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1.
Nat Commun ; 11(1): 1262, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152269

RESUMO

Binding of biomolecules to crystal surfaces is critical for effective biological applications of crystalline nanomaterials. Here, we present the modulation of exposed crystal facets as a feasible approach to enhance specific nanocrystal-biomolecule associations for improving cellular targeting and nanomaterial uptake. We demonstrate that facet-engineering significantly enhances transferrin binding to cadmium chalcogenide nanocrystals and their subsequent delivery into cancer cells, mediated by transferrin receptors, in a complex biological matrix. Competitive adsorption experiments coupled with theoretical calculations reveal that the (100) facet of cadmoselite and (002) facet of greenockite preferentially bind with transferrin via inner-sphere thiol complexation. Molecular dynamics simulation infers that facet-dependent transferrin binding is also induced by the differential affinity of crystal facets to water molecules in the first solvation shell, which affects access to exposed facets. Overall, this research underlines the promise of facet engineering to improve the efficacy of crystalline nanomaterials in biological applications.


Assuntos
Proteínas de Transporte/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Transferrina/química , Adsorção , Fenômenos Biofísicos , Cádmio/química , Células HeLa , Humanos , Simulação de Dinâmica Molecular , Tamanho da Partícula , Receptores da Transferrina , Propriedades de Superfície , Difração de Raios X
2.
Sensors (Basel) ; 19(23)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31805717

RESUMO

The level of human serum albumin (HSA) in biological fluids is a key health indicator and its quantitative determination has great clinical importance. In this study, we developed a selective and sensitive fluorescent HSA probe by fluorescence-based high-throughput screening of a set of fluorescent thieno[3,2-b]pyridine-5(4H)-one derivatives against major plasma proteins: HSA, bovine serum albumin (BSA), globulin, fibrinogen, and transferrin. The fluorophore chosen finally (4) showed noticeable fluorescence enhancement in the presence of HSA (160-fold increase), and it exhibited rapid response, high sensitivity (detection limit 8 nM), and the ability to clearly distinguish HSA from BSA in pH 9 buffer condition. Moreover, the probe could be applicable to detect trace amounts of HSA in an artificial urine sample; further, it might be applied to the determination of the HSA concentration in complex biological samples for pre-clinical diagnosis.


Assuntos
Corantes Fluorescentes/química , Soroalbumina Bovina/química , Albumina Sérica Humana/química , Animais , Bovinos , Fibrinogênio/química , Globulinas/química , Humanos , Transferrina/química
3.
BMC Res Notes ; 12(1): 802, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831048

RESUMO

OBJECTIVE: The association between unbalanced iron indices and the conditions of schizophrenia are not well understood. Liver dysfunction which has been linked to iron metabolism might be a contributing factor. This case-control study evaluated serum iron indices and liver function in treatment-naïve schizophrenia patients and those already on treatment at the Psychiatric Department of the Komfo Anokye Teaching Hospital (KATH), Kumasi-Ghana. RESULTS: The mean age of the respondents was 39.6 ± 0.8 years. Increased levels of serum iron, TS, AST, ALT and AST:ALT ratio and lower levels of UIBC, TIBC, Transferrin, and log Ferritin:AST ratio levels were observed among the treatment-naïve group compared to the control. The treatment-naïve and treatment groups showed significantly higher serum AST:ALT ratio, and lower log10ferrtin:AST ratio than the healthy controls. There was a significant correlation between log10ferritin and AST, and log10ferritin and GGT in both treatments (r = 0.343; p = 0.003, and r = 0.502; p = 0.001 respectively) and treatment-naïve groups (r = 0.348; p = 0.002, and r = 0.614; p < 0.001 respectively). Percentage transferrin saturation correlated significantly with GGT only, in the treatment-naïve group (r = 0.667; p < 0.001), and ALT and GGT in the treatment group (r = 0.252; p = 0.030 and r = 0.646; p = 0.014 respectively).


