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This study investigated the influence of photoperiod (day length) on the efficacy of grape seed proanthocyanidin extract (GSPE) in mitigating metabolic disorders in obese rats fed a cafeteria diet. Rats were exposed to standard (L12), long (L18), or short (L6) photoperiods and treated with GSPE or vehicle. In the standard photoperiod, GSPE reduced body weight gain (50.5%), total cholesterol (37%), and triglycerides (34.8%), while increasing the expression of hepatic metabolic genes. In the long photoperiod, GSPE tended to decrease body weight gain, increased testosterone levels (68.3%), decreased liver weight (12.4%), and decreased reverse serum amino acids. In the short photoperiod, GSPE reduced glycemia (~10%) and lowered triglyceride levels (38.5%), with effects modified by diet. The standard photoperiod showed the greatest efficacy against metabolic syndrome-associated diseases. The study showed how day length affects GSPE’s benefits and underscores considering biological rhythms in metabolic disease therapies.

Seasonal rhythms drive metabolic adaptations that influence body weight and adiposity. Adipose tissue is a key regulator of energy homeostasis in the organism, and its healthiness is needed to prevent the major consequences of overweight and obesity. In this context, supplementation with proanthocyanidins has been postulated as a potential strategy to prevent the alterations caused by obesity. Moreover, the effects of these (poly)phenols on metabolism are photoperiod dependent. In order to describe the impact of grape-seed proanthocyanidins extract (GSPE) on important markers of adipose tissue functionality under an obesogenic environment, we exposed Fischer 344 rats to three different photoperiods and fed them a cafeteria diet for five weeks. Afterwards, we supplemented them with 25 mg GSPE/kg/day for four weeks. Our results revealed that GSPE supplementation prevented excessive body weight gain under a long photoperiod, which could be explained by increased lipolysis in the adipose tissue. Moreover, cholesterol and non-esterified fatty acids (NEFAs) serum concentrations were restored by GSPE under standard photoperiod. GSPE consumption slightly helped combat the obesity-induced hypertrophy in adipocytes, and adiponectin mRNA levels were upregulated under all photoperiods. Overall, the administration of GSPE helped reduce the impact of obesity in the adipose tissue, depending on the photoperiod at which GSPE was consumed and on the type of adipose depots.

Energy homeostasis and metabolism in mammals are strongly influenced by seasonal changes. Variations in photoperiod patterns drive adaptations in body weight and adiposity, reflecting changes in the regulation of food intake and energy expenditure. Humans also show distinct patterns of energy balance depending on the season, being more susceptible to gaining weight during a specific time of the year. Changes in body weight are mainly reflected by the adipose tissue, which is a key metabolic tissue and is highly affected by circannual rhythms. Mostly, in summer-like (long-active) photoperiod, adipocytes adopt a rather anabolic profile, more predisposed to store energy, while food intake increases and energy expenditure is reduced. These metabolic adaptations involve molecular modifications, some of which have been studied during the last years and are summarized in this review. In addition, there is a bidirectional relation between obesity and the seasonal responses, with obesity disrupting some of the seasonal responses observed in healthy mammals, and altered seasonality being highly associated with increased risk of developing obesity. This suggests that changes in photoperiod produce important metabolic alterations in healthy organisms. Biological rhythms impact the regulation of metabolism to different extents, some of which are already known, but further research is needed to fully understand the relationship between energy balance and seasonality.

Tomatoes are widely consumed worldwide at any time of the year. However, depending on the variety, they have a characteristic season. We evaluated the consequences metabolic of consumption of Ekstasis tomatoes from different geographical origin and in different seasons in Fischer 344 rats. The hepatic gene expression of key enzymes in lipid metabolism was also evaluated. Animals were classified in three photoperiods (L6, L12, and L18) and in three treatments (vehicle: VH; local tomato: LT; and non-local tomato: nLT). We measured serum metabolic parameters and the gene expression of liver enzymes related to lipid metabolism (Acc1, Cpt1a, Had, Fas1, Srebp-1c, Fatp5, Cd36). LT consumption in season decreased cardiovascular risk 1 and coefficient atherogenic by 1.81 (p = 0.031) and in L6 decreased TAG and glucose (p = 0.046; p = 0.024). The L18-LT animals had decreased total cholesterol (p = 0.029) and gene expression of Srebp1-c (p = 0.022) but increased expression of Acc1 (p = 0.032). The treatments significantly affected the expression of Acc1 and Fas1 in the liver and the levels of serum TAG and glucose. A significant effect of photoperiod on serum concentration of glucose, insulin, HOMA index, and on the hepatic expression of Srep1-c, Fas1, and Acc1 was observed.

