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1.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679709

RESUMEN

Land surface temperatures (LST) are vital parameters in land surface-atmosphere interactions. Constrained by technology and atmospheric interferences, LST retrievals from various satellite sensors usually return missing data, thus negatively impacting analyses. Reconstructing missing data is important for acquiring gap-free datasets. However, the current reconstruction methods are limited for maintaining spatial details and high accuracies. We developed a new gap-free algorithm termed the spatial feature-considered random forest regression (SFRFR) model; it builds stable nonlinear relationships to connect the LST with related parameters, including terrain elements, land coverage types, spectral indexes, surface reflectance data, and the spatial feature of the LST, to reconstruct the missing LST data. The SFRFR model reconstructed gap-free LST data retrieved from the Landsat 8 satellite on 27 July 2017 in Wuhan. The results show that the SFRFR model exhibits the best performance according to the various evaluation metrics among the SFRFR, random forest regression and spline interpolation, with a coefficient of determination (R2) reaching 0.96, root-mean-square error (RMSE) of 0.55, and mean absolute error (MAE) of 0.55. Then, we reconstructed gap-free LST data gathered in Wuhan from 2016 to 2021 to analyze urban thermal environment changes and found that 2020 presented the coolest temperatures. The SFRFR model still displayed satisfactory results, with an average R2 of 0.91 and an MAE of 0.63. We further discuss and discover the factors affecting the visual performance of SFRFR and identify the research priority to circumvent these disadvantages. Overall, this study provides a simple, practical method for acquiring gap-free LST data to help us better understand the spatiotemporal LST variation process.


Asunto(s)
Algoritmos , Monitoreo del Ambiente , Temperatura , Monitoreo del Ambiente/métodos , Ciudades , China
2.
J Transl Med ; 20(1): 235, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35590418

RESUMEN

BACKGROUND: Necroptosis is a new form of programmed cell death that is associated with cancer initiation, progression, immunity, and chemoresistance. However, the roles of necroptosis-related genes (NRGs) in colorectal cancer (CRC) have not been explored comprehensively. METHODS: In this study, we obtained NRGs and performed consensus molecular subtyping by "ConsensusClusterPlus" to determine necroptosis-related subtypes in CRC bulk transcriptomic data. The ssGSEA and CIBERSORT algorithms were used to evaluate the relative infiltration levels of different cell types in the tumor microenvironment (TME). Single-cell transcriptomic analysis was performed to confirm classification related to NRGs. NRG_score was developed to predict patients' survival outcomes with low-throughput validation in a patients' cohort from Fudan University Shanghai Cancer Center. RESULTS: We identified three distinct necroptosis-related classifications (NRCs) with discrepant clinical outcomes and biological functions. Characterization of TME revealed that there were two stable necroptosis-related phenotypes in CRC: a phenotype characterized by few TME cells infiltration but with EMT/TGF-pathways activation, and another phenotype recognized as immune-excluded. NRG_score for predicting survival outcomes was established and its predictive capability was verified. In addition, we found NRCs and NRG_score could be used for patient or drug selection when considering immunotherapy and chemotherapy. CONCLUSIONS: Based on comprehensive analysis, we revealed the potential roles of NRGs in the TME, and their correlations with clinicopathological parameters and patients' prognosis in CRC. These findings could enhance our understanding of the biological functions of necroptosis, which thus may aid in prognosis prediction, drug selection, and therapeutics development.


Asunto(s)
Neoplasias Colorrectales , Microambiente Tumoral , Biomarcadores de Tumor/genética , China , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Necroptosis/genética , Pronóstico , Transcriptoma/genética
3.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2681-2688, 2022 May.
Artículo en Zh | MEDLINE | ID: mdl-35718487

