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1.
Br J Clin Pharmacol ; 88(2): 846-852, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34265100

RESUMO

This analysis aimed to describe the pharmacokinetics (PK) of acalabrutinib and its active metabolite, ACP-5862. A total of 8935 acalabrutinib samples from 712 subjects and 2394 ACP-5862 samples from 304 subjects from 12 clinical studies in patients with B-cell malignancies and healthy subjects were analysed by nonlinear mixed-effects modelling. Acalabrutinib PK was characterized by a 2-compartment model with first-order elimination. The large variability in absorption was adequately described by transit compartment chain and first-order absorption, with between-occasion variability on the mean transit time and relative bioavailability. The PK of ACP-5862 was characterized by a 2-compartment model with first-order elimination, and the formation rate was defined as the acalabrutinib clearance multiplied by the fraction metabolized. Health status, Eastern Cooperative Oncology Group performance status, and coadministration of proton-pump inhibitors were significant covariates. However, none of the investigated covariates led to clinically meaningful changes in exposure, supporting a flat dosing of acalabrutinib.


Assuntos
Benzamidas , Neoplasias , Benzamidas/farmacocinética , Voluntários Saudáveis , Humanos , Modelos Biológicos , Pirazinas/farmacocinética
2.
Br J Clin Pharmacol ; 88(5): 2284-2296, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34532877

RESUMO

AIMS: Examine relationships between the systemic exposure of acalabrutinib, a highly selective, next-generation Bruton tyrosine kinase inhibitor, and its active metabolite (ACP-5862) vs. efficacy and safety responses in patients with B-cell malignancies who received acalabrutinib as monotherapy or in combination with obinutuzumab. METHODS: For exposure-efficacy analyses, patients with untreated chronic lymphocytic leukaemia were assessed for best overall response, progression-free survival and tumour regression. For exposure-safety analyses, incidences of grade ≥2 adverse events (AEs), grade ≥3 AEs and grade ≥2 events of clinical interest were assessed in patients with B-cell malignancies. Acalabrutinib and ACP-5862 pharmacokinetic (PK) parameter estimates were obtained from population PK modelling. Exposure calculations were based on study dosing regimens. Total active moieties were calculated to account for contributions of ACP-5862 to overall efficacy/safety. RESULTS: A total of 573 patients were included (exposure-efficacy analyses, n = 274; exposure-safety analyses, n = 573). Most patients (93%) received acalabrutinib 100 mg twice daily. Median total active area under the concentration-time curve (AUC24h,ss ) and total active maximal concentration at steady-state (Cmax,ss ) were similar for patients who received acalabrutinib as monotherapy or in combination with obinutuzumab, and for responders and nonresponders. No relationship was observed between AUC24h,ss /Cmax,ss and progression-free survival or tumour regression. Acalabrutinib AUC24h,ss and Cmax,ss were generally comparable across groups regardless of AE incidence. CONCLUSION: No clinically meaningful correlations between acalabrutinib PK exposure and efficacy and safety outcomes were observed. These data support the fixed acalabrutinib dose of 100 mg twice daily in the treatment of patients with B-cell malignancies.


Assuntos
Leucemia Linfocítica Crônica de Células B , Benzamidas/efeitos adversos , Benzamidas/farmacocinética , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/uso terapêutico , Pirazinas
3.
Development ; 145(1)2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29180572

RESUMO

Asna1, also known as TRC40, is implicated in the delivery of tail-anchored (TA) proteins into the endoplasmic reticulum (ER), in vesicle-mediated transport, and in chaperoning unfolded proteins during oxidative stress/ATP depletion. Here, we show that Asna1 inactivation in pancreatic progenitor cells leads to redistribution of the Golgi TA SNARE proteins syntaxin 5 and syntaxin 6, Golgi fragmentation, and accumulation of cytosolic p62+ puncta. Asna1-/- multipotent progenitor cells (MPCs) selectively activate integrated stress response signaling and undergo apoptosis, thereby disrupting endocrine and acinar cell differentiation, resulting in pancreatic agenesis. Rescue experiments implicate the Asna1 ATPase activity and a CXXC di-cysteine motif in ensuring Golgi integrity, syntaxin 5 localization and MPC survival. Ex vivo inhibition of retrograde transport reproduces the perturbed Golgi morphology, and syntaxin 5 and syntaxin 6 expression, whereas modulation of p53 activity, using PFT-α and Nutlin-3, prevents or reproduces apoptosis in Asna1-deficient and wild-type MPCs, respectively. These findings support a role for the Asna1 ATPase activity in ensuring the survival of pancreatic MPCs, possibly by counteracting p53-mediated apoptosis.


