Elastase Inhibitor Research Articles

Investigation of the effects of antimicrobial peptides and vitamin D in breast cancer

Breast cancer is the most common cancer in women. In recent years, there have been studies on the effectiveness of cathelicidins, one of the antimicrobial peptides, especially in breast cancer. Cathelicidin expression is regulated by a rather complex mechanism. Under normal conditions, vitamin D induces the release of cathelicidin from human neutrophils via Neutrophil Elastase (NE). Elafin, on the other hand, inhibits cathelicidin as a Neutrophil Elastase inhibitor. However, the effect of these molecules on tumor progression is unclear. In our study, we aimed to investigate the effects of vitamin D and Elafin on cathelicidin in breast cancer patients. Cathelicidin, Elafin, and Vitamin D Receptor levels in the pre and post-operative blood samples of control patients and patients diagnosed with breast cancer were analyzed by western blot method. According to our findings, it was observed that cathelicidin levels were especially high and elafin levels were low in the preoperative group. Since an inflammatory environment occurs in the presence of a tumor, there is an increase in vitamin D receptors and elafin in the postoperative group. It was thought that the low Elafin in the preoperative group caused vitamin D to secrete more Cathelicidin and increased the progression of the tumor, but the formation of cathelicidin was inhibited due to the increase in Elafin levels in the postoperative period. Thus, it was concluded that cathelicidin, which has an effect on the development of breast cancer, can be controlled by Elafin and Vitamin D receptors.

A Comprehensive Study on Chemical and Biological Investigation of Thymus Brachychilus Jalas: A Rich Source of Ursolic and Oleanolic Acids

The significance of Thymus species in the scientific community is growing steadily due to their extensive utilization in traditional medicine, food industry, and pharmaceutical sector, owing to their abundance in essential oil and phytochemical content, rendering them commercially significant species. The current work focuses on conducting a comprehensive analysis of the ethanol extract and essential oil derived from the root and aerial portions of Thymus brachychilus Jalas, an endemic species that has not been previously investigated. Additionally, a novel GC-MS (gas chromatography–mass spectrometry) technique was developed to quantify the levels of triterpenoids, which are frequently found in many plants, particularly those belonging to the Lamiaceae family. The approach was then used to assess the triterpenoid content of the species. While the phenolic content of the species was determined by LC-MS/MS (liquid chromatography–tandem mass spectrometry), the chemical composition of triterpenoid, essential oil and flavor (aroma) of the plant was determined by GC-MS. Eucalyptol was the primary ingredient in both the essential oil and the flavor, accounting for 11.05% and 12.35%, respectively. In the DPPH and ABTS radical scavenging techniques, the root ethanol extract exhibited the greatest antioxidant activity with IC50 values of 26.70 ± 0.23 and 19.16 ± 0.11 µg/mL, respectively. There was a high level of urease (59.54 ± 1.67% at 100 µg/mL) inhibitory activity observed in the root ethanol extract in enzyme inhibition assays, as well as angiotensin (94.80 ± 0.56%), elastase (40.19 ± 0.39%), and collagenase (48.26 ± 0.12%) inhibition in the aerial ethanol extract. Moreover, the MCF-7 cell line for breast cancer had a strong cytotoxic impact when exposed to the essential oil of the species (vitality%: 1.45 ± 0.01 at 200 µg/mL. The LC-MS/MS and GC-MS studies revealed that the roots had a significant concentration of rosmarinic acid (15,801 µg analyte/g extract), but the aerial portions had a substantial quantity of ursolic acid (152,374 µg analyte/g extract). The plant exhibits potential in the food, cosmetic, and pharmaceutical sectors on account of its elevated levels of rosmarinic and ursolic acid, superior antioxidant capacity, and angiotensin and urease inhibitory effect.

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.

Promising Anti-Wrinkle Applications of Aromatic Extracts of Hedychium coronarium J. Koenig via Antioxidation and Collagenase Inhibition.

