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1.
Diabetes Res Clin Pract ; 184: 109194, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35032562

RESUMO

AIMS: Duodenal mucosal resurfacing (DMR) is an endoscopic procedure developed to improve metabolic parameters and restore insulin sensitivity in patients with diabetes. Here we report long-term DMR safety and efficacy from the REVITA-1 study. MATERIALS AND METHODS: REVITA-1 was a prospective, single-arm, open-label, multicenter study of DMR feasibility, safety, and efficacy in patients with type 2 diabetes (hemoglobin A1c [HbA1c] of 7.5-10.0% (58-86 mmol/mol)) on oral medication. Safety and glycemic (HbA1c), hepatic (alanine aminotransferase [ALT]), and cardiovascular (HDL, triglyceride [TG]/HDL ratio) efficacy parameters were assessed (P values presented for LS mean change). RESULTS: Mean ± SD HbA1c levels reduced from 8.5 ± 0.7% (69.1 ± 7.1 mmol/mol) at baseline (N = 34) to 7.5 ± 0.8% (58.9 ± 8.8 mmol/mol) at 6 months (P < 0.001); and this reduction was sustained through 24 months post-DMR (7.5 ± 1.1% [59.0 ± 12.3 mmol/mol], P < 0.001) while in greater than 50% of patients, glucose-lowering therapy was reduced or unchanged. ALT decreased from 38.1 ± 21.1 U/L at baseline to 32.5 ± 22.1 U/L at 24 months (P = 0.048). HDL and TG/HDL improved during 24-months of follow-up. No device- or procedure-related serious adverse events, unanticipated device effects, or hypoglycemic events were noted between 12 and 24 months post-DMR. CONCLUSIONS: DMR is associated with durable improvements in insulin sensitivity and multiple downstream metabolic parameters through 24 months post-treatment in type 2 diabetes. Clinical trial reg. no. NCT02413567, clinicaltrials.gov.


Assuntos
Diabetes Mellitus Tipo 2 , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/cirurgia , Duodeno/química , Duodeno/metabolismo , Duodeno/cirurgia , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento
2.
BMC Musculoskelet Disord ; 22(1): 790, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521384

RESUMO

BACKGROUND: The relevance of local twitch response (LTR) during dry needling technique (DNT) is controversial, and it is questioned whether LTR is necessary for successful outcomes. Furthermore, because the LTR during the deep DNT may be evoked with different intensities, it is unknown whether the magnitude of LTR intensity is associated with optimal clinical results, especially concerning to the effects of joint maximal range of motion (ROM). This study aimed to (i) determine whether visual inspections can quantify the LTR intensity during the DNT through a qualitative ultrasonography scale of LTR intensity (US-LTR scale), and (ii) assess the differences of US-LTR scale associated with changes in the maximal joint ROM. METHODS: Using a cross-sectional design, seven asymptomatic individuals were treated with DNT in the latent myofascial trigger point in both medial gastrocnemius muscles. During DNT, three consecutive LTRs were collected. The US-LTR scale was used to classify the LTRs into strong, medium, and weak intensities. The categories of US-LTR were differentiated by the velocity of LTRs using the optical flow algorithm. ROM changes in ankle dorsiflexion and knee extension were assessed before and immediately after DNT. RESULTS: The US-LTR scale showed the third LTR was significantly smaller than the first one (p < 0.05). A significant difference in velocity was observed between US-LTR categories (p < 0.001). A significant difference in the ROM was observed between the strong and weak-medium intensity (p < 0.05). CONCLUSIONS: The present findings suggest that the LTR intensity can be assessed using a qualitative US-LTR scale, and the effects of DNT on joint maximal ROM is maximized with higher LTR intensity. This study reports a novel qualitative method for LTR analysis with potential applications in research and clinical settings. However, further research is needed to achieve a broader application.


