Assessment of indicators of vitamin A status in non-cirrhotic chronic hepatitis C patients

Subjects with chronic liver disease are susceptible to hypovitaminosis A due to several factors. Therefore, identifying patients with vitamin deficiency and a requirement for vitamin supplementation is important. Most studies assessing vitamin A in the context of hepatic disorders are conducted using cirrhotic patients. A cross-sectional study was conducted in 43 non-cirrhotic patients with chronic hepatitis C to evaluate markers of vitamin A status represented by serum retinol, liver retinol, and serum retinol-binding protein levels. We also performed the relative dose-response test, which provides an indirect estimate of hepatic vitamin A reserves. These vitamin A indicators were assessed according to the stage of liver fibrosis using the METAVIR score and the body mass index. The sample study was predominantly composed of male subjects (63%) with mild liver fibrosis (F1). The relative dose-response test was <20% in all subjects, indicating vitamin A sufficiency. Overweight or obese patients had higher serum retinol levels than those with a normal body mass index (2.6 and 1.9 µmol/L, respectively; P<0.01). Subjects with moderate liver fibrosis (F2) showed lower levels of serum retinol (1.9 vs 2.5 µmol/L, P=0.01) and retinol-binding protein levels compared with those with mild fibrosis (F1) (46.3 vs 67.7 µg/mL, P<0.01). These results suggested an effect of being overweight on serum retinol levels. Furthermore, more advanced stages of liver fibrosis were related to a decrease in serum vitamin A levels.

Efficacy of the dietary histone deacetylase inhibitor butyrate alone or in combination with vitamin A against proliferation of MCF-7 human breast cancer cells

The combined treatment with histone deacetylase inhibitors (HDACi) and retinoids has been suggested as a potential epigenetic strategy for the control of cancer. In the present study, we investigated the effects of treatment with butyrate, a dietary HDACi, combined with vitamin A on MCF-7 human breast cancer cells. Cell proliferation was evaluated by the crystal violet staining method. MCF-7 cells were plated at 5 x 10(4) cells/mL and treated with butyrate (1 mM) alone or combined with vitamin A (10 µM) for 24 to 120 h. Cell proliferation inhibition was 34, 10 and 46% following treatment with butyrate, vitamin A and their combination, respectively, suggesting that vitamin A potentiated the inhibitory activities of butyrate. Furthermore, exposure to this short-chain fatty acid increased the level of histone H3K9 acetylation by 9.5-fold (Western blot), but not of H4K16, and increased the expression levels of p21WAF1 by 2.7-fold (Western blot) and of RARβ by 2.0-fold (quantitative real-time PCR). Our data show that RARβ may represent a molecular target for butyrate in breast cancer cells. Due to its effectiveness as a dietary HDACi, butyrate should be considered for use in combinatorial strategies with more active retinoids, especially in breast cancers in which RARβ is epigenetically altered.

Ausência de mutagenicidade e antimutagenicidade do extrato obtido das flores do ipê roxo [Tabebuia impetiginosa (Mart. ex DC.) Standl.] / Absence of mutagenicity and antimutagenicity of the extract obtained from the flowers of "ipê roxo" Tabebuia impetiginosa (Mart. ex DC.) Standl

A Tabebuia impetiginosa, conhecida popularmente como ipê-roxo, é uma planta nativa das florestas tropicais chuvosas da América do Sul e Central. Componentes químicos obtidos da casca têm mostrado efeito terapêutico, como antiinflamatório, antifúngico e antibacteriano. Porém, pela falta de dados na literatura, pouco se sabe sobre os efeitos do extrato das flores. Assim, o objetivo do presente trabalho foi avaliar o potencial mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa, em três diferentes concentrações (100, 300 e 500 mg kg-1 p.c.) pelo teste do micronúcleo. Para o teste de mutagenicidade, a doxorrubicina (DXR, 90 mg kg-1 p.c.) foi utilizada como indutor de danos no DNA e para o teste de antimutagenicidade, os tratamentos com o extrato foram realizados simultaneamente com este agente químico. O sangue periférico dos animais foi coletado 24 horas após os tratamentos. A comparação da frequência de eritrócitos policromáticos (PCEs) em 400 eritrócitos/animal entre os diferentes grupos não demonstrou qualquer citotoxicidade do extrato. Em relação às frequências de micronúcleos em PCEs (PCEMNs), não foram observadas diferenças significativas entre os grupos tratados com as diferentes concentrações de extrato e o controle negativo. Da mesma forma, todos os grupos de animais que receberam os tratamentos simultâneo do extrato (100, 300 ou 500 mg kg-1 p.c.) com a DXR, apresentaram valores de PCEMNs muito próximos quando comparados com os dados observados no grupo de animais que recebeu somente a DXR. Esses resultados apresentados indicam ausência de efeito mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa em sistema teste in vivo.

