Rhamnogalacturonan II is a Toll-like receptor 4 agonist that inhibits tumor growth by activating dendritic cell-mediated CD8+ T cells

We evaluated the effectiveness of rhamnogalacturonan II (RG-II)-stimulated bone marrow-derived dendritic cells (BMDCs) vaccination on the induction of antitumor immunity in a mouse lymphoma model using EG7-lymphoma cells expressing ovalbumin (OVA). BMDCs treated with RG-II had an activated phenotype. RG-II induced interleukin (IL)-12, IL-1beta, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) production during dendritic cell (DC) maturation. BMDCs stimulated with RG-II facilitate the proliferation of CD8+ T cells. Using BMDCs from the mice deficient in Toll-like receptors (TLRs), we revealed that RG-II activity is dependent on TLR4. RG-II showed a preventive effect of immunization with OVA-pulsed BMDCs against EG7 lymphoma. These results suggested that RG-II expedites the DC-based immune response through the TLR4 signaling pathway.

Uso de Passiflora edulis f. flavicarpa na redução do colesterol / Use of Passiflora edulis f. flavicarpa on cholesterol reduction

A farinha da casca de maracujá é rica em uma fibra solúvel chamada pectina. Para avaliar o efeito dessa farinha na redução do colesterol foi realizado um estudo clínico piloto com dezenove mulheres, com idade entre 30 e 60 anos e apresentando hipercolesterolemia (colesterol > 200 mg/dL). Elas foram tratadas diariamente com 30 g da farinha da casca de maracujá por 60 dias. Após esse tempo foi observada uma redução estatisticamente significante (p < 0,05) nos níveis colesterol total (p = 0,00000) e colesterol LDL (p = 0,01193). Os resultados sugerem que a farinha da casca de maracujá seja utilizada na alimentação humana, juntamente com os alimentos, ou como matéria prima na produção de outros produtos, com o objetivo de reduzir o colesterol.

The flour of the passion fruit peel is rich in a soluble fiber called pectin. In order to evaluate the effect of this flour on cholesterol reduction, a pilot clinical study, was carried out with nineteen women, aged between 30 and 60 years, all of whom presented high cholesterol level (cholesterol > 200 mg/dL). The treatment consisted of daily doses of 30 g of the flour during 60 days. At the end of the 60 days it was observed a statistical reduction (p < 0.05) of the total cholesterol (p = 0,00000) and LDL-cholesterol (p = 0,01193) levels. The results suggested that the passion fruit peel flour, rich in pectin, can be used in human diet, with a large variety of foods, or as a raw material for other products intending to reduce cholesterol levels.

Viscosity of gums in vitro and their ability to reduce postprandial hyperglycemia in normal subjects

Experiments were carried out in vitro with three viscous polysaccharides (guar gum, pectin, and carboxymethylcellulose (CMC) of similar initial viscosity submitted to conditions that mimic events occurring in the stomach and duodenum, and their viscosity in these situations was compared to their actions on postprandial hyperglycemia in normal human subjects. Guar gum showed greater viscosity than the other gums during acidification and/or alkalinization and also showed larger effects on plasma glucose levels (35 per cent reduction in maximum rise in plasma glucose) and on the total area under the curve of plasma glucose (control: 20,314 + 1007 mg dl(-1) 180 min (-1) vs guar gum: 18,277 + 699 mg dl(-1) 180 min (-1), P<0.01). Pectin, which showed a marked reduction in viscosity at 37 degrees Celsius and after events mimicking those that occur in the stomach and duodenum, did not have a significant effect on postprandial hyperglycemia. The performance of viscosity and the glycemia response to CMC were at an intermediate level between guar gum and pectin. In conclusion, these data suggest that temperature, the process of acidification, alkalinization and exposure to intestinal ions induce different viscosity changes in gums having similar initial viscosity, establishing a direct relationship between a minor decrease of gum viscosity in vitro and a reduction of postprandial hyperglycemia.

Efeito da fibra alimentar sobre os níveis de colesterol, HDL-Colesterol e Triaciglicerol Serico / Effect of the fiber ingestion over the cholesterol, HDL-Cholesterol and Triglyceride

Foi avaliado o efeito da fraçao fibra (pectina e lignina)e fonte de fibra (fibrax) em dietas ricas ou pobres em colesterol sobre os níveis séricos de colesterol, HDL-COL, e triacilglicerol de ratos. Foram aplicados 8 tipos de raçöes: 2 grupos controle (sem fibra, com ou sem a adiçao de 1g por cento de colesterol) e 6 grupos testes (com 5g por cento de lignina ou 5g por cento de pectina ou 10g por cento de fibrax, com ou sem adiçäo de 1g por cento de colesterol). O experimento foi realizado por 42 dias, utilizando 56 ratos. Ao final desse período, os ratos foram anestesiados e coletado o sangue por punçäo cardíaca. Pectina baixou o colesterol sérico, porém quando a dieta era rica em colesterol apresentou baixos níveis de HDL-COL. Lignina com colesterol dietético baixou o colesterol e HDL-COL sérico. Fibrax aumentou o colesterol sérico, porém baixou o triacilglicerol quando era adicionado colesterol dietético na raçäo. Dieta rica em colesterol, obteve menor nível de HDL-COL, em dietas isenta de fibra alimentar.

Nutrient interaction in relation to glycaemic and insulinaemic response.

