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2010

Displaying 11 - 20 of 217

Can cranberry supplementation benefit adults with type 2 diabetes?

Posted
Authors
Chambers BK, Camire ME
Journal
Diabetes Care 26(9):2695-6
Abstract

"Adults controlling their type 2 diabetes through diet alone were recruited from the Bangor, Maine, community. Fourteen subjects (aged 57.9 [+ or -] 10.6 years, 6 women, 8 men, duration of diabetes 6.0 [+ or -] 8.5 years) were randomized to the cranberry group; 13 subjects (aged 52.6 [+ or -] 13.7 years, 6 women, 7 men, duration of diabetes 4.1 [+ or -] 4.9 years) were assigned to the placebo group. Subjects consumed six capsules filled with either cranberry juice concentrate powder or a placebo daily for 12 weeks. Six capsules were equivalent to a 240-ml serving of cranberry juice cocktail. The artificially colored placebo mimicked the cranberry powder in all respects but flavonoid content. Subjects were asked to discontinue use of dietary supplements, but no other diet and lifestyle changes were made during the study.

More than one-half of the subjects had good control of blood glucose levels (7.0 mmol/l) at the beginning of the study. No differences were found between the treatment groups in fasting serum glucose, Hb[A.sub.1c], fructosamine, triglyceride, or HDL or LDL levels after 6 and 12 weeks. Placebo subjects had higher insulin values throughout the study (160 [+ or -] 167 vs. 86 [+ or -] 51 pmol/l at week 12, P 0.05). Different effects might be seen in subjects with poor glucose control, individuals with type 1 diabetes, or people who use medications to control their type 2 diabetes. "

Cranberry constituents affect fructosyltransferase expression in Streptococcus mutans

Posted
Authors
Feldman M, Weiss E, Shemesh M, Ofek I, Bachrach G, Rozen R, Steinberg D
Journal
Alternative Ther Health Med 15(2):32-8
Abstract

CONTEXT: Cranberry juice has long been recognized in folk medicine as a therapeutic agent, mainly in urinary tract infections. Its proposed mechanism of action is antiadhesion of bacteria.

OBJECTIVE: Investigation of the potential antiadhesion effect of nondialyzed material of cranberry (NDM) via its influence on secretion, gene expression, and promoter activity of the fructosyltransferase (FTF), which is among the extracellular enzymes associated with dental biofilm formation and pathogenesis of oral bacteria.

MAIN OUTCOME MEASURES: Secretion of FTF from Streptococcus mutans, in the presence of NDM, was measured by immunoblotting and confocal scanning laser microscopy. Its influence on ftf gene expression was determined by reverse transcription followed by real-time RT-PCR. The luciferase assay was used to detect bioluminescence expressed by the ftf promoter activity of bacteria exposed to NDM.

RESULTS: NDM at concentrations between 0.2/mL and 1mg/mL significantly (P.05) decreased secretion of extracellular FTF, as well as down-regulated ftf expression in a dose-dependent manner. NDM also markedly reduced the luciferase activity under the ftf promoter.

Interference of cranberry constituents in cell-cell signaling system of Vibrio harveyi

Posted
Authors
Feldman M, Weiss EI, Ofek I, Steinberg D
Journal
Curr Microbiol 59(4):469-74
Abstract

Cranberry juice has long been recognized in folk medicine as a therapeutic agent, mainly in urinary track infections. It acts as an antibiofilm agent against various pathogens. Quorum sensing is process where bacteria communicate with each other via signal molecules known as autoinducers. This process is strongly involved in various bacterial pathological and physiological pathways. Various strains of Vibrio harveyi bacteria were incubated with different concentrations of nondialyzable material of cranberry (NDM) with or without addition of exogenous autoinducer. Bioluminescence regulated by the autoinducers was measured in GENios reader. Effect of NDM alone or NDM supplemented with autoinducer on quorum sensing was determined as change in bioluminescence in each treated sample compared to appropriate control in every strain. Using model of V. harveyi, we found an inhibitory effect of cranberry constituents on bacterial signaling system. This effect was reversible, since exogenous autoinducer was able to recover bioluminescence which was decreased by NDM. We hypothesized that cranberry NDM interacts with V. harveyi quorum sensing by competition with autoinducer

Antioxidant levels of common fruits, vegetables, and juices versus protective activity against in vitro ischemia/reperfusion.

