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Josep Lluís Torres - One of the best experts on this subject based on the ideXlab platform.
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Implication of gut microbiota in the physiology of rats intermittently exposed to cold and hypobaric hypoxia
PloS one, 2020Co-Authors: Sara Ramos-romero, Josep Lluís Torres, Garoa Santocildes, David Piñol-piñol, Carles Rosés, Teresa Pagés, Mercè Hereu, Susana Amézqueta, Joan Ramon Torrella, Ginés ViscorAbstract:This study examines the influence of intermittent exposure to cold, hypobaric hypoxia, and their combination, in gut microbiota and their metabolites in vivo, and explores their effects on the physiology of the host. Sprague-Dawley rats were exposed to cold (4°C), hypobaric hypoxia (462 torr), or both simultaneously, 4 h/day for 21 days. Biometrical and hematological parameters were monitored. Gut bacterial subgroups were evaluated by qPCR and short-chain fatty acids were determined by gas chromatography in caecum and feces. Cold increased brown adipose tissue, Clostridiales subpopulation and the concentration of butyric and isovaleric acids in caecum. Hypobaric hypoxia increased hemoglobin, red and white cell counts and Enterobacteriales, and reduced body and adipose tissues weights and Lactobacilliales. Cold plus hypobaric hypoxia counteracted the hypoxia-induced weight loss as well as the increase in white blood cells, while reducing the Bacteroidetes:Firmicutes ratio and normalizing the populations of Enterobacteriales and Lactobacilliales. In conclusion, intermittent cold and hypobaric hypoxia exposures by themselves modified some of the main physiological variables in vivo, while their combination kept the rats nearer to their basal status. The reduction of the Bacteroidetes:Firmicutes ratio and balanced populations of Enterobacteriales and Lactobacilliales in the gut may contribute to this effect.
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The buckwheat iminosugar D-fagomine attenuates sucrose-induced steatosis and hypertension in rats
Proceedings of the Nutrition Society, 2020Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Josep Lluís TorresAbstract:AbstractD-Fagomine (1,2 dideoxynojirimycin) is an iminosugar, a carbohydrate analogue that includes an endocyclic nitrogen instead of oxygen, that is naturally present in buckwheat and buckwheat-based foodstuffs. This study examines the long-term functional effect of d-fagomine on sucrose-induced factors of metabolic syndrome and explores possible molecular mechanisms behind its action. We evaluated Wistar Kyoto rats fed a standard diet were given a 35% sucrose (glucose/fructose) solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The variables measured were body weight and energy intake; glucose tolerance (oral glucose tolerance test); plasma leptin concentration; plasma lipid profile; the populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2-IsoPs); perigonadal fat deposition and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. We found that d-Fagomine reduced sucrose induced hypertension, urine uric acid, F2-IsoPs as markers of oxidative stress (OS), steatosis and liver DAGs (32:1, 32:2, 34:1 and 36:2) without affecting perigonadal (visceral) fat deposition or DAG levels in visceral adipose tissue. It showed a slight tendency to reduce sugar induced impaired glucose tolerance. d-Fagomine also promoted excretion of Enterobacteriales generated by the dietary intervention. We postulate that fructose increases visceral fat deposition independently of liver de novo liposynthesis and that d-fagomine attenuates steatosis and blood pressure mainly by reducing liver fructose levels. The reduction of blood pressure may be associated with an effect on uric acid synthesis while the reduced levels of selected active liver DAGs may explain the weak effect on sucrose-induced impaired glucose tolerance, which may be primarily induced by visceral fat deposition. In conclusion, the increased populations of excreted Enterobacteriales may be connected to the levels of excreted uric acid. d-Fagomine counteracts sucrose-induced steatosis and hypertension presumably by reducing the postprandial levels of fructose in the liver as a consequence of intestinal sucrase inhibition.
