Ulinastatin Protects Against LPS-Induced Acute Lung Injury By Attenuating TLR4/NF-κB Pathway Activation and Reducing Inflammatory Mediators

Investigation of the anti-inflammatory, anti-oxidant and anti-apoptotic activity of 18β- glycyrrhetinic-acid on the model of LPS-induced lung injury in rats

INTRODUCTION

Our aim was to investigate the protective effects of 18β-Glycyrrhetinic-acid (50 and 100 mg/kg i.g) on LPS-induced rat sepsis model by analyzing some immune mechanisms including inflammation, apoptosis, and oxidative stress parameters by different techniques such as Mallory's Trichome staining, ELISA, tissue biochemistry and Western Blotting.

METHODS

Forty-eight Sprague Dawley rats divided into 6 groups as follows: (i) Control, (ii) DMSO, (iii) LPS induced-Sepsis, (iv) LPS induced-Sepsis+ 18β-GA 50 mg/kg, (v) LPS induced-Sepsis + 18β-GA 100 mg/kg, (vi) 18β-GA 100 mg/kg. The pro-inflammatory cytokine (IFNγ, IL-1ß, TNF- α) levels were measured by ELISA technique. All rat's lung tissues micrographed with Mallory's Trichome stain. Oxidative stress parameters (MDA, GSH, SOD, NRF2, and HO-1), TLR4 signaling, and apoptotic proteins (Bcl-2 and Caspase-3) were detected by using tissue biochemistry and Western blotting.

RESULTS

LPS administration caused a significant increase in all pro-inflammatory cytokine and oxidant levels. Shedding of bronchiolar epithelium, thickening of alveolar septa and vascular dilatation in LPS groups' lung tissue were revealed according to the histopathological findings. The H-scores of 18β-GA50 +LPS and 18β-GA100 +LPS groups were significantly lower than LPS groups' (p < 0.05). When lung tissue protein expression profiles were analyzed for HO-1, TLR4, IL-1β, TNF-α, Bcl-2, and Caspase-3 expression was higher in the LPS group than in the control. In addition, NRF2 and Bcl-2 protein expressions were higher in control, DMSO and 18β-GA100 groups, while it was the lowest level in LPS group.

CONCLUSION

18β-GA demonstrates significant protective effects against LPS-induced lung injury in rats by modulating various immune mechanisms. These findings indicate that 18β-GA, particularly at the higher dose, may be a potential therapeutic agent in managing sepsis by mitigating inflammation, oxidative stress, and apoptosis in lung tissue. The inflammation and oxidative stress parameters were decreased and the apoptotic markers were increased in treatment group. Further molecular studies should be performed to investigate the roles of some significant cellular signaling pathways.

Discussion of the material basis for prevention and treatment of pulmonary fibrosis using naturally medicinal and edible homologous herbs based on the dynamic process of Nrf2, NF-κB and TGF-β in PF

Pulmonary fibrosis (PF) is a progressive chronic lung disease with a high incidence and poor prognosis. Despite extensive research into the mechanisms that initiate and drive the progression of pulmonary fibrosis, developing effective treatments remains challenging due to the multiple etiologies, pathogenic links, and signaling pathways involved in PF. Indeed, nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear factor kappa-B (NF-κB), and transforming growth factor-beta (TGF-β) are central players in the pathogenesis of pulmonary fibrosis, and each of these factors influences distinct yet interconnected processes that collectively contribute to disease progression: Nrf2 upregulates antioxidants to mitigate oxidative stress, NF-κB modulates inflammatory responses, and TGF-β promotes fibroblast activation and extracellular matrix (ECM) deposition, leading to fibrosis. Targeting these pathways may offer therapeutic strategies, uncover new insights and provide potential therapeutic targets for PF. Absolutely, the interactions between Nrf2, NF-κB, and TGF-β pathways are complex and can significantly influence the progression of PF, which indicated that targeting a single pathway may show poor efficacy in managing the condition. Moreover, few therapies that effectively intervene in these pathways have been approved. This review focused on the molecular mechanisms of Nrf2, NF-κB, and TGF-β involving in PF and the material basis of the naturally medicinal and edible homologous herbs, which provides a solid foundation for understanding the disease's pathogenesis, and supports the development of therapeutic drugs or treatments for addressing the complex nature of PF.

The Protective Effects of a Single Dose Myricetin Application on CLP-Induced Rat Sepsis Model by Analyzing Some Immune Mechanisms

INTRODUCTION

In this study, our aim was to investigate the protective effects of myricetin (single dose-100 mg/kg) on CLP-induced rat sepsis model by analyzing some immune mechanisms including inflammation and oxidative stress by different techniques such as Immunohistochemistry, ELISA, tissue biochemistry and Western Blotting.

METHODS

Twenty-eight Wistar albino rats were divided into 4 groups. The pro-inflammatory and anti-inflammatory cytokine levels were measured by ELISA technique. CD68 and Nuclear-Factor-Kappa-B (NF-κB) positivity rates were detected by IHC. Some of oxidative stress parameters were measured by tissue biochemistry, while Toll-lke Receptor-4 (TLR4) expression others were detected by Western blot technique.

RESULTS

Sepsis caused a significant increase in all pro-inflammatory cytokine and oxidant levels. Also, it led to an increase in the positivity of CD68 and NF-κB markers as well as the expression levels of TNF-alpha, IL-1-beta, TLR4, Keap-1. However, single dose myricetin application normalized pro-inflammatory cytokine levels, increased anti-oxidant and anti-inflammatory cytokine levels, decreased positivity of CD68 and NF-κB and increased NRF2 and HO-1 expressions.

DISCUSSION

As a conclusion, the beneficial effect of myricetin on lung injury also involved inhibition of TLR4/NF-κB pathway, suppression of proinflammatory cytokines and induction of anti-inflammatory cytokine production, regulation of oxidant and anti-oxidant system parameters, and activating the NRF2/Keap1/HO-1 pathway.

Neutrophil membrane-coated nanoparticles for targeted delivery of toll-like receptor 4 siRNA ameliorate LPS-induced acute lung injury

Pulmonary delivery of small interfering RNAs (siRNAs) is an effective treatment for acute lung injury (ALI), which can modulate the expression of pro-inflammatory cytokines and alleviate the symptoms of ALI. However, the rapid degradation of siRNA in vivo and its limited ability to target and validate cells are important challenges it faces in clinical practice. In this work, we developed neutrophil membrane-coated Poly (lactic-co-glycolic acid) nanoparticles loaded with TLR4 siRNA (si-TLR4) (Neutrophil-NP-TLR4), which can target both inflammatory and macrophage cells to alleviate the pulmonary inflammation in lipopolysaccharide (LPS)-induced ALI mice. These Neutrophil-NP-TLR4 effectively reduce the TNF-α and IL-1β expressions both in vitro and in vivo. Meanwhile, they also reduced the expression of TLR4, and its downstream genes including TNF receptor-associated factor 6 (TRAF6), X-linked inhibitor of apoptosis protein (XIAP), and Nuclear Factor kappa-B (NF-κB), but elevated the levels of Aquaporin 1 (AQP1) and Aquaporin 5 (AQP5). Moreover, the Neutrophil-NP-TLR4 precisely targets the inflammatory site to attenuate the lung injury without causing toxicity to normal tissue. This system provides a promising approach to effective delivery of siRNA to precisely treat the ALI.

Echinacoside attenuates Klebsiella pneumoniae-induced pneumonia via inhibition of the TLR4/NF-κB signaling

The Gram-negative bacterium Klebsiella pneumoniae (K. pneumoniae) is one major causative agent of community- and hospital-acquired pneumonia. Echinacoside (ECH) is a phenylethanoid glycoside isolated from Cistanche deserticola that possesses anti-inflammatory activity. Our research aimed to confirm whether ECH alleviates K. pneumoniae-induced pneumonia and explore the underlying regulatory mechanisms. BEAS-2B cells and BALB/c mice were infected by K. pneumoniae to establish the cellular and animal models, respectively, followed by ECH treatment. Inflammatory cytokine levels were detected by RT-qPCR and ELISA. The lung wet/dry (W/D) weight ratio and the myeloperoxidase (MPO) activity in lung tissues were examined. The pulmonary histopathologic changes were observed through hematoxylin and eosin (H&E) staining. The levels of TLR4/NF-κB pathway-associated molecules were estimated through western blotting, immunohistochemical, and immunohistochemical staining. K. pneumoniae infection caused lung histopathologic damage, enhanced MPO activity, elevated lung W/D weight ratio, and upregulated inflammatory cytokine levels in mice and promoted inflammatory cytokine expression in BEAS-2B cells, which were reversed by ECH treatment. K. pneumoniae infection-induced upregulation in TLR4, phosphorylated (p)-p65, and p-IκBα levels, and downregulation in IκBα levels in BEAS-2B cells and pneumonia mice were overturned by ECH treatment. ECH ameliorates K. pneumoniae-induced pneumonia through suppressing the TLR4/NF-κB pathway.

Metformin reprograms tryptophan metabolism via gut microbiome-derived bile acid metabolites to ameliorate depression-Like behaviors in mice

As an adjunct therapy, metformin enhances the efficacy of conventional antidepressant medications. However, its mode of action remains unclear. Here, metformin was found to ameliorate depression-like behaviors in mice exposed to chronic restraint stress (CRS) by normalizing the dysbiotic gut microbiome. Fecal transplants from metformin-treated mice ameliorated depressive behaviors in stressed mice. Microbiome profiling revealed that Akkermansia muciniphila (A. muciniphila), in particular, was markedly increased in the gut by metformin and that oral administration of this species alone was sufficient to reverse CRS-induced depressive behaviors and normalize aberrant stress-induced 5-hydroxytryptamine (5-HT) metabolism in the brain and gut. Untargeted metabolomic profiling further identified the bile acid metabolites taurocholate and deoxycholic acid as direct A. muciniphila-derived molecules that are, individually, sufficient to rescue the CRS-induced impaired 5-HT metabolism and depression-like behaviors. Thus, we report metformin reprograms 5-HT metabolism via microbiome-brain interactions to mitigate depressive syndromes, providing novel insights into gut microbiota-derived bile acids as potential therapeutic candidates for depressive mood disorders from bench to bedside.

