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2.
J Nat Med ; 76(4): 803-810, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35691991

RESUMEN

S-Alk(en)ylcysteine sulfoxides (CSOs), such as methiin, alliin, and isoalliin, are health-beneficial natural products biosynthesized in the genus Allium. Here, we report the induction of multiple callus tissue lines from three Allium vegetables, onion (A. cepa), Welsh onion (A. fistulosum), and Chinese chive (A. tuberosum), and their ability to accumulate CSOs. Callus tissues were initiated and maintained in the presence of picloram and 2-isopentenyladenine as auxin and cytokinin, respectively. For all plant species tested, the callus tissues almost exclusively accumulated methiin as CSO, while the intact plants contained a substantial amount of isoalliin together with methiin. These results suggest that the cellular developmental conditions and the regulatory mechanisms required for the biosynthesis of methiin are different from those of alliin and isoalliin. The methiin content in the callus tissues of onion and Welsh onion was much higher compared to that in the intact plants, and its cellular concentration could be estimated as 1.9-21.7 mM. The activity of alliinase that degrades CSOs in the callus tissues was much lower than that of the intact plants for onion and Welsh onion, but at similar levels as in the intact plants for Chinese chive. Our findings that the callus tissues of onion and Welsh onion showed high methiin content and low alliinase activity highlighted their potential as a plant-based system for methiin production.


Asunto(s)
Allium , Productos Biológicos , Cebollas/metabolismo , Sulfóxidos
3.
Chem Pharm Bull (Tokyo) ; 67(6): 534-539, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31155558

RESUMEN

One triterpene and five triterpene glycosides, including four new compounds, have been identified in the underground parts of Glycyrrhiza bucharica, which was shown to be closely related to Glycyrrhizin-producing Glycyrrhiza species, G. uralensis, G. glabra and G. inflata, based on their chloroplast rbcL sequences. Two known compounds were identified squasapogenol and macedonoside C. The structures of four new compounds, bucharosides A, B, C, and D, were determined to be 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucuronopyranosyl-(1→2)-ß-D-glucuronopyranosyl-22-O-α-L-rhamnopyranosyl squasapogenol, 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucuronopyranosyl-(1→2)-ß-D-glucuronopyranosyl-macedonic acid, 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucuronopyranosyl-(1→2)-ß-D-glucuronopyranosyl-squasapogenol, and 22-O-α-L-rhamnopyranosyl squasapogenol, respectively. Contents of these triterpene glycosides were less than 0.5% of dry weight, and no main saponin, like glycyrrhizin or macedonoside C found in other Glycyrrhiza species, was found in the underground parts of G. bucharica.


Asunto(s)
Glycyrrhiza/química , Extractos Vegetales/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Glycyrrhiza/metabolismo , Espectroscopía de Resonancia Magnética , Conformación Molecular , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Tayikistán , Terpenos/química , Terpenos/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificación
4.
J Leukoc Biol ; 96(6): 1087-100, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25210146

RESUMEN

Inflammasome activation initiates the development of many inflammatory diseases, including obesity and type 2 diabetes. Therefore, agents that target discrete activation steps could represent very important drugs. We reported previously that ILG, a chalcone from Glycyrrhiza uralensis, inhibits LPS-induced NF-κB activation. Here, we show that ILG potently inhibits the activation of NLRP3 inflammasome, and the effect is independent of its inhibitory potency on TLR4. The inhibitory effect of ILG was stronger than that of parthenolide, a known inhibitor of the NLRP3 inflammasome. GL, a triterpenoid from G. uralensis, had similar inhibitory effects on NLRP3 activity, but high concentrations of GL were required. In contrast, activation of the AIM2 inflammasome was inhibited by GL but not by ILG. Moreover, GL inhibited NLRP3- and AIM2-activated ASC oligomerization, whereas ILG inhibited NLRP3-activated ASC oligomerization. Low concentrations of ILG were highly effective in IAPP-induced IL-1ß production compared with the sulfonylurea drug glyburide. In vivo analyses revealed that ILG potently attenuated HFD-induced obesity, hypercholesterolemia, and insulin resistance. Furthermore, ILG treatment improved HFD-induced macrovesicular steatosis in the liver. Finally, ILG markedly inhibited diet-induced adipose tissue inflammation and IL-1ß and caspase-1 production in white adipose tissue in ex vivo culture. These results suggest that ILG is a potential drug target for treatment of NLRP3 inflammasome-associated inflammatory diseases.


