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1.
Cell ; 176(1-2): 1, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30633900

RESUMO

During the postpartum period, the brain's inhibitory GABAA receptors may not recover in time following their reduced numbers during pregnancy. This is likely the cause of postpartum depression prevalent in ∼12% of childbearing women. A new therapy for this condition consists of administering a synthetic neurosteroid during the postpartum period to alleviate the mood disorder. To view this Bench to Bedside, open or download the PDF.


Assuntos
Depressão Pós-Parto/terapia , Pregnanolona/farmacologia , Receptores de GABA-A/metabolismo , beta-Ciclodextrinas/farmacologia , Adulto , Depressão Pós-Parto/metabolismo , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/terapia , Combinação de Medicamentos , Feminino , Humanos , Transtornos do Humor , Neurotransmissores/farmacologia , Período Pós-Parto/metabolismo , Gravidez , Prevalência , Receptores de GABA-A/fisiologia
2.
Nature ; 590(7846): 509-514, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568813

RESUMO

Mechanosensitive channels sense mechanical forces in cell membranes and underlie many biological sensing processes1-3. However, how exactly they sense mechanical force remains under investigation4. The bacterial mechanosensitive channel of small conductance, MscS, is one of the most extensively studied mechanosensitive channels4-8, but how it is regulated by membrane tension remains unclear, even though the structures are known for its open and closed states9-11. Here we used cryo-electron microscopy to determine the structure of MscS in different membrane environments, including one that mimics a membrane under tension. We present the structures of MscS in the subconducting and desensitized states, and demonstrate that the conformation of MscS in a lipid bilayer in the open state is dynamic. Several associated lipids have distinct roles in MscS mechanosensation. Pore lipids are necessary to prevent ion conduction in the closed state. Gatekeeper lipids stabilize the closed conformation and dissociate with membrane tension, allowing the channel to open. Pocket lipids in a solvent-exposed pocket between subunits are pulled out under sustained tension, allowing the channel to transition to the subconducting state and then to the desensitized state. Our results provide a mechanistic underpinning and expand on the 'force-from-lipids' model for MscS mechanosensation4,11.


Assuntos
Microscopia Crioeletrônica , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/ultraestrutura , Escherichia coli/química , Canais Iônicos/metabolismo , Canais Iônicos/ultraestrutura , Membranas Artificiais , Fosfatidilcolinas/metabolismo , Detergentes/farmacologia , Escherichia coli/ultraestrutura , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Interações Hidrofóbicas e Hidrofílicas , Canais Iônicos/química , Canais Iônicos/genética , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Mecanotransdução Celular/efeitos dos fármacos , Modelos Moleculares , Mutação , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacologia , Conformação Proteica/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia
3.
J Biol Chem ; 300(1): 105484, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992804

RESUMO

Sterols are hydrophobic molecules, known to cluster signaling membrane-proteins in lipid rafts, while methyl-ß-cyclodextrin (MßCD) has been a major tool for modulating membrane-sterol content for studying its effect on membrane proteins, including the transient receptor potential (TRP) channels. The Drosophila light-sensitive TRP channels are activated downstream of a G-protein-coupled phospholipase Cß (PLC) cascade. In phototransduction, PLC is an enzyme that hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) generating diacylglycerol, inositol-tris-phosphate, and protons, leading to TRP and TRP-like (TRPL) channel openings. Here, we studied the effects of MßCD on Drosophila phototransduction using electrophysiology while fluorescently monitoring PIP2 hydrolysis, aiming to examine the effects of sterol modulation on PIP2 hydrolysis and the ensuing light-response in the native system. Incubation of photoreceptor cells with MßCD dramatically reduced the amplitude and kinetics of the TRP/TRPL-mediated light response. MßCD also suppressed PLC-dependent TRP/TRPL constitutive channel activity in the dark induced by mitochondrial uncouplers, but PLC-independent activation of the channels by linoleic acid was not affected. Furthermore, MßCD suppressed a constitutively active TRP mutant-channel, trpP365, suggesting that TRP channel activity is a target of MßCD action. Importantly, whole-cell voltage-clamp measurements from photoreceptors and simultaneously monitored PIP2-hydrolysis by translocation of fluorescently tagged Tubby protein domain, from the plasma membrane to the cytosol, revealed that MßCD virtually abolished the light response when having little effect on the light-activated PLC. Together, MßCD uncoupled TRP/TRPL channel gating from light-activated PLC and PIP2-hydrolysis suggesting the involvement of distinct nanoscopic lipid domains such as lipid rafts and PIP2 clusters in TRP/TRPL channel gating.


