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1.
Cureus ; 16(7): e63723, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39099955

ABSTRACT

Paradoxical herniation is a dreadful neurosurgical complication often underdiagnosed, which typically becomes evident over the course of weeks to months after the initial intervention. Here we present a unique case with manifestations in the post-operative period. A patient initially referred to neurosurgery for a meningioma underwent an uneventful surgical excision, followed by the transient placement of a lumbar drain for 48 hours. On the first post-operative day, the patient exhibited progressively altered neurological status, with corresponding imaging revealing a transfalcine herniation, necessitating emergent decompressive craniectomy. Despite the medical and surgical interventions, there were continuous signs of neurological and imaging worsening, with increase in herniation, which led to the diagnosis suspicion of a paradoxical brain herniation. Consequently, a rapid reversal of neurological deficits was observed after applying maneuvers to augment the intracranial pressure, followed by cranioplasty. This case illustrates the utmost importance of clinical suspicion for the uncommon complications of neurointerventions.

2.
Antioxidants (Basel) ; 13(8)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39199196

ABSTRACT

Plant leaves are a source of essential phenolic compounds, which have numerous health benefits and can be used in multiple applications. While various techniques are available for recovering bioactive compounds from by-products, more data are needed on enzyme-assisted extraction (EAE). The aim of this study was to compare EAE and solid-liquid extraction (SLE), to evaluate the impact on bioactive compounds' extraction yield, phytochemical composition, and the antioxidant, antimicrobial, and antidiabetic properties of Aralia cordata leaves and roots, sea buckthorn Hippophae rhamnoides, and hemp Cannabis sativa leaves. The results indicate that EAE with Viscozyme L enzyme (EAE_Visc) extracts of the tested plant leaves possess the highest yield, antioxidant activity, and total phenolic content. Moreover, the EAE_Visc extract increased by 40% the total sugar content compared to the control extract of A. cordata root. Interestingly, the sea buckthorn leaf extracts exhibited α-glucosidase inhibitory activity, which reached an almost 99% inhibition in all extracts. Furthermore, the sea buckthorn leaves SLE and EAE_Visc extracts possess antibacterial activity against Staphylococcus aureus. Additionally, scanning electron microscopy was used to examine changes in cell wall morphology after EAE. Overall, this study shows that EAE can be a promising method for increasing the yield and improving the functional properties of the resulting extracts in a fast and sustainable way compared to SLE.

3.
Drug Discov Today ; 29(9): 104130, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39103143

ABSTRACT

Prostate cancer (PCa) is one of the leading cancers in men and the lack of suitable biomarkers or their modulators results in poor prognosis. Membrane proteins (MPs) have a crucial role in the development and progression of PCa and can be attractive therapeutic targets. However, experimental limitations in targeting MPs hinder effective biomarker and inhibitor discovery. To overcome this barrier, computational methods can yield structural insights and screen large libraries of compounds, accelerating lead identification and optimization. In this review, we examine current breakthroughs in computer-aided drug design (CADD), with emphasis on structure-based approaches targeting the most relevant membrane-bound PCa biomarkers.


Subject(s)
Biomarkers, Tumor , Drug Design , Membrane Proteins , Prostatic Neoplasms , Humans , Prostatic Neoplasms/drug therapy , Male , Membrane Proteins/metabolism , Membrane Proteins/antagonists & inhibitors , Biomarkers, Tumor/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/chemistry , Computer-Aided Design , Animals
4.
Biophys Chem ; 314: 107308, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39208499