Exploring and Validating the Mechanism of Ulinastatin in the Treatment of Sepsis-Associated Encephalopathy Based on Transcriptome Sequencing

Purpose

Sepsis can induce sepsis-associated encephalopathy (SAE), with Ulinastatin (UTI) serving a critical anti-inflammatory role. This study aimed to identify the hub genes in an SAE mouse model following UTI intervention and investigate the underlying molecular mechanisms.

Materials and Methods

Through differential expression analysis to obtain differentially expressed genes (DEGs), ie, UTI vs CLP (DEGs1) and Con vs CLP (DEGs2). After taking the intersection of the genes with opposite differential trends in these two parts and immune-related genes (IRGs), DE-IRGs were obtained. Hub genes in the protein-protein interaction (PPI) network were then determined using six algorithms from the Cytohubba plugin in Cytoscape. Gene set enrichment analysis (GSEA) was employed to explore the functional relevance of these hub genes. Additionally, the immune microenvironment across the three groups was compared, and hub gene-related drugs were predicted using an online database. Finally, qRT-PCR was used to validate the expression of the hub genes in hippocampal tissue from CLP mice.

Results

RNA sequencing obtained 864 differentially expressed genes (DEGs) (CLP vs Con) and 279 DEGs (UTI vs CLP). Taking the intersection of DEGs with opposite expression trends yielded 165 DEGs. Six key genes (ICAM - 1, IRF7, IL - 1β, CCL2, IL - 6 and SOCS3) were screened by six algorithms. Immune infiltration analysis found that Treg cells were reversed after treatment with UTI in the diseased state. A total of 106 hub - gene - related drugs were predicted, among which BINDARIT - CCL2 and LIFITEGRAST - ICAM1 showed particularly high affinities. The qRT - PCR verification results were consistent with the sequencing results.

Conclusion

In conclusion, ICAM-1, IRF7, IL-1β, CCL2, IL-6, and SOCS3 were identified as potential therapeutic targets in SAE mice treated with UTI. This study offers theoretical support for UTI as a treatment option for SAE.

Protective Effects of Baicalein on Lipopolysaccharide-Induced AR42J PACs through Attenuation of Both Inflammation and Pyroptosis via Downregulation of miR-224-5p/PARP1

Background

Baicalein has been used to treat inflammation-related diseases; nevertheless, its specific mechanism of action is unclear. Therefore, we examined the protective effects of baicalein on lipopolysaccharide-induced damage to AR42J pancreatic acinar cells (PACs) and determined its mechanism of action for protection.

Methods

An in vitro cell model of acute pancreatitis (AP) was established using lipopolysaccharide (LPS) (1 mg/L)-induced PACs (AR42J), and the relative survival rate was determined using the 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) technique. Flow cytometry was applied to evaluate the apoptotic rates of AR42J PACs. The RNA and protein expression of miR-224-5p, poly ADP-ribose polymerase-1 (PARP1), nuclear transcription factor-κB65 (NF-κB65), phospho-kappa B alpha(p-IκB-α), interleukin(IL)-18R, NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), gasdermin D (GSDMD), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1 was detected based on the WB and RT-PCR assays. IL-1β, IL-6, IL-18, and TNF-α expression levels in AR42J cells were measured via ELISA method. The cell morphology was examined using the AO/EB method.

Results

The experiment confirmed a significant increase in the activity of AR42J cells treated with various doses of baicalein. Moreover, IL-1β, IL-6, TNF-α, and IL-18 expression levels in AR42J cells were dramatically reduced (P  < 0.05), while miR-224-5p level was obviously enhanced. The protein and gene expression of PARP1, NF-κB65, p-IκB-α, IL-18R, GSDMD, ASC, NLRP3, and caspase-1 was obviously decreased (P < 0.05). Apoptosis in AR42J cells was significantly reduced with significant improvement in cell morphology.

Conclusion

Baicalein may significantly alleviate LPS-induced AR42J PAC damage by inhibiting the inflammatory response and pyroptosis. Its mode of action might be linked to higher miR-224-5p expression, which inhibits the PARP1/NF-κB and NLPR3/ASC/caspase-1/GSDMD pathways.

Neuroprotective effects of ulinastatin on Escherichia coli meningitis rats through inhibiting PKCα phosphorylation and reducing zonula occludens-1 degradation

Ulinastatin, a broad-spectrum inflammatory inhibitor widely employed in the management of severe pancreatitis and sepsis, has not been extensively investigated for its therapeutic potential in bacterial meningitis. This study aims to assess the neuroprotective effects of ulinastatin on bacterial meningitis and elucidate its underlying mechanism. The rat model of bacterial meningitis was established by intracerebral injection of Escherichia coli. 3-week-old SD rats were randomly divided into 5 groups with 8 rats in each group, including control group, E.coli group, E.coli + UTI group (ulinastatin 50000IU/kg), E.coli + UTI + PMA group (ulinastatin 50000IU/kg + PMA 200 ug/kg), and E.coli + PMA group(PMA 200 ug/kg). Behavioral changes were assessed by Loeffler neurobehavioral score. Histomorphologic changes and apoptosis were assessed by hematoxylin and eosin staining, Nissl staining and TUNEL staining. Immunohistochemistry and immunofluorescence and western blotting were used to detect the expression levels of zonula occludens-1 (ZO-1) and phosphorylation protein kinase C (PKCα).It was found that ulinastatin treatment in Escherichia coli meningitis rats improved neurological function, alleviated meningeal inflammatory infiltration, reduced neuronal death, promoted the integrity of the blood-brain barrier structure. Moreover, phorbol myristate acetate (PMA, a protein kinase C activator), blocked the effective action of ulinastatin. These findings suggest that ulinastatin had neuroprotective effects on bacterial meningitis by inhibiting PKCα phosphorylation and reducing ZO-1 degradation, demonstrating that ulinastatin may be a promising strategy in the treatment of bacterial meningitis.

Sodium Houttuyniae attenuates ferroptosis by regulating TRAF6-c-Myc signaling pathways in lipopolysaccharide-induced acute lung injury (ALI)

The impact of Sodium Houttuyniae (SH) on lipopolysaccharide (LPS)-induced ALI has been investigated extensively. However, it remains ambiguous whether ferroptosis participates in this process. This study aimed to find out the impacts and probable mechanisms of SH on LPS-induced ferroptosis. A rat ALI model and type II alveolar epithelial (ATII) cell injury model were treated with LPS. Enzyme-linked immunosorbent assay (ELISA), hematoxylin-eosin (HE) staining, and Giemsa staining were executed to ascertain the effects of SH on LPS-induced ALI. Moreover, Transmission electron microscopy, Cell Counting Kit-8 (CCK8), ferrous iron colorimetric assay kit, Immunohistochemistry, Immunofluorescence, Reactive oxygen species assay kit, western blotting (Wb), and qRT-PCR examined the impacts of SH on LPS-induced ferroptosis and ferroptosis-related pathways. Theresults found that by using SH treatment, there was a remarkable attenuation of ALI by suppressing LPS-induced ferroptosis. Ferroptosis was demonstrated by a decline in the levels of glutathione peroxidase 4 (GPX4), FTH1, and glutathione (GSH) and a surge in the accumulation of malondialdehyde (MDA), reactive oxygen species (ROS), NOX1, NCOA4, and Fe2+, and disruption of mitochondrial structure, which were reversed by SH treatment. SH suppressed ferroptosis by regulating TRAF6-c-Myc in ALI rats and rat ATII cells. The results suggested that SH treatment attenuated LPS-induced ALI by repressing ferroptosis, and the mode of action can be linked to regulating the TRAF6-c-Myc signaling pathway in vivo and in vitro.

Protective Effect of a Isothiazolinone Derivative on Acute Lung Injury by Regulating PI3K-AKT Signaling Pathway

Acute lung injury (ALI) is a prevalent organ injury in sepsis, characterized by an inflammatory reactive disorder. Both the incidence and mortality rates of ALI have been steadily increasing. Isothiazolinone derivatives have displayed anti-inflammatory activity and have shown effectiveness in treating pneumonia. The objective of the study is to assess the effects and mechanisms of the isothiazolinone derivative 4-benzoyl-2-butyl-5-(ethylsulfinyl)isothiazol-3(2H)-one (C6) on sepsis-induced ALI.The analysis of biological function and signal pathway enrichment demonstrated that C6 primarily exhibited anti-inflammatory effects. Administration of different doses of C6 through intraperitoneal injection significantly improved the survival rate, body temperature, and body mass of mice with ALI induced by cecal ligation and puncture (CLP). Additionally, it mitigated lung tissue injury, pulmonary edema, lung permeability, inflammatory cell infiltration, apoptosis, and the expression of inflammatory cytokines. Network targeting analysis and experimental validation in mouse leukemia cells of monocyte macrophage (RAW264.7) cells and CLP-induced ALI mice revealed that the anti-inflammatory effect of C6 was mediated by the inhibition of the phosphatidylinositol 3 kinase -protein kinase B (PI3K-AKT) signaling pathway. The research suggest that C6 has protective effects against ALI by inhibiting the PI3K-AKT signaling pathway. This information could be valuable in developing potential treatments for ALI.

A comparative analysis of sivelestat sodium hydrate and ulinastatin combination therapy in the treatment of sepsis with acute respiratory distress syndrome

OBJECTIVE

This comparative analysis aimed to investigate the efficacy of Sivelestat Sodium Hydrate (SSH) combined with Ulinastatin (UTI) in the treatment of sepsis with acute respiratory distress syndrome (ARDS).

