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1.
Biofabrication ; 16(3)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38604157

RESUMEN

Scaffolds play a pivotal role in tissue engineering and serve as vital biological substitutes, providing structural support for cell adhesion and subsequent tissue development. An ideal scaffold must possess mechanical properties suitable for tissue function and exhibit biodegradability. Although synthetic polymer scaffolds offer high rigidity and elasticity owing to their reactive side groups, which facilitate tailored mechanical and rheological properties, they may lack biological cues and cause persistent side effects during degradation. To address these challenges, natural polymers have garnered attention owing to their inherent bioactivity and biocompatibility. However, natural polymers such as silk fibroin (SF) and tyramine-modified alginate (AT) have limitations, including uncontrolled mechanical properties and weak structural integrity. In this study, we developed a blend of SF and AT as a printable biomaterial for extrusion-based 3D printing. Using photocrosslinkable SF/AT inks facilitated the fabrication of complex scaffolds with high printability, thereby enhancing their structural stability. The incorporation of silver nitrate facilitated the tunability of mechanical and rheological behaviors. SF/AT scaffolds with varying stiffness in the physiologically relevant range for soft tissues (51-246 kPa) exhibited excellent biocompatibility, indicating their promising potential for diverse applications in tissue engineering.


Asunto(s)
Alginatos , Fibroínas , Impresión Tridimensional , Nitrato de Plata , Andamios del Tejido , Fibroínas/química , Alginatos/química , Andamios del Tejido/química , Nitrato de Plata/química , Animales , Reactivos de Enlaces Cruzados/química , Ingeniería de Tejidos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Reología , Humanos , Ratones , Procesos Fotoquímicos , Tiramina/química
2.
Anal Chem ; 96(4): 1789-1794, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38230634

RESUMEN

Highly sensitive and facile detection of low levels of protein markers is of great significance for the early diagnosis and efficacy monitoring of diseases. Herein, aided by an efficient tyramine-signal amplification (TSA) mechanism, we wish to report a simple but ultrasensitive immunoassay with signal readout on a portable personal glucose meter (PGM). In this study, the bioconjugates of tyramine and invertase (Tyr-inv), which act as the critical bridge to convert and amplify the protein concentration information into glucose, are prepared following a click chemistry reaction. Then, in the presence of a target protein, the sandwich immunoreaction between the immobilized capture antibody, the target protein, and the horseradish peroxidase (HRP)-conjugated detection antibody is specifically performed in a 96-well microplate. Subsequently, the specifically loaded HRP-conjugated detection antibodies will catalyze the amplified deposition of a large number of Tyr-inv molecules onto adjacent proteins through highly efficient TSA. Then, the deposited invertase, whose dosage can faithfully reflect the original concentration of the target protein, can efficiently convert sucrose to glucose. The amount of finally produced glucose is simply quantified by the PGM, realizing the highly sensitive detection of trace protein markers such as the carcinoembryonic antigen and alpha fetoprotein antigen at the fg/mL level. This method is simple, cost-effective, and ultrasensitive without the requirement of sophisticated instruments or specialized laboratory equipment, which may provide a universal and promising technology for highly sensitive immunoassay for in vitro diagnosis of diseases.


Asunto(s)
Técnicas Biosensibles , Glucosa , beta-Fructofuranosidasa/química , Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Anticuerpos , Peroxidasa de Rábano Silvestre/química , Tiramina/química , Oro/química
3.
J Asian Nat Prod Res ; 26(2): 237-247, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37812065

RESUMEN

Three new phenylpropanoid glycosides, piperpubelide (1), 1-propionyl-3-hydroxy-phenyl-4-O-ß-D-glucopyranoside (2), and 1-propionyl-4-hydroxy-phenyl-3-O-ß-D-glucopyranoside (3), a new tyramine-type alkamide, puberulumine L (4), together with thirteen known compounds (5-17) were isolated from Piper puberulum (Benth.) Maxim. Their structures were elucidated by analysis of spectroscopic data involving NMR, IR, UV, and HRESIMS data. Calculated and experimental ECD was used to confirm the configuration of compound 1. Compounds 14, 16, and 17 exhibited relatively positive DPPH radical scavenging activities, with corresponding EC50 of 10.23, 24.12, and 21.83 µM, respectively. In addition, compound 5 inhibited LPS-induced NO production in BV-2 microglia with an IC50 value of 18.05 µM.


