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1.
Cell Host Microbe ; 30(6): 809-823.e6, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35439436

RESUMO

Gut microbial diurnal oscillations are important diet-dependent drivers of host circadian rhythms and metabolism ensuring optimal energy balance. However, the interplay between diet, microbes, and host factors sustaining intestinal oscillations is complex and poorly understood. Here, using a mouse model, we report the host C-type lectin antimicrobial peptide Reg3γ works with key ileal microbes to orchestrate these interactions in a bidirectional manner and does not correlate with the intestinal core circadian clock. High-fat diet is the primary driver of microbial oscillators that impair host metabolic homeostasis, resulting in arrhythmic host Reg3γ expression that secondarily drives abundance and oscillation of key gut microbes. This illustrates transkingdom coordination of biological rhythms primarily influenced by diet and reciprocal sensor-effector signals between host and microbial components, ultimately driving metabolism. Restoring the gut microbiota's capacity to sense dietary signals mediated by specific host factors such as Reg3γ could be harnessed to improve metabolic dysfunction.


Assuntos
Relógios Circadianos , Microbioma Gastrointestinal , Ritmo Circadiano , Dieta , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos
2.
PeerJ ; 6: e5166, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013837

RESUMO

Murine models are widely used to explore host-microbe interactions because of the challenges and limitations inherent to human studies. However, microbiome studies in murine models are not without their nuances. Inter-individual variations in gut microbiota are frequent even in animals housed within the same room. We therefore sought to find an efficient and effective standard operating procedure (SOP) to minimize these effects to improve consistency and reproducibility in murine microbiota studies. Mice were housed in a single room under specific-pathogen free conditions. Soiled cage bedding was routinely mixed weekly and distributed among all cages from weaning (three weeks old) until the onset of the study. Females and males were separated by sex and group-housed (up to five mice/cage) at weaning. 16S rRNA gene analyses of fecal samples showed that this protocol significantly reduced pre-study variability of gut microbiota amongst animals compared to other conventional measures used to normalize microbiota when large experimental cohorts have been required. A significant and consistent effect size was observed in gut microbiota when mice were switched from regular chow to purified diet in both sexes. However, sex and aging appeared to be independent drivers of gut microbial assemblage and should be taken into account in studies of this nature. In summary, we report a practical and effective pre-study SOP for normalizing the gut microbiome of murine cohorts that minimizes inter-individual variability and resolves co-housing problems inherent to male mice. This SOP may increase quality, rigor, and reproducibility of data acquisition and analysis.

3.
Nature ; 557(7706): 580-584, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29769727

RESUMO

Somatic mutations in tet methylcytosine dioxygenase 2 (TET2), which encodes an epigenetic modifier enzyme, drive the development of haematopoietic malignancies1-7. In both humans and mice, TET2 deficiency leads to increased self-renewal of haematopoietic stem cells with a net developmental bias towards the myeloid lineage1,4,8,9. However, pre-leukaemic myeloproliferation (PMP) occurs in only a fraction of Tet2-/- mice8,9 and humans with TET2 mutations1,3,5-7, suggesting that extrinsic non-cell-autonomous factors are required for disease onset. Here we show that bacterial translocation and increased interleukin-6 production, resulting from dysfunction of the small-intestinal barrier, are critical for the development of PMP in mice that lack Tet2 expression in haematopoietic cells. Furthermore, in symptom-free Tet2-/- mice, PMP can be induced by disrupting intestinal barrier integrity, or in response to systemic bacterial stimuli such as the toll-like receptor 2 agonist. PMP was reversed by antibiotic treatment and failed to develop in germ-free Tet2-/- mice, which illustrates the importance of microbial signals in the development of this condition. Our findings demonstrate the requirement for microbial-dependent inflammation in the development of PMP and provide a mechanistic basis for the variation in PMP penetrance observed in Tet2-/- mice. This study will prompt new lines of investigation that may profoundly affect the prevention and management of haematopoietic malignancies.