Assuntos
ATPases Transportadoras de Arsenito/metabolismo , Células-Tronco Multipotentes/metabolismo , Pâncreas/embriologia , Animais , Apoptose/genética , ATPases Transportadoras de Arsenito/genética , Sobrevivência Celular/fisiologia , Complexo de Golgi/genética , Complexo de Golgi/metabolismo , Camundongos , Camundongos Knockout , Células-Tronco Multipotentes/citologia , Pâncreas/citologia , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Ther Drug Monit ; 41(2): 235-242, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30883516

RESUMO

BACKGROUND: Circulating infliximab (IFX) concentrations correlate with clinical outcomes, forming the basis of the IFX concentration monitoring in patients with Crohn's disease. This study aims to investigate and refine the exposure-response relationship by linking the disease activity markers "Crohn's disease activity index" (CDAI) and C-reactive protein (CRP) to IFX exposure. In addition, we aim to explore the correlations between different disease markers and exposure metrics. METHODS: Data from 47 Crohn's disease patients of a randomized controlled trial were analyzed post hoc. All patients had secondary treatment failure at inclusion and had received intensified IFX of 5 mg/kg every 4 weeks for up to 20 weeks. Graphical analyses were performed to explore exposure-response relationships. Metrics of exposure included area under the concentration-time curve (AUC) and trough concentrations (Cmin). Disease activity was measured by CDAI and CRP values, their change from baseline/last visit, and response/remission outcomes at week 12. RESULTS: Although trends toward lower Cmin and lower AUC in nonresponders were observed, neither CDAI nor CRP showed consistent trends of lower disease activity with higher IFX exposure across the 30 evaluated relationships. As can be expected, Cmin and AUC were strongly correlated with each other. Contrarily, the disease activity markers were only weakly correlated with each other. CONCLUSIONS: No significant relationship between disease activity, as evaluated by CDAI or CRP, and IFX exposure was identified. AUC did not add benefit compared with Cmin. These findings support the continued use of Cmin and call for stringent objective disease activity (bio-)markers (eg, endoscopy) to form the basis of personalized IFX therapy for Crohn's disease patients with IFX treatment failure.


Assuntos
Proteína C-Reativa/metabolismo , Doença de Crohn/tratamento farmacológico , Infliximab/sangue , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Doença de Crohn/sangue , Feminino , Humanos , Infliximab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
5.
J Allergy Clin Immunol ; 142(2): 470-484.e12, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29288079

RESUMO

BACKGROUND: Metabolites of eicosapentaenoic acid exert various physiologic actions. 17,18-Epoxyeicosatetraenoic acid (17,18-EpETE) is a recently identified new class of antiallergic and anti-inflammatory lipid metabolite of eicosapentaenoic acid, but its effects on skin inflammation and the underlying mechanisms remain to be investigated. OBJECTIVE: We evaluated the effectiveness of 17,18-EpETE for control of contact hypersensitivity in mice and cynomolgus macaques. We further sought to reveal underlying mechanisms by identifying the responsible receptor and cellular target of 17,18-EpETE. METHODS: Contact hypersensitivity was induced by topical application of 2,4-dinitrofluorobenzene. Skin inflammation and immune cell populations were analyzed by using flow cytometric, immunohistologic, and quantitative RT-PCR analyses. Neutrophil mobility was examined by means of imaging analysis in vivo and neutrophil culture in vitro. The receptor for 17,18-EpETE was identified by using the TGF-α shedding assay, and the receptor's involvement in the anti-inflammatory effects of 17,18-EpETE was examined by using KO mice and specific inhibitor treatment. RESULTS: We found that preventive or therapeutic treatment with 17,18-EpETE ameliorated contact hypersensitivity by inhibiting neutrophil mobility in mice and cynomolgus macaques. 17,18-EpETE was recognized by G protein-coupled receptor (GPR) 40 (also known as free fatty acid receptor 1) and inhibited chemoattractant-induced Rac activation and pseudopod formation in neutrophils. Indeed, the antiallergic inflammatory effect of 17,18-EpETE was abolished in the absence or inhibition of GPR40. CONCLUSION: 17,18-EpETE inhibits neutrophil mobility through GPR40 activation, which is a potential therapeutic target to control allergic inflammatory diseases.


