Pro-atherogenic postprandial profile: Meal-induced changes of lipoprotein sub-fractions and inflammation markers in obese boys.

BACKGROUND AND AIMS: Obesity is a pro-atherogenic condition and postprandial lipoprotein profile and circulating cytokines changes may contribute to promote the process. The aim of this study is to investigate postprandial metabolic response, lipoprotein oxidation and circulating cytokine levels, after the ingestion of two different meals with different fat/carbohydrate ratio. METHODS AND RESULTS: Ten prepubertal obese boys consumed two meals with the same energy and protein content but with a different carbohydrate to fat ratio: 1) moderate fat (MF): 61\% carbohydrate, 27\% fat; 2) high fat (HF): 37\% carbohydrate, 52\% fat. The AUC of glucose and insulin were significantly (p\ua0\ua00.3, P\ua0<\ua00.05) was observed between the densest LDL particles and the ox-LDL plasma levels. A reduction of IL-6 was found at 120\ua0min after the MF [-23.3(5.5) vs -8.4(3.8)\% from baseline, P\ua0<\ua00.05)] compared with the HF meal. CONCLUSION: A simple change of 4825\% of energy load from fat to carbohydrate in a meal significantly improves postprandial pro-atherogenic factors in obese boys

A targeted metabolomics method for the rapid quantification of multiple classes of phenolics in the fruits of Rosaceae

In recent years, the interest in phenolic compounds has been increasing due to compelling evidences of their beneficial health properties and to their impact on food quality. The complexity and remarkable diversity of phenolics has challenged the analytical performances of separation and detection methods in terms of resolving power, selectivity and sensitivity for the identification and quantification of these compounds in different matrices. Targeted metabolomics is a strategy based on the use of predefined metabolite‐specific signals, such as MRM transitions, that can be used to accurately determine the concentrations of a wide range of known metabolites. We developed a rapid and versatile UPLC‐MS/MS based method for the quantification of >150 phenolics, such as benzoates, phenylpropanoids, coumarins, stilbenes, dihydrochalcones and flavonoids in fruits. Compounds commonly occurring in plants were included in the method together with metabolites specific of a single species or family. Reverse‐phase chromatography was optimised to achieve separation of the compounds over 15 min, reducing possible ion suppression effects and resolving many isomeric compounds. The optimal fragmentation conditions for each analyte were studied and MRM transitions were selected for accurate quantification. The effectiveness of the method was validated by studying the limits of detection and quantification, the linearity ranges of the instrumental response and the repeatability of the analysis. The method was successfully applied and validated for the analysis of apples, cherries, raspberries, strawberries, as well as grape, wine and green tea, and was shown to represent a valuable tool for the quantitative evaluation of the chemical phenotype, measuring the presence, amount and natural variance in phenolics composition of these fruits

Agrimoniin the most important ellagitannin in human diet: elucidation of its identity in strawberry fruits and the influence of fruit ripening on its concentration

Of the most commonly consumed berries, strawberries (Fragaria ananassa Duch.) are the most popular choice with consumers, being eaten both fresh and frozen, as well as in different processed products. Although the composition of strawberry fruit has been extensively studied, especially for the most abundant phenolic compounds, agrimoniin has been only recently univocally identified as one of the most abundant phenolic compounds in the fruit (Vrhovsek et al. 2012). In this study agrimoniin was isolated in the fruit of Fragaria vesca and its structure fully characterized, reporting for the first time the full NMR assignments for this dimeric ellagitannin. Agrimoniin is a known bioactive compound, which has been used for treatment of diarrhea and haemorrhaging and reported to have antitumor properties. Its presence as the main ellagitannin in both F. vesca and Fragaria ananassa D. fruit is therefore noticeable. The establishment of a new HPLC protocol for the separation of the strawberry ellagitannins, and the isolation and characterisation of other ellagic acid derivatives, allowed us to produce an accurate quantification of the main ellagitannins and ellagic acid conjugates in 6 different varieties of strawberry and in 2 woodland strawberry at four different ripening stages from the green stage up to overripe fruit. Of fruit containing ellagitannins, strawberries are the most widely consumed, and agrimoniin is suggested to be one of the most widely present ellagitannins in the human diet. Agrimoniin, together with the other strawberry ellagitannins and ellagic acid derivatives characterised in this study, deserve further attention since they are expected to play an important, yet still largely unexplored, role in the beneficial health effects associated with the consumption of strawberries by humans

From targeted analysis to untargeted metabolomics and its application in food and nutritional studies

