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1.
J Oleo Sci ; 69(9): 1077-1085, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788520

RESUMO

There is growing research interest in the hypocholesterolemic effect of various food components such as polyphenols. In this study, we examined the effects of oligonol-a low-molecular weight polyphenol extracted from lychee fruit-on cholesterol metabolism in rats under short-term administration. Administration of oligonol for 3 days significantly increased cecum weight and decreased cecal n-butyric acid concentrations in rats. Oligonol also significantly lowered the levels of hepatic cholesterol and increased the levels of total neutral steroids excreted in the feces. It also increased fecal ß-muricholic acid significantly, whereas the levels of total acidic steroids remained unchanged. Gene expression of hepatic CYP7A1 (cytochrome P450 family 7 subfamily A member 1) significantly increased following the administration of oligonol. This increase could be ascribed to changes in the expression of farnesoid X receptor, small heterodimer partner, and fibroblast growth factor 15 in ileum. Our data suggest that oligonol induces hypocholesterolemic effects through the inhibition of biliary cholesterol absorption from the intestine and the upregulation of cholesterol catabolism in rats even following short-term administration. Therefore, oligonol may be an important food component for reducing cholesterol level.


Assuntos
Catequina/análogos & derivados , Colesterol/metabolismo , Litchi/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Animais , Butiratos/metabolismo , Catequina/administração & dosagem , Catequina/isolamento & purificação , Catequina/farmacologia , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Expressão Gênica/efeitos dos fármacos , Íleo/metabolismo , Fígado/metabolismo , Masculino , Peso Molecular , Fenóis/administração & dosagem , Polifenóis , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Tempo
2.
Nature ; 584(7821): 415-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641829

RESUMO

Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences1-3. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases4. Here we report that steroid signalling in Drosophila from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.


Assuntos
Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Intestinos/crescimento & desenvolvimento , Longevidade/fisiologia , Tamanho do Órgão/fisiologia , Ovário/metabolismo , Esteroides/metabolismo , Envelhecimento , Animais , Carcinogênese , Proliferação de Células , Copulação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Ecdisona/metabolismo , Feminino , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/anatomia & histologia , Intestinos/citologia , Intestinos/patologia , Masculino , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
3.
Nat Commun ; 11(1): 3306, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620754

RESUMO

The endoplasmic reticulum (ER) is selectively degraded by autophagy (ER-phagy) through proteins called ER-phagy receptors. In Saccharomyces cerevisiae, Atg40 acts as an ER-phagy receptor to sequester ER fragments into autophagosomes by binding Atg8 on forming autophagosomal membranes. During ER-phagy, parts of the ER are morphologically rearranged, fragmented, and loaded into autophagosomes, but the mechanism remains poorly understood. Here we find that Atg40 molecules assemble in the ER membrane concurrently with autophagosome formation via multivalent interaction with Atg8. Atg8-mediated super-assembly of Atg40 generates highly-curved ER regions, depending on its reticulon-like domain, and supports packing of these regions into autophagosomes. Moreover, tight binding of Atg40 to Atg8 is achieved by a short helix C-terminal to the Atg8-family interacting motif, and this feature is also observed for mammalian ER-phagy receptors. Thus, this study significantly advances our understanding of the mechanisms of ER-phagy and also provides insights into organelle fragmentation in selective autophagy of other organelles.


Assuntos
Autofagossomos/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Família da Proteína 8 Relacionada à Autofagia/química , Família da Proteína 8 Relacionada à Autofagia/genética , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia/química , Proteínas Relacionadas à Autofagia/genética , Sítios de Ligação/genética , Estresse do Retículo Endoplasmático/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Mutação , Ligação Proteica , Domínios Proteicos , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
4.
Am J Physiol Gastrointest Liver Physiol ; 319(2): G212-G226, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32597709

RESUMO

Short bowel syndrome (SBS) is associated with changes in the intestinal microbiome and marked local and systemic inflammation. There is also a late complication of SBS, intestinal failure associated liver disease (IFALD) in which hepatic steatosis progresses to cirrhosis. Most patients with SBS arrive at massive intestinal resection after a contaminating intraabdominal catastrophe and have a history of exposure to broad-spectrum antibiotics. We therefore investigated whether the administration of broad-spectrum antibiotics in conjunction with SBS in zebrafish (ZF) would replicate these systemic effects observed in humans to identify potentially druggable targets to aid in the management of SBS and resulting IFALD. In zebrafish with SBS, broad-spectrum antibiotics altered the microbiome, decreased inflammation, and reduced the development of hepatic steatosis. After two weeks of broad-spectrum antibiotics, these fish exhibited decreased alpha diversity, with less variation in microbial community composition between SBS and sham fish. Additionally, administration of broad-spectrum antibiotics was associated with decreased expression of intestinal toll-like receptor 4 (tlr4), increased expression of the intestinal gene encoding the Farnesoid X receptor (fxr), decreased expression of downstream hepatic cyp7a1, and decreased development of hepatic steatosis. SBS in zebrafish reproducibly results in increased epithelial surface area as occurs in human patients who demonstrate intestinal adaptation, but antibiotic administration in zebrafish with SBS reduced these gains with increased cell death in the intervillus pocket that contains stem/progenitor cells. These alternate states in SBS zebrafish might direct the development of future human therapies.NEW & NOTEWORTHY In a zebrafish model that replicates a common clinical scenario, systemic effects of the administration of broad-spectrum antibiotics in a zebrafish model of SBS identified two alternate states that led to the establishment of fat accumulation in the liver or its absence. Broad-spectrum antibiotics given to zebrafish with SBS over 2 wk altered the intestinal microbiome, decreased intestinal and hepatic inflammation, and decreased hepatic steatosis.