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Ferritinas/sangue , Sobrecarga de Ferro/sangue , Ferro/sangue , Esquizofrenia/complicações , Adulto , Alanina Transaminase/análise , Aspartato Aminotransferases/análise , Estudos de Casos e Controles , Feminino , Ferritinas/análise , Gana , Humanos , Sobrecarga de Ferro/complicações , Fígado/metabolismo , Testes de Função Hepática , Masculino , Esquizofrenia/sangue , Transferrina/química , Transferrina/metabolismo
4.
Med Sci Monit ; 25: 9737-9751, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31856143

RESUMO

BACKGROUND This study aimed to prepare doxorubicin- and tetrahydrocurcumin-loaded and transferrin-modified PEG-PLGA nanoparticles (Tf-NPs-DOX-THC) for enhanced and synergistic chemoradiotherapy. MATERIAL AND METHODS Tf-NPs-DOX-THC were prepared via the double-emulsion method. The morphologies and particle sizes of the prepared nanoparticles were examined by TEM and DLS, respectively. The in vitro MTT, apoptosis, and clone formation assays were performed to detect the proliferation and radiosensitivity of cells with various treatments. Cellular uptake assay was also conducted. The tissue distribution of Tf-NPs was investigated by ex vivo DOX fluorescence imaging. The in vivo tumor growth inhibition efficiency of various treatments was evaluated in orthotopic C6 mouse models and C6 subcutaneously grafted mouse models. RESULTS Tf-NPs-DOX-THC exhibited high drug-loading efficiency (6.56±0.32%) and desirable particle size (under 250 nm). MTT, apoptosis, and clone formation assays revealed the enhanced anti-cancer activity and favorable radiosensitizing effect of Tf-NPs-DOX-THC. Strong fluorescence was observed in the brains of mice treated with Tf-NPs-DOX. The in vitro release of drug from nanoparticles was in a pH-sensitive manner. Tf-NPs-DOX-THC in combination with radiation also achieved favorable anti-tumor efficacy in vivo. CONCLUSIONS All results suggest that a combination of Tf-NPs-DOX-THC and radiation is a promising strategy for synergistic and sensitizing chemoradiotherapy of glioma.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Glioma/tratamento farmacológico , Poliésteres/química , Polietilenoglicóis/química , Animais , Linhagem Celular Tumoral , Quimiorradioterapia/métodos , Curcumina/análogos & derivados , Curcumina/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/farmacologia , Emulsões , Glioma/patologia , Humanos , Lactatos/química , Camundongos , Camundongos Nus , Nanopartículas/administração & dosagem , Tamanho da Partícula , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Ratos , Distribuição Tecidual , Transferrina/química , Transferrina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Clin Biochem ; 74: 31-35, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31672652

RESUMO

BACKGROUND: In the chronic inflammation process in the course of rheumatoid arthritis (RA), many alterations in the expression of plasma proteins, as well as their posttranslational modifications (including glycosylation) can occur. Taking into account the disturbances in protein glycosylation and the emerging new treatment regimens, the aim of this study was to assess the serum profile of transferrin isoforms in RA patients treated with biological drugs. METHODS: The study included 20 patients (16 females and 4 males; mean age: 53.4 years; range: 24-67) with rheumatoid arthritis treated with rituximab. Serum samples were taken 3 times: before and 3 and 6 months during treatment. The isoforms of transferrin were separated by capillary electrophoresis (MINICAP electrophoretic system, Sebia, France) into five major fractions: asialo-, disialo-, trisialo-, tetrasialo- and pentasialotransferrin. The results were calculated as relative concentrations of each fraction. RESULTS: The median trisialotransferrin relative concentrations after 3 and 6 months treatment (4.40% and 4.10%, respectively) were significantly higher (p = 0.013, p = 0.009, respectively) than before treatment (3.50%). The levels of serum pentasialotransferrin were also increased 3 and 6 months following treatment (16.5% and 17.7%, p = 0.005 and p = 0.006, respectively) as compared to those before therapy (14.5%), while tetrasialotransferrin concentrations were lower (80.3% and 78.4%, p = 0.009 and p = 0.008, respectively) than before treatment (81.5%). Trisialotransferrin relative concentration correlated with Hb (p = 0.019), whereas pentasialotransferrin with PLT (p = 0.036) after treatment. CONCLUSIONS: This study indicates that treatment with rituximab of RA patients alters the serum profile of transferrin isoforms. Tri-, tetra- and pentasialotransferrin relative concentrations measurements can be a useful tool to monitor therapy.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/terapia , Produtos Biológicos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Rituximab/uso terapêutico , Transferrina/análise , Adulto , Idoso , Biomarcadores/sangue , Monitoramento de Medicamentos/métodos , Eletroforese Capilar , Feminino , Seguimentos , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/sangue , Índice de Gravidade de Doença , Transferrina/química , Resultado do Tratamento , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 116(46): 22938-22945, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659038

