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1.
Colloids Surf B Biointerfaces ; 238: 113921, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38631280

RESUMO

Tumor microenvironment (TME)-responsive size-changeable and biodegradable nanoplatforms for multimodal therapy possess huge advantages in anti-tumor therapy. Hence, we developed a hyaluronic acid (HA) modified CuS/MnO2 nanosheets (HCMNs) as a multifunctional nanoplatform for synergistic chemodynamic therapy (CDT)/photothermal therapy (PTT)/photodynamic therapy (PDT). The prepared HCMNs exhibited significant NIR light absorption and photothermal conversion efficiency because of the densely deposited ultra-small sized CuS nanoparticles on the surface of MnO2 nanosheet. They could precisely target the tumor cells and rapidly decomposed into small sized nanostructures in the TME, and then efficiently promote intracellular ROS generation through a series of cascade reactions. Moreover, the local temperature elevation induced by photothermal effect also promote the PDT based on CuS nanoparticles and the Fenton-like reaction of Mn2+, thereby enhancing the therapeutic efficiency. Furthermore, the T1-weighted magnetic resonance (MR) imaging was significantly enhanced by the abundant Mn2+ ions from the decomposition process of HCMNs. In addition, the CDT/PTT/PDT synergistic therapy using a single NIR light source exhibited considerable anti-tumor effect via in vitro cell test. Therefore, the developed HCMNs will provide great potential for MR imaging and multimodal synergistic cancer therapy.


Assuntos
Cobre , Ácido Hialurônico , Imageamento por Ressonância Magnética , Compostos de Manganês , Óxidos , Fotoquimioterapia , Microambiente Tumoral , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Óxidos/química , Óxidos/farmacologia , Humanos , Cobre/química , Cobre/farmacologia , Tamanho da Partícula , Nanoestruturas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Fototerapia , Nanopartículas/química , Sobrevivência Celular/efeitos dos fármacos , Propriedades de Superfície , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Animais
2.
Food Chem ; 448: 139127, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608399

RESUMO

To address the food safety issues caused by toxins, we established a fluorescent copper nanocluster biosensor based on magnetic aptamer for the visual and quantitative detection of ZEN. Specifically, we utilized the docking-aided rational tailoring (DART) strategy to analyze intermolecular force and interaction sites between zearalenone (ZEN) and the aptamer, and optimize the long-chain aptamer step by step to enhance the binding affinity by 3.4 times. The magnetic bead-modified aptamer underwent conformational changes when competing with complementary sequences to bind with ZEN. Then, the released complementary sequences will be amplified in template-free mode with the presence of the terminal deoxynucleotidyl transferase (TdT), and generating T-rich sequences as the core sequences for the luminescence of copper nanoclusters. The luminescence could be visualized and quantitatively detected through ultraviolet irradiation. The proposed label-free aptasensor exhibited high sensitivity and specificity, with a low limit of detection (LOD) of 0.1 ng/mL.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Cobre , Zearalenona , Zearalenona/análise , Zearalenona/química , Cobre/química , Técnicas Biossensoriais/instrumentação , Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise , Limite de Detecção , Simulação de Acoplamento Molecular , Nanopartículas Metálicas/química , Fluorescência
3.
J Colloid Interface Sci ; 666: 434-446, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608638

RESUMO

Bacterial infections are among the most significant causes of death in humans. Chronic misuse or uncontrolled use of antibiotics promotes the emergence of multidrug-resistant superbugs that threaten public health through the food chain and cause environmental pollution. Based on the above considerations, copper selenide nanosheets (CuSe NSs) with photothermal therapy (PTT)- and photodynamic therapy (PDT)-related properties have been fabricated. These CuSe NSs possess enhanced PDT-related properties and can convert O2 into highly toxic reactive oxygen species (ROS), which can cause significant oxidative stress and damage to bacteria. In addition, CuSe NSs can efficiently consume glutathione (GSH) at bacterial infection sites, thus further enhancing their sterilization efficacy. In vitro antibacterial experiments with near-infrared (NIR) irradiation have shown that CuSe NSs have excellent photothermal bactericidal properties. These experiments also showed that CuSe NSs exerted excellent bactericidal effects on wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) and significantly promoted the healing of infected wounds. Because of their superior biological safety, CuSe NSs are novel copper-based antimicrobial agents that are expected to enter clinical trials, serving as a modern approach to the major problem of treating bacterially infected wounds.


