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1.
Chem Commun (Camb) ; 55(58): 8434-8437, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31259350

RESUMO

Phosphatidylcholine is the main component of liposomes and other phospholipid-based nanocarriers in drug delivery. However, the functions and applications of these nanocarriers are extremely limited by conventional phospholipids. Here we report novel disulfide phosphatidylcholines (SS-PCs) and SS-PC based liposomes (SS-LPs) used as alternatives to traditional phospholipids and liposomes.


Assuntos
Dissulfetos/química , Portadores de Fármacos/química , Lipossomos/química , Fosfatidilcolinas/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Dissulfetos/síntese química , Dissulfetos/metabolismo , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Humanos , Lipossomos/síntese química , Lipossomos/metabolismo , Camundongos , Oxirredução , Fosfatidilcolinas/síntese química , Fosfatidilcolinas/metabolismo
2.
Chem Commun (Camb) ; 55(65): 9653-9656, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31342021

RESUMO

The fast and accurate real-time monitoring of hydrogen peroxide (H2O2) secreted from living cells plays a critical role in clinical diagnosis and management. Herein, we report low-cost and self-supported MoS2 nanosheet arrays for non-enzymatic eletrochemical H2O2 detection. Under the optimal test conditions, such MoS2 electrodes exhibit extremely promising electrocatalytic performance with a low detection limit of 1.0 µM (S/N = 3) and an excellent sensitivity of 5.3 mA mM-1 cm-2. Furthermore, the detection of the trace amount of H2O2 secreted from live A549 cancer cells was successfully performed with this biosensor.


Assuntos
Dissulfetos/química , Peróxido de Hidrogênio/análise , Molibdênio/química , Nanoestruturas/química , Células A549 , Técnicas Biossensoriais/métodos , Carbono/química , Dissulfetos/síntese química , Técnicas Eletroquímicas/métodos , Humanos , Limite de Detecção
3.
J Agric Food Chem ; 67(31): 8559-8572, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298518

RESUMO

Avenin-like b protein is rich in cysteine residues, providing the possibility to form intermolecular disulfide bonds and then participate in glutenin polymerization. Site-directed mutagenesis was adopted to produce mutant avenin-like b gene encoding mutant avenin-like b protein, in which one tyrosine codon at the C-terminal is substituted by a cysteine codon. Compared with the control lines, both transgenic lines with wild-type and mutant avenin-like b genes demonstrated superior dough properties. While compared within the transgenic lines, the mutant lines showed relative weaker dough strength and decreased sodium-dodecyl-sulfate sedimentation volumes (from 69.7 mL in line WT alb-1 to 41.0 mL in line Mut alb-4). These inferior dough properties were accompanied by the lower contents of large-sized glutenin polymers, the decreased particle diameters of glutenin macropolymer (GMP), due to the lower content of intermolecular ß-sheets (from 39.48% for line WT alb-2 to 30.21% for line Mut alb-3) and the varied contents of disulfide bonds (from 137.37 µmol/g for line WT alb-1 to 105.49 µmol/g for line Mut alb-4) in wheat dough. The extra cysteine might alter the original disulfide bond structure, allowing cysteine residue usually involved in an intermolecular disulfide bond to become available for an intrachain disulfide bond. Avenin-like b proteins were detected in glutenin macropolymers, providing further evidence for this protein to participate in the polymerization of glutenin. This is the first time to investigate the effect of a specific cysteine residue in the avenin-like b protein on flour quality.


Assuntos
Cisteína/genética , Farinha/análise , Plantas Geneticamente Modificadas/genética , Prolaminas/genética , Triticum/genética , Pão/análise , Cisteína/metabolismo , Dissulfetos/química , Manipulação de Alimentos , Mutagênese Sítio-Dirigida , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/metabolismo , Prolaminas/metabolismo , Triticum/química , Triticum/metabolismo
4.
Chem Soc Rev ; 48(16): 4361-4374, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31294429

RESUMO

Antibody-Drug Conjugates (ADCs) are now established as a major class of therapeutics for the clinical treatment of cancer. The properties of the linker between the antibody and the payload are proven to be critical to the success of an ADC. Although ADC linkers can be 'non-cleavable', the vast majority of ADCs in clinical development have specific release mechanisms to allow controlled linker cleavage at the target site and are thus termed 'cleavable'. In recent years, the development of new methods of drug release from ADCs has continued in parallel to the deepening understanding of the biological processes underlying the mechanisms of action of pre-existing technologies. This review summarises the advances in the field of cleavable linker technologies for ADCs.