Asunto(s)
Glucósidos , Piper , Glucósidos/farmacología , Glucósidos/química , Piper/química , Tiramina/farmacología , Tiramina/química , Estructura Molecular , Glicósidos/farmacología , Glicósidos/química
4.
Angew Chem Int Ed Engl ; 63(2): e202314960, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-37992201

RESUMEN

Herein, we report a novel enzymatic dimerization-induced self-assembly (e-DISA) procedure that converts alanine-tyramine conjugates into highly uniform enzyme-loaded nanoparticles (NPs) or nanocontainers by the action of horseradish peroxidase (HRP) in an aqueous medium under ambient conditions. The NP formation was possible with both enantiomers of alanine, and the average diameter could be varied from 150 nm to 250 nm (with a 5-12 % standard deviation of as-prepared samples) depending on the precursor concentration. About 60 % of the added HRP enzyme was entrapped within the NPs and was subsequently utilized for post-synthetic modification of the NPs with phenolic compounds such as tyramine or tannic acid. One-pot multi-enzyme entrapment of glucose oxidase (GOx) and peroxidase (HRP) within the NPs was also achieved. These GOx-HRP loaded NPs allowed multimodal detection of glucose, including that present in human saliva, with a limit of detection (LoD) of 740 nM through fluorimetry. The NPs exhibited good cytocompatibility and were stable to changes in pH (acidic to basic), temperature, ultrasonication, and even the presence of organic solvent (EtOH) to a certain extent, since they are stabilized by intermolecular hydrogen bonding, π-π, and CH-π interactions. The proposed e-DISA procedure can be widely expanded through the design of diverse enzyme-responsive precursors.


Asunto(s)
Nanopartículas , Tiramina , Humanos , Tiramina/química , Dimerización , Glucosa , Peroxidasa de Rábano Silvestre/química , Glucosa Oxidasa/química
5.
Int J Biol Macromol ; 259(Pt 2): 128843, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38104684

RESUMEN

Hydrogels are receiving increasing attention for their use in 3D cell culture, tissue engineering, and bioprinting applications. Each application places specific mechanical and biological demands on these hydrogels. We developed a hydrogel toolbox based on enzymatically crosslinkable polysaccharides via tyramine (TA) moieties, allowing for rapid and tunable crosslinking with well-defined stiffness and high cell viability. Including gelatin modified with TA moieties (Gel-TA) improved the hydrogels' biological properties; 3 T3 fibroblasts and HUVECs attached to and proliferated on the enriched hydrogels at minute Gel-TA concentrations, in contrast to bare or unmodified gelatin-enriched hydrogels. Moreover, we were able to switch HUVECs from a quiescent to a migratory phenotype simply by altering the ligand concentration, demonstrating the potential to easily control cell fate. In encapsulation studies, Gel-TA significantly improved the metabolic activity of 3 T3 fibroblasts in soft hydrogels. Furthermore, we showed rapid migration and network formation in Gel-TA enriched hydrogels in contrast to a non-migratory behavior in non-enriched polysaccharide hydrogels. Finally, low hydrogel density significantly improves tissue response in vivo with large infiltration and low fibrotic reaction. Further development by adding ECM proteins, peptides, and growth factor adhesion sites will lead to a toolbox for hydrogels tailored toward their desired application.


