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1.
J Am Chem Soc ; 146(4): 2798-2804, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38145451

RESUMO

The combination of the chiral concept and inorganic nanostructures holds great potential for significantly impacting catalytic processes and products. However, the synthesis of inorganic nanomaterials with engineered chiroptical activity and identical structure and size presents a substantial challenge, impeding exploration of the relationship between chirality (optical activity) and catalytic efficiency. Here, we present a facile wet-chemical synthesis for achieving intrinsic and tunable chiroptical activity within colloidal copper oxide nanostructures. These nanostructures exhibit strong spin-polarization selectivity compared with their achiral counterparts. More importantly, the ability to engineer chiroptical activity within the same type of chiral nanostructures allows for the manipulation of spin-dependent catalysis, facilitating a study of the connection between the chiroptical magnitude (asymmetric factor) and catalytic performance in inorganic nanostructures. Specifically, using these materials as model catalysts in a proof-of-concept catalytic reaction, we reveal a linear correlation between the asymmetric factor of chiral nanomaterials and the efficiency of the catalytic reaction. This work paves the way for the development of chiral inorganic nanosystems and their application in catalysis through chiroptical engineering.

2.
Rapid Commun Mass Spectrom ; 38(20): e9893, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39185578

RESUMO

RATIONALE: Anemarrhenae Rhizoma (AR) has been a frequently utilized traditional Chinese medicine (TCM) for an extended period, with its salt-processed variant being a prevalent application form. Contemporary pharmacological investigations have demonstrated that the salt-processed iteration exhibits a multitude of markedly augmented pharmacological properties. However, whether the pharmacodynamic material basis of this change is related to volatile substances remains unclear. The aim of this study was to develop a strategy to screen volatile pharmacodynamic substances in AR and salt-processed AR (SAR). METHODS: A comprehensive approach was developed to identify volatile pharmacodynamic compounds by integrating plant metabolomics, target network pharmacology, and molecular docking technology. Plant metabolomics using GC-MS analysis was conducted to identify volatile chemical markers distinguishing between AR and SAR. Subsequently, network pharmacology was utilized to investigate the correlation between chemical markers and associated diseases. Following this, molecular docking technology was utilized to explore the correlation between chemical markers and disease targets, resulting in the discovery of potential quality control markers. RESULTS: Fifty volatile compounds were isolated and identified in the salt of AR and SAR. The findings from plant metabolomics analysis demonstrated a distinct differentiation, revealing 13 volatile chemical markers that distinguish between AR and SAR. A target (PPARG) associated with diabetes was identified through target network pharmacology analysis. Thirteen volatile components were subsequently chosen as potential quality markers, taking into account their hypoglycemic activity. CONCLUSIONS: The method developed provides a novel strategy for the identification of pharmacophores in AR and SAR, as well as establishing a foundation for the exploration of the volatile differential components and pharmacodynamics in various processed products of TCMs. Additionally, the findings of this study can serve as a theoretical framework for the development and utilization of volatile components in AR and its processed derivatives.


Assuntos
Anemarrhena , Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Simulação de Acoplamento Molecular , Rizoma , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Rizoma/química , Anemarrhena/química , Farmacologia em Rede
3.
Nano Lett ; 23(10): 4384-4389, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37162145

RESUMO

Circularly polarized luminescence (CPL) is well-studied in molecular systems but has been rarely reported in pure inorganic nanoscale crystals. Herein, we develop a family of pure inorganic rare-earth nanowires with robust and color-tunable CPL emissions. The chiral rare earth nanowires possess intrinsic atomic chirality with controlled handedness that is guided by the enantiomers with molecular chirality in the synthesis. By varying luminescent ions incorporated in the crystal lattice, color-tunable CPL can be achieved and is thermally robust, preserving emission over 300 °C, distinct from existing CPL-active materials. Moreover, as a proof of concept, we demonstrate that the synthesized nanostructures can be easily dispersed in a polymer matrix to enable transparent and flexible CPL films. This study opens up a promising avenue to design robust and tunable CPL materials helpful to the understanding of inorganic chiral information and capable of further applications in novel optoelectronic devices.