Assuntos
Anticorpos Monoclonais/química , Imunoconjugados/química , Ácidos/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Catepsina B/metabolismo , Dissulfetos/química , Estabilidade de Medicamentos , Humanos , Imunoconjugados/sangue , Imunoconjugados/metabolismo
5.
J Nanobiotechnology ; 17(1): 78, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269964

RESUMO

BACKGROUND: The construction of a multifunctional drug delivery system with a variety of advantageous features, including targeted delivery, controlled release and combined therapy, is highly attractive but remains a challenge. RESULTS: In this study, we developed a MoS2-based hyaluronic acid (HA)-functionalized nanoplatform capable of achieving targeted delivery of camptothecin (CPT) and dual-stimuli-responsive drug release. HA was connected to MoS2 via a disulfide linkage, forming a sheddable HA shell on the surface of MoS2. This unique design not only effectively prevented the encapsulated CPT from randomly leaking during blood circulation but also significantly accelerated the drug release in response to tumor-associated glutathione (GSH). Moreover, the MoS2-based generated heat upon near-infrared (NIR) irradiation could further increase the drug release rate as well as induce photothermal ablation of cancer cells. The results of in vitro and in vivo experiments revealed that MoS2-SS-HA-CPT effectively suppressed cell proliferation and inhibited tumor growth in lung cancer cell-bearing mice under NIR irradiation via synergetic chemo-photothermal therapy. CONCLUSIONS: The as-prepared MoS2-SS-HA-CPT with high targeting ability, dual-stimuli-responsive drug release, and synergistic chemo-photothermal therapy may provide a new strategy for cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Dissulfetos/química , Portadores de Fármacos/química , Molibdênio/química , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Liberação Controlada de Fármacos , Feminino , Corantes Fluorescentes/química , Humanos , Ácido Hialurônico/química , Hipertermia Induzida , Raios Infravermelhos , Camundongos Nus , Transplante de Neoplasias , Oxirredução , Fotoquimioterapia/métodos
6.
Talanta ; 202: 342-348, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171193

RESUMO

A molecular beacons (MBs) loaded on molybdenum disulfide (MoS2) nanosheets as fluorescence probes for sensitive and versatile detection of microRNAs (miRNAs) through hybridization chain reaction (HCR) has been designed. MoS2 was used as a adsorbent to capture the MBs and a selective fluorescence quencher to reduce the background signal. In the absence of miRNAs, HCR could not be triggered due to the stability of MB probes. The probes attached to the MoS2 surface, efficiently quenching fluorescence of the G-quadruplex/Thioflavin T. However, the presence of target miRNAs triggers the HCR process to generate large amount of HCR products. Meanwhile, the HCR products of long nanowires chain with abundant G-quadruplexes could not be adsorbed on the surface of MoS2, and therefore detach from the MoS2. Consequently, Thioflavin T could be embedded in G-quadruplexes and produced strong fluorescence signal. This fluorescence emission signal could achieve detection of miRNA as low as 4.2 pM and a wide linear ranges from 0.1 to 100 nM. In addition, a versatile fluorescence probe has been developed for detection of miRNA-21 by changing the miRNA-recognition domain of MB. Thus, the fluorescent probe would be a potential alternative tool for biomedical research and clinical molecular diagnostics.


