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1.
Nutrients ; 13(8)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34444954

RESUMO

L-Citrulline is a non-essential but still important amino acid that is released from enterocytes. Because plasma levels are reduced in case of impaired intestinal function, it has become a biomarker to monitor intestinal integrity. Moreover, oxidative stress induces protein citrullination, and antibodies against anti-citrullinated proteins are useful to monitor rheumatoid diseases. Citrullinated histones, however, may even predict a worse outcome in cancer patients. Supplementation of citrulline is better tolerated compared to arginine and might be useful to slightly improve muscle strength or protein balance. The following article shall provide an overview of L-citrulline properties and functions, as well as the current evidence for its use as a biomarker or as a therapeutic supplement.


Assuntos
Citrulinação/fisiologia , Citrulina/metabolismo , Suplementos Nutricionais , Enterócitos/metabolismo , Biomarcadores/metabolismo , Humanos , Força Muscular/efeitos dos fármacos , Proteostase/efeitos dos fármacos
2.
Science ; 373(6553)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34437091

RESUMO

The biogenesis of high-density lipoprotein (HDL) requires apoA1 and the cholesterol transporter ABCA1. Although the liver generates most of the HDL in the blood, HDL synthesis also occurs in the small intestine. Here, we show that intestine-derived HDL traverses the portal vein in the HDL3 subspecies form, in complex with lipopolysaccharide (LPS)-binding protein (LBP). HDL3, but not HDL2 or low-density lipoprotein, prevented LPS binding to and inflammatory activation of liver macrophages and instead supported extracellular inactivation of LPS. In mouse models involving surgical, dietary, or alcoholic intestinal insult, loss of intestine-derived HDL worsened liver injury, whereas outcomes were improved by therapeutics that elevated and depended upon raising intestinal HDL. Thus, protection of the liver from injury in response to gut-derived LPS is a major function of intestinally synthesized HDL.


Assuntos
Intestino Delgado/metabolismo , Lipoproteínas HDL3/metabolismo , Hepatopatias/prevenção & controle , Fígado/metabolismo , Veia Porta/metabolismo , Proteínas de Fase Aguda/metabolismo , Adulto , Animais , Proteínas de Transporte/metabolismo , HDL-Colesterol/sangue , HDL-Colesterol/metabolismo , Enterócitos/metabolismo , Humanos , Intestino Delgado/cirurgia , Macrófagos do Fígado/imunologia , Macrófagos do Fígado/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/metabolismo , Lipoproteínas HDL3/sangue , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Hepatopatias/patologia , Receptores X do Fígado/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
3.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360898

RESUMO

Previous studies have shown that microRNAs (miRNAs) are closely related to many viral infections. However, the molecular mechanism of how miRNAs regulate porcine epidemic diarrhea virus (PEDV) infection remains unclear. In this study, we first constructed a PEDV-infected IPEC-J2 cytopathic model to validate the relationship between miR-129a-3p expression levels and PEDV resistance. Secondly, we explored the effect of miR-129a-3p on PEDV infection by targeting the 3'UTR region of the ligand ectodysplasin (EDA) gene. Finally, transcriptome sequencing was used to analyze the downstream regulatory mechanism of EDA. The results showed that after 48 h of PEDV infection, IPEC-J2 cells showed obvious pathological changes, and miR-129a-3p expression was significantly downregulated (p < 0.01). Overexpression of miR-129a-3p mimics inhibited PEDV replication in IPEC-J2 cells; silencing endogenous miR-129a-3p can promote viral replication. A dual luciferase assay showed that miR-129a-3p could bind to the 3'UTR region of the EDA gene, which significantly reduced the expression level of EDA (p < 0.01). Functional verification showed that upregulation of EDA gene expression significantly promoted PEDV replication in IPEC-J2 cells. Overexpression of miR-129a-3p can activate the caspase activation and recruitment domain 11 (CARD11) mediated NF-κB pathway, thus inhibiting PEDV replication. The above results suggest that miR-129a-3p inhibits PEDV replication in IPEC-J2 cells by activating the NF-κB pathway by binding to the EDA 3'UTR region. Our results have laid the foundation for in-depth study of the mechanism of miR-129a-3p resistance and its application in porcine epidemic diarrhea disease-resistance breeding.


