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1.
Front Endocrinol (Lausanne) ; 13: 1013959, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204098

RESUMO

Background: Single-anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S) is one of the most effective bariatric procedures in the treatment of type 2 diabetes mellitus (T2DM). However, the mechanisms by which SADI-S improves T2DM are not well-known. Objective: To explore the effects of SADI-S on metabolites in the stool of rats with T2DM. Methods: Twenty rats were fed on high-fat diet and administered with a low-dose (30mg/kg) of streptozotocin to establish T2DM models. The rats were then randomly assigned to the SADI-S group (n=10) and sham operation group (n=9). Stool samples were collected from all rats at 8 weeks after surgery and stored at -80 °C. Metabolomics analysis was performed to identify differential metabolites through ultra- performance liquid chromatography-mass spectrometry. Results: At 8-week after surgery, rats of the SADI-S group showed significantly decreased fasting blood glucose, glucose tolerance test 2-hour, glycated haemoglobin, and body weight compared with those of the sham group. A total of 245 differential metabolites were identified between the two groups. Among them, 16 metabolites such as branched-chain amino acids (valine), aromatic amino acid (phenylalanine), bile acid (cholic acid, lithocholic acid, and ß-muricholic acid), short-chain fatty acid (isobutyric acid), and phospholipid [lysoPE(17:0), lysoPE(20:3) and lysoPS(16:0)] were associated to the T2DM remission after SADI-S. Conclusion: SADI-S improves T2DM in rats by regulating phenylalanine biosynthesis, valine, phenylalanine, alanine, glutamate, proline, bile acid, and phospholipid metabolism pathways.


Assuntos
Diabetes Mellitus Tipo 2 , Obesidade Mórbida , Animais , Ratos , Alanina , Aminoácidos Aromáticos , Aminoácidos de Cadeia Ramificada , Anastomose Cirúrgica/métodos , Ácidos e Sais Biliares , Glicemia/análise , Diabetes Mellitus Tipo 2/cirurgia , Gastrectomia/métodos , Glutamatos , Hemoglobinas Glicadas/análise , Íleo/química , Íleo/cirurgia , Isobutiratos , Ácido Litocólico , Obesidade Mórbida/cirurgia , Fenilalanina , Fosfolipídeos , Prolina , Estreptozocina , Valina
2.
Bol. latinoam. Caribe plantas med. aromát ; 19(6): 555-568, 2020. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1284299

RESUMO

Despite the development of modern medicine, alternative medicine, which has not lost its timeliness, remains attractive for the treatment of various diseases. Glabridin, a major flavonoid of Glycyrrhiza glabra, is known for its antioxidant and anti-inflammatory activity. The aim of this study was: 1) to determine the possible protective role of glabridin against ischemia/reperfusion (I/R) injury of the intestine; 2) to evaluate the in vitrocontractile responses of ileum smooth muscles to acetylcholine after an intestinal I/R; and 3) to explain the underlying molecular mechanism of its effect. Rats were assigned to groups of six rats each; 1) I/R, 2) gla10, 3) gla20, 4) gla40, 5) N5-[imino(nitroamino)methyl]-L-ornithine, methyl ester monohydrochloride (L-NAME)+gla40, and 6) Sham group. The healing effect of glabridin was abolished by L-NAME. Glabridin did not cause contractility of the smooth muscles to acetylcholine-induced contractile responses in intestinal I/R. Yet, it increased to spontaneous basal activity.


A pesar del desarrollo de la medicina moderna, la medicina alternativa, sin perder su vigencia, sigue siendo atractiva para el tratamiento de varias enfermedades. Glabradina, el flavonoide mayoritario de Glycyrrhiza glabra, es conocido por su actividad antioxidante y antiinflamatoria. Los propósitos de este estudio fueron: 1) Determinar el posible rol protector de glabradina ante daños intestinales por isquemia/reperfusion (I/R) 2) Evaluar in vitrolas respuestas de contracción de los músculos lisos del ileum ante acetilcolina después de I/R intestinal; y 3) Explicar el mecanismo molecular subyacente de este efecto. Se asignaron grupos de seis ratas: 1) I/R, 2) gla10, 3) gla20, 4) gla40, 5) N5-[imino(nitroamino)metil]-L-ornithina, metil ester monohidrochloruro (L-NAME)+gla40, y 6) Grupo testigo. El efecto curativo de glabridina fue abolido por L-NAME. Glabridina no causó contracción en el músculo liso como respuesta acetilcolina-inducida I/R. Además, incrementa la actividad basal expontánea.


Assuntos
Animais , Ratos , Fenóis/administração & dosagem , Traumatismo por Reperfusão/tratamento farmacológico , AMP Cíclico/metabolismo , Glycyrrhiza , Isoflavonas/administração & dosagem , Fenóis/farmacologia , Ratos Wistar , AMP Cíclico/análise , GMP Cíclico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , NG-Nitroarginina Metil Éster , Íleo/efeitos dos fármacos , Íleo/química , Isoflavonas/farmacologia , Malondialdeído/análise , Músculo Liso/efeitos dos fármacos
3.
Health Phys ; 116(4): 516-528, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30624357

