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AIMS/HYPOTHESIS: We aimed to characterise the immunogenic background of insulin-dependent diabetes in a resource-poor rural African community. The study was initiated because reports of low autoantibody prevalence and phenotypic differences from European-origin cases with type 1 diabetes have raised doubts as to the role of autoimmunity in this and similar populations. METHODS: A study of consecutive, unselected cases of recently diagnosed, insulin-dependent diabetes (n = 236, ≤35 years) and control participants (n = 200) was carried out in the ethnic Amhara of rural North-West Ethiopia. We assessed their demographic and socioeconomic characteristics, and measured non-fasting C-peptide, diabetes-associated autoantibodies and HLA-DRB1 alleles. Leveraging genome-wide genotyping, we performed both a principal component analysis and, given the relatively modest sample size, a provisional genome-wide association study. Type 1 diabetes genetic risk scores were calculated to compare their genetic background with known European type 1 diabetes determinants. RESULTS: Patients presented with stunted growth and low BMI, and were insulin sensitive; only 15.3% had diabetes onset at ≤15 years. C-peptide levels were low but not absent. With clinical diabetes onset at ≤15, 16-25 and 26-35 years, 86.1%, 59.7% and 50.0% were autoantibody positive, respectively. Most had autoantibodies to GAD (GADA) as a single antibody; the prevalence of positivity for autoantibodies to IA-2 (IA-2A) and ZnT8 (ZnT8A) was low in all age groups. Principal component analysis showed that the Amhara genomes were distinct from modern European and other African genomes. HLA-DRB1*03:01 (p = 0.0014) and HLA-DRB1*04 (p = 0.0001) were positively associated with this form of diabetes, while HLA-DRB1*15 was protective (p < 0.0001). The mean type 1 diabetes genetic risk score (derived from European data) was higher in patients than control participants (p = 1.60 × 10-7). Interestingly, despite the modest sample size, autoantibody-positive patients revealed evidence of association with SNPs in the well-characterised MHC region, already known to explain half of type 1 diabetes heritability in Europeans. CONCLUSIONS/INTERPRETATION: The majority of patients with insulin-dependent diabetes in rural North-West Ethiopia have the immunogenetic characteristics of autoimmune type 1 diabetes. Phenotypic differences between type 1 diabetes in rural North-West Ethiopia and the industrialised world remain unexplained.
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Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Transportador 8 de Zinc/inmunología , Adolescente , Adulto , Edad de Inicio , Población Negra/genética , Péptido C/sangre , Niño , Diabetes Mellitus Tipo 1/genética , Etiopía , Femenino , Estudio de Asociación del Genoma Completo , Cadenas HLA-DRB1/genética , Humanos , Masculino , Análisis de Componente Principal , Adulto JovenRESUMEN
For optimal diabetes management HbA1c, lipid and renal function measurements are key. Suitable point-of-care systems can provide such data in remote areas, diabetes camps, disaster relief, small community hospitals and in community screening days in disadvantaged regions. Some systems are currently used in Australian rural, remote and indigenous health services.
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Servicios de Salud del Indígena , Servicios de Salud Rural , Australia/epidemiología , Hemoglobina Glucada/análisis , Humanos , Lípidos , Nativos de Hawái y Otras Islas del Pacífico , Pruebas en el Punto de Atención , Poblaciones VulnerablesRESUMEN
PURPOSE OF REVIEW: Very little is known about the occurrence of type 1 diabetes (T1DM) in resource-poor countries and particularly in their rural hinterlands. RECENT FINDINGS: Studies of the epidemiology of T1DM in Ethiopia and similar countries in sub-Saharan Africa show that the pattern of presenting disease differs substantially from that in the West. Typically, the peak age of onset of the disease is more than a decade later with a male excess and a low prevalence of indicators of islet-cell autoimmunity. It is also associated with markers of undernutrition. These findings raise the question as to whether the principal form of T1DM seen in these resource-poor communities has a different pathogenesis. Whether the disease is a direct result of malnutrition or whether malnutrition may modify the expression of islet-cell autoimmunity is unclear. However, the poor prognosis in these settings underlines the urgent need for detailed clinical and epidemiological studies.
