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1.
Food Chem ; 334: 127611, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712493

RESUMO

Plant polyphenols applied as natural antioxidant ingredients, are known to bind to cysteine residues on meat proteins. The aim of this study was to examine the effect of light exposure on the formation of cysteine-phenol adduct in meat added 4-methylcatechol (4MC), a model polyphenol, during storage through quantitative LC-MS/MS-based analysis. Cysteine-4-methylcatechol adduct (Cys-4MC) formation in meat added 1500 ppm 4-MC increased significantly (by 50%) when stored under light in oxygen at 4 °C for 7 days as compared to storage in the dark. This was reflected by a significant decrease in thiol concentrations in the same sample. Gel electrophoresis showed loss in myosin heavy chain (MHC), and a resulting increase in cross-linked MHC (CL-MHC) and larger protein polymers in samples added 4MC. Protein blots stained with nitroblue tetrazolium (NBT) showed intensive protein-polyphenol binding in the meat samples added 4MC, but no major differences between storage conditions.


Assuntos
Catecóis/química , Armazenamento de Alimentos/métodos , Proteínas de Carne/química , Carne , Oxigênio/química , Antioxidantes/química , Cromatografia Líquida , Cisteína/química , Eletroforese em Gel de Poliacrilamida , Luz , Carne/análise , Proteínas de Carne/metabolismo , Cadeias Pesadas de Miosina/química , Compostos de Sulfidrila/química , Espectrometria de Massas em Tandem
2.
AAPS PharmSciTech ; 21(6): 212, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737610

RESUMO

This research aimed to synthesize and evaluate mucoadhesive catechol-functionalized alginate (Cat-Alg) nanoparticles (NPs) for bladder cancer. Cat-Alg was synthesized using coupling chemistry, and the structure was verified using NMR and FT-IR. Cat-Alg NPs were generated by ionic gelation between the synthesized Cat-Alg and calcium chloride. Garcinia mangostana L. extract (GM extract) was entrapped into the NPs during particle formation. The physical characteristics, mucoadhesive properties, drug loading and release, cellular uptake, and anticancer activity of the GM extract-loaded NPs were investigated. The Cat-Alg NPs were spherical with sizes in the range of 155-186 nm. The slightly negative surface charge of the NPs provided them with excellent stability. The Cat-Alg NPs could be retained on a porcine bladder mucosa to a greater extent compared with unmodified Alg NPs. High loading efficiency (71.6%) and loading capacity (292 µg/mg) of GM extract in the NPs were achieved, and a constant release of GM extract was obtained for up to 8 h with zero-order kinetics. Moreover, the GM extract-loaded NPs were deposited in bladder tissue and accumulated in MB49 cells at a higher rate compared with GM extract suspension. In addition, the NPs could kill a mouse urothelial carcinoma cell line with low IC50. Therefore, these NPs have the potential to be a mucoadhesive drug delivery system for bladder cancer treatment. However, additional in vivo investigations are needed for clinical application in cancer treatment. Graphical abstract.


Assuntos
Alginatos/química , Antineoplásicos/uso terapêutico , Catecóis/química , Portadores de Fármacos/química , Nanopartículas/química , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Camundongos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos
3.
Int J Nanomedicine ; 15: 3851-3868, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764919

