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Urinary Tract Health and Antibacterial Benefits: In-Vitro

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A-type cranberry proanthocyanidins and uropathogenic bacterial anti-adhesion activity

Posted
Authors
Howell AB, Reed JD, Krueger CG, Winterbottom R, Cunningham DG, Leahy M
Journal
Phytochemistry 66(18):2281-91
Abstract

Clinical, epidemiological and mechanistic studies support the role of cranberry (Vaccinium macrocarpon Ait.) in maintaining urinary tract health. Cranberry proanthocyanidins contain A-type linkages and have been associated with preventing adhesion of P-fimbriated uropathogenic Escherichia coli to uroepithelial cells. It is not known if the presence of the A-type linkage is a prerequisite for anti-adhesion activity. Other commercial sources of proanthocyanidins with all B-type linkages have not previously been screened for this activity. The goals of this study were to compare the in vitro anti-adhesion activity of A-linked proanthocyanidins from cranberry juice cocktail with the anti-adhesion activities of B-linked proanthocyanidins from commercial grape and apple juices, green tea and dark chocolate, and determine if anti-adhesion activity is detectable in human urine following consumption of single servings of each commercial food product. Structural heterogeneity and presence of the A-type linkage in cranberry proanthocyanidins was confirmed utilizing MALDI-TOF/MS and DI/ESI MS, as was the presence of all B-type linkages in the proanthocyanidins from the other commercial products. The isolated A-type proanthocyanidins from cranberry juice cocktail elicited in vitro anti-adhesion activity at 60 microg/ml, the B-type proanthocyanidins from grape exhibited minor activity at 1200 microg/ml, while other B-type proanthocyanidins were not active. Anti-adhesion activity in human urine was detected following cranberry juice cocktail consumption, but not after consumption of the non-cranberry food products. Results suggest that presence of the A-type linkage in cranberry proanthocyanidins may enhance both in vitro and urinary bacterial anti-adhesion activities and aid in maintaining urinary tract health.

Cranberry products inhibit adherence of p-fimbriated Escherichia coli to primary cultured bladder and vaginal epithelial cells.

Posted
Authors
Gupta K, Chou MY, Howell A, Wobbe C, Grady R, Stapleton AE
Journal
J Urol 177(6):2357-60
Abstract

PURPOSE: Cranberry proanthocyanidins have been identified as possible inhibitors of Escherichia coli adherence to uroepithelial cells. However, little is known about the dose range of this effect. Furthermore, it has not been studied directly in the urogenital system. To address these issues we tested the effect of a cranberry powder and proanthocyanidin extract on adherence of a P-fimbriated uropathogenic E. coli isolate to 2 new urogenital model systems, namely primary cultured bladder epithelial cells and vaginal epithelial cells.

MATERIALS AND METHODS: E. coli IA2 was pre-incubated with a commercially available cranberry powder (9 mg proanthocyanidin per gm) or with increasing concentrations of proanthocyanidin extract. Adherence of E. coli IA2 to primary cultured bladder epithelial cells or vaginal epithelial cells was measured before and after exposure to these products.

RESULTS: Cranberry powder decreased mean adherence of E. coli IA2 to vaginal epithelial cells from 18.6 to 1.8 bacteria per cell (p 0.001). Mean adherence of E. coli to primary cultured bladder epithelial cells was decreased by exposure to 50 mug/ml proanthocyanidin extract from 6.9 to 1.6 bacteria per cell (p 0.001). Inhibition of adherence of E. coli by proanthocyanidin extract occurred in linear, dose dependent fashion over a proanthocyanidin concentration range of 75 to 5 mug/ml.

CONCLUSIONS: Cranberry products can inhibit E. coli adherence to biologically relevant model systems of primary cultured bladder and vaginal epithelial cells. This effect occurs in a dose dependent relationship. These findings provide further mechanistic evidence and biological plausibility for the role of cranberry products for preventing urinary tract infection.

Effects of cranberry juice on uropathogenic Escherichia coli in vitro biofilm formation

Posted
Authors
Di Martino P, Agniel R, Gaillard JL, Denys P
Journal
J Chemother 17(5):563-5
Abstract

No abstract

Influence of cranberry phenolics on glucan synthesis by glucosyltransferases and Streptococcus mutans acidogenicity

Posted
Authors
Gregoire S, Singh AP, Vorsa N, Koo H
Journal
J Appl Microbiol 103(5):1960-8
Abstract

"AIMS: To investigate the influence of several phenolic compounds isolated from cranberry fruit (Vaccinium macrocarpon) on some of the virulence properties of Streptococcus mutans associated with glucan synthesis and acidogenicity.

