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Berry phenolics selectively inhibit the growth of intestinal pathogens

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Authors
Puupponen-Pimiä R, Nohynek L, Hartmann-Schmidlin S, Kähkönen M, Heinonen M, Määttä-Riihinen K, Oksman-Caldentey KM.
Journal
J Appl Microbiol 98(4):991-1000
Abstract

AIMS: To investigate the effects of berries and berry phenolics on pathogenic intestinal bacteria and to identify single phenolic compounds being responsible for antimicrobial activity.

METHODS AND RESULTS: Antimicrobial activity of eight Nordic berries and their phenolic extracts and purified phenolic fractions were measured against eight selected human pathogens. Pathogenic bacterial strains, both Gram-positive and Gram-negative, were selectively inhibited by bioactive berry compounds. Cloudberry and raspberry were the best inhibitors, and Staphylococcus and Salmonella the most sensitive bacteria. Phenolic compounds, especially ellagitannins, were strong inhibitory compounds against Staphylococcus bacteria. Salmonella bacteria were only partly inhibited by the berry phenolics, and most of the inhibition seemed to originate from other compounds, such as organic acids. Listeria strains were not affected by berry compounds, with the exception of cranberry. Phenolic compounds affect the bacteria in different mechanisms.

CONCLUSIONS: Berries and their phenolics selectively inhibit the growth of human pathogenic bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY: Antimicrobial properties of berries could be utilized in functional foods. Furthermore these compounds would be of high interest for further evaluation of their properties as natural antimicrobial agents for food and pharmaceutical industry

Changes in plasma antioxidant capacity and oxidized low-density lipoprotein levels in men after short-term cranberry juice consumption.

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Authors
Ruel G, Pomerleau S, Couture P, Lamarche B, Couillard C
Journal
Metabolism 54(7):856-61
Abstract

Low-density lipoprotein (LDL) oxidation is closely implicated in the development of atherosclerotic cardiovascular disease (CVD), and thus, reducing LDL susceptibility to oxidation with antoxidants could be of importance in CVD prevention. Flavonoids, polyphenolic compounds found in a large selection of fruits and vegetables, have been characterized as having a strong antioxidant potential, and intake of flavonoid-rich foods has been related to decreased morbidity and mortality from heart disease. The present study was therefore undertaken to investigate the effect of flavonoid-rich cranberry juice supplementation on plasma lipoprotein levels and LDL oxidation. For that purpose, 21 men (age +/- SD, 38 +/- 8 years) were enrolled in a 14-day intervention and instructed to drink cranberry juice 7 mL/kg body weight per day. Physical and metabolic measures including plasma lipid and oxidized LDL (OxLDL) concentrations as well as antioxidant capacity were performed before and after the intervention. At baseline, we found that plasma OxLDL levels were significantly associated with waist circumference ( r = 0.47, P = .0296) as well as plasma triglyceride ( r = 0.68, P = .0007) and apolipoprotein B ( r = 0.91, P .0001) concentrations. The intervention led to a reduction in plasma OxLDL levels (-9.9% +/- 17.8%, P = .0131) and increase in antioxidant capacity (+6.5% +/- 10.3%, P = .0140). However, no relationship was found between both of these changes ( r = -.01, not significant). The intervention did not result in any improvement of plasma lipoprotein-lipid or inflammatory marker concentrations. Our results show that short-term cranberry juice supplementation is associated with significant increase in plasma antioxidant capacity and reduction in circulating OxLDL concentrations. Although the physiological relevance of our observations needs to be further examined, our study supports the potential role of antioxidant-rich foods in maintaining health and preventing CVD.

Cranberry flavonoids, atherosclerosis and cardiovascular health

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Authors
Reed J
Journal
Crit Rev Food Sci Nutr 42(3 Suppl):301-16
Abstract

Atherosclerosis is the deposition of plaques containing cholesterol and lipids in arterial walls. Atherosclerosis causes cardiovascular disease that lead to heart attacks and stroke. Mortality from these diseases is the leading cause of death in the U.S. Atherogenisis starts with the uptake of oxidized LDL by endothelial macrophages, the accumulation of foam cells in the intima of the artery and the formation of fatty streaks. Research indicates that consumption of flavonoids in foods and beverages may decrease the risk of atherosclerosis. In vitro and in vivo experiments with flavonoids demonstrate that flavonoids are dietary antioxidants and inhibit LDL oxidation, inhibit platelet aggregation and adhesion, inhibit enzymes involved in lipid and lipoprotein metabolism that affect the immune response to oxidized LDL and their uptake by endothelial macrophages, may induce endothelium-dependent vassorelaxation, and may increase reverse cholesterol transport and decrease total and LDL cholesterol. Cranberries contain both hydroxycinnamic acids and flavonoids. The cranberry flavonoids belong to three groups: anthocyanins, flavonols, and proanthocyanidins. This article reviews the literature on the effects of flavonoids on atherosclerosis with an emphasis on the potential effects of the flavonols and proanthocyanidins in cranberries.