Assuntos
Antialérgicos/uso terapêutico , Anti-Inflamatórios/metabolismo , Ácidos Araquidônicos/metabolismo , Dermatite de Contato/tratamento farmacológico , Neutrófilos/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Animais , Antialérgicos/farmacologia , Ácidos Araquidônicos/farmacologia , Ácidos Araquidônicos/uso terapêutico , Movimento Celular , Células Cultivadas , Feminino , Macaca fascicularis , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pseudópodes/patologia , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais , Proteínas rac de Ligação ao GTP/metabolismo
6.
Diabetologia ; 59(5): 1007-11, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26847769

RESUMO

AIMS/HYPOTHESIS: In vivo imaging of the developing pancreas is challenging due to the inaccessibility of the tissue. To circumvent this, on embryonic day 10.5 (E10.5) we transplanted a mouse developing pancreatic bud into the anterior chamber of the eye (ACE) to determine whether the eye is a useful transplant site to support pancreas development. METHODS: We transplanted an E10.5 dorsal pancreatic bud into the ACE of a syngeneic recipient mouse. Using a mouse insulin promoter-green fluorescent protein (MIP-GFP) mouse as the tissue donor, we non-invasively imaged the pancreatic bud as it develops at single beta cell resolution across time. RESULTS: The transplanted pancreatic bud rapidly engrafts and vascularises when transplanted into the ACE. The pancreatic progenitor cells differentiate into exocrine and endocrine cells, including cells expressing insulin, glucagon and somatostatin. The morphology of the transplanted pancreatic bud resembles that of the native developing pancreas. Beta cells within the transplanted pancreatic bud respond to glucose in a manner similar to that of native fetal beta cells and superior to that of in vitro developed beta cells. Unlike in vitro grown pancreatic explants, pancreatic tissue developing in the ACE is vascularised, providing the developing pancreatic tissue with a milieu resembling the native situation. CONCLUSIONS/INTERPRETATION: Altogether, we show that the ACE is able to support growth, differentiation and function of a developing pancreatic bud across time in vivo.


Assuntos
Câmara Anterior/citologia , Ilhotas Pancreáticas/embriologia , Pâncreas/embriologia , Animais , Câmara Anterior/metabolismo , Diferenciação Celular/fisiologia , Feminino , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Gravidez
7.
J Biol Chem ; 290(31): 19034-43, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26085100

RESUMO

Hepatosteatosis is associated with the development of both hepatic insulin resistance and Type 2 diabetes. Hepatic expression of Cd36, a fatty acid transporter, is enhanced in obese and diabetic murine models and human nonalcoholic fatty liver disease, and thus it correlates with hyperinsulinemia, steatosis, and insulin resistance. Here, we have explored the effect of hyperinsulinemia on hepatic Cd36 expression, development of hepatosteatosis, insulin resistance, and dysglycemia. A 3-week sucrose-enriched diet was sufficient to provoke hyperinsulinemia, hepatosteatosis, hepatic insulin resistance, and dysglycemia in CBA/J mice. The development of hepatic steatosis and insulin resistance in CBA/J mice on a sucrose-enriched diet was paralleled by increased hepatic expression of the transcription factor Pparγ and its target gene Cd36 whereas that of genes implicated in lipogenesis, fatty acid oxidation, and VLDL secretion was unaltered. Additionally, we demonstrate that insulin, in a Pparγ-dependent manner, is sufficient to directly increase Cd36 expression in perfused livers and isolated hepatocytes. Mouse strains that display low insulin levels, i.e. C57BL6/J, and/or lack hepatic Pparγ, i.e. C3H/HeN, do not develop hepatic steatosis, insulin resistance, or dysglycemia on a sucrose-enriched diet, suggesting that elevated insulin levels, via enhanced CD36 expression, provoke fatty liver development that in turn leads to hepatic insulin resistance and dysglycemia. Thus, our data provide evidence for a direct role for hyperinsulinemia in stimulating hepatic Cd36 expression and thus the development of hepatosteatosis, hepatic insulin resistance, and dysglycemia.