RESUMEN

Scutellariae Radix(SR), derived from the dried root of Scutellaria baicalensis in the family Lamiaceae, commonly serves as Chinese medicinal material. Affected by producing areas, growing years, and harvesting periods, the quality of SR fluctuates in the market. However, baicalin≥9% in SR required in the Chinese Pharmacopoeia(2020 edition) can only determine the qualified SR but cannot identify high-quality SR. To improve the quality control methods of SR, the present study analyzed the accumulation of metabolites in SR of different growth years by plant metabolomics, and identified 28 metabolites increasing with growth years(1-3 years). Subsequently, 14 main metabolites were quantitatively analyzed by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry(UPLC-QQQ-MS). Among them, baicalin, wogonoside, baicalein, and wogonin with high content and good activity were selected as the index components of SR for quality evaluation. A high-performance liquid chromatography(HPLC) method was established to determine the content of four index components in 32 batches of SR from different producing areas, harvesting perio-ds, and growth years. The results showed that the growth years could greatly affect the content of index components. The total content of four index components in 2-year SR was the highest, followed by the 3-/4-year SR and 1-year SR. Based on HPLC data and verification results by enterprises, baicalin ≥12.0%, wogonoside ≥2.3%, baicalein ≥0.1%, and wogonin ≥0.03% were proposed as the evaluation criteria for the high-quality SR. The findings of this study are expected to provide a basis for improving the quality of SR.


Asunto(s)
Medicamentos Herbarios Chinos , Flavanonas , Cromatografía Líquida de Alta Presión/métodos , Flavonoides , Metabolómica , Extractos Vegetales , Scutellaria baicalensis
4.
Oncologist ; 25(3): 244-251, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32162825

RESUMEN

BACKGROUND: The role of horizontal growth index of tumor size in survival prediction is still underappreciated in colon cancer because of the identification of vertical infiltration index reflected by T stage. We sought to reveal the impact of T stage on the prognostic and predictive value of tumor size in colon cancer. MATERIALS AND METHODS: Data of patients with stage I-III colon cancer were extracted from Surveillance, Epidemiology, and End Results Program (SEER) and Fudan University Shanghai Cancer Center (FUSCC) databases. Harrell's concordance index (c-index) and time-dependent receiver operating characteristic curve (ROC) were used to analyze the discriminative ability of prognostic factors. RESULTS: Stratified analyses based on T stage found that the increase of T stage significantly and negatively repressed the effect of tumor size on death and recurrence risk. In addition, tumor size showed the greatest hazard ratio of cancer-specific death and relapse in T1 colon cancer. Even more importantly, the discriminatory ability of tumor size outperformed any other widely accepted prognostic clinical features in predicting cancer-specific survival (SEER: c-index 0.637, area under the ROC [AUC] 0.649; FUSCC: c-index 0.673, AUC 0.686) and disease-free survival (FUSCC: c-index 0.645, AUC 0.656) in T1 stage colon cancer. CONCLUSION: Tumor size is a critical clinical factor with considerable prognostic and predictive value for T1 colon cancer, and it should be selectively incorporated into the current staging system to facilitate prediction of death and recurrence risk. IMPLICATIONS FOR PRACTICE: To date, no consensus has been reached about the prognostic and predictive value of tumor size in colon cancer. Although tumor size is an independent prognostic factor for patients with colon cancer, the impact of tumor size on death or recurrence risk decreased notably with the increase of T stage. More importantly, the discriminative ability of tumor size outperformed any other clinical factors including N stage in patients with T1 colon cancer. Therefore, tumor size should be recommended to be incorporated into current staging systems to facilitate prognosis prediction for patients with T1 colon cancer.


Asunto(s)
Neoplasias del Colon , Recurrencia Local de Neoplasia , China , Neoplasias del Colon/patología , Humanos , Estimación de Kaplan-Meier , Estadificación de Neoplasias , Pronóstico
5.
BMC Cancer ; 20(1): 95, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32013887

RESUMEN

BACKGROUND: Neuromedin U (NMU) is a neuropeptide belonging to the neuromedin family. Recently, significant associations between NMU and several cancers have been reported. However, no studies have examined the association between NMU and hepatocellular carcinoma (HCC). The purpose of this study was to examine the role of NMU in HCC. METHODS: An enzyme-linked immunosorbent assay was used to measure the level of NMU protein in the sera of patients with hepatic hemangioma and HCC. NMU and cytokine mRNA expression was assessed in HCC samples via RT-qPCR. A tissue microarray consisting of 228 HCC peri- and intra-tumor tissues was used to detect NMU expression via immunohistochemical analysis. The association between NMU expression and overall survival (OS) and disease-free survival (DFS) was analyzed by Kaplan-Meier curves, the log-rank test, and Cox proportional hazard model. RESULTS: The level of NMU protein was increased in the sera of HCC patients (p = 0.006). NMU was expressed in intercellular space, rather than in hepatocytes or HCC cells. The prognosis of HCC patients with high NMU expression in peri-tumor tissue was significantly poorer than that of patients with low NMU expression (OS: p = 0.002, DFS: p = 0.033). Peri-tumor NMU expression was also a significant independent prognostic factor for OS (hazard ratio: 1.541, 95% confidence interval: 1.092-2.175, p = 0.014). The level of NMU expression was positively associated with M2 macrophage percentage and the levels of type-2 inflammatory cytokines in HCC tissue. CONCLUSIONS: NMU may serve as a novel prognostic biomarker for HCC patients, although further validation is needed in the future. The activation of M2 macrophages and a type-2 inflammatory response may involve in the role of NMU in patients with HCC.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Neuropéptidos/metabolismo , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Citocinas/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Neuropéptidos/genética , Pronóstico , Análisis de Supervivencia , Análisis de Matrices Tisulares , Regulación hacia Arriba
6.
Int J Colorectal Dis ; 35(8): 1575-1585, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32417937

