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1.
Cochrane Database Syst Rev ; 7: CD008161, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37439548

RESUMO

BACKGROUND: Different first-line drug classes for patients with hypertension are often assumed to have similar effectiveness with respect to reducing mortality and morbidity outcomes, and lowering blood pressure. First-line low-dose thiazide diuretics have been previously shown to have the best mortality and morbidity evidence when compared with placebo or no treatment. Head-to-head comparisons of thiazides with other blood pressure-lowering drug classes would demonstrate whether there are important differences. OBJECTIVES: To compare the effects of first-line diuretic drugs with other individual first-line classes of antihypertensive drugs on mortality, morbidity, and withdrawals due to adverse effects in patients with hypertension. Secondary objectives included assessments of the need for added drugs, drug switching, and blood pressure-lowering. SEARCH METHODS: Cochrane Hypertension's Information Specialist searched the Cochrane Hypertension Specialized Register, CENTRAL, MEDLINE, Embase, and trials registers to March 2021. We also checked references and contacted study authors to identify additional studies. A top-up search of the Specialized Register was carried out in June 2022. SELECTION CRITERIA: Randomized active comparator trials of at least one year's duration were included. Trials had a clearly defined intervention arm of a first-line diuretic (thiazide, thiazide-like, or loop diuretic) compared to another first-line drug class: beta-blockers, calcium channel blockers, alpha adrenergic blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, direct renin inhibitors, or other antihypertensive drug classes. Studies had to include clearly defined mortality and morbidity outcomes (serious adverse events, total cardiovascular events, stroke, coronary heart disease (CHD), congestive heart failure, and withdrawals due to adverse effects). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. MAIN RESULTS: We included 20 trials with 26 comparator arms randomizing over 90,000 participants. The findings are relevant to first-line use of drug classes in older male and female hypertensive patients (aged 50 to 75) with multiple co-morbidities, including type 2 diabetes. First-line thiazide and thiazide-like diuretics were compared with beta-blockers (six trials), calcium channel blockers (eight trials), ACE inhibitors (five trials), and alpha-adrenergic blockers (three trials); other comparators included angiotensin II receptor blockers, aliskiren (a direct renin inhibitor), and clonidine (a centrally acting drug). Only three studies reported data for total serious adverse events: two studies compared diuretics with calcium channel blockers and one with a direct renin inhibitor. Compared to first-line beta-blockers, first-line thiazides probably result in little to no difference in total mortality (risk ratio (RR) 0.96, 95% confidence interval (CI) 0.84 to 1.10; 5 trials, 18,241 participants; moderate-certainty), probably reduce total cardiovascular events (5.4% versus 4.8%; RR 0.88, 95% CI 0.78 to 1.00; 4 trials, 18,135 participants; absolute risk reduction (ARR) 0.6%, moderate-certainty), may result in little to no difference in stroke (RR 0.85, 95% CI 0.66 to 1.09; 4 trials, 18,135 participants; low-certainty), CHD (RR 0.91, 95% CI 0.78 to 1.07; 4 trials, 18,135 participants; low-certainty), or heart failure (RR 0.69, 95% CI 0.40 to 1.19; 1 trial, 6569 participants; low-certainty), and probably reduce withdrawals due to adverse effects (10.1% versus 7.9%; RR 0.78, 95% CI 0.71 to 0.85; 5 trials, 18,501 participants; ARR 2.2%; moderate-certainty). Compared to first-line calcium channel blockers, first-line thiazides probably result in little to no difference in total mortality (RR 1.02, 95% CI 0.96 to 1.08; 7 trials, 35,417 participants; moderate-certainty), may result in little to no difference in serious adverse events (RR 1.09, 95% CI 0.97 to 1.24; 2 trials, 7204 participants; low-certainty), probably reduce total cardiovascular events (14.3% versus 13.3%; RR 0.93, 95% CI 0.89 to 0.98; 6 trials, 35,217 participants; ARR 1.0%; moderate-certainty), probably result in little to no difference in stroke (RR 1.06, 95% CI 0.95 to 1.18; 6 trials, 35,217 participants; moderate-certainty) or CHD (RR 1.00, 95% CI 0.93 to 1.08; 6 trials, 35,217 participants; moderate-certainty), probably reduce heart failure (4.4% versus 3.2%; RR 0.74, 95% CI 0.66 to 0.82; 6 trials, 35,217 participants; ARR 1.2%; moderate-certainty), and may reduce withdrawals due to adverse effects (7.6% versus 6.2%; RR 0.81, 95% CI 0.75 to 0.88; 7 trials, 33,908 participants; ARR 1.4%; low-certainty). Compared to first-line ACE inhibitors, first-line thiazides probably result in little to no difference in total mortality (RR 1.00, 95% CI 0.95 to 1.07; 3 trials, 30,961 participants; moderate-certainty), may result in little to no difference in total cardiovascular events (RR 0.97, 95% CI 0.92 to 1.02; 3 trials, 30,900 participants; low-certainty), probably reduce stroke slightly (4.7% versus 4.1%; RR 0.89, 95% CI 0.80 to 0.99; 3 trials, 30,900 participants; ARR 0.6%; moderate-certainty), probably result in little to no difference in CHD (RR 1.03, 95% CI 0.96 to 1.12; 3 trials, 30,900 participants; moderate-certainty) or heart failure (RR 0.94, 95% CI 0.84 to 1.04; 2 trials, 30,392 participants; moderate-certainty), and probably reduce withdrawals due to adverse effects (3.9% versus 2.9%; RR 0.73, 95% CI 0.64 to 0.84; 3 trials, 25,254 participants; ARR 1.0%; moderate-certainty). Compared to first-line alpha-blockers, first-line thiazides probably result in little to no difference in total mortality (RR 0.98, 95% CI 0.88 to 1.09; 1 trial, 24,316 participants; moderate-certainty), probably reduce total cardiovascular events (12.1% versus 9.0%; RR 0.74, 95% CI 0.69 to 0.80; 2 trials, 24,396 participants; ARR 3.1%; moderate-certainty) and stroke (2.7% versus 2.3%; RR 0.86, 95% CI 0.73 to 1.01; 2 trials, 24,396 participants; ARR 0.4%; moderate-certainty), may result in little to no difference in CHD (RR 0.98, 95% CI 0.86 to 1.11; 2 trials, 24,396 participants; low-certainty), probably reduce heart failure (5.4% versus 2.8%; RR 0.51, 95% CI 0.45 to 0.58; 1 trial, 24,316 participants; ARR 2.6%; moderate-certainty), and may reduce withdrawals due to adverse effects (1.3% versus 0.9%; RR 0.70, 95% CI 0.54 to 0.89; 3 trials, 24,772 participants; ARR 0.4%; low-certainty). For the other drug classes, data were insufficient. No antihypertensive drug class demonstrated any clinically important advantages over first-line thiazides. AUTHORS' CONCLUSIONS: When used as first-line agents for the treatment of hypertension, thiazides and thiazide-like drugs likely do not change total mortality and likely decrease some morbidity outcomes such as cardiovascular events and withdrawals due to adverse effects, when compared to beta-blockers, calcium channel blockers, ACE inhibitors, and alpha-blockers.