METHODS

A control group and an observation group were formed with eighty-four cases of patients with sepsis with ARDS, with 42 cases in each group. The control group was intravenously injected with UTI based on conventional treatment, and the observation group was injected with SSH based on the control group. Both groups were treated continuously for 7 days, and the treatment outcomes and efficacy of both groups were observed. The Murray Lung Injury Score (MLIS), Sequential Organ Failure Assessment (SOFA), and Acute Physiology and Chronic Health Evaluation II (APACHE II) were compared. Changes in respiratory function, inflammatory factors, and oxidative stress indicators were assessed. The occurrence of adverse drug reactions was recorded.

RESULTS

The total effective rate in the observation group (95.24%) was higher than that in the control group (80.95%) (P < 0.05). The mechanical ventilation time, intensive care unit (ICU) hospitalization time, and duration of antimicrobial medication in the observation group were shorter and multiple organ dysfunction syndrome incidence was lower than those in the control group (P < 0.05). The mortality rate of patients in the observation group (35.71%) was lower than that in the control group (52.38%), but there was no statistically significant difference between the two groups (P > 0.05). MLIS, SOFA, and APACHE II scores in the observation group were lower than the control group (P < 0.05). After treatment, respiratory function, inflammation, and oxidative stress were improved in the observation group (P < 0.05). Adverse reactions were not significantly different between the two groups (P > 0.05).

CONCLUSION

The combination of SSH plus UTI improves lung injury and pulmonary ventilation function, and reduces inflammation and oxidative stress in patients with sepsis and ARDS.

P75NTR+CD64+ neutrophils promote sepsis-induced acute lung injury

Patients suffering from sepsis-induced acute lung injury (ALI) exhibit a high mortality rate, and their prognosis is closely associated with infiltration of neutrophils into the lungs. In this study, we found a significant elevation of CD64+ neutrophils, which highly expressed p75 neurotrophin receptor (p75NTR) in peripheral blood of mice and patients with sepsis-induced ALI. p75NTR+CD64+ neutrophils were also abundantly expressed in the lung of ALI mice induced by lipopolysaccharide. Conditional knock-out of the myeloid lineage's p75NTR gene improved the survival rates, attenuated lung tissue inflammation, reduced neutrophil infiltration and enhanced the phagocytic functions of CD64+ neutrophils. In vitro, p75NTR+CD64+ neutrophils exhibited an upregulation and compromised phagocytic activity in blood samples of ALI patients. Blocking p75NTR activity by soluble p75NTR extracellular domain peptide (p75ECD-Fc) boosted CD64+ neutrophils phagocytic activity and reduced inflammatory cytokine production via regulation of the NF-κB activity. The findings strongly indicate that p75NTR+CD64+ neutrophils are a novel pathogenic neutrophil subpopulation promoting sepsis-induced ALI.

Redefining Immune Dynamics in Acute Pancreatitis: The Protective Role of Galectin-3 Deletion and Treg Cell Enhancement

Acute pancreatitis (AP) is a complex inflammatory condition that can lead to systemic inflammatory responses and multiple organ dysfunction. This study investigates the role of Galectin-3 (Gal-3), a β-galactoside-binding lectin, in modulating acquired immune responses in AP. Acute pancreatitis was induced by ligation of the bile-pancreatic duct in wild-type and Galectin-3-deficient C57BL/6 mice. We determined the phenotypic and molecular features of inflammatory cells, serum concentrations of amylase, pancreatic trypsin activity, and pancreatic and lung pathology. Galectin-3 deficiency decreased the total number of CD3+CD49- T cells and CD4+ T helper cells, downregulated the production of inflammatory cytokine and IFN-γ, and increased the accumulation of IL-10-producing Foxp3+ T regulatory cells and regulatory CD4+ T cells in the pancreata of diseased animals. The deletion of Galectin-3 ameliorates acute pancreatitis characterized by lowering serum amylase concentration and pancreatic trypsin activity, and attenuating of the histopathology of the lung. These findings shed light on the role of Galectin-3 in acquired immune response in acute pancreatitis and identify Galectin-3 as an attractive target for investigation of the immunopathogenesis of disease and for consideration as a potential therapeutic target for patients with acute inflammatory disease of the pancreas.

miRNA-206-3p alleviates LPS-induced acute lung injury via inhibiting inflammation and pyroptosis through modulating TLR4/NF-κB/NLRP3 pathway

Acute lung injury (ALI) is life-threatening. MicroRNAs (miRNAs) are often abnormally expressed in inflammatory diseases and are closely associated with ALI. This study investigates whether miRNA-206-3p attenuates pyroptosis in ALI and elucidates the underlying molecular mechanisms. ALI mouse and cell models were established through lipopolysaccharide (LPS) treatment for 24 h. Subsequently, the models were evaluated based on ultrasonography, the lung tissue wet/dry (W/D) ratio, pathological section assessment, electron microscopy, and western blotting. Pyroptosis in RAW264.7 cells was then assessed via electron microscopy, immunofluorescence, and western blotting. Additionally, the regulatory relationship between miRNA-206-3p and the Toll-like receptor (TLR)4/nuclear factor (NF)-κB/Nod-like receptor protein-3 (NLRP3) pathway was verified. Finally, luciferase reporter gene and RNA pull-down assays were used to verify the targeting relationship between miRNA-206-3p and TLR4. miRNA206-3p levels are significantly decreased in the LPS-induced ALI model. Overexpression of miRNA-206-3p improves ALI, manifested as improved lung ultrasound, improved pathological changes of lung tissue, reduced W/D ratio of lung tissue, release of inflammatory factors in lung tissue, and reduced pyroptosis. Furthermore, overexpression of miRNA-206-3p contributed to reversing the ALI-promoting effect of LPS by hindering TLR4, myeloid differentiation primary response 88 (MyD88), NF-κB, and NLRP3 expression. In fact, miRNA-206-3p binds directly to TLR4. In conclusion, miRNA-206-3p alleviates LPS-induced ALI by inhibiting inflammation and pyroptosis via TLR4/NF-κB/NLRP3 pathway modulation.

Inhibition of sepsis-induced pancreatic injury by leukotriene receptor antagonism via modulation of oxidative injury, and downregulation of inflammatory markers in experimental rats

The purpose of this study is to investigate the effect of montelukast on lipopolysaccharide (LPS)-induced pancreatitis. Adult male Wistar rats were divided into 5 groups: normal control, control montelukast, LPS group, and two LPS + montelukast-treated groups. Acute pancreatitis (AP) was induced by a single dose of LPS (6 mg/kg, i.p.), while montelukast was given in two different doses (10 and 20 mg/kg/day) for 3 consecutive days prior to the injection of LPS. AP was demonstrated by significant increases in serum levels of lactate dehydrogenase (LDH) and pancreatic enzymes lipase and amylase. Proinflammatory response activation was evident by elevated serum levels of nitric oxide (NO) and increased pancreatic concentrations of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1β), and intercellular adhesion molecule-1 (ICAM-1). The activity of myeloperoxidase (MPO), a neutrophil infiltration marker, has also been increased. Oxidative stress was confirmed by significant increases in the concentrations of lipid peroxides measured as thiobarbituric acid reactive substances (TBARS) and decreases in the concentrations of reduced glutathione (GSH) in the pancreatic tissues of animals treated with LPS. Histological examination confirmed the biochemical alterations. Montelukast treatment reversed all these biochemical indices and histopathological changes that LPS induced. Montelukast reduced the increase in serum levels of lipase, amylase, LDH, total nitrite/nitrate, TNF-α, IL-1β, and ICAM-1. MPO activities and TBARS concentrations were also suppressed while GSH content was increased in pancreatic tissues. These results show that montelukast may be a beneficial pharmacological agent in protection against LPS-induced oxidative pancreatic injury by inhibiting neutrophil infiltration, counteracting oxidative stress, and suppressing inflammatory mediators.

Protective effects of Dioscin against sepsis-induced cardiomyopathy via regulation of toll-like receptor 4/MyD88/p65 signal pathway

BACKGROUND

Dioscin has many pharmacological effects; however, its role in sepsis-induced cardiomyopathy (SIC) is unknown. Accordingly, we concentrate on elucidating the mechanism of Dioscin in SIC rat model.

METHODS

The SIC rat and H9c2 cell models were established by lipopolysaccharide (LPS) induction. The heart rate (HR), left ventricle ejection fraction (LVEF), mean arterial blood pressure (MAP), and heart weight index (HWI) of rats were evaluated. The myocardial tissue was observed by hematoxylin and eosin staining. 4-Hydroxy-2-nonenal (4-HNE) level in myocardial tissue was detected by immunohistochemistry. Superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activities in serum samples of rats and H9c2 cells were determined by colorimetric assay. Bax, B-cell lymphoma-2 (Bcl-2), toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), phosphorylated-p65 (p-p65), and p65 levels in myocardial tissues of rats and treated H9c2 cells were measured by quantitative real-time PCR and Western blot. Viability and reactive oxygen species (ROS) accumulation of treated H9c2 cells were assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and dihydroethidium staining assays.

RESULTS

Dioscin decreased HR and HWI, increased LVEF and MAP, alleviated the myocardial tissue damage, and reduced 4-HNE level in SIC rats. Dioscin reversed LPS-induced reduction on SOD, CAT, GSH, and Bcl-2 levels, and increment on Bax and TLR4 levels in rats and H9c2 cells. Overexpressed TLR4 attenuated the effects of Dioscin on promoting viability, as well as dwindling TLR4, ROS and MyD88 levels, and p-p65/p65 value in LPS-induced H9c2 cells.

CONCLUSION

Protective effects of Dioscin against LPS-induced SIC are achieved via regulation of TLR4/MyD88/p65 signal pathway.

