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1.
Artigo em Inglês | MEDLINE | ID: mdl-38664310

RESUMO

OBJECTIVE: The objective of this study was to investigate whether an obesity-related inflammatory protein signature (OIPS) is associated with adverse cardiovascular events. METHODS: The Olink Target 96 Inflammation panel was performed in 6662 participants from the population-based Gutenberg Health Study (GHS). The OIPS was selected by a logistic regression model, and its association with cardiovascular outcomes was evaluated by Cox regression analysis. The GHS-derived OIPS was externally validated in the MyoVasc study. RESULTS: The identified OIPS entailed 21 proteins involved in chemokine activity, tumor necrosis factor (TNF) receptor binding, and growth factor receptor binding. The signature revealed a novel positive association of axis inhibition protein 1 with obesity. The OIPS was associated with increased risk of all-cause and cardiac deaths, major adverse cardiovascular events, and incident coronary artery disease, independent of clinical covariates and established risk instruments. A BMI-stratified analysis confirmed the association of OIPS with increased death in those with obesity and overweight and with increased risk for coronary artery disease in those with obesity. The association of OIPS with increased risk of all-cause and cardiac deaths was validated in the MyoVasc cohort. CONCLUSIONS: The OIPS showed a significant association with adverse clinical outcomes, particularly in those with overweight and obesity, and represents a promising tool for identifying patients at higher risk for worse cardiovascular outcomes.

2.
Nat Commun ; 14(1): 7151, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932258

RESUMO

Non-alcoholic steatohepatitis (NASH) is a progressive, inflammatory liver disease with no approved pharmacological treatment. This Phase IIa, double-blind, placebo-controlled, multicentre trial (ClinicalTrials.gov: NCT03166735) investigated pharmacodynamics and safety of BI 1467335, an amine oxidase copper-containing 3 (AOC3) inhibitor, in adults with NASH from Europe and North America. Participants from 44 centres across the US, Germany, Spain, Belgium, the UK, Netherlands, Canada, France and Ireland were randomised (2:1:1:1:2; 27 July 2017 to 14 June 2019) to daily oral BI 1467335 1 mg (n = 16), 3 mg (n = 16), 6 mg (n = 17), 10 mg (n = 32) or placebo (n = 32) for 12 weeks, with follow-up to Week 16. Primary endpoint was AOC3 activity relative to baseline (%), 24 hours post-dose after 12 weeks' treatment. Secondary biomarker endpoints included changes from baseline at Week 12 in alanine aminotransferase (ALT) and caspase-cleaved cytokeratin 18 (CK-18 caspase). Mean AOC3 activities relative to baseline at Week 12: 90.4% (placebo; n = 32), 26.5% (1 mg; n = 16), 10.4% (3 mg; n = 16), 5.0% (6 mg; n = 16), 3.3% (10 mg; n = 32). These changes indicated that BI 1467335 dose-dependently inhibited AOC3 activity; ≥3 mg doses achieved >80% inhibition ( < 20% activity) at Week 4. At Week 12 following doses of BI 1467335 ≥ 3 mg, ALT and CK-18 caspase decreased dose-dependently. All tested BI 1467335 doses were well tolerated, with no clinically relevant treatment-emergent safety signals. BI 1467335 strongly inhibited AOC3 in participants with NASH, with doses ≥3 mg dose-dependently reducing the levels of liver injury biomarkers, ALT and CK-18. This trial was registered with ClinicalTrials.gov (NCT03166735) and the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT 2016-000499-83).