Assuntos
Antibacterianos/farmacologia , Fígado Gorduroso/prevenção & controle , Receptores Citoplasmáticos e Nucleares/metabolismo , Síndrome do Intestino Curto/microbiologia , Animais , Peixe-Zebra
5.
Toxicology ; 441: 152522, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32534104

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are organic chemicals with wide industrial and consumer uses. They are found ubiquitously at low levels in the environment and are detectable in humans and wildlife. Perfluorobutane Sulfonate (PFBS) is a short-chained PFAS used to replace perfluorooctane sulfonate in commerce. In general, the rate of clearance for the short-chained PFAS is faster than that for the long-chained congeners. This study evaluated the pharmacokinetic properties of PFBS and its hepatic transcriptional responses in CD-1 mice. Males and females were given PFBS by oral gavage at 30 or 300 mg/kg; controls received 0.5 % Tween-20 vehicle. Trunk blood was collected at 0.5, 1, 2, 4, 8, 16 and 24 h thereafter; liver and kidney were also harvested. Serum and tissue concentrations of PFBS were determined by HPLC-MS-MS. Expression of several hepatic nuclear receptor target genes was determined by qPCR. The half-life of PFBS was estimated as 5.8 h in the males and 4.5 h in the females. Tmax was reached within 1-2 h. Volume of distribution was similar between the two sexes (0.32-0.40 L/kg). The rate of PFBS clearance was linear with exposure doses. Within 24 h, serum PFBS declined to less than 5 % of Cmax. PFBS was detected in liver or kidney, although tissue levels of the chemical were only a fraction of those in serum. At 24 h after administration of 300 mg/kg PFBS, elevated expression of several hepatic genes targeted for PPARα, PPARy, and PXR but not by AhR, LXR or CAR was observed, with responses indistinguishable between males and females. Little to no transcriptional response was seen with the 30 mg/kg dose. The short serum half-lives of PFBS (4-5 h) in mice were comparable to those reported in rats. Although detection of PFBS in liver was low compared to that in serum even at the 300 mg/kg dose, the tissue level was sufficient to activate several hepatic nuclear receptors, which may represent an acute response to the chemical at a high dose.


Assuntos
Fluorcarbonetos/farmacocinética , Fígado/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Ácidos Sulfônicos/farmacocinética , Animais , Relação Dose-Resposta a Droga , Feminino , Meia-Vida , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/metabolismo , Masculino , Taxa de Depuração Metabólica , Camundongos , Reação em Cadeia da Polimerase , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores Sexuais , Transcriptoma/efeitos dos fármacos
6.
Toxicol Appl Pharmacol ; 399: 115055, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32428594

RESUMO

The liver cell line HepaRG is one of the preferred sources of human hepatocytes for in vitro applications. However, mitochondrial energy metabolism is relatively low, which affects hepatic functionality and sensitivity to hepatotoxins. Culturing in a bioartificial liver (BAL) system with high oxygen, medium perfusion, low substrate stiffness, and 3D conformation increases HepaRG functionality and mitochondrial activity compared to conventional monolayer culturing. In addition, drug metabolism has been improved by overexpression of the constitutive androstane receptor (CAR), a regulator of drug and energy metabolism in the new HepaRG-CAR line. Here, we investigated the effect of BAL culturing on the HepaRG-CAR line by applying a simple and downscaled BAL culture procedure based on shaking 3D cultures, named Bal-in-a-dish (BALIAD). We compared monolayer and BALIAD cultures of HepaRG and HepaRG-CAR cells. CAR overexpression and BALIAD culturing synergistically or additively increased transcript levels of CAR and three of the seven tested CAR target genes in biotransformation. Additionally, Cytochrome P450 3A4 activity was 35-fold increased. The mitochondrial energy metabolism was enhanced; lactate production and glucose consumption switched into lactate elimination and glucose production. BALIAD culturing alone reduced glycogen content and increased oxygen consumption and mitochondrial content. Both CAR overexpression and BALIAD culturing decreased mitochondrial superoxide levels. HepaRG-CAR BALIADs were most sensitive to mitochondrial toxicity induced by the hepatotoxin amiodarone, as indicated by oxygen consumption and mitochondrial superoxide accumulation. These data show that BALIAD culturing of HepaRG-CAR cells induces high mitochondrial energy metabolism and xenobiotic metabolism, increasing its potential for drug toxicity studies.


