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Pesquisa : D12.776.157.530.450.625.202 [Categoria DeCS]
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  1 / 569 MEDLINE  
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[PMID]:28391691
[Au] Autor:Feng M; Betti M
[Ad] Endereço:Department of Agricultural, Food and Nutritional Science, University of Alberta , 410 Agriculture/Forestry Centre, Edmonton, AB T6G 2P5, Canada.
[Ti] Título:Both PepT1 and GLUT Intestinal Transporters Are Utilized by a Novel Glycopeptide Pro-Hyp-CONH-GlcN.
[So] Source:J Agric Food Chem;65(16):3295-3304, 2017 Apr 26.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pro-Hyp (PO) accounts for many beneficial biological effects of collagen hydrolysates for skin and bone health. The objective of this study was to conjugate PO with glucosamine (GlcN) to create a novel glycopeptide Pro-Hyp-CONH-GlcN (POGlcN) and then to investigate the potential involvement of multiple transepithelial transport pathways for this glycopeptide. Nuclear magnetic resonance results revealed the amide nature of this glycopeptide with α and ß configurations derived from GlcN. This glycopeptide was very resistant to simulated gastrointestinal digestion. Also, it showed a rate of transepithelial transport [permeability coefficient (P ) of (2.82 ± 0.15) × 10 cm/s] across the Caco-2 cell monolayer superior to those of parental dipeptide PO and GlcN [P values of (1.45 ± 0.17) × 10 and (1.87 ± 0.15) × 10 cm/s, respectively]. A transport mechanism experiment indicated that the improved transport efficiency of POGlcN is attributed to the introduction of glucose transporters.
[Mh] Termos MeSH primário: Transportador de Glucose Tipo 2/metabolismo
Glicopeptídeos/metabolismo
Simportadores/metabolismo
[Mh] Termos MeSH secundário: Transporte Biológico
Células CACO-2
Glucose/metabolismo
Transportador de Glucose Tipo 2/química
Glicopeptídeos/química
Seres Humanos
Intestinos
Transportador 1 de Peptídeos
Simportadores/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glucose Transporter Type 2); 0 (Glycopeptides); 0 (Peptide Transporter 1); 0 (SLC15A1 protein, human); 0 (SLC2A2 protein, human); 0 (Symporters); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170411
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b00815


  2 / 569 MEDLINE  
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[PMID]:28336547
[Au] Autor:Stelzl T; Geillinger-Kästle KE; Stolz J; Daniel H
[Ad] Endereço:Nutritional Physiology, Technische Universität München, Freising, Germany.
[Ti] Título:Glycans in the intestinal peptide transporter PEPT1 contribute to function and protect from proteolysis.
[So] Source:Am J Physiol Gastrointest Liver Physiol;312(6):G580-G591, 2017 Jun 01.
[Is] ISSN:1522-1547
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Despite the fact that many membrane proteins carry extracellular glycans, little is known about whether the glycan chains also affect protein function. We recently demonstrated that the proton-coupled oligopeptide transporter 1 (PEPT1) in the intestine is glycosylated at six asparagine residues (N50, N406, N439, N510, N515, and N532). Mutagenesis-induced disruption of the individual -glycosylation site N50, which is highly conserved among mammals, was detected to significantly enhance the PEPT1-mediated inward transport of peptides. Here, we show that for the murine protein the inhibition of glycosylation at sequon N50 by substituting N50 with glutamine, lysine, or cysteine or by replacing S52 with alanine equally altered PEPT1 transport kinetics in oocytes. Furthermore, we provide evidence that the uptake of [ C]glycyl-sarcosine in immortalized murine small intestinal (MODE-K) or colonic epithelial (PTK-6) cells stably expressing the PEPT1 transporter N50Q is also significantly increased relative to the wild-type protein. By using electrophysiological recordings and tracer flux studies, we further demonstrate that the rise in transport velocity observed for PEPT1 N50Q is bidirectional. In line with these findings, we show that attachment of biotin derivatives, comparable in weight with two to four monosaccharides, to the PEPT1 N50C transporter slows down the transport velocity. In addition, our experiments provide strong evidence that glycosylation of PEPT1 confers resistance against proteolytic cleavage by proteinase K, whereas a remarkable intrinsic stability against trypsin, even in the absence of -linked glycans, was detected. This study highlights the role of N50-linked glycans in modulating the bidirectional transport activity of the murine peptide transporter PEPT1. Electrophysiological and tracer flux measurements in oocytes have shown that removal of the N50 glycans increases the maximal peptide transport rate in the inward and outward directions. This effect could be largely reversed by replacement of N50 glycans with structurally dissimilar biotin derivatives. In addition, -glycans were detected to stabilize PEPT1 against proteolytic cleavage.
