Pectin structure and particle size modify carotenoid bioaccessibility and uptake by Caco-2 cells in citrus juices vs. concentrates.

Citrus pectin is known to influence carotenoid bioaccessibility and absorption in humans, but limited attention has been given to the influence of pectin structure related to the particle size from differentially processed citrus food matrices. In this context, this study aims to investigate the nutritional health benefits of an innovative Citrus clementina concentrate, which is a new citrus-based food made by cross-flow microfiltration. This concentrated citrus-based food was selectively enriched 8-fold in ß-cryptoxanthin (43-55 µg g-1) and ß-carotene (6-9 µg g-1) as well as 6-fold in pectin (376-462 mg per 100 g). The bioaccessibility of pro-vitamin A carotenoids from commercial and fresh clementina juices versus their concentrates was assessed, including the intestinal carotenoid uptake by Caco-2 cells. Differences in particles size and pectin status resulted in a 7-fold increase in the bioaccessibility of carotenoids in industrial products versus fresh products while limiting their cellular uptake in correlation with larger micelle sizes (10.6 nm and 6.82 nm for industrial and fresh concentrates, respectively). Overall, the highest carotenoid bioaccessibility from industrial concentrate was sufficient to offset the lower carotenoid intestinal uptake related to micelle size. This study highlights that the structure of pectins, more specifically their degree of methoxylation, favors carotenoid bioaccessibility but impairs the intestinal absorption of carotenoids from citrus concentrates.

Hepatic metabolic effects of Curcuma longa extract supplement in high-fructose and saturated fat fed rats.

The metabolic effects of an oral supplementation with a Curcuma longa extract, at a dose nutritionally relevant with common human use, on hepatic metabolism in rats fed a high fructose and saturated fatty acid (HFS) diet was evaluated. High-resolution magic-angle spinning NMR and GC/MS in combination with multivariate analysis have been employed to characterize the NMR metabolite profiles and fatty acid composition of liver tissue respectively. The results showed a clear discrimination between HFS groups and controls involving metabolites such as glucose, glycogen, amino acids, acetate, choline, lysophosphatidylcholine, phosphatidylethanolamine, and ß-hydroxybutyrate as well as an increase of MUFAs and a decrease of n-6 and n-3 PUFAs. Although the administration of CL did not counteract deleterious effects of the HFS diet, some metabolites, namely some n-6 PUFA and n-3 PUFA, and betaine were found to increase significantly in liver samples from rats having received extract of curcuma compared to those fed the HFS diet alone. This result suggests that curcuminoids may affect the transmethylation pathway and/or osmotic regulation. CL extract supplementation in rats appears to increase some of the natural defences preventing the development of fatty liver by acting on the choline metabolism to increase fat export from the liver.

Metabolomic and Lipidomic Analysis of Serum Samples following Curcuma longa Extract Supplementation in High-Fructose and Saturated Fat Fed Rats.

We explored, using nuclear magnetic resonance (NMR) metabolomics and fatty acids profiling, the effects of a common nutritional complement, Curcuma longa, at a nutritionally relevant dose with human use, administered in conjunction with an unbalanced diet. Indeed, traditional food supplements have been long used to counter metabolic impairments induced by unbalanced diets. Here, rats were fed either a standard diet, a high level of fructose and saturated fatty acid (HFS) diet, a diet common to western countries and that certainly contributes to the epidemic of insulin resistance (IR) syndrome, or a HFS diet with a Curcuma longa extract (1% of curcuminoids in the extract) for ten weeks. Orthogonal projections to latent structures discriminant analysis (OPLS-DA) on the serum NMR profiles and fatty acid composition (determined by GC/MS) showed a clear discrimination between HFS groups and controls. This discrimination involved metabolites such as glucose, amino acids, pyruvate, creatine, phosphocholine/glycerophosphocholine, ketone bodies and glycoproteins as well as an increase of monounsaturated fatty acids (MUFAs) and a decrease of n-6 and n-3 polyunsaturated fatty acids (PUFAs). Although the administration of Curcuma longa did not prevent the observed increase of glucose, triglycerides, cholesterol and insulin levels, discriminating metabolites were observed between groups fed HFS alone or with addition of a Curcuma longa extract, namely some MUFA and n-3 PUFA, glycoproteins, glutamine, and methanol, suggesting that curcuminoids may act respectively on the fatty acid metabolism, the hexosamine biosynthesis pathway and alcohol oxidation. Curcuma longa extract supplementation appears to be beneficial in these metabolic pathways in rats. This metabolomic approach highlights important serum metabolites that could help in understanding further the metabolic mechanisms leading to IR.

Growth and carcass attributes of growing Creole kids according to experimental infection level and type of diet.

In the tropics one of the major constraints to goat production is infection by gastrointestinal nematodes (GIN). One promising alternative to chemotherapy is the improvement of host nutrition. The aim of this study was to assess the effects of infection and supplementation on packed cell volume (PCV), average daily gain (ADG) and carcass quality in growing Creole kids. Sixty male goats were reared indoors following a 2 × 3 factorial design: two experimental infection levels, (infected (I) and non-infected (NI)) and three diets D (G, kids were fed exclusively with tropical forages; B, kids were supplemented with dried and crushed banana and C, kids were supplemented with commercial pellets). Faecal egg counts did not vary among I groups (on average 2,200 ω/g). The PCV and ADG were improved (P < 0.001) for NI vs. I animals. There was a D effect (P < 0.001) and no I × D interaction was observed. There was no significant effect of GIN on the main carcass data, except the weights of liver, white offal and abdominal fat, which increased slightly in I compared with NI goats (P < 0.05). All carcass data increased significantly with the addition of supplement in the diet (P < 0.001), except for carcass-cut proportions. Meat physical parameters were degraded when I kids received low N diets (B or G) with higher lightness and water loss than in the C groups. Given that GIN affect the animal's N metabolism it is recommended to avoid the use of unbalanced diet such as those banana-based. Further research is necessary to assess the nutrition × parasitism interactions on physiological features and carcass quality of Creole goats.

Neuronal conduction of excitation without action potentials based on ceramide production.

BACKGROUND: Action potentials are the classic mechanism by which neurons convey a state of excitation throughout their length, leading, after synaptic transmission, to the activation of other neurons and consequently to network functioning. Using an in vitro integrated model, we found previously that peripheral networks in the autonomic nervous system can organise an unconventional regulatory reflex of the digestive tract motility without action potentials. METHODOLOGY/PRINCIPAL FINDINGS: In this report, we used combined neuropharmacological and biochemical approaches to elucidate some steps of the mechanism that conveys excitation along the nerves fibres without action potentials. This mechanism requires the production of ceramide in membrane lipid rafts, which triggers in the cytoplasm an increase in intracellular calcium concentration, followed by activation of a neuronal nitric oxide synthase leading to local production of nitric oxide, and then to guanosine cyclic monophosphate. This sequence of second messengers is activated in cascade from rafts to rafts to ensure conduction of the excitation along the nerve fibres. CONCLUSIONS/SIGNIFICANCE: Our results indicate that second messengers are involved in neuronal conduction of excitation without action potentials. This mechanism represents the first evidence-to our knowledge-that excitation is carried along nerves independently of electrical signals. This unexpected ceramide-based conduction of excitation without action potentials along the autonomic nerve fibres opens up new prospects in our understanding of neuronal functioning.