Although it is known that protein, fat and fibre reduce the postprandial glycaemia following an oral carbohydrate load, the nature and extent of interaction of different nutrients with one another in this respect is not well understood. The present study was designed to explore systematically the glycaemic and insulinaemic response to glucose (G) alone, or in combination with one or more of the following: casein (CS), maize oil (MO), cellulose (CL) and pectin (P). Besides 100 g G, eleven isoenergetic and six isocarbohydrate meals were studied on healthy adult males using an incomplete block design. Addition of other nutrients to G led to a lowering of the glycaemic response. The lowest glycaemic responses were seen in case of meals containing the largest number of nutrients. P was more effective in reducing postprandial glycaemia than CL. As in case of glycaemic response, low insulinaemic responses were also associated with P-containing meals, and meals containing the largest number of nutrients. But unlike in case of glycaemic response, there was a tendency for elevation of the insulinaemic response in case of CL-containing meals. The degree of attenuation of glycaemic response observed with meals containing several nutrients was roughly predictable on the basis of the attenuation observed with meals in which only one nutrient had been added at a time to G. But the glycaemic response of natural foods is unlikely to be predictable on the basis of their nutrient composition because of the overriding influence of several other factors such as physical form, cooking, processing, storage and antinutrient content of the food.

Modulation of postprandial glycaemia and insulinaemia by pectin in mixed nutrient combinations.

The present study was designed to examine the effect of pectin (P) on postprandial glycaemia and insulinaemia when ingested with glucose (G), casein (Cs) and corn oil (Co) in various combinations. The study was conducted on five healthy male volunteers, on each of whom five meal tolerance tests were performed. The meals were isocaloric and consisted of G; G and P; G, Cs and P; G, Co and P; and G, Cs, Co and P. The meals were administered after an overnight fast. In addition to a fasting blood sample, blood was collected 0.5, 1.0, 1.5 and 2.0 h after ingestion for measurement of serum glucose and insulin levels. The glycaemic and insulinaemic response to GP did not differ significantly from that to G. All the other meals, viz. GCsP, GCoP and GCsCoP, gave a significant reduction in postprandial glycaemia as compared to G. The corn oil containing meals, viz. GCoP and GCsCoP, in addition, gave a significant reduction in postprandial insulinaemia as compared to G. Pectin alone is not a dependable dietary constituent for reducing postprandial glycaemia. Its combination with protein and fat significantly lowers the postprandial glycaemic as well as insulinaemic response to orally administered glucose.

Açäo da fibra solúvel - pectina - sobre os níveis glicêmicos em ratos / Action of the soluble fiber - pectin - upon the glucose levels in rats

O presente trabalho tem como objetivo verificar a açäo da fibra solúvel - pectina - sobre os níveis de glicose sangüínea em ratos normais e diabéticos. Raçöes à base de caseína, adicionada de pectina cítrica comercial, em concentraçöes de 1%, 2% e 4%, foram administradas a ratos machos e adultos da linhagem "Wistar", diabéticos. A diabetes foi induzida nos animais com aloxana, por via intravenosa. Foi realizada a análise de composiçäo centesimal das raçöes, discriminando os componentes da fraçäo "fibra da dieta". Os níveis de glicose, triglicerídeos, colesterol, colesterol HDL e lípides totais sangüíneos foram determinados. Foi observada uma açäo hipoglicemiante nos animais alimentados com raçöes adicionadas de pectina, nos três níveis testados

Efecto nutricional de la pectina en cerdos en crecimiento y terminación / Nutritional effect of pectin in swines in growing and finishing periods

Se investigó el efecto nutricional que la administración de dietas adicionadas de 2 y 4% de pectina proveniente de cítricos produce en el cerdo. Se utilizaron 40 cerdos, divididos en los grupos de tratamiento, los que fueron alimentados con dietas con y sin pectina, durante los períodos de crecimiento y terminación. En todos los animales se midió el espesor de la grasa dorsal antes del sacrificio (103 + ou - 1.5 kg). La adición de 2% de pectina en cerdos con un peso vivo promedio de 41 y hasta de 70 kg, produjo una disminución de 6 y 3% en la ganancia ponderal diaria, así como en el índice de conversión alimenticia, respectivamente. La adición de 4% de pectina sobre un peso vivo promedio de 71 y hasta de 103 kg, indujo un incremento altamente significativo (P <0.01) en la ganancia ponderal diaria de 125g (15%), sin modificar en índice de conversión. El promedio de espesor de la grasa dorsal en los cerdos del grupo de tratamiento con pectina fue 2 mm (8%) menor que en los del grupo control. En conclusión, se puede decir que el consumo de pectina en el período de terminación del cerdo mejoró la ganancia diaria de peso, sin afectar la eficiencia alimenticia. Ello permitió la obtención de animales de mejor calidad, ya que disminuyó el espesor de la grasa dorsal

Hypocholesterolaemic effects of dietary fibre.

Role of dietary fibre in lowering serum cholesterol has been studied in mongrel dogs. Pectin, wheat bra, guar gum and Isabghol were fed with standard diet. No statistically significant changes were found in serum cholesterol levels in any groug (P greater than .05) after one week. Later by 15th day, pectin reduced serum cholesterol significantly i.e. 12.4% (P less than .02). However, in groups being fed other forms of fibre the levels of serum cholesterol were reduced by 3.8% to 7.0