Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.462
Filtrar
1.
Int J Mol Sci ; 22(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34639103

RESUMO

Various pathogens, such as Ebola virus, Marburg virus, Nipah virus, Hendra virus, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV), Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and SARS-CoV-2, are threatening human health worldwide. The natural hosts of these pathogens are thought to be bats. The rousette bat, a megabat, is thought to be a natural reservoir of filoviruses, including Ebola and Marburg viruses. Additionally, the rousette bat showed a transient infection in the experimental inoculation of SARS-CoV-2. In the current study, we established and characterized intestinal organoids from Leschenault's rousette, Rousettus leschenaultii. The established organoids successfully recapitulated the characteristics of intestinal epithelial structure and morphology, and the appropriate supplements necessary for long-term stable culture were identified. The organoid showed susceptibility to Pteropine orthoreovirus (PRV) but not to SARS-CoV-2 in experimental inoculation. This is the first report of the establishment of an expandable organoid culture system of the rousette bat intestinal organoid and its sensitivity to bat-associated viruses, PRV and SARS-CoV-2. This organoid is a useful tool for the elucidation of tolerance mechanisms of the emerging rousette bat-associated viruses such as Ebola and Marburg virus.


Assuntos
COVID-19/virologia , Quirópteros/virologia , Organoides/virologia , Orthoreovirus/fisiologia , Infecções por Reoviridae/virologia , SARS-CoV-2/fisiologia , Animais , COVID-19/veterinária , Técnicas de Cultura de Células , Células Cultivadas , Quirópteros/fisiologia , Humanos , Intestinos/citologia , Intestinos/virologia , Organoides/citologia , Infecções por Reoviridae/veterinária
2.
Arch Biochem Biophys ; 712: 109044, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34597656

RESUMO

The pathogenesis of chronic kidney disease (CKD) is closely related to the changes in the intestinal microbiota and integrity. Our previous studies have shown the accumulation of hydrogen sulfide (H2S)-producing bacterial family, Desulfovibrionacea, in the colon of a murine model of CKD, suggesting that the increased H2S contributes to the impaired intestinal integrity in CKD. Here, we investigated the anti-proliferative effect of H2S in the intestinal epithelial cells. A slow- H2S releasing molecule GYY4137 ((p-methoxyphenyl)morpholino-phosphinodithioic acid) reduced the proliferation of Caco-2 and IEC-6 cells. Flow cytometric analysis demonstrated that GYY4137 accumulated Caco-2 cells in the S phase fraction, suggesting that H2S arrested the cell cycle at G2 and/or M phases. The RNA sequencing analysis demonstrated that GYY4137 modulated the mRNA expression of the genes involved in the G2/M and the spindle assembly checkpoints; increased mRNA levels of Cdkn1a, Gadd45a, and Sfn and decreased mRNA levels of Cdc20, Pttg1, and Ccnb1 were observed. These alterations were confirmed by quantitative reverse transcription-polymerase chain reaction and Western blot analyses. Besides, studies exploring the MEK inhibitor indicated that MEK activation is involved in the GYY4137-mediated increase in the Sfn expression. Altogether, our data showed that H2S reduced the proliferation of intestinal epithelial cells through transcriptional regulation in G2/M and the spindle assembly checkpoints. This may be one of the underlying mechanisms for the observed impaired intestinal integrity in CKD.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Animais , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Intestinos/citologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Compostos Organotiofosforados/farmacologia , Ratos
3.
Chem Biol Interact ; 348: 109640, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34506767

RESUMO

Intestinal stem cell (ISC)-driven intestinal homeostasis is subjected to dual regulation by dietary nutrients and toxins. Our study investigated the use of lauric acid (LA) to alleviate deoxynivalenol (DON)-induced intestinal epithelial damage. C57BL/6 mice in the control, LA, DON, and LA + DON groups were orally administered PBS, 10 mg/kg BW LA, 2 mg/kg BW DON, and 10 mg/kg BW LA + 2 mg/kg BW DON for 10 days. The results showed that LA increased the average daily gain and average daily feed intake of the mice exposed to DON. Moreover, the DON-triggered impairment of jejunal morphology and barrier function was significantly improved after LA supplementation. Moreover, LA rescued ISC proliferation, inhibited intestinal cell apoptosis, and promoted ISC differentiation into absorptive cells, goblet cells, and Paneth cells. The jejunum crypt cells from the mice in the LA group expanded into enteroids, resulting in a significantly greater enteroid area than that in the DON group. Furthermore, LA reversed the DON-mediated inhibition of the Akt/mTORC1/S6K1 signaling axis in the jejunum. Our results indicated that LA accelerates ISC regeneration to repair intestinal epithelial damage after DON insult by reactivating the Akt/mTORC1/S6K1 signaling pathway, which provides new implications for the function of LA in ISCs.