Assuntos
Doenças Assintomáticas , Fenômenos Fisiológicos Bacterianos , Proliferação de Células , Proteínas de Ligação a DNA/deficiência , Leucemia/microbiologia , Leucemia/patologia , Proteínas Proto-Oncogênicas/deficiência , Animais , Infecções Bacterianas/imunologia , Infecções Bacterianas/microbiologia , Fenômenos Fisiológicos Bacterianos/imunologia , Proteínas de Ligação a DNA/genética , Dioxigenases , Feminino , Vida Livre de Germes , Inflamação/microbiologia , Interleucina-6/imunologia , Mucosa Intestinal/metabolismo , Lactobacillus/química , Lactobacillus/citologia , Lactobacillus/imunologia , Masculino , Camundongos , Penetrância , Permeabilidade , Proteínas Proto-Oncogênicas/genética , Receptor 2 Toll-Like/agonistas
4.
Artigo em Inglês | MEDLINE | ID: mdl-29681983

RESUMO

Medications or dietary components can affect both the host and the host's gut microbiota. Changes in the microbiota may influence medication efficacy and interactions. Daikenchuto (TU-100), a herbal medication, comprised of ginger, ginseng, and Japanese pepper, is widely used in Japanese traditional Kampo medicine for intestinal motility and postoperative paralytic ileus. We previously showed in mice that consumption of TU-100 for 4 weeks changed the gut microbiota and increased bioavailability of bacterial ginsenoside metabolites. Since TU-100 is prescribed in humans for months to years, we examined the time- and sex-dependent effects of TU-100 on mouse gut microbiota. Oral administration of 1.5% TU-100 for 24 weeks caused more pronounced changes in gut microbiota in female than in male mice. Changes in both sexes largely reverted to baseline upon TU-100 withdrawal. Effects were time and dose dependent. The microbial profiles reverted to baseline within 4 weeks after withdrawal of 0.75% TU-100 but were sustained after withdrawal of 3% TU-100. In summary, dietary TU-100 changed mouse microbiota in a time-, sex-, and dose-dependent manner. These findings may be taken into consideration when determining optimizing dose for conditions of human health and disease with the consideration of differences in composition and response of the human intestinal microbiota.

5.
Cell Host Microbe ; 23(4): 458-469.e5, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29649441

RESUMO

The gut microbiota play important roles in lipid metabolism and absorption. However, the contribution of the small bowel microbiota of mammals to these diet-microbe interactions remains unclear. We determine that germ-free (GF) mice are resistant to diet-induced obesity and malabsorb fat with specifically impaired lipid digestion and absorption within the small intestine. Small bowel microbes are essential for host adaptation to dietary lipid changes by regulating gut epithelial processes involved in their digestion and absorption. In addition, GF mice conventionalized with high-fat diet-induced jejunal microbiota exhibit increased lipid absorption even when fed a low-fat diet. Conditioned media from specific bacterial strains directly upregulate lipid absorption genes in murine proximal small intestinal epithelial organoids. These findings indicate that proximal gut microbiota play key roles in host adaptability to dietary lipid variations through mechanisms involving both the digestive and absorptive phases and that these functions may contribute to conditions of over- and undernutrition.


Assuntos
Dieta/métodos , Microbioma Gastrointestinal , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Metabolismo dos Lipídeos , Animais , Camundongos
6.
Pediatr Surg Int ; 34(3): 323-330, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29196880

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a gastrointestinal disease of complex etiology resulting in devastating systemic inflammation and often death in premature newborns. We previously demonstrated that formula feeding inhibits ileal expression of heat shock protein-70 (Hsp70), a critical stress protein within the intestine. Barrier function for the premature intestine is critical. We sought to determine whether reduced Hsp70 protein expression increases neonatal intestinal permeability. METHODS: Young adult mouse colon cells (YAMC) were utilized to evaluate barrier function as well as intestine from Hsp70-/- pups (KO). Sections of intestine were analyzed by Western blot, immunohistochemistry, and real time PCR. YAMC cells were sub-lethally heated or treated with expressed milk (EM) to induce Hsp70. RESULTS: Immunostaining demonstrates co-localized Hsp70 and tight junction protein zona occludens-1 (ZO-1), suggesting physical interaction to protect tight junction function. The permeability of YAMC monolayers increases following oxidant injury and is partially blocked by Hsp70 induction either by prior heat stress or EM. RT-PCR analysis demonstrated that the Hsp70 isoforms, 70.1 and 70.3, predominate in WT pup; however, Hsp70.2 predominates in the KO pups. While Hsp70 is present in WT milk, it is not present in KO EM. Hsp70 associates with ZO-1 to maintain epithelial barrier function. CONCLUSION: Both induction of Hsp70 and exposure to EM prevent stress-induced increased permeability. Hsp70.2 is present in both WT and KO neonatal intestine, suggesting a crucial role in epithelial integrity. Induction of the Hsp70.2 isoform appears to be mediated by mother's milk. These results suggest that mother's milk feeding modulates Hsp70.2 expression and could attenuate injury leading to NEC. LEVEL OF EVIDENCE: Level III.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Mucosa Intestinal/metabolismo , Leite/metabolismo , Animais , Animais Recém-Nascidos , Citoproteção , Proteínas de Choque Térmico HSP70/genética , Camundongos , Permeabilidade , Isoformas de Proteínas , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-28971602

