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Miguel A. Alvarez - One of the best experts on this subject based on the ideXlab platform.
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the dietary biogenic amines Tyramine and histamine show synergistic toxicity towards intestinal cells in culture
Food Chemistry, 2017Co-Authors: Beatriz Del Rio, Daniel M Linares, Victor Ladero, Begona Redruello, Maria Fernandez, Maria Cruz Martin, Patricia Ruasmadiedo, Miguel A. AlvarezAbstract:Tyramine and histamine are the biogenic amines (BA) most commonly found at high concentrations in food; they may even appear together at toxic concentrations. The present work examines, via real-time cell analysis, whether histamine and Tyramine show synergistic toxicity towards intestinal cell cultures. Employing a constant equipotency ratio, their interaction was examined via the combination index (CI) method of Chou & Talalay. Co-treatment with Tyramine and histamine was associated with a stronger cytotoxic effect than was treatment with either BA or on its own. Indeed, a synergistic interaction (CI<1) was observed in the range of concentrations found in foods. The results also show that histamine, at concentrations below the legal limit, increases the cytotoxicity of Tyramine at concentrations frequently reached in some foods. The synergistic cytotoxicity of Tyramine and histamine should be taken into account when establishing legal limits designed to ensure consumer safety.
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Comparative analysis of the in vitro cytotoxicity of the dietary biogenic amines Tyramine and histamine
Food Chemistry, 2016Co-Authors: Daniel M Linares, Beatriz Del Rio, M. Cruz Martin, Patricia Ruas-madiedo, Victor Ladero, Begona Redruello, Maria Fernandez, Miguel A. AlvarezAbstract:Tyramine and histamine, the most toxic biogenic amines (BA), are often found in high concentrations in certain foods. Prompted by the limited knowledge of BA toxicity, and increasing awareness of the risks associated with high intakes of dietary BA, the in vitro cytotoxicity of Tyramine and histamine was investigated. Tyramine and histamine were toxic for HT29 intestinal cell cultures at concentrations commonly found in BA-rich food, as determined by real-time cell analysis. Surprisingly, Tyramine had a stronger and more rapid cytotoxic effect than histamine. Their mode of action was also different, while Tyramine caused cell necrosis, histamine induced apoptosis. To avoid health risks, the BA content of foods should be reduced and legal limits established for Tyramine.
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Tyramine biosynthesis is transcriptionally induced at low ph and improves the fitness of enterococcus faecalis in acidic environments
Applied Microbiology and Biotechnology, 2015Co-Authors: Marta Perez, Victor Ladero, Marina Callesenriquez, Ingolf F Nes, Maria Cruz Martin, M J Fernandez, Miguel A. AlvarezAbstract:Enterococcus faecalis is a commensal bacterium of the human gut that requires the ability to pass through the stomach and therefore cope with low pH. E. faecalis has also been identified as one of the major Tyramine producers in fermented food products, where they also encounter acidic environments. In the present work, we have constructed a non-Tyramine-producing mutant to study the role of the Tyramine biosynthetic pathway, which converts tyrosine to Tyramine via amino acid decarboxylation. Wild-type strain showed higher survival in a system that mimics gastrointestinal stress, indicating that the Tyramine biosynthetic pathway has a role in acid resistance. Transcriptional analyses of the E. faecalis V583 tyrosine decarboxylase cluster showed that an acidic pH, together with substrate availability, induces its expression and therefore the production of Tyramine. The protective role of the Tyramine pathway under acidic conditions appears to be exerted through the maintenance of the cytosolic pH. Tyramine production should be considered important in the adaptability of E. faecalis to acidic environments, such as fermented dairy foods, and to survive passage through the human gastrointestinal tract.
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Role of Tyramine synthesis by food-borne enterococcus durans in adaptation to the gastrointestinal tract environment
Applied and Environmental Microbiology, 2011Co-Authors: Pilar Fernández De Palencia, Maria Luz Mohedano, Cristina Quevedo, Victor Ladero, Maria Fernandez, Miguel A. Alvarez, Paloma LopezAbstract:Biogenic amines in food constitute a human health risk. Here we report that Tyramine-producing Enterococcus durans strain IPLA655 (from cheese) was able to produce Tyramine under conditions simulating transit through the gastrointestinal tract. Activation of the Tyramine biosynthetic pathway contributed to binding and immunomodulation of enterocytes.