4.
Rapid Commun Mass Spectrom ; 37(7): e9473, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36645740

RESUMO

RATIONALE: Anemarrhenae Rhizoma (AR) has been an often used traditional Chinese medicine (TCM) for a long time. Its salt-processed form is one of the most common application forms. Modern pharmacological research has shown that the salt-processed product has various significantly enhanced pharmacological activities. However, the pharmacodynamic material basis of this change is not yet known. The aim of this study was to develop a strategy to screen pharmacodynamic substances in AR and salt-processed AR (SAR). METHODS: An integrated strategy combining plant metabolomics with molecular docking technology was established to screen pharmacodynamic substances. The plant metabolomics analysis was performed to select the chemical markers between AR and SAR. Then, molecular docking technology was applied to explore the relationship between chemical markers and diabetes targets (α-glucosidase). Finally, potential quality control markers were screened. RESULTS: There were significant differences in the quantification of nine steroidal saponins between AR and SAR. The results of plant metabolomics analysis showed a quite clear discrimination including 29 chemical markers between AR and SAR. Taking the hypoglycemic activity into consideration, 16 steroidal saponins were selected as potential quality markers. CONCLUSIONS: The developed method not only supplied an optional solution to search for pharmacophores in AR and SAR, but also provided a foundation for the study of the differential components and pharmacodynamics in various processed products of TCMs.


Assuntos
Anemarrhena , Medicamentos de Ervas Chinesas , Saponinas , Medicamentos de Ervas Chinesas/química , Simulação de Acoplamento Molecular , Anemarrhena/química , Controle de Qualidade , Saponinas/análise , Metabolômica
5.
Rapid Commun Mass Spectrom ; 37(1): e9403, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36184262

RESUMO

RATIONALE: Fritillaria cirrhosae bulbus (BFC), a typical traditional Chinese medicine with multiple botanical sources, has been used for relieving cough and reducing sputum. Studies have shown that there were obvious differences in the chemical compositions and clinical efficacy of different sources of BFC. How to characterise BFC from botanical sources accurately and quickly is vital for drug quality evaluation and clinical applications. METHODS: In the present study, an integrated strategy of plant metabolomics combined with the target network pharmacology was developed to characterise BFC. Plant metabolomics analysis was performed to screen out the chemical markers of six species of BFC. Then, target network pharmacology was applied to explore the relationship between chemical markers and related diseases. Finally, potential Q-markers for species characterization were selected by combined analysis of plant metabolomics and the target network pharmacology. RESULTS: A total of 67 Fritillaria alkaloid compounds were identified. Six species showed clear characterization by multivariate statistical analysis, resulting in 12 chemical markers. Meanwhile, a total of nine components related to asthma were screened out based on the target network pharmacology. Taking content difference and pharmacological activity into consideration, nine constituents were selected as potential Q-markers. CONCLUSION: The method developed provided not only a standard protocol for characterising different species of BFC directly, but also an effective approach for multisource medicines discrimination.


Assuntos
Medicamentos de Ervas Chinesas , Fritillaria , Medicamentos de Ervas Chinesas/química , Farmacologia em Rede , Fritillaria/química , Medicina Tradicional Chinesa , Metabolômica
6.
Biomed Chromatogr ; 37(9): e5682, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37158044

