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PURPOSE: According to preclinical evidence, GLP-1 receptor may be an actionable target in neurodegenerative disorders, including Alzheimer's disease (AD). Previous clinical trials of GLP-1 receptor agonists were conducted in patients with early AD, yielding mixed results. The aim was to assess in a proof-of-concept study whether slow-release exenatide, a long-acting GLP-1 agonist, can benefit the cognitive performance of people with mild cognitive impairment (MCI). METHODS: Thirty-two (16 females) patients were randomized to either slow-release exenatide (n = 17; 2 mg s.c. once a week) or no treatment (n = 15) for 32 weeks. The primary endpoint was the change in ADAS-Cog11 cognitive test score at 32 weeks vs baseline. Secondary endpoints herein reported included additional cognitive tests and plasma readouts of GLP-1 receptor engagement. Statistical analysis was conducted by intention to treat. RESULTS: No significant between-group effects of exenatide on ADAS-Cog11 score (p = 0.17) were detected. A gender interaction with treatment was observed (p = 0.04), due to worsening of the ADAS-Cog11 score in women randomized to exenatide (p = 0.018), after correction for age, scholar level, dysglycemia, and ADAS-Cog score baseline value. Fasting plasma glucose (p = 0.02) and body weight (p = 0.03) decreased in patients randomized to exenatide. CONCLUSION: In patients with MCI, a 32-week trial with slow-release exenatide had no beneficial effect on cognitive performance. TRIAL REGISTRATION NUMBER: NCT03881371, registered on 21 July, 2016.
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We tested the hypothesis that common genetic variability of beta-cell genes responsible for monogenic diabetes may affect beta cell function in type 2 diabetes mellitus (T2DM). We studied 794 drug- naïve GAD-negative patients with newly diagnosed T2DM (age: median=59 years; I.Q. range: 52-66; body mass index: 29.3 kg/m2; 26.6-32.9). Beta-cell function was assessed by state-of-art mathematical modeling of glucose/C-peptide curves during a 240'-300' frequently sampled oral glucose tolerance test, to provide the beta-cell responses to the rate of increase in glucose concentration (derivative control: DC) and to glucose concentration (proportional control: PC). Forty-two single nucleotide polymorphism (SNPs), selected to cover over 90% of common genetic variability, were genotyped in nine monogenic diabetes genes: HNF4A, GCK, HNF1A, PDX1, HNF1B, NEUROD1, KLF11, KCNJ11 and ABCC8. Allelic variants of four SNPs (rs1303722 and rs882019 of GCK, rs7310409 of HNF1A and rs5219 of KCNJ11) were significantly associated with DC of beta-cell secretion (all P < 0.036). Allelic variants of four other SNPs (rs2868094 and rs6031544 of HNF4A, and rs1801262 and rs12053195 of NEUROD1) were associated with PC of beta-cell secretion (P < 0.02). In multivariate models, GCK, HNF1A and KCNJ11 SNPs explained 2.5% of the DC variability of beta-cell secretion, whereas HNF4A and NEUROD1 SNPs explained 3.6% of the PC variability of beta-cell secretion. We conclude that common variability of monogenic diabetes genes is significantly associated with an impaired beta-cell function in patients with newly diagnosed T2DM; thereby, these genes might be targeted by specific treatments in T2DM.
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Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Anciano , Péptido C , Glucosa , Prueba de Tolerancia a la Glucosa , Humanos , Persona de Mediana Edad , MutaciónRESUMEN
BACKGROUND: Elevated fasting plasma glucose has been associated with increased risk for development of type 2 diabetes (T2D). The balance between glucokinase (GCK) and glucose-6-phosphate catalytic subunit 2 (G6PC2) activity are involved in glucose homeostasis through glycolytic flux, and subsequent insulin secretion. AIM: In this study, we evaluated the association between the genetic variability of G6PC2 and GCK genes and T2D-related quantitative traits. METHODS: In 794 drug-naïve, GADA-negative, newly diagnosed T2D patients (VNDS; NTC01526720) we performed: genotyping of 6 independent tag-SNPs within GCK gene and 5 tag-SNPs within G6PC2 gene; euglycaemic insulin clamp to assess insulin sensitivity; OGTT to estimate beta-cell function (derivative and proportional control; DC, PC) by mathematical modeling. Genetic association analysis has been conducted using Plink software. RESULTS: Two SNPs within GCK gene (rs882019 and rs1303722) were associated to DC in opposite way (both p < 0.004). Two G6PC2 variants (rs13387347 and rs560887) were associated to both parameters of insulin secretion (DC and PC) and to fasting C-peptide levels (all p < 0.038). Moreover, subjects carrying the A allele of rs560887 showed higher values of 2h-plasma glucose (2hPG) (p = 0.033). Haplotype analysis revealed that GCK (AACAAA) haplotype was associated to decreased fasting C-peptide levels, whereas, the most frequent haplotype of G6PC2 (GGAAG) was associated with higher fasting C-peptide levels (p = 0.001), higher PC (ß = 6.87, p = 0.022) and the lower 2hPG (p = 0.012). CONCLUSION: Our findings confirmed the role of GCK and G6PC2 in regulating the pulsatility in insulin secretion thereby influencing insulin-signaling and leading to a gradual modulation in glucose levels in Italian patients with newly diagnosed T2D.
