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1.
Biosci Biotechnol Biochem ; 87(12): 1514-1522, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37667527

RESUMEN

Although herbs and spices have been used in traditional medicine for more than a century owing to their health benefits, the associated underlying mechanism is still not clear. Since the G protein-coupled receptor 35 (GPR35) has been linked to exert various antioxidant and anti-inflammatory effects, we screened 19 different herbs and spices for possible GPR35 agonist(s) to understand the GPR35-dependent functions of herbs and spices. Among the screened extracts, the ethyl acetate extract of thyme exhibited a remarkable GPR35 agonistic activity. Activity-guided separations allowed us to identify 2 polyphenolic phytochemicals, eriodictyol and thymonin, acting as GPR35 agonists. Both eriodictyol and thymonin showed a potent and specific agonist activity toward GPR35 with half maximal effective concentration values of 5.48 and 8.41 µm, respectively. These findings indicate that these phytochemicals may have beneficial health effects upon GPR35 activation.


Asunto(s)
Flavanonas , Flavanonas/farmacología , Especias , Antioxidantes , Receptores Acoplados a Proteínas G
2.
J Nat Prod ; 86(8): 1960-1967, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37530540

RESUMEN

The roots of Fibraurea recisa are recognized as a rich source of protoberberine and aporphine alkaloids, but the non-alkaloidal metabolites in this plant are underexplored. The present study investigated the chemical composition of the plant roots using untargeted metabolomics-based molecular networking and MS2LDA motif annotation, revealing the presence of a characteristic fragment motif related to several sinapoyl-functionalized metabolites. Guided by the targeted motif, two new sinapic acid-ecdysteroid hybrids, named 3-O-sinapoyl makisterone A (1) and 2-O-sinapoyl makisterone A (2), were isolated. The structures of these compounds, including their absolute configuration, were elucidated by HR-ESIQTOFMS, MS2 fragmentation, NMR spectroscopy, and chemical degradation coupled with optical rotation measurements. Although neither compound inhibited nitric oxide (NO) production or inducible nitric oxide synthase (iNOS) protein expression on lipopolysaccharide-induced RAW 264 cells, 2 significantly suppressed cyclooxygenase 2 (COX-2) protein expression at 1-30 µM. Additionally, decreased expression of COX-2 protein was barely observed after treatment with methyl sinapate or makisterone A, the steroid skeleton of 1 and 2. These results indicated that the presence of the sinapoyl moiety at C-2 on the C28-ecdysteroid skeleton played a key role in the selectivity for the suppression of the COX-2 protein expression.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2 , Ecdisteroides , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Ecdisteroides/farmacología , Ésteres , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico , Lipopolisacáridos/farmacología
3.
Food Chem (Oxf) ; 5: 100123, 2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-35898333

RESUMEN

Obesity is now recognized as an epidemic, requiring rapid intervention. We previously demonstrated that vanilloids from the African spice known as Grains of Paradise (GOP) exhibit strong anti-obesity effects. Here, the molecular mechanism behind the obesity prevention property of the GOP extract was investigated by employing molecular networking-based lipid profiling and 16S rRNA sequencing. Administration of either GOP extract or two of its components, 6-paradol and 6-gingerol, reversed the unbalanced gut microbiota composition induced by a high-fat diet (HFD) with a decrease in Firmicutes / Bacteroidetes ratio and increase in genera Bifidobacterium and Akkermansia. Moreover, GOP extract ameliorated abnormal fatty acid metabolism in gut bacteria. Furthermore, lipid molecular networking revealed differences in lipid composition, such as triglycerides and bile acids, in the feces. These results suggest that 6-paradol and 6-gingerol can restore an unhealthy gut environment and prevent lipid absorption, a possible consequence of the reconstruction of the gut microbiota.

