Vitamin A does not influence mRNA expression of hormone hepcidin but other biomarkers of iron homeostasis in young male Wistar rats.

The effects of an adequate supply of vitamin A and iron, in comparison with diets low or absent in vitamin A and low in iron, on the mRNA expression of some biomarkers of iron homeostasis as hepcidin (Hamp), transferrin receptor-1 (Tfrc), iron regulatory protein-2 (Ireb2) and ferritin (Fth1) in rats were investigated. 35 male Wistar rats were randomly divided into 5 dietary groups: control, sufficient in iron and insufficient in vitamin A (FesvAi), sufficient in iron and depleted in vitamin A (FesvAd), insufficient in iron and sufficient in vitamin A (FeivAs) and insufficient in both iron and vitamin A (FeivAi). After 6 weeks rats showed no significant effects of variations in vitamin A on the expression of Hamp relative to the control group (FesvAi: 1.37-fold; FesvAd: 1.22-fold); however, iron deficiency showed significant reduction on it relative to the control group (FeivAs: 71.4-fold, P = 0.0004; FeivAi: 16.1-fold, P = 0.0008). Vitamin A deficiency (FesvAd) affects expression of Fth1 independent of low dietary iron in spleen (0.29-fold, P = 0.002) and duodenum (5.15-fold, P = 0.02). Variations of dietary iron and vitamin A showed significant effects relative to the control group for expression of Tfrc in spleen (FesvAd: 0.18-fold, P = 0.01; FeivAs: 0.24-fold, P < 0.0001; FeivAi: 0.42-fold, P = 0.014), Ireb2 in spleen (FeivAs: 3.7-fold, P < 0.0001; FeivAi: 2.9-fold, P < 0.0001) and Ireb2 in duodenum (FeivAs: 2.68-fold, P = 0.012; FeivAi: 2.60-fold, P = 0.014). These results show that vitamin A and iron must be supplied together to regulate some of the main biomarkers of iron metabolism as a strategy to reduce prevalence of iron deficiency anemia.

Classic and emergent indicators for the assessment of human iron status.

Iron deficiency is the leading cause of anemia, a significant global public health problem. Different methods exist for assessing iron nutritional status, including laboratory tests that focus on storage, transportation, and iron functional compartment parameters. Classical markers such as bone marrow, serum iron, ferritin, hemoglobin, erythrocyte parameters, transferrin, transferrin receptors, and zinc protoporphyrin are discussed in this review. Additional parameters calculated from these indicators, including transferrin saturation, ferritin index and Thomas plot, and some emergent parameters such as hepcidin, erythroferrone, and low hemoglobin density are also discussed. There is no a single indicator for assessing iron nutritional status. Therefore, the use of more than one indicator may be the best practice to obtain the correct diagnosis, also considering the influence of inflammation/infection on many of these indicators. The constant validation of the current parameters, the improvement of assessment methods, and the identification of new indicators will be the key to refine the assessment of iron nutritional status and the right choice of treatment for its improvement.

Vitamin A deficiency regulates the expression of ferritin in young male Wistar rats / A deficiência de vitamina A regula a expressão de ferritina em ratos Wistar machos jovens

ABSTRACT Objective Iron deficiency and vitamin A deficiency are two of the main micronutrient deficiencies. Both micronutrients are essential for human life and children's development. This study aimed to investigate the effects of vitamin A deficiency on ferritin and transferrin receptors' expression and its relationship with iron deficiency. Methods Five diets with different vitamin A-to-iron ratios were given to thirty five 21-day-old male Wistar rats (separated in groups of seven animals each). The animals received the diet for six weeks before being euthanized. Serum iron and retinol levels were measured as biochemical parameters. Their duodenums, spleens, and livers were analyzed for the expression of ferritin and transferrin receptors by Western Blotting. Results Regarding biochemical parameters, the results show that when both vitamin A and iron are insufficient, the serum iron content (74.74µg/dL) is significantly lower than the control group (255.86µg/dL). The results also show that vitamin A deficiency does not influence the expression of the transferrin receptor, but only of the ferritin one. Conclusion Vitamin A deficiency regulates the expression of ferritin in young male Wistar rats.