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Diabetes Mellitus Tipo 2 , Quinasas del Centro Germinal/genética , Glucosa-6-Fosfatasa/genética , Glucosa/metabolismo , Secreción de Insulina/genética , Insulina , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Glucosa-6-Fosfato/metabolismo , Haplotipos , Humanos , Insulina/biosíntesis , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/patología , Italia/epidemiología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido SimpleRESUMEN
AIMS: The Italian Titration Approach Study (ITAS) demonstrated comparable HbA1c reductions and similarly low hypoglycaemia risk at 6 months in poorly controlled, insulin-naïve adults with T2DM who initiated self- or physician-titrated insulin glargine 300 U/mL (Gla-300) in the absence of sulphonylurea/glinide. The association of patient characteristics with glycaemic and hypoglycaemic outcomes was assessed. METHODS: This post hoc analysis investigated whether baseline patient characteristics and previous antihyperglycaemic drugs were associated with HbA1c change and hypoglycaemia risk in patient- versus physician-managed Gla-300 titration. RESULTS: HbA1c change, incidence of hypoglycaemia (any type) and nocturnal rates were comparable between patient- and physician-managed arms in all subgroups. Hypoglycaemia rates across subgroups (0.03 to 3.52 events per patient-year) were generally as low as observed in the full ITAS population. Small increases in rates of 00:00-pre-breakfast and anytime hypoglycaemia were observed in the ≤ 10-year diabetes duration subgroup in the patient- versus physician-managed arm (heterogeneity of effect; p < 0.05). CONCLUSIONS: Comparably fair glycaemic control and similarly low hypoglycaemia risk were achieved in almost all patient subgroups with patient- versus physician-led Gla-300 titration. These results reinforce efficacy and safety of Gla-300 self-titration across a range of phenotypes of insulin-naïve people with T2DM. CLINICAL TRIAL REGISTRATION: EudraCT 2015-001167-39.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Cálculo de Dosificación de Drogas , Insulina Glargina/administración & dosificación , Médicos , Automanejo , Adulto , Anciano , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Estudios de Seguimiento , Control Glucémico/métodos , Control Glucémico/normas , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Incidencia , Insulina Glargina/efectos adversos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Relaciones Médico-Paciente , Médicos/normas , Médicos/estadística & datos numéricos , Estudios Retrospectivos , Automanejo/estadística & datos numéricos , Volumetría/métodos , Volumetría/normasRESUMEN
BACKGROUND AND AIMS: Fostering patient's self-managing of basal insulin therapy could improve glucose control, by removing patient's and physician's barriers to basal insulin initiation, titration and glucose monitoring. The Italian Titration Approaches Study (ITAS) aims at demonstrating non-inferiority (<0.3% margin) in efficacy of glucose control (change in glycated hemoglobin [HbA1c] after 24 weeks) by the same titration algorithm of insulin glargine 300 U/mL (Gla-300), managed by the (nurse assisted) patient versus the physician, in insulin naïve patients with Type 2 Diabetes Mellitus (T2DM), uncontrolled with previous treatments. METHODS AND RESULTS: ITAS is a phase IV, 24-week, national, multicenter, open label, randomized (1:1) parallel group study. 458 patients were enrolled, 359 randomized, and 339 completed the study, in 46 Italian centers. Baseline characteristics and previous medications of the ITT population (N = 355) are reported. Mean ± SD age, T2DM duration, HbA1c, FPG and BMI were 64.0 ± 9.8 years, 11.6 ± 7.6 years, 8.79 ± 0.65%, 170.9 ± 42.3 mg/dL, and 30.3 ± 5.6 kg/m2, respectively. Vascular and metabolic disorders were most frequent (73.8% and 58.3%, respectively). More than 90% of patients were on metformin. CONCLUSION: ITAS is the first study to compare two different managers (nurse-assisted patient vs physician) of the same titration algorithm of Gla-300 in insulin naïve patients with T2DM in unsatisfactory glucose control. This study might provide novel evidence on the efficacy/effectiveness of patient-managed titration algorithm of Gla-300 in a pragmatic setting and may reduce barriers to basal insulin initiation and its titration.