4.
Front Plant Sci ; 12: 660303, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149757

RESUMEN

Iron (Fe) excess is a major constraint on crop production in flooded acidic soils, particularly in rice cultivation. Under Fe excess, plants activate a complex mechanism and network regulating Fe exclusion by roots and isolation in various tissues. In rice, the transcription factors and cis-regulatory elements (CREs) that regulate Fe excess response mechanisms remain largely elusive. We previously reported comprehensive microarray analyses of several rice tissues in response to various levels of Fe excess stress. In this study, we further explored novel CREs and promoter structures in rice using bioinformatics approaches with this microarray data. We first performed network analyses to predict Fe excess-related CREs through the categorization of the gene expression patterns of Fe excess-responsive transcriptional regulons, and found four major expression clusters: Fe storage type, Fe chelator type, Fe uptake type, and WRKY and other co-expression type. Next, we explored CREs within these four clusters of gene expression types using a machine-learning method called microarray-associated motif analyzer (MAMA), which we previously established. Through a comprehensive bioinformatics approach, we identified a total of 560 CRE candidates extracted by MAMA analyses and 42 important conserved sequences of CREs directly related to the Fe excess response in various rice tissues. We explored several novel cis-elements as candidate Fe excess CREs including GCWGCWGC, CGACACGC, and Myb binding-like motifs. Based on the presence or absence of candidate CREs using MAMA and known PLACE CREs, we found that the Boruta-XGBoost model explained expression patterns with high accuracy of about 83%. Enriched sequences of both novel MAMA CREs and known PLACE CREs led to high accuracy expression patterns. We also found new roles of known CREs in the Fe excess response, including the DCEp2 motif, IDEF1-, Zinc Finger-, WRKY-, Myb-, AP2/ERF-, MADS- box-, bZIP and bHLH- binding sequence-containing motifs among Fe excess-responsive genes. In addition, we built a molecular model and promoter structures regulating Fe excess-responsive genes based on new finding CREs. Together, our findings about Fe excess-related CREs and conserved sequences will provide a comprehensive resource for discovery of genes and transcription factors involved in Fe excess-responsive pathways, clarification of the Fe excess response mechanism in rice, and future application of the promoter sequences to produce genotypes tolerant of Fe excess.

5.
Mol Nutr Food Res ; 65(16): e2100185, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33793045

RESUMEN

SCOPE: Grains of Paradise (GOP), the seeds of Aframomum melegueta, has anti-obesity effects. However, the mechanisms underlying the effects remain unclear. METHODS AND RESULTS: This study sets up to study the anti-obesity impact and homeostatic effects of 6-paradol, a major vanilloid found in GOP, and investigates the physiological outputs and the lipometabolism-related gene in fat and liver in high-fat-induced obese mice with a comparison with structurally similar vanilloids (6-gingerol and 6-shogaol). The vanilloids are synthesized in adequate quantities for performing animal experiments and orally administered to 6-week-old male mice over 2 weeks. This study found that 6-paradol decreased body weight gain and visceral and subcutaneous fats in 2 weeks, whereas 6-gingerol and 6-shogaol have no effect. Additionally, 6-paradol suppresses the hepatic cholesterol and triglyceride and significantly decreases the gene expression related to fatty acid synthesis, lipid transportation, and adipocyte differentiation in both liver and adipose tissue. Moreover, phosphorylation of AMP-activated protein kinase (AMPK) that greatly contributes to lipometabolism is promoted by 6-gingerol but not 6-paradol. CONCLUSION: These results suggest that 6-paradol regulates several obesity-related genes in an AMPK-independent manner. Therefore, it could be the principal active vanilloid in GOP giving it anti-obesity properties with a different mechanism.


Asunto(s)
Fármacos Antiobesidad/farmacología , Guayacol/análogos & derivados , Cetonas/farmacología , Obesidad/tratamiento farmacológico , Zingiberaceae/química , Proteínas Quinasas Activadas por AMP/metabolismo , Tejido Adiposo , Animales , Guayacol/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Estructura Molecular , Obesidad/genética , Extractos Vegetales/farmacología , Semillas/química , Aumento de Peso
6.
J Nat Prod ; 83(7): 2087-2092, 2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32644811

