Neutrophil Elastase Inhibitor Research Articles

The beneficial effects of neutrophil elastase inhibitor on gastrointestinal dysfunction in sepsis.

To investigate the effects of neutrophil elastase inhibitor (sivelestat sodium) on gastrointestinal function in sepsis. A reanalysis of the data from previous clinical trials conducted at our center was performed. Septic patients were divided into either the sivelestat group or the non-sivelestat group. The gastrointestinal dysfunction score (GIDS), feeding intolerance (FI) incidence, serum levels of intestinal barrier function and inflammatory biomarkers were recorded. The clinical severity and outcome variables were also documented. A total of 163 septic patients were included. The proportion of patients with GIDS ≥2 in the sivelestat group was reduced relative to that in the non-sivelestat group (9.6% vs. 22.5%, p = 0.047) on the 7th day of intensive care unit (ICU) admission. The FI incidence was also remarkably reduced in the sivelestat group in contrast to that in the non-sivelestat group (21.2% vs. 37.8%, p = 0.034). Furthermore, the sivelestat group had fewer days of FI [4 (3, 4) vs. 5 (4-6), p = 0.008]. The serum levels of d-lactate (p = 0.033), intestinal fatty acid-binding protein (p = 0.005), interleukin-6 (p = 0.001), white blood cells (p = 0.007), C-reactive protein (p = 0.001), and procalcitonin (p < 0.001) of the sivelestat group were lower than those of the non-sivelestat group. The sivelestat group also demonstrated longer ICU-free days [18 (0-22) vs. 13 (0-17), p = 0.004] and ventilator-free days [22 (1-24) vs. 16 (1-19), p = 0.002] compared with the non-sivelestat group. In conclusion, sivelestat sodium administration appears to improve gastrointestinal dysfunction, mitigate dysregulated inflammation, and reduce disease severity in septic patients.

Transplantace jater pro deficit alfa-1-antitrypsinu

Summary: Alpha-1-antitrypsin deficiency (AATD) is an autosomal codominant genetic condition which manifests with lung emphysema at young age and with liver disease. A point mutation in the SERPINA1 gene, which encodes 1-antitrypsin (AAT), causes a defective secondary structure of the protein, which subsequently accumulates in the endoplasmic reticulum of hepatocytes and is not transported into the blood and body fluids. Deficiency of AAT, which inhibits neutrophil elastase in the lung, thus allows proteolytic damage to the connective tissue of the lung, leading to the development of emphysema. Liver disease is caused by the accumulation of the mutant AAT in liver cells, contributing to proteotoxic liver injury that can lead to liver cirrhosis. Liver transplantation (LT) is the only curative method; after LT, the recipient has the phenotype of the donor organ and normal serum AAT concentrations. The indication for LT should be considered in all patients with AATD and end-stage liver disease. The patients should be referred to the transplant centre when severe complications of liver cirrhosis, such as variceal bleeding, ascites, encephalopathy, and hepatorenal syndrome. In patients with hepatocellular carcinoma, LT represents an optimal treatment modality in the case of an early, unresectable tumour. The timing of LT is crucial; LT should be performed before the patient develops life-threatening complications of end-stage liver disease. LT should be considered in patients of Child-Pugh classification B and C and MELD score of 15 points or higher. Survival of patients after LT for AADT is excellent. Key words: 1-antitrypsin – 1-antitrypsin deficiency – liver cirrhosis – end-stage liver disease – hepatocellular carcinoma – live transplantation

Unveiling the metabolites underlying the skin anti-ageing properties of Cytinus hypocistis (L.) L. through a biochemometric approach

