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Frontiers in Immunology 2024Autoantigen-specific immunotherapy using peptides offers a more targeted approach to treat autoimmune diseases, but clinical implementation has been challenging. We...
Autoantigen-specific immunotherapy using peptides offers a more targeted approach to treat autoimmune diseases, but clinical implementation has been challenging. We previously showed that multivalent delivery of peptides as soluble antigen arrays (SAgAs) efficiently protects against spontaneous autoimmune diabetes in the non-obese diabetic (NOD) mouse model. Here, we compared the efficacy, safety, and mechanisms of action of SAgAs versus free peptides. SAgAs, but not their corresponding free peptides at equivalent doses, efficiently prevented the development of diabetes. SAgAs increased the frequency of regulatory T cells among peptide-specific T cells or induce their anergy/exhaustion or deletion, depending on the type of SAgA used (hydrolysable (hSAgA) and non-hydrolysable 'click' SAgA (cSAgA)) and duration of treatment, whereas their corresponding free peptides induced a more effector phenotype following delayed clonal expansion. Over time, the peptides induced an IgE-independent anaphylactic reaction, the incidence of which was significantly delayed when peptides were in SAgA form rather than in free form. Moreover, the N-terminal modification of peptides with aminooxy or alkyne linkers, which was needed for grafting onto hyaluronic acid to make hSAgA or cSAgA variants, respectively, influenced their stimulatory potency and safety, with alkyne-functionalized peptides being more potent and less anaphylactogenic than aminooxy-functionalized peptides. Immunologic anaphylaxis occurred in NOD mice in a dose-dependent manner but not in C57BL/6 or BALB/c mice; however, its incidence did not correlate with the level of anti-peptide antibodies. We provide evidence that SAgAs significantly improve the efficacy of peptides to induce tolerance and prevent autoimmune diabetes while at the same time reducing their anaphylactogenic potential.
Topics: Animals; Mice; Mice, Inbred NOD; Diabetes Mellitus, Type 1; Immune Tolerance; Peptides; Female; Autoantigens; T-Lymphocytes, Regulatory; Immunotherapy; Anaphylaxis; Desensitization, Immunologic
PubMed: 38933266
DOI: 10.3389/fimmu.2024.1258369 -
Sensors (Basel, Switzerland) Jun 2024To monitor the biological function of HS in real time, this investigation demonstrated the design and synthesis of a novel fluorescent probe integrated with cyanine and...
To monitor the biological function of HS in real time, this investigation demonstrated the design and synthesis of a novel fluorescent probe integrated with cyanine and 2,4-dinitrophenol for the qualitative and quantitative detection of HS. An NIR sensitive sensor (FS-HS-1) was provided with a straightforward process. Spectroscopy experiments elucidated that FS-HS-1 could selectively detect HS in a PBS solution (containing 40% acetonitrile) with a 111-fold fluorescence enhancement at 715 nm (ex. 605 nm). The response towards NaHS occurred in less than 2 min, and the detection limit was confirmed to be as low as 4.47 ± 0.11 nmol/L. Furthermore, the probe is capable of monitoring changes in exogenous HS concentrations within living cells with confocal and 2P imaging.