Assuntos
Agulhamento Seco , Síndromes da Dor Miofascial , Estudos Transversais , Humanos , Amplitude de Movimento Articular , Pontos-Gatilho , Ultrassonografia
3.
J Spinal Cord Med ; 43(3): 414-418, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-30346254

RESUMO

Context: Spasticity in neurological disorders (i.e. stroke patients and cerebral palsy) is positively improved by dry needling. However, reports are scarce regarding the potential effects of dry needling in reducing spasticity and improving functionality in patients with an incomplete spinal cord injury. The aim of this case report was to study the immediate, short-term effects of dry needling treatment (10 weeks) on spasticity, dynamic stability, walking velocity, self-independence, and pain in a single patient with an incomplete spinal cord injury.Findings: The dry needling treatment resulted in immediate, short-time effects on basal spasticity in the upper (reduction from 2 to 0 point median) and lower (reduction from 2 to 0 point median) limbs, as measured by the modified Ashworth Scale. Dynamic-stability, assessed by trunk accelerometry, improved more than 50% (Root Mean Squared of acceleration, Root Mean Squared of Jerk and step variability), and gait speed improved by 24.7 s (i.e. time to walk 20 m). Self-independence and pain were respectively scored by the Spinal Cord Independence Measure (21 points improvement) and visual analog scale (4 points improvement).Conclusions: This case report demonstrates that dry needling treatment can have positive effects on spasticity, dynamic stability, walking velocity, self-independence, and pain in patients with incomplete spinal cord injury. Further research is needed in a larger patient population to deeply understand the mechanism(s) associated with the obtained results and regarding the clinical significances of dry needling treatment for incomplete spinal cord injury.


Assuntos
Agulhamento Seco , Estado Funcional , Transtornos Neurológicos da Marcha/reabilitação , Espasticidade Muscular/reabilitação , Dor/reabilitação , Traumatismos da Medula Espinal/reabilitação , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Dor/etiologia , Traumatismos da Medula Espinal/complicações
4.
Diabetes Care ; 39(12): 2254-2261, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27519448

RESUMO

OBJECTIVE: To assess procedural safety and glycemic indices at 6 months in a first-in-human study of duodenal mucosal resurfacing (DMR), a novel, minimally invasive, upper endoscopic procedure involving hydrothermal ablation of the duodenal mucosa, in patients with type 2 diabetes and HbA1c ≥7.5% (58 mmol/mol) on one or more oral antidiabetic agents. RESEARCH DESIGN AND METHODS: Using novel balloon catheters, DMR was conducted on varying lengths of duodenum in anesthetized patients at a single medical center. RESULTS: A total of 39 patients with type 2 diabetes (screening HbA1c 9.5% [80 mmol/mol]; BMI 31 kg/m2) were treated and included in the interim efficacy analysis: 28 had a long duodenal segment ablated (LS; ∼9.3 cm treated) and 11 had a short segment ablated (SS; ∼3.4 cm treated). Overall, DMR was well tolerated with minimal gastrointestinal symptoms postprocedure. Three patients experienced duodenal stenosis treated successfully by balloon dilation. HbA1c was reduced by 1.2% at 6 months in the full cohort (P < 0.001). More potent glycemic effects were observed among the LS cohort, who experienced a 2.5% reduction in mean HbA1c at 3 months postprocedure vs. 1.2% in the SS group (P < 0.05) and a 1.4% reduction at 6 months vs. 0.7% in the SS group (P = 0.3). This occurred despite net medication reductions in the LS cohort between 0 and 6 months. Among LS patients with a screening HbA1c of 7.5-10% (58-86 mmol/mol) and on stable antidiabetic medications postprocedure, HbA1c was reduced by 1.8% at 6 months (P < 0.01). CONCLUSIONS: Single-procedure DMR elicits a clinically significant improvement in hyperglycemia in patients with type 2 diabetes in the short-term, with acceptable safety and tolerability. Long-term safety, efficacy, and durability and possible mechanisms of action require further investigation.