RESUMEN

In this study, three new garcinoic acid dimers, δ,δ-bigarcinoic acid (1), δ,δ-bi-O-garcinoic acid (2), and γ,δ-bi-O-garcinoic acid (3), and a new benzophenone derivative, (8E)-4-geranyl-3,5-dihydroxybenzophenone (4), as well as seven known compounds (5-11) were isolated from the seeds of Garcinia kola. The structures of the new compounds were elucidated using MALDI-TOF-MS and spectroscopic data, including 1D and 2D NMR and electronic circular dichroism spectra. All of the isolated compounds were evaluated for their antimicrobial activity against two oral pathogens, Porphyromonas gingivalis and Streptococcus sobrinus. Among them, 4 and δ-garcinoic acid (6) exhibited antimicrobial activity against both of these microorganisms (MICs of 31.3-62.5 µM for P. gingivalis and 15.6-31.3 µM for S. sobrinus). These results indicate that some chemical constituents in G. kola seeds have potential application in the prevention of oral diseases.


Asunto(s)
Antibacterianos/farmacología , Benzofenonas/farmacología , Benzopiranos/farmacología , Garcinia kola/metabolismo , Boca/microbiología , Extractos Vegetales/farmacología , Porphyromonas gingivalis/efectos de los fármacos , Semillas/química , Streptomyces/efectos de los fármacos , Antibacterianos/química , Benzofenonas/aislamiento & purificación , Benzopiranos/química , Cromatografía Líquida de Alta Presión , Humanos , Pruebas de Sensibilidad Microbiana , Análisis Espectral/métodos
7.
Org Lett ; 20(14): 4204-4208, 2018 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-29963866

RESUMEN

Ligand-controlled non-decarbonylative and decarbonylative conversions of acyl fluorides were developed using a Pd(OAc)2/Et3SiH combination. When tricyclohexylphosphine (PCy3) was used as the ligand, aldehydes were obtained as simple reductive conversion products. The use of 1,2-bis(dicyclohexylphosphino)ethane (Cy2P(CH2)2PCy2, DCPE) as the ligand, however, favored the formation of hydrocarbons, which are decarbonylative reduction products.

8.
Foot Ankle Surg ; 24(3): e13-e17, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29933964

RESUMEN

Isolated avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal without injury of the tarsometatarsal joint is very rare. Similar to most avulsion fractures, this type of injury is caused by strong tension exerted by the peroneus longus tendon. The mechanism leading to this lesion and treatment options are not clearly defined. Several surgical techniques have been advocated for this fracture, including excision of an avulsion fragment and open reduction for internal fixation through the medial aspect of the foot or minimal plantar incision. We have described a method of percutaneous fixing of the avulsion fracture at the plantar lateral base of the first metatarsal using the ZipTight Fixation System (Zimmer Biomet Warsaw, Indiana, USA), which offers the advantage of allowing a rigid fixation and minimal invasive surgical technique for a small fragment.


Asunto(s)
Fijación Interna de Fracturas/instrumentación , Fracturas por Avulsión/cirugía , Fracturas Óseas/cirugía , Huesos Metatarsianos/cirugía , Adulto , Diseño de Equipo , Fracturas por Avulsión/diagnóstico , Fracturas Óseas/diagnóstico , Humanos , Masculino , Huesos Metatarsianos/diagnóstico por imagen , Huesos Metatarsianos/lesiones , Tendones/cirugía , Tomografía Computarizada por Rayos X
9.
J Sci Food Agric ; 98(12): 4742-4748, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29542131

RESUMEN

BACKGROUND: Grains of paradise (GP) is the seed of Aframomum melegueta, which is widely distributed throughout West Africa and has been used as a spice and a folk remedy for a long time. Anti-obesity effect of GP intake was demonstrated in a previous report. Aim of the present study was to isolate some compounds in GP and clarify the anti-obesity mechanism. RESULTS: Ten vanilloid compounds were isolated. Among them, 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-ol and 1-(4'-hydroxy-3'-methoxyphenyl)-3-octen-5-one were determined as novel compounds and 6-gingerol, 6-paradol and 6-shogaol were identified as the major constituents in GP extract. Moreover, the extract and 6-gingerol, which is one of the principal components of GP extract, were orally administered to rats to investigate the effect on sympathetic nerve activity (SNA) in brown adipose tissue (BAT). The injection of GP extract and 6-gingerol decreased BAT-SNA, whereas capsaicin, which is a major component of chili pepper, activates the sympathetic nervous system. CONCLUSION: This study suggested that GP extract and 6-gingerol were largely unrelated to the anti-obesity effect by the activation of interscapular BAT-SNA and had a different anti-obesity mechanism to capsaicin. © 2018 Society of Chemical Industry.