Assuntos
Amina Oxidase (contendo Cobre) , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Caspases , Método Duplo-Cego , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Resultado do Tratamento , Amina Oxidase (contendo Cobre)/antagonistas & inibidores
3.
Hepatol Commun ; 7(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37889522

RESUMO

BACKGROUND: Portal hypertension is a severe complication of cirrhosis. This Phase Ib study (NCT03842761) assessed the safety, tolerability, and pharmacokinetics of soluble guanylyl cyclase activator BI 685509 in patients with mild or moderate hepatic impairment (Child-Pugh [CP] A or B cirrhosis) and healthy volunteers (HVs). METHODS: In this single-center, randomized, placebo-controlled study, patients received BI 685509 (maximum doses: 1, 2, or 3 mg, twice daily [BID]) or placebo for 28 days. HVs received one 0.5 mg dose of BI 685509 or placebo. RESULTS: In total, 64 participants (CP-A, n=24; CP-B, n=25; HVs, n=15) were included; most commonly with NAFLD (36.7%), alcohol-associated (30.6%), or chronic viral hepatitis-related cirrhosis (28.6%). In patients with CP-A cirrhosis, drug-related adverse events (AEs) occurred in 5.6% of BI 685509-treated patients and 16.7% of placebo recipients. In patients with CP-B cirrhosis, drug-related AEs occurred in 26.3% of BI 685509-treated patients only. No serious AEs occurred in patients with CP-A cirrhosis; in patients with CP-B cirrhosis, serious AEs (not drug-related) occurred in 10.5% of BI 685509-treated patients and 16.7% of patients receiving placebo. BI 685509 was rapidly absorbed; exposure increased with dosage and was similar between etiologies and between patients with CP-A cirrhosis and patients with CP-A cirrhosis but lower in HVs. The mean percentage portal-systemic shunt fraction was measured in patients with CP-A cirrhosis and decreased at the end of treatment in the 2 mg BID (-11.2 ± 11.9%) and 3 mg BID (-14.0 ± 8.4%) BI 685509 dose groups, but not in the placebo group (+1.0 ± 27.3%). CONCLUSION: BI 685509 was generally well tolerated, with 3 serious, not drug-related AEs reported in patients with CP-B cirrhosis. In patients with CP-A cirrhosis, portal-systemic shunt fraction in the exploratory efficacy analysis was reduced by 2 mg BID and 3 mg BID BI 685509.


Assuntos
Cirrose Hepática , Humanos , Guanilil Ciclase Solúvel , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico
4.
J Hepatol ; 78(4): 852-865, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36526000

RESUMO

Biomarkers have the potential to accelerate drug development, as early indicators of improved clinical response, to improve patient safety, and for personalised medicine. However, few have been approved through the biomarker qualification pathways of the regulatory agencies. This paper outlines how biomarkers can accelerate drug development, and reviews the lessons learned by the EU IMI2-funded LITMUS consortium, which has had several interactions with regulatory agencies in both the US and EU regarding biomarker qualification in patients with non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. Sharing knowledge of such interactions with the scientific community is of paramount importance to increase the chances of qualification of relevant biomarkers that may accelerate drug development, and thereby help patients, across disease indications. A qualified biomarker enables a decision to be made that all understand and support in a common framework.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Biomarcadores/metabolismo , Desenvolvimento de Medicamentos
5.
Sci Rep ; 12(1): 8708, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35610268

RESUMO

Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare lung disorder involving production of autoantibodies against endogenous granulocyte-macrophage colony-stimulating factor (GM-CSF). This study aimed to identify biomarkers that could be used to monitor for aPAP, particularly in patients treated with anti-GM-CSF antibodies. This was an exploratory, prospective, observational, single-center study. Pre-specified biomarkers were evaluated between baseline and Day 120 in serum/plasma, whole blood, sputum and exhaled breath condensate from patients with aPAP, healthy volunteers, and patients with chronic obstructive pulmonary disease (COPD) and asthma (not treated with anti-GM-CSF and with no evidence of aPAP). Pulmonary function tests were also performed. Overall, 144 individuals were enrolled (aPAP: n = 34, healthy volunteers: n = 24, COPD: n = 40 and asthma: n = 46). Plasma GM-CSF levels were lower, and Krebs von den Lungen 6 and GM-CSF autoantibody ranges were higher, in patients with aPAP compared with other populations. Surfactant proteins-A and -D, lactate dehydrogenase and carcinoembryonic antigen ranges partially or completely overlapped across populations. Most plasma biomarkers showed high sensitivity and specificity for detection of aPAP; GM-CSF and GM-CSF autoantibody concentrations demonstrated equivalent sensitivity for differentiating aPAP. In addition to characteristic GM-CSF autoantibodies, assessment of plasma GM-CSF may identify individuals at risk of developing aPAP.Trial registration: EudraCT, 2012-003475-19. Registered 23 July 2012- https://eudract.ema.europa.eu/ .


