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1.
Anal Bioanal Chem ; 414(2): 867-884, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34581827

RESUMO

C-reactive protein (CRP), a non-specific acute-phase indicator of inflammation, has been widely recognized for its value in clinical diagnostic applications. With the advancement of testing technologies, there have been many reports on fast, simple, and reliable methods for CRP testing. Among these, the aptamer-based biosensors are the focus and hotspot of research for achieving high-sensitivity analysis of CRP. This review summarizes the progress of in vitro aptamer screening for CRP and the recent advances in aptamer-based CRP sensor applications, thus developing insight for the new CRP aptasensor design strategy.


Assuntos
Aptâmeros de Nucleotídeos/química , Proteína C-Reativa/análise , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Humanos , Técnicas Analíticas Microfluídicas/métodos , Óptica e Fotônica/métodos , Reprodutibilidade dos Testes , Técnica de Seleção de Aptâmeros/métodos , Ressonância de Plasmônio de Superfície/métodos
2.
J Sep Sci ; 44(9): 1866-1874, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33646632

RESUMO

In this work, a new quantitative analysis method of multi-components analysis via a single marker strategy coupled with high-performance liquid chromatography (HPLC) analysis, was proposed to analyze nine nucleosides (cytidine, uridine, 2'-deoxyuridine, inosine, guanosine, 2'-deoxyguanosine, thymidine, adenosine, and 2'-deoxyadenosine) as quality control markers in Rhizoma Paridis. Guanosine was set as the internal reference substance, whose content in Rhizoma Paridis was determined using conventional external standard method. Then, relative correction factors between guanosine and the other eight nucleosides were measured respectively. The amounts of the other eight components were calculated according to the relative correction factors by the quantitative analysis of multi-components via a single marker method. Finally, the result of vector angle cosine analysis showed that there was no significant difference of the contents between the external standard method and the quantitative analysis of multi-components via a single marker method, indicating that the quantitative analysis of multi-components via a single marker method can be applied for the quality control of Rhizoma Paridis. As far as we know, this is also the first report to analyze nucleosides by the quantitative analysis of multi-components via a single marker method, providing an efficient and promising quality assessment method for other traditional Chinese medicine containing nucleosides.


Assuntos
Nucleosídeos/análise , Rizoma/química , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão
3.
Mikrochim Acta ; 187(1): 61, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31853650

RESUMO

An ultra-sensitive method is described here for the determination of HIF-1α (an early biomarker for myocardial infarction) in circulating exosomes in serum. Gold nanospheres were functionalized with a HIF-1α-binding aptamer via sulfydryl chemistry. The apt-AuNP-coated gold seeds were grown by seed-mediated growth, and this significantly increased the peroxidase-mimicking property the nanoparticles. A chromogenic system composed of 3,3'5,5'-tetramethylbenzidine and hydrogen peroxide was used. Absorbance at 652 nm increases linearly in the 0.3 to 200 ng L-1 HIF-1α concentration range, and the limit of detection is 0.2 ng L-1. The method was tested by analyzing rat serum from isoproterenol (ISO)-induced myocardial infarction. It allows HIF-1α to be directly determined in a 25 µL sample without preconcentration. The assay is not interfered by the polydispersity of exosomes released under either health and disease conditions. Graphical abstractGold nanospheres were functionalized with a HIF-1α-binding aptamer via sulfydryl chemistry. Nanosized gold seed particles were then modified with the functionalized gold nanospheres, and this strongly increases the peroxidase-mimicking activity of the nanomaterial. By using the tetramethylbenzidine/H2O2 chromogenic system, the absorbance at 652 nm increases linearly in the 0.3 to 200 ng L-1 HIF-1α concentration range.


