The aim of this study was to assess erythrocyte and plasma copper concentrations and correlate them with the lipid profile of overweight and obese children and adolescents. The study was performed with 15 overweight and 30 obese children and adolescents, and the results were compared to the control group (21), aged 6-16 yr. Anthropometric assessment was carried out using body mass index (BMI). Total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride serum levels were investigated. Erythrocyte and plasma copper levels were determined by atomic absorption spectrophotometry. Greater alterations in the lipid profile were observed in HDL-cholesterol, LDL-cholesterol, and triglyceride levels, with distinctions according to gender. The plasma copper concentrations in the overweight and obese male groups were significantly higher than those in the control group (p = 0.0006). Negative correlations between plasma copper and total cholesterol (r = -0.54) and LDL cholesterol (r = -0.59) were observed in the obese male group. There was no statistical difference in copper erythrocyte concentrations. The obesity associated to disorders in lipid metabolism predisposes to changes in copper plasma concentrations, but there was no alteration in intracellular reserves, which suggests an important homeostatic control to compensate for plasma oscillations and metabolic alterations of the disease.

The purpose of this study was to identify the effect of oral zinc supplementation in patients with type 1 diabetes (T1DM) on metabolic control and zinc blood concentrations. The sample consisted of 20 patients with T1DM and a control group (n=17). Metabolic control was evaluated by glycemia at fast, 24 h glycosuria, and HbA1c. Zinc concentrations were measured in plasma and erythrocytes. After the first collection of biological material, oral zinc supplementation was initiated and continued for 4 mo in T1MD patients (T1). Daily dosages were established based on Dietary Recommended Intakes (DRIs), considering zinc intake based on data from other studies previously performed with this population. All analyses were repeated after supplementation (T2). Metabolic control was unsatisfactory, with an HbA1c increase at T2. There was no difference in zinc concentrations in plasma and erythrocytes between patients with T1DM and control. Zinc concentrations in plasma were within the normal range in T1MD before and after supplementation and the control. Zinc concentrations in erythrocyte presented lower than normal values for all groups. A zinc increase in erythrocyte after supplementation was observed in T1DM patients, although without statistical significance. More studies are needed to confirm oral zinc supplementation as nutritional management in diabetes.

This ELISA represents a very practical tool for measuring LDL(-) in human blood for widespread research and clinical sample use.

O zinco apresenta funções catalíticas, estruturais e reguladoras, sendo componente de várias enzimas. Os sintomas observados na deficiência deste elemento incluem lesões de pele, anorexia, retardo do crescimento, hipogonadismo e alteração na função imune. O objetivo desta revisão foi apresentar as funções metabólicas e funcionais do zinco, enfatizando as conseqüências da deficiência e os aspectos que justificam os estudos envolvendo a suplementação com zinco e seus efeitos sobre o crescimento, sistema imunológico e diabetes. Considerando que algumas doenças predispõem o organismo à deficiência de zinco, a suplementação, isoladamente ou associada a outros elementos, demonstra benefícios, especialmente no aumento da velocidade de crescimento, funcionamento do sistema imunológico, diminuição das afecções respiratórias e controle das diarréias. A suplementação em pacientes com diabetes está relacionada com as variáveis do controle metabólico e as concentrações plasmáticas e eritrocitárias de zinco. As estratégias de suplementação com zinco, em populações de risco, devem ser implementadas, considerando-se as doses adequadas de ingestão. Termos de indexação: crescimento, diabetes, sistema imunológico, suplementação, zinco. A B S T R A C T Zinc has catalytic, structural and regulatory functions and is a component of many enzymes. Skin lesions

572Arq ABSTRACT Effect of Zinc Supplementation on Urinary Zinc Excretion of Patients With Type 1 Diabetes.The effect of oral zinc (Zn) supplementation was investigated in children and adolescents with type 1 diabetes (DM1), evaluating their metabolic control and urinary Zn concentrations. Twenty DM1 patients were compared with a control group (n=17); the metabolic control included fasting glucose levels, 24h urinary glucose levels and HbA1c. Zn concentrations were measured in 24h urine before (T1) and after (T2) supplementation. DM1 patients were given oral supplements of tasteless bis-glycine chelated Zn during a 4 month period after the initial collection of baseline data. Doses were established based on the Dietary Reference Intakes. The results demonstrated unsatisfactory metabolic control due to higher HbA1c levels in some patients, after Zn supplementation. Urinary Zn excretion was higher in DM1 patients and disclosed a positive correlation with disease duration and HbA1c levels. Zn supplementation did not correct the heterogeneity of circadian variation in the studied patients, suggesting that inadequate metabolic control in DM may cause disturbances in Zn metabolism, regardless of the dietary or supplemental source.