Assuntos
Proteínas de Drosophila , Lipídeos de Membrana , Canais de Potencial de Receptor Transitório , Fosfolipases Tipo C , beta-Ciclodextrinas , Animais , beta-Ciclodextrinas/farmacologia , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Lipídeos de Membrana/metabolismo , Células Fotorreceptoras de Invertebrados/efeitos dos fármacos , Células Fotorreceptoras de Invertebrados/metabolismo , Esteróis/metabolismo , Canais de Potencial de Receptor Transitório/efeitos dos fármacos , Canais de Potencial de Receptor Transitório/genética , Canais de Potencial de Receptor Transitório/metabolismo , Fosfolipases Tipo C/metabolismo , Transdução de Sinal Luminoso/efeitos dos fármacos
4.
Nat Methods ; 18(3): 316-320, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33542509

RESUMO

We report a means by which atomic and molecular secondary ions, including cholesterol and fatty acids, can be sputtered through single-layer graphene to enable secondary ion mass spectrometry (SIMS) imaging of untreated wet cell membranes in solution at subcellular spatial resolution. We can observe the intrinsic molecular distribution of lipids, such as cholesterol, phosphoethanolamine and various fatty acids, in untreated wet cell membranes without any labeling. We show that graphene-covered cells prepared on a wet substrate with a cell culture medium reservoir are alive and that their cellular membranes do not disintegrate during SIMS imaging in an ultra-high-vacuum environment. Ab initio molecular dynamics calculations and ion dose-dependence studies suggest that sputtering through single-layer graphene occurs through a transient hole generated in the graphene layer. Cholesterol imaging shows that methyl-ß-cyclodextrin preferentially extracts cholesterol molecules from the cholesterol-enriched regions in cell membranes.


Assuntos
Membrana Celular/metabolismo , Colesterol/análise , Etanolaminas/análise , Ácidos Graxos/análise , Espectrometria de Massa de Íon Secundário/métodos , Diagnóstico por Imagem , Grafite/química , Simulação de Dinâmica Molecular , Análise de Célula Única/métodos , beta-Ciclodextrinas/química
5.
Chem Res Toxicol ; 37(5): 757-770, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38625865

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are known for their high environmental persistence and potential toxicity. The presence of PFAS has been reported in many dairy products. However, the mechanisms underlying the accumulation of PFAS in these products remain unclear. Here, we used native mass spectrometry and molecular dynamics simulations to probe the interactions between 19 PFAS of environmental concern and two isoforms of the major bovine whey protein ß-lactoglobulin (ß-LG). We observed that six of these PFAS bound to both protein isoforms with low- to mid-micromolar dissociation constants. Based on quantitative, competitive binding experiments with endogenous ligands, PFAS can bind orthosterically and preferentially to ß-LG's hydrophobic ligand-binding calyx. ß-Cyclodextrin can also suppress binding of PFAS to ß-LG owing to the ability of ß-cyclodextrin to directly sequester PFAS from solution. This research sheds light on PFAS-ß-LG binding, suggesting that such interactions could impact lipid-fatty acid transport in bovine mammary glands at high PFAS concentrations. Furthermore, our results highlight the potential use of ß-cyclodextrin in mitigating PFAS binding, providing insights toward the development of strategies to reduce PFAS accumulation in dairy products and other biological systems.