ABSTRACT

The human transmembrane protein Transferrin Receptor-1 is regarded as a promising target for the systemic delivery of therapeutic agents, particularly of nucleic acid therapeutics, such as short double stranded RNAs. This ubiquitous receptor is involved in cellular iron uptake, keeping intracellular homeostasis. It is overexpressed in multiple cancer cell types and is internalized via clathrin-mediated endocytosis. In previous studies, a human transferrin receptor-1 RNA aptamer, identified as TR14 ST1-3, was shown to be capable of effectively internalizing into cells in culture and to deliver small, double stranded RNAs in vitro and in vivo, via systemic administration. To understand, at the molecular level, the aptamer binding to the receptor and the impact of conjugation with the therapeutic RNA, a multi-level in silico protocol was employed, including protein-aptamer docking, molecular dynamics simulations and free energy calculations. The competition for the binding pocket, between the aptamer and the natural ligand human Transferrin, was also evaluated. The results show that the aptamer binds to the same region as Transferrin, with residues from the helical domain showing a critical role. Moreover, the conjugation to the therapeutic RNA, was shown not to affect aptamer binding. Overall, this study provides an atomic-level understanding of aptamer association to human Transferrin Receptor-1 and of its conjugation with a short model-therapeutic RNA, providing also important clues for futures studies aiming to deliver other oligonucleotide-based therapeutics via Transferrin Receptor.


Subject(s)
Aptamers, Nucleotide , Molecular Dynamics Simulation , Receptors, Transferrin , Receptors, Transferrin/metabolism , Receptors, Transferrin/chemistry , Humans , Aptamers, Nucleotide/chemistry , Aptamers, Nucleotide/metabolism , Molecular Docking Simulation , Binding Sites , Thermodynamics , Protein Binding , Transferrin/chemistry , Transferrin/metabolism , RNA/metabolism , RNA/chemistry , Computer Simulation , Antigens, CD
5.
Front Chem ; 12: 1379914, 2024.
Article in English | MEDLINE | ID: mdl-39170866

ABSTRACT

The rise of antibiotic-resistant bacterial strains has become a critical health concern. According to the World Health Organization, the market introduction of new antibiotics is alarmingly sparse, underscoring the need for novel therapeutic targets. The LytR-CpsA-Psr (LCP) family of proteins, which facilitate the insertion of cell wall glycopolymers (CWGPs) like teichoic acids into peptidoglycan, has emerged as a promising target for antibiotic development. LCP proteins are crucial in bacterial adhesion and biofilm formation, making them attractive for disrupting these processes. This study investigated the structural and functional characteristics of the LCP domain of LytR from Streptococcus dysgalactiae subsp. dysgalactiae. The protein structure was solved by X-ray Crystallography at 2.80 Å resolution. Small-angle X-ray scattering (SAXS) data were collected to examine potential conformational differences between the free and ligand-bound forms of the LytR LCP domain. Additionally, docking and molecular dynamics (MD) simulations were used to predict the interactions and conversion of ATP to ADP and AMP. Experimental validation of these predictions was performed using malachite green activity assays. The determined structure of the LCP domain revealed a fold highly similar to those of homologous proteins while SAXS data indicated potential conformational differences between the ligand-free and ligand-bound forms, suggesting a more compact conformation during catalysis, upon ligand binding. Docking and MD simulations predicted that the LytR LCP domain could interact with ADP and ATP and catalyze their conversion to AMP. These predictions were experimentally validated by malachite green activity assays, confirming the protein's functional versatility. The study provides significant insights into the structural features and functional capabilities of the LCP domain of LytR from S. dysgalactiae subsp. dysgalactiae. These findings pave the way for designing targeted therapies against antibiotic-resistant bacteria and offer strategies to disrupt bacterial biofilm formation.

