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1.
Langmuir ; 40(21): 11087-11097, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38718184

RESUMO

Photocatalytic technology is an attractive option for environmental remediation because of its green and sustainable nature. However, the inefficient utilization of solar energy and powder morphology currently impede its practical application. Here, we designed a floatable photocatalyst by anchoring 0D Cu2(OH)PO4 (CHP) nanoparticles on 2D graphene to construct 0D/2D CHP/reduced graphene oxide (rGO) aerogels. The CHP/rGO aerogels have interconnected mesopores that provide a large surface area, promoting particle dispersion and increasing the number of active sites. Moreover, the optical response of the CHP/rGO aerogel has been significantly expanded to cover the full spectrum of the solar light. Notably, the 20%CHP/rGO aerogel displayed a high degradation rate (k = 0.178 min-1) taking methylene blue (MB) as a model pollutant under light irradiation (λ > 420 nm). The enhanced photocatalytic activity is ascribed to the rapid electron transfer in the CHP/rGO heterostructures, as supported by the DFT theoretical calculations. Our research highlights the utilization of full spectrum responsive photocatalysts for the elimination of organic pollutants from wastewater under solar light irradiation, as well as the potential for catalyst recovery using floatable aerogels to meet industrial requirements.

2.
Int J Biol Macromol ; 235: 123868, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870639

RESUMO

Metal-organic frameworks (MOFs) have a potential application in blood purification, but their microcrystalline nature has hampered their industrial application. Here, novel MOFs-polymer beads based on UiO, sodium alginate, polyacrylic acid, and poly (ethylene imine) were prepared and applied as a whole blood hemoadsorbent for the first time. The amidation among polymers immobilized UiO66-NH2 into the network of the optimal product (SAP-3), and the NH2 of UiO66-NH2 significantly increased the removal rate (70 % within 5 min) of SAP-3 on bilirubin. The adsorption of SAP-3 on bilirubin mainly obeyed the pseudo-second-order kinetic, Langmuir isotherm and Thomas models with a maximum adsorption capacity (qm) of 63.97 mg·g-1. Experimental and density functional theory simulation results show that bilirubin was mainly adsorbed by UiO66-NH2via electrostatic force, hydrogen bonding, and π-π interactions. Notably, the adsorption in vivo show that the total bilirubin removal rate in the whole blood of the rabbit model was up to 42 % after 1 h of adsorption. Given its excellent stability, cytotoxicity, and hemocompatibility, SAP-3 has a great potential in hemoperfusion therapy. This study proposes an effective strategy for settling the powder property of MOFs and could provide experimental and theoretical references for application of MOFs in blood purification.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Animais , Coelhos , Bilirrubina/química , Heparina , Polímeros/química , Adsorção , Etilenos , Poluentes Químicos da Água/química
3.
RSC Adv ; 13(12): 8281-8290, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36926008

RESUMO

The food sector uses methyl yellow (MY) extensively as a colorant. The primary transporter in vivo that influences MY absorption, metabolism, distribution, and excretion is human serum albumin (HSA). Exploring the binding process and looking at how HSA and MY work physiologically at the molecular level is therefore very important. Experiments using steady-state fluorescence and fluorescence lifetimes proved that HSA and MY's quenching mechanisms were static. The HSA-MY complex's binding constant was estimated using thermodynamic parameters to be around 104 M-1. The hydrophobic forces were a major factor in the binding process, as evidenced by the negative ΔG, positive ΔH, and ΔS, which suggested that this contact was spontaneous. Site tests showed that MY linked to HSA's site I. Circular dichroism and three-dimensional fluorescence analysis revealed that the 1.33% α-helix content dropped and the amino acid microenvironment altered. While HSA's protein surface hydrophobicity decreased when engaging MY, the binding of MY to HSA reduced in the presence of urea. The stability of the system was assessed using molecular modeling. Additionally, HSA's esterase-like activity decreased when MY was present, and Ibf/Phz affected the inhibition mechanism of MY on HSA. These findings offer a distinctive perspective for comprehending the structure and functioning of HSA and evaluating the safety of MY.

