Prebióticos y nucleótidos en alimentación infantil: revisión de la evidencia

Introduction: Most of the initiation and maintenance pediatric formulas commercialized in Spain contain prebiotics and/or nucleotides aiming at achieving beneficial effects on prevention of different pathologies and immune protection, similar to human breast milk. However, according to the current legislation, its inclusion is optional since sufficient scientific evidences supporting its mandatory inclusion is lacking. Objective: To systematically review the scientific evidence from randomized clinical studies with a control group allowing determining the beneficial role for infant health derived from the inclusion of prebiotics and/or nucleotides in pediatric formulas. Methodology: We looked for and selected both original papers and reviews in Spanish and English language of placebo controlled randomized clinical studies published in the databases MEDLINE/PubMed, Scielo, Science Direct, and Scopus, until October of 2011. Results: We found 43 randomized clinical trials meeting the inclusion criteria. Conclusions: More long-term randomized studies with higher number of patients, and standardized supplemental amounts and experimental conditions are needed to establish healthy statements with stronger scientific support regarding the addition of a mixture of prebiotics (GOS/FOS) and/or nucleotides in pediatric formulas. The current trend to include them in pediatric formulas may be justified based on the currently available evidence, as well as their safety and their presence in human breast milk

Effect of milk based fruit beverage enriched with plant sterols and/or galactooligosaccharides in a murine chronic colitis model

The potential anti-inflammatory effect of plant sterols (PS) enriched milk-based fruit beverages (PS, 1 g/100 mL) (MfB) with/without galactooligosaccharides (GOS, 2 g/100 mL) (MfB-G) in an experimental mice model of chronic ulcerative colitis was evaluated. Beverages were orally administered to mice every day by gavage to achieve PS and GOS doses of 35 and 90 mg/kg, respectively, and experimental colitis was induced by giving mice drinking water ad libitum containing 2% (w/v) dextran sulphate sodium (DSS) for 7 days, alternating with periods without DSS up to the end of the study (56 days). MfB beverage showed significant reduction of symptoms associated to ulcerative colitis and improved the colon shortening and mucosal colonic damage, but it was not able to reduce the increase of myeloperoxidase levels produced by DSS. MfB-G showed higher incidence of bloody feces and loss of stool consistency than MfB, as well as high levels of immune cells infiltration in colon tissue and myeloperoxidase. Therefore, PS-enriched milk-based fruit beverage could be an interesting healthy food to extend the remission periods of the diseases and the need to evaluate, in a pre-clinical model, the anti-inflammatory effect of the combination of bioactive compounds in the context of a whole food matrix

Evaluation of the bioaccessibility of antioxidant bioactive compounds and minerals of four genotypes of Brassicaceae microgreens

Microgreens constitute an emerging class of fresh, healthy foods due to their nutritional composition. In this study the content of minerals and antioxidant bioactive compounds, and for the first time bioaccessibility, were evaluated in broccoli (Brassica oleracea L. var. italica Plenck), green curly kale (Brassica oleracea var. sabellica L.), red mustard (Brassica juncea (L.) Czern.) and radish (Raphanus sativus L.) hydroponic microgreens. Macro- (K, Ca, Mg) and oligo-elements (Fe, Zn), ascorbic acid, total soluble polyphenols, total carotenoids, total anthocyanins, total isothiocyanates and total antioxidant capacity (Trolox Equivalent Antioxidant Capacity and Oxygen Radical Absorbance Capacity) were determined before and after the standardized simulated gastrointestinal digestion process. All microgreens provided relevant amounts of vitamin C (31-56 mg/100 g fresh weight) and total carotenoids (162-224 mg β-carotene/100 g dry weight). Mineral content was comparable to that normally found in hydroponic microgreens and the low potassium levels observed would allow their dietetic recommendation for patients with impaired kidney function. Both total soluble polyphenols and total isothiocyanates were the greatest contributors to the total antioxidant capacity after digestion (43-70% and 31-63% bioaccessibility, respectively) while macroelements showed an important bioaccessibility (34-90%). In general, radish and mustard presented the highest bioaccessibility of bioactive compounds and minerals. Overall, the four hydroponic Brassicaceae microgreens present a wide array of antioxidant bioactive compounds