6.
Molecules ; 29(14)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-39064864

ABSTRACT

Residual melon by-products were explored for the first time as a bioresource of microcrystalline cellulose (MCC) obtention. Two alkaline extraction methods were employed, the traditional (4.5% NaOH, 2 h, 80 °C) and a thermo-alkaline in the autoclave (2% NaOH, 1 h, 100 °C), obtaining a yield of MCC ranging from 4.76 to 9.15% and 2.32 to 3.29%, respectively. The final MCCs were characterized for their chemical groups by Fourier-transform infrared spectroscopy (FTIR), crystallinity with X-ray diffraction, and morphology analyzed by scanning electron microscope (SEM). FTIR spectra showed that the traditional protocol allows for a more effective hemicellulose and lignin removal from the melon residues than the thermo-alkaline process. The degree of crystallinity of MCC ranged from 51.51 to 61.94% and 54.80 to 55.07% for the thermo-alkaline and traditional processes, respectively. The peaks detected in X-ray diffraction patterns indicated the presence of Type I cellulose. SEM analysis revealed microcrystals with rough surfaces and great porosity, which could remark their high-water absorption capacity and drug-carrier capacities. Thus, these findings could respond to the need to valorize industrial melon by-products as raw materials for MCC obtention with potential applications as biodegradable materials.


Subject(s)
Cellulose , Cucurbitaceae , X-Ray Diffraction , Cellulose/chemistry , Cucurbitaceae/chemistry , Spectroscopy, Fourier Transform Infrared
7.
Food Chem ; 460(Pt 1): 140414, 2024 Dec 01.
Article in English | MEDLINE | ID: mdl-39084103

ABSTRACT

Opuntia plants are abundant but still underexplored edible resources of the Algerian region. This work chemically characterizes extracts of different parts of the fruit of the commercial Opuntia ficus-indica (L.) Mill. and the wild Opuntia stricta (Haw.) Haw. growing in Bejaia, and evaluates their anti-inflammatory potential through different cell and cell-free bioassays. The LC-ESI-UHR-QqTOF-MS/MS analysis enabled the identification of 18 compounds, with azelaic acid and 1-O-vanilloyl-ß-d-glucose reported here for the first time. Aqueous extracts of seeds were the most effective in scavenging superoxide anion radical (IC50 = 111.08 µg/mL) and presented the best anti-inflammatory potential in LPS-stimulated macrophages (IC50 = 206.30 µg/mL). The pulp of O. stricta suggested potential for addressing post-inflammatory hyperpigmentation, with piscidic and eucomic acids predicted with the strongest binding affinity towards tyrosinase, exhibiting higher scoring values than the reference inhibitor kojic acid. This pioneer study brings valuable perspectives for the pharmacological, nutritional and economic valorization of the wild O. stricta for functional foods.


Subject(s)
Anti-Inflammatory Agents , Fruit , Opuntia , Plant Extracts , Tandem Mass Spectrometry , Opuntia/chemistry , Fruit/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Algeria , Animals , Mice , Macrophages/drug effects , Macrophages/immunology , RAW 264.7 Cells , Humans , Chromatography, High Pressure Liquid , Spectrometry, Mass, Electrospray Ionization
8.
J Mol Model ; 30(8): 261, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985223

ABSTRACT

CONTEXT: Multiwalled carbon nanotubes (MWCNTs) functionalized with lysine via 1,3-dipolar cycloaddition and conjugated to galactose or mannose are potential nanocarriers that can effectively bind to the lectin receptor in MDA-MB-231 or MCF-7 breast cancer cells. In this work, a method based on molecular dynamics (MD) simulation was used to predict the interaction of these functionalized MWCNTs with doxorubicin and obtain structural evidence that allows a better understanding of the drug loading and release process. The MD simulations showed that while doxorubicin only interacted with pristine MWCNTs through π-π stacking interactions, functionalized MWCNTs were also able to establish hydrogen bonds, suggesting that the functionalized groups improve doxorubicin loading. Moreover, the elevated adsorption levels observed for functionalized nanotubes further support this enhancement in loading efficiency. MD simulations also shed light on the intratumoral pH-specific release of doxorubicin from functionalized MWCNTs, which is induced by protonation of the daunosamine moiety. The simulations show that this change in protonation leads to a lower absorption of doxorubicin to the MWCNTs. The MD studies were then experimentally validated, where functionalized MWCNTs showed improved dispersion in aqueous medium compared to pristine MWCNTs and, in agreement with the computational predictions, increased drug loading capacity. Doxorubicin-loaded functionalized MWCNTs demonstrated specific release of doxorubicin in tumor microenvironment (pH = 5.0) with negligible release in the physiological pH (pH = 7.4). Furthermore, doxorubicin-free MWNCT nanoformulations exhibited insignificant cytotoxicity. The experimental studies yielded nearly identical results to the MD studies, underlining the usefulness of the method. Our functionalized MWCNTs represent promising non-toxic nanoplatforms with enhanced aqueous dispersibility and the potential for conjugation with ligands for targeted delivery of anti-cancer drugs to breast cancer cells. METHODS: The computational model of a pristine carbon nanotube was created with the buildCstruct 1.2 Python script. The lysinated functionalized groups were added with PyMOL and VMD. The carbon nanotubes and doxorubicin molecules were parameterized using the general AMBER force field, and RESP charges were determined using Gaussian 09. Molecular dynamics simulations were carried out with the AMBER 20 software package. Adsorption levels were calculated using the water-shell function of cpptraj. Cytotoxicity was evaluated via a MTT assay using MDA-MB-231 and MCF-7 breast cancer cells. Drug uptake of doxorubicin and doxorubicin-loaded MWCNTs was measured by fluorescence microscopy.