Cranberry juice and urinary tract infection.

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Authors
Raz R, Chazan B, Dan M
Journal
Clin Infect Dis 38(10):1413-9
Abstract

Cranberries have long been the focus of interest for their beneficial effects in preventing urinary tract infections (UTIs). Cranberries contain 2 compounds with antiadherence properties that prevent fimbriated Escherichia coli from adhering to uroepithelial cells in the urinary tract. Approximately 1 dozen clinical trials have been performed testing the effects of cranberries on the urinary tract. However, these trials suffer from a number of limitations. Most importantly, the trials have used a wide variety of cranberry products, such as cranberry juice concentrate, cranberry juice cocktail, and cranberry capsules, and they have used different dosing regimens. Further research is required to clarify unanswered questions regarding the role of cranberries in protecting against UTI in general and in women with anatomical abnormalities in particular.

Effect of high-dose cranberry juice on the pharmacodynamics of warfarin in patients

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Authors
Mellen CK, Ford M, Rindone JP
Journal
Br J Clin Pharmacol 70(1):139-42
Abstract

SUBJECT: Case reports suggest an association between cranberry juice and potentiation of warfarin. Studies using 240 ml of cranberry juice daily demonstrated no interaction. It is unknown if higher amounts of cranberry juice will interact with warfarin.

WHAT THIS STUDY ADDS: Cranberry juice at 240 ml twice daily does not alter the pharmacodynamics of warfarin.

AIM: To determine if high-dose cranberry juice (240 ml twice daily) alters the pharmacodynamic action of warfarin.

METHODS: Ten male patients taking stable doses of warfarin were given cranberry juice at 240 ml twice daily for 7 days. Prothrombin times were drawn at baseline and days 2, 6 and 8 after administration of the juice. Prothrombin times were averaged for each day and mean times were compared from each study day to baseline using repeated measures ANOVA.

RESULTS: There was no statistical difference between mean prothrombin time at baseline and any day tested during juice administration.

CONCLUSIONS: Cranberry juice (240 ml twice daily for 1 week) did not alter the pharmacodynamics of warfarin in patients.

Evidences of the cardioprotective potential of fruits: the case of cranberries.

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Authors
Ruel G, Couillard C
Journal
Mol Nutr Food Res 51(6):692-701
Abstract

Eating a healthy balanced diet, is one of the most important and relevant ways to delay and prevent various health complications including cardiovascular disease (CVD). Among the nutritional factors that have been investigated in recent years, dietary fat intake may be the one that has been most targeted. However, there is also clear epidemiological evidence that increased fruits and vegetables intake can significantly reduce the risk of CVD, an effect that has been suggested to be resulting to a significant extent, from the high polyphenol content of these foods. Numerous polyphenolic compounds such as flavonoids have been identified as having strong antioxidant properties. Most interesting is the fact that, in addition to being one of the largest groups of antioxidant phytochemicals, flavonoids are also an integral part of the human diet as they are found in most fruits and vegetables. Cranberries are one of the most important sources of flavonoids that have a strong antioxidant and anti-inflammatory capacities. Thus, consumption of cranberries or their related products could be of importance not only in the maintenance of health but also in preventing CVD. The following review will present evidences supported for the most part by clinical observations that cranberries can exert potentially healthy effects for your heart.

Favourable impact of low-calorie cranberry juice consumption on plasma HDL-cholesterol concentrations in men

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Authors
Ruel G, Pomerleau S, Couture P, Lemieux S, Lamarche B, Couillard C
Journal
Br J Nutr 96(2):357-64
Abstract

A low HDL-cholesterol concentration is an independent risk factor for CVD. Studies have suggested that flavonoid consumption may be cardioprotective, and a favourable impact on circulating HDL-cholesterol concentrations has been suggested to partially explain this association. The aim of the present study was to determine the effect of consuming increasing daily doses of low-calorie cranberry juice cocktail (CJC) on the plasma lipid profile of abdominally obese men. For that purpose, thirty men (mean age 51 (SD 10) years) consumed increasing doses of CJC during three successive periods of 4 weeks (125 ml/d, 250 ml/d, 500 ml/d). Before the study and after each phase, we measured changes in physical and metabolic variables. We noted a significant increase in plasma HDL-cholesterol concentration after the consumption of 250 ml CJC/d (+8.6+/-14.0% v. 0 ml CJC/d; P0.01), an effect that plateaued during the last phase of the study (500 ml CJC/d: +8.1+/-10.0% v. 0 ml CJC/d; P0.0001). Multivariate analyses revealed that changes in plasma apo A-I (R(2)=48%, P0.0001) and triacylglycerol (R(2)=16%, P0.005) concentrations were the only variables significantly contributing to the variation in plasma HDL-cholesterol concentration noted in response to the intervention. No variation was observed in total as well as in LDL and VLDL cholesterol. The present results show that daily CJC consumption is associated with an increase in plasma HDL-cholesterol concentrations in abdominally obese men. We hypothesise that polyphenolic compounds from cranberries may be responsible for this effect, supporting the notion that the consumption of flavonoid-rich foods can be cardioprotective.

