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1.
Chem Biodivers ; 21(5): e202400098, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38462532

RESUMEN

Curcumae Radix (CuR) is a traditional Chinese medicine that has been used in China for more than 1,000 years. It has the traditional efficacy of activating blood and relieving pain, promoting qi and relieving depression, clearing heart and cooling blood, and promoting gallbladder and removing jaundice. Based on this, many domestic and foreign scholars have conducted systematic studies on its chemical composition, pharmacological effects, toxicity and quality control. Currently, 250 compounds, mainly including terpenoids and curcuminoids, have been isolated and identified from CuR, which has pharmacological activities, including antitumor, anti-inflammatory and analgesic, antidepressant, hepatoprotective, hemostatic, hematopoietic, and treatment of diabetes mellitus. In modern clinical practice, CuR is widely used in the treatment of tumors, breast hyperplasia, hepatitis, and stroke. However, the generation of toxicity and clinical application of CuR and Caryophylli Flos, the determination of the concoction process of artifacts, the determination of specific Quality Marker, and the establishment of the quality control system of CuR, are problems that need to be solved urgently at present.


Asunto(s)
Curcuma , Control de Calidad , Humanos , Curcuma/química , Medicina Tradicional China , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Animales , Fitoquímicos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación
2.
Arch Pharm Res ; 47(3): 165-218, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38493280

RESUMEN

Astragali Radix (A. Radix) is the dried root of Astragalus membranaceus var. mongholicus (Bge) Hsiao or Astragalus membranaceus (Fisch.) Bge., belonging to the family Leguminosae, which is mainly distributed in China. A. Radix has been consumed as a tonic in China for more than 2000 years because of its medicinal effects of invigorating the spleen and replenishing qi. Currently, more than 400 natural compounds have been isolated and identified from A. Radix, mainly including saponins, flavonoids, phenylpropanoids, alkaloids, and others. Modern pharmacological studies have shown that A. Radix has anti-tumor, anti-inflammatory, immunomodulatory, anti-atherosclerotic, cardioprotective, anti-hypertensive, and anti-aging effects. It has been clinically used in the treatment of tumors, cardiovascular diseases, and cerebrovascular complications associated with diabetes with few side effects and high safety. This paper reviewed the progress of research on its chemical constituents, pharmacological effects, clinical applications, developing applications, and toxicology, which provides a basis for the better development and utilization of A. Radix.


Asunto(s)
Planta del Astrágalo , Botánica , Medicamentos Herbarios Chinos , Saponinas , Planta del Astrágalo/química , Astragalus propinquus/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/química , Saponinas/farmacología
3.
Nat Prod Res ; : 1-17, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372230

RESUMEN

The genus Helleborus belongs to the Ranunculaceae family, distributed in southeastern Europe and western Asia. In folk medicine, it is commonly used as an anti-inflammatory and analgesic medicine for rheumatoid arthritis and bruises. Through reviewing recent articles, it was found that two hundred and twenty-six compounds have been isolated and identified from the genus Helleborus. These compounds include steroids, flavonoids, phenylpropanoids, lignans, anthraquinones, phenolics and others. Among them, the main chemical constituents are steroids. Pharmacological studies show Helleborus has anti-cancer, immunomodulatory, anti-inflammatory, analgesic, anti-hyperglycaemic, antioxidant and antibacterial properties. This article reviews the botany, phytochemistry, pharmacological effects and clinical applications of the genus Helleborus. Hopefully, it will provide a reference for in-depth research and exploitation of the genus Helleborus.

4.
Am J Chin Med ; 51(8): 1983-2040, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37903715

RESUMEN

Ganoderma is the dried fruiting bodiy of Ganoderma lucidum (Leyss.ex Fr.) Karst. or Ganoderma sinense Zhao, Xu et Zhang, belonging to the family Polyporaceae, which grows mainly in tropical, subtropical, and temperate regions. As a traditional Chinese medicine, Ganoderma has been used in China for more than 2000 years because of its medicinal properties, such as relieving cough and asthma, providing nourishment, and strengthening. Currently, more than 470 natural compounds have been obtained from the fungus, mainly including terpenoids, steroids, alkaloids, phenols, and other types of compounds. Modern pharmacological studies have shown that Ganoderma has antitumor, anti-inflammatory, hypoglycemic, hypolipidemic, and immunomodulatory effects. It is mainly used in clinical practice for the treatment of Diabetic Nephropathy and malignant tumors, with few side effects and high safety. This paper reviews the progress of research on its chemical composition, pharmacological effects, and clinical applications, with the goal of providing a basis for the better development and utilization of Ganoderma.


