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The combined harmful effects of cigarette smoking and hyperglycemia can accelerate vascular damage in patients with diabetes who smoke, as is well known. Can smoking cause diabetes? What are the effects of smoking on macro and microvascular complications? Now growing evidence indicates that regular smokers are at risk of developing incident diabetes. Since the prevalence rates of smoking in patients with diabetes are relatively similar to those of the general population, it is essential to address the main modifiable risk factor of smoking to prevent the onset of diabetes and delay the development of its complications. Quitting smoking shows clear benefits in terms of reducing or slowing the risk of cardiovascular morbidity and mortality in people with diabetes. Does quitting smoking decrease the incidence of diabetes and its progression? What are the effects of quitting smoking on complications? The current evidence does not seem to unequivocally suggest a positive role for quitting in patients with diabetes. Quitting smoking has also been shown to have a negative impact on body weight, glycemic control and subsequent increased risk of new-onset diabetes. Moreover, its role on microvascular complications of the disease is unclear. What are the current smoking cessation treatments, and which ones are better for patients with diabetes? Stopping smoking may be of value for diabetes prevention and management of the disease and its macrovascular and microvascular complications. Unfortunately, achieving long-lasting abstinence is not easy and novel approaches for managing these patients are needed. This narrative review examines the evidence on the impact of smoking and smoking cessation in patients with diabetes and particularly in type 2 diabetes mellitus and its complications. In addition, management options and potential future directions will be discussed.
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Until recently, in Italy, the use of continuous glucose monitoring (CGM) systems has been limited, but is now rapidly increasing, including the so-called real-time CGM (rtCGM) and the intermittently viewed CGM (iCGM), also called Flash Glucose Monitoring (FGM). These technologies overcome many of the limitations of self-monitoring of blood glucose (SMBG) by fingerprick and allow to go beyond HbA1c to check glucose control in diabetes. However, standardized protocols for applying and interpreting rtCGM and FGM data are lacking. In this paper, we delineate a consensus amongst Italian diabetes physicians on the attributes of rtCGM and FGM technologies, and introduce a consistent approach for their use by Italian healthcare professionals. Most experts consider rtCGM and FGM as two separate categories of interstitial subcutaneous fluid (ISF) sensing technologies, and see them as superior to SMBG. Furthermore, there is strong consensus that rtCGM and FGM reduce hypoglycemia risk, increase the amount of time in the target glucose range and augment treatment satisfaction. However, there is still no agreement on the indication of the FGM for subjects who suffer asymptomatic hypoglycemia. Consensus on the role of education in initiating and optimizing use of rtCGM/FGM and about the interpretation of glucose trends was near unanimous, whereas no consensus was reached on the statement that there are no disadvantages/risks of rtCGM/FGM. Some issues remain in rtCGM/FGM management: a) risk of excessive correction of high or low glucose; b) risk of alert fatigue leading to alert silencing or rtCGM termination; c) allergic reaction to the adhesive keeping rtCGM or FGM sensors in place. The panel almost unanimously agreed that sensor accuracy depends on multiple variables, that alarm setting should be individualized, and that global glycemic profile represent an useful tool in interpreting glucose data. More clinical studies and a wider use of these devices will increase the efficacy and effectiveness of continuous glucose monitoring in Italy.
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Técnicas Biosensibles/instrumentación , Automonitorización de la Glucosa Sanguínea/instrumentación , Glucemia/metabolismo , Diabetes Mellitus/diagnóstico , Líquido Extracelular/metabolismo , Dispositivos Electrónicos Vestibles , Biomarcadores/sangre , Glucemia/efectos de los fármacos , Consenso , Técnica Delphi , Diabetes Mellitus/sangre , Diabetes Mellitus/tratamiento farmacológico , Diseño de Equipo , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Italia , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND AND AIMS: Metabolic syndrome (MetS) is currently considered to raise the risk for type 2 diabetes and cardiovascular events. It has been suggested that part of this risk excess may be due to a cluster of additional factors associated with MetS. We aimed to investigate the role of inflammation on the ventricular-vascular coupling in patients with MetS. METHODS AND RESULTS: We enrolled a total of 227 hypertensive patients (106 with MetS and 121 without MetS) matched for age and gender. Aortic pulse wave velocity (aPWV), intima-media thickness (IMT) and high sensitivity C-reactive protein (CRP) increased according to the number of MetS components. Patients with MetS showed increased aPWV (11.5 ± 3.7 vs. 10.3 ± 2.5 m/s, P = 0.03) compared with controls. In a model adjusted for age, sex, heart rate and mean blood pressure, aPWV resulted increased in patients with CKD (beta 1.29 m/s, 95%CI 0.61-1.96 m/s, P < 0.001) and MetS (beta 0.89 m/s, 95%CI 0.28-1.51 m/s, P = 0.005). After additional adjustment for CRP and IMT, the slope of aPWV was respectively reduced by 16% and 62%, suggesting that inflammation and intima-media thickening could contribute to aortic stiffening in patients with MetS. In these patients, aPWV was also associated with left-ventricular mass index (beta 0.79 g/m2.7, 95%CI 0.05-1.52 g/m2.7, P = 0.05). CONCLUSION: MetS is characterized by an inflammation-dependent acceleration in cardiovascular ageing. This pattern of pathophysiological abnormalities may contribute to amplify the burden of cardiovascular risk in patients with MetS.