RESUMO

Developing a mechanistic understanding of protein dynamics and conformational changes at polymer interfaces is critical for a range of processes including industrial protein separations. Salting out is one example of a procedure that is ubiquitous in protein separations yet is optimized empirically because there is no mechanistic description of the underlying interactions that would allow predictive modeling. Here, we investigate peak narrowing in a model transferrin-nylon system under salting out conditions using a combination of single-molecule tracking and ensemble separations. Distinct surface transport modes and protein conformational changes at the negatively charged nylon interface are quantified as a function of salt concentration. Single-molecule kinetics relate macroscale improvements in chromatographic peak broadening with microscale distributions of surface interaction mechanisms such as continuous-time random walks and simple adsorption-desorption. Monte Carlo simulations underpinned by the stochastic theory of chromatography are performed using kinetic data extracted from single-molecule observations. Simulations agree with experiment, revealing a decrease in peak broadening as the salt concentration increases. The results suggest that chemical modifications to membranes that decrease the probability of surface random walks could reduce peak broadening in full-scale protein separations. More broadly, this work represents a proof of concept for combining single-molecule experiments and a mechanistic theory to improve costly and time-consuming empirical methods of optimization.


Assuntos
Cromatografia/instrumentação , Nylons/química , Polímeros/química , Transferrina/química , Cinética , Membranas Artificiais , Método de Monte Carlo , Conformação Proteica , Sais/química , Imagem Individual de Molécula
7.
Molecules ; 24(19)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31574945

RESUMO

Glioma is one of the most aggressive and common malignant brain tumors. Due to the presence of the blood-brain barrier (BBB), the effectiveness of therapeutics is greatly affected. In this work, to develop an efficient anti-glioma drug with targeting and which was able to cross the BBB, cell-penetrating peptides (R8) and transferrin co-modified doxorubicin (DOX)-loaded liposomes (Tf-LPs) were prepared. Tf-LPs possessed a spherical shape and uniform size with 128.64 nm and their ξ-potential was 6.81 mV. Tf-LPs were found to be stable in serum within 48 h. Uptake of Tf-LPs in both U87 and GL261 cells was analyzed by confocal laser scanning microscopy and by flow cytometry. Tf-LPs were efficiently taken up by both U87 and GL261 cells. Moreover, Tf-LPs exhibited sustained-release. The cumulative release of DOX from Tf-LPs reached ~50.0% and showed excellent anti-glioma efficacy. Histology of major organs, including brain, heart, liver, spleen, lungs and kidney, and the bodyweight of mice, all indicated low toxicity of Tf-LPs. In conclusion, Tf-LPs showed great promise as an anti-glioma therapeutic agent.


Assuntos
Antineoplásicos/administração & dosagem , Peptídeos Penetradores de Células/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Transferrina/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos , Camundongos , Polietilenoglicóis/administração & dosagem , Transferrina/química , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Pharm Res ; 36(11): 161, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529284

