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1.
Planta Med ; 89(5): 484-492, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35789994

RESUMEN

To find inhibitors against skeletal muscle loss, we isolated a lignan compound ((-)-(2R,3R-1,4-O-diferuloylsecoisolarciresinol, DFS) from the stem of Alnus japonica. C2C12 myoblasts were treated with DFS during differentiation. To induce an in vitro atrophic condition, differentiated myotubes were treated with dexamethasone (a synthetic glucocorticoid). DFS (10 nM) increased expression levels of myogenic factors and the number of multi-nucleated myotubes expressing myosin heavy chain (MHC). The myogenic potential of DFS could be attributed to p38 MAPK activation. DFS also protected against dexamethasone-induced damage, showing increased expression of MHC and mammalian target of rapamycin (mTOR), a major anabolic factor. Under atrophic condition, the anti-myopathy effect of DFS was associated with inactivation of NF-κB signaling pathway and the subsequent suppression of muscle degradative E3 ligases and myostatin. DFS treatment also restored fast muscle fiber (type II a, II b, and II x), known to be susceptible to dexamethasone. These results indicate that DFS isolated from A. japonica can stimulate myogenesis via p38 MAPK activation and alleviate muscle atrophy by modulating the expression of genes associated with muscle protein anabolism/catabolism. Thus, we propose that DFS can be used as a pharmacological and nutraceutical agent for increasing muscle strength or protecting muscle loss.


Asunto(s)
Alnus , Lignanos , Alnus/metabolismo , Lignanos/farmacología , Músculo Esquelético/metabolismo , Atrofia Muscular/inducido químicamente , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Fibras Musculares Esqueléticas , Dexametasona/efectos adversos , Desarrollo de Músculos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/uso terapéutico
2.
J Microbiol Biotechnol ; 30(5): 749-752, 2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32482941

RESUMEN

In the search for novel, natural melanogenesis inhibitors, a new sesquiterpene, inularin, was isolated from the flowers of Inula britannica, and the structure was determined using spectroscopic and chemical methods. The antimelanogenic effects of inularin on B16F10 melanoma cells and zebrafish embryos were evaluated. Inularin dose-dependently reduced melanocyte-stimulating hormone-induced melanin production and L-DOPA oxidation in B16F10 cells. Zebrafish embryos were used to confirm the antimelanogenic activity. Inularin significantly decreased the pigmentation of embryos compared with untreated controls.


Asunto(s)
Flores/química , Inula/química , Melaninas/metabolismo , Sesquiterpenos , Animales , Línea Celular Tumoral , Embrión no Mamífero/efectos de los fármacos , Melaninas/análisis , Melanoma/metabolismo , Ratones , Pigmentación/efectos de los fármacos , Sesquiterpenos/química , Sesquiterpenos/farmacología , Pez Cebra
3.
Molecules ; 25(10)2020 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-32429421

RESUMEN

Pancreatic cancer has a high mortality rate due to poor rates of early diagnosis. One tumor suppressor gene in particular, p53, is frequently mutated in pancreatic cancer, and mutations in p53 can inactivate normal wild type p53 activity and increase expression of transcription factor forkhead box M1 (FoxM1). Overexpression of FoxM1 accelerates cellular proliferation and cancer progression. Therefore, inhibition of FoxM1 represents a therapeutic strategy for treating pancreatic cancer. Broussoflavonol B (BF-B), isolated from the stem bark of Broussonetia kazinoki Siebold has previously been shown to inhibit the growth of breast cancer cells. This study aimed to investigate whether BF-B exhibits anti-pancreatic cancer activity and if so, identify the underlying mechanism. BF-B reduced cell proliferation, induced cell cycle arrest, and inhibited cell migration and invasion of human pancreatic cancer PANC-1 cells (p53 mutated). Interestingly, BF-B down-regulated FoxM1 expression at both the mRNA and protein level. It also suppressed the expression of FoxM1 downstream target genes, such as cyclin D1, cyclin B1, and survivin. Cell cycle analysis showed that BF-B induced the arrest of G0/G1 phase. BF-B reduced the phosphorylation of extracellular signal-regulated kinase ½ (ERK½) and expression of ERK½ downstream effector c-Myc, which regulates cell proliferation. Furthermore, BF-B inhibited cell migration and invasion, which are downstream functional properties of FoxM1. These results suggested that BF-B could repress pancreatic cancer cell proliferation by inactivation of the ERK/c-Myc/FoxM1 signaling pathway. Broussoflavonol B from Broussonetia kazinoki Siebold may represent a novel chemo-therapeutic agent for pancreatic cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Broussonetia/química , Flavonoles/farmacología , Proteína Forkhead Box M1/genética , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ciclina B1/genética , Ciclina B1/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Cámaras de Difusión de Cultivos , Flavonoles/aislamiento & purificación , Proteína Forkhead Box M1/antagonistas & inhibidores , Proteína Forkhead Box M1/metabolismo , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Humanos , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Páncreas/metabolismo , Páncreas/patología , Corteza de la Planta/química , Extractos Vegetales/química , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal , Survivin/genética , Survivin/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
4.
Molecules ; 25(3)2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-32041324