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Hemodinámica , Hipertensión/fisiopatología , Inflamación/fisiopatología , Síndrome Metabólico/fisiopatología , Función Ventricular Izquierda , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Hipertensión/sangre , Hipertensión/diagnóstico , Inflamación/sangre , Inflamación/diagnóstico , Mediadores de Inflamación/sangre , Italia , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/diagnóstico , Pronóstico , Medición de Riesgo , Factores de Riesgo , Rigidez Vascular , Remodelación VentricularRESUMEN
Type 2 diabetes prevalence is high in older adults and is expected to rise in the next decades. Diabetes in the population of frail older adults is accompanied by functional disability, several comorbidities, and premature mortality. A comprehensive geriatric assessment, including functional, cognitive, mental and social status, is advisable for identifying the glycemic targets and glucose-lowering therapies, focused on patient preferences, needs, and risks. The therapeutic options for older adults with diabetes are like those for the adult population. However, the pharmacological treatments must be carefully prescribed and monitored, taking into consideration the patient cognitive capacities, the potentially life-threatening drug-drug interactions, the cardiovascular risk, and with the main goal of avoiding hypoglycemia. Also, a careful nutritional evaluation with appropriate tools, as well as a balanced and periodically monitored physical activity, contribute to an effective tailored care plan, as needed by older adults with diabetes. This review evaluates the currently available hypoglycemic drugs and the current indications to the Italian diabetology community, specifically with regard to the treatment of adults aged 75 years or older with diabetes, including the unmet needs by the guidelines.
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Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Atención Dirigida al Paciente , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/psicología , Biomarcadores/sangre , Glucemia/metabolismo , Toma de Decisiones Clínicas , Cognición , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/psicología , Interacciones Farmacológicas , Femenino , Evaluación Geriátrica , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemiantes/efectos adversos , Italia , Masculino , Salud Mental , Estado Nutricional , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is underdiagnosed and public cholesterol screening may be useful to find new subjects. In this study, we aim to investigate the prevalence of FH patients in a hospital screening program and evaluate their atherosclerotic burden using intima-media thickness (IMT). METHODS AND RESULTS: We screened 1575 lipid profiles and included for genetic analysis adults with a low-density lipoprotein (LDL) cholesterol >190 mg/dL and triglycerides <200 mg/dL and first-degree child relatives with LDL cholesterol >160 mg/dL and triglycerides <200 mg/dL. The diagnosis of FH was presumed by Dutch Lipid Clinic Network (DLCN) criteria and confirmed by the presence of the genetic variant. Mean common carotid intima-media thickness (IMT) was assessed using consensus criteria. After confirming LDL cholesterol value and excluding secondary hypercholesterolemia, 56 subjects with a DLCN ≥4 performed genetic analysis. Of these, 26 had an FH genetic variant. The proportion of patients with a mutation having a DLCN score of 6-8 was 75%; in individuals with a DLCN score >8 it was 100%. Mean IMT was higher in FH patients compared to non FH (0.73 [0.61-0.83] vs 0.71 [0.60-0.75] mm, p < 0.01). Moreover, we detected two mutations not previously described. Finally, simple regression analysis showed a correlation of IMT with LDL cholesterol >190 mg/dL and corneal arcus (p < 0.01 and p < 0.001, respectively). CONCLUSIONS: A hospital screening was useful to detect FH subjects with increased atherosclerosis. Also, next-generation sequencing was able to detect new FH mutations.