RESUMO

Purpose: The aim of this study was to develop a means of improving the bioavailability and anticancer activity of urushiol by developing an urushiol-loaded novel tumor-targeted micelle delivery system based on amphiphilic block copolymer poly(ethylene glycol)-b-poly-(ß-amino ester) (mPEG-PBAE). Materials and Methods: We synthesized four different mPEG-PBAE copolymers using mPEG-NH2 with different molecular weights or hydrophobicity levels. Of these, we selected the mPEG5000-PBAE-C12 polymer and used it to develop an optimized means of preparing urushiol-loaded micelles. Response surface methodology was used to optimize this formulation process. The micellar properties, including particle size, pH sensitivity, drug release dynamics, and critical micelle concentrations, were characterized. We further used the MCF-7 human breast cancer cell line to explore the cytotoxicity of these micelles in vitro and assessed their pharmacokinetics, tissue distribution, and antitumor activity in vivo. Results: The resulting micelles had a mean particle size of 160.1 nm, a DL value of 23.45%, and an EE value of 80.68%. These micelles were found to release their contents in a pH-sensitive manner in vitro, with drug release being significantly accelerated at pH 5.0 (98.74% in 72 h) without any associated burst release. We found that urushiol-loaded micelles were significantly better at inducing MCF-7 cell cytotoxicity compared with free urushiol, with an IC50 of 1.21 mg/L. When these micelles were administered to tumor model animals in vivo, pharmacokinetic analysis revealed that the total AUC and MRT of these micelles were 2.28- and 2.53-fold higher than that of free urushiol, respectively. Tissue distribution analyses further revealed these micelles to mediate significantly enhanced tumor urushiol accumulation. Conclusion: The pH-responsive urushiol-loaded micelles described in this study may be ideally suited for clinical use for the treatment of breast cancer.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Catecóis/química , Catecóis/farmacologia , Micelas , Polietilenoglicóis/química , Polímeros/química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Catecóis/farmacocinética , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Tamanho da Partícula , Distribuição Tecidual
4.
Ecotoxicol Environ Saf ; 202: 110898, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32652344

RESUMO

Recent research has shown that the complexation of metals-organics plays an important role in atmospheric particulate matter, whose health effects should be taken into account. This work investigates the interactions between catechols (CAs), i.e., 4-nitrocatechol (4NC) and 4-methylcatechol (4MC), and transition metals (i.e., Fe) in the aqueous phase dark reaction. The formation of Fe/CAs complexes and secondary organics products are analyzed by UV-Vis spectroscopy, stopped-flow spectroscopy, high-resolution mass spectrometry and Raman spectroscopy, while the insoluble particulate matter formed from the CAs/Fe mixtures are characterized by the FTIR, X-ray photoelectron spectroscopy (XPS) and thermogravimetric-quadrupole-mass spectrometry (TG-Q-MS). On the basis of the density functional theory (DFT) calculation and experimental results, the possible formation pathways for the complexes of Fe(III) with 4NC (a proxy for organics) are proposed. The Fe/CAs complexes and organics products perhaps have significant sources of light absorption which play an important role in influencing the intensity of atmospheric radiation and particulate phase photochemistry. Besides, the cytotoxicity is tested as a function of concentrations for CAs/Fe mixtures in BEAS-2B cells. Our results show that CAs/Fe mixtures have strong association with cytotoxicity, indicating the mixtures have potential influence to human health.


Assuntos
Catecóis/química , Compostos Férricos/química , Testes de Toxicidade , Atmosfera/química , Catecóis/toxicidade , Células Epiteliais , Compostos Férricos/toxicidade , Humanos , Espectrometria de Massas , Metais , Material Particulado , Análise Espectral , Água/química
5.
Sci Total Environ ; 736: 139611, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: covidwho-419198

RESUMO

The onset of coronavirus pandemic has sparked a shortage of facemasks in almost all nations. Without this personal protective equipment, healthcare providers, essential workers, and the general public are exposed to the risk of infection. In light of the aforementioned, it is critical to balance the supply and demand for masks. COVID-19 will also ensure that masks are always considered as an essential commodity in future pandemic preparedness. Moreover, billions of facemasks are produced from petrochemicals derived raw materials, which are non-degradable upon disposal after their single use, thus causing environmental pollution and damage. The sustainable way forward is to utilise raw materials that are side-stream products of local industries to develop facemasks having equal or better efficiency than the conventional ones. In this regard, wheat gluten biopolymer, which is a by-product or co-product of cereal industries, can be electrospun into nanofibre membranes and subsequently carbonised at over 700 °C to form a network structure, which can simultaneously act as the filter media and reinforcement for gluten-based masks. In parallel, the same gluten material can be processed into cohesive thin films using plasticiser and hot press. Additionally, lanosol, a naturally-occurring substance, imparts fire (V-0 rating in vertical burn test), and microbe resistance in gluten plastics. Thus, thin films of flexible gluten with very low amounts of lanosol (<10 wt%) can be bonded together with the carbonised mat and shaped by thermoforming to create the facemasks. The carbon mat acting as the filter can be attached to the masks through adapters that can also be made from injection moulded gluten. The creation of these masks could simultaneously be effective in reducing the transmittance of infectious diseases and pave the way for environmentally benign sustainable products.


