How Diet and Lifestyle Can Fine-Tune Gut Microbiomes for Healthy Aging.

Many physical, social, and psychological changes occur during aging that raise the risk of developing chronic diseases, frailty, and dependency. These changes adversely affect the gut microbiota, a phenomenon known as microbe-aging. Those microbiota alterations are, in turn, associated with the development of age-related diseases. The gut microbiota is highly responsive to lifestyle and dietary changes, displaying a flexibility that also provides anactionable tool by which healthy aging can be promoted. This review covers, firstly, the main lifestyle and socioeconomic factors that modify the gut microbiota composition and function during healthy or unhealthy aging and, secondly, the advances being made in defining and promoting healthy aging, including microbiome-informed artificial intelligence tools, personalized dietary patterns, and food probiotic systems.

The gut microbiota urolithin metabotypes revisited: the human metabolism of ellagic acid is mainly determined by aging.

Understanding individuals' response to dietary bioactives is crucial for personalized nutrition. We report here for the first time in a Caucasian cohort (5-90 years, n = 839) that aging is the main factor that determines the gut microbiota involved in the ellagic acid-ellagitannin metabolism (urolithin metabotypes), with potential consequences for human health.

Vasorelaxant activity of twenty-one physiologically relevant (poly)phenolic metabolites on isolated mouse arteries.

Polyphenols are beneficial for health, but are metabolised after consumption. We compared the vasorelaxant capacity of twenty-one physiologically relevant polyphenol metabolites in isolated mouse arteries. Hesperetin, urolithins and ferulic acid-4-O-sulfate - not their glucuronidated forms or ferulic acid - caused vasorelaxation. Therefore, we advise the use of relevant conjugates in future mechanistic research.

Bioavailability of phenolics from an oleuropein-rich olive (Olea europaea) leaf extract and its acute effect on plasma antioxidant status: comparison between pre- and postmenopausal women.

PURPOSE: Preclinical studies suggest a potential protective effect of oleuropein in osteoporosis, and one of the proposed mechanisms is the modulation of the oxidative stress. Oleuropein bioavailability and its effect on antioxidant status in pre- and postmenopausal women are unknown. The aim of the present study was to investigate the oral bioavailability of an olive leaf extract rich in oleuropein (40 %) and its effect on antioxidant status in postmenopausal women compared to premenopausal women. METHODS: Premenopausal (n = 8) and postmenopausal women (n = 8) received 250 mg of olive leaf extract, blood samples (t = 0, 1, 2, 3, 4, 6, 8, 12, 16 and 24 h) were taken, and 24-h urine divided into five fractions was collected. Olive-leaf-extract-derived metabolites were analyzed in plasma and urine by HPLC-ESI-QTOF and UPLC-ESI-QqQ, and pharmacokinetics parameters were determined. Ferric reducing antioxidant ability and malondialdehyde levels were measured in plasma. RESULTS: Plasma levels of hydroxytyrosol glucuronide, hydroxytyrosol sulfate, oleuropein aglycon glucuronide and oleuropein aglycon derivative 1 were higher in postmenopausal women. MDA levels were significantly decreased (32%) in postmenopausal women and inversely correlated with hydroxytyrosol sulfate levels. Postmenopausal women excreted less sulfated metabolites in urine than premenopausal women. CONCLUSIONS: Our results suggest that postmenopausal women could be a target population for the intake of olive phenolics in order to prevent age-related and oxidative stress-related processes such as osteoporosis.

Hepatic molecular responses to Bifidobacterium pseudocatenulatum CECT 7765 in a mouse model of diet-induced obesity.