[Mh] Termos MeSH primário: Dipeptídeos/metabolismo
Endopeptidase K/metabolismo
Células Epiteliais/metabolismo
Mucosa Intestinal/metabolismo
Processamento de Proteína Pós-Traducional
Proteólise
Simportadores/metabolismo
[Mh] Termos MeSH secundário: Animais
Transporte Biológico
Biotinilação
Linhagem Celular
Glicosilação
Cinética
Potenciais da Membrana
Camundongos
Mutação
Transportador 1 de Peptídeos
Estabilidade Proteica
Simportadores/genética
Transfecção
Tripsina/metabolismo
Xenopus laevis
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Dipeptides); 0 (Peptide Transporter 1); 0 (Slc15a1 protein, mouse); 0 (Symporters); 29816-01-1 (glycylsarcosine); EC 3.4.21.4 (Trypsin); EC 3.4.21.64 (Endopeptidase K)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170325
[St] Status:MEDLINE
[do] DOI:10.1152/ajpgi.00343.2016


  3 / 569 MEDLINE  
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[PMID]:28099762
[Au] Autor:Huo X; Wang C; Yu Z; Peng Y; Wang S; Feng S; Zhang S; Tian X; Sun C; Liu K; Deng S; Ma X
[Ad] Endereço:Key Laboratory of Pharmacokinetic and Drug Transport of Liaoning, College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China.
[Ti] Título:Human transporters, PEPT1/2, facilitate melatonin transportation into mitochondria of cancer cells: An implication of the therapeutic potential.
[So] Source:J Pineal Res;62(4), 2017 May.
[Is] ISSN:1600-079X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Melatonin is present in virtually all organisms from bacteria to mammals, and it exhibits a broad spectrum of biological functions, including synchronization of circadian rhythms and oncostatic activity. Several functions of melatonin are mediated by its membrane receptors, but others are receptor-independent. For the latter, melatonin is required to penetrate membrane and enters intracellular compartments. However, the mechanism by which melatonin enters cells remains debatable. In this study, it was identified that melatonin and its sulfation metabolites were the substrates of oligopeptide transporter (PEPT) 1/2 and organic anion transporter (OAT) 3, respectively. The docking analysis showed that the binding of melatonin to PEPT1/2 was attributed to their low binding energy and suitable binding conformation in which melatonin was embedded in the active site of PEPT1/2 and fitted well with the cavity in three-dimensional space. PEPT1/2 transporters play a pivotal role in melatonin uptake in cells. Melatonin's membrane transportation via PEPT1/2 renders its oncostatic effect in malignant cells. For the first time, PEPT1/2 were identified to localize in the mitochondrial membrane of human cancer cell lines of PC3 and U118. PEPT1/2 facilitated the transportation of melatonin into mitochondria. Melatonin accumulation in mitochondria induced apoptosis of PC3 and U118 cells. Thus, PEPT1/2 can potentially be used as a cancer cell-targeted melatonin delivery system to improve the therapeutic effects of melatonin in cancer treatment.
