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1.
Anal Chem ; 95(13): 5678-5686, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36952638

RESUMO

Sensing systems based on cholinesterase and carboxylesterase coupled with different transduction technologies have emerged for pesticide screening owing to their simple operation, fast response, and suitability for on-site analysis. However, the broad spectrum and specificity screening of pyrethroids over organophosphates and carbamates remains an unmet challenge for current enzymatic sensors. Human serum albumin (HSA), a multifunctional protein, can promote various chemical transformations and show a high affinity for pyrethroids, which offer a route for specific and broad-spectrum pyrethroid screening. Herein, for the first time, we evaluated the catalytic hydrolysis function of human serum albumin (HSA) on the coumarin lactone bond and revealed that HSA can act as an enzyme to catalyze the hydrolysis of the coumarin lactone bond. Molecular docking and chemical modifications indicate that lysine 199 and tyrosine 411 serve as the catalytic general base and contribute to most of the catalytic activity. Utilizing this enzymatic activity, a broad specific ratiometric fluorescence pyrethroids sensing system was developed. The binding energetics and binding constants of pesticides and HSA show that pyrethroids bind to HSA more easily than organophosphates and carbamates, which is responsible for the specificity of the sensing system. This study provides a general sensor platform and strategy for screening pesticides and reveals the catalytic activity of HSA on the hydrolysis of the coumarin lactone bond, which may open innovative horizons for the chemical sensing and biomedical applications of HSA.


Assuntos
Praguicidas , Piretrinas , Humanos , Albumina Sérica Humana/metabolismo , Hidrólise , Piretrinas/química , Simulação de Acoplamento Molecular , Cumarínicos/química , Carbamatos , Organofosfatos , Lactonas , Ligação Proteica , Espectrometria de Fluorescência
2.
J Mol Recognit ; 34(6): e2889, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33646596

RESUMO

In this paper, the effects of three isoflavones including daidzein, genistein, and puerarin on fibrillation of hen egg-white lysozyme were investigated by various analytical methods. The results demonstrated that all isoflavones could effectively inhibit the fibrillogenesis of hen egg-white lysozyme and destabilized the preformed fibrils of hen egg-white lysozyme in a dose-dependent manner. To further understand the inhibition mechanism, molecular modeling was carried out. The docking results demonstrated that the isoflavones could bind to two key fibrogenic sites in hen egg-white lysozyme through van der Waals force, electrostatic forces, and hydrogen bonding, as well as σ-π stacking. By these means, isoflavones could not only obviously enhance the hydrophobicity of the binding sites, but also greatly stabilize the native state of HEWL, which was able to postpone the fibrosis process of hen egg-white lysozyme.


Assuntos
Galinhas/metabolismo , Fibrose/metabolismo , Isoflavonas/farmacologia , Muramidase/metabolismo , Animais , Sítios de Ligação/efeitos dos fármacos , Ligação de Hidrogênio/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Modelos Moleculares , Simulação de Acoplamento Molecular/métodos , Ligação Proteica/efeitos dos fármacos , Eletricidade Estática
3.
Bioorg Med Chem Lett ; 40: 127913, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33705905