The genus Cytinus, recognised as one of the most enigmatic in the plant kingdom, has garnered attention for its bioactive potential, particularly its skin anti-ageing properties. Despite this recognition, much remains to be accomplished regarding deciphering and isolating its most active compounds. This study aimed to identify the compounds responsible for C. hypocistis skin anti-ageing potential. Using multivariate analysis, a biochemometric approach was applied to identify the discriminant metabolites by integrating extracts' chemical profile (Liquid Chromatography-High-Resolution Mass Spectrometry, LCHRMS) and bioactive properties. The identified bioactive metabolite was structurally elucidated by 1D and 2D Nuclear Magnetic Resonance (NMR). Among the studied bioactivities, the anti-elastase results exhibited a significant variation among the samples from different years. After the biochemometric analysis, the compound 2,3:4,6-bis(hexahydroxydiphenoyl)glucose, with a molecular mass of 784.075 Da, was structurally elucidated as the discriminant feature responsible for the outstanding human neutrophil elastase inhibition. Remarkably, the subfraction containing this compound exhibited a tenfold improvement in neutrophil elastase inhibition efficacy compared to the crude extract; its effectiveness fell within the same range as SPCK, a potent irreversible neutrophil elastase inhibitor. Moreover, this subfraction displayed no cytotoxicity or phototoxicity and excellent efficacy for the tested anti-ageing properties. Hydrolysable tannins were confirmed as the metabolites behind C. hypocistis skin anti-ageing properties, effectively mitigating critical molecular mechanisms that influence the phenotypically distinct ageing clinical manifestations. Pedunculagin was particularly effective in inhibiting neutrophil elastase, considered one of the most destructive enzymes in skin ageing.

A neutrophil elastase inhibitor, sivelestat, attenuates sepsis-induced acute kidney injury by inhibiting oxidative stress

BackgroundSivelestat, a selective inhibitor of neutrophil elastase (NE), can mitigate sepsis-related acute lung injury. However, the role of sivelestat in inhibiting oxidative stress and attenuating sepsis-related acute kidney injury (AKI) remains unclear. Here, we reported the effects of sivelestat against oxidative stress-induced AKI by suppressing the production of oxidative stress indicators. Materials and methodsA male Sprague-Dawley rat model of sepsis was established by cecal ligation and puncture (CLP). Sivelestat or normal saline was administered into jugular vein with a sustained-release drug delivery system. Indicators of inflammation and AKI, including white blood cells (WBC), neutrophils, lymphocytes, C-reactive proteins (CRP), procalcitonin (PCT), blood urea nitrogen (BUN), creatinine (Cr) and uric acid (UA), were assessed at 24 h post-sivelestat treatment. Indicators of liver injury, including direct bilirubin (DBIL), indirect bilirubin (IBIL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), were also assessed at 24 h post-sivelestat treatment. Indicators of oxidative stress, including superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px), were assessed at 12 h and 24 h post-sivelestat treatment. At 24 h post-sivelestat treatment, H&E staining of kidney and liver tissue was performed to observe pathological alterations. ResultsAt 24 h post normal saline or sivelestat (0.2 g/kg body weight) treatment, WBC, neutrophil, CRP, PCT, MDA, BUN, Cr, UA, AST, ALT, DBIL and IBIL were increased, while SOD and GSH-Px were decreased, in septic rats treated with normal saline compared with that in non-septic rats treated with normal saline (all p < 0.05). The changes of these indicators were reversed in septic rats treated with sivelestat compared with that in septic rats treated with normal saline (all p < 0.05). Similar results were found regarding the levels of oxidative stress indicators at 12 h post-sivelestat treatment. The degenerative histopathological changes in both kidney and liver tissues were ameliorated upon sivelestat treatment. ConclusionsSivelestat plays a protective role in sepsis-related AKI by inhibiting oxidative stress. Our study reveals a possible therapeutic potential of sivelestat for oxidative stress-induced AKI.

Sivelestat (Neutrophil Elastase Inhibitor) as an Anti-inflammatory and Anti-viral Agent: An In Silico Study.