SHCBP1 Overexpression Aggravates Pancreatitis by Triggering the Loss of Primary Cilia

Primary cilia are microtubule-based organelles that mediate various biological processes. Pancreatic cells are typically ciliated; however, the role of primary cilia in acute pancreatitis (AP) is largely unknown. Here, we report that the loss of primary cilia, mediated by SHCBP1 (SHC1 binding protein), exerted a provocative effect on AP. Primary cilia are extensively lost in inflamed pancreatic cells in vitro and in mouse tissues with AP in vivo. Abrogation of primary cilia aggravated lipopolysaccharide (LPS)-induced inflammation in pancreatic cells. Mechanistically, AP induced the overexpression of SHCBP1 mitotic factor, which is localized to the base of primary cilia. SHCBP1 deficiency relieved LPS- and cerulein-induced pancreatitis by preventing the loss of primary cilia in vitro and in vivo. Collectively, we reveal that inflammation-induced loss of primary cilia aggravates AP. Furthermore, abrogating SHCBP1 to prevent primary cilia loss is an efficient strategy to combat AP.

Regulatory effects of mangiferin on LPS-induced inflammatory responses and intestinal flora imbalance during sepsis

Studies suggest that mangiferin (MAF) has good therapeutic effects on chronic bronchitis and hepatitis. Also, it is one of the antiviral ingredients in Anemarrhena asphodeloides Bunge. However, its effect on the LPS-induced inflammation and intestinal flora during sepsis remains unclear yet. In the present study, LPS-stimulated inflammation RAW264.7 cells and LPS-induced sepsis mice were used to evaluate the efficacy of MAF in vitro and in vivo. 16S rDNA sequencing was performed to analyze the characteristics of intestinal flora of the sepsis mice. It has been demonstrated that MAF (12.5 and 25 μg/mL) significantly inhibited protein expressions of TLR4, MyD88, NF-κB, and TNF-α in the LPS-treated cells and reduced the supernatant TNF-α and IL-6 levels. In vivo, MAF (20 mg/kg) markedly protected the sepsis mice and reduced the serum TNF-α and IL-6 levels. Also, MAF significantly downregulated the protein expressions of TLR4, NF-κB, and MyD88 in the livers. Importantly, MAF significantly attenuated the pathological injuries of the livers and small intestines. Further, MAF significantly increased proportion of Bacteroidota and decreased the proportions of Firmicutes, Desulfobacterota, Actinobacteriota, and Proteobacteria at phylum level, and it markedly reduced the proportions of Escherichia-Shigella, Pseudoalteromonas, Staphylococcus at genus level. Moreover, MAF affects some metabolism-related pathways such as citrate cycle (TCA cycle), lipoic acid metabolism, oxidative phosphorylation, bacterial chemotaxis, fatty acid biosynthesis, and peptidoglycan biosynthesis of the intestinal flora. Thus, it can be concluded that MAF as a treatment reduces the inflammatory responses in vitro and in vivo by inhibiting the TLR4/ MyD88/NF-κB pathway, and corrects intestinal flora imbalance during sepsis to some degree.

Sema3A Alleviates the Malignant Behaviors of Gastric Cancer Cells by Inhibiting NRP-1

AIMS AND OBJECTIVES

Semaphorin3A (Sema3a) is lowly expressed in the peripheral blood of gastric cancer patients, suggesting Sema3a may be involved in the progression of gastric cancer. Nevertheless, the specific role and the potential regulatory mechanism of Sema3a in gastric cancer is still obscure. Neuropilin-1 (NRP-1) has been reported to interact with Sema3a; herein, we intended to reveal the role and regulatory mechanism of Sema3a/neuropilin-1 (NRP-1) in gastric cancer progression.

METHODS

Cell transfection was carried out to regulate gene expression. CCK-8 and colony formation assays were applied to estimate cell proliferation. Scratch assay and transwell assay were conducted to assess the cell migration and invasion abilities. Angiogenesis ability was assessed using a tubule-forming assay. The expression of corresponding genes and proteins were detected by RT-qPCR and western blot, respectively.

RESULTS

Data showed that Sema3a was downregulated in gastric cancer cells and NRP-1 was upregulated. Sema3a overexpression repressed NRP-1 level in AGS cells. Overexpression of Sema3a inhibited cell proliferation, migration, and invasion abilities as well as epithelial-mesenchymal transition (EMT) of AGS cells. Overexpression of Sema3a inhibited tube formation and reduced the expression of VEGFA/VEGFR2 in AGS cells. However, the effects of Sema3a overexpression on the malignant behaviors in AGS cells were partly reversed by NRP-1 overexpression. Additionally, Sema3a overexpression enhanced the inhibitory effects of Ramucirumab, an anti-VEGFR2 agent, on the proliferative, migratory, and invasive capabilities as well as EMT in AGS cells.

CONCLUSION

In conclusion, Sema3a alleviates the proliferation, migration, invasion, and angiogenesis capabilities of gastric cancer cells via repressing NRP-1. This finding may provide potential targets for gastric cancer therapy.

MiR-107-3p Knockdown Alleviates Endothelial Injury in Sepsis via Kallikrein-Related Peptidase 5

INTRODUCTION

Endothelial injury is a major characteristic of sepsis and contributes to sepsis-induced multiple-organ dysfunction. In this study, we investigated the role of miR-107-3p in sepsis-induced endothelial injury.

METHODS

Human umbilical vein endothelial cells (HUVECs) were exposed to 20 μg/mL of lipopolysaccharide (LPS) for 6-48 h. The levels of miR-107-3p and kallikrein-related peptidase 5 (KLK5) were examined. HUVECs were treated with LPS for 12 h and subsequently transfected with miR-107-3p inhibitor, KLK5 siRNA, or cotransfected with KLK5 siRNA and miR-107-3p inhibitor/negative control inhibitor. Cell survival, apoptosis, invasion, cell permeability, inflammatory response, and the Toll-like receptor 4/nuclear factor κB signaling were evaluated. In addition, the relationship between miR-107-3p and KLK5 expression was predicted and verified.

RESULTS

LPS significantly elevated miR-107-3p levels, which peaked at 12 h. Conversely, the KLK5 level was lower in the LPS group than in the control group and was lowest at 12 h. MiR-107-3p knockdown significantly attenuated reductions in cell survival and invasion, apoptosis promotion, hyperpermeability and inflammation induction, and activation of the NF-κB signaling caused by LPS. KLK5 knockdown had the opposite effect. Additionally, KLK5 was demonstrated as a target of miR-107-3p. MiR-107-3p knockdown partially reversed the effects of KLK5 depletion in LPS-activated HUVECs.

CONCLUSIONS

Our findings indicate that miR-107-3p knockdown may protect against sepsis-induced endothelial cell injury by targeting KLK5. This study identified a novel therapeutic target for sepsis-induced endothelial injury.

Clinical Efficacy of Ulinastatin Combined with Azithromycin in the Treatment of Severe Pneumonia in Children and the Effects on Inflammatory Cytokines and Oxidative Stress: A Retrospective Cohort Study

Purpose

This retrospective cohort study aimed to evaluate the clinical efficacy of ulinastatin (UTI) and azithromycin (AZM) combination therapy in treating severe pneumonia in children and its impact on inflammatory cytokines and oxidative stress.

Patients and Methods

This retrospective cohort study was conducted from January 1, 2019, to January 1, 2021, involving pediatric patients diagnosed with severe mycoplasma pneumonia (SMPP). The pediatric patients were divided into two groups: those receiving UTI and AZM combination therapy (treatment group) and those receiving azithromycin alone (control group). We compared the two groups regarding clinical data, disease outcomes, inflammatory cytokines, and oxidative stress levels.

Results

Baseline characteristics did not significantly differ between the two groups. UTI, in combination with AZM, significantly improved blood oxygen levels, inflammatory infection markers, and relevant clinical symptoms in patients with SMPP on the 3rd day of treatment. Additionally, it significantly reduced the levels of inflammatory cytokines TNF-a, IL-6, IL-1β, and IL-10, as well as oxidative stress markers GSH and SOD.

Conclusion

Combining UTI and AZM can rapidly alleviate clinical symptoms and effectively control the progression of patients with SMPP. Therefore, this treatment approach deserves consideration for clinical promotion and utilization.

Ulinastatin inhibits the metastasis of nasopharyngeal carcinoma by involving uPA/uPAR signaling

Distant metastasis is the primary reason for treatment failure in patients with nasopharyngeal carcinoma (NPC). In this study, we investigated the effect of ulinastatin (UTI) on NPC metastasis and its underlying mechanism. Highly-metastatic NPC cell lines S18 and 58F were treated with UTI and the effect on cell proliferation, migration, and invasion were determined by MTS and Transwell assays. S18 cells with luciferase-expressing (S18-1C3) were injected into the left hind footpad of nude mice to establish a model of spontaneous metastasis from the footpad to popliteal lymph node (LN). The luciferase messenger RNA (mRNA) was measured by quantitative polymerase chain reaction (qPCR), and the metastasis inhibition rate was calculated. Key molecular members of the UTI-related uPA, uPAR, and JAT/STAT3 signaling pathways were detected by qPCR and immunoblotting. UTI suppressed the migration and infiltration of S18 and 5-8F cells and suppressed the metastasis of S18 cells in vivo without affecting cell proliferation. uPAR expression decreased from 24 to 48 h after UTI treatment. The antimetastatic effect of UTI is partly due to the suppression of uPA and uPAR. UTI partially suppresses NPC metastasis by downregulating the expression of uPA and uPAR.

miRNA, lncRNA and circRNA: targeted molecules with therapeutic promises in Mycoplasma pneumoniae infection

Mycoplasma pneumoniae (MP) is primarily recognized as a respiratory pathogen that causes community-acquired pneumonia, which can lead to acute upper and lower airway inflammation and extrapulmonary syndrome. Refractory pneumonia caused by MP can cause severe complications and even be life-threatening, particularly in infants and the elderly. It is well-known that non-coding RNAs (ncRNAs) represented by miRNAs, lncRNAs and circRNAs have been manifested to be widely involved in the regulation of gene expression. Growing evidence indicates that these ncRNAs have distinct differentiated expression in MP infection and affect multiple biological processes, playing an indispensable role in the initiation and promotion of MP infection. However, the epigenetic mechanisms involved in the development of MP infection remain unclear. This article reviews the mechanisms by which miRNAs, lncRNAs, and circRNAs mediate MP infection, such as inflammatory responses, apoptosis and pulmonary fibrosis. Focusing on miRNAs, lncRNAs and circRNAs associated with MP infection could provide new insights into this disease's early diagnosis and therapeutic approaches.