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Enfermedades de las Arterias Carótidas/diagnóstico , Arteria Carótida Común/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Análisis Mutacional de ADN/métodos , Hospitales , Hiperlipoproteinemia Tipo II/diagnóstico , Lípidos/sangre , Tamizaje Masivo/métodos , Mutación , Anciano , Biomarcadores/sangre , Enfermedades de las Arterias Carótidas/sangre , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedades de las Arterias Carótidas/genética , Femenino , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hiperlipoproteinemia Tipo II/sangre , Hiperlipoproteinemia Tipo II/epidemiología , Hiperlipoproteinemia Tipo II/genética , Italia/epidemiología , Masculino , Persona de Mediana Edad , Fenotipo , Placa Aterosclerótica , Valor Predictivo de las Pruebas , Prevalencia , Evaluación de Programas y Proyectos de Salud , Factores de RiesgoAsunto(s)
Control de Enfermedades Transmisibles , Consenso , Diabetes Mellitus , Comunicación Interdisciplinaria , Vacunación , Adulto , Vacuna contra Difteria, Tétanos y Tos Ferina , Herpes Zóster/prevención & control , Humanos , Vacunas contra la Influenza , Vacunas Meningococicas , Neumonía/prevención & controlRESUMEN
BACKGROUND AND AIMS: Modern diets are high in advanced glycation end-products (dAGEs), derived from processing methods, exerting a pivotal role in promoting atherosclerotic risk. In this cross-sectional study we investigate the relationship between dAGE intake, arterial stiffness, inflammatory profile and macronutrient composition, in subjects with type 2 diabetes without overt cardiovascular disease. METHODS AND RESULTS: Arterial stiffness, carboxy-methyl-lysine, endogenous secretory receptor for AGEs (esRAGE), high sensitivity C reactive protein (hs-CRP), S100A12 and macronutrient intake were evaluated in 85 subjects with type 2 diabetes. The subjects were stratified into two groups according to dAGE consumption: high and low dAGE intake (≥ or <15.000 kU/day, respectively). Subjects with high dAGE intake (n = 45) showed a higher augmentation, augmentation index and pulse wave velocity (PWV) compared with those subjects with low dAGE intake (18 ± 5.4 vs 12.2 ± 6.3 mmHg, P < 0.05; 38.3 ± 5.4 vs 29.3 ± 10%; 9.2 ± 1.4 m/sec vs 7.9 ± 1.7, P < 0.05, respectively). hs-CRP were higher in subjects with high dAGE intake [0.42 (0.18-0.54) vs 0.21 (0.14-0.52) mg/dL, P < 0.05] whereas esRAGE plasma levels were lower [0.16 (0.23-0.81) vs 0.2 (0.14-0.54) ng/dL, P < 0.05]. Simple regression analysis showed a correlation between dAGEs and fat intake. Multivariate analysis showed an independent association between augmentation, systolic blood pressure (BP) and dAGE consumption; BMI and esRAGE were the major determinants of PWV. CONCLUSIONS: Our data suggests that a chronic high dAGE diet could lead to a vascular dysfunction and inflammatory activation, contributing to the development of vascular complications in subjects with type 2 diabetes. Testing this hypothesis may represent a direction of future research.
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Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/etiología , Dieta/efectos adversos , Productos Finales de Glicación Avanzada/efectos adversos , Inflamación/etiología , Rigidez Vascular , Adulto , Anciano , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Grosor Intima-Media Carotídeo , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/diagnóstico , Angiopatías Diabéticas/fisiopatología , Femenino , Productos Finales de Glicación Avanzada/administración & dosificación , Humanos , Inflamación/sangre , Inflamación/diagnóstico , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso , Receptor para Productos Finales de Glicación Avanzada/sangre , Medición de Riesgo , Factores de RiesgoRESUMEN
INTRODUCTION: The present review developed a clinical consensus based on a Delphi method on Dapagliflozin, a selective inhibitor of the renal sodium-glucose co-transporter-2 (SGLT2-I) in the treatment of patients with Type 2 diabetes mellitus. Areas covered: Panel members, using a 5-point scale, were asked to rate 9 statements on pharmakodinamic, mode of action on glycaemic and extra-glycaemic effects, and safety of dapaglifozin, Members also aimed to identify the patient most susceptible to the treatment with dapagliflozin . Expert commentary: Dapagliflozin is effective in lowering the plasma glucose concentration with a good safety profile. Dapagliflozin can be utilized in combination with all other antihyperglycaemic agents at all stages of the disease: however, a reduced GFR limits its efficacy. As for the other drugs of the class, Dapagliflozin positively modifies other risk factors for CV disease: these effects will be tested in the so far largest cardiovascular outcome trial for the SGLT2 inhibitors so far, the DECLARE trial, which will communicate whether this class of drugs will be disease-modifier in patients with type 2 diabetes also in primary prevention.