Subject(s)
Doxorubicin , Molecular Dynamics Simulation , Nanotubes, Carbon , Doxorubicin/chemistry , Doxorubicin/pharmacology , Doxorubicin/administration & dosage , Nanotubes, Carbon/chemistry , Humans , Lysine/chemistry , Drug Carriers/chemistry , MCF-7 Cells , Drug Delivery Systems , Drug Liberation , Cell Line, Tumor , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/pharmacology , Antibiotics, Antineoplastic/administration & dosage
9.
Appl Microbiol Biotechnol ; 108(1): 368, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860989

ABSTRACT

The increasing applications for eicosapentaenoic acid (EPA) and the potential shortfall in supply due to sustainability and contamination issues related with its conventional sources (i.e., fish oils; seafood) led to an extensive search for alternative and sustainable sources, as well as production processes. The present mini-review covers all the steps involved in the production of EPA from microorganisms, with a deeper focus on microalgae. From production systems to downstream processing, the most important achievements within each area are briefly highlighted. Comparative tables of methodologies are also provided, as well as additional references of recent reviews, so that readers may deepen their knowledge in the different issues addressed. KEY POINTS: • Microorganisms are more sustainable alternative sources of EPA than fish. • Due to the costly separation from DHA, species that produce only EPA are preferable. • EPA production can be optimised using non-genetic and genetic tailoring engineering.


Subject(s)
Eicosapentaenoic Acid , Microalgae , Eicosapentaenoic Acid/biosynthesis , Eicosapentaenoic Acid/metabolism , Microalgae/metabolism , Bacteria/metabolism , Bacteria/genetics
10.
Am J Med Genet C Semin Med Genet ; : e32089, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38884529

ABSTRACT

Blepharophimosis with intellectual disability (BIS) is a recently recognized disorder distinct from Nicolaides-Baraister syndrome that presents with distinct facial features of blepharophimosis, developmental delay, and intellectual disability. BIS is caused by pathogenic variants in SMARCA2, that encodes the catalytic subunit of the superfamily II helicase group of the BRG1 and BRM-associated factors (BAF) forming the BAF complex, a chromatin remodeling complex involved in transcriptional regulation. Individuals bearing variants within the bipartite nuclear localization (BNL) signal domain of ADNP present with the neurodevelopmental disorder known as Helsmoortel-Van Der Aa Syndrome (HVDAS). Distinct DNA methylation profiles referred to as episignatures have been reported in HVDAS and BAF complex disorders. Due to molecular interactions between ADNP and BAF complex, and an overlapping craniofacial phenotype with narrowing of the palpebral fissures in a subset of patients with HVDAS and BIS, we hypothesized the possibility of a common phenotype-specific episignature. A distinct episignature was shared by 15 individuals with BIS-causing SMARCA2 pathogenic variants and 12 individuals with class II HVDAS caused by truncating pathogenic ADNP variants. This represents first evidence of a sensitive phenotype-specific episignature biomarker shared across distinct genetic conditions that also exhibit unique gene-specific episignatures.