Assuntos
Controle de Doenças Transmissíveis/instrumentação , Infecções por Coronavirus/prevenção & controle , Máscaras , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus , Tecnologia Biomédica , Catecóis/química , Filtração/instrumentação , Glutens/química , Humanos
6.
Sci Total Environ ; 736: 139611, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32473458

RESUMO

The onset of coronavirus pandemic has sparked a shortage of facemasks in almost all nations. Without this personal protective equipment, healthcare providers, essential workers, and the general public are exposed to the risk of infection. In light of the aforementioned, it is critical to balance the supply and demand for masks. COVID-19 will also ensure that masks are always considered as an essential commodity in future pandemic preparedness. Moreover, billions of facemasks are produced from petrochemicals derived raw materials, which are non-degradable upon disposal after their single use, thus causing environmental pollution and damage. The sustainable way forward is to utilise raw materials that are side-stream products of local industries to develop facemasks having equal or better efficiency than the conventional ones. In this regard, wheat gluten biopolymer, which is a by-product or co-product of cereal industries, can be electrospun into nanofibre membranes and subsequently carbonised at over 700 °C to form a network structure, which can simultaneously act as the filter media and reinforcement for gluten-based masks. In parallel, the same gluten material can be processed into cohesive thin films using plasticiser and hot press. Additionally, lanosol, a naturally-occurring substance, imparts fire (V-0 rating in vertical burn test), and microbe resistance in gluten plastics. Thus, thin films of flexible gluten with very low amounts of lanosol (<10 wt%) can be bonded together with the carbonised mat and shaped by thermoforming to create the facemasks. The carbon mat acting as the filter can be attached to the masks through adapters that can also be made from injection moulded gluten. The creation of these masks could simultaneously be effective in reducing the transmittance of infectious diseases and pave the way for environmentally benign sustainable products.


Assuntos
Controle de Doenças Transmissíveis/instrumentação , Infecções por Coronavirus/prevenção & controle , Máscaras , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus , Tecnologia Biomédica , Catecóis/química , Filtração/instrumentação , Glutens/química , Humanos
7.
Ecotoxicol Environ Saf ; 196: 110561, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276163

RESUMO

A ternary catalysis system was investigated to evaluate the comparative degradation of toxic fungicide metabolite 3,5-dichloroaniline (3,5-DCA) by laccase and MnO2 with mediators. In this study, copper based fungal enzyme laccase (Trametes versicolor origin) and metal catalyst MnO2 with various combinations of phenolic mediators (catechol, syringaldehyde, syringic acid, caffeic acid and gallic acid) were monitored to optimize and screen the better one for 3,5-DCA degradation assay. Catechol showed better potentiality in reduction of 3,5-DCA among the studied mediators. Catechol (2mM) showed the highest reduction rate (99-100%) followed by syringaldehyde (40.51%) with 2U/mL of laccase at 25 °C within 24 h reaction time. Similarly, complete degradation of 3,5-DCA was obtained by catechol (2mM) with 2 mg/mL of MnO2 in MnO2-mediator assay. The notable finding of current study indicated the triggering of catechol for better 3,5-DCA degradation at higher pH condition but inertness in laccase-mediator assay due to laccase destabilization. The reaction pathways of optimized mediator-based catalysis for laccase and MnO2 were proposed. Finally, the optimized laccase-catechol based degradation was considered as a pioneer green catalysis approach to reduce the toxic metabolite 3,5-DCA concentrations in aqueous medium as compared to MnO2-catechol catalysis.