Assuntos
Antibacterianos , Cobre , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Nanoestruturas , Terapia Fototérmica , Cobre/química , Cobre/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Nanoestruturas/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Humanos , Propriedades de Superfície , Tamanho da Partícula , Selênio/química , Selênio/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico
4.
Environ Sci Pollut Res Int ; 31(20): 29264-29279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573576

RESUMO

Guided by efficient utilization of natural plant oil and sulfur as low-cost sorbents, it is desired to tailor the porosity and composition of polysulfides to achieve their optimal applications in the management of aquatic heavy metal pollution. In this study, polysulfides derived from soybean oil and sulfur (PSSs) with improved porosity (10.2-22.9 m2/g) and surface oxygen content (3.1-7.0 wt.%) were prepared with respect to reaction time of 60 min, reaction temperature of 170 °C, and mass ratios of sulfur/soybean oil/NaCl/sodium citrate of 1:1:3:2. The sorption behaviors of PSSs under various hydrochemical conditions such as contact time, pH, ionic strength, coexisting cations and anions, temperature were systematically investigated. PSSs presented a fast sorption kinetic (5.0 h) and obviously improved maximum sorption capacities for Pb(II) (180.5 mg/g), Cu(II) (49.4 mg/g), and Cr(III) (37.0 mg/g) at pH 5.0 and T 298 K, in comparison with polymers made without NaCl/sodium citrate. This study provided a valuable reference for the facile preparation of functional polysulfides as well as a meaningful option for the removal of aquatic heavy metals.


Assuntos
Cobre , Chumbo , Metais Pesados , Óleo de Soja , Sulfetos , Poluentes Químicos da Água , Adsorção , Chumbo/química , Óleo de Soja/química , Cobre/química , Sulfetos/química , Porosidade , Poluentes Químicos da Água/química , Metais Pesados/química , Cromo/química , Cinética , Concentração de Íons de Hidrogênio
5.
Langmuir ; 40(11): 5738-5752, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38450610

RESUMO

The pumpkin leaf was extracted by the decoction method, and it was used as an eco-friendly, nontoxic inhibitor of copper in 0.5 M H2SO4 corrosion media. To evaluate the composition and protective capacity of the pumpkin leaf extract, Fourier infrared spectroscopy, electrochemical testing, XPS, AFM, and SEM were employed. The results showed that the pumpkin leaf extract (PLE) is an effective cathode corrosion inhibitor, exhibiting exceptional protection for copper within a specific temperature range. The corrosion inhibition efficiency of the PLE against copper reached 89.98% when the concentration of the PLE reached 800 mg/L. Furthermore, when the temperature and soaking time increased, the corrosion protection efficiency of 800 mg/L PLE on copper consistently remained above 85%. Analysis of the morphology also indicated that the PLE possesses equally effective protection for copper at different temperatures. Furthermore, XPS analysis reveals that the PLE molecules are indeed adsorbed to form an adsorption film, which is consistent with Langmuir monolayer adsorption. Molecular dynamics simulations and quantum chemical calculations were conducted on the main components of the PLE.