Assuntos
Fluorocarbonos , Lactoglobulinas , Leite , Animais , Lactoglobulinas/metabolismo , Lactoglobulinas/química , Bovinos , Leite/química , Leite/metabolismo , Fluorocarbonos/química , Fluorocarbonos/metabolismo , Simulação de Dinâmica Molecular , beta-Ciclodextrinas/química , beta-Ciclodextrinas/metabolismo , Sítios de Ligação , Ligação Proteica
6.
J Clin Psychopharmacol ; 44(3): 240-249, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38551454

RESUMO

PURPOSE/BACKGROUND: Brexanolone is approved for postpartum depression (PPD) by the United States Food and Drug Administration. Brexanolone has outperformed placebo in clinical trials, but less is known about the efficacy in real-world patients with complex social and medical histories. Furthermore, the impact of brexanolone on large-scale brain systems such as changes in functional connectivity (FC) is unknown. METHODS/PROCEDURES: We tracked changes in depressive symptoms across a diverse group of patients who received brexanolone at a large medical center. Edinburgh Postnatal Depression Scale (EPDS) scores were collected through chart review for 17 patients immediately prior to infusion through approximately 1 year postinfusion. In 2 participants, we performed precision functional neuroimaging (pfMRI), including before and after treatment in 1 patient. pfMRI collects many hours of data in individuals for precision medicine applications and was performed to assess the feasibility of investigating changes in FC with brexanolone. FINDINGS/RESULTS: The mean EPDS score immediately postinfusion was significantly lower than the mean preinfusion score (mean change [95% CI]: 10.76 [7.11-14.40], t (15) = 6.29, P < 0.0001). The mean EPDS score stayed significantly lower at 1 week (mean difference [95% CI]: 9.50 [5.23-13.76], t (11) = 4.90, P = 0.0005) and 3 months (mean difference [95% CI]: 9.99 [4.71-15.27], t (6) = 4.63, P = 0.0036) postinfusion. Widespread changes in FC followed infusion, which correlated with EPDS scores. IMPLICATIONS/CONCLUSIONS: Brexanolone is a successful treatment for PPD in the clinical setting. In conjunction with routine clinical care, brexanolone was linked to a reduction in symptoms lasting at least 3 months. pfMRI is feasible in postpartum patients receiving brexanolone and has the potential to elucidate individual-specific mechanisms of action.


Assuntos
Depressão Pós-Parto , Estudos de Viabilidade , Pregnanolona , beta-Ciclodextrinas , Humanos , Feminino , Adulto , Pregnanolona/administração & dosagem , Pregnanolona/farmacologia , Projetos Piloto , Depressão Pós-Parto/tratamento farmacológico , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/farmacologia , Neuroimagem Funcional , Combinação de Medicamentos , Adulto Jovem , Resultado do Tratamento , Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética
7.
Mol Pharm ; 21(5): 2383-2393, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38551360

RESUMO

Nanocone clusters (NCCs) have been developed as clusters with inclusion complexes of FDA-approved ß-cyclodextrin (ßCD) and perfluorocarbons (PFC) (i.e., perfluoropentane (PFP) and perfluorohexane (PFH)) and have shown promise in nanoparticle-mediated histotripsy (NMH) applications owing to their lowered cavitation threshold, ease of production, and fluorocarbon quantification. However, there is still a lack of information on the best conditions of the synthesis of NCCs as a product that can have a maximum determinable fluorocarbon content and maintain the stability of the NCC during synthesis and when used as histotripsy agents or exposed to physiological conditions. These concerns about the stability of the clusters and the best possible formulation are investigated in the current work. The cluster formation potential was tested taking into consideration the nature of both PFCs and ßCD by employing different synthesis conditions in terms of solution and environmental parameters such as concentration of solvent, stoichiometry between ßCD and PFCs, temperature, pH, solvent type, etc. The best route of synthesis was then translated into various batch sizes and investigated in terms of the PFC loading and yield. These studies revealed that preparing NCCs in double-distilled water in an ice bath at the optimized solution concentration gave the highest yields and optimal PFC loading, as determined from gas chromatography. Furthermore, the stability of the clusters with different stoichiometries was scrutinized in varying concentrations, mechanical disruption times, pH levels, and temperature conditions, showing effects on each cluster's particle size in dynamic light scattering, visualized in transmission electron microscopy, and cavitation behavior in agarose gel tissue phantoms. These studies revealed stable clusters for all formulations, with PFH-containing NCCs emerging to be the most stable in terms of their cluster size and bubble formation potential in histotripsy. Finally, the shelf life of these clusters was investigated using DLS, which revealed a stable cluster. In conclusion, NCCs have shown high stability in terms of both synthesis, which can be replicated in gram-level production, and the cluster itself, which can be exposed to harsher conditions and still form stable bubbles in histotripsy.