Assuntos
Aptâmeros de Nucleotídeos/química , Colorimetria , Exossomos/química , Ouro/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/sangue , Peroxidase/química , Animais , Aptâmeros de Nucleotídeos/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Ensaio de Imunoadsorção Enzimática , Exossomos/metabolismo , Ouro/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Infarto do Miocárdio/sangue , Infarto do Miocárdio/metabolismo , Tamanho da Partícula , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície
4.
Molecules ; 24(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319475

RESUMO

We have developed a new competitive protein binding assay (CPBA) based on human serum albumin functionalized silicon dioxide nanoparticles (nano-SiO2-HSA) that can be used for naproxen determination in urine. Compared with a conventional multi-well reaction plate, nano-SiO2 with a high surface-area-to-volume ratio could be introduced as a stationary phase, markedly improving the analytical performance. Nano-SiO2-HSA and horseradish peroxidase-labeled-naproxen (HRP-naproxen) were prepared for the present CPBA method. In this study, a direct competitive binding to nano-SiO2-HSAwas performed between the free naproxen in the sample and HRP-naproxen. Thus, the catalytic color reactions were investigated on an HRP/3,3'5,5'-tetramethylbenzidine (TMB)/H2O2 system by the HRP-naproxen/nano-SiO2-HSA composite for quantitative measurement via an ultraviolet spectrophotometer. A series of validation experiments indicated that our proposed methods can be applied satisfactorily to the determination of naproxen in urine samples. As a proof of principle, the newly developed nano-CPBA method for the quantification of naproxen in urine can be expected to have the advantages of low costs, fast speed, high accuracy, and relatively simple instrument requirements. Our method could be capable of expanding the analytical applications of nanomaterials and of determining other small-molecule compounds from various biological samples.


Assuntos
Nanopartículas/química , Naproxeno/isolamento & purificação , Albumina Sérica Humana/genética , Dióxido de Silício/química , Peroxidase do Rábano Silvestre/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Nanoestruturas/química , Naproxeno/química , Ligação Proteica/genética , Albumina Sérica Humana/química
5.
Molecules ; 24(16)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434256

RESUMO

So far, there is no report on the quality evaluation of lemonade available in the market. In this study, a sample preparation method was developed for the determination of flavonoid glycosides by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) based on vortex-assisted dispersive liquid-liquid microextraction. First, potential flavonoids in lemonade were scanned and identified by ultra-performance liquid chromatography-time of flight mass spectrometry (UPLC-TOF/MS). Five flavonoid glycosides were identified as eriocitrin, narirutin, hesperidin, rutin, and diosmin according to the molecular formula provided by TOF/MS and subsequent confirmation of the authentic standard. Then, an ultra-performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QqQ/MS) method was developed to determine these five flavonoid glycosides in lemonade. The results showed that the content of rutin in some lemonade was unreasonably high. We suspected that many illegal manufacturers achieved the goal of low-cost counterfeiting lemonade by adding rutin. This suggested that it was necessary for relevant departments of the state to make stricter regulations on the quality standards of lemonade beverages.


Assuntos
Bebidas/análise , Cromatografia Líquida/métodos , Citrus/química , Flavonoides/análise , Análise de Alimentos/métodos , Glicosídeos/análise , Espectrometria de Massas/métodos , Contaminação de Alimentos/análise , Microextração em Fase Líquida
6.
Molecules ; 24(1)2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30583462

RESUMO

So far, there has been no quality evaluation of Tricholoma matsutake. Nucleic acid compounds are a kind of functional ingredient in T. matsutake that is beneficial to human health. In this study, a UPLC-TOF/MS method was first used to scan and identify the potential nucleic acid compounds in T. matsutake. Based on the calculation of the molecular formula and subsequent confirmation by authentic standards, 15 nucleic acid compounds were unambiguously identified: adenosine, cytidine, guanosine, inosine, thymidine, uridine, xanthosine dehydrate, 2'-deoxyadenosine, 2'-deoxycytidine, 2'-deoxyguanosine, 2'-deoxyuridine, adenosine 5'-monophosphate, cytidine 5'-monophosphate, guanosine 5'-monophosphate, and uridine 5'-monophosphate. Then, a UPLC-QqQ/MS method was developed for the subsequent quantitative analysis. After validating the limits of quantification, detection, precision, repeatability, and recovery through a calibration curve, the content of 15 nucleic acid compounds was determined by the proposed UPLC-QqQ/MS method in 80 T. matsutake samples collected from different regions in Sichuan province, Southwest China. After the statistical analysis, we suggest that the total content of nucleic acid compounds in the qualified T. matsutake should be higher than 24.49 mg/100 g. The results indicated that the combined use of UPLC-TOF/MS and UPLC-QqQ/MS is efficient for fast identification and determination of nucleic acid compounds to comprehensively evaluate the quality of T. matsutake.