BACKGROUND AND AIMS: Bifidobacterium pseudocatenulatum CECT 7765 moderates body weight gain and metabolic parameters in high-fat diet-(HFD)-fed mice but, the mechanisms of action are not yet understood. To further understand the effects of this bacterial strain, we have investigated the molecular changes in the liver of mice fed a HFD and supplemented with the bacteria. METHODS AND RESULTS: Gene expression and protein levels were measured in the liver of C57BL/6 male mice following sub-chronic consumption of a HFD and B. pseudocatenulatum CECT 7765. Our results show that the consumption of this bacterial strain modulated the expression of key genes involved in the regulation of energy metabolism and transport of lipids that were affected by the HFD.B. pseudocatenulatum CECT 7765 significantly counteracted the effects caused by the HFD on the fatty acid transporter CD36, the transcription regulator of lipid biosynthesis EGR1 and the regulators of glucose metabolism, IGFBP2 and PPP1R3B, both at the mRNA and protein levels. The bacterial strain slightly induced the transcript levels of PNPLA2, a lipase that hydrolyses triglycerides in lipid droplets. In the standard diet (SD)-fed mice, the administration of B. pseudocatenulatum CECT 7765 donwregulated the expression of INSIG1 and HMGCR critically involved in the regulation of cholesterol levels. CONCLUSION: B. pseudocatenulatum CECT 7765 modified the expression of key regulators of fatty acid and cholesterol metabolism and transport, lipid levels and glucose levels in the liver which supports the beneficial metabolic effects of this bacterial strain.

Urolithins, ellagitannin metabolites produced by colon microbiota, inhibit Quorum Sensing in Yersinia enterocolitica: Phenotypic response and associated molecular changes.

The mammalian enteropathogen Yersinia enterocolitica produces two main N-acylhomoserine lactones (AHLs) involved in Quorum Sensing (QS)-mediated infection processes, such as virulence, biofilm maturation and motility. Ellagitannin (ET)-rich fruits exhibit anti-QS activity but in vivo effects against intestinal pathogens may be associated to the ETs gut microbiota derived metabolites, urolithin-A (Uro-A) and urolithin-B (Uro-B). In this work we show that urolithins, at concentrations achievable in the intestine through the diet, reduce the levels of N-hexanoyl-l-homoserine lactone (C6-HSL) and N-(3-oxo-hexanoyl)-l-homoserine lactone (3-oxo-C6-HSL) in Y. enterocolitica and inhibit QS-associated biofilm maturation and swimming motility. These inhibitory effects were not associated to downregulation of the expression of some of the genes involved in the synthesis of AHLs (yenI and yenR) or in motility (flhDC, fliA, fleB). Our results suggest that urolithins may exert antipathogenic effects in the gut against Y. enterocolitica and highlight the need to investigate the antipathogenic in vivo properties of plant derived metabolites.

Lack of effect of oral administration of resveratrol in LPS-induced systemic inflammation.

PURPOSE: The high mortality index due to sepsis and the lack of an effective treatment requires the search for new compounds that can serve as therapy for this disease. Resveratrol, a well-known anti-inflammatory natural compound, might be a good candidate for the treatment of sepsis. The aim of this work was to study the effects of oral administration of resveratrol, before and after sepsis initiation, on inflammation markers in a murine model of endotoxin-induced sepsis. METHODS: Sprague-Dawley male rats were treated with resveratrol the 3 days prior to LPS administration and 45 min later. Hematological parameters, TNF-α, IL-1ß and CINC-1, FRAP and TBARS levels were determined. Resveratrol and resveratrol-derived metabolites profile in plasma was compared after oral and intraperitoneal administration. RESULTS: Oral treatment with resveratrol had no apparent systemic protective effects. However, resveratrol reduced the levels of lipid peroxidation in the small intestine and colon. Importantly, the administration of LPS caused a decrease in resveratrol absorption. When resveratrol bioavailability after i.p. administration was compared to that observed after oral administration, a different profile of resveratrol metabolites was found in plasma. CONCLUSION: These results highlight the importance of studying the bioavailability of the assayed compounds in the experimental models used to be able to choose the best route of administration depending on the target organ and to determine which compounds or derived metabolites are effective treating the studied disease.

Voltammetric behaviour and square-wave voltammetric determination of the potent antioxidant and anticarcinogenic agent ellagic acid in foodstuffs.