Asunto(s)
Antiinflamatorios/uso terapéutico , Proteínas Portadoras/antagonistas & inhibidores , Chalconas/uso terapéutico , Dieta Alta en Grasa/efectos adversos , Glycyrrhiza uralensis/química , Inflamasomas/efectos de los fármacos , Inflamación/prevención & control , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/patología , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Línea Celular Tumoral , Chalconas/aislamiento & purificación , Chalconas/farmacología , Proteínas de Unión al ADN/metabolismo , Gliburida/farmacología , Gliburida/uso terapéutico , Ácido Glicirrínico/farmacología , Ácido Glicirrínico/uso terapéutico , Humanos , Hipercolesterolemia/tratamiento farmacológico , Resistencia a la Insulina , Interleucina-1beta/biosíntesis , Polipéptido Amiloide de los Islotes Pancreáticos/antagonistas & inhibidores , Polipéptido Amiloide de los Islotes Pancreáticos/farmacología , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR , Obesidad/tratamiento farmacológico , Obesidad/prevención & control , Organismos Libres de Patógenos Específicos
5.
Biol Pharm Bull ; 35(9): 1447-53, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22975494

RESUMEN

Diabetic retinopathy is a common complication of diabetes mellitus (DM). The oxidative damage inflicted on retinal pigment epithelial (RPE) cells by high glucose closely approximates the molecular basis for the loss of vision associated with this disease. We investigate a novel algae-derived polysaccharide compound for its role in protecting ARPE-19 cells from high glucose-induced oxidative damage. ARPE-19 cells were cultured for 4 d with normal concentration of D-glucose, and exposed to either normal or high concentrations of D-glucose in the presence or absence of the polysaccharide compound at variety of concentrations for another 48 h. Taurine was used as a positive control. Activity of super oxide dismutase (SOD) and concentration of glutathione (GSH) were measured as well as cytotoxicity of high glucose and the polysaccharide compound. To analyse cellular damage by high glucose, activation of Annexin V and p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) were examined. Our results showed that a significant cellular damage on ARPE-19 cells after 48 h treatment with high glucose, accompanied by a decrease in SOD activity and GSH concentration; high glucose also caused ARPE-19 cell apoptosis and activation of p38MAPK and ERK. As the non-toxic polysaccharide compound protected ARPE-19 cells from high glucose-induced cellular damage, the compound recovered SOD activity and concentration of GSH in the cells. The compound also abrogated the cell apoptosis and activation of p38MAPK and ERK. Therefore, the polysaccharide compound derived from algae extracts could be unique candidate for a new class of anti-DM and anti-oxidative damage.


Asunto(s)
Antioxidantes/farmacología , Retinopatía Diabética/metabolismo , Glucosa/efectos adversos , Estrés Oxidativo/efectos de los fármacos , Phaeophyceae/química , Polisacáridos/farmacología , Epitelio Pigmentado de la Retina/efectos de los fármacos , Antioxidantes/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular , Retinopatía Diabética/inducido químicamente , Activación Enzimática/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Glutatión/metabolismo , Humanos , Fitoterapia , Extractos Vegetales/farmacología , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/metabolismo , Superóxido Dismutasa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
6.
Phytochemistry ; 68(21): 2670-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17643455

RESUMEN

Hyperforin is a pharmacologically active constituent of Hypericum perforatum (St. John's wort). In vitro cultures of this medicinal plant were found to contain hyperforin and three related polyprenylated acylphloroglucinol derivatives. The accumulation of these compounds was coupled to shoot regeneration, with secohyperforin being the major constituent in morphogenic cultures. The structure of secohyperforin was elucidated online by LC-DAD, -MS, and -NMR. In multiple shoot cultures, the ratio of hyperforin to secohyperforin was strongly influenced by the phytohormones N6-benzylaminopurine (BAP) and naphthalene-1-acetic acid (NAA). While increasing concentrations of BAP stimulated the formation of hyperforin, increasing concentrations of NAA elevated the level of secohyperforin. No differential stimulation was observed after elicitor treatment. Hyperforin and secohyperforin are proposed to arise from a branch point in the biosynthetic pathway.