RESUMO

Radiation exposure to the gastrointestinal system contributes to the acute radiation syndrome in a dose- and time-dependent manner. Molecular mechanisms that lead to the gastrointestinal acute radiation syndrome remain incompletely understood. Using a murine model of total-body irradiation, C57BL/6J male mice were irradiated at 8, 10, 12, and 14 Gy and assayed at day 1, 3, and 6 after exposure and compared to nonirradiated (sham) controls. Tryptic digests of gastrointestinal tissues (upper ileum) were analyzed by liquid chromatography-tandem mass spectrometry on a Waters nanoLC coupled to a Thermo Scientific Q Exactive hybrid quadrupole-orbitrap mass spectrometer. Pathway and gene ontology analysis were performed with Qiagen Ingenuity, Panther GO, and DAVID databases. A number of trends were identified in our proteomic data including pronounced protein changes as well as protein changes that were consistently up regulated or down regulated at all time points and dose levels interrogated. Time- and dose-dependent protein changes, canonical pathways affected by irradiation, and changes in proteins that serve as upstream regulators were also identified. Additionally, proteins involved in key processes including inflammation, radiation, and retinoic acid signaling were identified. The proteomic profiling conducted here represents an untargeted systems biology approach to identify acute molecular events that will be useful for a greater understanding of animal models and may be potentially useful toward the development of medical countermeasures and/or biomarkers.


Assuntos
Síndrome Aguda da Radiação/metabolismo , Trato Gastrointestinal/efeitos da radiação , Proteômica , Lesões Experimentais por Radiação/metabolismo , Animais , Biomarcadores/análise , Cromatografia Líquida , Relação Dose-Resposta à Radiação , Trato Gastrointestinal/metabolismo , Íleo/química , Íleo/metabolismo , Íleo/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/etiologia , Espectrometria de Massas em Tandem , Irradiação Corporal Total
4.
Acta Histochem ; 120(8): 728-733, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30107890

RESUMO

The effects of bisphenol A on the some plasma cytokine levels and distribution of CD8+ and CD4+ T lymphocytes in spleen, ilealPeyer's patch and bronchus-associated lymphoid tissue in rats were investigated. A total of fourty male Wistar Albino rats were divided into five groups including 8 rats in each one: control, vehicle, BPA 5, BPA 50 and BPA 500 groups. Doses of 5, 50 and 500 µg/kg BPA were dissolved in ethanol, then mixed with corn oil. The control group received no treatment. The vehicle group was given the ethanol-corn oil mixture. BPA 5, BPA 50 and BPA 500 groups were given, respectively, 5, 50, and 500 µg/kg/day orally. In blood samples, IL-4, IL-6, IL-10 and TNF-α plasma levels were determined with ELISA. Tissue samples (spleen, ileal Peyer's patches and lung) were processed by means of routine histological techniques. CD4 and CD8 were stained immunohistochemically. Data obtained from this study showed that, BPA causes the alteration on immune parameters including cytokine profile, distribution of CD8+ and CD4+ T lymhpocytes in spleen and ileal Peyer's patches. Present study indicated that BPA may affect immune systems even at lower doses.Disruption of immun system cells and cytokine levels can result in harmful outcomes triggering autoimmune diseases and immunodeficiencies.


Assuntos
Compostos Benzidrílicos/farmacologia , Brônquios/química , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Íleo/química , Nódulos Linfáticos Agregados/efeitos dos fármacos , Fenóis/farmacologia , Baço/química , Administração Oral , Animais , Brônquios/imunologia , Ensaio de Imunoadsorção Enzimática , Íleo/imunologia , Interleucina-4/sangue , Masculino , Ratos , Ratos Endogâmicos WF , Padrões de Referência , Baço/imunologia , Fator de Necrose Tumoral alfa/sangue
5.
Hum Pathol ; 79: 42-49, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29555578

RESUMO

Intestinal stricture, a major complication of Crohn's disease (CD), results from fibromuscular remodeling and expansion of the intestinal wall. The corresponding microanatomical alterations have not been fully described, hindering progress toward understanding their pathogenesis and devising appropriate treatments. We used tissue-specific staining and quantitative digital histomorphometry for this purpose. Serial histologic sections from 37 surgically resected ileal strictures and adjacent nonstrictured controls from patients with CD were evaluated after staining for smooth muscle actin, collagen (Sirius red), and collagen types I, III, and V. Overall mural thickening in strictures was increased 2.2 ±â€¯0.2-fold compared with nonstrictured regions of the same specimens. The muscular layer most altered was the muscularis mucosae (MM). Compared with the internal and external layers of the muscularis propria, (MP) which were expanded 1.9 ±â€¯0.2- and 1.3 ±â€¯0.1-fold, respectively, the MM was expanded 17.7 ±â€¯2.6-fold, reflecting the combined effects of architectural disarray, an 11.6 ±â€¯1.4-fold increase smooth muscle content, and elaboration of pericellular type V collagen. In contrast, the architecture of the MP was preserved and pericellular collagen was virtually absent; rather, fibrosis in this layer was limited to expansion of the intramuscular septa by collagen types I and III. The muscular arteries and veins within the strictured submucosa frequently exhibited eccentric, luminally oriented adventitial mantles comprising hyperplastic myocytes and extracellular type V collagen. We conclude that the fibromuscular remodeling which results in CD-associated ileal strictures predominantly involves the MM and submucosal vasculature in a luminally polarized fashion and suggests that mucosal-based factors may contribute to stricture pathogenesis.


