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Berries reduce postprandial insulin responses to wheat and rye breads in healthy women

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Authors
Torronen R. Kolehmainen M. Sarkkinen E. Poutanen K. Mykkanen H. Niskanen L.
Journal
J Nutr 143(4):430-6
Abstract

<p>Starch in white wheat bread (WB) induces high postprandial glucose and insulin responses. For rye bread (RB), the glucose response is similar, whereas the insulin response is lower. In vitro studies suggest that polyphenol-rich berries may reduce digestion and absorption of starch and thereby suppress postprandial glycemia, but the evidence in humans is limited. We investigated the effects of berries consumed with WB or RB on postprandial glucose and insulin responses. Healthy females (n = 13-20) participated in 3 randomized, controlled, crossover, 2-h meal studies. They consumed WB or RB, both equal to 50 g available starch, with 150 g whole-berry puree or the same amount of bread without berries as reference. In study 1, WB was served with strawberries, bilberries, or lingonberries and in study 2 with raspberries, cloudberries, or chokeberries. In study 3, WB or RB was served with a mixture of berries consisting of equal amounts of strawberries, bilberries, cranberries, and blackcurrants. Strawberries, bilberries, lingonberries, and chokeberries consumed with WB and the berry mixture consumed with WB or RB significantly reduced the postprandial insulin response. Only strawberries (36%) and the berry mixture (with WB, 38%; with RB, 19%) significantly improved the glycemic profile of the breads. These results suggest than when WB is consumed with berries, less insulin is needed for maintenance of normal or slightly improved postprandial glucose metabolism. The lower insulin response to RB compared with WB can also be further reduced by berries.</p>

Bioactivities of pilot-scale extracted cranberry juice and pomace.

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Authors
Harrison JE, Oomah BD, Diarra MS, Ibarra-Alvarado C
Journal
J Food Process Pres 37(4):356-365
Abstract

Fresh cranberries were processed by two pilot-scale methods to recover juice and extracts from cranberry pomace. Press cake was extracted with three successive ethanol soaks followed by decanting in trial 1 versus one ethanol soak and solvent removal by decanting and compressing with the bladder press in trial 2. Yields and recoveries of juice, dry juice solids, press cake, press cake extractives (PCEs), polyphenolics and antioxidant capacity were determined relative to the input material of fresh cranberries or press cake. PCEs from both processes exhibited strong dose-dependant vasorelaxant effects on rat aorta rings with EC50 of 2.3-3.9 micro g/mL and Emax of 96-98%. PCEs contained three to four times the phenolic acids, tartaric esters and antioxidant activities plus five to 10 times the flavonols and anthocyanins of their respective juice powders. The polyphenolic levels were 121-142, 7-10, 9-11 and 10-19 mg equivalents of catechin, caffeic acid, quercetin and cyanidin-3-glucoside/g of extract, respectively. Antioxidant activities of the PCEs and juices were 201-296 and 64-75 mg trolox equivalents/g powder. Juice yields of 47-58% accounted for only 18-50% of the bioactives recovered from whole fruit. Sequential extraction of the press cake with 95% ethanol and removal of the extract with the bladder press favored high recoveries of polyphenolics with increased antioxidant and vasorelaxant benefits.

Chronic cranberry juice consumption restores cholesterol profiles and improves endothelial function in ovariectomized rats.

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Authors
Yung LM, Tian XY, Wong WT, Leung FP, Yung LH, Chen ZY, Lau CW, Vanhoutte PM, Yao X, Huang Y
Journal
Eur J Nutr 52(3):1145-55
Abstract

PURPOSE: Postmenopausal women experience higher risks for cardiovascular diseases than age-matched men and pre-menopausal women. There is a need for better treatment strategy for estrogen-deficient-related cardiovascular complications. We and others have recently reported that activated renin-angiotensin system and the associated oxidative stress impaired endothelium-dependent relaxation in ovariectomized rat, while angiotensin receptor blocker rescues endothelial dysfunction. Dietary supplements and lifestyle modifications provide an alternative way to improve cardiovascular health. The present study tests the hypothesis that chronic cranberry juice consumption improves cholesterol profiles and vascular functions in estrogen-deficient animal model. The effect of cranberry consumption on expression and activity of renin-angiotensin system in the vasculature will be determined.
METHODS: Ovariectomized rats were treated daily with commercial cranberry juice at 7 mg/kg for 8 weeks, a dosage comparable to recent clinical studies. Serum was collected for measuring cholesterol levels while aorta was isolated for isometric force assay and expression studies.
RESULTS: Cranberry juice consumption reduced circulating levels of total cholesterol, triacylglycerols, HDL, nHDL, and nHDL/HDL ratio. Meanwhile, cranberry juice consumption improved endothelium-dependent relaxation in aorta of ovariectomized rats by restoring p-eNOS level (endothelial nitric oxide synthase phosphorylated at ser-1177), reversing the up-regulated levels of renin-angiotensin system markers (angiotensin-converting enzyme, angiotensin II, and angiotensin II type 1 receptor), and normalizing the elevated NAD(P)H oxidase expression and oxidative stress.
CONCLUSIONS: Our data demonstrate the novel cardiovascular benefits of cranberry juice consumption in improving both vascular functions and cholesterol profiles, providing insight into developing cranberry products into useful dietary supplements for postmenopausal women.