Background Sivelestat is a potent and specific neutrophil elastase inhibitor. It is clinically used in treating lung injury and respiratory distress syndrome. This engaged us to undertake the present study in which sivelestat was studied as an anti-inflammatory and anti-viral agent. Methodology The docking study of sivelestat on matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), chikungunya virus nonstructural protein-2 (CVnsP2) protease, and influenza A (H1N9) virus neuraminidase was assessed using the Chemistry at Harvard Macromolecular Mechanics (CHARMM) Dock (CDOCK) method. Furthermore, molecular physicochemical; bioactivity; absorption, distribution, metabolism, and excretion (ADME); toxicity; and Search Tool for Interacting Chemicals (STITCH) analyses were performed by using the Molinspiration (Molinspiration Cheminformatics, Slovensky Grob, Slovak Republic), SwissADME SwissADME (Swiss Institute of Bioinformatics, Quartier Sorge - Bâtiment Amphipôle, Switzerland), pkCSM (University of Melbourne, Melbourne, Australia), and STITCH-free online tools. Results The molecular physicochemical assessment of the ligand (sivelestat) showed no (zero) violation and agreed with the thumb rule of five, otherwise known as Lipinski's rule of five. ADME prediction of the ligand (sivelestat) is shown to possess a low gastrointestinal absorption (GIA) property. Similarly, toxicity analysis of the ligand (sivelestat) is predicted to have a hepatotoxicity effect. STITCH analysis reveals that the ligand (sivelestat) has exhibited interactions with the three human proteins. Conclusions The present molecular docking studies showed that the ligand (sivelestat) has successfully docked with all four enzymes of interest. Hence, the current finding has provided a good understanding of sivelestat as an effective suppressor activity against all four enzymes: MMP-2, MMP-9, CVnsP2 protease, and influenza neuraminidase.

Otras enfermedades hepáticas de causa genética, metabólica y endocrinológica

Liver diseases of genetic origin comprise a series of diseases that manifest as abnormalities in liver structure and/or function due to genetic mutations. This update will discuss some of them, such as alpha-1 antitrypsin deficiency (A1AT), Wilson's disease, lysosomal acid lipase deficiency (LAL-D), and other congenital diseases related to bile acid and bilirubin metabolism.Alpha-1 antitrypsin deficiency is an autosomal codominant condition characterized by a decrease in secretion of alpha-1 antitrypsin protein, which acts as an inhibitor of neutrophil elastase. This results in liver and lung damage due to an accumulation of misfolded protein in hepatocytes and uncontrolled elastase activity. On the other hand, in Wilson's disease, an autosomal recessive disorder, mutations in the ATP7B gene impair copper metabolism. This results in an accumulation of toxic copper in the liver and other organs, causing hepatitis, cirrhosis, and neuropsychiatric manifestations. Lysosomal acid lipase deficiency is an autosomal recessive disorder caused by mutations in the LIPA gene. This results in the accumulation of cholesterol and triglyceride esters in lysosomes, leading to hepatomegaly, hyperlipidemia, and premature atherosclerosis. Finally, the set of diseases related to bilirubin and bile acid metabolism involve abnormalities in the production, transport, and excretion of bilirubin and bile acids. They are associated with cholestasis and hepatocellular damage, which can lead to liver failure and death.

Targeted Library of Phosphonic-Type Inhibitors of Human Neutrophil Elastase.

Despite many years of research, human neutrophil elastase (HNE) still remains an area of interest for many researchers. This multifunctional representative of neutrophil serine proteases is one of the most destructive enzymes found in the human body which can degrade most of the extracellular matrix. Overexpression or dysregulation of HNE may lead to the development of several inflammatory diseases. Previously, we presented the HNE inhibitor with kinact/KI value over 2,000,000 [M-1s-1]. In order to optimize its structure, over 100 novel tripeptidyl derivatives of α-aminoalkylphosphonate diaryl esters were synthesized, and their activity toward HNE was checked. To confirm the selectivity of the resultant compounds, several of the most active were additionally checked against the two other neutrophil proteases: proteinase 3 and cathepsin G. The developed modifications allowed us to obtain a compound with significantly increased inhibitory activity against human neutrophil elastase with high selectivity toward cathepsin G, but none toward proteinase 3.