RESUMO

Herbal medicines and natural products used for maintenance of health or treatment of diseases have many biological effects, including altering the pharmacokinetics and metabolism of other medications. Daikenchuto (TU-100), an aqueous extract of ginger, ginseng, and Japanese green pepper fruit, is a commonly prescribed Kampo (Japanese herbal medicine) for postoperative ileus or bloating. The effects of TU-100 on drug metabolism have not been investigated. In this study, we analyzed the effect of TU-100 on expression of key drug-metabolizing enzymes (DMEs) and drug transporters (DTs) in murine liver and gastrointestinal tract using a dietary model. Liver, jejunum, and proximal colon were analyzed for phase I and II DMEs and DT mRNA expression by reverse transcription (RT) first by nonquantitative and followed by quantitative polymerase chain reaction (PCR) and protein expression. Liver, jejunum, and proximal colon expressed some identical but also unique DMEs and DTs. TU-100 increased the greatest changes in cytochrome (Cyp) 2b10 and Cyp3a11 and Mdr1a. Basal and TU-100 stimulated levels of DME and DT expression were gender-dependent, dose-dependent and reversible after cessation of TU-100 supplementation, except for some changes in the intestine. Quantitative Western blot analysis of protein extracts confirmed the quantitative PCR results.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Hidrocarboneto de Aril Hidroxilases/genética , Citocromo P-450 CYP3A/genética , Família 2 do Citocromo P450/genética , Intestinos/enzimologia , Fígado/enzimologia , Proteínas de Membrana/genética , Extratos Vegetais/efeitos adversos , Esteroide Hidroxilases/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP3A/metabolismo , Família 2 do Citocromo P450/metabolismo , Suplementos Nutricionais/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Modelos Animais , Panax , Fatores Sexuais , Esteroide Hidroxilases/metabolismo , Zanthoxylum , Zingiberaceae
8.
Sci Rep ; 7(1): 10411, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28874832

RESUMO

Recent evidence suggests the commensal microbiome regulates host immunity and influences brain function; findings that have ramifications for neurodegenerative diseases. In the context of Alzheimer's disease (AD), we previously reported that perturbations in microbial diversity induced by life-long combinatorial antibiotic (ABX) selection pressure in the APPSWE/PS1ΔE9 mouse model of amyloidosis is commensurate with reductions in amyloid-ß (Aß) plaque pathology and plaque-localised gliosis. Considering microbiota-host interactions, specifically during early post-natal development, are critical for immune- and neuro-development we now examine the impact of microbial community perturbations induced by acute ABX exposure exclusively during this period in APPSWE/PS1ΔE9 mice. We show that early post-natal (P) ABX treatment (P14-P21) results in long-term alterations of gut microbial genera (predominantly Lachnospiraceae and S24-7) and reduction in brain Aß deposition in aged APPSWE/PS1ΔE9 mice. These mice exhibit elevated levels of blood- and brain-resident Foxp3+ T-regulatory cells and display an alteration in the inflammatory milieu of the serum and cerebrospinal fluid. Finally, we confirm that plaque-localised microglia and astrocytes are reduced in ABX-exposed mice. These findings suggest that ABX-induced microbial diversity perturbations during post-natal stages of development coincide with altered host immunity mechanisms and amyloidosis in a murine model of AD.