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The Buckwheat Iminosugar d‐Fagomine Attenuates Sucrose‐Induced Steatosis and Hypertension in Rats
Molecular nutrition & food research, 2019Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Silvia Muñoz, Isabel Medina, Bernat Miralles-pérez, Marta Romeu, Josep Lluís TorresAbstract:SCOPE This study examines the long-term functional effects of d-fagomine on sucrose-induced factors of metabolic dysfunctions and explores possible molecular mechanisms behind its action. METHODS AND RESULTS Wistar Kyoto rats are fed a 35% sucrose solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The following are recorded: body weight; energy intake; glucose tolerance; plasma leptin concentration and lipid profile; populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2 -IsoPs); perigonadal fat deposition; and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. d-Fagomine reduces sucrose-induced hypertension, urine uric acid and F2 -IsoPs (markers of oxidative stress), steatosis, and liver DAGs, without significantly affecting perigonadal fat deposition, and impaired glucose tolerance. It also promotes excretion of Enterobacteriales generated by the dietary intervention. CONCLUSION d-fagomine counteracts sucrose-induced steatosis and hypertension, presumably by reducing the postprandial levels of fructose in the liver.
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Functional Effects of the Buckwheat Iminosugar d‐Fagomine on Rats with Diet‐Induced Prediabetes
Molecular nutrition & food research, 2018Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Isabel Medina, Marta Romeu, Núria Taltavull, Gabriel Dasilva, Josep Lluís TorresAbstract:Scope The goals of this work are to test if d-fagomine, an iminosugar that reduces body weight gain, can delay the appearance of a fat-induced prediabetic state in a rat model and to explore possible mechanisms behind its functional action. Methods and results Wistar Kyoto rats were fed a high-fat diet supplemented with d-fagomine (or not, for comparison) or a standard diet (controls) for 24 weeks. The variables measured were fasting blood glucose and insulin levels; glucose tolerance; diacylglycerols as intracellular mediators of insulin resistance in adipose tissue (AT), liver, and muscle; inflammation markers (plasma IL-6 and leptin, and liver and AT histology markers); eicosanoids from arachidonic acid as lipid mediators of inflammation; and the populations of Bacteroidetes, Firmicutes, Enterobacteriales, and Bifidobacteriales in feces. It was found that d-fagomine reduces fat-induced impaired glucose tolerance, inflammation markers, and mediators (hepatic microgranulomas and lobular inflammation, plasma IL-6, prostaglandin E2 , and leukotriene B4 ) while attenuating the changes in the populations of Enterobacteriales and Bifidobacteriales. Conclusion d-Fagomine delays the development of a fat-induced prediabetic state in rats by reducing low-grade inflammation. We suggest that the anti-inflammatory effect of d-fagomine may be linked to a reduction in fat-induced overpopulation of minor gut bacteria.
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Effect of (D)-fagomine on excreted Enterobacteria and weight gain in rats fed a high-fat high-sucrose diet.
Obesity (Silver Spring Md.), 2013Co-Authors: Sara Ramos-romero, Eunice Molinar-toribio, Livia Gómez, Jara Pérez-jiménez, Marta Casado, Pere Clapés, Benjamin Piña, Josep Lluís TorresAbstract:Objective Becoming overweight has been related to elevated levels of Enterobacteriales in the gut. d-Fagomine is an iminosugar that has been shown to selectively agglutinate Enterobacteriales in vitro. The goal of this work is to establish whether d-fagomine exerts a similar effect in vivo and whether this has any downstream consequences on weight gain. Methods The rats were fed a high-fat high-sucrose diet (HFHS) supplemented with d-fagomine (or not; for comparison) or a standard diet for 5 weeks. The levels of total bacteria, Enterobacteriales and Escherichia coli were determined in fecal samples by performing quantitative real-time polymerase chain reactions on DNA. Results Whereas the total levels of bacteria were independent of the diet, rats fed HFHS (without d-fagomine) excreted significantly higher proportions of Enterobacteriales and E. coli than those fed a standard diet. The levels of Enterobacteriales and E. coli of the rats given HFHS with d-fagomine were similar to those of the rats fed a standard diet. Compared to the standard group, rats fed HFHS with d-fagomine gained significantly less weight (15.3%) than those fed HFHS (20.9%). Conclusion d-Fagomine reduces the amount of Enterobacteriales excreted by rats fed HFHS and this may help to avert becoming obese.
Sara Ramos-romero - One of the best experts on this subject based on the ideXlab platform.