RESUMO

Resveratrol is a natural polyhydroxy trans-stilbene product with many biological activities. One of the most striking biological activities of it is its anti-aging potential. Resveratrol can exhibit anti-aging activity via a variety of signaling pathways, however, the repair effect of it on kidney and brain injury in aging mice induced by d-galactose and its regulation on klotho gene expression have not been reported. Herein, the anti-aging activity of resveratrol and its effect on the repair of kidney and brain injuries in d-galactose-induced aging mice, as well as its regulation of klotho gene expression in these two tissues were investigated. The results indicated that resveratrol could significantly increase the aged cell viability and improve the pathological status of aging mice via inhibiting the formation of malondialdehyde and enhancing the activities of superoxide dismutase and catalase. The histological analysis suggested that resveratrol could remarkably repair the damages of kidney and brain tissues in aging mice. Moreover, PCR and western blot have shown that resveratrol could obviously increase the anti-aging klotho gene expression in the above tissues. The data in this paper further revealed and enriched the anti-aging mechanism of resveratrol, and the methods established in this study can be used as a tool to evaluate the anti-aging activity of drugs to a certain extent.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/química , Lesões Encefálicas/tratamento farmacológico , Insuficiência Renal/tratamento farmacológico , Resveratrol/química , Animais , Antioxidantes/farmacologia , Encéfalo , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Galactose/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Glucuronidase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Rim , Proteínas Klotho , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Transdução de Sinais , Superóxido Dismutase/metabolismo
4.
Anal Chem ; 92(24): 16130-16137, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33237734

RESUMO

As vital important bioactive species, human serum albumin (HSA) and sulfur dioxide (SO2) are essential molecules in the organisms and act a pivotal part in many biological events. Although studies have shown that SO2-induced HSA radicals can cause oxidative damage, the underlying mechanism of the synergistic effect of HSA and SO2 in various diseases is obscure, mainly because of the lack of powerful tools that can simultaneously detect HSA and SO2 in living systems. In this work, we report a novel single-site, double-sensing fluorescent probe 1 for the simultaneous detection of HSA and SO2. The probe is based on our finding that HSA can catalyze a Michael addition reaction between the probe and SO2, which induces a change in fluorescence. Probe 1 can effectively entered the endoplasmic reticulum and can be used to image exogenously introduced and de novo synthesis of HSA in endoplasmic reticulum. Furthermore, the simultaneous detection of HSA and SO2 was realized for the first time with probe 1. More important, we observed that HSA still retains its activity to catalyze the Michael addition reaction of 1 and SO2 in living cells, which may provide a significant boost in the study of the role of HSA in medicine and pharmacy.


Assuntos
Albumina Sérica Humana/análise , Dióxido de Enxofre/análise , Catálise , Sobrevivência Celular , Corantes Fluorescentes/química , Células HeLa , Humanos , Albumina Sérica Humana/química , Albumina Sérica Humana/urina , Dióxido de Enxofre/química , Dióxido de Enxofre/urina
5.
J Mol Recognit ; 30(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27670268

RESUMO

In this study, the fibrillation of hen egg-white lysozyme (HEWL) in the absence and presence of different concentrations of silybin was studied by thioflavin T spectroscopy, Congo red binding assays, 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence assay, circular dichroism, and transmission electron microscopy. The experimental results indicated that not only the fibrillation of HEWL at high temperature (65°C) and low pH (pH = 2.0) could be inhibited effectively by silybin but also the inhibition of HEWL by silybin followed a dose-dependent manner. Molecular docking studies indicated that 2 possible binding modes could be found in the interaction between silybin and HEWL via van der Waals forces and electrostatic forces as well as hydrogen bonding. One of these 2 conformations was directly entered into the cavity of HEWL (binding site I); the other was bound to the surface of HEWL (binding site II). In this way, silybin could not only increase the hydrophobicity of the cavity or the surface of HEWL but also influence the microenvironment of the binding site, which was able to stabilize the structure of HEWL and delay the process of HEWL fibrosis.


Assuntos
Muramidase/química , Muramidase/efeitos dos fármacos , Silimarina/farmacologia , Animais , Sítios de Ligação , Dicroísmo Circular , Relação Dose-Resposta a Droga , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Silibina , Silimarina/química
6.
J Mol Recognit ; 29(10): 476-84, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27135781