Assuntos
Cucurbita , Corrosão , Cobre/química , Aço/química , Extratos Vegetais/química
6.
Sci Rep ; 14(1): 5589, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453990

RESUMO

The utilization of plants for the production of metallic nanoparticles is gaining significant attention in research. In this study, we conducted phytochemical screening of Alstonia scholaris (A. scholaris) leaves extracts using various solvents, including chloroform, ethyl acetate, n-hexane, methanol, and water. Our findings revealed higher proportions of flavonoids and alkaloids in both solvents compared to other phytochemical species. In the methanol, extract proteins, anthraquinone and reducing sugar were not detected. On the other hand, the aqueous extract demonstrated the presence of amino acids, reducing sugar, phenolic compounds, anthraquinone, and saponins. Notably, ethyl acetate and chloroform extracts displayed the highest levels of bioactive compounds among all solvents. Intrigued by these results, we proceeded to investigate the antibacterial properties of the leaf extracts against two major bacterial strains, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). All extracts exhibited significant zones of inhibition against both bacterial isolates, with S. aureus showing higher susceptibility compared to E. coli. Notably, the methanol extract displayed the most potent I hibitory effect against all organisms. Inspired by the bioactivity of the methanol extract, we employed it as a plant-based material for the green synthesis of copper nanoparticles (Cu-NPs). The synthesized Cu-NPs were characterized using Fourier infrared spectroscopy (FT-IR), UV-visible spectroscopic analysis, and scanning electron microscopy (SEM). The observed color changes confirmed the successful formation of Cu-NPs, while the FTIR analysis matched previously reported peaks, further verifying the synthesis. The SEM micrographs indicated the irregular shapes of the surface particles. From the result obtained by energy dispersive X-ray spectroscopic analysis, Cu has the highest relative abundance of 67.41 wt%. Confirming the purity of the Cu-NPs colloid. These findings contribute to the growing field of eco-friendly nanotechnology and emphasize the significance of plant-mediated approaches in nanomaterial synthesis and biomedical applications.


Assuntos
Acetatos , Alstonia , Anti-Infecciosos , Nanopartículas Metálicas , Cobre/química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Escherichia coli , Metanol/farmacologia , Clorofórmio/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Antibacterianos/química , Nanopartículas Metálicas/química , Compostos Fitoquímicos/farmacologia , Solventes/farmacologia , Açúcares/farmacologia , Antraquinonas/farmacologia , Testes de Sensibilidade Microbiana
7.
Colloids Surf B Biointerfaces ; 237: 113861, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552288

RESUMO

Copper and copper oxide nanoparticles (CuNPs) have unique physicochemical properties that make them highly promising for biomedical applications. This review discusses the application of CuNPs in biomedicine, including diagnosis, therapy, and theranostics. Recent synthesis methods, with an emphasis on green approaches, are described, and the latest techniques for nanoparticle characterization are critically analyzed. CuNPs, including Cu2O, CuO, and Cu, have significant potential as anti-cancer agents, drug delivery systems, and photodynamic therapy enhancers, among other applications. While challenges such as ensuring biocompatibility and stability must be addressed, the state-of-the-art research reviewed here provides strong evidence for the efficacy and versatility of CuNPs. These multifunctional properties have been extensively researched and documented, showcasing the immense potential of CuNPs in biomedicine. Overall, the evidence suggests that CuNPs are a promising avenue for future research and development in biomedicine. We strongly support further progress in the development of synthesis and application strategies to enhance the effectiveness and safety of CuNPs for clinical purposes.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Cobre/química , Nanopartículas Metálicas/química , Nanopartículas/química , Antioxidantes/química , Extratos Vegetais/química
8.
Environ Sci Pollut Res Int ; 31(18): 26916-26927, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456980

RESUMO

Catalytic wet peroxide oxidation (CWPO) has become an important deep oxidation technology for organics removal in wastewater treatments. Supported Cu-based catalysts belong to an important type of CWPO catalyst. In this paper, two Cu catalysts, namely, Cu/Al2O3-air and Cu/Al2O3-H2 were prepared and evaluated through catalytic degradation of phenol. It was found that Cu/Al2O3-H2 had an excellent catalytic performance (TOC removal rate reaching 96%) and less metal dissolution than the Cu/Al2O3-air case. Moreover, when the organic removal rate was promoted at a higher temperature, the metal dissolution amounts was decreased. Combined with hydroxyl radical quenching experiments, a catalytic oxidation mechanism was proposed to explain the above-mentioned interesting behaviors of the Cu/Al2O3-H2 catalyst for CWPO. The catalytic test results as well as the proposed mechanism can provide better guide for design and synthesis of good CWPO catalysts.