Assuntos
Infecções por Coronavirus/metabolismo , Ectodisplasinas/metabolismo , Enterócitos/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Vírus da Diarreia Epidêmica Suína/fisiologia , Transdução de Sinais/genética , Replicação Viral/genética , Regiões 3' não Traduzidas , Animais , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Regulação para Baixo/genética , Ectodisplasinas/genética , Enterócitos/virologia , Células HEK293 , Humanos , MicroRNAs/genética , Suínos , Transfecção , Regulação para Cima/genética , Células Vero , Sequenciamento Completo do Exoma/métodos
4.
Am J Physiol Cell Physiol ; 321(3): C471-C488, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34288721

RESUMO

Intestinal NaCl, HCO3-, and fluid absorption are strongly dependent on apical Na+/H+ exchange. The intestine expresses three presumably apical sodium-hydrogen exchanger (NHE) isoforms: NHE2, NHE3, and NHE8. We addressed the role of NHE8 [solute carrier 9A8 (SLC9A8)] and its interplay with NHE2 (SLC9A2) in luminal proton extrusion during acute and chronic enterocyte acidosis and studied the differential effects of NHE8 and NHE2 on enterocyte proliferation. In contrast to NHE3, which was upregulated in differentiated versus undifferentiated colonoids, the expression of NHE2 and NHE8 remained constant during differentiation of colonoids and Caco2Bbe cells. Heterogeneously expressed Flag-tagged rat (r)Nhe8 and human (h)NHE8 translocated to the apical membrane of Caco2Bbe cells. rNhe8 and hNHE8, when expressed in NHE-deficient PS120 fibroblasts showed higher sensitivity to HOE642 compared to NHE2. Lentiviral shRNA knockdown of endogenous NHE2 in Caco2Bbe cells (C2Bbe/shNHE2) resulted in a decreased steady-state intracellular pH (pHi), an increased NHE8 mRNA expression, and augmented NHE8-mediated apical NHE activity. Lentiviral shRNA knockdown of endogenous NHE8 in Caco2Bbe cells (C2Bbe/shNHE8) resulted in a decreased steady-state pHi as well, accompanied by decreased NHE2 mRNA expression and activity, which together contributed to reduced apical NHE activity in the NHE8-knockdown cells. Chronic acidosis increased NHE8 but not NHE2 mRNA expression. Alterations in NHE2 and NHE8 expression/activity affected proliferation, with C2Bbe/shNHE2 cells having lower and C2Bbe/shNHE8 having higher proliferative capacity, accompanied by amplified ERK1/2 signaling pathway and increased EGFR expression in the latter cell line. Thus, both Na+/H+ exchangers have distinct functions during cellular homeostasis by triggering different signaling pathways to regulate cellular proliferation and pHi control.


Assuntos
Colo/metabolismo , Enterócitos/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Colo/citologia , Colo/efeitos dos fármacos , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Guanidinas/farmacologia , Células HT29 , Homeostase/genética , Humanos , Concentração de Íons de Hidrogênio , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Organoides/citologia , Organoides/efeitos dos fármacos , Organoides/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Transdução de Sinais , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/metabolismo , Sulfonas/farmacologia
5.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207335

RESUMO

Several medical plants, such as Passiflora incarnata L., contain C-glycosylated flavonoids, which may contribute to their efficacy. Information regarding the bioavailability and metabolism of these compounds is essential, but not sufficiently available. Therefore, the metabolism of the C-glycosylated flavones orientin, isoorientin, schaftoside, isoschaftoside, vitexin, and isovitexin was investigated using the Caco-2 cell line as an in vitro intestinal and epithelial metabolism model. Isovitexin, orientin, and isoorientin showed broad ranges of phase I and II metabolites containing hydroxylated, methoxylated, and sulfated compounds, whereas schaftoside, isoschaftoside, and vitexin underwent poor metabolism. All metabolites were identified via UHPLC-MS or UHPLC-MS/MS using compound libraries containing all conceivable metabolites. Some structures were confirmed via UHPLC-MS experiments with reference compounds after a cleavage reaction using glucuronidase and sulfatase. Of particular interest is the observed cleavage of the C-C bonds between sugar and aglycone residues in isovitexin, orientin, and isoorientin, resulting in unexpected glucuronidated or sulfated luteolin and apigenin derivatives. These findings indicate that C-glycosidic flavones can be highly metabolized in the intestine. In particular, flavonoids with ortho-dihydroxy groups showed sulfated metabolites. The identified glucuronidated or sulfated aglycones demonstrate that enzymes expressed by Caco-2 cells are able to potentially cleave C-C bonds in vitro.