Characterization of extracellular trap production and release by equine neutrophils in response to different stimuli

This study explores Neutrophil Extracellular Trap (NET) formation in equine neutrophils, which is crucial for eliminating infections and is implicated in various equine inflammatory diseases. We investigated the molecular pathways involved in NET release by equine neutrophils in response to stimuli. We use PMA, A23187, LPS, PAF, OZ, and cytokines, observing NET release in response to PMA, PAF, and A23187. In contrast, LPS, OZ, and the cytokines tested did not induce DNA release or did not consistently induce citrullination of histone 4. Peptidyl-arginine deiminase inhibition completely halted NET release, while NADPH oxidase and mitochondrial reactive oxygen species only played a role in PMA-induced NETs. Neutrophil elastase inhibition modestly affected PAF-induced NET liberation but not in PMA or A23187-induced NET, while myeloperoxidase did not contribute to NET release. We expect to provide a foundation for future investigations into the role of NETs in equine health and disease and the search for potential therapeutic targets.

Sivelestat in Patients at a High Risk of Postoperative Acute Lung Injury After Scheduled Cardiac Surgery: A Prospective Cohort Study.

Sivelestat, a neutrophil elastase inhibitor, is specifically developed to mitigate the occurrence of acute lung injury (ALI) in individuals who are undergoing cardiovascular surgery. However, its impact on patients who are at a heightened risk of developing ALI after scheduled cardiac surgery has yet to be determined. In order to address this knowledge gap, we undertook a study to assess the efficacy of sivelestat in protecting the lungs of these patients. We conducted a prospective cohort study involving 718 patients who were at high risk of developing postoperative acute lung injury (ALI) and underwent scheduled cardiac surgery between April 25th, 2022, and September 7th, 2023. Among them, 52 patients received sivelestat (administered at a dosage of 0.2mg/kg/h for 3 days), while 666 patients served as controls, not receiving sivelestat. The control conditions were the same for all patients, including ventilation strategy, extubating time, and fluid management. Subsequently, a propensity-score matched cohort was established, consisting of 40 patients in both the sivelestat and control groups. The primary outcome measure encompassed a composite of adverse outcomes, including 30-day mortality, ALI, acute respiratory distress syndrome (ARDS), and others. Secondary outcomes assessed included pneumonia, ventricular arrhythmias, mechanical ventilation (MV) time, and more. After conducting propensity matching in our study, we observed that there were no significant differences in 30-day mortality between the sivelestat and control groups (0% vs 2.5%, P=0.32). However, the use of sivelestat exhibited a significant reduction in the incidence of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) compared to the control group (0% vs 55%, P<0.01), pneumonia (0 vs 37.5%, P<0.01), MV time (median:8 hours, IQR:4-14.8 hours vs median: 15.2 hours, IQR:14-16.3 hours, P<0.01). Compared to the control group, the sivelestat could significantly decrease white cell count (P<0.01), neutrophile percentage (P<0.01) and C-reactive protein (P<0.01) in the period of postoperative 5 days. The prophylactic administration of sivelestat has shown promising results in reducing the occurrence of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) in patients with a heightened risk of developing these conditions after elective cardiac surgery. Our study findings indicate that sivelestat may provide protective effects by suppressing inflammation triggered by neutrophil activation, thereby safeguarding pulmonary function. ChiCTR2200059102, https://www.chictr.org.cn/showproj.html?proj=166643.

Investigating Polypharmacology through Targeting Known Human Neutrophil Elastase Inhibitors to Proteinase 3.

Using a combination of multisite λ-dynamics (MSλD) together with in vitro IC50 assays, we evaluated the polypharmacological potential of a scaffold currently in clinical trials for inhibition of human neutrophil elastase (HNE), targeting cardiopulmonary disease, for efficacious inhibition of Proteinase 3 (PR3), a related neutrophil serine proteinase. The affinities we observe suggest that the dihydropyrimidinone scaffold can serve as a suitable starting point for the establishment of polypharmacologically targeting both enzymes and enhancing the potential for treatments addressing diseases like chronic obstructive pulmonary disease.