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Diabetes Mellitus Tipo 1/complicaciones , Recursos en Salud , Desnutrición/complicaciones , Autoinmunidad , Diabetes Mellitus Tipo 1/inmunología , Etiopía , Humanos , Islotes Pancreáticos/inmunologíaAsunto(s)
Diabetes Gestacional , Hiperglucemia , Glucemia , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Embarazo , Resultado del EmbarazoRESUMEN
Background: While there is increasing evidence for an altered clinical phenotype of Type 1 diabetes in several low-and middle-income countries, little is known about urban-rural differences and how the greater poverty of rural environments may alter the pattern of disease. Objective: Investigation of urban-rural differences in demographic and anthropometric characteristics of type 1 diabetes in a resource-poor setting. Research design and methods: Analysis of a unique case register, comprising all patients (rural and urban) presenting with Type 1 diabetes over a 20 yr. period in a poor, geographically defined area in northwest Ethiopia. The records included age, sex, place of residence, together with height and weight at the clinical onset. Results: A total of 1682 new cases of Type 1 diabetes were registered with a mean age of onset of 31.2 (SD 13.4) yr. The patients were thin with 1/3 presenting with a body mass index (BMI) <17kg/m2. There was a striking male predominance of cases when clinical onset was between 20 and 35 yr., this was more marked in the very poor rural dwellers compared to the urban population. While most patients with Type 1 diabetes presented with low BMIs and reduced height, stunting preferentially affected rural men. Conclusions: These data have led to the hypothesis that complex interactions among poor socioeconomic conditions in early life affect both pancreatic function and the development of autoimmunity and provide a possible explanation of the unusual phenotype of Type 1 diabetes in this very poor community.
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Obese AT (adipose tissue) exhibits increased macrophage number. Pro-inflammatory CD16+ peripheral monocyte numbers are also reported to increase with obesity. The present study was undertaken to simultaneously investigate obesity-associated changes in CD16+ monocytes and ATMs (AT macrophages). In addition, a pilot randomized placebo controlled trial using the PPAR (peroxisome-proliferator-activated receptor) agonists, pioglitazone and fenofibrate was performed to determine their effects on CD14+/CD16+ monocytes, ATM and cardiometabolic and adipose dysfunction indices. Obese glucose-tolerant men (n=28) were randomized to placebo, pioglitazone (30 mg/day) and fenofibrate (160 mg/day) for 12 weeks. A blood sample was taken to assess levels of serum inflammatory markers and circulating CD14+/CD16+ monocyte levels via flow cytometry. A subcutaneous AT biopsy was performed to determine adipocyte cell surface and ATM number, the latter was determined via assessment of CD68 expression by IHC (immunohistochemistry) and real-time PCR. Subcutaneous AT mRNA expression of CEBPß (CCAAT enhancer-binding protein ß), SREBP1c (sterol-regulatory-element-binding protein 1c), PPARγ2, IRS-1 (insulin receptor substrate-1), GLUT4 (glucose transporter type 4) and TNFα (tumour necrosis factor α) were also assessed. Comparisons were made between obese and lean controls (n=16) at baseline, and pre- and post-PPAR agonist treatment. Obese individuals had significantly increased adipocyte cell surface, percentage CD14+/CD16+ monocyte numbers and ATM number (all P=0.0001). Additionally, serum TNF-α levels were significantly elevated (P=0.017) and adiponectin levels reduced (total: P=0.0001; high: P=0.022) with obesity. ATM number and percentage of CD14+/CD16+ monocytes correlated significantly (P=0.05). Pioglitazone improved adiponectin levels significantly (P=0.0001), and resulted in the further significant enlargement of adipocytes (P=0.05), without effect on the percentage CD14+/CD16+ or ATM number. Pioglitazone treatment also significantly increased subcutaneous AT expression of CEBPß mRNA. The finding that improvements in obesity-associated insulin resistance following pioglitazone were associated with increased adipocyte cell surface and systemic adiponectin levels, supports the centrality of AT to the cardiometabolic derangement underlying the development of T2D (Type 2 diabetes) and CVD (cardiovascular disease).