Assuntos
Flavonoides/metabolismo , Passiflora/química , Células CACO-2 , Enterócitos/metabolismo , Flavonoides/química , Humanos
6.
Nutrients ; 13(5)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063414

RESUMO

Intestinal iron transport requires an iron importer (Dmt1) and an iron exporter (Fpn1). The hormone hepcidin regulates iron absorption by modulating Fpn1 protein levels on the basolateral surface of duodenal enterocytes. In the genetic, iron-loading disorder hereditary hemochromatosis (HH), hepcidin production is low and Fpn1 protein expression is elevated. High Fpn1-mediated iron export depletes intracellular iron, causing a paradoxical increase in Dmt1-mediated iron import. Increased activity of both transporters causes excessive iron absorption, thus initiating body iron loading. Logically then, silencing of intestinal Dmt1 or Fpn1 could be an effective therapeutic intervention in HH. It was previously established that Dmt1 knock down prevented iron-loading in weanling Hamp (encoding hepcidin) KO mice (modeling type 2B HH). Here, we tested the hypothesis that Dmt1 silencing combined with dietary iron restriction (which may be recommended for HH patients) will mitigate iron loading once already established. Accordingly, adult Hamp KO mice were switched to a low-iron (LFe) diet and (non-toxic) folic acid-coupled, ginger nanoparticle-derived lipid vectors (FA-GDLVs) were used to deliver negative-control (NC) or Dmt1 siRNA by oral, intragastric gavage daily for 21 days. The LFe diet reduced body iron burden, and experimental interventions potentiated iron losses. For example, Dmt1 siRNA treatment suppressed duodenal Dmt1 mRNA expression (by ~50%) and reduced serum and liver non-heme iron levels (by ~60% and >85%, respectively). Interestingly, some iron-related parameters were repressed similarly by FA-GDLVs carrying either siRNA, including 59Fe (as FeCl3) absorption (~20% lower), pancreatic non-heme iron (reduced by ~65%), and serum ferritin (decreased 40-50%). Ginger may thus contain bioactive lipids that also influence iron homeostasis. In conclusion, the combinatorial approach of FA-GDLV and Dmt1 siRNA treatment, with dietary iron restriction, mitigated pre-existing iron overload in a murine model of HH.


Assuntos
Administração Oral , Gengibre/química , Hepcidinas/genética , Hepcidinas/metabolismo , Sobrecarga de Ferro/metabolismo , Ferro na Dieta/metabolismo , Nanopartículas/química , Fatores de Transcrição/metabolismo , Animais , Duodeno/metabolismo , Enterócitos/metabolismo , Ácido Fólico , Expressão Gênica , Hemocromatose/genética , Homeostase , Ferro/metabolismo , Sobrecarga de Ferro/genética , Lipídeos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/genética
7.
Nat Commun ; 12(1): 3339, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099655

RESUMO

The intestinal epithelium is a complex structure that integrates digestive, immunological, neuroendocrine, and regenerative functions. Epithelial homeostasis is maintained by a coordinated cross-talk of different epithelial cell types. Loss of integrity of the intestinal epithelium plays a key role in inflammatory diseases and gastrointestinal infection. Here we show that the intestine-enriched miR-802 is a central regulator of intestinal epithelial cell proliferation, Paneth cell function, and enterocyte differentiation. Genetic ablation of mir-802 in the small intestine of mice leads to decreased glucose uptake, impaired enterocyte differentiation, increased Paneth cell function and intestinal epithelial proliferation. These effects are mediated in part through derepression of the miR-802 target Tmed9, a modulator of Wnt and lysozyme/defensin secretion in Paneth cells, and the downstream Wnt signaling components Fzd5 and Tcf4. Mutant Tmed9 mice harboring mutations in miR-802 binding sites partially recapitulate the augmented Paneth cell function of mice lacking miR-802. Our study demonstrates a broad miR-802 network that is important for the integration of signaling pathways of different cell types controlling epithelial homeostasis in the small intestine.


