Gas Chromatography-Triple Quadrupole Mass Spectrometry Analysis and Vasorelaxant Effect of Essential Oil from Protium heptaphyllum (Aubl.) March.

The Protium heptaphyllum species, also known as Almécega, produces an oily resin, used in folk medicine as an analgesic and anti-inflammatory agent, in healing, and as an expectorant, which is rich in pentacyclic triterpenes and essential oils. In this study, the essential oil obtained by hydrodistillation of Almécega's resin was analyzed by gas chromatography-triple quadrupole mass spectrometry and evaluated for chemical composition and vasorelaxant activity in rat superior mesenteric artery. The main constituents determined by gas chromatography-triple quadrupole mass spectrometry were limonene, p-cineole, and o-cymene. In intact rings precontracted with phenylephrine (Phe 1 µM), EOPh (3-750 µg/mL) induced relaxation, and the essential oil had a concentration-dependent vasorelaxant effect, without involvement of endothelial mediators.

Structural characterization of a Vatairea macrocarpa lectin in complex with a tumor-associated antigen: A new tool for cancer research.

Legume lectins are the most thoroughly studied group of lectins and have been widely linked to many pathological processes. Their use as immunohistochemistry markers for cell profiling and cancer diagnosis have made these molecules important tools for immunological studies and have stimulated the prospection and characterization of new lectins. The crystal structures of a recombinant seed lectin from Vatairea macrocarpa (rVML) and its complexes with GalNAcα1-O-Ser, GalNAc and α-lactose, have been determined at 1.90, 1.97, 2.70 and 1.83Å resolution, respectively. Small angle X-ray scattering and calorimetry assays have confirmed the same pH stable oligomerization pattern and binding profiles proposed for its wild-type counterpart. In silico analyzes have explored the potential of this recombinant lectin as new tool for cancer research through a comparative profile with other legume lectins widely used for cancer diagnosis and prognosis. The results suggest the recognition of specific epitopes exhibited on different cancer cells as a process that relies on the disposition of hydrophobic clusters and charged regions around the lectin carbohydrate-binding site, favouring the anchorage of different groups in the antigen boundaries, highlighting the different potential of each analyzed lectin. In conclusion, the experimental results and comparative analysis show that rVML is as a promising tool for cancer research, able to bind with high affinity specific tumor-associated antigens, highly stable and easily produced.

Structural basis of ConM binding with resveratrol, an anti-inflammatory and antioxidant polyphenol.

Resveratrol can also inhibit the activation of proinflammatory mediators and cytokines at the early gene expression stage. It is well known that lectins are sugar-binding proteins that act as both pro- and anti-inflammatory molecules. Thus, the objective of this work was to verify the binding of a polyphenol compound with a lectin of Canavalia maritima (ConM) based on their ability to inhibit pro-inflammatory processes. To accomplish this, ConM was purified and crystallized, and resveratrol was soaked at 5mM for 2h of incubation. The crystal belongs to the monoclinic space group C2, the final refinement resulted in an Rfactor of 16.0% and an Rfree of 25.5%. Resveratrol binds in the rigid ß-sheet through H-bonds and hydrophobic interaction with amino acids that compose the fifth and sixth ß-strands of the rigid ß-sheet of ConM. The ConM and resveratrol inhibited DPPH oxidation, showing synergic activity with the most effective ratio of 2:3 and carbohydrate binding site is not directly related to antioxidant activity. It is the interaction between ConM and resveratrol that indicates the synergism of these two molecules in acting as free radicals scavengers and in reducing the inflammatory process through the inhibition of many pro-inflammatory events.

Absorción de nutrientes en corderos alimentados con dietas con diferentes cantidades de fósforo / Nutrient absorption in lambs fed diets containing different amounts of phosphorus

Objective. Evaluate the effect of increasing P intake on nutrient digestibility, and compare the true and apparent absorption coefficients of P and Ca in lambs. Materials and methods. Twenty-four Santa Ines sheep, with an average weight of 33.6 ± 1.6 kg, were distributed into four treatments (0, 2, 4 and 6 g/day of supplementary P) with forage: concentrate ratio of 70:30. The study of apparent nutrient digestibility was conducted during the first week, using the total feces collection method. During the second week, after injection of 7.4 MBq of 32P and 7.7 MBq of 45Ca, apparent (AAC) and true (TAC) absorption coefficients of P and Ca were determined. The lambs were kept in metabolic cages. Results. The increase in P intake did not affect (p>0.05) dry matter, crude protein, NDF or ADF digestibility, but the TAC of P and Ca and mineral matter digestibility decreased. The AAC was not affected (p=0.10). A cubic relationship was observed between P intake and TAC (TAC=2.16–1.95X+0.55X2-0.04X3; R2=0.38) and linear relationship with the TAC of Ca (TAC=0.559–0.03X; R2=0.26). TAC and AAC values were different (p<0.001). Conclusions. The increase in P intake doesn’t impact organic matter digestibility, but does affect P and Ca absorption. Apparent digestibility is not a reliable parameter to determine the efficiency of P and Ca absorption.