4.
J Hazard Mater ; 435: 129042, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35650723

RESUMO

The biocompatibility of metal-organic frameworks (MOFs) is necessary to humans but is far from being sufficiently addressed. This study focused on the effects of microsize on the biocompatibility of MOFs by selecting UiO67 with micron and submicron size as the MOFs models. Under the dose metric of surface area, the binding constant between UiO67 and human serum albumin (HSA) gradually increased with increased UiO67 size. Submicron UiO67 induced stronger conformational transformation and more greatly affected the protein surface hydrophobicity than micron UiO67. Micron UiO67 also inhibited the esterase-like activity of HSA through competitive inhibition mechanism, whereas submicron UiO67 inhibited it through noncompetitive inhibition mechanism. The size of UiO67 had little effect on hemocompatibility. A smaller size of UiO67, corresponded with a higher IC50 value for 293 T and LO2 cells, and the adsorption of HSA can effectively improve cytotoxicity. In vivo toxicity evaluations revealed that all UiO67 did not cause obvious distortion of organs, and they were metabolized primarily in the kidney. These results provided useful information about the toxicity of MOFs and experimental references for the development of MOFs-based engineering materials.


Assuntos
Estruturas Metalorgânicas , Adsorção , Humanos , Estruturas Metalorgânicas/química , Albumina Sérica Humana
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120868, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35032760

RESUMO

As a new form of nicotine introduction for novel tobacco products, the interaction of nicotine salt with biological macromolecules may differ from that of free nicotine and thus affect its transport and distribution in vivo. Hence, the mechanism underlying the interaction between 2,6-dihydroxybenzoic acid nicotine salt (DBN) and human serum albumin (HSA) was investigated by multi-spectroscopy, molecular docking, and dynamic simulation. Experiments on steady-state fluorescence and fluorescence lifetime revealed that the quenching mechanism of DBN and HSA was dynamic quenching, and binding constant was in the order of 10^4 L mol-1. Thermodynamic parameters exhibited that the binding was a spontaneous process with hydrophobic forces as the main driving force. Fluorescence competition experiments revealed that DBN bound to site I of HSA IIA subdomain. According to the results of synchronous fluorescence, 3D fluorescence, FT-IR spectroscopy, circular dichroism (CD) spectroscopy, and molecular dynamics (MD) simulation, DBN did not affect the basic skeleton structure of HSA but changed the microenvironment around the amino acid residues. Computer simulations positively corroborated the experimental results. Moreover, DBN decreased the surface hydrophobicity and weakened the esterase-like activity of HSA, leading to the impaired function of the latter. This work provides important information for studying the interaction between DBN as a nicotine substitute and biological macromolecules and contributes to the further development and application of DBN.


Assuntos
Simulação de Dinâmica Molecular , Albumina Sérica Humana , Sítios de Ligação , Dicroísmo Circular , Humanos , Hidroxibenzoatos , Simulação de Acoplamento Molecular , Nicotina , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
6.
J Mater Chem B ; 9(42): 8768-8778, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34585713

RESUMO

HER2+ breast cancer is highly aggressive and proliferative even after multiple chemotherapy regimens. At present, the available clinical treatment duration of chemotherapeutic agents is limited by severe toxicity to noncancerous tissues, which are attributed to insufficient targeting. Here, we designed an active-targeted and pH-responsive liposome to improve the treatment. The ideas were as follows: (1) using liposome as a nano-delivery system for HER2 inhibitor (lapatinib; LAP) to reduce the toxicity; (2) modifying the capsule with T7 peptide for specific targeted delivery to the tumor cells, and (3) enabling the capsule with the pH-sensitive ability and triggering sustained drug release at extracellular weakly acidic microenvironment to emerge toxicity in tumors and to improve curative effects. It was found that T7 peptide-modified pH-sensitive liposome (T7-LP) was more effective and safer than free drug and unmodified liposome, and reduced drug-induced side effects and noncancerous toxicity. These results support the application potential of T7-LP in improving the efficacy of LAP in HER2+ breast cancer treatment. It might be a novel LAP formulation as a clinical agent.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Colágeno Tipo IV/química , Lapatinib/farmacologia , Fragmentos de Peptídeos/química , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Animais , Antineoplásicos/química , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Lapatinib/química , Lipossomos/química , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Imagem Óptica , Inibidores de Proteínas Quinases/química , Ratos , Ratos Sprague-Dawley , Receptor ErbB-2/metabolismo
7.
ACS Appl Mater Interfaces ; 13(39): 46588-46597, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34554746