Assuntos
Doença de Alzheimer/etiologia , Precursor de Proteína beta-Amiloide/genética , Amiloidose/genética , Antibacterianos/farmacologia , Microbiota/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/patologia , Animais , Biodiversidade , Biomarcadores , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Microbioma Gastrointestinal , Mediadores da Inflamação/metabolismo , Masculino , Metagenoma , Metagenômica/métodos , Camundongos , Camundongos Transgênicos , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/genética , Neuroimunomodulação/imunologia , Placa Amiloide/etiologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , RNA Ribossômico 16S/genética
9.
Phytother Res ; 31(1): 90-99, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27730672

RESUMO

Chemopreventative properties of traditional medicines and underlying mechanisms of action are incompletely investigated. This study demonstrates that dietary daikenchuto (TU-100), comprised of ginger, ginseng, and Japanese pepper effectively suppresses intestinal tumor development and progression in the azoxymethane (AOM) and APCmin/+ mouse models. For the AOM model, TU-100 was provided after the first of six biweekly AOM injections. Mice were sacrificed at 30 weeks. APCmin/+ mice were fed diet without or with TU-100 starting at 6 weeks, and sacrificed at 24 weeks. In both models, dietary TU-100 decreased tumor size. In APC min/+ mice, the number of small intestinal tumors was significantly decreased. In the AOM model, both TU-100 and Japanese ginseng decreased colon tumor numbers. Decreased Ki-67 and ß-catenin immunostaining and activation of numerous transduction pathways involved in tumor initiation and progression were observed. EGF receptor expression and stimulation/phosphorylation in vitro were investigated in C2BBe1 cells. TU-100, ginger, and 6-gingerol suppressed EGF receptor induced Akt activation. TU-100 and ginseng and to a lesser extent ginger or 6-gingerol inhibited EGF ERK1/2 activation. TU-100 and some of its components and metabolites of these components inhibit tumor progression in two mouse models of colon cancer by blocking downstream pathways of EGF receptor activation. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Azoximetano/química , Neoplasias do Colo/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Azoximetano/farmacologia , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Masculino , Medicina Tradicional , Camundongos , Panax , Extratos Vegetais/administração & dosagem , Zanthoxylum , Zingiberaceae
10.
Biomed Chromatogr ; 31(4)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27606833

RESUMO

After ingestion of ginseng, the bioavailability of its parent compounds is low and enteric microbiota plays an important role in parent compound biotransformation to their metabolites. Diet type can influence the enteric microbiota profile. When human subjects on different diets ingest ginseng, their different gut microbiota profiles may influence the metabolism of ginseng parent compounds. In this study, the effects of different diet type on gut microbiota metabolism of American ginseng saponins were investigated. We recruited six healthy adults who regularly consumed different diet types. These subjects received 7 days' oral American ginseng, and their biological samples were collected for LC-Q-TOF-MS analysis. We observed significant ginsenoside Rb1 (a major parent compound) and compound K (a major active metabolite) level differences in the samples from the subjects consuming different diets. Subjects on an Asian diet had much higher Rb1 levels but much lower compound K levels compared with those on a Western diet. Since compound K possesses much better cancer chemoprevention potential, our data suggested that consumers on a Western diet should obtain better cancer prevention effects with American ginseng intake compared with those on an Asian diet. Ginseng compound levels could be enhanced or reduced via gut microbiota manipulation for clinical utility.


Assuntos
Dieta , Microbioma Gastrointestinal , Panax/metabolismo , Saponinas/farmacocinética , Adulto , Cromatografia Líquida/métodos , Dieta Ocidental , Fezes/química , Microbioma Gastrointestinal/efeitos dos fármacos , Ginsenosídeos/análise , Ginsenosídeos/metabolismo , Humanos , Inativação Metabólica , Masculino , Pessoa de Meia-Idade , Saponinas/análise , Saponinas/metabolismo
11.
Sci Rep ; 6: 32094, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27561676