[Mh] Termos MeSH primário: Melatonina/metabolismo
Mitocôndrias/metabolismo
Simportadores/metabolismo
[Mh] Termos MeSH secundário: Western Blotting
Células CACO-2
Linhagem Celular
Cromatografia Líquida
Citometria de Fluxo
Células HeLa
Seres Humanos
Potencial da Membrana Mitocondrial/genética
Potencial da Membrana Mitocondrial/fisiologia
Transportador 1 de Peptídeos
Espécies Reativas de Oxigênio/metabolismo
Simportadores/genética
Espectrometria de Massas em Tandem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Peptide Transporter 1); 0 (Reactive Oxygen Species); 0 (Symporters); 0 (hydrogen-coupled oligopeptide transporter PepT2); JL5DK93RCL (Melatonin)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170119
[St] Status:MEDLINE
[do] DOI:10.1111/jpi.12390


  4 / 569 MEDLINE  
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[PMID]:28044454
[Au] Autor:Lo Cascio P; Calabrò C; Bertuccio C; Paterniti I; Palombieri D; Calò M; Albergamo A; Salvo A; Gabriella Denaro M
[Ad] Endereço:a Department of Chemical, Biological, Pharmacological and Environmental Sciences , University of Messina , Messina , Italy.
[Ti] Título:Effects of fasting and refeeding on the digestive tract of zebrafish (Danio rerio) fed with Spirulina (Arthrospira platensis), a high protein feed source.
[So] Source:Nat Prod Res;31(13):1478-1485, 2017 Jul.
[Is] ISSN:1478-6427
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In the present work, morphological and molecular effects of short-term feed deprivation and refeeding with Spirulina (Arthrospira platensis) on zebrafish digestive tract were determined. Once elucidated the proximate composition of Spirulina feed, immunohistochemical and western blot analyses of peptide transporter (PepT1) and cholecystokinin (CCK8) were carried out in the gastrointestinal tract of zebrafish, previously morphologically investigated. Two and five fasting days caused not only morphostructural alterations, but also the downregulation of PepT1 and CCK8 proteins. Conversely, the recovery of normal morphological conditions, along with an increased PepT1 and CCK8 expression, were observed after refeeding with Spirulina. The increase of PepT1 expression in zebrafish may be responsible for the enhanced CCK8 secretion, so that both proteins may contribute to an improved digestion process during refeeding. These observations could be supported not only by compensatory mechanisms induced by fasting and refeeding but also by an higher protein quality of Spirulina-based diet.
[Mh] Termos MeSH primário: Jejum
Trato Gastrointestinal/efeitos dos fármacos
Spirulina/metabolismo
Peixe-Zebra/fisiologia
[Mh] Termos MeSH secundário: Ração Animal
Animais
Dieta
Transportador 1 de Peptídeos
Proteínas/farmacologia
Sincalida/metabolismo
Simportadores/metabolismo
Proteínas de Peixe-Zebra
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Peptide Transporter 1); 0 (Proteins); 0 (Symporters); 0 (Zebrafish Proteins); 0 (slc15a1 protein, zebrafish); M03GIQ7Z6P (Sincalide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170104
[St] Status:MEDLINE
[do] DOI:10.1080/14786419.2016.1274893


  5 / 569 MEDLINE  
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[PMID]:28038428
[Au] Autor:Liu J; Shi B; Shi K; Ma G; Zhang H; Lou X; Liu H; Wan S; Liang D
[Ad] Endereço:Intensive Care Unit, Zhejiang Provincial People's Hospital, NO. 158, Shangtang Road, Hangzhou 310014, China. Electronic address: liujqaticu@163.com.
[Ti] Título:Ghrelin upregulates PepT1 activity in the small intestine epithelium of rats with sepsis.
[So] Source:Biomed Pharmacother;86:669-676, 2017 Feb.