Assuntos
Doença das Coronárias , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Hipertensão , Acidente Vascular Cerebral , Idoso , Feminino , Humanos , Masculino , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diuréticos/efeitos adversos , Insuficiência Cardíaca/tratamento farmacológico , Hipertensão/induzido quimicamente , Acidente Vascular Cerebral/tratamento farmacológico , Tiazidas/efeitos adversos , Pessoa de Meia-Idade
2.
J Affect Disord ; 325: 264-272, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36608852

RESUMO

BACKGROUND: While literature has suggested that the duration of a major depressive episode (MDE) may affect both symptomatic and functional outcomes in major depressive disorder (MDD), study designs are limited in their ability to isolate a causal relationship. METHODS: A targeted literature review was conducted using the MEDLINE database to assess whether there was an association between (1) shorter duration of an MDE, or (2) increased rapidity of symptom improvement, and MDD outcomes in adult patients. Given findings from the literature, we hypothesized that rapid symptom improvement could be associated with other longer-term clinical outcomes and used a previously-developed microsimulation model to test this hypothesis. The base case of the model replicated step-therapy treatment patterns, for 10,000 simulated patients, based on lines of therapy related to standard of care, observed remission rates, and observed time to relapse from the STAR*D study. In alternative scenario analyses, the step 1 remission rate was varied by +25 % and +50 % from the base case value to simulate the potential impact of improved earlier remission on disease trajectory and patient-level clinical outcomes. RESULTS: The literature review (N = 35 studies) suggests a statistically significant relationship between the duration of MDE or early symptom improvement and MDD outcomes. The microsimulation model corroborated these findings and demonstrated that increasing the rate of remission in step 1 results in patients experiencing decreased number of treatment steps, faster time to remission, decreased rate of reaching treatment-resistant depression, and delayed time to relapse. LIMITATIONS: Rates of relapse in STAR*D were deemed unreliable due to the high-loss of follow-up; rates of relapse for the MDD DTM were instead derived using parametric extrapolation methods (i.e., exponential, Weibull, log-logistic, Gaussian, log-normal, logistic). Adherence to treatment was assumed to be 100 %; however, non-adherence is expected to result in lower cumulative remission rates. CONCLUSION: Findings from the literature, coupled with quantification through a novel microsimulation model, demonstrate the potential impact of increased remission on disease trajectory and patient outcomes in MDD. While additional analyses with the model may be warranted to explore the impact of novel interventions on population health, including long-term outcomes (i.e., 5-year follow-up, lifetime follow-up), efforts by clinicians to increase remission early in the disease trajectory may improve long-term outcomes.


