Publications by authors named "Peragon J"

Natural products have a significant role in the development of new drugs, being relevant the pentacyclic triterpenes extracted from . Anticancer effect of uvaol, a natural triterpene, has been scarcely studied. The aim of this study was to understand the anticancer mechanism of uvaol in the HepG2 cell line.

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Pentacyclic triterpenes and phenols are two types of bioactive molecules found in olive trees that have important activities related to health and disease prevention. Triterpenes, including oleanolic acid, maslinic acid, erythrodiol and uvaol, show antitumoral activities, and phenols such as oleuropein, tyrosol, and hydroxytyrosol are natural antioxidants. The concentration of these metabolites is considered a marker of the quality of olives and olive oil.

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Long-term starvation provokes a metabolic response in the brain to adapt to the lack of nutrient intake and to maintain the physiology of this organ. Here, we study the changes in the global proteomic profile of the rat brain after a seven-day period of food deprivation, to further our understanding of the biochemical and cellular mechanisms underlying the situations without food. We have used two-dimensional electrophoresis followed by mass spectrometry (2D-MS) in order to identify proteins differentially expressed during prolonged food deprivation.

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Background: Metabolic syndrome is a set of pathologies among which stand out the obesity, which is related to the lipid droplet accumulation and changes to cellular morphology regulated by several molecules and transcription factors. Maslinic acid (MA) is a natural product with demonstrated pharmacological functions including anti-inflammation, anti-tumor and anti-oxidation, among others.

Purpose: Here we report the effects of MA on the adipogenesis process in 3T3-L1 cells.

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NADPH plays a central role in reductive biosynthesis of membrane lipids, maintenance of cell integrity, protein synthesis and redox balance maintenance. Hence, NADPH is involved in the growth and proliferation processes. In addition, it has been shown that changes in nutritional conditions produced changes in NADPH levels and growth rate.

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Maslinic acid (MA) is a natural triterpene present in high concentrations in the waxy skin of olives. We have previously reported that MA induces apoptotic cell death via the mitochondrial apoptotic pathway in HT29 colon cancer cells. Here, we show that MA induces apoptosis in Caco-2 colon cancer cells via the extrinsic apoptotic pathway in a dose-dependent manner.

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Maslinic acid (MA) and oleanolic acid (OA), the main triterpenic acids present in olive, have important properties for health and disease prevention. MA selectively inhibits cell proliferation of the HT29 human colon-cancer cell line by inducing selective apoptosis. For measuring the MA and OA concentration inside the cell and in the culture medium, a new HPLC-MS procedure has been developed.

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Maslinic acid (MA) is a natural compound whose structure corresponds to a pentacyclic triterpene. It is abundant in the cuticular lipid layer of olives. MA has many biological and therapeutic properties related to health, including antitumor, anti-inflammatory, antimicrobial, antiparasitic, antihypertensive, and antioxidant activities.

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Purpose: We have previously reported that tyrosol (TYR) promotes lifespan extension in the nematode Caenorhabditis elegans, also inducing a stronger resistance to thermal and oxidative stress in vivo. In this study, we performed a whole-genome DNA microarray in order to narrow down the search for candidate genes or signaling pathways potentially involved in TYR effects on C. elegans longevity.

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Unlabelled: This study analyzes the nitrated protein profile of the rat-brain cortex in a model of hypoxia/reoxygenation, identifying the nitrated proteins and assessing spot changes. The proteins identified were grouped into categories, according to their function: 1) metabolism: pyruvate kinase (PK), α-enolase, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), phosphoglycerate mutase 1 (PGAM1), and glutamine synthetase (GS); 2) cytoskeletal proteins: α-tubulin, β-tubulin, γ-actin, and glial fibrillary acidic protein (GFAP); 3) chaperones: heat-shock protein 71kDa (HSP71); and 4) carrier proteins: voltage-dependent anion-selective channel protein 1 (VDAC-1) and Atp6v1a. PK, α-enolase, and GS nitration rates were upregulated, increasing progressively during reoxygenation and peaking at 24h.

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We report that a novel triterpenoid, (2a,3b)-2,3-dihydroxyolean-12-en-28-oic acid (maslinic acid), isolated from olive pomace from Olea europaea, triggers primarily the extrinsic and later the intrinsic apoptotic pathways in Caco-2 human colon-cancer cells. Apoptosis induced by maslinic acid was confirmed by FACS analysis using annexine-V FICT staining. This induction of apoptosis was correlated with the early activation of caspase-8 and caspase-3, the activation of caspase-8 was also correlated with higher levels of Bid cleavage and decreased Bcl-2, but with no change in Bax expression.

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Tyrosol (TYR, 2-(4-hydroxyphenyl)ethanol), one of the main phenols in olive oil and olive fruit, significantly strengthens resistance to thermal and oxidative stress in the nematode Caenorhabditis elegans and extends its lifespan. To elucidate the cellular functions regulated by TYR, we have used a proteomic procedure based on 2DE coupled with MS with the aim to identify the proteins differentially expressed in nematodes grown in a medium containing 250 μM TYR. After the comparison of the protein profiles from 250 μM TYR and from control, 28 protein spots were found to be altered in abundance (≥twofold).