Assuntos
Asma , Doenças Autoimunes , Proteinose Alveolar Pulmonar , Doença Pulmonar Obstrutiva Crônica , Asma/complicações , Asma/diagnóstico , Autoanticorpos , Biomarcadores , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Estudos Prospectivos , Proteinose Alveolar Pulmonar/diagnóstico , Doença Pulmonar Obstrutiva Crônica/complicações
6.
J Magn Reson Imaging ; 56(2): 368-379, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34953171

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is rapidly increasing worldwide. It is subdivided into nonalcoholic fatty liver (NAFL) and the more aggressive form, nonalcoholic steatohepatitis (NASH), which carries a higher risk of developing fibrosis and cirrhosis. There is currently no reliable non-invasive method for differentiating NASH from NAFL. PURPOSE: To investigate the ability of magnetic resonance imaging (MRI)-based imaging biomarkers to diagnose NASH and moderate fibrosis as well as assess their repeatability. STUDY TYPE: Prospective. SUBJECTS: Sixty-eight participants (41% women) with biopsy-proven NAFLD (53 NASH and 15 NAFL). Thirty participants underwent a second MRI in order to assess repeatability. FIELD STRENGTH/SEQUENCE: 3.0 T; MR elastography (MRE) (a spin-echo echo-planar imaging [SE-EPI] sequence with motion-encoding gradients), MR proton density fat fraction (PDFF) and R2* mapping (a multi-echo three-dimensional gradient-echo sequence), T1 mapping (a single-point saturation-recovery technique), and diffusion-weighted imaging (SE-EPI sequence). ASSESSMENT: Quantitative MRI measurements were obtained and assessed alone and in combination with biochemical markers (cytokeratin-18 [CK18] M30, alanine transaminase [ALT], and aspartate transaminase [AST]) using logistic regression models. Models that could differentiate between NASH and NAFL and between moderate to advanced fibrosis (F2-4) and no or mild fibrosis (F0-1), based on the histopathological results, were identified. STATISTICAL TESTS: Independent samples t-test, Pearson's chi-squared test, area under the receiver operating characteristic curve (AUROC), Spearman's correlation, intra-individual coefficient of variation, and intraclass correlation coefficient (ICC). Statistical significance was set at P < 0.05. RESULTS: There was a significant difference between the NASH and NAFL groups with liver stiffness assessed with MRE, CK18 M30, and ALT, with an AUROC of 0.74, 0.76, and 0.70, respectively. Both MRE and PDFF contributed significantly to a bivariate model for diagnosing NASH (AUROC = 0.84). MRE could significantly differentiate between F2-4 and F0-1 (AUROC = 0.74). A model combining MRE with AST improved the diagnosis of F2-4 (AUROC = 0.83). The ICC for repeatability was 0.94 and 0.99 for MRE and PDFF, respectively. DATA CONCLUSION: MRE can potentially diagnose NASH and differentiate between fibrosis stages. Combining MRE with PDFF improves the diagnosis of NASH. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Biomarcadores , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Prospectivos , Prótons
7.
J Clin Pharmacol ; 58(12): 1566-1577, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30113724

