoptosis via regulating the miR-26a-5p/TLR4 axis

Background

Acute lung injury (ALI) is a pulmonary disorder that leads to acute respiration failure and thereby results in a high mortality worldwide. Increasing studies have indicated that toll-like receptor 4 (TLR4) is a promoter in ALI, and we aimed to explore the underlying upstream mechanism of TLR4 in ALI.

Methods

We used lipopolysaccharide (LPS) to induce an acute inflammatory response in vitro model and a murine mouse model. A wide range of experiments including reverse transcription quantitative polymerase chain reaction, western blot, enzyme linked immunosorbent assay, flow cytometry, hematoxylin–eosin staining, RNA immunoprecipitation, luciferase activity and caspase-3 activity detection assays were conducted to figure out the expression status, specific role and potential upstream mechanism of TLR4 in ALI.

Result

TLR4 expression was upregulated in ALI mice and LPS-treated primary bronchial/tracheal epithelial cells. Moreover, miR-26a-5p was confirmed to target TLR4 according to results of luciferase reporter assay. In addition, miR-26a-5p overexpression decreased the contents of proinflammatory factors and inhibited cell apoptosis, while upregulation of TLR4 reversed these effects of miR-26a-5p mimics, implying that miR-26a-5p alleviated ALI by regulating TLR4. Afterwards, OPA interacting protein 5 antisense RNA 1 (OIP5-AS1) was identified to bind with miR-26a-5p. Functionally, OIP5-AS1 upregulation promoted the inflammation and miR-26a-5p overexpression counteracted the influence of OIP5-AS1 upregulation on cell inflammatory response and apoptosis.

Conclusion

OIP5-AS1 promotes ALI by regulating the miR-26a-5p/TLR4 axis in ALI mice and LPS-treated cells, which indicates a promising insight into diagnostics and therapeutics in ALI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01589-1.

Hydrogen Attenuates Endotoxin-Induced Lung Injury by Activating Thioredoxin 1 and Decreasing Tissue Factor Expression

Endotoxin-induced lung injury is one of the major causes of death induced by endotoxemia, however, few effective therapeutic options exist. Hydrogen inhalation has recently been shown to be an effective treatment for inflammatory lung injury, but the underlying mechanism is unknown. In the current study we aim to investigate how hydrogen attenuates endotoxin-induced lung injury and provide reference values for the clinical application of hydrogen. LPS was used to establish an endotoxin-induced lung injury mouse model. The survival rate and pulmonary pathologic changes were evaluated. THP-1 and HUVECC cells were cultured in vitro. The thioredoxin 1 (Trx1) inhibitor was used to evaluate the anti-inflammatory effects of hydrogen. Hydrogen significantly improved the survival rate of mice, reduced pulmonary edema and hemorrhage, infiltration of neutrophils, and IL-6 secretion. Inhalation of hydrogen decreased tissue factor (TF) expression and MMP-9 activity, while Trx1 expression was increased in the lungs and serum of endotoxemia mice. LPS-stimulated THP-1 and HUVEC-C cells in vitro and showed that hydrogen decreases TF expression and MMP-9 activity, which were abolished by the Trx1 inhibitor, PX12. Hydrogen attenuates endotoxin-induced lung injury by decreasing TF expression and MMP-9 activity via activating Trx1. Targeting Trx1 by hydrogen may be a potential treatment for endotoxin-induced lung injury.