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Compuestos de Bencidrilo/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucósidos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Compuestos de Bencidrilo/efectos adversos , Compuestos de Bencidrilo/farmacología , Glucemia/efectos de los fármacos , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Consenso , Técnica Delphi , Diabetes Mellitus Tipo 2/fisiopatología , Tasa de Filtración Glomerular , Glucósidos/efectos adversos , Glucósidos/farmacología , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/farmacología , Factores de Riesgo , Inhibidores del Cotransportador de Sodio-Glucosa 2RESUMEN
BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) represents the most common chronic liver disease in industrialized countries. NAFLD has the potential to progress through the inflammatory phase of nonalcoholic steatohepatitis (NASH) to fibrosis, cirrhosis, and hepatocellular carcinoma. Identifying patients at risk for this transition is a relevant clinical challenge. The complexity of these phenotypes in vivo made necessary the development of in vitro models in order to dissect the molecular signalling affected in NAFLD and NASH, but also to identify potential circulating biomarkers. METHODS AND RESULTS: We profiled the expression of 754 cellular and medium-secreted human miRNAs in HepG2 cells after lipotoxic (Palmitate, model of NASH) or not-lipotoxic stimuli (Oleate-Palmitate, model of NAFLD). Results were validated through Single TaqMan assays. We performed computational analysis of miRNA targets and pathways. Oleate-palmitate treatment induced a variation of 2.8% and 10% of total miRNAs in cells and medium, respectively; palmitate treatment caused 10% and 19% intracellular and extracellular miRNA deregulation, respectively. We validated miR-126, miR-150, miR-223, miR-483-3p, miR-1226*, and miR-1290 deregulation. Through computational analysis, we observed that targets of both intracellular and extracellular DE miRNAs were involved in processes associated with the onset and progression of NAFLD and NASH, such as fatty acid metabolism, apoptosis and inflammation. CONCLUSIONS: These data would be useful to elucidate the role of miRNAs in the pathogenesis and progression of the NAFLD spectrum, but they also allow the identification of novel potential biomarkers for differential diagnosis to be tested in vivo.
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Hepatocitos/metabolismo , Hígado/metabolismo , MicroARNs/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Antígenos CD36/genética , Antígenos CD36/metabolismo , Supervivencia Celular , Ceramidas/metabolismo , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Biología Computacional , Diglicéridos/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Marcadores Genéticos , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Proteínas Sustrato del Receptor de Insulina/genética , Proteínas Sustrato del Receptor de Insulina/metabolismo , Hígado/efectos de los fármacos , Hígado/patología , MicroARNs/metabolismo , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Ácido Oléico/toxicidad , Análisis de Secuencia por Matrices de Oligonucleótidos , Ácido Palmítico/toxicidad , Fosforilación , Mapas de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Factores de TiempoRESUMEN
BACKGROUND AND AIMS: We aimed to investigate lipid abnormalities and liver steatosis in patients with HbA1c-defined prediabetes and type 2 diabetes compared to individuals with HbA1c-defined normoglycaemia. METHODS AND RESULTS: Ninety-one subjects with prediabetes according to HbA1c, i.e. from 5.7 to 6.4% (39-46 mmol/mol), 50 newly diagnosed patients with HbA1c-defined type 2 diabetes (HbA1c ≥6.5% [≥48 mmol/mol]), and 67 controls with HbA1c lower than 5.7% (<39 mmol/mol), were studied. Fasting blood samples for lipid profiles, fatty liver index (FLI), bioimpedance analysis, ultrasound scan of the liver, and BARD (body mass index, aspartate aminotransferase/alanine aminotransferase ratio, diabetes) score for evaluation of liver fibrosis, were performed in all subjects. In comparison to controls, subjects with prediabetes were characterised by: lower apolipoprotein AI and HDL cholesterol levels, higher blood pressure, triglycerides levels and apolipoprotein B/apolipoprotein AI ratio, higher FLI, increased prevalence of and more severe hepatic steatosis, similar BARD score, and higher total body fat mass. In comparison to subjects with diabetes, subjects with prediabetes exhibited: similar blood pressure and apolipoprotein B/apolipoprotein AI ratio, similar FLI, reduced prevalence of and less severe hepatic steatosis, lower BARD score, increased percent fat and lower total body muscle mass. In comparison to controls, subjects with diabetes showed: lower apolipoprotein AI and HDL cholesterol levels, higher blood pressure and triglycerides levels, higher FLI, increased prevalence of and more severe hepatic steatosis, higher BARD score, and higher total body muscle mass. Moreover, HbA1c was correlated with BMI, HOMA-IR, triglycerides, HDL cholesterol, AST, and ALT. CONCLUSIONS: Subjects with HbA1c-defined prediabetes and type 2 diabetes, respectively, are characterised by abnormalities in lipid profile and liver steatosis, thus exhibiting a severe risk profile for cardiovascular and liver diseases.