Assuntos
Transtorno Depressivo Maior , Adulto , Humanos , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/terapia , Transtorno Depressivo Maior/diagnóstico , Resultado do Tratamento , Depressão , Doença Crônica , Recidiva
3.
Artigo em Inglês | MEDLINE | ID: mdl-36638539

RESUMO

Objective: To identify and summarize data that describe the impact of effectively treating major depressive disorder (MDD) on the severity or risk of serious comorbidities.Data Sources: MEDLINE, Embase, PsycINFO, Cochrane Database of Systematic Reviews, and several congresses were searched. Searches included terms related to MDD, randomized controlled trials (RCTs), and physical comorbidities and were restricted to English-language publications. Searches were conducted in November 2019 for the previous 2 years for conference proceedings; no date restriction was applied to the database searches.Study Selection: Included studies were RCTs or meta-analyses that assessed depression therapies. Studies were required to report a statistically significant improvement in depression scores as well as the concurrent impact on comorbidities. A total of 1,997 articles were initially identified for screening.Data Extraction: Two investigators extracted data and assessed study quality.Results: A total of 30 studies, including 24 RCTs (N = 6,333) and 6 meta/pooled analyses of RCTs, were included. Findings in several comorbidity categories were mixed; for example, in half (4 of 8) of the identified studies in people with cardiovascular disease and depression, individuals who received treatment leading to reduced depressive symptoms compared with a control arm also had a significantly decreased incidence of cardiovascular events or significantly improved cardiac disease symptom/severity scores compared with controls. Significant improvements in comorbid disease severity observed alongside improvements in depressive symptoms were also noted in studies of comorbid Parkinson's disease, multiple sclerosis, chronic pain and fibromyalgia, and chronic obstructive pulmonary disease.Conclusions: Effective treatment of MDD may lead to a reduction in the severity of certain serious comorbidities. These results highlight the importance of appropriate and timely treatment of MDD.


Assuntos
Dor Crônica , Transtorno Depressivo Maior , Humanos , Comorbidade , Depressão/complicações , Depressão/epidemiologia , Depressão/terapia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/terapia , Revisões Sistemáticas como Assunto
4.
J Clin Psychiatry ; 83(6)2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36264099

RESUMO

Objective: To summarize the breadth of data exploring the relationship between major depressive disorder (MDD) and both the incidence and the disease course of a range of comorbidities.Data Sources: The authors searched MEDLINE, Embase, PsycINFO, Cochrane Database of Systematic Reviews, and several prespecified congresses. Searches included terms related to MDD and several comorbidity categories, restricted to those published in the English language from 2005 onward.Study Selection: Eligibility criteria included observational studies within North America and Europe that examined the covariate-adjusted impact of MDD on the risk and/or severity of comorbidities. A total of 6,811 articles were initially identified for screening.Data Extraction: Two investigators extracted data and assessed study quality.Results: In total, 199 articles were included. Depression was significantly (P < .05) associated with an increased incidence of dementia and Alzheimer's disease as well as cognitive decline in individuals with existing disease; increased incidence and worsening of cardiovascular disease/events (although mixed results were found for stroke); worsening of metabolic syndrome; increased incidence of diabetes, particularly among men, and worsening of existing diabetes; increased incidence of obesity, particularly among women; increased incidence and worsening of certain autoimmune diseases; increased incidence and severity of HIV/AIDS; and increased incidence of drug abuse and severity of both alcohol and drug abuse.Conclusions: The presence of MDD was identified as a risk factor for both the development and the worsening of a range of comorbidities. These results highlight the importance of addressing depression early in its course and the need for integrating mental and general health care.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Transtorno Depressivo Maior , Feminino , Humanos , Masculino , Doença de Alzheimer/complicações , Disfunção Cognitiva/complicações , Comorbidade , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/complicações
5.
Oncologist ; 25(1): e147-e159, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31578273