Asunto(s)
Gelatina , Tiramina , Tiramina/farmacología , Tiramina/química , Gelatina/farmacología , Gelatina/química , Ácido Hialurónico/farmacología , Ácido Hialurónico/química , Dextranos , Hidrogeles/farmacología , Hidrogeles/química , Ingeniería de Tejidos
6.
J Mech Behav Biomed Mater ; 143: 105916, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37224645

RESUMEN

New studies have shown the great potential of the combination of in situ enzymatically cross-linked hydrogels based on tyramine derivative of hyaluronic acid (HA-TA) with platelet-rich plasma (PRP) and platelet lysate in regenerative medicine. This study describes how the presence of PRP and platelet lysate affects the kinetics of gelation, viscoelastic properties, swelling ratio, and the network structure of HA-TA hydrogels and how the encapsulation of PRP in hydrogels affects the bioactivity of released PRP determined as the ability to induce cell proliferation. The properties of hydrogels were tuned by a degree of substitution and concentration of HA-TA derivatives. The addition of platelet derivatives to the reaction mixture slowed down the cross-linking reaction and reduced elastic modulus (G') and thus cross-linking efficiency. However, low-swellable hydrogels (7-190%) suitable for soft tissue engineering with G' 200-1800 Pa were prepared with a gelation time within 1 min. It was confirmed that tested cross-linking reaction conditions are suitable for PRP incorporation because the total bioactivity level of PRP released from HA-TA hydrogels was ≥87% and HA-TA content in the hydrogels and thus mesh size (285-482 nm) has no significant effect on the bioactivity level of released PRP.


Asunto(s)
Ácido Hialurónico , Plasma Rico en Plaquetas , Ácido Hialurónico/química , Hidrogeles/química , Tiramina/análisis , Tiramina/química , Ingeniería de Tejidos , Plasma Rico en Plaquetas/química
7.
Anal Bioanal Chem ; 415(11): 2037-2044, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36759389

RESUMEN

This work details the enzymatic generation of fluorescence nanomaterials and the use of this optical signal as the analytical parameter for the quantification of the substrate. More specifically, fluorescent copper nanoclusters have been obtained during the enzymatic reaction of tyramine oxidase and tyramine in the presence of Cu(II); the fluorescence intensity being proportional to the concentration of tyramine. The nanoclusters obtained show fluorescence at 445 nm by being excited at 320 nm and have been characterized by TEM, EDX, and XPS. The formation mechanism has also been studied, suggesting that under the optimal conditions (0.1 M MES buffer and pH = 6), the formation of the nanoclusters is due to the reducing properties of the product of the enzymatic reaction (p-hydroxybenzaldehyde) in MES buffer. The method shows a linear relationship with the concentration of tyramine in the range from 1.0·10-5 to 2.5·10-4 M, a RSD of 3% (n = 5) and a LOD of 6.3·10-6 M. The method has been applied to the determination of tyramine in sausage with good results.


Asunto(s)
Colorantes Fluorescentes , Nanopartículas del Metal , Cobre/química , Espectrometría de Fluorescencia/métodos , Tiramina/química
8.
Biosens Bioelectron ; 225: 115081, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36680969

RESUMEN

An ultrasensitive electrochemical immunosensor based on signal amplification of the deposition of the electroactive ferrocene-tyramine (Fc-Tyr) molecule, catalyzed by horseradish peroxidase (HRP), was constructed for the detection of the liver cancer marker Glypican-3 (GPC3). Functional electroactive molecule Fc-Tyr is reported to exhibit both the enzymatic cascade catalytic activity of tyramine signal amplification (TSA) and the excellent redox properties of ferrocene. In terms of design, the low matrix effects inherent in using the magnetic bead platforms, a quasi-homogeneous system, allowed capturing the target protein GPC3 without sample pretreatment, and loading HRP to trigger the TSA, which induced a large amount of Fc-Tyr deposited on the electrode surface layer by layer as a signal probe for the detection of GPC3. The concept of Fc-Tyr as an electroactive label was validated, GPC3 biosensor exhibited high selectivity and sensitivity to GPC3 in the range of 0.1 ng mL-1-1 µg mL-1. Finally, the sensor was used simultaneously with ELISA to assess GPC3 levels in the serum of clinical liver cancer patients, and the results showed consistency, with a recovery of 98.33-105.35% and a relative standard deviation (RSD) of 4.38-8.18%, providing a theoretical basis for achieving portable, rapid and point of care testing (POCT) of tumor markers.