The voltammetric behaviour of ellagic acid (EA) is investigated by cyclic, differential pulse and square-wave voltammetry (CV, DPV and SWV, respectively). Based on the anodic oxidation peak at approximately 0.42V in acetic/acetate buffer (pH 5.5) a robust and a highly reliable square-wave voltammetric method is presented for the determination of EA. The oxidation peak current was linearly dependent on the concentration of EA in the range of 1.0×10(-7)-1.5×10(-6)mol/L (r=0.9997), with a detection limit of 1.0×10(-8)mol/L (S/N=3) and a quantification limit of 3.4×10(-8)mol/L (S/N=10), good reproducibility and a satisfactory level of selectivity towards others polyphenols. The proposed method was applied to the determination of free and total EA in fruits, nuts and juices with good analytical results being obtained.

Characterization of C-glycosyl flavones O-glycosylated by liquid chromatography-tandem mass spectrometry.

Fifty three O-glycosyl-C-glycosyl flavones with O-glycosylation on phenolic hydroxyl or on the C-glycosyl residue or combination of both forms have been studied by liquid chromatography-UV diode array detection-electrospray ionisation mass spectrometry ion trap in the negative mode. The study of the relative abundance of the main ions from the MS preferential fragmentation on -MS2 and/or -MS3 events allows the differentiation of the position of the O-glycosylation, either on phenolic hydroxyl or on the sugar moiety of C-glycosylation. In addition, it is possible to discriminate between O-glycosylation at 2'' and at 6'' positions. The occurrence of an abundant ion Y(0)(-) ([(M-H)-132/-146/-162](-), mono-O-pentosyl/rhamnosyl/hexosyl-C-glycosyl derivatives) after -MS2 fragmentation characterizes the O-glycosylation on phenolic hydroxyls. The preferential fragmentation leading to a relevant Z(1)(-) ([Y(1)-18](-)) fragment is characteristic of 2''-O-glycosyl-C-glycosyl derivatives. The 6''-O-glycosyl-C-glycosyl derivatives are characterized by (0,2)X(0)(-), which is generated by a global loss of the sugar moiety from the O-glycosylation at 6'' and the glycosidic fraction that involves the carbons 6''-3'' of the C-glycosyl residue ([(M-H)-162-120](-), in the case of 6''-O-hexosyl-C-hexosyl derivatives). Regarding the combined O-glycosylated compounds (both on phenolic hydroxyl and on sugar moiety at C-glycosylation), the main fragmentation on -MS2 events produces a Y(0)(-) characterizing the O-glycosylation on the phenolic hydroxyl, and the -MS3[(M-H)-->Y(0)](-) fragmentation of the O-glycosylation on the C-glycosyl residue.

Transcriptional changes in human Caco-2 colon cancer cells following exposure to a recurrent non-toxic dose of polyphenol-rich chokeberry juice.

Berries and red fruits are important dietary sources of polyphenols [1]. In vitro and animal studies have demonstrated the bioavailability and the anti-proliferative and anticarcinogenic properties of these fruits or of their phenolic components [2, 3]. Consumption of berries may contribute to the reduction of colon cancer by mechanisms not yet understood. Gene expression analysis using microarrays allows for a more comprehensive study of the possible molecular mechanisms by which food or food components may prevent certain cancers of the gastrointestinal tract [4]. The aim of this research is to investigate the anti-proliferative effects of a polyphenol-rich berry juice on a human model of colon cancer cells and its association to transcriptional changes in relation to colon cancer.

Effect of mediterranean forest parasite with Curculio sp. on nutritional value of acorn for Iberian pig feeding and fat characteristics.

Sixteen Iberian barrows of the same age with an average initial live weight of 100.1kg were randomly distributed in two groups of eight pigs each. One group was fed healthy acorns and the other group received acorns infested of Curculio sp. The subcutaneous backfat from pigs fed healthy acorns had higher C18:1n-9, MUFA and C20:5n-3 and lower C18:0 and SFA proportions than that from the pigs fed acorns infested with Curculio. The consumption of acorns infested with Curculio sp. led to a reduction of C18:1n-9, MUFA, C18:2n-6, C18:3n-3, C22:5n-3 and PUFA proportions in neutral lipids from Longissimus dorsi muscle with respect to consumption of healthy acorns, whereas in polar lipids it produced a reduction in C18:1n-9, MUFA and C18:4n-3 proportions and an increase in C18:2n-6, C20:4n-6, n-6 and C20:5n-3 proportions and of n-6/n-3 ratio with respect to the healthy acorns consumption. The pigs fed healthy acorns had higher intramuscular fat percentage in Longissimus dorsi than pigs fed with acorns infested with Curculio (9.95 vs 7.09% SEM=0.60).