RESUMO

The surface feature of solid electrolytes fundamentally governs their own physical properties and significantly affects the interaction with the electrode materials. The evaluation of interfacial contact between the electrolyte and the metallic anode is largely relied on the macroscopic contact angle measurement, which is influenced by the intrinsic wettability and the microstructure of the electrolyte. In this work, the surface chemistry of the solid electrolyte is first regulated via facile thermal treatments. Then, scanning probe microscopy (SPM)-based techniques are comprehensively adopted to study the interaction between the electrolyte and metallic anode at the nanoscale. By manipulating the overpotential applied on the SPM tip, the mobile sodium ions at the subsurface of the solid electrolyte can be extracted toward the surface, and the eventual topography of the products is deliberately correlated with the sodium wettability. In this context, the impact of surface treatment on the sodium wettability of the surface layer is systematically evaluated based on the topographic evolution at the nanoscale. Furthermore, the local electrochemical reaction dynamics is revealed by correlating the surface ionic activity and current-voltage (I-V) curves. This work presents a new methodology to effectively evaluate the sodium wettability of the solid electrolyte, and these findings can provide meaningful implications to the surface engineering of ceramic electrolytes for high-performance solid-state batteries.

8.
ACS Appl Mater Interfaces ; 13(29): 34320-34331, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34275274

RESUMO

Dendrite growth under large current density is the key intrinsic issue impeding a wider application of Li metal anodes. Previous studies mainly focused on avoiding dendrite growth by building an additional interface layer or surface modification. However, the mechanism and factors affecting dendrite growth for Li metal anodes are still unclear. Herein, we analyze the causes for dendrite growth, which leads us to suggest three-dimensional (3D) metal anodes as a promising approach to overcome the dendrite issues. A 3D composite Li anode was prepared from renewable carbonized wood doped with Sn to demonstrate its superior electrochemical performance compared with Li foils. The anode was cycled at various current densities from 0.1 to 10 mA cm-2 for five cycles at each current density, displaying low overpotential compared with conventional Li foils. Long galvanostatic cycling at 1 mA cm-2 for 1000 h and at 2 mA cm-2 for 500 h was achieved without dendrite growth. Further analysis reveals that the 3D structure facilitates surface diffusion by increasing the surface area from 5.23 × 10-3 m2 g-1 (Li foil) to 2.64 m2 g-1 and by creating nanoscale separation walls. The tin alloying effectively prevents non-uniform lithium plating by creating abundant nucleation centers. Additionally, suitable alloying elements for a wider range of 3D Li anodes have been identified from density functional theory calculations.

9.
Int J Biol Macromol ; 184: 101-108, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119545

RESUMO

Lentinan is a natural ß-glucan with various bioactivities and is combined with chemotherapy drugs for cancer treatment. Regorafenib is an oral multi-kinase inhibitor approved by FDA for treatment of metastatic colorectal cancer, advanced hepatocellular carcinoma, and metastatic gastrointestinal stromal tumors. Regorafenib has poor water solubility and multiple toxicities. We report drug-drug nanosuspensions of regorafenib and lentinan. Results of dynamic light scattering and scanning electron microscopy showed that the mean particle size of the regorafenib-lentinan nanosuspensions was approximately 200 nm and was uniformly distributed. Transmission electron microscopy findings indicated that lentinan stabilized the nanosuspensions by steric manner. Hydrogen bonds and hydrophobic interactions were found between regorafenib and lentinan by molecular dynamics simulation. The results of cytotoxicity assay and pharmacokinetics study in rats showed that the regorafenib-lentinan nanosuspensions reduced the toxicity and enhanced the in vitro anticancer activity and oral bioavailability of regorafenib. Lentinan as a natural stabilizer has the potential using for drug nanosuspensions. Drug-drug nanosuspensions are a new form of combination therapies that can reduce the number of drugs taken by patients and improve their compliance.