Assuntos
Compostos de Anilina/análise , Fungicidas Industriais/análise , Lacase/metabolismo , Compostos de Manganês/química , Óxidos/química , Trametes/enzimologia , Compostos de Anilina/metabolismo , Benzaldeídos/química , Catálise , Catecóis/química , Fungicidas Industriais/metabolismo , Fenóis/química
8.
Soft Matter ; 16(13): 3257-3266, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32163076

RESUMO

Clickable magnetic nanoparticles have attracted great attention as potential nanoplatforms for biomedical applications because of the high functionalization efficiency of their surfaces with biomolecules, which facilitates their bio-compatibilization. However, the design and synthesis of clickable NPs is still challenging because of the complexity of the chemistry on the magnetic NP surface, thus robust methods that improve the ligand synthesis and the transfer of magnetic NPs in physiological media being in high-demand. In this work, we developed a versatile and enhanced synthetic route to fabricate potentially clickable IONPs of interest in nanomedicine. Catechol anchor ligands with different stereo-electronic features were synthetized from a hetero bi-functional PEG spacer backbone. The resulting catechol ligands transferred in good yields and high stability to magnetic NPs by an improved energetic ligand exchange method that combines sonication and high temperature. The azido functionalized IONPs exhibited excellent characteristics as T2 MRI contrast agents with low cytotoxicity, making these clickable magnetic NPs promising precursors for nanomedicines.


Assuntos
Catecóis/química , Química Click , Compostos Férricos/química , Nanopartículas Metálicas/química , Catecóis/síntese química , Ligantes
9.
Proc Natl Acad Sci U S A ; 117(14): 7613-7621, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32209666

RESUMO

Inspired largely by the role of the posttranslationally modified amino acid dopa (DOPA) in mussel adhesion, catechol functional groups have become commonplace in medical adhesives, tissue scaffolds, and advanced smart polymers. Yet, the complex redox chemistry of catechol groups complicates cross-link regulation, hampering fabrication and the long-term stability/performance of mussel-inspired polymers. Here, we investigated the various fates of DOPA residues in proteins comprising mussel byssus fibers before, during, and after protein secretion. Utilizing a combination of histological staining and confocal Raman spectroscopy on native tissues, as well as peptide-based cross-linking studies, we have identified at least two distinct DOPA-based cross-linking pathways during byssus fabrication, achieved by oxidative covalent cross-linking or formation of metal coordination interactions under reducing conditions, respectively. We suggest that these end states are spatiotemporally regulated by the microenvironments in which the proteins are stored prior to secretion, which are retained after formation-in particular, due to the presence of reducing moieties. These findings provide physicochemical pathways toward greater control over properties of synthetic catechol-based polymers and adhesives.


Assuntos
Bivalves/metabolismo , Catecóis/metabolismo , Di-Hidroxifenilalanina/metabolismo , Sequência de Aminoácidos , Animais , Catecóis/química , Oxirredução , Peptídeos/química , Peptídeos/metabolismo
10.
Food Chem ; 317: 126454, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113140

RESUMO

The reaction efficiency of o-benzoquinones with amines (L-lysine, Nα-acetyl-L-lysine, glycine, L-methionine and L-arginine), thiols (L-cysteine and Nα-acetyl-L-cysteine) and protein (bovine serum albumin) were determined at pH 5.0, 7.0 and 8.0 and scan rate of 10, 50 and 100 mV/s by cyclic voltammetry. Nucleophiles containing multiple nucleophilic groups and nucleophilic group possessing low pKa value would enhance the reactivity of nucleophiles towards o-benzoquinones. The reactivity of different o-benzoquinones with L-lysine/L-cysteine followed the order: protocatechuic acid quinone ≈ catechol quinone > 4-methylbenzoquinone ≈ caffeic acid quinone > rosmarinic acid quinone > chlorogenic acid quinone. The reactivity of quinones would be decreased by the steric hindrance of substituents on quinone ring, and it would also be weakened by enhancing electron cloud density of quinone ring. Adducts generated by the interaction of 4-methylbenzoquinone with amines and thiols were tentatively identified as amine-quinone adduct and thiol-phenol adduct respectively by UPLC-QTOF-MS/MS and cyclic voltammetry.