RESUMEN

PURPOSE: Bone metastasis (BM) can obviously affect the quality of life of patients in colorectal cancer (CRC), and the whole management of patients with BM would be attractive in current clinical practice. METHODS: A total of 52,859 patients during 2010-2015 were collected from Surveillance, Epidemiology, and End Results (SEER) database. After propensity score matching (PSM), cancer-specific survival (CCS) and overall survival (OS) with BM were adopted to assess survival probability difference. Logistic regression was used to identify risk factors for BM; COX proportion hazard regression was applied to explore prognosticators for OS in patients with BM. Subsequently, nomograms were constructed and receiver operating curves (ROCs) were used to confirm the validation of nomogram. RESULTS: Three hundred and forty-two (0.65%) patients were diagnosed with synchronous BM. After PSM, 16 variables were balanced. Tumor site, histology, grade, T stage, N stage, CEA, radiochemotherapy, surgery, and liver/lung/brain metastases were associated with BM, and histology, grade, T stage, N stage, CEA, chemotherapy, surgery, and liver/lung metastases were prognosticators for BM survival. Nomograms were applied and the ROC curve proved the predictive effects. CONCLUSION: CRC patients with BM have worse real-world survival. Nomogram can predict incidence of BM in CRC patients and survival among patients with BM.


Asunto(s)
Neoplasias Óseas , Neoplasias Colorrectales , Neoplasias Colorrectales/patología , Humanos , Estadificación de Neoplasias , Nomogramas , Pronóstico , Calidad de Vida
7.
Int J Colorectal Dis ; 35(2): 317-322, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31858220

RESUMEN

PURPOSE: With emphasis of surgical management, the lymph node (LN) status has been advocated to predict prognosis in colon cancer with distant metastatic. Therefore, we tend to compare the prognostic performance of American Joint Committee on Cancer (AJCC) N-staging relative to lymph node ratio (LNR), log odds of metastatic lymph nodes (LODDS), and N-score in stage IV colon cancer. METHODS: About 20,961 patients who underwent primary surgical resection for stage IV colon cancer were extracted from Surveillance, Epidemiology, and End Results (SEER) Program database. Harrell's C statistic (C-index) and Akaike's Information Criterion (AIC) were used to distinguish the prognostic performance of the different LN-staging schemes. RESULTS: Of the 20,961 patients, 17,043 (81.3%) had been with lymph node metastasis, and the median number of examined lymph nodes (ELNs) was 15. When assessed as continuous values, the LODDS shown as the best system with greatest discriminatory power (C-index, 0.6241; AIC, 29114.29) generally and each subgroups divided by ELNs. When modeled as categorical cutoff variables for further clinical usage, the 8th AJCC N-stage outperformed the other three schemes with either ELNs less than 12 (C-index, 0.5770; AIC, 8992.638), between 12 and 25 (C-index, 0.6084; AIC, 13905.72), or more than 25(C-index, 0.6192; AIC, 3138.018) with increasing C-index and less AIC value. CONCLUSIONS: When assessed as categorical variables, N-stage performed superiorly regardless of ELNs. When assessed as a continuous variable, LODDS exhibited good discriminative ability and goodness of fit in predicting survival for colon cancer patients regardless of ELNs.