[Is] ISSN:1950-6007
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Sepsis causes nutritional substrate malabsorption; hence, preventing gut barrier problems and improving the nutritional status in sepsis is a compelling issue. AIMS: We tested whether ghrelin administration affects peptide transporter 1 (PepT1) activity in the intestinal epithelium of rats with sepsis. METHODS: Sixty male Sprague-Dawley rats were randomly divided into sham-operated, sepsis, and ghrelin-treated groups. The cecum of sham-operated rats was separated after laparotomy without ligation and perforation. Sepsis group rats underwent cecal ligation and puncture (CLP). Mucosal specimens were used for immunohistochemstry, real-time PCR, and western blotting to detect PepT1 distribution, and mRNA and protein expression levels, respectively. TNF-α, IL-1ß, and ghrelin levels were estimated in serum and intestinal mucosal tissue by ELISA. High-performance liquid chromatography was used to measure PepT1 uptake by the epithelial cells. Moreover, survival, body weight, and food intake of the rats were recorded during the 7-day treatment period. RESULTS: All rats in the sham-operated group survived, and 80% of rats in the sepsis group died within 7d of CLP. Treatment with ghrelin attenuated the CLP-induced body weight loss, intestine mucosa damage, and the survival rate was better. In addition, ghrelin attenuated increases in TNF-α and IL-1ß production. The expressions of PepT1 mRNA and protein were higher in ghrelin-treated group rats than in sepsis rats. Moreover, the uptake function of PepT1 was better in ghrelin-treated group rats. CONCLUSION: Ghrelin treatment can reduce the inflammatory response and greatly upregulate the physiological function of PepT1 in intestinal epithelial cells of rats with sepsis.
[Mh] Termos MeSH primário: Grelina/metabolismo
Mucosa Intestinal/metabolismo
Intestino Delgado/metabolismo
Sepse/metabolismo
Simportadores/metabolismo
Regulação para Cima/fisiologia
[Mh] Termos MeSH secundário: Animais
Modelos Animais de Doenças
Interleucina-1beta/metabolismo
Ligadura/métodos
Masculino
Transportador 1 de Peptídeos
RNA Mensageiro/metabolismo
Ratos
Ratos Sprague-Dawley
Fator de Necrose Tumoral alfa/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ghrelin); 0 (Interleukin-1beta); 0 (Peptide Transporter 1); 0 (RNA, Messenger); 0 (Slc15a1 protein, rat); 0 (Symporters); 0 (Tumor Necrosis Factor-alpha)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161231
[St] Status:MEDLINE


  6 / 569 MEDLINE  
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[PMID]:27916534
[Au] Autor:Kitamura K; Kinsui EZ; Abe F
[Ad] Endereço:Center for Gene Science, Hiroshima University, 1-4-2 Kagamiyama, Higashi-Hiroshima 739-8527, Japan. Electronic address: kkita@hiroshima-u.ac.jp.
[Ti] Título:Critical role of the proton-dependent oligopeptide transporter (POT) in the cellular uptake of the peptidyl nucleoside antibiotic, blasticidin S.
[So] Source:Biochim Biophys Acta;1864(2):393-398, 2017 02.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Blasticidin S (BlaS) interferes in the cell growth of both eukaryotes and prokaryotes. Its mode of action as a protein synthesis inhibitor has been investigated extensively. However, the mechanism of BlaS transport into the target cells is not understood well. Here, we show that Ptr2, a member of the proton-dependent oligopeptide transporter (POT) family, is responsible for the uptake of BlaS in yeasts Schizosaccharomyces pombe and Saccharomyces cerevisiae. Notably, some mutants of Ptr2 that are dysfunctional in dipeptide uptake were still competent to transport BlaS. Mouse-derived oligopeptide transporter PepT1 conferred BlaS sensitivity in the S. cerevisiae ptr2∆ mutant. Furthermore, bacterial POT family proteins also potentiated the BlaS sensitivity of E. coli. The role of the POT family oligopeptide transporters in the uptake of BlaS is conserved across species from bacteria to mammals.