RESUMO

In this study, the molecular interactions between pepsin and three pyrethroid insecticides, including fenvalerate, cyhalothrin and deltamethrin, were investigated by multi-spectroscopic and molecular docking methods under mimic physiological pH conditions. The results indicated that all of these insecticides could interact with pepsin to form insecticide-pepsin complexes. The binding constants, number of binding sites and thermodynamic parameters measured at different temperatures indicated that these three pyrethroid insecticides could spontaneously bind with pepsin mainly through electrostatic forces and hydrophobic interactions with one binding site. According to the theory of Föster's non-radioactive energy transfer, the distance (r) between pepsin and three pyrethroid insecticides were all found to be less than 7 nm, which implied that the energy transfer occurred between pepsin and these insecticides, leading to the quenching of pepsin fluorescence. Synchronous and three-dimensional fluorescence, CD spectra and molecular docking results indicated that all tested pyrethroid insecticides bound directly into the enzyme cavity site and the binding of insecticides into the cavity influenced the microenvironment of the pepsin activity site which resulted in the extension of peptide strands of pepsin with loss of α-helix structures.Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Inseticidas/metabolismo , Pepsina A/química , Pepsina A/metabolismo , Piretrinas/metabolismo , Sítios de Ligação , Dicroísmo Circular , Transferência de Energia , Interações Hidrofóbicas e Hidrofílicas , Inseticidas/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Nitrilas/química , Nitrilas/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Piretrinas/química , Espectrometria de Fluorescência , Eletricidade Estática
7.
J Fluoresc ; 25(4): 941-59, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26006100

RESUMO

In the work described on this paper, the interactions between eight flavonoids and hyaluronidase (HAase), an important enzyme involved in a promoting inflammation pathway, were investigated by spectroscopic and molecular modeling methods. The results revealed that all flavonoids could interact with HAase to form flavonoid-HAase complexes. The binding parameters obtained from the data at different temperatures indicated that flavonoids could spontaneously bind with HAase mainly through electrostatic forces and hydrophobic interactions with one binding site. According to synchronous and three-dimensional fluorescence spectra and the molecular docking results, all flavonoids bound directly into the enzyme cavity site and the binding of flavonoid into the enzyme cavity influenced the microenvironment of the HAase activity site which led to the reduced enzyme activity. The present study provides direct evidence at a molecular level to understand the mechanism of inhibitory effect of flavonoid against HAase and explain the anti-inflammatory mechanism of the Traditional Chinese Medicines as anti-inflammatory drugs.


Assuntos
Flavonoides/química , Hialuronoglucosaminidase/química , Simulação de Acoplamento Molecular , Sítios de Ligação , Fenômenos Biofísicos , Dicroísmo Circular , Flavonoides/metabolismo , Humanos , Hialuronoglucosaminidase/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Eletricidade Estática
8.
Luminescence ; 30(2): 124-30, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25044877

RESUMO

A simple, rapid and sensitive method for the determination of atomoxetine hydrochloride (AH) by capillary electrophoresis with electrochemiluminescence detection (CE-ECL) using tris(2,2'-bipyridyl) ruthenium (II) was developed. Under optimized conditions, the determinations of AH in capsules and rat plasmas and the study on its interactions with three plasma proteins, including bovine serum albumin, cytochrome c and myoglobin were performed successfully. Relative to some previous studies, in this paper the methodologies for the determination of AH in aqueous solution and spiked plasma systems were established, respectively. By comparing the difference between the two work curves of two systems, the matrix effect in plasma samples on the determination of AH by the CE-ECL method was discussed in detail. The results indicated that the effect of the matrix in plasma samples should not be ignored even if no obvious interference was found in the electropherograms and the establishment of method validation in complex samples by the CE-ECL method was necessary.