Obesity is an epidemic disease worldwide, characterized by excessive fat accumulation associated with several metabolic perturbations, such as metabolic syndrome, insulin resistance, hypertension, and dyslipidemia. To improve this situation, a specific combination of metabolic cofactors (MC) (betaine, N-acetylcysteine, L-carnitine, and nicotinamide riboside) was assessed as a promising treatment in a high-fat diet (HFD) mouse model. Obese animals were distributed into two groups, orally treated with the vehicle (obese + vehicle) or with the combination of metabolic cofactors (obese + MC) for 4 weeks. Body and adipose depots weights; insulin and glucose tolerance tests; indirect calorimetry; and thermography assays were performed at the end of the intervention. Histological analysis of epidydimal white adipose tissue (EWAT) and brown adipose tissue (BAT) was carried out, and the expression of key genes involved in both fat depots was characterized by qPCR. We demonstrated that MC supplementation conferred a moderate reduction of obesity and adiposity, an improvement in serum glucose and lipid metabolic parameters, an important improvement in lipid oxidation, and a decrease in adipocyte hypertrophy. Moreover, MC-treated animals presented increased adipose gene expression in EWAT related to lipolysis and fatty acid oxidation. Furthermore, MC supplementation reduced glucose intolerance and insulin resistance, with an increased expression of the glucose transporter Glut4; and decreased fat accumulation in BAT, raising non-shivering thermogenesis. This treatment based on a specific combination of metabolic cofactors mitigates important pathophysiological characteristics of obesity, representing a promising clinical approach to this metabolic disease.

The gut is a selective barrier that not only allows the translocation of nutrients from food, but also microbe-derived metabolites to the systemic circulation that flows through the liver. Microbiota dysbiosis occurs when energy imbalances appear due to an unhealthy diet and a sedentary lifestyle. Dysbiosis has a critical impact on increasing intestinal permeability and epithelial barrier deterioration, contributing to bacterial and antigen translocation to the liver, triggering non-alcoholic fatty liver disease (NAFLD) progression. In this study, the potential therapeutic/beneficial effects of a combination of metabolic cofactors (a multi-ingredient; MI) (betaine, N-acetylcysteine, L-carnitine, and nicotinamide riboside) against NAFLD were evaluated. In addition, we investigated the effects of this metabolic cofactors’ combination as a modulator of other players of the gut-liver axis during the disease, including gut barrier dysfunction and microbiota dysbiosis. Diet-induced NAFLD mice were distributed into two groups, treated with the vehicle (NAFLD group) or with a combination of metabolic cofactors (NAFLD-MI group), and small intestines were harvested from all animals for histological, molecular, and omics analysis. The MI treatment ameliorated gut morphological changes, decreased gut barrier permeability, and reduced gene expression of some proinflammatory cytokines. Moreover, epithelial cell proliferation and the number of goblet cells were increased after MI supplementation. In addition, supplementation with the MI combination promoted changes in the intestinal microbiota composition and diversity, as well as modulating short-chain fatty acids (SCFAs) concentrations in feces. Taken together, this specific combination of metabolic cofactors can reverse gut barrier disruption and microbiota dysbiosis contributing to the amelioration of NAFLD progression by modulating key players of the gut-liver axis.

Seasonality is gaining attention in the modulation of some physiological and metabolic functions in mammals. Furthermore, the consumption of natural compounds, such as GSPE, is steadily increasing. Consequently, in order to study the interaction of seasonal variations in day length over natural compounds’ molecular effects, we carried out an animal study using photo-sensitive rats which were chronically exposed for 9 weeks to three photoperiods (L6, L18, and L12) in order to mimic the day length of different seasons (winter/summer/and autumn-spring). In parallel, animals were also treated either with GSPE 25 (mg/kg) or vehicle (VH) for 4 weeks. Interestingly, a seasonal-dependent GSPE modulation on the hepatic glucose and lipid metabolism was observed. For example, some metabolic genes from the liver (SREBP-1c, Gk, Acacα) changed their expression due to seasonality. Furthermore, the metabolomic results also indicated a seasonal influence on the GSPE effects associated with glucose-6-phosphate, D-glucose, and D-ribose, among others. These differential effects, which were also reflected in some plasmatic parameters (i.e., glucose and triglycerides) and hormones (corticosterone and melatonin), were also associated with significant changes in the expression of several hepatic circadian clock genes (Bmal1, Cry1, and Nr1d1) and ER stress genes (Atf6, Grp78, and Chop). Our results point out the importance of circannual rhythms in regulating metabolic homeostasis and suggest that seasonal variations (long or short photoperiods) affect hepatic metabolism in rats. Furthermore, they suggest that procyanidin consumption could be useful for the modulation of the photoperiod-dependent changes on glucose and lipid metabolism, whose alterations could be related to metabolic diseases (e.g., diabetes, obesity, and cardiovascular disease). Furthermore, even though the GSPE effect is not restricted to a specific photoperiod, our results suggest a more significant effect in the L18 condition.