Assuntos
Diferenciação Celular/fisiologia , Enterócitos/metabolismo , Intestino Delgado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Celulas de Paneth/metabolismo , Animais , Proliferação de Células , Feminino , Receptores Frizzled/metabolismo , Expressão Gênica , Células HEK293 , Homeostase/fisiologia , Humanos , Mucosa Intestinal/metabolismo , Intestinos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Salmonella typhimurium , Fator de Transcrição 4/metabolismo , Transcriptoma , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Via de Sinalização Wnt
8.
Am J Physiol Gastrointest Liver Physiol ; 321(1): G75-G86, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34009042

RESUMO

The absorptive cells of the small intestine, namely, enterocytes, contribute to postprandial blood lipid levels by secreting dietary triacylglycerol in chylomicrons. The rate and amount of dietary triacylglycerol absorbed vary along the length of the small intestine. Excess dietary triacylglycerol not immediately secreted in chylomicrons can be temporarily stored in cytoplasmic lipid droplets (CLDs) and repackaged in chylomicrons at later times. The characteristics of CLDs, including their size, number per cell, and associated proteins, may influence CLD metabolism and reflect differences in lipid processing or storage in each intestinal region. However, it is unknown whether the characteristics or proteomes of CLDs differ in enterocytes of each intestine region in response to dietary fat. Furthermore, it is unclear if obesity influences the characteristics or proteomes of CLDs in each intestine region. To address this, we used transmission electron microscopy and shotgun liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis to assess the characteristics and proteome of CLDs in the proximal, middle, and distal regions of the small intestine of lean and diet-induced obese (DIO) mice 2 h after an oil gavage. We identified differences in lipid storage along the length of the small intestine and between lean and DIO mice, as well as distinct CLD proteomes reflecting potentially unique roles of CLDs in each region. This study reveals differences in lipid processing along the length of the small intestine in response to dietary fat in lean and DIO mice and reflects distinct features of the proximal, middle, distal region of the small intestine.NEW & NOTEWORTHY This study reflects the dynamics of fat absorption along the length of the small intestine in lean and obese mice in the physiological response to dietary fat. We identified unique features of cytoplasmic lipid droplets (CLDs) in the proximal, middle, and distal regions of the small intestine of lean and obese mice that may contribute to regional differences in dietary fat processing, absorption, or CLD metabolism.


Assuntos
Gorduras na Dieta/metabolismo , Intestino Delgado/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Animais , Citosol/metabolismo , Enterócitos/metabolismo , Intestinos , Camundongos , Triglicerídeos/metabolismo
9.
Infect Genet Evol ; 92: 104892, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33957338

RESUMO

Novel coronavirus SARS-CoV-2 was recently outbreak worldwide causes severe acute respiratory syndrome along with gastrointestinal symptoms for some infected patients. Information on detail pathogenesis, host immune responses and responsible biological pathways are limited. Therefore, infection specific host gut responses and dietary supplements to neutralize immune inflammation demand extensive research. This study aimed to find differences in global co-expression protein-protein interaction sub-network and enriched biological processes in SARS-CoV and SARS-CoV-2 infected gut enterocytes cell line. Attempts have also been made to predict some dietary supplements to boost human health. The SARS-CoV and SARS-CoV-2 infected differential express proteins were integrated with the human protein interaction network and co-expression subnetworks were constructed. Common hubs of these sub-networks reshape central cellular pathways of metabolic processes, lipid localization, hypoxia response to decrease oxygen level and transport of bio-molecules. The major biological process enriched in the unique hub of SARS-CoV-2 significantly differ from SARS-CoV, related to interferon signaling, regulation of viral process and influenza-A enzymatic pathway. Predicted dietary supplements can improve SARS-CoV-2 infected person''s health by boosting the host immunity/reducing inflammation. To the best of our knowledge this is the first report on co-expression network mediated biological process in human gut enterocytes to predict dietary supplements/compounds.


Assuntos
COVID-19/virologia , Enterócitos/metabolismo , Enterócitos/virologia , Vírus da SARS/metabolismo , SARS-CoV-2/metabolismo , Suplementos Nutricionais , Regulação da Expressão Gênica , Humanos , Mapas de Interação de Proteínas , RNA-Seq , Vírus da SARS/genética , SARS-CoV-2/genética
10.
Commun Biol ; 4(1): 631, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045640

RESUMO

IL22 is an important cytokine involved in the intestinal defense mechanisms against microbiome. By using ileum-derived organoids, we show that the expression of anti-microbial peptides (AMPs) and anti-viral peptides (AVPs) can be induced by IL22. In addition, we identified a bacterial and a viral route, both leading to IL22 production by T cells, but via different pathways. Bacterial products, such as LPS, induce enterocyte-secreted SAA1, which triggers the secretion of IL6 in fibroblasts, and subsequently IL22 in T cells. This IL22 induction can then be enhanced by macrophage-derived TNFα in two ways: by enhancing the responsiveness of T cells to IL6 and by increasing the expression of IL6 by fibroblasts. Viral infections of intestinal cells induce IFNß1 and subsequently IL7. IFNß1 can induce the expression of IL6 in fibroblasts and the combined activity of IL6 and IL7 can then induce IL22 expression in T cells. We also show that IL22 reduces the expression of viral entry receptors (e.g. ACE2, TMPRSS2, DPP4, CD46 and TNFRSF14), increases the expression of anti-viral proteins (e.g. RSAD2, AOS, ISG20 and Mx1) and, consequently, reduces the viral infection of neighboring cells. Overall, our data indicates that IL22 contributes to the innate responses against both bacteria and viruses.


