Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.249
Filtrar
1.
J Vis Exp ; (181)2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35377361

RESUMO

Gastrointestinal (GI) motility is critical for normal digestion and absorption. In the small bowel, which absorbs nutrients, motility optimizes digestion and absorption. For this reason, some of the motility patterns in the small bowel include segmentation for mixing of luminal contents and peristalsis for their propulsion. Physical properties of luminal contents modulate the patterns of small bowel motility. The mechanical stimulation of GI mechanosensory circuits by transiting luminal contents and underlying gut motility initiate and modulate complex GI motor patterns. Yet, the mechanosensory mechanisms that drive this process remain poorly understood. This is primarily due to a lack of tools to dissect how the small bowel handles materials of different physical properties. To study how the small bowel handles particulates of varying sizes, we have modified an established in vivo method to determine small bowel transit. We gavage live mice with fluorescent liquid or tiny fluorescent beads. After 30 minutes, we dissect out the bowels to image the distribution of fluorescent contents across the entirety of the GI tract. In addition to high-resolution measurements of the geometric center, we use variable size binning and spectral analysis to determine how different materials affect small bowel transit. We have explored how a recently discovered "gut touch" mechanism affects small bowel motility using this approach.


Assuntos
Motilidade Gastrointestinal , Intestino Delgado , Abdome , Animais , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Camundongos , Tato
2.
STAR Protoc ; 3(1): 101157, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35146454

RESUMO

The myenteric plexus is located between the longitudinal and circular layers of muscularis externa in the gastrointestinal tract. It contains a large network of enteric neurons that form the enteric nervous system (ENS) and control intestinal functions, such as motility and nutrient sensing. This protocol describes the method for physical separation (peeling) of muscularis and submucosal layers of the mouse intestine. Subsequently, the intestinal layers are then processed for flow cytometry and/or immunofluorescence analysis. For complete details on the use and execution of this profile, please refer to Ahrends et al. (2021).


Assuntos
Trato Gastrointestinal/fisiologia , Plexo Mientérico/citologia , Plexo Submucoso/citologia , Animais , Citometria de Fluxo/métodos , Imunofluorescência , Camundongos , Camundongos Endogâmicos C57BL
3.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216133

RESUMO

Compelling evidence is building for the involvement of the complex, bidirectional communication axis between the gastrointestinal tract and the brain in neuropsychiatric disorders such as depression. With depression projected to be the number one health concern by 2030 and its pathophysiology yet to be fully elucidated, a comprehensive understanding of the interactions between environmental factors, such as stress and diet, with the neurobiology of depression is needed. In this review, the latest research on the effects of stress on the bidirectional connections between the brain and the gut across the most widely used animal models of stress and depression is summarised, followed by comparisons of the diversity and composition of the gut microbiota across animal models of stress and depression with possible implications for the gut-brain axis and the impact of dietary changes on these. The composition of the gut microbiota was consistently altered across the animal models investigated, although differences between each of the studies and models existed. Chronic stressors appeared to have negative effects on both brain and gut health, while supplementation with prebiotics and/or probiotics show promise in alleviating depression pathophysiology.


Assuntos
Encéfalo/fisiologia , Depressão/fisiopatologia , Microbioma Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Dieta , Humanos , Modelos Animais
4.
Sci Rep ; 12(1): 2655, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173256

