Antibiotics are usually prescribed to cure infections but they also have significant modulatory effects on the gut microbiota. Several alterations of the intestinal bacterial community have been reported during antibi...Antibiotics are usually prescribed to cure infections but they also have significant modulatory effects on the gut microbiota. Several alterations of the intestinal bacterial community have been reported during antibiotic treatment, including the reduction of beneficial bacteria as well as of microbial alpha-diversity. Although after the discontinuation of antibiotic therapies it has been observed a trend towards the restoration of the original condition, the new steady state is different from the previous one, as if antibiotics induced some kind of irreversible perturbation of the gut microbial community. The poorly absorbed antibiotic rifaximin seem to be different from the other antibiotics, because it exerts non-traditional effects additional to the bactericidal/bacteriostatic activity on the gut microbiota. Rifaximin is able to reduce bacterial virulence and translocation, has anti-inflammatory properties and has been demonstrated to positively modulate the gut microbial composition. Animal models, culture studies and metagenomic analyses have demonstrated an increase in Bifidobacterium, Faecalibacterium prausnitzii and Lactobacillus abundance after rifaximin treatment, probably consequent to the induction of bacterial resistance, with no major change in the overall gut microbiota composition. Antibiotics are therefore modulators of the symbiotic relationship between the host and the gut microbiota. Specific antibiotics, such as rifaximin, can also induce eubiotic changes in the intestinal ecosystem; this additional property may represent a therapeutic advantage in specific clinical settings.展开更多
Objective To investigate the metabolic routes and metabolites of Rehmannia glutinosa and Cornus officinalis herb pair produced by gut microbiome from rats.Methods A rapid and sensitive ultra-performance liquid chromat...Objective To investigate the metabolic routes and metabolites of Rehmannia glutinosa and Cornus officinalis herb pair produced by gut microbiome from rats.Methods A rapid and sensitive ultra-performance liquid chromatography/quadrupole-time-offlight mass spectrometry(UPLC-Q-TOF/MS) technique combined with Metabolynx?software was established and successfully applied to identify the metabolites of the main bioactive components in the herb pair extract by rat intestinal bacteria.Results Four parent compounds(loganin,morroniside,catalpol,and acteoside) and their eight corresponding metabolites were detected and tentatively identified by the characteristics of their protonated ions.Hydrogenated and demethylated loganetin,dehydroxylated morronisid aglycone,caffeic acid,and its methylated product were the main metabolites.These metabolites suggested that the glycosides were firstly hydrolyzed to their aglycones by hydrolytic enzymes of the enteric microbial flora and subsequently to the other metabolites through hydrogenation,(de)-methylation,and de-hydroxylation.Conclusion The results may be helpful for the further investigation of the pharmacokinetic study of R.glutinosa and C.officinalis herb pair in vivo.展开更多
Poliumoside is representative of phenylethanoid glycosides, which are widely found in many plants. Poliumoside is also regarded as the main active component of Callicarpa kwangtungensis Chun(CK), though its oral bioav...Poliumoside is representative of phenylethanoid glycosides, which are widely found in many plants. Poliumoside is also regarded as the main active component of Callicarpa kwangtungensis Chun(CK), though its oral bioavailability in rat is extremely low(0.69%) and its in vivo and in vitro metabolism has not yet been systematically investigated. In the present study, an ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry(UPLC/Q-TOF-MS) method was employed to identify the metabolites and investigate the metabolic pathways of poliumoside in rat after oral administration 1.5 g·kg–1 of poliumoside. As a result, a total of 34 metabolites(30 from urine, 17 from plasma, and 4 from bile) and 9 possible metabolic pathways(rearrangment, reduction, hydration, hydrolyzation, dehydration, methylation, hydroxylation, acetylation, and sulfation) were proposed in vivo. The main metabolite, acteoside, was quantified after incubated with rat intestinal bacteria in vitro. In conclusion, the present study systematically explored the metabolites of poliumoside in vivo and in vitro, proposing metabolic pathways that may be significant for further metabolic studies of poliumoside.展开更多
文摘Antibiotics are usually prescribed to cure infections but they also have significant modulatory effects on the gut microbiota. Several alterations of the intestinal bacterial community have been reported during antibiotic treatment, including the reduction of beneficial bacteria as well as of microbial alpha-diversity. Although after the discontinuation of antibiotic therapies it has been observed a trend towards the restoration of the original condition, the new steady state is different from the previous one, as if antibiotics induced some kind of irreversible perturbation of the gut microbial community. The poorly absorbed antibiotic rifaximin seem to be different from the other antibiotics, because it exerts non-traditional effects additional to the bactericidal/bacteriostatic activity on the gut microbiota. Rifaximin is able to reduce bacterial virulence and translocation, has anti-inflammatory properties and has been demonstrated to positively modulate the gut microbial composition. Animal models, culture studies and metagenomic analyses have demonstrated an increase in Bifidobacterium, Faecalibacterium prausnitzii and Lactobacillus abundance after rifaximin treatment, probably consequent to the induction of bacterial resistance, with no major change in the overall gut microbiota composition. Antibiotics are therefore modulators of the symbiotic relationship between the host and the gut microbiota. Specific antibiotics, such as rifaximin, can also induce eubiotic changes in the intestinal ecosystem; this additional property may represent a therapeutic advantage in specific clinical settings.
基金National Natural Science Foundation of China(No.81072996,81102743)Priority Academic Programs Development of Jiangsu Higher Education Institutions(PAPD)
文摘Objective To investigate the metabolic routes and metabolites of Rehmannia glutinosa and Cornus officinalis herb pair produced by gut microbiome from rats.Methods A rapid and sensitive ultra-performance liquid chromatography/quadrupole-time-offlight mass spectrometry(UPLC-Q-TOF/MS) technique combined with Metabolynx?software was established and successfully applied to identify the metabolites of the main bioactive components in the herb pair extract by rat intestinal bacteria.Results Four parent compounds(loganin,morroniside,catalpol,and acteoside) and their eight corresponding metabolites were detected and tentatively identified by the characteristics of their protonated ions.Hydrogenated and demethylated loganetin,dehydroxylated morronisid aglycone,caffeic acid,and its methylated product were the main metabolites.These metabolites suggested that the glycosides were firstly hydrolyzed to their aglycones by hydrolytic enzymes of the enteric microbial flora and subsequently to the other metabolites through hydrogenation,(de)-methylation,and de-hydroxylation.Conclusion The results may be helpful for the further investigation of the pharmacokinetic study of R.glutinosa and C.officinalis herb pair in vivo.
文摘Poliumoside is representative of phenylethanoid glycosides, which are widely found in many plants. Poliumoside is also regarded as the main active component of Callicarpa kwangtungensis Chun(CK), though its oral bioavailability in rat is extremely low(0.69%) and its in vivo and in vitro metabolism has not yet been systematically investigated. In the present study, an ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry(UPLC/Q-TOF-MS) method was employed to identify the metabolites and investigate the metabolic pathways of poliumoside in rat after oral administration 1.5 g·kg–1 of poliumoside. As a result, a total of 34 metabolites(30 from urine, 17 from plasma, and 4 from bile) and 9 possible metabolic pathways(rearrangment, reduction, hydration, hydrolyzation, dehydration, methylation, hydroxylation, acetylation, and sulfation) were proposed in vivo. The main metabolite, acteoside, was quantified after incubated with rat intestinal bacteria in vitro. In conclusion, the present study systematically explored the metabolites of poliumoside in vivo and in vitro, proposing metabolic pathways that may be significant for further metabolic studies of poliumoside.