Ethylcoprostanol modulates colorectal cancer cell proliferation and mitigates cytotoxicity of cholesterol metabolites in non-tumor colon cells

Sterols can be metabolized by gut microbiota. The cholesterol metabolites have been proposed as promoters of colorectal cancer (CRC), while the effect of plant sterol metabolites is unknown. This study aimed to evaluate the cytotoxicity of metabolites from cholesterol (coprostanol, cholestanol, coprostanone and cholestenone) and β-sitosterol (ethylcoprostanol) on human colon tumor (Caco-2) and nontumor (CCD-18Co) cells at physiological concentrations (9-300 μM) and exposure time (24 h). Ethylcoprostanol reduced the tumor cell proliferation (MTT), showing in flow cytometry assays induction of apoptosis via production of reactive oxygen species (ROS) and ceramide. Transcriptomic analysis (qPCR) showed activation of the intrinsic apoptosis pathway (BAX/BCL2 ratio and CASP9 increased), accompanied by downregulation of the p21 gene. Cholesterol metabolites, mainly the most hydrophobic, induced apoptosis and G0/G1 phase arrest in non-tumor cells through overproduction of ROS. Both the intrinsic and extrinsic (CASP8 increased) apoptosis pathways occurred. In turn, a reduction in the expression of the cyclin E1 gene confirmed the cell cycle arrest. In addition, ethylcoprostanol protected non-tumor cells from the most cytotoxic cholesterol metabolite (cholestenone). In conclusion, ethylcoprostanol is a promising candidate as a therapeutic adjuvant in CRC, while cholesterol metabolites could act as CRC promoters through their cytotoxicity

Current methodologies for phytosterol analysis in foods

Plant sterols (PS) (phytosterols and phytostanols) are bioactive compounds of all vegetable foods where can be found as free sterol alcohols and as conjugates. These latter forms have been less studied, although they may have potential beneficial effects, whereas some PS have several approved health claims, especially in lowering blood cholesterol levels. In this context, it is necessary to establish analytical methods for food authentication, assessing PS health benefits and unfolding future applications. Several extraction methodologies have been employed for the extraction of PS from food matrixes (usually solvent extraction and saponification) although solid-phase extraction, solid-phase microextraction or enzymes have also been applied. In addition, the determination of PS may also need a subsequent saponification, purification or enrichment step before their determination. Gas chromatography after derivatization has historically been the method of choice for analysis, although liquid chromatography simplifies the analysis. Furthermore, although various detectors have been employed in analysing PS, mass spectrometry can address many of the challenges observed in other methodologies. Therefore, it has been widely used in conjunction with other separation techniques due to its sensitivity and selectivity by the application of tandem mass spectrometry. This review provides an overall and critical picture of the current methodologies used for the analysis of PS in foods, particularly focused on the individual applications and limitations

Overview of in vitro digestion methods to evaluate bioaccessibility of lipophilic compounds in foods

In vitro digestion models for assessing the bioaccessibility of lipophilic compounds from foodstuffs can either be static or dynamic. Carotenoids are the most widely studied compounds, while there is hardly any information on sterols and fat-soluble vitamins available, nor on the use of dynamic methods. There is a large variability in the parameters of static methods, which makes data comparison difficult. To harmonize digestion conditions and compare bioaccessibility, INFOGEST model has been established. This review assesses the most relevant digestion methods (non-INFOGEST, INFOGEST and dynamic) applied to carotenoids, sterols, and fat-soluble vitamins in food matrices in the last ten years

In vitro colonic fermentation of a plant sterol-enriched beverage in a dynamic-colonic gastrointestinal digester

The impact of a plant sterol-enriched beverage on the sterol metabolism, organic acid production and microbiota composition was evaluated by means of a dynamic gastrointestinal and colonic fermentation model. After one week of fermentation, an absence of sterol metabolites was reported, in accordance with the lack of microbiota related to their metabolism. Although total organic acid content was lower in the ascending colon (AC) compared to the transversal (TC) and descending colon (DC) (28-57 mmol/L vs. 55-87 and 44-64 mmol/L, respectively), its increments, with respect to the initial value, were higher (2-fold vs. 1.6- and 1.5-fold). Increments of acetate, butyrate and propionate were observed in all colon vessels, whereas lactate production was only observed in the AC at the first hours of fermentation. Results showed a progressive increase in microbial species richness and evenness from the AC to the DC. Beverage fermentation also modulated certain members of the microbiota: Bifidobacterium (within 24 h) and Megasphaera genera were stimulated, and Mitsuokella was reduced in AC, while the growth of Klebsiella genus was promoted and Bacteroidetes phylum decreased in TC and DC. These results show that the beverage modulates the microbial community and activity, which could be physiologically relevant to the host