RESUMEN

Aberrant activation of a Wnt/ß-catenin pathway results in nuclear accumulation of ß-catenin in colon cancer. Inhibiting ß-catenin is one strategy for treating colon cancer. Here, we identified Z-ajoene, a sulfur containing compound isolated from crushed garlic, as an inhibitor of colon cancer cell growth. Z-Ajoene repressed ß-catenin response transcriptional activity, intracellular ß-catenin levels, and its representative target protein levels (c-Myc and cyclin D1) in SW480 colon cancer cells. To clarify the regulatory mechanism of decreased ß-catenin levels, we examined the effect of Z-ajoene on ß-catenin phosphorylation, which is involved in ß-catenin degradation. Z-Ajoene promoted the phosphorylation of ß-catenin at Ser45 in a casein kinase 1α (CK1α)-dependent manner, which is an essential step in ß-catenin degradation in the cytosol. These findings indicate that Z-ajoene from garlic may be a potential chemotherapeutic agent by modulating CK1α activity and the Wnt/ß-catenin signaling pathway.


Asunto(s)
Antineoplásicos/farmacología , Caseína Quinasa Ialfa/metabolismo , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Disulfuros/farmacología , Fosforilación/efectos de los fármacos , beta Catenina/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Ciclina D1/metabolismo , Ajo/química , Células HEK293 , Humanos , Sulfóxidos , Vía de Señalización Wnt/efectos de los fármacos
5.
J Agric Food Chem ; 66(8): 1935-1940, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29433311

RESUMEN

A sensitive and specific high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS) method combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of grayanotoxins I and III in dietary supplements and homemade wine. Grayanotoxins I and III were successfully extracted using solid-phase extraction cartridges, characterized by LC-QTOF-MS, and quantitated by LC-MS/MS. The LC-MS/MS calibration curves were linear over concentrations of 10-100 ng/mL (grayanotoxin I) and 20-400 ng/mL (grayanotoxin III). Grayanotoxins I and III were found in 51 foodstuffs, with quantitative determinations revealing total toxin concentrations of 18.4-101 000 ng/mL (grayanotoxin I) and 15.3-56 000 ng/mL (grayanotoxin III). The potential of the validated method was demonstrated by successful quantitative analysis of grayanotoxins I and III in dietary supplements and homemade wine; the method appears suitable for the routine detection of grayanotoxins I and III from Rhododendron brachycarpum.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Diterpenos/análisis , Rhododendron/química , Espectrometría de Masas en Tándem/métodos , Vino/análisis , Contaminación de Alimentos/análisis , Extracción en Fase Sólida
6.
Bioorg Med Chem Lett ; 27(6): 1401-1404, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28228365

RESUMEN

To overcome the muscle atrophy, such as cachexia and sarcopenia, we tried to find myogenic agents from medicinal plants. From myogenic extract of Coptis japonica, we purified six isoquinoline alkaloids and evaluated their effects on transactivation of myoD and MHC expression in C2C12 cells during differentiation process. Among obtained compounds, magnoflorine most efficiently enhanced the myoblast differentiation by activating the p38 MAP kinase and Akt pathway, and also increased the number of multinucleated and cylinder-shaped myotubes. These results propose that magnoflorine from Coptis japonica might be a promising lead compound for the development of anti-muscle atrophy drug.