Assuntos
Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Qualidade dos Alimentos , Ácidos Nucleicos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tricholoma/química , Análise de Alimentos/métodos , Estrutura Molecular , Ácidos Nucleicos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Molecules ; 23(11)2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30423914

RESUMO

In the present study, 11 non-anthocyanin polyphenols, gallic acid, protocatechuate, vanillic acid, syringic acid, ferulic acid, quercetin, catechin, epicatechin, epigallocatechin gallate, gallocatechin gallate and epicatechin gallate-were firstly screened and identified from blueberries using an ultra performance liquid chromatography⁻time of flight mass spectrography (UPLC-TOF/MS) method. Then, a sample preparation method was developed based on vortex-assisted dispersive liquid-liquid microextraction. The microextraction conditions, including the amount of ethyl acetate, the amount of acetonitrile and the solution pH, were optimized through the multi-objective response surface methodology and desirability function approach. Finally, an ultra performance liquid chromatography⁻triple quadrupole mass spectrography (UPLC-QqQ/MS) method was developed to determine the 11 non-anthocyanin polyphenols in 25 commercial blueberry samples from Sichuan province and Chongqing city. The results show that this new method with high accuracy, good precision and simple operation characteristics, can be used to determine non-anthocyanin polyphenols in blueberries and is expected to be used in the analysis of other fruits and vegetables.


Assuntos
Mirtilos Azuis (Planta)/química , Microextração em Fase Líquida , Polifenóis/química , Polifenóis/isolamento & purificação , Análise de Variância , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
Anal Bioanal Chem ; 409(19): 4607-4614, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28573321

RESUMO

A simple, fast, and highly sensitive direct competitive enzyme-linked immunosorbent assay (ELISA) based on bovine serum albumin (BSA) antigen labeled amine-terminated silicon dioxide (SiO2-NH-BSA) nanoparticles was developed to determine residual BSA in vaccines. As nano-ELISA using nanomaterials with a very high surface-to-volume ratio has emerged as a promising strategy, SiO2-NH-BSA nanoparticles were prepared in this study by the coupling of BSA to SiO2 nanoparticles modified with amidogen, followed by the quantification of BSA via a direct competitive binding of BSA-antigen-labeled SiO2 nanoparticles to anti-BSA antibody conjugated with horseradish peroxidase. The validation study showed that the linear range of this method was from 1 to 90 ng/mL (r = 0.998) and the limit of detection was 0.67 ng/mL. The intra-assay and interassay coefficients of variation were less than 10% at three concentrations (10, 40, and 70 ng/mL), and the recovery was 92.4%, indicating good specificity. As a proof of principle, this new method was applied in the analysis of residual BSA in five different vaccines. Bland-Altman plots revealed that there was no significant difference in the accuracy and precision between our new method and the most commonly used sandwich ELISA. From the results taken together, the new method developed in this study is more sensitive and facile with lower cost and thus demonstrated potential to be applied in the quality control of biological products. Graphical Abstract Illustration of the procedures of the direct competitive enzyme immunoassay.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Nanotecnologia , Soroalbumina Bovina/análise , Vacinas/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Reprodutibilidade dos Testes , Dióxido de Silício/química
9.
Molecules ; 22(8)2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28758976

RESUMO

There is an urgent need for a water-soluble derivative of astragaloside IV for drug R&D. In the present study, a remarkably simple method for the preparation of such a water-soluble derivative of astragaloside IV has been developed. This protocol involves oxidative 2,2,6,6-tetramethylpiperidine-1-oxyl free radical (TEMPO)-mediated transformation of astragaloside IV to its carboxylic acid derivative, which is a new compound named astragalosidic acid. The structure of astragalosidic acid was elucidated by means of spectroscopic analysis. Its cardioprotective activity was investigated using an in vitro model of cardiomyocyte damage induced by hypoxia/reoxygenation in H9c2 cells. The oxidative TEMPO-mediated transformation proposed in the present study could be applied to other natural saponins, offering an effective and convenient way to develop a new compound with greatly improved structure-based druggability.