Assuntos
Cobre , Oxirredução , Peróxidos , Fenol , Catálise , Cobre/química , Peróxidos/química , Fenol/química , Óxido de Alumínio/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos
9.
Sci Total Environ ; 919: 170752, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340864

RESUMO

Elucidating whether dissolved Cu uptake is kinetically or thermodynamically controlled, and the effects of speciation on Cu transport by phytoplankton will allow better modeling of the fate and impact of dissolved Cu in the ocean. To address these questions, we performed Cu physiological and physicochemical experiments using the model diatom, Phaeodactylum tricornutum, grown in natural North Atlantic seawater (0.44 nM Cu). Using competitive ligand equilibration-cathodic stripping voltammetry (CLE-CSV), we measured two organic ligand types released by P. tricornutum to bind Cu (L1 and L2) at concentrations of ~0.35 nM L1 and 1.3 nM L2. We also established the presence of two putative Cu-binding sites at the cell surface of P. tricornutum (S1 and S2) with log K differing by ~5 orders of magnitude (i.e., 12.9 vs. 8.1) and cell surface densities by 9-fold. Only the high-affinity binding sites, S1, exhibit reductase activity. Using voltammetric kinetic measurements and a theoretical kinetic model, we calculated the forward and dissociation rate constants of L1 and S1. Complementary 67Cu uptake experiments identified a high- and a low-affinity Cu uptake system in P. tricornutum, with half-saturation constant (Km) of 154 nM and 2.63 µM dissolved Cu, respectively. In the P. tricornutum genome, we identified a putative high-affinity Cu transporter (PtCTR49224) and a putative ZIP-like, low-affinity Cu transporter (PtZIP49400). PtCTR49224 has high homology to Homo sapiens hCTR1, which depending on the accessibility to extracellular reducing agents, the hCTR1 itself is involved in the reduction of Cu2+ to Cu+ before internalization. We combined these physiological and physicochemical data to calculate the rate constants for the internalization of Cu, and established that while the high-affinity Cu uptake system (S1) is borderline between a kinetically or thermodynamically controlled system, the low-affinity Cu transporters, S2, is thermodynamically-controlled. We revised the inverse relationship between the concentrations of inorganic complexes of essential metals (i.e., Ni, Fe, Co, Zn, Cd, Mn and Cu) in the mixed layer and the formation rate constant of metal transporters in phytoplankton, highlighting the link between the chemical properties of phytoplankton metal transporters and the availability and speciation of trace metals in the surface ocean.


Assuntos
Diatomáceas , Oligoelementos , Humanos , Diatomáceas/fisiologia , Ligantes , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/farmacologia , Metais/metabolismo , Oceanos e Mares , Fitoplâncton/metabolismo , Oligoelementos/metabolismo , Cobre/química
10.
Int J Biol Macromol ; 260(Pt 2): 129275, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242408

RESUMO

Adsorption-based treatment of sulfate contaminated water sources present challenges due to its favourable hydration characteristics. Herein, a copper-modified granular chitosan-based biocomposite (CHP-Cu) was prepared and characterized for its sulfate adsorption properties at neutral pH via batch equilibrium and fixed-bed column studies. The CHP-Cu adsorbent was characterized by complementary methods: spectroscopy (IR, Raman, X-ray photoelectron), thermal gravimetry analysis (TGA) and pH-based surface charge analysis. Sulfate adsorption at pH 7.2 with CHP-Cu follows the Sips isotherm model with a maximum adsorption capacity (407 mg/g) that exceeds most reported values of granular biosorbents at similar conditions. For the dynamic adsorption study, initial sulfate concentration, bed height, and flow rate were influential parameters governing sulfate adsorption. The Thomas and Yoon-Nelson models yield a sulfate adsorption capacity (146 mg/g) for the fixed bed system at optimized conditions. CHP-Cu was regenerated over 5 cycles (33 % to 31 %) with negligible Cu-leaching. The adsorbent also displays excellent sulfate uptake properties, regenerability, and sustainable adsorbent properties for effective point-of-use sulfate remediation in aqueous media near neutral pH (7.2). This sulfate remediation strategy is proposed for other oxyanion systems relevant to contaminated environmental surface and groundwater resources.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Cobre/química , Sulfatos , Poluentes Químicos da Água/química , Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética
11.
J Nanobiotechnology ; 22(1): 28, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216982