11.
FEBS Lett ; 598(13): 1655-1666, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38750637

ABSTRACT

Cymoxanil (CYM) is a widely used synthetic acetamide fungicide, but its biochemical mode of action remains elusive. Since CYM inhibits cell growth, biomass production, and respiration in Saccharomyces cerevisiae, we used this model to characterize the effect of CYM on mitochondria. We found it inhibits oxygen consumption in both whole cells and isolated mitochondria, specifically inhibiting cytochrome c oxidase (CcO) activity during oxidative phosphorylation. Based on molecular docking, we propose that CYM blocks the interaction of cytochrome c with CcO, hampering electron transfer and inhibiting CcO catalytic activity. Although other targets cannot be excluded, our data offer valuable insights into the mode of action of CYM that will be instrumental in driving informed management of the use of this fungicide.


Subject(s)
Electron Transport Complex IV , Fungicides, Industrial , Mitochondria , Molecular Docking Simulation , Saccharomyces cerevisiae , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/enzymology , Electron Transport Complex IV/metabolism , Electron Transport Complex IV/antagonists & inhibitors , Fungicides, Industrial/pharmacology , Fungicides, Industrial/toxicity , Mitochondria/drug effects , Mitochondria/metabolism , Oxygen Consumption/drug effects , Oxidative Phosphorylation/drug effects , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/antagonists & inhibitors
12.
Appl Microbiol Biotechnol ; 108(1): 329, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38727750

ABSTRACT

Xylanases are key biocatalysts in the degradation of the ß-1,4-glycosidic linkages in the xylan backbone of hemicellulose. These enzymes are potentially applied in a wide range of bioprocessing industries under harsh conditions. Metagenomics has emerged as powerful tools for the bioprospection and discovery of interesting bioactive molecules from extreme ecosystems with unique features, such as high temperatures. In this study, an innovative combination of function-driven screening of a compost metagenomic library and automatic extraction of halo areas with in-house MATLAB functions resulted in the identification of a promising clone with xylanase activity (LP4). The LP4 clone proved to be an effective xylanase producer under submerged fermentation conditions. Sequence and phylogenetic analyses revealed that the xylanase, Xyl4, corresponded to an endo-1,4-ß-xylanase belonging to glycosyl hydrolase family 10 (GH10). When xyl4 was expressed in Escherichia coli BL21(DE3), the enzyme activity increased about 2-fold compared to the LP4 clone. To get insight on the interaction of the enzyme with the substrate and establish possible strategies to improve its activity, the structure of Xyl4 was predicted, refined, and docked with xylohexaose. Our data unveiled, for the first time, the relevance of the amino acids Glu133 and Glu238 for catalysis, and a close inspection of the catalytic site suggested that the replacement of Phe316 by a bulkier Trp may improve Xyl4 activity. Our current findings contribute to enhancing the catalytic performance of Xyl4 towards industrial applications. KEY POINTS: • A GH10 endo-1,4-ß-xylanase (Xyl4) was isolated from a compost metagenomic library • MATLAB's in-house functions were developed to identify the xylanase-producing clones • Computational analysis showed that Glu133 and Glu238 are crucial residues for catalysis.