Assuntos
Cirurgia Bariátrica/métodos , Diabetes Mellitus Tipo 2/cirurgia , Duodeno/cirurgia , Endoscopia Gastrointestinal/métodos , Adulto , Idoso , Glicemia/metabolismo , Terapia Combinada , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/cirurgia , Hipoglicemiantes/uso terapêutico , Mucosa Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto
5.
Nutr Hosp ; 33(2): 104, 2016 Mar 25.
Artigo em Espanhol | MEDLINE | ID: mdl-27238786

RESUMO

Introducción: existe una alta prevalencia de sedentarismo, sobrepeso y obesidad en jóvenes universitarios. Objetivo: el propósito del estudio fue determinar los efectos de un programa de entrenamiento intervalado de alta intensidad (HIIT) sobre el perfil antropométrico, glicemia basal y VO 2 máx (consumo máximo de oxígeno) de jóvenes sedentarios con malnutrición por exceso. Material y métodos: 6 mujeres y 2 hombres (2 obesos y 6 con sobrepeso) se sometieron a un programa de entrenamiento de alta intensidad de 8 semanas de duración (3 sesiones/semana). Se evaluó en ayuno y posterior a 72 horas de la última intervención; peso, índice de masa corporal (IMC), contorno de cintura (CC), perímetro de cadera y glicemia de basal. El VO 2 máx fue evaluado en condiciones normales previo a la primera sesión. Resultados: las variables de estudio no presentaron cambios significativos (p > 0,05), pero reportaron disminuciones porcentuales. El peso disminuyó un 0,18%, el IMC un 0,27%, el CC 2,67%, el perímetro de cadera un 1,15%, y el VO 2 máx un 0,48%. La glicemia basal presentó la mayor disminución, pasó de 95,13 ± 23,91 a 89,88 ± 12,45 mg/dl (5,52%), estabilizando y mejorando sus niveles en cada uno de los participantes. Conclusiones: el programa de entrenamiento intervalado de alta intensidad fue factible de realizar sin resultados adversos para la salud de los participantes, la glicemia basal mostró la mayor variación, estabilizando sus valores en los participantes, lo que es un indicador positivo dentro del programa. Es necesario seguir investigando sobre esta metodología HIIT y aumentar los tiempos de estudio para ver los cambios que se pueden producir en distintos parámetros metabólicos, antropométricos y físicos en población con malnutrición por exceso.


Assuntos
Limiar Anaeróbio , Glicemia/metabolismo , Terapia por Exercício/métodos , Obesidade/terapia , Sobrepeso/terapia , Comportamento Sedentário , Antropometria , Índice de Massa Corporal , Feminino , Humanos , Masculino , Estado Nutricional , Obesidade/sangue , Sobrepeso/sangue , Educação Física e Treinamento , Estudantes , Adulto Jovem
7.
PLoS One ; 9(12): e114786, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551223

RESUMO

The natural history of introduced species is often unclear due to a lack of historical records. Even when historical information is readily available, important factors of the invasions such as genetic bottlenecks, hybridization, historical relationships among populations and adaptive changes are left unknown. In this study, we developed a set of nuclear, simple sequence repeat markers and used these to characterize the genetic diversity and population structure among native (Eurasian) and non-native (North and South American) populations of Centaurea solstitialis L., (yellow starthistle). We used these data to test hypotheses about the invasion pathways of the species that were based on historical and geographical records, and we make inferences about historical relationships among populations and demographic processes following invasion. We confirm that the center of diversity and the native range of the species is likely the eastern Mediterranean region in the vicinity of Turkey. From this region, the species likely proceeded to colonize other parts of Europe and Asia via a slow, stepwise range expansion. Spanish populations were the primary source of seed to invade South America via human-mediated events, as was evident from historical records, but populations from the eastern Mediterranean region were also important. North American populations were largely derived from South America, but had secondary contributors. We suggest that the introduction history of non-native populations from disparate parts of the native range have allowed not just one, but multiple opportunities first in South America then again in North America for the creation of novel genotypes via intraspecific hybridization. We propose that multiple intraspecific hybridization events may have created especially potent conditions for the selection of a noxious invader, and may explain differences in genetic patterns among North and South America populations, inferred differences in demographic processes, as well as morphological differences previously reported from common garden experiments.