RESUMO

Incorporating green chemistry concepts into nanotechnology is an important focus area in nanoscience. The demand for green metal oxide nanoparticle production has grown in recent years. The beneficial effects of using nanoparticles in agriculture have already been established. Here, we highlight some potential antifungal properties of Zizyphus spina leaf extract-derived copper oxide nanoparticles (CuO-Zs-NPs), produced with a spherical shape and defined a 13-30 nm particle size. Three different dosages of CuO-Zs-NPs were utilized and showed promising antifungal efficacy in vitro and in vivo against the selected fungal strain of F. solani causes tomato root rot disease, which was molecularly identified with accession number (OP824846). In vivo  results indicated that, for all CuO-Zs-NPs concentrations, a significant reduction in Fusarium root rot disease occurred between 72.0 to 88.6% compared to 80.5% disease severity in the infected control. Although treatments with either the chemical fungicide (Kocide 2000) showed a better disease reduction and incidence with (18.33% and 6.67%) values, respectively, than CuO-Zs-NPs at conc. 50 mg/l, however CuO-Zs-NPs at 250 mg/l conc. showed the highest disease reduction (9.17 ± 2.89%) and lowest disease incidence (4.17 ± 3.80%). On the other hand, CuO-Zs-NPs at varied values elevated the beneficial effects of tomato seedling vigor at the initial stages and plant growth development compared to either treatment with the commercial fungicide or Trichoderma Biocide. Additionally, CuO-Zs-NPs treatments introduced beneficial results for tomato seedling development, with a significant increase in chlorophyll pigments and enzymatic activity for CuO-Zs-NPs treatments. Additionally, treatment with low concentrations of CuO-Zs-NPs led to a rise in the number of mature pollen grains compared to the immature ones.  however the data showed that CuO-Zs-NPs have a unique antifungal mechanism against F. solani, they  subsequently imply that CuO-Zs-NPs might be a useful environmentally friendly controlling agent for the Fusarium root rot disease that affects tomato plants.


Assuntos
Fungicidas Industriais , Fusarium , Nanopartículas Metálicas , Nanopartículas , Solanum lycopersicum , Ziziphus , Cobre/farmacologia , Cobre/química , Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Nanopartículas Metálicas/química , Óxidos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química
12.
Inorg Chem ; 63(5): 2340-2351, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38243896

RESUMO

In the context of Alzheimer's disease, copper (Cu) can be loosely bound to the amyloid-ß (Aß) peptide, leading to the formation of CuAß, which can catalytically generate reactive oxygen species that contribute to oxidative stress. To fight against this phenomenon, the chelation therapy approach has been developed and consists of using a ligand able to remove Cu from Aß and to redox-silence it, thus stopping the reactive oxygen species (ROS) production. A large number of Cu(II) chelators has been studied, allowing us to define and refine the properties required to design a "good" ligand, but without strong therapeutic outcomes to date. Those chelators targeted the Cu(II) redox state. Herein, we explore a parallel and relevant alternative pathway by designing a chelator able to target the Cu(I) redox state. To that end, we designed LH2 ([1N3S] binding set) and demonstrated that (i) it is perfectly able to extract Cu(I) from Cu(I)Aß even in the presence of an excess of Zn(II) and (ii) it redox-silences the Cu, preventing the formation of ROS. We showed that LH2 that is sensitive to oxidation can efficiently replace the [Zn(II)L] complex without losing its excellent ability to stop the ROS production while increasing its resistance to oxidation.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ligantes , Peptídeos beta-Amiloides/química , Cobre/química , Quelantes/química
13.
Nat Commun ; 15(1): 460, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212655