Consumption of grape seed proanthocyanidin extract (GSPE) has beneficial effects on the functionality of white adipose tissue (WAT). However, although WAT metabolism shows a clear diurnal rhythm, whether GSPE consumption could affect WAT rhythmicity in a time-dependent manner has not been studied. Ninety-six male Fischer rats were fed standard (STD, two groups) or cafeteria (CAF, four groups) diet for 9 weeks (n = 16 each group). From week 6 on, CAF diet animals were supplemented with vehicle or 25 mg GSPE/kg of body weight either at the beginning of the light/rest phase (ZT0) or at the beginning of the dark/active phase (ZT12). The two STD groups were also supplemented with vehicle at ZT0 or ZT12. In week 9, animals were sacrificed at 6 h intervals (n = 4) to analyze the diurnal rhythms of subcutaneous WAT metabolites by nuclear magnetic resonance spectrometry. A total of 45 metabolites were detected, 19 of which presented diurnal rhythms in the STD groups. Although most metabolites became arrhythmic under CAF diet, GSPE consumption at ZT12, but not at ZT0, restored the rhythmicity of 12 metabolites including compounds involved in alanine, aspartate, and glutamate metabolism. These results demonstrate that timed GSPE supplementation may restore, at least partially, the functional dynamics of WAT when it is consumed at the beginning of the active phase. This study opens an innovative strategy for time-dependent polyphenol treatment in obesity and metabolic diseases.

Variations in the light/dark cycle and obesogenic diets trigger physiological and behavioral disorders. Proanthocyanidins, in addition to their healthy properties, have recently demonstrated a modulating effect on biological rhythms. Therefore, the aim of this study was to evaluate the administration of a grape seed proanthocyanidin-rich extract (GSPE) to mitigate the disruption caused by a sudden photoperiod change in healthy and cafeteria (CAF)-diet obese rats. For this, 48 photoperiod-sensitive Fischer 344 rats were fed standard or CAF diets for 6 weeks under a standard (12 h light/day, L12) conditions. Then, rats were switched to a long (18 h light/day, L18) or short (6 h light/day, L6) photoperiod and administered vehicle or GSPE (25 mg/kg) for 1 week. Body weight (BW) and food intake (FI) were recorded weekly. Animal activity and serum hormone concentrations were studied before and after the photoperiod change. Hormone levels were measured both at 3 h (ZT3) and 15 h (ZT15) after the onset of light. Results showed the impact of the CAF diet and photoperiod on the BW, FI, activity, and hormonal status of the animals. GSPE administration resulted in an attenuation of the changes produced by the photoperiod disruption. Specifically, GSPE in L6 CAF-fed rats reduced serum corticosterone concentration, restoring its circadian rhythm, increased the T3-to-T4 ratio, and increased light phase activity, while under L18, it decreased BW and testosterone concentration and increased the animal activity. These results suggest that GSPE may contribute to the adaptation to the new photoperiods. However, further studies are needed to elucidate the metabolic pathways and processes involved in these events.

Major susceptibility to alterations in liver function (e.g., hepatic steatosis) in a prone environment due to circadian misalignments represents a common consequence of recent sociobiological behavior (i.e., food excess and sleep deprivation). Natural compounds and, more concisely, polyphenols have been shown as an interesting tool for fighting against metabolic syndrome and related consequences. Furthermore, mitochondria have been identified as an important target for mediation of the health effects of these compounds. Additionally, mitochondrial function and dynamics are strongly regulated in a circadian way. Thus, we wondered whether some of the beneficial effects of grape-seed procyanidin extract (GSPE) on metabolic syndrome could be mediated by a circadian modulation of mitochondrial homeostasis. For this purpose, rats were subjected to “standard”, “cafeteria” and “cafeteria diet + GSPE” treatments (n = 4/group) for 9 weeks (the last 4 weeks, GSPE/vehicle) of treatment, administering the extract/vehicle at diurnal or nocturnal times (ZT0 or ZT12). For circadian assessment, one hour after turning the light on (ZT1), animals were sacrificed every 6 h (ZT1, ZT7, ZT13 and ZT19). Interestingly, GSPE was able to restore the rhythm on clock hepatic genes (Bmal1, Per2, Cry1, Rorα), as this correction was more evident in nocturnal treatment. Additionally, during nocturnal treatment, an increase in hepatic fusion genes and a decrease in fission genes were observed. Regarding mitochondrial complex activity, there was a strong effect of cafeteria diet at nearly all ZTs, and GSPE was able to restore activity at discrete ZTs, mainly in the diurnal treatment (ZT0). Furthermore, a differential behavior was observed in tricarboxylic acid (TCA) metabolites between GSPE diurnal and nocturnal administration times. Therefore, GSPE may serve as a nutritional preventive strategy in the recovery of hepatic-related metabolic disease by modulating mitochondrial dynamics, which is concomitant to the restoration of the hepatic circadian machinery.