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Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Insulina Glargina/administración & dosificación , Autocuidado , Anciano , Biomarcadores/sangre , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/enfermería , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/efectos adversos , Insulina Glargina/efectos adversos , Italia , Masculino , Persona de Mediana Edad , Rol de la Enfermera , Participación del Paciente , Rol del Médico , Factores de Tiempo , Resultado del TratamientoRESUMEN
Some food/food components have been the object of request of authorization to the use of health claims related to cognitive function in adults and compliant with the Regulation (EC) 1924/2006. Most of the requests have received a negative opinion by the European Food Safety Authority (EFSA) also because of the choice of not appropriate outcome variables (OVs) and methods of measurement (MMs) selected in the trials used to substantiate the claim. This manuscript referes to the collection, collation and critical analysis of OVs and MMs related to cognitive function in adults. OVs and MMs were collected from the EFSA Guidance document and the applications for authorization of health claims pursuant to the Articles 13(5). The critical analysis of OVs and MMs, performed by a literature review, was aimed at defining their appropriateness in the context of a specific claimed effect. The results highlight the importance of an adequate choice of OVs and MMs for an effective substantiation of the claims related to cognitive functioning. The information provided in this document may serve to EFSA for updating the guidance on the scientific requirements for health claims related to cognitive functions, but also for a better design of randomized controlled trials aimed at substantiating such health claims.
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Cognición , Dieta , Alimentos , Inocuidad de los Alimentos , Humanos , Legislación de Medicamentos , Pruebas NeuropsicológicasRESUMEN
BACKGROUND AND AIM: Lifestyle is considered a major determinant of risk of type 2 diabetes (T2D). We investigated whether daily physical activity (DPA) is associated with beta-cell function (BF) and/or insulin sensitivity (IS) in patients with T2D at the time of diagnosis. METHODS AND RESULTS: In 41 subjects enrolled in the Verona Newly-Diagnosed Type 2 Diabetes Study we assessed: (1) IS, by euglycaemic insulin clamp; (2) BF, estimated by prolonged-OGTT minimal modeling and expressed as derivative and proportional control; (3) DPA and energy expenditure (EE), assessed over 48-h monitoring by a validated wearable armband system. Study participants (median [IQR]; age: 62 [53-67] years, BMI: 30.8 [26.5-34.3] Kg m-2, HbA1c: 6.7 [6.3-7.3]%; 49.7 [45.4-56.3] mmol/mol) were moderately active (footsteps/day: 7773 [5748-10,927]; DPA≥3MET: 70 [38-125] min/day), but none of them exercised above 6 metabolic equivalents (MET). EE, expressed as EETOT (total daily-EE) and EE≥3MET (EE due to DPA≥3MET) were 2398 [2226-2801] and 364 [238-617] Kcal/day, respectively. IS (M-clamp 630 [371-878] µmol/min/m2) was positively associated with DPA and EE, independent of age, sex and BMI (p < 0.05). Among the DPA and EE parameters assessed, DPA≥3MET and EETOT were independent predictors of IS in multivariable regression analyses, adjusted for age, sex, BMI (R2 = 16%, R2 = 19%, respectively; p < 0.01). None of model-derived components of BF was significantly associated with DPA or accompanying EE. CONCLUSIONS: Our study highlighted moderate levels of DPA and total EE as potential determinants of IS, but not BF, in T2D at the time of diagnosis. Intervention studies are needed to conclusively elucidate the effect of DPA on these features. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT01526720.
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Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Metabolismo Energético , Ejercicio Físico , Resistencia a la Insulina , Células Secretoras de Insulina/metabolismo , Insulina/sangre , Actigrafía/instrumentación , Anciano , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Monitores de Ejercicio , Estilo de Vida Saludable , Humanos , Italia , Masculino , Persona de Mediana Edad , Fenotipo , Factores Protectores , Factores de Riesgo , Conducta de Reducción del Riesgo , Factores de TiempoRESUMEN
BACKGROUND AND AIMS: The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006. METHODS AND RESULTS: Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects. CONCLUSIONS: The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims.