Topics: Hydrogen Sulfide; Humans; Fluorescent Dyes; Carbocyanines; Spectroscopy, Near-Infrared; HeLa Cells; Limit of Detection; 2,4-Dinitrophenol
PubMed: 38931528
DOI: 10.3390/s24123744 -
Pharmaceuticals (Basel, Switzerland) Jun 2024Polymersomes, self-assembled nanoparticles composed of amphiphilic block copolymers, have emerged as promising versatile nanovesicles with various applications, such as... (Review)
Review
Polymersomes, self-assembled nanoparticles composed of amphiphilic block copolymers, have emerged as promising versatile nanovesicles with various applications, such as drug delivery, medical imaging, and diagnostics. The integration of click chemistry reactions, specifically the copper [I]-catalysed azide-alkyne cycloaddition (CuAAC), has greatly expanded the functionalisation and bioconjugation capabilities of polymersomes and new drugs, being this synergistic combination explored in this review. It also provides up-to-date examples of previous incorporations of click-compatible moieties (azide and alkyne functional groups) into polymer building blocks, enabling the "click" attachment of various functional groups and ligands, delving into the diverse range of click reactions that have been reported and employed for polymersome copolymer synthesis and the modification of polymersome surfaces, including ligand conjugation and surface modification. Overall, this review explores the current state-of-the-art of the combinatory usage, in recent years, of polymersomes with the click chemistry reaction, highlighting examples of studies of their synthesis and functionalisation strategies.
PubMed: 38931414
DOI: 10.3390/ph17060747 -
Molecules (Basel, Switzerland) Jun 2024Since the discovery of metal-catalyzed azide-alkyne cycloadditions, 1,2,3-triazoles have been widely used as linkers for various residues. 1,2,3-Triazole is an aromatic...
Since the discovery of metal-catalyzed azide-alkyne cycloadditions, 1,2,3-triazoles have been widely used as linkers for various residues. 1,2,3-Triazole is an aromatic five-membered cyclic compound consisting of three nitrogen and two carbon atoms with large dipoles that absorb UV light. In the past decade, we have been working on the synthesis of dense triazole polymers possessing many 1,2,3-triazole residues linked through a carbon atom in their backbone as a new type of functional polymer. Recently, we reported that stereoregular dense triazole uniform oligomers exhibit a circular dichroism signal based on the chiral arrangement of two neighboring 1,2,3-triazole residues. In this study, to investigate the chiral conformation of two neighboring 1,2,3-triazole residues in stereoregular dense triazole uniform oligomers, density functional theory (DFT) calculations were performed using 1,2,3-triazole diads with different substitution positions and conformations as model compounds and compared with our previous results.
PubMed: 38930995
DOI: 10.3390/molecules29122931 -
International Journal of Molecular... Jun 2024Inhibitors of monoamine oxidases (MAOs) are of interest for the treatment of neurodegenerative disorders and other human pathologies. In this frame, the present work...
Synthesis, Molecular Electron Density Theory Study, Molecular Docking, and Pharmacological Evaluation of New Coumarin-Sulfonamide-Nitroindazolyl-Triazole Hybrids as Monoamine Oxidase Inhibitors.
Inhibitors of monoamine oxidases (MAOs) are of interest for the treatment of neurodegenerative disorders and other human pathologies. In this frame, the present work describes different synthetic strategies to obtain MAO inhibitors via the coupling of the aminocoumarin core with arylsulfonyl chlorides followed by copper azide-alkyne cycloaddition, leading to coumarin-sulfonamide-nitroindazolyl-triazole hybrids. The nitration position on the coumarin moiety was confirmed through nuclear magnetic resonance spectroscopy and molecular electron density theory in order to elucidate the molecular mechanism and selectivity of the electrophilic aromatic substitution reaction. The coumarin derivatives were evaluated for their inhibitory potency against monoamine oxidases and cholinesterases. Molecular docking calculations provided a rational binding mode of the best compounds in the series with MAO A and B. The work identified hybrids - as novel MAO inhibitors, with a selective action against isoform B, of potential interest to combat neurological diseases.
Topics: Molecular Docking Simulation; Coumarins; Monoamine Oxidase Inhibitors; Triazoles; Monoamine Oxidase; Humans; Sulfonamides; Structure-Activity Relationship; Molecular Structure; Density Functional Theory
PubMed: 38928509
DOI: 10.3390/ijms25126803 -
Toxins Jun 2024Physiologically based pharmacokinetic (PBPK) models were utilized to investigate potential interactions between aflatoxin B1 (AFB1) and efavirenz (EFV), a non-nucleoside...