Safflor Yellow A Protects Beas-2B Cells Against LPS-Induced Injury via Activating Nrf2

Acute lung injury and its severe form acute respiratory distress syndrome are lethal lung diseases. So far, effective therapy for the diseases is deficient and the prognosis is poor. Recently, it was found activating nuclear factor erythroid 2-related factor 2 could attenuate the injury including inflammation, oxidative stress, and apoptosis in those diseases. To discover novel therapy, we have evaluated safflor yellow A and explored the underlying mechanisms using Beas-2B cells injured by lipopolysaccharide. As a result, safflor yellow A could improve the viability of Beas-2B cells treated with lipopolysaccharide. Further investigations have revealed safflor yellow A suppressed oxidative stress induced by lipopolysaccharide via reducing reactive oxygen species and malondialdehyde, and elevating superoxide dismutase, catalase, and glutathione peroxidase. Meanwhile, the inflammation resulting from lipopolysaccharide was ameliorated through decreasing the pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1β, and interleukin-6. It was also found nuclear factor κB was inactivated by safflor yellow A. In addition, safflor yellow A downregulated cysteinyl aspartate specific proteinase-3 and Bcl-2-associated X protein and upregulated B-cell lymphoma-2 to inhibited apoptosis of Beas-2B cells induced by lipopolysaccharide. The activation of nuclear factor erythroid 2-related factor 2 was observed in Beas-2B cells, which was associated with the protective effects of safflor yellow A. And molecular docking elucidated safflor yellow A interacted with Kelch-like ECH-associated protein 1 to activate nuclear factor erythroid 2-related factor 2. These results can provide evidences for the discovery of novel therapy for further evaluation of safflor yellow A in the treatment of acute lung injury and acute respiratory distress syndrome.

Graphical Abstract

Baicalin alleviates silica-induced lung inflammation and fibrosis by inhibiting TLR4/NF-?B pathway in rats

Silicosis is an occupational lung disease caused by inhaling silica dust. The disease is characterized by early lung inflammation and late irreversible pulmonary fibrosis. Here we report the effect of Baicalin, a main flavonoid compound from the roots of Chinese herbal medicine Huang Qin on silicosis in a rat model. Results showed Baicalin (50 or 100 mg/kg/day) can mitigate the silica-induced lung inflammation and reduce the harm of alveolar structure and the blue region of collagen fibers in rat lung at 28 days after administration. At the same time, Baicalin also diminished the level of interleukin-1beta (IL-1beta, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) in lung tissues. The protein expression of collagen I (Col-1), alpha-smooth muscle actin (alpha-SMA) and vimentin were down-regulated while E-cadherin (E-cad) was increased in Baicalin-treated rats. In addition, the Toll Like Receptor 4 (TLR4)/ nuclear factor kappaB (NF-kappaB) pathway was enabled at 28 days after silica infusion, and the treatment of Baicalin diminished the expression of TLR4 and NF-?B in the lungs of rat with silicosis. These results suggested that Baicalin inhibited the pulmonary inflammatory and fibrosis in a rat model of silicosis, which could be attributed to inhibition of the TLR4/NF-kappaB pathway.

RAGE-TLR4 Crosstalk Is the Key Mechanism by Which High Glucose Enhances the Lipopolysaccharide-Induced Inflammatory Response in Primary Bovine Alveolar Macrophages

The receptor of advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR4) are important receptors for inflammatory responses induced by high glucose (HG) and lipopolysaccharide (LPS) and show crosstalk phenomena in inflammatory responses. However, it is unknown whether RAGE and TLR4 can influence each other's expression through a crosstalk mechanism and whether the RAGE-TLR4 crosstalk related to the molecular mechanism of HG enhances the LPS-induced inflammatory response. In this study, the implications of LPS with multiple concentrations (0, 1, 5, and 10 μg/mL) at various treatment times (0, 3, 6, 12, and 24 h) in primary bovine alveolar macrophages (BAMs) were explored. The results showed that a 5 μg/mL LPS treatment at 12 h had the most significant increment on the pro-inflammatory cytokine interleukin 1β (IL-1β), IL-6, and tumor necrosis factor (TNF)-α levels in BAMs (p < 0.05) and that the levels of TLR4, RAGE, MyD88, and NF-κB p65 mRNA and protein expression were upregulated (p < 0.05). Then, the effect of LPS (5 μg/mL) and HG (25.5 mM) co-treatment in BAMs was explored. The results further showed that HG significantly enhanced the release of IL-1β, IL-6, and TNF-α caused by LPS in the supernatant (p < 0.01) and significantly increased the levels of RAGE, TLR4, MyD88, and NF-κB p65 mRNA and protein expression (p < 0.01). Pretreatment with FPS-ZM1 and TAK-242, the inhibitors of RAGE and TLR4, significantly alleviated the HG + LPS-induced increment of RAGE, TLR4, MyD88, and NF-κB p65 mRNA and protein expression in the presence of HG and LPS (p < 0.01). This study showed that RAGE and TLR4 affect each other's expression through crosstalk during the combined usage of HG and LPS and synergistically activate the MyD88/NF-κB signaling pathway to promote the release of pro-inflammatory cytokines in BAMs.

Effects of piperlonguminine on lung injury in severe acute pancreatitis <em>via</em> the TLR4/NF-κB pathway

Acute pancreatitis is an inflammatory response in the pancreas, involving activation of pancreatic enzymes. Severe acute pancreatitis (SAP) often causes systemic complications that affect distant organs, including the lungs. The aim of this study was to explore the therapeutic potential of piperlonguminine on SAP-induced lung injury in rat models. Acute pancreatitis was induced in rats by repetitive injections with 4% sodium taurocholate. Histological examination and biochemical assays were used to assess the severity of lung injury, including tissue damage, and levels of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4), reactive oxygen species (ROS), and inflammatory cytokines. We found that piperlonguminine significantly ameliorated pulmonary architectural distortion, hemorrhage, interstitial edema, and alveolar thickening in rats with SAP. In addition, NOX2, NOX4, ROS, and inflammatory cytokine levels in pulmonary tissues were notably decreased in piperlonguminine-treated rats. Piperlonguminine also attenuated the expression levels of toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB). Together, our findings demonstrate for the first time that piperlonguminine can ameliorate acute pancreatitis-induced lung injury via inhibitory modulation of inflammatory responses by suppression of the TLR4/NF-κB signaling pathway.

rFGF4 alleviates lipopolysaccharide-induced acute lung injury by inhibiting the TLR4/NF-κB signaling pathway

Acute lung injury (ALI) is a serious and common clinical disease. Despite significant progress in ALI treatment, the morbidity and mortality rates remain high. However, no effective drug has been discovered for ALI. FGF4, a member of the FGF family, plays an important role in the regulation of various physiological and pathological processes. Therefore, in the present study, we aimed to study the protective effects of FGF4 against LPS-induced lung injury in vivo and in vitro. We found that rFGF4 treatment improved the lung W/D weight ratio, the survival rate, immune cell infiltration and protein concentrations in mice with LPS-induced ALI. Histological analysis revealed that rFGF4 significantly attenuated lung tissue injury and cell apoptosis. Furthermore, rFGF4 inhibited the activation of the TLR4/NF-κB signaling pathway and the production of pro-inflammatory mediators in LPS-injured lung tissues, murine alveolar macrophages (MH-S) and murine pulmonary epithelial (MLE-12) cells. The results of cell experiments further verified that rFGF4 inhibited the production of inflammatory mediators in MH-S cells and MLE-12 cells by regulating the TLR4/NF-κB signaling pathway. These results revealed that rFGF4 protected lung tissues and inhibited inflammatory mediators in mice with LPS-induced ALI by inhibiting the TLR4/NF-κB signaling pathway in MH-S and MLE-12 cells.

Crosstalk between Inflammation and Hemorrhage/Coagulation Disorders in Primary Blast Lung Injury

Primary blast lung injury (PBLI), caused by exposure to high-intensity pressure waves from explosions in war, terrorist attacks, industrial production, and life explosions, is associated with pulmonary parenchymal tissue injury and severe ventilation insufficiency. PBLI patients, characterized by diffused intra-alveolar destruction, including hemorrhage and inflammation, might deteriorate into acute respiratory distress syndrome (ARDS) with high mortality. However, due to the absence of guidelines about PBLI, emergency doctors and rescue teams treating PBLI patients rely on experience. The goal of this review is to summarize the mechanisms of PBLI and their cross-linkages, exploring potential diagnostic and therapeutic targets of PBLI. We summarize the pathophysiological performance and pharmacotherapy principles of PBLI. In particular, we emphasize the crosstalk between hemorrhage and inflammation, as well as coagulation, and we propose early control of hemorrhage as the main treatment of PBLI. We also summarize several available therapy methods, including some novel internal hemostatic nanoparticles to prevent the vicious circle of inflammation and coagulation disorders. We hope that this review can provide information about the mechanisms, diagnosis, and treatment of PBLI for all interested investigators.