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Tejido Adiposo/fisiopatología , Proteína beta Potenciadora de Unión a CCAAT/genética , Obesidad/tratamiento farmacológico , Obesidad/fisiopatología , Recuperación de la Función , Tiazolidinedionas/uso terapéutico , Regulación hacia Arriba/genética , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adiponectina/metabolismo , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Adulto , Anciano , Antropometría , Biomarcadores/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Enfermedades Cardiovasculares/patología , Recuento de Células , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Citocinas/sangre , Fenofibrato/farmacología , Fenofibrato/uso terapéutico , Prueba de Tolerancia a la Glucosa , Humanos , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Obesidad/sangre , Pioglitazona , Recuperación de la Función/efectos de los fármacos , Factores de Riesgo , Tiazolidinedionas/farmacología , Regulación hacia Arriba/efectos de los fármacosRESUMEN
BACKGROUND: It is controversial whether maternal hyperglycemia less severe than that in diabetes mellitus is associated with increased risks of adverse pregnancy outcomes. METHODS: A total of 25,505 pregnant women at 15 centers in nine countries underwent 75-g oral glucose-tolerance testing at 24 to 32 weeks of gestation. Data remained blinded if the fasting plasma glucose level was 105 mg per deciliter (5.8 mmol per liter) or less and the 2-hour plasma glucose level was 200 mg per deciliter (11.1 mmol per liter) or less. Primary outcomes were birth weight above the 90th percentile for gestational age, primary cesarean delivery, clinically diagnosed neonatal hypoglycemia, and cord-blood serum C-peptide level above the 90th percentile. Secondary outcomes were delivery before 37 weeks of gestation, shoulder dystocia or birth injury, need for intensive neonatal care, hyperbilirubinemia, and preeclampsia. RESULTS: For the 23,316 participants with blinded data, we calculated adjusted odds ratios for adverse pregnancy outcomes associated with an increase in the fasting plasma glucose level of 1 SD (6.9 mg per deciliter [0.4 mmol per liter]), an increase in the 1-hour plasma glucose level of 1 SD (30.9 mg per deciliter [1.7 mmol per liter]), and an increase in the 2-hour plasma glucose level of 1 SD (23.5 mg per deciliter [1.3 mmol per liter]). For birth weight above the 90th percentile, the odds ratios were 1.38 (95% confidence interval [CI], 1.32 to 1.44), 1.46 (1.39 to 1.53), and 1.38 (1.32 to 1.44), respectively; for cord-blood serum C-peptide level above the 90th percentile, 1.55 (95% CI, 1.47 to 1.64), 1.46 (1.38 to 1.54), and 1.37 (1.30 to 1.44); for primary cesarean delivery, 1.11 (95% CI, 1.06 to 1.15), 1.10 (1.06 to 1.15), and 1.08 (1.03 to 1.12); and for neonatal hypoglycemia, 1.08 (95% CI, 0.98 to 1.19), 1.13 (1.03 to 1.26), and 1.10 (1.00 to 1.12). There were no obvious thresholds at which risks increased. Significant associations were also observed for secondary outcomes, although these tended to be weaker. CONCLUSIONS: Our results indicate strong, continuous associations of maternal glucose levels below those diagnostic of diabetes with increased birth weight and increased cord-blood serum C-peptide levels.
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Hiperglucemia/complicaciones , Complicaciones del Embarazo , Resultado del Embarazo , Adulto , Glucemia/análisis , Péptido C/sangre , Cesárea/estadística & datos numéricos , Femenino , Sangre Fetal/química , Macrosomía Fetal/epidemiología , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/sangre , Hipoglucemia/epidemiología , Hipoglucemia/etiología , Recién Nacido , Oportunidad Relativa , Embarazo , Complicaciones del Embarazo/sangreRESUMEN
OBJECTIVE: To investigate the level of diabetic retinopathy in type 2 diabetes (T2DM) patients attending the University of Gondar Hospital (UGH) Diabetic Clinic, Northwest Ethiopia. METHODS: An audit was carried out involving a total of 739 T2DM patients attending at the diabetic clinic of UGH. They represented approximately 90% and 50% of all T2DM patients under regular review at the urban and rural diabetic clinics of UGH, respectively. All were supervised by the same clinical team for a long period. Eye examinations were performed for visual acuity, cataract, and retinal changes (retinal photography and slit-lamp biomicroscopy). Body mass index (BMI) and HbA1c levels were measured. The presence or absence of hypertension was recorded. RESULTS: Men constituted 41.5% of the group, the mean age at diagnosis of T2DM was 50.4 years, and 50.2% were hypertensive. The BMI was 25.0 ± 4.1 kg/m2, and HbA1c was 7.75 ± 1.63% (61.2 ± 17.8 mmol/mol) (mean ± SD, for BMI and HbA1c)). Severe visual impairment/blindness was reported in 10.6%, 15.2% had cataract, 16.0% had retinopathy, and 11.1% had maculopathy. The prevalence of retinopathy increased with time from diagnosis of T2DM (chi-square for trend, p < 0.001) and with increasing HbA1c level (chi-square for trend, p=0.03). CONCLUSION: These results compare well with the most recent results in well-equipped, wealthier regions of the world and show the importance of stable healthcare infrastructure for chronic-disease management.
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Hyperglycemia increases expression of platelet-derived growth factor (PDGF)-beta receptor and potentiates chemotaxis to PDGF-BB in human aortic vascular smooth muscle cells (VSMCs) via PI3K and ERK/MAPK signaling pathways. The purpose of this study was to determine whether increased activation of protein kinase C (PKC) isoforms had a modulatory effect on the PI3K and ERK/MAPK pathways, control of cell adhesiveness, and movement. All known PKC isoforms were assessed but only PKCalpha and PKCbetaII levels were increased in 25 mmol/L glucose. However, only PKCbetaII inhibition affected (decreased) PI3K pathway and MAPK pathway activities and inhibited PDGF-beta receptor upregulation in raised glucose, and specific MAPK inhibition was required to completely block the effect of glucose. In raised glucose conditions, activity of the ERK/MAPK pathway, PI3K pathway, and PKCbetaII were all sensitive to aldose reductase inhibition. Chemotaxis to PDGF-BB (360 pmol/L), absent in 5 mmol/L glucose, was present in raised glucose and could be blocked by PKCbetaII inhibition. Formation of lamellipodia was dependent on PI3K activation and filopodia on MAPK activation; both lamellipodia and filopodia were eliminated when PKCbetaII was inhibited. FAK phosphorylation and cell adhesion were reduced by PI3K inhibition, and although MAPK inhibition prevented chemotaxis, it did not affect FAK phosphorylation or cell adhesiveness. In conclusion, chemotaxis to PDGF-BB in 25 mmol/L glucose is PKCbetaII-dependent and requires activation of both the PI3K and MAPK pathways. Changes in cell adhesion and migration speed are mediated mainly through the PI3K pathway.