RESUMO

Targeted assembly of nanoparticles in biological systems holds great promise for disease-specific imaging and therapy. However, the current manipulation of nanoparticle dynamics is primarily limited to organic pericyclic reactions, which necessitate the introduction of synthetic functional groups as bioorthogonal handles on the nanoparticles, leading to complex and laborious design processes. Here, we report the synthesis of tyrosine (Tyr)-modified peptides-capped iodine (I) doped CuS nanoparticles (CuS-I@P1 NPs) as self-catalytic building blocks that undergo self-propelled assembly inside tumour cells via Tyr-Tyr condensation reactions catalyzed by the nanoparticles themselves. Upon cellular internalization, the CuS-I@P1 NPs undergo furin-guided condensation reactions, leading to the formation of CuS-I nanoparticle assemblies through dityrosine bond. The tumour-specific furin-instructed intracellular assembly of CuS-I NPs exhibits activatable dual-modal imaging capability and enhanced photothermal effect, enabling highly efficient imaging and therapy of tumours. The robust nanoparticle self-catalysis-regulated in situ assembly, facilitated by natural handles, offers the advantages of convenient fabrication, high reaction specificity, and biocompatibility, representing a generalizable strategy for target-specific activatable biomedical imaging and therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Furina , Fototerapia , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Nanopartículas/química , Catálise , Cobre/química
14.
J Am Chem Soc ; 146(3): 2102-2112, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38225538

RESUMO

Recent therapeutic strategies suggest that small peptides can act as aggregation inhibitors of monomeric amyloid-ß (Αß) by inducing structural rearrangements upon complexation. However, characterizing the binding events in such dynamic and transient noncovalent complexes, especially in the presence of natively occurring metal ions, remains a challenge. Here, we deploy a combined transition metal ion Förster resonance energy transfer (tmFRET) and native ion mobility-mass spectrometry (IM-MS) approach to characterize the structure of mass- and charge-selected Aß complexes with Cu(II) ions (a quencher) and a potential aggregation inhibitor, a small neuropeptide named leucine enkephalin (LE). We show conformational changes of monomeric Αß species upon Cu(II)-binding, indicating an uncoiled N-terminus and a close interaction between the C-terminus and the central hydrophobic region. Furthermore, we introduce LE labeled at the N-terminus with a metal-chelating agent, nitrilotriacetic acid (NTA). This allows us to employ tmFRET to probe the binding even in low-abundance and transient Aß-inhibitor-metal ion complexes. Complementary intramolecular distance and global shape information from tmFRET and native IM-MS, respectively, confirmed Cu(II) displacement toward the N-terminus of Αß, which discloses the binding region and the inhibitor's orientation.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Elementos de Transição , Ligantes , Peptídeos beta-Amiloides/química , Metais/química , Íons , Cobre/química
15.
J Phys Chem B ; 128(4): 973-984, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38236012

RESUMO

Metalloproteins make up a class of proteins that incorporate metal ions into their structures, enabling them to perform essential functions in biological systems, such as catalysis and electron transport. Azurin is one such metalloprotein with copper cofactor, having a ß-barrel structure with exceptional thermal stability. The copper metal ion is coordinated at one end of the ß-barrel structure, and there is a disulfide bond at the opposite end. In this study, we explore the effect of this disulfide bond in the high thermal stability of azurin by analyzing both the native S-S bonded and S-S nonbonded (S-S open) forms using temperature replica exchange molecular dynamics (REMD). Similar to experimental observations, we find a 35 K decrease in denaturation temperature for S-S open azurin compared to that of the native holo form (420 K). As observed in the case of native holo azurin, the unfolding process of the S-S open form also started with disruptions of the α-helix. The free energy surfaces of the unfolding process revealed that the denaturation event of the S-S open form progresses through different sets of conformational ensembles. Subsequently, we compared the stabilities of individual ß-sheet strands of both the S-S bonded and the S-S nonbonded forms of azurin. Further, we examined the contacts between individual residues for the central structures from the free energy surfaces of the S-S nonbonded form. The microscopic origin of the lowering in the denaturation temperature is further supplemented by thermodynamic analysis.