Assuntos
Cloridrato de Atomoxetina/análise , Citocromos c/química , Técnicas Eletroquímicas , Luminescência , Mioglobina/química , Soroalbumina Bovina/química , Animais , Bovinos , Eletroforese Capilar , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
9.
J Fluoresc ; 24(4): 1031-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24789771

RESUMO

In this study, the binding mode of nobiletin (NOB) with pepsin was investigated by spectroscopic and molecular docking methods. NOB can interact with pepsin to form a NOB-pepsin complex. The binding constant, number of binding sites and thermodynamic parameters were measured, which indicated that NOB could spontaneously bind with pepsin through hydrophobic and electrostatic forces with one binding site. Molecular docking results revealed that NOB bound into the pepsin cavity. Synchronous and three-dimensional fluorescence spectra results provide data concerning conformational and some micro-environmental changes of pepsin. Furthermore, the binding of NOB can inhibit pepsin activity in vitro. The present study provides direct evidence at a molecular level to show that NOB could induce changes in the enzyme pepsin structure and function.


Assuntos
Flavonas/química , Simulação de Acoplamento Molecular , Pepsina A/química , Estrutura Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
10.
Luminescence ; 29(7): 715-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24339327

RESUMO

The interaction of pepsin with chlorogenic acid (CHA) was investigated using fluorescence, UV/vis spectroscopy and molecular modeling methods. Stern-Volmer analysis indicated that the fluorescence quenching of pepsin by CHA resulted from a static mechanism, and the binding constant was 1.1846 × 10(5) and 1.1587 × 10(5) L/mol at 288 and 310 K, respectively. The distance between donor (pepsin) and acceptor (CHA) was calculated to be 2.39 nm and the number of binding sites for CHA binding on pepsin was ~ 1. The results of synchronous fluorescence and three-dimensional fluorescence showed that binding of CHA to pepsin could induce conformational changes in pepsin. Molecular docking experiments found that CHA bonded with pepsin in the area of the hydrophobic cavity with Van der Waals' forces or hydrogen bonding interaction, which were consistent with the results obtained from the thermodynamic parameter analysis. Furthermore, the binding of CHA can inhibit pepsin activity in vitro.


Assuntos
Ácido Clorogênico/química , Simulação de Acoplamento Molecular , Pepsina A/química , Sítios de Ligação , Fluorescência , Estrutura Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 319: 124566, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833890

RESUMO

Nitrite (NO2-) widely exists in our daily diet, and its excessive consumption can lead to detrimental effects on the human central nervous system and an elevated risk of cancer. The fluorescence probe method for the determination of nitrite has developed rapidly due to its simplicity, rapidity and sensitivity. Despite establishing various nitrite sensing platforms to ensure the safety of foods and drinking water, the simultaneous achievement of rapid, specific, affordable, visualizing, and on-site nitrite detection remains challenging. Here, we designed a novel fluorescent probe by using Rhodamine 800 as the fluorescent skeleton and 5-aminoindole as the specific reaction group to solve this problem. The probe shows a maximal fluorescence emission at 602 nm, thereby avoiding background emission interference when applied to food samples. Moreover, this unique probe exhibited excellent sensing capabilities for detecting nitrite. These included: a rapid response time within 3 min, a noticeable color change that the naked eye can observe, a low detection limit of 13.8 nM, and a remarkable selectivity and specificity to nitrite. Besides that, the probe can detect nitrite quantitatively in barreled drinking water, ham sausage, and pickles samples, with good recoveries ranging from 89.0 % to 105.8 %. More importantly, based on the probe fixation and signal processing technology, a portable and smart sensing platform was fabricated and made convenient and rapid analysis the content of NO2- in real samples possible. The results obtained in this work provide a new strategy for the design of high-performance nitrite probes and feasible technology for portable, rapid and visual detection of nitrite, and this probe holds the potential as a practical tool for alleviating concern regarding nitrite levels.