Posted
Authors
Bean H, Schuler C, Leggett RE and Levin RM
Journal
Int Urol Nephrol 42(2):409-15
Abstract

It is well known that antioxidants present in various fruits, vegetables, and juices have the potential to protect the urinary bladder from free radical damage. What is not well understood, however, is how well antioxidant activities detected by chemical methods such as the CUPRAC assay for total antioxidant activity (TAA) predict the level of physiological protection available. It is hypothesized that the level of antioxidant reactivity found by the CUPRAC assay will positively correlate with increased protection in a model of in vitro ischemia/reperfusion. To test this hypothesis, the CUPRAC assay was utilized to determine the antioxidant reactivity of a series of fruits, vegetables, and juices, and the results were compared to the protective ability of selected juices in an established in vitro rabbit bladder model of ischemia/reperfusion. The results of the CUPRAC test showed that cranberry juice had the highest level of antioxidant reactivity, blueberry juice had an intermediate activity, and orange juice had the lowest. It was determined, however, that contrary to the hypothesis, the orange juice was significantly more potent in protecting the bladder against ischemia/reperfusion damage than either blueberry or cranberry juice. Thus, it is concluded that chemical tests for TAA do not necessarily correlate with their physiological activity.

Loss of fimbrial adhesion with the addition of Vaccinum macrocarpon to the growth medium of P-fimbriated Escherichia coli

Posted
Authors
Ahuja S, Kaack B, Roberts J.
Journal
J Urol 159(2):559-62
Abstract

PURPOSE: Vaccinium macrocarpon--the American cranberry--irreversibly inhibits the expression of P-fimbriae of E. coli. Further effects on the function and expression of P-fimbriae were studied by growing P-fimbriated E. coli in solid media laced with cranberry juice.

METHODS: Cranberry concentrate at pH 7.0 was added to CFA medium to a final concentration of 25%. E. coli strains JR1 and DS17 were plated on this medium with a plain CFA control and incubated at 37C. Cultures were tested for ability to agglutinate P-receptor specific beads. Bacteria were washed in PBS and agglutination retested. Cultures were also replated on plain CFA agar and rechecked for their ability to agglutinate. Transmission electron micrographs were performed on positive control and test bacteria.

RESULTS: For E. coli strain JR1, P-fimbrial agglutination was inhibited after the third plating. DS17 was fully inhibited after the second plating. Washing in PBS did not affect agglutination, but replating on CFA agar allowed agglutination to recur. Electron micrographic study of control populations confirmed fimbriae. Fully inhibited bacteria had a 100% reduction in expression of fimbriae. Additionally, inhibited bacteria showed cellular elongation.

CONCLUSIONS: Cranberry juice irreversibly inhibits P-fimbriae. Electron micrographic evidence suggests that cranberry juice acts on the cell wall preventing proper attachment of the fimbrial subunits or as a genetic control preventing the expression of normal fimbrial subunits or both.

A high molecular mass constituent of cranberry juice inhibits helicobacter pylori adhesion to human gastric mucus.

Posted
Authors
Burger O, Ofek I, Tabak M, Weiss EI, Sharon N, Neeman I
Journal
FEMS Immunol Med Microbiol 29(4):295-301
Abstract

Because previous studies have shown that a high molecular mass constituent of cranberry juice inhibited adhesion of Escherichia coli to epithelial cells and coaggregation of oral bacteria, we have examined its effect on the adhesion of Helicobacter pylori to immobilized human mucus and to erythrocytes. We employed three strains of H. pylori all of which bound to the mucus and agglutinated human erythrocytes via a sialic acid-specific adhesin. The results showed that a high molecular mass constituent derived from cranberry juice inhibits the sialic acid-specific adhesion of H. pylori to human gastric mucus and to human erythrocytes.