RESUMO

BI 655064 is a humanized antagonistic anti-cluster of differentiation (CD) 40 monoclonal antibody that selectively blocks the CD40-CD40L interaction. The CD40-CD40L pathway is a promising treatment target for autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and lupus nephritis. The safety, tolerability, pharmacokinetics, and pharmacodynamics of repeated once-weekly BI 655064 subcutaneous dosing over 4 weeks were evaluated in a multiple-dose study in healthy subjects. Subjects (N = 40) were randomized 4:1 to four sequential BI 655064 dose groups (80, 120, 180, 240 mg) or to placebo. Safety and tolerability, plasma exposure, CD40 receptor occupancy, and CD40L-induced CD54 upregulation were assessed over 64 and 78 days for the 80- to 180-mg and 240-mg dose groups, respectively. BI 655064 exposure increased in a supraproportional manner, due to target-mediated drug clearance, for doses between 80 mg and 120 mg, but was near proportional for doses greater than 120 mg. Terminal half-life ranged between 6 and 8 days. Dose-dependent accumulation of BI 655064 supports the use of a loading dose in future clinical studies. Following 4 weeks of dosing, >90% CD40 receptor occupancy and inhibition of CD54 upregulation were observed at all dose levels, lasting for 17 days after the last dose. BI 655064 was generally well tolerated. There were no serious adverse events and the frequency and intensity of adverse events were similar for BI 655064 and placebo; no dose relationship or relevant signs of an acute immune reaction were observed. These findings support further investigation of BI 655064 as a potential treatment for autoimmune diseases.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Doenças Autoimunes/terapia , Antígenos CD40/imunologia , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
8.
Eur J Clin Pharmacol ; 74(2): 161-169, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127458

RESUMO

PURPOSE: The CD40-CD40L pathway is a promising treatment target for autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus and lupus nephritis. The safety, pharmacokinetics and pharmacodynamics of BI 655064, a novel humanised antagonistic anti-CD40 monoclonal antibody, were investigated in this first-in-human trial. METHODS: Healthy male subjects (n = 72) were randomised 3:1, within each BI 655064 dose group, to single intravenous (IV; 0.2-120 mg) or subcutaneous (SC; 40-120 mg) doses of BI 655064 or placebo. Safety, plasma exposure, CD40 receptor occupancy and CD40L-induced CD54 upregulation were assessed over 12 weeks. RESULTS: Adverse events (AEs) were reported in 43% of subjects (n = 31). Frequency and intensity of AEs were generally similar between BI 655064 and placebo and showed no dose relationship. The most frequent AEs were headache and nasopharyngitis. One mild rash and one local reaction occurred with SC BI 655064; two serious AEs were reported, both judged unrelated to BI 655064. Pharmacokinetic evaluation demonstrated a more than proportional increase in plasma exposure relative to BI 655064 dose, with a terminal half-life between 4 h and 4 days IV and approximately 5 days SC; doses ≥ 20 mg IV and 120 mg SC showed > 90% CD40 receptor occupancy and inhibition of CD54 upregulation, which lasted 7 days in the 120 mg IV and SC groups. CONCLUSIONS: Single doses up to 120 mg BI 655064 IV and SC were well tolerated and showed a high potential to block the CD40-CD40L pathway, supporting further clinical development of BI 655064 in patients with autoimmune disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01510782.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Antígenos CD40/antagonistas & inibidores , Administração Intravenosa , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/farmacologia , Ligante de CD40/farmacologia , Relação Dose-Resposta a Droga , Voluntários Saudáveis , Humanos , Injeções Subcutâneas , Molécula 1 de Adesão Intercelular/biossíntese , Masculino , Pessoa de Meia-Idade , Ensaio Radioligante , Método Simples-Cego , Adulto Jovem
9.
Bioanalysis ; 9(16): 1253-1264, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28766359

RESUMO

Flow cytometry is a powerful tool that can be used for the support of (pre)clinical studies. Although various white papers are available that describe the set-up and validation of the instrumentation (the flow cytometer) and validation of flow cytometry methods, to date no guidelines exist that address the requirements for performing flow cytometry in a regulated environment. In this manuscript, the European Bioanalysis Forum presents additional practice guidance on the use of flow cytometry in the support of drug development programs and addresses areas that are not covered in the previous publications. The concepts presented here are based on the consensus of discussions in the European Bioanalysis Forum Topic Team 32, in meetings in Barcelona, Limelette and multiple telephone conferences.