Fighting infectious diseases with inhibitors of microbial adhesion to host tissues

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Authors
Sharon N, Ofek I
Journal
Crit Rev Food Sci Nutr 42(3 Suppl):267-72
Abstract

The majority of infectious diseases are initiated by the adhesion of pathogenic organisms to the tissues of the host. In many cases this adhesion is mediated by lectins present on the surface of the infectious organism that bind to complementary carbohydrates on the surface of the host tissues. Soluble carbohydrates recognized by the bacterial lectins block the adhesion of the bacteria to animal cells in vitro. Moreover, such carbohydrates have been shown to protect against experimental infection by lectin-carrying bacteria of different mammals, such as mice, rabbits, calves, and monkeys. Agents other than carbohydrates also block adhesion, as demonstrated with cranberry juice as well as with low and high molecular weight preparations isolated from the juice. Both kinds of preparation inhibited the adhesion in vitro of Escherichia coli to different animal cells. In addition, the high molecular weight material acted similarly on the adhesion of Helicobacter pylori to human gasrointenstinal cells, and on the coaggregation of oral bacteria. Furthermore, in limited clinical studies regular drinking of cranberry juice had a significant preventive effect on bacteriuria, and the high molecular weight constituent of the juices was also effective in decreasing the salivary level of Streptococus mutans, the major cause of tooth decay. Because the inhibitors of adhesion examined are not bactericidal, the selection of resistant inhibitor strains is unlikely to occur. Together, these findings may lead to new therapeutic strategies that are in dire need because of the world-wide increase in antibiotic resistant bacteria.

Low-calorie cranberry juice supplementation reduces plasma oxidized LDL and cell adhesion molecule concentrations in men.

Posted
Authors
Ruel G, Pomerleau S, Couture P, Lemieux S, Lamarche B, Couillard C
Journal
Br J Nutr 99(2):352-9
Abstract

Elevated circulating concentrations of oxidized LDL (OxLDL) and cell adhesion molecules are considered to be relevant markers of oxidative stress and endothelial activation which are implicated in the development of CVD. On the other hand, it has been suggested that dietary flavonoid consumption may be cardioprotective through possible favourable impacts on LDL particle oxidation and endothelial activation. The present study was undertaken to determine the effect of the daily consumption of low-calorie cranberry juice cocktail on plasma OxLDL, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin concentrations in men. Thirty men (mean age 51 (sd 10) years) were recruited and asked to consume increasing daily doses of cranberry juice cocktail (125, 250 and 500 ml/d) over three successive periods of 4 weeks. Plasma OxLDL and adhesion molecule concentrations were measured by ELISA before and after each phase. We noted a significant decrease in plasma OxLDL concentrations following the intervention (P 0.0001). We also found that plasma ICAM-1 (P 0.0001) and VCAM-1 (P 0.05) concentrations decreased significantly during the course of the study. In summary, the present results show that daily cranberry juice cocktail consumption is associated with decreases in plasma OxLDL, ICAM-1 and VCAM-1 concentrations in men.

Susceptibility of Helicobacter pylori isolates to the antiadhesion activity of a high-molecular-weight constituent of cranberry

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Authors
Shmuely H, Burger O, Neeman I, Yahav J, Samra Z, Niv Y, Sharon N, Weiss E, Athamna A, Tabak M, Ofek I
Journal
Diagn Microbiol Infect Dis 50(4):231-5
Abstract

The sensitivity of a large number of antibiotic-resistant and nonresistant Helicobacter pylori isolates to the antiadhesion effect of a high-molecular-mass, nondialysable constituent of cranberry juice was tested. Confluent monolayers of gastric cell line in microtiter plate wells were exposed to bacterial suspensions prepared from 83 H. pylori isolates from antibiotic-treated and untreated patients in the presence and absence of the cranberry constituent. Urease assay was used to calculate the percentage of adhesion inhibition. In two thirds of the isolates, adhesion to the gastric cells was inhibited by 0.2 mg/mL of the nondialysable material. There was no relationship between the antiadhesion effect of the cranberry material and metronidazole resistance in isolates from either treated or untreated patients (N=35). Only 13 isolates (16%) were resistant to both the nondialysable material and metronidazole, and 30 (36%) were resistant to the nondialysable material alone. There was no cross-resistance to the nondialysable material and metronidazole. These data suggest that a combination of antibiotics and a cranberry preparation may improve H. pylori eradication.