Assuntos
Dissulfetos/química , Corantes Fluorescentes/química , Quadruplex G , MicroRNAs/análise , Sondas Moleculares/química , Molibdênio/química , Hibridização de Ácido Nucleico , Humanos
7.
Forensic Sci Int ; 301: 149-159, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31153992

RESUMO

This case report summarises the investigation of a death scene in the trunk of a car. Air sampling, laser-induced breakdown spectroscopy, and gas chromatography/mass spectrometry on samples of carpet and tyre well scrapings from the vehicle's trunk were utilised to confirm the presence of a human decompositional event even though no human remains were discovered in the vehicle. Air sampling has been used in numerous industries for many decades, but only recently has been applied to forensic investigations although it has been at the centre of controversy over the use of this technique in such cases. This report also describes the value of such investigative tools and points to the discovery of evidence, which, without the use of these techniques, would not have been identified.


Assuntos
Poluentes Atmosféricos/análise , Odorantes , Mudanças Depois da Morte , Automóveis , Dissulfeto de Carbono/análise , Tetracloreto de Carbono/análise , Clorofórmio/análise , Dissulfetos/análise , Elementos , Ácidos Graxos Voláteis/análise , Feminino , Pisos e Cobertura de Pisos , Ciências Forenses/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lasers , Análise Espectral , Sulfetos/análise
8.
Chem Commun (Camb) ; 55(52): 7510-7513, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31187817

RESUMO

Self-assembly of protein nanocages into two-dimensional superlattices can be achieved by disulfide-mediated modular interactions, which can be carried out by introducing single point mutation on the exterior surfaces of the protein nanocages nearby the symmetry rotation axes. As designed, the protein cages arrange in an on-axis alignment pattern.


Assuntos
Dissulfetos/química , Nanoestruturas/química , Proteínas/metabolismo , Cisteína/química , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Oxirredução , Mutação Puntual , Proteínas/genética
9.
Chem Commun (Camb) ; 55(60): 8772-8775, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31172998

RESUMO

We introduced a new concept to the control of wetting characteristics by modulating the degree of atomic defects of two-dimensional transition metal dichalcogenide nanoassemblies of molybdenum disulfide. This work shed new light on the role of atomic vacancies on wetting characteristic that can be leveraged to develop a new class of superhydrophobic surfaces for various applications without altering their topography.


Assuntos
Adesão Celular , Dissulfetos/química , Células-Tronco Mesenquimais/fisiologia , Molibdênio/química , Nanoestruturas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Molhabilidade
10.
Food Chem ; 297: 125005, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253325

RESUMO

Multiwalled carbon nanotubes molybdenum disulfide 3D nanocomposite (MWCNT-MoS2 NC) was successfully synthesized via eco-friendly hydrothermal method. The microstructural characterization of synthesized nanocomposite was carried out using different spectroscopic and microscopic techniques. Nanocomposite was activated using glutaraldehyde chemistry and used as a platform to immobilize Lens culinaris ß-galactosidase (Lsbgal) which resulted in 93% of immobilization efficiency. Attachment of Lsbgal onto nanocomposite was confirmed by AFM, FE-SEM, FTIR, and CLSM. The nanobiocatalyst showed broadening in operational pH and temperature working range. Remarkable increase in thermal stability was observed as compared to soluble enzyme. Nanobiocatalyst showed outstanding increase in storage stability, retained 92% of residual activity over a period of 8 months. This offers good reusability as it retained ∼50% residual activity up to 21 reuses and exhibited higher rate of lactose hydrolysis in whey. MWCNT-MoS2 NC conjugated to biomolecules can serve as a potential platform for fabrication of lactose biosensor.


Assuntos
Lactose/metabolismo , Lens (Planta)/enzimologia , Nanocompostos/química , Soro do Leite/metabolismo , beta-Galactosidase/metabolismo , Biocatálise , Dissulfetos/química , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Molibdênio/química , Nanotubos de Carbono/química , Temperatura Ambiente , beta-Galactosidase/química
11.
Int J Nanomedicine ; 14: 3893-3909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239663