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Implication of gut microbiota in the physiology of rats intermittently exposed to cold and hypobaric hypoxia
PloS one, 2020Co-Authors: Sara Ramos-romero, Josep Lluís Torres, Garoa Santocildes, David Piñol-piñol, Carles Rosés, Teresa Pagés, Mercè Hereu, Susana Amézqueta, Joan Ramon Torrella, Ginés ViscorAbstract:This study examines the influence of intermittent exposure to cold, hypobaric hypoxia, and their combination, in gut microbiota and their metabolites in vivo, and explores their effects on the physiology of the host. Sprague-Dawley rats were exposed to cold (4°C), hypobaric hypoxia (462 torr), or both simultaneously, 4 h/day for 21 days. Biometrical and hematological parameters were monitored. Gut bacterial subgroups were evaluated by qPCR and short-chain fatty acids were determined by gas chromatography in caecum and feces. Cold increased brown adipose tissue, Clostridiales subpopulation and the concentration of butyric and isovaleric acids in caecum. Hypobaric hypoxia increased hemoglobin, red and white cell counts and Enterobacteriales, and reduced body and adipose tissues weights and Lactobacilliales. Cold plus hypobaric hypoxia counteracted the hypoxia-induced weight loss as well as the increase in white blood cells, while reducing the Bacteroidetes:Firmicutes ratio and normalizing the populations of Enterobacteriales and Lactobacilliales. In conclusion, intermittent cold and hypobaric hypoxia exposures by themselves modified some of the main physiological variables in vivo, while their combination kept the rats nearer to their basal status. The reduction of the Bacteroidetes:Firmicutes ratio and balanced populations of Enterobacteriales and Lactobacilliales in the gut may contribute to this effect.
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The buckwheat iminosugar D-fagomine attenuates sucrose-induced steatosis and hypertension in rats
Proceedings of the Nutrition Society, 2020Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Josep Lluís TorresAbstract:AbstractD-Fagomine (1,2 dideoxynojirimycin) is an iminosugar, a carbohydrate analogue that includes an endocyclic nitrogen instead of oxygen, that is naturally present in buckwheat and buckwheat-based foodstuffs. This study examines the long-term functional effect of d-fagomine on sucrose-induced factors of metabolic syndrome and explores possible molecular mechanisms behind its action. We evaluated Wistar Kyoto rats fed a standard diet were given a 35% sucrose (glucose/fructose) solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The variables measured were body weight and energy intake; glucose tolerance (oral glucose tolerance test); plasma leptin concentration; plasma lipid profile; the populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2-IsoPs); perigonadal fat deposition and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. We found that d-Fagomine reduced sucrose induced hypertension, urine uric acid, F2-IsoPs as markers of oxidative stress (OS), steatosis and liver DAGs (32:1, 32:2, 34:1 and 36:2) without affecting perigonadal (visceral) fat deposition or DAG levels in visceral adipose tissue. It showed a slight tendency to reduce sugar induced impaired glucose tolerance. d-Fagomine also promoted excretion of Enterobacteriales generated by the dietary intervention. We postulate that fructose increases visceral fat deposition independently of liver de novo liposynthesis and that d-fagomine attenuates steatosis and blood pressure mainly by reducing liver fructose levels. The reduction of blood pressure may be associated with an effect on uric acid synthesis while the reduced levels of selected active liver DAGs may explain the weak effect on sucrose-induced impaired glucose tolerance, which may be primarily induced by visceral fat deposition. In conclusion, the increased populations of excreted Enterobacteriales may be connected to the levels of excreted uric acid. d-Fagomine counteracts sucrose-induced steatosis and hypertension presumably by reducing the postprandial levels of fructose in the liver as a consequence of intestinal sucrase inhibition.