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Antioxidantes/administración & dosificación , Enfermedades Cardiovasculares/prevención & control , Inocuidad de los Alimentos , Alimentos Funcionales , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/efectos adversos , Biomarcadores/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Daño del ADN/efectos de los fármacos , Europa (Continente)/epidemiología , Alimentos Funcionales/efectos adversos , Regulación Gubernamental , Análisis de Peligros y Puntos de Control Críticos , Humanos , Legislación Alimentaria , Peroxidación de Lípido/efectos de los fármacos , Factores Protectores , Carbonilación Proteica/efectos de los fármacos , Medición de Riesgo , Factores de RiesgoRESUMEN
The quantity and quality of dietary fat and/or carbohydrate may alter one or more of the basic components of the insulin-glucose system, which in turn affect the pathways leading to alterations in glucose homeostasis and, possibly, to cardiovascular disease. This viewpoint article, reviewing some of the currently available tools aiming at quantifying the impact of dietary carbohydrates on the glucose-insulin homeostatic loop, highlights the unmet need of a more thorough assessment of the complex interaction between dietary factors and the glucose-insulin system. A novel index, the "ß-cell burden index", may turn out to be a valuable tool to quantify the role played by the diet in shaping the risk of type 2 diabetes, cardiovascular disease and other metabolic and degenerative disorders, ideally orienting their prevention with strategies based on dietary modifications.
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Enfermedades Cardiovasculares/etiología , Diabetes Mellitus Tipo 2/etiología , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/metabolismo , Células Secretoras de Insulina/metabolismo , Animales , Glucemia/metabolismo , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/patología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/prevención & control , Dieta Saludable , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/efectos adversos , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/efectos adversos , Índice Glucémico , Carga Glucémica , Humanos , Insulina/sangre , Células Secretoras de Insulina/patología , Estado Nutricional , Factores de Riesgo , Conducta de Reducción del RiesgoRESUMEN
AIMS: Diabetes treatments aim at preventing undesirable metabolic effects of hyperglycemia and at preventing/reducing tissue damage, including cardiovascular (CV) events. For approval, novel diabetes drugs undergo early systematic investigation to assess CV safety. This review provides an updated analysis of the results of recent studies examining novel diabetes medications and CV outcomes. DATA SYNTHESIS: The new regulatory guidelines enforce adjudication of all CV events when testing novel diabetes drugs. Endpoints of CV mortality, myocardial infarction (MI), stroke and hospitalization for heart failure (HF) were included in the most recent clinical studies on novel antihyperglycemics. These are: the incretin mimetics glucagon-like peptide 1 (GLP-1) receptor agonists (GLP1-RA), the incretin enhancers dipeptidylpeptidase-4 (DPP-4) inhibitors (DPP4-I or gliptins), and the sodium-glucose cotransporter (SGLT2) inhibitors (SGLT2-I or gliflozins). The studies ELIXA and EXAMINE, testing lixisenatide and alogliptin, respectively, revealed non-inferiority versus placebo in terms of CV safety. The SAVOR-TIMI 53 results confirmed overall CV safety of saxagliptin, but raised a warning related to the increase in the risk of hospitalization for HF in the saxagliptin group. Recently, TECOS revealed a particularly favorable CV profile for sitagliptin while EMPA-REG showed a significant CV risk reduction in empagliflozin treated subjects. Ongoing studies will provide additional data on CV safety for other GLP1-RAs, DPP4-I and SGLT2-I. CONCLUSIONS: Results of safety outcome studies focused on CV events, including HF and mortality for CV causes, are not homogeneous. A critical analysis of these studies may help cardiologists and diabetes specialists to adapt their therapeutic choices to individual patients.
