Soluble fiber-enriched diets improve inflammation and oxidative stress biomarkers in Zucker fatty rats.

In this study we evaluated the effect of the administration of different soluble fiber enriched-diets on inflammatory and redox state of Zucker fatty rats. Four groups of ten 8 week-old female Zucker fatty rats were used. The four groups were respectively fed the following diets until the 15th week of life: standard diet (obese control), 10% high methoxylated apple pectin (HMAP)-, 5% soluble cocoa fiber (SCF)-, and 10% ß-glucan-enriched diets. A group of Zucker lean rats fed the standard diet was also used as control for normal values of this rat strain. The plasma levels of tumoral necrosis factor-α (TNF-α), adiponectin, and malondialdehyde (MDA) were measured at the end of treatment. The reduced glutathione liver levels were also obtained at that moment. TNF-α plasma levels decreased somewhat in Zucker fatty rats fed the different fibers, and MDA plasma levels significantly decreased in these animals. Nevertheless, adiponectin plasma levels increased in the Zucker fatty rats fed the SCF enriched diet, but did not change in the HMAP and the ß-glucan group. The Zucker fatty rats fed the different fiber showed a trend towards increased the reduced glutathione liver levels, but significant differences with obese control rats were only obtained in the ß-glucan group. The results obtained in this study suggest that the intake of the different soluble fiber-enriched diets that we have evaluated could prevent and/or attenuate the inflammatory and/or the prooxidative state of the metabolic syndrome.

Ellagic acid derivatives, ellagitannins, proanthocyanidins and other phenolics, vitamin C and antioxidant capacity of two powder products from camu-camu fruit (Myrciaria dubia).

The aims of this study were the evaluation of polyphenols and vitamin C content, and antioxidant capacity of dehydrated pulp powder and the dried flour obtained from the skin and seeds residue remaining after pulp preparation from camu-camu (Myrciaria dudia). Fifty-three different phenolics were characterised by HPLC-DAD-ESI-MS-MS and UPLC-HR-QTOF-MS-MS. The phenolic content of camu-camu flour was higher than that of the pulp powder (4007.95 mg/100 g vs. 48.54 mg/100 g). In both products the flavonol myricetin and conjugates, ellagic acid and conjugates and ellagitannins were detected. Cyanidin 3-glucoside, and quercetin and its glycosides were only found in the pulp powder, while proanthocyanidins were only present in the flour (3.5 g/100 g, mean degree of polymerisation 3). The vitamin C content was lower in pulp powder (3.5%) than in the flour (9.1%). The radical-scavenging capacity of both powders was determined by the DPPH, ABTS and ORAC assays, and was higher for camu-camu flour as could be expected for its higher phenolics and vitamin C content. Comparative analyses with fresh camu-camu berries indicate that some transformations occur during processing. Analysis of fresh berries showed that ellagic acid derivatives and ellagitannins were mainly present in the seeds, while proanthocyanidins were present both in the seeds and skin.

Effect of a soluble cocoa fiber-enriched diet in Zucker fatty rats.

The effects of a soluble cocoa fiber (SCF) were studied in Zucker fatty rats. Two groups of Zucker fatty rats were fed the following diets: standard diet and 5% SCF-enriched diet. A group of Zucker lean rats fed the standard diet was used for results comparison with obese Zucker animals. Solid and liquid intakes, body weight, plasma glucose, lipid profile, and systolic (SBP) and diastolic (DBP) blood pressure were recorded weekly. At the end of the experimental period insulin was determined, and fat apparent digestibility (FAD) and insulin resistance were calculated. The Zucker fatty rats fed 5% SCF-enriched diet showed less weight gain and food intake than those fed the standard diet. The group fed the fiber-enriched diet showed lower values of the total cholesterol/high-density lipoprotein cholesterol ratio and triglyceride levels than the standard group. FAD was also lower in the fiber group. Both SBP and DBP were decreased. In addition, SCF reduced plasma glucose and insulin, and as a consequence the insulin resistance was also decreased. Our data demonstrate that SCF resulted in an improvement of the studied risk factors associated with cardiometabolic disorders.

Antihypertensive effect of a polyphenol-rich cocoa powder industrially processed to preserve the original flavonoids of the cocoa beans.

A natural flavonoid-enriched cocoa powder, commercially named CocoanOX and developed via a patented industrial process, was characterized and tested for a possible antihypertensive effect. The bioavailability of this polyphenol-rich cocoa powder developed at pilot scale was previously demonstrated in humans. The present results showed that this product was very rich in total procyanidins (128.9 mg/g), especially monomers, dimers, and trimers (54.1 mg/g), and mainly (-)-epicatechin (19.36 mg/g). The effect of a single oral administration of CocoanOX in spontaneously hypertensive rats (SHR) was evaluated at different doses (50, 100, 300, and 600 mg/kg). This product produced a clear antihypertensive effect in these animals, but these doses did not modify the arterial blood pressure in the normotensive Wistar-Kyoto rats. Paradoxically, the maximum effect in the systolic blood pressure (SBP) of SHR was caused by 300 mg/kg of CocoanOX. This dose brought about a decrease in this variable very similar to that caused by 50 mg/kg Captopril. It was also surprising that the maximum effect in the diastolic blood pressure (DBP) was caused by 100 mg/kg CocoanOX. The initial values of DBP and SBP were recovered in SHR, respectively, 24 and 48 h postadministration of the different doses of CocoanOX or Captopril. These results suggest that CocoanOX could be used as a functional ingredient with antihypertensive effect, although it would be also necessary to carry out bioavailability and clinical studies to demonstrate its long-term antihypertensive efficiency in humans.

Hypolipidemic effect in cholesterol-fed rats of a soluble fiber-rich product obtained from cocoa husks.

A new soluble cocoa fiber product (SCFP), obtained after enzymatic treatment of cocoa husks, was characterized and its potential health effects studied in an animal model of dietary-induced hypercholesterolemia. The SCFP was rich in soluble dietary fiber (DF) and antioxidant polyphenols. Consumption of a cholesterol-rich diet containing the SCFP as a source of DF resulted in lower food intake and body weight gain in comparison with control groups consuming cholesterol-free or cholesterol-rich diets with cellulose as DF. The cholesterol-rich diet caused remarkable hypercholesterolemia. However, the SCFP diminished the negative impact of the cholesterol-rich diet, buffering the decrease of high density lipoprotein-cholesterol, and the increase of total and low density lipoprotein-cholesterol levels, and lipid peroxidation (malondialdehyde levels) induced by the fatty diet. The SCFP also decreased triglyceride levels to values lower than those in the group fed the cholesterol-free diet. These results put forward the potential application of the SCFP as a dietary supplement or functional food ingredient.