Objetivo. Evaluar el efecto del incremento en la ingestión de P sobre la digestibilidad de los nutrientes, y comparar los coeficientes de digestibilidad real y aparente de Ca y P en ovinos. Materiales y métodos. Veinticuatro ovinos de la raza Santa Inés, con 33.6±1.6 kg de peso, fueron asignados a cuatro tratamientos (0, 2, 4 y 6 g/día de P suplementario) con relación forraje:concentrado de 70:30. El estudio de digestibilidad aparente de los nutrientes se realizó la primera semana usando el método de colecta total de heces. La segunda semana, luego de inyectar 7.4 MBq de 32P y 7.7 MBq de 45Ca, se realizó el estudio de absorción real (CAV) y aparente (AAC), en jaulas de estudio de metabolismo. Resultados. El incremento en la ingestión de P no afectó (p>0.05) la digestibilidad aparente de la materia seca, proteína bruta, FDN o FDA. El CAV de Ca y de P y la digestibilidad de la materia mineral presentaron una reducción. EL AAC no fue afectado (p=0.10). La ecuación CAV=2.16–1.95X+0.55X2-0.04X3 (R2 = 0.38) explicó la relación entre el CAV de P y el incremento en su ingestión, y la ecuación TAC=0.559 – 0.03X (R2=0.26), la relación entre el CAV de Ca y la ingestión de P. Los valores de AAC y CAV difirieron entre sí (p<0.001). Conclusiones. La ingestión de P no afectó la digestibilidad de la fracción orgánica del alimento, pero sí la absorción de P y Ca. El coeficiente de absorción aparente no fue un parámetro confiable para determinar la eficiencia de absorción de P y Ca.

Phosphorus concentration in sheep consuming increasing dietary levels of phosphorus / Concentração de fósforo em fluidos de ovinos em função da variação deste mineral na dieta / Concentración de fósforo en fluidos de ovinos en función de la variación del mineral en la dieta

Objective: the aim of this experiment was to evaluate the effect of increasing levels of P intake on the P concentration in biological fluids of Santa Ines lambs. Methods: 18 animals were individually confined in metabolic cages for 35 days. Phosphorus levels in the diet were: 25% lower than the level recommended by the NRC (1985) (T1); the recommended level by the same agency (T2); and 25% higher than the recommended level (T3). The experimental design was randomized blocks following a repeat measure arrangement. Two experimental periods of five weeks were evaluated. Saliva, plasma, rumen liquor, feces and urine samples for P determinations were collected during last three weeks of each period, for four consecutive days. Results: for the lowest amount of P intake (1.87 g/day) corresponding to T1 (p<0.05), showed values of plasma P in average of 5.99 mg/100 ml, 42.91 mg of P/100 ml in saliva, 48.64 mg of P/100 ml in ruminal liquor, 0.19 mg of P/kg PV in urine and 1.27 g/day in feces. Except for urine, all values were lower (p<0.05) than T2 and T3. Conclusion: these values can be considered as adequate to maintain the levels of P in the different fluids, and normal for a satisfactory animal performance, indicating that the NRC (1985) P recommended value could be reduced.

Objetivo: o objetivo deste trabalho foi avaliar o efeito do incremento na ingestão de P sobre a concentração do mineral em diferentes fluidos em cordeiros Santa Inês. Métodos: 18 animais foram mantidos em gaiolas de estudo de metabolismo por 35 dias. Os níveis de P nas dietas foram: 25% menos P que o recomendado pelo NRC (1985) (T1); quantidade recomendada pelo NRC (T2) e 25% a mais que o recomendado (T3). O delineamento experimental foi blocos casualizados em esquema de medidas repetidas. Foram avaliados dois períodos experimentais de cinco semanas cada. As amostras de saliva, plasma, conteúdo ruminal, fezes e urina, para a determinação do P foram coletadas durante as três últimas semanas, em quatro dias consecutivos. Resultados: a menor ingestão de P (p<0.05) correspondeu ao T1 (1.87 g/dia). No T1, foram observados níveis médios de 5.99 mg de P/100 ml no plasma, 42.91 mg de P/100 ml na saliva, 48.64 mg de P/100 ml no fluido ruminal, 0.19 mg de P/kg PV na urina e 1.27 g/dia de P nas fezes. Estes valores, com exceção da urina, foram menores (p<0.05) aos observados nos T2 e T3. Conclusões: estes valores podem ser suficientes para manter os níveis de P nos diferentes fluidos dentro de faixas consideradas normais para um bom desempenho animal, indicando que os valores de P recomendado pelo NRC (1985) poderiam ser reduzidos.

Objetivo: se evaluó el efecto del incremento en la ingestión de P sobre la concentración del mineral en diferentes fluidos de corderos Santa Inés. Métodos: 18 animales fueron mantenidos en jaulas de estudio metabólico por 35 días. Los niveles de P en las dietas fueron: 25% menos que lo recomendado el NRC (1985) (T1); cantidad recomendada por el NRC (T2) y 25% más de lo recomendado por el NRC (T3). El diseño experimental fue de bloques completamente al azar con medidas repetidas. Se evaluaron dos periodos experimentales de cinco semanas cada uno. Las muestras de saliva, plasma, contenido ruminal, heces y orina, para la determinación de P se tomaron durante las tres últimas semanas, en cuatro días consecutivos. Resultados: la menor ingestión de P (p<0.05) correspondió al T1 (1.87 g/día). En el T1 se observaron niveles medios de 5.99 mg de P/100 ml en plasma, 42.91 mg de P/100 ml en la saliva, 48.64 mg de P/100 ml en el fluido ruminal, 0.19 mg de P/kg PV en la orina y 1.27 g/día de P en las heces. Estos valores, con excepción de la orina, fueron menores (p<0.05) a los observados en T2 y T3. Conclusiones: los niveles observados pueden ser suficientes para mantener el P en los diferentes fluidos dentro de los rangos normales para un buen desempeño animal, indicando que los valores de P recomendados por el NRC (1985) podrían ser reducidos.