The flavonoid glycosides and procyanidin composition of Deglet Noor dates (Phoenix dactylifera).

The fruits of the date palm (Phoenix dactylifera) are consumed throughout the world and are an important part of the diet in the Middle East. Dates at the rutab and tamar maturity and ripening stages contain a wide array of phenolic antioxidants, but little is known about the composition of phenolic compounds in dates at the khalal stage of ripening. In the current study, the flavonoid glycoside and procyanidin compositions of dates of the cultivar Deglet Noor harvested at the khalal stage of maturity were characterized using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI/MS/MS). Procyanidin oligomers through decamers were identified in extracts of these dates. Higher molecular weight polymers, undecamers through heptadecamers, were also apparent from mass spectra. Thirteen flavonoid glycosides of luteolin, quercetin, and apigenin, 19 when considering isomeric forms, were also identified. Mass spectra indicate that both methylated and sulfated forms of luteolin and quercetin are present as mono-, di-, and triglycosylated conjugates whereas apigenin is present as only the diglycoside. LC-ESI/MS/MS spectra indicate that quercetin and luteolin formed primarily O-glycosidic linkages whereas apigenin is present as the C-glycoside.

Pomegranate juice supplementation in chronic obstructive pulmonary disease: a 5-week randomized, double-blind, placebo-controlled trial.

OBJECTIVE: The aim of the present study is to investigate the effect of antioxidant polyphenol-rich pomegranate juice (PJ) supplementation for 5 weeks on patients with stable chronic obstructive pulmonary disease (COPD), since the oxidative stress plays a major role in the evolution and pathophysiology of COPD. DESIGN: A randomized, double-blind, placebo-controlled trial was conducted. SUBJECTS: A total of 30 patients with stable COPD were randomly distributed in two groups (15 patients each). INTERVENTIONS: Both groups consumed either 400 ml PJ daily or matched placebo (synthetic orange-flavoured drink) for 5 weeks. Trolox Equivalent Antioxidant Capacity (TEAC) of PJ, blood parameters (14 haematological and 18 serobiochemical), respiratory function variables, bioavailability of PJ polyphenols (plasma and urine) and urinary isoprostane (8-iso-PGF(2alpha)) were evaluated. RESULTS: The daily dose of PJ (containing 2.66 g polyphenols) provided 4 mmol/l TEAC. None of the polyphenols present in PJ were detected in plasma or in urine of volunteers. The most abundant PJ polyphenols, ellagitannins, were metabolized by the colonic microflora of COPD patients to yield two major metabolites in both plasma and urine (dibenzopyranone derivatives) with no TEAC. No differences were found (P > 0.05) between PJ and placebo groups for any of the parameters evaluated (serobiochemical and haematological), urinary 8-iso-PGF(2alpha), respiratory function variables and clinical symptoms of COPD patients. CONCLUSIONS: Our results suggest that PJ supplementation adds no benefit to the current standard therapy in patients with stable COPD. The high TEAC of PJ cannot be extrapolated in vivo probably due to the metabolism of its polyphenols by the colonic microflora. The understanding of the different bioavailability of dietary polyphenols is critical before claiming any antioxidant-related health benefit. SPONSORSHIP: 'Fundación Séneca' (Murcia, Spain), Project PB/18/FS/02 and Spanish CICYT, Project AGL2003-02195.

Characterisation of flavonols in broccoli (Brassica oleracea L. var. italica) by liquid chromatography-uV diode-array detection-electrospray ionisation mass spectrometry.

The flavonoid composition of broccoli inflorescences has been studied by LC/UV-DAD/ESI-MSn. A large number of hydroxycinnamic acid esters of kaempferol and quercetin glucosides has been characterised. The structures of the flavonoid glycosides were analysed after alkaline hydrolysis, and were identified as 3-sophoroside/sophorotrioside-7-glucoside/sophoroside of kaempferol, quercetin and isorhamnetin (this last found in trace amount). These complex quercetin and isorhamnetin glucosides have not been previously characterised in nature. In addition, several less complex glucosides based on the same aglycones have been identified. The effect of sugar substitution and acylation on chromatographic mobility and ESI ionisation and fragmentation are discussed.

