Associação entre índice glicêmico e carga glicêmica dietéticos e síndrome metabólica em idosos

OBJETIVO: Investigar a associação entre índice glicêmico (IG) e/ou carga glicêmica (CG) da dieta e síndrome metabólica (SM). MÉTODOS: Trata-se de estudo documental e do tipo caso-controle, com uma amostra de 229 idosos. Calcularam-se o IG e a CG, classificando-os em adequado (baixo) e inadequado (moderado e alto). Calculou-se ainda a prevalência de consumo dos alimentos, consumidos por pelo menos metade dos avaliados. A análise estatística dos dados foi efetuada por meio do teste c² e teste t de Student. Adotou-se p < 0,05 como nível de significância. RESULTADOS: Dos indivíduos estudados (n = 229), 74,2% pertenciam ao sexo feminino. A média de idade do grupo foi de 70,1 (6,4) anos. A média diária de IG do grupo caso foi de 62,3 (6,5), e do grupo controle de 62,1 (6,1), com p = 0,864. As médias diárias de CG não foram estatisticamente diferentes (p = 0,212), sendo a do grupo caso de 99,8 (33,8) e do grupo controle de 108,9 (45,7). Os alimentos consumidos tanto pelos casos como pelos controles, com maior contribuição ao IG, foram: pão, arroz, banana e açúcar refinado. CONCLUSÃO: No grupo avaliado, não houve associação entre índice glicêmico e carga glicêmica dietéticos e síndrome metabólica. O padrão identificado, no entanto, coloca portadores e não portadores em situação de risco à saúde, merecendo ações educativas.

Birth weight, current body mass index, and insulin sensitivity and secretion in young adults in two Latin American populations

Background and aims: Although studies have shown association of birth weight (BW) and adult body mass index (BMI) with insulin sensitivity in adults, there is limited evidence that BW is associated with insulin secretion. We assessed the associations between BW and current BMI with insulin sensitivity and secretion in young Latin American adults. Methods and results: Two birth cohorts, one from Ribeirao Preto, Brazil, based on 1984 participants aged 23-25 years, and another from Limache, Chile, based on 965 participants aged 22-28 years were studied. Weight and height at birth, and current fasting plasma glucose and insulin levels were measured. Insulin sensitivity (HOMA%S) and secretion (HOMA%beta) were estimated using the Homeostatic Model Assessment (HOMA2). Multiple linear regression analyses were carried out to test the associations between BW and adult BMI z-scores on log HOMA%S and log HOMA%beta. BW z-score was associated with HOMA%S in the two populations and HOMA%beta in Ribeirao Preto when adult BMI z-score was included in the model. BW z-score was associated with decreasing insulin secretion even without adjusting for adult BMI, but only in Ribeirao Preto. BMI z-score was associated with low HOMA%S and high HOMA%beta. No interactions between BW and BMI z-scores on insulin sensitivity were shown. Conclusions: This study supports the finding that BW may affect insulin sensitivity and secretion in young adults. The effect size of BW on insulin status is small in comparison to current BMI. (C) 2010 Elsevier B.V. All rights reserved.

Changes in renal glucose transporters in an animal model of metabolic syndrome

Considering the similarity between structural, hemodynamic, and functional changes of obesity-related renal disease and diabetic nephropathy, we hypothesized that renal glucose transporter changes occur in obesity as in diabetes. The aim of the work was to evaluate GLUT1 and GLUT2 in kidneys of an animal model of metabolic syndrome. Neonate spontaneously hypertensive rats (SHR), n=15/group, were treated with monosodium glutamate (5 mg/g) (MetS) for 9 days and compared with saline-treated Wistar-Kyoto (C) and SHR (H) rats. Lee index, systolic arterial pressure (SAP), glycemia, insulin resistance, triglycerides, and HDL cholesterol were evaluated at 3 and 6 months. Medullar GLUT1 and cortical GLUT2 were analyzed by Western blot. MetS vs. C and H rats had the highest Lee index (p<0.001) and insulin resistance (3-months C: 4.3±0.7, H: 3.9±0.9, MetS: 2.7±0.6; 6-months C: 4.2±0.6, H: 3.8±0.5, MetS: 2.4±0.6% • min−1, p<0.001), similar glycemia, and the lowest HDL-cholesterol at 6-months (p<0.001). In the MetS and H rats, SAP was higher vs. C at 3-months (p<0.001) and 6-months (C: 151±15, H: 190±11, MetS: 185±13 mm Hg, p<0.001) of age. GLUT1 was ̴ 13× lower (p<0.001) at 3-months, reestablishing its content at 6-months in MetS group, while GLUT2 was 2× higher (p<0.001) in this group at 6-months of age. Renal GLUT1 and GLUT2 are modulated in kidney of rats with metabolic syndrome, where obesity, insulin resistance and hypertension coexist, despite normoglycemia. Like in diabetes, cortical GLUT2 overexpression may contribute to the development of kidney disease