METHODS AND RESULTS: Individual phenolic acids, flavonols and proanthocyanidins were isolated by semi-preparative high-performance liquid chromatography from fresh cranberry fruit. Flavonols and proanthocyanidins (at 500 micromol l(-1)) moderately inhibited the activity of surface-adsorbed glucosyltransferases (GTFs) B and C and F-ATPases (15-35% inhibition; P 0.05), and also disrupted acid production by S. mutans cells without affecting bacterial viability. Phenolic acids displayed minimal biological effects. Quercetin-3-arabinofuranoside, myricetin and procyanidin A2 displayed the most inhibition of S. mutans virulence traits; a combination of these compounds displayed enhanced effects.

CONCLUSIONS: Specific flavonoids from cranberries exhibit statistically significant but moderate biological activity against S. mutans. The biological activity of cranberry extracts may be a result from the complex mixture of flavonoids rather than a single active compound.

SIGNIFICANCE AND IMPACT OF STUDY: This is the first study to identify the bioactive constituents in cranberry against an oral bacterium using highly purified isolated compounds. The combined effects of specific flavonols and proanthocyanidins from cranberry on GTFs activity, acid production and acid tolerance of S. mutans make them attractive compounds to fully explore for their anti-biofilm and cariostatic properties."

Prevention of nonspecific bacterial cell adhesion in immunoassays by use of cranberry juice.

Posted
Authors
Johnson-White B, Buquo L, Zeinali M, Ligler FS
Journal
Anal Chem 78(3):853-7
Abstract

The ability of Vaccinum macrocarpon, the North American cranberry, to prevent bacterial adhesion has been used to advantage in the prevention of urinary tract infections and has recently been described for the prevention of adhesion of bacteria responsible for oral infections and stomach ulcers. This report documents the ability of cranberry juice to reduce nonspecific adhesion of bacteria to the borosilicate glass microscope slides used in an immunoarray biosensor format. Nonspecific binding of analytes in the array sensor leads to high background signals that cause increased detection limits and false positives. Reduction in background-to-signal ratios can be seen as the juice concentration is increased from 0 to 50% of the sample. This impact cannot be duplicated with grape, orange, apple, or white cranberry juice. Sugar content and pH have been eliminated as the agents in the juice responsible for the anti-adhesive activity.

Antiviral effects on bacteriophages and rotavirus by cranberry juice.

Posted
Authors
Lipson SM, Sethi L, Cohen P, Gordon RE, Tan IP, Burdowski A, Stotzky G.
Journal
Phytomedicine 14(1):23-30
Abstract

Studies were undertaken to investigate the antiviral effects of comestible juices, especially cranberry juice, on non-related viral species. After exposure of bacteriophage T2 to a commercially available cranberry (Vaccinium macrocarpon) juice cocktail (CJ), virus infectivity titer was no longer detectible. After a 60-min exposure to orange (OJ) and grapefruit juices (GJ), phage infectivity was reduced to 25-35% of control, respectively. Similar data were observed for the bacteriophage T4. CJ inactivation of phage T4 was rapid, dose-dependent, and occurred at either 4 or 23 degrees C. Neither pH nor differences in sugar/carbohydrate levels among the juices may be ascribed to the recognized antiviral effects. Further studies were performed to identify the occurrence of antiviral activity by CJ to a mammalian enteric virus. The treatment of the simian rotavirus SA-11 with a 20% CJ suspension was sufficient to inhibit hemagglutination. Under scanning and transmission electron microscopy, CJ was observed to inhibit the adsorption of phage T4 to its bacterial host cells and prevented the replication of rotavirus in its monkey kidney (MA-104) host cells, respectively. The data suggest, for the first time, a non-specific antiviral effect towards unrelated viral species (viz., bacteriophages T2 and T4 and the simian rotavirus SA-11) by a commercially available cranberry fruit juice drink.

Impact of cranberry on Escherichia coli cellular surface characteristics

Posted
Authors
Johnson BJ, Lin B, Dinderman MA, Rubin RA, Malanoski AP, Ligler FS
Journal
Biochem Biophys Res Comm 377(3):992-4
Abstract

The anti-adhesive effects of cranberry have been attributed to both interactions of its components with the surface of bacterial cells and to inhibition of p-fimbriae expression. Previous reports also suggested that the presence of cranberry juice changed the Gram stain characteristics of Escherichia coli. Here, we show that the morphology of E. coli is changed when grown in the presence of juice or extract from Vaccinium macrocarpon (cranberry). Gene expression analysis indicates the down regulation of flagellar basal body rod and motor proteins. Consistent with this finding and previous reports, the SEM images indicate a decrease in the visible p-fimbriae. The iodine used in Gram-staining protocols was found to interact differently with the bacterial membrane when cells were cultured in spiked media. Slight alterations in the Gram stain protocol demonstrated that culturing in the presence of cranberry juice does not change the Gram stain characteristics contradicting other reports.