Flavonoids in food and their health benefits.

There has been increasing interest in the research of flavonoids from dietary sources, due to growing evidence of the versatile health benefits of flavonoids through epidemiological studies. As occurrence of flavonoids is directly associated with human daily dietary intake of antioxidants, it is important to evaluate flavonoid sources in food. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. However, there is still difficulty in accurately measuring the daily intake of flavonoids because of the complexity of existence of flavonoids from various food sources, the diversity of dietary culture, and the occurrence of a large amount of flavonoids itself in nature. Nevertheless, research on the health aspects of flavonoids for humans is expanding rapidly. Many flavonoids are shown to have antioxidative activity, free-radical scavenging capacity, coronary heart disease prevention, and anticancer activity, while some flavonoids exhibit potential for anti-human immunodeficiency virus functions. As such research progresses. further achievements will undoubtedly lead to a new era of flavonoids in either foods or pharmaceutical supplements. Accordingly, an appropriate model for a precise assessment of intake of flavonoids needs to be developed. Most recent research has focused on the health aspects of flavonoids from food sources for humans. This paper reviews the current advances in flavonoids in food, with emphasis on health aspects on the basis of the published literature, which may provide some guidance for researchers in further investigations and for industries in developing practical health agents.

HPLC-DAD-ESIMS analysis of phenolic compounds in nectarines, peaches, and plums.

The phenolic compounds of 25 peach, nectarine, and plum cultivars were studied and quantified by HPLC-DAD-ESIMS. Hydroxycinnamates, procyanidins, flavonols, and anthocyanins were detected and quantified. White and yellow flesh nectarines and peaches, and yellow and red plums, were analyzed at two different maturity stages with consideration of both peel and flesh tissues. HPLC-MS analyses allowed the identification of procyanidin dimers of the B- and A-types, as well as the presence of procyanidin trimers in plums. As a general rule, the peel tissues contained higher amounts of phenolics, and anthocyanins and flavonols were almost exclusively located in this tissue. No clear differences in the phenolic content of nectarines and peaches were detected or between white flesh and yellow flesh cultivars. There was no clear trend in phenolic content with ripening of the different cultivars. Some cultivars, however, had a very high phenolic content. For example, the white flesh nectarine cultivar Brite Pearl (350-460 mg/kg hydroxycinnamates and 430-550 mg/kg procyanidins in flesh) and the yellow flesh cv. Red Jim (180-190 mg/kg hydroxycinnamates and 210-330 mg/kg procyanidins in flesh), contained 10 times more phenolics than cultivars such as Fire Pearl (38-50 mg/kg hydroxycinnamates and 23-30 mg/kg procyanidins in flesh). Among white flesh peaches, cultivars Snow King (300-320 mg/kg hydroxycinnamates and 660-695 mg/kg procyanidins in flesh) and Snow Giant (125-130 mg/kg hydroxycinnamates and 520-540 mg/kg procyanidins in flesh) showed the highest content. The plum cultivars Black Beaut and Angeleno were especially rich in phenolics.

Postharvest induction modeling method using UV irradiation pulses for obtaining resveratrol-enriched table grapes: a new "functional" fruit?

A modeling method for the induction of resveratrol synthesis by UV irradiation pulses in Napoleon table grapes is proposed. The method is based on the combination of four main parameters: irradiation power (IW), irradiation time (IT), irradiation distance (ID), and number of elapsed days to achieve the highest resveratrol accumulation (D(m)). Maximum resveratrol content (11-fold higher than untreated grapes) was achieved using the combination: IW = 510 W, IT = 30 s, ID = 40 cm, and D(m) = 3 days. Sensory characteristics and main features of irradiated grapes (color, weight, firmness, flavor, size, ripening index and vitamin C content) remained unaltered after 1 week of storage. UV induction signal migrated to the hidden side of the grape skin with a delay of 3 days as compared to the directly irradiated side. Phenolic compounds were not detected in Napoleon grape flesh. Resveratrol content per standard serving (200 g) of irradiated grape was about 3 mg, an amount more than 10-fold higher than that of untreated Napoleon grapes. This means that a serving of irradiated grape (unpeeled) could supply the resveratrol content equivalent to 3 glasses of a red wine with high resveratrol content ( approximately 1 mg/glass). Therefore, controlled UV irradiation pulses are useful as a simple postharvest treatment (and alternative to genetic engineering) to obtain possible "functional" grapes (with enhanced health-promoting properties) as a dietary source of high resveratrol content.