Assuntos
Antígenos CD36/metabolismo , Fígado Gorduroso/metabolismo , Resistência à Insulina , Fígado/metabolismo , Animais , Antígenos CD36/genética , Fígado Gorduroso/etiologia , Células Hep G2 , Humanos , Insulina/fisiologia , Masculino , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , PPAR gama/metabolismo
8.
J Alzheimers Dis ; 99(3): 1033-1046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728183

RESUMO

Background: Individuals with type 2 diabetes (T2D) have an increased risk of cognitive symptoms and Alzheimer's disease (AD). Mis-metabolism with aggregation of amyloid-ß peptides (Aß) play a key role in AD pathophysiology. Therefore, human studies on Aß metabolism and T2D are warranted. Objective: The objective of this study was to examine whether acute hyperglycemia affects plasma Aß1-40 and Aß1-42 concentrations in individuals with T2D and matched controls. Methods: Ten participants with T2D and 11 controls (median age, 69 years; range, 66-72 years) underwent hyperglycemic clamp and placebo clamp (saline infusion) in a randomized order, each lasting 4 hours. Aß1-40, Aß1-42, and insulin-degrading enzyme (IDE) plasma concentrations were measured in blood samples taken at 0 and 4 hours of each clamp. Linear mixed-effect regression models were used to evaluate the 4-hour changes in Aß1-40 and Aß1-42 concentrations, adjusting for body mass index, estimated glomerular filtration rate, and 4-hour change in insulin concentration. Results: At baseline, Aß1-40 and Aß1-42 concentrations did not differ between the two groups. During the hyperglycemic clamp, Aß decreased in the control group, compared to the placebo clamp (Aß1-40: p = 0.034, Aß1-42: p = 0.020), IDE increased (p = 0.016) during the hyperglycemic clamp, whereas no significant changes in either Aß or IDE was noted in the T2D group. Conclusions: Clamp-induced hyperglycemia was associated with increased IDE levels and enhanced Aß40 and Aß42 clearance in controls, but not in individuals with T2D. We hypothesize that insulin-degrading enzyme was inhibited during hyperglycemic conditions in people with T2D.


Assuntos
Peptídeos beta-Amiloides , Diabetes Mellitus Tipo 2 , Técnica Clamp de Glucose , Hiperglicemia , Fragmentos de Peptídeos , Humanos , Peptídeos beta-Amiloides/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/sangue , Idoso , Masculino , Hiperglicemia/sangue , Feminino , Fragmentos de Peptídeos/sangue , Glicemia/metabolismo , Insulisina/metabolismo
9.
Commun Biol ; 6(1): 877, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626210

RESUMO

Although insulin mediated glucose uptake in skeletal muscle is a major mechanism ensuring glucose disposal in humans, glucose effectiveness, i.e., the ability of glucose itself to stimulate its own uptake independent of insulin, accounts for roughly half of the glucose disposed during an oral glucose tolerance test. Both insulin dependent and insulin independent skeletal muscle glucose uptake are however reduced in individuals with diabetes. We here show that AMPK activator O304 stimulates insulin independent glucose uptake and utilization in skeletal muscle and heart in vivo, while preventing glycogen accumulation. Combined glucose uptake and utilization requires an increased metabolic demand and we show that O304 acts as a mitochondrial uncoupler, i.e., generates a metabolic demand. O304 averts gene expression changes associated with metabolic inflexibility in skeletal muscle and heart of diabetic mice and reverts diabetic cardiomyopathy. In Type 2 diabetes, insulin resistance elicits compensatory insulin hypersecretion, provoking ß-cell stress and eventually compensatory failure. In db/db mice O304 preserves ß-cell function by preventing decline in insulin secretion, ß-cell mass, and pancreatic insulin content. Thus, as a dual AMPK activator and mitochondrial uncoupler O304 mitigates two central defects of T2D; impaired glucose uptake/utilization and ß-cell failure, which today lack effective treatment.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Camundongos , Animais , Glucose , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Insulina Regular Humana , Músculo Esquelético , Insulina
10.
Cell Metab ; 5(3): 207-19, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17339028

