Neutrotoxic effects of fructose administration in rat brain: implications for fructosemia.

Fructose accumulates in tissue and body fluids of patients affected by hereditary fructose intolerance (HFI), a disorder caused by the deficiency of aldolase B. We investigated the effect of acute fructose administration on the biochemical profile and on the activities of the Krebs cycle enzymes in the cerebral cortex of young rats. Rats received a subcutaneous injection of NaCl (0.9 %; control group) or fructose solution (5 µmol/g; treated group). Twelve or 24 h after the administration, the animals were euthanized and the cerebral cortices were isolated. Peripheral blood (to obtain the serum) and cerebral spinal fluid (CSF) from the animals were also collected. It was observed that albumin levels were decreased and cholesterol levels were increased in CSF of animals 12 h after the administration of fructose. In addition, serum lactate levels were increased 12 h after the administration, as compared to control group. Furthermore, malate dehydrogenase activity was increased in cerebral cortex from treated group 24 h after the administration of this carbohydrate. Herein we demonstrate that fructose administration alters biochemical parameters in CSF and serum and bioenergetics parameters in the cerebral cortex. These findings indicate a possible role of fructose on brain alterations found in HFI patients.

Evaluation of the In Vivo and In Vitro Effects of Fructose on Respiratory Chain Complexes in Tissues of Young Rats.

Hereditary fructose intolerance (HFI) is an autosomal-recessive disorder characterized by fructose and fructose-1-phosphate accumulation in tissues and biological fluids of patients. This disease results from a deficiency of aldolase B, which metabolizes fructose in the liver, kidney, and small intestine. We here investigated the effect of acute fructose administration on the activities of mitochondrial respiratory chain complexes, succinate dehydrogenase (SDH), and malate dehydrogenase (MDH) in cerebral cortex, liver, kidney, and skeletal muscle of male 30-day-old Wistar rats. The rats received subcutaneous injection of sodium chloride (0.9%; control group) or fructose solution (5 µmol/g; treated group). One hour later, the animals were euthanized and the cerebral cortex, liver, kidney, and skeletal muscle were isolated and homogenized for the investigations. Acute fructose administration increased complex I-III activity in liver. On the other hand, decreased complexes II and II-III activities in skeletal muscle and MDH in kidney were found. Interestingly, none of these parameters were affected in vitro. Our present data indicate that fructose administration elicits impairment of mitochondrial energy metabolism, which may contribute to the pathogenesis of the HFI patients.

Perfil lipídico e a sua relação com fatores de risco cardiovascular em estudantes de nutrição / Lipid profile and its relationship to cardiovascular risk factors in nutrition students

As dislipidemias representam um dos fatores de risco cardiovascular mais bem estudados. Uma vez que as principais causas das dislipidemias são modificáveis, a identificação dos fatores de risco representa o melhor meio para estabelecer estratégicas de prevenção. Objetivos: Verificar o perfil lipídico de estudantes de nutrição e a sua relação com outros fatores de risco cardiovascular. Métodos: Foram avaliados 63 estudantes de nutrição, do sexo feminino, com idade entre 17 anos e 43 anos. Os dados foram obtidos por meio de coleta sanguínea, medidas antropométricas e aplicação de questionários. Resultados: A idade média das estudantes foi 22,4 (DP=5,32) anos. Os fatores de risco cardiovascular mais prevalentes foram: sedentarismo (81 por cento), antecedentes familiares (65,1 por cento) e uso de contraceptivo oral (52,4 por cento). Embora o perfil lipídico da amostra tenha se mostrado predominantemente favorável, verificou-se HDL...

The effect of N-acetylcysteine supplementation upon viral load, CD4, CD8, total lymphocyte count and hematocrit in individuals undergoing antiretroviral treatment.

Individuals infected with the human immunodeficiency virus (HIV-1) present with decreased CD4, a progressive increase in viral load, compromised cell immune defense, and hematologic alterations. The aim of this study was to assess the serum viral load, CD4, CD8, lymphocyte count and hematocrit at the beginning of antiretroviral therapy in individuals who were supplemented with N-acetylcysteine (NAC). Twenty volunteers participated in this double-blind, placebo-controlled 180-day study. Ten participants received 600 mg of NAC per day (NAC group) and the other ten serving as a control group received placebo. The above mentioned parameters were determined before treatment, and after 60, 120 and 180 days. In NAC-treated patients hematocrit remained stable and an increase in CD4 cell count took place earlier than that in the control group.

An evaluation of antiretroviral therapy associated with alpha-tocopherol supplementation in HIV-infected patients.

In HIV-infected patients, an increase in the production of oxygen-reactive species (ROS) is observed, with a consequent reduction of plasma levels of antioxidants such as alpha-tocopherol. The nuclear transcription factor-kappaB (NF-kappaB) is activated by a prooxidant state in the infected T cells through the release of its inhibitory subunit I-kappaB. The aim of the present work was to evaluate the behavior of hematological parameters and markers of anemia in HIV-infected patients who underwent antiretroviral therapy associated with 800 mg/day alpha-tocopherol supplementation. Blood samples were collected from supplemented (n=9) and not-supplemented (n=9) HIV-seropositive patients (n=18). We observed a decreased viral load in the alpha-tocopherol-supplemented group (p<0.05); other changes, such as an increase in the CD4/CD8 ratio, in the hematocrit and in the hemoglobin concentration were also observed, though lacking statistical significance. We conclude that antiretroviral therapy in association with alpha-tocopherol (800 mg/day) supplementation is more effective in reducing viral load levels and also, possibly, in recovering other hematological parameters after a 60-day period of use.