30 research outputs found
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Aronia Berry Supplementation Mitigates Inflammation in T Cell Transfer-Induced Colitis by Decreasing Oxidative Stress
Oxidative stress is involved in the pathogenesis and progression of inflammatory bowel disease. Consumption of aronia berry inhibits T cell transfer colitis, but the antioxidant mechanisms pertinent to immune function are unclear. We hypothesized that aronia berry consumption could inhibit inflammation by modulating the antioxidant function of immunocytes and gastrointestinal tissues. Colitis was induced in recombinase activating gene-1 deficient (Rag1-/-) mice injected with syngeneic CD4+CD62L+ naïve T cells. Concurrent with transfer, mice consumed either 4.5% w/w aronia berry-supplemented or a control diet for five weeks. Aronia berry inhibited intestinal inflammation evidenced by lower colon weight/length ratios, 2-deoxy-2-[18F]fluoro-d-glucose (FDG) uptake, mRNA expressions of tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) in the colon. Aronia berry also suppressed systemic inflammation evidenced by lower FDG uptake in the spleen, liver, and lung. Colitis induced increased colon malondialdehyde (MDA), decreased colon glutathione peroxidase (GPx) activity, reduced glutathione (rGSH) level, and suppressed expression of antioxidant enzymes in the colon and mesenteric lymph node (MLN). Aronia berry upregulated expression of antioxidant enzymes, prevented colitis-associated depletion of rGSH, and maintained GPx activity. Moreover, aronia berry modulated mitochondria-specific antioxidant activity and decreased splenic mitochondrial H2O2 production in colitic mice. Thus, aronia berry consumption inhibits oxidative stress in the colon during T cell transfer colitis because of its multifaceted antioxidant function in both the cytosol and mitochondria of immunocytes
Time of harvest affects United States-grown Aronia mitschurinii berry polyphenols, â—¦Brix, and acidity
The goal of this study was to determine how the date of harvest impacts the quality characteristics of Aronia mitschurinii (A. K. Skvortsov and Maitul.) ‘Viking’ and ‘Galicjanka’ berries. Aronia berries were collected from farms in the Midwestern and Northeastern United States over seven weeks of harvest during 2018, 2019 and 2020. The berries were analyzed for total phenol, anthocyanins, proanthocyanins, sugar, and acid. Aronia berry composition modestly deviated between each year of the study. Berries harvested in 2018 had the highest total phenols and proanthocyanidins, both increasing in content from weeks 1–5 from 15.90 ± 3.15–19.65 mg gallic acid equivalents/g fw, a 24% increase, and 2.22 ± 0.40–2.94 mg (+)-catechin equivalents/g fw, a 32% increase, respectively. Berries harvested in 2019 had the lowest total phenol and proanthocyanidin levels and had increasing anthocyanins until week 4. In 2020, aronia berry proanthocyanidins differed from those in 2018 by having 38% lower levels after the 4th week. Across years, berries had increasing ◦Brix, ◦Brix: acid, and pH throughout the seven weeks of harvest. Additionally, all years had slight, but statistically insignificant decreases in acidity over the harvest period. Moreover, analysis from berries collected in 2019 suggests no significant difference in quality factors between Viking and Galicjanka aronia cultivars. In conclusion, aronia berry total phenols, proanthocyanidins, pH, and berry size can be significantly affected by the growing year and time of harvest. Acidity was impacted more by growing year than harvest week. In contrast, anthocyanins and ◦Brix were consistent between years, but influenced considerably by the week of harvest
Bacteroides thetaiotaomicron Starch Utilization Promotes Quercetin Degradation and Butyrate Production by Eubacterium ramulus
Consumption of flavonoids has been associated with protection against cardiovascular and neurodegenerative diseases. Most dietary flavonoids are subjected to bacterial transformations in the gut where they are converted into biologically active metabolites that are more bioavailable and have distinct effects relative to the parent compounds. While some of the pathways involved in the breakdown of flavonoids are emerging, little it is known about the impact of carbon source availability and community dynamics on flavonoid metabolism. This is relevant in the gut where there is a fierce competition for nutrients. In this study, we show that metabolism of one of the most commonly consumed flavonoids, quercetin, by the gut-associated bacterium Eubacterium ramulus is dependent on interspecies cross-feeding interactions when starch is the only energy source available. E. ramulus can degrade quercetin in the presence of glucose but is unable to use starch for growth or quercetin degradation. However, the starch-metabolizing bacterium Bacteroides thetaiotaomicron, which does not metabolize quercetin, stimulates degradation of quercetin and butyrate production by E. ramulus via cross-feeding of glucose and maltose molecules released from starch. These results suggest that dietary substrates and interactions between species modulate the degradation of flavonoids and production of butyrate, thus shaping their bioavailability and bioactivity, and likely impacting their health-promoting effects in humans
Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies
Systemic chronic inflammation may be a contributing factor to many noncommunicable diseases, including diabetes, cardiovascular disease, and obesity. With the rapid rise of these conditions, identifying the causes of and treatment for chronic inflammation is an important research priority, especially with regard to modifiable lifestyle factors such as diet. An emerging body of evidence indicates that consuming certain foods, including dairy foods like milk, cheese, and yogurt, may be linked to a decreased risk for inflammation. To discuss both broader research on diet and inflammation as well as research on links between individual foods and inflammation, the National Dairy Council sponsored a satellite session entitled "Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies" at the American Society for Nutrition's 2020 LIVE ONLINE Conference. This article, a review based on the topics discussed during that session, explores the links between diet and inflammation, focusing most closely on the relations between intake of dairy fat and dairy foods like milk, cheese, and yogurt, and biomarkers of inflammation from clinical trials. While there is currently insufficient evidence to prove an "anti-inflammatory" effect of dairy foods, the substantial body of clinical research discussed in this review indicates that dairy foods do not increase concentrations of biomarkers of chronic systemic inflammation
Characterization of Ellagitannins, Gallotannins, and Bound Proanthocyanidins from California Almond (Prunus dulcis) Varieties
Extractable and bound proanthocyanidins and hydrolyzable
tannins
were characterized in Nonpareil, Carmel, and Butte almond varieties
from California, with <i>n</i> = 3 samples/variety. Bound
proanthocyanidins were recovered from extracted defatted almond residue
by hydrolysis with 4 N sodium hydroxide and represented 3–21%
of the total proanthocyanidin content among varieties. The bound proanthocyanidins
were recovered primarily as monomers and dimers. In contrast, acid
hydrolysis of extracted almond residue did not yield bound proanthocyanidins.
Hydrolyzable tannins were characterized in aqueous acetone extracts
of defatted almond using two-dimensional TLC and further quantitated
by HPLC following acid hydrolysis. Almond hydrolyzable tannin content
was 54.7 ± 2.3 mg ellagic acid and 27.4 ± 7.3 mg gallic
acid per 100 g almond among varieties. The tannin contents of Nonpareil,
Carmel, and Butte almond varieties were not significantly different.
Thus, bound proanthocyanidins and hydrolyzable tannins significantly
contribute to almond polyphenol content
The kinetic basis for age-associated changes in quercetin and genistein glucuronidation by rat liver microsomes
The dietary bioavailability of the isoflavone genistein is decreased in older rats compared to young adults. Since flavonoids are metabolized extensively by the UDP-glucuronosyltransferases (UGTs), we hypothesized that UGT flavonoid conjugating activity changes with age. The effect of age on flavonoid glucuronidation was determined using hepatic microsomes from male F344 rats. Kinetic models of UGT activity toward the flavonol quercetin and the isoflavone genistein were established using pooled hepatic microsomal fractions of rats at different ages, and glucuronidation rates were determined using individual samples. Intrinsic clearance (
V
max/
K
m) values in 4-, 18- and 28-month-old rats were 0.100, 0.078 and 0.087 ml/min/mg for quercetin-7-
O-glucuronide; 0.138, 0.133 and 0.088 for quercetin-3′-
O-glucuronide; and 0.075, 0.077 and 0.057 for quercetin-4′-
O-glucuronide, respectively. While there were no differences in formation rates of total quercetin glucuronides in individual samples, the production of the primary metabolite, quercetin-7-
O-glucuronide, at 30 μM quercetin concentration was increased from 3.4 and 3.1 nmol/min/mg at 4 and 18 months to 3.8 nmol/min/mg at 28 months, while quercetin-3′-
O-glucuronide formation at 28 months declined by a similar degree (