Assuntos
Retroalimentação , Citometria de Fluxo , Controle Social Formal , Métodos Analíticos de Preparação de Amostras , Europa (Continente) , Citometria de Fluxo/normas , Guias de Prática Clínica como Assunto
10.
Eur J Pharmacol ; 789: 68-74, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27393460

RESUMO

Inhibition of local cortisol regeneration from circulating cortisone by blocking 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) has been shown to ameliorate the risk factors associated with the metabolic syndrome. Chronic modulation of glucocorticoid homeostasis may result in hypothalamic-pituitary-adrenal (HPA) axis stimulation. HPA axis over-activation leading androgen excess would be undesirable in a therapeutic intervention designed to treat a chronic condition such as the metabolic syndrome. To address whether 11ß-HSD1 inhibition would lead to excess androgens, we treated female cynomolgus monkeys with a selective inhibitor, BI 135558, for 4 weeks. Continual action of the compound over the dosing period was confirmed by constant plasma exposure, and a maintained change in urinary glucocorticoid metabolites consistent with 11ß-HSD1 inhibition. No significant changes in adrenal function, as evidenced by an adrenocorticotropic hormone (ATCH) challenge, were observed. An examination of androgenic hormones revealed a slight increase in dehydroepiandrosterone sulfate (DHEA-S), while other hormones such as testosterone remained within reference values. Overall, treatment with BI 135558 in monkeys did not result in obvious over-activation of the HPA axis.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Oxazinas/farmacologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Piridonas/farmacologia , Animais , Inibidores Enzimáticos/farmacocinética , Feminino , Sistema Hipotálamo-Hipofisário/fisiologia , Macaca fascicularis , Oxazinas/farmacocinética , Sistema Hipófise-Suprarrenal/fisiologia , Piridonas/farmacocinética , Fatores de Tempo
11.
Diabetes Metab Res Rev ; 25(6): 577-86, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19618481

RESUMO

BACKGROUND: Acetyl-CoA carboxylases (ACC) 1 and 2 are central enzymes in lipid metabolism. To further investigate their relevance for the development of obesity and type 2 diabetes, expression of both ACC isoforms was analyzed in obese fa/fa Zucker fatty and Zucker diabetic fatty rats at different ages in comparison to Zucker lean controls. METHODS: ACC1 and ACC2 transcript levels were measured by quantitative real-time polymerase chain reaction in metabolically relevant tissues of Zucker fatty, Zucker diabetic fatty and Zucker lean control animals. Quantitative real-time polymerase chain reaction was also applied to measure ACC tissue distribution in human tissues. For confirmation on a protein level, quantitative mass spectrometry was used. RESULTS: Disease-related transcriptional changes of both ACC isoforms were observed in various tissues of Zucker fatty and Zucker diabetic fatty rats including liver, pancreas and muscle. Changes were most prominent in oxidative tissues of diabetic rats, where ACC2 was significantly increased and ACC1 was reduced compared with Zucker lean control animals. A comparison of the overall tissue distribution of both ACC isoforms in humans and rats surprisingly revealed strong differences. While in rats ACC1 was mainly expressed in lipogenic and ACC2 in oxidative tissues, ACC2 was predominant in oxidative and lipogenic tissues in humans. CONCLUSION: Our data support a potential role for both ACC isoforms in the development of obesity and diabetes in rats. However, the finding of fundamental species differences in ACC1 and ACC2 tissue expression might be indicative for different functions of both isoforms in humans and rats and raises the question to which degree these models are predictive for the physiology and pathophysiology of lipid metabolism in humans.