Asunto(s)
Ganoderma , Neoplasias , Polyporaceae , Reishi , Triterpenos , Humanos , Ganoderma/química , Reishi/química , Neoplasias/tratamiento farmacológico , Medicina Tradicional China , Triterpenos/uso terapéutico
5.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3287-3293, 2023 Jun.
Artículo en Chino | MEDLINE | ID: mdl-37382013

RESUMEN

This paper aimed to study the chemical constituents from the root bark of Schisandra sphenanthera. Silica, Sephadex LH-20 and RP-HPLC were used to separate and purify the 80% ethanol extract of S. sphenanthera. Eleven compounds were identified by ~1H-NMR, ~(13)C-NMR, ESI-MS, etc., which were 2-[2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl]-propane-1,3-diol(1), threo-7-methoxyguaiacylglycerol(2),4-O-(2-hydroxy-1-hydroxymethylethyl)-dihydroconiferylalcohol(3), morusin(4), sanggenol A(5), sanggenon I(6), sanggenon N(7), leachianone G(8),(+)-catechin(9), epicatechin(10), and 7,4'-dimethoxyisoflavone(11). Among them, compound 1 was a new compound, and compounds 2-9 were isolated from S. sphenanthera for the first time. Compounds 2-11 were subjected to cell viability assay, and the results revealed that compounds 4 and 5 had potential cytotoxicity, and compound 4 also had potential antiviral activity.


Asunto(s)
Catequina , Schisandra , Corteza de la Planta , Antivirales , Bioensayo , Fenoles
6.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6408-6413, 2023 Dec.
Artículo en Chino | MEDLINE | ID: mdl-38211998

RESUMEN

The chemical constituents of Helleborus thibetanus were isolated and purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and semi-preparative RP-HPLC, and the structures of all compounds were identified by modern spectrographic technology(MS, NMR). The MTT method was used to measure the cytotoxicity of compounds 1-8. Twelve compounds were isolated from the roots and rhizomes of H. thibetanus and were identified as(25R)-22ß,25-expoxy-26-[(O-ß-D-glucopyranosyl)oxy]-1ß,3ß-dihydroxyfurosta-5-en(1), ß-sitosterol myristate(2), ß-sitosterol lactate(3), ß-sitosterol 3-O-ß-D-glucopyrannoside(4), 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one(5), 1,3,5-trimethoxybenzene(6), 7,8-dimethylbenzo pteridine-2,4(1H,3H)-dione(7), 1H-indole-3-carboxylic acid(8), p-hydroxy cinnamic acid(9), lauric acid(10), n-butyl α-L-arabinofuranoside(11) and methyl-α-D-fructofuranoside(12), respectively. Among them, compound 1 is a new compound and named thibetanoside L; compounds 2, 5-8, 11 are first isolated from the family Ranunculaceae; compound 12 is isolated from the genus Helleborus for the first time. The results of MTT assay showed that the IC_(50) values of compounds 1-8 against HepG2 and HCT116 cells were greater than 100 µmol·L~(-1).


Asunto(s)
Helleborus , Helleborus/química , Estructura Molecular , Raíces de Plantas/química , Rizoma/química , Espectroscopía de Resonancia Magnética
7.
J Pharm Pharmacol ; 74(12): 1718-1742, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36106816

