Elastase Inhibitor Research Articles

Exploring dermatological applications of Ammoides pusilla essential oil: evaluation of anti-aging, dermatoprotective and antimicrobial properties against dermatopathogenic microorganisms

The aim of this study was the phytochemical characterization of essential oil extracted from the aerial parts (stems, leaves, and flowers) of Ammoides pusilla (Brot.) Breistr (APEO) by use of GC–MS. Importantly, GC–MS results revealed that APEO oil composed of 10 terpene compounds, of which carvacrol (52.84%), d-limonene (17.78%), β-Cymene (13.18%) and γ-Terpinene (8.46%) predominate. These compounds are recognized for their important biological properties. APEO demonstrated remarkable antimicrobial activity, outperforming positive controls in all cases. Inhibition diameters ranged from 30.20 mm against Candida glabrata to 49.80 mm against Candida albicans, with minimum inhibitory concentrations (MICs) ranging from 0.25% against Staphylococcus aureus and Micrococcus luteus to 4.00% against Candida glabrata. This antimicrobial efficacy is attributed to the oil's rich bioactive molecules. The essential oil also showed significant dose-dependent inhibition of anti-tyrosinase activity, with IC50 of 29.59 ± 1.89 µg/mL for monophenolase activity and 17.56 ± 0.76 µg/mL for diphenolase activity. At the same time, APEO showed significant inhibition of elastase, with an IC50 of 20.90 ± 3.16 µg/mL. The sun protection factor (SPF) of the essential oil was determined to be 4.323. This SPF value corresponds to an estimated 76.88% effectiveness in blocking UVB radiation. These results suggest that APEO possesses promising dermatoprotective and anti-aging properties. In conclusion, APEO exhibits notable antimicrobial, anti-tyrosinase and anti-elastase activities, paving the way for new natural therapeutic options for skin problems, with anti-aging and dermatoprotective dermal applications.

Targeting neutrophil serine proteases in bronchiectasis.

Persistent neutrophilic inflammation is a central feature in both the pathogenesis and progression of bronchiectasis (BE). Neutrophils release neutrophil serine proteases (NSPs), such as neutrophil elastase, cathepsin G and proteinase 3. When chronically high levels of free NSP activity exceed those of protective antiproteases, structural lung destruction, mucosal-related defects, further susceptibility to infection and worsening of clinical outcomes can occur. Despite the defined role of prolonged, high levels of NSPs in BE, no drug that controls neutrophilic inflammation is licensed for the treatment of BE. Previous methods of suppressing neutrophilic inflammation (such as direct inhibition of neutrophil elastase) have not been successful; however, an emerging therapy designed to address neutrophil-mediated pathology, inhibition of the cysteine protease cathepsin C (CatC, also known as dipeptidyl peptidase 1), is a promising approach to ameliorate neutrophilic inflammation, since this may reduce the activity of all NSPs implicated in BE pathogenesis, and not just neutrophil elastase. Current data suggest that CatC inhibition may effectively restore the protease-antiprotease balance in BE and improve disease outcomes as a result. Clinical trials for CatC inhibitors in BE have reported positive Phase III results. In this narrative review, we discuss the role of high NSP activity in BE, and how this feature drives the associated morbidity and mortality seen in BE. This review discusses therapeutic approaches aimed at treating neutrophilic inflammation in the BE lung, summarising clinical trial outcomes, and highlighting the need for more treatment strategies that effectively address chronic neutrophilic inflammation in BE.

Computational Approach to Identifying New Chemical Entities as Elastase Inhibitors with Potential Antiaging Effects.