Assuntos
Amiodarona/farmacologia , Biotransformação/fisiologia , Hepatócitos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/metabolismo , Técnicas de Cultura de Células/métodos , Linhagem Celular , Metabolismo Energético/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado Artificial , Mitocôndrias/metabolismo
7.
Psychopharmacology (Berl) ; 237(7): 2055-2073, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32472163

RESUMO

RATIONALE: The nuclear receptor retinoid X receptor (RXR) belongs to a nuclear receptor superfamily that modulates diverse functions via homodimerization with itself or several other nuclear receptors, including PPARα. While the activation of PPARα by natural or synthetic agonists regulates the sleep-wake cycle, the role of RXR in the sleep modulation is unknown. OBJECTIVES: We investigated the effects of bexarotene (Bexa, a RXR agonist) or UVI 3003 (UVI, a RXR antagonist) on sleep, sleep homeostasis, levels of neurochemical related to sleep modulation, and c-Fos and NeuN expression. METHODS: The sleep-wake cycle and sleep homeostasis were analyzed after application of Bexa or UVI. Moreover, we also evaluated whether Bexa or UVI could induce effects on dopamine, serotonin, norepinephrine epinephrine, adenosine, and acetylcholine contents, collected from either the nucleus accumbens or basal forebrain. In addition, c-Fos and NeuN expression in the hypothalamus was determined after Bexa or UVI treatments. RESULTS: Systemic application of Bexa (1 mM, i.p.) attenuated slow-wave sleep and rapid eye movement sleep. In addition, Bexa increased the levels of dopamine, serotonin, norepinephrine epinephrine, adenosine, and acetylcholine sampled from either the nucleus accumbens or basal forebrain. Moreover, Bexa blocked the sleep rebound period after total sleep deprivation, increased in the hypothalamus the expression of c-Fos, and decreased NeuN activity. Remarkably, UVI 3003 (1 mM, i.p.) induced opposite effects in sleep, sleep homeostasis, neurochemicals levels, and c-Fos and NeuN activity. CONCLUSIONS: The administration of RXR agonist or antagonist significantly impaired the sleep-wake cycle and exerted effects on the levels of neurochemicals related to sleep modulation. Moreover, Bexa or UVI administration significantly affected c-Fos and NeuN expression in the hypothalamus. Our findings highlight the neurobiological role of RXR on sleep modulation.


Assuntos
Bexaroteno/farmacologia , Ácidos Cumáricos/farmacologia , Receptores X Retinoide/metabolismo , Fases do Sono/efeitos dos fármacos , Fases do Sono/fisiologia , Tetra-Hidronaftalenos/farmacologia , Animais , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores X Retinoide/agonistas , Receptores X Retinoide/antagonistas & inibidores
8.
Nature ; 581(7809): 475-479, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32461639

RESUMO

Intestinal health relies on the immunosuppressive activity of CD4+ regulatory T (Treg) cells1. Expression of the transcription factor Foxp3 defines this lineage, and can be induced extrathymically by dietary or commensal-derived antigens in a process assisted by a Foxp3 enhancer known as conserved non-coding sequence 1 (CNS1)2-4. Products of microbial fermentation including butyrate facilitate the generation of peripherally induced Treg (pTreg) cells5-7, indicating that metabolites shape the composition of the colonic immune cell population. In addition to dietary components, bacteria modify host-derived molecules, generating a number of biologically active substances. This is epitomized by the bacterial transformation of bile acids, which creates a complex pool of steroids8 with a range of physiological functions9. Here we screened the major species of deconjugated bile acids for their ability to potentiate the differentiation of pTreg cells. We found that the secondary bile acid 3ß-hydroxydeoxycholic acid (isoDCA) increased Foxp3 induction by acting on dendritic cells (DCs) to diminish their immunostimulatory properties. Ablating one receptor, the farnesoid X receptor, in DCs enhanced the generation of Treg cells and imposed a transcriptional profile similar to that induced by isoDCA, suggesting an interaction between this bile acid and nuclear receptor. To investigate isoDCA in vivo, we took a synthetic biology approach and designed minimal microbial consortia containing engineered Bacteroides strains. IsoDCA-producing consortia increased the number of colonic RORγt-expressing Treg cells in a CNS1-dependent manner, suggesting enhanced extrathymic differentiation.


Assuntos
Bactérias/metabolismo , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Sequência de Aminoácidos , Animais , Bacteroides/metabolismo , Colo/microbiologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Fermentação , Microbioma Gastrointestinal , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Consórcios Microbianos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
9.
Nat Commun ; 11(1): 1720, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249768

RESUMO

Nuclear localization of PTEN is essential for its tumor suppressive role, and loss of nuclear PTEN is more prominent than cytoplasmic PTEN in many kinds of cancers. However, nuclear PTEN-specific regulatory mechanisms were rarely reported. Based on the finding that nuclear PTEN is more unstable than cytoplasmic PTEN, here we identify that F-box only protein 22 (FBXO22) induces ubiquitylation of nuclear but not cytoplasmic PTEN at lysine 221, which is responsible for the degradation of nuclear PTEN. FBXO22 plays a tumor-promoting role by ubiquitylating and degrading nuclear PTEN. In accordance, FBXO22 is overexpressed in various cancer types, and contributes to nuclear PTEN downregulation in colorectal cancer tissues. Cumulatively, our study reports the mechanism to specifically regulate the stability of nuclear PTEN, which would provide the opportunity for developing therapeutic strategies aiming to achieve complete reactivation of PTEN as a tumor suppressor.