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The Buckwheat Iminosugar d‐Fagomine Attenuates Sucrose‐Induced Steatosis and Hypertension in Rats
Molecular nutrition & food research, 2019Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Silvia Muñoz, Isabel Medina, Bernat Miralles-pérez, Marta Romeu, Josep Lluís TorresAbstract:SCOPE This study examines the long-term functional effects of d-fagomine on sucrose-induced factors of metabolic dysfunctions and explores possible molecular mechanisms behind its action. METHODS AND RESULTS Wistar Kyoto rats are fed a 35% sucrose solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The following are recorded: body weight; energy intake; glucose tolerance; plasma leptin concentration and lipid profile; populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2 -IsoPs); perigonadal fat deposition; and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. d-Fagomine reduces sucrose-induced hypertension, urine uric acid and F2 -IsoPs (markers of oxidative stress), steatosis, and liver DAGs, without significantly affecting perigonadal fat deposition, and impaired glucose tolerance. It also promotes excretion of Enterobacteriales generated by the dietary intervention. CONCLUSION d-fagomine counteracts sucrose-induced steatosis and hypertension, presumably by reducing the postprandial levels of fructose in the liver.
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Functional Effects of the Buckwheat Iminosugar d‐Fagomine on Rats with Diet‐Induced Prediabetes
Molecular nutrition & food research, 2018Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Isabel Medina, Marta Romeu, Núria Taltavull, Gabriel Dasilva, Josep Lluís TorresAbstract:Scope The goals of this work are to test if d-fagomine, an iminosugar that reduces body weight gain, can delay the appearance of a fat-induced prediabetic state in a rat model and to explore possible mechanisms behind its functional action. Methods and results Wistar Kyoto rats were fed a high-fat diet supplemented with d-fagomine (or not, for comparison) or a standard diet (controls) for 24 weeks. The variables measured were fasting blood glucose and insulin levels; glucose tolerance; diacylglycerols as intracellular mediators of insulin resistance in adipose tissue (AT), liver, and muscle; inflammation markers (plasma IL-6 and leptin, and liver and AT histology markers); eicosanoids from arachidonic acid as lipid mediators of inflammation; and the populations of Bacteroidetes, Firmicutes, Enterobacteriales, and Bifidobacteriales in feces. It was found that d-fagomine reduces fat-induced impaired glucose tolerance, inflammation markers, and mediators (hepatic microgranulomas and lobular inflammation, plasma IL-6, prostaglandin E2 , and leukotriene B4 ) while attenuating the changes in the populations of Enterobacteriales and Bifidobacteriales. Conclusion d-Fagomine delays the development of a fat-induced prediabetic state in rats by reducing low-grade inflammation. We suggest that the anti-inflammatory effect of d-fagomine may be linked to a reduction in fat-induced overpopulation of minor gut bacteria.
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Effect of (D)-fagomine on excreted Enterobacteria and weight gain in rats fed a high-fat high-sucrose diet.
Obesity (Silver Spring Md.), 2013Co-Authors: Sara Ramos-romero, Eunice Molinar-toribio, Livia Gómez, Jara Pérez-jiménez, Marta Casado, Pere Clapés, Benjamin Piña, Josep Lluís TorresAbstract:Objective Becoming overweight has been related to elevated levels of Enterobacteriales in the gut. d-Fagomine is an iminosugar that has been shown to selectively agglutinate Enterobacteriales in vitro. The goal of this work is to establish whether d-fagomine exerts a similar effect in vivo and whether this has any downstream consequences on weight gain. Methods The rats were fed a high-fat high-sucrose diet (HFHS) supplemented with d-fagomine (or not; for comparison) or a standard diet for 5 weeks. The levels of total bacteria, Enterobacteriales and Escherichia coli were determined in fecal samples by performing quantitative real-time polymerase chain reactions on DNA. Results Whereas the total levels of bacteria were independent of the diet, rats fed HFHS (without d-fagomine) excreted significantly higher proportions of Enterobacteriales and E. coli than those fed a standard diet. The levels of Enterobacteriales and E. coli of the rats given HFHS with d-fagomine were similar to those of the rats fed a standard diet. Compared to the standard group, rats fed HFHS with d-fagomine gained significantly less weight (15.3%) than those fed HFHS (20.9%). Conclusion d-Fagomine reduces the amount of Enterobacteriales excreted by rats fed HFHS and this may help to avert becoming obese.
Radhey S. Gupta - One of the best experts on this subject based on the ideXlab platform.