RESUMO

Impaired glucose-stimulated insulin secretion (GSIS) and perturbed proinsulin processing are hallmarks of beta cell dysfunction in type 2 diabetes. Signals that can preserve and/or enhance beta cell function are therefore of great therapeutic interest. Here we show that bone morphogenetic protein 4 (Bmp4) and its high-affinity receptor, Bmpr1a, are expressed in beta cells. Mice with attenuated BMPR1A signaling in beta cells show decreased expression of key genes involved in insulin gene expression, proinsulin processing, glucose sensing, secretion stimulus coupling, incretin signaling, and insulin exocytosis and develop diabetes due to impaired insulin secretion. We also show that transgenic expression of Bmp4 in beta cells enhances GSIS and glucose clearance and that systemic administration of BMP4 protein to adult mice significantly stimulates GSIS and ameliorates glucose tolerance in a mouse model of glucose intolerance. Thus, BMP4-BMPR1A signaling in beta cells plays a key role in GSIS.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Animais , Comunicação Autócrina , Proteína Morfogenética Óssea 4 , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Proteínas Morfogenéticas Ósseas/administração & dosagem , Proteínas Morfogenéticas Ósseas/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Expressão Gênica , Glucose/metabolismo , Intolerância à Glucose/tratamento farmacológico , Proteínas de Homeodomínio/genética , Insulina/genética , Secreção de Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Transdução de Sinais , Transativadores/genética
11.
Int J Pharm ; 628: 122238, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36174850

RESUMO

This paper reviews many of the properties of a peptide that need to be considered prior to development as an oral dosage form when co-formulated with a permeation enhancer to improve oral bioavailability, including the importance and implications of peptide half-life on variability in pharmacokinetic profiles. Clinical considerations in terms of food and drug-drug interactions are also discussed. The paper further gives a brief overview how permeation enhancers overcome barriers that limit oral absorption of peptides and thereby improve their oral bioavailability, albeit bioavailabilities are still low single digit and variability is high.


Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos , Administração Oral , Peptídeos/química , Disponibilidade Biológica , Meia-Vida
12.
Commun Biol ; 4(1): 1306, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795407

RESUMO

Age is associated with progressively impaired, metabolic, cardiac and vascular function, as well as reduced work/exercise capacity, mobility, and hence quality of life. Exercise exhibit positive effects on age-related dysfunctions and diseases. However, for a variety of reasons many aged individuals are unable to engage in regular physical activity, making the development of pharmacological treatments that mimics the beneficial effects of exercise highly desirable. Here we show that the pan-AMPK activator O304, which is well tolerated in humans, prevented and reverted age-associated hyperinsulinemia and insulin resistance, and improved cardiac function and exercise capacity in aged mice. These results provide preclinical evidence that O304 mimics the beneficial effects of exercise. Thus, as an exercise mimetic in clinical development, AMPK activator O304 holds great potential to mitigate metabolic dysfunction, and to improve cardiac function and exercise capacity, and hence quality of life in aged individuals.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Tolerância ao Exercício/genética , Coração/fisiologia , Resistência à Insulina/genética , Camundongos/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Fatores Etários , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos/genética , Camundongos/metabolismo , Condicionamento Físico Animal
13.
Sci Rep ; 11(1): 24410, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34949756

RESUMO

AMP-activated protein kinase (AMPK) has an important role in cellular energy homeostasis and has emerged as a promising target for treatment of Type 2 Diabetes (T2D) due to its beneficial effects on insulin sensitivity and glucose homeostasis. O304 is a pan-AMPK activator that has been shown to improve glucose homeostasis in both mouse models of diabetes and in human T2D subjects. Here, we describe the genome-wide transcriptional profile and chromatin landscape of pancreatic islets following O304 treatment of mice fed high-fat diet (HFD). O304 largely prevented genome-wide gene expression changes associated with HFD feeding in CBA mice and these changes were associated with remodelling of active and repressive chromatin marks. In particular, the increased expression of the ß-cell stress marker Aldh1a3 in islets from HFD-mice is completely abrogated following O304 treatment, which is accompanied by loss of active chromatin marks in the promoter as well as distant non-coding regions upstream of the Aldh1a3 gene. Moreover, O304 treatment restored dysfunctional glucose homeostasis as well as expression of key markers associated with ß-cell function in mice with already established obesity. Our findings provide preclinical evidence that O304 is a promising therapeutic compound not only for T2D remission but also for restoration of ß-cell function following remission of T2D diabetes.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ativadores de Enzimas/farmacologia , Expressão Gênica/efeitos dos fármacos , Código das Histonas/efeitos dos fármacos , Código das Histonas/genética , Histonas/metabolismo , Ilhotas Pancreáticas/metabolismo , Obesidade/metabolismo , Tiadiazóis/farmacologia , Proteínas Quinases Ativadas por AMP/fisiologia , Família Aldeído Desidrogenase 1/genética , Família Aldeído Desidrogenase 1/metabolismo , Animais , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Células Secretoras de Insulina/fisiologia , Camundongos , Camundongos Endogâmicos CBA , Obesidade/etiologia , Retinal Desidrogenase/genética , Retinal Desidrogenase/metabolismo
14.
Cell Metab ; 1(4): 245-58, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16054069