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Quimiotaxis/fisiología , Isoenzimas/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/enzimología , Fosfatidilinositol 3-Quinasas/fisiología , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteína Quinasa C/fisiología , Transducción de Señal/fisiología , Aorta , Becaplermina , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Quimiotaxis/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Inducción Enzimática/efectos de los fármacos , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Adhesiones Focales/efectos de los fármacos , Adhesiones Focales/fisiología , Glucosa/farmacología , Humanos , Hiperglucemia/enzimología , Hiperglucemia/fisiopatología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/fisiología , Fosforilación/efectos de los fármacos , Proteína Quinasa C beta , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/farmacología , Proteínas Tirosina Quinasas/fisiología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/farmacología , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-sis , Seudópodos/efectos de los fármacos , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Sorbitol/metabolismoRESUMEN
Blood levels of inflammatory markers associated with endothelial dysfunction and atherosclerosis are increased in diabetic patients; the highest levels occur in poorly controlled diabetes. We investigated the activation state of peripheral blood monocytes in diabetes with respect to scavenger receptor (CD36) expression and monocyte chemoattractant protein-1, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and peroxisome proliferator-activated receptors mRNA expression. CD14(+) monocytes were isolated from peripheral blood of type 1 and type 2 diabetic patients with good (HbA(1c) <7.0%) or poor (>9.4%) glycemic control and a group of nondiabetic subjects. Monocytes from diabetic subjects displayed increased CD36 cell surface expression (P < 0.0005) and increased uptake of oxidized LDL (P < 0.05). Monocyte chemoattractant protein-1 gene expression was increased in monocytes from both groups of diabetic subjects (P < 0.05). Both CD68 and peroxisome proliferator-activated receptor-gamma gene expression were increased in the poorly controlled diabetic group (P < 0.05 for each), whose monocytes also displayed increased attachment to endothelial monolayers (P < 0.0005 vs. nondiabetic control subjects). In poorly controlled diabetes, CD14(+) monocytes are functionally activated and show some of the differentiation markers associated with macrophages. These monocytes also demonstrate an increased ability for attachment to normal endothelial cells, one of the early stages in atherogenesis.
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Antígenos CD36/fisiología , Diabetes Mellitus/fisiopatología , Receptores de Lipopolisacáridos/fisiología , Monocitos/fisiología , Adulto , Anciano , Antígenos CD/fisiología , Antígenos de Diferenciación Mielomonocítica/fisiología , Biomarcadores , Glucemia/fisiología , Adhesión Celular/fisiología , Quimiocina CCL2/metabolismo , Femenino , Expresión Génica/fisiología , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Receptores Activados del Proliferador del Peroxisoma/metabolismo , ARN Mensajero/metabolismo , Receptores de LDL/fisiología , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Atheroma formation involves the movement of vascular smooth muscle cells (VSMC) into the subendothelial space. The aim of this study was to determine the involvement of PI3K and MAPK pathways and the importance of cross-talk between these pathways, in glucose-potentiated VSMC chemotaxis to serum factors. VSMC chemotaxis occurred in a serum gradient in 25 mmol/L glucose (but not in 5 mmol/L glucose) in association with increased phosphorylation (activation) of Akt and ERK1/2 in PI3K and MAPK pathways, respectively. Inhibitors of these pathways blocked chemotaxis, as did an mTOR inhibitor. VSMC expressed all class IA PI3K isoforms, but microinjection experiments demonstrated that only the p110beta isoform was involved in chemotaxis. ERK1/2 phosphorylation was reduced not only by MAPK pathway inhibitors but also by PI3K and mTOR inhibitors; when PI3K was inhibited, ERK phosphorylation could be induced by microinjected activated Akt, indicating important cross-talk between the PI3K and ERK1/2 pathways. Glucose-potentiated phosphorylation of molecules in the p38 and JNK MAPK pathways inhibited these pathways but did not affect chemotaxis. The statin, mevinolin, blocked chemotaxis through its effects on the MAPK pathway. Mevinolin-inhibited chemotaxis was restored by farnesylpyrophosphate but not by geranylgeranylpyrophosphate; in the absence of mevinolin, inhibition of farnesyltransferase reduced ERK phosphorylation and blocked chemotaxis, indicating a role for the Ras family of GTPases (MAPK pathway) under these conditions. In conclusion, glucose sensitizes VSMC to serum, inducing chemotaxis via pathways involving p110beta-PI3K, Akt, mTOR, and ERK1/2 MAPK. Cross-talk between the PI3K and MAPK pathways is necessary for VSMC chemotaxis under these conditions.
