Leptin is thought to be a lipostatic signal that contributes to body weight regulation. Zinc might play an important role in appetite regulation and its administration stimulates leptin production. However, there are few reports in the literature on its role on leptin levels in the obese population. The present work assesses the effect of zinc supplementation on serum leptin levels in insulin resistance (IR). A prospective double-blind, randomized, clinical, placebo-controlled study was conducted. Fifty-six normal glucose-tolerant obese women (age: 25-45 yr, body mass index [BMI] = 36.2 +/- 2.3 kg/m2) were randomized for treatment with 30 mg zinc daily for 4 wk. Baseline values of both groups were similar for age, BMI, caloric intake, insulin concentration, insulin resistance, and zinc concentration in diet, plasma, urine, and erythrocytes. Insulin and leptin were measured by radioimmunoassay and IR was estimated by the homeostasis model assessment (HOMA). The determinations of zinc in plasma, erythrocytes, and 24- h urine were performed by using atomic absorption spectrophotometry. After 4 wk, BMI, fasting glucose, and zinc concentration in plasma and erythrocyte did not change in either group, although zinc concentration in the urine increased from 385.9 +/- 259.3 to 470.2 +/- 241.2 +/- microg/24 h in the group with zinc supplementation (p < 0.05). Insulin did not change in the placebo group, whereas there was a significant decrease of this hormone in the supplemented group. HOMA also decreased from 5.8 +/- 2.6 to 4.3 +/- 1.7 (p < 0.05) in the zinc-supplemented group but did not change in the placebo group. Leptin did not change in the placebo group. In the zinc group, leptin was 23.6 +/- 12.3 microg/L and did not change. More human data from a unique population of obese individuals with documented insulin resistance would be useful in guiding future studies on zinc supplementation (with higher doses or longer intervals) or different measures.

O Diabetes Mellitus do Tipo 2 favorece o aumento da morbidade e da mortalidade por doenças cardiovasculares. Essas doenças apresentam mesmo componente genético e mesmos antecedentes ambientais, sendo a resistência insulínica considerada um dos principais possíveis antecedentes. A síndrome metabólica é um transtorno complexo, representado por um conjunto de fatores de risco cardiovascular, usualmente relacionados à deposição central de gordura e à resistência à insulina. A modificação do comportamento alimentar inadequado e a perda ponderal, associadas à prática de atividade física regular, são consideradas terapias de primeira escolha para o tratamento da síndrome metabólica, por favorecer a redução da circunferência abdominal e da gordura visceral, melhorar a sensibilidade à insulina e diminuir as concentrações plasmáticas de glicose e triglicérides, aumentar os valores de HDL colesterol e, conseqüentemente, reduzir os fatores de risco para o desenvolvimento de Diabetes Mellitus do Tipo 2 e doenças cardiovasculares. Dessa forma, o presente artigo objetivou descrever e analisar alguns dos principais estudos publicados nas últimas décadas, os quais mostraram que a adoção de um estilo de vida adequado possibilita a prevenção primária do Diabetes Mellitus do Tipo 2. As mudanças no estilo de vida impróprio podem ser estimuladas por meio de uma intervenção educacional, dando ênfase ao aspecto nutricional e à atividade física, visando à redução dos fatores de risco relacionados à síndrome metabólica e às doenças cardiovasculares, em diferentes populações.

Body composition determined by dual energy x-ray absorptiometry and the abdominal visceral fat component determined by computed tomographic scanning were examined in women with Cushing's disease and compared with those in obese women with the same anthropometric parameters and those in nonobese women. Patients with Cushing's had no increase in total body fat or the trunk region (android) component, but had a higher intraabdominal fat area compared to the obese subjects. The total lean tissue mass was slightly reduced in Cushing's compared to that in the obese subjects due to a significant decrease in the muscle of the legs and arms; the reduced amounts of fat and lean tissue masses in the arms were the most significant findings in hypercortisolism. The body mineral and bone calcium contents were slightly reduced in Cushing's compared to those in the obese controls. Thus, although obese subjects had more fat and lean tissue and mineral masses than their normal weight counterparts, the Cushing's patients, with the same total fat mass and its components (except in the arms) as obese individuals, present total lean tissue and fractions, including body mineral and bone calcium contents, similar to those in nonobese subjects due to the depletion of the protein depots, as seen in hypercortisolism.