Physiologically based pharmacokinetic (PBPK) models were utilized to investigate potential interactions between aflatoxin B1 (AFB1) and efavirenz (EFV), a non-nucleoside reverse transcriptase inhibitor drug and inducer of several CYP enzymes, including CYP3A4. PBPK simulations were conducted in a North European Caucasian and Black South African population, considering different dosing scenarios. The simulations predicted the impact of EFV on AFB1 metabolism via CYP3A4 and CYP1A2. In vitro experiments using human liver microsomes (HLM) were performed to verify the PBPK predictions for both single- and multiple-dose exposures to EFV. Results showed no significant difference in the formation of AFB1 metabolites when combined with EFV (0.15 µM) compared to AFB1 alone. However, exposure to 5 µM of EFV, mimicking chronic exposure, resulted in increased CYP3A4 activity, affecting metabolite formation. While co-incubation with EFV reduced the formation of certain AFB1 metabolites, other outcomes varied and could not be fully attributed to CYP3A4 induction. Overall, this study provides evidence that EFV, and potentially other CYP1A2/CYP3A4 perpetrators, can impact AFB1 metabolism, leading to altered exposure to toxic metabolites. The results emphasize the importance of considering drug interactions when assessing the risks associated with mycotoxin exposure in individuals undergoing HIV therapy in a European and African context.
Topics: Aflatoxin B1; Humans; Benzoxazines; Alkynes; Cyclopropanes; Microsomes, Liver; Drug Interactions; Models, Biological; Reverse Transcriptase Inhibitors; Male; Cytochrome P-450 CYP3A; Adult; Female; Cytochrome P-450 CYP1A2; Middle Aged; Young Adult; White People
PubMed: 38922153
DOI: 10.3390/toxins16060259 -
Beilstein Journal of Organic Chemistry 2024A synthesis route to access triazole-pyrazole hybrids via triazenylpyrazoles was developed. Contrary to existing methods, this route allows the facile -functionalization...
A synthesis route to access triazole-pyrazole hybrids via triazenylpyrazoles was developed. Contrary to existing methods, this route allows the facile -functionalization of the pyrazole before the attachment of the triazole unit via a copper-catalyzed azide-alkyne cycloaddition. The developed methodology was used to synthesize a library of over fifty new multi-substituted pyrazole-triazole hybrids. We also demonstrate a one-pot strategy that renders the isolation of potentially hazardous azides obsolete. In addition, the compatibility of the method with solid-phase synthesis is shown exemplarily.
PubMed: 38919604
DOI: 10.3762/bjoc.20.121 -
Nature Communications Jun 2024In general, the P-centered ring-opening of quaternary phosphirenium salts (QPrS) predominantly leads to hydrophosphorylated products, while the C-centered ring-opening...
In general, the P-centered ring-opening of quaternary phosphirenium salts (QPrS) predominantly leads to hydrophosphorylated products, while the C-centered ring-opening is primarily confined to intramolecular nucleophilic reactions, resulting in the formation of phosphorus-containing cyclization products instead of difunctionalized products generated through intermolecular nucleophilic processes. Here, through the promotion of ring-opening of three-member rings by iodine anions and the quenching of electronegative carbon atoms by iodine cations, we successfully synthesize β-functionalized vinylphosphine oxides by the P-addition of QPrS intermediates generated in situ. Multiple β-iodo-substituted vinylphosphine oxides can be obtained with exceptional regio- and stereo-selectivity by reacting secondary phosphine oxides with unactivated alkynes. In addition, a variety of β-functionalized vinylphosphine oxides converted from C-I bonds, especially the rapid construction of benzo[b]phospholes oxides, demonstrates the significance of this strategy.
PubMed: 38918418
DOI: 10.1038/s41467-024-49640-z -
BMC Oral Health Jun 2024Dental pathogens play a crucial role in oral health issues, including tooth decay, gum disease, and oral infections, and recent research suggests a link between these...