Assuntos
Acetil-CoA Carboxilase/metabolismo , Diabetes Mellitus/enzimologia , Regulação Enzimológica da Expressão Gênica , Obesidade/enzimologia , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/isolamento & purificação , Envelhecimento , Análise de Variância , Animais , Glicemia/análise , Peso Corporal , Dieta , Jejum/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Técnicas de Diluição do Indicador , Isoenzimas/genética , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Masculino , Especificidade de Órgãos , Fragmentos de Peptídeos/análise , Proteômica/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Ratos Zucker , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie , Espectrometria de Massas em Tandem , Triglicerídeos/sangue
12.
J Lipid Res ; 50(1): 22-31, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18769020

RESUMO

Nuclear hormone receptors liver X receptor (LXRalpha and LXRbeta) ligands are attractive approaches for the treatment of dyslipidemia and atherosclerosis. To further elucidate the function of LXRalpha in liver lipid metabolism in a disease-relevant animal model, the KKAy mouse, we used adenoviral vectors to selectively knock down LXRalpha gene expression. Out of five different short hairpin RNAs (shRNAs) that were tested in vitro, one construct was selected for detailed analysis of LXRalpha knockdown in vivo. Reduction of LXRalpha transcript levels to 48 +/- 13% compared with control virus transduction resulted in a significant downregulation of the LXRalpha-regulated lipogenic genes sterol-regulatory element binding protein-1c (SREBP1c) and stearoyl CoA desaturase 1 in vivo. Interestingly, ABCA1 and phoshoenolpyruvate carboxykinase 1 expression was not affected, whereas lipoprotein lipase (LPL) expression was found to be increased. In addition, 8 days after virus transduction, both plasma and liver triglycerides (TGs) were reduced by about 50%. Changes in TG levels were not due to reduced food intake in virus-treated animals, because pair-fed mice showed unchanged TG levels. Taken together, liver-specific knockdown of LXRalpha in vivo by shRNA reduced expression of lipogenic master genes, like SREBP1c, and improved the lipid profile of hypertriglyceridemic KKAy mice.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Lipídeos/química , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Adenoviridae/metabolismo , Animais , Linhagem Celular , Diabetes Mellitus Experimental , Hipertrigliceridemia/metabolismo , Lipase Lipoproteica/metabolismo , Receptores X do Fígado , Camundongos , Modelos Biológicos , Receptores Nucleares Órfãos , RNA/metabolismo , RNA Mensageiro/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
13.
Diabetes ; 56(9): 2235-41, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17596404

RESUMO

Type 2 diabetes is characterized by a progressive resistance of peripheral tissues to insulin. Recent data have established the lipid phosphatase SH2 domain-containing inositol phosphatase 2 (SHIP2) as a critical negative regulator of insulin signal transduction. Mutations in the SHIP2 gene are associated with type 2 diabetes. Here, we used hyperglycemic and hyperinsulinemic KKA(y) mice to gain insight into the signaling events and metabolic changes triggered by SHIP2 inhibition in vivo. Liver-specific expression of a dominant-negative SHIP2 mutant in KKA(y) mice increased basal and insulin-stimulated Akt phosphorylation. Protein levels of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase were significantly reduced, and consequently the liver produced less glucose through gluconeogenesis. Furthermore, SHIP2 inhibition improved hepatic glycogen metabolism by modulating the phosphorylation states of glycogen phosphorylase and glycogen synthase, which ultimately increased hepatic glycogen content. Enhanced glucokinase and reduced pyruvate dehydrogenase kinase 4 expression, together with increased plasma triglycerides, indicate improved glycolysis. As a consequence of the insulin-mimetic effects on glycogen metabolism, gluconeogenesis, and glycolysis, the liver-specific inhibition of SHIP2 improved glucose tolerance and markedly reduced prandial blood glucose levels in KKA(y) mice. These results support the attractiveness of a specific inhibition of SHIP2 for the prevention and/or treatment of type 2 diabetes.


