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1.
Pain Med ; 25(6): 380-386, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38407391

RESUMO

OBJECTIVE: In this study, we explored key prescription drug monitoring program-related outcomes among clinicians from a broad cohort of Massachusetts healthcare facilities following prescription drug monitoring program (PDMP) and electronic health record (EHR) data integration. METHODS: Outcomes included seven-day rolling averages of opioids prescribed, morphine milligram equivalents (MMEs) prescribed, and PDMP queries. We employed a longitudinal study design to analyze PDMP data over a 15-month study period which allowed for six and a half months of pre- and post-integration observations surrounding a two-month integration period. We used longitudinal mixed effects models to examine the effect of EHR integration on each of the key outcomes. RESULTS: Following EHR integration, PDMP queries increased both through the web-based portal and in total (0.037, [95% CI = 0.017, 0.057] and 0.056, [95% CI = 0.035, 0.077]). Both measures of clinician opioid prescribing declined throughout the study period; however, no significant effect following EHR integration was observed. These results were consistent when our analysis was applied to a subset consisting only of continuous PDMP users. CONCLUSIONS: Our results support EHR integration contributing to PDMP utilization by clinicians but do not support changes in opioid prescribing behavior.


Assuntos
Analgésicos Opioides , Registros Eletrônicos de Saúde , Padrões de Prática Médica , Programas de Monitoramento de Prescrição de Medicamentos , Humanos , Analgésicos Opioides/uso terapêutico , Massachusetts , Padrões de Prática Médica/estatística & dados numéricos , Estudos Longitudinais , Prescrições de Medicamentos/estatística & dados numéricos
2.
J Public Health Manag Pract ; 29(2): E37-E43, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36715601

RESUMO

West Virginia has struggled with an overdose epidemic for many years and continues to have the highest overdose death rate in the nation. However, through successful collaboration between the West Virginia Board of Pharmacy and the West Virginia Department of Health via its Violence and Injury Prevention Program, West Virginia has improved data quality, enhanced program development and implementation, and developed strategies to address the overdose epidemic. This multiagency collaboration plays an important role in addressing the overdose epidemic and promotes lasting interagency relationships. One strategy is overcoming barriers to maximizing and utilizing the Prescription Drug Monitoring Program, or PDMP. This strategy allows for a better understanding of a patient's prescription history and ensures safer prescribing practices. In addition, this strategic partnership facilitates the use of PDMP data for epidemiologic studies and public health surveillance, which results in sustainable analyses and dissemination of actionable data that are now driving public health action in West Virginia.


Assuntos
Overdose de Drogas , Programas de Monitoramento de Prescrição de Medicamentos , Humanos , Tomada de Decisão Clínica , Overdose de Drogas/epidemiologia , Overdose de Drogas/prevenção & controle , Vigilância em Saúde Pública , West Virginia/epidemiologia
3.
J Public Health Manag Pract ; 29(2): 262-270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36112160

RESUMO

OBJECTIVE: To determine whether any combinations of state-level public health activities were necessary or sufficient to reduce prescription opioid dispensing. DESIGN: We examined 2016-2019 annual progress reports, 2014-2019 national opioid dispensing data (IQVIA), and interview data from states to categorize activities. We used crisp-set Qualitative Comparative Analysis to determine which program activities, individually or in combination, were necessary or sufficient for a better than average decrease in morphine milligram equivalent (MME) per capita. SETTING: Twenty-nine US state health departments. PARTICIPANTS: State health departments implementing the Centers for Disease Control and Prevention's Prevention for States (PfS) program. MAIN OUTCOME: Combinations of prevention activities related to changes in the rate of prescription opioid MME per capita dispensing from 2014 to 2019. RESULTS: Three combinations were sufficient for greater than average state-level reductions in MME per capita: (1) expanding and improving proactive reporting in combination with enhancing the uptake of evidence-based opioid prescribing guidelines and not moving toward a real-time Prescription Drug Monitoring Program; (2) implementing or improving prescribing interventions for insurers, health systems, or pharmacy benefit managers in combination with enhancing the uptake of evidence-based opioid prescribing guidelines; and (3) not implementing or improving prescribing interventions for insurers, health systems, or pharmacy benefit managers in combination with not enhancing the uptake of evidence-based opioid prescribing guidelines. Interview data suggested that the 3 combinations indicate how state contexts and history with addressing opioid overdose shaped programming and the ability to reduce MME per capita. CONCLUSIONS: States successful in reducing opioid dispensing selected activities that built upon existing policies and interventions, which may indicate thoughtful use of resources. To maximize impact in addressing the opioid overdose epidemic, states and agencies may benefit from building on existing policies and interventions.


