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AIMS: To summarize the results of clinical studies of insulin icodec, an investigational insulin analog designed for once-weekly administration, in adults with type 1 and type 2 diabetes. METHODS: Thirteen published articles describing clinical studies of insulin icodec were identified in PubMed, and data pertinent to key study outcomes were selected for inclusion in this review. RESULTS: In insulin-naïve and insulin-treated individuals, icodec demonstrated efficacy in glycaemic control superior or noninferior to that of insulins glargine U100, glargine U300 and degludec. Icodec exhibited a safety profile comparable to marketed insulins, with the exception of hypoglycaemic event rates. CONCLUSIONS: As a once-weekly alternative to daily basal insulin, icodec is expected to improve patient adherence and satisfaction, reducing the required number of injections per year from 365 to 52 and providing a dosing option potentially attractive to a wide range of insulin users. However, clinical data suggest a notable risk of hypoglycaemia with weekly icodec administration, especially in individuals with type 1 diabetes.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Esquema de Medicação , Hipoglicemiantes , Insulina Glargina , Insulina de Ação Prolongada , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/sangue , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/uso terapêutico , Insulina Glargina/administração & dosagem , Insulina Glargina/uso terapêutico , Insulina/administração & dosagem , Insulina/análogos & derivados , Insulina/uso terapêutico , Hipoglicemia/induzido quimicamente , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Adulto , Resultado do Tratamento , Hemoglobinas Glicadas/metabolismo , Hemoglobinas Glicadas/análiseRESUMO
IN BRIEF Many patients with type 2 diabetes require high basal insulin doses, necessitating multiple injections, increasing patient burden, and resulting in reduced treatment adherence. This randomized, controlled, crossover trial compared the efficacy, safety, and patient-reported outcomes for a concentrated formulation of insulin degludec (200 units/mL) to those of insulin glargine in patients requiring high doses of basal insulin. By offering equivalent glycemic control while reducing the rate of confirmed hypoglycemia and the number of injections required for administration, insulin degludec 200 units/mL may be preferred by patients with type 2 diabetes who require high basal insulin doses.
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OBJECTIVE: To investigate the association between 25-hydroxyvitamin D [25(OH)D] levels prior to liver transplantation (LT) and the development of acute cellular rejection (ACR) within the first year post LT. METHODS: This retrospective study included 275 consecutive LTs performed in 262 patients at Mayo Clinic in Jacksonville, Florida over 13 months. A total of 149 patients met the inclusion criteria. The correlations between 25(OH)D levels and the development, severity, and number of biopsy-proven ACR episodes were assessed. RESULTS: The prevalence of 25(OH)D levels <30 ng/mL was 92%. No association was found between pre LT 25(OH)D levels and the diagnosis of ACR (P = .61). Mean ± SD pre LT 25(OH)D levels were 16.1 ± 6.8 ng/mL for 48 subjects with no rejection, 16.1 ± 8.2 ng/mL for those with a mild first episode of ACR (n = 58), and 18.4 ± 12.4 ng/mL for those who experienced a moderate/severe first ACR (n = 39). However, in a subgroup analysis of patients with 25(OH)D levels <30 ng/mL, there was a statistically significant negative correlation (P = .0252) between 25(OH) D level and the ACR rate. CONCLUSION: Vitamin D insufficiency and deficiency prior to LT was prevalent in our cohort. There was no statistically significant association between low 25(OH)D levels and the diagnosis or severity of ACR or the number of rejection episodes within the first year post LT. However, there was a negative correlation between 25(OH)D levels below 30 ng/mL and the rate of ACR within 1 year post LT.