RESUMO

Humans have long-used mushrooms as food and medicine, but digestion and colonic fermentation of most mushrooms, including Lentinus squarrosulus is markedly unknown. Here, nutritional profile, digestion and colonic fermentation of L. squarrosulus powder (LP) were determined. The powder contained mainly carbohydrate and protein. SEM and F-TIR analysis of the resistant hydrolysate (RH) revealed that the structure and ratio of carbohydrate and protein components were altered, and released known immunomodulation agents; beta-glucans and mannose. Both LP and RH promoted selected probiotic bacteria, especially Bifidobacterium strains. Using fecal microbiota of five volunteers (V1, V2, V3, V4 and V5), RH stimulated the microbiota of all used volunteers, via decreasing the ratio of Firmicutes/Bacteroidetes ranging from 1.3 to 8.2 times. Also, RH increased the relative abundance of vital immunomodulators; Bacteroides, Bifidobacterium, Clostridium cluster XIVa and IV, and Sutterella. Additionally, RH fermentation enriched the content of branch-chain fatty acids (BCFA) and short-chain fatty acids (SCFA), indicating protein and carbohydrate usage. Notably, propionic and butyric acids were abundant in V1, V2 and V3, while in V4 and V5, acetic and butyric acids were most enriched. Suggesting L. squarrosulus as functional mushroom to improve health and prevent diseases by enhancing gut health.


Assuntos
Digestão/fisiologia , Fezes/microbiologia , Alimento Funcional , Microbioma Gastrointestinal , Trato Gastrointestinal/fisiologia , Lentinula , Carboidratos/análise , Ácidos Graxos/análise , Fermentação , Alimento Funcional/análise , Humanos , Técnicas In Vitro , Lentinula/química , Pós , Proteínas/análise
5.
Pharmacol Res Perspect ; 10(2): e00900, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35191209

RESUMO

The gastrointestinal (GI) hormone motilin helps control human stomach movements during hunger and promotes hunger. Although widely present among mammals, it is generally accepted that in rodents the genes for motilin and/or its receptor have undergone pseudonymization, so exogenous motilin cannot function. However, several publications describe functions of low concentrations of motilin, usually within the GI tract and CNS of mice, rats, and guinea pigs. These animals were from institute-held stocks, simply described with stock names (e.g., "Sprague-Dawley") or were inbred strains. It is speculated that variation in source/type of animal introduces genetic variations to promote motilin-sensitive pathways. Perhaps, in some populations, motilin receptors exist, or a different functionally-active receptor has a good affinity for motilin (indicating evolutionary pressures to retain motilin functions). The ghrelin receptor has the closest sequence homology, yet in non-rodents the receptors have a poor affinity for each other's cognate ligand. In rodents, ghrelin may substitute for certain GI functions of motilin, but no good evidence suggests rodent ghrelin receptors are highly responsive to motilin. It remains unknown if motilin has functional relationships with additional bioactive molecules formed from the ghrelin and motilin genes, or if a 5-TM motilin receptor has influence in rodents (e.g., to dimerize with GPCRs and create different pharmacological profiles). Is the absence/presence of responses to motilin in rodents' characteristic for systems undergoing gene pseudonymization? What are the consequences of rodent supplier-dependent variations in motilin sensitivity (or other ligands for receptors undergoing pseudonymization) on gross physiological functions? These are important questions for understanding animal variation.


Assuntos
Trato Gastrointestinal/fisiologia , Motilina/metabolismo , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeos/metabolismo , Animais , Variação Genética , Grelina/metabolismo , Cobaias , Humanos , Camundongos , Ratos , Receptores de Grelina/metabolismo , Roedores , Especificidade da Espécie
6.
Sci Rep ; 12(1): 1014, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046451

RESUMO

The objectives of this research were to study the changes of phenolic compounds in vegetable (yellow VS green) tablets with/without probiotics (Lacticaseibacillus rhamnosus LR5) supplementation by using high performance liquid chromatography and probiotic survivability through the simulated gastrointestinal tract. The green vegetable tablets with/without probiotics had a greater (p ≤ 0.05) phenolic content compared to the yellow ones. There were no significant differences of most phenolic compound contents between probiotic-supplemented vegetable tablets and non-probiotic supplemented ones (p > 0.05). The contents of ferulic acid, epicatechin, tannic acid and rutin for both vegetable tablets tended to decrease through passing the stomach (1 and 2 h) and small intestine (2 and 4 h), however, the content of catechin in the yellow vegetable tablets tended to increase. The results also showed that the survival of Lacticaseibacillus rhamnosus LR5 slightly decreased through the simulated gastrointestinal tract. The vibrations from FTIR appeared in the wave length of 4000-3100, 3000-2800 and 1652-1545 cm-1, which accounted for the change in the N-H bonds of the amine group, changes in the structure of fatty acids and the change of carbonyl groups, respectively. This work highlighted the opportunity of application of probiotics in food products; especially non-dairy foods for consumer with dairy allergy.


