References of "Nutrition"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailThe potency of commercial blackcurrant juices to induce relaxations in porcine coronary artery rings is not correlated to their antioxidant capacity but to their anthocyanin content
Tabart, Jessica ULiege; Auger, Cyril; Kevers, Claire ULiege et al

in Nutrition (2018), 51-52

Objective: Polyphenol-rich products such as fruit juices have been shown to have strong antioxidant capacities and to induce potent endothelium-dependent relaxations. We have evaluated whether the ... [more ▼]

Objective: Polyphenol-rich products such as fruit juices have been shown to have strong antioxidant capacities and to induce potent endothelium-dependent relaxations. We have evaluated whether the commercial blackcurrant juices induced endothelium-dependent relaxation of isolated coronary arteries can be related to their antioxidant capacity and/or phenolic content. Research Methods & Procedures: Six different commercial blackcurrant juices were selected. Their main phenolic compounds were measured by UPLC and antioxidant capacity was evaluated by spectrometric methods. Vascular reactivity studies with these juices were done using isolated porcine coronary arteries. Results: The six different commercial blackcurrant juices induced relaxations ranging from 21 to 100 % at the concentration of 0.5% v/v. The relaxation induced at 0.5 % v/v was not correlated to their antioxidant capacity measured by either ORAC or DPPH assays, and also not to the ascorbic acid, total polyphenols, total flavonols and total phenolic acid contents. In contrast, the amplitude of the relaxation was correlated to the total anthocyanins content and the individual anthocyanin concentration. Conclusions: Correlations between relaxation amplitude and total anthocyanin or individual anthocyanin contents are of interest for the development of functional blackcurrant beverages with the potential to promote vascular protection. [less ▲]

Detailed reference viewed: 16 (4 ULiège)
Peer Reviewed
See detailEffects of glucagon in the control of endogenous glucose production in man.
Surmely, J. F.; Schneiter, P.; Henry, S. et al

in Nutrition (1999), 15(4), 267-73

Endogenous glucose production has been shown to increase during administration of glucagon + fructose, but not during administration of fructose alone. To determine the mechanisms by which glucagon exerts ... [more ▼]

Endogenous glucose production has been shown to increase during administration of glucagon + fructose, but not during administration of fructose alone. To determine the mechanisms by which glucagon exerts this action, endogenous glucose production (EGP) and gluconeogenesis from fructose (GNF) were measured in eight healthy subjects infused 1) with graded doses of glucagon (2 and 4 ng.kg-1.min-1 for 3 h each) during constant infusion of 13C-fructose (3 mg.kg-1.min-1), and 2) with graded doses of 13C-fructose (3 and 6 mg.kg-1.min-1) during constant glucagon infusion (2 ng.kg-1.min-1). GNF was estimated from 13C-glucose synthesis. In both protocols, infusion of 3 mg.kg-1.min-1 fructose + 2 ng.kg-1.min-1 glucagon increased EGP by 5-8% (P < 0.05), while GNF represented 43-49% of EGP. Thereafter, increasing the glucagon infusion rate further increased EGP to 118 +/- 3% of basal values (P < 0.01) without altering the proportion due to GNF. In contrast, increasing the fructose infusion rate at constant glucagonemia increased EGP similarly (by 19 +/- 4%, P < 0.05) but enhanced the contribution of GNF to 76 +/- 2% (P < 0.001). Graded infusion of glucagon or fructose alone failed to stimulate EGP. The present findings indicate that hyperglucagonemia stimulates endogenous glucose production during fructose infusion. This effect is not secondary to a stimulation of gluconeogenesis, but to a channelling of glucose-6-phosphate towards systemic release. [less ▲]

Detailed reference viewed: 5 (1 ULiège)