[Mh] Termos MeSH primário: Antibacterianos/metabolismo
Proteínas de Membrana Transportadoras/fisiologia
Proteínas de Saccharomyces cerevisiae/fisiologia
[Mh] Termos MeSH secundário: Animais
Camundongos
Nucleosídeos/metabolismo
Transportador 1 de Peptídeos
Saccharomyces cerevisiae/metabolismo
Simportadores/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Membrane Transport Proteins); 0 (Nucleosides); 0 (PTR2 protein, S cerevisiae); 0 (Peptide Transporter 1); 0 (Saccharomyces cerevisiae Proteins); 0 (Slc15a1 protein, mouse); 0 (Symporters); 83U64J9U23 (blasticidin S)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161206
[St] Status:MEDLINE


  7 / 569 MEDLINE  
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[PMID]:27719884
[Au] Autor:Wang B; Li B
[Ad] Endereço:Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
[Ti] Título:Effect of molecular weight on the transepithelial transport and peptidase degradation of casein-derived peptides by using Caco-2 cell model.
[So] Source:Food Chem;218:1-8, 2017 Mar 01.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The transepithelial transport routes of casein-derived peptides with different molecular weights (MWs) were investigated using a Caco-2 cell monolayer. The peptidase hydrolysis during transport was also studied. The results indicate that the paracellular route was the main pathway for F1 (1600-1300Da) and F2 (1000-500Da), and the bioavailabilities were 10.66% and 9.54%, respectively. Peptidase hydrolysis results reveal that brush-border peptidases (BBPs) as well as some other peptidases were responsible for peptide degradation in the paracellular route. The maximum hydrolysis rate of the former was 6.91 and 5.59µM Gly/min for the latter. However, PepT1 was involved in the transport of F3 (<500Da) and its bioavailability was 16.23%. BBPs were the main peptidases involved in the PepT1 transport and the maximum hydrolysis rate was 11.4µM Gly/min. Furthermore, we found that the amino acid sequence of di- and tripeptides might affect their bioavailabilities significantly.
[Mh] Termos MeSH primário: Caseínas/farmacocinética
Peptídeo Hidrolases/metabolismo
Peptídeos/farmacocinética
[Mh] Termos MeSH secundário: Disponibilidade Biológica
Transporte Biológico
Células CACO-2
Seres Humanos
Hidrólise
Microvilosidades/metabolismo
Peso Molecular
Transportador 1 de Peptídeos
Simportadores/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Caseins); 0 (Peptide Transporter 1); 0 (Peptides); 0 (SLC15A1 protein, human); 0 (Symporters); EC 3.4.- (Peptide Hydrolases)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161011
[St] Status:MEDLINE


  8 / 569 MEDLINE  
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[PMID]:27693627
[Au] Autor:Orozco ZG; Soma S; Kaneko T; Watanabe S
[Ad] Endereço:Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo, Tokyo 113-8657, Japan.
[Ti] Título:Effects of fasting and refeeding on gene expression of slc15a1a, a gene encoding an oligopeptide transporter (PepT1), in the intestine of Mozambique tilapia.
[So] Source:Comp Biochem Physiol B Biochem Mol Biol;203:76-83, 2017 Jan.
[Is] ISSN:1879-1107
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The tissue distribution of slc15a1a, a gene that encodes an oligopeptide transporter, PepT1, and its response to fasting and refeeding were investigated in the intestinal epithelium of Mozambique tilapia for a better understanding of its role on nutrient absorption. The slc15a1a was predominantly expressed in the absorptive epithelia of the anterior part of the intestine, suggesting that digested oligopeptides are primarily absorbed in the anterior intestine. The response of slc15a1a to fasting was evaluated at 1, 2, 4, 7 and 14days after the last feeding. Fasting revealed a biphasic effect, where short-term fasting significantly upregulated slc15a1a expression and long-term fasting resulted in downregulation. The expression level continued to decrease and fell below the pre-fasted level from day 4 to 14. Proximal (the hepatic loop, HL) and distal parts (the proximal major coil, PMC) of the anterior intestine showed different magnitudes of responses to fasting; slc15a1a expression in the PMC showed greater upregulation and downregulation than that in the HL. Refeeding significantly stimulated slc15a1a expression at day 3, although the expression did not exceed the pre-fasted level. Observed responses of slc15a1a to fasting and refeeding suggest that the expression level of this gene can serve as a sensitive indicator of the changes that may occur in altering nutritional conditions. These findings contribute to a better understanding of the role of PepT1 in nutrition and of the complex mechanisms underlying the absorption of oligopeptides and amino acids in the intestine, and may lead to development of possible means to manipulate the absorption processes for the improvement of growth and other metabolic and physiological conditions in fish.