Assuntos
Intestinos/citologia , Ácidos Láuricos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/citologia , Tricotecenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
4.
Life Sci ; 284: 119920, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478760

RESUMO

AIMS: The sustained activation of intestinal mechanistic target of rapamycin complex 1 (mTORC1) brought about by repeated mucosal insult or injury has been linked to escalation of gut inflammatory response, which may progress to damage the epithelium if not controlled. This study investigated the role of mTORC1 in the response of macrophage and enterocyte to inflammatory stimuli. MATERIALS AND METHODS: We genetically manipulated human THP-1 monocytes and epithelial intestinal Caco-2 cells to generate stable cell lines with baseline, low or high mTORC1 kinase activity. The effects of THP-1 macrophage secretions onto Caco-2 cells were investigated by means of conditioned media transfer experiments. KEY FINDINGS: The priming of mTORC1 for activation promoted lipopolysaccharide (LPS)-mediated THP-1 macrophage immune response as evidenced by the stimulation of inflammatory mediators (TNFα, IL-6, IL-8, IL-1ß and IL-10). The treatment of THP-1 macrophages with LPS more than the manipulated level of mTORC1 activity of macrophages determined whether cytokine gene expression was induced in Caco-2 cells. LPS carry over was not responsible for the stimulation of Caco-2 cells' cytokine response. Knocking down Raptor in Caco-2 cells or treating Caco-2 cells with rapamycin enhanced Caco-2 TNFα gene expression revealing the anti-inflammatory role of a functional mTORC1 in intestinal epithelial cells exposed to macrophage-derived pro-inflammatory stimuli. SIGNIFICANCE: Taken together, mTORC1 differentially impacts the immune responses of THP-1-derived macrophages and Caco-2 epithelial cells when placed in a pro-inflammatory microenvironment.


Assuntos
Citocinas/metabolismo , Células Epiteliais/metabolismo , Mediadores da Inflamação/metabolismo , Intestinos/citologia , Macrófagos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Células CACO-2 , Meios de Cultivo Condicionados/farmacologia , Citocinas/genética , Citoproteção/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Modelos Biológicos , Transdução de Sinais/efeitos dos fármacos , Células THP-1 , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
5.
Nutrients ; 13(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34579065

RESUMO

Dietary fibers have well-known beneficial effects on human health, but their anti-infectious properties against human enteric pathogens have been poorly investigated. Enterotoxigenic Escherichia coli (ETEC) is the main agent of travelers' diarrhea, against which targeted preventive strategies are currently lacking. ETEC pathogenesis relies on multiple virulence factors allowing interactions with the intestinal mucosal layer and toxins triggering the onset of diarrheal symptoms. Here, we used complementary in vitro assays to study the antagonistic properties of eight fiber-containing products from cereals, legumes or microbes against the prototypical human ETEC strain H10407. Inhibitory effects of these products on the pathogen were tested through growth, toxin production and mucus/cell adhesion inhibition assays. None of the tested compounds inhibited ETEC strain H10407 growth, while lentil extract was able to decrease heat labile toxin (LT) concentration in culture media. Lentil extract and specific yeast cell walls also interfered with ETEC strain H10407 adhesion to mucin beads and human intestinal cells. These results constitute a first step in the use of dietary fibers as a nutritional strategy to prevent ETEC infection. Further work will be dedicated to the study of fiber/ETEC interactions within a complex gut microbial background.