Assuntos
Overdose de Drogas , Overdose de Opiáceos , Humanos , Estados Unidos/epidemiologia , Analgésicos Opioides/efeitos adversos , Padrões de Prática Médica , Overdose de Drogas/epidemiologia
4.
Subst Abus ; 42(2): 227-235, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798024

RESUMO

Background: The Centers for Disease Control and Prevention's Prevention for States (PfS) program funded 29 state health departments to prevent opioid overdose by implementing evidence-based prevention strategies. The objectives of this analysis were to describe the scope of activities implemented across the four PfS strategies and identify implementation challenges. Methods: PfS recipients submitted annual progress reports (APRs) to state support staff at CDC from 2015 to 2017. APR data were used to calculate the number of required and optional activities implemented under each PfS strategy. APR data were qualitatively analyzed using a systematic content analysis approach to identify key implementation challenges. Results: From 2015 to 2017, PfS recipients implemented 177 activities across four strategies from 2015 to 2017. Cross-cutting implementation challenges were (1) multi-sector collaboration, (2) lack of knowledge and misperceptions about opioid used disorder (OUD) among some partners and local communities and; (3) management and access to opioid data among PfS recipients. Conclusions: PfS recipients implemented an array of prevention interventions to address the opioid overdose crisis and encountered several cross-cutting implementation challenges. Challenges and state driven solutions over the course of implementing PfS led to several lessons learned and actions that CDC enacted to continue to support and expand overdose prevention.


Assuntos
Overdose de Drogas , Overdose de Opiáceos , Transtornos Relacionados ao Uso de Opioides , Centers for Disease Control and Prevention, U.S. , Overdose de Drogas/prevenção & controle , Humanos , Epidemia de Opioides , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Estados Unidos
5.
FASEB J ; 28(12): 5172-83, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25154876

RESUMO

Previous evidence indicates that adiponectin possesses antifibrogenic activity in inhibiting liver fibrosis. Therapeutic strategies, however, are limited by adiponectin quaternary structure and effective concentrations in circulation. Here we postulate a novel molecular mechanism, whereby adiponectin targets focal adhesion kinase (FAK) activity and disrupts key features of the fibrogenic response. Adiponectin-null (Ad(-/-)) mice and wild-type littermates were exposed to either saline or carbon tetrachloride (CCl4) for 6 wk. CCl4-gavaged mice were also injected with attenuated adenoviral adiponectin (Ad-Adn) or Ad-LacZ for 2 wk. Hepatic stellate cells (HSCs) were treated with or without adiponectin to elucidate signal transduction mechanisms. In vivo delivery of Ad-Adn markedly attenuates CCl4-induced expression of key integrin proteins and markers of HSC activation: αv, ß3, ß1, α2(I) collagen, and α-smooth muscle actin. Confocal experiments of liver tissues demonstrated that adiponectin delivery also suppressed vinculin and p-FAK activity in activated HSCs. In vitro, adiponectin induced dephosphorylation of FAK, mediated by a physical association with activated tyrosine phosphatase, Shp2. Conversely, Shp2 knockdown by siRNA significantly attenuated adiponectin-induced FAK deactivation, and expression of TIMP1 and α2(I) collagen was abolished in the presence of adiponectin and si-FAK. Finally, we documented that either adiponectin or the synthetic peptide with adiponectin properties, ADP355, suppressed p-FAK in synthetic matrices with stiffness measurements of 9 and 15 kPa, assessed by immunofluorescent imaging and quantitation. The in vivo and in vitro data presented indicate that disassembly of focal adhesion complexes in HSCs is pivotal for hepatic fibrosis therapy, now that small adiponectin-like peptides are available.