In the aging process, skin morphology might be affected by wrinkle formation due to the loss of elasticity and resilience of connective tissues linked to the cleavage of elastin by the enzymatic activity of elastase. Little information is available about the structural requirements to efficiently inhibit elastase 1 (EC 3.4.21.36) expressed in skin keratinocytes. In this study, a structure-based approach led to the identification to the pharmacophoric hypotheses that described the main structural requirements for binding to porcine pancreatic elastase as a valuable tool for the development of skin therapeutic agents due to its similarity with human elastase 1. The obtained models were subsequently refined through the application of computational alanine-scanning mutagenesis to evaluate the effect of single residues on the binding affinity and protein stability; in turn, molecular dynamic simulations were carried out; these procedures led to a simplified model bearing few essential features, enabling a reliable collection of chemical features for their interactions with elastase. Then, a virtual screening campaign on the in-house library of synthetic compounds led to the identification of a nonpeptide-based inhibitor (IC50 = 60.4 µM) belonging to the class of N-substituted-1H-benzimidazol-2-yl]thio]acetamides, which might be further exploited to obtain more efficient ligands of elastase for therapeutic applications.

Sensitive quantification of fibroblast activation protein and high-throughput screening for inhibition by FDA-approved compounds

Fibroblast activation protein (FAP) has been extensively studied as a cancer biomarker for decades. Recently, small-molecule FAP inhibitors have been widely adopted as a targeting moiety of experimental theranostic radiotracers. Here we present a fast qPCR-based analytical method allowing FAP inhibition screening in a high-throughput regime. To identify clinically relevant compounds that might interfere with FAP-targeted approaches, we focused on a library of FDA-approved drugs. Using the DNA-linked Inhibitor Antibody Assay (DIANA), we tested a library of 2,667 compounds within just a few hours and identified numerous FDA-approved drugs as novel FAP inhibitors. Among these, prodrugs of cephalosporin antibiotics and reverse transcriptase inhibitors, along with one elastase inhibitor, were the most potent FAP inhibitors in our dataset. In addition, by employing FAP DIANA in the quantification mode, we were able to determine FAP concentrations in human plasma samples. Together, our work expands the repertoire of FAP inhibitors, analyzes the potential interference of co-administered drugs with FAP-targeting strategies, and presents a sensitive and low-consumption ELISA alternative for FAP quantification with a detection limit of 50 pg/ml.

Functional Properties and Components of Koenigia alpina Extract.

Koenigia alpina (All.) T.M.Schust. & Reveal (alpine knotweed) is a perennial herb belonging to the Polygonaceae family. Several studies have examined Polygonaceae species' potential applications as cosmeceutical materials; however, the potential of K. alpina as a cosmeceutical has not yet been studied. Hydrogen peroxide (H2O2) and lipopolysaccharide were used to induce an inflammatory response in RAW 264.7 cells. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radicals and H2O2 were used to evaluate the free-radical scavenging activity of K. alpina extract and its protective effect against reactive oxygen species (ROS)-induced cell damage. The whitening, antiaging, and cell proliferation/migration effects of the extracts were evaluated via tyrosinase inhibition, collagenase/elastase inhibition, and wound healing assays, respectively. The anti-inflammatory effect was confirmed by evaluating nitric oxide (NO) production in RAW 264.7 cells. High-performance liquid chromatography (HPLC), UV, and MS/MS were used to determine the main components of the extract and fractions. The ethyl acetate (EA) fraction and its aglycone fraction showed very high free-radical scavenging activities (47.5 and 47.1µg/mL, respectively). The extract/fractions also showed significant tyrosinase inhibition (IC50 = 0.38mg/mL in EA fraction), collagenase inhibition (IC50 = 0.21mg/mL in EA fraction), and elastase inhibition (IC50 = 0.57mg/mL in aglycone fraction). NO production in lipopolysaccharide-induced RAW 264.7 cells was inhibited by the extract/fractions. The extract also promoted the closure of scratch wounds in HaCaT cells. The K. alpina extract/fractions contained cardamonin, quercetin, and quercitrin. K. alpina extracts/fractions showed antioxidant, antiaging, whitening, and anti-inflammatory activities, suggesting they may have potential as antiaging cosmeceuticals.