[Mh] Termos MeSH primário: Ingestão de Alimentos
Jejum/metabolismo
Proteínas de Peixes/genética
Regulação da Expressão Gênica
Intestinos/metabolismo
Simportadores/genética
Tilápia/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Clonagem Molecular
Proteínas de Peixes/química
Proteínas de Peixes/metabolismo
Transportador 1 de Peptídeos
Transporte Proteico
Simportadores/química
Simportadores/metabolismo
Tilápia/metabolismo
Tilápia/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fish Proteins); 0 (Peptide Transporter 1); 0 (Symporters)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161106
[St] Status:MEDLINE


  9 / 569 MEDLINE  
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[PMID]:27941311
[Au] Autor:Abousaab A; Warsi J; Salker MS; Lang F
[Ad] Endereço:Department of Cardiology, Vascular Medicine and Physiology, University of Tuebingen, Tuebingen, Germany.
[Ti] Título:ß-Klotho as a Negative Regulator of the Peptide Transporters PEPT1 and PEPT2.
[So] Source:Cell Physiol Biochem;40(5):874-882, 2016.
[Is] ISSN:1421-9778
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:BACKGROUND/AIMS: ß-Klotho, a transmembrane protein expressed in several tissues including the brain and the kidney, is critically important for inhibition of 1,25(OH)2D3 formation by FGF23. The extracellular domain of Klotho protein could be cleaved off, thus being released into blood or cerebrospinal fluid. Soluble klotho is a ß-glucuronidase participating in the regulation of several ion channels and carriers. The present study explored the effect of ß-Klotho protein on the peptide transporters PEPT1 and PEPT2. METHODS: cRNA encoding PEPT1 or PEPT2 was injected into Xenopus laevis oocytes and glycine-glycine (2 mM)-induced inward current (IGly) taken as measure of glycine-glycine transport. Measurements were made without or with prior 24 h treatment with soluble ß-Klotho protein (30 ng/ml) in the absence and presence of ß-glucuronidase inhibitor D-saccharic acid 1,4-lactone monohydrate (DSAL,10 µM). Ussing chamber experiments were employed to determine electrogenic peptide transport across intestinal epithelia of klotho deficient (kl-/-) and corresponding wild type (kl+/+) mice. RESULTS: IGly was observed in PEPT1 and in PEPT2 expressing oocytes but not in water injected oocytes. In both, PEPT1 and PEPT2 expressing oocytes IGly was significantly decreased by treatment with soluble ß-Klotho protein. As shown for PEPT1, ß-klotho protein decreased significantly the maximal transport rate without significantly modifying the affinity of the carrier. The effect of ß-Klotho on PEPT1 was reversed by DSAL. Intestinal IGly was significantly larger in kl-/- than in kl+/+ mice. CONCLUSION: ß-Klotho participates in the regulation of the peptide transporters PEPT1 and PEPT2.