Assuntos
Diarreia/microbiologia , Fibras na Dieta/farmacologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Doenças Transmitidas por Alimentos/microbiologia , Fatores de Virulência , Adesão Celular , Diarreia/prevenção & controle , Fibras na Dieta/uso terapêutico , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/metabolismo , Escherichia coli Enterotoxigênica/patogenicidade , Enterotoxinas/metabolismo , Infecções por Escherichia coli/prevenção & controle , Proteínas de Escherichia coli/metabolismo , Doenças Transmitidas por Alimentos/prevenção & controle , Humanos , Intestinos/citologia , Intestinos/microbiologia , Lens (Planta)/química , Testes de Sensibilidade Microbiana , Mucinas , Muco , Sementes/química , Viagem , Leveduras/química
6.
Nature ; 597(7875): 250-255, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34497389

RESUMO

The cellular landscape of the human intestinal tract is dynamic throughout life, developing in utero and changing in response to functional requirements and environmental exposures. Here, to comprehensively map cell lineages, we use single-cell RNA sequencing and antigen receptor analysis of almost half a million cells from up to 5 anatomical regions in the developing and up to 11 distinct anatomical regions in the healthy paediatric and adult human gut. This reveals the existence of transcriptionally distinct BEST4 epithelial cells throughout the human intestinal tract. Furthermore, we implicate IgG sensing as a function of intestinal tuft cells. We describe neural cell populations in the developing enteric nervous system, and predict cell-type-specific expression of genes associated with Hirschsprung's disease. Finally, using a systems approach, we identify key cell players that drive the formation of secondary lymphoid tissue in early human development. We show that these programs are adopted in inflammatory bowel disease to recruit and retain immune cells at the site of inflammation. This catalogue of intestinal cells will provide new insights into cellular programs in development, homeostasis and disease.


Assuntos
Envelhecimento , Sistema Nervoso Entérico/citologia , Feto/citologia , Saúde , Intestinos/citologia , Intestinos/crescimento & desenvolvimento , Linfonodos/citologia , Linfonodos/crescimento & desenvolvimento , Adulto , Animais , Criança , Doença de Crohn/patologia , Conjuntos de Dados como Assunto , Sistema Nervoso Entérico/anatomia & histologia , Sistema Nervoso Entérico/embriologia , Sistema Nervoso Entérico/crescimento & desenvolvimento , Células Epiteliais/citologia , Feminino , Feto/anatomia & histologia , Feto/embriologia , Humanos , Intestinos/embriologia , Intestinos/inervação , Linfonodos/embriologia , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Organogênese , Receptores de IgG/metabolismo , Transdução de Sinais , Análise Espaço-Temporal , Fatores de Tempo
7.
Exp Cell Res ; 408(1): 112838, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560103

RESUMO

CTP synthase (CTPS) senses all four nucleotides and forms filamentous structures termed cytoophidia in all three domains of life. How CTPS and cytoophidia function in a developmental context, however, remains underexplored. We report that CTPS forms cytoophidia in a subset of cells in the Drosophila midgut. We found that cytoophidia exist in intestinal stem cells (ISC) and enteroblasts in similar proportions. Both refeeding after starvation and feeding with dextran sulfate sodium (DSS) induce ISC proliferation and elongate cytoophidia. Knockdown of CTPS inhibits ISC proliferation. Remarkably, disruption of CTPS cytoophidia inhibits DSS-induced ISC proliferation. Taken together, these data suggest that both the expression level and the filament-form property of CTPS are crucial for intestinal homeostasis in Drosophila.


Assuntos
Carbono-Nitrogênio Ligases/metabolismo , Sulfato de Dextrana/farmacologia , Homeostase/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Animais , Carbono-Nitrogênio Ligases/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Drosophila , Homeostase/fisiologia , Intestinos/citologia , Intestinos/efeitos dos fármacos , Células-Tronco/citologia
8.
Nat Commun ; 12(1): 5674, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584098

RESUMO

Emerging evidence is revealing that alterations in gut microbiota are associated with colorectal cancer (CRC). However, very little is currently known about whether and how gut microbiota alterations are causally associated with CRC development. Here we show that 12 faecal bacterial taxa are enriched in CRC patients in two independent cohort studies. Among them, 2 Porphyromonas species are capable of inducing cellular senescence, an oncogenic stress response, through the secretion of the bacterial metabolite, butyrate. Notably, the invasion of these bacteria is observed in the CRC tissues, coinciding with the elevation of butyrate levels and signs of senescence-associated inflammatory phenotypes. Moreover, although the administration of these bacteria into ApcΔ14/+ mice accelerate the onset of colorectal tumours, this is not the case when bacterial butyrate-synthesis genes are disrupted. These results suggest a causal relationship between Porphyromonas species overgrowth and colorectal tumourigenesis which may be due to butyrate-induced senescence.