Subject(s)
Composting , Endo-1,4-beta Xylanases , Escherichia coli , Metagenomics , Phylogeny , Endo-1,4-beta Xylanases/genetics , Endo-1,4-beta Xylanases/metabolism , Endo-1,4-beta Xylanases/chemistry , Endo-1,4-beta Xylanases/isolation & purification , Escherichia coli/genetics , Escherichia coli/metabolism , Metagenome , Gene Library , Soil Microbiology , Xylans/metabolism , Cloning, Molecular , Fermentation , Gene Expression , Molecular Docking Simulation
13.
Adv Ther ; 41(7): 2545-2558, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38748332

ABSTRACT

Achondroplasia is a lifelong condition requiring lifelong management. There is consensus that infants and children with achondroplasia should be managed by a multidisciplinary team experienced in the condition. However, many people are lost to follow-up after the transition from paediatric to adult care, and there is no standardised approach for management in adults, despite the recent availability of international consensus guidelines. To address this, the European Achondroplasia Forum has developed a patient-held checklist to support adults with achondroplasia in managing their health. The checklist highlights key symptoms of spinal stenosis and obstructive sleep apnoea, both among the most frequent and potentially severe medical complications in adults with achondroplasia. The checklist acts as a framework to support individuals and their primary care provider in completing a routine review. General advice on issues such as blood pressure, pain, hearing, weight, adaptive aids, and psychosocial aspects are also included. The checklist provides key symptoms to be aware of, in addition to action points so that people can approach their primary care provider and be directed to the appropriate specialist, if needed. Additionally, the European Achondroplasia Forum offers some ideas on implementing the checklist during the transition from paediatric to adult care, thus ensuring the existing multidisciplinary team model in place during childhood can support in engaging individuals and empowering them to take responsibility for their own care as they move into adulthood.


Subject(s)
Achondroplasia , Adult , Humans , Achondroplasia/complications , Achondroplasia/therapy , Checklist , Europe , Sleep Apnea, Obstructive/therapy , Spinal Stenosis/therapy , Spinal Stenosis/complications , Transition to Adult Care
14.
J Pediatr Genet ; 13(1): 43-49, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38567179

ABSTRACT

Vitamin D-dependent type 1A rickets (VDDR-1A) is a rare autosomal recessive disease due to the inability to convert 25-hydroxyvitamin D [25(OH)D] to the active form 1.25-dihydroxyvitamin D [1.25(OH) 2 D] by the enzyme 25(OH)D-1α-hydroxylase leading to low or low-normal serum levels of [1.25(OH) 2 D]. We report two sisters with rickets in whom the diagnosis of VDDR-1A was a challenge. They had normal 1.25(OH)2D levels, which are unusual with this condition but may be explained by the identified genotype. Both have compound heterozygous for two, most likely, hypomorphic CYP27B1 alleles: the novel p.(Arg117Gly) variant, and p.(Ala129Thr), which are present in 0.43% of the African population. This report illustrates the variability of clinical, laboratory, and radiological presentation between two sisters with the same genotype, during phases of faster or slower growth. Genetic testing was crucial for establishing the diagnosis that optimized the management and genetic counseling.

15.
J Appl Microbiol ; 135(5)2024 May 01.
Article in English | MEDLINE | ID: mdl-38587815

ABSTRACT

AIMS: Drug repurposing is an attractive strategy to control biofilm-related infectious diseases. In this study, two drugs (montelukast and cefoperazone) with well-established therapeutic applications were tested on Pseudomonas aeruginosa quorum sensing (QS) inhibition and biofilm control. METHODS AND RESULTS: The activity of montelukast and cefoperazone was evaluated for Pqs signal inhibition, pyocyanin synthesis, and prevention and eradication of Ps. aeruginosa biofilms. Cefoperazone inhibited the Pqs system by hindering the production of the autoinducer molecules 2-heptyl-4-hydroxyquinoline (HHQ) and 2-heptyl-3-hydroxy-4(1H)-quinolone (the Pseudomonas quinolone signal or PQS), corroborating in silico results. Pseudomonas aeruginosa pyocyanin production was reduced by 50%. The combination of the antibiotics cefoperazone and ciprofloxacin was synergistic for Ps. aeruginosa biofilm control. On the other hand, montelukast had no relevant effects on the inhibition of the Pqs system and against Ps. aeruginosa biofilm. CONCLUSION: This study provides for the first time strong evidence that cefoperazone interacts with the Pqs system, hindering the formation of the autoinducer molecules HHQ and PQS, reducing Ps. aeruginosa pathogenicity and virulence. Cefoperazone demonstrated a potential to be used in combination with less effective antibiotics (e.g. ciprofloxacin) to potentiate the biofilm control action.