Asunto(s)
Alcaloides/farmacología , Diferenciación Celular/efectos de los fármacos , Coptis/química , Mioblastos/efectos de los fármacos , Animales , Línea Celular , Ratones , Mioblastos/citología
7.
J Chromatogr Sci ; 55(3): 214-221, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28115391

RESUMEN

The purpose of this study is to develop LC-MS-MS and LC-Q-Orbitrap/MS method for the analysis of the components of Pueraria mirifica, which are illegal additives in dietary supplements. Blank samples and samples spiked with miroestrol and isomiroestrol were used for the initial development and validation studies. Specificity, linearity, limit of quantification (LOQ), limit of detection (LOD), accuracy, precision, recovery and stability were employed as the validation parameters. The LODs of miroestrol and isomiroestrol were found to be 4.17 and 0.84 ng/mL, respectively, whereas their LOQs were 12.50 and 2.52 ng/mL, respectively. The determination coefficient was over 0.999, intra- and inter-day precisions were 0.8-6.9 and 1.9-9.8%, respectively, and intra and inter-day accuracies were 82.1-103.7 and 85.0-109.7%, respectively. The mean recoveries of the targeted compounds from the dietary supplements ranged from 86.9 to 108.9%. The relative standard deviations (RSDs) for recovery were <5.8%. On the other hand, the RSD of stability was <11.0%. Eight dietary supplements were tested using the newly developed and validated method, out of which six were found to be adulterated samples.


Asunto(s)
Cromatografía Liquida/métodos , Suplementos Dietéticos/análisis , Extractos Vegetales/química , Pueraria/química , Esteroides/análisis , Espectrometría de Masas en Tándem/métodos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
8.
Artículo en Inglés | MEDLINE | ID: mdl-27167568

RESUMEN

A new tadalafil analogue was found, along with nortadalafil, using HPLC-DAD during the inspection of a health product sold without official approval. The analogue was separated using a semi-preparative HPLC system and its structure was determined by a combination of mass spectrometry and NMR spectroscopy. The compound was identified as a tadalafil analogue in which the N-methyl group of tadalafil was replaced with a tadalafil precursor moiety. Nuclear Overhauser effect spectroscopy experiments suggested a cis-relationship between the substituents on a piperidine ring in the tadalafil moiety.


Asunto(s)
Suplementos Dietéticos/análisis , Tadalafilo/análogos & derivados , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masas/métodos , Estructura Molecular , Inhibidores de Fosfodiesterasa 5
9.
Fitoterapia ; 112: 90-6, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27223849

RESUMEN

In this study, we evaluated the insulin-sensitizing effect of flavans purified from Broussonetia kazinoki Siebold (BK) on 3T3-L1 adipocytes. Among the tested compounds, kazinol B enhanced intracellular lipid accumulation, gene expression of proliferator-activated receptorγ (PPARγ) and CCAAT/enhancer binding protein-alpha (C/EBPα), and consistently induced PPARγ transcriptional activation. To further investigate the insulin-sensitizing effect of kazinol B, we measured glucose analogue uptake by fully differentiated adipocytes and myotubes. Kazinol B increased 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose (2-NBDG) uptake by cells by upregulating the gene expression and translocation of glucose transporter 4 (GLUT-4) into the plasma membrane in adipocytes. Kazinol B stimulated the gene expression and secretion of adiponectin, which is associated with a low risk of types 1 and 2 diabetes mellitus. We also suggested the mechanism of the antidiabetic effect of kazinol B by assaying Akt and AMP-activated protein kinase (AMPK) phosphorylation. In conclusion, kazinol B isolated from BK improved insulin sensitivity by enhancing glucose uptake via the insulin-Akt signaling pathway and AMPK activation. These results suggest that kazinol B might be a therapeutic candidate for diabetes mellitus.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Broussonetia/química , Flavonoides/farmacología , Resistencia a la Insulina , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células 3T3-L1 , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , 4-Cloro-7-nitrobenzofurazano/metabolismo , Adipocitos/efectos de los fármacos , Adiponectina/metabolismo , Animales , Desoxiglucosa/análogos & derivados , Desoxiglucosa/metabolismo , Glucosa/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Hipoglucemiantes/farmacología , Ratones , PPAR gamma/metabolismo , Fosforilación , Transducción de Señal/efectos de los fármacos
10.
J Sci Food Agric ; 96(4): 1085-92, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25800973