Assuntos
Glicemia/metabolismo , Inibidores Enzimáticos/farmacologia , Gluconeogênese/fisiologia , Glucose/metabolismo , Glicogênio/metabolismo , Glicólise/fisiologia , Insulina/farmacologia , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Adenoviridae/enzimologia , Adenoviridae/genética , Animais , DNA , Ingestão de Alimentos , Teste de Tolerância a Glucose , Inositol Polifosfato 5-Fosfatases , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/genética , Valores de Referência
14.
Diabetes ; 53(7): 1920-6, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15220221

RESUMO

Increased supply of fatty acids to muscle and liver is causally involved in the insulin resistance syndrome. Using a tissue microdialysis technique in Wistar and Zucker fatty (ZF) rats, we determined tissue glycerol levels as a marker of lipolysis in gastrocnemius muscle (gMT), subcutaneous adipose (SAT), and visceral adipose tissue (VAT) as well as the reduction of plasma free fatty acids, glycerol, and triglycerides caused by the antilipolysis-specific adenosine-A1 receptor agonist (ARA). In Wistar and ZF rats, ARA significantly lowered dialysate glycerol levels in SAT, VAT, and gMT. Whereas in SAT and VAT the decrease in dialysate glycerol indicated adipocytic antilipolysis, this decrease in gMT was not caused by a direct effect of ARA on intramyocellular lipolysis, as demonstrated by the lack of inhibition of the protein kinase A activity ratio in gMT. In addition, no differences of the fed-starved-refed dynamics of intramyocellular triglyceride levels compared with untreated controls were measured by in vivo (1)H-spectroscopy, excluding any adenylate cyclase-independent antilipolysis in muscle. Treatment with ARA resulted in pronounced reductions of plasma free fatty acids, glycerol, and triglycerides. Furthermore, in ZF rats, ARA treatment caused an immediate improvement of peripheral insulin sensitivity measured by the euglycemic-hyperinsulinemic glucose clamp technique.


Assuntos
Lipólise , Obesidade/metabolismo , Receptor A1 de Adenosina/metabolismo , Tecido Adiposo/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ácidos Graxos não Esterificados/sangue , Técnica Clamp de Glucose , Glicerol/sangue , Glicerol/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Microdiálise , Músculo Esquelético/metabolismo , Ratos , Ratos Wistar , Ratos Zucker , Tela Subcutânea/metabolismo , Triglicerídeos/sangue , Vísceras
15.
Am J Physiol Endocrinol Metab ; 283(3): E604-11, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12169455

RESUMO

Suckling-age rats display endogenous circadian rhythmicity of metabolic rate (MR) with energy-saving, torpor-like decreases, which are sympathetically controlled and suppressed by leptin treatment. We investigated whether neonatal monosodium glutamate (MSG) treatment, known to cause arcuate nucleus damage and adult-age obesity, alters energy balance in the first two postnatal weeks. Continuously recorded MR and core temperatures (T(c)) show that MSG treatment disinhibits the periodic, sympathetically controlled, energy-saving drops of T(c) and MR. Increased energy expenditure thus explains reduced body fat at normal lean body mass found in MSG-treated pups artificially nourished identically to controls. In MSG-treated mother-reared pups, lean body mass is additionally reduced, suggesting that MSG also reduces suckling. Plasma leptin levels are similar in controls and MSG-treated pups but higher per unit of fat mass in the latter. We conclude that the postweaning development of MSG obesity and depressed thermogenesis are preceded by an early phase of increased energy expenditure with decreased fat deposition during suckling age and hypothesize cell damage in the arcuate nucleus to be involved in both.


Assuntos
Animais Lactentes/fisiologia , Peso Corporal/efeitos dos fármacos , Ritmo Circadiano , Metabolismo Energético/fisiologia , Glutamato de Sódio/farmacologia , Criação de Animais Domésticos/métodos , Animais , Animais Lactentes/crescimento & desenvolvimento , Composição Corporal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Feminino , Hipotálamo/efeitos dos fármacos , Hipotálamo/patologia , Leptina/sangue , Metabolismo/efeitos dos fármacos , Mães , Periodicidade , Ratos , Ratos Zucker
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