Assuntos
Adiponectina/fisiologia , Adesões Focais , Células Estreladas do Fígado/citologia , Cirrose Hepática/terapia , Animais , Sequência de Bases , Primers do DNA , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Semin Liver Dis ; 33(4): 343-57, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24222092

RESUMO

Hepatocellular accumulation of free fatty acids (FFAs) in the form of triglycerides constitutes the metabolic basis for the development of nonalcoholic fatty liver disease (NAFLD). Recent data demonstrate that excess FFA hepatocyte storage is likely to lead to lipotoxicity and hepatocyte apoptosis. Hence, FFA-mediated hepatocyte injury is a key contributor to the pathogenesis of nonalcoholic steatohepatitis (NASH). Nonalcoholic steatohepatitis, obesity, type 2 diabetes, essential hypertension, and other common medical problems together comprise metabolic syndrome. Evidence suggests that peptide hormones from the L cells of the distal small intestine, which comprise the core of the enteroendocrine system (EES), play two key roles, serving either as incretins, or as mediators of appetite and satiety in the central nervous system. Recent data related to glucagon-like peptide-1 (GLP-1) and other known L-cell hormones have accumulated due to the increasing frequency of bariatric surgery, which increase delivery of bile salts to the hindgut. Bile acids are a key stimulus for the TGR5 receptor of the L cells. Enhanced bile-salt flow and subsequent EES stimulation may be central to elimination of hepatic steatosis following bariatric surgery. Although GLP-1 is a clinically relevant pharmacological analogue that drives pancreatic ß-cell insulin output, GLP-1 analogues also have independent benefits via their effects on hepatocellular FFA metabolism. The authors also discuss recent data regarding the role of the major peptides released by the EES, which promote satiety and modulate energy homeostasis and utilization, as well as those that control fat absorption and intestinal permeability. Taken together, elucidating novel functions for EES-related peptides and pharmacologic development of peptide analogues offer potential far-ranging treatment for obesity-related human disease.


Assuntos
Células Enteroendócrinas/metabolismo , Fígado Gorduroso/metabolismo , Hormônios Gastrointestinais/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Obesidade/metabolismo , Animais , Cirurgia Bariátrica , Fígado Gorduroso/etiologia , Fígado Gorduroso/terapia , Humanos , Hepatopatia Gordurosa não Alcoólica , Obesidade/complicações , Obesidade/cirurgia , Comunicação Parácrina , Transdução de Sinais
7.
Am J Physiol Gastrointest Liver Physiol ; 302(2): G225-35, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22038829

RESUMO

The aims of this study were designed to determine whether liraglutide, a long-acting glucagon-like peptide, could reverse the adverse effects of a diet high in fat that also contained trans-fat and high-fructose corn syrup (ALIOS diet). Specifically, we examined whether treatment with liraglutide could reduce hepatic insulin resistance and steatosis as well as improve cardiac function. Male C57BL/6J mice were pair fed or fed ad libitum either standard chow or the ALIOS diet. After 8 wk the mice were further subdivided and received daily injections of either liraglutide or saline for 4 wk. Hyperinsulinemic-euglycemic clamp studies were performed after 6 wk, revealing hepatic insulin resistance. Glucose tolerance and insulin resistance tests were performed at 8 and 12 wk prior to and following liraglutide treatment. Liver pathology, cardiac measurements, blood chemistry, and RNA and protein analyses were performed. Clamp studies revealed hepatic insulin resistance after 6 wk of ALIOS diet. Liraglutide reduced visceral adiposity and liver weight (P < 0.001). As expected, liraglutide improved glucose and insulin tolerance. Liraglutide improved hypertension (P < 0.05) and reduced cardiac hypertrophy. Surprisingly, liver from liraglutide-treated mice had significantly higher levels of fatty acid binding protein, acyl-CoA oxidase II, very long-chain acyl-CoA dehydrogenase, and microsomal triglyceride transfer protein. We conclude that liraglutide reduces the harmful effects of an ALIOS diet by improving insulin sensitivity and by reducing lipid accumulation in liver through multiple mechanisms including, transport, and increase ß-oxidation.