Sivelestat ameliorates sepsis-induced myocardial dysfunction by activating the PI3K/AKT/mTOR signaling pathway

The cardioprotective role of sivelestat, a neutrophil elastase inhibitor, has already been demonstrated, but the underlying molecular mechanism remains unclear. This study aimed to explore the mechanism underlying the role of sivelestat in sepsis-induced myocardial dysfunction (SIMD). We found that sivelestat treatment remarkably improved the viability and suppressed the apoptosis of lipopolysaccharide (LPS)-stimulated H9c2 cells. In vivo, sivelestat treatment was associated with an improved survival rate; reduced serum cTnT, TNF-α, IL-1β levels and myocardial TNF-α and IL-1β levels; ameliorated cardiac function and structure; and reduced cardiomyocyte apoptosis. Moreover, sivelestat treatment substantially increased Bcl-2 expression and suppressed caspase-3 and Bax expression in LPS-induced H9c2 cells and in the heart tissues of septic rats. Furthermore, the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/AKT/mTOR) signaling pathway was activated both in vitro and in vivo. The protective effect of sivelestat against SIMD was reversed by the PI3K inhibitor LY294002. In summary, sivelestat can protect against SIMD by activating the PI3K/AKT/mTOR signaling pathway.

TF/PAR2 Signaling Axis Supports the Protumor Effect of Neutrophil Extracellular Traps (NETs) on Human Breast Cancer Cells.

Neutrophil extracellular traps (NETs) have been implicated in several hallmarks of cancer. Among the protumor effects, NETs promote epithelial-mesenchymal transition (EMT) in different cancer models. EMT has been linked to an enhanced expression of the clotting-initiating protein, tissue factor (TF), thus favoring the metastatic potential. TF may also exert protumor effects by facilitating the activation of protease-activated receptor 2 (PAR2). Herein, we evaluated whether NETs could induce TF expression in breast cancer cells and further promote procoagulant and intracellular signaling effects via the TF/PAR2 axis. T-47D and MCF7 cell lines were treated with isolated NETs, and samples were obtained for real-time PCR, flow cytometry, Western blotting, and plasma coagulation assays. In silico analyses were performed employing RNA-seq data from breast cancer patients deposited in The Cancer Genome Atlas (TCGA) database. A positive correlation was observed between neutrophil/NETs gene signatures and TF gene expression. Neutrophils/NETs gene signatures and PAR2 gene expression also showed a significant positive correlation in the bioinformatics model. In vitro analysis showed that treatment with NETs upregulated TF gene and protein expression in breast cancer cell lines. The inhibition of ERK/JNK reduced the TF gene expression induced by NETs. Remarkably, the pharmacological or genetic inhibition of the TF/PAR2 signaling axis attenuated the NETs-induced expression of several protumor genes. Also, treatment of NETs with a neutrophil elastase inhibitor reduced the expression of metastasis-related genes. Our results suggest that the TF/PAR2 signaling axis contributes to the pro-cancer effects of NETs in human breast cancer cells.

Botulinum toxin type A ameliorates rat dorsal root ganglia neuron pyroptosis in postherpetic neuralgia by upregulating cathelicidin antimicrobial peptide to inhibit neutrophil elastase.