Assuntos
Interleucinas/biossíntese , Interleucinas/metabolismo , Animais , Antibacterianos/metabolismo , Antivirais/metabolismo , Técnicas de Cultura de Células , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Enterócitos/imunologia , Enterócitos/metabolismo , Feminino , Fibroblastos/imunologia , Fibroblastos/metabolismo , Interleucinas/imunologia , Mucosa Intestinal/metabolismo , Intestinos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/imunologia , Células Mieloides/metabolismo , Organoides/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/metabolismo
11.
Mol Biol Rep ; 48(5): 4667-4675, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34023987

RESUMO

The transmembrane protease serine 2 (TMPRSS2) is a membrane anchored protease that primarily expressed by epithelial cells of respiratory and gastrointestinal systems and has been linked to multiple pathological processes in humans including tumor growth, metastasis and viral infections. Recent studies have shown that TMPRSS2 expressed on cell surface of host cells could play a crucial role in activation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein which facilitates the rapid early entry of the virus into host cells. In addition, direct suppression of TMPRSS2 using small drug inhibitors has been demonstrated to be effective in decreasing SARS-CoV-2 infection in vitro, which presents TMPRSS2 protease as a potential therapeutic strategy for SARS-CoV-2 infection. Recently, SARS-CoV-2 has been shown to be capable of infecting gastrointestinal enterocytes and to provoke gastrointestinal disorders in patients with COVID-19 disease, which is considered as a new transmission route and target organ of SARS-CoV-2. In this review, we highlight the biochemical properties of TMPRSS2 protease and discuss the potential targeting of TMPRSS2 by inhibitors to prevent the SARS-CoV-2 spreading through gastro-intestinal tract system as well as the hurdles that need to be overcome.


Assuntos
COVID-19/metabolismo , Enterócitos/efeitos dos fármacos , SARS-CoV-2/fisiologia , Serina Endopeptidases/metabolismo , Inibidores de Serino Proteinase/farmacologia , Antivirais/farmacologia , COVID-19/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Enterócitos/metabolismo , Enterócitos/virologia , Humanos , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos
12.
Nat Commun ; 12(1): 3074, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031373

RESUMO

Single-cell RNA sequencing combined with spatial information on landmark genes enables reconstruction of spatially-resolved tissue cell atlases. However, such approaches are challenging for rare cell types, since their mRNA contents are diluted in the spatial transcriptomics bulk measurements used for landmark gene detection. In the small intestine, enterocytes, the most common cell type, exhibit zonated expression programs along the crypt-villus axis, but zonation patterns of rare cell types such as goblet and tuft cells remain uncharacterized. Here, we present ClumpSeq, an approach for sequencing small clumps of attached cells. By inferring the crypt-villus location of each clump from enterocyte landmark genes, we establish spatial atlases for all epithelial cell types in the small intestine. We identify elevated expression of immune-modulatory genes in villus tip goblet and tuft cells and heterogeneous migration patterns of enteroendocrine cells. ClumpSeq can be applied for reconstructing spatial atlases of rare cell types in other tissues and tumors.


Assuntos
Transporte Biológico/genética , Transporte Biológico/fisiologia , Biologia Computacional/métodos , Intestinos/fisiologia , Animais , Diferenciação Celular , Enterócitos/metabolismo , Células Enteroendócrinas/metabolismo , Células Epiteliais/metabolismo , Epitélio , Expressão Gênica , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Análise de Sequência de RNA
13.
Mar Drugs ; 19(5)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946805