RESUMO

Isodon excisoides (Y.Z.Sun ex C.H.Hu) H. Hara has been often used to treat liver diseases in folk medicine. However, the potential hepatoprotective mechanism of I. excisoides remains unclear. In this study, the mechanism of I. excisoides in alleviating drug-induced liver injury (DILI) was explored using a strategy combining metabolomics with network pharmacology for the first time. First, serum metabolomics was applied to identify differential metabolites and enrich metabolic pathways. The potential targets of I. excisoides for the treatment of DILI were investigated by network pharmacology. Subsequently, a comprehensive network of network pharmacology and metabolomics was established to find the key genes. Finally, molecular docking technology was used to further verify the key targets. As a result, four key genes including TYMS, IMPDH2, DHODH, and ASAH1 were identified. The proteins produced by these genes had high affinity with the corresponding diterpenoids. These results indicate that the components of I. excisoides play a liver-protective role by affecting the aforesaid key genes and key proteins. Our results offer a novel strategy for determining the pharmacological effects and potential targets of natural compounds.

7.
Mol Biol Rep ; 49(8): 7337-7345, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35585377

RESUMO

BACKGROUND: The mechanism by which MSC-CM protects neuronal cells against ischemic injury remains to be elucidated. In this study, we aimed to clarify the protective effect of umbilical cord-derived mesenchymal stem cell conditioned medium (UC-MSC-CM) on neuronal oxidative injury and its potential mechanism. METHODS AND RESULTS: Neuronal oxidative damage was mimicked by H2O2 treatment of the HT22 cell line. The numbers of cleaved-Caspase-3-positive cells and protein expression of Caspase-9 induced by H2O2 treatment were decreased by UC-MSC-CM treatment. Furthermore, SOD protein expression was increased in the MSC-CM group compared with that in the H2O2 group. The H2O2-induced TRPM2-like currents in HT22 cells were attenuated by MSC-CM treatment. In addition, H2O2 treatment downregulated the expression of p-JNK protein in HT22 cells, and this the downward trend was reversed by incubation with MSC-CM. CONCLUSIONS: UC-MSC-CM protects neurons against oxidative injury, possibly by inhibiting activation of TRPM2 and the JNK signaling pathway.


Assuntos
Células-Tronco Mesenquimais , Canais de Cátion TRPM , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Sistema de Sinalização das MAP Quinases , Células-Tronco Mesenquimais/metabolismo , Neurônios/metabolismo , Estresse Oxidativo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Cordão Umbilical
8.
J Sep Sci ; 45(15): 2819-2832, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35638750

RESUMO

Peimine, one of the major quality markers in Fritillaria Cirrhosae Bulbus, was expected to become a new anti-asthma drug. However, its metabolic profiles and anti-asthma mechanism have not been clarified previously. In this study, a method was developed for the detection of peimine metabolites in vitro by ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry. The potential anti-asthma mechanism was predicted by an integrated analysis of network pharmacology and molecular docking. A total of 19 metabolites were identified with the aid of software and molecular networking. The metabolic profiles of peimine elucidated that the metabolism was a multi-pathway process with characteristics of species difference. The network pharmacology results showed that peimine and its metabolites could regulate multiple asthma-related targets. The above targets were involved in various regulatory pathways linked to asthma. Moreover, the results of molecular docking showed that both peimine and its metabolites had a certain affinity with the ß2 adrenergic receptor. The results provided not only important references to understand the metabolism and pharmacodynamic changes of peimine in vitro, but also supporting data for further pharmacological evaluation. It also provided a new perspective for clarifying the functional changes of traditional Chinese medicine in vitro.


Assuntos
Antiasmáticos , Cevanas , Medicamentos de Ervas Chinesas , Antiasmáticos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Simulação de Acoplamento Molecular , Farmacologia em Rede
9.
Biomed Chromatogr ; 36(8): e5409, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35562325

RESUMO

A specific ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) method has been described for the simultaneous determination of the metabolites of tacrine, bupropion, diclofenac, dextromethorphan and midazolam, which are the five probe drugs of the five cytochrome P450 (CYP450) isoforms CYP1A2, CYP2B, CYP2C11, CYP2D1 and CYP3A4. The inhibition degree was determined by calculating the IC50 . The chromatographic separation was performed on a C18 column with a mobile phase consisting of 0.1% formic acid and acetonitrile. The mass spectrometric analysis was conducted in positive electrospray ionization mode. The IC50 values of CYP1A2, CYP2B, CYP2C11, CYP2D1 and CYP3A were 113.4, 83.78, 22.50, 9.081 and 52.76 µmol L-1 , respectively. The in vitro results demonstrated that vindoline could inhibit CYP2D1 activity in rats, and weak inhibitory effect on CYP2C11 and CYP3A, but had no obvious effects on CYP1A2 and CYP2B.