Active Components and Skin Care Mechanism of Sea Grape (Caulerpa lentillifera) Extract

This study successfully obtained sea grape extract through mechanical extraction methods, which is rich in active components. These primary active ingredients include high concentrations of crude polysaccharides, total phenolics, and flavonoids. Using two zebrafish models, we observed significant skin moisturizing and repair effects of this extract. Further experiments demonstrated its remarkable anti-aging and skin tightening effects through the DPPH method and elastase inhibition assay. Additionally, the extract showed significant anti-inflammatory effects in a model built on 3 dpf (days post fertilization) Tg (corola: EGFP) transgenic zebrafish. The extract’s safety and reliability were confirmed through a final dermal application test on rabbits. Furthermore, we also analyzed the possible mechanism of Caulerpa lentillifera extract skin care. Overall, our research indicates that sea grapes hold tremendous potential as a novel natural ingredient for skincare. It is foreseeable that sea grapes will become an indispensable component in the future medical skincare market.

Multi-step synthesis, kinetics and in silico explorations of indole-Phenyl-1,2,4-triazole Bi-heterocyclic hybrids unified with 3-substituted benzamides as elastase inhibitors

In the present research work, a library of unique indole-phenyltriazole hybrids comprising 3-substituted-benzamide moiety was synthesized through convergent multi-step strategy. The structural confirmation of all synthesized molecules was corroborated by IR, 1H NMR, 13C MMR, EI-MS and CHN analysis data. The results of in vitro inhibitory potential of novel benzamides against elastase enzyme revealed that all molecules were potent inhibitors and 10d was most active compound among them having IC50 value of (0.197 ± 0.027 µM), relative to the standard (13.421 ± 0.016 µM). The Kinetics mechanism analyzed by Lineweaver-Burk plots which exposed that 10d inhibited this enzyme competitively by forming an enzyme-inhibitor complex. The inhibition constant Ki determined from Dixon plot for compound 10d was 0.85 µM. Moreover, cytotoxicity of these compounds was also profiled by hemolytic activity and it was observed that almost all these benzamides compounds displayed low cytotoxicity. These molecules also exhibited mild cytotoxicity toward red blood cell membrane. In addition, the in silico computational explorations fully supported the in vitro enzyme inhibitory results. The binding energy ranges from -7.1 to -9.1 kcal/mol, which showed that compound possessed good interaction tendencies to the pancreatic elastase target protein. So, it was anticipated from the experimental results and computational investigations of the current research that these derivatives might lead to further research gateways for obtaining better and safe nontoxic medicinal scaffolds for dealing with the elastase related ailments such as lungs diseases, pruritic skin disease and liver infection.

In vitro and in silico therapeutic properties of Artepillin C and Aromadendrin as collagenase and elastase inhibitors and investigation of anti-Ovarian cancer effects and antioxidant potential

In this investigation, the enzymes collagenase and elastase were inhibited by artepillin.C and aromadendrin molecules with excellent to good IC50 values of 16.65, and 0.79 μM for artepillin.C and 7.31, 19.38, and 10.56 μM for aromadendrin. Using the molecular modeling study, the chemical activity of these compounds against the enzymes, collagenase, and elastase were evaluated. The anti-cancer properties of the compounds were evaluated using the following cell lines: NIH: OVCAR-3, ES-2, UACC-1598, Hs 832(C).T [Hs832.Tc], TOV-21G, UWB1.289. The DPPH (1,1-diphenyl-2-pricrylhydrazyl) free radical scavenging assay was used to measure antioxidant activity, and the spectrophotometric method was used in this work. The chemical activities of artepillin.C and aromadendrin against collagenase and elastase were investigated utilizing the molecular docking study. The anti-cancer activities of the compounds were evaluated against NIH: OVCAR-3, ES-2, UACC-1598, Hs 832(C).T [Hs832.Tc], TOV-21G, UWB1.289 cell lines. Also, some cell lines had best results for aromadendrin like NIH: OVCAR-3, ES-2, UACC-1598, Hs 832(C).T [Hs832.Tc], TOV-21G, UWB1.289 (10.54 ± 0.94, 22.11 ± 2.52, 31.85 ± 4.73, 8.14 ± 1.52, 17.94 ± 1.88, and 24.31 ± 2.64 μM). The chemical activities of artepillin.C and aromadendrin against some of the expressed surface receptor proteins (folate receptor, CD44, EGFR, Formyl Peptide Receptor–Like 1, M2 muscarinic receptor, and estrogen receptors) in the mentioned cell lines were assessed using the molecular docking calculations. The outcomes provided information on potential interactions and their atomic-level properties. According to the docking scores, the compounds show a high affinity for binding to proteins and enzymes. Furthermore, these substances made good contact with the receptors and enzymes. As a result, these substances may have the ability to suppress cancer cells and enzymes.