Assuntos
Lactobacillus rhamnosus/fisiologia , Fenóis/análise , Probióticos/análise , Trato Gastrointestinal/fisiologia , Comprimidos/análise , Verduras/química
7.
AAPS J ; 24(1): 21, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34988679

RESUMO

While the concept of 'Virtual Bioequivalence' (VBE) using a combination of modelling, in vitro tests and integration of pre-existing data on systems and drugs is growing from its infancy, building confidence on VBE outcomes requires demonstration of its ability not only in predicting formulation-dependent systemic exposure but also the expected degree of population variability. The concept of variation influencing the outcome of BE, despite being hidden with the cross-over nature of common BE studies, becomes evident when dealing with the acceptance criteria that consider the 90% confidence interval (CI) around the relative bioavailability. Hence, clinical studies comparing a reference product against itself may fail due to within-subject variations associated with the two occasions that the individual receives the same formulation. In this proof-of-concept study, we offer strategies to capture the most realistic predictions of CI around the pharmacokinetic parameters by propagating physiological variations through physiologically based pharmacokinetic modelling. The exercise indicates feasibility of the approach based on comparisons made between the simulated and observed WSV of pharmacokinetic parameters tested for a clinical bioequivalence case study. However, it also indicates that capturing WSV of a large array of physiological parameters using backward translation modelling from repeated BE studies of reference products would require a diverse set of drugs and formulations. The current case study of delayed-release formulation of posaconazole was able to declare certain combinations of WSV of physiological parameters as 'not plausible'. The eliminated sets of WSV values would be applicable to PBPK models of other drugs and formulations. Graphical Abstract.


Assuntos
Modelos Biológicos , Projetos de Pesquisa , Triazóis/administração & dosagem , Adolescente , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Preparações de Ação Retardada , Trato Gastrointestinal/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Equivalência Terapêutica , Triazóis/farmacocinética , Adulto Jovem
8.
J Exp Med ; 219(2)2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35024767

RESUMO

Gut innate lymphoid cells (ILCs) show remarkable phenotypic diversity, yet microenvironmental factors that drive this plasticity are incompletely understood. The balance between NKp46+, IL-22-producing, group 3 ILCs (ILC3s) and interferon (IFN)-γ-producing group 1 ILCs (ILC1s) contributes to gut homeostasis. The gut mucosa is characterized by physiological hypoxia, and adaptation to low oxygen is mediated by hypoxia-inducible transcription factors (HIFs). However, the impact of HIFs on ILC phenotype and gut homeostasis is not well understood. Mice lacking the HIF-1α isoform in NKp46+ ILCs show a decrease in IFN-γ-expressing, T-bet+, NKp46+ ILC1s and a concomitant increase in IL-22-expressing, RORγt+, NKp46+ ILC3s in the gut mucosa. Single-cell RNA sequencing revealed HIF-1α as a driver of ILC phenotypes, where HIF-1α promotes the ILC1 phenotype by direct up-regulation of T-bet. Loss of HIF-1α in NKp46+ cells prevents ILC3-to-ILC1 conversion, increases the expression of IL-22-inducible genes, and confers protection against intestinal damage. Taken together, our results suggest that HIF-1α shapes the ILC phenotype in the gut.