RESUMO

Proliferation and spatial development of colonic epithelial cells are highly regulated along the crypt vertical axis, which, when perturbed, can result in aberrant growth and carcinogenesis. In this study, two key factors were identified that have important and counterbalancing roles regulating these processes: pericrypt myofibroblast-derived Wnt-5a and the microbial metabolite butyrate. Cultured YAMC cell proliferation and heat shock protein induction were analzyed after butryate, conditioned medium with Wnt5a activity, and FrzB containing conditioned medium. In vivo studies to modulate Hsp25 employed intra-colonic wall Hsp25 encoding lentivirus. To silence Wnt-5a in vivo, intra-colonic wall Wnt-5a silencing RNA was used. Wnt-5a, secreted by stromal myofibroblasts of the lower crypt, promotes proliferation through canonical ß-catenin activation. Essential to this are two key requirements: (1) proteolytic conversion of the highly insoluble ~40 kD Wnt-5a protein to a soluble 36 mer amino acid peptide that activates epithelial ß-catenin and cellular proliferation, and (2) the simultaneous inhibition of butyrate-induced Hsp25 by Wnt-5a which is necessary to arrest the proliferative process in the upper colonic crypt. The interplay and spatial gradients of these factors insures that crypt epithelial cell proliferation and development proceed in an orderly fashion, but with sufficient plasticity to adapt to physiological perturbations including inflammation.


Assuntos
Butiratos/farmacologia , Proliferação de Células/efeitos dos fármacos , Colo/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Proteólise/efeitos dos fármacos , Proteína Wnt-5a/metabolismo , Animais , Linhagem Celular , Colo/citologia , Células Epiteliais/citologia , Proteínas de Choque Térmico/metabolismo , Mucosa Intestinal/citologia , Camundongos , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo
12.
Am J Physiol Gastrointest Liver Physiol ; 311(4): G634-G647, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27514476

RESUMO

Bifidobacterium breve and other Gram-positive gut commensal microbes protect the gastrointestinal epithelium against inflammation-induced stress. However, the mechanisms whereby these bacteria accomplish this protection are poorly understood. In this study, we examined soluble factors derived from Bifidobacterium breve and their impact on the two major protein degradation systems within intestinal epithelial cells, proteasomes and autophagy. Conditioned media from gastrointestinal Gram-positive, but not Gram-negative, bacteria activated autophagy and increased expression of the autophagy proteins Atg5 and Atg7 along with the stress response protein heat shock protein 27. Specific examination of media conditioned by the Gram-positive bacterium Bifidobacterium breve (Bb-CM) showed that this microbe produces small molecules (<3 kDa) that increase expression of the autophagy proteins Atg5 and Atg7, activate autophagy, and inhibit proteasomal enzyme activity. Upregulation of autophagy by Bb-CM was mediated through MAP kinase signaling. In vitro studies using C2BBe1 cells silenced for Atg7 and in vivo studies using mice conditionally deficient in intestinal epithelial cell Atg7 showed that Bb-CM-induced cytoprotection is dependent on autophagy. Therefore, this work demonstrates that Gram-positive bacteria modify protein degradation programs within intestinal epithelial cells to promote their survival during stress. It also reveals the therapeutic potential of soluble molecules produced by these microbes for prevention and treatment of gastrointestinal disease.


Assuntos
Autofagia/fisiologia , Mucosa Intestinal/microbiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Estresse Fisiológico/fisiologia , Animais , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Bifidobacterium breve , Linhagem Celular , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Inflamação/metabolismo , Inflamação/microbiologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Knockout , Transdução de Sinais/fisiologia
13.
Sci Rep ; 6: 30028, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27443609

RESUMO

Severe amyloidosis and plaque-localized neuro-inflammation are key pathological features of Alzheimer's disease (AD). In addition to astrocyte and microglial reactivity, emerging evidence suggests a role of gut microbiota in regulating innate immunity and influencing brain function. Here, we examine the role of the host microbiome in regulating amyloidosis in the APPSWE/PS1ΔE9 mouse model of AD. We show that prolonged shifts in gut microbial composition and diversity induced by long-term broad-spectrum combinatorial antibiotic treatment regime decreases Aß plaque deposition. We also show that levels of soluble Aß are elevated and that levels of circulating cytokine and chemokine signatures are altered in this setting. Finally, we observe attenuated plaque-localised glial reactivity in these mice and significantly altered microglial morphology. These findings suggest the gut microbiota community diversity can regulate host innate immunity mechanisms that impact Aß amyloidosis.