Metabolomics is applied to a variety of biological fields from medical science to agriculture. Most of human beneficial properties of plants, be they foods, medical resources, or industrial raw materials, are ascribed to plant metabolites. One of the most important class of compounds are the polyphenols, due to compelling evidences of their beneficial health properties and to their impact on food quality. The complexity and remarkable diversity of polyphenols has challenged the analytical performances of the separation and detection methods in terms of resolving power, selectivity and sensitivity required for the identification and quantification of these compounds in different matrices. Targeted metabolomics is a strategy based on the use of predefined metabolite-specific signals, such as MRM transitions, that can be used to accurately and selectively determine the concentrations of a wide range of known metabolites. A targeted metabolomics method using UPLC/MS/MS system has been developed for the quantification >150 polyphenols and for the quantification of some polyphenols catabolites associated with the consumption of fruits. The validated method was found to be particularly flexible, since it can be easily expanded and adapted to the needs of different experiments. It was successfully applied to the analysis of various fruits and wine, as well as in nutritional studies, providing a valuable tool for the metabolite profiling of both the native compounds present in food and some nutritionally important bioactive catabolites in biofluids and organs. For a mechanistic understanding of the action of polyphenols in living organisms it is fundamental in nutritional studies to include also untargeted metabolomics, a powerful tool to study processes in organisms and to detect new biologically important biomarkers. In our study, a un-targeted high resolution mass spectrometry-based investigation was chosen to monitor the metabolic effects induced by administration of different dietary polyphenols, at a physiologically relevant dose, in adult male rats

Trgeted metabolomics methods for the separation and quantification of multiple classes of phenolics: application in food and nutritional studies

Compelling evidence of the health benefits of phenolic compounds and their impact on food quality have stimulated the development of analytical methods for the separation and quantification of these compounds in different matrices in recent years. The complexity and remarkable diversity of phenolics has challenged the analytical performances of separation and detection methods in terms of resolving power, selectivity and sensitivity for the identification and quantification of these compounds in different matrices. Targeted metabolomics is a strategy based on the use of predefined metabolite-specific signals, such as MRM transitions, that can be used to accurately determine the concentrations of a wide range of known metabolites. A targeted metabolomics method [1] has been developed for the quantification >150 phenolics, such as benzoates, phenylpropanoids, coumarins, stilbenes, dihydrochalcones, and flavonoids, using an UPLC/MS/MS system. Reverse-phase chromatography was optimised to achieve separation of the compounds over 15 min, reducing possible ion suppression effects and resolving many isomeric compounds and MRM transitions were selected for accurate quantification. Recently a new targeted metabolomics method [2] was developed for the quantification of 23 metabolites/catabolites related to the consumption of polyphenols and associated to the microbial digestion made by the gut microflora. The present new method was developed the analysis of complex matrix with SPE purification before the UPLC separation. Then it was validated and applied for human/animal biofluids or tissues. The validated methods were applied to the analysis of fruits and wine polyphenols as well as in nutritional studies providing a valuable tool for food quality evaluation and nutritional relevant bioactive compounds profiling. The short duration of the analysis and the straightforward sample preparation make the methodology suitable for high-throughput screening studies for analysis of food as well as its application in nutritional studies to biofluid

Overall dietary polyphenol intake in a bowl of strawberries: the influence of Fragaria spp. in nutritional studies

Strawberry (Fragaria × ananassa Duch.) is an important source of polyphenols in the human diet, and is considered a functional food. However, at the moment, it is not fully understood which compounds are involved. The aim was to present a comprehensive picture of the amount of polyphenols present in strawberry. A total of 56 individual compounds were identified and quantified with a triple-quadrupole mass spectrometer, their concentration ranging from 1 g/100 g to 40 mg/100 g of fresh fruit. Furthermore, spectrophotometric assay for estimation of high-molecular mass proanthocyanidins was applied. Several compounds were identified/quantified for the first tim

The Role of Visual-Haptic Discrepancy in Virtual Reality Environments

Visual-haptic interactions are of utmost importance for VR surgical simulators. We investigate the role of spatial visual-haptic discrepancy by manipulating the presentation order of visual and force feedback. Participants were asked to indicate the nearer wall between a visual and an pliable haptic virtual surface. We factorially manipulated the discrepancy levels (± 5, 15, 25 mm) and the stiffness values of the pliable haptic wall, 83 (human fat) and 331 N/m (human skin). Psychophysical curves over depth penetration and latency time inside the wall were estimated. Results showed that haptic and visual walls were indistinguishable among the discrepancy range of 10.57±23.12 mm for 83N/m and -3.07±9.11 mm for 331 N/m. The trend of psychophysical curves show as, in presence of discrepancies or errors between an haptic and a visual surface, the overall perception is influenced by the stiffness of the haptic surface, in according with a weighted summation model, showing a direct relation between the stiffness factor and the weight of the haptic component in the model. © 2012 IEEE