Asunto(s)
Neoplasias del Colon/patología , Ganglios Linfáticos/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colectomía , Neoplasias del Colon/mortalidad , Neoplasias del Colon/cirugía , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Programa de VERF , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Adulto Joven
8.
Cancer Cell Int ; 19: 355, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31889907

RESUMEN

BACKGROUND: The purpose of this study was to build functional nomograms based on significant clinicopathological features to predict cause-specific survival (CSS) and overall survival (OS) in patients with stage I-III colon cancer. METHODS: Data on patients diagnosed with stage I-III colon cancer between 2010 and 2015 were downloaded from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox analyses were used to identify independent prognostic factors, which were used to construct nomograms to predict the probabilities of CSS and OS. The performance of the nomogram was assessed by C-indexes, receiver operating characteristic (ROC) curves and calibration curves. Decision curve analysis (DCA) was used to compare clinical usage between the nomogram and the tumor-node-metastasis (TNM) staging system. RESULTS: Based on the univariate and multivariate analyses, features that correlated with survival outcomes were used to establish nomograms for CSS and OS prediction. The nomograms showed favorable sensitivity at predicting 1-, 3-, and 5-year CSS and OS, with a C-index of 0.78 (95% confidence interval (CI) 0.77-0.80) for CSS and 0.74 (95% CI 0.73-0.75) for OS. Calibration curves and ROC curves revealed excellent predictive accuracy. The clinically and statistically significant prognostic performance of the nomogram generated with the entire group of patients and risk scores was validated by a stratified analysis. DCA showed that the nomograms were more clinically useful than TNM stage. CONCLUSION: Novel nomograms based on significant clinicopathological characteristics were developed and can be used as a tool for clinicians to predict CSS and OS in stage I-III colon cancer patients. These models could help facilitate a personalized postoperative evaluation.

9.
Int J Colorectal Dis ; 34(11): 1915-1924, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31642969

RESUMEN

BACKGROUND: The aim of this study is to evaluate the epidemiology of and prognostic factors for appendiceal carcinomas (ACs). METHODS: All cases of ACs registered in the Surveillance, Epidemiology, and End Results (SEER) database from 1973 to 2014 were retrospectively identified in this study. Age-adjusted incidence and survival rates were calculated. RESULTS: We analyzed 7170 patients with ACs. We observed a significant increase in the reported annual age-adjusted incidence of ACs from 1973 (0.18/100,000) to 2014 (1.11/100,000). The elevation of the incidence was noted in all the histological types, stages, and grades. The most common histological type varied by race, with the appendiceal mucinous adenocarcinoma (AMA) being the most common in white, Asian/Pacific Islander, and American Indian/Alaskan Native patients, and the appendiceal adenocarcinoma (AA) being the most common in African American patients. In multivariate analysis of patients with all ACs, gender (P < 0.001), year of diagnosis (P < 0.001), age (P < 0.001), race (P < 0.001), tumor grade (P < 0.001), disease stage (P < 0.001), retrieved regional lymph nodes (P < 0.001), type of surgery performed (P = 0.002), and histologic subtype (P < 0.001) were predictors of outcome. Survival time for all ACs increased from the 1973-1993 period to the 1994-2014 period (HR 0.76; 95% CI, 0.69 to 0.85). Additionally, the 5-year survival rates were 88% for malignant carcinoid, 70% for goblet cell carcinoid, 51% for colonic type adenocarcinoma, 59% for mucinous adenocarcinoma, and 25% for signet ring cell type. CONCLUSIONS: We observed increased reported incidence of ACs and increased survival durations over time, suggesting that clinicians pay more attention to ACs and mastering the characteristic of these tumors.


Asunto(s)
Neoplasias del Apéndice/epidemiología , Adulto , Anciano , Neoplasias del Apéndice/diagnóstico , Neoplasias del Apéndice/patología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Grupos Raciales , Estudios Retrospectivos , Programa de VERF , Análisis de Supervivencia
10.
Molecules ; 24(9)2019 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-31083471