Assuntos
Carcinogênese/genética , Núcleo Celular/metabolismo , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/metabolismo , Proteínas F-Box/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Neoplasias Colorretais/genética , Citoplasma/metabolismo , Proteínas F-Box/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , PTEN Fosfo-Hidrolase/química , PTEN Fosfo-Hidrolase/genética , RNA Interferente Pequeno , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/genética , Espectrometria de Massas em Tandem , Análise Serial de Tecidos , Transplante Heterólogo , Ubiquitinação
10.
PLoS Genet ; 16(4): e1008687, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32282814

RESUMO

Environment shapes development through a phenomenon called developmental plasticity. Deciphering its genetic basis has potential to shed light on the origin of novel traits and adaptation to environmental change. However, molecular studies are scarce, and little is known about molecular mechanisms associated with plasticity. We investigated the gene regulatory network controlling predatory vs. non-predatory dimorphism in the nematode Pristionchus pacificus and found that it consists of genes of extremely different age classes. We isolated mutants in the conserved nuclear hormone receptor nhr-1 with previously unseen phenotypic effects. They disrupt mouth-form determination and result in animals combining features of both wild-type morphs. In contrast, mutants in another conserved nuclear hormone receptor nhr-40 display altered morph ratios, but no intermediate morphology. Despite divergent modes of control, NHR-1 and NHR-40 share transcriptional targets, which encode extracellular proteins that have no orthologs in Caenorhabditis elegans and result from lineage-specific expansions. An array of transcriptional reporters revealed co-expression of all tested targets in the same pharyngeal gland cell. Major morphological changes in this gland cell accompanied the evolution of teeth and predation, linking rapid gene turnover with morphological innovations. Thus, the origin of feeding plasticity involved novelty at the level of genes, cells and behavior.


Assuntos
Evolução Molecular , Proteínas de Helminto/genética , Comportamento Predatório , Receptores Citoplasmáticos e Nucleares/genética , Rabditídios/genética , Animais , Sequência Conservada , Redes Reguladoras de Genes , Proteínas de Helminto/metabolismo , Boca/anatomia & histologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Rabditídios/anatomia & histologia , Rabditídios/fisiologia , Análise de Célula Única
11.
PLoS One ; 15(4): e0232036, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343715

RESUMO

The NUP98 and NUP214 nucleoporins (NUPs) are recurrently fused to heterologous proteins in leukemia. The resulting chimeric oncoproteins retain the phenylalanine-glycine (FG) repeat motifs of the NUP moiety that mediate interaction with the nuclear export receptor Crm1. NUP fusion leukemias are characterized by HOXA gene upregulation; however, their molecular pathogenesis remains poorly understood. To investigate the role of Crm1 in mediating the leukemogenic properties of NUP chimeric proteins, we took advantage of the Sequestosome-1 (SQSTM1)-NUP214 fusion. SQSTM1-NUP214 retains only a short C-terminal portion of NUP214 which contains FG motifs that mediate interaction with Crm1. We introduced point mutations targeting these FG motifs and found that the ability of the resulting SQSTM1-NUP214FGmut protein to interact with Crm1 was reduced by more than 50% compared with SQSTM1-NUP214. Mutation of FG motifs affected transforming potential: while SQSTM1-NUP214 impaired myeloid maturation and conferred robust colony formation to transduced hematopoietic progenitors in a serial replating assay, the effect of SQSTM1-NUP214FGmut was considerably diminished. Moreover, SQSTM1-NUP214 caused myeloid leukemia in all transplanted mice, whereas none of the SQSTM1-NUP214FGmut reconstituted mice developed leukemia. These oncogenic effects coincided with the ability of SQSTM1-NUP214 and SQSTM1-NUP214FGmut to upregulate the expression of Hoxa and Meis1 genes in hematopoietic progenitors. Indeed, chromatin immunoprecipitation assays demonstrated that impaired SQSTM1-NUP214 interaction with Crm1 correlated with impaired binding of the fusion protein to Hoxa and Meis1 genes. These findings highlight the importance of Crm1 in mediating the leukemogenic properties of SQSTM1-NUP214, and suggest a conserved role of Crm1 in recruiting oncoproteins to their effector genes.


Assuntos
Proteínas de Homeodomínio/genética , Carioferinas/metabolismo , Leucemia/metabolismo , Proteína Meis1/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína Sequestossoma-1/genética , Motivos de Aminoácidos , Animais , Linhagem Celular , Regulação Neoplásica da Expressão Gênica , Leucemia/genética , Leucemia/patologia , Camundongos , Mutagênese Sítio-Dirigida , Transplante de Neoplasias , Complexo de Proteínas Formadoras de Poros Nucleares/química , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , Mutação Puntual , Regulação para Cima
12.
J Med Chem ; 63(8): 3881-3895, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32223194

RESUMO

Exportin-1 (also named as CRM1) plays a prominent role in autoimmune disorders and has emerged as a potential therapeutic target for colitis. Here we report on the rational structure-based discovery of a small-molecule antagonist of exportin-1, LFS-829, with low-range nanomolar activities. The co-crystallographic structure, surface plasmon resonance binding assay, and cell-based phenotypic nuclear export functional assay validated that exportin-1 is a key target of LFS-829. Moreover, we demonstrated that the C528S mutation or the knockdown on exportin-1 can abolish the cellular activities of LFS-829. Strikingly, oral administration of LFS-829 can significantly reverse the pathological features of colitis model mice. We revealed that LFS-829 can attenuate dual NF-κB signaling and the Nrf2 cytoprotection pathway via targeting exportin-1 in colitis mice. Moreover, LFS-829 has a very low risk of cardiotoxicity and acute toxicity. Therefore, LFS-829 holds great promise for the treatment of colitis and may warrant translation for use in clinical trials.