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Diabetes Mellitus Tipo 2/complicaciones , Dislipidemias/epidemiología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Estado Prediabético/complicaciones , Adulto , Apolipoproteína A-I/sangre , Composición Corporal , HDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Angiopatías Diabéticas/epidemiología , Dislipidemias/complicaciones , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Resistencia a la Insulina , Italia/epidemiología , Lípidos/sangre , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Estado Prediabético/sangre , Estado Prediabético/diagnóstico , Estado Prediabético/metabolismo , Prevalencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , UltrasonografíaRESUMEN
AIM: We have explored whether the insulin secretory defects induced by glucotoxicity in human pancreatic islets could be prevented by metformin and investigated some of the possible mechanisms involved. METHODS: Human pancreatic islets and INS-1E cells were cultured for 24h with or without high glucose (16.7mM) concentration in the presence or absence of therapeutical concentration of metformin and then glucose-stimulated insulin release, adenine nucleotide levels and mitochondrial complex I and II activities were measured. Islet ultrastructure was analyzed by electron microscopy. RESULTS: Compared to control islets, human islets cultured with high glucose showed a reduced glucose-stimulated insulin secretion that was associated with lower ATP levels and a lower ATP/ADP ratio. These functional and biochemical defects were significantly prevented by the presence of metformin in the culture medium, that was also able to significantly inhibit the activity of mitochondrial complex I especially in beta cells exposed to high glucose. Ultrastructural observations showed that mitochondrial volume density was significantly increased in high glucose cultured islets. The critical involvement of mitochondria was further supported by the observation of remarkably swollen organelles with dispersed matrix and fragmented cristae. Metformin was able to efficiently prevent the appearance of all these ultrastructural alterations in human islets exposed to high glucose. CONCLUSIONS: Our results show that the functional, biochemical and ultrastructural abnormalities observed in human islet cells exposed to glucotoxic condition can be significantly prevented by metformin, further highlighting a direct beneficial effect of this drug on the insulin secreting human pancreatic beta cells.
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Diabetes Mellitus/prevención & control , Glucosa/efectos adversos , Hipoglucemiantes/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Insulina/metabolismo , Metformina/farmacología , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Células Cultivadas , Diabetes Mellitus/sangre , Diabetes Mellitus/patología , Femenino , Humanos , Secreción de Insulina , Células Secretoras de Insulina/ultraestructura , Masculino , Microscopía Electrónica , Persona de Mediana EdadRESUMEN
AIMS/HYPOTHESIS: Glucagon-like peptide 1 (GLP-1) is a major incretin, mainly produced by the intestinal L cells, with beneficial actions on pancreatic beta cells. However, while in vivo only very small amounts of GLP-1 reach the pancreas in bioactive form, some observations indicate that GLP-1 may also be produced in the islets. We performed comprehensive morphological, functional and molecular studies to evaluate the presence and various features of a local GLP-1 system in human pancreatic islet cells, including those from type 2 diabetic patients. METHODS: The presence of insulin, glucagon, GLP-1, proconvertase (PC) 1/3 and PC2 was determined in human pancreas by immunohistochemistry with confocal microscopy. Islets were isolated from non-diabetic and type 2 diabetic donors. GLP-1 protein abundance was evaluated by immunoblotting and matrix-assisted laser desorption-ionisation-time of flight (MALDI-TOF) mass spectrometry. Single alpha and beta cell suspensions were obtained by enzymatic dissociation and FACS sorting. Glucagon and GLP-1 release were measured in response to nutrients. RESULTS: Confocal microscopy showed the presence of GLP-1-like and PC1/3 immunoreactivity in subsets of alpha cells, whereas GLP-1 was not observed in beta cells. The presence of GLP-1 in isolated islets was confirmed by immunoblotting, followed by mass spectrometry. Isolated islets and alpha (but not beta) cell fractions released GLP-1, which was regulated by glucose and arginine. PC1/3 (also known as PCSK1) gene expression was shown in alpha cells. GLP-1 release was significantly higher from type 2 diabetic than from non-diabetic isolated islets. CONCLUSIONS/INTERPRETATION: We have shown the presence of a functionally competent GLP-1 system in human pancreatic islets, which resides in alpha cells and might be modulated by type 2 diabetes.
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Diabetes Mellitus Tipo 2/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Células Secretoras de Glucagón/metabolismo , Glucagón/metabolismo , Insulina/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Páncreas/metabolismoRESUMEN
OBJECTIVE: We investigated the separate impact of metabolic syndrome (MS) and altered glucose tolerance on early markers of vascular injuries. METHODS: Intima-media thickness (IMT) and pulse wave analysis (PWA), were evaluated in 132 overweight or obese subjects, with (MS(+)) or without (MS(-)) MS; subjects were further classified as normotolerant (NT) or with altered glucose tolerance (AGT) according to a 2 h oral glucose tolerance test (OGTT). RESULTS: In MS(+) patients, IMT was higher than in the MS(-) group, and PWA revealed higher augmentation pressure (Aug, the contribution that wave reflection makes to systolic arterial pressure) and lower subendocardial viability ratio (SEVR, an estimate of myocardial perfusion). When analyzed according to glucose tolerance, IMT was higher in MS(+)NT subjects and AGT patients with and without MS, vs. MS(-)NT subjects. Logistic regression modeling showed that both AGT and MS were independently associated with increased IMT. However, only MS remained associated with IMT after adjustment for age. SEVR was reduced only in MS(+) patients, independently of glucose tolerance. In both groups, Aug and AugI were higher in the AGT group, but the correlation with 2 h-plasma glucose disappeared when corrected for age. CONCLUSION: Both MS and AGT altered IMT, but the effect of AGT disappears when age is added to the multiple regression model. In contrast, arterial stiffness was affected differently in the two categories: in subjects with MS, the subendocardial viability ratio (an estimate of myocardial perfusion) was impaired, while in subjects with AGT, both Aug and AugI were increased. These data suggest that applying the definition of MS might help to better characterize cardiovascular risk in subjects with altered glucose tolerance or obesity.