Cranberries and wild blueberries treated with gastrointestinal enzymes positively modify glutathione mechanisms in Caco-2 cells in vitro

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Authors
Slemmer JE, Livingston-Thomas JM, Gottschall-Pass KT, Sweeney MI
Journal
J Food Sci 78(6):H943-7
Abstract

Beneficial health effects of cranberries (CBs) and wild blueberries (BBs), such as reduced levels of oxidative stress, have been demonstrated in feeding studies. These Vaccinium berries contain high levels of flavonoids; however, the bioavailability of flavonoids is generally low. We investigated the in vitro effects of these berries on intestinal cells, focusing on mitigating oxidative stress and associated reactive oxygen species (ROS). First, we simulated the passage of CB and BB through the gastrointestinal (GI) tract by treating berry homogenates to a battery of digestive enzymes. Then, Caco-2 cells, a model of small intestine epithelial uptake, were exposed to these homogenates for 60 min. Using a cell-free assay, we found that the antioxidant activity in CB homogenates was not affected by these enzymes, but that BB homogenates treated with gut enzymes had 43% lower free-radical quenching activity (P 0.05). However, both of the enzyme-treated homogenates were still able to counteract the ROS-generating ability of H2O2 added exogenously to Caco-2 cells. Berry homogenates also increased mitochondrial metabolic rates at 60 min posttreatment, as measured by MTT assays. Enzyme-treated CB (but not BB) homogenates increased the levels of reduced glutathione (GSH) relative to oxidized glutathione (GSSG), a critical indicator of the cellular redox state (P 0.05). Our data suggest that CBs do not lose their antioxidant ability when passing through the GI tract, and specifically, digested CB may serve to enhance cytoprotective effects in intestinal cells by reducing potential damage caused by free radicals and ROS derived from other food sources

Cranberry extract suppresses interleukin-8 secretion from stomach cells stimulated by Helicobacter pylori in every clinically separated strain but inhibits growth in part of the strains

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Authors
Matsushima M, Suzuki T, Masui A, Mine T, Takagi A
Journal
J Funct Food 5(2):729–35
Abstract

It is known that cranberry inhibits the growth of Helicobacter pylori (HP). In human stomach, HP basically induces chronic inflammation by stimulating stomach cells to secrete interleukin (IL)-8 and other inflammatory cytokines, and causes stomach cancer, etc. The aim of this study was to investigate the inhibiting effects of cranberry on HP growth and IL-8 secretion from stomach cells induced by HP, using clinically separated HP strains. HP growth in liquid culture and on-plate culture was evaluated by titration after 2-day incubation and by agar dilution technique, respectively. For IL-8 experiments, MKN-45, a stomach cancer cell line, was incubated with HP for 24 h and IL-8 in the medium was assayed by ELISA. Cranberry suppressed growth of the bacteria only in six of the 27 strains. Meanwhile, it suppressed IL-8 secretion in all the strains. The results may suggest a possible role of cranberry in prevention of stomach cancer by reducing gastric inflammation.

Cranberry impairs selected behaviors essential for virulence in Proteus mirabilis HI4320

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Authors
McCall J, Hidalgo G, Asadishad B, Tufenkji N
Journal
Can J Microbiol 59(6):430-436
Abstract

Proteus mirabilis is an etiological agent of complicated urinary tract infections. North American cranberries (Vaccinium macrocarpon) have long been considered to have protective properties against urinary tract infections. This work reports the effects of cranberry powder (CP) on the motility of P. mirabilis HI4320 and its expression of flaA, flhD, and ureD. Our results show that swimming and swarming motilities and swarmer-cell differentiation were inhibited by CP. Additionally, transcription of the flagellin gene flaA and of flhD, the first gene of the flagellar master operon flhDC, decreased during exposure of P. mirabilis to various concentrations of CP. Moreover, using ureD-gfp, a fusion of the urease accessory gene ureD with gfp, we show that CP inhibits urease expression. Because we demonstrate that CP does not inhibit the growth of P. mirabilis, the observed effects are not attributable to toxicity. Taken together, our results demonstrate that CP hinders motility of P. mirabilis and reduces the expression of important virulence factors.