Asunto(s)
Técnicas Biosensibles , Neoplasias Hepáticas , Nanopartículas del Metal , Humanos , Inmunoensayo/métodos , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Metalocenos , Glipicanos , Peroxidasa de Rábano Silvestre/química , Neoplasias Hepáticas/diagnóstico , Tiramina/química , Técnicas Electroquímicas , Oro/química , Límite de Detección
9.
Analyst ; 147(24): 5718-5724, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36373550

RESUMEN

A novel surface-enhanced Raman scattering (SERS) immunoassay method based on tyramine signal amplification (TSA) technology triggering the formation of enzyme repeats on an enzyme-linked immunosorbent assay (ELISA) was designed for highly sensitive detection of human chorionic gonadotropin (hCG) using enzymatic biocatalytic precipitation toward o-phenylenediamine (OPD). Initially, a horseradish peroxidase (HRP)-labeled hCG antibody was fixed by the double antibody sandwich method, and then a tyramine-HRP conjugate was used to form HRP repeats by triggering the immobilized HRP on ELISA with the aid of H2O2. In the presence of the target hCG, the HRP repeats carried by the sandwich immune complex catalyzed the oxidation of OPD to produce product molecules with different structures, resulting in changes in the SERS fingerprint spectrum. The analytical performance of the SERS immunoassay was studied in detail using SERS spectral characterization. Under the optimum conditions, the immunosensor displayed a working range from 1 IU L-1 to 16 IU L-1 with a detection limit (LOD) of 0.17 IU L-1 relative to the target hCG. Compared to the traditional SERS immunosensor, a higher detection sensitivity can be obtained. Therefore, this work provides a new strategy for hCG detection and inspiration for the construction of sensitive and efficient immunosensors.


Asunto(s)
Técnicas Biosensibles , Espectrometría Raman , Humanos , Espectrometría Raman/métodos , Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Inmunoadsorbentes , Peroxidasa de Rábano Silvestre/química , Límite de Detección , Peróxido de Hidrógeno , Gonadotropina Coriónica/análisis , Tiramina/química , Oro/química
10.
Biomed Mater ; 18(1)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36322975

RESUMEN

The enzymatically crosslinked hydrogel could replicate the cellular microenvironment for biomedical applications. In the present study, to improve the cytocompatibility of chitosan (CS), sialic acid (SA) was introduced to CS to synthesize sialylated CS (CS-SA), and the tyramine (TA) was grafted to gelatin (G) to obtain TA modified gelatin (G-TA). The successful synthesis of CS-SA and G-TA was confirmed using1H NMR and UV-Vis absorption spectra. The interpenetrating polymer networks G-TA/CS-SA (GC) hydrogel was then fabricated via blending G-TA and CS-SA solutions and crosslinked using horseradish peroxidase. The storage modulus (G') of the fabricated GC hydrogels with different ratios of G-TA/CS-SA greatly varied during the formation and strain of hydrogels. With the increase of CS-SA concentration from 0% to 2%, the storage modulus of GC hydrogels was also observed to decrease from 1500 Pa to 101 Pa; the water uptake capacity of GC hydrogels increased from 1000% to 4500%. Additionally, the cell counting kit-8 and fluorescent images demonstrated the excellent cytocompatibility of GC hydrogels after culturing with NIH 3T3 cells. The obtained results indicated that the fabricated GC hydrogels might have potential in biomedical fields, such as wound dressing.