P≤.05). At 30 and 300 μM quercetin concentration, the rate of quercetin-4′-
O-glucuronide formation peaked at 18 months at 0.9 nmol/min/mg. Intrinsic clearance values of genistein 7-
O-glucuronide increased with age, in contrast to quercetin glucuronidation. Thus, the capacity for flavonoid glucuronidation by rat liver microsomes is dependent on age, UGT isoenzymes and flavonoid structure
Microsomal quercetin glucuronidation in rat small intestine depends on age and segment
UDP-glucuronosyltransferase (UGT) activity toward the flavonoid quercetin and UGT protein were characterized in three equidistant small intestine (SI) segments from 4-, 12-, 18-, and 28-month-old male Fischer 344 rats (n = 8/age) using villin to control for enterocyte content. SI microsomal intrinsic clearance of quercetin was increased 3- to 9-fold from 4 months in the proximal and distal SI at 12 and 18 months. Likewise, at 30 μM quercetin, SI microsomal glucuronidation activity was increased with age: 4.8- and 3.9-fold greater at 18 months than at 4 months. Quercetin UGT regioselectivity was not changed by age. The distal SI preferentially catalyzed glucuronidation at the 7-position, whereas the proximal SI produced the greatest proportion of 4'- and 3'-conjugates. Enterocyte UGT content in different SI segments was not consistently changed with age. In the proximal SI, UGT1A increased 64 and 150% at 12 and 18 months and UGT1A1, UGT1A7, and UGT1A8 were also increased at 12 and 18 months. However, age-related changes in expression were inconsistent in the medial and distal segments. Microsomal rates of quercetin glucuronidation and UGT expression were positively correlated with UGT1A1 content for all pooled samples (r = 0.467) and at each age (r = 0.538-0.598). UGT1A7 was positively correlated with total, 7-O- and 3-O-quercetin glucuronidation at 18 months. Thus, age-related differences in UGT quercetin glucuronidation depend on intestinal segment, are more pronounced in the proximal and distal segments and may be partially related to UGT1A1 and UGT1A7 content
Underutilized Chokeberry (Aronia melanocarpa, Aronia arbutifolia, Aronia prunifolia) Accessions Are Rich Sources of Anthocyanins, Flavonoids, Hydroxycinnamic Acids, and Proanthocyanidins
Polyphenols from underutilized black,
purple, and red aronia (Aronia melanocarpa, Aronia prunifolia, and Aronia arbutifolia) and ‘Viking’
(Aronia mitschurinii) berries were
characterized. Anthocyanin and nonanthocyanin flavonoids were quantitated
by UHPLC-DAD-MS and proanthocyanidins by normal-phase HPLC. On a dry
weight basis, anthocyanins were mainly cyanidin-3-galactoside, highest
in black aronia (3.4–14.8 mg/g) and lowest in red aronia (0.5–0.8
mg/g) as cyandin-3-galactoside equivalents. Berries from ‘Viking’
and the red accession UC021 had substantially more proanthocyanidins
than the other accessions, with 3.3 and 3.8 mg catechin equiv/g, respectively.
Chlorogenic acids and quercetin glycosides were most abundant in purple
UC047 berries, at 17.3 and 1.3 mg/g, respectively. In contrast to
anthocyanin content, total phenol values were highest in berries from
red and purple accessions and attributed to phenolic acid and proanthocyanin
content. Thus, red, purple, and black aronia berries are rich sources
of polyphenols with various levels of polyphenol classes
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Dairy Foods and Dairy Fats: New Perspectives on Pathways Implicated in Cardiometabolic Health
Low-fat and nonfat dairy products have been promoted as part of a healthy dietary pattern by both US dietary guidelines and professional organizations for several decades. The basis for this recommendation stems in part from the putative negative cardiometabolic effects associated with saturated fat consumption. However, as nutrition research has shifted from a single nutrient to a whole-food/dietary pattern approach, the role of dairy foods and dairy fat in the diet-disease relationship is being reexamined. Most observational and experimental evidence does not support a detrimental relationship between full-fat dairy intake and cardiometabolic health, including risks of cardiovascular disease and type 2 diabetes. Indeed, an expanded understanding of the dairy food matrix and the bioactive properties of dairy fats and other constituents suggests a neutral or potentially beneficial role in cardiometabolic health. To consider how consuming dairy foods, including full-fat dairy, is associated with cardiometabolic health, this review provides an innovative perspective on mechanisms that link dairy consumption to 3 main biological systems at the core of metabolic health, the gastrointestinal, hepatic, and vascular systems