Assuntos
Antineoplásicos/administração & dosagem , Lentinano/administração & dosagem , Compostos de Fenilureia/administração & dosagem , Piridinas/administração & dosagem , Administração Oral , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Composição de Medicamentos , Células HCT116 , Células HEK293 , Humanos , Lentinano/química , Lentinano/farmacocinética , Simulação de Dinâmica Molecular , Nanopartículas , Tamanho da Partícula , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacocinética , Piridinas/química , Piridinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Solubilidade , Suspensões
10.
J Colloid Interface Sci ; 601: 418-426, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34087600

RESUMO

Sodium-metal batteries have strong potential to be utilized as stationary high energy density storage devices. Owing to its high ionic conductivity, low electronic conductivity and relatively easy fabrication, NASICON-structure electrolyte (Na3Zr2Si2PO12) is one of the potential candidates to be considered in the solid-state sodium-metal batteries at room temperature. However, the large interfacial resistance between the solid-state electrolyte and the metallic sodium is known to limit the critical current density (CCD) of the cell. In this study, a simple and cost-effective annealing process is introduced to the electrolyte preparation to improves its interface with metallic sodium. X-ray photoelectron spectroscopy and scanning probe microscopy show that Si forms bonds with the surface functional groups when exposed to the ambient condition. With the removal of surface contamination as well as a partially reduced electrolyte surface, the annealed electrolyte shows an extremely small interfacial resistance of 11 Ω cm2 and a high CCD of 0.9 mA cm-2. This study provides an insight on the electrolyte surface preparation and its significant in a sodium-metal solid-state battery.

11.
J Mater Chem B ; 9(28): 5628-5635, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34109969

RESUMO

Hemoperfusion has become the third-generation treatment strategy for patients suffering from hyperbilirubinemia, but adsorbents used for bilirubin removal mostly face intractable problems, such as unsatisfactory adsorption performance and poor hemocompatibility. Metal-organic frameworks (MOFs) are promising adsorbents for hemoperfusion due to their high specific surface areas and easily modified organic ligands. However, their microporous properties and separation have hampered their application. Here, a novel hierarchical core-shell nanoplatform (named Double-PEG) with tailored binding sites and pore sizes based on Fe3O4@C and Uio66-NH2 was constructed. Notably, Double-PEG showed excellent bilirubin uptake of up to 1738.30 mg g-1 and maintained excellent bilirubin removal efficiency in simulated biological solutions. A study on the adsorption mechanism showed that the adsorption of Double-PEG towards bilirubin tended to be chemical adsorption and in accordance with the Langmuir model. Besides, the good separability, recyclability, cytotoxicity and hemocompatibility of Double-PEG show great potential in hemoperfusion therapy. The finding of this study may provide a novel insight into the application of MOF materials in the field of hemoperfusion.


Assuntos
Bilirrubina/isolamento & purificação , Materiais Biocompatíveis/química , Carbono/química , Óxido Ferroso-Férrico/química , Estruturas Metalorgânicas/química , Nanopartículas/química , Adsorção , Bilirrubina/química , Materiais Biocompatíveis/síntese química , Linhagem Celular , Humanos , Cinética , Estruturas Metalorgânicas/síntese química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Purificação da Água
12.
Food Chem ; 359: 129960, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33945987

RESUMO

The interaction between lipase and quercetin 3-rhamnoside was studied by fluorescence spectroscopy, enzyme kinetics, and molecular dynamics simulation. The results showed that quercetin 3-rhamnoside had a strong quenching effect on the intrinsic fluorescence of lipase. The binding constant decreased with increasing temperature, and the number of binding sites approached 1. Thermodynamic parameters indicated that hydrogen bonding and van der Waals forces are the dominant forces when the interaction occurs. Circular dichroism spectroscopy and infrared spectroscopy proved that the ligand perturbed the structure of lipase. Enzyme kinetics results showed that quercetin 3-rhamnoside inhibited lipase, and the inhibitory effect was dose-dependent. Molecular dynamics simulation further explained the interaction mechanism and inhibitory effect. This study confirmed the inhibitory effect of quercetin 3-rhamnoside on lipase explained their binding mechanism, which will contribute to guiding the development of fat-reducing functional foods.


