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1.
Environ Microbiol ; 24(3): 1308-1325, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34708512

RESUMEN

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.


Asunto(s)
Antozoos , Cianobacterias , Microbiota , Poríferos , Animales , Antozoos/microbiología , Arrecifes de Coral , Cianobacterias/metabolismo , Poríferos/genética , Prevalencia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Simbiosis
2.
Int J Mol Sci ; 20(6)2019 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-30884842

RESUMEN

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.


Asunto(s)
Ficus/genética , Fotosíntesis/genética , Proteínas de Plantas/genética , Transcriptoma/genética , Arabidopsis/genética , Hidrolasas de Éster Carboxílico/genética , Clorofila/genética , Cloroplastos/genética , Ficus/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Proteolisis , Tilacoides/genética
3.
Physiol Plant ; 164(4): 452-466, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30054915

RESUMEN

Abiotic stresses affect crop plants and cause decreases in plant quality and productivity. Plants can overcome environmental stresses by activating molecular networks, including signal transduction, stress perception, metabolite production and expressions of specific stress-related genes. Recent research suggests that chemical priming is a promising field in crop stress management because plants can be primed by chemical agents to increase their tolerance to various environmental stresses. We present a concept to meet this objective and protect plants through priming of existing defense mechanisms avoiding manipulation of the genome. In addition, recent developments in plant molecular biology include the discovery of genes related to stress tolerance, including functional genes for protecting cells and regulatory genes for regulating stress responses. Therefore, enhancing abiotic stress tolerance using a transgenic approach to transfer these genes into plant genomes has attracted more investigations. Both chemical priming agents and genetic engineering can enhance regulatory and functional genes in plants and increase stress tolerance of plants. This review summarizes the latest findings of chemical priming agents and major achievements in molecular approaches that can potentially enhance the abiotic stress tolerance of plants.


Asunto(s)
Estrés Fisiológico/fisiología , Biotecnología , Regulación de la Expresión Génica de las Plantas/fisiología , Plantas
4.
Int J Mol Sci ; 19(3)2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29494547

RESUMEN

Plants of the genus Calathea possess many leaf colors, and they are economically important because they are widely used as ornamentals for interior landscaping. Physiological performances and photosynthetic capacities of C. insignis and C. makoyana were investigated. The photosynthetic efficiencies of C. insignis and C. makoyana were significantly increased when the photosynthetic photon flux density (PPFD) increased from 0 to 600 µmol photons·m-2·s-1 and became saturated with a further increase in the PPFD. The two Calathea species had lower values of both the light saturation point and maximal photosynthetic rate, which indicated that they are shade plants. No significant differences in predawn Fv/Fm values (close to 0.8) were observed between dark-green (DG) and light-green (LG) leaf sectors in all tested leaves. However, the effective quantum yield of photosystem II largely decreased as the PPFD increased. An increase in the apparent photosynthetic electron transport rate was observed in both species to a maximum at 600 µmol·m-2·s-1 PPFD, following by a decrease to 1500 µmol·m-2·s-1 PPFD. Compared to LG leaf extracts, DG leaf extracts contained higher levels of chlorophyll (Chl) a, Chl b, Chls a + b, carotenoids (Cars), anthocyanins (Ants), flavonoids (Flas), and polyphenols (PPs) in all plants, except for the Ant, Fla and PP contents of C. insignis plants. Calathea insignis also contained significantly higher levels of total protein than did C. makoyana. The adjusted normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), red-green, and flavonol index (FlavI) were significantly correlated to leaf Chls a + b, Cars, Ants, and Flas in C. makoyana, respectively, and can be used as indicators to characterize the physiology of these plants.