Assuntos
Citocromo P-450 CYP1A2 , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Isoformas de Proteínas , Ratos , Espectrometria de Massas em Tandem/métodos , Vimblastina/análogos & derivados
10.
Biomed Chromatogr ; 36(10): e5439, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35778888

RESUMO

To evaluate the effect of imrecoxib on CYP2C11 enzyme activity, mRNA, and protein expression, a UPLC method was established. Tolbutamide was selected as the CYP2C11 enzyme-specific probe drug and incubated with imrecoxib in rat liver microsomes. The yield of 4-hydroxytolbutamide was measured using UPLC to investigate the effect of imrecoxib on CYP2C11 enzyme activity. Imrecoxib (10 mg/kg) was administered intragastrically twice daily. After 1, 7, and 14 days of administration, the liver tissues were analyzed. The expression of CYP2C11 enzyme mRNA was determined using reverse transcription-polymerase chain reaction, and its protein expression was determined using Western blot analysis. Imrecoxib concentration was inversely proportional to the production of 4-hydroxytolbutamide in liver microsomes. Imrecoxib demonstrated a dose-dependent inhibitory effect on CYP2C11 activity with IC50 = 74.77 µM. After administration, reverse transcription-polymerase chain reaction showed CYP2C11 enzyme mRNA expressions were 65% (P < 0.05), 35%, and 34% of the control group, respectively (P < 0.01). Western blot analysis showed CYP2C11 enzyme protein expressions were 80, 37, and 34% of the control group, respectively (P < 0.01). Imrecoxib can reduce mRNA and protein expression of CYP2C11 enzyme in rat liver and inhibit the activity of CYP2C11 enzyme in a dose-dependent manner. However, it does not produce clinically significant drug interactions.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Pirróis , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Família 2 do Citocromo P450/genética , Família 2 do Citocromo P450/metabolismo , Microssomos Hepáticos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/farmacologia , Ratos , Esteroide 16-alfa-Hidroxilase/genética , Esteroide 16-alfa-Hidroxilase/metabolismo , Sulfetos
11.
Chem Biodivers ; 19(12): e202200748, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36369642

RESUMO

Tyrosinase inhibitors can alleviate the harm to the liver caused by tyrosinase. How to effectively screen out natural tyrosinase inhibitors becomes a focus. In this study, Isodon excisoides was first extracted with the ultrasound optimized by response surface methodology. Then, a method combined ultrafiltration with ultra-liquid chromatography mass spectrometry (UHPLC/MS) was built to screen and identify tyrosinase inhibitors. The binding energies of active ingredients to tyrosinase were calculated by molecular docking. The reliability of the results was validated by the IC50 of enzyme inhibition assay. As a result, the binding energies of 7 components including excisanin B, lasiokaurin, rabdophyllin G, rabdoserrin B, rabdosin D, rabdosinate and weisiensin were lower than that of resveratrol. It was indicated that these components had high tyrosinase inhibitory activity. The IC50 values of lasiokaurin and excisanin B were 177 and 142 µmol/mL, which were less than that of resveratrol (183 µmol/mL). It showed that this way was simple, rapid, reliable and effective, which provided a new strategy to screen natural bioactive compounds from plants.