Asunto(s)
Quitosano , Hidrogeles , Ratones , Animales , Hidrogeles/química , Quitosano/química , Gelatina/química , Tiramina/química , Vendajes
11.
Biomacromolecules ; 23(10): 4254-4267, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36136959

RESUMEN

This work presents a polysaccharide and protein-based two-component hybrid hydrogel integrating the cell-adhesive gelatin-tyramine (G-Tyr) and nonadhesive hyaluronic acid-tyramine (HA-Tyr) through enzyme-mediated oxidative coupling reaction. The resulting HA-Tyr/G-Tyr hydrogel reflects the precise chemical and mechanical features of the cancer extracellular matrix and is able to tune cancer cell adhesion upon switching the component ratio. The cells form quasi-spheroids on HA-Tyr rich hydrogels, while they tend to form an invasive monolayer culture on G-Tyr rich hydrogels. The metastatic genotype of colorectal adenocarcinoma cells (HT-29) increases on G-Tyr rich hydrogels which is driven by the material's adhesive property, and additionally confirmed by the suppressed gene expressions of apoptosis and autophagy. On the other hand, HA-Tyr rich hydrogels lead the cells to necrotic death via oxidative stress in quasi-spheroids. This work demonstrates the ideality of HA-Tyr/G-Tyr to modulate cancer cell adhesion, which also has potential in preventing primary metastasis after onco-surgery, biomaterials-based cancer research, and drug testing.


Asunto(s)
Hidrogeles , Neoplasias , Adhesivos , Materiales Biocompatibles , Gelatina , Humanos , Ácido Hialurónico/química , Hidrogeles/química , Hidrogeles/farmacología , Tiramina/química
12.
Biomolecules ; 11(12)2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34944409

RESUMEN

Natural products are a vital source for agriculture, medicine, cosmetic and other fields. Among them alkylamides are a broad and expanding group found in at least 33 plant families. Frequently, they possess a simple carbon skeleton architecture but show broad structural variability and important properties such as immunomodulatory, antimicrobial, antiviral, larvicidal, insecticidal and antioxidant properties, amongst others. Despite to these several and promising biological activities, up to today, only two reviews have been published on natural alkylamides. One focuses on their potential pharmacology application and their distribution in the plant kingdom and the other one on the bioactive alkylamides specifically found in Annona spp. The present review is focused on the plant bioactive cinnamoyltyramine alkylamides, which are subject of several works reported in the literature. Furthermore, the co-metabolites isolated from the same natural sources and their biological activities are also reported.


Asunto(s)
Annona/química , Cinamatos/química , Fitoquímicos/química , Tiramina/análogos & derivados , Estructura Molecular , Fitoquímicos/farmacología , Tiramina/química
13.
J Nanobiotechnology ; 19(1): 450, 2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-34952586

RESUMEN

Human epidermal growth factor receptor 2 (HER2)-positive exosomes play an extremely important role in the diagnosis and treatment options of breast cancers. Herein, based on the reformative tyramine signal amplification (TSA) enabled by molecular aptamer beacon (MAB) conversion, a label-free surface plasmon resonance (SPR) biosensor was proposed for highly sensitive and specific detection of HER2-positive exosomes. The exosomes were captured by the HER2 aptamer region of MAB immobilized on the chip surface, which enabled the exposure of the G-quadruplex DNA (G4 DNA) that could form peroxidase-like G4-hemin. In turn, the formed G4-hemin catalyzed the deposition of plentiful tyramine-coated gold nanoparticles (AuNPs-Ty) on the exosome membrane with the help of H2O2, generating a significantly enhanced SPR signal. In the reformative TSA system, the horseradish peroxidase (HRP) as a major component was replaced with nonenzymic G4-hemin, bypassing the defects of natural enzymes. Moreover, the dual-recognition of the surface proteins and lipid membrane of the desired exosomes endowed the sensing strategy with high specificity without the interruption of free proteins. As a result, this developed SPR biosensor exhibited a wide linear range from 1.0 × 104 to 1.0 × 107 particles/mL. Importantly, this strategy was able to accurately distinguish HER2-positive breast cancer patients from healthy individuals, exhibiting great potential clinical application.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Exosomas/metabolismo , Resonancia por Plasmón de Superficie , Tiramina/química , Neoplasias de la Mama/diagnóstico , Línea Celular Tumoral , Exosomas/química , G-Cuádruplex , Oro/química , Hemina/química , Humanos , Peróxido de Hidrógeno/química , Límite de Detección , Nanopartículas del Metal/química , Receptor ErbB-2/metabolismo , Reproducibilidad de los Resultados
14.
Mar Drugs ; 19(10)2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-34677432