Effect of processing and storage on the antioxidant ellagic acid derivatives and flavonoids of red raspberry (Rubus idaeus) jams.

From red raspberries, ellagic acid, its 4-arabinoside, its 4' (4' '-acetyl) arabinoside, and its 4' (4' '-acetyl)xyloside, as well as quercetin and kaempferol 3-glucosides, were identified. In addition, two unidentified ellagic acid derivatives were detected. The free radical scavenging activity of the ellagic acid derivatives was evaluated by using the DPPH method and compared to that of Trolox. All of the isolated compounds showed antioxidant activity. The effect of processing to obtain jams on raspberry phenolics was evaluated. The flavonol content decreased slightly with processing and more markedly during storage of the jams. The ellagic acid derivatives, with the exception of ellagic acid itself, remained quite stable with processing and during 6 months of jam storage. The content of free ellagic acid increased 3-fold during the storage period. The initial content (10 mg/kg of fresh weight of raspberries) increased 2-fold with processing, and it continued increasing up to 35 mg/kg after 1 month of storage of the jam. Then a slight decrease was observed until 6 months of storage had elapsed. The increase observed in ellagic acid could be explained by a release of ellagic acid from ellagitannins with the thermal treatment.

Synthesis of the antioxidant hydroxytyrosol using tyrosinase as biocatalyst.

Hydroxytyrosol (HTyr), a natural ortho-diphenolic antioxidant with health-beneficial properties that mainly occurs in virgin olive oil and olive oil mill waste waters (also known as vegetative waters), has been enzymatically synthesized using mushroom tyrosinase. This o-diphenol (not commercially available) was obtained from its monophenolic precursor tyrosol (commercially available) in the presence of both tyrosinase and ascorbic acid. The reaction synthesis is continuous, easy to perform, and adaptable to a bioreactor for industrial purposes. The HTyr concentration is time-predicted, and the yield of reaction can be 100%. The synthesis method reported here is an alternative approach to obtain this compound in an environmentally friendly way.

In vitro availability of flavonoids and other phenolics in orange juice.

Hand-squeezed navel orange juice contains 839 mg/L phenolics, including flavanones, flavones, and hydroxycinnamic acid derivatives. The flavanones are the main phenolics in the soluble fraction (648.6 mg/L) and are also present in the cloud fraction (104.8 mg/L). During refrigerated storage of fresh juice (4 degrees C), 50% of the soluble flavanones precipitate and integrate into the cloud fraction. Commercial orange juices contain only 81-200 mg/L soluble flavanones (15-33%) and the content in the cloud is higher (206-644 mg/L) (62-85%), showing that during industrial processing and storage the soluble flavanones precipitate and are included in the cloud. An in vitro simulation of orange juice digestion shows that a serving of fresh orange juice (240 mL) provides 9.7 mg of soluble hesperidin (4'-methoxy-3',5,7-trihydroxyflavanone-7-rutinoside) and 4.7 mg of the C-glycosylflavone vicenin 2 (apigenin, 6,8-di-C-glucoside) for freshly squeezed orange juice, whereas pasteurized commercial juices provide 3.7 mg of soluble hesperidin and a higher amount of vicenin 2 (6.3 mg). This means that although orange juice is a very rich source of flavanones, only a limited quantity is soluble, and this might affect availability for absorption (11-36% of the soluble flavanones, depending on the juice). The flavanones precipitated in the cloud are not available for absorption and are partly transformed to the corresponding chalcones during the pancreatin-bile digestion.