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Pre-peptide regions of secreted proteins display wide sequence variability, even among highly homologous proteins such as coagulation factors, and are intracellularly removed, thus potentially favoring secretion of wild-type proteins upon suppression of nonsense mutations (translational readthrough). As models we selected F9 nonsense mutations with readthrough-favorable features affecting the pre-peptide and pro-peptide regions of coagulation factor IX (FIX), which cause hemophilia B (HB). Only the p.Gly21Ter (c.61G > T) in the variable pre-peptide hydrophobic core significantly responded (secretion, 4.1 ± 0.5% of wild-type; coagulant activity, 4.0 ± 0.3%) to the readthrough-inducer geneticin. Strikingly, for the p.Gly21Ter mutation, the resulting specific coagulant activity (0.96 ± 0.11) was compatible with normal function, thus suggesting secretion of FIX with wild-type features upon readthrough and removal of pre-peptide. Expression of the predicted readthrough-deriving missense variants (Gly21Trp/Cys/Arg) revealed a preserved specific activity (ranging from 0.84 to 0.98), thus supporting our observation. Conversely, rescue of the p.Cys28Ter (c.84T > A) and p.Lys45Ter (c.133A > T) was prevented by constraints of adjacent cleavage sites, a finding consistent with the association of most missense mutations affecting these regions with severe or moderate HB. Overall, our data indicate that suppression of nonsense mutations in the pre-peptide core preserves mature protein features, thus making this class of mutations preferred candidates for therapeutic readthrough.

In this study the antioxidant composition of fresh and stored strawberries and the bioavailability of the main strawberry bioactive compounds were determined in humans. In addition we have investigated plasma total antioxidant capacity. On 13 healthy volunteers, blood samples were collected before and after acute ingestion of fresh and stored strawberries, 300g respectively. Ferric Reducing Antioxidant Power (FRAP) values after consumption of fresh and stored strawberries showed a significant increase (P < 0.05) at 5 and 8 hours time interval, while significantly decreased TRAP (Total Radical-Trapping Antioxidant Parameter) values (P < 0.05) were found at 8 hours respect to baseline after stored strawberries consumption. After consuming fresh strawberries, plasma levels of α-carotene increased significantly (P < 0.05) respect to stored ones. Moreover, consumption of fresh and stored strawberries resulted in a significant increase of vitamin C at 2, 3 and 5 hours (P < 0.05). The bioavailable amount of strawberries antioxidant compounds reflects the variations observed in fresh and stored fruits. We could summarize that the global food quality is related to both native quantity of bioactive compounds and storage treatments.

Plant-based foods (such as fruit and vegetables, wine, nuts, natural vegetable oils, and whole grains) are an important component of traditional diets in Mediterranean regions. A large, consistent body of scientific evidence demonstrates that diets rich in plant foods provide protection against degenerative diseases; however, despite the consensus of the evidence about the health effect of plant foods, it is unclear which components of plant-based foods are protective and what their mechanism of action is. One of the hypotheses postulated to explain the protective effect of plant food, the antioxidant hypothesis, is based on their high content of bioactive molecules. Recent evidence suggests that it is the variegate composition of the plant food, an optimal mixture of different antioxidants endowed with complementary mechanism of action and different redox potential, which is at the basis of their effect on health. The global antioxidant efficiency of complex matrixes can be assessed by measuring their total antioxidant capacity (TAC) representing the result of variables such as redox potentials of the compounds present in the matrix and their cumulative and synergistic interaction. In the last years different databases for TAC of plant foods have been developed. Results suggest that coffee might represent a potential contributor to dietary antioxidant intake. In this contribution after describing the main contributors to dietary TAC for different plant food group, we will discuss the potentiality of coffee as a source of "ready to drink" reducing equivalents.

The antioxidant properties of dietary phenolics are believed to be reduced in vivo because of their affinity for proteins. In this study we assessed the bioavailability of phenolics and the in vivo plasma antioxidant capacity after the consumption of blueberries (Vaccinium corymbosum L.) with and without milk. In a crossover design, 11 healthy human volunteers consumed either (a) 200 g of blueberries plus 200 ml of water or (b) 200 g of blueberries plus 200 ml of whole milk. Venous samples were collected at baseline and at 1, 2, and 5 h postconsumption. Ingestion of blueberries increased plasma levels of reducing and chain-breaking potential (+6.1%, p

International audience; The present study investigated the effect of the consumption of two cheese varieties differing for fat quality on blood lipid profile and redox status biomarkers in 30 selected healthy volunteers, consuming either the experimental cheese (from milk produced by cows fed a grass and maize silage based diet with 5% of linseed oil added) or the control cheese (from normal cows' milk) for 4 weeks according to a crossover design. The experimental cheese had a lower content of medium-chain saturated fatty acids and a higher content of stearic acid and polyunsaturated fatty acids; its consumption led to higher levels of vitamins C and E and stearic acid in blood, while myristic acid and oxidized low-density lipoprotein concentrations were significantly lower. As myristic acid and oxidized low-density lipoprotein are highly correlated with increased atherogenic risk and vitamins C and E with antioxidant activity, the enrichment of cows' diet with linseed oil could provide a dietary option to prevent cardiovascular diseases risk.

The aim of the study was to assess the effect of drinking rooibos tea (Aspalathus linearis) on total antioxidant capacity (TAC), lipid triacylglycerols, cholesterol and glycaemia plasma levels in humans. In vitro, unfermented rooibos tea displayed a 28% higher value of TRAP than did the fermented beverage. An acute intervention study, cross-over design, was performed, with 15 healthy volunteers who consumed 500ml of either water, unfermented or fermented rooibos teas. Plasma antioxidant capacity increased significantly with both teas, reaching a peak at 1h post-consumption (+6.6%, p

In a randomized cross-over study, 15 healthy volunteers consumed 500 mL of green tea (GTFT) with different solid contents (1.4, 1.6, 1.8 and 2.0 g/L) to induce a dose-response effect on plasma antioxidant capacity. Ingestion of GTFT 2.0 g/L significantly increased plasma reducing power (ferric reducing antioxidant power, FRAP) at 1 h (+2.9%; p