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Quimiotaxis/efectos de los fármacos , Glucosa/farmacología , Sistema de Señalización de MAP Quinasas , Músculo Liso Vascular/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/fisiología , Transferasas Alquil y Aril/antagonistas & inhibidores , Androstadienos/farmacología , Antracenos/farmacología , Anticuerpos Monoclonales/farmacología , Células Cultivadas/citología , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Quimiotaxis/fisiología , Cromonas/farmacología , Fosfatidilinositol 3-Quinasa Clase I , Farnesiltransferasa , Flavonoides/farmacología , Humanos , Imidazoles/farmacología , Isoenzimas/antagonistas & inhibidores , Isoenzimas/fisiología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas JNK Activadas por Mitógenos/fisiología , Lovastatina/farmacología , MAP Quinasa Quinasa 4 , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/fisiología , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/fisiología , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Morfolinas/farmacología , Músculo Liso Vascular/fisiología , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/fisiología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfatos de Poliisoprenilo/farmacología , Proteínas Quinasas/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-akt , Piridinas/farmacología , Sesquiterpenos , Sirolimus/farmacología , Serina-Treonina Quinasas TOR , Wortmanina , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Proteínas ras/fisiologíaRESUMEN
The aim of this study was to investigate the effects of elevated D-glucose concentrations on vascular smooth muscle cell (VSMC) expression of the platelet-derived growth factor (PDGF)beta receptor and VSMC migratory behavior. Immunoprecipitation, immunofluorescent staining, and RT-PCR of human VSMCs showed that elevated D-glucose induced an increase in the PDGFbeta receptor that was inhibited by phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathway inhibitors. Exposure to 25 mmol/l D-glucose (HG) induced increased phosphorylation of protein kinase B (PKB) and extracellular-regulated kinase (ERK). All HG chemotaxis assays (with either 10 days' preincubation in HG or no preincubation) in a FCS or PDGF-BB gradient showed positive chemotaxis, whereas those in 5 mmol/l D-glucose did not. Assays were also run with concentrations ranging from 5 to 25 mmol/l D-glucose. Chemotaxis was induced at concentrations > or =9 mmol/l D-glucose. An anti-PDGFbeta receptor antibody inhibited glucose-potentiated VSMC chemotaxis, as did the inhibitors for the PI3K and MAPK pathways. This study has shown that small increases in D-glucose concentration, for a short period, increase VSMC expression of the PDGFbeta receptor and VSMC sensitivity to chemotactic factors in serum, leading to altered migratory behavior in vitro. It is probable that similar processes occur in vivo with glucose-enhanced chemotaxis of VSMCs, operating through PDGFbeta receptor-operated pathways, contributing to the accelerated formation of atheroma in diabetes.
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Quimiotaxis/fisiología , Regulación de la Expresión Génica/fisiología , Glucosa/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Músculo Liso Vascular/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Androstadienos/farmacología , Animales , Aorta/fisiología , Aorta Torácica , Cromonas/farmacología , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Morfolinas/farmacología , Músculo Liso Vascular/efectos de los fármacos , Fosforilación , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Porcinos , WortmaninaRESUMEN
AIM: To audit levels of diabetes-related eye disease in Type 1 diabetes mellitus (T1DM) patients in northwest Ethiopia. In particular to establish whether, despite identical clinical goals, major differences between the physically demanding life-style of rural subsistence farmers and the sedentary life-style of urban dwellers would influence the prevalence of diabetes-related eye complications. METHODS: A robust infrastructure for chronic disease management that comprehensively includes all rural dwellers was a pre-requisite for the investigation. A total of 544 T1DM were examined, representing 80% of all T1DM patients under regular review at both the urban and rural clinics and representative of patient age and gender (62.1% male, 37.9% female) of T1DM patients from this region; all were supervised by the same clinical team. Eye examinations were performed for visual acuity, cataract and retinal changes (retinal photography). HbA1c levels and the presence or absence of hypertension were recorded. RESULTS/CONCLUSIONS: Urban and rural groups had similar prevalences of severe visual impairment/blindness (7.0% urban, 5.2% rural) and cataract (7.3% urban, 7.1% rural). By contrast, urban dwellers had a significantly higher prevalence of retinopathy compared to rural patients, 16.1% and 5.0%, respectively (OR 2.9, p<0.02, after adjustment for duration, age, gender and hypertension). There was a 3-fold greater prevalence of hypertension in urban patients, whereas HbA1c levels were similar in the two groups. Since diabetic retinopathy is closely associated with microvascular disease and endothelial dysfunction, the possible influences of hypertension to increase and of sustained physical activity to reduce endothelial dysfunction are discussed.