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Rejeição de Enxerto/sangue , Transplante de Fígado/efeitos adversos , Vitamina D/análogos & derivados , Doença Aguda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vitamina D/sangueRESUMO
There is emerging evidence in the literature to suggest that disruption of the normal circadian rhythm (sleep-wake cycle signalling) is a potential risk factor to explain the increased incidence of metabolic syndrome. Over the last century, obesity, diabetes and other components of metabolic syndrome have been on the rise. On the other hand, the amount of sleep has decreased from an average of 6-8 h per night. Furthermore, the quality of sleep has declined with more individuals voluntarily decreasing their amount of sleep to work or enjoy leisure activities. Over the last decade, researchers have examined the relationship between disruption in human circadian system and the emergence of symptoms related to metabolic syndrome. Indeed, epidemiological studies suggest a relation between sleep duration and diabetes and obesity. Moreover, experimental animal and human studies suggest such a relation. These studies propose optimum sleep duration of 7-8 h per night to avoid circadian rhythm disruption and suggest that sleep disturbance, whether iatrogenic or disease-related, should be considered as a risk factor for metabolic syndrome, and be addressed. This field is in its infancy and further understanding of specific pathophysiological pathways of circadian desynchronisation will help in developing novel preventive and therapeutic strategies.
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Síndrome Metabólica/fisiopatologia , Obesidade/fisiopatologia , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Humanos , Estilo de Vida , Síndrome Metabólica/etiologia , Obesidade/complicações , Fatores de Risco , Sono , Transtornos do Sono do Ritmo Circadiano/complicaçõesRESUMO
Icosapent ethyl (IPE) was the first fish oil product the US Food and Drug Administration (FDA) approved to reduce the risk of atherosclerotic cardiovascular disease (ASCVD) in adults. IPE is an esterified version of eicosapentaenoic acid (EPA) and acts as a prodrug in the body to exert its effects. IPE affects the body primarily through triglyceride (TG) reduction and was initially indicated for hypertriglyceridemia in addition to statin therapy or for patients with statin intolerances. Various studies have investigated this agent, and multiple subanalyses have been conducted since the FDA approval. These subanalyses have assessed factors such as sex, statin therapy, high-sensitivity C-reactive protein levels (hs-CRP), and various inflammatory biomarkers in groups of patients taking IPE. This article aims to provide a critical review of the clinical data available regarding cardiovascular benefits of IPE in patients with ASCVD and its value as a treatment option for patients with elevated TG levels.
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Aterosclerose , Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipertrigliceridemia , Humanos , Ácido Eicosapentaenoico/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/tratamento farmacológico , Fatores de Risco , Hipertrigliceridemia/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Fatores de Risco de Doenças Cardíacas , TriglicerídeosRESUMO
Type 2 diabetes mellitus is a chronic disease most often characterized by increased glucose levels. When blood glucose levels are inadequately controlled or left untreated, the result is a variety of microvascular and macrovascular complications. To prevent these outcomes, many medications are available to manage type 2 diabetes mellitus and prevent disease progression. However, most of the medications available to date only target a few of the physiological defects caused by diabetes and may come with side effects that make adherence to the medication improbable. Imeglimin, a medication currently under investigation in the United States and approved in Japan, is a novel, first-in-its-class medication with a mechanism that is currently understood to target multiple pathways to provide glycemic control. This review aims to present and discuss the current clinical and scientific evidence pertaining to imeglimin.
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Diabetes Mellitus Tipo 2 , Glicemia/metabolismo , Humanos , Japão , Triazinas/uso terapêutico , Estados UnidosRESUMO
There is ample empiric evidence to indicate that oxidative stress contributes to the pathogenesis of coronary artery disease and has a key role in the onset and progression of diabetes and its complications. Diabetes leads to depletion of the cellular antioxidant defense system and is associated with an increase in the production of free radicals. Oxidative stress can be the result of multiple pathways. Some of these are related to substrate-driven overproduction of mitochondrial reactive oxygen species, advanced glycation end product formation, glucose autoxidation, and depletion of micronutrients and cellular elements with antioxidative properties. There are numerous observational studies in the literature showing a beneficial outcome of the consumption of antioxidant vitamins. However, the interventional trials portray a different picture. The divide between the robust experimental evidence of the pathogenetic role of increased oxidative load in diabetes and the overwhelming failure of antioxidants to show any health benefits in clinical trials may well be characterized as the "antioxidant paradox."
