Over the past 2 decades there has been increasing evidence supporting an important contribution from food-derived advanced glycation end products (AGEs) to the body pool of AGEs and therefore increased oxidative stress and inflammation, processes that play a major role in the causation of chronic diseases. A 3-d symposium (1st Latin American Symposium of AGEs) to discuss this subject took place in Guanajuato, Mexico, on 1-3 October 2014 with the participation of researchers from several countries. This review is a summary of the different presentations and subjects discussed, and it is divided into 4 sections. The first section deals with current general knowledge about AGEs. The second section dwells on mechanisms of action of AGEs, with special emphasis on the receptor for advanced glycation end products and the potential role of AGEs in neurodegenerative diseases. The third section discusses different approaches to decrease the AGE burden. The last section discusses current methodologic problems with measurement of AGEs in different samples. The subject under discussion is complex and extensive and cannot be completely covered in a short review. Therefore, some areas of interest have been left out because of space. However, we hope this review illustrates currently known facts about dietary AGEs as well as pointing out areas that require further research.

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The RNA polymerase II (Pol II) core promoter is the strategic site of convergence of the signals that lead to transcription initiation 1 - 5 , but the downstream core promoter in humans has been difficult to decipher 1 - 3 . Here, we analyze the human Pol II core promoter and use machine learning to generate predictive models for the downstream core promoter region (DPR) and the TATA box. We developed a method termed HARPE (high-throughput analysis of randomized promoter elements) to create hundreds of thousands of DPR (or TATA box) variants that are each of known transcriptional strength. We then analyzed the HARPE data by support vector regression (SVR) to provide comprehensive models for the sequence motifs, and found that the SVR-based approach is more effective than a consensus-based method for predicting transcriptional activity. These studies revealed that the DPR is a functionally important core promoter element that is widely used in human promoters. Importantly, there appears to be a duality between the DPR and TATA box, as many promoters contain one or the other element. More broadly, these findings show that functional DNA motifs can be identified by machine learning analysis of a comprehensive set of sequence variants.

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Winemaking industry produces large amounts of by-products (grape pomace or marc) every year, making necessary a sustainable management of such waste. Among red wines, Tannat variety possesses a unique polyphenolic profile. Consequently, the study of the bioactive properties of its by-product and the extraction optimization of its bioactive compounds is of great interest to state its health promoting potential. In this study, different extraction processes were tested: maceration with ethanol (95 %), ultrasound assisted ethanolic extraction optimization with surface methodology, ultrasound assisted aqueous extraction and hydro-alcoholic-acid extraction (EHAA). Using this last extraction procedure higher polyphenolic content (11.459±1.048 g GAE/100g of dry extract), monomeric anthocyanins (2.030±0.085 g Cyd/100g of dry extract), antioxidant capacity (0.474±0.036 mg/mL for ABTS and 0.715±0.063 µmol TE/mg of dry extract for ORAC-FL), -glucosidase (IC50 888.5±79.3 µg/mL) and pancreatic lipase inhibition capacity (IC50 2431.0±79.9 µg/mL) was found on Tannat grape skin. Considering as a whole, these results may imply a great antidiabetic and antiobesity potential. Moreover, EHAA showed to have anti-inflammatory capacity (IC50 587 µg/mL) on RAW 264.7 cells. In summary, EHAA possesses great potential as a functional ingredient for prevention and/or treatment of chronic diseases.

Diabetes pathogenesis encompasses oxidative stress, inflammation, insulin malfunctioning and partial or total insulin secretion impairment, which leads to a constant hyperglycemia. Polyphenols are known to possess bioactive properties, being Tannat grape skin a natural and sustainable source of these compounds. The present study aimed to find out the bioaccessibility of health-promoting molecules composing a multifunctional extract from Tannat grape skin obtained under hydro-alcoholic-acid conditions. The identification of phenolic compounds in the samples was performed by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, the samples were in vitro digested mimicking the human oral gastrointestinal conditions and the bioactivity of the digest (antioxidant, anti-inflammatory and modulation of glucose metabolism) was assessed. Effect on glucose metabolism was estimated by measuring carbohydrases activity and the functionality of glucose transporters of small intestine cells in presence and absence of the digested extract. Flavonoids, phenolic acids and phenolic alcohols were the major phenol compounds detected in the extract. The bioaccessible compounds protected the intestinal cells and macrophages against the induced formation of reactive oxygen species (ROS) and nitric oxide (NO). In addition, glucose transporters were inhibited by the digested extract. In conclusion, the bioaccessible compounds of the extract, including phenols, modulated key biochemical events involved in the pathogenesis of diabetes such as oxidative stress, inflammation and glucose absorption. The extract was effective under prevention with co-administration conditions supporting its potential for either reducing the risk or treating this disease.

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Whey proteins are known for their high nutritional value and bioactivity, notably great potential is found on α-lactalbumin. The objective of this study was to evaluate antioxidant, antiglycant and ACE (angiotensin converting enzyme)-inhibitory activity of α-lactalbumin peptides obtained from enzymatic hydrolysis with Alcalase through different hydrolysis conditions. The optimization of enzymatic hydrolysis was studied by response surface methodology variating enzyme:substrate ratio (0.0050%, 0.0525% and 0.1000% w/w) and time (0, 30 and 60 minutes) measuring antioxidant activity by ABTS and ORAC-FL (response variables), founding an augment of this activity with time. Characterization of seven samples showed increasing hydrolysis with time. Hydrolysate obtained with 0.1000% w/w and 60 minutes demonstrated higher antioxidant activity related to greater hydrolysis. This hydrolysate did not show antiglycant activity but promoted advanced glycation end products formation with methylglyoxal and glucose. In contrast, this sample showed 30% of ACE inhibition when compared to Captopril, having great potential by enhancing hydrolysis.