The use of a single family of dietary bioactive compounds has not been sufficient to manage highly regulated mechanisms such as body weight. Therefore, we aimed to evaluate the effect of a multifunctional ingredient (MIX) based on the co-administration of a low dose of conjugated linoleic acid with the protein hydrolysate from chicken feet, Hpp11, and a mixture of grape-seed proanthocyanidins and berry anthocyanins on body weight management in obese rats fed a cafeteria diet. The daily oral administration of the MIX for three weeks significantly reversed obesity and hyperleptinemia and increased energy expenditure and fat oxidation. In addition, animals administered the MIX exhibited greater hypothalamic activation of STAT3 in POMC-expressing neurons than non-supplemented animals. Our results strongly suggest that the co-administration of different bioactive compounds could be a promising strategy to complement the existing therapies against obesity and leptin resistance.

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) have emerged as the leading causes of chronic liver disease in the world. Obesity, insulin resistance, and dyslipidemia are multifactorial risk factors strongly associated with NAFLD/NASH. Here, a specific combination of metabolic cofactors (a multi-ingredient; MI) containing precursors of glutathione (GSH) and nicotinamide adenine dinucleotide (NAD+) (betaine, N-acetyl-cysteine, L-carnitine and nicotinamide riboside) was evaluated as effective treatment for the NAFLD/NASH pathophysiology. Six-week-old male mice were randomly divided into control diet animals and animals exposed to a high fat and high fructose/sucrose diet to induce NAFLD. After 16 weeks, diet-induced NAFLD mice were distributed into two groups, treated with the vehicle (HFHFr group) or with a combination of metabolic cofactors (MI group) for 4 additional weeks, and blood and liver were obtained from all animals for biochemical, histological, and molecular analysis. The MI treatment reduced liver steatosis, decreasing liver weight and hepatic lipid content, and liver injury, as evidenced by a pronounced decrease in serum levels of liver transaminases. Moreover, animals supplemented with the MI cocktail showed a reduction in the gene expression of some proinflammatory cytokines when compared with their HFHFr counterparts. In addition, MI supplementation was effective in decreasing hepatic fibrosis and improving insulin sensitivity, as observed by histological analysis, as well as a reduction in fibrotic gene expression (Col1α1) and improved Akt activation, respectively. Taken together, supplementation with this specific combination of metabolic cofactors ameliorates several features of NAFLD, highlighting this treatment as a potential efficient therapy against this disease in humans.

The consumption of sweet oranges has been linked to several health benefits, many of which are attributed to hesperidin, a flavanone that is present in high amounts in these fruits. However, other phenolic compounds can contribute to the bioactivity of sweet orange. To link those effects to their phenolic profile, the complete characterization of the phenolic profile is mandatory. Although many studies have profiled the phenolic composition of orange juices, their pulps, which retain phenolic compounds, are overlooked. This fact is particularly relevant because dietary guidelines recommend the consumption of whole fruits. Therefore, this study aimed to develop a specific method for the optimal extraction of phenolics from orange pulp and to use this method to characterize these fruits grown at different locations by HPLC-ESI-MS/MS. The extraction conditions that reported the highest total polyphenol content (TPC) and hesperidin contents were 20 mL/g, 55 °C, and 90% methanol. The extraction time and number of sequential steps were further evaluated and optimized as 20 min and two extraction steps, respectively. Although lower extraction rates were achieved when using ethanol as the extraction solvent, high TPC and hesperidin yields were obtained, suggesting the potential use of this methodology to produce phenolic-rich extracts for the food industry. By applying the optimized methodology and analyzing the extracts by HPLC-ESI-MS/MS, geographic cultivation regions were demonstrated to affect the phenolic profiles of oranges. In short, we developed a quick, easy-to-perform methodology that can be used to extract orange phenolics from pulp for their identification and quantification and to evaluate the factors that affect the phenolic profile in sweet orange pulps.