RESUMEN

Aphrocallistes vastus lectin (AVL) is a C-type marine lectin produced by sponges. Our previous study demonstrated that genes encoding AVL enhanced the cytotoxic effect of oncolytic vaccinia virus (oncoVV) in a variety of cancer cells. In this study, the inhibitory effect of oncoVV-AVL on Hela S3 cervical cancer cells, a cell line with spheroidizing ability, was explored. The results showed that oncoVV-AVL could inhibit Hela S3 cells growth both in vivo and in vitro. Further investigation revealed that AVL increased the virus replication, promote the expression of OASL protein and stimulated the activation of Raf in Hela S3 cells. This study may provide insight into a novel way for the utilization of lection AVL.


Asunto(s)
Adenina/análogos & derivados , Antineoplásicos/farmacología , Lectinas/farmacología , Virus Oncolíticos/patogenicidad , Poríferos , Tiramina/análogos & derivados , Virus Vaccinia/patogenicidad , Adenina/química , Adenina/farmacología , Adenina/uso terapéutico , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Organismos Acuáticos , Proliferación Celular/efectos de los fármacos , Femenino , Células HeLa/efectos de los fármacos , Humanos , Lectinas/química , Lectinas/uso terapéutico , Tiramina/química , Tiramina/farmacología , Tiramina/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico
15.
Adv Mater ; 33(42): e2102660, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34476848

RESUMEN

Cell-matrix interactions govern cell behavior and tissue function by facilitating transduction of biomechanical cues. Engineered tissues often incorporate these interactions by employing cell-adhesive materials. However, using constitutively active cell-adhesive materials impedes control over cell fate and elicits inflammatory responses upon implantation. Here, an alternative cell-material interaction strategy that provides mechanotransducive properties via discrete inducible on-cell crosslinking (DOCKING) of materials, including those that are inherently non-cell-adhesive, is introduced. Specifically, tyramine-functionalized materials are tethered to tyrosines that are naturally present in extracellular protein domains via enzyme-mediated oxidative crosslinking. Temporal control over the stiffness of on-cell tethered 3D microniches reveals that DOCKING uniquely enables lineage programming of stem cells by targeting adhesome-related mechanotransduction pathways acting independently of cell volume changes and spreading. In short, DOCKING represents a bioinspired and cytocompatible cell-tethering strategy that offers new routes to study and engineer cell-material interactions, thereby advancing applications ranging from drug delivery, to cell-based therapy, and cultured meat.


Asunto(s)
Materiales Biocompatibles/química , Mecanotransducción Celular , Animales , Materiales Biocompatibles/metabolismo , Materiales Biocompatibles/farmacología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula , Dextranos/química , Peroxidasa de Rábano Silvestre/metabolismo , Humanos , Hidrogeles/química , Integrinas/metabolismo , Mecanotransducción Celular/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/química , Oxidación-Reducción , Tiramina/química
16.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34361074

RESUMEN

Alzheimer's disease (AD) is a multifactorial neurodegenerative condition of the central nervous system (CNS) that is currently treated by cholinesterase inhibitors and the N-methyl-d-aspartate receptor antagonist, memantine. Emerging evidence strongly supports the relevance of targeting butyrylcholinesterase (BuChE) in the more advanced stages of AD. Within this study, we have generated a pilot series of compounds (1-20) structurally inspired from belladine-type Amaryllidaceae alkaloids, namely carltonine A and B, and evaluated their acetylcholinesterase (AChE) and BuChE inhibition properties. Some of the compounds exhibited intriguing inhibition activity for human BuChE (hBuChE), with a preference for BuChE over AChE. Seven compounds were found to possess a hBuChE inhibition profile, with IC50 values below 1 µM. The most potent one, compound 6, showed nanomolar range activity with an IC50 value of 72 nM and an excellent selectivity pattern over AChE, reaching a selectivity index of almost 1400. Compound 6 was further studied by enzyme kinetics, along with in-silico techniques, to reveal the mode of inhibition. The prediction of CNS availability estimates that all the compounds in this survey can pass through the blood-brain barrier (BBB), as disclosed by the BBB score.