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genome based phylogeny and taxonomy of the Enterobacteriales proposal for enterobacterales ord nov divided into the families enterobacteriaceae erwiniaceae fam nov pectobacteriaceae fam nov yersiniaceae fam nov hafniaceae fam nov morganellaceae fam n
International Journal of Systematic and Evolutionary Microbiology, 2016Co-Authors: Mobolaji Adeolu, Seema Alnajar, Sohail Naushad, Radhey S. GuptaAbstract:Understanding of the phylogeny and interrelationships of the genera within the order ‘ Enterobacteriales ’ has proven difficult using the 16S rRNA gene and other single-gene or limited multi-gene approaches. In this work, we have completed comprehensive comparative genomic analyses of the members of the order ‘ Enterobacteriales ’ which includes phylogenetic reconstructions based on 1548 core proteins, 53 ribosomal proteins and four multilocus sequence analysis proteins, as well as examining the overall genome similarity amongst the members of this order. The results of these analyses all support the existence of seven distinct monophyletic groups of genera within the order ‘ Enterobacteriales ’. In parallel, our analyses of protein sequences from the ‘ Enterobacteriales ’ genomes have identified numerous molecular characteristics in the forms of conserved signature insertions/deletions, which are specifically shared by the members of the identified clades and independently support their monophyly and distinctness. Many of these groupings, either in part or in whole, have been recognized in previous evolutionary studies, but have not been consistently resolved as monophyletic entities in 16S rRNA gene trees. The work presented here represents the first comprehensive, genome-scale taxonomic analysis of the entirety of the order ‘ Enterobacteriales ’. On the basis of phylogenetic analyses and the numerous identified conserved molecular characteristics, which clearly distinguish members of the order ‘ Enterobacteriales ’ and the seven reported clades within this order, a proposal is made here for the order Enterobacterales ord. nov. which consists of seven families: Enterobacteriaceae , Erwiniaceae fam. nov., Pectobacteriaceae fam. nov., Yersiniaceae fam. nov., Hafniaceae fam. nov., Morganellaceae fam. nov., and Budviciaceae fam. nov.
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Phylogenomics and protein signatures elucidating the evolutionary relationships among the Gammaproteobacteria
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2009Co-Authors: Beile Gao, Ritu Mohan, Radhey S. GuptaAbstract:The class Gammaproteobacteria, which forms one of the largest groups within bacteria, is currently distinguished from other bacteria solely on the basis of its branching in phylogenetic trees. No molecular or biochemical characteristic is known that is unique to the class Gammaproteobacteria or its different subgroups (orders). The relationship among different orders of gammaproteobacteria is also not clear. In this study, we present detailed phylogenomic and comparative genomic analyses on gammaproteobacteria that clarify some of these issues. Phylogenetic trees based on concatenated sequences for 13 and 36 universally distributed proteins were constructed for 45 members of the class Gammaproteobacteria covering 13 of its 14 orders. In these trees, species from a number of the subgroups formed distinct clades and their relative branching order was indicated as follows (from the most recent to the earliest diverging): Enterobacteriales >Pasteurellales >Vibrionales, Aeromonadales >Alteromonadales >Oceanospirillales, Pseudomonadales >Chromatiales, Legionellales, Methylococcales, Xanthomonadales, Cardiobacteriales, Thiotrichales. Four conserved indels in four widely distributed proteins that are specific for gammaproteobacteria are also described. A 2 aa deletion in 5′-phosphoribosyl-5-aminoimidazole-4-carboxamide transformylase (AICAR transformylase; PurH) was a distinctive characteristic of all gammaproteobacteria (except Francisella tularensis). Two other conserved indels (a 4 aa deletion in RNA polymerase β-subunit and a 1 aa deletion in ribosomal protein L16) were found uniquely in various species of the orders Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales and Alteromonadales, but were not found in other gammaproteobacteria. Lastly, a 2 aa deletion in leucyl-tRNA synthetase was commonly present in the above orders of the class Gammaproteobacteria and also in some members of the order Oceanospirillales. The presence of the conserved indels in these gammaproteobacterial orders indicates that species from these orders shared a common ancestor that was separate from other bacteria, a suggestion that is supported by phylogenetic studies. Systematic blastp searches were also conducted on various open reading frames (ORFs) in the genome of Escherichia coli K-12. These analyses identified 75 proteins that were unique to most members of the class Gammaproteobacteria or were restricted to species from some of its main orders (Enterobacteriales; Enterobacteriales and Pasteurellales; Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales and Alteromonadales; and the Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales, Alteromonadales, Oceanospirillales and Pseudomonadales etc.). The genes for these proteins have evolved at various stages during the evolution of gammaproteobacteria and their species distribution pattern, in conjunction with other results presented here, provide valuable information regarding the evolutionary relationships among these bacteria.