Asunto(s)
Fenómenos Químicos , Marantaceae/química , Marantaceae/metabolismo , Fotosíntesis , Clorofila/metabolismo , Luz , Fotones , Pigmentos Biológicos/biosíntesis , Hojas de la Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Metabolismo Secundario
5.
BMC Plant Biol ; 15: 61, 2015 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-25849781

RESUMEN

BACKGROUND: The source and sink relationships between insect-induced galls and host plant leaves are interesting. In this research, we collected cup-like galls induced by Bruggmanniella sp. (Diptera: Cecidomyiidae) on host leaves of Litsea acuminata and assessed them to investigate source-sink relationships between galls and host leaves. We characterized several of their photosynthetic characteristics including chlorophyll fluorescence (Fv/Fm), stomatal conductance, and photosynthetic capacity, biochemical components such as total soluble sugar, starches, free amino acids, and soluble proteins. The structural analyses were performed under confocal, light, and scanning electron microscopies. RESULTS: Compared with host leaves, galls exhibited slightly lower chlorophyll fluorescence; however, stomatal conductance and photosynthetic capacity were not detected at all. Galls accumulated higher total soluble sugars and free amino acids but less soluble proteins than host leaves. No stomata was observed on exterior or interior gall surfaces under light or scanning electron microscopy, but their inner surfaces were covered with fungal hyphae. Confocal imagery showed a gradient of chloroplasts distribution between gall outer and inner surfaces. CONCLUSIONS: Our results strongly suggest that leaf-derived cecidomyiid galls are a type of chlorophyll-deficient non-leaf green tissue and consists on a novel sink in L. acuminate.


Asunto(s)
Litsea/fisiología , Litsea/parasitología , Fotosíntesis , Hojas de la Planta/fisiología , Tumores de Planta/parasitología , Aminoácidos/metabolismo , Animales , Metabolismo de los Hidratos de Carbono/efectos de la radiación , Dióxido de Carbono/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/efectos de la radiación , Cloroplastos/ultraestructura , Dípteros/fisiología , Fluorescencia , Litsea/efectos de la radiación , Malondialdehído/metabolismo , Fotosíntesis/efectos de la radiación , Hojas de la Planta/efectos de la radiación , Proteínas de Plantas/metabolismo , Solubilidad , Almidón/metabolismo
6.
Physiol Plant ; 152(3): 475-85, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24621096

RESUMEN

Three relevant hypotheses - nutrition, environment and the enemies hypothesis - often invoked to explore source and sink relationships between galls and their host plants are still under dispute. In this research, chlorophyll fluorescence, gas exchange capacity, stomatal conductance, total carbon and nitrogen, total soluble sugars and starches, and scanning and transmission electron microscopy of two types of galls were used to investigate source-sink relationships. Compared with host leaves, these galls demonstrated slightly lower chlorophyll fluorescence; however, gas exchange capacity and stomatal conductance were not detected at all. Scanning electron micrographs demonstrated that the abaxial epidermis of host leaves contain normal amounts of stomata, whereas no stomata were observed on the exterior and interior surfaces of both types of galls. In addition, gall inner surfaces were covered with many kinds of fungal hyphae. Gall total carbon (C) and nitrogen (N) levels were lower but the C/N ratio was higher in galls than host leaves. Both types of galls accumulated higher total soluble sugars and starches than host leaves. Transmission electron micrographs also revealed that both types of galls contain plastoglobuli and giant starch granules during gall development. Results strongly indicate that leaf-derived cecidomyiid galls are sinks in Machilus thunbergii leaves. However, it is perplexing how larvae cycle and balance CO(2) and O(2) in gall growth chambers without stomata.


Asunto(s)
Carbono/metabolismo , Dípteros/fisiología , Lauraceae/metabolismo , Nitrógeno/metabolismo , Tumores de Planta/parasitología , Animales , Transporte Biológico , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Interacciones Huésped-Parásitos , Lauraceae/parasitología , Lauraceae/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Fotosíntesis , Hojas de la Planta/metabolismo , Hojas de la Planta/parasitología , Hojas de la Planta/ultraestructura , Transpiración de Plantas
7.
Indian J Biochem Biophys ; 51(5): 388-95, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25630109