RESUMEN

OBJECTIVES: The genus Reynoutria belonging to the family Polygonaceae is widely distributed in the north temperate zone and used in folk medicine. It is administered as a sedative, tonic and digestive, also as a treatment for canities and alopecia. Herein, we reported a review on traditional uses, phytochemistry and pharmacology reported from 1985 up to early 2022. All the information and studies concerning Reynoutria plants were summarized from the library and digital databases (e.g. ScienceDirect, SciFinder, Medline PubMed, Google Scholar, and CNKI). KEY FINDINGS: A total of 185 articles on the genus Reynoutria have been collected. The phytochemical investigations of Reynoutria species revealed the presence of more than 277 chemical components, including stilbenoids, quinones, flavonoids, phenylpropanoids, phospholipids, lactones, phenolics and phenolic acids. Moreover, the compounds isolated from the genus Reynoutria possess a wide spectrum of pharmacology such as anti-atherosclerosis, anti-inflammatory, antioxidative, anticancer, neuroprotective, anti-virus and heart protection. SUMMARY: In this paper, the traditional uses, phytochemistry and pharmacology of genus Reynoutria were reviewed. As a source of traditional folk medicine, the Reynoutria genus have high medicinal value and they are widely used in medicine. Therefore, we hope our review can help genus Reynoutria get better development and utilization.


Asunto(s)
Fitoterapia , Reynoutria , Etnofarmacología , Medicina Tradicional , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico
8.
Analyst ; 147(21): 4857-4865, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36149381

RESUMEN

Hongmu, a Chinese customary noun representing 29 kinds of wood species such as some Pterocarpus species (abbreviated as spp. hereinafter), Dalbergia spp. and Diospyros spp., is popular among Chinese people due to the furniture made from it. The slow regeneration of hongmu resources led to a decline in production, making hongmu prices high and illegal businesses profit from it. Therefore, it is necessary to identify and distinguish different varieties of hongmu for commercial trade. Herein, a cost-effective and rapid methodology was first developed via atmospheric pressure glow discharge mass spectrometry (APGD-MS) to classify three Dalbergia spp. and three Pterocarpus spp. Meanwhile, principal component analysis (PCA) was further applied to distinguish wood species and six kinds of hongmu extracts were able to be approximately separated into six units. Besides, hongmu could be clearly distinguished from their counterfeits, such as Guibourtia spp., using the method provided here. This method may provide a timely and necessary way for the determination of ingredients and identification of the authenticity of hongmu.


Asunto(s)
Presión Atmosférica , Dalbergia , Humanos , Espectrometría de Masas/métodos , Madera/química , Extractos Vegetales/análisis
9.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36142343

RESUMEN

S-RNase plays vital roles in the process of self-incompatibility (SI) in Rutaceae plants. Data have shown that the rejection phenomenon during self-pollination is due to the degradation of pollen tube RNA by S-RNase. The cytoskeleton microfilaments of pollen tubes are destroyed, and other components cannot extend downwards from the stigma and, ultimately, cannot reach the ovary to complete fertilisation. In this study, four S-RNase gene sequences were identified from the 'XiangShui' lemon genome and ubiquitome. Sequence analysis revealed that the conserved RNase T2 domains within S-RNases in 'XiangShui' lemon are the same as those within other species. Expression pattern analysis revealed that S3-RNase and S4-RNase are specifically expressed in the pistils, and spatiotemporal expression analysis showed that the S3-RNase expression levels in the stigmas, styles and ovaries were significantly higher after self-pollination than after cross-pollination. Subcellular localisation analysis showed that the S1-RNase, S2-RNase, S3-RNase and S4-RNase were found to be expressed in the nucleus according to laser confocal microscopy. In addition, yeast two-hybrid (Y2H) assays showed that S3-RNase interacted with F-box, Bifunctional fucokinase/fucose pyrophosphorylase (FKGP), aspartic proteinase A1, RRP46, pectinesterase/pectinesterase inhibitor 51 (PME51), phospholipid:diacylglycerol acyltransferase 1 (PDAT1), gibberellin receptor GID1B, GDT1-like protein 4, putative invertase inhibitor, tRNA ligase, PAP15, PAE8, TIM14-2, PGIP1 and p24beta2. Moreover, S3-RNase interacted with TOPP4. Therefore, S3-RNase may play an important role in the SI of 'XiangShui' lemon.