RESUMO

Obesity is typically associated with elevated levels of free fatty acids (FFAs) and is linked to glucose intolerance and type 2 diabetes. FFAs exert divergent effects on insulin secretion from beta cells: acute exposure to FFAs stimulates insulin secretion, whereas chronic exposure impairs insulin secretion. The G protein-coupled receptor GPR40 is selectively expressed in beta cells and is activated by FFAs. We show here that GPR40 mediates both acute and chronic effects of FFAs on insulin secretion and that GPR40 signaling is linked to impaired glucose homeostasis. GPR40-deficient beta cells secrete less insulin in response to FFAs, and loss of GPR40 protects mice from obesity-induced hyperinsulinemia, hepatic steatosis, hypertriglyceridemia, increased hepatic glucose output, hyperglycemia, and glucose intolerance. Conversely, overexpression of GPR40 in beta cells of mice leads to impaired beta cell function, hypoinsulinemia, and diabetes. These results suggest that GPR40 plays an important role in the chain of events linking obesity and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Fígado Gorduroso/metabolismo , Glucose/fisiologia , Homeostase/fisiologia , Hiperinsulinismo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Hipertrigliceridemia/genética , Hipertrigliceridemia/metabolismo , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Camundongos , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética
15.
Sci Rep ; 10(1): 20438, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33235246

RESUMO

Type 2 diabetes (T2D), alike Parkinson's disease (PD), belongs to the group of protein misfolding diseases (PMDs), which share aggregation of misfolded proteins as a hallmark. Although the major aggregating peptide in ß-cells of T2D patients is Islet Amyloid Polypeptide (IAPP), alpha-synuclein (αSyn), the aggregating peptide in substantia nigra neurons of PD patients, is expressed also in ß-cells. Here we show that αSyn, encoded by Snca, is a component of amyloid extracted from pancreas of transgenic mice overexpressing human IAPP (denoted hIAPPtg mice) and from islets of T2D individuals. Notably, αSyn dose-dependently promoted IAPP fibril formation in vitro and tail-vein injection of αSyn in hIAPPtg mice enhanced ß-cell amyloid formation in vivo whereas ß-cell amyloid formation was reduced in hIAPPtg mice on a Snca -/- background. Taken together, our findings provide evidence that αSyn and IAPP co-aggregate both in vitro and in vivo, suggesting a role for αSyn in ß-cell amyloid formation.


Assuntos
Amiloide/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , alfa-Sinucleína/genética , Animais , Diabetes Mellitus Tipo 2/genética , Modelos Animais de Doenças , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Transgênicos , Agregados Proteicos , alfa-Sinucleína/metabolismo
16.
Endocrinology ; 150(1): 87-97, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18772243

RESUMO

The homeodomain transcription factor insulin promoter factor (IPF)-1/pancreatic duodenal homeobox (PDX)-1 plays a crucial role in both pancreas development and maintenance of beta-cell function. Targeted disruption of the Ipf1/Pdx1 gene in beta-cells of mice leads to overt diabetes and reduced Ipf1/Pdx1 gene expression results in decreased insulin expression and secretion. In humans, mutations in the IPF1 gene have been linked to diabetes. Hence, the identification of molecular mechanisms regulating the transcriptional activity of this key transcription factor is of great interest. Herein we analyzed homeodomain-interacting protein kinase (Hipk) 2 expression in the embryonic and adult pancreas by in situ hybridization and RT-PCR. Moreover, we functionally characterized the role of HIPK2 in regulating IPF1/PDX1 transcriptional activity by performing transient transfection experiments and RNA interference. We show that Hipk2 is expressed in the developing pancreatic epithelium from embryonic d 12-15 but that the expression becomes preferentially confined to pancreatic endocrine cells at later developmental stages. Moreover, we show that HIPK2 positively influences IPF1/PDX1 transcriptional activity and that the kinase activity of HIPK2 is required for this effect. We also demonstrate that HIPK2 directly phosphorylates the C-terminal portion of IPF1/PDX1. Taken together, our data provide evidence for a new mechanism by which IPF1/PDX1 transcriptional activity, and thus possibly pancreas development and/or beta-cell function, is regulated.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Homeodomínio/genética , Pâncreas/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/genética , Envelhecimento , Animais , Primers do DNA , Regulação da Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/isolamento & purificação , Glutationa Transferase/metabolismo , Proteínas de Homeodomínio/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Ilhotas Pancreáticas/fisiologia , Camundongos , Proteínas Nucleares/metabolismo , Pâncreas/crescimento & desenvolvimento , Biossíntese de Proteínas , RNA/genética , RNA/isolamento & purificação , RNA Interferente Pequeno/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/metabolismo , Transcrição Gênica
17.
Gene Expr Patterns ; 9(4): 193-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19135553