Subject(s)
Acetates , Anti-Bacterial Agents , Biofilms , Cefoperazone , Cyclopropanes , Pseudomonas aeruginosa , Quinolines , Quorum Sensing , Sulfides , Pseudomonas aeruginosa/drug effects , Biofilms/drug effects , Sulfides/pharmacology , Quorum Sensing/drug effects , Anti-Bacterial Agents/pharmacology , Acetates/pharmacology , Quinolines/pharmacology , Cyclopropanes/pharmacology , Cefoperazone/pharmacology , Microbial Sensitivity Tests , Pyocyanine/metabolism , Ciprofloxacin/pharmacology , Quinolones/pharmacology
16.
Microb Pathog ; 191: 106663, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38679246

ABSTRACT

Quorum sensing (QS) has a central role in biofilm lifestyle and antimicrobial resistance, and disrupting these signaling pathways is a promising strategy to control bacterial pathogenicity and virulence. In this study, the efficacy of three structurally related benzaldehydes (4-hydroxybenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde (vanillin) and 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde)) in disrupting the las and pqs systems of Pseudomonas aeruginosa was investigated using bioreporter strains and computational simulations. Additionally, these benzaldehydes were combined with tobramycin and ciprofloxacin antibiotics to evaluate their ability to increase antibiotic efficacy in preventing and eradicating P. aeruginosa biofilms. To this end, the total biomass, metabolic activity and culturability of the biofilm cells were determined. In vitro assays results indicated that the aromatic aldehydes have potential to inhibit the las and pqs systems by > 80 %. Molecular docking studies supported these findings, revealing the aldehydes binding in the same pocket as the natural ligands or receptor proteins (LasR, PQSA, PQSE, PQSR). Benzaldehydes were shown to act as virulence factor attenuators, with vanillin achieving a 48 % reduction in pyocyanin production. The benzaldehyde-tobramycin combination led not only to a 60 % reduction in biomass production but also to a 90 % reduction in the metabolic activity of established biofilms. A similar result was observed when benzaldehydes were combined with ciprofloxacin. 4-Hydroxybenzaldehyde demonstrated relevant action in increasing biofilm susceptibility to ciprofloxacin, resulting in a 65 % reduction in biomass. This study discloses, for the first time, that the benzaldehydes studied are potent QS inhibitors and also enhancers of antibiotics antibiofilm activity against P. aeruginosa.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Benzaldehydes , Biofilms , Ciprofloxacin , Molecular Docking Simulation , Pseudomonas aeruginosa , Quorum Sensing , Tobramycin , Biofilms/drug effects , Quorum Sensing/drug effects , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Benzaldehydes/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Tobramycin/pharmacology , Ciprofloxacin/pharmacology , Bacterial Proteins/metabolism , Virulence Factors/metabolism , Microbial Sensitivity Tests , Drug Synergism , Pyocyanine/metabolism , Trans-Activators/metabolism , Trans-Activators/antagonists & inhibitors
17.
Int J Mol Sci ; 25(6)2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38542189

