Poster Topical Area: Aging and Chronic Disease
Poster Board Number: 93
In humans, unlike polyphenols, high-fat diets worsen endothelial function and increase markers of oxidative stress and inflammation. Polyphenols could exert beneficial effects on cardiovascular function especially in dogs fed with high-fat diets. The aim of this work was to assess the short- and medium-term effects of grape seed polyphenols (GSPP) on postprandial (pp) endothelial function, plasma lipids, and biomarkers of inflammation and oxidative stress in dogs.
Ten healthy adult Beagle dogs were used in two studies. First, dogs were given, at maintenance level, a standard diet (SD; 23% protein, 16% fat, 390 kcal ME/100g) for 5 wk. Every 8th day they received, in Latin-square, either no supplement, a GSPP supplement (1.53 mg/kg BW), a sunflower oil supplement (SFO; 10% of the SD, w/w), or both. Secondly, dogs were given the GSPP supplement for 3 weeks. On the 22nd day they were additionally given the SFO supplement. Flow-mediated dilatation (FMD), plasma triglycerides, total cholesterol, HDL-cholesterol, malondialdehyde, CRP, SAA, haptoglobin (Hp) concentrations were assayed right before, then 2 and 4h after the meal.
GSPP improved pp-FMD when dogs were given SD, but had no effect when they were also given SFO supplement. Postprandial Hp concentration was higher with SD+SFO compared to SD. It was not altered with SD+GSPP vs. SD. When dogs were given SD+SFO+GSPP, pp-Hp concentration was not different from SD nor SD+GSPP. At the end of the 3-wk GSPP supplementation, pp-FMD increase was higher and Hp concentration was lower than at the beginning. When SFO was additionally given on the 22nd day, pp-FMD change was no longer higher than that elicited by the SD alone. After 3 wk of GSPP supplementation, the SFO supplement did not elicit any change in Hp.
At the dose used, a single administration of GSPP improved endothelial function (FMD) but did not counteract the effects of dietary fat excess. Nevertheless GSPP abolished the haptoglobin increase elicited by the lipid supplement.For the medium term, the increase in FMD observed after the 3-wk GSPP supplementation confirm that administration of such polyphenols may improve endothelial function. This was concomitant to a decrease Hp concentration, marker of systemic inflammation, that notably consolidate the deleterious role of inflammatory state on endothelial function.
UPSP NP3 Nutrition, Physiopathology and Pharmacology, Oniris, France
Nantes, Pays de la Loire, France