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Compuestos de Bencidrilo/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Glucósidos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Incretinas/uso terapéutico , Fosfato de Sitagliptina/uso terapéutico , Compuestos de Bencidrilo/efectos adversos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/mortalidad , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Glucósidos/efectos adversos , Humanos , Hipoglucemiantes/efectos adversos , Incretinas/efectos adversos , Seguridad del Paciente , Selección de Paciente , Medición de Riesgo , Factores de Riesgo , Fosfato de Sitagliptina/efectos adversos , Resultado del TratamientoRESUMEN
BACKGROUND AND AIMS: Insulin resistance is a hallmark of type 2 diabetes (T2DM), it is often accompanied by defective beta-cell function (BF) and is involved in the pathophysiology of cardiovascular disease (CVD). Commonalities among these traits may recognize a genetic background, possibly involving the genetic variation of insulin signaling pathway genes. We conducted an exploratory analysis by testing whether common genetic variability at IRS1, ENPP1 and TRIB3 loci is associated with cardiovascular risk traits and metabolic phenotypes in T2DM. METHODS AND RESULTS: In 597 drug-naïve, GADA-negative, newly-diagnosed T2DM patients we performed: 1) genotyping of 10 independent single-nucleotide polymorphisms covering â¼ 90% of common variability at IRS1, ENPP1 and TRIB3 loci; 2) carotid artery ultrasound; 3) standard ECG (n = 450); 4) euglycaemic insulin clamp to assess insulin sensitivity; 5) 75 g-OGTT to estimate BF (derivative and proportional control) by mathematical modeling. False discovery rate of multiple comparisons was set at 0.20. After adjustment for age, sex and smoking status, rs4675095-T (IRS1) and rs4897549-A (ENPP1) were significantly associated with carotid atherosclerosis severity, whilst rs7265169-A (TRIB3) was associated with ECG abnormalities. Rs858340-G (ENPP1) was significantly associated with decreased insulin sensitivity, independently of age, sex and body-mass-index. No consistent relationships were found with BF. CONCLUSION: Some associations were found between intermediate phenotypes of CVD and common genetic variation of gatekeepers along the insulin signaling pathway. These results need be replicated to support the concept that in T2DM the CVD genetic risk clock may start ticking long before hyperglycemia appears. ClinicalTrials.gov Identifier: NCT01526720.
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Enfermedades Cardiovasculares/genética , Diabetes Mellitus Tipo 2/genética , Síndrome Metabólico/genética , Polimorfismo de Nucleótido Simple , Anciano , Índice de Masa Corporal , Enfermedades Cardiovasculares/complicaciones , Proteínas de Ciclo Celular/genética , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Genotipo , Técnicas de Genotipaje , Hemoglobina Glucada/metabolismo , Humanos , Proteínas Sustrato del Receptor de Insulina/genética , Resistencia a la Insulina , Modelos Logísticos , Masculino , Síndrome Metabólico/complicaciones , Persona de Mediana Edad , Hidrolasas Diéster Fosfóricas/genética , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Pirofosfatasas/genética , Proteínas Represoras/genética , Factores de Riesgo , Transducción de Señal , Circunferencia de la CinturaRESUMEN
BACKGROUND AND AIMS: The relatives role of each component of the glucose-insulin system in determining hyperglycemia in type 2 diabetes is still under debate. Metabolic Control Analysis (MCA) quantifies the control exerted by each component of a system on a variable of interest, by computing the relevant coefficients of control (CCs), which are systemic properties. We applied MCA to the intravenous glucose tolerance test (IVGTT) to quantify the CCs of the main components of the glucose-insulin system on intravenous glucose tolerance. METHODS AND RESULTS: We combined in vivo phenotyping (IVGTT/euglycaemic insulin clamp) and in silico modeling (GLUKINSLOOP.1) to compute the CCs of intravenous glucose tolerance in healthy insulin-sensitive (n = 9, NGR-IS), healthy insulin-resistant (n = 7, NGR-IR) and subdiabetic hyperglycemic (n = 8, PreT2DM) individuals and in patients with newly diagnosed type 2 diabetes (n = 7, T2DM). Altered insulin secretion and action were documented in NGR-IR and PreT2DM groups, but only 1st phase insulin secretion was significantly lower in T2DM than in PreT2DM (p < 0.05). The CCs changed little in the nondiabetic groups. However, several CCs were significantly altered in the patients (e.g. CCs of beta cell: -0.75 ± 0.10, -0.64 ± 0.15, -0.56 ± 0.09 and -0.19 ± 0.04 in NGR-IS, NGR-IR, PreT2DM and T2DM, respectively; p < 0.01 by MANOVA), and they could not be corrected by matching in silico nondiabetic and T2DM groups for 1st phase secretion. CONCLUSIONS: Type 2 diabetes is characterized not only by loss of function of the elements of the glucose-insulin system, but also by changes in systemic properties (CCs). As such, it could be considered a disease of the governance of the glucose-insulin system.