An examination of the anti-adherence activity of cranberry juice on urinary and nonurinary bacterial isolates

Posted
Authors
Schmidt DR, Sobota AE
Journal
Microbios 55(224-225):173-81
Abstract

In a previous investigation it was demonstrated that cranberry juice cocktail was able to inhibit adherence in 77 clinical isolates of Escherichia coli obtained from patients with diagnosed urinary tract infections. This work has been extended to include clinical isolates of E. coli, Proteus, Klebsiella, Enterobacter and Pseudomonas isolated from urine, sputum, wound and stool. Bacterial strains isolated from urine adhere in greater numbers to urinary tract epithelial cells than organisms isolated from sputum, stool and wound sources. E. coli, isolated from urine, adheres to urinary epithelial cells, in numbers three times greater than E. coli isolated from other clinical sources, and thus appears to represent a unique population of cells in terms of adherence. Cranberry juice cocktail and urine and urinary epithelial cells obtained after drinking the cocktail all demonstrate antiadherence activity against Gram-negative rods isolated from urine and other clinical sources. Drinking the cocktail may be useful in managing urinary tract infections in certain patients.

Cranberry changes the physicochemical surface properties of E. coli and adhesion with uroepithelial cells

Posted
Authors
Liu Y, Gallardo-Moreno AM, Pinzon-Arango PA, Reynolds Y, Rodriguez G, Camesano TA.
Journal
Colloids Surface B 65(1):35-42
Abstract

Cranberries have been suggested to decrease the attachment of bacteria to uroepithelial cells (UC), thus preventing urinary tract infections, although the mechanisms are not well understood. A thermodynamic approach was used to calculate the Gibbs free energy of adhesion changes (DeltaG(adh)) for bacteria-UC interactions, based on measuring contact angles with three probe liquids. Interfacial tensions and DeltaG(adh) values were calculated for Escherichia coli HB101pDC1 (P-fimbriated) and HB101 (non-fimbriated) exposed to cranberry juice (0-27 wt.%). HB101pDC1 can form strong bonds with the Gal-Gal disaccharide receptor on uroepithelial cells, while HB101-UC interactions are only non-specific. For HB101 interacting with UC, DeltaG(adh) was always negative, suggesting favorable adhesion, and the values were insensitive to cranberry juice concentration. For the HB101pDC1-UC system, DeltaG(adh) became positive at 27wt.% cranberry juice, suggesting that adhesion was unfavorable. Acid-base (AB) interactions dominated the interfacial tensions, compared to Lifshitz-van der Waals (LW) interactions. Exposure to cranberry juice increased the AB component of the interfacial tension of HB101pDC1. LW interactions were small and insensitive to cranberry juice concentration. The number of bacteria attached to UC was quantified in batch adhesion assays and quantitatively correlated with DeltaG(adh). Since the thermodynamic approach should not agree with the experimental results when specific interactions are present, such as HB101pDC-UC ligand-receptor bonds, our results may suggest that cranberry juice disrupts bacterial ligand-UC receptor binding. These results help form the mechanistic explanation of how cranberry products can be used to prevent bacterial attachment to host tissue, and may lead to the development of better therapies based on natural products.

Direct adhesion force measurements between E. coli and human uroepithelial cells in cranberry juice cocktail

Posted
Authors
Liu Y, Pinzón-Arango PA, Gallardo-Moreno AM, Camesano TA
Journal
Mol Nutr Food Res 54(12):1744-1752
Abstract

Scope: Atomic force microscopy (AFM) was used to directly measure the nanoscale adhesion forces between P-fimbriated Escherichia coli (E. coli) and human uroepithelial cells exposed to cranberry juice, in order to reveal the molecular mechanisms by which cranberry juice cocktail (CJC) affects bacterial adhesion.Methods and results: Bacterial cell probes were created by attaching P-fimbriated E. coli HB101pDC1 or non-fimbriated E. coli HB101 to AFM tips, and the cellular probes were used to directly measure the adhesion forces between E. coli and uroepithelial cells in solutions containing: 0, 2.5, 5, 10, and 27 wt% CJC. Macroscale attachment of E. coli to uroepithelial cells was measured and correlated to nanoscale adhesion force measurements. The adhesion forces between E. coli HB101pDC1 and uroepithelial cells were dose-dependent, and decreased from 9.32+/-2.37 nN in the absence of CJC to 0.75+/-0.19 nN in 27 wt% CJC. Adhesion forces between E. coli HB101 and uroepithelial cells were low in buffer (0.74+/-0.18 nN), and did not change significantly in CJC (0.78+/-0.18 nN in 27 wt% CJC; P=0.794).Conclusion: Our study shows that CJC significantly decreases nanoscale adhesion forces between P-fimbriated E. coli and uroepithelial cells.