Assuntos
Polaridade Celular , Doença de Crohn/patologia , Íleo/patologia , Mucosa Intestinal/patologia , Músculo Liso/patologia , Remodelação Vascular , Actinas/análise , Adolescente , Adulto , Idoso , Biomarcadores/análise , Estudos de Casos e Controles , Colágeno/análise , Constrição Patológica , Doença de Crohn/metabolismo , Doença de Crohn/cirurgia , Feminino , Humanos , Hiperplasia , Íleo/irrigação sanguínea , Íleo/química , Íleo/cirurgia , Mucosa Intestinal/irrigação sanguínea , Mucosa Intestinal/química , Mucosa Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Músculo Liso/irrigação sanguínea , Músculo Liso/química , Músculo Liso/cirurgia , Adulto Jovem
7.
Glycobiology ; 27(3): 246-253, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28177462

RESUMO

In this study, we examined the distribution of fucosylated glycans in mouse intestines using a lectin, BC2LCN (N-terminal domain of the lectin BC2L-C from Burkholderia cenocepacia), as a probe. BC2LCN is specific for glycans with a terminal Fucα1,2Galß1,3-motif and it is a useful marker for discriminating the undifferentiated status of human induced/embryonic stem cells. Apparent BC2LCN reactivity was detected in the secretory granules of goblet cells in the ileum but not those in the colon. We also found distinctive reactivity in the crypt bottom, which is known as the stem cell zone, of the colon and the ileum. Other lectins for fucosylated glycans, including Ulex europaeus agglutinin-I, Pholiota squarrosa lectin and Aleuria aurantia lectin, did not exhibit similar reactivity in the crypt bottom. Remarkably, BC2LCN-positive epithelial cells could be labeled with a niche cell marker, c-Kit/CD117. Overall, our results indicate that intestinal niche cells express distinct fucosylated glycans recognized by BC2LCN. Increasing evidence suggests that the self-renewal and proliferation of stem cells depend on specific signals derived from niche cells. Our results highlight novel molecular properties of intestinal niche cells in terms of their glycosylation, which may help to understand the regulation of intestinal stem cells. The distinct expression of glycans may reflect the functional roles of niche cells. BC2LCN is a valuable tool for investigating the functional significance of protein glycosylation in stem cell regulation.


Assuntos
Linhagem da Célula/genética , Lectinas/química , Polissacarídeos/isolamento & purificação , Proteínas Proto-Oncogênicas c-kit/metabolismo , Animais , Burkholderia cenocepacia/química , Colo/química , Colo/citologia , Células Caliciformes/química , Células Caliciformes/metabolismo , Íleo/química , Íleo/citologia , Camundongos , Células-Tronco Embrionárias Murinas/química , Células-Tronco Embrionárias Murinas/metabolismo , Polissacarídeos/química , Polissacarídeos/genética , Proteínas Proto-Oncogênicas c-kit/isolamento & purificação , Nicho de Células-Tronco/genética
8.
J Proteomics ; 140: 37-47, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27040117

RESUMO

UNLABELLED: Echinostoma caproni (Trematoda: Echinostomatidae) is an intestinal trematode, which has been widely employed to investigate the factors determining the rejection of intestinal helminths. Protein production patterns of intestinal epithelial cells are related to the infection-induced changes that determine the course of E. caproni infections. Herein, we compare the protein production profiles in the ileum of four experimental groups of mice: control; infected; dewormed and reinfected. Worm burdens were significantly lower in secondary infections, confirming the generation of partial resistance to homologous secondary infections in mice. However, quantitative comparison by 2D-DIGE showed that the protein production profile is similar in control and dewormed mice, and after primary and secondary E. caproni infections. These results showed that, unexpectedly, protein production changes in E. caproni infections are not responsible of resistance development. Fifty-one protein spots were differentially produced between control/treated and infected/reinfected mice and 37 of them were identified by mass spectrometry. The analysis of differentially abundant proteins indicate that cell metabolism and the regulation of proliferation and cell death are the most affected processes after primary and secondary E. caproni infections. These results provide new insights into the proteins involved in the regulation of tissue homeostasis after intestinal infection. SIGNIFICANCE: Intestinal helminthiases are highly prevalent parasitic infections with about 1 billion people infected worldwide. In this scenario, better understanding of host-parasite relationships is needed to elucidate the factors that determine intestinal helminth rejection. The intestinal trematode Echinostoma caproni has been broadly employed in this field, with resistance against secondary homologous infections reported in mice. In this paper, new insights are provided in the regulation of tissue homeostasis after intestinal infection. The unexpected lack of an altered pattern of ileal protein production associated to resistance development suggests that this resistance depends on rapid changes, affecting the early establishment of worms, rather than the activation of later effector mechanisms. These results may contribute to the development of new control tools for the management of these parasitic infections.


Assuntos
Resistência à Doença , Echinostoma/patogenicidade , Equinostomíase/imunologia , Íleo/metabolismo , Animais , Morte Celular , Proliferação de Células , Coinfecção/imunologia , Coinfecção/parasitologia , Coinfecção/patologia , Equinostomíase/patologia , Células Epiteliais/química , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Íleo/química , Íleo/parasitologia , Íleo/patologia , Espectrometria de Massas , Camundongos , Biossíntese de Proteínas
9.
Sci Rep ; 6: 22875, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26960718

RESUMO

Oxidized human defensin 5 (HD5OX), a Paneth cell-secreted antibacterial peptide with three characteristic disulfide bonds, protects the host from invasion by morbigenous microbes in the small intestine. HD5OX can be reduced by thioredoxin (Trx) in vitro, while the biochemical properties of the reduced linear peptide, HD5RED, remain unclear. Here, we first confirm that HD5RED does exist in vivo. Furthermore, we reveal that the recruitment of HD5RED to the outer membrane of Gram-negative bacteria and to the anionic lipid A is lower than that of HD5OX, and HD5RED is less efficient in penetrating bacterial outer and inner membranes and inducing membrane depolarization, which confers an attenuated antibacterial activity to HD5RED. However, due to its higher structural flexibility, the binding of HD5RED to bacterial lipopolysaccharide (LPS) is markedly stronger than that of HD5OX. Consequently, HD5RED is more effective in suppressing the production of the pro-inflammatory cytokine TNF-α in LPS-stimulated macrophages by blocking the interaction between LPS and LPS-binding protein, thus suggesting that HD5RED might act as a scavenger to neutralize LPS in the gut. This study provides insights into the antibacterial and immunoregulatory effects of HD5RED and expands the known repertoire of the enteric defensins.