RESUMO

PURPOSE: Apolipoprotein E2 (ApoE2) gene therapy is a potential disease-modifying therapy for Alzheimer's disease (AD). We investigated the potential of plasmid encoding ApoE2 loaded brain-targeted functionalized-liposomes for treatment of AD. This was achieved via systemic administration of liposomes entrapping therapeutic gene targeting the brain of mice. METHODS: Targeting and transfection efficiency of designed liposomes were determined in bEnd.3, primary glial and primary neuronal cells. The ability of liposomal formulations to translocate across in vitro blood-brain barrier (BBB) and, thereafter, transfect primary neuronal cells was investigated using in vitro triple co-culture BBB model. We quantified ApoE expression in the brain of mice after single intravenous injection of brain-targeted liposomes loaded with plasmid ApoE2. RESULTS: Dual surface modification enhanced the in vitro transfection efficiency of designed liposomes. Successful delivery of therapeutic gene overcoming BBB by Transferrin-Penetratin- modified liposomes was demonstrated both in vitro and in vivo. Significant (p < 0.05) increase in ApoE levels in the brain of mice was observed after intravenous administration of Tf-Pen-liposomes encasing plasmid ApoE2. CONCLUSION: The results indicate that dual-ligand based liposomal gene delivery systems had both enhanced brain targeting and gene delivery efficiencies. Transferrin-Penetratin modified liposomes for delivery of plasmid ApoE2 has great potential for AD treatment.


Assuntos
Apolipoproteína E2/genética , Barreira Hematoencefálica/metabolismo , Terapia Genética , Lipossomos/química , Nanopartículas/química , Doença de Alzheimer/terapia , Animais , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/metabolismo , Feminino , Humanos , Lipossomos/administração & dosagem , Lipossomos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo , Transferrina/química , Transferrina/metabolismo
9.
Eur J Med Chem ; 183: 111713, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31557610

RESUMO

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) has become the world's leading killer disease due to a single infectious agent which survives in the host macrophage for the indefinite period. Hence, it is necessary to enhance the efficacy of the clinically existing antitubercular agents or to discover new anti antitubercular agents. Here, we report the synthesis, characterization and antimycobacterial evaluation of protein-drug conjugates. A carrier protein, Transferrin (Tf) was covalently conjugated to isoniazid (INH) utilizing hydrazone and amide linkers. The purity of the reactions was confirmed by SDS-PAGE while conjugation was confirmed by UV-visible spectrophotometry, MALDI-TOF analysis, and FTIR spectrophotometry. The in vitro antitubercular assay result showed that the inhibitory activity of the parent drug was conserved in both the conjugates. The conjugates were effective against intracellular Mtb H37Rv and were devoid of cytotoxic effect at therapeutic concentration.


Assuntos
Antituberculosos , Isoniazida , Mycobacterium tuberculosis/efeitos dos fármacos , Transferrina , Tuberculose/tratamento farmacológico , Antituberculosos/síntese química , Antituberculosos/farmacologia , Estabilidade de Medicamentos , Humanos , Isoniazida/síntese química , Isoniazida/química , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Transferrina/química , Tuberculose/microbiologia
10.
Blood ; 134(17): 1373-1384, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31434707

RESUMO

Transferrin, the major plasma iron-binding molecule, interacts with cell-surface receptors to deliver iron, modulates hepcidin expression, and regulates erythropoiesis. Transferrin binds and releases iron via either or both of 2 homologous lobes (N and C). To test the hypothesis that the specificity of iron occupancy in the N vs C lobe influences transferrin function, we generated mice with mutations to abrogate iron binding in either lobe (TfN-bl or TfC-bl). Mice homozygous for either mutation had hepatocellular iron loading and decreased liver hepcidin expression (relative to iron concentration), although to different magnitudes. Both mouse models demonstrated some aspects of iron-restricted erythropoiesis, including increased zinc protoporphyrin levels, decreased hemoglobin levels, and microcytosis. Moreover, the TfN-bl/N-bl mice demonstrated the anticipated effect of iron restriction on red cell production (ie, no increase in red blood cell [RBC] count despite elevated erythropoietin levels), along with a poor response to exogenous erythropoietin. In contrast, the TfC-bl/C-bl mice had elevated RBC counts and an exaggerated response to exogenous erythropoietin sufficient to ameliorate the anemia. Observations in heterozygous mice further support a role for relative N vs C lobe iron occupancy in transferrin-mediated regulation of iron homeostasis and erythropoiesis.