Assuntos
Doença de Alzheimer/fisiopatologia , Amiloidose/fisiopatologia , Microbioma Gastrointestinal/imunologia , Imunidade Inata , Inflamação/fisiopatologia , Animais , Antibacterianos/administração & dosagem , Modelos Animais de Doenças , Disbiose/induzido quimicamente , Camundongos
14.
Am J Physiol Gastrointest Liver Physiol ; 310(11): G973-88, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27079612

RESUMO

Gut dysbiosis, host genetics, and environmental triggers are implicated as causative factors in inflammatory bowel disease (IBD), yet mechanistic insights are lacking. Longitudinal analysis of ulcerative colitis (UC) patients following total colectomy with ileal anal anastomosis (IPAA) where >50% develop pouchitis offers a unique setting to examine cause vs. effect. To recapitulate human IPAA, we employed a mouse model of surgically created blind self-filling (SFL) and self-emptying (SEL) ileal loops using wild-type (WT), IL-10 knockout (KO) (IL-10), TLR4 KO (T4), and IL-10/T4 double KO mice. After 5 wk, loop histology, host gene/protein expression, and bacterial 16s rRNA profiles were examined. SFL exhibit fecal stasis due to directional motility oriented toward the loop end, whereas SEL remain empty. In WT mice, SFL, but not SEL, develop pouchlike microbial communities without accompanying active inflammation. However, in genetically susceptible IL-10-deficient mice, SFL, but not SEL, exhibit severe inflammation and mucosal transcriptomes resembling human pouchitis. The inflammation associated with IL-10 required TLR4, as animals lacking both pathways displayed little disease. Furthermore, germ-free IL-10 mice conventionalized with SFL, but not SEL, microbiota populations develop severe colitis. These data support essential roles of stasis-induced, colon-like microbiota, TLR4-mediated colonic metaplasia, and genetic susceptibility in the development of pouchitis and possibly UC. However, these factors by themselves are not sufficient. Similarities between this model and human UC/pouchitis provide opportunities for gaining insights into the mechanistic basis of IBD and for identification of targets for novel preventative and therapeutic interventions.


Assuntos
Colite Ulcerativa/etiologia , Disbiose/complicações , Motilidade Gastrointestinal , Interleucina-10/genética , Receptor 4 Toll-Like/genética , Animais , Feminino , Humanos , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Intestinos/patologia , Intestinos/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Microbiota , Receptor 4 Toll-Like/metabolismo
15.
Pharmacol Res Perspect ; 4(1): e00215, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26977303

RESUMO

Many pharmaceutical agents not only require microbial metabolism for increased bioavailability and bioactivity, but also have direct effects on gut microbial assemblage and function. We examined the possibility that these actions are not mutually exclusive and may be mutually reinforcing in ways that enhance long-term of these agents. Daikenchuto, TU-100, is a traditional Japanese medicine containing ginseng. Conversion of the ginsenoside Rb1 (Rb1) to bioactive compound K (CK) requires bacterial metabolism. Diet-incorporated TU-100 was administered to mice over a period of several weeks. T-RFLP and 454 pyrosequencing were performed to analyze the time-dependent effects on fecal microbial membership. Fecal microbial capacity to metabolize Rb1 to CK was measured by adding TU-100 or ginseng to stool samples to assess the generation of bioactive metabolites. Levels of metabolized TU-100 components in plasma and in stool samples were measured by LC-MS/MS. Cecal and stool short-chain fatty acids were measured by GC-MS. Dietary administration of TU-100 for 28 days altered the gut microbiota, increasing several bacteria genera including members of Clostridia and Lactococcus lactis. Progressive capacity of microbiota to convert Rb1 to CK was observed over the 28 days administration of dietary TU-100. Concomitantly with these changes, increases in all SCFA were observed in cecal contents and in acetate and butyrate content of the stool. Chronic consumption of dietary TU-100 promotes changes in gut microbiota enhancing metabolic capacity of TU-100 and increased bioavailability. We believe these findings have broad implications in optimizing the efficacy of natural compounds that depend on microbial bioconversion in general.