Assuntos
Centaurea/genética , Centaurea/fisiologia , Variação Genética , Espécies Introduzidas , Dispersão Vegetal , Plantas Daninhas/genética , Plantas Daninhas/fisiologia , Bases de Dados Genéticas , Etiquetas de Sequências Expressas/metabolismo , Frequência do Gene , Loci Gênicos/genética , Repetições de Microssatélites/genética
8.
Ann Surg ; 255(6): 1080-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22534421

RESUMO

OBJECTIVE: To evaluate safety, weight loss, and cardiometabolic changes in obese subjects implanted with the duodenal-jejunal bypass liner (DJBL) for 1 year. BACKGROUND: The DJBL is an endoscopic implant that mimics the duodenal-jejunal bypass component of the Roux-en-Y gastric bypass. Previous reports have shown significant weight loss and improvement in type 2 diabetes for up to 6 months. METHODS: Morbidly obese subjects were enrolled in a single arm, open label, prospective trial and implanted with the DJBL. Primary endpoints included safety and weight change from baseline to week 52. Secondary endpoints included changes in waist circumference, blood pressure, lipids, glycemic control, and metabolic syndrome. RESULTS: The DJBL was implanted endoscopically in 39 of 42 subjects (age: 36 ± 10 years; 80% female; weight: 109 ± 18 kg; BMI: 43.7 ± 5.9 kg/m); 24 completed 52 weeks of follow-up. Three subjects could not be implanted due to short duodenal bulb. Implantation time was 24 ± 2 minutes. There were no procedure-related complications and there were 15 early endoscopic removals. In the 52-week completer population, total body weight change from baseline was -22.1 ± 2.1 kg (P < 0.0001) corresponding to 19.9 ± 1.8% of total body weight and 47.0 ± 4.4% excess of weight loss. There were also significant improvements in waist circumference, blood pressure, total and low-density lipoprotein cholesterol, triglycerides, and fasting glucose. CONCLUSIONS: The DJBL is safe when implanted for 1 year, and results in significant weight loss and improvements in cardiometabolic risk factors. These results suggest that this device may be suitable for the treatment of morbid obesity and its related comorbidities. This study was registered at www.clinicaltrials.gov (NCT00985491).


Assuntos
Cirurgia Bariátrica/instrumentação , Doenças Metabólicas/cirurgia , Obesidade Mórbida/cirurgia , Próteses e Implantes , Redução de Peso , Adulto , Diabetes Mellitus Tipo 2/cirurgia , Duodeno/cirurgia , Feminino , Cardiopatias/fisiopatologia , Cardiopatias/cirurgia , Humanos , Jejuno/cirurgia , Masculino , Doenças Metabólicas/fisiopatologia , Pessoa de Meia-Idade , Obesidade Mórbida/metabolismo , Obesidade Mórbida/fisiopatologia , Estudos Prospectivos , Implantação de Prótese
10.
Int J Surg Case Rep ; 2(7): 228-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22096735

RESUMO

INTRODUCTION: There is a high incidence of gallstones in the Chilean population. PRESENTATION OF CASE: We report on a 57-year-old man who complained of abdominal pain in the right upper quadrant. Abdominal ultrasound indicated acute cholecystitis and a single, extremely large pear-shaped gallstone (16.8 cm long, and 7.8 cm at its widest point and 4.1 cm at its narrowest point). Its fresh weight (at operation) was 278.0 g and, after 4 years, its dry weight was 259.5 g. Emergency classical cholecystectomy was carried out successfully. DISCUSSION AND CONCLUSION: We have been unable to find a report of a larger gallstone in the English or Spanish language medical literature.

11.
PLoS One ; 6(5): e20117, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21629781

RESUMO

BACKGROUND: Biological invasions are fundamentally biogeographic processes that occur over large spatial scales. Interactions with soil microbes can have strong impacts on plant invasions, but how these interactions vary among areas where introduced species are highly invasive vs. naturalized is still unknown. In this study, we examined biogeographic variation in plant-soil microbe interactions of a globally invasive weed, Centaurea solstitialis (yellow starthistle). We addressed the following questions (1) Is Centaurea released from natural enemy pressure from soil microbes in introduced regions? and (2) Is variation in plant-soil feedbacks associated with variation in Centaurea's invasive success? METHODOLOGY/PRINCIPAL FINDINGS: We conducted greenhouse experiments using soils and seeds collected from native Eurasian populations and introduced populations spanning North and South America where Centaurea is highly invasive and noninvasive. Soil microbes had pervasive negative effects in all regions, although the magnitude of their effect varied among regions. These patterns were not unequivocally congruent with the enemy release hypothesis. Surprisingly, we also found that Centaurea generated strong negative feedbacks in regions where it is the most invasive, while it generated neutral plant-soil feedbacks where it is noninvasive. CONCLUSIONS/SIGNIFICANCE: Recent studies have found reduced below-ground enemy attack and more positive plant-soil feedbacks in range-expanding plant populations, but we found increased negative effects of soil microbes in range-expanding Centaurea populations. While such negative feedbacks may limit the long-term persistence of invasive plants, such feedbacks may also contribute to the success of invasions, either by having disproportionately negative impacts on competing species, or by yielding relatively better growth in uncolonized areas that would encourage lateral spread. Enemy release from soil-borne pathogens is not sufficient to explain the success of this weed in such different regions. The biogeographic variation in soil-microbe effects indicates that different mechanisms may operate on this species in different regions, thus establishing geographic mosaics of species interactions that contribute to variation in invasion success.