Assuntos
Eritropoese , Ferro/metabolismo , Transferrina/metabolismo , Animais , Sítios de Ligação , Contagem de Eritrócitos , Eritropoetina/metabolismo , Feminino , Homeostase , Masculino , Camundongos , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transferrina/química , Transferrina/genética
11.
ACS Appl Mater Interfaces ; 11(37): 33637-33649, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31433156

RESUMO

There is a dire need to develop more effective therapeutics to combat brain cancer such as glioblastoma multiforme (GBM). An ideal treatment is expected to target deliver chemotherapeutics to glioma cells across the blood-brain barrier (BBB). The overexpression of transferrin (Tf) receptor (TfR) on the BBB and the GBM cell surfaces but not on the surrounding cells renders TfR a promising target. While porous silicon nanoparticles (pSiNPs) have been intensely studied as a delivery vehicle due to their high biocompatibility, degradability, and drug-loading capacity, the potential to target deliver drugs with transferrin (Tf)-functionalized pSiNPs remains unaddressed. Here, we developed and systematically evaluated Tf-functionalized pSiNPs (Tf@pSiNPs) as a glioma-targeted drug delivery system. These nanoparticles showed excellent colloidal stability and had a low toxicity profile. As compared with nontargeted pSiNPs, Tf@pSiNPs were selective to BBB-forming cells and GBM cells and were efficiently internalized through clathrin receptor-mediated endocytosis. The anticancer drug doxorubicin (Dox) was effectively loaded (8.8 wt %) and released from Tf@pSiNPs in a pH-responsive manner over 24 h. Furthermore, the results demonstrate that Dox delivered by Tf@pSiNPs induced significantly enhanced cytotoxicity to GBM cells across an in vitro BBB monolayer compared with free Dox. Overall, Tf@pSiNPs offer a potential toolbox for enabling targeted therapy to treat GBM.


Assuntos
Doxorrubicina , Portadores de Fármacos , Glioblastoma/tratamento farmacológico , Nanopartículas , Silício , Transferrina , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico , Porosidade , Silício/química , Silício/farmacocinética , Silício/farmacologia , Transferrina/química , Transferrina/farmacocinética , Transferrina/farmacologia
12.
Curr Pharm Biotechnol ; 20(12): 1028-1036, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364512

RESUMO

BACKGROUND & OBJECTIVE: The present study was aimed at characterizing the conformational alterations induced in human transferrin, the iron regulatory protein by glyoxal. Since protein aggregation is at the core of many disorders, thus interest in this domain has increased significantly during the past years. METHODS: In our present study, the effect of glyoxal was monitored on human transferrin using multispectroscopic and multi-microscopic studies. RESULTS: Intrinsic fluorescence spectroscopy suggested changes in native conformation of human transferrin evident by decreased fluorescence and blue shift in the presence of glyoxal. Further, extrinsic fluorescence was retorted and the results showed the formation of aggregates; apparent by increased Congo red (CR) absorbance, Thioflavin T (ThT) and ANS fluorescence and TEM of human transferrin in the presence of glyoxal. Molecular docking was also employed to see which residues are at core of human transferrin and glyoxal interaction. Reactive oxygen species (ROS) generation assays revealed enhanced ROS levels by human transferrin after treatment with glyoxal. CONCLUSION: Thus, our study proposes that glyoxal induces the formation of aggregates in human transferrin. These aggregates further generate ROS which are key players in the complications associated with diabetes mellitus, giving our study clinical perspective.