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qpcr for quantitative detection of Tyramine producing bacteria in dairy products
Food Research International, 2010Co-Authors: Victor Ladero, Maria Fernandez, Maria Cruz Martin, Noelia Martinez, Miguel A. AlvarezAbstract:Abstract Biogenic amines (BAs) are organic nitrogenous compounds that occur naturally in small concentrations in most living organisms, in which they have different biological functions. However, they can accumulate in foods due to the decarboxylating activity of certain bacteria. The consumption of food containing large amounts of some BAs can have toxicological consequences. Tyramine is one of the most active and common BAs found in cheeses. This article reports the design of an real-time quantitative PCR (qPCR) qPCR method for the detection and quantification of the microorganisms responsible for Tyramine production in cheeses. A good linear relationship was obtained between the quantity of Tyramine-producer DNA used in PCR reactions and the Ct (threshold cycle) value. The method was validated using 57 cheese samples in which the Tyramine concentration was analysed by HPLC. Tyramine-producing bacteria were detected in different numbers in all samples, although Tyramine itself was only detected in 56.1% of the samples. The results suggest that, independent of technological conditions such as pasteurisation or the ripening period, the presence of Tyramine-producing bacteria over a threshold limit of 10 4 cfu g −1 – easily detected by the proposed qPCR method – leads to the accumulation of Tyramine beyond recommendable limits.
Brian H Smith - One of the best experts on this subject based on the ideXlab platform.
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the biogenic amine Tyramine and its receptor amtyr1 in olfactory neuropils in the honey bee apis mellifera brain
Frontiers in Systems Neuroscience, 2017Co-Authors: Irina T Sinakevitch, Sasha M Daskalova, Brian H SmithAbstract:This paper describes the cellular sources for Tyramine and the cellular targets of Tyramine via the Tyramine Receptor 1 (AmTyr1) in the olfactory learning and memory neuropils of the honey bee brain. Clusters of approximately 160 Tyramine immunoreactive neurons are the source of Tyraminergic fibers with small varicosities in the optic lobes, antennal lobes, lateral protocerebrum, mushroom body (calyces and gamma lobes), tritocerebrum and subesophageal ganglion. Our Tyramine mapping study shows that the primary sources of Tyramine in the antennal lobe and calyx of the mushroom body are from at least two Ventral Unpaired Median neurons (VUMmd and VUMmx) with cell bodies in the subesophageal ganglion. To reveal AmTyr1 receptors in the brain, we used newly characterized anti-AmTyr1 antibodies. Immunolocalization studies in the antennal lobe with anti-AmTyr1 antibodies showed that the AmTyr1 expression pattern is mostly in the presynaptic sites of olfactory receptor neurons. In the mushroom body calyx, anti-AmTyr1 mapped the presynaptic sites of uniglomerular projection neurons located primarily in the microglomeruli of the lip and basal ring calyx area. Release of Tyramine/octopamine from VUM (md and mx) neurons in the antennal lobe and mushroom body calyx would target AmTyr1 expressed on olfactory receptor neuron and uniglomerular projection neuron presynaptic terminals. The presynaptic location of AmTyr1, its structural similarity with vertebrate alpha-2 adrenergic receptors, and previous pharmacological evidence suggests that it has an important role in the presynaptic inhibitory control of neurotransmitter release.