Exploring the nutritional biochemical profiles and biological functions in the green microalga <i>Chlorella fusca</i>

<i>Chlorella</i> species of microalgae are utilized in the crop and food industries. The aim of this research was to investigate the metabolite profiles of <i>Chlorella fusca</i> for the first time and evaluate its biological properties. The two ion modes of UPLC-Q-TOF-MS/MS were used to identify a total of 62 components in the methanol extract of <i>C. fusca</i>, with 26 in the negative and 36 in the positive ion mode, including 10 identical ingredients. Fatty acids (negative mode) and combinations of chlorophyll and fatty acids (positive mode) were the most prevalent chemical structures, constituting over 80 and 70% of the total metabolites, respectively, followed by chlorophyll, polar lipids, carotenoids, and fatty alcohols. Moreover, this extract exhibited potent antioxidant and anti-aging benefits in decreasing order of potency at a concentration of 200 μg mL<sup>-1</sup>: tyrosinase inhibition (100%), ABTS radical scavenging (90%), elastase inhibition (88%), and DPPH radical scavenging (34%). Notably, this extract protected the mobility of DNA fragments up to 5 μg mL<sup>-1</sup> (26%), with potential effects (> 60% at 200 μg mL<sup>-1</sup>). These findings suggest that <i>C. fusca</i> may be a promising candidate for applications related to its biological functions, owing to the high accumulation of fatty acids and chlorophyll derivatives.

Current Approaches for the Prevention and Treatment of Acute and Chronic GVHD.

Whereas aGVHD has strong inflammatory components, cGVHD displays autoimmune and fibrotic features; incidence and risk factors are similar but not identical; indeed, the aGVHD is the main risk factor for cGVHD. Calcineurin Inhibitors (CNI) with either Methotrexate (MTX) or Mycophenolate (MMF) still represent the standard prophylaxis in HLA-matched allogeneic stem cell transplantation (HSCT); other strategies focused on ATG, Post-Transplant Cyclophosphamide (PTCy), Abatacept and graft manipulation. Despite the high rate, first-line treatment for aGVHD is represented by corticosteroids, and Ruxolitinib is the standard second-line therapy; investigational approaches include Microbiota transplant and the infusion of Mesenchymal stem cells. GVHD is a pleiotropic disease involving any anatomical district; also, Ruxolitinib represents the standard for steroid-refractory cGVHD in this setting. It is a pleiotropic disease involving any anatomical district; also, Ruxolitinib represents the standard for steroid-refractory cGVHD in this setting. Extracorporeal Photopheresis (ECP) is still an option used for steroid refractoriness or to achieve a steroid-sparing. For Ruxolitinib-refractory cGVHD, Belumosudil and Axatilimab represent the most promising agents. Bronchiolitis obliterans syndrome (BOS) still represents a challenge; among the compounds targeting non-immune effectors, Alvelestat, a Neutrophil elastase inhibitor, seems promising in BOS. Finally, in both aGVHD and cGVHD, the association of biological markers with specific disease manifestations could help refine risk stratification and the availability of reliable biomarkers for specific treatments.

Clinical utility of the neutrophil elastase inhibitor sivelestat for the treatment of ALI/ARDS patients with COVID-19