RESUMO

Treatment with immune checkpoint inhibitors (ICPIs) extends survival in a proportion of patients across multiple cancers. Tumor mutational burden (TMB)-the number of somatic mutations per DNA megabase (Mb)-has emerged as a proxy for neoantigen burden that is an independent biomarker associated with ICPI outcomes. Based on findings from recent studies, TMB can be reliably estimated using validated algorithms from next-generation sequencing assays that interrogate a sufficiently large subset of the exome as an alternative to whole-exome sequencing. Biological processes contributing to elevated TMB can result from exposure to cigarette smoke and ultraviolet radiation, from deleterious mutations in mismatch repair leading to microsatellite instability, or from mutations in the DNA repair machinery. A variety of clinical studies have shown that patients with higher TMB experience longer survival and greater response rates following treatment with ICPIs compared with those who have lower TMB levels; this includes a prospective randomized clinical trial that found a TMB threshold of ≥10 mutations per Mb to be predictive of longer progression-free survival in patients with non-small cell lung cancer. Multiple trials are underway to validate the predictive values of TMB across cancer types and in patients treated with other immunotherapies. Here we review the rationale, algorithm development methodology, and existing clinical data supporting the use of TMB as a predictive biomarker for treatment with ICPIs. We discuss emerging roles for TMB and its potential future value for stratifying patients according to their likelihood of ICPI treatment response. IMPLICATIONS FOR PRACTICE: Tumor mutational burden (TMB) is a newly established independent predictor of immune checkpoint inhibitor (ICPI) treatment outcome across multiple tumor types. Certain next-generation sequencing-based techniques allow TMB to be reliably estimated from a subset of the exome without the use of whole-exome sequencing, thus facilitating the adoption of TMB assessment in community oncology settings. Analyses of multiple clinical trials across several cancer types have demonstrated that TMB stratifies patients who are receiving ICPIs by response rate and survival. TMB, alongside other genomic biomarkers, may provide complementary information in selecting patients for ICPI-based therapies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/farmacologia , Biomarcadores Tumorais , Humanos , Imunoterapia/métodos , Mutação , Resultado do Tratamento , Carga Tumoral
6.
Curr Med Res Opin ; 35(3): 383-393, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30468090

RESUMO

OBJECTIVE: Postpartum depression (PPD) is the most common medical complication of childbirth. PPD can be disabling, with potential negative effects on maternal health-related quality-of-life (HRQoL) as well as on children and partners. The objective of this study was to systematically review and summarize recently published literature describing the humanistic burden of PPD on affected women, their children, and partners. METHODS: Databases including Embase, MEDLINE, and PsycINFO, as well as conference proceedings were searched for keywords related to PPD. Searches were initially conducted in February 2017 and restricted to the prior 5 years for databases and the prior 2 years for conference proceedings. Searches were updated in February 2018. Two researchers independently reviewed 1154 unique records according to pre-defined inclusion and exclusion screening criteria. RESULTS: Forty-eight studies were identified; over 40 studies assessed the effects of PPD on children of affected mothers, with many demonstrating a negative association with elements of parenting and childhood development. Furthermore, five studies that evaluated the effects of PPD symptoms on partners suggested that certain aspects of their relationships were negatively affected. Partners of affected women also experienced greater levels of their own stress, anxiety, and depression compared with partners of women without PPD symptoms. Despite limited data on HRQoL among women with PPD symptoms (four studies), a negative impact on physical and mental sub-scales was observed. CONCLUSIONS: Findings suggest that PPD symptoms have a substantial humanistic burden on affected mothers as well as on their children and partners.