Assuntos
Azurina , Metaloproteínas , Azurina/química , Cobre/química , Metaloproteínas/metabolismo , Dissulfetos/química , Temperatura , Íons , Dobramento de Proteína
16.
J Biomol Struct Dyn ; 42(3): 1145-1156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37066617

RESUMO

Two-dimensional (2D) nanomaterials can improve drug delivery by reducing toxicity, increasing bioavailability and boosting efficacy. In this study, the simultaneous use of transition metal carbides and nitrides (MXenes) along with copper (II) benzene-1, 3, 5-tricarboxylate metal-organic framework (Cu - BTC/MOF) as attractive nanocarriers are investigated for loading and delivering curcumin (CUR) and paclitaxel (PTX) drugs to cancer cells. The efficiency of surface termination (bare and oxygen) in the adsorption of PTX and CUR drugs and the co-loading of these two drugs are evaluated. Our results show that the strongest interaction energy belongs to the adsorption of drug CUR on the MXNNO-Cu-BTC adsorbent, while the interaction of PTX drug with the MXNO- Cu-BTC in the MXNO-Cu-BTC/PTX&CUR system is the lowest due to the particular structure of the drug and the adsorbent. Our results show that at the beginning simulation, the interaction energy between the PTX drug and water in PTX/MXN system is -4645.48 kJ/mol, which reduces to -3848.71 kJ/mol after the system reaches equilibrium. Therefore, the inspected adsorbents have a good performance in adsorbing CUR and PTX drugs. The obtained results from this investigation provide valuable information about experimental studies by medical scientists in the future.Communicated by Ramaswamy H. Sarma.


Assuntos
Curcumina , Neoplasias , Nitritos , Elementos de Transição , Paclitaxel/farmacologia , Paclitaxel/química , Curcumina/farmacologia , Curcumina/química , Adsorção , Cobre/química , Água , Neoplasias/tratamento farmacológico
17.
J Pept Sci ; 30(3): e3547, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37752675

RESUMO

Argireline (Ac-EEMQRR-NH2 ), a well-known neurotransmitter peptide with a potency similar to botulinum neurotoxins, reveals a proven affinity toward Cu(II) ions. We report herein Cu(II) chelating properties of three new Argireline derivatives, namely, AN4 (Ac-EAHRR-NH2 ), AN5 (Ac-EEHQRR-NH2 ), and AN6 (Ac-EAHQRK-NH2 ). Two complementary experimental techniques, i.e., potentiometric titration (PT) and isothermal titration calorimetry (ITC), have been employed to describe the acid-base properties of the investigated peptides as well as the thermodynamic parameters of the Cu(II) complex formation. Additionally, based on density functional theory (DFT) calculations, we propose the most likely structures of the resulting Cu-peptide complexes. Finally, the cytotoxicity of the free peptides and the corresponding Cu(II) complexes was estimated in human skin cells for their possible future cosmetic application. The biological results were subsequently compared with free Argireline, its Cu(II)-complexes, and the previously studied AN2 derivative (EAHQRR).


Assuntos
Complexos de Coordenação , Cobre , Humanos , Cobre/química , Peptídeos/farmacologia , Peptídeos/química , Oligopeptídeos/química , Íons , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
18.
Small ; 20(15): e2307406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009734