RESUMO Objetivo A deficiência de ferro e de vitamina A são duas das principais deficiências de micronutrientes, sendo que ambos são essenciais para a vida humana e o desenvolvimento das crianças. O objetivo deste estudo foi investigar o efeito da deficiência de vitamina A na expressão de ferritina e o receptor de transferrina e sua relação com a deficiência de ferro. Métodos Cinco dietas com diferentes proporções de vitamina A para ferro foram administradas a 35 ratos Wistar machos de 21 dias de vida (sete animais por grupo). Os animais receberam a dieta por seis semanas antes de serem eutanasiados. Os níveis séricos de ferro e retinol foram medidos como parâmetros bioquímicos. Duodeno, baço e fígado foram analisados quanto à expressão de ferritina e o receptor de transferrina por Western Blotting. Resultados Em relação aos parâmetros bioquímicos, os resultados mostram que quando a vitamina A e o ferro são insuficientes, o teor de ferro sérico (74.74µg/dL) é significativamente menor do que no grupo controle (255.86µg/dL). Os resultados também mostram que a deficiência de vitamina A não influencia a expressão do receptor da transferrina, mas da ferritina. Conclusão A deficiência de vitamina A regula a expressão de ferritina em ratos Wistar machos jovens.

Influence of Dietary Vitamin A and Iron Deficiency on Hematologic Parameters and Body Weight of Young Male Wistar Rats.

Micronutrient deficiency is one of the most prominent public health concerns; in particular, vitamin A and iron are determinants of appropriate development, and vitamin A influences iron homeostasis and metabolism. Here we compared the effects of diets that were sufficient and insufficient in vitamin A and iron on the hematologic parameters and body weight of rats. Male Wistar rats were randomly divided into 5 dietary groups (n = 7 per group): adequate in iron and vitamin A (control); adequate in iron but low in vitamin A (FesvAi); adequate in iron but lacking vitamin A (FesvAd); low in iron but adequate in vitamin A (FeivAs); and low in both iron and vitamin A (FeivAi). After 6 wk, rats showed significant differences in serum iron relative to the control diet (control, 256 ± 44 µg/dL; FesvAi, 220± 16 µg/dL; FesvAd, 181 ± 15 µg/dL; FeivAs, 131 ± 44 µg/dL; FeivAi, 75 ± 19 µg/dL). Rats on iron-deficient diets showed reduced Hgb values relative to the control diet (control, 15.9 ± 0.7 g/dL; FeivAs, 13.2 ± 1.6 g/dL; FeivAi, 12.9 ± 1.0 g/dL), MCV (control: 57 ± 10 fL; FeivAs, 48 ± 10 fL; FeivAi, 44 ± 3 fL), and Hct (control, 53% ± 2%; FeivAs, 44% ± 5%; FeivAi, 42% ± 8%). All of the experimental dietary groups showed significant differences in reticulocyte count when compared with the control group (control, 2.7% ± 2.2%; FesvAd, 0.6% ± 0.2%; FesvAi, 0.3% ± 0.1%; FeivAs, 1.2% ± 0.2%; FeivAi, 0.6% ± 0.5%). The mean difference in body weight for the experimental groups, relative to the control group, was 30 ± 10 g. These results suggested that, in young male Wistar rats, both iron and vitamin A are essential to cause increases in body weight and various hematologic parameters.

Composición de las oleorresinas de dos variedades de ají picante (habanero y tabasco) obtenidas mediante lixiviación con solventes orgánicos / Composition of oleoresins from two kinds of chili pepper (habanero and tabasco) obtained by lixiviation with organic solvents