Assuntos
Lipopolissacarídeos/farmacologia , alfa-Defensinas/metabolismo , Proteínas de Fase Aguda/metabolismo , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Líquidos Corporais/química , Proteínas de Transporte/metabolismo , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Humanos , Íleo/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Oxirredução , Ligação Proteica , Salmonella typhimurium/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , alfa-Defensinas/química , alfa-Defensinas/farmacologia
10.
J Gastrointestin Liver Dis ; 25(1): 39-48, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27014752

RESUMO

BACKGROUND AND AIMS: Angiotensin II (AII) is a powerful splanchnic vasoconstrictor with pro-inflammatory and pro-fibrotic properties. Angiotensin converting enzyme (ACE) inhibitors and AII Receptor Antagonists (ARBs) are therapeutic in animal models of colitis. The aim of this case-control study is to determine the expression of angiotensinogen and related genes in human ileal Crohn's disease. METHODS: Using quantitative real-time polymerase chain reaction (RT-PCR), we measured mRNA expression levels of angiotensinogen (AGT), hypoxia inducible factor (HIF)1α and melanoma cell adhesion molecule (MCAM; CD146) in 101 human samples (69 biopsy, 12 resection) from affected ileum (inflamed CD cases, n=36) and unaffected ileum (non-inflamed CD cases, n=45 and controls, n=20). Immunohistochemistry for angiotensinogen was also performed. The study was of case-control design in a tertiary care setting. RESULTS: Ileal expression of AGT was lower in CD cases compared to controls (p<0.0001), in inflamed CD samples (p=0.017) and current smokers (p=0.02). HIF1α expression was lower in non-inflamed CD biopsy samples than controls (p=0.006). The presence of disease-associated NOD2 variants was associated with increased expression of markers of angiogenesis (HIF1α p=0.009; MCAM p=0.007) in inflamed CD samples. Angiotensinogen immunohistochemical staining supported the quantitative RT-PCR expression findings. CONCLUSIONS: Angiotensinogen expression is down regulated in human ileal CD, particularly in the presence of inflammation and current cigarette smoking, implicating the mesenteric vasculature and mucosal hypoxia as co-factors in ileal CD pathogenesis. A novel reduction in HIF1α expression in non-inflamed ileal mucosa in CD patients was also demonstrated.


Assuntos
Proteínas Angiogênicas/análise , Angiotensinogênio/análise , Doença de Crohn/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Íleo/química , Neovascularização Patológica , Adulto , Idoso , Proteínas Angiogênicas/genética , Angiotensinogênio/genética , Antígeno CD146/genética , Estudos de Casos e Controles , Doença de Crohn/genética , Doença de Crohn/patologia , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Íleo/patologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Proteína Adaptadora de Sinalização NOD2/genética , Fenótipo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Fumar/efeitos adversos , Adulto Jovem
11.
World J Gastroenterol ; 21(35): 10080-90, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26401073

RESUMO

AIM: To investigate whether accelerated catabolism of ganglioside and decreased ganglioside content contribute to the etiology of pro-inflammatory intestinal disease. METHODS: Intestinal mucosa from terminal ileum or colon was obtained from patients with ulcerative colitis or inflammatory Crohn's disease (n = 11) undergoing bowel resection and compared to control samples of normal intestine from patients with benign colon polyps (n = 6) and colorectal cancer (n = 12) in this observational case-control study. Gangliosides and phospholipids of intestinal mucosa were characterized by class and ceramide or fatty acid composition using liquid chromatography triple-quad mass spectrometry. Content and composition of ganglioside classes GM1, GM3, GD3, GD1a, GT1 and GT3 were compared among subject groups. Content and composition of phospholipid classes phosphatidylcholine (PC) and phosphatidylethanolamine were compared among subject groups. Unsaturation index of individual ganglioside and phospholipid classes was computed and compared among subject groups. Ganglioside catabolism enzymes beta-hexosaminidase A (HEXA) and sialidase-3 (NEU3) were measured in intestinal mucosa using western blot and compared among subject groups. RESULTS: Relative GM3 ganglioside content was 2-fold higher (P < 0.05) in intestine from patients with inflammatory bowel disease (IBD) compared to control intestine. The quantity of GM3 and ratio of GM3/GD3 was also higher in IBD intestine than control tissue (P < 0.05). Control intestine exhibited 3-fold higher (P < 0.01) relative GD1a ganglioside content than IBD intestine. GD3 and GD1a species of ganglioside containing three unsaturated bonds were present in control intestine, but were not detected in IBD intestine. The relative content of PC containing more than two unsaturated bonds was 30% lower in IBD intestine than control intestine (P < 0.05). The relative content of HEXA in IBD intestine was increased 1.7-fold (P < 0.05) and NEU3 was increased 8.3-fold (P < 0.01) compared to normal intestine. Intestinal mucosa in IBD is characterized by increased GM3 content, decreased GD1a, and a reduction in polyunsaturated fatty acid constituents in GD3, GD1a and PC. CONCLUSION: This study suggests a new paradigm by proposing that IBD occurs as a consequence of increased metabolism of specific gangliosides.