Assuntos
Depressão Pós-Parto/psicologia , Adulto , Criança , Feminino , Ciências Humanas , Humanos , Qualidade de Vida
7.
Appl Health Econ Health Policy ; 16(5): 609-632, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30027533

RESUMO

BACKGROUND: Abuse of prescription opioids [opioid use disorder (OUD), poisoning, and fatal and non-fatal overdose] is a public health and economic challenge that is associated with considerable morbidity and mortality in the USA and globally. OBJECTIVE: To systematically review and summarize the health economics literature published over the last 5 years that describes the economic burden of abuse of prescription opioids. METHODS: Findings from searches of databases including MEDLINE, Embase, and Cochrane CENTRAL as well as hand searches of multiple conference abstracts were screened against predefined inclusion criteria to identify studies reporting cost and healthcare resource utilization (HRU) data associated with abuse of prescription opioids. RESULTS: A total of 49 unique studies were identified. Most of the studies examined direct costs and HRU, which were substantially higher for abusers of prescription opioids than non-abuser controls in several matched cohort analyses (US$20,343-US$28,718 vs US$9716-US$14,079 for mean direct combined annual healthcare costs reported in 6 studies). Although only a small number of studies reported indirect costs, these findings suggest a high societal burden related to productivity losses, absenteeism, morbidity, and mortality among those who abuse opioids. Studies of medication-assisted treatment demonstrated that factors such as adherence, dose, formulation (film or tablet), and relapse during treatment, were associated with direct costs and HRU among treated patients. CONCLUSIONS: This systematic literature review shows that abuse of prescription opioids is characterized by substantial direct healthcare costs, medical utilization, and related societal costs. Future research should further investigate the indirect costs of opioid abuse.


Assuntos
Efeitos Psicossociais da Doença , Transtornos Relacionados ao Uso de Opioides/economia , Transtornos Relacionados ao Uso de Substâncias/economia , Custos de Cuidados de Saúde , Humanos
8.
Curr Med Res Opin ; 33(11): 1995-2008, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28604117

RESUMO

OBJECTIVE: Prostate cancer is a highly prevalent form of cancer in older men and is one of the leading causes of death from cancer in men across the globe. Many therapeutic agents have been approved for patients with metastatic castration-resistant prostate cancer (mCRPC), particularly as a post-docetaxel treatment strategy. The objective of this systematic literature review was to assess published efficacy and safety data for select mCRPC therapies - such as abiraterone, cabazitaxel, and enzalutamide - in the post-docetaxel setting. METHODS: Database searches of MEDLINE, Embase, and Cochrane CENTRAL, in conjunction with hand searches of multiple congress abstracts, yielded 13 randomized studies and 107 non-randomized studies that met the inclusion criteria. RESULTS: Randomized studies demonstrated significant improvements in median overall survival (OS) outcomes over placebo for abiraterone (15.8 vs. 11.2 months) and enzalutamide (18.4 vs. 13.6 months), and similar significant improvements were noted for cabazitaxel over mitoxantrone (15.1 vs. 12.7 months). Differences in progression-free survival (PFS) were similarly significant, although variance in the criteria for measuring PFS may limit the extent to which these outcomes can be compared between studies. Non-randomized evidence included multiple publications from several early access and compassionate use programs with a primary objective to report safety outcomes. Results from these studies largely reflected the findings in randomized trials. CONCLUSIONS: Overall, there is a growing body of evidence for post-docetaxel treatment options available in patients with mCRPC. Further head-to-head trials or indirect treatment comparisons may be a valuable method to assess the comparative efficacy of these therapies.


Assuntos
Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Taxoides/administração & dosagem , Androstenos/administração & dosagem , Benzamidas , Ensaios de Uso Compassivo , Intervalo Livre de Doença , Docetaxel , Humanos , Masculino , Nitrilas , Feniltioidantoína/administração & dosagem , Feniltioidantoína/análogos & derivados , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxoides/efeitos adversos , Resultado do Tratamento
9.
Neuron ; 93(1): 132-146, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27989455

RESUMO

Lysosomes have traditionally been viewed as degradative organelles, although a growing body of evidence suggests that they can function as Ca2+ stores. Here we examined the function of these stores in hippocampal pyramidal neurons. We found that back-propagating action potentials (bpAPs) could elicit Ca2+ release from lysosomes in the dendrites. This Ca2+ release triggered the fusion of lysosomes with the plasma membrane, resulting in the release of Cathepsin B. Cathepsin B increased the activity of matrix metalloproteinase 9 (MMP-9), an enzyme involved in extracellular matrix (ECM) remodelling and synaptic plasticity. Inhibition of either lysosomal Ca2+ signaling or Cathepsin B release prevented the maintenance of dendritic spine growth induced by Hebbian activity. This impairment could be rescued by exogenous application of active MMP-9. Our findings suggest that activity-dependent exocytosis of Cathepsin B from lysosomes regulates the long-term structural plasticity of dendritic spines by triggering MMP-9 activation and ECM remodelling.