Assuntos
Cardiomegalia/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Adiposidade/efeitos dos fármacos , Animais , Cardiomegalia/etiologia , Fígado Gorduroso/etiologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Teste de Tolerância a Glucose , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Resistência à Insulina , Liraglutida , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Biochem J ; 440(3): 385-95, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21846328

RESUMO

Adiponectin is protective against hepatic fibrosis, whereas leptin promotes fibrosis. In HSCs (hepatic stellate cells), leptin signals via a JAK2 (Janus kinase 2)/STAT3 (signal transducer and activator of transcription 3) pathway, producing effects that enhance ECM (extracellular matrix) deposition. SOCS-3 (suppressor of cytokine signalling-3) and PTP1B (protein tyrosine phosphatase 1B) are both negative regulators of JAK/STAT signalling, and recent studies have demonstrated a role for adiponectin in regulating SOCS-3 expression. In the present study we investigate mechanisms whereby adiponectin dampens leptin signalling and prevents excess ECM production. We treated culture-activated rat HSCs with recombinant adiponectin, leptin, both or neither, and also treated adiponectin knockout (Ad-/-) and wild-type mice with leptin and/or carbon tetrachloride (CCl4) or saline. We analyse JAK2 and Ob-Rb (long form of the leptin receptor) phosphorylation, and PTP1B expression and activity. We also explore potential mechanisms through which adiponectin regulates SOCS-3-Ob-Rb association. Adiponectin inhibits leptin-stimulated JAK2 activation and Ob-Rb phosphorylation in HSCs, whereas both were increased in Ad-/- mice. Adiponectin stimulates PTP1B expression and activity in vitro, whereas PTP1B expression was lower in Ad-/-mice than in wild-type mice. Adiponectin also promotes SOCS-3-Ob-R association and blocks leptin-stimulated formation of extracellular TIMP-1 (tissue inhibitor of metalloproteinases-1)-MMP-1 (matrix metalloproteinase-1) complexes in vitro. These results suggest two novel mechanisms whereby adiponectin inhibits hepatic fibrosis: (i) by promoting binding of SOCS-3 to Ob-Rb, and (ii) by stimulating PTP1B expression and activity, thus inhibiting JAK2/STAT3 signalling at multiple points.


Assuntos
Citoproteção , Células Estreladas do Fígado/metabolismo , Leptina/fisiologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/fisiopatologia , Adiponectina/genética , Adiponectina/farmacologia , Adiponectina/fisiologia , Animais , Tetracloreto de Carbono , Células Cultivadas , Técnicas de Inativação de Genes , Humanos , Janus Quinase 2/metabolismo , Leptina/farmacologia , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores para Leptina/metabolismo , Proteínas Recombinantes/farmacologia , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo
9.
Hepatology ; 51(5): 1584-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20225248

RESUMO

UNLABELLED: Glucagon-like peptide 1 (GLP-1) is a naturally occurring peptide secreted by the L cells of the small intestine. GLP-1 functions as an incretin and stimulates glucose-mediated insulin production by pancreatic beta cells. In this study, we demonstrate that exendin-4/GLP-1 has a cognate receptor on human hepatocytes and that exendin-4 has a direct effect on the reduction of hepatic steatosis in the absence of insulin. Both glucagon-like peptide 1 receptor (GLP/R) messenger RNA and protein were detected on primary human hepatocytes, and receptor was internalized in the presence of GLP-1. Exendin-4 increased the phosphorylation of 3-phosphoinositide-dependent kinase-1 (PDK-1), AKT, and protein kinase C zeta (PKC-zeta) in HepG2 and Huh7 cells. Small interfering RNA against GLP-1R abolished the effects on PDK-1 and PKC-zeta. Treatment with exendin-4 quantitatively reduced triglyceride stores compared with control-treated cells. CONCLUSION: This is the first report that the G protein-coupled receptor GLP-1R is present on human hepatocytes. Furthermore, it appears that exendin-4 has the same beneficial effects in vitro as those seen in our previously published in vivo study in ob/ob mice, directly reducing hepatocyte steatosis. Future use for human nonalcoholic fatty liver disease, either in combination with dietary manipulation or other pharmacotherapy, may be a significant advance in treatment of this common form of liver disease.


