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Human bioavailability of curcumin from breads enriched with 1 g/portion of free curcumin (FCB), encapsulated curcumin (ECB), or encapsulated curcumin plus other polyphenols (ECBB) was evaluated. Parental and metabolized curcuminoids and phenolic acids were quantified by HPLC/MS/MS in blood, urine, and feces collected over 24 h. The concentrations of serum curcuminoids were always below 4 nmol/L and those of glucuronides 10-fold less. Encapsulation delayed and increased curcuminoid absorption as compared to the free ingredient. Serum and urinary concentrations of ferulic and vanillic acid were between 2- and 1000-fold higher than those of curcuminoids, with ECBB eliciting the highest amounts. Fecal curcuminoids were 6-fold more abundant after ECB than FCB, while phenolic acids after ECBB quadruplicated those after ECB. Curcuminoid encapsulation increased their bioavailability from enriched bread, probably preventing their biotransformation, with combined compounds slightly reducing this effect. Phenolic acids are the major metabolites of curcuminoids and may contribute to their biological properties.  相似文献   
254.
The DJ-1 gene encodes a ubiquitous, highly conserved protein. Here, we show that DJ-1 mutations are associated with PARK7, a monogenic form of human parkinsonism. The function of the DJ-1 protein remains unknown, but evidence suggests its involvement in the oxidative stress response. Our findings indicate that loss of DJ-1 function leads to neurodegeneration. Elucidating the physiological role of DJ-1 protein may promote understanding of the mechanisms of brain neuronal maintenance and pathogenesis of Parkinson's disease.  相似文献   
255.
The presence and function of CB2 receptors in central nervous system (CNS) neurons are controversial. We report the expression of CB2 receptor messenger RNA and protein localization on brainstem neurons. These functional CB2 receptors in the brainstem were activated by a CB2 receptor agonist, 2-arachidonoylglycerol, and by elevated endogenous levels of endocannabinoids, which also act at CB1 receptors. CB2 receptors represent an alternative site of action of endocannabinoids that opens the possibility of nonpsychotropic therapeutic interventions using enhanced endocannabinoid levels in localized brain areas.  相似文献   
256.
Apple is among the most consumed fruits worldwide, and several studies suggest that apple polyphenols could play a role in the prevention of degenerative diseases. 'Annurca' apple fruit undergoes, after harvest, a typical reddening treatment to turn the apples' skin red, and it is noted for its high firmness. This paper reports the effect of reddening-ripening treatment on polyphenol concentration and antioxidant activity of both peel and flesh extracts. The in vitro antioxidant properties have been compared with the protective effect against the cytotoxic effects of reactive oxygen species using Caco-2 cells as model system. Pretreatment of cells with different polyphenolic apple extracts provides a remarkable protection against oxidative damage. This effect seems to be associated with the antioxidant activity of 'Annurca' apple polyphenolic compounds. The flesh has antioxidant properties comparable to those possessed by the peel. Neither the reddening nor the fruit conservation causes changes in the antioxidant properties possessed by this apple variety. The data indicate that polyphenolic compounds in 'Annurca' apples are relatively stable in the peel and also in the flesh; therefore, the health benefits of polyphenols should be maintained during long-term storage. Finally, a diet rich in apple antioxidants could exert a beneficial effect in the prevention of intestinal pathologies related to the production of reactive oxygen species.  相似文献   
257.

Legumes and particularly beans are a key food of Mediterranean diet representing an important source of proteins, fiber, some minerals and vitamins and bioactive compounds. We evaluated the antioxidant and anti-mutagenic effects of a new fermented powder of a selected lectin-free and phaseolamin-enriched variety of common bean (Phaseolus vulgaris L.), named Lady Joy. Lady Joy lysate (Lys LJ) was studied in human erythrocytes and in Saccharomyces cerevisiae yeast cells. The antioxidant and anti-hemolytic properties of Lys LJ, studied in an ex vivo erythrocytes system using the cellular antioxidant assay (CAA-RBC) and the hemolysis test, evidenced a dose-dependent antioxidant activity as well as a significant hemolysis inhibition. Besides, results evidenced that Lys LJ treatment significantly decreased the intracellular ROS concentration and mutagenesis induced by hydrogen peroxide in S. cerevisiae D7 strain. In conclusion, Lys LJ showed both an antimutagenic effect in yeast and a strong scavenging activity in yeast and human cells.

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258.
Twenty-four multiparous Holstein cows were utilized in a completely randomized design to examine the effect of feeding field beans (FB, Vicia faba L. var. minor) as substitute for soybean meal (SBM) on lactation performance and metabolic response during the early lactation period. Cows were individually divided into two equal groups and fed for 16 weeks on one each of the two experimental diets. The controls were fed pelleted concentrate contained 150 g/kg dry matter (DM) of SBM as the main protein source, whereas the experimental concentrate contained 345 g/kg DM of FB. Oat hay was offered ad libitum to cows and water was freely available. Blood samples were assayed for their content of: urea, glucose, triglycerides, cholesterol, total protein, albumin, calcium and phosphorus, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA). Inclusion of FB had no detectable effects on DM intake (DMI), body weight (BW), or body condition score (BCS). Neither milk yield nor quality were influenced by dietary treatment, except for milk urea nitrogen (MU) that was reduced in cows fed the FB diet (P < 0.05). Clotting properties of milk were not affected adversely by added dietary FB. Concentration of blood urea (BU) was lower in cows fed the FB diet than in those fed the control SBM diet (P < 0.05). These findings indicate that feeding FB in a lactation diet supported lactation performance similar to cows fed traditional SBM-based diet, and the results may elicit great interest for countries where soybean utilization is adversely influenced by high supply costs.  相似文献   
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