RESUMO

Fish vary in their ability to biosynthesise long-chain polyunsaturated fatty acids (LC-PUFA) depending upon the complement and function of key enzymes commonly known as fatty acyl desaturases and elongases. It has been reported in Solea senegalensis the existence of a Δ4 desaturase, enabling the biosynthesis of docosahexaenoic acid (DHA) from eicosapentaenoic acid (EPA), which can be modulated by the diet. The present study aims to evaluate the combined effects of the partial replacement of fish oil (FO) with vegetable oils and reduced environmental salinity in the fatty acid composition of relevant body compartments (muscle, hepatocytes and enterocytes), the enzymatic activity over α-linolenic acid (ALA) to form n-3 LC-PUFA through the incubation of isolated hepatocytes and enterocytes with [1-14C] 18:3 n-3, and the regulation of the S. senegalensis fads2 and elovl5 in the liver and intestine. The presence of radiolabelled products, including 18:4n-3, 20:4n-3 and EPA, provided compelling evidence that a complete pathway enabling the biosynthesis of EPA from ALA, establishing S. senegalensis, has at least one Fads2 with ∆6 activity. Dietary composition prevailed over salinity in regulating the expression of fads2, while salinity did so over dietary composition for elovl5. FO replacement enhanced the proportion of DHA in S. senegalensis muscle and the combination with 20 ppt salinity increased the amount of n-3 LC-PUFA in hepatocytes.


Assuntos
Gorduras na Dieta/metabolismo , Ecossistema , Ácidos Graxos Ômega-3/biossíntese , Óleos de Peixe/metabolismo , Linguados/metabolismo , Óleos Vegetais/metabolismo , Ração Animal , Animais , Aquicultura , Gorduras na Dieta/administração & dosagem , Enterócitos/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Óleos de Peixe/administração & dosagem , Hepatócitos/metabolismo , Músculos/metabolismo , Óleos Vegetais/administração & dosagem , Salinidade , Fatores de Tempo , Água/química
14.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807969

RESUMO

Sitosterolemia is a lipid disorder characterized by the accumulation of dietary xenosterols in plasma and tissues caused by mutations in either ABCG5 or ABCG8. ABCG5 ABCG8 encodes a pair of ABC half transporters that form a heterodimer (G5G8), which then traffics to the surface of hepatocytes and enterocytes and promotes the secretion of cholesterol and xenosterols into the bile and the intestinal lumen. We review the literature from the initial description of the disease, the discovery of its genetic basis, current therapy, and what has been learned from animal, cellular, and molecular investigations of the transporter in the twenty years since its discovery. The genomic era has revealed that there are far more carriers of loss of function mutations and likely pathogenic variants of ABCG5 ABCG8 than previously thought. The impact of these variants on G5G8 structure and activity are largely unknown. We propose a classification system for ABCG5 ABCG8 mutants based on previously published systems for diseases caused by defects in ABC transporters. This system establishes a framework for the comprehensive analysis of disease-associated variants and their impact on G5G8 structure-function.


Assuntos
Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Colesterol/metabolismo , Hipercolesterolemia , Enteropatias , Erros Inatos do Metabolismo Lipídico , Lipoproteínas , Mutação , Fitosteróis/efeitos adversos , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/história , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/história , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Enterócitos/metabolismo , Enterócitos/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , História do Século XXI , Humanos , Hipercolesterolemia/genética , Hipercolesterolemia/história , Hipercolesterolemia/metabolismo , Hipercolesterolemia/patologia , Enteropatias/genética , Enteropatias/história , Enteropatias/metabolismo , Enteropatias/patologia , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/história , Erros Inatos do Metabolismo Lipídico/metabolismo , Erros Inatos do Metabolismo Lipídico/patologia , Lipoproteínas/genética , Lipoproteínas/história , Lipoproteínas/metabolismo , Fitosteróis/genética , Fitosteróis/história , Fitosteróis/metabolismo
15.
Int J Mol Sci ; 22(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925597

RESUMO

Iron is a critical metal for several vital biological processes. Most of the body's iron is bound to hemoglobin in erythrocytes. Iron from senescent red blood cells is recycled by macrophages in the spleen, liver and bone marrow. Dietary iron is taken up by the divalent metal transporter 1 (DMT1) in enterocytes and transported to portal blood via ferroportin (FPN), where it is bound to transferrin and taken up by hepatocytes, macrophages and bone marrow cells via transferrin receptor 1 (TfR1). While most of the physiologically active iron is bound hemoglobin, the major storage of most iron occurs in the liver in a ferritin-bound fashion. In response to an increased iron load, hepatocytes secrete the peptide hormone hepcidin, which binds to and induces internalization and degradation of the iron transporter FPN, thus controlling the amount of iron released from the cells into the blood. This review summarizes the key mechanisms and players involved in cellular and systemic iron regulation.