Assuntos
Bactérias/metabolismo , Butiratos/metabolismo , Carcinogênese/patologia , Neoplasias Colorretais/patologia , Microbioma Gastrointestinal , Bactérias/classificação , Bactérias/genética , Senescência Celular/fisiologia , Neoplasias Colorretais/microbiologia , Células Epiteliais/microbiologia , Células Epiteliais/fisiologia , Fezes/microbiologia , Humanos , Intestinos/citologia , Intestinos/microbiologia , Intestinos/fisiologia , Porphyromonas/genética , Porphyromonas/metabolismo , RNA Ribossômico 16S/genética
9.
Nature ; 596(7871): 262-267, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349263

RESUMO

Regulated cell death is an integral part of life, and has broad effects on organism development and homeostasis1. Malfunctions within the regulated cell death process, including the clearance of dying cells, can manifest in diverse pathologies throughout various tissues including the gastrointestinal tract2. A long appreciated, yet elusively defined relationship exists between cell death and gastrointestinal pathologies with an underlying microbial component3-6, but the direct effect of dying mammalian cells on bacterial growth is unclear. Here we advance a concept that several Enterobacteriaceae, including patient-derived clinical isolates, have an efficient growth strategy to exploit soluble factors that are released from dying gut epithelial cells. Mammalian nutrients released after caspase-3/7-dependent apoptosis boosts the growth of multiple Enterobacteriaceae and is observed using primary mouse colonic tissue, mouse and human cell lines, several apoptotic triggers, and in conventional as well as germ-free mice in vivo. The mammalian cell death nutrients induce a core transcriptional response in pathogenic Salmonella, and we identify the pyruvate formate-lyase-encoding pflB gene as a key driver of bacterial colonization in three contexts: a foodborne infection model, a TNF- and A20-dependent cell death model, and a chemotherapy-induced mucositis model. These findings introduce a new layer to the complex host-pathogen interaction, in which death-induced nutrient release acts as a source of fuel for intestinal bacteria, with implications for gut inflammation and cytotoxic chemotherapy treatment.


Assuntos
Apoptose , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Intestinos/citologia , Intestinos/microbiologia , Acetiltransferases/genética , Acetiltransferases/metabolismo , Animais , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Células Epiteliais/patologia , Feminino , Doenças Transmitidas por Alimentos/microbiologia , Vida Livre de Germes , Interações Hospedeiro-Patógeno , Inflamação/metabolismo , Inflamação/microbiologia , Inflamação/patologia , Masculino , Camundongos , Mucosite/induzido quimicamente , Salmonella/enzimologia , Salmonella/genética , Salmonella/crescimento & desenvolvimento , Salmonella/metabolismo , Transcriptoma , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Toxicol Lett ; 351: 89-98, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34461197

RESUMO

Lipophilic phycotoxins are secondary metabolites produced by phytoplankton. They can accumulate in edible filtering-shellfish and cause human intoxications, particularly gastrointestinal symptoms. Up to now, the in vitro intestinal effects of these toxins have been mainly investigated on simple monolayers of intestinal cells such as the enterocyte-like Caco-2 cell line. Recently, the combination of Caco-2 cells with mucus secreting HT29-MTX cell line has been also used to mimic the complexity of the human intestinal epithelium. Besides, enteric glial cells (EGC) from the enteric nervous system identified in the gut mucosa have been largely shown to be involved in gut functions. Therefore, using a novel model integrating Caco-2 and HT29-MTX cells co-cultured on inserts with EGC seeded in the basolateral compartment, we examined the toxicological effects of two phycotoxins, pectenotoxin-2 (PTX2) and okadaic acid (OA). Cell viability, morphology, barrier integrity, inflammation, barrier crossing, and the response of some specific glial markers were evaluated using a broad set of methodologies. The toxicity of PTX2 was depicted by a slight decrease of viability and integrity as well as a slight increase of inflammation of the Caco-2/HT29-MTX co-cultures. PTX2 induced some modifications of EGC morphology. OA induced IL-8 release and decreased viability and integrity of Caco-2/HT29-MTX cell monolayers. EGC viability was slightly affected by OA. The presence of EGC reinforced barrier integrity and reduced the inflammatory response of the epithelial barrier following OA exposure. The release of GDNF and BDNF gliomediators by EGC could be implicated in the protection observed.