RESUMO

Background: Photothermal and chemotherapy treatment has been frequently studied for cancer therapy; however, chemotherapy is equally toxic to both normal and cancer cells. The clinical application value of most kinds of photothermal transforming agents remains limited, due to their poor degradation and minimal accumulation in tumors. Materials and methods: We reported the synthesis of photothermal transforming agents (MoS2) and chemotherapeutic (doxorubicin, DOX) co-loaded electrospun nanofibers using blend electrospinning for the treatment of postoperative tumor recurrence. Results: Under the irradiation of an 808 nm laser, the as-prepared chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an admirable photothermal conversion capability with a photothermal conversion efficiency of 23.2%. These composite nanofibers are in vitro and in vivo biocompatible. In addition, they could control the sustained release of DOX and the generated heat can sensitize the chemotherapeutic efficacy of DOX via enhancing its release rate. Their chemo-/photothermal combined therapy efficiency was systematically studied in vitro and in vivo. Instead of circulating with the body fluid, MoS2 was trapped by the nanofibrous matrix in the tumor and so its tumor-killing ability was not compromised, thus rendering this composite nanofiber a promising alternative for future clinical translation within biomedical application fields. Conclusion: Chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an excellent photothermal conversion capability with a photothermal conversion efficiency of 23.2% and can completely inhibit the postoperative tumor reoccurrence.


Assuntos
Dissulfetos/química , Doxorrubicina/uso terapêutico , Molibdênio/química , Nanofibras/química , Nanotecnologia/métodos , Neoplasias/terapia , Fototerapia , Animais , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HT29 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanofibras/ultraestrutura , Recidiva Local de Neoplasia/patologia , Neoplasias/sangue , Neoplasias/patologia , Neoplasias/cirurgia , Padrões de Referência , Resultado do Tratamento
12.
Food Chem ; 296: 9-16, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31202311

RESUMO

Z-lycopene isomers are more bioavailable than all-E-lycopene, especially 5-Z-lycopene. Based on our observations, the addition of unblanched onion could favor Z-isomerization of lycopene (by more than 94%) during heating tomato-onion-extra virgin olive oil (EVOO) purees at 90 °C for 2 h. The increase in Z-lycopene was correlated linearly with the addition of unblanched onion, with R2 > 0.92, and increased rates of 5-Z-lycopene were 3-4 times higher than for 9-Z-lycopene and 13-Z-lycopene. Diallyl disulfide (DADS), formed by alliinase-catalyzed breakdown of non-volatile precursors in onion, contributed to these increases and correlated linearly (R2 > 0.79, 0-0.50 mg/g puree) with increased Z-lycopene. Increased rates of 5-Z-lycopene were also 3-4 times higher than for 9-Z-lycopene and 13-Z-lycopene. However, blanching of onion, in tomato-onion-EVOO purees, before heating, significantly decreased the effect of onion on Z-isomerization of lycopene.


Assuntos
Lipídeos/química , Licopeno/química , Lycopersicon esculentum/química , Cebolas/química , Compostos Alílicos/química , Cromatografia Líquida de Alta Pressão , Dissulfetos/química , Isomerismo , Licopeno/análise , Lycopersicon esculentum/metabolismo , Azeite de Oliva/química , Cebolas/metabolismo , Temperatura Ambiente
13.
Nat Commun ; 10(1): 2745, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227705

RESUMO

Small molecule probes are indispensable tools to explore diverse cellular events. However, finding a specific probe of a target remains a high challenge. Here we report the discovery of Fast-TRFS, a specific and superfast fluorogenic probe of mammalian thioredoxin reductase, a ubiquitous enzyme involved in regulation of diverse cellular redox signaling pathways. By systematically examining the processes of fluorophore release and reduction of cyclic disulfides/diselenides by the enzyme, structural factors that determine the response rate and specificity of the probe are disclosed. Mechanistic studies reveal that the fluorescence signal is switched on by a simple reduction of the disulfide bond within the probe, which is in stark contrast to the sensing mechanism of published probes. The favorable properties of Fast-TRFS enable development of a high-throughput screening assay to discover inhibitors of thioredoxin reductase by using crude tissue extracts as a source of the enzyme.


