α-Linolenic acid prevents hepatic steatosis and improves glucose tolerance in mice fed a high-fat diet

OBJECTIVES: Dietary omega-3 fatty acids have been efficacious in decreasing serum cholesterol levels and reducing the risk of cardiovascular disease. However, the metabolic and molecular changes induced by the omega-3 fatty acid α-linolenic acid (ALA), which is found in linseed oil, are not fully understood. In this study, we showed a correlation between ALA and insulin resistance, inflammation and endoplasmic reticulum stress (ERS). METHODS: We studied 40 male mice (C57/BL6) divided into 4 groups: a control (C) group, a control + omega-3/ALA (CA) group, a high-fat diet (HFD) (H) group and a high-fat diet + omega-3/ALA (HA) group. For 8 weeks, the animals in the H and HA groups were fed a high-fat (60%) diet, while the animals in the C and CA groups received regular chow. The diets of the CA and HA groups were supplemented with 10% lyophilized ALA. RESULTS: ALA supplementation improved glucose tolerance and reduced insulin resistance, as measured by intraperitoneal glucose tolerance tests and the homeostasis model assessment for insulin resistance, respectively. In addition, ALA reduced hepatic steatosis and modified the standard fat concentration in the liver of animals fed an HFD. Dietary ALA supplementation reduced the serum levels of interleukin 6 (IL-6), interleukin 1 beta (IL-1β) and monocyte chemoattractant protein-1 (MCP-1), increased the expression of important chaperones such as binding immunoglobulin protein (BIP) and heat shock protein 70 (HSP70) and reduced the expression of C/EBP-homologous protein (CHOP) and X-box binding protein 1 (XBP1) in hepatic tissues, suggesting an ERS adaptation in response to ALA supplementation. CONCLUSIONS: Dietary ALA supplementation is effective in preventing hepatic steatosis; is associated with a reduction in insulin resistance, inflammation and ERS; and represents an alternative for improving liver function and obtaining metabolic benefits.

Cardiovascular risk in Japanese-Brazilian subjects / Risco cardiovascular em nipobrasileiros

OBJECTIVE: To evaluate the prevalence of risk factors for cardiovascular disease in Japanese-Brazilian subjects. SUBJECTS AND METHODS: One hundred thirty-one residents of the Mombuca community were studied. Statistical analysis was based on the X² test, Fisher's Exact test, Student's t test, and ANOVA, at a 5% significance level. RESULTS: The average age was 56.7 years-old; 76.3% had dyslipidemia, 24.4% pre-diabetes (PDM), 10.7% type 2 diabetes mellitus (T2DM), 46.6% hypertension, 52.7% abdominal obesity, and 35.8% metabolic syndrome (MS). There were significant correlations between HOMA-IR and MS diagnosis and obesity, while HOMA-β levels were decreased in T2DM and PDM. The ankle-brachial index was positive for peripheral artery disease in 22.3% of the individuals. Electrocardiograms did not show increased evidence of myocardial ischemia. CONCLUSION: Subjects of this community are exposed to major cardiovascular risk factors, namely high prevalence of MS diagnoses and increased HOMA-IR. Arq Bras Endocrinol Metab. 2012;56(9):608-13.

OBJETIVO: Avaliar a presença de fatores de risco para doença cardiovascular em nipo-brasileiros. SUJEITOS E MÉTODOS: Foram estudados 131 moradores de Mombuca. Utilizaram-se os testes do Qui-quadrado, Exato de Fisher, t de Student e ANOVA, com significância de 5%. RESULTADOS: A média de idade foi de 56,7 anos; 76,3% tinham dislipidemia, 24,4% pré-diabetes (PDM), 10,7% diabetes melito tipo 2 (DM2), 46,6% hipertensão, 52,7% obesidade abdominal e 35,8% síndrome metabólica (SM). Houve correlação significativa do HOMA-IR com SM e obesidade, enquanto HOMA-β esteve reduzido na presença de DM2 e PDM. O índice tornozelo-braquial foi positivo para doença arterial periférica em 22,3% dos indivíduos. O eletrocardiograma não mostrou aumento de isquemia miocárdica. CONCLUSÃO: A comunidade está exposta aos fatores de risco maiores para doença cardiovascular, o que pode ser resumido pela alta prevalência de diagnóstico de SM e valores elevados de HOMA-IR. Arq Bras Endocrinol Metab. 2012;56(9):608-13.

Intradermorreação de Montenegro após sucessivas repetições do teste em Porteirinha, MG / Montenegro intradermoreaction after the test sequential repetitions in Porteirinha, Minas Gerais State, Brazil

Para avaliar a resposta a sucessivas aplicaçöes da intradermorreaçäo de Montenegro (IDRM), repetimos quatro vezes o teste em moradores de uma área endêmica de calazar que tiveram o exame negativo há 3-4 anos. Inicialmente, repetimos três IDRM nos que permaneceram negativos, com intervalo de 60 dias entre elas. Na segunda etapa, realizamos uma última reaçäo em todos participantes do estudo. Do total de 49 indivíduos com IDRM prévia negativa, 19 (38,8 por cento) positivaram o teste em alguma das vezes, 17 (34,7 por cento) abandonaram o estudo e 13 (26,5 por cento) permaneceram com resultado negativo em todas as aplicaçöes. Na segunda etapa, a repetiçäo da IDRM mostrou que dos 14 que eram positivos em algum dos testes, 8 assim permaneceram e 6 tornaram-se negativos. Nossos resultados confirmam a possibilidade de induçäo de hipersensibilidade tardia em alguns indivíduos pela aplicaçäo da IDRM