Assuntos
Fluorocarbonos , Nanopartículas , beta-Ciclodextrinas , Fluorocarbonos/química , beta-Ciclodextrinas/química , Nanopartículas/química , Solventes/química , Temperatura , Concentração de Íons de Hidrogênio , Pentanos
8.
Biomacromolecules ; 25(1): 55-66, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-37878661

RESUMO

ß-Cyclodextrin (ß-CD) is often used as a drug carrier for biomedical materials due to its unique cavity structure. Herein, ß-CD was modified by acryloyl chloride and further copolymerized with N-isopropylacrylamide (NIPAM) and acrylic acid (AA) to obtain PNIPAM-co-ß-CD-AC. The results showed that the critical phase transition temperature of PNIPAM/ß-CD-AC could be controlled at 19 °C, and the fast sol-gel phase transition was realized in 2-10 s. The hydrophobic drug carried in this hydrogel can constantly be released for more than 6 days at pH values (pH 5.5-8), and the duration may match the recovery of the wound. As a dressing hydrogel, its rapid gel formation and inversion as well as shear-thinning behavior prevent secondary wound damage. The ß-CD-based hydrogel also has good biocompatibility and antioxidant properties, which provide a good potential choice for wound dressings, especially for exposed wounds in winter.


Assuntos
Hidrogéis , beta-Ciclodextrinas , Hidrogéis/química , Temperatura , beta-Ciclodextrinas/química , Temperatura Baixa , Bandagens
9.
Biomacromolecules ; 25(5): 2980-2989, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38587905

RESUMO

We developed a supramolecular system for codelivery of doxorubicin (Dox) and p53 gene based on a ß-CD-containing star-shaped cationic polymer. First, a star-shaped cationic polymer consisting of a ß-CD core and 3 arms of oligoethylenimine (OEI), named CD-OEI, was used to form a supramolecular inclusion complex with hydrophobic Dox. The CD-OEI/Dox complex was subsequently used to condense plasmid DNA via electrostatic interactions to form CD-OEI/Dox/DNA polyplex nanoparticles with positive surface charges that enhanced the cellular uptake of both Dox and DNA. This supramolecular drug and gene codelivery system showed high gene transfection efficiency and effective protein expression in cancer cells. The codelivery of Dox and DNA encoding the p53 gene resulted in reduced cell viability and enhanced antitumor effects at low Dox concentrations. With its enhanced cellular uptake and anticancer efficacy, the system holds promise as a delivery carrier for potential combination cancer therapies.


Assuntos
Doxorrubicina , Nanopartículas , Eletricidade Estática , Proteína Supressora de Tumor p53 , Humanos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administração & dosagem , beta-Ciclodextrinas/química , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Técnicas de Transferência de Genes , Nanopartículas/química , Proteína Supressora de Tumor p53/genética
10.
Biomacromolecules ; 25(6): 3685-3702, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38779908

RESUMO

Combination therapy has emerged as a promising approach for treating tumors, although there is room for improvement. This study introduced a novel strategy that combined the enhancement of apoptosis, ferroptosis, and DNA damage to improve therapeutic outcomes for prostate cancer. Specifically, we have developed a supramolecular oxidative stress nanoamplifier, which was comprised of ß-cyclodextrin, paclitaxel, and ferrocene-poly(ethylene glycol). Paclitaxel within the system disrupted microtubule dynamics, inducing G2/M phase arrest and apoptosis. Concurrently, ferrocene utilized hydrogen peroxide to generate toxic hydroxyl radicals in cells through the Fenton reaction, triggering a cascade of reactive oxygen species expansion, reduction of glutathione levels, lipid peroxidation, and ferroptosis. The increased number of hydroxyl radicals and the inhibitory effect of THZ531 on DNA repair mechanisms exacerbated DNA damage within tumor cells. As expected, the supramolecular nanoparticles demonstrated excellent drug delivery ability to tumor cells or tissues, exhibited favorable biological safety in vivo, and enhanced the killing effect on prostate cancer.