Assuntos
Aminoácidos/química , Benzoquinonas/química , Técnicas Eletroquímicas/métodos , Aminas/química , Catecóis/química , Cromatografia Líquida , Cisteína/química , Hidroxibenzoatos/química , Fenóis , Quinonas/química , Compostos de Sulfidrila/química , Espectrometria de Massas em Tandem
11.
ChemSusChem ; 13(7): 1856-1863, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32026541

RESUMO

Although several recent publications describe cathodes for electrochemical energy storage materials made from regrown biomass in aqueous electrolytes, their transfer to lithium-organic batteries is challenging. To gain a deeper understanding, we investigate the influences on charge storage in model systems based on biomass-derived, redox-active compounds and comparable structures. Hybrid materials from these model polymers and porous carbon are compared to determine precisely the causes of exceptional capacity in lithium-organic systems. Besides redox activity, particularly, wettability influences capacity of the composites greatly. Furthermore, in addition to biomass-derived molecules with catechol functionalities, which are described commonly as redox-active species in lithium-bio-organic systems, we further describe guaiacol groups as a promising alternative for the first time and compare the performance of the respective compounds.


Assuntos
Aldeídos/química , Catecóis/química , Fontes de Energia Elétrica , Guaiacol/química , Polímeros/química , Eletroquímica , Lítio/química , Oxirredução , Porosidade , Molhabilidade
12.
Mikrochim Acta ; 187(3): 189, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103346

RESUMO

An electrochemical sensor is described for the determination of catechol (CT) based on the nanocomposite of lanthanum cobaltite supported on graphene nanosheets (LaCo/GNS). The nanocomposite was systematically examined by various analytical and spectroscopic methods. The LaCo/GNS-modified electrode exhibites good electrochemical activity towards CT determination compared to other modified and unmodified electrodes. The electrochemical signal was acquired at a redox potential of 0.21 (Epa) and 0.17 (Epc) Volt (vs. Ag/AgCl). The proposed electrode exhibits low detection limit (1.0 nM), wide working range (0.009-132 µM), and good sensitivity (5.68 µA µM-1 cm-2). The electrochemical nanoprobe has good selectivity over potentially interfering compounds. The electrochemical sensor was applied to the analysis of environmental samples with acceptable recovery. Graphical abstractSchematic representation of electrochemical determination of catechol in the environmental sample analysis using lanthanum cobaltite supported on graphene nanosheets.


Assuntos
Catecóis/química , Técnicas Eletroquímicas/métodos , Grafite/química , Lantânio/química , Minerais/química , Nanocompostos/química
13.
Sci Rep ; 10(1): 2584, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054966

RESUMO

Coffee is a complex mixture of many bioactive compounds possessing anti-inflammatory properties. However, the mechanisms by which coffee exerts anti-inflammatory effects remains unclear and the active ingredients have not yet been identified. In this study, we found that coffee extract at more than 2.5%(v/v) significantly inhibited LPS-induced inflammatory responses in RAW264.7 cells and that anti-inflammatory activity of coffee required the roasting process. Interestingly, we identified pyrocatechol, a degradation product derived from chlorogenic acid during roasting, as the active ingredient exhibiting anti-inflammatory activity in coffee. HPLC analysis showed that 124 µM pyrocatechol was included in 100% (v/v) roasted coffee. A treatment with 5%(v/v) coffee extract and more than 2.5 µM pyrocatechol inhibited the LPS-induced activation of NF-κB and also significantly activated Nrf2, which acts as a negative regulator in LPS-induced inflammation. Furthermore, intake of 60% (v/v) coffee extract and 74.4 µM pyrocatechol, which is the concentration equal to contained in 60% (v/v) coffee, markedly inhibited the LPS-induced inflammatory responses in mice. Collectively, these results demonstrated that pyrocatechol, which was formed by the roasting of coffee green beans, is one of the ingredients contributing to the anti-inflammatory activity of coffee.


Assuntos
Anti-Inflamatórios/farmacologia , Catecóis/farmacologia , Café/química , Lipopolissacarídeos/imunologia , Fator 2 Relacionado a NF-E2/imunologia , NF-kappa B/antagonistas & inibidores , Animais , Anti-Inflamatórios/química , Catecóis/química , Inflamação/tratamento farmacológico , Inflamação/imunologia , Camundongos , NF-kappa B/imunologia , Células RAW 264.7
14.
Molecules ; 25(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075064