This study aimed to extract aromatic compounds from the rhizomes, leaf sheaths, and leaves of Hedychium coronarium and investigate their chemical compositions, cosmetic/cosmeceutical activities, and irritation potency. The chemical compositions were investigated via gas chromatography-mass spectrometry. The antioxidant activities were evaluated via spectrophotometry. The anti-skin wrinkle properties were investigated via collagenase, elastase, and hyaluronidase inhibition. The irritation potency was observed via a hen's egg-chorioallantoic membrane test. Eucalyptol was detected as a major component in the rhizomes and leaf sheaths, while β-caryophyllene was predominant in the leaves. The absolutes from the rhizomes were the strongest antioxidants, with ABTS scavenging properties similar to L-ascorbic acid. Interestingly, the equivalent concentration (EC1) of the absolute from the rhizome was 0.82 ± 0.01 µg FeSO4/g extract, which was significantly more potent than L-ascorbic acid (0.43 ± 0.03 µg FeSO4/g extract). The rhizome-derived absolute was the most effective against collagenase, while the concretes from the rhizomes and leaf sheaths showed promising anti-hyaluronidase activity with inhibitions of 90.5 ± 1.6% and 87.4 ± 5.1%, respectively. The irritability of the aromatic extracts was not different from that of the vehicle control, proving their safety. Therefore, the Hedychium coronarium rhizome-derived absolute was an attractive and potent antioxidant with anti-collagenase activities, indicating its potential for use in anti-aging formulations.

Chemical annotation of the infusion of Jungia floribunda Less and its inhibitory potential on the elastase enzyme

Jungia floribunda Less. is a shrub belonging to the Asteraceae. The infusion of its leaves has been used, in folk medicine of several South American countries, as anti-inflammatory and hypoglycaemic agent. In the present study, the infusion of leaves from J. floribunda was obtained and its chemical composition was determined by UHPLC-MS associated with molecular network allowing the annotation of flavonoids, sesquiterpene lactones, coumarins, and chlorogenic acid derivatives. Besides, in vitro elastase activity assay was carried out with the infusion. As observed, elastase was inhibited at concentrations ranging from 15 to 240 µg/mL, reaching to 71% of inhibition at the maximum of evaluated concentration. Given that species of plants are promising sources for the discovery of new drugs, these results corroborate the infusion of J. floribunda as a potential source of bioactive compounds for the discovery of new inhibitors for elastase, besides its ethnopharmacological aspects.

Anti-Aging Properties of Temulawak Extract (Curcuma xanthorrhiza L.) by In Vitro Assay

Highlights:1. Elastase, hyaluronidase, and tyrosinase can all be inhibited by temulawak extract.2. Temulawak extract has strong anti-aging ability and can be used as a candidate for cosmetic applications. AbstractThe process of aging is the gradual loss of a tissue's capacity to heal and maintain normal or physiological form and function. Elastase, hyaluronidase, and tyrosinase are the enzymes that contribute to skin aging. The anti-aging effect is connected to the inhibition of these enzymes' activity. Many medicinal plants with active metabolite have been utilized extensively to treat aging. Active compounds of temulawak (Curcuma xanthorrhiza L.) such as phenolic, curcuminoid and xanthorrhizol have potential as antiaging. This study aims to determine whether temulawak extract (TE), a potential candidate for cosmeceutical agent, has anti-aging characteristics by inhibiting the elastase, hyaluronidase, and tyrosinase enzymes. TE was processedxby PT FAST. Stock solution of TE was made by dissolving 20 mg of extract with 1 ml of DMSO 100%, the stock solution was then diluted to achieve the concentrations level 31.25 - 1000 μg/ml working solution of TE. The antiaging activity assays were carried out at PT Aretha Medika Utama. In vitro antiaging assay of TE includes elastase, hyaluronidase, and tyrosinase enzyme inhibition at 7 level of various concentrations of 2.08-66.67 μg/ml for anti-elastase assay, 5.21-166.67 μg/ml for anti-hyaluronidase assay, and 3.125-100 μg/ml for anti-tyrosinase assay with three replications. SPSS software was used to conduct the statistical analysis (p<0,05 is considered significant). TE exhibited highest inhibition percentage of 82.72%, 89.41%, and 94.17% for anti-tyrosinase, anti-elastase, and anti-hyaluronidase, respectively. The median inhibitory concentration (IC50) for elastase inhibitory activity was 10.66 μg/ml, hyaluronidase 70.39 μg/ml, and tyrosinase 55.87 μg/ml. According to this study, TE can be used as cosmeceu