RESUMEN

BACKGROUND: Salicornia herbacea L. is a halophyte that grows in salt marshes and contains significant amounts of salts and minerals. Because it is known as a folk medication to treat diseases, various processed products such as powder, globular type of powder, laver and extract have been developed. However, it is difficult to process as a drink because of its high salinity. In the present study, glasswort vinegar (GV) containing high amounts of organic acids and minerals was developed via two-step fermentation with unpolished rice substrates and investigated its antioxidant and anti-fatigue activities. RESULTS: GV showed various free radical scavenging effects, reducing power, oxidized-LDL inhibition and superoxide dismutase-like activities. Compared with the control group (orally administered 7 g kg(-1) distilled water), the GV supplementation group showed increased running endurance and had higher glycogen accumulation in liver and muscles of rats exhausted by exercise. Furthermore, the GV-administered group demonstrated significantly elevated lactate and ATP metabolism, promoting enzyme activities such as muscle creatine kinase and lactate dehydrogenase, whereas serum fatigue biomarkers such as ammonia, lactate and inorganic acid were markedly decreased. CONCLUSION: These results indicate that GV can be used as a functional food for the development of a dietary beverage to alleviate fatigue.


Asunto(s)
Chenopodiaceae , Fatiga/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Ácido Acético/farmacología , Ácido Acético/uso terapéutico , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Modelos Animales de Enfermedad , Tolerancia al Ejercicio/efectos de los fármacos , Masculino , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley
11.
Artículo en Inglés | MEDLINE | ID: mdl-25263347

RESUMEN

A number of 188 food and dietary supplement samples were collected from 2009 to the first half of 2013 in Korean online and offline stores. A method to identify phosphodiesterase-5 (PDE-5) inhibitors and their analogues using liquid chromatography-electrospray ionisation-mass spectrometry/mass spectrometry (LC-ESI-MS/MS) was validated. Limit of detection and limit of quantitation of liquid-type and solid-type negative samples ranged from 0.05 to 3.33 ng/mL or ng/g and from 0.15 to 10.00 ng/mL or ng/g, respectively. Recoveries ranged from 83% to 112%. Nineteen PDE-5 inhibitors and their analogues were detected, with tadalafil group compounds being the most frequently observed (53.0%), followed by the sildenafil group (42.5%). Tadalafil concentrations ranged from 0.08 to 138.69 mg/g. Compounds were most frequently detected in capsules (in 40 of 80 adulterated samples). To protect public health and food safety, appropriate monitoring of PDE-5 inhibitors and their analogues in foods and dietary supplements is recommended.


Asunto(s)
Cromatografía Liquida/métodos , Suplementos Dietéticos/análisis , Análisis de los Alimentos/métodos , Inhibidores de Fosfodiesterasa 5/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Contaminación de Alimentos , Humanos , Límite de Detección , República de Corea
12.
Phytother Res ; 29(10): 1605-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26449499

RESUMEN

Oxidative stress promotes several diseases, including liver disease. We have isolated several stilbenoids from Rheum undulatum to investigate their hepatoprotective activities and mechanism. Stilbenoids from R. undulatum protects hepatocytes against arachidonic acid + iron (AA + Fe) induced oxidative stress. Pterostilbene (compound 5) shows stronger activity than the others. Trimethoxystilbenoid (compound 6) shows best activity on protection of HepG2 cells from AA + Fe-induced oxidative stress, and trans-stilbenoid (compound 7) shows weak activity. These stilbenoids suppress ROS generation in AA + Fe-treated HepG2 cells and also suppress AA + Fe-induced MMP disruption. Their protective effects on AA + Fe-induced MMP disruption were abrogated by treatment of AMP-activated protein kinase (AMPK) inhibitor, compound C or transfection of dominant negative form of AMPK. Taken together, stilbenoids from R. undulatum protect hepatocytes against AA + Fe-induced oxidative stress through AMPK activation. And the methoxy groups in the aryl groups are important for their cytoprotective activity.