RESUMO

Osteomyelitis caused by deep tissue infections is difficult to cure through phototherapy due to the poor penetration depth of the light. Herein, Cu/C/Fe3O4-COOH nanorod composites (Cu/C/Fe3O4-COOH) with nanoscale tip convex structures are successfully fabricated as a microwave-responsive smart bacteria-capture-killing vector. Cu/C/Fe3O4-COOH exhibited excellent magnetic targeting and bacteria-capturing ability due to its magnetism and high selectivity affinity to the amino groups on the surface of Staphylococcus aureus (S. aureus). Under microwave irradiation, Cu/C/Fe3O4-COOH efficiently treated S. aureus-infected osteomyelitis through the synergistic effects of microwave thermal therapy, microwave dynamic therapy, and copper ion therapy. It is calculated the electric field intensity in various regions of Cu/C/Fe3O4-COOH under microwave irradiation, demonstrating that it obtained the highest electric field intensity on the surface of copper nanoparticles of Cu/C/Fe3O4-COOH due to its high-curvature tips and metallic properties. This led to copper nanoparticles attracted more charged particles compared with other areas in Cu/C/Fe3O4-COOH. These charges are easier to escape from the high curvature surface of Cu/C/Fe3O4-COOH, and captured by adsorbed oxygen, resulting in the generation of reactive oxygen species. The Cu/C/Fe3O4-COOH designed in this study is expected to provide insight into the treatment of deep tissue infections under the irradiation of microwave.


Assuntos
Nanopartículas , Osteomielite , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Cobre/química , Micro-Ondas/uso terapêutico , Nanopartículas/química , Infecções Estafilocócicas/terapia , Osteomielite/terapia
19.
J Colloid Interface Sci ; 657: 1-14, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38029524

RESUMO

Nanodrug delivery systems (NDSs), such as mesoporous silica, have been widely studied because of their high specific surface area, high loading rate, and easy modification; however, they are not easily metabolized and excreted by the human body and may be potentially harmful. Hence, we aimed to examine the synergistic anti-tumor effects of ex vivo chemo-photothermal therapy to develop a rational and highly biocompatible treatment protocol for tumors. We constructed a biodegradable NDS using organic mesoporous silica with a tetrasulfide bond structure, copper sulfide core, and folic acid-modified surface (CuS@DMONs-FA-DOX-PEG) to target a tumor site, dissociate, and release the drug. The degradation ability, photothermal conversion ability, hemocompatibility, and in vitro and in vivo anti-tumor effects of the CuS@DMONs-FA-DOX-PEG nanoparticles were evaluated. Our findings revealed that the nanoparticles encapsulated in copper sulfide exhibited significant photothermal activity and optimal photothermal conversion rate. Further, the drug was accurately delivered and released into the target tumor cells, annihilating them. This study demonstrated the successful preparation, safety, and synergistic anti-tumor effects of chemo-photothermal therapeutic nanomaterials.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Doxorrubicina , Cobre/farmacologia , Cobre/química , Terapia Fototérmica , Dióxido de Silício/química , Fototerapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanopartículas/química , Sulfetos/farmacologia , Concentração de Íons de Hidrogênio
20.
Artigo em Inglês | MEDLINE | ID: mdl-37853634

RESUMO

Copper sulfide based phototherapy, including photothermal therapy and photodynamic therapy, is an emerging minimally invasive treatment of tumor, which the light was converted to heat or reactive oxygen to kill the tumor cells. Compared with conventional chemotherapy and radiation therapy, Cu2-x S based phototherapy is more efficient and has fewer side effects. However, considering the dose-dependent toxicity of Cu2-x S, the performance of Cu2-x S based phototherapy still cannot meet the requirement of the clinical application to now. To overcome this limitation, engineering of Cu2-x S to improve the phototherapy performance by increasing light absorption has attracted extensive attention. For better guidance of Cu2-x S engineering, we outline the currently engineering method being explored, including (1) structural engineering, (2) compositional engineering, (3) functional engineering, and (4) performance engineering. Also, the relationship between the engineering method and phototherapy performance was discussed in this review. In addition, the further development of Cu2-x S based phototherapy is prospected, including smart materials based phototherapy, phototherapy induced immune microenvironment modulation et al. This review will provide new ideas and opportunities for engineering of Cu2-x S with better phototherapy performance. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Cobre/química , Cobre/farmacologia , Fototerapia/métodos , Sulfetos/química , Sulfetos/farmacologia , Neoplasias/terapia , Nanopartículas/química , Microambiente Tumoral
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