Assuntos
Fígado Gorduroso/fisiopatologia , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Insulina/fisiologia , Receptores de Glucagon/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Exenatida , Fígado Gorduroso/prevenção & controle , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hepatócitos/metabolismo , Humanos , Peptídeos/farmacologia , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Peçonhas/farmacologia
10.
Hepatology ; 52(5): 1713-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20941777

RESUMO

UNLABELLED: Obesity is rapidly becoming a pandemic and is associated with increased carcinogenesis. Obese populations have higher circulating levels of leptin in contrast to low concentrations of adiponectin. Hence, it is important to evaluate the dynamic role between adiponectin and leptin in obesity-related carcinogenesis. Recently, we reported the oncogenic role of leptin including its potential to increase tumor invasiveness and migration of hepatocellular carcinoma (HCC) cells. In the present study we investigated whether adiponectin could antagonize the oncogenic actions of leptin in HCC. We employed HCC cell lines HepG2 and Huh7, the nude mice-xenograft model of HCC, and immunohistochemistry data from tissue-microarray to demonstrate the antagonistic role of adiponectin on the oncogenic actions of leptin. Adiponectin treatment inhibited leptin-induced cell proliferation of HCC cells. Using scratch-migration and electric cell-substrate impedance-sensing-based migration assays, we found that adiponectin inhibited leptin-induced migration of HCC cells. Adiponectin treatment effectively blocked leptin-induced invasion of HCC cells in Matrigel invasion assays. Although leptin inhibited apoptosis in HCC cells, we found that adiponectin treatment induced apoptosis even in the presence of leptin. Analysis of the underlying molecular mechanisms revealed that adiponectin treatment reduced leptin-induced Stat3 and Akt phosphorylation. Adiponectin also increased suppressor of cytokine signaling (SOCS3), a physiologic negative regulator of leptin signal transduction. Importantly, adiponectin significantly reduced leptin-induced tumor burden in nude mice. In HCC samples, leptin expression significantly correlated with HCC proliferation as evaluated by Ki-67, whereas adiponectin expression correlated significantly with increased disease-free survival and inversely with tumor size and local recurrence. CONCLUSION: Collectively, these data demonstrate that adiponectin has the molecular potential to inhibit the oncogenic actions of leptin by blocking downstream effector molecules.


Assuntos
Adiponectina/uso terapêutico , Carcinoma Hepatocelular/patologia , Leptina/antagonistas & inibidores , Neoplasias Hepáticas/patologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/prevenção & controle , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular , DNA de Neoplasias/análise , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Leptina/metabolismo , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/prevenção & controle , Camundongos , Camundongos Nus , Obesidade/complicações , Fosforilação , Transplante Heterólogo
11.
J Cell Biochem ; 110(5): 1195-207, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20564215