Assuntos
Antígenos Ly/metabolismo , Plasticidade Celular/imunologia , Trato Gastrointestinal/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imunidade Inata , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Animais , Biomarcadores , Suscetibilidade a Doenças , Expressão Gênica , Perfilação da Expressão Gênica , Homeostase , Imunidade nas Mucosas , Imunofenotipagem , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Subpopulações de Linfócitos , Camundongos , Camundongos Knockout , Microbiota , Análise de Célula Única
9.
Gut Microbes ; 14(1): 1997296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34978524

RESUMO

The human gastrointestinal tract is home to trillions of microbes. Gut microbial communities have a significant regulatory role in the intestinal physiology, such as gut motility. Microbial effect on gut motility is often evoked by bioactive molecules from various sources, including microbial break down of carbohydrates, fibers or proteins. In turn, gut motility regulates the colonization within the microbial ecosystem. However, the underlying mechanisms of such regulation remain obscure. Deciphering the inter-regulatory mechanisms of the microbiota and bowel function is crucial for the prevention and treatment of gut dysmotility, a comorbidity associated with many diseases. In this review, we present an overview of the current knowledge on the impact of gut microbiota and its products on bowel motility. We discuss the currently available techniques employed to assess the changes in the intestinal motility. Further, we highlight the open challenges, and incorporate biophysical elements of microbes-motility interplay, in an attempt to lay the foundation for describing long-term impacts of microbial metabolite-induced changes in gut motility.


Assuntos
Bactérias/metabolismo , Microbioma Gastrointestinal , Motilidade Gastrointestinal , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Animais , Bactérias/classificação , Bactérias/genética , Simulação por Computador , Humanos
10.
Artigo em Inglês | MEDLINE | ID: mdl-34737157

RESUMO

Prominent ontogenetic changes of the gastrointestinal tract (GIT) should occur in mammals whose neonatal diet of milk differs from that of adults, and especially in herbivores (as vegetation is particularly distinct from milk), and even more so in foregut fermenters, whose forestomach only becomes functionally relevant with vegetation intake. Due to the protracted lactation in marsupials, ontogenetic differences can be particularly well investigated in this group. Here, we report body mass (BM) scaling relationships of wet GIT content mass in 28 in-pouch young (50 g to 3 kg) and 15 adult (16-70 kg) western grey kangaroos Macropus fuliginosus melanops. Apart from the small intestinal contents, in-pouch young and adults did not differ in the scaling exponents ('slope' in log-log plots) but did differ in the scaling factor ('intercept'), with an implied substantial increase in wet GIT content mass during the out-of-pouch juvenile period. In contrast to forestomach contents, caecum contents were elevated in juveniles still in the pouch, suggestive of fermentative digestion of milk and intestinal secretion residues, particularly in the caecum. The substantial increase in GIT contents (from less than 1 to 10-20% of BM) was associated mainly with the increase in forestomach contents (from 25 to 80% of total GIT contents) and a concomitant decrease in small intestine contents (from 50 to 8%), emphasizing the shifting relevance of auto-enzymatic and allo-enzymatic (microbial) digestion. There was a concomitant increase in the contents-to-tissue ratio of the fermentation chambers (forestomach and caecum), but this ratio generally did not change for the small intestine. Our study not only documents significant ontogenetic changes in digestive morpho-physiology, but also exemplifies the usefulness of intraspecific allometric analyses for quantifying these changes.


Assuntos
Conteúdo Gastrointestinal/química , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/fisiologia , Macropodidae/crescimento & desenvolvimento , Macropodidae/fisiologia , Animais , Fenômenos Fisiológicos do Sistema Digestório , Feminino , Fermentação/fisiologia , Masculino , Modelos Biológicos
11.
Mucosal Immunol ; 15(1): 27-39, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471248

RESUMO

The enteric nervous system (ENS) of the gastrointestinal (GI) tract interacts with the local immune system bidirectionally. Recent publications have demonstrated that such interactions can maintain normal GI functions during homeostasis and contribute to pathological symptoms during infection and inflammation. Infection can also induce long-term changes of the ENS resulting in the development of post-infectious GI disturbances. In this review, we discuss how the ENS can regulate and be regulated by immune responses and how such interactions control whole tissue physiology. We also address the requirements for the proper regeneration of the ENS and restoration of GI function following the resolution of infection.