Botulinum toxin type A (BoNT/A) has exhibited efficacy in postherpetic neuralgia (PHN) treatment, and this study aims to uncover its underlying mechanisms. Resiniferatoxin (RTX)-induced PHN rats were given BoNT/A. Rat postoperative pain behaviors were assessed by Von Frey test. Cleaved-synaptosomal protein 25 kDa (cl-SNAP-25) or cathelicidin antimicrobial peptide (CAMP) expression in rat dorsal root ganglia (DRG) was detected by immunofluorescence or immunohistochemistry. Healthy rat-derived DRG neurons were transfected, incubated with lipopolysaccharides (LPS)/adenosine 5'-triphosphate (ATP) to stimulate pyroptosis and treated with BoNT/A. The CCK-8, Western blot, ELISA, and qRT-PCR were used to assess the viability, levels of pyroptosis-related proteins proinflammatory cytokine levels, as well as CAMP and ELANE mRNA levels. BoNT/A (30 U/kg) promoted cl-SNAP-25 expression in rat DRG and reversed RTX-induced decrease of rat paw withdrawal thresholds and CAMP expression and increase of pyroptosis-associated protein and inflammatory factor expression in rat DRG. CAMP interacted with ELANE in rat DRG neurons. BoNT/A attenuated LPS/ATP-stimulated inhibition of viability and CAMP expression and upregulation of inflammatory mediators, pyroptosis-related proteins, and ELANE expression in rat DRG neurons, which was counteracted by CAMP silencing. However, ELANE knockdown offset the effect of CAMP silencing in LPS/ATP/BoNT/A-treated rat DRG neurons. On the whole, BoNT/A alleviates rat DRG neuron pyroptosis during PHN by upregulating CAMP to inhibit ELANE.

P-001 - Fluorine-18 Labeling of Neutrophil Elastase Inhibitors

P-001 - Fluorine-18 Labeling of Neutrophil Elastase Inhibitors

Biochemical markers assessing rate of reparative processes in patients with infiltrative pulmonary tuberculosis

Theeffectiveness of chemotherapy for infiltrative pulmonary tuberculosis (ITL) is determined by proper timing and adequacy of treatment. The speed of reparative changes in the pulmonary parenchyma is associated with the effectiveness of therapy. Different classes of proteinases are involved in extracellular matrix remodeling. The aim of the study was to evaluate a potential of using the markers of proteinase/inhibitors axis for predicting effectiveness of therapy in patients with ITL due to varying resistance ofMycobacterium tuberculosisto anti-tuberculosis drugs (PTP).Materials and methods.A retrospective study included 60 and 55 ITL patients with the drug sensitive (DS) and drug resistance (DR) Mtb strains, respectively. Patients were divided into two groups according to therapy effectiveness. The levels of blood serum matrix metalloproteinase MMP-1, MMP-3, MMP-8, MMP-9 and their TIMP-1 inhibitor, neutrophil elastase (NE), alpha-2 macroplobulin (MG) and proteinase inhibitor (PI) were determined. Statistica 10.0 and R software packages were used.Results. According to the model of discriminant analysis, the pattern of host inflammatory response in ITL was accounted for not only by varying pathogen resistance, but also by the different size of lung damage. Patients with a limited and widespread process with the DS of the pathogen strains were assigned to group I and II, and DR — to group III and IV group, respectively. The decisive in the speed of tissue repair was the number of neutrophils bearing various levels of proteinase MMP-8, MMP-9 (I group) or TIMP-1 and PI inhibitors (II group). Only combining biochemical data with the those on radiation methods are possible for prognosis in a group of patients with DR (III and IV).Conclusions.Combinations of the markers of the proteinase/inhibitors axis are informative in assessing a rate of reparative changes in ITL and differ not only depending on the pathogen DS strains, but also from the size of destructed pulmonary parenchyma. Differences in parameter combinations are accounted for by history of a specific disease.