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Antioxidantes/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Antioxidantes/metabolismo , Diabetes Mellitus/etiologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Feminino , Radicais Livres/metabolismo , Glucose/metabolismo , Produtos Finais de Glicação Avançada/fisiologia , Humanos , Masculino , Micronutrientes/metabolismo , Micronutrientes/uso terapêutico , Oxirredução , Estresse Oxidativo/fisiologia , Espécies Reativas de OxigênioRESUMO
There are numerous treatment options currently available for patients with type 2 diabetes mellitus; however, a multitude of patients continue to have inadequately controlled glycemic levels with their current antihyperglycemic regimen. Furthermore, the American Diabetes Association guidelines increasingly highlight the importance of multifactorial management and optimizing medication regimens that include cardiovascular, renal, and/or weight benefits in patients with type 2 diabetes mellitus. Glucagon-like peptide-1 receptor agonists belong to a novel class of type 2 diabetes mellitus agents that are becoming increasingly prevalent owing to their ability to improve glycemic status without the risk of hypoglycemia. Currently, there are three US Food and Drug Administration-approved glucagon-like peptide-1 receptor agonists, subcutaneous semaglutide, dulaglutide, and liraglutide, that also have an indication for reducing major adverse cardiovascular events in patients with type 2 diabetes mellitus and established cardiovascular disease. However, these agents are not often the first options because of their subcutaneous administration. Nevertheless, co-formulation of oral semaglutide with an absorption enhancer has shown to increase its bioavailability and has made its oral absorption possible. In the PIONEER trials, oral semaglutide effectively lowered blood glucose levels, and showed benefits on weight and cardiovascular outcomes; however, there is no Food and Drug Administration indication approved yet as the SOUL trial is still ongoing. Such characteristics of oral semaglutide may improve and increase its use compared to subcutaneous agents and possibly lead to earlier cardiovascular protection in addition to achieving glycemic control.
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Diabetes Mellitus Tipo 2 , Administração Oral , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Peptídeos Semelhantes ao Glucagon , Humanos , Hipoglicemiantes/efeitos adversosRESUMO
Despite the widespread use of statins and ezetimibe to decrease low-density lipoprotein cholesterol (LDL-C) levels and associated atherosclerotic cardiovascular disease (ASCVD), many patients do not achieve adequate LDL-C lowering as per the recommended American College of Cardiology (ACC)/American Heart Association (AHA) and European Society of Cardiology (ESC)/European Atherosclerosis Society (EAS) guidelines and demonstrate residual cardiovascular risk. The introduction of proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibitors in 2015 was a promising addition to hypercholesterolemia therapies, but their cost and subcutaneous administration has limited their use, and therefore, new affordable and patient friendly treatment strategies are crucial to help reduce ASCVD risk. Bempedoic acid, a drug currently under investigation, is a small molecule that has been shown to upregulate LDL receptors, decrease LDL-C, and reduce atherosclerotic plaque formation in hypercholesterolemic patients. Furthermore, bempedoic acid is a prodrug that becomes activated by an enzyme expressed primarily in the liver, allowing it to avoid the potential myotoxicity associated with statin therapy. The purpose of this review is to summarize the major clinical studies evaluating bempedoic acid and describe its potential addition to currently approved lipid-lowering therapies.