Effect of plant sterol and galactooligosaccharides enriched beverages on oxidative stress and longevity in Caenorhabditis elegans

This study evaluates the impact of two plant sterol (PS) enriched fruit beverages (0.6 g /100 ml), without (MfB) or with GOS (MfB-G) (1.2 g/100 ml) on the resistance against oxidative stress induced by non-conventional (cholesterol oxidation products (COPs)) and conventional (H2O2) oxidant compounds, as well as their impact on C. elegans longevity. Nematodes fed with both beverages (0.005-0.25%, v/v) showed similar improved oxidative stress resistance against COPs and H2O2. This effect was dependent on daf-16 transcription factor, although GOS showed an additional beneficial effect independent to daf-16. In addition, both beverages extended nematode lifespan, independently of the presence of GOS. Longevity assays using daf-16 and daf-2 mutant strains revealed that the observed effect was potentially linked to the insulin-IGF-1 pathway. These results provide new in vivo evidence for the potential use of PS enriched fruit beverages in the prevention of oxidative stress underlying many diseases.Ministerio de Economía y CompetitividadFondo Europeo de Desarrollo RegionalGeneralitat Valencian

Bioaccessibility of plant sterols in wholemeal rye bread using the INFOGEST protocol: Influence of oral phase an enzymes of lipid metabolism.

Bioaccessibility of plant sterols (PS) in an enriched wholemeal rye bread was evaluated, for the first time, using the INFOGEST protocol without gastric lipase (GL) and cholesterol esterase (CE), with GL or GL + CE. Moreover, human chewing and an in vitro oral phase (simulated salivary fluid and α-amylase) were evaluated for this purpose. The addition of GL decreased the bioaccessibility of total PS (from 23.8 to 18.5%), whereas the use of GL + CE does not significantly affect PS bioaccessibility. The in vitro oral phase resulted in an ineffective homogenization of the fresh vs partially dried and milled bread, reducing the bioaccessibility of total (from 20.2 to 12.8%) and individual PS. The INFOGEST digestion including the use of GL and CE, as well as an oral phase with human chewing, is proposed for the assessment of PS bioaccessibility in a solid matrix such as wholemeal rye bread since it more closely approximates the in vivo situation

Elderly gastrointestinal conditions increase sterol bioaccessibility in a plant sterol-enriched beverage: adaptation of the INFOGEST method

Elderly people suffer from a higher cardiovascular risk. Thus, the fortification of foods with plant sterols (PSs), which have a cholesterol-lowering function, could be of great interest for this target group. To date, no studies have analyzed how the gastrointestinal conditions of the elderly affect PS bioaccessibility. Therefore, this study evaluated the impact of the adaptation of the gastric phase alone and in combination with the intestinal phase on sterol bioaccessibility. For this purpose, the standardized INFOGEST 2.0 method previously adapted for sterol bioaccessibility evaluation in healthy adults was applied to PSenriched milk-based fruit beverages, examining changes in enzyme activity, incubation time, agitation and pH, based on elderly physiology. The results suggest that the specific gastrointestinal conditions of the elderly could increase absorption of PSs, since their bioaccessibility (%) in a PS-enriched milk-based fruit beverage was significantly increased compared with that in adults (14.95 ± 0.33 vs. 7.96 ± 0.26), also indicating that these conditions increase the bioaccessibility of the beverage's own cholesterol (61.25 ± 2.91 vs. 20.86 ± 2.79). These data support the recommendation of foods of this type for the elderly who can benefit from the increase in bioaccessibility of PSs to have an improved potential cholesterol lowering effect, thus decreasing their risk of cardiovascular disease. However, the performance of subsequent in vivo tests to confirm these results is necessary