Assuntos
Glioxal/química , Glioxal/farmacologia , Agregados Proteicos/efeitos dos fármacos , Transferrina/química , Células Cultivadas , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Microscopia Eletrônica de Transmissão , Simulação de Acoplamento Molecular , Ligação Proteica , Espécies Reativas de Oxigênio , Espectrometria de Fluorescência
13.
Mikrochim Acta ; 186(8): 542, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31317336

RESUMO

Polyacrylonitrile fibers with and without magnetic nanoparticles (Fe3O4 NPs) were prepared by electrospinning. The pure polyacrylonitrile (PAN) fibers and the composited polyacrylonitrile (PAN/Fe3O4) fibers were studied with respect to their capability for enrichment of glycoproteins. Specifically, the glycoproteins ovalbumin (OB) and transferrin (Trf) were studied and compared to the non-glycoproteins bovine serum albumin and lysozyme. Following adsorption and subsequent protein elution with 0.1 wt% of CTAB solution, the glycoproteins were analyzed by SDS polyacrylamide gel electrophoresis. The strong interaction between PAN or PAN/Fe3O4 fibers and glycoproteins is attributed to the synergistic effects of hydrophilic and hydrogen bond interactions. The PAN/Fe3O4 fibers have an attractive additional feature of allowing magnetic separation. The PAN and PAN/Fe3O4 fibers have a high adsorption capacity toward OB and Trf. The treated PAN/Fe3O4 fibers display good selectivity, fast adsorption kinetics, and were applied to extractions of mixed protein samples. The detection limits of OB and Trf are 0.32 and 0.22 µg·mL-1, respectively. The PAN/Fe3O4 fibers offered an alternative solution for adsorption of glycoproteins from biological samples. Graphical abstract The pure polyacrylonitrile (PAN) fibers and the composited polyacrylonitrile (PAN/Fe3O4) fibers were studied with respect to their capability for enrichment of glycoproteins: glycoproteins ovalbumin (OB) and transferrin (Trf). The treated PAN/Fe3O4 fibers showed fast adsorption kinetics, were applied in a physiological state, mixed and real samples.


Assuntos
Resinas Acrílicas/química , Glicoproteínas/química , Nanopartículas de Magnetita/química , Ovalbumina/química , Transferrina/química , Adsorção , Muramidase/química , Soroalbumina Bovina/química
14.
ACS Appl Mater Interfaces ; 11(33): 29490-29497, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31355624

RESUMO

Though abundant researches report that artemisinin could inhibit cancer cell growth via generating toxic reactive oxygen species (ROS), the therapeutic efficiency of artemisinin for cancer treatment is still limited owing to the insufficient intracellular ferrous ion and defensive effect of intracellular glutathione. Herein, we report a cathepsin B-controllable smart nanomedicine based on the structural and pharmacodynamic characteristics of artemisinin, which employed transferrin-peptide-modified mesoporous silica to codeliver artemisinin and buthionine-sulfoximine, a glutathione scavenger, into cancer cells. As a gatekeeper, the transferrin-peptide can not only target the cancer cells but also supply the extra ferrous iron to catalyze artemisinin to produce excessive ROS to kill cancer cells efficiently. Once the designed nanomedicine attack into lysosome of tumor cells, the cargos of nanomedicine can be released in the presence of cathepsin B to immediately activate self-amplification of oxidative stress by simultaneously elevating the levels of ROS and weakening the levels of glutathione. We anticipate that this rational design strategy provides innovative opportunities for artemisinin in the clinical application of cancer.


Assuntos
Artemisininas/química , Nanomedicina/métodos , Neoplasias/metabolismo , Animais , Catepsina B/química , Glutationa/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química , Transferrina/química
15.
Int J Biol Macromol ; 138: 718-724, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351151

RESUMO

Protein aggregation and glycation is gaining increased attention in recent times as protein aggregates and advanced glycation end products (AGEs) play a pivotal role in many disorders. The purpose of our study was to have an insight into AGEs and aggregates formation of human transferrin (hTF) in the presence of methylglyoxal (MG) employing intrinsic, ANS, Thioflavin T fluorescence, circular dichroism (CD) spectroscopy, docking studies and microscopy. In our study, effect of varying concentration of MG was observed on hTF retorting multispectroscopic, in silico and microscopic approach. Intrinsic fluorescence showed an increase in fluorescence of hTF in presence of MG. The obtained AGEs of hTF in the presence of MG were characterized with respect to fluorescence of AGEs specific adducts. Further, aggregates of hTF were characterized employing ThT fluorescence, transmission electron microscopy (TEM) and fluorescence microscopy. Fluorescence microscopy and TEM confirmed the presence of hTF aggregates in the presence of 50 mM MG; aggregates to be globular in nature. Molecular docking was also employed highlighting the important residues playing a pivotal role in this interaction. Thus, our study characterized the AGEs and aggregates of clinically important protein, hTF; level of MG increases in various pathological conditions giving our study clinical perspective.