RESUMEN

Pomegranate peel pectin is an important acidic anionic plant polysaccharide which can be used as a natural emulsifier. In order to study its emulsifying properties, this paper systematically analyses pomegranate peel pectin samples from Chinese Xinjiang, Sichuan and Yunnan provinces, through rheometer, interfacial rheometer, Zetasizer Nano-ZS and mastersizer. It is shown that pomegranate peel pectin can effectively reduce the oil-water interfacial tension, reaching an emulsion droplet size of only 0.507 µm, 0.669 µm and 0.569 µm, respectively, while the pectin concentration is 1.5% and the oil phase (MCT) is 10%. It has also shown that the extreme conditions of pH and ion strength can not significantly change its emulsion stability. However, freeze-thaw cycles can cause the pomegranate peel pectin emulsion to become less stable. Furthermore, the effects of decolourization, protein removal and dialysis on the emulsifying properties of pomegranate peel pectin are investigated using mastersizer rheometer and interfacial rheometer. It is found that the protein and pigment in pomegranate peel pectin have little effect on its emulsifying properties, while the results from dialyzed pectin show that the small molecule substances can reduce the emulsion particle size and increase the emulsion stability. The research outcomes of this study provide technical support for the further application of pomegranate peel pectin in the food industry.


Asunto(s)
Emulsionantes/química , Frutas/química , Lythraceae/química , Pectinas/análisis , Reología
11.
Anal Bioanal Chem ; 410(18): 4419-4435, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29704033

RESUMEN

Traditional Chinese medicines (TCMs) are undoubtedly treasured natural resources for discovering effective medicines in treating and preventing various diseases. However, it is still extremely difficult for screening the bioactive compounds due to the tremendous constituents in TCMs. In this work, the chemical composition of toad venom was comprehensively analyzed using ultra-high performance liquid chromatography (UPLC) coupled with high-resolution LTQ-Orbitrap mass spectrometry and 93 compounds were detected. Among them, 17 constituents were confirmed by standard substances and 8 constituents were detected in toad venom for the first time. Further, a compound database of toad venom containing the fullest compounds was further constructed using UPLC coupled with high-sensitivity Qtrap MS. Then a target cell-based approach for screening potential bioactive compounds from toad venom was developed by analyzing the target cell extracts. The reliability of this method was validated by negative controls and positive controls. In total, 17 components in toad venom were discovered to interact with the target cancer cells. Further, in vitro pharmacological trials were performed to confirm the anti-cancer activity of four of them. The results showed that the six bufogenins and seven bufotoxins detected in our research represented a promising resource to explore bufogenins/bufotoxins-based anticancer agents with low cardiotoxic effect. The target cell-based screening method coupled with the compound database of toad venom constructed by UPLC-Qtrap-MS with high sensitivity provide us a new strategy to rapidly screen and identify the potential bioactive constituents with low content in natural products, which was beneficial for drug discovery from other TCMs. ᅟ Graphical abstract.


Asunto(s)
Venenos de Anfibios/química , Productos Biológicos/análisis , Bufonidae , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Animales , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Límite de Detección , Células MCF-7 , Reproducibilidad de los Resultados
12.
Molecules ; 23(11)2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30424008

RESUMEN

Macamides are very important secondary metabolites produced by Lepidium meyenii Walp, which possess multiple bioactivities, especially in the neuronal system. In a previous study, we observed that macamides exhibited excellent effects in the recovery of injured nerves after 1-methyl-4-phenylpyridinium (MPP⁺)-induced dopaminergic neuronal damage in zebrafish. However, the mechanism underlying this effect remains unclear. In the present study, we observed that N-benzylhexadecanamide (XA), which is a typical constituent of macamides, improved the survival rate of neurons in vitro. We determined the concentration of neurotransmitters in MN9D cells and used it in conjunction with an integrated proteomics and lipidomics approach to investigate the mechanism underlying the neuroprotective effects of XA in an MPP⁺-induced neurodegeneration cell model using QqQ MS, Q-TOF MS, and Orbitrap MS. The statistical analysis of the results led to the identification of differentially-expressed biomarkers, including 11 proteins and 22 lipids, which may be responsible for the neuron-related activities of XA. All these potential biomarkers were closely related to the pathogenesis of neurodegenerative diseases, and their levels approached those in the normal group after treatment with XA. Furthermore, seven lipids, including five phosphatidylcholines, one lysophosphatidylcholine, and one phosphatidylethanolamine, were verified by a relative quantitative approach. Moreover, four proteins (Scarb2, Csnk2a2, Vti1b, and Bnip2) were validated by ELISA. The neurotransmitters taurine and norepinephrine, and the cholinergic constituents, correlated closely with the neuroprotective effects of XA. Finally, the protein⁻lipid interaction network was analyzed. Based on our results, the regulation of sphingolipid metabolism and mitochondrial function were determined to be the main mechanisms underlying the neuroprotective effect of XA. The present study should help us to better understand the multiple effects of macamides and their use in neurodegenerative diseases.