Asunto(s)
Proteasas de Ácido Aspártico , Citrus , Autoincompatibilidad en las Plantas con Flores , Citrus/metabolismo , Diacilglicerol O-Acetiltransferasa , Endorribonucleasas , Fucosa , Giberelinas , Fosfolípidos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen/genética , ARN , ARN Ligasa (ATP) , Ribonucleasas/genética , Ribonucleasas/metabolismo , Autoincompatibilidad en las Plantas con Flores/genética , beta-Fructofuranosidasa
10.
Am J Chin Med ; 50(5): 1219-1253, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35681262

RESUMEN

Sinomenium acutum is the dry stem of Sinomenium acutum (Thunb.) Rehd et Wils. (S. acutum) and Sinomenium acutum (Thunb.) Rehd. et Wils. var. cinereum Rehd. et Wils and is mainly distributed in China and Japan. As a traditional Chinese medicine (TCM) for dispelling wind and dampness in China, it is widely distributed and has a long history of drug use. In recent years, with the increase of the incidence of rheumatoid disease, S. acutum has become the focus of research. This paper reviews the literature on the chemical constituents, pharmacological effects, clinical applications and pharmacokinetics and safety of S. acutum from the past 60 years. At present, more than 210 natural compounds have been isolated from S. acutum, including alkaloids, lignans, triterpenoid saponins, steroids, and other structures. Pharmacological activities of S. acutum were mainly reported on anti-inflammatory, analgesic, anti-allergic, immunosuppressive, anti-tumor, liver-protective, anti-oxidative, and other effects, and clinical applications were mainly recorded on rheumatoid arthritis, ankylosing spondylitis, and other diseases. The clinical use of SIN has fewer side effects and more safety; only a small number of gastrointestinal reactions occurred, and the symptoms disappeared after the drug stopped. The purpose of this paper is to lay a foundation and provide reference for the follow-up research and wide application of S. acutum.


Asunto(s)
Alcaloides , Artritis Reumatoide , Botánica , Medicamentos Herbarios Chinos , Alcaloides/uso terapéutico , Antiinflamatorios no Esteroideos , Artritis Reumatoide/tratamiento farmacológico , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Sinomenium/química
11.
Food Chem ; 374: 131793, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-34915370

RESUMEN

The analysis of free fatty acids (FFAs) in edible oils, especially their fine structure, can provide information for nutritional value evaluation and authentication. Here, a strategy based on epoxidation reaction by mCPBA combined with tandem MS was developed to identify and relatively quantify FFAs, including CC location isomers, which can rapidly distinguish different edible oils. Notably, low-abundant FFAs can be detected directly in the presence of high-abundant triacylglycerol (TAG) without complicated pretreatment. We identified a series of CC location isomers via mCPBA-nanoESI-MS/MS, among them, FA 24:1 (Δ13) and FA 24:1 (Δ17) were first identified in edible oils, and the predominant UFAs was FA 18:1 (Δ9), which occupies 98.35% of FA 18:1 in peanut oil while 89.68% in rapeseed oil. The results demonstrated that the proposed method could provide further in-depth CC positional information of oils, promoting the development of structural determination of fatty acids in food chemistry.


Asunto(s)
Ácidos Grasos no Esterificados , Espectrometría de Masas en Tándem , Ácidos Grasos , Aceites de Plantas , Aceite de Brassica napus
12.
Biomed Res Int ; 2021: 9066938, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34540999

RESUMEN

The peroxisome proliferator-activated receptor (PPAR) α/γ-adenosine 5'-monophosphate- (AMP-) activated protein kinase- (AMPK-) sirtuin-1 (SIRT1) pathway and fatty acid metabolism are reported to be involved in influenza A virus (IAV) replication and IAV-pneumonia. Through a cell-based peroxisome proliferator responsive element- (PPRE-) driven luciferase bioassay, we have investigated 145 examples of traditional Chinese medicines (TCMs). Several TCMs, such as Polygonum cuspidatum, Rheum officinale Baillon, and Aloe vera var. Chinensis (Haw.) Berg., were found to possess high activity. We have further detected the anti-IAV activities of emodin (EMO) and its analogs, a group of common important compounds of these TCMs. The results showed that emodin and its several analogs possess excellent anti-IAV activities. The pharmacological tests showed that emodin significantly activated PPARα/γ and AMPK, decreased fatty acid biosynthesis, and increased intracellular ATP levels. Pharmaceutical inhibitors, siRNAs for PPARα/γ and AMPKα1, and exogenous palmitate impaired the inhibition of emodin. The in vivo test also showed that emodin significantly protected mice from IAV infection and pneumonia. Pharmacological inhibitors for PPARα/γ and AMPK signal and exogenous palmitate could partially counteract the effects of emodin in vivo. In conclusion, emodin and its analogs are a group of promising anti-IAV drug precursors, and the pharmacological mechanism of emodin is linked to its ability to regulate the PPARα/γ-AMPK pathway and fatty acid metabolism.