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Diabetes Mellitus Tipo 1/epidemiología , Retinopatía Diabética/epidemiología , Población Rural/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Adulto , Ceguera/epidemiología , Catarata/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Retinopatía Diabética/etiología , Etiopía/epidemiología , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Estilo de Vida , Masculino , Persona de Mediana Edad , Prevalencia , Agudeza Visual , Adulto JovenRESUMEN
Diabetes is associated with oxidative stress and increased concentrations of inflammatory cytokines. The aim of the study was to assess the effects of inflammatory cytokines and oxidative stress associated with increased glucose concentrations on inducible nitric oxide synthase (iNOS) promoter activity in intestinal epithelial cells. High-glucose (25 mmol/l) conditions reduced glutathione (GSH) concentrations in the human intestinal epithelial cell line, DLD-1. Addition of the antioxidant, alpha-lipoic acid, resulted in the restoration of GSH concentrations to normal. Upregulation of basal iNOS promoter activity was observed when cells were incubated in high glucose alone. This effect was significantly reduced by the addition of the antioxidant, alpha-lipoic acid, and completely blocked with inhibition of nuclear factor kappa B (NFkappaB) activity. Stimulation of cytokines (interleukin-1 beta, tumour necrosis factor-alpha, interferon-gamma) induced iNOS promoter activity in all conditions and this was accompanied by an increase in nitric oxide (NO) production. Inhibition of NFkappaB activity decreased, but did not completely inhibit, cytokine-induced iNOS promoter activity and subsequent production of NO. In conclusion, iNOS promoter activity induced by high concentrations of glucose is mediated in part through intracellular GSH and NFkappaB.
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Células Epiteliales/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Glutatión/metabolismo , Intestinos/citología , Óxido Nítrico Sintasa/genética , Línea Celular Tumoral , Células Epiteliales/metabolismo , Humanos , Nitratos/metabolismo , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Nitritos/metabolismo , Regiones Promotoras Genéticas/genética , Regulación hacia Arriba/efectos de los fármacosRESUMEN
The effects of polyunsaturated n-6 linoleic acid on monocyte-endothelial interactions were investigated with particular emphasis on the expression of platelet/endothelial cell adhesion molecule (PECAM)-1 and the role of protein kinase C (PKC) and cyclooxygenase-2 (COX-2). As a diet rich in polyunsaturated fatty acids may favour atherosclerosis in hyperglycaemia, this study was performed in both normal and high-glucose media using human aortic endothelial cells (HAEC). The HAEC were preincubated with normal (5 mM) or high (25 mM) D-glucose for 3 days before addition of fatty acids (0.2 mM) for 3 days. Linoleic acid enhanced PECAM-1 expression independently of tumor necrosis factor (TNF)-α and significantly increased TNF-α-induced monocyte adhesion to HAEC in comparison to the monounsaturated n-9 oleic acid. Chronic glucose treatment (25 mM, 6 days) did not modify the TNF-α-induced or fatty acid-induced changes in monocyte binding. The increase in monocyte binding was accompanied by a significant increase in E-selectin and vascular cell adhesion molecule (VCAM)-1 expression and could be abrogated by an interleukin (IL)-8 neutralising antibody and by the PKC and COX inhibitors. Inhibition of PKC-δ reduced VCAM-1 expression regardless of experimental condition and was accompanied by a significant decrease in monocyte binding. Conditioned medium from linoleic acid-treated HAEC grown in normal glucose conditions significantly increased THP-1 chemotaxis. These results suggest that linoleic acid-induced changes in monocyte chemotaxis and subsequent binding are not solely mediated by changes in adhesion molecule expression but may be due to secreted factors such as IL-8, monocyte chemoattractant protein-1 or prostaglandins (PGs) such as PGE(2), as IL-8 neutralisation and COX-2 inhibition reduced monocyte binding without changes in adhesion molecule expression.