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Pentacyclic triterpenoids are plant secondary metabolites of great interest for health and disease prevention. HPLC-UV/vis was used to determine the concentration of the pentacyclic triterpenoids present in fruits and leaves of Picual and Cornezuelo olive tree cultivars. Maslinic acid (MA) and oleanolic acid (OA) are the only two compounds present in fruits, MA being the more abundant.

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Unlabelled: Maslinic acid (MA) is an anti-tumoural agent which shows potent anti-proliferative properties against the HT29 colon-cancer cells. To shed light upon the active mechanism of MA we have investigated its effects upon the cytoskeleton. We used a proteomics procedure based on two-dimensional gel electrophoresis, mass analysis and peptide mass fingerprinting.

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Brain, due to its high metabolism, is severely affected by hypoxia/reoxygenation. In this study, cerebral cortexes from rats subjected to hypobaric hypoxia followed by several reoxygenation periods (0 h, 24 h, and 5 days) were compared with normobaric normoxic controls to identify protein-expression differences using proteomic approaches. Only 2-fold differences in spot abundance between controls and experimental groups from each reoxygenation period were considered.

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Maslinic acid (MA) is a pentacyclic triterpene used as a feed additive to stimulate growth, protein-turnover rates, and hyperplasia in fish. To further our understanding of cellular mechanisms underlying the action of MA, we have used 2-DE coupled with MS to identify proteins differentially expressed in the livers of juvenile gilthead sea bream (Sparus aurata) grown under fish-farm conditions and fed with a 100 mg/kg MA-enriched diet (MA(100)). After the comparison of the protein profiles from MA(100) fed fish and from control, 49 protein spots were found to be altered in abundance (≥2-fold).

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The kinetic behavior and protein-expression level of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) have been determined in the leaves of the olive tree (Olea europaea L.) of cv. Picual, Verdial, Arbequina, and Frantoio during fruit ripening.

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Background: Oleuropein (Ole), hydroxytyrosol (Htyr), and tyrosol (Tyr) are three of the main phenolic compounds present in the olive tree (Olea europaea L.) that have important antioxidant properties. To investigate the role of these phenolic compounds in the metabolism of stems and roots of Olea europaea L.

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We have determined the kinetic behaviour of serine dehydratase (SerDH) and tyrosine aminotransferase (TyrAT) in the liver and white muscle of juvenile rainbow trout (Oncorhynchus mykiss) fed on a low-protein/high-fat (LP/HF) and control diets. The relationship between the kinetic parameters and tissue-DNA concentration has also been determined. SerDH and TyrAT showed hyperbolic kinetics in all cases.

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The kinetics and protein-expression level of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) in fruits of olive trees (Olea europaea) cv. Picual, Verdial, Arbequina, and Frantoio have been studied in relation to the concentration of total phenolic compounds, oleuropein, hydroxytyrosol, and tyrosol during fruit ripening. Frantoio was the variety that showed the highest total phenol concentration, the highest PAL activity, the lowest PPO activity, and the lowest protein levels.

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Here, we study a cycle of long-term starvation followed by refeeding in relation to the kinetics of serine dehydratase (SerDH) and tyrosine aminotransferase (TyrAT) in rainbow trout (Oncorhynchus mykiss). We determine SerDH- and TyrAT- specific activity at different substrate concentrations in liver and white muscle of juvenile trout starved for 70 days and then refed for 6 hr, 32 hr, 4 days, and 9 days. SerDH showed a hyperbolic kinetic with a K(m) for L-serine of 77.

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Maslinic acid (2-alpha, 3-beta-dihydroxiolean-12-en-28-oic acid) is a triterpenoid compound present in fruit and leaves of Olea europaea that can be used as an additive in the diet of trout. The present work investigates the effects of maslinic acid on growth, protein-turnover rates and nucleic acid concentration in trout white muscle. Five groups of 180 trout of a mean body mass of 20 g were fed for 225 days with diets containing 0, 1, 5, 25 and 250 mg of maslinic acid per kg of diet.

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Oleuropein, the main phenolic compound of olive fruit, has important antioxidant properties that are responsible for some of the nutritional properties of fruits and the defence mechanism of leaves. Polyphenol oxidase (PPO) activity changes during fruit ripening in many plants. We studied the kinetics and molecular properties of PPO in fruits and leaves of olive (Olea europaea L.

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Maslinic acid is a triterpene present in a considerable proportion in solid residues from olive-oil production. In the present work the effects of maslinic acid on growth, protein-turnover rates and nucleic-acid concentration on liver were investigated in the rainbow trout. Five groups of 120 fish of a mean body mass of 20 g were fed for 225 days with diets containing 0, 1, 5, 25 and 250 mg of maslinic acid per kg diet.

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Blood pH controls the activity of important regulatory enzymes in the metabolism. Serine dehydratase (SerDH) transforms l-serine into pyruvate and ammonium and is involved in the regulation of gluconeogenesis from serine in the rat liver. In this work, we investigate the effect of chronic metabolic acidosis on the kinetics, specific protein level, tissue location, and mRNA levels of rat liver SerDH.

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