RESUMO

Freestanding films based on catechol functionalized chitosan (CHI), hyaluronic acid (HA), and bioglass nanoparticles (BGNPs) were developed by spin-coating layer-by-layer assembly (SA-LbL). The catechol groups of 3,4-dihydroxy-l-phenylalanine (DOPA) present in the marine mussels adhesive proteins (MAPs) are the main factors responsible for their characteristic strong wet adhesion. Then, the produced films were cross-linked with genipin to improve their stability in wet state. Overall, the incorporation of BGNPs resulted in thicker and bioactive films, hydrophilic and rougher surfaces, reduced swelling, higher weight loss, and lower stiffness. The incorporation of catechol groups onto the films showed a significant increase in the films' adhesion and stiffness, lower swelling, and weight loss. Interestingly, a synergetic effect on the stiffness increase was observed upon the combined incorporation of BGNPs with catechol-modified polymers, given that such films were the stiffest. Regarding the biological assays, the films exhibited no negative effects on cellular viability, adhesion, and proliferation, and the BGNPs seemed to promote higher cellular metabolic activity. These bioactive LbL freestanding films combine enhanced adhesion with improved mechanical properties and could find applications in the biomedical field, such as guided hard tissue regeneration membranes.


Assuntos
Materiais Biomiméticos/química , Materiais Revestidos Biocompatíveis/química , Nanopartículas/química , Polissacarídeos/farmacologia , Adesivos/química , Adesivos/farmacologia , Catecóis/química , Adesão Celular/efeitos dos fármacos , Cerâmica/química , Quitosana/química , Materiais Revestidos Biocompatíveis/farmacologia , Ácido Hialurônico/química , Teste de Materiais , Membranas Artificiais , Polímeros/química , Polissacarídeos/química , Proteínas/química
15.
ACS Appl Mater Interfaces ; 12(4): 4285-4294, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31903749

RESUMO

Recently, there has been growing interest in replacing severely damaged salivary glands with artificial salivary gland functional units created in vitro by tissue engineering approaches. Although various materials such as poly(lactic-co-glycolic acid), polylactic acid, poly(glycolic acid), and polyethylene glycol hydrogels have been used as scaffolds for salivary gland tissue engineering, none of them is effective enough to closely recapitulate the branched structural complexity and heterogeneous cell population of native salivary glands. Instead of discovering new biomaterial candidates, we synthesized hyaluronic acid-catechol (HACA) conjugates to establish a versatile hyaluronic acid coating platform named "NiCHE (nature-inspired catechol-conjugated hyaluronic acid environment)" for boosting the salivary gland tissue engineering efficacy of the previously reported biomaterials. By mimicking hyaluronic acid-rich niche in the mesenchyme of embryonic submandibular glands (eSMGs) with NiCHE coating on substrates including polycarbonate membrane, stiff agarose hydrogel, and polycaprolactone scaffold, we observed significantly enhanced cell adhesion, vascular endothelial and progenitor cell proliferation, and branching of in vitro-cultured eSMGs. High mechanical stiffness of the substrate is known to inhibit eSMG growth, but the NiCHE coating significantly reduced such stiffness-induced negative effects, leading to successful differentiation of progenitor cells to functional acinar and myoepithelial cells. These enhancement effects of the NiCHE coating were due to the increased proliferation of vascular endothelial cells via interaction between CD44 and surface-immobilized HAs. As such, our NiCHE coating platform renders any kind of material highly effective for salivary gland tissue culture by mimicking in vivo embryonic mesenchymal HA. Based on our results, we expect the NiCHE coating to expand the range of biomaterial candidates for salivary glands and other branching epithelial organs.


Assuntos
Catecóis/química , Proliferação de Células , Células Progenitoras Endoteliais , Ácido Hialurônico/química , Hidrogéis/química , Glândulas Salivares , Engenharia Tecidual , Animais , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos ICR , Glândulas Salivares/citologia , Glândulas Salivares/metabolismo
16.
Int J Mol Sci ; 21(3)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973096