Asunto(s)
Emodina/uso terapéutico , Virus de la Influenza A/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Células A549 , Adenilato Quinasa/efectos de los fármacos , Adenilato Quinasa/metabolismo , Animales , China , Perros , Emodina/análogos & derivados , Emodina/metabolismo , Ácidos Grasos/metabolismo , Humanos , Virus de la Influenza A/patogenicidad , Metabolismo de los Lípidos , Células de Riñón Canino Madin Darby , Medicina Tradicional China/métodos , PPAR alfa/efectos de los fármacos , PPAR alfa/metabolismo , PPAR gamma/efectos de los fármacos , PPAR gamma/metabolismo , Transducción de Señal/efectos de los fármacos , Sirtuina 1/efectos de los fármacos , Sirtuina 1/metabolismo
13.
Am J Chin Med ; 49(7): 1577-1622, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34559620

RESUMEN

Schisandra sphenanthera Rehd. et Wils (S. sphenanthera) is a single species of Schisandra genus, Magnoliaceae family, and it is a famous medicinal herb mostly growing in southern China, China Taiwan and Vietnam. S. sphenanthera is usually used for the treatments of hepatitis, Alzheimer's disease, renal transplantation, osteoporosis, and insomnia. In present studies, approximately 310 natural constituents have been isolated from S. sphenanthera, including lignans, triterpenes, volatile oils, and polysaccharides, which were mainly obtained from the fruits and stems of S. sphenanthera. Pharmocological studies have shown that the extracts and monomeric compounds of S. sphenanthera possessed wide-range bioactivities, such as antitumor, anti-oxidant, anti-inflammatory, osteoblastic, immune regulation, neuroprotective, kidney protection, hepatoprotective, and antiviral activities. However, resource availability, quality control measures, in-depth in vivo pharmacological study, and clinical application are still insufficient and deserve further studies. This review systematically summarized literatures on the botany, phytochemistry, pharmacology, development utilization, and clinical application of S. sphenanthera, in hopes of provide a useful reference for researchers for further studies of this plant.


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Schisandra/química , Humanos , Estructura Molecular
14.
Nat Prod Res ; 35(21): 3888-3894, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32208773

RESUMEN

Two new pregnane alkaloids, (20S)-20α-cinnamoylamino-3ß-dimethylamino-5-en-pregnane (1) and (20S)-20α-cinnamoylamino-3ß-dimethylamino-pregnane (2), and four known alkaloids (+)-(20S)-20-(dimethylamino)-3-(3'R-isopropyl)-lactam-5α-pregn-2-en-4-one (3), axillaridine A (4), pachysamine M (5) and 20α-dimethylamino-16ß-hydroxy-3ß-senecioylamino-pregn-5-ene (6) were obtained from the whole herb of Pachysandra terminalis Sieb. et Zucc. Their structures were determined by various spectral techniques and computed electronic circular dichroism (ECD) data. Compounds 1-4 were tested for cytotoxicity against three human tumor cell lines and a human umbilical vein endothelial cell (HUVEC) line. Compound 4 exhibited moderate cytotoxicity against MCF-7, U251 and A549 cells with IC50 values of 15.01 ± 0.47 µM, 20.13 ± 1.34 µM and 20.04 ± 1.16 µM, respectively; compounds 1-3 showed weak cytotoxic activity against three tumor cells.