RESUMEN

The distribution of chlorophyll-related compounds (CRCs) derived from dietary spinach was investigated in different organs the rabbits. The rabbits in the experimental group consumed 100 g of freeze-dried spinach powder after a 24 h fasting period and sacrificed 2, 4, 8, 12 and 24 h later and in the control group sacrificed after the 24 h fasting period. The main CRCs in the liver were found to be chlorophyll (Chl a) and b, chlorophyllide (Chlide) a and b, pheophytin (Phe) a and b and pheophorbide (Pho) a and b, which reached their peak values at 8 h post-feeding. The gallbladder contained mainly Chlide a and a', Pho a and a', Pho b and b', which peaked their values at 2 h post-feeding. Pho a and b were consistently observed in the blood and peaked at 12 h post-feeding. The earlier appearance of Chlide a', Pho a' and Pho b' in the gallbladder compared to the liver indicated that these CRCs were compartmentalized differently and might undergo the same type of vectorialized transport as characterized for the bile salts. Pho levels peaked later in the blood compared to the liver, suggesting that Pho might be released into the peripheral blood circulation from the liver. In conclusion, Chlide and Pho were the principal Chl metabolites in the rabbits. Our data may expand our understanding of the metabolism and biodistribution of CRCs in the human body. A number of biological functions, including anti-oxidation, anti-tumor and anti-aging have recently been attributed to CRCs, it will be interesting to explore, if the binding of Chlide and Pho to other nutrients or trace metal ions in the body mediate their biological functions.


Asunto(s)
Clorofila/metabolismo , Ingestión de Alimentos/fisiología , Especificidad de Órganos/fisiología , Periodo Posprandial/fisiología , Spinacia oleracea/química , Animales , Femenino , Tasa de Depuración Metabólica , Conejos , Distribución Tisular
8.
BMC Nutr ; 6: 26, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32655873

RESUMEN

BACKGROUND: Goji (Lycium) is a popular traditional health food, and its fruit and root extracts have been found to possess antioxidant, anti-inflammatory, and hypocholesterolemia-inducing abilities. Goji leaves also contain high amounts of phenolic compounds, similar to its fruit, and their extracts also exhibit several pharmaceutical effects. The induction of galls on Goji leaves reduces their photosynthetic ability and fruit yield, which raise their farming costs, thereby leading to economic loss. However, the defense mechanisms induced by infection may elevate the secondary metabolite content of the leaves, which might provide more nutritive compounds. METHOD: Content of chlorophyll, carotenoids, polyphenols, and flavonoids in the extracts of normal and infected Goji leaves (L. chinense) were analyzed. The relative content of chlorogenic acid and rutin, two major phenolic compounds in Goji leaves, were determined by LC-MS/MS. Antioxidant activity was presented by demonstrating the DPPH scavenging percentage. The extract of Goji fruit (L. barbarum) was also analyzed to show a comparative result. RESULTS: In this study, we found that in infected Goji leaves, the polyphenol content was significantly increased. The level of chlorogenic acid was increased by 36% in galled leaves. The content of rutin in galled leaves was also elevated. Testing the antioxidant activities also showed that the extracts of galled leaves have higher DPPH scavenging abilities. CONCLUSIONS: Our results demonstrated that galled Goji leaves have higher functional value, and may have potential as being consumed as health food.

9.
Biochem Biophys Res Commun ; 380(4): 791-6, 2009 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-19338754

RESUMEN

Bone marrow stromal cells (MSCs) differentiation and proliferation are controlled by numerous growth factors and hormones. Continuous parathyroid hormone (PTH) treatment has been shown to decrease osteoblast differentiation, whereas pulsatile PTH increases osteoblast differentiation. However, the effects of PTH treatments on MSCs have not been investigated. This study showed continuous PTH treatment in the presence of dexamethasone (DEX) promoted osteogenic differentiation of rat MSCs in vitro, as demonstrated by increased alkaline phosphatase (ALP) activity, number of ALP expressing cells, and up-regulation of PTH receptor-1, ALP, and osteocalcin mRNA expressions. In contrast, pulsatile PTH treatment was found to suppress osteogenesis of rat MSCs, possibly by promoting the maintenance of undifferentiated cells. Additionally, the observed effects of PTH were strongly dependent on the presence of DEX. MSC proliferation however was not influenced by PTH independent of treatment regimen and presence or absence of DEX. Furthermore, our work raised the possibility that PTH treatment may modulate stem/progenitor cell activity within MSC cultures.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Osteogénesis , Hormona Paratiroidea/farmacología , Fosfatasa Alcalina/metabolismo , Animales , Células de la Médula Ósea/fisiología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Dexametasona/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Osteocalcina/metabolismo , Ratas , Receptor de Hormona Paratiroídea Tipo 1/agonistas , Células del Estroma/efectos de los fármacos , Células del Estroma/fisiología
10.
Pharm Res ; 26(7): 1644-56, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19384471