Assuntos
Centaurea/crescimento & desenvolvimento , Solo , Monitoramento Ambiental , América do Norte , Plantas Daninhas/crescimento & desenvolvimento , América do Sul
12.
Mol Pharmacol ; 79(3): 596-607, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21173039

RESUMO

Organic anion-transporting polypeptides (OATPs) are involved in the liver uptake of many endogenous and xenobiotic compounds, such as bile acids and drugs, respectively. Using Xenopus laevis oocytes and Chinese hamster ovary (CHO) cells expressing rat Oatp1a1, human OATP1B1, or OATP1B3, the sensitivity of these transporters to extracellular/intracellular pH (pHo/pHi) and changes in plasma membrane potential (ΔΨ) was investigated. In X. laevis oocytes, nonspecific plasma membrane permeability increased only at pHo below 4.5. Above this value, both using oocytes and CHO cells, extracellular acidification affected differently the specific transport of taurocholic acid (TCA) and estradiol 17ß-d-glucuronide (E(2)17ßG) by Oatp1a1 (stimulation), OATP1B1 (inhibition), and OATP1B3 (stimulation). Changes in substrate uptake in the presence of valinomycin (K(+)-ionophore), carbonyl cyanide 3-chlorophenylhydrazone and nigericin (protonophores), and amiloride (Na(+)/H(+)-inhibitor) and cation replacement in the medium were studied with fluorescent probes for measuring substrate uptake (cholylglycyl amidofluorescein) and changes in pHi (SNARF-4F) and ΔΨ [DilC(1)(5)]. The results suggest that activity of these three carriers is sodium/potassium-independent and affected differently by changes in pHo and ΔΨ: Oatp1a1 was confirmed to be an electroneutral anion exchanger, whereas the function of both OATP1B1 and OATP1B3 was markedly affected by the magnitude of ΔΨ. Moreover, electrophysiological measurements revealed the existence of a net anion influx associated to OATP1B1/OATP1B3-mediated transport of TCA, E(2)17ßG, and estrone-3-sulfate. Furthermore, a leakage of Na(+) through OATP1B1 and OATP1B3, which is not coupled to substrate transport, was found. In conclusion, these results suggest that OATP1B1 and OATP1B3 are electrogenic transporters whose activity may be strongly affected under circumstances of displacement of local pH.


Assuntos
Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Animais , Células CHO , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/fisiologia , Cricetinae , Cricetulus , Estradiol/análogos & derivados , Estradiol/metabolismo , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Hidrazonas/farmacologia , Concentração de Íons de Hidrogênio , Transportador 1 de Ânion Orgânico Específico do Fígado , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Nigericina/farmacologia , Oócitos/metabolismo , Transportadores de Ânions Orgânicos/efeitos dos fármacos , Transportadores de Ânions Orgânicos/fisiologia , Transportadores de Ânions Orgânicos Sódio-Independentes/efeitos dos fármacos , Transportadores de Ânions Orgânicos Sódio-Independentes/fisiologia , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto , Ácido Taurocólico/metabolismo , Valinomicina/farmacologia , Xenopus laevis
13.
J Biol Chem ; 285(22): 16504-12, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20177056