Assuntos
Lipase/metabolismo , Quercetina/metabolismo , Sítios de Ligação , Fluorescência , Ligação de Hidrogênio , Lipase/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Quercetina/química , Espectrometria de Fluorescência/métodos , Temperatura , Termodinâmica
13.
J Pharm Biomed Anal ; 201: 114121, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34020341

RESUMO

Introduction of hydrophilic groups can improve the solubility of leading drugs but inevitably affect their interaction with proteins. This study selected sirtuin inhibitors Tenovin-1 (T1) and Tenovin-6 (T6) as drug models to determine differences in binding mode to human serum albumin (HSA). T1 and T6 quenched the endogenous fluorescence of HSA via static quenching mechanism. Introduction of hydrophilic groups greatly reduced the binding constant, i.e., from 1.302 × 104 L mol-1 for the HSA-T6 system to 0.128 × 104 L mol-1 for the HSA-T1 system. HSA-T1 system was mainly driven by electrostatic interactions while that of HSA-T6 system was hydrophobic interaction and both systems were spontaneous reactions. Site marker experiments and molecular docking indicated that both systems mainly bound to the hydrophobic site I of HSA. Molecular dynamics (MD) simulation analysis further revealed that Tyr148, Tyr150 and Arg257 residues played a key role in this recognition process for both systems. In particular, T6 maintained additional several hydrogen bonds with the surrounding residues. T1 had almost no effect on the esterase-like activity of HSA, but T6 inhibited the hydrolysis of p-NPA. Furthermore, differential scanning calorimetry (VP-DSC), circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy confirmed that HSA in the T6 system undergone a more significant conformational transition than that in the T1 system.


Assuntos
Preparações Farmacêuticas , Sirtuínas , Acetanilidas , Benzamidas , Sítios de Ligação , Dicroísmo Circular , Humanos , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência , Termodinâmica , Tioureia/análogos & derivados
14.
Allergy Asthma Clin Immunol ; 17(1): 38, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865428

RESUMO

BACKGROUND: IL-35 is a newly anti-inflammatory cytokine that belongs to the IL-12 family. Mast cells, as one of the major effector cells in the immune response system, plays an important role in the pathogenesis of chronic spontaneous urticarial (CSU). Our study aims to explore the inhibited role of IL-35 in HMC-1. METHODS: The effects of IL-35 on cell proliferation, cytokine expression, and histamine release in a human mast cell line (HMC-1) were investigated by CCK8, ELISA, or RT-PCR. The phosphorylation levels of ERK1/2, p38, and JNK1/2, in PMA plus A23187 induced HMC-1 cells was detected by Western Blot. RESULTS: We found that IL-35 significantly inhibited the proliferation of HMC-1 cells stimulated by PMA and A23187. IL-35 also down-regulates the release of histamine and the mRNA expression of IL-6 and IL-17 in activated HMC-1. Furthermore, IL-35 markedly inhibited the phosphorylation levels of ERK1/2, p38, and JNK1/2, in PMA plus A23187 induced HMC-1 cells. CONCLUSIONS: This study provides the first observations on the inhibitory and anti-inflammatory effect of IL-35 in activated HMC-1 cells. We suggest that IL35 may play an inhibited role in the pathogenesis of CSU.

15.
Spectrochim Acta A Mol Biomol Spectrosc ; 258: 119828, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-33930850

RESUMO

Ligand-receptor molecular recognitionis the basis of biological process. The Saturation Transfer Difference-NMR (STD-NMR) technique has been recently used to gain qualitative and quantitative information about physiological interactions at atomic-resolution. The molecular recognition patterns between Vitamin B12 (VB12) and human serum albumin (HSA) were investigated by STD-NMR supplemented by other spectroscopies and molecular docking. STD-NMR delivered a complete picture that the substituent groups on the tetrapyrrole ring of VB12 interacted with site III of HSA through binding epitope mapping and competitive probe experiments. STD-NMR and fluorescence results proved the moderate binding capability of VB12 and clarified a static, spontaneous, and temperature-sensitive binding mechanism. 3D-fluorencence, FT-IR and circular dichroism spectra showed a compact protein structure by interacting with VB12. Size distribution and surface hydrophobicity showed the surface properties changes of HSA caused by the binding of VB12. Computer simulation confirmed the recognition mode in theory and was compared with experiments. This work is beneficial for understanding the safety and biological action of VB12, and will attract researchers interested in NMR technology.