The antihypertensive effect of the soluble fraction of wine lees (WL) from Cabernet variety grapes was recently reported by our group. This blood pressure (BP)-lowering effect was attributed to the presence of flavanols and anthocyanins. In this context, phenolic-enriched wine lees (PWL) could potentially exhibit a stronger bioactivity. Therefore, the aim of this study was to obtain a soluble fraction of WL with increased phenolic content and evaluate its functionality. The PWL were obtained using an enzyme-assisted extraction based on the hydrolysis of WL proteins with Flavourzyme®. They contained 57.20% more total phenolic compounds than WL, with anthocyanins and flavanols being the largest families present. In addition, PWL also showed greater angiotensin-converting enzyme inhibitory and antioxidant activities. Finally, the antihypertensive activity of the PWL was evaluated in spontaneously hypertensive rats. A single dose of 5 mL/kg body weight of PWL showed a greater BP-lowering effect than the one shown by WL. Moreover, this antihypertensive effect was more prolonged than the one produced by the antihypertensive drug Captopril. These results demonstrate that enzymatic protein hydrolysis is a useful method to maximize the extraction of phenolic compounds from WL and to obtain extracts with enhanced functionalities.

III Congreso de Alimentación, Nutrición y Dietética. Combinar la nutrición comunitaria y personalizada: nuevos retos.

The data included here support the research article “Circulating endothelial microparticles are elevated in bicuspid aortic valve (BAV) disease and related to aortic dilation” (Alegret et al., 2016 [1]) where circulating levels of platelet endothelial cell adhesion molecule (PECAM+) endothelial microparticles (EMPs) were identified as a biological variable related to aortic dilation in patients with BAV disease. The data presented in this article are composed by four tables and one figure containing the clinical and echocardiographic characteristics of the patients (Alegret et al., 2016 [1]) included in this study, and summarize the results of multivariate linear analyses. Furthermore, is also included a figure showing a representative flow cytometry dot plots and histograms used in PECAM+ EMPs quantification is also included.

The peptide AVFQHNCQE demonstrated to produce nitric oxide-mediated antihypertensive effect. This study investigates the bioavailability and the opioid-like activity of this peptide after its oral administration. For this purpose, in silico and in vitro approaches were used to study the peptide susceptibility to GI digestion. In addition, AVFQHNCQE absorption was studied both in vitro by using Caco-2 cell monolayers and in vivo evaluating peptide presence in plasma from Wistar rats by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and by ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Both in vivo and in vitro experiments demonstrated that peptide AVFQHNCQE was not absorbed. Thus, the potential involvement of opioid receptors in the BP-lowering effect of AVFQHNCQE was studied in the presence of opioid receptors-antagonist Naloxone. No changes in blood pressure were recorded in rats administered Naloxone, demonstrating that AVFQHNCQE antihypertensive effect is mediated through its interaction with opioid receptors. AVFQHNCQE opioid-like activity would clarify the antihypertensive properties of AVFQHNCQE despite its lack of absorption.

Although nickel allergy and carcinogenicity are well known, their molecular mechanisms are still uncertain, thus demanding studies at the molecular level. The nickel carcinogenicity is known to be dependent on the chemical form of nickel, since only certain nickel compounds can enter the cell. This study investigates, for the first time, the cytotoxicity, cellular uptake, and molecular targets of nickel nanoparticles (NiNPs) in human skin cells in comparison with other chemical forms of nickel. The dose-response curve that was obtained for NiNPs in the cytotoxicity assays showed a linear behavior typical of genotoxic carcinogens. The exposure of keratinocytes to NiNPs leads to the release of Ni2+ ions and its accumulation in the cytosol. A 6 kDa nickel-binding molecule was found to be synthesized by cells exposed to NiNPs at a dose corresponding to medium mortality. This molecule was identified to be tumor-related p63-regulated gene 1 protein.

Circadian rhythms are ~24 h fluctuations of different biological processes that are regulated by the circadian clock system. They exert a major influence on most of the metabolism, such as the hepatic metabolism. This rhythmicity can be disrupted by obesogenic diets, fact that is considered to be a risk factor for the development of metabolic diseases. Nevertheless, obesogenic diets do not affect both genders in the same manner. We hypothesized that the circadian rhythms disruption of the hepatic metabolism, caused by obesogenic diets, is gender-dependent. Male and female Fischer 344 rats were fed either a standard diet or a cafeteria diet and sacrificed at two different moments, at zeitgeber 3 and 15. Only female rats maintained the circadian variations of the hepatic metabolism under a cafeteria diet. Most of those metabolites were related with the very low density lipoprotein (VLDL) synthesis, such as choline, betaine or phosphatidylcholine. Most of these metabolites were found to be increased at the beginning of the dark period. On the other hand, male animals did not show these time differences. These findings suggest that females might be more protected against the circadian disruption of the hepatic metabolism caused by a cafeteria diet through the increase of the VLDL synthesis at the beginning of the feeding time.