Assuntos
Técnicas de Cocultura/métodos , Furanos/toxicidade , Intestinos/citologia , Macrolídeos/toxicidade , Neuroglia/efeitos dos fármacos , Ácido Okadáico/toxicidade , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Células HT29 , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Neuroglia/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo
11.
Sci Rep ; 11(1): 15940, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354169

RESUMO

Previously, genetic lineage tracing based on the mesothelial marker Wt1, appeared to show that peritoneal mesothelial cells have a range of differentiative capacities and are the direct progenitors of vascular smooth muscle in the intestine. However, it was not clear whether this was a temporally limited process or continued throughout postnatal life. Here, using a conditional Wt1-based genetic lineage tracing approach, we demonstrate that the postnatal and adult peritoneum covering intestine, mesentery and body wall only maintained itself and failed to contribute to other visceral tissues. Pulse-chase experiments of up to 6 months revealed that Wt1-expressing cells remained confined to the peritoneum and failed to differentiate into cellular components of blood vessels or other tissues underlying the peritoneum. Our data confirmed that the Wt1-lineage system also labelled submesothelial cells. Ablation of Wt1 in adult mice did not result in changes to the intestinal wall architecture. In the heart, we observed that Wt1-expressing cells maintained the epicardium and contributed to coronary vessels in newborn and adult mice. Our results demonstrate that Wt1-expressing cells in the peritoneum have limited differentiation capacities, and that contribution of Wt1-expressing cells to cardiac vasculature is based on organ-specific mechanisms.


Assuntos
Diferenciação Celular/genética , Proteínas WT1/genética , Animais , Linhagem da Célula/genética , Vasos Coronários/citologia , Células Epiteliais/citologia , Epitélio , Feminino , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento/genética , Intestinos/citologia , Masculino , Camundongos , Músculo Liso Vascular/citologia , Pericárdio/citologia , Peritônio , Transcriptoma/genética , Proteínas WT1/metabolismo
12.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210022

RESUMO

Food additive amorphous silicon dioxide (SiO2) particles are manufactured by two different methods-precipitated and fumed procedures-which can induce different physicochemical properties and biological fates. In this study, precipitated and fumed SiO2 particles were characterized in terms of constituent particle size, hydrodynamic diameter, zeta potential, surface area, and solubility. Their fates in intestinal cells, intestinal barriers, and tissues after oral administration in rats were determined by optimizing Triton X-114-based cloud point extraction (CPE). The results demonstrate that the constituent particle sizes of precipitated and fumed SiO2 particles were similar, but their aggregate states differed from biofluid types, which also affect dissolution properties. Significantly higher cellular uptake, intestinal transport amount, and tissue accumulation of precipitated SiO2 than of fumed SiO2 was found. The intracellular fates of both types of particles in intestinal cells were primarily particle forms, but slowly decomposed into ions during intestinal transport and after distribution in the liver, and completely dissolved in the bloodstream and kidneys. These findings will provide crucial information for understanding and predicting the potential toxicity of food additive SiO2 after oral intake.


Assuntos
Intestinos/química , Dióxido de Silício/administração & dosagem , Dióxido de Silício/síntese química , Administração Oral , Animais , Análise Química do Sangue , Células CACO-2 , Linhagem Celular Tumoral , Precipitação Química , Feminino , Humanos , Intestinos/citologia , Rim/química , Fígado/química , Nanopartículas , Octoxinol/química , Tamanho da Partícula , Ratos , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Solubilidade
13.
Arch Insect Biochem Physiol ; 108(1): e21832, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34250644

RESUMO

Autophagy is a critical mechanism for the self-renewal, proliferation, and differentiation of stem cells. Bombyx mori midgut has stem cells that play a role in the regeneration of the larval epithelium in larval stages and the formation of the pupal midgut epithelium during larval-pupal metamorphosis. In this study, the role of the autophagy mechanism in midgut stem cells during the formation of the pupal midgut was investigated. For this purpose, two different doses of autophagy inhibitor chloroquine were administered to B. mori larvae on days 7 and 8 of the fifth larval stage. Morphological changes during the formation process of the pupal epithelium, expression levels of autophagy-related genes Atg8 and Atg12 in stem cells, and the amounts of lysosomal enzyme acid phosphatase were determined after the application. The obtained findings were evaluated in comparison with the control groups. Abnormalities in the formation of the pupal midgut after inhibition of autophagy showed the significance of the autophagy mechanism during this period.