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Enfermedades de las Arterias Carótidas/epidemiología , Trastornos del Metabolismo de la Glucosa/epidemiología , Síndrome Metabólico/epidemiología , Adulto , Factores de Edad , Biomarcadores/sangre , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/sangre , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/fisiopatología , Grosor Intima-Media Carotídeo , Distribución de Chi-Cuadrado , Diagnóstico Precoz , Femenino , Trastornos del Metabolismo de la Glucosa/sangre , Trastornos del Metabolismo de la Glucosa/diagnóstico , Prueba de Tolerancia a la Glucosa , Hemodinámica , Humanos , Italia/epidemiología , Modelos Logísticos , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/diagnóstico , Persona de Mediana Edad , Análisis Multivariante , Obesidad/epidemiología , Oportunidad Relativa , Valor Predictivo de las Pruebas , Análisis de la Onda del Pulso , Medición de Riesgo , Factores de Riesgo , Rigidez VascularRESUMEN
BACKGROUND: In rat pancreatic islets, chronic exposure to high free fatty acid (FFA) levels impairs insulin secretion and ß cell mass. The mechanisms underlying this defect are not completely understood. Since islets have intrinsically low anti-oxidant enzyme defense, oxidative stress might be responsible for ß cell damage. AIM: In this study, we investigated if FFA could induce oxidative stress in rat pancreatic islets and if metformin might reverse adverse effects. MATERIAL AND METHODS: We cultured rat pancreatic islets in the presence or absence of FFA (oleate/palmitate 2:1, 2 mM) for 72 h. In some experiments, we used metformin (2.5 µg/ml) during the last 24 h. RESULTS: In our model, glucosestimu lated insulin release was markedly reduced (p<0.005) after chronic FFA exposure, and the ATP/ADP ratio was altered (p<0.05). We observed a significant increase of reactive oxygen species (ROS) (p<0.001), malondialdehyde a lipid peroxidation product (p<0.01) and nitric oxide (NO) levels in the culture media (p<0.001). Inducible NO synthase (iNOS) and heat shock protein-70 (HSP-70) protein expression were also increased (p<0.001 and p<0.01, respectively). When metformin was present during the last 24 h of culture, insulin secretion was restored, and the ATP/ADP ratio was normalized. ROS production, NO production, lipid peroxidation, iNOS and HSP-70 protein expression levels had decreased. CONCLUSIONS: These data indicate that, in rat pancreatic islets, chronic exposure to high FFA induces oxidative stress and that metformin, by reducing this effect, may have a direct beneficial effect on insulin secretion impaired by lipotoxicity.
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Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Ácidos Grasos no Esterificados/efectos adversos , Glucosa/farmacología , Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Metformina/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Supervivencia Celular/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/metabolismo , Hipoglucemiantes/farmacología , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Masculino , Malondialdehído/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Nitritos/metabolismo , Ratas , Ratas WistarRESUMEN
BACKGROUND AND AIMS: Metabolic syndrome (MS) has been mainly related to insulin resistance, but the role of changes in insulin secretion has not been thoroughly investigated. METHODS AND RESULTS: Using an oral glucose tolerance test (OGTT) we studied beta-cell function and insulin sensitivity in subjects with normal fasting glucose with and without MS, and their relationship to fatty liver which was evaluated by abdominal-ultrasonography. In MS early phase insulin secretion, as measured by insulinogenic index (IG(30)), was increased (p<0.05) independently from insulin sensitivity. Furthermore IG(30) was progressively higher as the number of factors needed for the diagnosis of MS increased (p<0.01). Insulin and C-peptide AUC were also increased (p<0.01 and p<0.05, respectively) but, in contrast to IG(30), these differences disappeared when ISI was used as a covariate. After OGTT, 51% of the subjects with MS had altered post-load glucose tolerance compared to 24.9% without MS (p<0.01). In both groups, the altered glucose tolerance was associated with a similar IG(30) reduction. In normo-tolerant subjects with MS the IG(30) was higher (+54.1%, p<0.01), and this elevation occurred irrespective of ISI; however, the beta-cell compensatory capacity for insulin resistance (disposition index) was impaired (p<0.001). Fatty liver was more frequent (p<0.001) and more severe (p<0.01) in MS, and it was significantly related to total AUC-insulin (p<0.001), independently from ISI. CONCLUSION: These findings indicate that the prevalence of altered tolerance is more frequent in subjects with normal fasting glucose and MS. The hyperinsulinemia might not only be an adaptive response to insulin resistance, but a primary defect of beta-cell function contributing to glucose intolerance.