RESUMEN

PURPOSE: To develop and characterize the solid-state properties of poly(DL-lactic-co-glycolic acid) (PLGA) and poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) microspheres for the localized and controlled release of fusidic acid (FA). METHODS: The effects of FA loading and polymer composition on the mean diameter, encapsulation efficiency and FA released from the microspheres were determined. The solid-state and phase separation properties of the microspheres were characterized using DSC, XRPD, Raman spectroscopy, SEM, laser confocal and real time recording of single microspheres formation. RESULTS: Above a loading of 1% (w/w) FA phase separated from PLGA polymer and formed distinct spherical FA-rich amorphous microdomains throughout the PLGA microsphere. For FA-loaded PLGA microspheres, encapsulation efficiency and cumulative release increased with initial drug loading. Similarly, cumulative release from FA-loaded PHBV microspheres was increased by FA loading. After the initial burst release, FA was released from PLGA microspheres much slower compared to PHBV microspheres. CONCLUSIONS: A unique phase separation phenomenon of FA in PLGA but not in PHBV polymers was observed, driven by coalescence of liquid microdroplets of a DCM-FA-rich phase in the forming microsphere.


Asunto(s)
Antibacterianos/química , Preparaciones de Acción Retardada/química , Ácido Fusídico/química , Glicolatos/química , Microesferas , Poliésteres/química , Rastreo Diferencial de Calorimetría , Cinética , Ácido Láctico , Tamaño de la Partícula , Transición de Fase , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Difracción de Polvo , Propiedades de Superficie , Difracción de Rayos X
11.
Microbiome ; 7(1): 3, 2019 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-30609942

RESUMEN

BACKGROUND: Endolithic microbes in coral skeletons are known to be a nutrient source for the coral host. In addition to aerobic endolithic algae and Cyanobacteria, which are usually described in the various corals and form a green layer beneath coral tissues, the anaerobic photoautotrophic green sulfur bacteria (GSB) Prosthecochloris is dominant in the skeleton of Isopora palifera. However, due to inherent challenges in studying anaerobic microbes in coral skeleton, the reason for its niche preference and function are largely unknown. RESULTS: This study characterized a diverse and dynamic community of endolithic microbes shaped by the availability of light and oxygen. In addition, anaerobic bacteria isolated from the coral skeleton were cultured for the first time to experimentally clarify the role of these GSB. This characterization includes GSB's abundance, genetic and genomic profiles, organelle structure, and specific metabolic functions and activity. Our results explain the advantages endolithic GSB receive from living in coral skeletons, the potential metabolic role of a clade of coral-associated Prosthecochloris (CAP) in the skeleton, and the nitrogen fixation ability of CAP. CONCLUSION: We suggest that the endolithic microbial community in coral skeletons is diverse and dynamic and that light and oxygen are two crucial factors for shaping it. This study is the first to demonstrate the ability of nitrogen uptake by specific coral-associated endolithic bacteria and shed light on the role of endolithic bacteria in coral skeletons.


Asunto(s)
Antozoos/microbiología , Chlorobi/clasificación , Metagenómica/métodos , Animales , Chlorobi/genética , Chlorobi/aislamiento & purificación , ADN Bacteriano/genética , ADN Ribosómico/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
12.
PLoS One ; 13(10): e0205265, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30356295

RESUMEN

BACKGROUND: Insect galls are atypical plant tissues induced by the invasion of insects. Compared to the host leaf, gall tissues lose photosynthetic ability, but have higher soluble sugar content. Although the physiological and biochemical regulation of gall tissues have been demonstrated, the mechanism of genetic regulation has only been analyzed in few studies. RESULTS: In this study, the transcriptome of cup-shaped galls and its host leaf were de novo assembled. Cellular functional enrichment and differentially expressed gene groups in the gall tissues were analyzed. The genes associated with primary metabolism, including photosynthesis, cell wall turnover, and sugar degradation, were expressed differently in galls and leaves. The examination of gene expression demonstrated that the genes involved in brassinosteroid synthesis and responses exhibited a remarkable modulation in cup-shaped galls, suggesting a potential role of steroid hormones in regulating gall development. CONCLUSIONS: This study revealed the genetic responses, including those involved in source-sink reallocation and phytohormone metabolism, of galls induced by a dipteran insect.