Asunto(s)
Obesidad/fisiopatología , Extractos Vegetales/química , Sistema Nervioso Simpático/diagnóstico por imagen , Zingiberaceae/química , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Pardo/inervación , Animales , Catecoles/administración & dosificación , Catecoles/química , Alcoholes Grasos/administración & dosificación , Alcoholes Grasos/química , Guayacol/administración & dosificación , Guayacol/análogos & derivados , Guayacol/química , Humanos , Cetonas/administración & dosificación , Cetonas/química , Estructura Molecular , Obesidad/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Ratas , Semillas/química , Sistema Nervioso Simpático/fisiopatología
10.
J Nat Med ; 72(2): 474-480, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29332193

RESUMEN

In order to identify a novel whitening agent, the methanol extract of S. polyanthum leaf was focused on by the screening test using nine Indonesian medicinal plants for the inhibition of melanogenesis and tyrosinase activity in B16 melanoma cells. Three novel compounds [(1) 1-(2,3,5-trihydroxy-4-methylphenyl)hexane-1-one, (2) 1-(2,3,5-trihydroxy methylphenyl)octane-1-one, and (3) (4E)-1-(2,3,5-trihydroxy-4-methylphenyl)decan-1-one and one known compound [(4) 1-(2,3,5-trihydroxy-4-methylphenyl)decan-1-one were isolated from the methanol extract. Our study demonstrated that S. polyanthum leaf methanol extract at 25-200 µg/mL decreased extracellular melanin formation ca. 20-80%, with high cell viability. Compounds 1-4 were found to be active in melanogenesis and tyrosinase inhibition. Compound 3 was the most active against tyrosinase activity (83.98 µM), particularly when L-tyrosine was the substrate. Compounds 1-4 significantly diminished extracellular melanin formation in B16 melanoma cells (> 80%), with high cell viability. Thus, our study suggested that compounds 1-4 isolated from the methanol extract of S. polyanthum leaf play important roles in decreasing extracellular melanogenesis and inhibiting tyrosinase.


Asunto(s)
Melaninas/antagonistas & inhibidores , Extractos Vegetales/química , Plantas Medicinales/química , Syzygium/química
12.
Plant Cell Physiol ; 58(9): 1486-1493, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28922748

RESUMEN

Incidents at the Fukushima and Chernobyl nuclear power stations have resulted in widespread environmental contamination by radioactive nuclides. Among them, 137cesium has a 30 year half-life, and its persistence in soil raises serious food security issues. It is therefore important to prevent plants, especially crop plants, from absorbing radiocesium. In Arabidopsis thaliana, cesium ions are transported into root cells by several different potassium transporters such as high-affinity K+ transporter 5 (AtHAK5). Therefore, the cesium uptake pathway is thought to be highly redundant, making it difficult to develop plants with low cesium uptake. Here, we isolated rice mutants with low cesium uptake and reveal that the Oryza sativa potassium transporter OsHAK1, which is expressed on the surfaces of roots, is the main route of cesium influx into rice plants, especially in low potassium conditions. During hydroponic cultivation with low to normal potassium concentrations (0-206 µM: the normal potassium level in soil), cesium influx in OsHAK1-knockout lines was no greater than one-eighth that in the wild type. In field experiments, knockout lines of O. sativa HAK1 (OsHAK1) showed dramatically reduced cesium concentrations in grains and shoots, but their potassium uptake was not greatly affected and their grain yields were similar to that of the wild type. Our results demonstrate that, in rice roots, potassium transport systems other than OsHAK1 make little or no contribution to cesium uptake. These results show that low cesium uptake rice lines can be developed for cultivation in radiocesium-contaminated areas.