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Anticolesterolemiantes/uso terapêutico , Ácidos Dicarboxílicos/uso terapêutico , Ezetimiba/uso terapêutico , Ácidos Graxos/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , LDL-Colesterol/metabolismo , Ácidos Dicarboxílicos/administração & dosagem , Ácidos Dicarboxílicos/efeitos adversos , Combinação de Medicamentos , Dislipidemias/tratamento farmacológico , Ezetimiba/administração & dosagem , Ezetimiba/efeitos adversos , Ácidos Graxos/administração & dosagem , Ácidos Graxos/efeitos adversos , Humanos , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores de LDL/biossínteseRESUMO
Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Because of these associated risks, managing diabetes and CVD, including heart failure (HF), has become a joint effort to reduce the risk of adverse outcomes. Although many patients with T2DM are receiving preventive therapies for CVD, their residual risk remains high for atherosclerotic CVD (ASCVD). Recent data regarding the use of antidiabetic medications to prevent negative cardiovascular outcomes has revealed a positive association with reduced major adverse cardiovascular events (MACE). One class of medications, sodium-glucose cotransporter-2 (SGLT-2) inhibitors, are at the forefront of the cardiovascular outcomes prevention discussion. The clinical data presented in this review indicate the potential cardiovascular benefits of SGLT-2 inhibitors in patients with CVD and its potential value as a treatment option in preventing CVD in various patient populations.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Fatores de Risco Cardiometabólico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Comorbidade , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Hipoglicemiantes/farmacologiaRESUMO
Diabetes is a significant and independent risk factor for atherosclerotic cardiovascular disease (ASCVD), leading to morbidity and mortality among this population. The prevention of macrovascular complications, such as CVD, peripheral arterial disease, and cerebrovascular accident, in patients with diabetes is obtained through multifactorial risk reduction, including mixed dyslipidemia management and adequate glycemic control. For patients with diabetes, it is crucial to initiate adequate dyslipidemia therapy to achieve recommended low-density lipoprotein cholesterol (LDL-C) goal of <70 mg/dL or target non-high-density lipoprotein goal of <100 mg/dL. Lipid-lowering therapies (LLTs), such as statins and ezetimibe, are the cornerstone for plasma LDL-C lowering; however, individuals with diabetes are often unable to achieve target lipid goals with these therapies alone and frequently require additional treatments. A new class of LLTs, proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors, provides a novel approach to lowering lipids in persons with high CV risk, such as those with diabetes. The clinical data presented in this review indicate the potential benefits of alirocumab in patients with diabetes and its value as a treatment option in patients with diabetic dyslipidemia with no significant safety concerns.
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OBJECTIVE: To determine the ability to predict the development of Cushing's syndrome (CS) by immunostaining prior to its clinical recognition. DESIGN: In the current report, we demonstrated that a medullary thyroid carcinoma (MTC) patient had the ability to develop CS several years before its clinical recognition. Special stains on tumor tissue confirmed the presence of ectopic adrenocorticotropic hormone (ACTH) 3 years before his clinical presentation of CS. Subsequently, we identified eight MTC patients and reviewed their records to determine whether there was clinical or laboratory evidence of CS. Tissue blocks were obtained from the primary tumor and metastasic lesions for ACTH staining and for proopiomelanocortin messenger ribonucleic acid (POMC mRNA) in situ hybridization. Chromogranin A staining was also performed. MAIN OUTCOME: ACTH staining did not detect ectopic ACTH. However, measuring ACTH precursor (POMC mRNA) by in situ hybridization confirmed the diagnosis, which preceded the patient's clinical presentation by 3 years. We also found that in a small series of eight MTC patients, most with metastatic disease, there was no histologic evidence of ACTH or POMC production. CONCLUSION: Our current report demonstrates that ACTH staining may not detect ACTH, but measuring POMC mRNA by in situ hybridization is very helpful in confirming the source of ectopic ACTH production.
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Hormônio Adrenocorticotrópico/metabolismo , Síndrome de Cushing/epidemiologia , Pró-Opiomelanocortina/genética , RNA Mensageiro/genética , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Valor Preditivo dos Testes , Neoplasias da Glândula Tireoide/patologiaRESUMO
Objective. To present a complicated case of differentiated thyroid carcinoma (DTC) with metastases to the skull that was evident on I-131 whole body scan (WBS) but negative on other imaging modalities in a low risk patient. Methods. We will discuss clinical course, imaging, pathological findings, and treatment of the patient with skull metastasis from DTC. Pertinent literature on imaging and pathology findings as well as radioactive iodine (RAI) treatment impact on quality of life and survival in patients with bone metastases from DTC will be reviewed. Results. The patient is a 37-year-old woman with a diagnosis of DTC who had focal areas of increased uptake in the head on WBS with no correlative findings on CT and MRI. Initially, false positive findings were suspected since patient had a low risk for developing metastases. However, the persistent findings on post-RAI treatment WBS, following two courses of treatment, were highly concerning for metastatic bone disease. WBC performed 6 months following the second RAI treatment revealed resolution of the findings. Conclusions. False positive findings in WBS are frequent and may be due to contamination, perspiration, or folliculitis of the scalp as well as benign lesions such as meningioma, hematoma, cavernous angioma, and metallic sutures. However, metastatic disease should always be considered even if the patient has low risk of distant metastatic disease and correlative images do not support the diagnosis. RAI therapy appears to improve the survival rates and quality of life of thyroid cancer patients with bone metastases based on retrospective studies.