Advances in Sardinian Withania somnifera (L.) Dunal crops through phytochemical and biological approaches

Withania somnifera (L.) Dunal is widely used in the Indian traditional system of medicine to promote general health, wellness, and longevity. Its pharmacological properties are attributed to a group of molecules called withanolides, among which Withaferin A holds great interest for its anti-carcinogenic action. For this reason, numerous studies in recent years have focused on different metabolic or genetic engineering solutions to increase its yield. Here, we present the Sardinian chemotype of Withania somnifera as a potential crop for the extraction of Withaferin A. W. somnifera was cultivated from Sardinian wild germplasm collected in the northeast of the island. After 18 months, the leaves and the roots were collected and their methanolic extract was analyzed by HPLC. 0.3 mg/g DW of Withanolide A (WA), 1.0 mg/g DW of Withanolide B (WB) and 17.7 mg/g DW of Withaferin A (WF) were detected in the leaf sample, while lower values were detected in the roots (0.1 mg/g WF, 0.3 WA mg/g, 0.1 mg/g WB, 0.2 mg/g WO). This research not only confirms the high Withaferin A content found in the wild population leaves, but shows how they are reproducible in cultivated specimens, highlighting Sardinian W. somnifera leaves as a potential source of high-content Withaferin A products. Finally, we focused on the leaves extract by characterizing the phenolic and flavonoid content, as well as the in-vitro antioxidant capacity by DPPH and ABTS assays, revealing a significant amount of phenolic compounds and a related free radical scavenging activity. The leaves extract was further characterized for its anti-aging properties for potential cosmetic application, by the inhibition of tyrosinase, elastase, and collagenase enzymes.

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.

HLDF-6-H Peptide Exhibits an Anti-inflammatory Effect in the Development of Depression in an MPTP Model of Parkinson's Disease

In this work, we investigate the anti-inflammatory effect of the HLDF-6-H peptide (Thr-Gly-Glu-HseHis-Arg) in a model of the presymptomatic stage of Parkinson’s disease (PD). This peptide is a bioactive fragment of the HLDF leukocyte differentiation factor. The presymptomatic stage of PD was modelled by introducing moderate doses of MPTP toxin to C57Bl/6 mice. HLDF-6-H was administered intranasally at a dose of 300 μg/kg daily for three weeks. The severity of depression was determined by the time of immobilization in a Porsolt test. The serum levels of 10 steroids were determined using MS analysis. The activity of inflammatory markers leukocyte elastase (LE) and α1-proteinase inhibitor (α1-PI) was determined using kinetic methods. The development of an inflammatory process under the influence of MPTP is evidenced by an increase in the activity of α1-PI; the anti-inflammatory effect of the peptide is manifested in a decreased activity of LE and α1-PI. At the same time, the immobilization time of mice in a Porsolt test positively correlated with α1-PI and LE, which may indicate the role of inflammation in the development of depression. A positive correlation between estradiol and LE was found in the general sample of mice. In the group of mice treated with the peptide, α1-PI correlated positively with corticosterone and negatively with estradiol and androstenedione. It can be assumed that the anti-inflammatory effect of the peptide is associated with the regulation of corticosteroids and sex hormones. Hence, the applied experimental model confirmed the development of a depressive-like syndrome and neuroendocrine disorders in the presymptomatic stage of PD. The long-term use of HLDF-6-H has antidepressant and anti-inflammatory effects.

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.

Design and synthesis of sirtinol analogs as human neutrophil elastase inhibitors

Human neutrophil elastase (HNE) overexpression has a crucial role in most acute inflammation and alpha1-antitrypsin deficiency syndromes observed in humans, triggering neutrophil invasion and activation of macrophage inflammatory and proteolytic effects, leading to tissue damage. Manipulating HNE level homeostasis could potentially help treat neutrophilic inflammation. Previous studies have shown that sirtinol (1) has a specific influence on HNE and potently attenuates acute lung injury and hepatic injury mediated by lipopolysaccharide or trauma hemorrhage. Therefore, 1 was chosen as the model structure to obtain more potent anti-HNE agents. In the present study, we synthesized a series of sirtinol analogues and determined their inhibitory effects on HNE. Structure-activity relationship (SAR) studies showed that swapping the imine and methyl groups of the sirtinol scaffold with diazene and carboxyl groups, respectively, enhances the HNE inhibiting potency. Compound 29 exhibited the highest potency in the SAR study and showed dual inhibitory effects on HNE and proteinase 3 with IC50 values of 4.91 and 20.69 µM, respectively. Furthermore, 29 was confirmed to have dual impacts on inhibiting O2•− generation and elastase release in cell-based assays with IC50 values of 0.90 and 1.86 µM, respectively. These findings suggest that 29 is a promising candidate for developing HNE inhibitors in the treatment of neutrophilic inflammatory diseases.