BackgroundSivelestat, a neutrophil elastase inhibitor, is postulated to mitigate acute lung injury in patients following emergency surgery. However, its efficacy in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) induced by coronavirus disease 2019 (COVID-19) remains uncertain. This study aims to evaluate the pulmonary protective effects of sivelestat in COVID-19 patients with ALI/ARDS. MethodsA retrospective study was conducted involving 2454 COVID-19 patients between October 5, 2022, and February 1, 2023. Of these, 102 patients received sivelestat (0.2 mg/kg/h), while 2352 age- and sex-matched controls were identified. Propensity score matching (PSM) analysis was used to match sivelestat and non-sivelestat subgroups in ratios of 1:1 and 1:3 for sensitivity analysis. The primary outcome was a composite of effective outcomes, including 30-day mortality. Secondary outcomes included changes in partial pressure of arterial oxygen (PaO2), the ratio of PaO2 to the fraction of inspired oxygen (PaO2/FiO2), and various cytokine levels. Safety evaluations included assessments of liver function, kidney function, and leukopenia. ResultsIn the propensity score-matched analysis, the sivelestat group had a higher proportion of severe/critical patients (87.26 % vs. 51.02 %, P < 0.001), more ARDS patients (4.9 % vs. 0.43 %, P < 0.001), and more patients with interstitial lung disease (4.9 % vs. 1.49 %, P = 0.023), but fewer patients with stroke (17.65 % vs. 19.86 %, P < 0.001). Oxygen therapy rates were similar between the groups (79.41 % vs. 80.95 %, P = 0.9). The relative risk reduction in 30-day mortality was 88.45 % (95 % confidence interval [CI] 81.23%–93.21 %) for severe/critical COVID-19 patients treated with sivelestat. Sivelestat significantly decreased cytokine levels of interferon alpha (IFNα), interleukin-1 beta (IL-1β), and interleukin-2 (IL-2).In the sivelestat group, the mortality rate was significantly reduced with standard oxygenation and HFNC therapy(P < 0.05). The treatment with sivelestat did not increase side effects. ConclusionThe administration of the neutrophil elastase inhibitor sivelestat may improve clinical outcomes in COVID-19 patients with ALI/ARDS. These findings suggest that sivelestat could be considered an effective treatment option to alleviate pulmonary inflammatory injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Synthetic Strategies to Prepare Bioactive Lysine and Peptide Conjugates With Triazolium Derivatives

AbstractPeptides conjugated with organic molecules can be useful tools for the development of novel bioactive compounds. The lysine side‐chain is an interesting functional group to act as a linker to connect small molecules in peptide conjugates. Herein we present the design and synthesis of four Safirinium derivatives, their facile conjugation to lysine in solid phase, and incorporation in peptides. The compounds differing in the functionalization of nitrogen N2 of the condensed triazolyl moiety are novel building blocks to design conjugates to perform structure‐activity relationship studies of elastase inhibitors. Consequently, structural investigations of the lysine building blocks and of the corresponding peptide conjugates were performed. We present herein the potential of the Safirinium analogs to act as elastase inhibitors in assays performed on porcine pancreas elastase.

ShSPI Inhibits Thrombosis Formation and Ischemic Stroke In Vivo.

Thrombotic diseases, emerging as a global public health hazard with high mortality and disability rates, pose a significant threat to human health and longevity. Although current antithrombotic therapies are effective in treating these conditions, they often carry a substantial risk of bleeding, highlighting the urgent need for safer therapeutic alternatives. Recent evidence has increasingly pointed to a connection between elastase activity and thrombosis. In the current study, we investigated the antithrombotic effects of ShSPI, an elastase inhibitor peptide derived from the venom of Scolopendra hainanum. Results showed that ShSPI significantly attenuated carrageenan-induced thrombosis in vivo. Furthermore, ShSPI effectively inhibited the carrageenan-induced decrease in serum superoxide dismutase (SOD) activity and increase in prothrombin time, fibrinogen level, and endothelial nitric oxide synthase (eNOS) activity. In addition, ShSPI reduced intracerebral thrombosis and improved functional outcomes following ischemic stroke in a transient middle cerebral artery occlusion (tMCAO) mouse model. Collectively, these findings suggest that ShSPI is a promising candidate for the development of novel thrombotic therapies.