Assuntos
Autofagia , Bombyx , Intestinos , Metamorfose Biológica/fisiologia , Células-Tronco , Fosfatase Ácida/efeitos dos fármacos , Fosfatase Ácida/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Bombyx/citologia , Bombyx/metabolismo , Bombyx/fisiologia , Cloroquina/farmacologia , Intestinos/citologia , Intestinos/efeitos dos fármacos , Larva/citologia , Larva/metabolismo , Pupa/citologia , Pupa/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
14.
Am J Physiol Gastrointest Liver Physiol ; 321(3): G270-G279, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34288725

RESUMO

The use of human tissue stem cell-derived organoids has advanced our knowledge of human physiological and pathophysiological processes that are unable to be studied using other model systems. Increased understanding of human epithelial tissues including intestine, stomach, liver, pancreas, lung, and brain have been achieved using organoids. However, it is not yet clear whether these cultures recapitulate in vivo organ-to-organ signaling or communication. In this work, we demonstrate that mature stem cell-derived intestinal and liver organoid cultures each express functional molecules that modulate bile acid uptake and recycling. These organoid cultures can be physically coupled in a Transwell system and display increased secretion of fibroblast growth factor 19 (FGF19) (intestine) and downregulation of P450 enzyme cholesterol 7 α-hydroxylase (CYP7A) (liver) in response to apical exposure of the intestine to bile acids. This work establishes that organoid cultures can be used to study and therapeutically modulate interorgan interactions and advance the development of personalized approaches to medical care.NEW & NOTEWORTHY Interorgan signaling is a critical feature of human biology and physiology, yet has remained difficult to study due to the lack of in vitro models. Here, we demonstrate that physical coupling of ex vivo human intestine and liver epithelial organoid cultures recapitulates in vivo interorgan bile acid signaling. These results suggest that coupling of multiple organoid systems provides new models to investigate interorgan communication and advances our knowledge of human physiological and pathophysiological processes.


Assuntos
Diferenciação Celular/fisiologia , Intestinos/citologia , Organoides/citologia , Células-Tronco/citologia , Células Cultivadas , Circulação Êntero-Hepática/fisiologia , Humanos , Fígado/metabolismo , Estômago/citologia
15.
PLoS Genet ; 17(7): e1009649, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34228720

RESUMO

The differentiation efficiency of adult stem cells undergoes a significant decline in aged animals, which is closely related to the decline in organ function and age-associated diseases. However, the underlying mechanisms that ultimately lead to this observed decline of the differentiation efficiency of stem cells remain largely unclear. This study investigated Drosophila midguts and identified an obvious upregulation of caudal (cad), which encodes a homeobox transcription factor. This factor is traditionally known as a central regulator of embryonic anterior-posterior body axis patterning. This study reports that depletion of cad in intestinal stem/progenitor cells promotes quiescent intestinal stem cells (ISCs) to become activate and produce enterocytes in the midgut under normal gut homeostasis conditions. However, overexpression of cad results in the failure of ISC differentiation and intestinal epithelial regeneration after injury. Moreover, this study suggests that cad prevents intestinal stem/progenitor cell differentiation by modulating the Janus kinase/signal transducers and activators of the transcription pathway and Sox21a-GATAe signaling cascade. Importantly, the reduction of cad expression in intestinal stem/progenitor cells restrained age-associated gut hyperplasia in Drosophila. This study identified a function of the homeobox gene cad in the modulation of adult stem cell differentiation and suggested a potential gene target for the treatment of age-related diseases induced by age-related stem cell dysfunction.