Asunto(s)
Lípidos/química , Metabolómica , Fármacos Neuroprotectores/química , Alcamidas Poliinsaturadas/química , Proteómica , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Metabolómica/métodos , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Neurotransmisores/química , Neurotransmisores/farmacología , Alcamidas Poliinsaturadas/farmacología , Proteómica/métodos , Transducción de Señal
14.
Planta Med ; 83(16): 1281-1288, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28399592

RESUMEN

Protoberberine alkaloids including berberine, palmatine, jatrorrhizine, coptisine, and epiberberine are major components in many medicinal plants. They have been widely used for the treatment of cancer, inflammation, diabetes, depression, hypertension, and various infectious areas. However, the metabolism of five protoberberine alkaloids among different species has not been clarified previously. In order to elaborate on the in vitro metabolism of them, a comparative analysis of their metabolic profile in rat, rhesus monkey, and human liver microsomes was carried out using ultrahigh-performance liquid chromatography coupled with a high-resolution linear trap quadrupole-Orbitrap mass spectrometer (UHPLC-electrospray ionization-Orbitrap MS) for the first time. Each metabolite was identified and semiquantified by its accurate mass data and peak area. Fifteen metabolites were characterized based on accurate MS/MS spectra and the proposed MS/MS fragmentation pathways including demethylation, hydroxylation, and methyl reduction. Among them, the content of berberine metabolites in human liver microsomes was similar with those in rhesus monkey liver microsomes, whereas berberine in rat liver microsomes showed no demethylation metabolites and the content of metabolites showed significant differences with that in human liver microsomes. On the contrary, the metabolism of palmatine in rat liver microsomes resembled that in human liver microsomes. The content of jatrorrhizine metabolites presented obvious differences in all species. The HR-ESI-MS/MS fragmentation behavior of protoberberine alkaloids and their metabolic profile in rat, rhesus monkey, and human liver microsomes were investigated for the first time. The results demonstrated that the biotransformation characteristics of protoberberine alkaloids among different species had similarities as well differences that would be beneficial for us to better understand the pharmacological activities of protoberberine alkaloids.


Asunto(s)
Alcaloides de Berberina/metabolismo , Microsomas Hepáticos/metabolismo , Animales , Alcaloides de Berberina/química , Cromatografía Líquida de Alta Presión/métodos , Humanos , Técnicas In Vitro , Macaca mulatta , Masculino , Redes y Vías Metabólicas , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray/métodos
15.
Anal Bioanal Chem ; 408(10): 2485-95, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26869342

RESUMEN

Bufadienolides, a class of polyhydroxy steroids, exhibit significant antitumor activity. In this study, a total of 39 metabolites from 10 bufadienolides were detected and identified by ultrahigh-performance liquid chromatography (UHPLC) coupled with an LTQ Orbitrap mass spectrometer. The results showed that hydroxylation and dehydrogenation were the major metabolic pathways of bufadienolides in human liver microsomes (HLMs). CYP3A4 was found to be the major metabolic enzyme and CYP2D6 only mediated the dehydrogenation reaction. A systematic validated cytotoxicity evaluation method for bufadienolide metabolites at equal equivalents was established. Hellebrigenin (1), hellebrigenol (2), arenobufagin (3), bufotalin (5), and bufalin (6) were selected to determine their cytotoxicity against HepG2 cells before and after incubation in HLMs. All the test samples were enriched by a validated solid-phase extraction (SPE) method. Although the cytotoxicities of metabolites were weaker than those of the parent compounds to different degrees, their effects were still strong.


Asunto(s)
Bufanólidos/metabolismo , Microsomas Hepáticos/metabolismo , Cromatografía Líquida de Alta Presión , Células Hep G2 , Humanos , Espectrometría de Masas en Tándem
16.
Biomed Chromatogr ; 30(11): 1757-1765, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27106066