Proteomic map of the differentially expressed proteins in the skin of Ctenopharyngodon idella against Aeromonas hydrophila infection

The skin mucus of fish is an important part of the innate immune system, which is poorly understood at the proteomic level. The study established a complete map of the proteins in the skin mucus of Ctenopharangdon idella (C. idella) and discussed the Differentially Expressed Proteins (DEPs) after Aeromonas hydrophila (A. hydrophila) infection. Using Label Free Liquid Chromatography-Mass Spectrometry (LC–MS/MS) analysis, a total of 126 proteins were identified as differentially expressed, 89 proteins of which were upregulated, and 37 proteins were downregulated. Functional annotations of DEPs showed that the upregulated proteins in the skin mucus of the treated group were mostly associated with complement system and cytoskeleton proteins, whereas downregulated proteins were associated with metabolism. The key upregulated immune proteins were transferrin variant C, lysozyme g, annexin A11, 26S proteasome non-ATPase regulatory subunit 8, hypothetical protein ROHU_000884, 60S ribosomal L7a, calpain-2 catalytic subunit-like protein, calpain-9-like protein, complement component C9, complement C3, cathepsin S, cathepsin Z, 14 kDa apolipo, heat shock protein and intelectin, whereas, leukocyte elastase inhibitor, annexin A11, C-factor-like protein, biotinidase isoform X1 and epidermal growth factor receptor substrate 15-like were the downregulated proteins. Moreover, we for the first-time report proteins such as coactosin, lamin-B2 and kelch 12, which were never reported in fish. Our study directly pointing out the possible immunological biomarkers in the skin mucus of C. idella after A. hydrophila treatment. Each of the protein we report in this study could be used as base to establish their mechanism of action during bacterial infection that may contribute to the strategies against bacterial prevention and control in fishes.

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

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

Liposomes as Carriers of GHK-Cu Tripeptide for Cosmetic Application.

Liposomes are self-assembled spherical systems composed of amphiphilic phospholipids. They can be used as carriers of both hydrophobic and hydrophilic substances, such as the anti-aging and wound-healing copper-binding peptide, GHK-Cu (glycyl-L-histidyl-L-lysine). Anionic (AL) and cationic (CL) hydrogenated lecithin-based liposomes were obtained as GHK-Cu skin delivery systems using the thin-film hydration method combined with freeze-thaw cycles and the extrusion process. The influence of total lipid content, lipid composition and GHK-Cu concentration on the physicochemical properties of liposomes was studied. The lipid bilayer fluidity and the peptide encapsulation efficiency (EE) were also determined. Moreover, in vitro assays of tyrosinase and elastase inhibition were performed. Stable GHK-Cu-loaded liposome systems of small sizes (approx. 100 nm) were obtained. The bilayer fluidity was higher in the case of cationic liposomes. As the best carriers, 25 mg/cm3 CL and AL hydrated with 0.5 mg/cm3 GHK-Cu were selected with EE of 31.7 ± 0.9% and 20.0 ± 2.8%, respectively. The obtained results confirmed that the liposomes can be used as carriers for biomimetic peptides such as copper-binding peptide and that the GHK-Cu did not significantly affect the tyrosinase activity but led to 48.90 ± 2.50% elastase inhibition, thus reducing the rate of elastin degeneration and supporting the structural integrity of the skin.