Assuntos
Isodon , Monofenol Mono-Oxigenase , Simulação de Acoplamento Molecular , Cromatografia Líquida de Alta Pressão/métodos , Isodon/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Resveratrol , Ultrafiltração/métodos , Reprodutibilidade dos Testes
12.
Phytochem Anal ; 33(4): 517-532, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35144310

RESUMO

INTRODUCTION: The diterpenoids are the most important active constituents that contribute to the pharmacological efficacy of Isodon serra (Maxim.) Hara. Clinical studies have revealed that diterpenoids possess multiple features, e.g. antitumour, antitubercular and anti-ischemic activities. Therefore, the identification and detection of diterpenoids may be equally important for understanding the pharmacological basis of diterpenoids and enhancing the product quality control of I. serra. OBJECTIVES: The purpose of this study was to develop a practical analysis approach of rapid characterisation using ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) for the structure characterisation of the ent-kaurane diterpenoids from I. serra. METHODOLOGY: The analytical strategy was as follows: first, ent-kaurane diterpenoids were detected by a novel on-line data acquisition approach, i.e. sequential window acquisition of all theoretical fragment-ion spectra (SWATH). Second, the MS of eight ent-kaurane diterpenoids was explored, and their mass spectrum cleavage pathways were summarised and determined. Finally, the methanol extract of I. serra was studied using SWATH and identified by extracted ion chromatography (XIC). RESULTS: Compared to the traditional information-dependent acquisition (IDA) method, SWATH significantly improved the hit rate of ent-kaurane diterpenoids. With support from UHPLC separation and specific detection by tandem mass spectrometry (MS/MS), 48 ent-kaurane diterpenoids were successfully characterised and classified as ent-kaurane diterpenoids from a complex matrix. CONCLUSIONS: These combined qualitative methods were used to provide a potential approach for the characterisation of traditional Chinese medicine (TCM) and its preparations. Meanwhile, the SWATH provided a novel and reliable method for the structural characterisation of ent-kaurane diterpenoids from other complicated TCMs.


Assuntos
Diterpenos do Tipo Caurano , Diterpenos , Isodon , Cromatografia Líquida de Alta Pressão , Diterpenos/análise , Diterpenos do Tipo Caurano/análise , Isodon/química , Espectrometria de Massas em Tandem/métodos
13.
Angew Chem Int Ed Engl ; 61(24): e202112400, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34936187

RESUMO

Inorganic chiral hybrid nanostructures that embed chirality within distinct material compositions can create novel chiral properties and functionalities absent from achiral nanostructures; however, they remain largely unexplored. We report, for the first time, a class of chiral plasmonic metal-semiconductor core-shell nanostructures that employ structurally chiral nanoparticles as chirality inducing templates to grow functional shell materials, which allowed us to independently control material parameters such as core geometry and shell thickness, as well as handedness of the system. We experimentally and theoretically achieved enhanced and tunable chiroptical activity of the heterostructures as a result of the core-shell strong coupling effect. As a proof-of-concept demonstration, we demonstrate that the chiral hybrid nanostructures can drive chirality-dependent photocatalytic hydrogen generation under circularly polarized light. This study enables rational design and functionalization of chiral hybrid nanomaterials towards enhanced chiral light-matter interactions and chiral device applications.

14.
Anal Biochem ; 629: 114297, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34217704

RESUMO

Genuine regional drugs have played a vital role in clinical use for a long time. There are differences in traditional Chinese medicines (TCM) from different regions based on their chemical composition. Differences in chemical composition may lead to deviations in therapeutic effects. To our knowledge, to date, there are no effective methods for distinguishing genuine regional drugs based on the differences in their chemical composition. Therefore, establishing an analytical platform for distinguishing the compounds used in TCM from various geographical locations is essential. In this work, an integrated platform based on UPLC-Q-TOF-MS/MS combined with plant metabolomics approach was established for comprehensively distinguishing genuine regional drugs. Isodon rubescens (Hemsl.) Hara, a widely used herbal medicine of China, was chosen for this study and 24 samples from four geographical locations in China were collected. A total of 60 ent-kaurane diterpenoids were tentatively identified, and then the samples from four geographical origins were distinguished using PCA (principal component analysis) and PLS-DA (partial least squares discrimination analysis). Different compounds were identified among the samples collected from the four geographical locations, and 12 of them were regarded as marker compounds responsible for the distinction. Our study highlights the essence and predictive ability of metabolomics in detecting minute differences in the same varieties of TCM samples based on the levels and compositions of their metabolites. These results showed that the analysis using UHPLC-Q-TOF-MS/MS combined with metabolomics could be applied to distinguish the geographical origins and varieties of TCM.