Assuntos
Corantes Fluorescentes , Indóis , Limite de Detecção , Nitritos , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Nitritos/análise , Indóis/química , Água Potável/análise , Humanos , Produtos da Carne/análise
12.
Front Endocrinol (Lausanne) ; 14: 1221060, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854190

RESUMO

Background: Tertiary hyperparathyroidism (THPT) is a peculiar subtype of hyperparathyroidism that usually develops from chronic kidney disease (CKD) and persists even after kidney transplantation. Unlike its precursor, secondary hyperparathyroidism (SHPT), THPT is characterized by uncontrolled high levels of calcium in the blood, which suggests the monoclonal or oligoclonal proliferation of parathyroid cells. However, the molecular abnormalities leading to THPT have not yet been fully understood. Methods: In this study, we analyzed DNA samples from hyperplastic parathyroid and corresponding blood cells of 11 patients with THPT using whole-exome sequencing (WES). We identified somatic single nucleotide variants (SNV) and insertions or deletions variants (INDEL) and performed driver mutation analysis, KEGG pathway, and GO functional enrichment analysis. To confirm the impact of selected driver mutated genes, we also tested their expression level in these samples using qRT-PCR. Results: Following quality control and mutation filtering, we identified 17,401 mutations, comprising 6690 missense variants, 3078 frameshift variants, 2005 stop-gained variants, and 1630 synonymous variants. Copy number variants (CNV) analysis showed that chromosome 22 copy number deletion was frequently observed in 6 samples. Driver mutation analysis identified 179 statistically significant mutated genes, including recurrent missense mutations on TBX20, ATAD5, ZNF669, and NOX3 genes in 3 different patients. KEGG pathway analysis revealed two enriched pathways: non-homologous end-joining and cell cycle, with a sole gene, PRKDC, involved. GO analysis demonstrated significant enrichment of various cellular components and cytobiological processes associated with four genes, including GO items of positive regulation of developmental growth, protein ubiquitination, and positive regulation of the apoptotic process. Compared to blood samples, THPT samples exhibited lower expression levels of PRKDC, TBX20, ATAD5, and NOX3 genes. THPT samples with exon mutations had relatively lower expression levels of PRKDC, TBX20, and NOX3 genes compared to those without mutations, although the difference was not statistically significant. Conclusion: This study provides a comprehensive landscape of the genetic characteristics of hyperplastic parathyroids in THPT, highlighting the involvement of multiple genes and pathways in the development and progression of this disease. The dominant mutations identified in our study depicted new insights into the pathogenesis and molecular characteristics of THPT.


Assuntos
População do Leste Asiático , Hiperparatireoidismo , Humanos , Sequenciamento do Exoma , Hiperparatireoidismo/etiologia , Hiperparatireoidismo/genética , Mutação , Glândulas Paratireoides , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/genética
13.
J Fluoresc ; 22(6): 1449-59, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22772804

RESUMO

In this work, the interactions of twelve structurally different flavonoids with Lysozyme (Lys) were studied by fluorescence quenching method. The interaction mechanism and binding properties were investigated. It was found that the binding capacities of flavonoids to Lys were highly depend on the number and position of hydrogen, the kind and position of glycosyl. To explore the selectivity of the bindings of flavonoids with Lys, the structure descriptors of the flavonoids were calculated under QSAR software package of Cerius2, the quantitative relationship between the structures of flavonoids and their binding activities to Lys (QSAR) was performed through genetic function approximation (GFA) regression analysis. The QSAR regression equation was K(A) = 37850.460 + 1630.01Dipole +3038.330HD-171.795MR. (r = 0.858, r(CV)(2) = 0.444, F((11,3)) = 7.48), where K(A) is binding constants, Dipole, HD and MR was dipole moment, number of hydrogen-bond donor and molecular refractivity, respectively. The obtained results make us understand better how the molecular structures influencing their binding to protein which may open up new avenues for the design of the most suitable flavonoids derivatives with structure variants.