Antimicrobial peptides fight against Pseudomonas aeruginosa at a sub-inhibitory concentration via anti-QS pathway

The broad-spectrum antimicrobial ability of de novo designed amphiphilic antimicrobial peptides (AMPs) G(IIKK)3I-NH2 (G3) and C8-G(IIKK)2I-NH2 (C8G2) have been demonstrated. Nonetheless, their potential as anti-quorum-sensing (anti-QS) agents, particularly against the opportunistic pathogen Pseudomonas aeruginosa at subinhibitory concentrations, has received limited attention. In this study, we proved that treating P. aeruginosa PAO1 with both AMPs at subinhibitory concentrations led to significant inhibition of QS-regulated virulence factors, including pyocyanin, elastase, proteases, and bacterial motility. Additionally, the AMPs exhibited remarkable capabilities in suppressing biofilm formation and their elimination rate of mature biofilm exceeded 95%. Moreover, both AMPs substantially downregulated the expression of QS-related genes. CD analysis revealed that both AMPs induced structural alterations in the important QS-related protein LasR in vitro. Molecular docking results indicated that both peptides bind to the hydrophobic groove of the LasR dimer. Notably, upon mutating key binding sites (D5, E11, and F87) to Ala, the binding efficiency of LasR to both peptides significantly decreased. We revealed the potential of antibacterial peptides G3 and C8G2 at their sub-MIC concentrations as QS inhibitors against P. aeruginosa and elucidated their action mechanism. These findings contribute to our understanding of the therapeutic potential of these peptides in combating P. aeruginosa infections by targeting the QS system.

Dill Extract Preserves Dermal Elastic Fiber Network and Functionality: Implication of Elafin

Introduction: Elastic skin fibers lose their mechanical properties during aging due to enzymatic degradation, lack of maturation, or posttranslational modifications. Dill extract has been observed to increase elastin protein expression and maturation in a 3D skin model, to improve mechanical properties of the skin, to increase elastin protein expression in vascular smooth muscle cells, to preserve aortic elastic lamella, and to prevent glycation. Objective: The aim of the study was to highlight dill actions on elastin fibers during aging thanks to elastase digestion model and the underlying mechanism. Methods: In this study, elastic fibers produced by dermal fibroblasts in 2D culture model were injured by elastase, and we observed the action of dill extract on elastic network by elastin immunofluorescence. Then action of dill extract was examined on mice skin by injuring elastin fibers by intradermal injection of elastase. Then elastin fibers were observed by second harmonic generation microscopy, and their functionality was evaluated by oscillatory shear stress tests. In order to understand mechanism by which dill acted on elastin fibers, enzymatic tests and real-time qPCR on cultured fibroblasts were performed. Results: We evidence in vitro that dill extract is able to prevent elastin from elastase digestion. And we confirm in vivo that dill extract treatment prevents elastase digestion, allowing preservation of the cutaneous elastic network in mice and preservation of the cutaneous elastic properties. Although dill extract does not directly inhibit elastase activity, our results show that dill extract treatment increases mRNA expression of the endogenous inhibitor of elastase, elafin. Conclusion: Dill extract can thus be used to counteract the negative effects of elastase on the cutaneous elastic fiber network through modulation of PI3 gene expression.

Terpenoids as Human Neutrophil Elastase (HNE) Inhibitors: A Comprehensive Review of Natural Anti-inflammatory Isoprenoids.

Human neutrophil elastase (HNE) is an enzyme that plays a key role in the body's inflammatory response. It has been linked to several diseases such as chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. As potential treatments for these diseases, HNE inhibitors are of great interest. Metabolites derived from plants, particularly terpenoids such as β-caryophyllene found in black pepper and other plants, and geraniol present in several essential oils, are recognized as significant sources of inhibitors for HNE. Because of their ability to inhibit HNE, terpenoids are considered promising candidates for developing novel therapies to treat inflammatory conditions such as COPD and emphysema. Furthermore, nature can serve as an excellent designer, and it may offer a safer drug candidate for inhibiting HNE production and activity in the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were searched to get relevant and up-to-date literature on terpenoids as human neutrophil elastase inhibitors. This review focuses on the isolation, chemical diversity, and inhibition of human neutrophil elastase (HNE) of various terpenoids reported from natural sources up to 2022. A total of 251 compounds from various terpenoids classes have been reported. Further, it also provides a summary of HNE inhibitors and includes a thorough discussion on the structure-activity relationship.