T. impetiginosa, known as "ipê-roxo", is a plant native to tropical rain forests of Central and South Americas. Chemical compounds obtained from its bark have shown anti-inflammatory, antifungal and antibacterial therapeutic effect. However, due to the lack of data in the literature, little is known about the effects of its flower extract. Thus, the aim of this study was to evaluate the mutagenic and antimutagenic potential of the extract obtained from T. impetiginosa flowers at three different concentrations (100, 300 and 500 mg kg-1 p.c.) by the micronucleus test. For the mutagenicity test, doxorubicin (DXR, 90 mg kg-1 p.c.) was used as DNA-damage inducer, while for the antimutagenicity test, treatments with the extract were performed simultaneously with this chemical agent. The peripheral blood of animals was collected 24 hours after the treatments. The frequency of polychromatic erythrocytes (PCEs) in 400 erythrocytes/animal was compared among the different groups and showed no extract cytotoxicity. As regards the frequency of micronuclei in PCEs (PCEMNs), there were no significant differences between the groups treated with different concentrations of extract and the negative control. Similarly, all groups of animals that received the simultaneous extract treatments (100, 300 or 500 mg kg-1 p.c.) with DXR showed very similar values of PCEMNs when compared with the data observed for the group of animals that received DXR alone. These results indicate no mutagenic and antimutagenic effect of the extract obtained from T. impetiginosa flowers in the testing system in vivo.

Water extracts of cabbage and kale inhibit ex vivo H2O2-induced DNA damage but not rat hepatocarcinogenesis

The chemopreventive potential of water extracts of the Brassica vegetables cabbage and kale was evaluated by administering their aqueous extracts in drinking water ad libitum to Wistar rats submitted to Ito’s hepatocarcinogenesis model (CB group and K group, respectively - 14 rats per group). Animals submitted to this same model and treated with water were used as controls (W group - 15 rats). Treatment with the vegetable extracts did not inhibit (P > 0.05) placental glutathione S-transferase-positive preneoplastic lesions (PNL). The number of apoptotic bodies did not differ (P > 0.05) among the experimental groups. Ex vivo hydrogen peroxide treatment of rat livers resulted in lower (P < 0.05) DNA strand breakage in cabbage- (107.6 ± 7.8 µm) and kale- (110.8 ± 10.0 µm) treated animals compared with control (120.9 ± 12.7 µm), as evaluated by the single cell gel (comet) assay. Treatment with cabbage (2 ± 0.3 µg/g) or kale (4 ± 0.2 µg/g) resulted in increased (P < 0.05) hepatic lutein concentration compared with control (0.5 ± 0.07 µg/g). Despite the absence of inhibitory effects of cabbage and kale aqueous extracts on PNL, these Brassica vegetables presented protection against DNA damage, an effect possibly related to increased hepatic lutein concentrations. However, it must be pointed out that the cause-effect relationship between lutein levels and protection is hypothetical and remains to be demonstrated.

Food intake and weight of lactating rats maintained on different protein-calorie diets, and pup growth

Studies on rats maintained on low-protein-calorie diets during the lactation period show that food intake decreases. This process results in weight loss and a delay in litter development. The purpose of the present study was to determine the alterations in food intake, maternal weight and litter growth during lactation when dams were exposed to diets with different levels os protein and carbohydrate. Female Wistar rats receiving one of 4 different diets, A (N = 14), B (N = 14), C (N = 9) and D (N = 9), were used. Diet A contained 16 per cent protein and 66 per cent carboydrate; diet B, 6 per cent protein and 77 per cent carboydrate; diet C, 6 per cent protein and 66 per cent carboydrate; diet D, 16 per cent protein and 56 per cent carboydrate. Thus, C and D diets were hypocaloric, while A and B were isocaloric. The intake of a low-protein diet in group B and C affected the weight of dams and litters during the last two weeks of lactation, while the low-calorie diets limited the growth of D litters at 21 days compared with A litters, but had no effect on the weight of D dams. Group B showed an increase in intake during the first five days of lactation, resulting in a behavioral calorie compensation due to the increase in carboydrate content, but the intake decreased during the last part of lactation. Food intake regulation predominantly involves the recruitment of a variety of peripheral satiety systems that attempt to decrease the central feeding command system.

Effect of zinc deficiency induced before and during pregnancy on the survival of female rats and their pups

The objective of the present study was to determine the consequences of Zn²+ deficiency on the gestational process. The study was conducted on adult Wistar virgin female rats fed isocaloric diets containing 16 percent protein and different Zn²+ concentrations, i.e., 2 ppm (severe restriction), 6 ppm (moderate restriction), and 20 ppm (control). Rats recived the diets and wather ad libitum for 7, 14 or 21 days before mating and throughout pregnancy. Survival of dams and pups decreased with increasing Zn²+ restriction and with time of exposure to the deficient diet. Mean survival rate for control dams and pups was 100 percent, whereas severe restriction (2 ppm for 21 days premating and during pregnancy) resulted in survival rates of 25 percent and 0 for dams and pus, respectively. Dam and pup survival rates for moderate restriction (6 ppm) for the same period were 83 percent and 72 percent, respectively. These results indicate the importance of Zn²+ before and during pregnancy and show that Zn²+ deficiency causes metabolic alterations which impair normal reproductive processes