Neutrophil-Associated Inflammatory Changes in the Pre-Diabetic Pancreas of Early-Age NOD Mice

A growing body of evidence indicates that neutrophils are the first major leukocyte population accumulating inside the pancreas even before the onset of a lymphocytic-driven impairment of functional beta cells in type 1 diabetes mellitus (T1D). In humans, pancreata from T1D deceased donors exhibit significant neutrophil accumulation. We present a time course of previously unknown inflammatory changes that accompany neutrophil and neutrophil elastase accumulation in the pancreas of the non-obese diabetic (NOD) mouse strain as early as 2 weeks of age. We confirm earlier findings in NOD mice that neutrophils accumulate as early as 2 weeks of age. We also observe a concurrent increase in the expression of neutrophil elastase in this time period. We also detect components of neutrophil extracellular traps (NET) mainly in the exocrine tissue of the pancreas during this time as well as markers of vascular pathology as early as 2 weeks of age. Age- and sex-matched C57BL/6 mice do not exhibit these features inside the pancreas. When we treated NOD mice with inhibitors of myeloperoxidase and neutrophil elastase, two key effectors of activated neutrophil activity, alone or in combination, we were unable to prevent the progression to hyperglycemia in any manner different from untreated control mice. Our data confirm and add to the body of evidence demonstrating neutrophil accumulation inside the pancreas of mice genetically susceptible to T1D and also offer novel insights into additional pathologic mechanisms involving the pancreatic vasculature that have, until now, not been discovered inside the pancreata of these mice. However, inhibition of key neutrophil enzymes expressed in activated neutrophils could not prevent diabetes. These findings add to the body of data supporting a role for neutrophils in the establishment of early pathology inside the pancreas, independently of, and earlier from the time at onset of lymphocytic infiltration. However, they also suggest that inhibition of neutrophils alone, acting via myeloperoxidase and neutrophil elastase only, in the absence of other other effector cells, is insufficient to alter the natural course of autoimmune diabetes, at least in the NOD model of the disease.

Construction of a 3A system from BioBrick parts for expression of recombinant hirudin variants III in Corynebacterium glutamicum

Standardized parts can be efficiently assembled into novel biological systems using the three antibiotic (3A) system, ensuring the reusability of components and repeatability of experiments. In this study, we created the 3A expression system for easy construction of gene expression cassettes in Corynebacterium glutamicum (C. glutamicum), which was applied to screen combinations of promoters and signal peptides for improved secreted rhv3 production. We first obtained three strong promoters P₂₂₅₂, P_odhi, and P_yweA from all of promoters, which drive the highest expression of green fluorescent protein (egfp). The three promoters were then assembled with different signal peptides to generate a series of constructs using the 3A expression system developed in this study, from which the highest activity of rhv3 reached 3187.5 ATU/L of P_yweA-CspA-rhv3. Further increased production of rhv3 achieved large-scale fermentation using 5-L jar bioreactor, with the highest rhv3 accumulation 1.21 g/L obtained after 40 h of cultivation, which is higher than 0.95 g/L reported in E. coli. To the best of our knowledge, this is the first report of rhv3 secretory expression in C. glutamicum, which could be applied for the production of other recombinant proteins with significant applications.Key points• We have exploited a 3A system for the genetic manipulation in C. glutamicum.• We constructed element libraries for assembling standard sequence in C. glutamicum.• The secreted expression of rhv3 was realized by 3A system in C. glutamicum.

Evaluation of different commercial antibodies for their ability to detect human and mouse tissue factor by western blotting

BACKGROUND

Western blotting is used to measure protein expression in cells and tissues. Appropriate interpretation of resulting data is contingent upon antibody validation.

OBJECTIVES

We assessed several commercial anti-human and anti-mouse tissue factor (TF) antibodies for their ability to detect TF by western blotting.

MATERIAL AND METHODS

We used human pancreatic cancer cell lines expressing different levels of TF and a mouse pancreatic cancer cell line expressing TF with a matched knockout derivative.

RESULTS

Human and mouse TF protein detected by western blotting correlated with levels of TF mRNA in these cell lines. The apparent molecular weight of TF is increased by N-linked glycosylation and, as expected, deglycosylation decreased the size of TF based on western blotting. We found that four commercial anti-human TF antibodies detected TF in a TF-positive cell line HPAF-II whereas no signal was observed in a TF-negative cell line MIA PaCa-2. More variability was observed in detecting mouse TF. Two anti-mouse TF antibodies detected mouse TF in a TF-positive cell line and no signal was observed in a TF knockout cell line. However, a third anti-mouse TF antibody detected a nonspecific protein in both the mouse TF-positive and TF-negative cell lines. Two anti-human TF antibodies that are claimed to cross react with mouse TF either recognized a nonspecific band or did not detect mouse TF.