Assuntos
Ferro/metabolismo , Ferro/fisiologia , Animais , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Enterócitos/metabolismo , Ferritinas/metabolismo , Hemoglobinas/metabolismo , Hepatócitos/metabolismo , Humanos , Ferro na Dieta/metabolismo , Fígado/metabolismo , Receptores da Transferrina/metabolismo , Baço/metabolismo , Transferrina/metabolismo
16.
Int J Mol Sci ; 22(7)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916868

RESUMO

MicroRNAs (miRNAs) are small RNAs present in extracellular vesicles (EVs) that, when transferred to a target cell, affect its biological functions. Plant miRNAs regulate the expression of certain mammalian genes. Here, we characterized EVs in fruit and vegetable juice, and their miRNA cargo, and investigated whether such miRNA-containing EVs could be taken up by mammalian enterocytes in vitro. Using filtration and ultra-centrifugation methods, EVs were purified from commercially available and manually squeezed plant juice. EV morphological features and subcellular localization were analyzed using the NanoSight tracking system and electron microscopy. Plant EV miRNA levels were evaluated using quantitative reverse transcription PCR. For the in vitro EV uptake experiments, rat intestinal epithelial cells (IEC6) were used. Plant EVs shared morphological features with mammalian EVs and contained miR156a-5p, miR166a-3p, and miR168a-5p. EVs were present in the cell sap-filled central vacuoles and were taken up by IEC6 cells. Edible plant cells produce EVs that contain various miRNAs and release them into the central vacuole. The exogenous plant EVs are taken up by mammalian enterocytes in vitro. These findings suggest the possibility that exogenous plant miRNAs carried by EVs can be absorbed via the gastrointestinal tract.


Assuntos
Enterócitos/metabolismo , Exossomos/química , Sucos de Frutas e Vegetais , MicroRNAs , Nanopartículas , Animais , Linhagem Celular , Enterócitos/citologia , MicroRNAs/farmacocinética , MicroRNAs/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Ratos
17.
Int J Mol Sci ; 22(8)2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920650

RESUMO

Electrolytes (NaCl) and fluid malabsorption cause diarrhea in inflammatory bowel disease (IBD). Coupled NaCl absorption, mediated by Na+/H+ and Cl-/HCO3- exchanges on the intestinal villus cells brush border membrane (BBM), is inhibited in IBD. Arachidonic acid metabolites (AAMs) formed via cyclooxygenase (COX) or lipoxygenase (LOX) pathways are elevated in IBD. However, their effects on NaCl absorption are not known. We treated SAMP1/YitFc (SAMP1) mice, a model of spontaneous ileitis resembling human IBD, with Arachidonyl Trifluoro Methylketone (ATMK, AAM inhibitor), or with piroxicam or MK-886, to inhibit COX or LOX pathways, respectively. Cl-/HCO3- exchange, measured as DIDS-sensitive 36Cl uptake, was significantly inhibited in villus cells and BBM vesicles of SAMP1 mice compared to AKR/J controls, an effect reversed by ATMK. Piroxicam, but not MK-886, also reversed the inhibition. Kinetic studies showed that inhibition was secondary to altered Km with no effects on Vmax. Whole cell or BBM protein levels of Down-Regulated in Adenoma (SLC26A3) and putative anion transporter-1 (SLC26A6), the two key BBM Cl-/HCO3- exchangers, were unaltered. Thus, inhibition of villus cell Cl-/HCO3- exchange by COX pathway AAMs, such as prostaglandins, via reducing the affinity of the exchanger for Cl-, and thereby causing NaCl malabsorption, could significantly contribute to IBD-associated diarrhea.


Assuntos
Ácidos Araquidônicos/metabolismo , Antiportadores de Cloreto-Bicarbonato/metabolismo , Enterócitos/metabolismo , Ileíte/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Ácidos Araquidônicos/farmacologia , Células Cultivadas , Antiportadores de Cloreto-Bicarbonato/antagonistas & inibidores , Inibidores de Ciclo-Oxigenase/farmacologia , Enterócitos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Ileíte/genética , Indóis/farmacologia , Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/farmacologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Piroxicam/farmacologia
18.
Elife ; 102021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724181

RESUMO

Tissue homeostasis requires long-term lineage fidelity of somatic stem cells. Whether and how age-related changes in somatic stem cells impact the faithful execution of lineage decisions remains largely unknown. Here, we address this question using genome-wide chromatin accessibility and transcriptome analysis as well as single-cell RNA-seq to explore stem-cell-intrinsic changes in the aging Drosophila intestine. These studies indicate that in stem cells of old flies, promoters of Polycomb (Pc) target genes become differentially accessible, resulting in the increased expression of enteroendocrine (EE) cell specification genes. Consistently, we find age-related changes in the composition of the EE progenitor cell population in aging intestines, as well as a significant increase in the proportion of EE-specified intestinal stem cells (ISCs) and progenitors in aging flies. We further confirm that Pc-mediated chromatin regulation is a critical determinant of EE cell specification in the Drosophila intestine. Pc is required to maintain expression of stem cell genes while ensuring repression of differentiation and specification genes. Our results identify Pc group proteins as central regulators of lineage identity in the intestinal epithelium and highlight the impact of age-related decline in chromatin regulation on tissue homeostasis.