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OBJECTIVE: To review and assess the role of vitamin D in the onset, progression, and relapse of multiple sclerosis (MS), based on evidence acquired from the analysis of preclinical, observational, and interventional studies. METHODS: All English language literature in MEDLINE (January 1969 through April 2012) was searched for observational and interventional studies on the dosage effect of vitamin D on the onset, progression, and relapse rate of MS. The medical subject heading (MeSH) terms used in the search included Vitamin D and Multiple Sclerosis. Additional publications and abstracts were identified from review articles and from the references cited in the previously found articles. In addition to the experimental studies, only those human studies that specified the population size, doses of vitamin D used, and the resulting effect on MS were considered. RESULTS: Vitamin D deficiency is very common among MS patients. Multiple preclinical studies have shown that vitamin D is a potent regulator of inflammation in MS. Most observational studies support an association between high vitamin D levels and a reduced risk of developing MS. However, conflicting results have been reported by observational studies on the correlation between vitamin D and MS severity and by interventional studies using vitamin D as a therapeutic agent for MS. CONCLUSION: Vitamin D deficiency in MS patients should be avoided. In addition, the risk of developing MS might be reduced by maintaining optimal vitamin D levels in the healthy population. Larger randomized interventional trials are needed to clarify the therapeutic effect of vitamin D in MS.
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Esclerose Múltipla/etiologia , Deficiência de Vitamina D/complicações , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Suplementos Nutricionais , Progressão da Doença , Humanos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/fisiopatologia , Índice de Gravidade de Doença , Deficiência de Vitamina D/tratamento farmacológicoRESUMO
Coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM) is associated with increased immediate and long-term mortality compared with patients without T2DM. The amplified incidence of CAD stems partly from the aggregation of multiple risk factors, such as obesity, dyslipidemia, and hypertension, which occur in this population. In addition, there appear to be increased forces at play at the molecular and vascular levels in these individuals, which is evidenced by the increased thrombosis and inflammation that is seen in those with diabetic atherosclerosis. Hence, there is a growing need to emphasize early and vigilant risk factor management in patients with T2DM to help reduce their burden of cardiovascular-related mortality. In this article, we review the primary and secondary prevention measures as well as the management of CAD in patients with T2DM.
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Doença da Artéria Coronariana/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Programas de Rastreamento/métodos , Prevenção Secundária/métodos , Doença da Artéria Coronariana/etiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Gerenciamento Clínico , Humanos , Fatores de RiscoRESUMO
Increased oxidative stress and endoplasmic reticulum stress (ER stress) have been implicated in atherosclerosis. Estrogens have potent antioxidant activity but their effects on ER stress have not been well studied. Therefore, we studied the effects of estradiol and related sex steroids on dextrose-induced ER stress and superoxide (SO) generation in human umbilical vein endothelial cells (HUVECs). Oxidative stress was measured using hydroethidine fluorescence and MCLA chemiluminescence. ER stress was measured with an ER stress-sensitive secreted alkaline phosphatase (ES-TRAP) assay and by Western blot analysis of the expression of GRP78, JNK1, and phosphorylated JNK1, markers for ER stress. A supraphysiological dextrose concentration (27.5mM) increased ER stress and SO generation compared to treatment with a physiological concentration (5.5mM) of dextrose. In the presence of estradiol or testosterone (T), ER stress and SO generation were significantly reduced. In contrast to T-treated cells, dihydrotestosterone and 5-methyltestosterone were ineffective at alleviating ER stress or SO generation. When HUVECs were treated with T and the aromatase inhibitor 4-hydroxy-4-androstene-3,17-dione, T was no longer effective at suppressing ER stress or inhibiting SO generation. Changes in GRP78 expression and JNK activity in HUVECs support the results obtained in the ES-TRAP assay. These results indicate that dextrose-induced endoplasmic reticulum stress and superoxide generation are reversed by estradiol and testosterone; however, the latter requires aromatase-dependent conversion to estradiol.