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Glucemia/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Homeostasis/fisiología , Insulina/fisiología , Adulto , Femenino , Técnica de Clampeo de la Glucosa , Intolerancia a la Glucosa/fisiopatología , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Células Secretoras de Insulina/fisiología , Masculino , Persona de Mediana Edad , Modelos Teóricos , FenotipoRESUMEN
We investigated cross-sectionally whether the type 2 diabetes (T2DM) risk alleles of rs1801282 (PPARG2) and rs4607103 (ADAMTS9) were associated with T2DM and/or insulin sensitivity (IS) and beta cell function (ßF) in Italians without and with newly diagnosed T2DM. In 676 nondiabetic subjects (336 NGR and 340 IGR) from the GENFIEV study and in 597 patients from the Verona Newly Diagnosed Type 2 Diabetes Study (VNDS), we (1) genotyped rs1801282 and rs4607103, (2) assessed ßF by C-peptide/glucose modeling after OGTT, and (3) assessed IS by HOMA-IR in both studies and by euglycemic insulin clamp in VNDS only. Logistic, linear, and two-stage least squares regression analyses were used to test (a) genetic associations with T2DM and with pathophysiological phenotypes, (b) causal relationships of the latter ones with T2DM by a Mendelian randomization design. Both SNPs were associated with T2DM. The rs4607103 risk allele was associated to impaired ßF (p < 0.01) in the GENFIEV study and in both cohorts combined. The rs1801282 genotype was associated with IS both in the GENFIEV study (p < 0.03) and in the VNDS (p < 0.03), whereas rs4607103 did so in the VNDS only (p = 0.01). In a Mendelian randomization design, both HOMA-IR (instrumental variables: rs1801282, rs4607103) and ßF (instrumental variable: rs4607103) were related to T2DM (p < 0.03-0.01 and p < 0.03, respectively). PPARG2 and ADAMTS9 variants are both associated with T2DM and with insulin resistance, whereas only ADAMTS9 may be related to ßF. Thus, at least in Italians, they may be considered bona fide "insulin resistance genes".
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Proteínas ADAM/genética , Diabetes Mellitus Tipo 2/genética , Resistencia a la Insulina/genética , PPAR gamma/genética , Proteína ADAMTS9 , Adulto , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Predisposición Genética a la Enfermedad/epidemiología , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Insulina/metabolismo , Secreción de Insulina , Italia/epidemiología , Masculino , Persona de Mediana Edad , Fenotipo , Mutación Puntual , Factores de RiesgoRESUMEN
AIMS/HYPOTHESIS: Diabetes frequently develops in patients with pancreatic disorders. We aimed to determine the lower threshold of beta cell area for diabetes manifestation as well as the impact of insulin sensitivity on glucose homoeostasis in patients with pancreatic diabetes. METHODS: Eighty-two patients undergoing pancreatic surgery underwent pre-operative oral glucose challenge. Fractional pancreatic beta cell area was determined, and indices of insulin sensitivity and beta cell function were calculated. RESULTS: HbA1c and glucose levels were similar in patients with high and intermediate beta cell area, but were significantly higher in those with the lowest beta cell area (p < 0.0001). Insulin secretion was reduced only in patients with the lowest beta cell area (p < 0.001). The relative beta cell deficits at the onset of diabetes and impaired glucose tolerance were 64% and 21%, respectively, based on 2 h glucose levels. Deteriorating insulin sensitivity was associated with a small increase in the incidence of diabetes. CONCLUSIONS/INTERPRETATION: In conclusion, pancreatic diabetes probably develops after a reduction in beta cell area of ~65%. Post-challenge glucose excursions are much more closely related to pancreatic beta cell area than to fasting glycaemia, thereby underlining the usefulness of the OGTT in patients with pancreatic disorders.