Asunto(s)
Acetilcolinesterasa/química , Alcaloides de Amaryllidaceae/química , Butirilcolinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Simulación del Acoplamiento Molecular , Neuroblastoma/tratamiento farmacológico , Tiramina/análogos & derivados , Proliferación Celular , Inhibidores de la Colinesterasa/química , Simulación por Computador , Humanos , Neuroblastoma/patología , Relación Estructura-Actividad , Células Tumorales Cultivadas , Tiramina/química
17.
J Am Soc Mass Spectrom ; 32(8): 2144-2152, 2021 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-34293862

RESUMEN

Although liquid chromatography-tandem mass spectrometry (LC-MS/MS) equipped with electrospray ionization (ESI) is widely employed for metabolite analysis, substituted phenethylamines commonly undergo fragmentation during ESI in-source collision-induced dissociation (CID). Unexpected fragmentation hampers not only unambiguous identification but also accurate metabolite quantification. ESI in-source CID induces N-Cα bond dissociation in substituted phenethylamines lacking a ß-hydroxy group to produce fragment ions with a spiro[2.5]octadienylium motif. In contrast, phenethylamines with a ß-hydroxy group generate substituted 2-phenylaziridium through ESI in-source CID-induced H2O loss. The fragment ion yield produced by ESI in-source CID can be estimated by the dissociation rate constant and internal energy of the analyte ion, determined by employing density functional theory calculations and the survival yield method using a thermometer ion, respectively. Fragmentation is strongly enhanced by the presence of an ß-hydroxy group, whereas N-methylation suppresses fragmentation. In particular, octopamine and noradrenaline, which contain an ß-hydroxy and primary amine groups, produce more intense fragment ion signals than protonated molecules. Regarding the quantitative analysis of phenethylamines present in the mouse brain, the noradrenaline fragment ion used as the precursor in multiple reaction monitoring (MRM) provided a higher signal-to-noise ratio in the resulting spectra than protonated noradrenaline. The present method allows for the quantitative analysis of substituted phenethylamines with high sensitivity.


Asunto(s)
Neurotransmisores/análisis , Fenetilaminas/análisis , Fenetilaminas/química , Animales , Química Encefálica , Fraccionamiento Químico , Cromatografía Liquida , Dopamina/análisis , Dopamina/química , Masculino , Ratones Endogámicos C57BL , Neurotransmisores/química , Norepinefrina/análisis , Norepinefrina/química , Sensibilidad y Especificidad , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Tiramina/análisis , Tiramina/química
18.
Mikrochim Acta ; 188(8): 270, 2021 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-34302226

RESUMEN

A photoelectrochemical (PEC) biosensor capable of detecting cytokeratin 19 fragment 21-1 (CYFRA21-1) was optimized by taking advantage of the powerful conjugate repeats of horseradish peroxidase and tyramine (HRP-tyramine)-triggered enzymatic biocatalytic precipitation (BCP) on high-performance BiVO4/Ag3VO4/SnS2 photoelectrodes. Compared with the ubiquitous BCP strategy, we identified a design supporting conjugate repeats generated by HRP and tyramine-triggered immeasurable insoluble precipitates in the presence of hydrogen peroxide and 4-chloro-1-phenol (4-CN), and the steric hindrance improved sensitivity. Moreover, by virtue of BiVO4, Ag3VO4, SnS2 excellent level matching structure and chemical stability, a heterojunction (BiVO4/Ag3VO4/SnS2) with high light absorption efficiency has been successfully prepared. The novel heterostructure system of BiVO4/Ag3VO4/SnS2 with high detection current and low background signal exhibited high-performance PEC determination. Generally, the hitherto untapped biosensor resource realized the sensitive detection of CYFRA21-1 with a wide linear range from 50 fg/mL to 200 ng/mL, and a detection limit of 15 fg/mL, which illustrated the potential for biotechnological applications.