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Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Síndrome Metabólico/metabolismo , Síndrome Metabólico/fisiopatología , Estado Prediabético/metabolismo , Estado Prediabético/fisiopatología , Adulto , Algoritmos , Glucemia/análisis , Proteína C-Reactiva/análisis , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etiología , Hígado Graso/diagnóstico por imagen , Hígado Graso/epidemiología , Hígado Graso/etiología , Femenino , Intolerancia a la Glucosa/epidemiología , Intolerancia a la Glucosa/etiología , Humanos , Hiperinsulinismo/epidemiología , Hiperinsulinismo/etiología , Insulina/sangre , Resistencia a la Insulina , Secreción de Insulina , Cinética , Masculino , Síndrome Metabólico/sangre , Persona de Mediana Edad , Estado Prediabético/sangre , Prevalencia , Índice de Severidad de la Enfermedad , UltrasonografíaRESUMEN
Glycemic control in elderly persons with type 2 diabetes mellitus (T2DM) is challenging because they are more likely to have other age-associated medical conditions and to experience hypoglycemia during intensive therapy. A best therapeutic strategy for these patients has not yet been defined. We investigated the efficacy and safety of adding once-daily insulin glargine to patients' current oral antidiabetic drugs (OAD) regimen, compared to increasing the OAD doses. The study enrolled patients aged 65 years or more, with poor glycemic control. Patients were randomized to two groups and entered a 3-week titration period in which their actual therapy was adjusted to meet the study's glycemic goals, by either adding insulin glargine to current therapy (group A, 27 patients) or increasing current OAD dosages (group B, 28 patients). Thereafter, therapies were continued unchanged for a 24-week observation period. The mean therapeutic dosage of insulin glargine in group A was 14.9 IU/day (SD = 5.0 IU/day). During the observation period, mean levels of glycosylated hemoglobin (HbA1c) reduced by 1.5% in group A and 0.6% in group B (P = 0.381). An HbA1c level <7.0% was achieved by five patients in each group. Mean fasting blood glucose levels reduced by 29 and 15% in groups A and B, respectively (P = 0.029). Group A had fewer total hypoglycemic events (23 vs. 79, P = 0.030) and fewer patients experiencing any such event (9 vs. 17, P = 0.045). Neither a serious hypoglycemic event nor other adverse event occurred. These results suggest that, compared to increasing OAD dosage, the addition of insulin glargine to current OAD therapy is as effective but safer in terms of the risk for hypoglycemia in elderly patients with T2DM.
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Glucemia/metabolismo , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Insulina/análogos & derivados , Administración Oral , Anciano , Índice de Masa Corporal , Carbamatos/uso terapéutico , Quimioterapia Combinada , Femenino , Gliclazida/uso terapéutico , Hemoglobina Glucada/metabolismo , Humanos , Insulina/uso terapéutico , Insulina Glargina , Insulina de Acción Prolongada , Masculino , Metformina/uso terapéutico , Pioglitazona , Piperidinas/uso terapéutico , Proyectos de Investigación , Rosiglitazona , Tiazolidinedionas/uso terapéuticoRESUMEN
BACKGROUND: Long-chain polyunsaturated fatty acid omega-3 levels are decreased in the hepatic tissue of patients with nonalcoholic fatty liver disease. Polyunsaturated fatty acids are negative regulators of hepatic lipogenesis and attenuate the inflammatory response in mice. AIM: To investigate whether polyunsaturated fatty acid may be effective in the treatment of nonalcoholic fatty liver disease. METHODS: Forty patients with nonalcoholic fatty liver disease were randomized into two groups for treatment of 6 months duration. Group DP (n=20) received an AHA recommended diet and polyunsaturated fatty acid 2g/day; Group D (n=20) received only the AHA regular diet. Outcome measurements were fatty liver assessed by abdominal ultrasound, liver aminotransferase and tumour necrosis factor-alpha serum levels, and insulin resistance assessed by HOMA(IR). RESULTS: After 6 months of treatment, the DP group displayed a decrease in alanine aminotransferase levels (p<0.01), as well as in triglyceride levels (p<0.01), serum tumour necrosis factor-alpha levels (p<0.05) and in HOMA(IR) (p<0.05). In the D group, no significant modification was observed. In the DP group, complete fatty liver regression was observed in 33.4% of the patients, and an overall reduction in 50%. In contrast, no patient achieved complete regression in the D group, whereas some amount of reduction occurred in 27.7% of the patients; the remaining 72.2% did not change. CONCLUSION: Our results indicate that alanine aminotransferase, triglyceride and serum tumour necrosis factor-alpha levels, as well as fatty liver improved after polyunsaturated fatty acid administration.