Asunto(s)
Hepatocitos/efectos de los fármacos , Estrés Oxidativo , Rheum , Estilbenos/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Ácido Araquidónico/metabolismo , Células Hep G2 , Humanos , Estrés Oxidativo/efectos de los fármacos , Fosforilación , Sustancias Protectoras/farmacología
13.
Food Chem Toxicol ; 50(6): 2042-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22504089

RESUMEN

Yellow onion (Allium cepa) extract showed enhanced antioxidative effects in 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC) and 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate and acetyl ester (CM-H(2)DCFDA) assay after being treated with a crude enzyme extract from soybean paste fungi, Aspergillus kawachii. HPLC analysis showed two increased and two decreased peaks after enzyme treatment. The decreased peaks were identified as quercetin-3,4'-di-O-ß-d-glucoside (1) and quercetin-4'-O-ß-d-glucoside (2), and peaks that increased were quercetin-3-O-ß-d-glucoside (3) and quercetin (4), respectively. It was expected that 3 and 4 were originated from the glucosidic cleavage of their glucosides, 1 and 2. Among the increased compounds, only quercetin (4) showed strong antioxidative activity in the DPPH assay. In addition, the protective effect against glutamate-induced neurotoxicity in HT22 cells was increased when treated with 25 µg/ml of fermented onion. The enhanced neuroprotective effect was also originated from the increased quercetin content. As a consequence, fermentation raised the quercetin content in onion, and subsequently increased the antioxidative and neuroprotective activities.


Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Cebollas/química , Quercetina/química , Animales , Aspergillus/metabolismo , Bacterias/metabolismo , Compuestos de Bifenilo/química , Línea Celular , Cromatografía Líquida de Alta Presión , Fermentación , Flavonas/análisis , Manipulación de Alimentos , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Hipocampo/citología , Ratones , Fármacos Neuroprotectores/farmacología , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Solventes
14.
Mol Pharmacol ; 69(6): 1783-90, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16510559

RESUMEN

In the course of screening inhibitors of matrix metalloproteinase (MMP)-9 induction in macrophages, we isolated decursin, a coumarin compound, from the roots of Angelicae gigas. As a marker for the screening and isolation, we tested expression of MMP-9 in RAW264.7 cells and THP-1 cells after treatment with bacterial lipopolysaccharide (LPS), the TLR-4 ligand. Decursin suppressed MMP-9 expression in cells stimulated by LPS in a dose-dependent manner at concentrations below 60 microM with no sign of cytotoxicity. The suppressive effect of decursin was observed not only in cells stimulated with ligands for TLR4, TLR2, TLR3, and TLR9 but also in cells stimulated with interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha, indicating that the molecular target of decursin is common signaling molecules induced by these stimulants. In addition to the suppression of MMP-9 expression, decursin blocked nitric oxide production and cytokine (IL-8, MCP-1, IL-1beta, and TNF-alpha) secretion induced by LPS. To find out the molecular mechanism responsible for the suppressive effect of decursin, we analyzed signaling molecules involved in the TLR-mediated activation of MMP-9 and cytokines. Decursin blocked phosphorylation of IkappaB and nuclear translocation of NF-kappaB in THP-1 cells activated with LPS. Furthermore, expression of a luciferase reporter gene under the promoter containing NF-kappaB binding sites was blocked by decursin. These data indicate that decursin is a novel inhibitor of NF-kappaB activation in signaling induced by TLR ligands and cytokines.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Benzopiranos/farmacología , Butiratos/farmacología , Citocinas/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Inhibidores de la Metaloproteinasa de la Matriz , FN-kappa B/antagonistas & inhibidores , Animales , Antiinflamatorios no Esteroideos/análisis , Benzopiranos/análisis , Butiratos/análisis , Humanos , Ligandos , Macrófagos/metabolismo , Ratones , FN-kappa B/aislamiento & purificación , Fosforilación/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Receptores Toll-Like/agonistas
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