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the biogenic amine Tyramine and its receptor amtyr1 in olfactory neuropils in the honey bee apis mellifera brain
Frontiers in Systems Neuroscience, 2017Co-Authors: Irina T Sinakevitch, Sasha M Daskalova, Brian H SmithAbstract:This article describes the cellular sources for Tyramine and the cellular targets of Tyramine via the Tyramine Receptor 1 (AmTyr1) in the olfactory learning and memory neuropils of the honey bee brain. Clusters of approximately 160 Tyramine immunoreactive neurons are the source of Tyraminergic fibers with small varicosities in the optic lobes, antennal lobes, lateral protocerebrum, mushroom body (calyces and gamma lobes), tritocerebrum and subesophageal ganglion (SEG). Our Tyramine mapping study shows that the primary sources of Tyramine in the antennal lobe and calyx of the mushroom body are from at least two Ventral Unpaired Median neurons (VUMmd and VUMmx) with cell bodies in the SEG. To reveal AmTyr1 receptors in the brain, we used newly characterized anti-AmTyr1 antibodies. Immunolocalization studies in the antennal lobe with anti-AmTyr1 antibodies showed that the AmTyr1 expression pattern is mostly in the presynaptic sites of olfactory receptor neurons (ORNs). In the mushroom body calyx, anti-AmTyr1 mapped the presynaptic sites of uniglomerular Projection Neurons (PNs) located primarily in the microglomeruli of the lip and basal ring calyx area. Release of Tyramine/octopamine from VUM (md and mx) neurons in the antennal lobe and mushroom body calyx would target AmTyr1 expressed on ORN and uniglomerular PN presynaptic terminals. The presynaptic location of AmTyr1, its structural similarity with vertebrate alpha-2 adrenergic receptors, and previous pharmacological evidence suggests that it has an important role in the presynaptic inhibitory control of neurotransmitter release.
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octopamine and Tyramine influence the behavioral profile of locomotor activity in the honey bee apis mellifera
Journal of Insect Physiology, 2006Co-Authors: Brendon L Fussnecker, Brian H Smith, Julie A MustardAbstract:The biogenic amines octopamine and Tyramine are believed to play a number of important roles in the behavior of invertebrates including the regulation of motor function. To investigate the role of octopamine and Tyramine in locomotor behavior in honey bees, subjects were injected with a range of concentrations of octopamine, Tyramine, mianserin or yohimbine. Continuous observation of freely moving worker bees was used to examine the effects of these treatments on the amount of time honey bees spent engaged in different locomotor behaviors such as walking, grooming, fanning and flying. All treatments produced significant shifts in behavior. Decreases in time spent walking and increases in grooming or stopped behavior were observed for every drug. However, the pattern of the shift depended on drug, time after injection and concentration. Flying behavior was differentially affected with increases in flying seen in octopamine treated bees, whereas those receiving Tyramine showed a decrease in flying. Taken together, these data provide evidence that octopamine and Tyramine modulate motor function in the honey bee perhaps via interaction with central pattern generators or through effects on sensory perception.
Julie A Mustard - One of the best experts on this subject based on the ideXlab platform.
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octopamine and Tyramine influence the behavioral profile of locomotor activity in the honey bee apis mellifera
Journal of Insect Physiology, 2006Co-Authors: Brendon L Fussnecker, Brian H Smith, Julie A MustardAbstract:The biogenic amines octopamine and Tyramine are believed to play a number of important roles in the behavior of invertebrates including the regulation of motor function. To investigate the role of octopamine and Tyramine in locomotor behavior in honey bees, subjects were injected with a range of concentrations of octopamine, Tyramine, mianserin or yohimbine. Continuous observation of freely moving worker bees was used to examine the effects of these treatments on the amount of time honey bees spent engaged in different locomotor behaviors such as walking, grooming, fanning and flying. All treatments produced significant shifts in behavior. Decreases in time spent walking and increases in grooming or stopped behavior were observed for every drug. However, the pattern of the shift depended on drug, time after injection and concentration. Flying behavior was differentially affected with increases in flying seen in octopamine treated bees, whereas those receiving Tyramine showed a decrease in flying. Taken together, these data provide evidence that octopamine and Tyramine modulate motor function in the honey bee perhaps via interaction with central pattern generators or through effects on sensory perception.
Rosario Muñoz - One of the best experts on this subject based on the ideXlab platform.