Oleocanthal alleviated lipopolysaccharide-induced acute lung injury in chickens by inhibiting TLR4/NF-κB pathway activation

This study aimed to investigate the ameliorative effect of oleocanthal (OC) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in chickens and its possible mechanisms. In total, 20 chickens were randomly divided into 4 groups: control (CON) group, LPS group, LPS + OC group, and OC group. LPS + OC and OC groups were intragastrically administered a 5 mg/kg·d OC dose for 7 d. On d 8, the LPS group and LPS + OC group were intratracheally administered 2 mg/kg LPS for 12 h. It was found that OC ameliorated the pathological morphology and significantly suppressed apoptosis after OC treatment in LPS-induced ALI chicken (P < 0.01). Antioxidant capacity was higher in the LPS + OC group compared with the LPS group (P < 0.01). OC downregulated the related genes and proteins expression of toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway in LPS group (P < 0.01). In conclusion, OC supplementation can alleviate LPS-induced ALI in chickens by suppressing apoptosis, enhancing lung antioxidant capacities and inhibiting TLR4/NF-κB pathway activation.

Geniposidic acid protects lipopolysaccharide-induced acute lung injury via the TLR4/MyD88 signaling pathway in vitro and in vivo

BACKGROUND

Acute lung injury (ALI) is a common respiratory disease and is a serious threat to human health due to the lack of effective treatment. Geniposidic acid (GPA) is an iridoid glucoside extracted from Gardeniae jasminoides Ellis and can treat inflammation-related diseases. This study aimed to investigate the regulatory functions of GPA on lipopolysaccharide (LPS)-induced ALI and its potential mechanism, providing effective strategies for the clinical treatment of ALI.

METHODS

ALI models were constructed by LPS in Sprague-Dawley rats and pulmonary epithelial cells. The function of GPA was investigated by hematoxylin-eosin staining, lung function assessment, Western blot, Masson staining, and Sirius Red staining, quantitative real-time PCR, enzyme-linked immunosorbent assay, cell counting kit-8 assay, apoptosis analysis, and immunofluorescence assays.

RESULTS

Functionally, GPA increased survival, relieved pulmonary epithelial function in response to LPS, repressed pulmonary fibrosis and inflammation caused by ALI in vivo; GPA also repressed pulmonary epithelial cell injury and inflammation induced by LPS in vitro. Mechanistically, GPA decreased the protein levels of TLR4 and MyD88 and accelerated the nuclear export of p65, suggesting that GPA repressed the activation of p65.

CONCLUSION

GPA protected LPS-induced ALI through the TLR4/MyD88 signaling pathway.

[The role and mechanism of autophagy in lipopolysaccharide-induced inflammatory response of A549 cells]

OBJECTIVES

To study the role and mechanism of autophagy in lipopolysaccharide (LPS)-induced inflammatory response of human alveolar epithelial A549 cells.

METHODS

A549 cells were stimulated with LPS to establish a cell model of inflammatory response, and were then grouped (n=3 each) by concentration (0, 1, 5, and 10 μg/mL) and time (0, 4, 8, 12, and 24 hours). The A549 cells were treated with autophagy inhibitor 3-methyladenine (3-MA) to be divided into four groups (n=3 each): control, LPS, 3-MA, and 3-MA+LPS. The A549 cells were treated with autophagy agonist rapamycin (RAPA) to be divided into four groups (n=3 each): control, LPS, RAPA, and RAPA+LPS. The A549 cells were transfected with the Toll-like receptor 4 (TLR4) overexpression plasmid to be divided into four groups (n=3 each): TLR4 overexpression control, TLR4 overexpression, TLR4 overexpression control+LPS, and TLR4 overexpression+LPS. The A549 cells were transfected with TLR4 siRNA to be divided into four groups (n=3 each): TLR4 silencing control,TLR4 silencing, TLR4 silencing control+LPS, and TLR4 silencing+LPS. CCK-8 assay was used to measure cell viability. Western blot was used to measure the protein expression levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4.

RESULTS

After stimulation with 1 μg/mL LPS for 12 hours, the levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4 increased and reached the peak (P<0.05). Compared with the LPS group, the 3-MA+LPS group had reduced expression of autophagy-related proteins and increased expression of inflammation-related proteins and TLR4, while the RAPA+LPS group had increased expression of autophagy-related proteins and reduced inflammation-related proteins and TLR4 (P<0.05). The TLR4 overexpression+LPS group had reduced autophagy-related proteins and increased inflammation-related proteins compared with the TLR4 overexpression control+LPS group, and the TLR4 silencing+LPS group had increased autophagy-related proteins and reduced inflammation-related proteins compared with the TLR4 silencing control+LPS group (P<0.05).

CONCLUSIONS

In the LPS-induced inflammatory response of human alveolar epithelial A549 cells, autophagic flux has a certain protective effect on A549 cells. TLR4-mediated autophagic flux negatively regulates the LPS-induced inflammatory response of A549 cells.

ASIC1a induces mitochondrial apoptotic responses in acute lung injury

AIM

This study aimed to investigate the promoting effect of acid-sensing ion channel 1a (ASIC1a) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and its mechanisms.

METHODS

In this experiment, the ALI rat model was induced by intratracheal injection of LPS, and the ASIC1a specific blocker psalmotoxin-1 (PcTx-1) was injected into the tail vein before LPS administration once. Western blot, immunofluorescence, immunohistochemistry and real-time PCR methods were used to detect ASIC1a and apoptosis-related proteins expressions in lung tissue and RLE-6TN rat type II alveolar epithelial cells. Confocal Laser Scanning Microscopy was used to detect Ca²⁺ fluorescence intensity in RLE-6TN cells.

RESULTS

PcTx-1 pretreatment not only inhibited the pathological changes of LPS-induced ALI in lung tissue, but also inhibited lung dysfunction. PcTx-1 also reduced the increased levels of the apoptosis-related proteins B-cell lymphoma-2-associated X (Bax) and cleaved cysteinyl aspartate specific proteinase 3 (Cleaved caspase-3) and increased the decreased level of B-cell lymphoma-2 (Bcl-2) in the lung tissue of the model group. LPS-induced changes in mitochondrial membrane potential and calcium influx in alveolar epithelial cells were also reversed by PcTx-1.

CONCLUSION

ASIC1a induces an apoptotic response in ALI through mitochondrial apoptosis.

Toll-like Receptor Mediation in SARS-CoV-2: A Therapeutic Approach

The innate immune system facilitates defense mechanisms against pathogen invasion and cell damage. Toll-like receptors (TLRs) assist in the activation of the innate immune system by binding to pathogenic ligands. This leads to the generation of intracellular signaling cascades including the biosynthesis of molecular mediators. TLRs on cell membranes are adept at recognizing viral components. Viruses can modulate the innate immune response with the help of proteins and RNAs that downregulate or upregulate the expression of various TLRs. In the case of COVID-19, molecular modulators such as type 1 interferons interfere with signaling pathways in the host cells, leading to an inflammatory response. Coronaviruses are responsible for an enhanced immune signature of inflammatory chemokines and cytokines. TLRs have been employed as therapeutic agents in viral infections as numerous antiviral Food and Drug Administration-approved drugs are TLR agonists. This review highlights the therapeutic approaches associated with SARS-CoV-2 and the TLRs involved in COVID-19 infection.

Glycyrrhizic Acid Protects Experimental Sepsis Rats against Acute Lung Injury and Inflammation

Background

The incidence of acute lung injury/acute respiratory distress (ALI/ARDS) is high in sepsis aggravating morbidity and mortality. Glycyrrhizic acid (GA) has pharmacological activities in the treatment of inflammation and antiviral.

Materials and Methods

Sepsis rats were constructed by the cecal ligation and puncture (CLP) surgery. After GA (25 and 50 mg/kg) injection, the survival rate, blood oxygen, biochemical indexes, myeloperoxidase (MPO) activity, and wet/dry weight ratio of the lung were observed. The bronchoalveolar lavage fluid was collected to count the cells and measure the level of TNF-α, IL-1β, IL-10, and high mobility group box-1 protein (HMGB1). Lung tissue sections were taken to observe the levels of histopathological injury and apoptosis by HE and TUNEL staining. The levels of HMGB1, TLR4, p-38 MAPK, NF-κB, and ERK1/2 proteins were observed by immunohistochemistry and Western blot.

Results

GA treatment improved the survival rate, blood oxygen, ALT, AST, BUN, and Scr of CLP rats. It could advance the MPO activity, the wet/dry weight ratio, histopathological injury, apoptosis, and the IL-10 level in the lung. After GA injection, the number of total cells, neutrophils, and macrophages in the CLP rats was reduced and the levels of TNF-α, IL-1β, HMGB1, TLR4, p-38 MAPK, and ERK1/2 in the CLP rat were also repressed.

Conclusions

GA treatment may improve the sepsis-induced ALI/ARDS and inflammation by inhibiting HMBG1. This study provided an experimental basis for the prevention and treatment of ALI/ARDS caused by sepsis.

Anti-inflammatory effects of a SERP 30 polysaccharide from the residue of Sarcandra glabra against lipopolysaccharide-induced acute respiratory distress syndrome in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Sarcandra glabra (Thunb.) Nakai, a valuable dietetic Chinese herb, is still widely used today. Multiple ingredients of S. glabra with a variety of activities such as anti-inflammatory, antiviral, and antitumor were studied. However, the Sarcandra glabra (Thunb.) Nakai polysaccharide hasn't been reported for its anti-inflammatory effect.

AIM OF THE STUDY

In this study, the anti-inflammatory activity of Sarcandra glabra (Thunb.) Nakai polysaccharide was assessed in LPS-induced ARDS mice.

MATERIALS AND METHODS

A polysaccharide coded as SERP 30 was obtained by water extraction, alcohol precipitation, and gel filtration. After the physicochemical properties determination and structural characterization, LPS induced-mice ARDS model was used to evaluate the anti-inflammatory and associated antioxidant activities of SERP 30. H&E staining was used to observe the seriousness of lung injury in mice. The ELISA method was used to measure the expression of inflammatory factors (TNF-α and IL-6) in the serum of the mice. The TBA method and the WST-1 method were used to evaluate the oxidative stress injury. Immunohistochemistry was used to distinguish the expression of metalloproteinase-9 (MMP-9), heparinase (HPA), syndecan-1, and decorin in ARDS-mice lung tissue. Western blotting was used to confirm the expression of related proteins in mouse lung tissue.