16.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1015-1016: 62-73, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26896573

RESUMO

American ginseng is a commonly consumed herbal medicine in the United States and other countries. Ginseng saponins are considered to be its active constituents. We have previously demonstrated in an in vitro experiment that human enteric microbiota metabolize ginseng parent compounds into their metabolites. In this study, we analyzed American ginseng saponins and their metabolites in human plasma, urine and feces samples by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). Six healthy male volunteers ingested 1 g of American ginseng twice a day for 7 days. On day 7, biological samples were obtained and pretreated with solid phase extraction. The ginseng constituents and their metabolites were characterized, including 5 ginseng metabolites in plasma, 10 in urine, and 26 in feces. For the plasma, urine and feces samples, the levels of ginsenoside Rb1 (a major parent compound) were 8.6, 56.8 and 57.7 ng/mL, respectively, and the levels of compound K (a major metabolite) were 58.4 ng/mL, 109.8 ng/mL and 10.06 µg/mL, respectively. It suggested that compound K had a remarkably high level in all three samples. Moreover, in human feces, ginsenoside Rk1 and Rg5, Rk3 and Rh4, Rg6 and F4 were detected as the products of dehydration. Further studies are needed to evaluate the pharmacological activities of the identified ginseng metabolites.


Assuntos
Cromatografia Líquida/métodos , Ginsenosídeos/análise , Ginsenosídeos/metabolismo , Espectrometria de Massas/métodos , Panax , Preparações de Plantas/metabolismo , Adolescente , Adulto , Fezes/química , Ginsenosídeos/química , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
17.
Cell Host Microbe ; 17(5): 681-9, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25891358

RESUMO

Circadian clocks and metabolism are inextricably intertwined, where central and hepatic circadian clocks coordinate metabolic events in response to light-dark and sleep-wake cycles. We reveal an additional key element involved in maintaining host circadian rhythms, the gut microbiome. Despite persistence of light-dark signals, germ-free mice fed low or high-fat diets exhibit markedly impaired central and hepatic circadian clock gene expression and do not gain weight compared to conventionally raised counterparts. Examination of gut microbiota in conventionally raised mice showed differential diurnal variation in microbial structure and function dependent upon dietary composition. Additionally, specific microbial metabolites induced under low- or high-fat feeding, particularly short-chain fatty acids, but not hydrogen sulfide, directly modulate circadian clock gene expression within hepatocytes. These results underscore the ability of microbially derived metabolites to regulate or modify central and hepatic circadian rhythm and host metabolic function, the latter following intake of a Westernized diet.


Assuntos
Relógios Circadianos , Dieta Hiperlipídica , Disbiose/induzido quimicamente , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Metabolismo dos Lipídeos , Animais , Peso Corporal , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Fígado/patologia , Camundongos , Dados de Sequência Molecular , Obesidade , Análise de Sequência de DNA
18.
Inflamm Bowel Dis ; 21(5): 963-72, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25738379

RESUMO

BACKGROUND: Commensal gut microbiota play an important role in regulating metabolic and inflammatory conditions. Reshaping intestinal microbiota through pharmacologic means may be a viable treatment option. We sought to delineate the functional characteristics of glucocorticoid-mediated alterations on gut microbiota and their subsequent repercussions on host mucin regulation and colonic inflammation. METHODS: Adult male C57Bl/6 mice, germ-free, Muc2-heterozygote (±), or Muc2-knockout (-/-) were injected with dexamethasone, a synthetic glucocorticoid, for 4 weeks. Fecal samples were collected for gut microbiota analysis through 16S rRNA terminal restriction fragment length polymorphism and amplicon sequencing. Intestinal mucosa was collected for mucin gene expression studies. Germ-free mice were conventionalized with gut microbes from treated and nontreated groups to determine their functional capacities in recipient hosts. RESULTS: Exposure to dexamethasone in wild-type mice led to substantial shifts in gut microbiota over a 4-week period. Furthermore, a significant downregulation of colonic Muc2 gene expression was observed after treatment. Muc2-knockout mice harbored a proinflammatory environment of gut microbes, characterized by the increase or decrease in prevalence of specific microbiota populations such as Clostridiales and Lactobacillaceae, respectively. This colitogenic phenotype was transmissible to IL10-knockout mice, a genetically susceptible model of colonic inflammatory disorders. Microbiota from donors pretreated with dexamethasone, however, ameliorated symptoms of inflammation. CONCLUSIONS: Commensal gut bacteria may be a key mediator of the anti-inflammatory effects observed in the large intestine after glucocorticoid exposure. These findings underscore the notion that intestinal microbes comprise a "microbial organ" essential for host physiology that can be targeted by therapeutic approaches to restore intestinal homeostasis.