RESUMEN

Marsdenia tenacissima, which is widely used as an anticancer herb in traditional Chinese medicine, has been shown to possess anticancer activity. However, its metabolic profile is poorly investigated. Tenacigenin B is the major steroidal skeleton of C-21 steroids in M. tenacissima. Tenacissoside H and Tenacissoside I are detected at relatively high levels in M. tenacissima. Therefore, we studied their metabolic characteristics in human liver microsomes by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry. Fourteen metabolites were tentatively identified by accurate mass measurement and MS/MS fragmentation behavior. It was found that hydroxylation reactions were the major metabolic pathway of Tenacissoside H and Tenacissoside I in human liver microsomes, whereas the metabolic pathway of Tenacigenin B involved dehydrogenation reactions. This is the first time that the metabolic profile of C-21 steroids from M. tenacissima has been explored in human liver microsomes, which is of great significance for subsequent pharmacokinetic and interaction research. Biotransformation in vivo or in vitro may influence the structure of a compound and change its activity. Identification of their fragmentation behaviors and metabolites provides valuable and new information for further understanding the anti-tumor activity of M. tenacissima. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Antineoplásicos Fitogénicos/metabolismo , Microsomas Hepáticos/metabolismo , Fitosteroles/metabolismo , Saponinas/metabolismo , Esteroides/metabolismo , Antineoplásicos Fitogénicos/química , Cromatografía Líquida de Alta Presión/métodos , Humanos , Marsdenia/química , Redes y Vías Metabólicas , Metabolómica/métodos , Fitosteroles/química , Saponinas/química , Esteroides/química , Espectrometría de Masas en Tándem/métodos
17.
Rapid Commun Mass Spectrom ; 29(21): 2045-56, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26443405

RESUMEN

RATIONALE: Limonoids, characterized by a triterpenoid skeleton with a furan ring, are unique secondary metabolites widely distributed in the families of Rutaceae, particularly in Citrus species and Meliaceae. Studies on health benefits have demonstrated that limonoids have a range of biological activities. Dietary intake of citrus limonoids may provide a protective effect against the onset of various cancers and other xenobiotic related diseases. However, few studies about the metabolic profiles of limonoids have been carried out. METHODS: The objectives of this study were to investigate the metabolic profiles of four limonoids (limonin, obacunone, nominin and gedunin) in human liver microsomes (HLMs) using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC/HRMS) and to identify the cytochrome P450 (CYP) enzymes involved in the formation of their metabolites by recombinant human CYP enzymes. RESULTS: Based on the accurate HR-MS/MS spectra and the proposed MS/MS fragmentation pathways, four metabolites of limonin (M1-1, M1-2, M1-3 and M1-4), eight metabolites ofobacunone (M2-1, M2-2, M2-3, M2-4, M2-5, M2-6, M2-7 and M2-8), six metabolites of nominin (M3-1, M3-2, M3-3, M3-4, M3-5 and M3-6) and three metabolites of gedunin (M4-1, M4-2 and M4-3) in HLMs were tentatively identified and the involved CYPs were investigated. CONCLUSIONS: The results demonstrated that reduction at C-7 and C-16, hydroxylation and reaction of glycine with reduction limonoids were the major metabolic pathways of limonoids in HLMs. Among them, glycination with reduction was the unique metabolic process of limonoids observed for the first time. CYP2D6 and CYP3A4 played an important role in the isomerization and glycination of limonoids in HLMs, whereas other CYP isoforms were considerably less active. The results might help to understand the metabolic process of limonoids in vitro such as the unidentified metabolites of limonin glucoside observed in the medium of microbes and the biotransformation of limonin in juices. Moreover, it would be beneficial for us to further study the pharmacokinetic behavior of limonoids in vivo systematically.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Limoninas/química , Limoninas/metabolismo , Espectrometría de Masas/métodos , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Humanos , Estructura Molecular
18.
Xenobiotica ; 45(4): 302-11, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25369727

RESUMEN

1. Zebrafish has been used in metabolic study of drugs as a powerful tool in recent years. In this study, we make a feasible metabolism investigation of five protoberberine alkaloids (PBAs) applied in zebrafish model for the first time, including berberine (BBR), palmatine (PAL), jatrorrhizine (JAT), coptisine (COP) and epiberberine (EBBR). 2. After exposure for 24 hours, 19 metabolites were identified by LTQ Orbitrap mass spectrometer, including 9 phase I metabolites and 10 phase II metabolites. Demethylation, hydroxylation, sulfation and glucuronidation were the major metabolic transformation of PBAs in zebrafish, which were similar to mammals. Compared with reported literatures, BBR and JAT showed high consistency between human and zebrafish in metabolic pathways. 3. To our knowledge, this is the first time to study in vivo metabolism of COP, which provides useful information to other researchers. 4. This study indicated that zebrafish model is feasible and reasonable to predict the metabolism of PBAs. It showed great potential for developing a novel and rapid method for predicting the metabolism of trace compounds of botanical drugs, with the advantages of lower cost, higher performance and easier set up.