BACKGROUND
Dental pathogens play a crucial role in oral health issues, including tooth decay, gum disease, and oral infections, and recent research suggests a link between these pathogens and oral cancer initiation and progression. Innovative therapeutic approaches are needed due to antibiotic resistance concerns and treatment limitations.
METHODS
We synthesized and analyzed piperine-coated zinc oxide nanoparticles (ZnO-PIP NPs) using UV spectroscopy, SEM, XRD, FTIR, and EDAX. Antioxidant and antimicrobial effectiveness were evaluated through DPPH, ABTS, and MIC assays, while the anticancer properties were assessed on KB oral squamous carcinoma cells.
RESULTS
ZnO-PIP NPs exhibited significant antioxidant activity and a MIC of 50 µg/mL against dental pathogens, indicating strong antimicrobial properties. Interaction analysis revealed high binding affinity with dental pathogens. ZnO-PIP NPs showed dose-dependent anticancer activity on KB cells, upregulating apoptotic genes BCL2, BAX, and P53.
CONCLUSIONS
This approach offers a multifaceted solution to combatting both oral infections and cancer, showcasing their potential for significant advancement in oral healthcare. It is essential to acknowledge potential limitations and challenges associated with the use of ZnO NPs in clinical applications. These may include concerns regarding nanoparticle toxicity, biocompatibility, and long-term safety. Further research and rigorous testing are warranted to address these issues and ensure the safe and effective translation of ZnO-PIP NPs into clinical practice.
Topics: Zinc Oxide; Humans; Piperidines; Apoptosis; Alkaloids; Benzodioxoles; Mouth Neoplasms; bcl-2-Associated X Protein; Proto-Oncogene Proteins c-bcl-2; Tumor Suppressor Protein p53; Biofilms; Polyunsaturated Alkamides; Nanoparticles; Antioxidants; Microbial Sensitivity Tests; Metal Nanoparticles; Antineoplastic Agents; Microscopy, Electron, Scanning; X-Ray Diffraction; Cell Line, Tumor; KB Cells
PubMed: 38907185
DOI: 10.1186/s12903-024-04399-z -
Biochimica Et Biophysica Acta.... Jun 2024Ubiquinone (UQ) is an essential player in the respiratory electron transfer system. In Saccharomyces cerevisiae strains lacking the ability to synthesize UQ, exogenously...
Ubiquinone (UQ) is an essential player in the respiratory electron transfer system. In Saccharomyces cerevisiae strains lacking the ability to synthesize UQ, exogenously supplied UQs can be taken up and delivered to mitochondria through an unknown mechanism, restoring the growth of UQ-deficient yeast in non-fermentable medium. Since elucidating the mechanism responsible may markedly contribute to therapeutic strategies for patients with UQ deficiency, many attempts have been made to identify the machinery involved in UQ trafficking in the yeast model. However, definite experimental evidence of the direct interaction of UQ with a specific protein(s) has not yet been demonstrated. To gain insight into intracellular UQ trafficking via a chemistry-based strategy, we synthesized a hydrophobic UQ probe (pUQ5), which has a photoreactive diazirine group attached to a five-unit isoprenyl chain and a terminal alkyne to visualize and/or capture the labeled proteins via click chemistry. pUQ5 successfully restored the growth of UQ-deficient S. cerevisiae (Δcoq2) on a non-fermentable carbon source, indicating that this UQ was taken up and delivered to mitochondria, and served as a UQ substrate of respiratory enzymes. Through photoaffinity labeling of the mitochondria isolated from Δcoq2 yeast cells cultured in the presence of pUQ5, we identified many labeled proteins, including voltage-dependent anion channel 1 (VDAC1) and cytochrome c oxidase subunit 3 (Cox3). The physiological relevance of UQ binding to these proteins is discussed.
PubMed: 38906315
DOI: 10.1016/j.bbabio.2024.149147