Diabetic retinopathy is a frequently observed complication in both type 1 and type 2 diabetes, specially in patients with long term disease and poor glicemic control. Irreversible visual loss appears at the final stages of diabetic retinopathy and it is considered one of the most tragic of diabetic complications. It is also considered an important factor of morbidity and has a high economical impact once it is the leading cause of blindness. The pathophysiology of the retinal microvascular alterations is related to the chronic hyperglycemia that leads to the following circulatory disturbances: loss of vascular tonus, increase in vascular permeability, edema and exudation, with vascular obstruction and ischemia that stimulates neovascularization, which may lead to fibrous retraction and vitreous hemorrhages with retinal detachment. Recent studies have indicated that the strict glicemic and blood pressure controls are effective in reducing or blocking the progression of retinopathy. Up to now no pharmacological agents have shown to be effective in preventing or reducing neovascularization and visual loss. Presently, the most effective available treatment for proliferative retinopathy is laser photocoagulation. Further studies are needed to obtain new products and technologies that could effectively prevent or block retinopathy progression.

The Brazilian Diabetes Society is starting an innovative project of quantitative assessment of medical arguments of and implementing a new way of elaborating SBD Position Statements. The final aim of this particular project is to propose a new Brazilian algorithm for the treatment of type 2 diabetes, based on the opinions of endocrinologists surveyed from a poll conducted on the Brazilian Diabetes Society website regarding the latest algorithm proposed by American Diabetes Association /European Association for the Study of Diabetes, published in January 2009.An additional source used, as a basis for the new algorithm, was to assess the acceptability of controversial arguments published in international literature, through a panel of renowned Brazilian specialists. Thirty controversial arguments in diabetes have been selected with their respective references, where each argument was assessed and scored according to its acceptability level and personal conviction of each member of the evaluation panel.This methodology was adapted using a similar approach to the one adopted in the recent position statement by the American College of Cardiology on coronary revascularization, of which not only cardiologists took part, but also specialists of other related areas.

BackgroundThere is increasing evidence to suggest that not all individuals with type 2 diabetes mellitus (T2DM) have equal risk for developing cardiovascular disease. We sought to compare the yield of testing for pre-clinical atherosclerosis with various approaches.Methods98 asymptomatic individuals with T2DM without known coronary artery disease (CAD) were enrolled in a prospective study and underwent carotid ultrasound, exercise treadmill testing (ETT), coronary artery calcium (CAC) scoring, and coronary computed tomography angiography (CTA).ResultsOf 98 subjects (average age 55 ± 6, 64 % female), 43 (44 %) had coronary plaque detectable on CTA, and 38 (39 %) had CAC score >0. By CTA, 16 (16 %) had coronary stenosis ≥50 %, including three subjects with CAC = 0. Subjects with coronary plaque had greater prevalence of carotid plaque (58 % vs. 38 %, p = 0.01) and greater carotid intima media thickness (0.80 ± 0.20 mm vs. 0.70 ± 0.11 mm, p = 0.02). Notably, 18 of 55 subjects (33 %) with normal CTA had carotid plaque. Eight subjects had a positive ETT, of whom five had ≥ 50 % coronary stenosis, two had <50 % stenosis, and one had no CAD. Among these tests, CAC scoring had the highest sensitivity and specificity for prediction of CAD.ConclusionAmong asymptomatic subjects with T2DM, a majority (56 %) had no CAD by CTA. When compared to CTA, CAC was the most accurate screening modality for detection of CAD, while ETT and carotid ultrasound were less sensitive and specific. However, 33 % of subjects with normal coronary CTA had carotid plaque, suggesting that screening for carotid plaque might better characterize stroke risk in such patients.

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The prevalence of Diabetes and Stress Hyperglycemia in the Acute Myocardial Infarction patients. Objectives: To evaluate in our population the real prevalence of diabetes (DM) and stress hyperglycemia (HE) in patients with myocardial infarction (IAM) admitted in a cardiologic emergency unit. Methods: A retrospective analysis of 2262 patients with AMI evaluating the prevalence of DM (referred and diagnosed) and stress hyperglycemia. Results: Besides 12,1% of subjects were previously referred to be diabetic (men: 10.7% and women: 15.8%), diabetes was effectively diagnosed in 24,8% (M: 22,9%, W: 29,7%) and stress hyperglycemia in 13,6% HE of the patients (M: 14,3%, W: 11,7%) indicating that glycemic alterations were effectively observed in 37.2.% of the patients with IAM (M: 37,2%, W: 41,4%). In DM subjects IAM events occurred earlier, total intra-hospital mortality was higher (DM: 20.7%, ND: 13,8%, HE: 13,4%) and less surgical procedures were performed (ND 33.8%, DM: 21.7%, HE: 18.0%). Conclusion: The elevated DM and stress hyperglycemia prevalence observed in our study indicates that glycemic alterations is one of the most important risk factors for IAM. (Arq Bras Endocrinol Metab 2008; 52/3:465-472)