Assuntos
Flavonoides/química , Flavonoides/metabolismo , Muramidase/metabolismo , Relação Quantitativa Estrutura-Atividade , Animais , Sítios de Ligação , Transferência de Energia , Ligação Proteica , Espectrometria de Fluorescência
14.
Int J Biol Macromol ; 195: 237-245, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896474

RESUMO

In present study, a novel glutathione functionalized MoS2 quantum dots (GSH-MoS2 QDs) was synthesized from sodium molybdate dehydrate and glutathione by using a one-pot hydrothermal method. After they were characterized, the influence of GSH-MoS2 QDs on amyloid aggregation of bovine serum albumin (BSA) was investigated by various analytical methods including thioflavin T fluorescence assay, circular dichroism and transmission electron microscope. Moreover, the effect of GSH-MoS2 QDs on cytotoxicity induced by BSA amyloid fibrils and cell penetration were evaluated by MTT assay and confocal fluorescence imaging, respectively. The results indicated that the GSH-MoS2 QDs not only had good water solubility, excellent biocompatibility and low cytotoxicity, but also could obviously inhibit the aggregation of BSA and depolymerize the formed BSA aggregates. The data obtained from this work demonstrated that the GSH-MoS2 QDs is expected to become a candidate drug for the treatment of amyloid-related diseases.


Assuntos
Dissulfetos/química , Glutationa/química , Molibdênio/química , Pontos Quânticos/química , Corantes Fluorescentes , Glutationa/sangue , Glutationa/metabolismo , Imagem Óptica/métodos , Agregados Proteicos/fisiologia , Soroalbumina Bovina/química , Espectrometria de Fluorescência/métodos
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 281: 121590, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35850043

RESUMO

A group of 5-methylsalicylaldehyde thiosemicarbazone derivatives (HMTs) bearing different lipophilic and steric substituents attached at the 3-position of cresol ring were synthesized and investigated as mushroom tyrosinase (TYR) inhibitors. The ability of HMTs to inhibit the diphenolase activity of TYR was evaluated with L-DOPA as substrate by determining IC50 values in relation to their structure modifications. HMTs displayed distinct inhibitory competencies towards TYR activity with IC50 values in the range of 1.02-143.56 µM. A close correlation between their inhibition potency and both lipophilicity and molecular size was observed. The inhibitory effect of the hydroxyethyl-containing derivatives was much higher than the hydroxyethyl-free ones overall. Among them, HMT-NBO exhibited the most potent effect with IC50 of 5.85 µM, which was nearly 25-fold and 3.8-fold lower than its parent HMT-NBE and the control kojic acid, respectively. The hydroxyethyl clearly benefited the improvement of the inhibitory competences and acted as a regulating group of lipophilicity of the inhibitors. The kinetic analyses showed that HMTs were reversible and mixed type inhibitors against mushroom TYR. The inhibition mechanism was studied by means of fluorescence spectroscopy, FT-IR, ESI-MS and molecular docking analysis. The results indicated that the observed inhibitory effect of HMTs was accomplished by acting on the amino acid residues rather than by chelating the centre copper ions of TYR. Each of HMTs can insert the hydrophobic pocket and interact with the residues of TYR through Van der Waals forces and hydrogen bonds, with additional electrostatic interactions for HMT-NEE and HMT-NEO further strengthening the affinity. Meanwhile, the inhibitors were observed to bind with L-DOPA or/and L-DOPAquinone forming 1:1 stoichiometric complexes, probably exerting indirect inhibition against TYR activity.


Assuntos
Agaricales , Tiossemicarbazonas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Levodopa , Simulação de Acoplamento Molecular , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Tiossemicarbazonas/farmacologia
16.
Front Endocrinol (Lausanne) ; 13: 1065410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531472