Assuntos
Óxidos N-Cíclicos/química , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/metabolismo , Saponinas , Triterpenos , Animais , Linhagem Celular , Camundongos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Oxirredução , Saponinas/química , Saponinas/farmacologia , Triterpenos/química , Triterpenos/farmacologia
10.
J Sep Sci ; 37(6): 704-10, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24453172

RESUMO

A new extraction agent featuring dopamine self-polymerized on magnetic Fe3 O4 nanoparticles has been successfully synthesized and evaluated for the SPE of berberine from the extract of the traditional Chinese medicinal plant, Cortex Phellodendri. The nanoparticles prepared possessed a core-shell structure and showed super-paramagnetism. It was found that these polydopamine-coated nanoparticles exhibited strong and selective adsorption for berberine. Among the chemical components present in C. Phellodendri, only berberine was adsorbed by the nanoparticles and extracted by a following SPE procedure. Various conditions such as the amount of polydopamine-coated nanoparticles, desorption solvent, desorption time and equilibrium time were optimized for the SPE of berberine. The purity of berberine extracted from C. Phellodendri was determined to be as high as 91.3% compared with that of 9.5% in the extract. The established SPE protocol combined advantages of highly selective enrichment with easy magnetic separation, and proved to be a facile efficient procedure for the isolation of berberine. Further, the prepared polydopamine-coated magnetic nanoparticles could be reused for multiple times, reducing operational cost. The applicability and reliability of the developed SPE method were demonstrated by isolating berberine from three different C. Phellodendri extracts. Recoveries of 85.4-111.2% were obtained with relative standard deviations ranging from 0.27-2.05%.


Assuntos
Berberina/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Indóis/química , Nanopartículas de Magnetita/química , Polímeros/química , Berberina/química , Cromatografia Líquida de Alta Pressão , Modelos Moleculares , Estrutura Molecular
11.
J Pharm Anal ; 14(3): 295-307, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618252

RESUMO

Triterpenoids widely exist in nature, displaying a variety of pharmacological activities. Determining triterpenoids in different matrices, especially in biological samples holds great significance. High-performance liquid chromatography (HPLC) has become the predominant method for triterpenoids analysis due to its exceptional analytical performance. However, due to the structural similarities among botanical samples, achieving effective separation of each triterpenoid proves challenging, necessitating significant improvements in analytical methods. Additionally, triterpenoids are characterized by a lack of ultraviolet (UV) absorption groups and chromophores, along with low ionization efficiency in mass spectrometry. Consequently, routine HPLC analysis suffers from poor sensitivity. Chemical derivatization emerges as an indispensable technique in HPLC analysis to enhance its performance. Considering the structural characteristics of triterpenoids, various derivatization reagents such as acid chlorides, rhodamines, isocyanates, sulfonic esters, and amines have been employed for the derivatization analysis of triterpenoids. This review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of triterpenoids. Moreover, the limitations and challenges encountered in previous studies are discussed, and future research directions are proposed to develop more effective derivatization methods.

12.
ACS Pharmacol Transl Sci ; 7(2): 421-431, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38357273

RESUMO

In traditional Chinese medicine, Radix Astragali has played a vital role in treating progressive fibrotic diseases. One of its main active components, astragaloside IV, is a promising anti-fibrotic treatment despite its extremely low bioavailability. Our study aimed to optimize sodium astragalosidate (SA) by salt formation to improve solubility and oral absorption for anti-fibrotic therapy in vivo. Isoproterenol-induced myocardial fibrosis rat models and obese BKS-db mice presenting diabetic kidney fibrosis were used in this study. Daily oral administration of SA (20 mg/kg) for 14 days ameliorated cardiac fibrosis by reducing collagen accumulation and fibrosis-related inflammatory signals, including TNF-α, IL-1ß, and IL-6. In db/db mice, SA (5,10, and 20 mg/kg per day for 8 weeks) dose-dependently alleviated lipid metabolism impairment and renal dysfunction when administered orally. Furthermore, Western blot and immunohistochemistry analyses demonstrated that SA treatment inhibited renal fibrosis by suppressing TGF-ß1/Smads signaling. Taken together, our findings provide the oral-route medication availability of SA, which thus might offer a novel lead compound in preclinical trial-enabling studies for developing a long-term therapy to treat and prevent fibrosis.