Asunto(s)
Alcaloides de Berberina/metabolismo , Berberina/análogos & derivados , Animales , Berberina/metabolismo , Cromatografía Líquida de Alta Presión , Metabolómica , Modelos Animales , Espectrometría de Masas en Tándem , Pez Cebra
19.
Rapid Commun Mass Spectrom ; 28(21): 2292-300, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25279742

RESUMEN

RATIONALE: Limonin and obacunone are two major limonoids distributed in the Rutaceae and Meliaceae families. Their defined anti-tumor activity is closely connected with the furan ring and the multi-carbonyls in their structures. In vivo and in vitro biotransformations may influence their structures and further change their effects. The metabolic profiles of limonin and obacunone have not been studied previously. In order to clarify their in vivo and in vitro metabolism, a comparative investigation of their metabolic pathways in five different species of liver microsomes and zebrafish was carried out. METHODS: In the present study, ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC/HRMS) and related electrospray ionization (ESI) tandem mass spectrometric (MS/MS) dissociation of limonin and obacunone were applied for the analysis. Each metabolite was identified by its accurate mass data. Human liver microsomes (HLMs), monkey liver microsomes (MLMs), dog liver microsomes (DLMs), rat liver microsomes (RLMs), mice liver microsomes (XLMs) and zebrafish were included in the biotransformations. RESULTS: One phase I metabolite of limonin (M1-1) and two phase I metabolites of obacunone (M2-1, M2-2) were identified by accurate mass measurement and MS/MS fragmentation behaviors. A reduction reaction was regarded as the major metabolic pathway of limonoids in liver microsomes. The reduction reaction site of M1-1 and M2-1 was at the C-16 carbonyl, while for M2-2 it was at C-7. M1-1 was the major and unique metabolite of limonin and the metabolic rate of limonin varied from 11.5% to 17.8% in liver microsomes (LMs). M2-2 was the main metabolite of obacunone in LMs and zebrafish. M1-1 and M2-1 were only detected in LMs while M2-2 was found in both LMs and zebrafish incubation systems. The metabolic rate of obacunone varied from 2.5% to 19.1% and the content of M2-2 was about five times higher than that of M2-1. CONCLUSIONS: The ESI-HR-MS/MS fragmentation behaviors of limonin and obacunone were investigated for the first time. A qualitative and semi-quantitative method was developed for the in vivo and in vitro metabolic analysis of limonin and obacunone. The results demonstrated that the metabolic processes of limonin and obacunone were different between LMs and zebrafish. However, both of these two parent compounds presented similar metabolic processes in five species of LMs. This was caused by the metabolic difference between mammals and fish or because limonin probably cannot be absorbed in zebrafish.


Asunto(s)
Benzoxepinas/química , Benzoxepinas/metabolismo , Limoninas/química , Limoninas/metabolismo , Microsomas Hepáticos/metabolismo , Animales , Benzoxepinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Perros , Humanos , Iones/análisis , Iones/química , Iones/metabolismo , Limoninas/análisis , Ratones , Modelos Moleculares , Ratas , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray/métodos , Pez Cebra
20.
Yao Xue Xue Bao ; 49(11): 1574-7, 2014 Nov.
Artículo en Zh | MEDLINE | ID: mdl-25757284

RESUMEN

Cinobufacino injection is purified from water extraction of the skin of Bufo bufo gargarizans, which has been widely used for various cancers in clinic with significant anti-tumor effects. Bufadienolides were regarded as the main active constituents of cinobufacino injection in previous reports. In present study, 6 bufadienolides were isolated and purified from Cinobufacino injection. Their structures were identified as 3-epi-ψ-bufarenogin (1), ψ-bufarenogin (2), 3-epi-arenobufagin (3), arenobufagin (4), 3-epi-gamabufotalin (5), and 3-oxo-arenobufagin (6), separately. Among them, 1 and 3 were new compounds, 5 and 6 were new natural products. Compounds 1, 2 and compounds 3, 4 were two pairs configuration isomers at C-3, separately.


Asunto(s)
Bufanólidos/aislamiento & purificación , Bufo bufo , Piel/química , Animales , Bufanólidos/química , Inyecciones
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