Asunto(s)
Moléculas de Adhesión Celular/efectos de los fármacos , Quimiotaxis de Leucocito/efectos de los fármacos , Ciclooxigenasa 2/genética , Células Endoteliales/efectos de los fármacos , Ácido Linoleico/farmacología , Monocitos/efectos de los fármacos , Proteína Quinasa C/metabolismo , Aorta/citología , Aorta/efectos de los fármacos , Aorta/metabolismo , Glucemia/análisis , Células Cultivadas , Quimiocina CCL2/metabolismo , Ciclooxigenasa 2/metabolismo , Selectina E/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Humanos , Interleucina-8/metabolismo , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/genética , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
OBJECTIVE: To report frequencies of gestational diabetes mellitus (GDM) among the 15 centers that participated in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study using the new International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria. RESEARCH DESIGN AND METHODS: All participants underwent a 75-g oral glucose tolerance test between 24 and 32 weeks' gestation. GDM was retrospectively classified using the IADPSG criteria (one or more fasting, 1-h, or 2-h plasma glucose concentrations equal to or greater than threshold values of 5.1, 10.0, or 8.5 mmol/L, respectively). RESULTS: Overall frequency of GDM was 17.8% (range 9.3-25.5%). There was substantial center-to-center variation in which glucose measures met diagnostic thresholds. CONCLUSIONS: Although the new diagnostic criteria for GDM apply globally, center-to-center differences occur in GDM frequency and relative diagnostic importance of fasting, 1-h, and 2-h glucose levels. This may impact strategies used for the diagnosis of GDM.
Asunto(s)
Diabetes Gestacional/epidemiología , Adulto , Glucemia/análisis , Diabetes Gestacional/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/sangre , Hiperglucemia/diagnóstico , Embarazo , Adulto JovenRESUMEN
OBJECTIVE: To determine associations of gestational diabetes mellitus (GDM) and obesity with adverse pregnancy outcomes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study. RESEARCH DESIGN AND METHODS: Participants underwent a 75-g oral glucose tolerance test (OGTT) between 24 and 32 weeks. GDM was diagnosed post hoc using International Association of Diabetes and Pregnancy Study Groups criteria. Neonatal anthropometrics and cord serum C-peptide were measured. Adverse pregnancy outcomes included birth weight, newborn percent body fat, and cord C-peptide >90th percentiles, primary cesarean delivery, preeclampsia, and shoulder dystocia/birth injury. BMI was determined at the OGTT. Multiple logistic regression was used to examine associations of GDM and obesity with outcomes. RESULTS: Mean maternal BMI was 27.7, 13.7% were obese (BMI ≥33.0 kg/m(2)), and GDM was diagnosed in 16.1%. Relative to non-GDM and nonobese women, odds ratio for birth weight >90th percentile for GDM alone was 2.19 (1.93-2.47), for obesity alone 1.73 (1.50-2.00), and for both GDM and obesity 3.62 (3.04-4.32). Results for primary cesarean delivery and preeclampsia and for cord C-peptide and newborn percent body fat >90th percentiles were similar. Odds for birth weight >90th percentile were progressively greater with both higher OGTT glucose and higher maternal BMI. There was a 339-g difference in birth weight for babies of obese GDM women, compared with babies of normal/underweight women (64.2% of all women) with normal glucose based on a composite OGTT measure of fasting plasma glucose and 1- and 2-h plasma glucose values (61.8% of all women). CONCLUSIONS: Both maternal GDM and obesity are independently associated with adverse pregnancy outcomes. Their combination has a greater impact than either one alone.
Asunto(s)
Diabetes Gestacional/epidemiología , Hiperglucemia/epidemiología , Obesidad/epidemiología , Complicaciones del Trabajo de Parto/epidemiología , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Adulto , Peso al Nacer/fisiología , Glucemia/análisis , Glucemia/metabolismo , Índice de Masa Corporal , Diabetes Gestacional/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/sangre , Hiperglucemia/complicaciones , Recién Nacido , Masculino , Obesidad/complicaciones , Complicaciones del Trabajo de Parto/sangre , Complicaciones del Trabajo de Parto/etiología , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/etiología , Adulto JovenRESUMEN
OBJECTIVE: To compare associations of maternal glucose and A1C with adverse outcomes in the multinational Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study and determine, based on those comparisons, if A1C measurement can provide an alternative to an oral glucose tolerance test (OGTT) in pregnant women. RESEARCH DESIGN AND METHODS: Eligible pregnant women underwent a 75-g OGTT at 24-32 weeks' gestation. A sample for A1C was also collected. Neonatal anthropometrics and cord serum C-peptide were measured. Associations with outcomes were assessed using multiple logistic regression with adjustment for potential confounders. RESULTS: Among 23,316 HAPO Study participants with glucose levels blinded to caregivers, 21,064 had a nonvariant A1C result. The mean ± SD A1C was 4.79 ± 0.40%. Associations were significantly stronger with glucose measures than with A1C for birth weight, sum of skinfolds, and percent body fat >90th percentile and for fasting and 1-h glucose for cord C-peptide (all P < 0.01). For example, in fully adjusted models, odds ratios (ORs) for birth weight >90th percentile for each measure higher by 1 SD were 1.39, 1.45, and 1.38, respectively, for fasting, 1-, and 2-h plasma glucose and 1.15 for A1C. ORs for cord C-peptide >90th percentile were 1.56, 1.45, and 1.35 for glucose, respectively, and 1.32 for A1C. ORs were similar for glucose and A1C for primary cesarean section, preeclampsia, and preterm delivery. CONCLUSIONS: On the basis of associations with adverse outcomes, these findings suggest that A1C measurement is not a useful alternative to an OGTT in pregnant women.