RESUMO

Adiponectin is an adipocytokine that was recently shown to be anti-fibrogenic in hepatic fibrosis. Leptin, on the other hand, promotes hepatic fibrosis. The purpose of the present study was to elucidate a mechanism (or mechanisms) whereby adiponectin dampens leptin signaling in activated hepatic stellate cells (HSCs), and prevents excess extracellular matrix production. Activated HSCs, between passages 2 and 5, were cultured and exposed to recombinant human adiponectin and recombinant leptin. Immunoblot analysis for SOCS-3, TIMP-1, and the phosphorylated species of Stat3 and adenosine monophosphate-activated protein kinase (AMPK) were conducted. We also examined MMP-1 activity by immunosorbant fluorimetric analysis. In HSCs, adiponectin-induced phosphorylation of AMPK, and subsequently suppressed leptin-mediated Stat3 phosphorylation and SOCS-3 induction. Adiponectin also blocked leptin-stimulated secretion of TIMP-1, and significantly increased MMP-1 activity, in vitro. To extend this study, we treated adiponectin knockout mice (Ad-/-) daily with 5 mg/kg recombinant leptin and/or carbon tetrachloride (2 ml/kg) for 6 weeks. Post-necropsy analysis was performed to examine for inflammation, and histological changes in the Ad-/- and wild-type mice. There was no significant difference in inflammation, or aminotransferases, between mice receiving carbon tetrachloride and leptin versus carbon tetrachloride alone. As anticipated, the combination of leptin and CCl(4) enhanced hepatic fibrosis in both wild-type and Ad-/- mice, as estimated by amount of collagen in injured livers, but wild-type mice had significantly higher levels of SOCS-3 and significantly lower levels of TIMP-1 mRNA and protein than did adiponectin KO mice exposed to both CCl(4) and leptin. We therefore conclude that the protective effects of adiponectin against liver fibrosis require AMPK activation, and may occur through inhibition of the Jak-Stat signal transduction pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Leptina/metabolismo , Cirrose Hepática/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Adiponectina/genética , Adiponectina/farmacologia , Animais , Western Blotting , Tetracloreto de Carbono , Células Cultivadas , Feminino , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Leptina/genética , Leptina/farmacologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Masculino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Transfecção
12.
Sci Transl Med ; 8(357): 357ra122, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27655848

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the Western world, and safe and effective therapies are needed. Bile acids (BAs) and their receptors [including the nuclear receptor for BAs, farnesoid X receptor (FXR)] play integral roles in regulating whole-body metabolism and hepatic lipid homeostasis. We hypothesized that interruption of the enterohepatic BA circulation using a luminally restricted apical sodium-dependent BA transporter (ASBT) inhibitor (ASBTi; SC-435) would modify signaling in the gut-liver axis and reduce steatohepatitis in high-fat diet (HFD)-fed mice. Administration of this ASBTi increased fecal BA excretion and messenger RNA (mRNA) expression of BA synthesis genes in liver and reduced mRNA expression of ileal BA-responsive genes, including the negative feedback regulator of BA synthesis, fibroblast growth factor 15. ASBT inhibition resulted in a marked shift in hepatic BA composition, with a reduction in hydrophilic, FXR antagonistic species and an increase in FXR agonistic BAs. ASBT inhibition restored glucose tolerance, reduced hepatic triglyceride and total cholesterol concentrations, and improved NAFLD activity score in HFD-fed mice. These changes were associated with reduced hepatic expression of lipid synthesis genes (including liver X receptor target genes) and normalized expression of the central lipogenic transcription factor, Srebp1c Accumulation of hepatic lipids and SREBP1 protein were markedly reduced in HFD-fed Asbt(-/-) mice, providing genetic evidence for a protective role mediated by interruption of the enterohepatic BA circulation. Together, these studies suggest that blocking ASBT function with a luminally restricted inhibitor can improve both hepatic and whole body aspects of NAFLD.


Assuntos
Ácidos e Sais Biliares/metabolismo , Dieta Hiperlipídica/efeitos adversos , Íleo/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Animais , Ceramidas/metabolismo , Colesterol/metabolismo , Óxidos N-Cíclicos/administração & dosagem , Óxidos N-Cíclicos/farmacologia , Fezes , Regulação da Expressão Gênica/efeitos dos fármacos , Teste de Tolerância a Glucose , Íleo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Transportadores de Ânions Orgânicos Dependentes de Sódio/deficiência , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/metabolismo , Simportadores/deficiência , Simportadores/metabolismo , Triglicerídeos/metabolismo , Tropanos/administração & dosagem , Tropanos/farmacologia
13.
J Nutr Biochem ; 26(3): 285-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25577467