Asunto(s)
Cesio/metabolismo , Genes de Plantas , Proteínas de Transporte de Membrana/genética , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo , Potasio/metabolismo , Radioisótopos de Cesio/metabolismo , Contaminación Ambiental , Prueba de Complementación Genética , Proteínas de Transporte de Membrana/metabolismo , Modelos Biológicos , Mutagénesis/genética , Mutación/genética , Oryza/efectos de los fármacos , Fenotipo , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Potasio/farmacología , Soluciones
13.
Pharmacol Biochem Behav ; 153: 1-11, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27940067

RESUMEN

Central ghrelin is required for the rewarding properties of drug abuse. We investigated whether alcohol affects ghrelinergic, dopaminergic, and serotoninergic neurons and growth hormone secretagogue receptor 1A (GHS-R1A) levels in the reward system of the brain. Alcohol-naïve C57BL/6J mice received 2g/kg ethanol (EtOH) intraperitoneally (i.p.). Plasma ghrelin levels decreased between 1 and 4h. We investigated the effects of EtOH administration on plasma ghrelin levels in two different animal models at 1, 3, and 10months of age. Plasma ghrelin levels decreased following the EtOH treatment in 1- and 3-month-old short-term (1-day) alcohol vapor-exposed (STA) mice. In contrast, EtOH administration increased plasma ghrelin levels in 1- and 3-month-old long-term (20-day) alcohol vapor-exposed (LTA) mice. In vivo ghrelin release in the lateral hypothalamus (LH) increased in STA and LTA mice after the i.p. administration of EtOH. EtOH increased in vivo dopamine (DA), but not serotonin (5-HT) release in the LH of STA mice, and increased in vivo DA and 5-HT release in the LH of LTA mice. GHS-R1A mRNA expression and GHS-R1A protein levels in the LH were increased in LTA mice. The number of GHS-R1A-immunoreactive cells was greater in the LH and amygdala of LTA mice. These results support the neurobiological correlation between the development of drinking behavior and activation of ghrelinergic and serotonergic neurons in the LH. The activation of ghrelinergic systems in the amygdala may also induce an increase in 5-HT release in the LH during long-term alcohol intake.


Asunto(s)
Consumo de Bebidas Alcohólicas , Amígdala del Cerebelo/fisiología , Ghrelina/fisiología , Área Hipotalámica Lateral/fisiología , Neuronas Serotoninérgicas/fisiología , Animales , Dopamina/metabolismo , Ghrelina/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Receptores de Ghrelina/análisis , Receptores de Ghrelina/genética , Receptores de Ghrelina/fisiología , Serotonina/metabolismo
14.
J Appl Clin Med Phys ; 17(1): 353-359, 2016 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-26894360

RESUMEN

We clarified the relationship between the display size of MRI images and observer performance using a digital contrast-detail (d-CD) phantom. The d-CD phantom was developed using Microsoft Visual Basic 2010 Express. It had a 512 × 512 matrix in size and a total of 100 holes, whose diameter increased stepwise from 4 to 40 pixels with a 4-pixel interval in the vertical direction; the contrast varied stepwise in the horizontal direction. The digital driving level (DDL) of the back-ground, the width of the DDL, and the contrast were adjustable. These parameters were determined on the basis of the actual T1-weighted magnetic resonance (MR) images of the brain. In this study, the DDL, width, and contrast were set to 85, 20, and 1, respectively. The observer performance study was performed for three different display sizes (30 cm × 30 cm as the enlarged size, 16 cm × 16 cm as the original size, and 10 cm × 10 cm as the reduced size) using a 2-megapixel color liquid crystal display monitor, and it was analyzed using Friedman and Wilcoxon statistical tests. The observer performances for the original display (p < 0.01) and the reduced display sizes (p < 0.01) were superior to that observed for the enlarged size, whereas there was no significant difference between the original display and reduced display sizes (p = 0.31). Evaluation with the digital phantom simulating MR imaging also revealed that the original and reduced display sizes were superior to the enlarged display size in observer performance. The d-CD phantom enables a short-term evaluation of observer performance and is useful in analyzing relation-ship between display size and observer performance.