Asunto(s)
Antígenos de Neoplasias/sangre , Peroxidasa de Rábano Silvestre/química , Inmunoensayo/métodos , Queratina-19/sangre , Tiramina/química , Anticuerpos Inmovilizados/inmunología , Antígenos de Neoplasias/inmunología , Armoracia/enzimología , Bismuto/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Enzimas Inmovilizadas/química , Humanos , Inmunoensayo/instrumentación , Queratina-19/inmunología , Límite de Detección , Nanosferas/química , Reproducibilidad de los Resultados , Dióxido de Silicio/química , Compuestos de Plata/química , Sulfuros/química , Compuestos de Estaño/química , Vanadatos/química
19.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34298939

RESUMEN

The present study deals with the mathematical modeling of crosslinking kinetics of polymer-phenol conjugates mediated by the Horseradish Peroxidase (HRP)-hydrogen peroxide (H2O2) initiation system. More specifically, a dynamic Monte Carlo (MC) kinetic model is developed to quantify the effects of crosslinking conditions (i.e., polymer concentration, degree of phenol substitution and HRP and H2O2 concentrations) on the gelation onset time; evolution of molecular weight distribution and number and weight average molecular weights of the crosslinkable polymer chains and gel fraction. It is shown that the MC kinetic model can faithfully describe the crosslinking kinetics of a finite sample of crosslinkable polymer chains with time, providing detailed molecular information for the crosslinkable system before and after the gelation point. The MC model is validated using experimental measurements on the crosslinking of a tyramine modified Hyaluronic Acid (HA-Tyr) polymer solution reported in the literature. Based on the rubber elasticity theory and the MC results, the dynamic evolution of hydrogel viscoelastic and molecular properties (i.e., number average molecular weight between crosslinks, Mc, and hydrogel mesh size, ξ) are calculated.


Asunto(s)
Ácido Hialurónico/química , Tiramina/química , Elasticidad , Peroxidasa de Rábano Silvestre/química , Hidrogeles/química , Peróxido de Hidrógeno/química , Cinética , Modelos Teóricos , Método de Montecarlo , Polímeros/química , Reología
20.
J Mater Chem B ; 9(20): 4211-4218, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-33998627

RESUMEN

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by joint inflammation. Since the inflammatory condition plays an important role in the disease process, it is important to develop and test new therapeutic approaches that specifically target and treat joint inflammation. In this study, a human 3D inflammatory cartilage-on-a-chip model was established to test the therapeutic efficacy of anti-TNFα mAb-CS/PAMAM dendrimer NPs loaded-Tyramine-Gellan Gum in the treatment of inflammation. The results showed that the proposed therapeutic approach applied to the human monocyte cell line (THP-1) and human chondrogenic primary cells (hCH) cell-based inflammation system revealed an anti-inflammatory capacity that increased over 14 days. It was also possible to observe that Coll type II was highly expressed by inflamed hCH upon the culture with anti-TNF α mAb-CS/PAMAM dendrimer NPs, indicating that the hCH cells were able maintain their biological function. The developed preclinical model allowed us to provide more robust data on the potential therapeutic effect of anti-TNF α mAb-CS/PAMAM dendrimer NPs loaded-Ty-GG hydrogel in a physiologically relevant model.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Materiales Biocompatibles/uso terapéutico , Dendrímeros/uso terapéutico , Dispositivos Laboratorio en un Chip , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Anticuerpos Monoclonales/química , Artritis Reumatoide/tratamiento farmacológico , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Células Cultivadas , Dendrímeros/síntesis química , Dendrímeros/química , Humanos , Hidrogeles/química , Inflamación/tratamiento farmacológico , Nanopartículas/química , Polisacáridos Bacterianos/química , Inhibidores del Factor de Necrosis Tumoral/síntesis química , Inhibidores del Factor de Necrosis Tumoral/química , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Tiramina/química
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