Cranberry Proanthocyanidins Improve Intestinal sIgA During Elemental Enteral Nutrition

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Authors
Pierre JF, Heneghan AF, Feliciano RP, Shanmuganayagam D, Krueger CG, Reed JD, Kudsk KA
Journal
JPEN J Parenter Enteral Nutr DOI: 10.1177/0148607112473654
Abstract

Background: Elemental enteral nutrition (EEN) decreases gut-associated lymphoid tissue (GALT) function, including fewer Peyer's patch lymphocytes and lower levels of the tissue T helper 2 (Th2) cytokines and mucosal transport protein polymeric immunoglobulin receptor (pIgR), leading to lower luminal secretory immunoglobulin A (sIgA) levels. Since we recently demonstrated that cranberry proanthocyanidins (PACs) maintain the Th2 cytokine interleukin (IL)-4 when added to EEN, we hypothesized the addition of PACs to EEN would normalize other GALT parameters and maintain luminal levels of sIgA. Methods: Institute of Cancer Research mice were randomized (12/group) to receive chow, EEN, or EEN + PACs (100 mg/kg body weight) for 5 days, starting 2 days after intragastric cannulation. Ileum tissue was collected to measure IL-4 by enzyme-linked immunosorbent assay, pIgR by Western blot, and phosphorylated STAT-6 by microarray. Intestinal wash fluid was collected to measure sIgA by Western blot. Results: Compared with chow, EEN significantly decreased tissue IL-4, phosphorylated STAT-6, and pIgR. The addition of PACs to EEN prevented these alterations. Compared with chow, EEN resulted in significantly lower levels of luminal sIgA. The addition of PACs to EEN increased luminal sIgA levels compared with EEN alone. Conclusions: This study suggests the addition of PACs to EEN may support GALT function and maintain intestinal sIgA levels compared with EEN administration alone.

Cranberry proanthocyanidins improve the gut mucous layer morphology and function in mice receiving elemental enteral nutrition

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Authors
Pierre JF, Heneghan AF, Feliciano RP, Shanmuganayagam D, Roenneburg DA, Krueger CG, Reed JD, Kudsk KA
Journal
JPEN-Parenter Enter 37(3):401-9
Abstract

BACKGROUND: Lamina propria Th2 cytokines, interleukin (IL)-4 and IL-13, stimulate goblet cell (GC) proliferation and MUC2 production, which protect the intestinal mucosa. Elemental enteral nutrition (EEN) reduces tissue IL-4 and impairs barrier function. Proanthocyanidins (PACs) stimulate oral mucin levels. We hypothesized that adding PAC to EEN would maintain Th2-without stimulating Th1-cytokines and preserve luminal MUC2 vs EEN alone. Materials and
METHODS: Seventy mice were randomized to 5 diet groups-standard chow, intragastric EEN, or EEN with lowPAC, midPAC (50 mg), or highPAC (100 mg PAC/kg BW)-for 5 days, starting 2 days after gastric cannulation. Ileal tissue was analyzed for histomorphology and the cytokines IL-4, IL-13, IL-1, IL-6, and TNF- by enzyme-linked immunosorbent assay. MUC2 was measured in intestinal washes.
RESULTS: EEN lowered IL-13 (P .05) compared with standard chow, whereas IL-4 was not significant (P .07). LowPAC and midPAC increased IL-13 (P .05), whereas highPAC increased both IL-4 and IL-13 (P .05) compared with EEN. All EEN diets reduced (P .05) crypt depth compared with the chow group. Compared with standard chow, GC numbers and luminal MUC2 were reduced with EEN (P .05). These effects were attenuated (P .05) with midPAC and highPAC. No changes were observed in tissue Th1 cytokines.
CONCLUSIONS: Adding PACs to EEN reverses impaired intestinal barrier function following EEN by improving the gut mucous layer and function through increased GC size and number as well as levels of MUC2 and ileal IL-4 and IL-13.

Effects of anthocyanins on the AhR-CYP1A1 signaling pathway in human hepatocytes and human cancer cell lines.