Assuntos
Colite Ulcerativa/metabolismo , Colo/química , Doença de Crohn/metabolismo , Ácidos Graxos Insaturados/análise , Gangliosídeos/análise , Íleo/química , Mucosa Intestinal/química , Estudos de Casos e Controles , Colite Ulcerativa/cirurgia , Colo/cirurgia , Doença de Crohn/cirurgia , Gangliosídeo G(M3)/análise , Humanos , Íleo/cirurgia , Mucosa Intestinal/cirurgia , Neuraminidase/análise , Fosfatidilcolinas/análise , Fosfatidiletanolaminas/análise , Cadeia alfa da beta-Hexosaminidase/análise
12.
J Pharm Biomed Anal ; 110: 27-33, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-25796981

RESUMO

Transporter proteins expressed in the gastrointestinal tract play a major role in the oral absorption of some drugs, and their involvement may lead to drug-drug interaction (DDI) susceptibility when given in combination with drugs known to inhibit gut wall transporters. Anticipating such liabilities and predicting the magnitude of the impact of transporter proteins on oral drug absorption and DDIs requires quantification of their expression in human intestine, and linking these to data obtained through in vitro experiments. A quantitative targeted absolute proteomic method employing liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) together with a quantitative concatenation (QconCAT) strategy to provide proteotypic peptide standards has been applied to quantify ATP1A1 (sodium/potassium-ATPase; Na/K-ATPase), CDH17 (human peptide transporter 1; HPT1), ABCB1 (P-glycoprotein; P-gp), ABCG2 (breast cancer resistance protein; BCRP), ABCC2 (multidrug resistance-associated protein 2; MRP2) and SLC51A (Organic Solute Transporter subunit alpha; OST-α), in human distal jejunum (n=3) and distal ileum (n=1) enterocyte membranes. Previously developed selected reaction monitoring (SRM) schedules were optimised to enable quantification of the proteotypic peptides for each transporter. After harvesting enterocytes by calcium chelation elution and generating a total membrane fraction, the proteins were subjected to proteolytic digestion. To account for losses of peptides during the digestion procedure, a gravimetric method is also presented. The linearity of quantifying the QconCAT from an internal standard (correlation coefficient, R(2)=0.998) and quantification of all target peptides in a pooled intestinal quality control sample (R(2)≥ 0.980) was established. The assay was also assessed for within and between-day precision, demonstrating a <15% coefficient of variation for all peptides across 3 separate analytical runs, over 2 days. The methods were applied to obtain the absolute abundances for all targeted proteins. In all samples, Na/K-ATPase, HPT1, P-gp and BCRP were detected above the lower limit of quantitation (i.e., >0.2 fmol/µg membrane protein). MRP2 abundance could be quantified in distal jejunum but not in the distal ileum sample. OST-α was not detected in 2 out of 3 jejunum samples. This study highlights the utility of a QconCAT strategy to quantify absolute transporter abundances in human intestinal tissues.


Assuntos
Cromatografia Líquida , Íleo/química , Jejuno/química , Proteínas de Membrana Transportadoras/análise , Proteômica/métodos , Espectrometria de Massas em Tandem , Calibragem , Membrana Celular/química , Cromatografia Líquida/normas , Enterócitos/química , Humanos , Íleo/citologia , Jejuno/citologia , Modelos Lineares , Proteína 2 Associada à Farmacorresistência Múltipla , Proteômica/normas , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/normas
13.
Eur J Gastroenterol Hepatol ; 27(5): 570-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25822866

RESUMO

BACKGROUND: Bacterial translocation (BT) related to intestinal bacterial overgrowth (IBO) plays an important role in the pathogenesis of bacterial infections in cirrhosis. Inhibition of acid gastric secretion promotes IBO and might favor BT. We evaluated the effect of long-term inhibition of acid gastric secretion on BT in cirrhotic rats. METHODS: Cirrhotic rats with and without ascites induced by oral CCl4 and controls were randomized to treatment with a daily subcutaneous injection of placebo, ranitidine (50 mg/kg), or pantoprazole (8 mg/kg) during 2 weeks. Continuous pH-metry was performed for 2 h before and at the end of treatment; thereafter, a laparotomy to obtain samples of blood, mesenteric lymph nodes, ascites, spleen, liver, and cecal stools was performed. RESULTS: Ranitidine and pantoprazole increased gastric pH as compared with placebo (P<0.001). However, antisecretory drugs increased the incidence of BT only in ascitic rats treated with ranitidine (P<0.05) or pantoprazole (P=0.07) when compared with placebo-treated ascitic rats or cirrhotic rats without ascites treated with the same drug. Cirrhotic ascitic rats treated with pantoprazole showed a trend toward an increased incidence of IBO (P=0.08), a higher ileal malondialdehyde level (P<0.01), and an increased production of tumor necrosis factor-α (P<0.05). CONCLUSION: Although inhibition of acid gastric secretion increased gastric pH in all animals, the incidence of BT increased only in ascitic rats, and it was associated with a trend toward an increase in IBO incidence, a higher ileal malondialdehyde level, and an increased production of serum tumor necrosis factor-α. Therefore, antisecretory drugs should be carefully administered to cirrhotic ascitic patients.