Asunto(s)
Litsea/genética , Proteínas de Plantas/genética , Tumores de Planta/genética , Transcriptoma/genética , Animales , Metabolismo de los Hidratos de Carbono , Dípteros/genética , Dípteros/patogenicidad , Perfilación de la Expresión Génica/métodos , Interacciones Huésped-Parásitos/genética , Litsea/parasitología , Fotosíntesis/genética , Hojas de la Planta/genética , Tumores de Planta/parasitología
13.
J Photochem Photobiol B ; 187: 106-112, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30121420

RESUMEN

Anthocyanins (Ants) are water-soluble secondary metabolites that are responsible for red colour of plant leaves. To determine photosynthetic pigments, 80% acetone was used to extract Ants from Ant-containing leaves of test plants. However, using the 80% acetone extraction method can lead to interference between chlorophylls (Chls) and Ants. Porphyrins, such as protoporphyrin IX (PPIX), Mg-protoporphyrin IX (MgPP), and protochlorophyllide (Pchlide), are Chl biosynthetic intermediates and demonstrate photospectrometric characteristics similar to those of Chl. Although the ether/water extraction method was able to remove Ants interference when detecting porphyrins, the porphyrins extraction efficiency was lower than that of the 80% acetone extraction method. Low Ants levels interfered with individual porphyrin ratios, and the extent of the effect was correlated with Ants concentrations. We developed the three equations could eliminate interference by Ants when determining the porphyrin molecular percentage (%) and were comprehensively applied to all tested species of Ants-containing leaves.


Asunto(s)
Antocianinas/metabolismo , Hojas de la Planta/química , Porfirinas/metabolismo , Antocianinas/química , Clorofila/biosíntesis , Color , Ipomoea batatas/química , Ipomoea batatas/metabolismo , Hojas de la Planta/metabolismo , Porfirinas/química , Protoclorofilida/química , Protoclorofilida/metabolismo , Protoporfirinas/química , Protoporfirinas/metabolismo
14.
Chem Commun (Camb) ; 53(54): 7497-7500, 2017 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-28628175

RESUMEN

A novel protocol to prepare multi-substituted dihydrofuropyridine and dihydropyrrolopyridine derivatives from KOH-catalyzed reactions between readily available N-propargylic ß-enaminones and arylaldehydes or N-sulfonyl imines has been developed in moderate to good yields.

15.
Adv Drug Deliv Rev ; 58(3): 402-11, 2006 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-16616969

RESUMEN

Stent-based drug delivery system is a revolutionary approach to mitigate the negative affects of balloon angioplasty, improve immune responsiveness and prevent hyperplastic growth of smooth muscle in the restenotic state. Its success is therefore empirically associated with effective delivery of potent therapeutics to the target site at a therapeutic concentration, for a sufficient time, and in a biologically active form. However, local delivery with drug-eluting stents imparts large dynamic concentration gradients across tissues that can be difficult to identify, characterize and control. This review explores the factors such as physiological transport forces, drug physicochemical properties, local biological tissue properties and stent design that governs the local pharmacokinetics within the arterial wall by drug-eluting stent. Rational design and optimization of drug-eluting stents for local delivery thus requires a careful consideration of all these factors.


Asunto(s)
Fármacos Cardiovasculares/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Stents , Humanos , Modelos Cardiovasculares
16.
J Agric Food Chem ; 53(7): 2746-50, 2005 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-15796620

RESUMEN

Chlorophylls (Chl's) are the most abundant natural plant pigments. Four chlorophyll-related compounds (CRCs), including chlorophyllide a and b (Chlide a and b) and pheophorbide a and b (Pho a and b), were investigated for their antioxidative capacities to protect human lymphocyte DNA from hydrogen peroxide (H(2)O(2)) induced strand breaks and oxidative damage ex vivo. Lymphocytes exposed to H(2)O(2) at concentrations of 10 and 50 microM revealed an increased frequency of DNA single-strand breaks (ssb's; as measured by the comet assay) and also an increased level of oxidized nucleoside (as measured by 8-hydroxydeoxyguanosine, 8-OHdG). All Chl's reduced the level of DNA ssb's and 8-OHdG within human lymphocytes following exposure to 10 microM H(2)O(2). Only Pho a and b were able to decrease DNA ssb's and 8-OHdG following treatment of lymphocytes with 50 microM H(2)O(2), in a concentration-dependent fashion. It was demonstrated herein that Pho a and b were more antioxidative than others. We applied DPPH free-radical scavenge assays in vitro, and got similar results. Pho a and b had higher ability in scavenging capacities than others. We conclude that water-extract Chl's are able to enhance the ability of human lymphocytes to resist H(2)O(2)-induced oxidative damage, especially for Pho a and b.