13.
Anal Bioanal Chem ; 405(27): 8807-17, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24048516

RESUMO

Although metabolic study of individual active compounds isolated from herbal plants has been intensive, it cannot truly reflect the fate of herbs because the herbal extracts in use have many constituents. To address this problem, whole extracts of herbs should be investigated. Microsomes have been heavily used in the in vitro metabolic study of drugs, and various materials have been used to immobilize microsomes to develop highly effective and reusable bioreactors in this field. In this work, rat liver microsomes were immobilized on magnetic nanoparticles (LMMNPs) to develop a highly active and recoverable nanoparticle bioreactor. Using this bioreactor, we investigated the in vitro metabolism of Rhizoma coptidis extract. Incubation of berberine, a major active ingredient of R. coptidis, with LMMNPs for 20 min produced two metabolites, i.e., demethyleneberberine and thalifendine, at high levels. From a comparison of the time courses of thalifendine formation obtained by ultraperformance liquid chromatography-mass spectrometry analysis, it was found that LMMNPs had a higher biological activity than free liver microsomes in metabolizing berberine. Further, the activity of LMMNPs remained almost unchanged after six consecutive uses in the incubation tests. Metabolism of R. coptidis extracts by LMMNPs was studied. The same two metabolites of berberine, i.e., demethyleneberberine and thalifendine, were detected. After a thorough study seeking support for this observation, it was found that demethyleneberberine was the common metabolite of five protoberberine-type alkaloids present in R. coptidis extract, including palmatine, jatrorrhizine, columbanine, epiberberine, and berberine.


Assuntos
Alcaloides de Berberina/metabolismo , Medicamentos de Ervas Chinesas/metabolismo , Nanopartículas de Magnetita/química , Microssomos Hepáticos/metabolismo , Animais , Berberina/análogos & derivados , Berberina/metabolismo , Reatores Biológicos , Biotransformação , Cromatografia Líquida de Alta Pressão , Coptis chinensis , Medicamentos de Ervas Chinesas/química , Reutilização de Equipamento , Cinética , Masculino , Microssomos Hepáticos/química , Ratos , Ratos Sprague-Dawley
14.
Zhongguo Zhong Yao Za Zhi ; 38(21): 3713-9, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24494560

RESUMO

To establish an HPLC digital fingerprint for Rhizoma Coptidis produced in E'mei, and apply it in the determination of Rhizoma Coptidis herbs produced in main producing areas nationwide, while determining the content of seven quaternary ammonium alkaloids contained in Coptidis Rhizoma, in order to provide basis for scientific evaluation and effective control over quality of Rhizoma Coptidis. Diamonsil C18 column (4.6 mm x 250 mm, 5 microm) was adopted and eluted with acetonitrile 0.025 mol x L(-1) KH2PO4 solution (adjust pH to 3.0 with H3PO4) (40:60) containing SDS 1.7 g x L(-1). The flow rate was 1.2 mL x min(-1), the detective wavelength was 345 nm, and the column temperature was 40 degrees C. The chromatographic fingerprint similarity evaluation system for traditional Chinese medicines (state pharmacopeia committee of China) was used for analysis. The chromatographic fingerprint similarity of ten batches of Coptidis Rhizoma samples produced in Emei was more than 0. 99. There were altogether 10 common peaks, and eight of them were identified. A comparative analysis showed a high similarity between samples from five main producing areas nationwide and Coptidis Rhizoma herbs in E'mei. Meanwhile, the content of seven major alkaloids contained in Coptidis Rhizoma herbs, namely groenlandicine, columbamine, jatrorrhizine, epiberberine, coptisine, palmatine and berberine were determined. As the method was highly sensitive and specific, the combination of HPLC digital fingerprint and alkaloid content determination could reflect its inherent quality in an all-round way, which provided scientific basis for the quality control of Coptidis Rhizoma.