Assuntos
Sistema Nervoso Entérico/fisiologia , Trato Gastrointestinal/fisiologia , Infecções/imunologia , Inflamação/imunologia , Neuroimunomodulação/fisiologia , Animais , Homeostase , Humanos
12.
Biotechnol Adv ; 54: 107796, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34252564

RESUMO

The human digestion is a multi-step and multi-compartment process essential for human health, at the heart of many issues raised by academics, the medical world and industrials from the food, nutrition and pharma fields. In the first years of life, major dietary changes occur and are concomitant with an evolution of the whole child digestive tract anatomy and physiology, including colonization of gut microbiota. All these phenomena are influenced by child exposure to environmental compounds, such as drugs (especially antibiotics) and food pollutants, but also childhood infections. Due to obvious ethical, regulatory and technical limitations, in vivo approaches in animal and human are more and more restricted to favor complementary in vitro approaches. This review summarizes current knowledge on the evolution of child gut physiology from birth to 3 years old regarding physicochemical, mechanical and microbial parameters. Then, all the available in vitro models of the child digestive tract are described, ranging from the simplest static mono-compartmental systems to the most sophisticated dynamic and multi-compartmental models, and mimicking from the oral phase to the colon compartment. Lastly, we detail the main applications of child gut models in nutritional, pharmaceutical and microbiological studies and discuss the limitations and challenges facing this field of research.


Assuntos
Poluentes Ambientais , Microbioma Gastrointestinal , Animais , Criança , Digestão , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Humanos
13.
J Physiol ; 600(5): 1053-1078, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34152020

RESUMO

The number of people living with obesity has tripled worldwide since 1975 with serious implications for public health, as obesity is linked to a significantly higher chance of early death from associated comorbidities (metabolic syndrome, type 2 diabetes, cardiovascular disease and cancer). As obesity is a consequence of food intake exceeding the demands of energy expenditure, efforts are being made to better understand the homeostatic and hedonic mechanisms governing food intake. Gastrointestinal peptides are secreted from enteroendocrine cells in response to nutrient and energy intake, and modulate food intake either via afferent nerves, including the vagus nerve, or directly within the central nervous system, predominantly gaining access at circumventricular organs. Enteroendocrine hormones modulate homeostatic control centres at hypothalamic nuclei and the dorso-vagal complex. Additional roles of these peptides in modulating hedonic food intake and/or preference via the neural systems of reward are starting to be elucidated, with both peripheral and central peptide sources potentially contributing to central receptor activation. Pharmacological interventions and gastric bypass surgery for the treatment of type 2 diabetes and obesity elevate enteroendocrine hormone levels and also alter food preference. Hence, understanding of the hedonic mechanisms mediated by gut peptide action could advance development of potential therapeutic strategies for the treatment of obesity and its comorbidities.


Assuntos
Diabetes Mellitus Tipo 2 , Regulação do Apetite/fisiologia , Ingestão de Alimentos , Trato Gastrointestinal/fisiologia , Humanos , Obesidade , Peptídeos
14.
Mol Pharm ; 19(1): 213-226, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34914382

RESUMO

Oral drug absorption modeling has developed at a rapid pace in the 40 years or so since the first ideas for mathematical approaches to oral absorption were introduced. The success of compartmental approaches accelerated the uptake of absorption modeling, and over the last 20 years, work on absorption modeling has shifted almost exclusively to the compartmental framework. This report describes a new noncompartmental absorption modeling framework, the Lilly Absorption Modeling Platform (LAMP). LAMP connects a well-mixed stomach to a continuous tube model of the small intestine with plug flow. Within the continuous tube framework, the model includes intestinal mixing and a novel highly tunable precipitation model that can describe a combination of rapid nucleation and slow growth. The framework is designed to balance speed, consistency, and ease of use with a minimum of model complexity to capture the essential features of gastrointestinal (GI) physiology and critical elements of the oral absorption process. The model was validated based on predictions of the fraction absorbed and the maximum absorbable dose for a set of Eli Lilly and Company clinical compounds.