RESUMO

[6]-Gingerol from ginger has received considerable attention as a potential cancer therapeutic agent because of its chemopreventive and chemotherapeutic effects, as well as its safety. In the current study, we examined [6]-gingerol as a natural scavenger of nine ultimate chemical carcinogens to which we are frequently exposed: glycidamide, styrene oxide, aflatoxin B1 exo-8,9-epoxide, ß-propiolactone, ethylene oxide, propylene oxide, 2-cyanoethylene oxide, chloroethylene oxide, and vinyl carbamate epoxide. To evaluate [6]-gingerol efficacy, we expanded our research with the examination of glutathione-the strongest natural scavenger in human cells. The corresponding activation free energies were calculated using Hartree-Fock method with three flexible basis sets and two implicit solvation models. According to our results, [6]-gingerol proves to be an extremely effective scavenger of chemical carcinogens of the epoxy type. On the other hand, with the exception of aflatoxin B1 exo-8,9-epoxide, glutathione represents a relatively poor scavenger, whose efficacy could be augmented by [6]-gingerol. Moreover, our quantum mechanical study of the alkylation reactions of chemical carcinogens with [6]-gingerol and glutathione provide valuable insights in the reaction mechanisms and the geometries of the corresponding transition states. Therefore, we strongly believe that our research forms a solid basis for further computational, experimental and clinical studies of anticarcinogenic properties of [6]-gingerol as well as for the development of novel chemoprophylactic dietary supplements. Finally, the obtained results also point to the applicability of quantum chemical methods to studies of alkylation reactions related to chemical carcinogenesis.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Carcinógenos/química , Carcinógenos/farmacologia , Catecóis/química , Catecóis/farmacologia , Álcoois Graxos/química , Álcoois Graxos/farmacologia , Aflatoxina B1 , Alquilação , Linhagem Celular , Quimioprevenção , Compostos de Epóxi/farmacologia , Óxido de Etileno/análogos & derivados , Gengibre/química , Humanos , Propiolactona , Uretana/análogos & derivados
17.
Mol Med Rep ; 21(3): 1107-1114, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31894337

RESUMO

Protocatechualdehyde (PCA) is considered to be the main phenolic component of Phellinus gilvus responsible for its anticancer properties. Previous studies have demonstrated that PCA can have an anticancer effect on multiple cancer types, but little is known about the effect of PCA on melanoma cells. The present study investigated the inhibitory abilities and potential anticancer mechanisms of PCA on B16­F10 cells using MTT assay. Cell apoptosis and cell cycle were assessed by flow cytometry using Annexin V­FITC and propidium iodide staining. Whole­transcriptome analysis was used to investigate the effects of PCA on gene expression. PCA significantly decreased cell viability, induced cell cycle arrest at G0/G1 phase and promoted apoptosis of B16­F10 cells, suggesting that PCA could have anticancer effects against melanoma cells. Whole­transcriptome analysis indicated that PCA treatment upregulated genes involved in histone modification and decreased the transcription of genes involved in DNA repair and replication. Kyoto Encyclopedia of Genes and Genomes analysis showed that PCA treatment enhanced the complement and coagulation cascades, and the p53 signaling pathway. The present results indicated that PCA could act as an antitumor agent in melanoma cells, which may provide experimental support for the development of novel therapies to treat melanoma.


Assuntos
Apoptose/efeitos dos fármacos , Basidiomycota/química , Benzaldeídos/farmacologia , Catecóis/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Animais , Benzaldeídos/química , Catecóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Humanos , Melanoma Experimental , Camundongos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Biochem Pharmacol ; 173: 113790, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911090

RESUMO

Atopic diseases (atopic dermatitis, asthma and allergic rhinitis) affects a huge number of people around the world and their incidence rate is on rise. Atopic dermatitis (AD) is more prevalent in paediatric population which sensitizes an individual to develop allergic rhinitis and asthma later in life. The complex pathogenesis of these allergic diseases though involves numerous cellular signalling pathways but redox imbalance has been reported to be critical for induction/perpetuation of inflammatory process under such conditions. The realm of complementary and alternative medicine has gained greater attention because of the reported anti-oxidant/anti-inflammatory properties. Several case studies of treating atopic diseases with homeopathic remedies have provided positive results. Likewise, pre-clinical studies suggest that various natural compounds suppress allergic response via exhibiting their anti-oxidant potential. Despite the reported beneficial effects of phytochemicals in experimental model system, the clinical success has not been documented so far. It appears that poor absorption and bioavailability of natural compounds may be one of the reasons for realizing their full potential. The current paper throws light on impact of phytochemicals in the redox linked cellular and signalling pathways that may be critical in manifestation of atopic diseases. Further, an effort has been made to identify the gaps in the area so that future strategies could be evolved to exploit the medicinal value of various phytochemicals for an improved efficiency.