Assuntos
Biomarcadores/análise , Diterpenos/análise , Medicamentos de Ervas Chinesas/análise , Isodon/química , Cromatografia Líquida de Alta Pressão , Análise dos Mínimos Quadrados , Medicina Tradicional Chinesa , Metabolômica , Análise Multivariada , Análise de Componente Principal , Espectrometria de Massas em Tandem
15.
Ther Drug Monit ; 43(6): 789-796, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33990504

RESUMO

OBJECTIVE: To perform therapeutic drug monitoring of total and free plasma valproic acid (VPA) concentrations in clinical samples and to analyze the related factors. METHODS: The total VPA concentration in plasma was determined by ultrahigh-performance liquid chromatography with precolumn derivatization with α-bromoacetophenone, and the free VPA concentration was determined by liquid chromatography-tandem mass spectrometry after the plasma was treated by hollow fiber centrifugal ultrafiltration. Regression analysis was performed to examine the associations between free plasma VPA, total plasma VPA, and the plasma protein binding rate. The impact of individual situations, outpatient or inpatient factors, and drug combinations on VPA concentrations were examined. RESULTS: Of the 569 clinical samples, 268 were inpatients and 301 were outpatients, and the total VPA concentration in 138 cases (24.2%) was lower than the effective treatment concentration range; the total and free VPA concentrations in outpatient samples were 11.0% and 26.1% higher than those of inpatients, respectively. There was no linear relationship between the free and total VPA concentrations. The relationship equation between the plasma protein binding rate and free VPA concentrations was as follows: Y = 0.0255X2 - 1.1357X + 97.429 (r = 0.8011). The total and free VPA concentrations were significantly decreased after the coadministration of phenobarbital (83.7% and 64.3% of the control group, P < 0.05) or carbapenem antibiotics (32.0% and 32.7% of the control group, P < 0.05). CONCLUSIONS: The total VPA concentrations in patients with epilepsy at our hospital was lower than the effective treatment concentration range, which was inadequate for epilepsy control; the total VPA concentrations of outpatients were higher than those of inpatients; as phenobarbital affects VPA metabolism, therapeutic drug monitoring is recommended. Carbapenem antibiotic coadministration with VPA should be avoided because carbapenem antibiotics can lead to the failure of VPA antiepileptic treatment.


Assuntos
Ultrafiltração , Ácido Valproico , Anticonvulsivantes , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem/métodos , Ultrafiltração/métodos
17.
Tumour Biol ; 37(9): 12889-12896, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27449042

RESUMO

There is increasing evidence supporting the cancer stem cell (CSC) hypothesis, which suggests that a population of tumor cells with stem cell characteristics is responsible for tumor growth, resistance, and recurrence as well as drug resistance. In colorectal cancer, the CD133 antigen defines distinct cell subpopulations that are rich in tumor-initiating cells; however, the drug resistance properties of these CD133-positive cells have not been well defined. The breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2) is present on the plasma membrane of many types of human cancer cells and contributes to multidrug resistance during chemotherapy. The results of the present study showed that ABCG2 is expressed in CD133-positive CSCs from human colorectal tumors. Furthermore, the downregulation of ABCG2 expression inhibited the self-renewal capacity of these cells, and significantly enhanced the efficacy of chemotherapy-induced apoptosis in LS174T colon adenocarcinoma cells and CD133-positive colorectal carcinoma cells. Together, these data show that ABCG2 expression correlates with the presence of CD133-positive cancer cells, and thus is a possible therapeutic target for colorectal cancer.