Assuntos
Descoberta de Drogas/métodos , Corantes Fluorescentes/química , Imagem Molecular/métodos , Sondas Moleculares/química , Tiorredoxina Redutase 1/metabolismo , Animais , Produtos Biológicos/farmacologia , Misturas Complexas , Dissulfetos/química , Corantes Fluorescentes/metabolismo , Células HeLa , Ensaios de Triagem em Larga Escala/métodos , Humanos , Microscopia Intravital/métodos , Microscopia de Fluorescência/métodos , Sondas Moleculares/metabolismo , Oxirredução , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Tiorredoxina Redutase 1/antagonistas & inibidores , Tiorredoxina Redutase 1/genética
14.
Chemosphere ; 232: 9-17, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31152908

RESUMO

Amorphous molybdenum sulphide materials are attracting more attention in heterogeneous catalysis, gas adsorption and water remediation fields. Herein, a new type of amorphous molybdenum sulphide composite (poly(diallyldimethylammonium-MoS4), shorten as PDADMA-MoS4) was synthesized via a facile precipitation reaction. Metal adsorption tests of prepared PDADMA-MoS4 composite shows that Hg2+ and Pb2+ concentrations in solution can decrease from 10 ppm to <0.5 ppb level much lower than the drinking water requirement (<2 ppb) in 10 min. The metal adsorption isotherms suggest that maximum metal-uptake capacities are 1460.0 mg/g for Hg (pH = 5) and 433.7 mg/g for Hg (pH = 1), indicating that this sorbent works over a wide pH range (1.0-7.0) to effectively remove Hg from aqueous solution. More importantly, at very low pH = 1, this sorbent material exhibits extraordinarily high selectivity of Hg over Pb and Cu (separation factors ßHg/Cu=4.5×104 and ßHg/Pb=3.6×104). The excellent Hg capacity and selectivity at low pH region (pH < 2) has shed light on the new generation of adsorbent materials for acidic wastewater treatment.


Assuntos
Dissulfetos/química , Mercúrio/análise , Molibdênio/química , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Adsorção , Concentração de Íons de Hidrogênio , Metais
15.
Anal Bioanal Chem ; 411(21): 5481-5488, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31236648

RESUMO

The mechanism behind the variation in the photoluminescence (PL) of a MoS2 nanohybrid material with pH was investigated. Highly fluorescent MoS2 quantum dots dispersed across MoS2 nanosheets (MoS2 QDNS) were synthesized by a hydrothermal route in the presence of NaOH. Upon reducing the pH from 13 to 6.5, the PL intensity was markedly quenched. The removal of dangling sulfur atoms by adding mineral acids could be a plausible mechanism for this PL quenching, together with the inner filter effect and Förster resonance energy transfer due to the resulting species. A label-free turn-on fluorescence sensor for H2O2 was developed using this hybrid material. The PL of the acidified MoS2 QDNS at pH 6.5 increased (i.e., recovered) linearly with the concentration of H2O2. The dynamic range of the sensor was found to be 2-94 µM with a limit of detection (LOD) of 2 µM. This sensing strategy was also extended for the detection of glucose by appending glucose oxidase (GOx) as a catalyst. In the presence of GOx, glucose oxidizes to gluconic acid and H2O2, so the original level of glucose can be estimated by determining the H2O2 present. The absence of a complicated enzyme immobilization step is the prime advantage of the present glucose sensor. The current work exemplifies the utility of MoS2-based nanoparticle systems in the biological sensor domain. Graphical abstract.


Assuntos
Dissulfetos/química , Peróxido de Hidrogênio/análise , Concentração de Íons de Hidrogênio , Molibdênio/química , Transferência Ressonante de Energia de Fluorescência , Glucose Oxidase/análise , Limite de Detecção , Medições Luminescentes
16.
J Nanobiotechnology ; 17(1): 76, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217009