Síndrome do intestino curto: aspectos fisiopatológicos, clínicos e suporte nutricional de longa duraçäo / Short bowel syndrome: physiopathological and clinical aspects, and long-term nutritional support

Os pacientes com Síndrome do Intestino Curto (SIC) necessitam de suporte nutricional parenteral, sem o que a taxa de mortalidade é superior a 80 por cento. A unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto mantém programa de suporte nutricional parenteral em regime ambulatorial para o paciente com SIC, estabelecido de acordo com a necessidade individual de cada paciente, o que é determinado pela avaliaçao periódica do estado nutricional por meio de critérios clínicos, dietéticos, antropométricos e bioquímicos. Este artigo discute os aspectos fisiopatológicos e clínicos da SIC, bem como a conduta do suporte nutricional de longa duraçao empregada nos pacientes tratados na Unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto.

Effect of acute glucose infusion on plasma levels of insulin, glucose and free fatty acids, and on the glucose removal rate in obese women

The objective of the present study was to report the variations in levels of insulin, free fatty acids and glucose occurring in a group of obese and nonobese women after acute intravenous glucose infusion. The difference between glucose and insulin levels in obese and nonobese women in response to glucose infusion was statistically significant. The mean maximum value for glucose detected in the obese group was 256 mg/dl versus 283 mg/dl in the nonobese group (p < 0.05). Insulin content was 147 muU/ml in the obese group versus 36 muU/ml in the nonobese group (p < 0.05). K (fractional removal rate constant for glucose) values were similar in both groups suggesting that the higher glucose and insulin peaks showed by the obese were due to the higher glucose uptake by the blood rather than its removal impairment.

Avaliacao antropometrica e bioquimica do estado nutricional. / Anthropometric and biochemical evaluation of nutritional status

A alteracao do estado nutricional e reconhecida como um dos graves problemas medicos especialmente nos paises em desenvolvimento sendo uma das preocupacoes da Nutrologia e avaliacao destas alteracoes. A presente revisao foi realizada com objetivo de apresentar e comentar alguns aspectos relacionados com a avaliacao antropometrica e bioquimica do estado nutriciona

Dietary supplementation and improvement in physical work performance of agricultural migrant workers of Southern Brazil.

Se llevo a cabo un ensayo de tres meses de duracion en l4 peones agricolas migrantes (Boias-Frias) residentes en la periferia de Ribeirao Preto, ciudad agricola e industrial situada en el interior del Estado de Sao Paulo en el sur del Brasil. Este grupo se puede considerar como marginalmente malnutrido. Su estado nutricional y rendimiento en el trabajo fisico se midio antes y despues de recibir un almuerzo suplementado durante el periodo mencionado.En ese lapso, el principal cambio observado en su estado nutricional fue un incremento del peso corporal. Segun mediciones practicadas utilizando la prueba de bicicleta con ergometro, su rendimiento en el trabajo fisico mejoro en forma significativa despues de la suplementacion de su dieta tradicional

Estudo de lipidogramas em pacientes do Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto (USP). / Lipidograms in patients of the Hospital das Clinicas of the Faculdade de Medicina de Ribeirao Preto (USP)

Foram realizados lipidogramas em 1.149 pacientes do Hospital das Clinicas de Ribeirao Preto. Neles foram encontrados 293 pacientes portadores de hiperlipidemias. Os resultados foram associados a diversas patologias, como hipertensao arterial, obesidade, nefropatia, diabetes mellitus, coronariopatia, acidente vascular cerebral e obstrucao arterial periferica. Entre os pacientes com lipidograma normal, 11,9% eram coronariopatas, 9,1% diabeticos e 3,9% eram nefropatas. Entre os pacientes com perfil lipidico alterado, 11,6% eram nefropatas, 13,3% diabeticos e 15,7% coronariopatas. Esses resultados foram semelhantes aos da literatura, considerando as coronariopatias, hipertensao arterial e nefropatias. Para os diabeticos e obesos, os dados do presente estudo diferem ligeiramente de outros trabalhos, mas demonstram mais uma vez a associacao entre essas patologias e alteracao do perfil lipidico

Estudo nutricional de pacientes hospitalizados. Ingestao alimentar em pacientes cirurgicos. / Nutrition of hospitalized patients. Food intake in surgical patients

Foram estudados 29 pacientes cirurgicos submetidos a gastrectomia e herniorrafia no Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, em relacao a ingestao de nutrientes nos periodos pre e pos-operatorios No periodo pre-operatorio, a maioria dos pacientes ingeriu uma quantidade de calorias abaixo das necessidades e 11 pacientes apresentaram tambem ingestao deficiente de proteinas. Proporcionalmente, a quantidade de gorduras e de glicides foi verificada estar elevada, desequilibrando a dieta. No periodo pos-operatorio, nenhum paciente apresentou consumo dos nutrientes que estivesse suprindo suas necessidades. Os autores fazem recomendacoes de maior atencao a prescricao dietetica dos pacientes e em particular aqueles submetidos a intervencoes cirurgicas