RESUMO

MicroRNAs (miRNA) are small non-coding RNAs that inhibit gene expression through binding to complementary messenger RNA sequences. miRNAs have been predicted to target genes important for pancreas development, proper endocrine cell function and metabolism. We previously described that miRNA-7 (miR-7) was the most abundant and differentially expressed islet miRNA, with 200-fold higher expression in mature human islets than in acinar tissue. Here we have analyzed the temporal and spatial expression of miR-7 in human fetal pancreas from 8 to 22 weeks of gestational age (wga). Human fetal (8-22wga) and adult pancreases were processed for immunohistochemistry, in situ hybridization, and quantitative RT-PCR of miRNA and mRNA. miR-7 was expressed in the human developing pancreas from around 9wga and reached its maximum expression levels between 14 and 18wga, coinciding with the exponential increase of the pancreatic endocrine hormones. Throughout development miR-7 expression was preferentially localized to endocrine cells and its expression persisted in the adult pancreas. The present study provides a detailed analysis of the spatiotemporal expression of miR-7 in developing human pancreas. The specific localization of miR-7 expression to fetal and adult endocrine cells indicates a potential role for miR-7 in endocrine cell differentiation and/or function. Future functional studies of a potential role for miR-7 function in islet cell differentiation and physiology are likely to identify novel targets for the treatment of diabetes and will lead to the development of improved protocols for generating insulin-producing cells for cell replacement therapy.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética , Pâncreas/metabolismo , Adulto , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Feminino , Feto/citologia , Feto/metabolismo , Imunofluorescência , Idade Gestacional , Glucagon/genética , Glucagon/metabolismo , Humanos , Hibridização In Situ , Insulina/genética , Insulina/metabolismo , MicroRNAs/metabolismo , Microscopia Confocal , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Pâncreas/citologia , Pâncreas/embriologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Somatostatina/genética , Somatostatina/metabolismo
18.
J Histochem Cytochem ; 57(9): 811-24, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19365093

RESUMO

The development of efficient, reproducible protocols for directed in vitro differentiation of human embryonic stem (hES) cells into insulin-producing beta cells will benefit greatly from increased knowledge regarding the spatiotemporal expression profile of key instructive factors involved in human endocrine cell generation. Human fetal pancreases 7 to 21 weeks of gestational age, were collected following consent immediately after pregnancy termination and processed for immunostaining, in situ hybridization, and real-time RT-PCR expression analyses. Islet-like structures appear from approximately week 12 and, unlike the mixed architecture observed in adult islets, fetal islets are initially formed predominantly by aggregated insulin- or glucagon-expressing cells. The period studied (7-22 weeks) coincides with a decrease in the proliferation and an increase in the differentiation of the progenitor cells, the initiation of NGN3 expression, and the appearance of differentiated endocrine cells. The present study provides a detailed characterization of islet formation and expression profiles of key intrinsic and extrinsic factors during human pancreas development. This information is beneficial for the development of efficient protocols that will allow guided in vitro differentiation of hES cells into insulin-producing cells.