Neutrophil Elastase Catalytic Activity Regulates Granulopoiesis

Heterozygous, autosomal dominantly inherited mutations in the gene, ELANE, encoding the neutrophil granule serine protease, neutrophil elastase, are the cause of cyclic neutropenia and the most common cause of severe congenital neutropenia. Many mutations throughout the protein occur in patients with congenital neutropenia, but they largely spare residues essential for enzymatic catalysis. Decades ago, neutrophil elastase was proposed to function as a chalone, in which its proteolytic activity feeds back to negatively regulate neutrophil production at steady state levels. To further determine if neutrophil elastase catalytic activity contributes to hematopoietic regulation and to evaluate how its mutations cause hereditary neutropenia, we have studied an induced pluripotent stem cell (iPSC) model of hematopoiesis, in which we have employed CRISPR/Cas9 to engineer a mutation not encountered in neutropenic patients. We inactivated neutrophil elastase's catalytic serine residue through substitution with alanine, generated CD34+ cells from iPSC, and directed their differentiation toward the granulocytic lineage. Compared to similarly edited isogenic controls in which the catalytic serine of neutrophil elastase remains intact, iPSC-derived CD34+ cells lacking the catalytic serine grew at a faster rate, failed to down-regulate ELANE expression while cyclically reactivating CD34 expression during granulocytic differentiation, produced greater quantities of neutrophils, and demonstrated residual progenitor cell populations in replating assays. Some, but not all, of these findings were reproducible upon treatment with small molecule inhibitors of neutrophil elastase. These observations suggest that neutrophil elastase's catalytic activity may help regulate granulopoiesis and could explain genotypic differences distinguishing cyclic neutropenia from severe congenital neutropenia.

Neutrophil Elastase is Identified as a Key Regulator of Atherosclerosis and Immune Infiltration by Multi-Omics

Neutrophil elastase is a serine protease. The function of neutrophil elastase in vascular targeted therapies in oncology was analyzed by multi-omics analysis. By comparing the neutrophil elastase mRNA levels in atherosclerotic and normal blood vessels, we observed that neutrophil elastase was elevated in atherosclerotic arteries. The neutrophil elastase mRNA expression level in most tumors was lower than in the adjacent tissues, which is not conducive to the clinical prognosis of extensive tumors. Interestingly, neutrophil elastase was highly expressed in colon cancer, head and neck squamous cell carcinoma, and acute myeloid leukemia. There was a positive relationship between neutrophil elastase and the fibroblast immune invasion of various tumors. Furthermore, we obtained 20 hub genes from Cytoscape and verified their mRNA levels in a mouse model of atherosclerosis. The results showed that they were highly expressed in the arteries of mice with high-fat diet-induced atherosclerosis as well as in human atherosclerotic plaques. Neutrophil elastase inhibitors suppressed the ox-low-density-lipoprotein-induced cathepsin G expression. Neutrophil elastase is not only an important risk factor for atherosclerosis but also an important oncogene and a potentially important target in cancer patients with arterial diseases.

Neutrophil Elastase Inhibition by Sivelestat (ONO-5046) Attenuates AngII-Induced Abdominal Aortic Aneurysms in Apolipoprotein E-Deficient Mice.

Abdominal aortic aneurysm (AAA) is an arterial disease characterized by dilatation of the aortic wall. It has been suggested that neutrophil counts and neutrophil elastase activity are associated with AAA. We investigated whether a neutrophil elastase (NE) inhibitor, sivelestat (Siv), had a protective effect against angiotensin II (AngII)-induced AAAs. Male apolipoprotein E-deficient mice were assigned into three groups: Vehicle + saline, AngII + saline, and AngII + Siv. All mice were administered intraperitoneally with either Siv or vehicle twice daily after AngII infusion. In the 4-week AngII infusion study, plasma NE concentration (P = 0.041) and its activity (P = 0.011) were elevated by AngII. These increases were attenuated by Siv (concentration:P = 0.010, activity:P = 0.027). Further, plasma elastase activity was closely correlated with aortic width (R = 0.6976, P < 0.001). In the 1-week AngII infusion study, plasma and tissue elastase activity increased by AngII (plasma:P = 0.034, tissue:P < 0.001), but were reduced by Siv (plasma:P = 0.014, tissue:P = 0.024). AngII increased aortic width (P = 0.011) but was attenuated by co-administration of Siv (P = 0.022). Moreover, Siv decreased the incidence of AAAs (P = 0.009). Elastin fragmentation induced by AngII was reduced by Siv. Many inflammatory cells that were either CD68 or Gr-1 positive were observed in the AngII + saline group, whereas few inflammatory cells were accumulated in the AngII + Siv group. MMP-2 and MMP-9 were enhanced by AngII, but were reduced by Siv. In vitro, MMP-2 activity was induced by human NE (medium:P < 0.001, cells:P = 0.001), which was attenuated by co-incubation of Siv in medium (P < 0.001) and protein of human aortic smooth muscle cells (P = 0.001). Siv attenuated AngII-induced AAA through the inhibition of NE.