RESUMO

Sulfated progesterone metabolite (P4-S) levels are raised in normal pregnancy and elevated further in intrahepatic cholestasis of pregnancy (ICP), a bile acid-liver disorder of pregnancy. ICP can be complicated by preterm labor and intrauterine death. The impact of P4-S on bile acid uptake was studied using two experimental models of hepatic uptake of bile acids, namely cultured primary human hepatocytes (PHH) and Na(+)-taurocholate co-transporting polypeptide (NTCP)-expressing Xenopus laevis oocytes. Two P4-S compounds, allopregnanolone-sulfate (PM4-S) and epiallopregnanolone-sulfate (PM5-S), reduced [(3)H]taurocholate (TC) uptake in a dose-dependent manner in PHH, with both Na(+)-dependent and -independent bile acid uptake systems significantly inhibited. PM5-S-mediated inhibition of TC uptake could be reversed by increasing the TC concentration against a fixed PM5-S dose indicating competitive inhibition. Experiments using NTCP-expressing Xenopus oocytes confirmed that PM4-S/PM5-S are capable of competitively inhibiting NTCP-mediated uptake of [(3)H]TC. Total serum PM4-S + PM5-S levels were measured in non-pregnant and third trimester pregnant women using liquid chromatography-electrospray tandem mass spectrometry and were increased in pregnant women, at levels capable of inhibiting TC uptake. In conclusion, pregnancy levels of P4-S can inhibit Na(+)-dependent and -independent influx of taurocholate in PHH and cause competitive inhibition of NTCP-mediated uptake of taurocholate in Xenopus oocytes.


Assuntos
Cobalto/química , Progesterona/química , Sódio/farmacologia , Ácido Taurocólico/química , Animais , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Ligação Competitiva , Linhagem Celular Tumoral , Colestase , Relação Dose-Resposta a Droga , Feminino , Hepatócitos/metabolismo , Humanos , Modelos Biológicos , Oócitos/metabolismo , Peptídeos/química , Gravidez , Sódio/química , Esteroides/metabolismo , Xenopus laevis
14.
J Biol Chem ; 281(41): 30326-35, 2006 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-16877380

RESUMO

In cholestasis, the accumulation of organic anions in hepatocytes is reduced by transporters (multidrug resistance-associated proteins and OSTalpha-OSTbeta) able to extrude them across the basolateral membrane. Here we investigated whether organic anion-transporting polypeptides (OATPs) may contribute to this function. Xenopus laevis oocytes expressing human carboxylesterase-1 efficiently loaded cholic acid (CA) methyl ester, which was cleaved to CA and exported. Expression of OATP8/1B3 enhanced CA efflux, which was trans-activated by taurocholate but trans-inhibited by reduced (GSH) and oxidized (GSSG) glutathione. Moreover, taurocholate and estradiol 17beta-D-glucuronide, but not bicarbonate and glutamate, cis-inhibited OATP8/1B3-mediated bile acid transport, whereas glutathione cis-stimulated this process, which involved the transport of glutathione itself with a stoichiometry of 2:1 (GSH/bile acid). No cis-activation by glutathione of OATP-C/1B1 was found. Using real time quantitative reverse transcription-PCR, the absolute abundance of OATP-A/1A2, OATP-C/1B1, and OATP8/1B3 mRNA in human liver biopsies was measured. In healthy liver, expression levels of OATP-C/1B1 were approximately 5-fold those of OATP8/1B3 and >100-fold those of OATP-A/1A2. This situation was not substantially modified in several cholestatic liver diseases studied here. In conclusion, although both OATP-C/1B1 and OATP8/1B3 are highly expressed, and able to transport bile acids, their mechanisms of action are different. OATP-C/1B1 may be involved in uptake processes, whereas OATP8/1B3 may mediate the extrusion of organic anions by symporting with glutathione as a normal route of exporting metabolites produced by hepatocytes or preventing their intracellular accumulation when their vectorial traffic toward the bile is impaired.


Assuntos
Ácidos e Sais Biliares/metabolismo , Glutationa/metabolismo , Hepatócitos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/fisiologia , Animais , Transporte Biológico , Hidrolases de Éster Carboxílico/biossíntese , Colatos/metabolismo , Estradiol/análogos & derivados , Estradiol/química , Humanos , Oócitos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto , Ácido Taurocólico/farmacologia , Xenopus laevis
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