Assuntos
Células Endócrinas/citologia , Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Diferenciação Celular , Células Endócrinas/metabolismo , Feminino , Feto , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Ilhotas Pancreáticas/embriologia , Ilhotas Pancreáticas/metabolismo , Pessoa de Meia-Idade , Pâncreas/embriologia , Pâncreas/metabolismo , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Clin Pharmacokinet ; 58(5): 659-672, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30556110

RESUMO

INTRODUCTION: Bruton tyrosine kinase (BTK) is a key component of B-cell receptor signalling, critical for cell proliferation. Acalabrutinib, a selective, covalent BTK inhibitor, recently received an accelerated approval in relapsed/refractory mantle cell lymphoma. This analysis characterized the population pharmacokinetics (PK) of acalabrutinib and its metabolite ACP-5862. METHODS: Data were obtained from six phase I/II trials in adult patients with B-cell malignancy and seven phase I trials in healthy volunteers. Pooled concentration-time data, at dose levels ranging from 15 to 400 mg, were analysed using non-linear mixed-effects modelling. Base model parameters were scaled with body weight and normalized to 70 kg (fixed exponents: 0.75 and 1 for clearance and volumes, respectively). A full covariate approach was used to evaluate any relevant effects of dose, health group/disease status, hepatic and renal impairment, use of acid-reducing agents, race and sex. RESULTS: A total of 11,196 acalabrutinib and 1068 ACP-5862 concentration-time samples were available. The PK of both analytes were well described using two-compartment disposition models. Acalabrutinib absorption was characterized using sequential zero- and first-order constants and a lag time. Apparent clearance (CL/F) of acalabrutinib was 169 L/h (95% CI 159-175). Relative to the 100 mg dose group, the 15 and 400 mg dose groups showed a 1.44-fold higher and 0.77-fold lower CL/F, respectively. The clearance for ACP-5862 was 21.9 L/h (95% CI 19.5-24.0). The fraction metabolized was fixed to 0.4. The central and peripheral volumes of distribution were 33.1 L (95% CI 24.4-41.0) and 226 L (95% CI 149-305) for acalabrutinib, and 38.5 L (95% CI 31.6-49.2) and 38.4 L (95% CI 32.3-47.9) for ACP-5862. None of the investigated covariates led to clinically meaningful changes in exposure. CONCLUSION: The PK of acalabrutinib and its metabolite ACP-5862 were adequately characterized. Acalabrutinib CL/F decreased with increasing dose, but the trend was small over the 75-250 mg range. No dose adjustment was necessary for intrinsic or extrinsic covariates.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antineoplásicos/farmacocinética , Benzamidas/farmacocinética , Transtornos Linfoproliferativos/metabolismo , Modelos Biológicos , Inibidores de Proteínas Quinases/farmacocinética , Pirazinas/farmacocinética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/sangue , Benzamidas/sangue , Feminino , Voluntários Saudáveis , Humanos , Transtornos Linfoproliferativos/sangue , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/sangue , Pirazinas/sangue , Adulto Jovem
20.
JCI Insight ; 3(12)2018 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-29925691

RESUMO

AMPK activated protein kinase (AMPK), a master regulator of energy homeostasis, is activated in response to an energy shortage imposed by physical activity and caloric restriction. We here report on the identification of PAN-AMPK activator O304, which - in diet-induced obese mice - increased glucose uptake in skeletal muscle, reduced ß cell stress, and promoted ß cell rest. Accordingly, O304 reduced fasting plasma glucose levels and homeostasis model assessment of insulin resistance (HOMA-IR) in a proof-of-concept phase IIa clinical trial in type 2 diabetes (T2D) patients on Metformin. T2D is associated with devastating micro- and macrovascular complications, and O304 improved peripheral microvascular perfusion and reduced blood pressure both in animals and T2D patients. Moreover, like exercise, O304 activated AMPK in the heart, increased cardiac glucose uptake, reduced cardiac glycogen levels, and improved left ventricular stroke volume in mice, but it did not increase heart weight in mice or rats. Thus, O304 exhibits a great potential as a novel drug to treat T2D and associated cardiovascular complications.


Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Compostos Heterocíclicos/farmacologia , Homeostase , Animais , Glicemia/efeitos dos fármacos , Pressão Sanguínea , Cardiomegalia , Doenças Cardiovasculares , Glicogênio/metabolismo , Coração , Holoprosencefalia/prevenção & controle , Humanos , Resistência à Insulina , Células Secretoras de Insulina , Anormalidades Maxilomandibulares/prevenção & controle , Metformina/uso terapêutico , Camundongos , Camundongos Obesos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Ratos , Volume Sistólico
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