Introducción. En el desarrollo de nuevos procesos e ingredientes para la industria alimentaria, las técnicas de extracción permiten obtener principios activos a partir de productos naturales, aptos para el consumo humano y fuertemente relacionados con la tendencia hacia una alimentación más saludable y libre de contaminantes. Las oleorresinas de especies vegetales permiten el manejo simultáneo de componentes pigmentantes y aromatizantes como en el caso de los pimientos, para los cuales la extracción con solventes orgánicos es una práctica común que debe refinarse de tal modo que se empleen sustancias de extracción seguras y aprobadas para el consumo humano. Objetivo. Comparar la composición de la oleorresina de dos variedades de ají picante (tabasco y habanero) extraída con dos solventes diferentes (hexano y acetato de etilo). Materiales y métodos. Se tomó material seco de dos variedades de ají picante (tabasco y habanero) y se sometieron a extracción con dos solventes orgánicos diferentes (hexano y acetato de etilo). Las oleorresinas resultantes fueron concentradas para calcular el rendimiento en extracción y luego fueron analizadas en un HPLC para determinar su contenido en capsaicina y dihidrocapsaicina. Resultados. Se encontró que el acetato de etilo es un mejor solvente que el hexano, pues presenta un porcentaje general de extracción del 11,23% frente a 7,14%. En la caracterización por HPLC se encontraron concentraciones aceptables de los principios pungentes (capsaicina y dihidrocapsaicina) las cuales corresponden con los valores teóricos en los cuales el ají habanero presenta entre 150.000 y 325.000 Unidades Scoville y tabasco presenta entre 50.000 y 100.000 Unidades Scoville. Conclusión. En un proceso de extracción con solventes sobre ají picante, se obtiene un mejor rendimiento en extracción empleando acetato de etilo como solvente y una mayor concentración de capsaicina y dihidrocapsaicina empleando ají habanero.

Introduction. In the development of new processes and ingredients for food industry, extraction techniques allow us to obtain active principles from natural products, good for human consuming and strongly related to the tendency towards a healthier and free of contaminants feeding. Oleoresins from vegetables allow us to work with dye and aromatic components (as in the case of peppers, for which, extraction with organic solvents is a common practice that must be refined in such a way that only safe and apt for human consumption substances are used). Objective. To compare the composition of oleoresin from two kinds of chili pepper (Tabasco and habanero) extracted with two different solvents (hexane and ethyl acetate). Materials and methods. Dry material from both kinds of chili pepper were taken and submitted to extraction with two different organic solvents (hexane and ethyl acetate). The oleoresins that resulted from this procedure were concentrated to calculate their performance in extraction and then analyzed in a HPLC to determine their contents of capsaicin and dihydrocapsaicin. Results. We found that ethyl acetate is a better solvent than hexane; it shows a general percentage of extraction of 11.23% compared to a 7.14%. In the characterization with the HPLC we found acceptable concentrations of the pungent principles (capsaicine and dihydrocapsaicin), corresponding to the theoretical values in which habanero pepper represents a value between 150000 and 325000 Scoville units and the Tabasco, between 50000 and 10000 Scoville units. Conclusion. In an extraction process for chili peppers, a better extraction performance is obtained by using ethyl acetate as solvent and a better concentration of capsaicin and dihydrocapsaicin by using habanero chili pepper.

Sustitución de colorantes en alimentos / Substitution of colorants in food

Los alimentos funcionales marcan las nuevas tendencias en producción y desarrollo del mercado. Entre ellos, los que tienen propiedades antioxidantes ocupan un importante segmento. Esto, unido a la necesidad de encontrar sustitutos para algunos ingredientes potencialmente tóxicos o alérgenos, obliga a la búsqueda permanente de productos naturales. En el caso de colorantes, el betacaroteno reúne dos propiedades importantes: es un poderoso antioxidante y a la vez posee poder pigmentante que varía desde el rojo hasta el amarillo. Se plantea la posibilidad de sustituir el colorante sintético tartrazina por uno igualmente sintético pero imitando al natural, el b-caroteno, evaluando su estabilidad y capacidad de pigmentación, además de sus potenciales propiedades funcionales.

Functional foods are the newest tendency in production and market development. Among them, those with antioxidant properties have a very important position. This, along with the fact that we need to find substitutes for some potentially toxic or allergenic ingredients, compels us to keep looking for natural products. In the case of colorants, betacarothene gathers two important characteristics: It is a powerful antioxidant and also has a coloring power from red to yellow. It is proposed to replace the synthetic colorant tartrazine with another synthetic but that imitates the natural, the bcarothene, evaluating its stability and coloring capability, and also its potential functional properties.