Assuntos
Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Ranunculaceae/química , Coptis chinensis , Rizoma/química
15.
J Pharm Biomed Anal ; 231: 115414, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37141677

RESUMO

Radix Astragali (RA) is commonly used in Asian herbal therapy or food supply, and astragalosides and flavonoids are its major components with diverse pharmaceutical effects. To provide new information on the potential cardiovascular benefits of RA administered orally, the bioaccessibility of these compounds with relevant in vitro digestion parameters was determined for four digestion phases (oral, gastric, small and large intestines) by ultrahigh-performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UPLC-Q-TOF/MS). Meanwhile, we compared the effects of digestion products on advanced glycation end products (AGEs)-induced intracellular reactive oxygen species (ROS) levels in a human arterial endothelial cells (HAECs) model, and studied the potential of RA against oxidative stress-related cardiovascular disease. The changes of saponins and flavonoids composition and antioxidant activity after digestion in intestines were mainly due to the astragaloside IV (AS-IV) biosynthesis involving saponins acetyl isomerization and deacetylation, and the flavonoid glycosides converted to aglycone by deglycosylation processes. All these results suggest that acetyl biotransformation of RA in small intestine directly influenced the response to oxidative stress, and might provide a reference for elucidation of the multi-component action after oral RA in cardiovascular health care.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Células Endoteliais/química , Saponinas/química , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Biotransformação , Digestão
16.
Front Pharmacol ; 13: 987882, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36210826

RESUMO

LS-102 is a new derivative of astragaloside IV (AGS IV) that has been shown to possess potentially significant cardioprotective effects. However, there are no reports concerning its interaction with human serum albumin (HSA) and toxicology in vertebrates. The present investigation was undertaken to characterize the interaction of AGS IV and LS-102 with HSA using equilibrium dialysis and UHPLC-MS/MS methods, along with computational methods. Notably, the effects of AGS IV and LS-102 were studied in vivo using the zebrafish embryo model. Markers related to embryonic cardiotoxicity and thrombosis were evaluated. We showed that the plasma protein binding rate of AGS IV (94.04%-97.42%) was significantly higher than that of LS-102 (66.90%-69.35%). Through site marker competitive experiments and molecular docking, we found that AGS IV and LS-102 were located at the interface of subdomains IIA and IIIA, but the site I might be the primary binding site. Molecular dynamics revealed that AGS IV showed a higher binding free energy mainly due to the stronger hydrophobic and hydrogen bonding interactions. Moreover, the secondary structure implied no obvious effect on the protein structure and conformation during the binding of LS-102. LS-102 significantly ameliorated the astramizole-induced heart rate slowing, increased SV-BA spacing, and prevented arachidonic acid-induced thrombosis in zebrafish. To our knowledge, we are the first to reveal that LS-102 binds to HSA with reversible and moderate affinity, indicating its easy diffusion from the circulatory system to the target tissue, thereby providing significant insights into its pharmacokinetic and pharmacodynamic properties when spread in the human body. Our results also provide a reference for the rational clinical application of LS-102 in the cardiovascular field.

17.
Anal Bioanal Chem ; 399(3): 1223-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21088827

RESUMO

The chemical composition of herbal medicines is very complex, and their therapeutic effects are determined by multi-components with sophisticated synergistic and/or suppressive actions. Therefore, quality control of herbal medicines has been a formidable challenge. In this work, we describe a fast analytical method that can be used for quality assessment of herbal medicines. The method is based on ligand fishing using human-serum-albumin-functionalized magnetic nanoparticles (HSA-MNPs) and mass spectrometry. To demonstrate the applicability of the proposed method, eight samples of Dioscorea panthaica were analyzed. The sampled plants were of both wild and cultivated origins. They grew at different geographical locations and were harvested at different times. The ligands bound to HSA-MNPs were isolated from the plant extracts and detected by using direct infusion electrospray ionization mass spectrometry (DI-ESI-MS). Chemical identity has been confirmed for five of the ligands isolated. From more than 15 peaks in the ESI-MS spectrum, 11 common peaks were selected for calculating the correlation coefficient and cosine ratio. The values of correlation coefficient and cosine ratio were >0.9824 and >0.9988, respectively, for all the samples tested. The results indicated a high level of similarity among the eight D. panthaica samples. Compared with chromatographic fingerprint analysis, the proposed HSA-MNP-based DI-ESI-MS/MS approach was not only fast and easy to carry out but also biological-activity-oriented, promising a more effective data interpretation and thus reliable assessment conclusions.