ABSTRACT

The encapsulation of retinol within silica microparticles has emerged as a promising opportunity in the realm of cosmetic and pharmaceutical formulations, driven by the need to reinforce the photoprotection and oxidation stability of retinol. This work examines the process of encapsulating retinol into silica microparticles. The association efficiency, microparticle size, molecular structure, morphology, oxidation, and release profile, as well as biocompatibility and skin sensitization, were evaluated. Results showed that 0.03% of retinol and 9% of emulsifier leads to an association efficiency higher than 99% and a particle size with an average of 5.2 µm. FTIR results indicate that there is an association of retinol with the silica microparticles, and some may be on the surface. Microscopy indicates that when association happens, there is less aggregation of the particles. Oxidation occurs in two different phases, the first related to the retinol on the surface and the second to the associated retinol. In addition, a burst release of up to 3 h (30% free retinol, 17% associated retinol) was observed, as well as a sustained release of 44% of retinol up to 24 h. Encapsulation allowed an increase in the minimal skin cytotoxic concentrations of retinol from 0.04 µg/mL to 1.25 mg/mL without skin sensitization. Overall, retinol is protected when associated with silica microparticles, being safe to use in cosmetics and dermatology.


Subject(s)
Retinoids , Saccharum , Delayed-Action Preparations , Vitamin A , Silicon Dioxide/chemistry , Particle Size
18.
J Biomol Struct Dyn ; : 1-10, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38529903

ABSTRACT

Complement C5 is the target of the monoclonal antibody eculizumab, used in complement dysregulating disorders, like the rare disease Paroxysmal Nocturnal Hemoglobinuria (PNH). PNH is an acquired hematopoietic stem cell condition characterized by aberrant destruction of erythrocytes, chronic hemolytic anemia, and thromboembolism propensity. C5 is a protein component of the complement system which is part of the immune system of the body and plays a prominent role in the destruction of red blood cells, misidentifying them as a threat. This work describes the application of molecular dynamics simulations to the study of the underlying interactions between complement C5 and eculizumab. This study also reveals the importance of single nucleotide polymorphisms on C5 protein concerning the effective inhibition of the mAB, involving the mechanistic events taking place at the interface spots of the complex. The predicted conformational change in the C5 Arg885/His/Cys mutation has implications on the protein's interaction with eculizumab, compromising their compatibility. The acquired insights into the conformational changes, dynamics, flexibility, and interactions shed light on the knowledge of the function of this biomolecule providing answers about the poor response to the treatment in PNH patient carriers of the mutations. By investigating the intricate dynamics, significant connections between C5 and eculizumab can be uncovered. Such insights may aid in the creation of novel compounds or lead to the enhancement of eculizumab's efficacy.Communicated by Ramaswamy H. Sarma.

19.
Mol Biol Evol ; 41(2)2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38314876

ABSTRACT

Substitution models of evolution are necessary for diverse evolutionary analyses including phylogenetic tree and ancestral sequence reconstructions. At the protein level, empirical substitution models are traditionally used due to their simplicity, but they ignore the variability of substitution patterns among protein sites. Next, in order to improve the realism of the modeling of protein evolution, a series of structurally constrained substitution models were presented, but still they usually ignore constraints on the protein activity. Here, we present a substitution model of protein evolution with selection on both protein structure and enzymatic activity, and that can be applied to phylogenetics. In particular, the model considers the binding affinity of the enzyme-substrate complex as well as structural constraints that include the flexibility of structural flaps, hydrogen bonds, amino acids backbone radius of gyration, and solvent-accessible surface area that are quantified through molecular dynamics simulations. We applied the model to the HIV-1 protease and evaluated it by phylogenetic likelihood in comparison with the best-fitting empirical substitution model and a structurally constrained substitution model that ignores the enzymatic activity. We found that accounting for selection on the protein activity improves the fitting of the modeled functional regions with the real observations, especially in data with high molecular identity, which recommends considering constraints on the protein activity in the development of substitution models of evolution.


Subject(s)
Amino Acids , Evolution, Molecular , Phylogeny , Probability , Models, Genetic , Amino Acid Substitution
20.
Food Funct ; 15(5): 2773, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38385976

ABSTRACT

Correction for 'Exploiting Locusta migratoria as a source of bioactive peptides with anti-fibrosis properties using an in silico approach' by Carla S. S. Teixeira et al., Food Funct., 2024, 15, 493-502, https://doi.org/10.1039/D3FO04246D.

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