Exploration of novel human neutrophil elastase inhibitors from natural compounds: Virtual screening, in vitro, molecular dynamics simulation and in vivo study

BackgroundHuman neutrophil elastase (HNE) is an important contributor to lung diseases such as acute lung injury (ALI) or acute respiratory distress syndrome. Therefore, this study aimed to identify natural HNE inhibitors with anti-inflammatory activity through machine learning algorithms, in vitro assays, molecular dynamic simulation, and an in vivo ALI assay. MethodsBased on the optimized Discovery Studio two-dimensional molecular descriptors, combined with different molecular fingerprints, six machine learning models were established using the Naïve Bayesian (NB) method to identify HNE inhibitors. Subsequently, the optimal model was utilized to screen 6925 drug-like compounds obtained from the Traditional Chinese Medicine Systems Pharmacy Database and Analysis Platform (TCMSP), followed by ADMET analysis. Finally, 10 compounds with reported anti-inflammatory activity were selected to determine their inhibitory activities against HNE in vitro, and the compounds with the best activity were selected for a 100 ns molecular dynamics simulation and its anti-inflammatory effect was evaluated using Poly (I:C)-induced ALI model. ResultsThe evaluation of the in vitro HNE inhibition efficiency of the 10 selected compounds showed that the flavonoid tricetin had the strongest inhibitory effect on HNE. The molecular dynamics simulation indicated that the binding of tricetin to HNE was relatively stable throughout the simulation. Importantly, in vivo experiments indicated that tricetin treatment substantially improved the Poly (I:C)-induced ALI. ConclusionThe proposed NB model was proved valuable for exploring novel HNE inhibitors, and natural tricetin was screened out as a novel HNE inhibitor, which was confirmed by in vitro and in vivo assays for its inhibitory activities.

Evaluation of Novel Hydrazone‐Imide Hybrid Compound as HNE Inhibitor In Silico: Synthesis, XRD and DFT Analysis

AbstractInvestigation into the interactions between drugs and biomolecules can offer a precise understanding of their biological behaviours in vitro and in vivo, providing crucial insights for designing new drugs. Herein, we report the design, synthesis, and characterization of a bicyclic hydrazone derivative, along with its potential as an inhibitor of human neutrophil elastase (HNE), a critical enzyme in the treatment of acute and chronic lung injuries. We present an improved protocol for the synthesis of the compound using N‐amino‐bicyclo[2.2.1]hept‐5‐ene‐2,endo‐3‐endo‐dicarboximide and 4‐(trifluoromethyl)benzaldehyde through a facile, one‐pot, catalyst‐free synthesis in dry ethanol at reflux temperature. Within 12 hours, bicyclic‐hydrazone derivative was obtained with yields of up to 75 % and was characterized using various spectroscopic techniques and computational analyses based on the DFT approach. In silico ADME/T profile of the compound was evaluated and molecular docking simulation was utilized to predict its potential as a HNE inhibitor. The binding energy values of the THI ligand to the chosen PDB ID: 5ABW, 3Q77, and 2RG3 target proteins were determined as −8.41, −7.20, and −7.27 kcal/mol, respectively. In silico analysis findings indicate that the THI compound has promising drug‐likeness properties and has the potential to be evaluated in the development of new HNE inhibitors.

ESSENTIAL OIL CONTENTS AND BIOLOGICAL ACTIVITIES OF THYMUS CANOVIRIDIS JALAS AND THYMUS SIPYLEUS BOISS.

Objective: Members of the Lamiaceae family are considered to be major sources of bioactive therapeutic agents. Many of them are important medicinal and aromatic plants used in traditional and modern medicine and in the food, cosmetic and pharmaceutical industries. The aim of this study was to investigate in detail the biological activities and chemical composition of the essential oils of Thymus canoviridis Jalas and Thymus sipyleus Boiss. species belonging to the genus Thymus, one of the most important genera of the Lamiaceae family. Material and Method: The essential oil content of the species was determined by GC-MS. Antioxidant activities of the essential oils were determined using lipid peroxidation, DPPH free radical, ABTS cation radical and CUPRAC methods. In addition, cytotoxic activities against breast cancer (MCF-7) and colon cancer (HT-29) cell lines and anticholinesterase (against AChE and BChE enzymes), urease, tyrosinase, elastase, collagenase and angiotensin converting enzyme inhibition activities were determined. Result and Discussion: When the essential oil composition of T. sipyleus was analyzed, the major compounds were 1,8-cineole (eucalyptol) (18.16%), camphor (15.08%) and endo-borneol (11.63%), while T. canoviridis was found to be rich in carvacrol (72.88%). T. canoviridis showed high antioxidant activity in lipid peroxidation (IC50: 45.72±0.12 μg/ml), ABTS (IC50: 6.12±0.03 μg/ml) and CUPRAC (IC50: 5.31±0.01 μg/ml) methods. The selectivities of T. canoviridis and T. sipyleus species against MCF-7 cell line were 4.39 and 6.81, respectively. In the enzyme inhibition studies, both Thymus species showed moderate inhibition activity against BChE enzyme (Inhibition%: 57.88±1.14, 39.21±0.89, respectively). In addition, T. sipyleus showed moderate inhibition of elastase enzyme (Inhibition%: 25.33±0.79). When the results are evaluated in general, it can be said that T. canoviridis essential oil with its rich carvacrol content and high cytotoxic and antioxidant activity can be preferred as a safer and natural option instead of synthetic preservatives in food, pharmaceutical and cosmetic industries to extend shelf life and ensure food safety.