Asunto(s)
Mapeo Encefálico/normas , Encéfalo/anatomía & histología , Procesamiento de Imagen Asistido por Computador/normas , Imagen por Resonancia Magnética/normas , Fantasmas de Imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica/métodos
16.
J Toxicol Sci ; 38(4): 571-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23824013

RESUMEN

T-cell dependent antibody response (TDAR) incorporating both primary and secondary responses to keyhole limpet hemocyanin (KLH) in canine models have not yet been fully understood. To develop a practical dog TDAR model, we characterized primary and secondary antibody responses by intravenous or intramuscular immunization of KLH twice at intervals of 8 days during a 28-day course of study. Primary immunization with KLH by both routes induced a maximum IgM response on 6 to 8 days after the treatment, whereas the IgG response started 6 to 8 days after the treatment with relatively low levels. Remarkable increases in anti-KLH IgG levels (about 10-times compared with the primary response) were produced 5 to 7 days after the secondary KLH immunization by both routes. These results indicate that IgM-predominant and IgG-predominant responses were respectively induced by the primary and secondary immunization. Furthermore, the intravenous route showed higher baseline titers of primary and secondary anti-KLH IgM responses, suggesting that intravenous immunization of KLH might be a more suitable method for immunotoxicity evaluation. No remarkable inter-individual variability was noted in our canine models. Treatment with cyclophosphamide at 2 mg/kg/day for a consecutive 28 days significantly suppressed primary and secondary anti-KLH IgM and IgG responses induced by KLH injection on Days 15 and 23 of CPA treatment. These results demonstrate that these experimental designs could provide valuable information about the influence on both the primary and secondary humoral immune responses in dogs when exposed to potential immunomodulatory drugs.


Asunto(s)
Adyuvantes Inmunológicos , Formación de Anticuerpos/inmunología , Hemocianinas/inmunología , Inmunidad Humoral/inmunología , Inmunización Secundaria , Linfocitos T/inmunología , Animales , Ciclofosfamida/farmacología , Perros , Femenino , Hemocianinas/administración & dosificación , Humanos , Inmunoglobulina G/sangre , Inmunosupresores/farmacología , Inyecciones Intramusculares , Inyecciones Intravenosas , Masculino
17.
J Exp Bot ; 64(4): 1073-81, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23364937

RESUMEN

Glutathione is a tripeptide involved in various aspects of plant metabolism. This study investigated the effects of the reduced form of glutathione (GSH) applied to specific organs (source leaves, sink leaves, and roots) on cadmium (Cd) distribution and behaviour in the roots of oilseed rape plants (Brassica napus) cultured hydroponically. The translocation ratio of Cd from roots to shoots was significantly lower in plants that had root treatment of GSH than in control plants. GSH applied to roots reduced the Cd concentration in the symplast sap of root cells and inhibited root-to-shoot Cd translocation via xylem vessels significantly. GSH applied to roots also activated Cd efflux from root cells to the hydroponic solution. Inhibition of root-to-shoot translocation of Cd was visualized, and the activation of Cd efflux from root cells was also shown by using a positron-emitting tracer imaging system (PETIS). This study investigated a similar inhibitory effect on root-to-shoot translocation of Cd by the oxidized form of glutathione, GSSG. Inhibition of Cd accumulation by GSH was abolished by a low-temperature treatment. Root cells of plants exposed to GSH in the root zone had less Cd available for xylem loading by actively excluding Cd from the roots. Consequently, root-to-shoot translocation of Cd was suppressed and Cd accumulation in the shoot decreased.