Assuntos
Antiulcerosos/farmacologia , Translocação Bacteriana/efeitos dos fármacos , Síndrome da Alça Cega/microbiologia , Ácido Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Cirrose Hepática Experimental/complicações , 2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Animais , Ascite/etiologia , Síndrome da Alça Cega/induzido quimicamente , Ácido Gástrico/química , Mucosa Gástrica/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Íleo/química , Mucosa Intestinal/química , Mucosa Intestinal/efeitos dos fármacos , Cirrose Hepática Experimental/sangue , Masculino , Malondialdeído/análise , Pantoprazol , Ranitidina/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue
14.
Biomed Res Int ; 2014: 984756, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25114933

RESUMO

Aim of present study was to develop a solid nanoemulsion preconcentrate of paclitaxel (PAC) using oil [propylene glycol monocaprylate/glycerol monooleate, 4:1 w/w], surfactant [polyoxyethylene 20 sorbitan monooleate/polyoxyl 15 hydroxystearate, 1:1 w/w], and cosurfactant [diethylene glycol monoethyl ether/polyethylene glycol 300, 1:1 w/w] to form stable nanocarrier. The prepared formulation was characterized for droplet size, polydispersity index, and zeta potential. Transmission electron microscopy (TEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to assess surface morphology and drug encapsulation and its integrity. Cumulative drug release of prepared formulation through dialysis bag and permeability coefficient through everted gut sac were found to be remarkably higher than the pure drug suspension and commercial intravenous product (Intaxel), respectively. Solid nanoemulsion preconcentrate of PAC exhibited strong inhibitory effect on proliferation of MCF-7 cells in MTT assay. In vivo systemic exposure of prepared formulation through oral administration was comparable to that of Intaxel in γ scintigraphy imaging. Our findings suggest that the prepared solid nanoemulsion preconcentrate can be used as an effective oral solid dosage form to improve dissolution and bioavailability of PAC.


Assuntos
Portadores de Fármacos/química , Emulsões/química , Nanopartículas/química , Paclitaxel/química , Paclitaxel/farmacocinética , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica/métodos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Estabilidade de Medicamentos , Emulsões/administração & dosagem , Emulsões/farmacocinética , Emulsões/toxicidade , Feminino , Íleo/química , Íleo/metabolismo , Células MCF-7 , Nanopartículas/administração & dosagem , Nanopartículas/toxicidade , Paclitaxel/administração & dosagem , Paclitaxel/toxicidade , Cintilografia , Ratos , Ratos Wistar , Distribuição Tecidual
15.
J Agric Food Chem ; 62(30): 7631-41, 2014 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-24998385

RESUMO

The (poly)phenols in ileal fluid after ingestion of raspberries were analyzed by targeted and nontargeted LC-MS(n) approaches. Targeted approaches identified major anthocyanin and ellagitannin components at varying recoveries and with considerable interindividual variation. Nontargeted LC-MS(n) analysis using an orbitrap mass spectrometer gave exact mass MS data which were sifted using a software program to select peaks that changed significantly after supplementation. This method confirmed the recovery of the targeted components but also identified novel raspberry-specific metabolites. Some components (including ellagitannin and previously unidentified proanthocyanidin derivatives) may have arisen from raspberry seeds that survived intact in ileal samples. Other components include potential breakdown products of anthocyanins, unidentified components, and phenolic metabolites formed either in the gut epithelia or after absorption into the circulatory system and efflux back into the gut lumen. The possible physiological roles of the ileal metabolites in the large bowel are discussed.


Assuntos
Íleo/química , Polifenóis/análise , Rubus/química , Adulto , Antocianinas/análise , Antocianinas/farmacocinética , Cromatografia Líquida , Feminino , Humanos , Concentração de Íons de Hidrogênio , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacocinética , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Extratos Vegetais/análise , Extratos Vegetais/farmacocinética , Polifenóis/farmacocinética , Sementes/química
16.
World J Gastroenterol ; 20(9): 2383-91, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24605036

RESUMO

AIM: To study the ileal endocrine cell types in irritable bowel syndrome (IBS) patients. METHODS: Ninety-eight patients with IBS (77 females and 21 males; mean age 35 years, range 18-66 years) were included, of which 35 patients had diarrhea (IBS-D), 31 patients had a mixture of both diarrhea and constipation (IBS-M), and 32 patients had constipation (IBS-C) as the predominant symptoms. The controls were 38 subjects (26 females and 12 males; mean age 40 years, range 18-65 years) who had submitted to colonoscopy for the following reasons: gastrointestinal bleeding, where the source of bleeding was identified as hemorrhoids (n = 24) or angiodysplasia (n = 3), and health worries resulting from a relative being diagnosed with colon carcinoma (n = 11). The patients were asked to complete the: Birmingham IBS symptom questionnaire. Ileal biopsy specimens from all subjects were immunostained using the avidin-biotin-complex method for serotonin, peptide YY (PYY), pancreatic polypeptide (PP), enteroglucagon, and somatostatin cells. The cell densities were quantified by computerized image analysis, using Olympus cellSens imaging software. RESULTS: The gender and age distributions did not differ significantly between the patients and the controls (P = 0.27 and P = 0.18, respectively). The total score of Birmingham IBS symptom questionnaire was 21 ± 0.8, and the three underlying dimensions: pain, diarrhea, and constipation were 7.2 ± 0.4, 6.6 ± 0.4, and 7.2 ± 0.4, respectively. The density of serotonin cells in the ileum was 40.6 ± 3.6 cells/mm² in the controls, and 11.5 ± 1.2, 10.7 ± 5.6, 10.0 ± 1.9, and 13.9 ± 1.4 cells/mm² in the all IBS patients (IBS-total), IBS-D, IBS-M, and IBS-C patients, respectively. The density in the controls differed significantly from those in the IBS-total, IBS-D, IBS-M, and IBS-C groups (P < 0.0001, P = 0.0001, P = 0.0001, and P < 0.0001, respectively). There was a significant inverse correlation between the serotonin cell density and the pain dimension of Birmingham IBS symptom questionnaire (r = -0.6, P = 0.0002). The density of PYY cells was 26.7 ± 1.6 cells/mm(2) in the controls, and 33.1 ± 1.4, 27.5 ± 1.4, 34.1 ± 2.5, and 41.7 ± 3.1 cells/mm² in the IBS-total, IBS-D, IBS-M, and IBS-C patients, respectively. This density differed significantly between patients with IBS-total and IBS-C and the controls (P = 0.03 and < 0.0001, respectively), but not between controls and, IBS-D, and IBS-M patients (P = 0.8, and P = 0.1, respectively). The density of PYY cells correlated significantly with the degree of constipation as recorded by the Birmingham IBS symptom questionnaire (r = 0.6, P = 0.0002). There were few PP-, enteroglucagon-, and somatostatin-immunoreactive cells in the biopsy material examined, which made it impossible to reliably quantify these cells. CONCLUSION: The decrease of ileal serotonin cells is associated with the visceral hypersensitivity seen in all IBS subtypes. The increased density of PYY cells in IBS-C might contribute to the constipation experienced by these patients.