Assuntos
Produtos Finais de Glicação Avançada/química , Agregados Proteicos , Aldeído Pirúvico/química , Transferrina/química , Fenômenos Biofísicos , Glicosilação , Humanos , Modelos Moleculares , Conformação Molecular , Agregados Proteicos/efeitos dos fármacos , Aldeído Pirúvico/farmacologia , Análise Espectral
16.
ACS Chem Biol ; 14(7): 1507-1514, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31243955

RESUMO

Chemotherapeutics that self-assemble into colloids have limited efficacy above their critical aggregation concentration due to their inability to penetrate intact plasma membranes. Even when colloid uptake is promoted, issues with colloid escape from the endolysosomal pathway persist. By stabilizing acid-responsive lapatinib colloids through coaggregation with fulvestrant, and inclusion of transferrin, we demonstrate colloid internalization by cancer cells, where subsequent lapatinib ionization leads to endosomal leakage and increased cytotoxicity. These results demonstrate a strategy for triggered drug release from stable colloidal aggregates.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Coloides/química , Preparações de Ação Retardada/química , Fulvestranto/administração & dosagem , Antineoplásicos Hormonais/farmacocinética , Antineoplásicos Hormonais/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endossomos/metabolismo , Fulvestranto/farmacocinética , Fulvestranto/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Transferrina/química
17.
Chemistry ; 25(45): 10698-10709, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31149749

RESUMO

Two structurally constrained chelators based on a fused bicyclic scaffold, 4-amino-4-methylperhydro-pyrido[1,2-a][1,4]diazepin-N,N',N'-triacetic acids [(4R*,10aS*)-PIDAZTA (L1) and (4R*,10aR*)-PIDAZTA (L2)], were designed for the preparation of GaIII -based radiopharmaceuticals. The stereochemistry of the ligand scaffold has a deep impact on the properties of the complexes, with unexpected [Ga(L2)OH] species being superior in terms of both thermodynamic stability and inertness. This peculiar behavior was rationalized on the basis of molecular modeling and appears to be related to a better fit in size of GaIII into the cavity of L2. Fast and efficient formation of the GaIII chelates at room temperature was observed at pH values between 7 and 8, which enables 68 Ga radiolabeling under truly physiological conditions (pH 7.4).


Assuntos
Compostos Bicíclicos com Pontes/química , Quelantes/química , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Cristalografia por Raios X , Teoria da Densidade Funcional , Radioisótopos de Gálio/química , Meia-Vida , Humanos , Concentração de Íons de Hidrogênio , Cinética , Conformação Molecular , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismo , Transferrina/química
18.
J Sep Sci ; 42(17): 2788-2795, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31218807

RESUMO

With the explosive growth of the bioscience and biopharmaceuticals, the demand for high efficient analysis and separation of proteins is urgent. High-performance liquid chromatography is an appropriate technology for this purpose, and the stationary phase is the kernel to the separation efficiency. In this study, flow-through poly(styrene-co-divinylbenzene) microspheres characteristic of the binary pores, i.e. flow-through pores and mesopores, were synthesized; this special porous structure would benefit the convective mass transfer while guarantee the high specific surface area. Owing to the hydrophobic nature, poly(styrene-co-divinylbenzene) microspheres were suitable as the reversed-phase stationary phase for separation of proteins. For the high permeability of the poly(styrene-co-divinylbenzene) microspheres packed column, fast separation of the studied six proteins in ∼2 min was achieved. The recoveries of studied proteins were acceptable in the range of 79.0-99.4%. The proposed column had good pH stability of 1-13 and repeatability. Moreover, the column was applied for egg white fast separation, further demonstrating its applicability for complex bio-sample separation. The flow-through poly(styrene-co-divinylbenzene) microspheres were promising for fast separation of large molecules.