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Phylogenomics and protein signatures elucidating the evolutionary relationships among the Gammaproteobacteria.
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Beile Gao, Ritu Mohan, Radhey S. GuptaAbstract:The class Gammaproteobacteria, which forms one of the largest groups within bacteria, is currently distinguished from other bacteria solely on the basis of its branching in phylogenetic trees. No molecular or biochemical characteristic is known that is unique to the class Gammaproteobacteria or its different subgroups (orders). The relationship among different orders of gammaproteobacteria is also not clear. In this study, we present detailed phylogenomic and comparative genomic analyses on gammaproteobacteria that clarify some of these issues. Phylogenetic trees based on concatenated sequences for 13 and 36 universally distributed proteins were constructed for 45 members of the class Gammaproteobacteria covering 13 of its 14 orders. In these trees, species from a number of the subgroups formed distinct clades and their relative branching order was indicated as follows (from the most recent to the earliest diverging): Enterobacteriales >Pasteurellales >Vibrionales, Aeromonadales >Alteromonadales >Oceanospirillales, Pseudomonadales >Chromatiales, Legionellales, Methylococcales, Xanthomonadales, Cardiobacteriales, Thiotrichales. Four conserved indels in four widely distributed proteins that are specific for gammaproteobacteria are also described. A 2 aa deletion in 5'-phosphoribosyl-5-aminoimidazole-4-carboxamide transformylase (AICAR transformylase; PurH) was a distinctive characteristic of all gammaproteobacteria (except Francisella tularensis). Two other conserved indels (a 4 aa deletion in RNA polymerase beta-subunit and a 1 aa deletion in ribosomal protein L16) were found uniquely in various species of the orders Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales and Alteromonadales, but were not found in other gammaproteobacteria. Lastly, a 2 aa deletion in leucyl-tRNA synthetase was commonly present in the above orders of the class Gammaproteobacteria and also in some members of the order Oceanospirillales. The presence of the conserved indels in these gammaproteobacterial orders indicates that species from these orders shared a common ancestor that was separate from other bacteria, a suggestion that is supported by phylogenetic studies. Systematic blastp searches were also conducted on various open reading frames (ORFs) in the genome of Escherichia coli K-12. These analyses identified 75 proteins that were unique to most members of the class Gammaproteobacteria or were restricted to species from some of its main orders (Enterobacteriales; Enterobacteriales and Pasteurellales; Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales and Alteromonadales; and the Enterobacteriales, Pasteurellales, Vibrionales, Aeromonadales, Alteromonadales, Oceanospirillales and Pseudomonadales etc.). The genes for these proteins have evolved at various stages during the evolution of gammaproteobacteria and their species distribution pattern, in conjunction with other results presented here, provide valuable information regarding the evolutionary relationships among these bacteria.
Ellen Ariel - One of the best experts on this subject based on the ideXlab platform.
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evidence of antibiotic resistance in Enterobacteriales isolated from green sea turtles chelonia mydas on the great barrier reef
Marine Pollution Bulletin, 2017Co-Authors: Md Shamim Ahasan, Jacqueline Picard, Lisa Elliott, Robert T. Kinobe, Leigh Owens, Ellen ArielAbstract:This study investigated Enterobacteriales and their antimicrobial resistance in green sea turtles captured adjacent to the central Great Barrier Reef (GBR) and proximate to urban development. Cloacal swabs were taken from 73 green turtles between 2015 and 2016. A total of 154 out of 341 Gram-negative bacterial isolates were identified as Enterobacteriales that represent 16 different species from 9 different genera. The dominant isolates were Citrobacter (30.52%), Edwardsiella (21.43%) and Escherichia (12.34%). The resistance against 12 antibiotics belonging to 6 different classes was determined. The isolates showed highest resistance to β-lactam antibiotics (78.57%) followed by quinolone (50%) and tetracycline classes (46.1%). Approximately one-third (37.7%) of the isolates identified exhibited multidrug-resistance. Isolates recovered from rehabilitated turtles were significantly multidrug resistant (p<0.009) compared to isolates from other study sites. These results provide baseline information on antimicrobial resistance while revealing gaps for further research to evaluate the level of pollution in the GBR.