RESUMO

BACKGROUND: Molybdenum disulfide (MoS2) has been widely explored for biomedical applications due to its brilliant photothermal conversion ability. In this paper, we report a novel multifunctional MoS2-based drug delivery system (MoS2-SS-HA). By decorating MoS2 nanosheets with hyaluronic acid (HA), these functionalized MoS2 nanosheets have been developed as a tumor-targeting chemotherapeutic nanocarrier for near-infrared (NIR) photothermal-triggered drug delivery, facilitating the combination of chemotherapy and photothermal therapy into one system for cancer therapy. RESULTS: The nanocomposites (MoS2-SS-HA) generated a uniform diameter (ca. 125 nm), exhibited great biocompatibility as well as high stability in physiological solutions, and could be loaded with the insoluble anti-cancer drug erlotinib (Er). The release of Er was greatly accelerated under near infrared laser (NIR) irradiation, showing that the composites can be used as responsive systems, with Er release controllable through NIR irradiation. MTT assays and confocal imaging results showed that the MoS2-based nanoplatform could selectively target and kill CD44-positive lung cancer cells, especially drug resistant cells (A549 and H1975). In vivo tumor ablation studies prove a better synergistic therapeutic effect of the joint treatment, compared with either chemotherapy or photothermal therapy alone. CONCLUSION: The functionalized MoS2 nanoplatform developed in this work could be a potent system for targeted drug delivery and synergistic chemo-photothermal cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Dissulfetos/química , Portadores de Fármacos/química , Cloridrato de Erlotinib/farmacologia , Hipertermia Induzida , Molibdênio/química , Nanocompostos/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Cloridrato de Erlotinib/química , Feminino , Humanos , Ácido Hialurônico/química , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fototerapia
17.
J Nanobiotechnology ; 17(1): 77, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226993

RESUMO

BACKGROUND: The design of efficient drug delivery vectors requires versatile formulations able to simultaneously direct a multitude of molecular targets and to bypass the endosomal recycling pathway of cells. Liposomal-based vectors need the decoration of the lipid surface with specific peptides to fulfill the functional requirements. The unspecific binding of peptides to the lipid surface is often accompanied with uncontrolled formulations and thus preventing the molecular mechanisms of a successful therapy. RESULTS: We present a simple synthesis pathway to anchor cysteine-terminal peptides to thiol-reactive lipids for adequate and quantitative liposomal formulations. As a proof of concept, we have synthesized two different lipopeptides based on (a) the truncated Fibroblast Growth Factor (tbFGF) for cell targeting and (b) the pH sensitive and fusogenic GALA peptide for endosomal scape. CONCLUSIONS: The incorporation of these two lipopeptides in the liposomal formulation improves the fibroblast cell targeting and promotes the direct delivery of cargo molecules to the cytoplasm of the cell.


Assuntos
Dissulfetos/química , Lipídeos/química , Peptídeos/química , Piridinas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Cisteína/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lipossomos/química , Camundongos , Estrutura Molecular , Imagem Óptica/métodos , Estudo de Prova de Conceito
18.
Dis Aquat Organ ; 135(1): 59-70, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31244485

RESUMO

Gamma-interferon-inducible lysosomal thiol reductase (GILT) is involved in the adaptive immune response via its effects on major histocompatibility complex (MHC)-restricted antigen presentation. In addition to antigen presentation, GILT exerts its antiviral activity by reducing disulfide bonds in proteins involved in viral infection and assembly, thereby inhibiting viral envelope-mediated infection and viral progeny production. In black tiger shrimp, Penaeus monodon GILT (PmGILT) was cloned and characterized, and found to be involved in the shrimp innate immune response and to exert neutralizing activity against white spot syndrome virus (WSSV) infection. However, the anti-WSSV mechanism of PmGILT in the shrimp innate immune response has not been defined. To explore the anti-WSSV activity of PmGILT, a yeast 2-hybrid (Y2H) assay was performed to identify WSSV proteins targeted by PmGILT. The assay revealed 4 potential PmGILT-interacting WSSV proteins: WSSV002, WSSV164, WSSV189, and WSSV471. Three of these 4 WSSV proteins (WSSV002, WSSV164 and WSSV189) were successfully produced and confirmed to interact with PmGILT in in vitro pull-down assays. WSSV189 and WSSV471 were previously identified as structural proteins, whereas WSSV164 is an immediate-early protein which has anti-melanization activity, and WSSV002 is an unknown. Because of the thiol reductase activity of PmGILT, WSSV164 and WSSV189, both of which are cysteine-containing WSSV proteins, were chosen for disulfide bond reduction assays. PmGILT reduced intrachain disulfide bonds in both WSSV proteins, suggesting that PmGILT exerts its anti-WSSV activity via its thiol reductase activity to disrupt the WSSV protein complex and restore the melanization activity of PmproPO1 and PmproPO2.