Robustaflavone as a novel scaffold for inhibitors of native and auto-proteolysed human neutrophil elastase

ABSTRACT Human neutrophil elastase (HNE) plays a key role in initiating inflammation in the cardiopulmonary and systemic contexts. Pathological auto-proteolysed two-chain (tc) HNE exhibits reduced binding affinity with inhibitors. Using AutoDock Vina v1.2.0, 66 flavonoid inhibitors, sivelestat and alvelestat were docked with single-chain (sc) HNE and tcHNE. Schrodinger PHASE v13.4.132 was used to generate a 3D-QSAR model. Molecular dynamics (MD) simulations were conducted with AMBER v18. The 3D-QSAR model for flavonoids with scHNE showed r 2 = 0.95 and q 2 = 0.91. High-activity compounds had hydrophobic A/A2 and C/C2 rings in the S1 subsite, with hydrogen bond donors at C5 and C7 positions of the A/A2 ring, and the C4’ position of the B/B1 ring. All flavonoids except robustaflavone occupied the S1’-S2’ subsites of tcHNE with decreased AutoDock binding affinities. During MD simulations, robustaflavone remained highly stable with both HNE forms. Principal Component Analysis suggested that robustaflavone binding induced structural stability in both HNE forms. Cluster analysis and free energy landscape plots showed that robustaflavone remained within the sc and tcHNE binding site throughout the 100 ns MD simulation. The robustaflavone scaffold likely inhibits both tcHNE and scHNE. It is potentially superior to sivelestat and alvelestat and can aid in developing therapeutics targeting both forms of HNE.

GC-MS-MS analysis and biological properties determination of Mentha piperita L., essential oils

This research explores the therapeutic properties and medicinal potential of Mentha piperita L. (M. piperita) essential oil (EO) (MPEO) harvested in the province of Ouezzane, northwestern Morocco. We conducted a comprehensive chemical composition analysis of MPEO using gas chromatography-mass spectrometry (GC-MS) to identify its major components. The predominant constituents were pulegone (17.56%), mintlactone (10.62%), D-carvone (9.24%), eucalyptol (7.53%), and thymol (6.06%). The antidiabetic effects were assessed by measuring the inhibition of two digestive enzymes (α-glucosidase and α-amylase). The dermatoprotective effect was evaluated based on the inhibition of elastase and tyrosinase, and neuroprotective activity was studied by examining the inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Additionally, molecular docking analysis was used to determine the interactions between the main MPEO compounds and the enzymes targeted. Antioxidant activity was estimated using in vitro FRAP, DPPH, and ABTS assays. Furthermore, the antibacterial potential was evaluated against pathogenic strains using the micro-broth dilution method. Our results indicate significant antioxidant and neuroprotective activities of MPEO, along with promising antidiabetic and dermatoprotective potential, surpassing references. Additionally, all bacterial strains tested were susceptible to MPEO, with MIC values lower than those of MBC for all bacteria except L. monocytogenes. These in vitro findings were supported by in silico analysis, showing that menthelactone and pulegone presented strong binding affinities with key enzymes involved in glucose regulation and pigmentation. MPEO, rich in bioactive compounds, has shown promising potential. The main components of this oil offer innovative prospects for the development of drugs and natural therapeutic applications.