Conjugated linoleic acid (CLA) is a dietary supplement that has been shown to improve obesity. However, some authors have associated high doses of CLA supplementation with liver impairment and insulin resistance. The aim of this study was to assess whether the consumption of low doses of CLA maintained the beneficial effects on the main metabolic disturbances associated with metabolic syndrome (MetS) but prevented the occurrence of non-desirable outcomes associated with its consumption. Male Wistar rats, fed standard or cafeteria (CAF) diet for 12 weeks, were supplemented with three different low doses of CLA in the last three weeks. Both biochemical and H1 NMR-based metabolomics profiles were analysed in serum and liver. The consumption of 100 mg/kg CLA, but not doses of 200 and 300 mg/kg, ameliorated the increase in body weight gain as well as the serum concentrations of glucose, insulin, cholesterol, triglyceride, diglyceride, and total phospholipid induced by a CAF diet. In turn, CLA reverted the increase in lactate, alanine, and glucose concentrations in the liver of these animals, but enhanced hepatic cholesterol accumulation without any detrimental effect on liver function. In conclusion, a low dose of CLA corrected the adverse effects associated with MetS without compromising other metabolic parameters.

Non-Alcoholic Fatty Liver Disease (NAFLD) is the most common liver disease in the world. NAFLD is principally characterized by an excessive fat accumulation in the hepatocytes. Diet is considered as one of the main drivers to modulate the composition of gut microbiota, which participate in different processes, affecting human metabolism. A disruption in the homeostasis of gut microbiota may lead to dysbiosis, which is commonly reflected by a reduction of the beneficial species and an increment in pathogenic microbiota. Gut and liver are in close relation due to the anatomical and functional interactions led by the portal vein, thus altered intestinal microbiota might affect liver functions, promoting inflammation, insulin resistance and steatosis, which is translated into NAFLD. This review will highlight the association between diet, gut microbiota and liver, and how this axis may promote the development of NAFLD progression, discussing potential mechanisms and alterations due to the dysbiosis of gut microbiota. Finally, it will revise the variations in gut microbiota composition in NAFLD, and it will focus in specific species, which directly affect NAFLD progression.

Biological rhythms can influence the activity of bioactive compounds, and at the same time, the intake of these compounds can modulate biological rhythms. In this context, chrononutrition has appeared as a research field centered on the study of the interactions among biological rhythms, nutrition, and metabolism. This review summarizes the role of phenolic compounds in the modulation of biological rhythms, focusing on their effects in the treatment or prevention of chronic diseases. Heterotrophs are able to sense chemical cues mediated by phytochemicals such as phenolic compounds, promoting their adaptation to environmental conditions. This is called xenohormesis. Hence, the consumption of fruits and vegetables rich in phenolic compounds exerts several health benefits, mainly attributed to the product of their metabolism. However, the profile of phenolic compounds present in plants differs among species and is highly variable depending on agricultural and technological factors. In this sense, the seasonal consumption of polyphenol-rich fruits could induce important changes in the regulation of physiology and metabolism due to the particular phenolic profile that the fruits contain. This fact highlights the need for studies that evaluate the impact of these specific phenolic profiles on health to establish more accurate dietary recommendations.

AVFQHNCQE is an antihypertensive nonapeptide obtained from a chicken foot protein hydrolysate. The present study aims to investigate the mechanisms involved in its blood pressure (BP)-lowering effect. Male (17⁻20 weeks old) spontaneously hypertensive rats (SHR) were used in this study. Rats were divided into two groups and orally administered water or 10 mg/kg body weight (bw) AVFQHNCQE. One hour post-administration, animals of both groups were intra-peritoneally treated with 1 mL of saline or with 1 mL of saline containing 30 mg/kg bw Nω-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) synthesis, or with 1 mL of saline containing 5 mg/kg bw indomethacin, which is an inhibitor of prostacyclin synthesis (n = 6 per group). Systolic BP was recorded before oral administration and six hours after oral administration. In an additional experiment, SHR were administered water or 10 mg/kg bw AVFQHNCQE (n = 6 per group) and sacrificed six hours post-administration to study the mechanisms underlying the peptide anti-hypertensive effect. Moreover, the relaxation caused by AVFQHNCQE in isolated aortic rings from Sprague-Dawley rats was evaluated. The BP-lowering effect of the peptide was not changed after indomethacin administration but was completely abolished by L-NAME, which demonstrates that its anti-hypertensive effect is mediated by changes in endothelium-derived NO availability. In addition, AVFQHNCQE administration downregulated aortic gene expression of the vasoconstrictor factor endothelin-1 and the endothelial major free radical producer NADPH. Moreover, while no changes in plasma ACE activity were observed after its administration, liver GSH levels were higher in the peptide-treated group than in the water group, which demonstrates that AVFQHNCQE presents antioxidant properties.