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Hemoglobina Glucada/metabolismo , Hiperglucemia/fisiopatología , Adulto , Glucemia/metabolismo , Diabetes Gestacional/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/complicaciones , Embarazo , Resultado del EmbarazoRESUMEN
OBJECTIVE: The goal was to describe the temporal pattern of neonatal plasma glucose levels and associations with maternal glucose levels, cord serum C-peptide levels, and neonatal size and adiposity. METHODS: A total of 17,094 mothers and infants were included in the Hyperglycemia and Adverse Pregnancy Outcome Study (15 centers in 9 countries). Mothers underwent a 75-g, 2-hour, oral glucose tolerance test (OGTT) at 24 to 32 weeks of gestation. Cord blood and neonatal blood samples were collected. Biochemical neonatal hypoglycemia was defined as glucose levels of <10th percentile (2.2 mmol/L). Clinically identified hypoglycemia was ascertained through medical record review and associations were assessed. RESULTS: Plasma glucose concentrations were stable during the first 5 hours after birth. Maternal glucose levels were weakly positively associated with biochemical neonatal hypoglycemia (odds ratios: 1.07-1.14 for 1-SD higher OGTT glucose levels). Frequency of neonatal hypoglycemia was higher with higher cord C-peptide levels (odds ratio: 11.6 for highest versus lowest C-peptide category). Larger and/or fatter infants were more likely to have hypoglycemia (P < .001), and infants with hypoglycemia tended to have a higher frequency of cord C-peptide levels of >90th percentile. CONCLUSIONS: Mean neonatal plasma glucose concentrations varied little in the first 5 hours after birth, which suggests normal postnatal adjustment. Biochemical and clinical hypoglycemia were weakly related to maternal OGTT glucose measurements but were strongly associated with elevated cord serum C-peptide levels. Larger and/or fatter infants were more likely to develop hypoglycemia and hyperinsulinemia. These relationships suggest physiologic relationships between maternal glycemia and fetal insulin production.
Asunto(s)
Glucemia/metabolismo , Péptido C/sangre , Hiperglucemia/complicaciones , Enfermedades del Recién Nacido/etiología , Insulina/sangre , Complicaciones del Embarazo/sangre , Adulto , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/sangre , Hipoglucemia/sangre , Hipoglucemia/etiología , Recién Nacido , Enfermedades del Recién Nacido/sangre , Embarazo , Resultado del Embarazo , Factores de RiesgoRESUMEN
BACKGROUND: Measurement of glucose in multiple Field Laboratories requires rigorous standardization when patients and caregivers are masked, unless predefined thresholds are met. Local misclassification of participants at the thresholds can introduce recruitment bias and adversely affect the integrity of study findings. PURPOSE: To describe the challenges and the approach to meeting them in measuring glucose, HbA1c, and C-peptide in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study. HAPO is an observational epidemiologic study of 25 000 pregnant women from 15 centres in 10 countries, designed to clarify unanswered questions on associations of maternal glycemia, less severe than overt diabetes mellitus, with risks of adverse pregnancy outcome. METHODS: Glucose tolerance (75 g two-hour OGTT) is assessed locally at 24-32 weeks' gestation, with results masked if fasting and two-hour plasma glucose are =5.8 mmol/L and =11.1 mmol/L, respectively. For analysis of outcomes HAPO utilizes measurements of glucose, C-peptide, and HbA1c on frozen samples in a Central Laboratory; measurement of HbA1c on stored, frozen blood also creates special challenges. A common external quality assessment scheme was used to standardize glucose measurements between Field Centre and Central Laboratories before and during data collection. RESULTS: Agreement between Field Centres and the Central Laboratory in rates above the masking thresholds has been excellent (Kappa = 0.79, P < 0.001), with rates of 1.8 and 1.7% respectively. Percent technical error for Central Laboratory OGTT measurements of glucose, C-peptide, and HbA1c, were 2.0, 4.2, and 2.0, respectively. LIMITATIONS: It is not possible to assess if comparable results could have been obtained with a less rigorous approach to standardization. CONCLUSIONS: HAPO has been successful in ensuring comparability of glucose measurement between its Central Laboratory and Field Centre laboratories and in measuring its key metabolites with accuracy and precision. Recruitment bias based on glucose measurement has been avoided.