Composition of a chemopreventive proanthocyanidin-rich fraction from cranberry fruits responsible for the inhibition of 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced ornithine decarboxylase (ODC) activity.

Posted
Authors
Kandil FE, Smith MA, Rogers RB, Pépin MF, Song LL, Pezzuto JM, Seigler DS
Journal
J Agric Food Chem 50(5):1063-9
Abstract

Phenolics from the American cranberry (Vaccinium macrocarpon) were fractionated into a series of proanthocyanidins and other flavonoid compounds by vacuum chromatography on a hydrophilic, porous polyvinylic gel permeation polymer. Antioxidant activity was not restricted to a particular class of components in the extract but was found in a wide range of the fractions. Significant chemopreventive activity, as indicated by an ornithine decarboxylase assay, was localized in one particular proanthocyanidin-rich fraction from the initial fractionation procedure. Further fractionation of the active anticarcinogenic fraction revealed the following components: seven flavonoids, mainly quercetin, myricetin, the corresponding 3-O-glycosides, (-)-epicatechin, (+)-catechin, and dimers of both gallocatechin and epigallocatechin types, and a series of oligomeric proanthocyanidins.

Cranberry juice and urinary-tract health: science supports folklore

Posted
Authors
Henig YS, Leahy MM
Journal
Nutrition 16(7-8):684-7
Abstract

In the 20th century, the health benefit most often attributed to the cranberry is its role in maintaining urinary-tract health. A 1998 study by the International Food Information Council (personal communication) indicated that 47% of consumers surveyed were aware of a link between cranberry juice and urinary-tract health.

Cranberry PACs and triterpenoids: anti-cancer activities in colon tumor cell lines

Posted
Authors
Liberty AM, Amoroso JW, Neto CC, Hart PE, Patil B, Murano P, Amiot-Carlin MJ
Journal
Acta Hort 841:61-66
Abstract

Phytochemicals from North American cranberry (Vaccinium macrocarpon) fruit may be expected to influence the development of colon cancer. Tissue-culture models were used to assess effects of cranberry components on cell proliferation, apoptosis, and the formation of tumor cell colonies. Several phytochemicals and fractions isolated from whole cranberry fruit were previously reported to inhibit growth and proliferation of breast, colon, prostate, and other tumor cell lines. In HT-29 and HCT116 colon tumor cell lines, cranberry proanthocyanidins (PACs) and ursolic acid inhibited the formation of tumor colonies over a two week period in a dose-dependent manner. Apoptosis is likely to play a role in limiting tumor cell proliferation. In HT-29 and HCT116 colon tumor cell lines treated with either ursolic acid or a cranberry proanthocyanidin fraction, the percentage of cells undergoing apoptosis increased in a dose-dependent manner. Thus, cranberry phytochemicals have the potential to limit carcinogenesis.

Effect of cranberry juice on urinary pH

Posted
Authors
Kinney AB, Blount M.
Journal
Nurs Res 28(5):287-90
Abstract

Twenty-one female and 19 male subjects who had normal physical and laboratory examinations were randomly assigned into four groups of 10 subjects each. Each group was then randomly assigned a number (150, 180, 210, 240) which determined the amount of cranberry juice, in milliliters, members of that group would ingest with each meal during the experimental phase of the study. The study took place over a 12-day period. A one-group before-and-after design was used, with each subject serving as his or her own control. Diet was controlled; menus on days 1 through 6 were repeated on days 7 through 12 with the addition of cranberry juice at each meal. Subjects used nitrazine pH tape to measure the pH of midstream urine at each voiding. There were significant (.01 level) differences in mean urinary pH between each control group and its corresponding experimental group. Anticipated problems with increased number of bowel movements, weight gain, increased voiding frequency, and subject pH measurement inaccuracy did not occur.