RESUMO

UNLABELLED: Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome (MetS). Up to a third of NAFLD subjects are at risk for developing nonalcoholic steatohepatitis (NASH). Many rodent models fail to replicate both MetS and NASH. The purpose of this study was to develop a reliable mouse model of NASH and MetS using a diet containing cholesterol, saturated fat and carbohydrate that is reflective of Western diets of North Americans. EXPERIMENTAL DESIGN: We used adult male C57BL/6 J 4- to 5-week-old mice and administered a solid diet containing 0.2% cholesterol, 45% of its calories from fat, with 30% of the fat in the form of partially hydrogenated vegetable oil. We also provided carbohydrate largely as high-fructose corn syrup equivalent in water. In a separate cohort, we gave the identical diet in the absence of cholesterol. Glucose and insulin tolerance testing was conducted throughout the feeding period. The feeding was conducted for 16 weeks, and the mice were sacrificed for histological analysis, markers of MetS, liver inflammation, circulating lipids, as well as liver staining for fibrosis and alpha smooth muscle actin (α-SMA). RESULTS: We found that cholesterol significantly increased serum leptin, interleukin-6, liver weight and liver weight/body weight ratio, fibrosis and liver α-SMA. CONCLUSIONS: Mice administered a diet accurately reflecting patterns associated with humans afflicted with MetS can reliably replicate features of MetS, NASH and significant liver fibrosis. The model we describe significantly reduces the time by several months for development of stage 3 hepatic fibrosis.


Assuntos
Colesterol na Dieta/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental/efeitos adversos , Modelos Animais de Doenças , Fígado/fisiopatologia , Síndrome Metabólica/etiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Actinas/metabolismo , Adipocinas/sangue , Adipocinas/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Intolerância à Glucose/etiologia , Xarope de Milho Rico em Frutose/efeitos adversos , Hidrogenação , Resistência à Insulina , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/etiologia , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Síndrome Metabólica/fisiopatologia , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Fatores de Tempo
14.
PLoS One ; 6(9): e25269, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21957486

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a known outcome of hepatosteatosis. Free fatty acids (FFA) induce the unfolded protein response (UPR) or endoplasmic reticulum (ER) stress that may induce apoptosis. Recent data indicate ER stress to be a major player in the progression of fatty liver to more aggressive lesions. Autophagy on the other hand has been demonstrated to be protective against ER stress-induced cell death. We hypothesized that exendin-4 (GLP-1 analog) treatment of fat loaded hepatocytes can reduce steatosis by autophagy which leads to reduced ER stress-related hepatocyte apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: Primary human hepatocytes were loaded with saturated, cis- and trans-unsaturated fatty acids (palmitic, oleic and elaidic acid respectively). Steatosis, induced with all three fatty acids, was significantly resolved after exendin-4 treatment. Exendin-4 sustained levels of GRP78 expression in fat-loaded cells when compared to untreated fat-loaded cells alone. In contrast, CHOP (C/EBP homologous protein); the penultimate protein that leads to ER stress-related cell death was significantly decreased by exendin-4 in hepatocytes loaded with fatty acids. Finally, exendin-4 in fat loaded hepatocytes clearly promoted gene products associated with macroautophagy as measured by enhanced production of both Beclin-1 and LC3B-II, markers for autophagy; and visualized by transmission electron microscopy (TEM). Similar observations were made in mouse liver lysates after mice were fed with high fat high fructose diet and treated with a long acting GLP-1 receptor agonist, liraglutide. CONCLUSIONS/SIGNIFICANCE: GLP-1 proteins appear to protect hepatocytes from fatty acid-related death by prohibition of a dysfunctional ER stress response; and reduce fatty acid accumulation, by activation of both macro-and chaperone-mediated autophagy. These findings provide a novel role for GLP-1 proteins in halting the progression of more aggressive lesions from underlying steatosis in humans afflicted with NAFLD.


Assuntos
Autofagia/efeitos dos fármacos , Fígado Gorduroso/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Hepatócitos/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Peçonhas/química , Peçonhas/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/patologia , Animais , Apoptose/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Exenatida , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Frutose/efeitos adversos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Estilo de Vida , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Peptídeos/uso terapêutico , Análise de Sobrevida , Peçonhas/uso terapêutico
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