Bioactive compounds such as polyphenols have increased in importance in recent years, and among them, resveratrol (3,5,4′-trihydroxy-trans-stilbene) has generated great interest as an anti-obesity agent. Recent investigations have highlighted the importance of leptin signaling in lipid metabolism in peripheral organs. The aims of this study were (1) to investigate whether resveratrol can reduce fat accumulation in peripheral tissues by increasing their leptin sensitivity and (2) to identify which resveratrol-derived circulating metabolites are potentially involved in these metabolic effects. Serum leptin levels and the leptin signaling pathway were assessed in diet-induced obese rats. Moreover, serum metabolites of resveratrol were studied by ultra-high performance liquid chromatography⁻mass spectrometry (UHPLC-MSn). The daily consumption of 200 mg/kg of resveratrol, but not doses of 50 and 100 mg/kg, reduced body weight and fat accumulation in obese rats and restored leptin sensitivity in the periphery. These effects were due to increases in sirtuin 1 activity in the liver, leptin receptors in muscle and protection against endoplasmic reticulum (ER)-stress in adipose tissue. In general, the resveratrol metabolites associated with these beneficial effects were derived from both phase II and microbiota metabolism, although only those derived from microbiota increased proportionally with the administered dose of resveratrol. In conclusion, resveratrol reversed leptin resistance caused by diet-induced obesity in peripheral organs using tissue-specific mechanisms.

Hereditary hemochromatosis (HH) is characterized by accumulation of iron, oxidative stress, inflammation, and fibrogenesis in liver tissue. In this setting, research on the protection afforded by intracellular antioxidants is of clinical relevance. Paraoxonase-1 (PON1) is an enzyme that degrades lipid peroxides. This study investigates the alterations in serum PON1 status, PON1 gene polymorphisms, and PON1 hepatic expression in patients with HH. We performed a case-control study in 77 patients with HH (80.5% men, 22–70 years of age) and 408 healthy individuals (43.1% men, 26–74 years of age). Serum PON1 activities against different substrates and PON1192 and PON155 polymorphisms were analyzed. PON1 protein expression was investigated in 20 liver biopsies. HH patients had significantly lower serum PON1 activity, which was inversely correlated with ferritin (marker of iron stores) and serum 8-isoprostane concentrations (index of oxidative stress). PON1 protein expression in liver tissue was higher in patients and showed stronger staining in hepatocytes surrounding the areas of inflammation. Our study provides preliminary evidence that PON1 may play a role in protecting against iron-induced oxidative stress in hereditary hemochromatosis.

We investigated the influence of the HIV infection on serum paraoxonase-3 (PON3) concentration and assessed the relationships with lipoprotein-associated abnormalities, immunological response, and accelerated atherosclerosis. We studied 207 HIV-infected patients and 385 healthy volunteers. Serum PON3 was determined by in-house ELISA, and PON3 distribution in lipoproteins was investigated by fast-performance liquid chromatography (FPLC). Polymorphisms of the PON3 promoter were analyzed by the Iplex Gold MassArrayTM method. PON3 concentrations were increased (about three times) in HIV-infected patients with respect to controls (P < 0.001) and were inversely correlated with oxidized LDL levels (P = 0.038). Long-term use of nonnucleoside reverse transcriptase inhibitor (NNRTI)-based antiretroviral therapy was associated with a decrease of PON3 concentrations. In a multivariate linear regression analysis, these relationships were still strong when the main confounding covariates were considered. PON3 was mainly found in HDL in HIV-infected patients, but a substantial amount of the protein was detected in LDL particles. This study reports for the first time an important increase in serum PON3 concentrations in HIV-infected patients that is associated with their oxidative status and their treatment with NNRTI. Long-term, prospective studies are needed to confirm the possible influence of this enzyme on the course of this disease and its possible utility as an analytical biomarker.

Experimental studies showed that paraoxonase-3 (PON3) retards lipoprotein oxidation. Our objective was to describe a new assay to measure serum PON3 concentrations and report their reference values in a population-based study. The influence of PON3 promoter polymorphisms and their relationships with PON1 and lipid profile were also studied. We generated an anti-PON3 antibody by inoculating rabbits with a synthetic peptide specific to mature PON3. This antibody was used to develop an ELISA. The average regression line of standard plots (n = 8) was y = 0.9587 (0.3392) log10x + 1.9466 (0.0861) [r2= 0.924 (0.0131); P < 0.001]. There was no cross reaction with PON1. Detection limit was 0.24 mg/l. Imprecision was ≤13.2%. Reference interval (n = 356) was 1.00-2.47 mg/l. PON3 was observed in HDL particles containing apolipoprotein (apo)A-I and PON1, but not apoA-II or apoE. Serum PON3 concentrations showed a moderate influence (about 10% variation) by PON3 promoter polymorphisms. Our study describes for the first time a method to measure serum PON3 concentrations. This method offers new opportunities in the investigation of the properties and role of PON3 in cardiovascular disease, with possible implications in clinical practice.