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Evidence of antibiotic resistance in Enterobacteriales isolated from green sea turtles, Chelonia mydas on the Great Barrier Reef
Marine pollution bulletin, 2017Co-Authors: Shamim Ahasan, Jacqueline Picard, Lisa Elliott, Robert T. Kinobe, Leigh Owens, Ellen ArielAbstract:This study investigated Enterobacteriales and their antimicrobial resistance in green sea turtles captured adjacent to the central Great Barrier Reef (GBR) and proximate to urban development. Cloacal swabs were taken from 73 green turtles between 2015 and 2016. A total of 154 out of 341 Gram-negative bacterial isolates were identified as Enterobacteriales that represent 16 different species from 9 different genera. The dominant isolates were Citrobacter (30.52%), Edwardsiella (21.43%) and Escherichia (12.34%). The resistance against 12 antibiotics belonging to 6 different classes was determined. The isolates showed highest resistance to β-lactam antibiotics (78.57%) followed by quinolone (50%) and tetracycline classes (46.1%). Approximately one-third (37.7%) of the isolates identified exhibited multidrug-resistance. Isolates recovered from rehabilitated turtles were significantly multidrug resistant (p
Susana Amézqueta - One of the best experts on this subject based on the ideXlab platform.
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Implication of gut microbiota in the physiology of rats intermittently exposed to cold and hypobaric hypoxia
PloS one, 2020Co-Authors: Sara Ramos-romero, Josep Lluís Torres, Garoa Santocildes, David Piñol-piñol, Carles Rosés, Teresa Pagés, Mercè Hereu, Susana Amézqueta, Joan Ramon Torrella, Ginés ViscorAbstract:This study examines the influence of intermittent exposure to cold, hypobaric hypoxia, and their combination, in gut microbiota and their metabolites in vivo, and explores their effects on the physiology of the host. Sprague-Dawley rats were exposed to cold (4°C), hypobaric hypoxia (462 torr), or both simultaneously, 4 h/day for 21 days. Biometrical and hematological parameters were monitored. Gut bacterial subgroups were evaluated by qPCR and short-chain fatty acids were determined by gas chromatography in caecum and feces. Cold increased brown adipose tissue, Clostridiales subpopulation and the concentration of butyric and isovaleric acids in caecum. Hypobaric hypoxia increased hemoglobin, red and white cell counts and Enterobacteriales, and reduced body and adipose tissues weights and Lactobacilliales. Cold plus hypobaric hypoxia counteracted the hypoxia-induced weight loss as well as the increase in white blood cells, while reducing the Bacteroidetes:Firmicutes ratio and normalizing the populations of Enterobacteriales and Lactobacilliales. In conclusion, intermittent cold and hypobaric hypoxia exposures by themselves modified some of the main physiological variables in vivo, while their combination kept the rats nearer to their basal status. The reduction of the Bacteroidetes:Firmicutes ratio and balanced populations of Enterobacteriales and Lactobacilliales in the gut may contribute to this effect.