RESULTS

SERP 30 had a potential role in improving lung damage, reducing inflammation, and preventing oxidative stress. Moreover, SERP 30 significantly attenuated the damage to the endothelial glycocalyx and maintained the integrity of the glycocalyx. The western blotting result implied that the main anti-inflammatory mechanism is directed towards NF-κB and MAPK signaling pathways with inhibiting the activation of associated proteins.

CONCLUSION

This research provides a theoretical basis for treating ARDS by using a byproduct from food resource.

Effects of Corilagin on Lipopolysaccharide-Induced Acute Lung Injury via Regulation of NADPH Oxidase 2 and ERK/NF-κB Signaling Pathways in a Mouse Model

Acute lung injury (ALI) and acute respiratory distress syndrome are clinically life-threatening diseases. Corilagin, a major polyphenolic compound obtained from the herb Phyllanthus urinaria, has anti-inflammatory and antioxidant properties, and in this study, we sought to evaluate the protective effects and mechanisms of corilagin on lipopolysaccharide (LPS)-induced ALI in mice. ALI was induced in the mice by the intratracheal administration of LPS, and following 30 min of LPS challenge, corilagin (5 and 10 mg/kg body weight) was administered intraperitoneally. At 6 h post-LPS administration, lung tissues were collected for analysis. Corilagin treatment significantly attenuated inflammatory cell infiltration, the production of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β, and oxidative stress in lung tissues. In addition, corilagin inhibited the LPS-induced expression of NOX2, ERK, and NF-κB. Corilagin has anti-oxidative and anti-inflammatory effects, and can effectively reduce ALI via attenuation of the NOX2 and ERK/NF-κB signaling pathways.

Ulinastatin promotes macrophage efferocytosis and ameliorates lung inflammation via the ERK5/Mer signaling pathway

Acute lung injury (ALI) is a pneumonic response characterized by neutrophil infiltration. Macrophage efferocytosis is the process whereby macrophages remove apoptotic cells, and is required for ALI inflammation to subside. The glycoprotein ulinastatin (UTI) has an anti‐inflammatory effect during the acute stages of ALI, but its effect on efferocytosis and the subinflammatory stage of ALI is unclear. Extracellular signal‐regulated kinase 5 (ERK5) is a key protein in efferocytosis, and we thus hypothesized that it may be activated by UTI to regulate efferocytosis and the resolution of pneumonia. To test this hypothesis, here we monitored phagocytosis of macrophages through in vivo and in vitro experiments. Pulmonary edema, neutrophil infiltration, protein exudation, and inflammatory factor regression were observed on days 1, 3, 5, and 7 in vivo. RAW264.7 cells were pretreated with different concentrations of UTI and ERK5 inhibitors, and the expression of tyrosine‐protein kinase Mer (Mer) protein on macrophage membrane was detected. UTI increased the phagocytosis of apoptotic neutrophils by macrophages in vitro and in vivo, and promoted the resolution of pneumonia. The protein expression of ERK5 and Mer increased with UTI concentration, while the expression of Mer was down‐regulated by ERK5 inhibitors. Therefore, our results suggest that UTI enhances efferocytosis and reduces lung inflammation and injury through the ERK5/Mer signaling pathway, which may be one of the targets of UTI in the treatment of lung injury.

The Immune Change of the Lung and Bowel in an Ulcerative Colitis Rat Model and the Protective Effect of Sodium Houttuyfonate Combined With Matrine

Objective

To explore the immune change of lung injury of Ulcerative colitis (UC) by observing the changes of inherent immunity and adaptive immunity of the lung and bowel in UC rat models after the treatment of Sodium Houttuyfonate combined with Matrine.

Method

UC rat models were established with the mucous membrane of colon allergize combined with TNBS-alcohol enteroclysis for 1 week and 5 weeks. 1-week experimental rats were divided into normal group and model group, 5/each group. 5-weeks experimental rats were divided into normal group, model group, Sodium Houttuyfonate (2.9mg/ml) combined with Matrine (1.47mg/ml), and positive control sulfasalazine (10mg/ml), 5/each group. All rats were administered by gavage for 5 weeks. The histopathological and fibrotic changes in the lung and bowel were observed, and the expressions of Tumor Necrosis Factor (TNF)- α, interleukin (IL)-8 in the lung, bowel, and serum were detected by radio-immunity and immunohistochemistry, and the mRNA expressions of Toll-like receptor (TLR)-4, nuclear factor kappa (NF-κB), Macrophage migration inhibitory factor (MIF), Mucosal addressing cell adhesion molecule-1 (MadCAM1) and Pulmonary surfactant protein-A (SP-A) in the lung and bowel were detected by Real time-PCR.

Result

Compared with the normal group, the model rats had significant histopathological and fibrotic changes both in the lung and bowel, and all treatment groups were improved. After treatment, TLR4, IL-8, MIF, and TNF-α in the lung decreased (P<0.05); NF-KB, IL-8, and MIF in the bowel increased (P<0.05); MadCAM1 both in lung and bowel decreased (P<0.05); SP-A decreased in bowel and increased in the lung (P<0.05).

Conclusion

The cause of lung injury in this model was found to be related to inherent immunity and adaptive immunity, while the cause of bowel injury in this model was found to be mainly related to adaptive immunity. Sodium Houttuyfonate combined with Matrine could improve bowel and lung injury.

Palmatine alleviates LPS-induced acute lung injury via interfering the interaction of TAK1 and TAB1

Acute lung injury (ALI) is a severe clinical disease marked by uncontrolled inflammation response which lacks effective medicines. Accumulative evidence has indicated that macrophages are therapeutic targets for treating ALI because of its critical role in the inflammatory response.Palmatine (PAL), an isoquinoline alkaloid extracted from natural plants, exhibits effective anti-inflammatory, anti-tumor, and anti-oxidation activities. Here we reported that PAL alleviated LPS-induced acute lung injury and attenuated inflammatory cell infiltration especially neutrophils. Moreover, PAL also attenuated the production of TNF-α, CXCL-1, CXCL-2 and nitric oxide in bronchoalveolar lavage fluid. In addition, PAL remarkably reduced LPS-induced expression of TNF-α, CXCL-1 and CXCL-2 in bone marrow derived macrophages (BMDMs) and alveolar macrophages (AMs). Treatment with PAL inhibited the phosphorylation and interaction of TAK1/TAB1, which in turn attenuated the p38 MAPK and NF-κB signal pathways in BMDMs. Our results indicated that PAL ameliorated LPS-induced ALI by inhibiting macrophage activation through inhibiting NF-κB and p38 MAPK pathways, suggesting that PAL has anti-inflammation effect on ALI.

Gut Microbiota-Derived Diaminopimelic Acid Promotes the NOD1/RIP2 Signaling Pathway and Plays a Key Role in the Progression of Severe Acute Pancreatitis

Impaired intestinal barrier function and gut microbiota dysbiosis are believed to be related to exacerbation of acute pancreatitis (AP). As a bacterial cell wall peptidoglycan component, diaminopimelic acid (DAP) is a specific ligand of NOD1 that regulates the NOD1/RIP2/NF-kB signaling pathway. Here, we investigated the role of DAP in the crosstalk between the gut microbiota and pancreas during the occurrence of AP. Upregulation of NOD1/RIP2/NF-kB and elevated serum DAP levels were found in severe AP (SAP) model rats. The accumulation of DAP in SAP patients corroborated its ability to serve as an indicator of disease severity. Subsequently, SAP rats were treated with oral administration of the traditional Chinese medicine Qingyi Keli (QYKL) as well as neomycin, which can widely eliminate DAP-containing bacteria. Both QYKL and neomycin intervention ameliorated intestinal and pancreatic damage and systemic inflammation in SAP rats. Through 16S rDNA sequencing, we found that QYKL could rehabilitate the gut microbiota structure and selectively inhibit the overgrowth of enteric bacteria, such as Helicobacter and Lactobacillus, in SAP rats without affecting some protective strains, including Romboutsia and Allobaculum. Interestingly, we demonstrated that the decrease in serum DAP was accompanied by suppression of the NOD1/RIP2/NF-kB signaling pathway in both the intestine and pancreas of the two intervention groups. Taken together, these results suggested that the gut microbiota-DAP-NOD1/RIP2 signaling pathway might play a critical role in the progression of AP and that SAP could be alleviated via intervention in the signaling pathway. Our work provides new potential early warning indicators of SAP and targets for intervention.

Anti-Inflammatory Effect of Ulinastatin on the Association Between Inflammatory Phenotypes in Acute Type A Aortic Dissection

Background

Acute type A aortic dissection (ATAAD) is a heterogeneous systemic inflammatory response syndrome. Identification of distinct inflammatory phenotypes may allow more precise therapy and improved care. We aim to investigate whether distinct inflammatory subphenotypes exist in ATAAD patients and respond differently to pharmacotherapies.

Methods

Retrospective analysis of data sets was conducted from the Additive Anti-inflammatory Actions for Aortopathy & Arteriopathy (5A) III study. Inflammatory subphenotypes were derived among 2008 ATAAD patients who received surgical repair at 11 Chinese hospitals (2016–2020) using latent class analysis applied to 14 laboratory signatures within 6 hours of hospital admission. Outcomes included operative mortality (Society of Thoracic Surgeons definition), derived subphenotype frequency, and the potential consequences of phenotype frequency distributions on the treatment effects.

Results

The median (interquartile range) age of patients was 54 (45–62) years, and 1423 (70.9%) were male. A two-class (two subphenotype) model was an improvement over a one-class model (P<·001), with 1451 (72.3%) patients in the hypoinflammatory subphenotype group and 557 (27.7%) in the hyperinflammatory subphenotype group. Patients with the hyperinflammatory subphenotype had higher operative mortality (71 [12.7%] vs 127 [8.8%]; P=0·007) than did those with the hypoinflammatory subphenotype. Furthermore, the interaction between ulinastatin treatment and subphenotype is not significant for operative mortality (P=0.15) but for ventilator time (P=0·04).