Assuntos
Células Endócrinas/patologia , Íleo/patologia , Síndrome do Intestino Irritável/patologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Biópsia , Estudos de Casos e Controles , Colonoscopia , Constipação Intestinal/etiologia , Diarreia/etiologia , Células Endócrinas/química , Feminino , Peptídeos Semelhantes ao Glucagon/análise , Humanos , Hiperalgesia/etiologia , Íleo/química , Interpretação de Imagem Assistida por Computador , Imuno-Histoquímica , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/metabolismo , Masculino , Pessoa de Meia-Idade , Medição da Dor , Polipeptídeo Pancreático/análise , Peptídeo YY/análise , Serotonina/análise , Somatostatina/análise , Células Secretoras de Somatostatina/química , Células Secretoras de Somatostatina/patologia , Inquéritos e Questionários , Dor Visceral/etiologia , Adulto Jovem
17.
J Pediatr Gastroenterol Nutr ; 58(4): 477-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24164906

RESUMO

OBJECTIVES: The base of human Peyer patches of the terminal ileum has been noted to contain black granular pigment deposits, composed of titanium dioxide and aluminosilicate, which are food additives typically present in a Western diet, and pharmaceuticals. In the present study, we investigated the distribution of exogenous pigment throughout the gastrointestinal tract of children suspected of having inflammatory bowel disease (IBD), the correlation between their age and the presence and amount of pigment in Peyer patches, and its relation to pediatric IBD. METHODS: Biopsies (upper and lower gastrointestinal tract) from children suspected of having IBD who underwent endoscopy, were reassessed by a blinded, expert pathologist. The amount of pigment in biopsies was scored using a semiquantitative scale (range 0 to +++). RESULTS: A total of 151 children were included: 62 with Crohn disease (CD), 26 with ulcerative colitis, and 63 with non-IBD. In 63 children (42%), deposits of black pigment were found only in biopsies from the terminal ileum, located in Peyer patches. A significant correlation was found between increasing age and the amount of pigment (P = 0.004). Pigment deposits were found significantly less in the patients with CD compared with those in patients with ulcerative colitis and those with non-IBD (26% vs 62% and 49%, P = 0.002). CONCLUSIONS: These results provide support for the hypothesis that the amount of pigment, only present in Peyer patches in the terminal ileum, becomes denser with increasing age. Absence of pigment in Peyer patches in a higher number of patients with CD suggests that microparticles may have become involved in the inflammatory process, possibly because of disrupted autophagy.


Assuntos
Colite Ulcerativa/patologia , Corantes/análise , Doença de Crohn/patologia , Íleo/química , Nódulos Linfáticos Agregados/química , Adolescente , Fatores Etários , Biópsia , Criança , Pré-Escolar , Endoscopia Gastrointestinal , Feminino , Humanos , Íleo/patologia , Lactente , Masculino , Nódulos Linfáticos Agregados/patologia
18.
Clin Lab ; 60(12): 1993-2000, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25651733

RESUMO

BACKGROUND: Children with suspected bowel inflammation require an invasive endoscopic procedure, which is usually performed under general anesthesia. To improve the selection of candidates for endoscopy, fecal calprotectin level has been proposed as a noninvasive marker of intestinal inflammation. In the future, home testing is a likely option. Thus, the aim of this study was to affirm the association between bedside-measured fecal calprotectin concentration and histological and endoscopic findings in a panel of patients with suspected chronic bowel inflammation. METHODS: Stool samples and microscopic and macroscopic findings from 41 patients, who underwent ileocolonoscopy for suspicion of bowel inflammation, were consecutively obtained between April 2009 and December 2010. Stool samples were analyzed using the bedside fecal calprotectin enzyme-linked immunosorbent assay (Quantum Blue; Bühlmann, Laboratories AG, Switzerland). RESULTS: Fecal calprotectin levels were elevated in 18 children with bowel inflammation on endoscopy (median at the upper limit of undiluted samples, 300 µg/g) compared with 23 children without bowel inflammation (median, 105 µg/g; p < 0.00097). Similarly, the fecal calprotectin level was elevated in 25 children with positive histological findings as assessed by a pathologist (median, 300 µg/g) compared with 16 children without histological inflammation (median, 73 µg/g; p < 0.000014). Based on the optimal area under the curve, we calculated the cutoff fecal calprotectin level for bowel inflammation on endoscopy as 167 µg/g (area under the curve, 0.86; 95% confidence interval (CI), 0.81 - 0.92) and on histological examination as 280 µg/g (area under the curve, 0.78; 95% CI, 0.70 - 0.86). Fecal calprotectin level was more sensitive than endoscopy for diagnosis of microscopic bowel inflammation (p = 0.000014). CONCLUSIONS: Our results clearly show that even the bedside test for fecal calprotectin level, using the optimal cut-off value, is feasible enough in determining candidates for an endoscopic procedure in order to confirm bowel inflammation and is more tightly associated with histological findings than with endoscopic findings. Thus, the calprotectin level reflects histological activity, even in cases with normal endoscopic findings. The bedside test described herein is a sufficient screening method for this purpose.