Assuntos
Células-Tronco Adultas/metabolismo , Diferenciação Celular/genética , Proteínas de Drosophila/metabolismo , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Células-Tronco Adultas/fisiologia , Fatores Etários , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Genes Homeobox/genética , Proteínas de Homeodomínio/genética , Mucosa Intestinal/metabolismo , Intestinos/citologia , Janus Quinases/genética , Transdução de Sinais/genética , Fatores de Transcrição/genética
16.
Nutrients ; 13(6)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204790

RESUMO

The beneficial effects of human milk suppressing the development of intestinal pathologies such as necrotizing enterocolitis in preterm infants are widely known. Human milk (HM) is rich in a multitude of bioactive factors that play major roles in promoting postnatal maturation, differentiation, and the development of the microbiome. Previous studies showed that HM is rich in hyaluronan (HA) especially in colostrum and early milk. This study aims to determine the role of HA 35 KDa, a HM HA mimic, on intestinal proliferation, differentiation, and the development of the intestinal microbiome. We show that oral HA 35 KDa supplementation for 7 days in mouse pups leads to increased villus length and crypt depth, and increased goblet and Paneth cells, compared to controls. We also show that HA 35 KDa leads to an increased predominance of Clostridiales Ruminococcaceae, Lactobacillales Lactobacillaceae, and Clostridiales Lachnospiraceae. In seeking the mechanisms involved in the changes, bulk RNA seq was performed on samples from the terminal ileum and identified upregulation in several genes essential for cellular growth, proliferation, and survival. Taken together, this study shows that HA 35 KDa supplemented to mouse pups promotes intestinal epithelial cell proliferation, as well as the development of Paneth cells and goblet cell subsets. HA 35 KDa also impacted the intestinal microbiota; the implications of these responses need to be determined.


Assuntos
Suplementos Nutricionais , Microbioma Gastrointestinal/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Intestino Delgado/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Caliciformes/citologia , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/citologia , Intestinos/citologia , Intestinos/crescimento & desenvolvimento , Camundongos , Celulas de Paneth/citologia
17.
Elife ; 102021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196272

RESUMO

Enterovirus D68 (EV-D68) has been implicated in outbreaks of severe respiratory illness and is associated with acute flaccid myelitis (AFM). EV-D68 is often detected in patient respiratory samples but has also been detected in stool and wastewater, suggesting the potential for both respiratory and enteric routes of transmission. Here, we used a panel of EV-D68 isolates, including a historical pre-2014 isolate and multiple contemporary isolates from AFM outbreak years, to define the dynamics of viral replication and the host response to infection in primary human airway cells and stem cell-derived enteroids. We show that some recent EV-D68 isolates have decreased sensitivity to acid and temperature compared with earlier isolates and that the respiratory, but not intestinal, epithelium induces a robust type III interferon response that restricts infection. Our findings define the differential responses of the respiratory and intestinal epithelium to contemporary EV-D68 isolates and suggest that a subset of isolates have the potential to target both the human airway and gastrointestinal tracts.


Assuntos
Enterovirus Humano D/classificação , Células Epiteliais/fisiologia , Células Epiteliais/virologia , Linhagem Celular , Enterovirus Humano D/genética , Células Epiteliais/imunologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Intestinos/citologia , Pulmão/citologia , Organoides , Temperatura
18.
EBioMedicine ; 69: 103452, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34186485

RESUMO

BACKGROUND: Intestinal obstruction caused by intestinal fibrosis is a common and serious complication of Crohn's disease (CD). Intestinal fibroblasts, the main effector cells mediating gastrointestinal fibrosis, are activated during chronic inflammation. However, the mechanism of fibroblast activation in CD has not been well elucidated. METHODS: Fibroblasts isolated from stenotic and nonstenotic intestines of CD patients were used for RNA sequencing. Immunohistochemical and immunofluorescent staining was performed to evaluate the correlation between intestinal fibrosis and YAP/TAZ expression in our CD cohort and a DSS-induced chronic colitis murine model. A Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) inhibitor was used to explore the ROCK1-YAP/TAZ axis in intestinal fibroblasts in vitro and DSS-induced chronic colitis murine model in vivo. FINDINGS: The expression of YAP/TAZ was significantly upregulated in stenotic fibroblasts, which was associated with the YAP/TAZ target gene signature. YAP/TAZ knockdown suppressed the activation of intestinal fibroblasts. In intestinal fibroblasts, YAP/TAZ were activated by the Rho-ROCK1 signalling pathway. High YAP/TAZ expression was positively correlated with ROCK1 expression, which is a prognostic marker for intestinal obstruction in CD patients. INTERPRETATION: YAP/TAZ activation can lead to fibroblast activation and intestinal obstruction in CD. The effect of ROCK1 inhibitor on alleviating intestinal fibrosis is associated with YAP/TAZ inhibition. Targeted inhibition of YAP/TAZ in fibroblasts may be a potential therapeutic strategy to suppress intestinal fibrosis in CD. FUNDING: This work was supported by the National Key R&D Program of China (2019YFC1316002), the NSFC (81873547, 82073201, 81874177, 82000481) and the Shanghai Sailing Program (20YF1429400).