Assuntos
Asma/prevenção & controle , Dermatite Atópica/prevenção & controle , Hipersensibilidade/prevenção & controle , Compostos Fitoquímicos/uso terapêutico , Asma/imunologia , Asma/patologia , Catecóis/química , Catecóis/uso terapêutico , Curcumina/química , Curcumina/uso terapêutico , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Álcoois Graxos/química , Álcoois Graxos/uso terapêutico , Flavonoides/química , Flavonoides/uso terapêutico , Ginsenosídeos/química , Ginsenosídeos/uso terapêutico , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/patologia , Estrutura Molecular , Compostos Fitoquímicos/química , Resveratrol/química , Resveratrol/uso terapêutico
19.
Chemosphere ; 246: 125796, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918103

RESUMO

The theory of "proton-assisted process" can well explain the catalytic mechanism of homoprotocatechuate 2,3-dioxygenase (2,3-HPCD) with a monoanionic substrate (homoprotocatechuate, HPCA). Here a "non-proton-assisted process" is presented to interpret catalytic mechanism of 2,3-HPCD with a dianionic substrate (4-nitrocatechol, 4NC). The ONIOM calculation is performed to investigate the reaction pathway of a wild-type 2,3-HPCD with 4NC (H200H-4NC system). The catalytic reaction is comprised of four steps: (1) A dioxygen attacks the aromatic ring to produce an alkylperoxo species. (2) O-O bond cleavage and the formation of an epoxide species occur. (3) A seven-membered O-heterocyclic compound is generated by the extinction of the epoxy structure. (4) The seven-membered ring undergoes ring opening to form the final product (C2-C3 cleavage product). The effective free energy barrier of the catalytic reaction of the H200H-4NC system is 26.2 kcal mol-1, which is much higher than that of the H200H-HPCA system. Furthermore, two calculated electronic configurations (Fe(III)-O2•- and Fe(III)-SQ•) have a high similarity to previously detected ones, which demonstrates that the Asn200 variant (H200N-4NC variant system) employs a C4 (para-carbon) pathway to produce a C4-C5 cleavage product. Our findings provide an in-depth understanding of the catalytic mechanisms of dianionic catechol and its derivatives.


Assuntos
Biodegradação Ambiental , Catecóis/metabolismo , Dioxigenases/metabolismo , Catálise , Catecóis/química , Compostos Férricos , Oxigênio/química , Prótons
20.
Chem Soc Rev ; 49(2): 433-464, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31939475

RESUMO

Hydrogels are a unique class of polymeric materials that possess an interconnected porous network across various length scales from nano- to macroscopic dimensions and exhibit remarkable structure-derived properties, including high surface area, an accommodating matrix, inherent flexibility, controllable mechanical strength, and excellent biocompatibility. Strong and robust adhesion between hydrogels and substrates is highly desirable for their integration into and subsequent performance in biomedical devices and systems. However, the adhesive behavior of hydrogels is severely weakened by the large amount of water that interacts with the adhesive groups reducing the interfacial interactions. The challenges of developing tough hydrogel-solid interfaces and robust bonding in wet conditions are analogous to the adhesion problems solved by marine organisms. Inspired by mussel adhesion, a variety of catechol-functionalized adhesive hydrogels have been developed, opening a door for the design of multi-functional platforms. This review is structured to give a comprehensive overview of adhesive hydrogels starting with the fundamental challenges of underwater adhesion, followed by synthetic approaches and fabrication techniques, as well as characterization methods, and finally their practical applications in tissue repair and regeneration, antifouling and antimicrobial applications, drug delivery, and cell encapsulation and delivery. Insights on these topics will provide rational guidelines for using nature's blueprints to develop hydrogel materials with advanced functionalities and uncompromised adhesive properties.


Assuntos
Biomimética , Catecóis/química , Hidrogéis/química , Adesivos/química , Propriedades de Superfície
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