Assuntos
Colo , Colonoscopia , Fezes/química , Íleo , Mediadores da Inflamação/análise , Doenças Inflamatórias Intestinais/diagnóstico , Complexo Antígeno L1 Leucocitário/análise , Sistemas Automatizados de Assistência Junto ao Leito , Adolescente , Fatores Etários , Área Sob a Curva , Biomarcadores/análise , Estudos de Casos e Controles , Criança , Pré-Escolar , Colo/química , Colo/imunologia , Colo/patologia , Estudos de Viabilidade , Feminino , Humanos , Íleo/química , Íleo/imunologia , Íleo/patologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Masculino , Valor Preditivo dos Testes , Curva ROC , Regulação para Cima
19.
Int J Surg ; 11(1): 27-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23164988

RESUMO

INTRODUCTION: Bacterial translocation occurs when intestinal mucosa and the intestinal wall lose their barrier properties against bacteria such as in the case of intestinal obstruction. Enteral nutrition with immunonutrients strengthens the immune system and thickens the intestinal barrier thus preventing bacterial translocation. AIM: The purpose of this study is to investigate the effect of uracil which is an immunonutrient on bacterial translocation using rats with intestinal obstruction as a model. METHODS: Wistar albino rats were divided into three groups. The control group was fed with standard chow diet, while the other two groups were fed with uracil-supplemented chow diet. The rats were fed with these diets for seven days. And the end of the feeding period all groups were submitted intestinal obstruction and injected with (99m)Tc labeled Escherichia coli into the rats' terminal ileum under anesthetic. The rats were sacrificed 24 h later. Their blood, mesenteric lymph nodes (MLN), liver, spleen, lung and ileum were removed to determine level of radioactivity. RESULTS: When compared with the control group it was determined that uracil supplementation reduced the level of bacterial translocation. CONCLUSION: Uracil may be used in the prevention of bacterial translocation in cases of intestinal obstruction because it strengthens the intestinal barrier and the immune system. However, more studies are needed to clearly explain the mechanism behind uracil's beneficial role here.


Assuntos
Translocação Bacteriana/efeitos dos fármacos , Obstrução Intestinal/microbiologia , Uracila/farmacologia , Análise de Variância , Animais , Técnicas de Diagnóstico por Radioisótopos , Modelos Animais de Doenças , Escherichia coli/química , Escherichia coli/fisiologia , Íleo/química , Íleo/metabolismo , Íleo/patologia , Obstrução Intestinal/diagnóstico por imagem , Masculino , Cintilografia , Distribuição Aleatória , Ratos , Ratos Wistar , Tecnécio/análise , Distribuição Tecidual
20.
Glycobiology ; 22(12): 1721-30, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22833314

RESUMO

A 6-cm fresh proximal ileum surgical specimen from a blood group A(1)Le(a-b+) secretor individual was used for stepwise isolation of epithelial cells from villus tip to crypt bottom by gentle washing with ethylenediaminetetraacetic acid-containing buffer. Acid and non-acid sphingolipids were prepared from the epithelial cell fractions and the non-epithelial intestinal residue. Molecular information on the sphingolipid composition was obtained without further isolation of individual species by applying thin-layer chromatography using chemical and biological (monoclonal antibodies, cholera toxin, Escherichia coli) detection reagents, mass spectrometry and proton NMR spectroscopy of derivatized glycolipids. In this way, the structure of major and minor saccharides, ceramide components and their relative amounts were obtained. Epithelial cells and non-epithelial residue were distinctly different in their sphingolipid composition. Sphingomyelin was the major single component in both compartments. Characteristic for epithelial cells was the dominance of monoglycosylceramides, sulphatides and blood group fucolipids (mainly Le(b) hexaglycosylceramides and ALe(b) heptaglycosylceramides). The non-epithelial residue had about five times less glycolipids mainly mono-, di-, tri- and tetra-glycosylceramides and gangliosides, including the GM1 ganglioside. The ceramides were more hydroxylated (1-2 additional hydroxyls) in epithelial cell glycolipids compared with the non-epithelial residue. Combined with a separate detailed study on the glycoproteins of the same epithelial cell preparation, this human intestinal sample is the only epithelial cell preparation where both protein- and lipid-linked saccharides are characterized in detail.


Assuntos
Íleo/química , Mucosa Intestinal/química , Esfingomielinas/análise , Ceramidas/análise , Células Epiteliais/química , Feminino , Gangliosídeo G(M1)/análise , Glicolipídeos/análise , Humanos , Íleo/citologia , Mucosa Intestinal/citologia , Microvilosidades/química , Pessoa de Meia-Idade
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