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Tyramine and Phenylethylamine Biosynthesis by Food Bacteria
Critical Reviews in Food Science and Nutrition, 2012Co-Authors: Angela Marcobal, Laura Tabera, Blanca De Las Rivas, José María Landete, Rosario MuñozAbstract:Tyramine poisoning is caused by the ingestion of food containing high levels of Tyramine, a biogenic amine. Any foods containing free tyrosine are subject to Tyramine formation if poor sanitation and low quality foods are used or if the food is subject to temperature abuse or extended storage time. Tyramine is generated by decarboxylation of the tyrosine through tyrosine decarboxylase (TDC) enzymes derived from the bacteria present in the food. Bacterial TDC have been only unequivocally identified and characterized in Gram-positive bacteria, especially in lactic acid bacteria. Pyridoxal phosphate (PLP)-dependent TDC encoding genes (tyrDC) appeared flanked by a similar genetic organization in several species of lactic acid bacteria, suggesting a common origin by a single mobile genetic element. Bacterial TDC are also able to decarboxylate phenylalanine to produce phenylethylamine (PEA), another biogenic amine. The molecular knowledge of the genes involved in Tyramine production has led to the development of molecular methods for the detection of bacteria able to produce Tyramine and PEA. These rapid and simple methods could be used for the analysis of the ability to form Tyramine by bacteria in order to evaluate the potential risk of Tyramine biosynthesis in food products. © 2012 Copyright Taylor and Francis Group, LLC.
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biogenic amine production by gram positive bacteria isolated from spanish dry cured chorizo sausage treated with high pressure and kept in chilled storage
Meat Science, 2008Co-Authors: B De Las Rivas, Alfonso V. Carrascosa, Jose Antonio Curiel, Francisco Jimenezcolmenero, C Ruizcapillas, Rosario MuñozAbstract:Abstract We studied the production of biogenic amines by 200 strains of lactic acid bacteria and staphylococci isolated during chilled storage from samples of Spanish dry-cured “chorizo” sausage treated with high-pressure. The presence of biogenic amines in a decarboxylase synthetic broth was confirmed by ion-exchange chromatography. β-phenylethylamine was the biogenic amine more frequently produced (22.5%), followed by Tyramine (7.5%). In Tyramine producer-strains the presence of a tyrosine decarboxylase gene was confirmed by PCR. Among lactic acid bacteria, the production of Tyramine was mainly related to the species Lactobacillus curvatus . Most of the L. curvatus strains were also β-phenylethylamine-producers. In relation to staphylococci , Tyramine-production was mainly associated to Staphylococcus carnosus strains. The S. carnosus strains analysed in this study produced β-phenylethylamine or β-phenylethylamine and Tyramine simultaneously. RAPD-PCR results indicated that the biogenic amine-producer S. carnosus population changes along storage independently of the high-pressure treatment.
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screening of biogenic amine production by lactic acid bacteria isolated from grape must and wine
International Journal of Food Microbiology, 2003Co-Authors: Victoria M Morenoarribas, Carmen M Polo, Felisa Jorganes, Rosario MuñozAbstract:The potential to produce the biogenic amines Tyramine, histamine and putrescine, was investigated for lactic acid bacteria (LAB) of various origin, including commercial malolactic starter cultures, type strains and 78 strains isolated from Spanish grape must and wine. The presence of biogenic amines in a decarboxylase synthetic broth was determined by reverse-phase high performance liquid chromatography (RP-HPLC). Tyramine was the main amine formed by the LAB strains investigated. Leuconostoc strains were the most intensive Tyramine formers. No potential to form biogenic amines was observed in Oenococcus oeni strains. Two strains of Latobacillus buchneri were associated with putrescine formation. None of the lactic acid bacteria produced histamine. According to these in vitro results, the commercial starter bacteria analyzed did not produce histamine, Tyramine and putrescine.
Maria Fernandez - One of the best experts on this subject based on the ideXlab platform.
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the dietary biogenic amines Tyramine and histamine show synergistic toxicity towards intestinal cells in culture
Food Chemistry, 2017Co-Authors: Beatriz Del Rio, Daniel M Linares, Victor Ladero, Begona Redruello, Maria Fernandez, Maria Cruz Martin, Patricia Ruasmadiedo, Miguel A. AlvarezAbstract:Tyramine and histamine are the biogenic amines (BA) most commonly found at high concentrations in food; they may even appear together at toxic concentrations. The present work examines, via real-time cell analysis, whether histamine and Tyramine show synergistic toxicity towards intestinal cell cultures. Employing a constant equipotency ratio, their interaction was examined via the combination index (CI) method of Chou & Talalay. Co-treatment with Tyramine and histamine was associated with a stronger cytotoxic effect than was treatment with either BA or on its own. Indeed, a synergistic interaction (CI<1) was observed in the range of concentrations found in foods. The results also show that histamine, at concentrations below the legal limit, increases the cytotoxicity of Tyramine at concentrations frequently reached in some foods. The synergistic cytotoxicity of Tyramine and histamine should be taken into account when establishing legal limits designed to ensure consumer safety.