Asunto(s)
Alcaloides , Antineoplásicos Fitogénicos/farmacología , Pachysandra , Pregnanos/farmacología , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Humanos , Pachysandra/química , Extractos Vegetales , Pregnanos/aislamiento & purificación
15.
Chin J Nat Med ; 17(10): 778-784, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31703758

RESUMEN

Thibetanosides E-H (1-4), four new steroidal constituents including three rare sulfonates (2-4), were isolated from the roots and rhizomes of Helleborus thibetanus, together with nine known steroidal compounds (5-13). Their structures were elucidated by detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical evidence. In this study, compounds 2-13 were evaluated for their cytotoxic activities against HCT116, A549 and HepG2 tumor cell lines in vitro. Among them, compound 8 (thibetanoside C) showed cytotoxicities against A549 cells(IC50 39.6 ± 1.9 µmol·L-1) and HepG2 cells(IC50 41.5 ± 1.1 µmol·L-1), respectively. Compound 9 (23S, 24S)-24-[(O-ß-D-fucopyranosyl)oxy]-3ß, 23-dihydroxy-spirosta-5, 25(27)-diene-1ß-ylO-(4-O-acetyl- α-L-rhamnopyranosyl)-(1→2)-O-[ß-D-xylopyranosyl-(1→3)]-α-L-arabinopyranoside) showed cytotoxicity against HCT116 cells(IC50 33.6 ± 2.1 µmol·L-1).


Asunto(s)
Citotoxinas/química , Medicamentos Herbarios Chinos/química , Helleborus/química , Esteroides/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citotoxinas/aislamiento & purificación , Citotoxinas/toxicidad , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/toxicidad , Humanos , Estructura Molecular , Raíces de Plantas/química , Esteroides/aislamiento & purificación , Esteroides/farmacología
16.
Chin J Nat Med ; 17(8): 624-630, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31472900

RESUMEN

Five new polyhydroxylated furostanol saponins were isolated from the roots and rhizomes of Tupistra chinensis, and their structures were determined as tupistrosides J-N (1-5), together with four known furostanol saponins (6-9), on the basis of physico-chemical properties and spectral analysis. Among them, compounds 3 and 5 showed cytotoxicity against human cancer cell lines SW620 with IC50 values of 72.5 ± 2.4 and 77.3 ± 2.5 µmol·L-1, respectively. Compound 4 showed cytotoxicity against human cancer cell line HepG2 with IC50 value of 88.6 ± 2.1 µmol·L-1.


Asunto(s)
Antineoplásicos/química , Liliaceae/química , Saponinas/química , Esteroles/química , Células A549 , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Extractos Vegetales/química , Rizoma/química , Saponinas/farmacología , Esteroles/farmacología
17.
Environ Res ; 152: 351-359, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27499130

RESUMEN

This paper proposes a new time-varying coefficient vector autoregressions (VAR) model, in which the coefficient is a linear function of dynamic lagged correlation. The proposed model allows for flexibility in choices of dynamic correlation models (e.g. dynamic conditional correlation generalized autoregressive conditional heteroskedasticity (GARCH) models, Markov-switching GARCH models and multivariate stochastic volatility models), which indicates that it can describe many types of time-varying causal effects. Time-varying causal relations between West Texas Intermediate (WTI) crude oil and the US Standard and Poor's 500 (S&P 500) stock markets are examined by the proposed model. The empirical results show that their causal relations evolve with time and display complex characters. Both positive and negative causal effects of the WTI on the S&P 500 in the subperiods have been found and confirmed by the traditional VAR models. Similar results have been obtained in the causal effects of S&P 500 on WTI. In addition, the proposed model outperforms the traditional VAR model.


Asunto(s)
Modelos Econométricos , Petróleo/economía , Simulación por Computador , Análisis de Regresión
18.
Fitoterapia ; 105: 240-5, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26186990

RESUMEN

Three new steroidal glycosides (1-3) and a novel natural product 4 firstly obtained from a plant source, together with two known steroidal glycosides (5-6) have been isolated from the whole plant of Reineckia carnea. Their structures were determined by physicochemical properties and spectroscopic methods, and their cytotoxic activities against human 1299 tumor cells were evaluated by the MTT method. Compounds 4, 5 and 6 exhibited cytotoxicity with IC50 values of 50.3 µmol·L(-1), 67.2 µmol·L(-1) and 61.8 µmol·L(-1), while compounds 1, 2, and 3 showed no cytotoxicity with the cells.


Asunto(s)
Glicósidos/química , Liliaceae/química , Raíces de Plantas/química , Esteroides/química , Línea Celular Tumoral , Glicósidos/aislamiento & purificación , Humanos , Estructura Molecular , Esteroides/aislamiento & purificación
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