Assuntos
Albumina Sérica Humana , Vitamina B 12 , Sítios de Ligação , Dicroísmo Circular , Simulação por Computador , Humanos , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
16.
Colloids Surf B Biointerfaces ; 201: 111644, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33639512

RESUMO

The clinical efficacy of lenvatinib (LFT) is limited by its poor aqueous solubility and low bioavailability. In this work, LFT-loaded soy phospholipid and sodium glycocholate mixed micelles (LFT-MMs) were prepared through classical co-precipitation. And it was served as an oral administration to address these shortcomings. The preparation conditions were optimized by single-factor experiments. The mass ratio of PC, SGC and LFT, and the species of dispersing media were proved to be decisive factors in controlling the properties of LFT-MMs. The optimal LFT-MMs presented prominent enhancement (500-fold) in LFT solubility, high encapsulation efficiency (87.6 %) as well as suitable stability (>1 month at 4 °C). The biocompatibility of LFT-MMs was estimated by in vitro serum stability measurement and hemolysis test. It showed that serum proteins hardly adhered to the surface of LFT-MMs, and insignificant hemolytic rate (<0.5 %) was observed at the micelles concentration below 1 mg/mL. Cytotoxicity test (MTT assay) was carried out to judge the in vitro antitumor activity. LFT-MMs showed an enhanced inhibitory activity against two main kinds of differentiated thyroid cancer cells over LFT and LFT Mesylate. To estimate the in vivo oral bioavailability of LFT-MMs, SD rats were used as animal model. Notably, the relative bioavailability of LFT-MMs compared with the original form of LFT was 176.7 %. These superior characteristics indicated that the mixed micelles are promising water-soluble formulations suitable for LFT oral delivery.


Assuntos
Micelas , Fosfolipídeos , Administração Oral , Animais , Disponibilidade Biológica , Portadores de Fármacos , Tamanho da Partícula , Compostos de Fenilureia , Quinolinas , Ratos , Ratos Sprague-Dawley , Solubilidade
17.
Chemosphere ; 270: 129431, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33388505

RESUMO

Tonalide (AHTN) is a new category of pollutants with a wide range of potential environmental and organismal hazards due to its persistence and lipophilicity, and the safety evaluation of this pollutant under physiological condition is a pressing issue. This study investigated the mechanism of interaction between AHTN and human serum albumin (HSA) that is an important transporter in plasma using multiple spectroscopic, molecular docking, and dynamics simulation methods. The steady-state fluorescence and fluorescence lifetime experiments showed that AHTN quenches the inherent fluorescence of HSA through a static quenching mechanism. Thermodynamic parameters exhibited that the binding constant of AHTN and HSA is of the order of 10^4 L/mol, and the binding is a spontaneous process of moderate strength with hydrophobic forces as the main driving force. Site competition revealed that AHTN binds to site I of HSA IIA subdomain, which was evidenced by the molecular docking results. AHTN altered the HSA amino acid microenvironment and conformation can be derived from three-dimensional fluorescence, circular dichroism spectroscopy, and molecular dynamics simulation. The computer simulations corroborate the experimental results positively. Moreover, AHTN acted as a competitive inhibitor to weaken the esterase-like activity of HSA, leading to impaired function of HSA. Results suggest that interactions between AHTN and HSA may affect the normal structure and activities of the protein, this insight will be helpful to provide some basic information to further explore the potential hazards of AHTN in humans.


Assuntos
Poluentes Ambientais , Albumina Sérica Humana , Sítios de Ligação , Dicroísmo Circular , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência , Tetra-Hidronaftalenos , Termodinâmica
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 119040, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33068900

RESUMO

The interaction between a DPP-4 inhibitor, alogliptin benzoate (AB), and human serum albumin (HSA) was systematically investigated via spectroscopy, microcalorimetry and molecular simulations. Steady-state fluorescence and time-resolved fluorescence spectrometry illustrated that the fluorescence quenching type of AB to HSA was static and caused by the formation of ground state AB-HSA complex. Isothermal titration calorimetry (ITC) combined with fluorescence spectra revealed that the affinity of AB to the subdomain IIA of HSA was moderate with a binding constant in the order of 104. Molecular docking analysis and thermodynamic parameters demonstrated that this combination was maintained by hydrogen bonding along with van der Waals force and hydrophobic force. Circular dichroism and three-dimensional (3D) fluorescence showed that AB increased the hydrophobicity of Trp residue and the α-helix content of HSA by 1.99%. Microdifferential scanning calorimetry revealed that the addition of AB enhanced the thermal stability of HSA. The action forces, binding stability, binding sites, and protein structure of the AB-HSA system were evaluated via molecular dynamics analysis in the simulated environment. On the basis of molecular docking, MD simulation constructed a more reliable 3D model of the AB-HSA complex in terms of spatial structure.