Conclusion

Two subphenotypes of ATAAD were identified in the 5A cohort that correlated with clinical outcomes, with significant interaction effect between anti-inflammatory treatment and subphenotypes for ventilator time, suggesting these phenotypes may help in understanding heterogeneity of treatment effects.

Trial Registration

Clinical Trials. Gov: number NCT04918108.

Beneficial effects of aloperine on inflammation and oxidative stress by suppressing necroptosis in lipopolysaccharide-induced acute lung injury mouse model

RATIONALE

Alveolar epithelial cell death, inflammation, and oxidative stress are typical features of acute lung injury (ALI). Aloperine (Alo), an alkaloid isolated from Sophora alopecuroides, has been reported to display various biological effects, such as anti-inflammatory, immunoregulatory, and anti-oxidant properties. In this study, we investigated the effects and mechanisms of Alo in treating a lipopolysaccharide (LPS)-induced ALI in a murine model.

METHODS

The effects of Alo in LPS-induced ALI were investigated in C57BL/6 mice. The RIPK1 inhibitor (Nec-1) and the RIPK3 inhibitor (GSK'872) were used to evaluate the relationship of necroptosis, NF-κB activation, and PDC subunits in LPS-treated mouse alveolar epithelial cells (MLE-12). Then the effects of Alo on necroptosis, inflammation, and oxidative stress of LPS-stimulated MLE-12 cells were evaluated.

RESULTS

Alo significantly attenuated histopathological lung injuries and reduced lung wet/dry ratio in LPS-induced ALI mice. Alo also remarkedly reduced total protein and neutrophils recruitment in bronchoalveolar lavage fluid of ALI mice. Meanwhile, Alo ameliorated the LPS-induced necroptosis in the lungs of ALI mice. The RIPK3 inhibitor GSK'872, but not the RIPK1 inhibitor Nec-1, reversed LPS-induced p65 phosphorylation and translocation to the nucleus in MLE-12 cells. GSK'872 also reversed the LPS-induced increase in ROS and binding of RIPK3 and PDC subunits in MLE-12 cells. Moreover, Alo down-regulated the levels of p-RIPK1, p-RIPK3, p-MLKL, p-p65, the translocation of p65 to the nucleus, and reduced the expression of IL-6 and IL-8 in LPS-stimulated MLE-12 cells. Alo also inhibited the binding of RIPK3 and PDC-E1α, PDC-E1β, PDC-E2, and PDC-E3 and the ROS production in LPS-treated MLE-12 cells.

CONCLUSION

The present study validated the beneficial effects of Alo on LPS-induced ALI , suggesting Alo may be a new drug candidate against ALI.

Protection of Toll-Like Receptor 9 Against Lipopolysaccharide-Induced Inflammation and Oxidative Stress of Pulmonary Epithelial Cells via MyD88-Mediated Pathways

Acute lung injury (ALI) caused by lipopolysaccharide (LPS) is a common, severe clinical syndrome. Injury caused by inflammation and oxidative stress in vascular endothelial and alveolar epithelial cells is a vital process in the pathogenesis of ALI. Toll-like receptor 9 (TLR9) is highly expressed in LPS-induced ALI rats. In this study, Beas-2B human pulmonary epithelial cells and A549 alveolar epithelial cells were stimulated by LPS, resulting in the upregulation of TLR9 in a concentration-dependent manner. Furthermore, TLR9 overexpression and interference vectors were transfected before LPS administration to explore the role of TLR9 in LPS-induced ALI in vitro. The findings revealed that inhibition of TLR9 reduced inflammation and oxidative stress while suppressing apoptosis of LPS-induced Beas-2B and A549 cells, whereas TLR9 overexpression aggravated these conditions. Moreover, TLR9 inhibition resulted in downregulated protein expression of myeloid differentiation protein 88 (MyD88) and activator activator protein 1 (AP-1), as well as phosphorylation of nuclear factor-B (NF-B), c-Jun N terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK). The phosphorylation of extracellular-regulated protein kinases 1/2 was upregulated compared to that of cells subjected to only LPS administration, and this was reversed by TLR9 overexpression. These results indicate that inhibition of TLR9 plays a protective role against LPS-induced inflammation and oxidative stress in Beas-2B and A549 cells, possibly via the MyD88/NF-B and MyD88/MAPKs/AP-1 pathways.

Crosstalk of pyroptosis, ferroptosis, and mitochondrial aldehyde dehydrogenase 2-related mechanisms in sepsis-induced lung injury in a mouse model

Acute lung injury (ALI) is a common complication of sepsis. Mitochondrial aldehyde dehydrogenase 2 (ALDH2), an enzyme involved in aldehyde metabolism, exerts a protective effect against sepsis. This study investigated the possible mechanisms underlying the roles of ALDH2, pyroptosis, and ferroptosis in sepsis-induced lung injury. A mouse model of sepsis-induced lung injury was established by cecal ligation and puncture (CLP); lung morphology was evaluated by calculation of lung coefficient, hematoxylin–eosin staining, and electron microscopy. Malondialdehyde (MDA), reactive oxygen species (ROS), and 4-hydroxy-2-nonenal (4-HNE) protein expression levels were used to detect the level of lipid oxidative stress. In addition, total iron was detected using an iron detection kit, and the expression of ferroptosis-related proteins (PTGS2, GPX4), pyroptosis-related proteins, and ALDH2 was examined using western blotting. To further examine the likely mechanisms, the ferroptosis inhibitor ferrostatin 1 (Fer-1), NLRP3 inflammasome inhibitor MCC950, and ALDH2 activator Alda-1 were added. CLP-treated mice exhibited destruction of lung tissue morphology, lipid peroxidation injury, iron content, and increased lung PTGS2 protein expression, accompanied by a decrease in GPX4 protein expression. CLP also downregulated ALDH2 expression and increased the expression of the NLRP3 inflammasome and pyroptosis-related proteins. These adverse effects of CLP were relieved by Alda-1, Fer-1, and MCC950 treatment. In conclusion, both pyroptosis and ferroptosis participate in CLP-induced ALI, and ALDH2 plays a protective role by reducing pyroptosis and ferroptosis. This study provides a scientific basis for the treatment of lung injury in sepsis.

Exploration of the Mechanism of Lianhua Qingwen in Treating Influenza Virus Pneumonia and New Coronavirus Pneumonia with the Concept of "Different Diseases with the Same Treatment" Based on Network Pharmacology

The 31 main components of Lianhua Qingwen (LHQW) were obtained through a literature and database search; the components included glycyrrhizic acid, emodin, chlorogenic acid, isophoroside A, forsythia, menthol, luteolin, quercetin, and rutin. Sixty-eight common targets for the treatment of novel coronavirus pneumonia (NCP) and influenza virus pneumonia (IVP) were also obtained. A "component-target-disease" network was constructed with Cytoscape 3.2.1 software, and 20 key targets, such as cyclooxygenase2 (COX2), interleukin-6 (IL-6), mitogen-activated protein kinase14 (Mapk14), and tumor necrosis factor (TNF), were screened from the network. The David database was used to perform a Kyoto Encyclopedia of Genes and Genomes (KEGG) signal pathway enrichment analysis and gene ontology (GO) biological process enrichment. Results showed that the key targets of LHQW in the treatment of NCP and IVP mainly involved biological processes, such as immune system process intervention, cell proliferation, apoptosis and invasion, toxic metabolism, cytokine activity, and regulation of the synthesis process. KEGG enrichment analysis revealed that 115 signalling pathways were related to the treatment of LHQW. Amongst them, IL-17, T cell receptor, Th17 cell differentiation, TNF, toll-like receptor, MAPK, apoptosis, and seven other signalling pathways were closely related to the occurrence and development of NCP and IVP. Molecular docking showed that each component had different degrees of binding with six targets, namely, 3C-like protease (3CL), angiotensin-converting enzyme 2 (ACE2), COX2, hemagglutinin (HA), IL-6, and neuraminidase (NA). Rutin, isoforsythiaside A, hesperidin and isochlorogenic acid B were the best components for docking with the six core targets. The first five components with the best docking results were isoforsythiaside, hesperidin, isochlorogenic acid B, forsythin E, and quercetin. In conclusion, LHQW has many components, targets, and pathways. The findings of this work can provide an important theoretical basis for determining the mechanism of LHQW in treating NCP and IVP.

Effect of Ulinastatin on Syndecan-2-Mediated Vascular Damage in IDH2-Deficient Endothelial Cells

Syndecan-2 (SDC2), a cell-surface heparin sulfate proteoglycan of the glycocalyx, is mainly expressed in endothelial cells. Although oxidative stress and inflammatory mediators have been shown to mediate dysfunction of the glycocalyx, little is known about their role in vascular endothelial cells. In this study, we aimed to identify the mechanism that regulates SDC2 expression in isocitrate dehydrogenase 2 (IDH2)-deficient endothelial cells, and to investigate the effect of ulinastatin (UTI) on this mechanism. We showed that knockdown of IDH2 induced SDC2 expression in human umbilical vein endothelial cells (HUVECs). Matrix metalloproteinase 7 (MMP7) influences SDC2 expression. When IDH2 was downregulated, MMP7 expression was increased, as was TGF-β signaling, which regulates MMP7. Inhibition of MMP7 activity using MMP inhibitor II significantly reduced SDC2, suggesting that IDH2 mediated SDC2 expression via MMP7. Moreover, expression of SDC2 and MMP7, as well as TGF-β signaling, increased in response to IDH2 deficiency, and treatment with UTI reversed this increase. Similarly, the increase in SDC2, MMP7, and TGF-β signaling in the aorta of IDH2 knockout mice was reversed by UTI treatment. These findings suggest that IDH2 deficiency induces SDC2 expression via TGF-β and MMP7 signaling in endothelial cells.