Assuntos
Estresse Oxidativo , Paclitaxel , Neoplasias da Próstata , Paclitaxel/farmacologia , Paclitaxel/química , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Animais , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Camundongos , Metalocenos/química , Nanopartículas/química , Apoptose/efeitos dos fármacos , Compostos Ferrosos/química , Compostos Ferrosos/farmacologia , Linhagem Celular Tumoral , beta-Ciclodextrinas/química , Polietilenoglicóis/química , Camundongos Nus , Ferroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Dano ao DNA/efeitos dos fármacos
11.
Soft Matter ; 20(21): 4291-4307, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38758097

RESUMO

Lipid asymmetry - that is, a nonuniform lipid distribution between the leaflets of a bilayer - is a ubiquitous feature of biomembranes and is implicated in several cellular phenomena. Differential tension - that is, unequal lateral monolayer tensions comparing the leaflets of a bilayer- is closely associated with lipid asymmetry underlying these varied roles. Because differential tension is not directly measurable in combination with the fact that common methods to adjust this quantity grant only semi-quantitative control over it, a detailed understanding of lipid asymmetry and differential tension are impeded. To overcome these challenges, we leveraged reversible complexation of phospholipid by methyl-ß-cyclodextrin (mbCD) to tune the direction and magnitude of lipid asymmetry in synthetic vesicles. Lipid asymmetry generated in our study induced (i) vesicle shape changes and (ii) gel-liquid phase coexistence in 1-component vesicles. By applying mass-action considerations to interpret our findings, we discuss how this approach provides access to phospholipid thermodynamic potentials in bilayers containing lipid asymmetry (which are coupled to the differential tension of a bilayer). Because lipid asymmetry yielded by our approach is (i) tunable and (ii) maintained over minute to hour timescales, we anticipate that this approach will be a valuable addition to the experimental toolbox for systematic investigation into the biophysical role(s) of lipid asymmetry (and differential tension).


Assuntos
Bicamadas Lipídicas , Fosfolipídeos , beta-Ciclodextrinas , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , beta-Ciclodextrinas/química , Fosfolipídeos/química , Termodinâmica
12.
Analyst ; 149(9): 2647-2654, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38546701

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are durable synthetic pollutants that persist in the environment and resist biodegradation. Ion-transfer electrochemistry at aqueous-organic interfaces is a simple strategy for the detection of ionised PFAS. Herein, we investigate the modulation of the ion transfer voltammetry of perfluorooctanoate (PFOA) at liquid-liquid micro-interface arrays by aqueous phase bovine serum albumin (BSA) or ß-cyclodextrin (ß-CD) and examine the determination of association constants for these binding interactions. By tracking the ion transfer current due to ionised, uncomplexed PFOA as a function of BSA or ß-CD concentration, titration curves are produced. Fitting of a binding isotherm to these data provides the association constants. The association constant of PFOA with the BSA determined in this way was ca. 105 M-1 assuming a 1 : 1 binding. Likewise, the association constant for PFOA with ß-CD was ca. 104 M-1 for a 1 : 1 ß-CD-PFOA complex. Finally, the simultaneous effect of both BSA and ß-CD on the ion transfer voltammetry of PFOA was studied, showing clearly that PFOA bound to BSA is released (de-complexed) upon addition of ß-CD. The results presented here show ion transfer voltammetry as a simple strategy for the study of molecular and biomolecular binding of ionised PFAS and is potentially useful in understanding the affinity of different PFAS with aqueous phase binding agents such as proteins and carbohydrates.


Assuntos
Caprilatos , Fluorocarbonos , Soroalbumina Bovina , beta-Ciclodextrinas , Fluorocarbonos/química , beta-Ciclodextrinas/química , Caprilatos/química , Soroalbumina Bovina/química , Bovinos , Animais , Técnicas Eletroquímicas/métodos , Eletroquímica
13.
J Chem Inf Model ; 64(9): 3865-3873, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38598310

RESUMO

Previous experimental studies have shown that the isomerization reaction of previtamin D3 (PreD3) to vitamin D3 (VitD3) is accelerated 40-fold when it takes place within a ß-cyclodextrin dimer, in comparison to the reaction occurring in conventional isotropic solutions. In this study, we employ quantum mechanics-based molecular dynamics (MD) simulations and statistical multistructural variational transition state theory to unveil the origin of this acceleration. We find that the conformational landscape in the PreD3 isomerization is highly dependent on whether the system is encapsulated. In isotropic media, the triene moiety of the PreD3 exhibits a rich torsional flexibility. However, when encapsulated, such a flexibility is limited to a more confined conformational space. In both scenarios, our calculated rate constants are in close agreement with experimental results and allow us to identify the PreD3 flexibility restriction as the primary catalytic factor. These findings enhance our understanding of VitD3 isomerization and underscore the significance of MD and environmental factors in biochemical modeling.