Excessive energy management leads to low-grade, chronic inflammation, which is a significant factor predicting noncommunicable diseases. In turn, inflammation, oxidation, and metabolism are associated with the course of these diseases; mitochondrial dysfunction seems to be at the crossroads of mutual relationships. The migration of immune cells during inflammation is governed by the interaction between chemokines and chemokine receptors. Chemokines, especially C-C-chemokine ligand 2 (CCL2), have a variety of additional functions that are involved in the maintenance of normal metabolism. It is our hypothesis that a ubiquitous and continuous secretion of CCL2 may represent an animal model of low-grade chronic inflammation that, in the presence of an energy surplus, could help to ascertain the afore-mentioned relationships and/or to search for specific therapeutic approaches. Here, we present preliminary data on a mouse model created by using targeted gene knock-in technology to integrate an additional copy of the CCl2 gene in the Gt(ROSA)26Sor locus of the mouse genome via homologous recombination in embryonic stem cells. Short-term dietary manipulations were assessed and the findings include metabolic disturbances, premature death, and the manipulation of macrophage plasticity and autophagy. These results raise a number of mechanistic questions for future study.

We investigated the potential differential effects of antiretroviral therapies on unbalanced chemokine homeostasis and on the progression of atherosclerosis in HIV-infected patients. A two-year prospective study was performed in 67 consecutive HIV-infected patients initiating antiretroviral therapy with abacavir/lamivudine or tenofovir/emtricitabine. Circulating levels of inflammatory biomarkers, progression of subclinical atherosclerosis and expression levels of selected chemokines genes in circulating leukocytes were assessed. Control subjects showed significantly lower plasma concentrations of CRP, tPA, IL-6, and MCP-1 than HIV-infected patients at a baseline. After two years of followup, the observed decreases in plasma inflammatory biomarker levels were only significant for MCP-1, tPA, and IL-6. The decrease in plasma MCP-1 concentration was associated with the progression of atherosclerosis, and this effect was negligible only in patients receiving TDF-based therapy. Multivariate analysis confirmed that treatment with TDF was positively and significantly associated with a higher likelihood of subclinical atherosclerosis progression. However, the expression levels of selected genes in blood cells only showed associations with the viral load and total and HDL-cholesterol levels. Current antiretroviral treatments may partially attenuate the influence of HIV infection on certain inflammatory pathways, though patients receiving TDF therapy must be carefully monitored with respect to the presence and/or progression of atherosclerosis.

DING proteins constitute an interesting family, owing to their intriguing and important activities. However, after a decade of research, little is known about these proteins. In humans, at least five different DING proteins have been identified, which were implicated in important biological processes and diseases, including HIV. Indeed, recent data from different research groups have highlighted the anti-HIV activity of some DING representatives. These proteins share the ability to inhibit the transcriptional step of HIV-1, a key step of the viral cycle that is not yet targeted by the current therapies. Since such proteins have been isolated from humans, we undertook a comprehensive study that focuses on the relationship between these proteins and HIV-infection in an infectious context. Hence, we developed a home-made ELISA for the quantification of the concentration of DING proteins in human serum. Using this method, we were able to determine the concentration of DING proteins in healthy and HIV-infected patients. Interestingly, we observed a significant increase of the concentration of DING proteins in non treated and treated HIV-infected patients compared to controls. In addition, cell cultures infected with HIV also show an increased expression of DING proteins, ruling out the possible role of antiretroviral treatment in the increase of the expression of DING proteins. In conclusion, results from this study show that the organism reacts to HIV-infection by an overexpression of DING proteins.

The paraoxonase (PON) group of enzymes, composed of PON1, PON2, and PON3, play an important role in decreasing oxidative stress by degrading lipid peroxides. PON1 synthesis is upregulated by PPAR. Several pharmacological compounds (acting as antioxidants and, hence, atheroprotective) stimulate both PPAR activity and PON1 expression. Recent evidence suggests that PON1 and the monocyte chemoattractant protein-1 (MCP-1) are involved in coordinating the inflammatory response in damaged tissues; PPAR may be central in the regulation of these biochemical pathways. This article reviews the state of knowledge on PON1 biochemistry and function, the influence of genetic variation, and the regulation of PON1 expression by pharmaceutical compounds that increase PPAR activity. We also describe recent lines of evidence suggesting links between PON1 and MCP-1 and how their production may be regulated by PPAR.