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Ácidos Grasos Omega-3/uso terapéutico , Hígado Graso/dietoterapia , Hígado Graso/diagnóstico por imagen , Hígado Graso/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Resistencia a la Insulina/fisiología , Lipogénesis/efectos de los fármacos , Hígado/diagnóstico por imagen , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Transaminasas/metabolismo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/sangre , UltrasonografíaRESUMEN
UNLABELLED: Osteoporosis has been associated with cardiovascular disease. We found increased augmentation index, a measure of wave reflections and arterial stiffness, and central pressures in osteoporotic postmenopausal women. They also showed a higher estimated aortic pulse wave velocity, indicating a stiffer aorta. These changes may increase cardiovascular risk in postmenopausal osteoporosis. INTRODUCTION: Evidence suggests a link between osteoporosis and cardiovascular disease. We investigated whether augmentation index (AIx), a measure of pulse wave reflections and arterial stiffness, is increased and related to the osteoprotegerin (OPG)/receptor activator of nuclear factor-kappa B ligand (RANKL) system in postmenopausal osteoporosis. METHODS: AIx and central aortic haemodynamics were assessed using pulse wave analysis in 182 cardiovascular disease-free osteoporotic postmenopausal women and in 160 controls. Statistical analysis was performed by unpaired t test, Mann-Whitney test, Spearman's correlation coefficient, and multivariate linear regression analysis. RESULTS: AIx (37.2 +/- 7.0 vs. 29.6 +/- 9.2 %, P < 0.0001) and central aortic systolic (117.5 +/- 12.1 vs. 111.4 +/- 12.2 mmHg, P < 0.0001) and pulse (40.5 +/- 10.3 vs. 36.4 +/- 8.1 mmHg, P = 0.0007) pressures were significantly higher in osteoporotic patients than in controls. The estimated aortic pulse wave velocity (PWV) was also significantly higher in the osteoporotic group. In multivariate analysis for osteoporotic patients, femoral neck and lumbar spine bone mineral density T scores were independent negative predictors of AIx (P < 0.0001). AIx was not correlated with serum levels of OPG and RANKL. CONCLUSIONS: Osteoporotic postmenopausal women show increased AIx and central aortic pressures, and a higher estimated aortic PWV, indicating a stiffer aorta. Such alterations may increase cardiovascular risk in postmenopausal osteoporosis.
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Aorta/fisiopatología , Presión Sanguínea/fisiología , Osteoporosis Posmenopáusica/fisiopatología , Flujo Pulsátil/fisiología , Resistencia Vascular/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Densidad Ósea , Estudios de Casos y Controles , Femenino , Cuello Femoral/química , Humanos , Italia , Vértebras Lumbares/química , Persona de Mediana Edad , Osteoprotegerina/sangre , Ligando RANK/sangreRESUMEN
BACKGROUNDS AND AIMS: Non-alcoholic-steatohepatitis (NASH) is closely related to insulin resistance, but it is unknown whether insulin resistance may be localized in hepatocytes. This study investigates insulin signalling in liver tissue from NASH, and the molecular mechanisms by which insulin-resistance could lead to liver damage (apoptosis). Moreover, to investigate the mechanisms of lipid overload we studied key enzymes in hepatocytes lipid metabolism. METHODS AND RESULTS: In liver specimens from 11 patients with NASH and 7 histological normal livers, we measured total and phosphorylated Akt (active form), Bax and Bcl-2 by Western-blot analysis. In addition, we studied AMP-activated protein Kinase and Carnitine-Palmitoyl-Transferase-1 gene expression, key regulators of non-esterified fatty acid synthesis and oxidation, by reverse transcription polymerase chain reaction. In NASH, phosphorylated Akt was impaired (104.3+/-10.6 vs 152.6+/-22.4 AU, p<0.002) and correlated with necroinflammatory score (r=-0.62; p<0.05). Bax/Bcl-2 ratio was increased in NASH. Moreover, we observed a decrease of AMP-activated protein Kinase (10.74+/-6 vs 144.7+/-41.6 AU, p<0.0001) and Carnitine-Palmitoyl-Transferase-1 gene expression (38.7+/-14.6 vs 192.1+/-26.2 AU, p<0.0001), and both were correlated with steatosis score (r=-0.56, p<0.05, r=-0.87, p<0.05 respectively). CONCLUSIONS: Akt, a key molecule of insulin signalling and cell apoptosis is impaired in NASH, suggesting an important role of hepatic insulin resistance in liver failure. Moreover, decreased non-esterified fatty acid oxidation may cause hepatic lipid overload.