DISCUSSION

Our results indicate that there is a range in quality of commercial anti-TF antibodies.

CONCLUSION

We recommend that all commercial antibodies should be validated to ensure that they detect TF.

[Effect of human placental mesenchymal stem cells transplantation on pulmonary vascular endothelial permeability and lung injury repair in mice with acute lung injury]

OBJECTIVE

To investigate the effects of human placental mesenchymal stem cells (hPMSCs) transplantation on pulmonary vascular endothelial permeability and lung injury repair in mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI).

METHODS

The hPMSCs were isolated from the human placental tissue by enzyme digestion and passaged. The cell phenotype of the 3rd generation hPMSCs was detected by flow cytometry. Twenty-four 6-week-old healthy male C57BL/6 mice were randomly divided into 3 groups ( n=8). The mice were instilled with LPS in the airway to prepare an ALI model in the ALI model group and the hPMSCs treatment group, and with saline in the control group. At 12 hours after LPS infusion, the mice were injected with 3rd generation hPMSCs via the tail vein in hPMSCs treatment group and with saline in the ALI model group and the control group. At 24 hours after injection, the lung tissues of all mice were taken. The pathological changes were observed by HE staining. The wet/dry mass ratio (W/D) of lung tissue was measured. The Evans blue leak test was used to detect the pulmonary vascular endothelial permea bility in mice. The expression of lung tissue permeability-related protein (VE-cadherin) was detected by Western blot.

RESULTS

Flow cytometry examination showed that the isolated cells had typical MSCs phenotypic characteristics. Mice in each group survived. The alveolar structure of the ALI model group significantly collapsed, a large number of inflammatory cells infiltrated, and local alveolar hemorrhage occurred; while the alveolar structure collapse of the hPMSCs treatment group significantly improved, inflammatory cells infiltration significantly reduced, and a few red blood cells were in the interstitial lung. W/D and exudation volume of Evans blue stain were significantly higher in the ALI model group than in the control group and the hPMSCs treatment group ( P<0.05), in the hPMSCs treatment group than in the control group ( P<0.05). The relative protein expression of VE-cadherin was significantly lower in the ALI model group than in the control group and the hPMSCs treatment group ( P<0.05), and in the hPMSCs treatment group than in the control group ( P<0.05).

CONCLUSION

Intravenous injection of hPMSCs can effectively reduce the increased pulmonary vascular endothelial permeability mediated by LPS, relieve the degree of lung tissue damage, and play a therapeutic role in ALI mice.

Suppressive Effects of GSS on Lipopolysaccharide-Induced Endothelial Cell Injury and ALI via TNF-α and IL-6

Background. Under septic conditions, LPS induced lung vascular endothelial cell (EC) injury, and the release of inflammatory mediator launches and aggravates acute lung injury (ALI). There are no effective therapeutic options for ALI. Genistein-3'-sodium sulfonate (GSS) is a derivative of native soy isoflavone, which exhibits neuroprotective effects via its antiapoptosis property. However, whether GSS protect against sepsis-induced EC injury and release of inflammatory mediators has not been determined. In this study, we found that GSS not only downregulated the levels of TNF-α and IL-6 in the lung and serum of mice in vivo but also inhibited the expression and secretion of TNF-α and IL-6 in ECs. Importantly, we also found that GSS blocked LPS-induced TNF-α and IL-6 expression in ECs via the Myd88/NF-κB signaling pathway. Taken together, our results demonstrated that GSS might be a promising candidate for sepsis-induced ALI via its regulating effects on inflammatory response in lung ECs.