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The buckwheat iminosugar D-fagomine attenuates sucrose-induced steatosis and hypertension in rats
Proceedings of the Nutrition Society, 2020Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Josep Lluís TorresAbstract:AbstractD-Fagomine (1,2 dideoxynojirimycin) is an iminosugar, a carbohydrate analogue that includes an endocyclic nitrogen instead of oxygen, that is naturally present in buckwheat and buckwheat-based foodstuffs. This study examines the long-term functional effect of d-fagomine on sucrose-induced factors of metabolic syndrome and explores possible molecular mechanisms behind its action. We evaluated Wistar Kyoto rats fed a standard diet were given a 35% sucrose (glucose/fructose) solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The variables measured were body weight and energy intake; glucose tolerance (oral glucose tolerance test); plasma leptin concentration; plasma lipid profile; the populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2-IsoPs); perigonadal fat deposition and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. We found that d-Fagomine reduced sucrose induced hypertension, urine uric acid, F2-IsoPs as markers of oxidative stress (OS), steatosis and liver DAGs (32:1, 32:2, 34:1 and 36:2) without affecting perigonadal (visceral) fat deposition or DAG levels in visceral adipose tissue. It showed a slight tendency to reduce sugar induced impaired glucose tolerance. d-Fagomine also promoted excretion of Enterobacteriales generated by the dietary intervention. We postulate that fructose increases visceral fat deposition independently of liver de novo liposynthesis and that d-fagomine attenuates steatosis and blood pressure mainly by reducing liver fructose levels. The reduction of blood pressure may be associated with an effect on uric acid synthesis while the reduced levels of selected active liver DAGs may explain the weak effect on sucrose-induced impaired glucose tolerance, which may be primarily induced by visceral fat deposition. In conclusion, the increased populations of excreted Enterobacteriales may be connected to the levels of excreted uric acid. d-Fagomine counteracts sucrose-induced steatosis and hypertension presumably by reducing the postprandial levels of fructose in the liver as a consequence of intestinal sucrase inhibition.
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The Buckwheat Iminosugar d‐Fagomine Attenuates Sucrose‐Induced Steatosis and Hypertension in Rats
Molecular nutrition & food research, 2019Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Silvia Muñoz, Isabel Medina, Bernat Miralles-pérez, Marta Romeu, Josep Lluís TorresAbstract:SCOPE This study examines the long-term functional effects of d-fagomine on sucrose-induced factors of metabolic dysfunctions and explores possible molecular mechanisms behind its action. METHODS AND RESULTS Wistar Kyoto rats are fed a 35% sucrose solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The following are recorded: body weight; energy intake; glucose tolerance; plasma leptin concentration and lipid profile; populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, Enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2 -IsoPs); perigonadal fat deposition; and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. d-Fagomine reduces sucrose-induced hypertension, urine uric acid and F2 -IsoPs (markers of oxidative stress), steatosis, and liver DAGs, without significantly affecting perigonadal fat deposition, and impaired glucose tolerance. It also promotes excretion of Enterobacteriales generated by the dietary intervention. CONCLUSION d-fagomine counteracts sucrose-induced steatosis and hypertension, presumably by reducing the postprandial levels of fructose in the liver.
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Functional Effects of the Buckwheat Iminosugar d‐Fagomine on Rats with Diet‐Induced Prediabetes
Molecular nutrition & food research, 2018Co-Authors: Sara Ramos-romero, Mercè Hereu, Susana Amézqueta, Lidia Atienza, Josefina Casas, Isabel Medina, Marta Romeu, Núria Taltavull, Gabriel Dasilva, Josep Lluís TorresAbstract:Scope The goals of this work are to test if d-fagomine, an iminosugar that reduces body weight gain, can delay the appearance of a fat-induced prediabetic state in a rat model and to explore possible mechanisms behind its functional action. Methods and results Wistar Kyoto rats were fed a high-fat diet supplemented with d-fagomine (or not, for comparison) or a standard diet (controls) for 24 weeks. The variables measured were fasting blood glucose and insulin levels; glucose tolerance; diacylglycerols as intracellular mediators of insulin resistance in adipose tissue (AT), liver, and muscle; inflammation markers (plasma IL-6 and leptin, and liver and AT histology markers); eicosanoids from arachidonic acid as lipid mediators of inflammation; and the populations of Bacteroidetes, Firmicutes, Enterobacteriales, and Bifidobacteriales in feces. It was found that d-fagomine reduces fat-induced impaired glucose tolerance, inflammation markers, and mediators (hepatic microgranulomas and lobular inflammation, plasma IL-6, prostaglandin E2 , and leukotriene B4 ) while attenuating the changes in the populations of Enterobacteriales and Bifidobacteriales. Conclusion d-Fagomine delays the development of a fat-induced prediabetic state in rats by reducing low-grade inflammation. We suggest that the anti-inflammatory effect of d-fagomine may be linked to a reduction in fat-induced overpopulation of minor gut bacteria.