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doença de Crohn/metabolismo , Fibroblastos/metabolismo , Obstrução Intestinal/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Animais , Células Cultivadas , Doença de Crohn/complicações , Doença de Crohn/patologia , Feminino , Fibrose , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/patologia , Intestinos/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fatores de Transcrição/genética , Quinases Associadas a rho/metabolismo
19.
PLoS Genet ; 17(6): e1009607, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34081703

RESUMO

Early endosomes are the sorting hub on the endocytic pathway, wherein sorting nexins (SNXs) play important roles for formation of the distinct membranous microdomains with different sorting functions. Tubular endosomes mediate the recycling of clathrin-independent endocytic (CIE) cargoes back toward the plasma membrane. However, the molecular mechanism underlying the tubule formation is still poorly understood. Here we screened the effect on the ARF-6-associated CIE recycling endosomal tubules for all the SNX members in Caenorhabditis elegans (C. elegans). We identified SNX-3 as an essential factor for generation of the recycling tubules. The loss of SNX-3 abolishes the interconnected tubules in the intestine of C. elegans. Consequently, the surface and total protein levels of the recycling CIE protein hTAC are strongly decreased. Unexpectedly, depletion of the retromer components VPS-26/-29/-35 has no similar effect, implying that the retromer trimer is dispensable in this process. We determined that hTAC is captured by the ESCRT complex and transported into the lysosome for rapid degradation in snx-3 mutants. Interestingly, EEA-1 is increasingly recruited on early endosomes and localized to the hTAC-containing structures in snx-3 mutant intestines. We also showed that SNX3 and EEA1 compete with each other for binding to phosphatidylinositol-3-phosphate enriching early endosomes in Hela cells. Our data demonstrate for the first time that PX domain-only C. elegans SNX-3 organizes the tubular endosomes for efficient recycling and retrieves the CIE cargo away from the maturing sorting endosomes by competing with EEA-1 for binding to the early endosomes. However, our results call into question how SNX-3 couples the cargo capture and membrane remodeling in the absence of the retromer trimer complex.


Assuntos
Fatores de Ribosilação do ADP/genética , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Endossomos/metabolismo , Células Epiteliais/metabolismo , Nexinas de Classificação/genética , Proteínas de Transporte Vesicular/genética , Fatores de Ribosilação do ADP/metabolismo , Animais , Transporte Biológico , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Células Epiteliais/citologia , Regulação da Expressão Gênica , Células HeLa , Humanos , Intestinos/citologia , Lisossomos/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteólise , Transdução de Sinais , Nexinas de Classificação/deficiência , Proteínas de Transporte Vesicular/metabolismo
20.
Elife ; 102021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34137371

RESUMO

Sustained polarity and adhesion of epithelial cells is essential for the protection of our organs and bodies, and this epithelial integrity emerges during organ development amidst numerous programmed morphogenetic assaults. Using the developing Caenorhabditis elegans intestine as an in vivo model, we investigated how epithelia maintain their integrity through cell division and elongation to build a functional tube. Live imaging revealed that apical PAR complex proteins PAR-6/Par6 and PKC-3/aPkc remained apical during mitosis while apical microtubules and microtubule-organizing center (MTOC) proteins were transiently removed. Intestine-specific depletion of PAR-6, PKC-3, and the aPkc regulator CDC-42/Cdc42 caused persistent gaps in the apical MTOC as well as in other apical and junctional proteins after cell division and in non-dividing cells that elongated. Upon hatching, gaps coincided with luminal constrictions that blocked food, and larvae arrested and died. Thus, the apical PAR complex maintains apical and junctional continuity to construct a functional intestinal tube.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Células Epiteliais , Mucosa Intestinal , Animais , Caenorhabditis elegans , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Intestinos/citologia , Intestinos/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Centro Organizador dos Microtúbulos/metabolismo , Proteína Quinase C/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...