Assuntos
Absorção Gastrointestinal , Administração Oral , Indústria Farmacêutica , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/fisiologia , Humanos , Modelos Biológicos
16.
PLoS Comput Biol ; 17(12): e1009644, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34871315

RESUMO

Peristalsis, the coordinated contraction-relaxation of the muscles of the stomach is important for normal gastric motility and is impaired in motility disorders. Coordinated electrical depolarizations that originate and propagate within a network of interconnected layers of interstitial cells of Cajal (ICC) and smooth muscle (SM) cells of the stomach wall as a slow-wave, underly peristalsis. Normally, the gastric slow-wave oscillates with a single period and uniform rostrocaudal lag, exhibiting network entrainment. Understanding of the integrative role of neurotransmission and intercellular coupling in the propagation of an entrained gastric slow-wave, important for understanding motility disorders, however, remains incomplete. Using a computational framework constituted of a novel gastric motility network (GMN) model we address the hypothesis that engaging biological oscillators (i.e., ICCs) by constitutive gap junction coupling mechanisms and enteric neural innervation activated signals can confer a robust entrained gastric slow-wave. We demonstrate that while a decreasing enteric neural innervation gradient that modulates the intracellular IP3 concentration in the ICCs can guide the aboral slow-wave propagation essential for peristalsis, engaging ICCs by recruiting the exchange of second messengers (inositol trisphosphate (IP3) and Ca2+) ensures a robust entrained longitudinal slow-wave, even in the presence of biological variability in electrical coupling strengths. Our GMN with the distinct intercellular coupling in conjunction with the intracellular feedback pathways and a rostrocaudal enteric neural innervation gradient allows gastric slow waves to oscillate with a moderate range of frequencies and to propagate with a broad range of velocities, thus preventing decoupling observed in motility disorders. Overall, the findings provide a mechanistic explanation for the emergence of decoupled slow waves associated with motility impairments of the stomach, offer directions for future experiments and theoretical work, and can potentially aid in the design of new interventional pharmacological and neuromodulation device treatments for addressing gastric motility disorders.


Assuntos
Relógios Biológicos/fisiologia , Trato Gastrointestinal , Músculo Liso , Peristaltismo/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , Animais , Cálcio/metabolismo , Biologia Computacional , Sinapses Elétricas/fisiologia , Trato Gastrointestinal/inervação , Trato Gastrointestinal/fisiologia , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Células Intersticiais de Cajal/fisiologia , Potenciais da Membrana/fisiologia , Modelos Biológicos , Contração Muscular/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia
17.
Sci Rep ; 11(1): 23117, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848778

RESUMO

All animals carry specialized microbiomes, and their gut microbiota are continuously released into the environment through excretion of waste. Here we propose the meta-gut as a novel conceptual framework that addresses the ability of the gut microbiome released from an animal to function outside the host and alter biogeochemical processes mediated by microbes. We demonstrate this dynamic in the hippopotamus (hippo) and the pools they inhabit. We used natural field gradients and experimental approaches to examine fecal and pool water microbial communities and aquatic biogeochemistry across a range of hippo inputs. Sequencing using 16S RNA methods revealed community coalescence between hippo gut microbiomes and the active microbial communities in hippo pools that received high inputs of hippo feces. The shared microbiome between the hippo gut and the waters into which they excrete constitutes a meta-gut system that could influence the biogeochemistry of recipient ecosystems and provide a reservoir of gut microbiomes that could influence other hosts. We propose that meta-gut dynamics may also occur where other animal species congregate in high densities, particularly in aquatic environments.