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Diabetes Mellitus/patología , Células Secretoras de Insulina/patología , Insulina/metabolismo , Páncreas/patología , Glucemia/metabolismo , Femenino , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/análisis , Humanos , Resistencia a la Insulina , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Persona de Mediana Edad , Tamaño de los ÓrganosRESUMEN
BACKGROUND AND AIM: We evaluated the relationship between insulin resistance (IR) and insulin secretion with the metabolic syndrome (MS) in 885 subjects (377 men/508 women, age 49±11 years, BMI 29±5.2kgm(-2)) at risk of diabetes enrolled in the genetics, pathophysiology and evolution of type 2 diabetes (GENFIEV) study. METHODS AND RESULTS: All subjects underwent a 75-g oral glucose tolerance test (OGTT) for the estimation of plasma levels of glucose and C-peptide, as well as fasting insulin and lipid profile. IR was arbitrarily defined as HOMA-IR value above the 75th centile of normal glucose tolerance (NGT) subjects. Overall MS prevalence (National Cholesterol Treatment Panel-Adult Treatment Panel (NCEP-ATPIII) criteria) was 33%, 19% in subjects with NGT, 42% in impaired fasting glucose (IFG), 34% in impaired glucose tolerance (IGT), 74% in IFG+IGT subjects, and 56% in newly diagnosed diabetic patients. Prevalence was slightly higher with IDF criteria. MS prevalence was >50% in subjects with 2h glucose >7.8mmoll(-1), independently of fasting plasma glucose. IR prevalence was higher in subjects with MS than in those without (63% vs. 23%; p<0.0001) and increased from 54% to 73% and 88% in the presence of three, four or five traits, respectively. IR occurred in 42% of subjects with non-diabetic alterations of glucose homeostasis, being the highest in those with IFG+IGT (IFG+IGT 53%, IFG 45%, IGT 38%; p<0.0001). Individuals with MS were more IR irrespective of glucose tolerance (p<0.0001) with no difference in insulinogenic index. Hypertriglyceridaemia (OR: 3.38; Confidence Interval, CI: 2.294.99), abdominal obesity (3.26; CI: 2.18-4.89), hyperglycaemia (3.02; CI: 1.80-5.07) and hypertension (1.69; CI: 1.12-2.55) were all associated with IR. CONCLUSIONS: These results show that in subjects with altered glucose tolerance (in particular IFG+IGT) MS prevalence is high and is generally associated to IR. Some combinations of traits of MS may significantly contribute to identify subjects with IR.
Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Síndrome Metabólico/epidemiología , Síndrome Metabólico/genética , Síndrome Metabólico/fisiopatología , Adulto , Glucemia/análisis , Péptido C/metabolismo , Femenino , Intolerancia a la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/fisiopatología , Hipertensión/fisiopatología , Resistencia a la Insulina , Italia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estado Prediabético , Prevalencia , Factores de RiesgoRESUMEN
CONTEXT: Intronic variants of TCF7L2 are confirmed genetic risk factors for type 2 diabetes and are associated to alterations in beta cell function in nondiabetic individuals. OBJECTIVE: The objective of the study was to test whether TCF7L2 variability may affect ß-cell function also in patients with type 2 diabetes. DESIGN: This was a cross-sectional association study. SETTING: The study was conducted at a university hospital referral center for diabetes. PATIENTS: Patients included 464 (315 males and 149 females) glutamic acid decarboxylase-negative patients [age: median 59 yr (interquartile range: 52-65); body mass index: 29.3 kg/m(2) (26.5-32.9); fasting plasma glucose: 7.0 mmol/liter (6.1-8.0)] with newly diagnosed type 2 diabetes. INTERVENTION(S): Interventions included frequently sampled oral glucose tolerance test and euglycemic insulin clamp. MAIN OUTCOME MEASURE(S): ß-Cell function (derivative control and proportional control); insulin sensitivity; genotypes of the following TCF7L2 single-nucleotide polymorphisms: rs7901695, rs7903146, rs11196205, and rs12255372. RESULTS: Both rs7901695 and rs7903146 diabetes risk alleles were associated with reduced proportional control of ß-cell function (P = 0.019 and P = 0.022, respectively). Two low-frequency haplotypes were associated with extreme (best and worst) phenotypes of ß-cell function (P < 0.01). No associations between TCF7L2 genotypes and insulin sensitivity were detected. CONCLUSIONS: TCF7L2 diabetes risk variants, either as single-nucleotide polymorphisms or as haplotypes, detrimentally influence ß-cell function and might play a role in determining the metabolic phenotype of patients with newly diagnosed type 2 diabetes.
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Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatología , Células Secretoras de Insulina/fisiología , Proteína 2 Similar al Factor de Transcripción 7/genética , Anciano , Alelos , Glucemia/metabolismo , Índice de Masa Corporal , Péptido C/metabolismo , Estudios de Cohortes , Estudios Transversales , Bases de Datos Factuales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Femenino , Variación Genética , Prueba de Tolerancia a la Glucosa , Haplotipos , Humanos , Hipoglucemiantes/uso terapéutico , Resistencia a la Insulina/genética , Resistencia a la Insulina/fisiología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Pruebas de Función Pancreática , Polimorfismo de Nucleótido Simple/genética , Factores de RiesgoRESUMEN
The present document contains recommendations for assessment, prevention and treatment of cardiovascular risk for HIV-infected patients. All recommendations were graded according to the strength and quality of the evidence and were voted on by 73 members of the Italian Cardiovascular Risk Guidelines Working Group which includes both experts in HIV/AIDS care and in cardiovascular and metabolic medicine. Since antiretroviral drug exposure represents only one risk factor, continued emphasis on an integrated management is given. This should include prevention and treatment of known cardiovascular risk factors (such as dyslipidaemia, diabetes, insulin resistance, healthy diet, physical activity, avoidance of smoking), but also rational switch of antiretroviral drugs. A rational switch strategy should consider both metabolic and anthropometric disturbances and effectiveness of antiretroviral regimens.