An elastase-inhibiting, plaque-targeting and neutrophil-hitchhiking liposome against atherosclerosis

Neutrophil extracellular traps (NETs) play a crucial role in the formation of vulnerable plaques and the development of atherosclerosis. Alleviating the pathological process of atherosclerosis by efficiently targeting neutrophils and inhibiting the activity of neutrophil elastase to inhibit NETs is relatively unexplored and is considered a novel therapeutic strategy with clinical significance. Sivelestat (SVT) is a second-generation competitive inhibitor of neutrophil elastase with high specificity. However, therapeutic effect of SVT on atherosclerosis is restricted because of the poor half-life and the lack of specific targeting. In this study, we construct a plaque-targeting and neutrophil-hitchhiking liposome (cRGD-SVT-Lipo) to improve the efficacy of SVT in vivo by modifying the cRGD peptide onto SVT loaded liposome, which was based on the interaction between cRGD peptide and integrin ανβ3 on the surface of cells in blood and plaque, including epithelial cell, macrophage and neutrophils. The cRGD-SVT-Lipo could actively tend to or hitchhike neutrophils in situ to reach atherosclerotic plaque, which resulted in enhanced atherosclerotic plaque delivery. The cRGD-SVT-Lipo could also reduce plaque area, stabilize plaque, and ultimately alleviate atherosclerosis progression through efficiently inhibiting the activity of neutrophil elastase in atherosclerotic plaque. Therefore, this study provides a basis and targeting strategy for the treatment of neutrophil-related diseases. Statement of significanceNeutrophil extracellular traps (NETs)-inhibiting is a prospective therapeutic approach for atherosclerosis but has received little attention. The NETs can be inhibited by elastase-restraining. In this work, an intriguing system that delivers Sivelestat (SVT), a predominantly used neutrophil elastase inhibitor with poor targeting capability, is designed to provide the drug with plaque-targeting and neutrophil-hitchhiking capability. The result suggests that this system can effectively hinder the formation of NETs and delay the progression of atherosclerosis.

Lead activates neutrophil degranulation to induce early myocardial injury in mice

Lead (Pb) is a pervasive toxic metal contaminant associated with a high risk of myocardial injury. However, the precise mechanism underlying Pb-induced myocardial injury has yet to be fully elucidated. In this study, a murine model of Pb exposure (0, 1, 5, and 10 mg/kg) was employed to investigate the involvement of neutrophil degranulation in the induction of myocardial injury. Notably, serum levels of cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) increased significantly in Pb-exposed mice, whereas cTnI levels in cardiomyocytes decreased, suggesting that Pb exposure may cause early myocardial injury. Moreover, Pb exposure was found to promote neutrophil degranulation, as evidenced by elevated myeloperoxidase (MPO) and neutrophil elastase (NE) concentrations in both the serum of Pb-exposed workers and Pb-exposed mice, as well as the extracellular supernatant of neutrophils following exposure. However, we found that serum level of cTnI enhanced by Pb exposure is associated with increased NE levels in the serum, but not with MPO levels. Upon treatment with NE inhibitor (sivelestat), the serum level of cTnI markedly reduced in Pb-exposed mice, we found that early myocardial injury is associated with NE levels in the serum. At the molecular level, western blotting analysis revealed an upregulation of ERK1/2 expression in vitro following Pb exposure, suggesting that the activation of the ERK1/2 signaling pathway may underlie the participation of neutrophil degranulation in Pb-induced myocardial injury. In summary, our findings demonstrate that Pb exposure can initiate early myocardial injury by promoting the neutrophil degranulation process, thereby highlighting the potential role of this process in the pathogenesis of Pb-associated myocardial injury.