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Authors
Kamenickova A, Anzenbacherova E, Pavek P, Soshilov AA, Denison MS, Zapletalova M, Anzenbacher P, Dvorak Z
Journal
Toxicol Lett 221(1):1-8
Abstract

Anthocyanins are plant pigments occurring in flowers and berry fruits. Since a phenomenon of food-drug interactions is increasingly emerging, we examined the effects of 21 major anthocyanins and the extracts from 3 food supplements containing anthocyanins on the aryl hydrocarbon receptor (AhR)-cytochrome P450 CYP1A1 signaling pathway in human hepatocytes and human hepatic HepG2 and intestinal LS174T cancer cells. Pelargonidin-3-O-rutinoside (PEL-2) and cyanidin-3,5-O-diglucoside (CYA-3) dose-dependently activated AhR, as revealed by gene reporter assay. PEL-2 and CYA-3 induced CYP1A1 mRNA but not protein in HepG2 and LS174T cells. Neither compounds induced CYP1A1 mRNA and protein in four different primary human hepatocytes cultures. The effects of PEL-2 and CYA-3 on AhR occurred by ligand-dependent and ligand-independent mechanisms, respectively, as demonstrated by ligand binding assay. In a direct enzyme inhibition assay, none of the antocyanins tested inhibited the CYP1A1 marker activity to less than 50% even at 100 μM concentration. PEL-2 and CYA-3 at 100 μM inhibited CYP1A1 to 79% and 65%, respectively. In conclusion, with exception of PEL-2 and CYA-3, there were no effects of 19 major anthocyanins and 3 food supplements containing anthocyanins on AhR-CYP1A1 signaling, implying zero potential of these compounds for food-drug interactions with respect to AhR-CYP1A1 pathway.

Effects of cranberry components on human aggressive periodontitis gingival fibroblasts.

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Authors
Tipton DA, Babu JP, Dabbous MKh
Journal
J Periodontal Res 48(4):433-42
Abstract

BACKGROUND AND OBJECTIVE: Aggressive periodontitis (AgP) causes rapid periodontal breakdown involving AgP gingival fibroblast production of cytokines [i.e. interleukin (IL)-6, a bone metabolism regulator], and matrix metalloproteinase (MMP)-3. Lipopolysaccharide upregulates fibroblast IL-6 and MMP-3, via transcription factors (i.e. NF-kB). Cranberry (Vaccinium macrocarpon) inhibits lipopolysaccharide-stimulated macrophage and normal gingival fibroblast activities, but little is known of its effects on AgP fibroblasts. Objectives of this study are to use AgP fibroblasts, to determine cytotoxicity of cranberry components or periodontopathogen (Fusobacterium nucleatum, Porphyromonas gingivalis) lipopolysaccharide +/- cranberry components, and effects of cranberry components on lipopolysaccharide-stimulated NF-kB activation and IL-6 and MMP-3 production.
MATERIAL AND METHODS: AgP fibroblasts were incubated = 6 d with high molecular weight non-dialyzable material (NDM) (derived from cranberry juice (1-500 mug/mL) or lipopolysaccharide (1 mug/mL) +/- NDM. Membrane damage and viability were assessed by enzyme activity released into cell supernatants and activity of a mitochondrial enzyme, respectively. Secreted IL-6 and MMP-3 were measured by ELISA. NF-kB p65 was measured via binding to an oligonucleotide containing the NF-kB consensus site. Data were analyzed using analysis of variance and Scheffe's F procedure for post hoc comparisons.
RESULTS: Short-term exposure to NDM, or lipopolysaccharide +/- NDM caused no membrane damage. NDM (= 100 mug/mL) or lipopolysaccharide +/- NDM had no effect on viability = 7 d exposure. NDM (50 mug/mL) inhibited lipopolysaccharide-stimulated p65 (P = 0.003) and constitutive or lipopolysaccharide-stimulated MMP-3 (P = 0.02). NDM increased AgP fibroblast constitutive or lipopolysaccharide-stimulated IL-6 (P = 0.0001), but inhibited normal human gingival fibroblast IL-6 (P = 0.01).
CONCLUSION: Lack of toxicity of low NDM concentrations, and its inhibition of NF-kB and MMP-3, suggest that cranberry components may regulate AgP fibroblast inflammatory responses. Distinct effects of NDM on AgP and gingival fibroblast production of IL-6 (which can have both positive and negative effects on bone metabolism) may reflect phenotypic differences in IL-6 regulation in the two cell types.