Progesterone modulates the immune microenvironment to suppress ovalbumin-induced airway inflammation by inhibiting NETosis

Studies have demonstrated that prior to puberty, girls have a lower incidence and severity of asthma symptoms compared to boys. This study aimed to explore the role of progesterone (P4), a sex hormone, in reducing inflammation and altering the immune microenvironment in a mouse model of allergic asthma induced by OVA. Female BALB/c mice with or without ovariectomy to remove the influence of sex hormones were used for the investigations. Serum, bronchoalveolar lavage fluid (BALF), and lung tissue samples were collected for analysis. The results indicated that P4 treatment was effective in decreasing inflammation and mucus secretion in the lungs of OVA-induced allergic asthma mice. P4 treatment also reduced the influx of inflammatory cells into the BALF and increased the levels of Th1 and Th17 cytokines while decreasing the levels of Th2 and Treg cytokines in both BALF and lung microenvironment CD45+ T cells. Furthermore, P4 inhibited the infiltration of inflammatory cells into the lungs, suppressed NETosis, and reduced the number of pulmonary CD4+ T cells while increasing the number of regulatory T cells. The neutrophil elastase inhibitor GW311616A also suppressed airway inflammation and mucus production and modified the secretion of immune Th1, Th2, Th17, and Treg cytokines in lung CD45+ immune cells. These changes led to an alteration of the immunological milieu with increased Th1 and Th17 cells, accompanied by decreased Th2, Treg, and CD44+ T cells, similar to the effects of P4 treatment. Treatment with P4 inhibited NETosis by suppressing the p38 pathway activation, leading to reduced reactive oxygen species production. Moreover, P4 treatment hindered the release of double-stranded DNA during NETosis, thereby influencing the immune microenvironment in the lungs. These findings suggest that P4 treatment may be beneficial in reducing inflammation associated with allergic asthma by modulating the immune microenvironment. In conclusion, this research indicates the potential of P4 as a therapeutic agent for ameliorating inflammation in OVA-induced allergic asthma mice.

Enhancement of high-density lipoprotein-associated protease inhibitor activity prevents atherosclerosis progression

Background and aimsInflammatory cells within atherosclerotic lesions secrete proteolytic enzymes that contribute to lesion progression and destabilization, increasing the risk for an acute cardiovascular event. Elastase is a serine protease, secreted by macrophages and neutrophils, that may contribute to the development of unstable plaque. We previously reported interaction of endogenous protease-inhibitor proteins with high-density lipoprotein (HDL), including alpha-1-antitrypsin, an inhibitor of elastase. These findings support a potential role for HDL as a modulator of protease activity. In this study, we test the hypothesis that enhancement of HDL-associated elastase inhibitor activity is protective against atherosclerotic lesion progression. MethodsWe designed an HDL-targeting protease inhibitor (HTPI) that binds to HDL and confers elastase inhibitor activity. Lipoprotein binding and the impact of HTPI on atherosclerosis were examined using mouse models. Histology and immunofluorescence staining of aortic root sections were used to examine the impact of HTPI on lesion morphology and inflammatory features. ResultsHTPI is a small (1.6 kDa) peptide with an elastase inhibitor domain, a soluble linker, and an HDL-targeting domain. When incubated with human plasma ex vivo, HTPI predominantly binds to HDL. Intravenous administration of HTPI to mice resulted in its binding to plasma HDL and increased elastase inhibitor activity on isolated HDL. Accumulation of HTPI within plaque was observed after administration to Apoe−/− mice. To examine the effect of HTPI treatment on atherosclerosis, prevention and progression studies were performed using Ldlr−/− mice fed Western diet. In both study designs, HTPI-treated mice had reduced lipid deposition in plaque. ConclusionsThese data support the hypothesis that HDL-associated anti-elastase activity can improve the atheroprotective potential of HDL and highlight the potential utility of HDL enrichment with anti-protease activity as an approach for stabilization of atherosclerotic lesions.