Assuntos
Simulação de Dinâmica Molecular , Albumina Sérica Humana , Benzoatos , Sítios de Ligação , Calorimetria , Dicroísmo Circular , Humanos , Simulação de Acoplamento Molecular , Piperidinas , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência , Termodinâmica , Uracila/análogos & derivados
19.
Front Immunol ; 11: 2032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133061

RESUMO

In our previous study, we have found increased serum levels of HMGB1 in patients with Henoch- Schonlein purpura (HSP), allergic vasculitis (AV), and urticarial vasculitis (UV) and altered HMGB1 distribution in lesional skin in patients with HSP. HMGB1 plays a pro-inflammatory role in the pathogenesis of HSP. To further investigate the role of HMGB1 in the pathogenic mechanism of vasculitis, we investigated the anti-inflammatory effects of HMGB1 blockades (including anti-HMGB1 mAb and glycyrrhizin) in a mouse model of a cutaneous reverse passive Arthus (RPA) reaction. A total of 36 balb/c mice were randomly divided into four groups: the control group, IC model group, HMGB1 monoclonal antibody (anti-HMGB1-mAb) group and the glycyrrhizin group, with nine mice in each group. A cutaneous RPA reaction mouse model was established by injections of the OVA antibody and the OVA antigen. Mice of the anti-HMGB1-mAb group and glycyrrhizin group were pre-treated with anti-HMGB1 mAb or glycyrrhizin, respectively, before the RPA reaction. Our results indicated that HMGB1 blockades (anti-HMGB1 mAb and glycyrrhizin) obviously extenuated the severity of vasculitis skin damage and improved the histological evolvement of inflammatory cells infiltration, vascular fibroid necrosis, and vasodilation in a cutaneous RPA reaction mouse model. In addition, HMGB1 blockades reduced the infiltration of neutrophils, DCs, and T cells and decreased the mRNA expression of IL-6 and CCL5 in skin lesions in the cutaneous RPA reaction mouse model. We suggest that HMGB1 blockades may represent a new direction for the treatment of cutaneous vasculitis.


Assuntos
Anti-Inflamatórios/farmacologia , Proteína HMGB1/antagonistas & inibidores , Vasculite Leucocitoclástica Cutânea/etiologia , Vasculite Leucocitoclástica Cutânea/metabolismo , Animais , Biomarcadores , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Expressão Gênica , Ácido Glicirrízico/farmacologia , Imuno-Histoquímica , Camundongos , Vasculite Leucocitoclástica Cutânea/tratamento farmacológico , Vasculite Leucocitoclástica Cutânea/patologia
20.
Angew Chem Int Ed Engl ; 59(23): 8991-8997, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32078223

RESUMO

In hunting for safe and cost-effective materials for post-Li-ion energy storage, the design and synthesis of high-performance solid electrolytes (SEs) for all-solid-state batteries are bottlenecks. Many issues associated with chemical stability during processing and storage and use of the SEs in ambient conditions need to be addressed. Now, the effect of water as well as oxyhdryl group (. OH) on NaBi3 O4 Cl2 are investigated by evaluating ionic conductivity. The presence of water and . OH results in an increase in ionic conductivity of NaBi3 O4 Cl2 owing to diffusion of H2 O into NaBi3 O4 Cl2 , partially forming binding . OH through oxygen vacancy repairing. Ab initio calculations reveal that the electrons significantly accumulate around . OH and induce a more negative charge center, which can promote Na+ hopping. This finding is fundamental for understanding the essential role of H2 O in halide-based SEs and provides possible roles in designing water-insensitive SEs through control of defects.

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