[Mh] Termos MeSH primário: Glucuronidase/metabolismo
Simportadores/metabolismo
[Mh] Termos MeSH secundário: Animais
Transporte Biológico/efeitos dos fármacos
Células Epiteliais/efeitos dos fármacos
Células Epiteliais/metabolismo
Glicoproteínas/farmacologia
Glicilglicina/farmacologia
Seres Humanos
Camundongos
Oócitos/efeitos dos fármacos
Oócitos/metabolismo
Transportador 1 de Peptídeos
Proteínas Recombinantes/farmacologia
Xenopus laevis
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycoproteins); 0 (Peptide Transporter 1); 0 (Recombinant Proteins); 0 (Symporters); 0 (beta-glucuronidase inhibitor); 0 (hydrogen-coupled oligopeptide transporter PepT2); 10525P22U0 (Glycylglycine); EC 3.2.1.31 (Glucuronidase); EC 3.2.1.31 (klotho protein)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161213
[St] Status:MEDLINE


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[PMID]:27695788
[Au] Autor:Wang HC; Shi FY; Hou MJ; Fu XY; Long RJ
[Ti] Título:Cloning of oligopeptide transport carrier PepT1 and comparative analysis of PepT1 messenger ribonucleic acid expression in response to dietary nitrogen levels in yak () and indigenous cattle () on the Qinghai-Tibetan plateau.
[So] Source:J Anim Sci;94(8):3431-3340, 2016 Aug.
[Is] ISSN:1525-3163
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The gastrointestinal lumen can directly absorb all di- and tripeptide protein degradation products, and oligopeptide absorption depends on the specific peptide transport carriers, which are located in gastrointestinal epithelial cells on the brush border membrane. Yak () use N more efficiently than cattle do, which implies that yak have a specific mechanism of nonprotein utilization including a peptide absorption mechanism. However, this mechanism has not been clarified. Our objective was to explore whether yak possess any adaptive mechanisms of peptide absorption to survive in the harsh foraging environment of the Qinghai-Tibetan plateau. Twelve castrated males of each of 2 genotypes, yak () and indigenous cattle (), were fed diets of various N levels. The yak PepT1 (yPepT1) cDNA was cloned in omasum epithelial tissue. Our results showed that the full-length yPepT1 cDNA contains 2,805 bp, and a 2,121-bp open reading frame encodes a putative protein of 707 AA residues. The yPepT1 AA sequence identified 5 putative extracellular N-glycosylation sites (Asn, Asn, Asn, Asn, and Asn), 2 putative intracellular protein kinase A sites (Ser and Thr), and 3 intracellular putative protein kinase C sites (Ser, Ser, and Ser). The yPepT1 AA sequence was 99, 95, 86, and 83% identical to PepT1 from cattle (), sheep (), pigs (), and humans (), respectively. The relative PepT1 mRNA expression for indigenous cattle was greater than yak in the rumen, omasum, duodenum, ileum, and liver ( < 0.001); however, it was lower in jejunum tissue ( < 0.01). The relative PepT1 mRNA expression in response to increasing dietary N for both genotypes were linear in the rumen and jejunum ( < 0.10); quadratic or cubic in the reticulum ( < 0.01); linear or quadratic in the duodenum, ileum, and liver ( ≤ 0.01); and linear, quadratic, or cubic in the omasum ( < 0.001). Moreover, there were significant interactions between genotype and dietary N in rumen, reticulum, omasum, duodenum, jejunum, ileum, and liver tissues. In conclusion, the PepT1 profile and expression in gastrointestinal epithelial cells of yak varied from those of cattle, implying that yak have evolved a peptide transport mechanism to adapt the environment of the Qinghai-Tibetan plateau.
[Mh] Termos MeSH primário: Bovinos/metabolismo
Trato Gastrointestinal/metabolismo
Nitrogênio/metabolismo
RNA Mensageiro/metabolismo
Simportadores/metabolismo
[Mh] Termos MeSH secundário: Ração Animal/análise
Fenômenos Fisiológicos da Nutrição Animal
Animais
Transporte Biológico
Bovinos/genética
Dieta/veterinária
Seres Humanos
Masculino
Transportador 1 de Peptídeos
Simportadores/genética
Tibet
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Peptide Transporter 1); 0 (RNA, Messenger); 0 (Symporters); N762921K75 (Nitrogen)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161004
[St] Status:MEDLINE



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