Assuntos
Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Hidrazinas/administração & dosagem , Carioferinas/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Triazóis/administração & dosagem , Sequência de Aminoácidos , Animais , Colite/metabolismo , Colite/patologia , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Hidrazinas/química , Carioferinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares/metabolismo , Triazóis/química
13.
Nat Rev Endocrinol ; 16(7): 363-377, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32303708

RESUMO

Nuclear receptor crosstalk can be defined as the interplay between different nuclear receptors or between their overlapping signalling pathways. A subset of nuclear receptors (such as PPARs and RARs) engage in the formation of well-characterized 'typical' heterodimers with RXR. 'Atypical' heterodimers (such as GR with PPARs, or PPAR with ERR) might form a novel class of physical complexes that might be more transient in nature. These heterodimers might harbour strong transcriptional flexibility, with no strict need for DNA binding of both partners. Direct crosstalk could stem from a pairwise physical association between atypical nuclear receptor heterodimers, either via pre-existing interaction pairs or via interactions that are newly induced with small molecules; such crosstalk might constitute an uncharted space to target nuclear receptor physiological and/or pathophysiological actions. In this Review, we discuss the emerging aspects of crosstalk in the nuclear receptor field and present various mechanistic crosstalk modes with examples that support applicability of the atypical heterodimer concept. Stabilization or disruption, in a context-dependent or cell type-dependent manner, of these more transient heterodimers is expected to fuel unprecedented translational approaches to yield novel therapeutic agents to treat major human diseases with higher precision.


Assuntos
Receptor Cross-Talk/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Terapias em Estudo/métodos , Animais , Humanos , Ligação Proteica/fisiologia , Multimerização Proteica/fisiologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/fisiologia , Terapias em Estudo/tendências , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia
14.
Artigo em Chinês | MEDLINE | ID: mdl-32148224

RESUMO

OBJECTIVE: To investigate the molecule mechanism of nuclear translocation of hypoxia-inducible factor-1α (HIF-1α) in influenza A (H1N1) virus infected-alveolar epithelial cells. METHODS: Human lung adenocarcinoma epithelial cells (A549 cells) were cultured in vitro, and cells in logarithmic growth phase were selected for experiments. (1) Experiment 1: the A549 cell model with H1N1 virus infection was established by using H1N1 virus infected cells with multiplicity of infection (MOI) 1.0 for 24 hours (H1N1 virus infection group), and the blank control group was set up. Importin 4 and Importin 7 protein expressions were detected by Western Blot to investigate whether HIF-1α nuclear translocation depended on Importin 4 or Importin 7. (2) Experiment 2: the A549 cells were infected with H1N1 virus under different MOI (0, 0.1, 0.5, 1.0, 2.0, 4.0) for 24 hours. Then the A549 cells were infected with H1N1 virus (MOI 1.0) for different time (0, 3, 6, 12, 18, 24, 36 hours). The septin 9 isoform 1 (SEPT9_i1) mRNA expression was detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR) to investigate the effect of different MOI and infection time on the expression of SEPT9_i1. (3) Experiment 3: a cell model with SEPT9_i1 silencing was established by transfection of small interfering RNA (siRNA) for 24 hours (siRNA-SEPT9_i1 group), and the blank control group and blank vector control group (siControl group) were set up. Then the cells in the three groups were infected with H1N1 virus (MOI 1.0) for 24 hours after 24-hour transfection, and the SEPT9_i1 mRNA expression was detected by real-time fluorescence quantitative RT-PCR to investigate the interference efficiency of siRNA-SEPT9_i1. (4) Experiment 4: the cells were divided into siControl group and siRNA-SEPT9_i1 group. The transfection methods of two groups was as the same as experiment 3,and then the cells were infected with H1N1 virus (MOI 1.0) after 24-hour transfection. The distribution of HIF-1α was detected by immunofluorescence at 24 hours after infection. The M gene expression of virus was detected by real-time fluorescence quantitative RT-PCR at 6, 12, 24, 36, 48 hours after infection. The effects of SEPT9_i1 on HIF-1α translocation and virus replication were explored. (5) Experiment 5: the cells were divided into blank control group (complete medium), SP600125 group [100 µmol/L c-Jun N-terminal kinase (JNK) signaling pathway inhibitor SP600125 for 2 hours], H1N1 virus infection group (H1N1 virus of MOI 1.0 for 24 hours), H1N1 virus+SP600125 group (pretreated with 100 µmol/L SP600125 for 2 hours before 24-hour H1N1 virus infection). Real-time fluorescence quantitative RT-PCR was used to detect the expressions of SEPT_i1 mRNA and viral M gene to investigate the effect of JNK signaling pathway on SEPT9_i1 expression and virus replication. RESULTS: (1) Experiment 1: compared with the blank control group, the protein expressions of Importin 4 and Importin 7 in the H1N1 virus infection group had no significant changes [Importin 4 protein (Importin 4/GAPDH): 1.08±0.03 vs. 1.05±0.03, Importin 7 protein (Importin 7/GAPDH): 0.87±0.11 vs. 0.78±0.03, both P > 0.05]. These indicated that the HIF-1α nuclear translocation in A549 cells might not be independent of Importin 4 and Importin 7 during H1N1 virus infection. (2) Experiment 2: the SEPT9_i1 mRNA expression in A549 cells was increased with the increase in MOI and infection time of H1N1 virus, and peaked at MOI 2.0 or 18 hours after infection, and the differences were statistically significant as compared with MOI 0 or 0 hour after infection (2-ΔΔCT: 1.39±0.05 vs. 1.00±0.00 at MOI 2.0, 1.47±0.04 vs. 1.00±0.00 at 18 hours, both P < 0.01). This indicated that the SEPT9_i1 expression in A549 cells was related to the MOI and the infection time during H1N1 virus infection. (3) Experiment 3: compared with the blank control group, the SEPT9_i1 mRNA expression in A549 cells was significantly decreased in the siRNA-SEPT9_i1 group (2-ΔΔCT: 0.38±0.11 vs. 1.00±0.00, P < 0.01), and there was no significant difference between the siControl group and blank control group (2-ΔΔCT: 1.03±0.16 vs. 1.00±0.00, P > 0.05). This indicated that SEPT9_i1 silence could inhibit the expression of SEPT9_i1 mRNA in H1N1 virus-infected A549 cells. (4) Experiment 4: HIF-1α nuclear translocation in the H1N1 virus-infected A549 cells in the siRNA-SEPT9_i1 group was significantly reduced as compared with the siControl group. The virus M gene expression after H1N1 virus infection in the siControl group was gradually increased, and peaked at 48 hours. The expression of virus M gene in A549 cells in the siRNA-SEPT9_i1 group was significantly down-regulated, and showed a statistically significant difference at 48 hours as compared with the siControl group (2-ΔΔCT: 3.47±0.66 vs. 8.17±0.38, P < 0.05). This indicated that HIF-1α nuclear translocation and virus replication in H1N1 virus-infected A549 cells were inhibited after silencing SEPT9_i1. (5) Experiment 5: the expressions of SEPT9_i1 mRNA and virus M gene in A549 cells in the H1N1 virus infection group were significantly higher than those in the blank control group. However, the expressions of SEPT9_i1 mRNA and viral M gene in A549 cells in the H1N1 virus+SP600125 group were significantly lower than those in the H1N1 virus infection group (2-ΔΔCT: SEPT9_i1 mRNA was 0.12±0.10 vs. 1.53±0.14, viral M gene was 2.13±0.10 vs. 4.66±0.14, both P < 0.05). There was no significant difference in above indicators between the SP600125 group and the blank control group. This indicated that the JNK signaling pathway could regulate the expression of SEPT9_i1 in A549 cells during H1N1 virus infection, and the JNK signaling pathway inhibition could down-regulate the expression of SEPT9_i1 and inhibit virus replication. CONCLUSIONS: The H1N1 virus regulates the expression of SEPT9_i1 by activating the JNK signaling pathway, thus increase HIF-1α transport efficiency and H1N1 replication.