Asunto(s)
Antioxidantes/farmacología , Clorofila/análogos & derivados , Clorofila/farmacología , Daño del ADN/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Linfocitos/química , Clorofilidas/farmacología , Humanos
17.
J Med Chem ; 58(4): 1929-39, 2015 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-25625541

RESUMEN

Development of a series of highly kinome-selective spleen tyrosine kinase (Syk) inhibitors with favorable druglike properties is described. Early leads were discovered through X-ray crystallographic analysis, and a systematic survey of cores within a selected chemical space focused on ligand binding efficiency. Attenuation of hERG ion channel activity inherent within the initial chemotype was guided through modulation of physicochemical properties including log D, PSA, and pKa. PSA proved most effective for prospective compound design. Further profiling of an advanced compound revealed bacterial mutagenicity in the Ames test using TA97a Salmonella strain, and subsequent study demonstrated that this mutagenicity was pervasive throughout the series. Identification of intercalation as a likely mechanism for the mutagenicity-enabled modification of the core scaffold. Implementation of a DNA binding assay as a prescreen and models in DNA allowed resolution of the mutagenicity risk, affording molecules with favorable potency, selectivity, pharmacokinetic, and off-target profiles.


Asunto(s)
Amidas/farmacología , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Bazo/enzimología , Amidas/síntesis química , Amidas/química , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Canales de Potasio Éter-A-Go-Go/genética , Canales de Potasio Éter-A-Go-Go/metabolismo , Humanos , Modelos Moleculares , Estructura Molecular , Pruebas de Mutagenicidad , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Tirosina Quinasas/metabolismo , Bazo/efectos de los fármacos , Relación Estructura-Actividad
18.
Nutrients ; 6(5): 2115-30, 2014 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-24858497

RESUMEN

The objectives of this study were to identify the antioxidants and antioxidant axtivity in 27 of Taiwan's indigenous vegetables. Lycium chinense (Lc), Lactuca indica (Li), and Perilla ocymoides (Po) contained abundant quercetin (Que), while Artemisia lactiflora (Al) and Gynura bicolor (Gb) were rich in morin and kaempferol, respectively. Additionally, Nymphoides cristata (Nc) and Sechium edule (Se)-yellow had significantly higher levels of myricetin (Myr) than other tested samples. Cyanidin (Cyan) and malvidin (Mal) were abundant in Gb, Abelmoschus esculentus Moench (Abe), Po, Anisogonium esculentum (Retz.) Presl (Ane), Ipomoea batatas (Ib)-purple, and Hemerocallis fulva (Hf)-bright orange. Relatively high levels of Trolox equivalent antioxidant capacity (TEAC), oxygen radical absorption capacity (ORAC), and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenger were generated from extracts of Toona sinensis (Ts) and Po. Significant and positive correlations between antioxidant activity and polyphenols, anthocyanidins, Que, Myr, and morin were observed, indicating that these phytochemicals were some of the main components responsible for the antioxidant activity of tested plants. The much higher antioxidant activity of Po, Ts, and Ib (purple leaf) may be related to their higher Cyan, Que, and polyphenol content.