Assuntos
Cálcio/metabolismo , Catepsina B/metabolismo , Espinhas Dendríticas/metabolismo , Exocitose/fisiologia , Lisossomos/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Plasticidade Neuronal/fisiologia , Células Piramidais/metabolismo , Animais , Dendritos/metabolismo , Espinhas Dendríticas/fisiologia , Hipocampo/citologia , Masculino , Técnicas de Patch-Clamp , Células Piramidais/citologia , Células Piramidais/fisiologia , Ratos , Ratos Wistar , Transdução de Sinais
10.
Neuropharmacology ; 61(8): 1345-53, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21856316

RESUMO

The effects of the major schizophrenia susceptibility gene disease DTNBP1 on disease risk are likely to be mediated through changes in expression level of the gene product, dysbindin-1. How such changes might influence pathogenesis is, however, unclear. One possible mechanism is suggested by recent work establishing a link between altered dysbindin-1 expression and changes in surface levels of N-methyl-d-aspartate receptors (NMDAR), although neither the precise nature of this relationship, nor the mechanism underlying it, are understood. Using organotypic slices of rat hippocampus, we show that increased expression of dysbindin-1A in pyramidal neurons causes a severe and selective hypofunction of NMDARs and blocks induction of LTP. Cell surface, but not cytoplasmic, expression of the NR1 subunit of the NMDAR is decreased, suggesting dysregulation of NMDAR trafficking and, consistent with this, pharmacological inhibition of clathrin-dependent endocytosis is sufficient to reverse the deficit in NMDAR signaling. These results support the idea that the level of the NMDAR at the plasma membrane is modulated by changes in dysbindin-1 expression and offer further insight into the role of dysbindin-1 at an important cellular pathway implicated in schizophrenia.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica/fisiologia , Hipocampo/citologia , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Animais , Proteínas de Bactérias/genética , Biofísica , Células Cultivadas , Clatrina/farmacologia , Disbindina , Proteínas Associadas à Distrofina , Estimulação Elétrica , Embrião de Mamíferos , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/genética , Proteínas Luminescentes/genética , Masculino , Camundongos , N-Metilaspartato/farmacologia , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , Ratos , Ratos Wistar , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Bloqueadores dos Canais de Sódio/farmacologia , Tetrodotoxina/farmacologia , Transfecção/métodos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
11.
Can J Physiol Pharmacol ; 81(11): 1072-82, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14719043

RESUMO

The present study examined the effects of chronic activation of 5'-AMP-activated protein kinase (AMPK) on the oxidative capacity and myosin heavy chain (MHC) based fibre phenotype of rodent fast- and slow-twitch muscles. Sprague-Dawley rats received daily injections for 4 weeks of the known AMPK activator 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) or vehicle (control). The AICAR group displayed increases in hexokinase-II (HXK-II) activity, expression, and phosphorylation in fast-twitch muscles (P<0.001) but not in the slow-twitch soleus (SOL). In the AICAR group, citrate synthase (EC 4.1.3.7) and 3-hydroxyacyl-CoA-dehydrogenase (EC 1.1.1.35) were elevated 1.6- and 2.1-fold (P<0.05), respectively, in fast-twitch medial gastrocnemius (MG), and by 1.2- and 1.4-fold (P<0.05) in the slower-twitch plantaris (PLANT). No changes were observed in the slow-twitch SOL. In contrast, the activity of glyceraldehyde phosphate dehydrogenase (EC 1.2.1.12) remained unchanged in all muscles. AICAR treatment did not alter the MHC-based fibre type composition in fast- or slow-twitch muscles, as determined by immunohistochemical and electrophoretic analytical methods or by RT-PCR. We conclude that chronic activation of AMPK mimics the metabolic changes associated with chronic exercise training (increased oxidative capacity) in the fast-twitch MG and PLANT, but does not coordinately alter MHC isoform content or mRNA expression.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/administração & dosagem , Contração Muscular/efeitos dos fármacos , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Fibras Musculares de Contração Lenta/metabolismo , Fenótipo , Ribonucleotídeos/administração & dosagem , Proteínas Quinases Ativadas por AMP , Animais , Esquema de Medicação , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Masculino , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Contração Muscular/fisiologia , Fibras Musculares de Contração Rápida/enzimologia , Fibras Musculares de Contração Lenta/enzimologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley
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