Assuntos
Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Vírus da Influenza A Subtipo H1N1 , Células A549 , Transporte Ativo do Núcleo Celular , Humanos , Influenza Humana , Carioferinas/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana Transportadoras/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Septinas/metabolismo
15.
Chem Biol Interact ; 324: 109062, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32198087

RESUMO

Ginsenoside Rg1 is an active ingredient extracted from the roots of ginsenoside, and an α-naphthylisothiocyanate (ANIT)-induced rat model of intrahepatic cholestasis was used to investigate the protective effect of Rg1 on cholestasis. 48 SD male rats were randomly divided into 6 groups: control group, model group, UDCA group (ursodeoxycholic acid), low-dose Rg1 group (10 mg/kg), medium-dose Rg1 group (20 mg/kg) and high-dose Rg1 group (40 mg/kg). The model group, the UDCA group and all the Rg1 group were then intragastrically administered with 80 mg/kg ANIT, and the control group were given equal volume of olive oil. Then the pathological changes in liver tissue were observed, the secretion of bile in the bile duct was measured, and the biochemical markers in serum were quantified, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), glutamyl transfer peptidase (GTP) and the content of total bilirubin (TBIL), direct bilirubin (DBIL), total bile acid (TBA). The contents of inflammatory mediators in serum were quantified, including tumor necrosis factor (TNF-α), γ-interferon (IFN-γ) and interleukin-1ß (IL-1ß). The contents of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in liver homogenate were quantified. Expression of farnesoid X receptor (FXR), transporters and metabolic enzymes in liver tissue was monitored. Rg1 treatment improved liver tissue pathological damage, promoted bile secretion and significantly reduced serum levels of the intrahepatic cholestasis markers ALT, AST, ALP, GTP, TBIL, DBIL and TBA. Rg1 increased the activity of SOD and GSH-Px in liver homogenate, while, reducing the serum levels of MDA and inflammatory mediators. Rg1 also regulated the expression of FXR, bile acid transporters and metabolic enzymes. Overall, Rg1 alleviated liver injury by improving secretion of bile and normalizing the activity of enzymes in the serum. The protective mechanism appeared to be related to the activation of FXR and regulation of liver transporters and metabolic enzymes.