Asunto(s)
Hypericum/química , Floroglucinol/análogos & derivados , Terpenos/química , Compuestos Bicíclicos con Puentes/química , Células Cultivadas , Cromatografía de Gases y Espectrometría de Masas , Hypericum/metabolismo , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/química , Floroglucinol/metabolismo , Componentes Aéreos de las Plantas , Extractos Vegetales/química , Terpenos/metabolismo , Técnicas de Cultivo de Tejidos
7.
J Asian Nat Prod Res ; 6(4): 259-64, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15621584

RESUMEN

Four novel cycloartanes, named sphaerophysone A (1), B (2), C (3) and D (4), were isolated from the ethanol extract of Sphaerophysa salsula (Pall.) DC. The structures were elucidated on the basis of spectral evidence, and the stereochemistry of compound 1 was defined by X-ray crystallographic analysis. Sphaerophysone B (2) may be an artifact formed in the isolation procedure.


Asunto(s)
Fabaceae/química , Triterpenos/química , Medicamentos Herbarios Chinos , Conformación Molecular , Estructura Molecular , Triterpenos/aislamiento & purificación
8.
J Asian Nat Prod Res ; 6(4): 265-9, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15621585

RESUMEN

A new compound, sphaerophysin A (1), together with 16 known compounds (2-17) were obtained from the ethanolic extract of the seeds of Sphaerophysa salsula. The structure of 1 was elucidated on the basis of spectral and chemical evidence. Compounds 2-17 were isolated from the plant for the first time.


Asunto(s)
Fabaceae/química , Lignanos/química , Semillas/química , Medicamentos Herbarios Chinos , Lignanos/aislamiento & purificación , Espectroscopía de Resonancia Magnética
9.
J Biol Chem ; 279(43): 44613-20, 2004 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-15310761

RESUMEN

The pentaketide 1,3,6,8-tetrahydroxynaphthalene (T4HN) is a key precursor of 1,8-dihydroxynaphthalene-melanin, an important virulence factor in pathogenic fungi, where T4HN is believed to be the direct product of pentaketide synthases. We showed recently the involvement of a novel protein, Ayg1p, in the formation of T4HN from the heptaketide precursor YWA1 in Aspergillus fumigatus. To investigate the mechanism of its enzymatic function, Ayg1p was purified from an Aspergillus oryzae strain that overexpressed the ayg1 gene. The Ayg1p converted the naphthopyrone YWA1 to T4HN with a release of the acetoacetic acid. Although Ayg1p does not show significant homology with known enzymes, a serine protease-type hydrolytic motif is present in its sequence, and serine-specific inhibitors strongly inhibited the activity. To identify its catalytic residues, site-directed Ayg1p mutants were expressed in Escherichia coli, and their enzyme activities were examined. The single substitution mutations S257A, D352A, and H380A resulted in a complete loss of enzyme activity in Ayg1p. These results indicated that the catalytic triad Asp352-His380-Ser257 constituted the active-site of Ayg1p. From a Dixon plot analysis, 2-acetyl-1,3,6,8-tetrahydroxynaphthalene was found to be a strong mixed-type inhibitor, suggesting the involvement of an acyl-enzyme intermediate. These studies support the mechanism in which the Ser257 at the active site functions as a nucleophile to attack the YWA1 side-chain 1'-carbonyl and cleave the carbon-carbon bond between the naphthalene ring and the side chain. Acetoacetic acid is subsequently released from the Ser257-O-acetoacetylated Ayg1p by hydrolysis. An enzyme with activity similar to Ayg1p in melanin biosynthesis has not been reported in any other organism.


Asunto(s)
Aspergillus oryzae/metabolismo , Liasas de Carbono-Carbono/genética , Liasas de Carbono-Carbono/fisiología , Regulación Fúngica de la Expresión Génica , Melaninas/biosíntesis , Melaninas/genética , Acetoacetatos/química , Acetoacetatos/metabolismo , Secuencias de Aminoácidos , Ácido Aspártico/química , Aspergillus fumigatus/metabolismo , Aspergillus oryzae/genética , Sitios de Unión , Carbono/química , Catálisis , Dominio Catalítico , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Genes Fúngicos/genética , Histidina/química , Hidrólisis , Cinética , Espectrometría de Masas , Melaninas/química , Modelos Químicos , Complejos Multienzimáticos , Mutagénesis Sitio-Dirigida , Mutación , Naftoles/química , Plásmidos/metabolismo , Pironas/metabolismo , Serina/química , Especificidad por Sustrato
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