Assuntos
Antígeno AC133/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Autorrenovação Celular , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Feminino , Fluoruracila/farmacologia , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Anal Biochem ; 511: 61-73, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27503750

RESUMO

Oridonin (ORI) is an active natural ent-kaurene diterpenoid ingredient with notable anti-cancer and anti-inflammation activities. Currently, a strategy was developed to identify metabolites and to assess the metabolic profiles of ORI in vitro using ultra-high-performance liquid chromatography-Triple/time-of-flight mass spectrometry (UPLC-Triple-TOF-MS/MS). Meanwhile, the metabolism differences of ORI in the liver microsomes of four different species were investigated using a principal component analysis (PCA) based on the metabolite absolute peak area values as the variables. Based on the proposed methods, 27 metabolites were structurally characterized. The results indicate that ORI is universally metabolized in vitro, and the metabolic pathway mainly includes dehydration, hydroxylation, di-hydroxylation, hydrogenation, decarboxylation, and ketone formation. Overall, there are obvious inter-species differences in types and amounts of ORI metabolites in the four species. These results will provide basic data for future pharmacological and toxicological studies of ORI and for other ent-kauranes diterpenoids. Meanwhile, studying the ORI metabolic differences helps to select the proper animal model for further pharmacology and toxicological assessment.


Assuntos
Diterpenos do Tipo Caurano/farmacocinética , Microssomos Hepáticos/metabolismo , Espectrometria de Massas em Tandem/métodos , Animais , Humanos
19.
Zhongguo Zhong Yao Za Zhi ; 41(2): 250-256, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28861970

RESUMO

A quick HPLC-ESI-MS/MS method was established for simultaneous determination of four major diterpenoids in Rabdosia japonica var.glaucocalyx, including glaucocalyxin A, oridonin, hebeirubesensin and enmenol. Analysis was performed on an Agilent ZORBAX SB-C18(4.6 mm×250 mm, 5 µm ) column eluted in a gradient program with methanol and water. The flow rate was 0.8 mL•min⁻¹. Multiple reaction monitoring (MRM) scanning mode was performed in negative ion switching mode to apply for the quantitative determination. The calibration curves for the above four compounds were linear in corresponding injection amount. The average recoveries of the compounds ranged from 92.40% to 105.9%, with RSDs of 1.7%-6.5%. The method is simple, rapid, accurate with good repeatability, which can provide a reference for overcalling evaluation the quality of R. japonica var.glaucocalyx. The result of cluster analysis- showed that the quality of R. japonica glaucocalyx var. greatly varied between areas and parts.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Diterpenos/química , Medicamentos de Ervas Chinesas/química , Isodon/química , Espectrometria de Massas em Tandem/métodos
20.
Zhongguo Zhong Yao Za Zhi ; 40(24): 4884-9, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27245038

RESUMO

A quick HPLC-ESI-MS/MS method was established for simultaneous determination of three chemical compositions in Usnea, including usnic acid, diffractaic acid, and ramalic acid. The separation was performed on a chromatographic column of Agilent ZORBAX SB-C, (4.6 mm x 250 mm, 5 µm), and the mobile phase was methanol (0.05% formic acid)-0.05% formic acid solution (4 mmol ammonium acetate), with an isocratic elution at a flow rate of 0.8 ml · min⁻¹. Multiple reaction monitoring scanning mode (MRM) was performed combined with the ion switching technology in positive and negative ion switching mode to apply for the quantitative determination. The calibration curves for the above three compounds were linear in corresponding injection amount. Their average recoveries were 95.0%-105.1%, with RSDs of 1.1%-5.2%. The method was simple, rapid, accurate with high repeatability, which could provide a reference for overcalling evaluation the quality of Usnea.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hidroxibenzoatos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Usnea/química
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