Assuntos
Colestase Intra-Hepática/tratamento farmacológico , Ginsenosídeos/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Substâncias Protetoras/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , 1-Naftilisotiocianato , Animais , Bile/metabolismo , Biomarcadores/metabolismo , Colestase Intra-Hepática/induzido quimicamente , Colestase Intra-Hepática/patologia , Citocromo P-450 CYP3A/metabolismo , Citocinas/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa Peroxidase/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Ratos Sprague-Dawley , Sulfotransferases/metabolismo , Superóxido Dismutase/metabolismo
16.
Mol Pharmacol ; 97(5): 314-323, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32098797

RESUMO

Farnesoid X receptor (FXR), or NR1H4, protects the liver from insults of various etiologies. A role of FXR in drug-induced liver injury has also been hypothesized yet only marginally investigated. The aim of this study was to assess the effect of FXR activation on gene expression and phenotype of the liver of mice treated with valproic acid (VPA), or 2-propylpentanoic acid, a prototypical hepatotoxic drug. Obeticholic acid (OCA) was used to activate FXR both in mice and in human hepatocellular carcinoma (Huh-7) cells. Next-generation sequencing of mouse liver tissues was performed from control, VPA, and VPA + OCA-treated mice. Pathway analysis validation was performed using real-time reverse-transcription polymerase chain reaction, Western blotting, immunohistochemistry, and fluorometric assays. FXR activation induced antioxidative pathways, which was confirmed by a marked reduction in VPA-induced lipid peroxidation and endoplasmic reticulum stress. In vitro, VPA-induced oxidative stress was independent of lipid accumulation, stemmed from the cytoplasm, and was mitigated by OCA. In the liver of the mice treated with OCA, the levels of cytochrome P450 potentially involved in VPA metabolism were increased. The hepatic lipid-lowering effect observed in animals cotreated with VPA and OCA in comparison with that of animals treated with VPA was associated with regulation of the genes involved in the steatogenic nuclear receptor peroxisome proliferator-activated γ (PPARγ) pathway. In conclusion, pronounced antioxidant activity, repression of the PPARγ pathway, and higher expression of P450 enzymes involved in VPA metabolism may underlie the hepatoprotective of FXR activation during VPA treatment. SIGNIFICANCE STATEMENT: Valproic acid-induced oxidative stress occurs in absence of lipid accumulation and is not of mitochondrial origin. Valproic acid exposure induces the expression of the steatogenic nuclear receptor peroxisome proliferator-activated γ (PPARγ) and its downstream target genes. Constitutive activation of the farnesoid X receptor (FXR) reduces PPARγ hepatic expression and induces hepatic antioxidant activity. The variability in FXR expression level/activity, for instance in individuals carrying loss-of-function genetic variants of the FXR gene, could contribute to valproic acid pharmacokinetic and toxicokinetic profile.


Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Estresse Oxidativo , Ácido Valproico/efeitos adversos , Animais , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico , Sistema Enzimático do Citocromo P-450/metabolismo , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/fisiopatologia , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Testes de Função Hepática , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transcriptoma/genética
17.
PLoS One ; 15(2): e0224644, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32101552

RESUMO

Polybrominated diphenyl ethers (PBDEs) were formally used as flame-retardants and are chemically stable, lipophlic persistent organic pollutants which are known to bioaccumulate in humans. Although its toxicities are well characterized, little is known about the changes in transcriptional regulation caused by PBDE exposure. Long non-coding RNAs (lncRNAs) are increasingly recognized as key regulators of transcriptional and translational processes. It is hypothesized that lncRNAs can regulate nearby protein-coding genes (PCGs) and changes in the transcription of lncRNAs may act in cis to perturb gene expression of its neighboring PCGs. The goals of this study were to 1) characterize PCGs and lncRNAs that are differentially regulated from exposure to PBDEs; 2) identify PCG-lncRNA pairs through genome annotation and predictive binding tools; and 3) determine enriched canonical pathways caused by differentially expressed lncRNA-PCGs pairs. HepaRG cells, which are human-derived hepatic cells that accurately represent gene expression profiles of human liver tissue, were exposed to BDE-47 and BDE-99 at a dose of 25 µM for 24 hours. Differentially expressed lncRNA-PCG pairs were identified through DESeq2 and HOMER; significant canonical pathways were determined through Ingenuity Pathway Analysis (IPA). LncTar was used to predict the binding of 19 lncRNA-PCG pairs with known roles in drug-processing pathways. Genome annotation revealed that the majority of the differentially expressed lncRNAs map to PCG introns. PBDEs regulated overlapping pathways with PXR and CAR such as protein ubiqutination pathway and peroxisome proliferator-activated receptor alpha-retinoid X receptor alpha (PPARα-RXRα) activation but also regulate distinctive pathways involved in intermediary metabolism. PBDEs uniquely down-regulated GDP-L-fucose biosynthesis, suggesting its role in modifying important pathways involved in intermediary metabolism such as carbohydrate and lipid metabolism. In conclusion, we provide strong evidence that PBDEs regulate both PCGs and lncRNAs in a PXR/CAR ligand-dependent and independent manner.