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Terapia Antirretroviral Altamente Activa/efectos adversos , Enfermedades Cardiovasculares/etiología , Infecciones por VIH/tratamiento farmacológico , Biomarcadores , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Complicaciones de la Diabetes , Interacciones Farmacológicas , Dislipidemias/complicaciones , Femenino , Infecciones por VIH/complicaciones , Humanos , Resistencia a la Insulina , Italia , Masculino , Factores de RiesgoRESUMEN
AIMS/HYPOTHESIS: The genetic architecture of model-derived parameters of beta cell function has never been assessed. Therefore, we estimated heritability (h(2)) for model-derived phenotypes of insulin secretion in twins. METHODS: Thirty-three monozygotic (MZ) and 23 dizygotic (DZ) twin pairs from the Finnish Twin Cohort Study underwent an OGTT (plasma glucose/C-peptide at 0, 30, 60, 90 and 120 min). A subset of the twin pairs (21 MZ/20 DZ) also underwent an IVGTT (frequent sampling of plasma glucose/insulin from 0 to 60 min) followed by a 160-min euglycaemic-hyperinsulinaemic clamp (45 mU.min(-1).m(-2)). Mathematical modelling was applied to the IVGTT and the OGTT to assess first-phase (readily releasable insulin [RRI]) and second-phase (sigma) secretion (IVGTT), and a global index of beta cell performance (OGTT beta index). Intraclass correlation coefficients and genetic and non-genetic components for trait variances were computed to assess the h(2) of model-derived parameters. RESULTS: The intraclass correlation coefficients in MZ twins were 0.78 for RRI, 0.67 for sigma and 0.57 for OGTT beta index. In DZ twins the correlation coefficients were 0.23, 0.32 and 0.42, respectively. Using the most parsimonious model for each trait, the h(2)--the proportion of variance accounted for by genetic factors--was 76% (95% CI: 53-88%) for RRI, 28% (34-80%) for sigma and 53% (26-72%) for OGTT beta index. CONCLUSIONS/INTERPRETATION: Our findings demonstrate that model-derived parameters of insulin secretion have a substantial genetic component and may be used in the search for genetic determinants of beta cell function in humans.
Asunto(s)
Prueba de Tolerancia a la Glucosa , Insulina/genética , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Bases de Datos Factuales , Femenino , Finlandia , Glucosa/farmacología , Técnica de Clampeo de la Glucosa , Humanos , Masculino , Modelos Estadísticos , Fenotipo , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
AIMS: To evaluate the cardiovascular risk associated with the presence of the Metabolic Syndrome in Type 2 diabetic subjects. METHODS: Subjects with the Metabolic Syndrome, defined by WHO criteria, were identified in a large sample of non-insulin-treated Type 2 diabetic patients examined within the Verona Diabetes Complications Study (n = 946). At baseline and after a mean of 4.5 years follow-up, cardiovascular disease (CVD) was assessed by medical history, physical examination, electrocardiogram (ECG) and echo-duplex of carotid and lower limb arteries. Death certificates and medical records of subjects who died during the follow-up were scrutinized in order to identify CVD deaths. In statistical analyses, CVD was considered as an aggregate end-point, including fatal and non-fatal coronary, cerebrovascular and peripheral vascular disease as well as ischaemic ECG abnormalities and vascular lesions at the echo-duplex. RESULTS: The proportion of subjects with the Metabolic Syndrome was very high (92.3%). At the baseline, 31.7% of subjects were coded positive for CVD, which was more prevalent in subjects with the Metabolic Syndrome (32.9 vs. 17.8%, P = 0.005). Among subjects free of CVD at the baseline (n = 559), CVD events during the follow-up were significantly increased in patients with the Metabolic Syndrome as compared with those without it (19.9% vs. 3.9%, P < 0.001). Multiple logistic regression analysis showed that, along with sex, age, smoking and HbA1c, the presence of the Metabolic Syndrome independently predicted prevalent (OR 2.01, P = 0.045) and incident CVD (OR 4.89, P = 0.031). CONCLUSIONS: In Type 2 diabetes, the presence of the Metabolic Syndrome is associated with an almost 5-fold increase in CVD risk.