Assuntos
Artiodáctilos/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Trato Gastrointestinal/fisiologia , RNA Ribossômico 16S/genética , Animais , Bactérias/genética , Ecossistema , Água Doce/microbiologia , Funções Verossimilhança , Modelos Lineares , Filogenia , RNA Ribossômico 16S/metabolismo , Rios , Microbiologia da Água
18.
Int J Mol Sci ; 22(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34948310

RESUMO

Extracellular vesicles (EVs) are a group of membrane vesicles that play important roles in cell-to-cell and interspecies/interkingdom communications by modulating the pathophysiological conditions of recipient cells. Recent evidence has implied their potential roles in the gut-brain axis (GBA), which is a complex bidirectional communication system between the gut environment and brain pathophysiology. Despite the evidence, the roles of EVs in the gut microenvironment in the GBA are less highlighted. Moreover, there are critical challenges in the current GBA models and analyzing techniques for EVs, which may hinder the research. Currently, advances in organ-on-a-chip (OOC) technologies have provided a promising solution. Here, we review the potential effects of EVs occurring in the gut environment on brain physiology and behavior and discuss how to apply OOCs to research the GBA mediated by EVs in the gut microenvironment.


Assuntos
/fisiologia , Encéfalo/fisiologia , Microambiente Celular/fisiologia , Vesículas Extracelulares/fisiologia , Trato Gastrointestinal/fisiologia , Animais , Sistema Digestório , Humanos , Dispositivos Lab-On-A-Chip
19.
Front Immunol ; 12: 775526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956204

RESUMO

Diverse liver diseases undergo a similar pathophysiological process in which liver regeneration follows a liver injury. Given the important role of the gut-liver axis in health and diseases, the role of gut microbiota-derived signals in liver injury and regeneration has attracted much attention. It has been observed that the composition of gut microbiota dynamically changes in the process of liver regeneration after partial hepatectomy, and gut microbiota modulation by antibiotics or probiotics affects both liver injury and regeneration. Mechanically, through the portal vein, the liver is constantly exposed to gut microbial components and metabolites, which have immense effects on the immunity and metabolism of the host. Emerging data demonstrate that gut-derived lipopolysaccharide, gut microbiota-associated bile acids, and other bacterial metabolites, such as short-chain fatty acids and tryptophan metabolites, may play multifaceted roles in liver injury and regeneration. In this perspective, we provide an overview of the possible molecular mechanisms by which gut microbiota-derived signals modulate liver injury and regeneration, highlighting the potential roles of gut microbiota in the development of gut microbiota-based therapies to alleviate liver injury and promote liver regeneration.


Assuntos
Suscetibilidade a Doenças , Retroalimentação Fisiológica , Trato Gastrointestinal/fisiologia , Homeostase , Fígado/fisiologia , Animais , Ácidos e Sais Biliares/metabolismo , Biomarcadores , Disbiose , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/imunologia , Humanos , Lipopolissacarídeos/imunologia , Regeneração Hepática , Regeneração , Transdução de Sinais
20.
Microbiologyopen ; 10(6): e1250, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34964292

RESUMO

Apostichopus japonicus is a useful model for studying organ regeneration, and the gut microbiota is important for host organ regeneration. However, the reconstruction process and the mechanisms of gut microbiota assembly during gut regeneration in sea cucumbers have not been well studied. In the present study, gut regeneration was induced (via evisceration) in A. japonicus, and gut immune responses and bacterial diversity were investigated to reveal gut microbiota assembly and its possible mechanisms during gut regeneration. The results revealed that bacterial community reconstruction involved two stages with distinct assembly mechanisms, where the reconstructed community was initiated from the bacterial consortium in the residual digestive tract and tended to form a novel microbiota in the later stage of reconstruction. Together, the results of immunoenzyme assays, community phylogenetic analysis, and source tracking suggested that the host deterministic process was stronger in the initial stage than in the later stage. The bacterial interactions that occurred were significantly different between the two stages. Positive interactions dominated in the initial stage, while more complex and competitive interactions developed in the later stage. Such a dynamic bacterial community could provide the host with energetic and immune benefits that promote gut regeneration and functional recovery. The results of the present study provide insights into the processes and mechanisms of gut microbiota assembly during intestinal regeneration that are valuable for understanding gut regeneration mechanisms mediated by the microbiota.


Assuntos
Microbioma Gastrointestinal , Regeneração , Stichopus/microbiologia , Stichopus/fisiologia , Animais , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Imunidade , Interações Microbianas , Stichopus/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...