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Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estradiol/farmacologia , Superóxidos/antagonistas & inibidores , Testosterona/farmacologia , Androstenodiona/análogos & derivados , Androstenodiona/farmacologia , Inibidores da Aromatase/farmacologia , Aterosclerose/metabolismo , Chaperona BiP do Retículo Endoplasmático , Células Endoteliais/efeitos dos fármacos , Glucose/farmacologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Células Hep G2 , Humanos , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Superóxidos/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacosRESUMO
AIMS: Smokers have lower plasma concentrations of high-density lipoprotein (HDL) cholesterol and apolipoprotein A-I (apo A-I) compared with nonsmokers. To determine the molecular basis of this observation, the effect of activation of the aryl hydrocarbon receptor (AhR) on apo A-I gene expression was examined. MAIN METHODS: HepG2 cells were treated with AhR receptor agonists benzo(a)pyrene (BaP) and CAY10465, and AhR receptor antagonist CAY10464 and apo A-I protein, mRNA levels and promoter activity were measured. The effect of nicotine on apo A-I protein secretion was also tested. Using a series or apo A-I gene promoter deletion constructs, a xenobiotic response element (XRE) was identified. KEY FINDINGS: Treatment of HepG2 cells with the AhR receptor agonists BaP and CAY10465, inhibited apo A-I protein synthesis while nicotine, which does not bind AhR had no effect. Benzo(a)pyrene treatment also suppressed apo A-I mRNA and gene promoter activity. Treatment of HepG2 cells with the AhR receptor antagonist CAY10464 reversed the suppressive effect of BaP on apo A-I gene expression. A putative xenobiotic response element (XRE) was identified between nucleotides -325 and -186 (relative to the transcriptional start site, +1). SIGNIFICANCE: These results suggest that the cigarette smoking related environmental contaminant BaP promotes hypoalphalipoproteinemia in part through activation of the hepatic AhR.
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Apolipoproteína A-I/genética , Hipoalfalipoproteinemias/etiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Fumar/efeitos adversos , Apolipoproteína A-I/metabolismo , Benzopirenos/farmacologia , Western Blotting , Linhagem Celular , Deleção de Genes , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Nicotina/farmacologia , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/antagonistas & inibidoresRESUMO
AIM: Hyperglycemia-induced endothelial cell dysfunction can be the result of increased oxidative stress and concomitant increase in endoplasmic reticulum (ER) stress. To test the extent of coupling between these two stresses, the effect of antioxidant vitamins on glucose-induced oxidative stress and ER stress in endothelial cells were studied. METHODS: Human umbilical vein endothelial cells (HUVEC) were treated with physiological (5.5mM) or supra-physiological (27.5mM) dextrose concentrations, and ER stress and oxidative stress were measured. Additional experiments were carried out in HUVEC over-expressing exogenous glucose transporter-1 (Glut-1) and treated with 5.5mM dextrose. RESULTS: Supra-physiological dextrose concentrations increased both ER stress and oxidative stress. However, while oxidative stress could be effectively inhibited with alpha-tocopherol and ascorbic acid, these antioxidants had no effect on ER stress. Increasing intracellular glucose levels by exogenous expression of Glut-1 in endothelial cells also increased oxidative stress and ER stress. Whereas the oxidative stress in these cells was reduced with alpha-tocopherol and ascorbic acid and dimethylsulfoxide, the ER stress could not be ameliorated with alpha-tocopherol and ascorbic acid. CONCLUSIONS: These results indicate that ER stress can be uncoupled from oxidative stress and antioxidants can ameliorate the latter without altering the ER stress induced by hyperglycemia.