Assuntos
Dioscorea/química , Medicamentos de Ervas Chinesas/análise , Nanopartículas de Magnetita/química , Extratos Vegetais/análise , Albumina Sérica/química , Humanos , Ligantes , Conformação Molecular , Controle de Qualidade , Espectrometria de Massas por Ionização por Electrospray , Estereoisomerismo
18.
J Sep Sci ; 34(22): 3240-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22052824

RESUMO

An extraction agent featuring a natural product, baicalin, anchored on the surface of nanomagnetic particles (BMNPs) is herein reported. A facile solid-phase extraction (SPE) procedure with high selectivity toward flavonoids using BMNPs has been established. BMNPs were proven very effective for enriching flavonoids from extracts of medicinal plants such as Rosa chinensis. The SPE protocol involving a convenient solid-liquid separation by using an external magnet field was easy to carry out. Further, the SPE sorbent (BMNPs) could be reused for many times reducing the operation cost. Importantly, flavonoids retained on the BMNPs were effectively recovered by eluting with methanol. Coupling the proposed SPE with ESI-MS/MS allowed a quick quantification of flavonoids in herbal extracts. Simultaneous determination of eight flavonoids extracted from R. chinensis was demonstrated in this work.


Assuntos
Flavonoides/isolamento & purificação , Nanopartículas de Magnetita/química , Extratos Vegetais/isolamento & purificação , Rosa/química , Extração em Fase Sólida/métodos , Adsorção , Flavonoides/química , Extratos Vegetais/química , Extração em Fase Sólida/instrumentação
19.
Rapid Commun Mass Spectrom ; 24(22): 3335-9, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-20973009

RESUMO

The chemical diversity of secondary metabolites in medicinal plant makes it a huge challenge to isolate the bioactive compounds from herbal extracts, so quick recognition of the bioactive ones is of vital importance for improving the efficiency of isolation. In this study, a ligand fishing experiment based on human serum albumin functionalized magnetic nano-particles (HSA-MNPs) was performed to probe the bioactive components in a traditional Chinese medicinal plant, Dioscorea panthaica. The minor compounds fished out by HSA-MNPs were identified by electrospray ionization mass spectrometry (ESI-MS), and then separated from the extract of the whole plant by one or two steps of column chromatography under the guidance of ESI-MS. Four biologically active compounds, progenin II, progenin III, dioscin and gracillin, were isolated much faster than in the normal lengthy phytochemical procedure. The present study demonstrates that biological macromolecule (protein, enzyme, receptor, et al.) functionalized MNPs may serve as baits to recognize bioactive small molecules in complex herbal extracts. It is expected that a macromolecule functionalized MNPs-based ligand fishing experiment coupled with ESI-MS may accelerate the process of identification and isolation of bioactive components from medicinal plants, and thus benefit the speed of drug discovery.


Assuntos
Dioscorea/química , Medicamentos de Ervas Chinesas/química , Nanopartículas de Magnetita/química , Albumina Sérica/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espirostanos/química , Medicamentos de Ervas Chinesas/metabolismo , Humanos , Técnicas de Sonda Molecular , Sondas Moleculares/química
20.
Front Pharmacol ; 11: 1083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33041784

RESUMO

Our previous studies showed that Astragaloside IV derivative (LS-102) exhibited potent protective function against ischemia reperfusion (I/R) injury, but little is known about the mechanisms. Mitochondrial fission regulated by dynamin-related protein1 (Drp1) is a newly recognized determinant of mitochondrial function. This study aimed to investigate the protection of LS-102 on mitochondrial structure and function by regulating the activity of Drp1 using models of H9c2 cardiomyocyte injury induced by hypoxia-reperfusion (H/R), and rat heart injury induced by I/R. The results showed that LS-102 significantly decreased apoptosis, levels of ROS, CK, LDH, and calcium, upregulating MMP, and the Bax/Bcl-2 ratio in cardiomyocytes during I/R injury. Furthermore, LS-102 prevented I/R-induced mitochondrial fission by decreasing Drp1's mitochondrial localization through decreasing the phosphorylation of Drp1 at Ser616 (Drp1Ser616) and increasing the phosphorylation of Drp1 at Ser637 (Drp1Ser637) in H9c2 cells. Importantly, we also robustly confirmed Drp1Ser616 as a novel GSK-3ß phosphorylation site. GSK-3ß-mediated phosphorylation at Drp1Ser616 may be associated with mitochondrial fission during I/R of cardiomyocytes. In conclusion, LS-102 exerts cardio protection against I/R-induced injury by inhibiting mitochondrial fission via blocking GSK-3ß-mediated phosphorylation at Ser616 of Drp1.

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