RESUMO

Background: Hypothyroidism is a common hormone deficiency disorder. Although hormone supplemental therapy can be easily performed by daily levothyroxine administration, a proportion of patients suffer from persisting complaints due to unbalanced hormone levels, leaving room for new therapeutic strategies, such as tissue engineering and regenerative medicine. Methods: Electronic searches of databases for studies of thyroid regeneration or thyroid organoids were performed. A systematic review including both in vitro and in vivo models of thyroid regenerative medicine was conducted. Results: Sixty-six independent studies published between 1959 and May 1st, 2022 were included in the current systematic review. Among these 66 studies, the most commonly involved species was human (19 studies), followed by mouse (18 studies), swine (14 studies), rat (13 studies), calf/bovine (4 studies), sheep/lamb (4 studies) and chick (1 study). In addition, in these experiments, the most frequently utilized tissue source was adult thyroid tissue (46 studies), followed by embryonic stem cells (ESCs)/pluripotent stem cells (iPSCs) (10 studies), rat thyroid cell lines (7 studies), embryonic thyroid tissue (2 studies) and newborn or fetal thyroid tissue (2 studies). Sixty-three studies reported relevant thyroid follicular regeneration experiments in vitro, while 21 studies showed an in vivo experiment section that included transplanting engineered thyroid tissue into recipients. Together, 12 studies were carried out using 2D structures, while 50 studies constructed 3D structures. Conclusions: Each aspect of thyroid regenerative medicine was comprehensively described in this review. The recovery of optimal hormonal equilibrium by the transplantation of an engineered functional thyroid holds great therapeutic promise.


Assuntos
Hipotireoidismo , Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Humanos , Ovinos , Bovinos , Camundongos , Ratos , Suínos , Hipotireoidismo/tratamento farmacológico , Hormônios
17.
Luminescence ; 26(5): 368-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21547999

RESUMO

A simple and sensitive flow injection-chemiluminescence (FI-CL) method has been developed for the determination of puerarin, based on the fact that puerarin can greatly inhibit CL of the luminol-H2O2-haemoglobin system. The inhibition of CL intensity was linear to the logarithm of the concentration of puerarin in the range 0.08-10.0 µg/mL (r² = 0.9912). The limit of detection was 0.05 µg/mL (3σ) and the relative standard deviation (RSD) for 1.0 µg/mL (n = 11) of puerarin solution was 1.4%. Coupled with solid-phase extraction (SPE) as the sample pretreatment, the determination of puerarin in biological samples and a preliminary pharmocokinetic study of puerarin in rats were performed. The recoveries for plasma and urine at three different concentrations were 89.2-110.0% and 91.4-104.8%, respectively. The pharmacokinetics of puerarin in plasma of rat coincides with the two-compartment open model. The T(½α) , T(½ß) , CL/F, V(Z/F), AUC(0₋t), MRT0₋∞, T(max) and C(max) were 0.77 ± 0.21 h, 7.55 ± 2.64 h, 2.43 ± 1.02 L/kg/h, 11.40 ± 3.45 L/kg, 56.67 ± 10.65 mg/h/L, 5.04 ± 2.78 h, 1.00 ± 0.35 h and 19.70 ± 4.67 µg/mL, respectively.


Assuntos
Medicamentos de Ervas Chinesas/análise , Análise de Injeção de Fluxo/métodos , Isoflavonas/análise , Medições Luminescentes/métodos , Animais , Medicamentos de Ervas Chinesas/farmacocinética , Humanos , Isoflavonas/sangue , Isoflavonas/farmacocinética , Isoflavonas/urina , Limite de Detecção , Masculino , Pueraria/química , Ratos , Ratos Sprague-Dawley
18.
Luminescence ; 26(5): 374-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21809433