Asunto(s)
Antioxidantes/análisis , Extractos Vegetales/química , Verduras/química , Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Quempferoles/análisis , Hojas de la Planta/química , Polifenoles/análisis , Especies Reactivas de Oxígeno , Taiwán
19.
Bot Stud ; 55(1): 11, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28510919

RESUMEN

BACKGROUND: Spectral reflectance was evaluated for its usefulness as a nondestructive estimation of chlorophyll (Chl) content from three cultivars of sweet potato (Ipomoea batatas L.) with green, yellow, and purple leaves grown in a greenhouse for 22 days. While the green and yellow leaves contain variant amount of photosynthetic pigments without or with little level of anthocyanins, the purple leaves, except large amount of photosynthetic pigments, have high quantity of anthocyanins. RESULTS: For green and yellow leaves, the reciprocal reflectance (R-1) and derived indices incorporating near infrared (NIR) reflectance, [(Rλ)-1 - (RNIR)-1] and [(RNIR/Rλ) - 1], in the green and red edge spectral ranges were shown to be strongly correlated (r2 = 0.8 ~ 0.9) with the chlorophyll content. The root mean square error (RMSE) of the chlorophyll content estimation using these indices was < 50 mg m-2. However, when purple leaves containing high levels of anthocyanins were included in the sample, R-1 in the green spectral range and the above-mentioned indices displayed much weaker correlations with the chlorophyll content. The RMSE of chlorophyll estimation using these indices in the green spectral range sharply increased to > 110 mg m-2 when the sample included purple leaves. The new index, [1 - (Rλ/RNIR)], was therefore inferred and developed to eliminate the distorting effect of anthocyanins on chlorophyll content estimation using reflectance in the green spectral range. For leaves with high levels of anthocyanins, the correlation between [1 - (Rλ/RNIR)] and the chlorophyll content remained strong (r2 = 0.8 ~ 0.9) in the green spectral range, and the RMSE was minimal. CONCLUSION: The reflectance index, [1 - (Rλ/RNIR)], therefore represents a new and useful parameter for estimating leaf chlorophyll content in leaves with any level of anthocyanins such as purple rice leaf.

20.
BMC Res Notes ; 6: 490, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24279749

RESUMEN

BACKGROUND: Herbaceous plants containing antioxidants can protect against DNA damage. The purpose of this study was to evaluate the antioxidant substances, antioxidant activity, and protection of DNA from oxidative damage in human lymphocytes induced by hydrogen peroxide (H2O2). Our methods used acidic methanol and water extractions from six herbaceous plants, including Bidens alba (BA), Lycium chinense (LC), Mentha arvensis (MA), Plantago asiatica (PA), Houttuynia cordata (HC), and Centella asiatica (CA). METHODS: Antioxidant compounds such as flavonol and polyphenol were analyzed. Antioxidant activity was determined by the inhibition percentage of conjugated diene formation in a linoleic acid emulsion system and by trolox-equivalent antioxidant capacity (TEAC) assay. Their antioxidative capacities for protecting human lymphocyte DNA from H2O2-induced strand breaks was evaluated by comet assay. RESULTS: The studied plants were found to be rich in flavonols, especially myricetin in BA, morin in MA, quercetin in HC, and kaemperol in CA. In addition, polyphenol abounded in BA and CA. The best conjugated diene formation inhibition percentage was found in the acidic methanolic extract of PA. Regarding TEAC, the best antioxidant activity was generated from the acidic methanolic extract of HC. Water and acidic methanolic extracts of MA and HC both had better inhibition percentages of tail DNA% and tail moment as compared to the rest of the tested extracts, and significantly suppressed oxidative damage to lymphocyte DNA. CONCLUSION: Quercetin and morin are important for preventing peroxidation and oxidative damage to DNA, and the leaves of MA and HC extracts may have excellent potential as functional ingredients representing potential sources of natural antioxidants.


Asunto(s)
Antioxidantes/farmacología , Medicamentos Herbarios Chinos/química , Flavonoles/farmacología , Linfocitos/efectos de los fármacos , Plantas Medicinales/química , Polifenoles/farmacología , Adulto , Antioxidantes/aislamiento & purificación , Bioensayo , Células Cultivadas , Cromanos/química , Ensayo Cometa , Femenino , Flavonoles/aislamiento & purificación , Humanos , Peróxido de Hidrógeno/farmacología , Ácido Linoleico/química , Peroxidación de Lípido/efectos de los fármacos , Linfocitos/citología , Linfocitos/metabolismo , Masculino , Metanol , Persona de Mediana Edad , Desnaturalización de Ácido Nucleico/efectos de los fármacos , Estrés Oxidativo , Polifenoles/aislamiento & purificación , Solventes , Agua
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