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Antioxidantes/farmacologia , Células Endoteliais/fisiologia , Glucose/farmacologia , Hiperglicemia/fisiopatologia , Estresse Oxidativo/fisiologia , Fosfatase Alcalina/metabolismo , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacologia , Divisão Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Transportador de Glucose Tipo 1/genética , Humanos , Cinética , Estresse Oxidativo/efeitos dos fármacos , Fenantridinas/farmacologia , Placenta/efeitos dos fármacos , Placenta/fisiologia , Gravidez , Espécies Reativas de Oxigênio/metabolismo , Veias Umbilicais , alfa-Tocoferol/farmacologiaRESUMO
OBJECTIVE: Hyperglycemia-induced endothelial cell dysfunction in vascular disease can occur due to increased oxidative stress and a concomitant increase in endoplasmic reticulum (ER) stress. To investigate whether these cellular stresses are independent or causally linked, we determined whether or not specific glycolytic intermediates that induce oxidative stress also induce ER stress. METHODS: Human umbilical vein endothelial cells were treated with dextrose, partially metabolizable (e.g., fructose and galactose) and non-metabolizable sugars (e.g., 3-O-methyglucose), and various intermediates of the glycolytic and tricarboxylic acid pathways. Activation of the unfolded protein response and subsequent generation of ER stress was measured by the ER stress-responsive alkaline phosphatase method, and superoxide (SO) generation was measured using the hydro-ethidene-fluorescence method. The mitochondrial origin of the SO and the generation of ER stress by dextrose and the intermediate metabolites were confirmed with experiments using allopurinol and diphenyleneiodonium chloride to block SO generation by xanthine oxidase and nicotinamide adenosine dinucleotide phosphate oxidase, respectively. RESULTS: Although ER stress could be induced by glycolytic intermediates up to and including pyruvate, the SO generation occurred in the presence of glycolytic and mitochondrial metabolites. CONCLUSION: Although the mitochondria are the site of signals generated by dextrose to initiate oxidative stress, the dextrose-induced ER stress, unlike SO generation, does not require pyruvate oxidation in the mitochondria.
Assuntos
Retículo Endoplasmático/metabolismo , Endotélio Vascular/metabolismo , Glucose/efeitos adversos , Hiperglicemia/fisiopatologia , Estresse Oxidativo , 3-O-Metilglucose/efeitos adversos , Fosfatase Alcalina/metabolismo , Células Cultivadas , Ciclo do Ácido Cítrico , Retículo Endoplasmático/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas Ligadas por GPI/metabolismo , Glucose/metabolismo , Glicólise , Hexoses/efeitos adversos , Humanos , Mitocôndrias/efeitos dos fármacos , NADPH Oxidases/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Superóxidos/metabolismo , Resposta a Proteínas não Dobradas , Xantina Oxidase/antagonistas & inibidoresRESUMO
OBJECTIVE: Current criteria for the diagnosis of diabetic ketoacidosis (DKA) are limited by their nonspecificity (serum bicarbonate [HCO(3)] and pH) and qualitative nature (the presence of ketonemia/ketonuria). The present study was undertaken to determine whether quantitative measurement of a ketone body anion could be used to diagnose DKA. RESEARCH DESIGN AND METHODS: A retrospective review of records from hospitalized diabetic patients was undertaken to determine the concentration of serum beta-hydroxybutyrate (betaOHB) that corresponds to a HCO(3) level of 18 mEq/l, the threshold value for diagnosis in recently published consensus criteria. Simultaneous admission betaOHB and HCO(3) values were recorded from 466 encounters, 129 in children and 337 in adults. RESULTS: A HCO(3) level of 18 mEq/l corresponded with betaOHB levels of 3.0 and 3.8 mmol/l in children and adults, respectively. With the use of these threshold betaOHB values to define DKA, there was substantial discordance (approximately > or = 20%) between betaOHB and conventional diagnostic criteria using HCO(3), pH, and glucose. In patients with DKA, there was no correlation between HCO(3) and glucose levels on admission and a significant but weak correlation between betaOHB and glucose levels (P < 0.001). CONCLUSIONS: Where available, serum betaOHB levels > or = 3.0 and > or = 3.8 mmol/l in children and adults, respectively, in the presence of uncontrolled diabetes can be used to diagnose DKA and may be superior to the serum HCO(3) level for that purpose. The marked variability in the relationship between betaOHB and HCO(3) is probably due to the presence of other acid-base disturbances, especially hyperchloremic, nonanion gap acidosis.