Assuntos
Dexametasona/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Interleucina-10/fisiologia , Mucina-2/fisiologia , Animais , Anti-Inflamatórios/farmacologia , Colo/efeitos dos fármacos , Colo/microbiologia , DNA Bacteriano/genética , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Trato Gastrointestinal/microbiologia , Inflamação/etiologia , Inflamação/patologia , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética
19.
PLoS One ; 9(5): e97456, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24857966

RESUMO

The Japanese traditional medicine daikenchuto (TU-100) has anti-inflammatory activities, but the mechanisms remain incompletely understood. TU-100 includes ginger, ginseng, and Japanese pepper, each component possessing bioactive properties. The effects of TU-100 and individual components were investigated in a model of intestinal T lymphocyte activation using anti-CD3 antibody. To determine contribution of intestinal bacteria, specific pathogen free (SPF) and germ free (GF) mice were used. TU-100 or its components were delivered by diet or by gavage. Anti-CD3 antibody increased jejunal accumulation of fluid, increased TNFα, and induced intestinal epithelial apoptosis in both SPF and GF mice, which was blocked by either TU-100 or ginger, but not by ginseng or Japanese pepper. TU-100 and ginger also blocked anti-CD3-stimulated Akt and NF-κB activation. A co-culture system of colonic Caco2BBE and Jurkat-1 cells was used to examine T-lymphocyte/epithelial cells interactions. Jurkat-1 cells were stimulated with anti-CD3 to produce TNFα that activates epithelial cell NF-κB. TU-100 and ginger blocked anti-CD3 antibody activation of Akt in Jurkat cells, decreasing their TNFα production. Additionally, TU-100 and ginger alone blocked direct TNFα stimulation of Caco2BBE cells and decreased activation of caspase-3 and polyADP ribose. The present studies demonstrate a new anti-inflammatory action of TU-100 that is microbe-independent and due to its ginger component.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Enterite/tratamento farmacológico , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linfócitos T/efeitos dos fármacos , Zingiber officinale/química , Animais , Anticorpos Monoclonais/imunologia , Apoptose/efeitos dos fármacos , Complexo CD3/imunologia , Linhagem Celular Tumoral , Enterite/induzido quimicamente , Enterite/imunologia , Enterite/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Jejuno/efeitos dos fármacos , Jejuno/imunologia , Jejuno/patologia , Camundongos , Panax , Extratos Vegetais/uso terapêutico , Organismos Livres de Patógenos Específicos , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Zanthoxylum , Zingiberaceae
20.
J Vet Sci ; 15(2): 297-307, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24378587

RESUMO

This study was conducted to evaluate an adapter-modified Ussing chamber for assessment of transport physiology in endoscopically obtained duodenal biopsies from healthy cats and dogs, as well as dogs with chronic enteropathies. 17 duodenal biopsies from five cats and 51 duodenal biopsies from 13 dogs were obtained. Samples were transferred into an adapter-modified Ussing chamber and sequentially exposed to various absorbagogues and secretagogues. Overall, 78.6% of duodenal samples obtained from cats responded to at least one compound. In duodenal biopsies obtained from dogs, the rate of overall response ranged from 87.5% (healthy individuals; n = 8), to 63.6% (animals exhibiting clinical signs of gastrointestinal disease and histopathological unremarkable duodenum; n = 15), and 32.1% (animals exhibiting clinical signs of gastrointestinal diseases and moderate to severe histopathological lesions; n = 28). Detailed information regarding the magnitude and duration of the response are provided. The adapter-modified Ussing chamber enables investigation of the absorptive and secretory capacity of endoscopically obtained duodenal biopsies from cats and dogs and has the potential to become a valuable research tool. The response of samples was correlated with histopathological findings.


Assuntos
Biópsia/veterinária , Gatos/fisiologia , Cães/fisiologia , Duodenoscopia/veterinária , Duodeno/fisiologia , Animais , Doenças do Gato/fisiopatologia , Doenças do Cão/fisiopatologia , Duodenopatias/fisiopatologia , Duodeno/fisiopatologia
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