Assuntos
Simulação de Dinâmica Molecular , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Catálise , Isomerismo , Vitamina D/química , Vitamina D/metabolismo , Teoria Quântica , Conformação Molecular , Colecalciferol/química , Colecalciferol/metabolismo
14.
Anal Bioanal Chem ; 416(8): 1951-1959, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38324071

RESUMO

To conveniently monitor bioactive cysteine (Cys) and Fe2+ in practice, a kind of poly-ß-cyclodextrin strengthen praseodymium oxide (Pr6O11) porous oxidase mimic (p-ß-CD@Pr6O11) was constructed by virtue of the strong coordination between nano Pr6O11 and poly-ß-cyclodextrin substrate. After its microstructure and physicochemical property were characterized in detail, it was noted that porous p-ß-CD@Pr6O11 exhibited excellent enzyme-like catalytic activity to accelerate the oxidation of 3,3',5,5,'-tetramethylbanzidine (TMB) and 2,2'-azinobis (3-ethylbenzo-thiazoline-6-sulfonic acid) ammonium salt (ABTS) with significant color-enhancement effect in the air. Based on the signal amplification, trace Cys could exclusively deteriorate the UV-vis absorbance at 653 nm of p-ß-CD@Pr6O11-TMB and Fe2+ alter the one at 729 nm of p-ß-CD@Pr6O11-ABTS with visual color changes. Under the optimized conditions, the proposed p-ß-CD@Pr6O11-TMB and p-ß-CD@Pr6O11-ABTS systems were successfully applied for dual-channel monitoring of Cys in Cys capsules and fetal bovine serum and Fe2+ in agricultural products with quite low detection limits, i.e., 7.8×10-9 mol·L-1 for Cys and 6.93×10-8 mol·L-1 (S/N=3) for Fe2+, respectively. The synergetic-enhancement detection mechanisms to Cys and Fe2+ were also proposed.


Assuntos
Benzotiazóis , Oxirredutases , Ácidos Sulfônicos , beta-Ciclodextrinas , Cisteína/química , Porosidade , beta-Ciclodextrinas/química , Colorimetria
15.
J Appl Microbiol ; 135(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38744659

RESUMO

AIM: This study investigated the effectiveness of a drug-modified tissue conditioner in an animal model of denture stomatitis. METHODS AND RESULTS: Wistar rats wore a Candida albicans-contaminated palatal device for 4 days. Next, nystatin (Nys) or chlorhexidine (Chx) were added to a tissue conditioner in their raw or ß-cyclodextrin-complexed (ßCD) forms at their minimum inhibitory concentrations. As controls, one group was not subjected to any procedure (NC), one group used sterile devices, one group had denture stomatitis but was not treated (DS), and another had the devices relined with the tissue conditioner without the addition of any drug (Soft). After 4 days of treatment, treatment effectiveness was assessed visually, histologically, and through CFU count, and myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) assays. Rats from the Soft, Nys, Nys:ßCD, and Chx groups presented a significant decrease in the microbial load compared with the untreated group. Treatment groups showed lower MPO and NAG activity compared to the non-treated group. CONCLUSIONS: The addition of antifungals to a soft tissue conditioner can be a promising approach for denture stomatitis treatment.