Assuntos
Retardadores de Chama/farmacologia , Perfilação da Expressão Gênica/métodos , Éteres Difenil Halogenados/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , RNA Longo não Codificante/metabolismo , Metabolismo dos Carboidratos , Linhagem Celular , Retardadores de Chama/administração & dosagem , Regulação da Expressão Gênica , Éteres Difenil Halogenados/administração & dosagem , Humanos , Íntrons/genética , Metabolismo dos Lipídeos , PPAR alfa/metabolismo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptor X Retinoide alfa/metabolismo
18.
Nature ; 579(7797): 123-129, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103176

RESUMO

A mosaic of cross-phylum chemical interactions occurs between all metazoans and their microbiomes. A number of molecular families that are known to be produced by the microbiome have a marked effect on the balance between health and disease1-9. Considering the diversity of the human microbiome (which numbers over 40,000 operational taxonomic units10), the effect of the microbiome on the chemistry of an entire animal remains underexplored. Here we use mass spectrometry informatics and data visualization approaches11-13 to provide an assessment of the effects of the microbiome on the chemistry of an entire mammal by comparing metabolomics data from germ-free and specific-pathogen-free mice. We found that the microbiota affects the chemistry of all organs. This included the amino acid conjugations of host bile acids that were used to produce phenylalanocholic acid, tyrosocholic acid and leucocholic acid, which have not previously been characterized despite extensive research on bile-acid chemistry14. These bile-acid conjugates were also found in humans, and were enriched in patients with inflammatory bowel disease or cystic fibrosis. These compounds agonized the farnesoid X receptor in vitro, and mice gavaged with the compounds showed reduced expression of bile-acid synthesis genes in vivo. Further studies are required to confirm whether these compounds have a physiological role in the host, and whether they contribute to gut diseases that are associated with microbiome dysbiosis.


Assuntos
Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/química , Metabolômica , Microbiota/fisiologia , Animais , Ácidos e Sais Biliares/metabolismo , Ácido Cólico/biossíntese , Ácido Cólico/química , Ácido Cólico/metabolismo , Fibrose Cística/genética , Fibrose Cística/metabolismo , Fibrose Cística/microbiologia , Vida Livre de Germes , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/microbiologia , Camundongos , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
19.
Am J Physiol Gastrointest Liver Physiol ; 318(3): G582-G609, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32003601

RESUMO

To investigate the role of bile acids (BAs) in the pathogenesis of diet-induced nonalcoholic steatohepatitis (NASH), we fed a "Western-style diet" [high fructose, high fat (HFF)] enriched with fructose, cholesterol, and saturated fat for 10 wk to juvenile Iberian pigs. We also supplemented probiotics with in vitro BA deconjugating activity to evaluate their potential therapeutic effect in NASH. Liver lipid and function, cytokines, and hormones were analyzed using commercially available kits. Metabolites, BAs, and fatty acids were measured by liquid chromatography-mass spectrometry. Histology and gene and protein expression analyses were performed using standard protocols. HFF-fed pigs developed NASH, cholestasis, and impaired enterohepatic Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling in the absence of obesity and insulin resistance. Choline depletion in HFF livers was associated with decreased lipoprotein and cholesterol in serum and an increase of choline-containing phospholipids in colon contents and trimethylamine-N-oxide in the liver. Additionally, gut dysbiosis and hyperplasia increased with the severity of NASH, and were correlated with increased colonic levels of choline metabolites and secondary BAs. Supplementation of probiotics in the HFF diet enhanced NASH, inhibited hepatic autophagy, increased excretion of taurine and choline, and decreased gut microbial diversity. In conclusion, dysregulation of BA homeostasis was associated with injury and choline depletion in the liver, as well as increased biliary secretion, gut metabolism and excretion of choline-based phospholipids. Choline depletion limited lipoprotein synthesis, resulting in hepatic steatosis, whereas secondary BAs and choline-containing phospholipids in colon may have promoted dysbiosis, hyperplasia, and trimethylamine synthesis, causing further damage to the liver.NEW & NOTEWORTHY Impaired Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling and cholestasis has been described in nonalcoholic fatty liver disease (NAFLD) patients. However, therapeutic interventions with FXR agonists have produced contradictory results. In a swine model of pediatric nonalcoholic steatohepatitis (NASH), we show that the uncoupling of intestinal FXR-FGF19 signaling and a decrease in FGF19 levels are associated with a choline-deficient phenotype of NASH and increased choline excretion in the gut, with the subsequent dysbiosis, colonic hyperplasia, and accumulation of trimethylamine-N-oxide in the liver.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colina/metabolismo , Colo/metabolismo , Colo/microbiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Microbioma Gastrointestinal , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores Etários , Animais , Colo/patologia , Modelos Animais de Doenças , Disbiose , Feminino , Hiperplasia , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Probióticos/administração & dosagem , Transdução de Sinais , Sus scrofa
20.
Biochem Biophys Res Commun ; 524(3): 614-620, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32029270

RESUMO

Deformation of vacuolar membranes mediated by endosomal sorting complex required for transport (ESCRT) is necessary for microautophagy. Target of rapamycin complex 1 (TORC1) protein kinase negatively regulates ESCRT-0 (Vps27-Hse1) recruitment onto vacuolar membranes and microautophagy induction. However, whether and how protein phosphatase regulates these events is unknown. Here, we show that the TORC1-downstream protein phosphatase PP2A-Cdc55 is important for these events after TORC1 inactivation in budding yeast. Loss of PP2A-Cdc55 compromised vacuolar localization of Hse1, but not Vps27. This study revealed that the orchestrated action of PP2A induces microautophagy upon TORC1 inactivation.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Membranas Intracelulares/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Microautofagia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ligação Proteica , Proteína Fosfatase 2/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
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