Asunto(s)
Brassica napus/metabolismo , Cadmio/metabolismo , Glutatión/farmacología , Raíces de Plantas/efectos de los fármacos , Brotes de la Planta/efectos de los fármacos , Transporte Biológico , Brassica napus/efectos de los fármacos , Cadmio/farmacología , Cromatografía Líquida de Alta Presión , Oxidación-Reducción , Células Vegetales/efectos de los fármacos , Células Vegetales/metabolismo , Exudados de Plantas/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Temperatura , Xilema/efectos de los fármacos , Xilema/metabolismo , Zinc/metabolismo
18.
J Immunotoxicol ; 10(1): 40-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22953734

RESUMEN

To develop a rat T-cell-dependent antibody response (TDAR) model evaluating both primary and secondary antibody responses, keyhole limpet hemocyanin (KLH) was used to immunize rats twice during a 14-day course of study, a pattern closely linked to that of a short-term general toxicity study. Female rats of four representative strains (e.g., Sprague-Dawley, Wistar, Fischer, and Lewis) were immunized twice with intravenous administrations of KLH (300 µg/rat) on Days 5 and 9 during a 14-day treatment regimen with cyclophosphamide (CPA) at 1, 3, or 6 mg/kg/day. The primary and secondary immunizations of KLH markedly elevated serum anti-KLH IgM and IgG levels in all strains on Days 9 and 15. Remarkable higher levels of anti-KLH IgG (≈ 1000 µg/ml) were noted in all strains, which were more than 4-times compared with those of anti-KLH IgM levels at Day 9, indicating that predominant IgG reactions were induced by the dual immunizations. A large inter-individual variability in KLH-specific IgM and IgG production was observed in all strains. However, levels of the KLH-specific antibodies were considered sufficient for the evaluation, even in Sprague-Dawley and Wistar rats reported as strains with a wide range of variability since immunosuppression of CPA on responses in both anti-KLH IgM and IgG were observed in all strains to the same extent. In addition, the sensitivity of the KLH-ELISA assay system detecting the immunosuppressive effects of CPA was comparable to other assay systems with PFC assay or ELISA using SRBC. The results here demonstrated that these experimental designs could provide valuable information about the influence on both the primary and secondary humoral immune responses in rats when exposed to potential immunomodulatory drugs. Furthermore, the design of the presented TDAR study would support comprehensive evaluation together with the outcome of the conventional general toxicity study.


Asunto(s)
Formación de Anticuerpos , Hemocianinas/inmunología , Memoria Inmunológica , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Femenino , Inmunización Secundaria , Activación de Linfocitos , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Ratas Sprague-Dawley , Ratas Wistar
19.
Bone ; 53(1): 87-93, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23238125

RESUMEN

Sialic acid-binding immunoglobulin-like lectin 15 (Siglec-15) is a cell surface receptor for sialylated glycan ligands. Recent in vitro studies revealed upregulated Siglec-15 expression in differentiated osteoclasts and inhibition of osteoclast differentiation by anti-Siglec-15 polyclonal antibody, demonstrating Siglec-15 involvement in osteoclastogenesis. To discern the physiological role of Siglec-15 in skeletal development and osteoclast formation and/or function in vivo, we generated Siglec-15-deficient (siglec-15(-/-)) mice and analyzed their phenotype. The siglec-15(-/-) mice developed without physical abnormalities other than increased trabecular bone mass in lumbar vertebrae and metaphyseal regions of the femur and tibia, causing mild osteopetrosis. Histological analyses demonstrated that the number of osteoclasts present on the femoral trabecular bone of the mutant mice was comparable to that of the wild-type mice. However, urinary deoxypyridinoline, a systemic bone resorption marker, decreased in the siglec-15(-/-) mice, indicating that impaired osteoclast function was responsible for increased bone mass in the mutant mice. In addition, the ability of bone marrow-derived monocytes/macrophages from the siglec-15(-/-) mice to differentiate into osteoclasts was impaired, as determined in vitro by cellular tartrate-resistant acid phosphatase activity in response to the receptor activator of nuclear factor-κB ligand or tumor necrosis factor-α. These results reveal the importance of Siglec-15 in the regulation of osteoclast formation and/or function in vivo, providing new insights into osteoclast biology.


Asunto(s)
Diferenciación Celular , Inmunoglobulinas/fisiología , Proteínas de la Membrana/fisiología , Osteoclastos/citología , Osteopetrosis/patología , Absorciometría de Fotón , Animales , Densidad Ósea , Femenino , Inmunoglobulinas/genética , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados
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