RESUMO

A tris(2,2-bipyridyl)ruthenium(II) (Ru(bpy)3²âº)-based electrochemiluminescence (ECL) detection coupled with capillary electrophoresis (CE) method has been established for the sensitive determination of ephedrine for the first time. Under the optimized conditions [ECL detection at 1.15 V, 25 mmol/L phosphate buffer solution (PBS), pH 8.0, as running buffer, separation voltage 12.5 kV, 5 mmol/L Ru(bpy)3²âº with 60 mmol/L PBS, pH 8.5, in the detection cell] linear correlation (r = 0.9987) between ECL intensity and ephedrine concentration was obtained in the range 6.0 × 10⁻8-6.0 × 10⁻6 g/mL. The detection limit was 4.5 × 10⁻9 g/mL (S:N = 3). The developed method was successfully applied to the analysis of ephedrine in human urine and the investigation of its interactions with three proteins, including bovine serum albumin (BSA), cytochrome C (Cyt-C) and myoglobin (Mb). The number of binding sites and the binding constants between ephedrine and BSA, Cyt-C and Mb were 8.52, 12.60, 10.66 and 1.55 × 104 mol/L, 6.58 × 10³ mol/L and 1.59 × 104 mol/L, respectively.


Assuntos
Citocromos c/química , Medicamentos de Ervas Chinesas/química , Eletroforese Capilar/métodos , Efedrina/química , Medições Luminescentes/métodos , Mioglobina/química , Soroalbumina Bovina/química , Animais , Bovinos , Ephedra/química , Efedrina/urina , Humanos , Limite de Detecção , Ligação Proteica
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119405, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33450449

RESUMO

Resveratrol and oxyresveratrol are two natural polyhydroxy trans-stilbene products. Previous studies have shown that both of them can effectively inhibit the activity of tyrosinase. However, little attention has been paid to study the difference of their inhibitory mechanism. To reveal this difference, in this work a comparative study on the inhibitory effects of resveratrol and oxyresveratrol against cellular tyrosinase activity and melanin content were investigated by B16F0 cells, and the inhibitory mechanism of them on tyrosinase was revealed by cell-free tyrosinase inhibition, intrinsic fluorescence spectrum, circular dichroism and molecular docking. The results showed that the inhibitory capacity of oxyresveratrol toward tyrosinase activity and melanin formation was better than that of resveratrol. The difference of their inhibitory mechanism may be closely related to the different types of inhibition, the different strength of their interaction with tyrosinase and the different number of hydrogen bonds between them. The data in this study provide a scientific basis for revealing the inhibitory mechanisms of resveratrol and oxyresveratrol toward tyrosinase, and lay an experimental foundation for further development and utilization of them.


Assuntos
Monofenol Mono-Oxigenase , Estilbenos , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Extratos Vegetais , Resveratrol/farmacologia , Estilbenos/farmacologia
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 237: 118387, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32416513

RESUMO

In this study, the effect of a glycoprotein obtained from Fupenzi (FPZ) (Rubus chingii Hu.) on the fibrillation of bovine serum album (BSA) was investigated by multi-spectroscopic methods and transmission electron microscopy. Moreover, the cytotoxicity of the glycoprotein and the effect of it on H2O2-induced cell viability were investigated by cell counting kit and ß-galactosidase kit, respectively. The experimental results indicated that the glycoprotein showed very low toxicity to NRK-52E cells and could obviously delay cell senescence and improve cell viability. Moreover, the glycoprotein could effectively inhibit the formation of BSA fibrils and destroy the stability of preformed BSA fibrils in a concentration-dependent manner. Generally, antioxidant capacities are thought to be related to the anti-amyloidogenic activity of inhibitors; therefore, to reveal the inhibitory mechanism, the anti-oxidative property of the glycoprotein was examined by DPPH and ABTS assays. The results demonstrated that FPZ glycoprotein had a remarkable antioxidant activity and the IC50 values of DPPH and ABTS were 0.249 mg mL-1 and 0.092 mg mL-1, respectively. This work suggested that the FPZ glycoprotein had the potential to be designed a new therapeutic agent for attenuating aging and preventing the age-related diseases.


Assuntos
Glicoproteínas/química , Rubus/química , Soroalbumina Bovina/química , Amiloide/química , Amiloide/metabolismo , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Glicoproteínas/toxicidade , Peróxido de Hidrogênio/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Estrutura Secundária de Proteína , Ratos
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