Assuntos
Antifúngicos , Candida albicans , Clorexidina , Nistatina , Ratos Wistar , Estomatite sob Prótese , Animais , Estomatite sob Prótese/microbiologia , Estomatite sob Prótese/tratamento farmacológico , Ratos , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Nistatina/farmacologia , Nistatina/uso terapêutico , Clorexidina/farmacologia , Candida albicans/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Peroxidase/metabolismo , Acetilglucosaminidase/metabolismo , beta-Ciclodextrinas
16.
Environ Res ; 243: 117868, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38072113

RESUMO

In the present study, ß-cyclodextrin modified magnetic graphene oxide/cellulose (CN/IGO/Cel) was fabricated for removal of Cd(II) ions. The material was characterized through various analytical techniques like FTIR, XRD, TGA/DTA, SEM, TEM, and XPS. The point of zero charge of the material was obtained as 5.38. The controllable factors were optimized by Taguchi design and optimum values were: adsorbent dose-16 mg, equilibrium time-40 min, and initial concentration of Cd(II) ions-40 mg/L. The material shows high adsorption capacity (303.98 mg/g). The good fitting of Langmuir model to adsorption data (R2 = 0.9918-0.9936) revealed the monolayer coverage on adsorbent surface. Statistical physics model M 2 showed best fitting to adsorption data (R2 > 0.997), suggesting the binding of Cd(II) ions occurred on two different receptor sites (n). Stereographically n > 1 confirming vertical multi-molecular mechanisms of Cd(II) ions adsorption on CN/IGO/Cel surface. The adsorption energies (E1 = 23.71-28.95 kJ/mol; E2 = 22.69-29.38 kJ/mol) concluded the involvement of physical forces for Cd(II) ions adsorption. Kinetic data fitted well to fractal-like pseudo first-order model (R2 > 0.9952), concluding the adsorption of Cd(II) ions occurred on energetically heterogeneous surface. The kinetic analysis shows that both the film-diffusion and pore-diffusion were responsible for Cd(II) ions uptake. XPS analysis was utilized to explain the adsorption mechanism of Cd(II) ions onto CN/IGO/Cel.


Assuntos
Grafite , Poluentes Químicos da Água , beta-Ciclodextrinas , Cádmio/análise , Adsorção , Fractais , Celulose , Cinética , Magnetismo , Fenômenos Magnéticos , beta-Ciclodextrinas/análise , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
17.
BMC Vet Res ; 20(1): 214, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769544

RESUMO

As an orally effective benzimidazole anthelmintic agent, fenbendazole was not only widely used in agriculture and animal husbandry to prevent and treat parasites, but also shows anti-cancer effects against several types of cancer, exhibits anti-cancer effects in paclitaxel and doxorubicin-resistant cancer cells. However, fenbendazole's poor in water solubility (0.3 µg/mL), limits its clinical applications. Even great efforts were made toward increasing its water solubility, the results were not significant to reach anti-cancer drug delivery requirement (5-10 mg/mL). Through single factor and orthogonal strategy, many complex conditions were designed and used to prepare the complexes, the inclusion complex with methyl-ß-cyclodextrin with 29.2 % of inclusion rate and 89.5% of inclusion yield can increase drug's water solubility to 20.21 mg/mL, which is the best result so far. Its structure was confirmed by differential scanning calorimetry, scanning electron microscopic image, 1D and 2D NMR spectra in D2O. In its in vitro pharmacokinetic study, fenbendazole was 75% released in 15 min., in its in vivo pharmacokinetic study, the bio-availabilities of fenbendazole, its major metabolic anthelmintic agent oxfendazole and its minor metabolic anthelmintic agent oxfendazole were increased to 138%, 149% and 169% respectively, which would allow for fewer drug doses to achieve the same therapeutic effect and suggest that the complex can be used as a potential anticancer agent.


Assuntos
Fenbendazol , Solubilidade , beta-Ciclodextrinas , Fenbendazol/farmacocinética , Fenbendazol/uso terapêutico , Fenbendazol/química , Animais , beta-Ciclodextrinas/química , Antineoplásicos/farmacocinética , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Masculino , Anti-Helmínticos/farmacocinética , Anti-Helmínticos/química , Anti-Helmínticos/administração & dosagem
18.
Chirality ; 36(5): e23672, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693625