Assuntos
Células-Tronco Adultas/metabolismo , Linhagem da Célula/genética , Proteínas de Drosophila/genética , Intestinos/citologia , Proteínas do Grupo Polycomb/genética , Envelhecimento/genética , Animais , Diferenciação Celular/genética , Cromatina/genética , Cromatina/metabolismo , Drosophila/genética , Proteínas de Drosophila/metabolismo , Enterócitos/metabolismo , Células Enteroendócrinas/metabolismo , Regulação da Expressão Gênica , Homeostase , Mucosa Intestinal/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Transcriptoma
19.
Am J Physiol Cell Physiol ; 320(6): C1042-C1054, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33788631

RESUMO

Intestinal Tuft cells sense luminal contents to influence the mucosal immune response against eukaryotic infection. Paneth cells secrete antimicrobial proteins as part of the mucosal protective barrier. Defects in Tuft and Paneth cells occur commonly in various gut mucosal disorders. MicroRNA-195 (miR-195) regulates the stability and translation of target mRNAs and is involved in many aspects of cell processes and pathologies. Here, we reported the posttranscriptional mechanisms by which miR-195 regulates Tuft and Paneth cell function in the small intestinal epithelium. Mucosal tissues from intestinal epithelial tissue-specific miR-195 transgenic (miR195-Tg) mice had reduced numbers of double cortin-like kinase 1 (DCLK1)-positive (Tuft) and lysozyme-positive (Paneth) cells, compared with tissues from control mice, but there were no effects on Goblet cells and enterocytes. Intestinal organoids expressing higher miR-195 levels from miR195-Tg mice also exhibited fewer Tuft and Paneth cells. Transgenic expression of miR-195 in mice failed to alter growth of the small intestinal mucosa but increased vulnerability of the gut barrier in response to lipopolysaccharide (LPS). Studies aimed at investigating the mechanism underlying regulation of Tuft cells revealed that miR-195 directly interacted with the Dclk1 mRNA via its 3'-untranslated region and inhibited DCLK1 translation. Interestingly, the RNA-binding protein HuR competed with miR-195 for binding Dclk1 mRNA and increased DCLK1 expression. These results indicate that miR-195 suppresses the function of Tuft and Paneth cells in the small intestinal epithelium and further demonstrate that increased miR-195 disrupts Tuft cell function by inhibiting DCLK1 translation via interaction with HuR.


Assuntos
Mucosa Intestinal/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Células CACO-2 , Linhagem Celular , Linhagem Celular Tumoral , Enterócitos/metabolismo , Feminino , Células Caliciformes/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Organoides/metabolismo
20.
Ann Clin Lab Sci ; 51(1): 131-135, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33653792

RESUMO

Adenocarcinoma with enteroblastic differentiation is an extremely rare tumor with poor prognosis and unique pathologic features. The tumor appears to be relatively more common in stomach, with rare cases reported in esophagus, colon, rectum and ampulla. Underrecognition by pathologists may be a contributing factor towards underreporting of this tumor. Combination of carcinosarcoma and enteroblastic differentiation has not been reported so far.We report a unique case of ampullary carcinosarcoma with enteroblastic differentiation in a 59-year-old female, diagnosed in the pancreatoduodenectomy specimen. The carcinomatous component showed features of enteroblastic differentiation characterized by tubular architecture with clear cytoplasm, solid component with trabecular architecture and immunohistochemical expression of SALL4 and AFP. The patient was treated with adjuvant Folfirinox chemotherapy and is disease free at 17 months follow up.


Assuntos
Carcinossarcoma/diagnóstico , Carcinossarcoma/fisiopatologia , Mucosa Intestinal/citologia , Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Diferenciação Celular/genética , Enterócitos/metabolismo , Enterócitos/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Pancreaticoduodenectomia/métodos , Neoplasias Gástricas/patologia
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