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Comparative analysis of the in vitro cytotoxicity of the dietary biogenic amines Tyramine and histamine
Food Chemistry, 2016Co-Authors: Daniel M Linares, Beatriz Del Rio, M. Cruz Martin, Patricia Ruas-madiedo, Victor Ladero, Begona Redruello, Maria Fernandez, Miguel A. AlvarezAbstract:Tyramine and histamine, the most toxic biogenic amines (BA), are often found in high concentrations in certain foods. Prompted by the limited knowledge of BA toxicity, and increasing awareness of the risks associated with high intakes of dietary BA, the in vitro cytotoxicity of Tyramine and histamine was investigated. Tyramine and histamine were toxic for HT29 intestinal cell cultures at concentrations commonly found in BA-rich food, as determined by real-time cell analysis. Surprisingly, Tyramine had a stronger and more rapid cytotoxic effect than histamine. Their mode of action was also different, while Tyramine caused cell necrosis, histamine induced apoptosis. To avoid health risks, the BA content of foods should be reduced and legal limits established for Tyramine.
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Role of Tyramine synthesis by food-borne enterococcus durans in adaptation to the gastrointestinal tract environment
Applied and Environmental Microbiology, 2011Co-Authors: Pilar Fernández De Palencia, Maria Luz Mohedano, Cristina Quevedo, Victor Ladero, Maria Fernandez, Miguel A. Alvarez, Paloma LopezAbstract:Biogenic amines in food constitute a human health risk. Here we report that Tyramine-producing Enterococcus durans strain IPLA655 (from cheese) was able to produce Tyramine under conditions simulating transit through the gastrointestinal tract. Activation of the Tyramine biosynthetic pathway contributed to binding and immunomodulation of enterocytes.
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qpcr for quantitative detection of Tyramine producing bacteria in dairy products
Food Research International, 2010Co-Authors: Victor Ladero, Maria Fernandez, Maria Cruz Martin, Noelia Martinez, Miguel A. AlvarezAbstract:Abstract Biogenic amines (BAs) are organic nitrogenous compounds that occur naturally in small concentrations in most living organisms, in which they have different biological functions. However, they can accumulate in foods due to the decarboxylating activity of certain bacteria. The consumption of food containing large amounts of some BAs can have toxicological consequences. Tyramine is one of the most active and common BAs found in cheeses. This article reports the design of an real-time quantitative PCR (qPCR) qPCR method for the detection and quantification of the microorganisms responsible for Tyramine production in cheeses. A good linear relationship was obtained between the quantity of Tyramine-producer DNA used in PCR reactions and the Ct (threshold cycle) value. The method was validated using 57 cheese samples in which the Tyramine concentration was analysed by HPLC. Tyramine-producing bacteria were detected in different numbers in all samples, although Tyramine itself was only detected in 56.1% of the samples. The results suggest that, independent of technological conditions such as pasteurisation or the ripening period, the presence of Tyramine-producing bacteria over a threshold limit of 10 4 cfu g −1 – easily detected by the proposed qPCR method – leads to the accumulation of Tyramine beyond recommendable limits.
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Factors affecting Tyramine production in Enterococcus durans IPLA 655
Applied microbiology and biotechnology, 2006Co-Authors: Maria Fernandez, Daniel M Linares, Ana Rodríguez, Miguel A. AlvarezAbstract:The decarboxylation of tyrosine by certain lactic acid bacteria leads to the undesirable presence of Tyramine in fermented foods. Tyramine is the most frequent biogenic amine found in cheese and is also commonly found in other fermented foods and beverages. The Tyramine-producing strain Enterococcus durans IPLA 655 was grown in a bioreactor under different conditions to determine the influence of carbon source, tyrosine and Tyramine concentrations, and pH on Tyramine production. The carbon source appeared to have no significant effect on the production of Tyramine. In contrast, tyrosine was necessary for Tyramine production, while the presence of Tyramine itself in the growth medium inhibited such production. pH showed by far the greatest influence on Tyramine synthesis; Tyramine was produced in the greatest quantities at pH 5.0, although this was accompanied by a reduced growth rate.