RESUMO

Hydroxychloroquine (HCQ), 2-([4-([7-Chloro-4-quinolyl]amino)pentyl]ethylamino)ethanol, exhibited significant biological activity, while its side effects cannot be overlooked. The RP-HPLC enantio-separation was investigated for cost-effective and convenient optical purity analysis of HCQ. The thermodynamic resolution of Rac-HCQ, driven by enthalpy and entropy, was achieved on the C18 column using Carboxymethyl-ß-cyclodextrin (CM-ß-CD) as the chiral mobile phase agent (CMPA). The effects of CCM-ß-CD, pH, and triethylamine (TEA) V% on the enantio-separation process were explored. Under the optimum conditions at 24°C, the retention times for the two enantiomers were t R 1 = 29.39 min $$ {t}_{R1}=29.39\ \min $$ and t R 2 = 32.42 min $$ {t}_{R2}=32.42\ \min $$ , resulting in R s = 1.87 $$ {R}_s=1.87 $$ . The resolution via diastereomeric salt formation of Rac-HCQ was developed to obtain the active pharmaceutical ingredient of single enantiomer S-HCQ. Di-p-Anisoyl-L-Tartaric Acid (L-DATA) was proved effective as the resolution agent for Rac-HCQ. Surprisingly, it was found that refluxing time was a key fact affecting the resolution efficiency, which meant the kinetic dominate during the process of the resolution. Four factors-solvent volume, refluxing time, filtration temperature, and molar ratio-were optimized using the single-factor method and the response surface method. Two cubic models were established, and the reliability was subsequently verified. Under the optimal conditions, the less soluble salt of 2L-DATA:S-HCQ was obtained with a yield of 96.9% and optical purity of 63.0%. The optical purity of this less soluble salt increases to 99.0% with a yield of 74.2% after three rounds recrystallization.


Assuntos
Hidroxicloroquina , Hidroxicloroquina/química , Estereoisomerismo , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , beta-Ciclodextrinas/química , Cromatografia de Fase Reversa/métodos , Etilaminas/química , Termodinâmica , Sais/química
19.
J Sep Sci ; 47(12): e2400190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38894562

RESUMO

An efficient method for the continuous separation of Voriconazole enantiomers was developed using sulfobutyl ether-ß-cyclodextrin (SBE-ß-CD) as a chiral selector in high-speed countercurrent chromatography (HSCCC) with different types. The separation was performed using a two-phase solvent system consisting of n-hexane/ethyl acetate/100 mmol/L phosphate buffer solution (pH = 3.0, containing 50 mmol/L SBE-ß-CD) (1.5:0.5:2, v/v/v). A fast and predictable scale-up process was achieved using an analytical DE HSCCC instrument. The optimized parameters were subsequently applied to a preparative Tauto HSCCC instrument, resulting in consistent separation time and enantiomeric purity, with throughput boosted by a remarkable 11-fold. Preparative HSCCC successfully separated 506 mg of the racemate, delivering enantiomers exceeding 99% purity as confirmed by high-performance liquid chromatography analysis. This investigation presents an effective methodology for forecasting the HSCCC scale-up process and attaining continuous separation of chiral drugs.


Assuntos
Distribuição Contracorrente , Voriconazol , Distribuição Contracorrente/métodos , Estereoisomerismo , Voriconazol/química , Voriconazol/isolamento & purificação , Cromatografia Líquida de Alta Pressão , beta-Ciclodextrinas/química
20.
Biosci Biotechnol Biochem ; 88(6): 601-607, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38569654

RESUMO

Lipoic acid trisulfide, a sulfane sulfur-containing trisulfide of α-lipoic acid, holds promise in pharmaceuticals, yet knowledge gaps persist regarding its synthesis, properties, and stability. Here, we synthesized the lipoic acid trisulfide with a purity exceeding 99% from α-lipoic acid on a gram scale and obtained novel ß-cyclodextrin clathrates (84%-95% yield). Differential scanning calorimetry confirmed the inclusion of lipoic acid trisulfide in ß-cyclodextrins. The resulting ß-cyclodextrin clathrates exhibited significant improvements in water solubility and thermal stability. This pioneering study demonstrated a novel approach to the practical preparation of trisulfide and its ß-cyclodextrin clathrates as active ingredients, paving the way for clinical development.


Assuntos
Solubilidade , Ácido Tióctico , beta-Ciclodextrinas , Ácido Tióctico/química , beta-Ciclodextrinas/química , Sulfetos/química , Varredura Diferencial de Calorimetria , Estabilidade de Medicamentos , Água/química
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