Assuntos
Cromatografia de Fase Reversa , Microesferas , Poliestirenos/química , Animais , Bovinos , Citocromos c/química , Citocromos c/isolamento & purificação , Lactoglobulinas/química , Lactoglobulinas/isolamento & purificação , Muramidase/química , Muramidase/isolamento & purificação , Muramidase/metabolismo , Ribonuclease Pancreático/química , Ribonuclease Pancreático/isolamento & purificação , Ribonuclease Pancreático/metabolismo , Soroalbumina Bovina/química , Soroalbumina Bovina/isolamento & purificação , Suínos , Transferrina/química , Transferrina/isolamento & purificação , Tripsina/química , Tripsina/isolamento & purificação , Tripsina/metabolismo
19.
J Pharm Biomed Anal ; 174: 191-197, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31174130

RESUMO

Enrichment and/or purification of intact glycopeptides and derivatized glycans are essential for mass spectrometry-based glycoproteomics and glycomics because of analytical challenges observed in the analysis. Here, a titania-based material was synthesized using a facile sol-gel method for the efficient analysis of glycopeptides and glycans. The glycopeptide enrichment efficacy of the titania-based sol-gel material was evaluated by the enrichment of IgG N-glycopeptides from their proteolytic products. The selectivity and sensitivity (0.5 fmol µL-1) of the titania-based sol-gel material was found to be quite high when compared with commercial TiO2. A pipette-tip application for rapid glycoproteomic and glycomic analysis was developed by packing titania-based material into the pipette tips. The released and derivatized N-glycans of human plasma, IgG and human transferrin were successfully purified by titania glyco-purification tips for the analysis by MALDI-MS. The enrichment performance of the titania glyco-purification tip was tested using human plasma digest as a real-world complex sample and, 112 N-glycopeptides from human plasma glycoproteins were detected by the analysis of enriched samples by nLC-QTOF-MS/MS. Finally, the structural characterization of the material was achieved in detail using various characterization approaches.


Assuntos
Glicopeptídeos/sangue , Polissacarídeos/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Titânio/química , Glicômica , Glicosilação , Humanos , Imunoglobulina G/química , Espectrometria de Massas , Teste de Materiais , Transição de Fase , Transferrina/química
20.
Molecules ; 24(10)2019 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31109034

RESUMO

Carbon dots (CDs) are fluorescent nanomaterials used extensively in bioimaging, biosensing and biomedicine. This is due in large part to their biocompatibility, photostability, lower toxicity, and lower cost, compared to inorganic quantum dots or organic dyes. However, little is known about the utility of CDs as separation adjuvants in capillary electrophoresis (CE) separations. CDs were synthesized in-house according to a 'bottom-up' method from citric acid or other simple carbon precursors. To demonstrate the applicability of CDs as separation adjuvants, mixtures of holo- (metallated) and apo- (demetallated) forms of transferrin (Tf, an iron transport protein) were analyzed. In the absence of CDs, the proteins were not resolved by a simple CE method; however, upon addition of CDs to the separation buffer, multiple forms of Tf were resolved indicating that CDs are valuable tools to facilitate the separation of analytes by CE. CE parameters including sample preparation, buffer identity, ionic strength, pH, capillary inside diameter, and temperature were optimized. The results suggest that dots synthesized from citric acid provide the best resolution of various different forms of Tf and that CDs are versatile and promising tools to improve current electrophoretic separation methods, especially for metalloprotein analysis.


Assuntos
Carbono , Eletroforese Capilar , Pontos Quânticos , Transferrina/química , Transferrina/isolamento & purificação , Tampões (Química) , Carbono/química , Eletrólitos , Eletroforese Capilar/métodos , Fluorometria , Concentração de Íons de Hidrogênio , Metaloproteínas/química , Metaloproteínas/isolamento & purificação , Temperatura
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