Assuntos
Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Antivirais , Dissulfetos , Técnicas do Sistema de Duplo-Híbrido
19.
An Acad Bras Cienc ; 91(2): e20180547, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038539

RESUMO

Dynamic thiol-disulfide homeostasis is considered to have critical roles in maintenance of physiological functioning. We aimed to reveal whether there is any specific aberration in thiol-disulfide homeostasis in three distinct categories of individuals, including those who 1) exercise regularly (fitness group), 2) have a sedentary lifestyle (sedentary group) and 3) are overweight or obese (overweight/obese group). 72 male individuals were included in the study, 21 of whom were in fitness group, 28 of whom were overweight or obese and 23 of whom had a sedentary lifestyle. Plasma native thiol (-SH) and total thiol [(-SH) + (-S-S-)] levels were quantitatively determined. Total thiol levels in sedentary group were significantly lower than those in overweight/obese (p<0.05) and fitness groups (p<0.001). Also, disulfide values in fitness group were significantly higher than those in sedentary and overweight/obese groups (p<0.005, p<0.05). On the other hand, disulfide level, reduced and oxidized thiol ratios and oxidation/reduction ratio in fitness group differed significantly from the other groups (p<0.05). Thiol-disulfide homeostasis varies depending on lifestyle. The results of our study indicate that higher total thiol and disulfide levels are conspicuously distinctive features of thiol-disulfide homeostasis in individuals exercising regularly.


Assuntos
Dissulfetos/sangue , Exercício/fisiologia , Obesidade/sangue , Sobrepeso/sangue , Comportamento Sedentário , Compostos de Sulfidrila/sangue , Adulto , Análise de Variância , Antioxidantes/fisiologia , Índice de Massa Corporal , Homeostase/fisiologia , Humanos , Masculino , Estresse Oxidativo/fisiologia , Curva ROC , Valores de Referência , Estatísticas não Paramétricas
20.
Phys Chem Chem Phys ; 21(22): 11916-11923, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31125036

RESUMO

Peptide structural transformation and aggregation is associated with a large number of outsider aetiology diseases, and it is intrinsically linked to amyloid peptide aggregation. Diphenylalanine self-assembled structures are used as robust minimalist beta amyloids not only to elucidate protein aggregation but also to generate hydrogels. Herein, we employed a neutral model peptide Ac-Phe-Phe-Cys-NH2 (Ac-FFC-NH2) to elucidate the role of intermolecular disulfide bonds in protein fibrillation. The Ac-FFC-NH2 peptide initially self-assembles into nanospheres that evolve to amyloid type fibrils under mild oxidative conditions. Incubation of the peptide in the presence of the chemical reduction agent TCEP inhibits the formation of the fibrils, detecting only spherical nanostructures with no secondary structure. Importantly, we triggered the transformation of the preformed linear straight amyloid fibrils to non-fibrillar structures by TCEP treatment. Under this condition, the amyloid bundles are transformed into rings, which evolve to a new spherical microstructure. We showed that the chemical reduction of intermolecular S-S in internal amyloid sequences might favour the off-path intermediates of amyloid fibril growth, even when the fibrils are formed. Our findings demonstrated that in internal amyloid sequences, the formation of intermolecular S-S promotes the formation of amyloid type fibrils; meanwhile, its reduction stabilises non-fibrillar structures. Altogether, this work provides fundamental understanding at the molecular and supramolecular level, thus facilitating the rational design of therapeutic tools for protein aggregation diseases.


Assuntos
Amiloide/química , Dissulfetos/química , Oligopeptídeos/química , Oligopeptídeos/síntese química , Oxirredução , Multimerização Proteica
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