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.

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.

Traditionally, cranberry has been used for the treatment and prophylaxis of urinary tract infections. Research suggests that its mechanism of action is preventing bacterial adherence to host cell surface membranes. Systematic reviews have concluded that no reliable evidence supports the use of cranberry in the treatment or prophylaxis of urinary tract infections; however, more recent, randomized controlled trials demonstrate evidence of cranberry's utility in urinary tract infection prophylaxis. Supporting studies in humans are lacking for other clinical uses of cranberry. Cranberry is a safe, well-tolerated herbal supplement that does not have significant drug interactions.

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.

The chemopreventive efficacy of cranberry juice concentrate in an experimental model of urinary bladder cancer was evaluated using female Fischer-344 rats. The animals received N-butyl-N-(4-hydroxybutyl)-nitrosamine (OH-BBN) for a period of eight weeks. Cranberry juice concentrate was administered at doses of 1.0 or 0.5 ml/rat/day beginning one week after the final OH-BBN treatment and continuing until the end of the study. The urinary bladders of all the rats were weighed and examined grossly for lesions, and all masses were submitted for pathological evaluation. A dose-dependent preventive effect of cranberry treatment was observed, with a reduced number of urinary bladder cancers (38%) in the 1.0 ml/rat/day group versus the control group. The cranberry extract neither affected body weight gain nor caused other signs of toxicity. For the metabolic studies, serum and urine were collected at 4 and 12 h after the administration of the cranberry juice concentrate and were analyzed by LC-MS/MS. Quercetin and its methylated derivative were detected in the urine samples. However, no quercetin was detected in the serum samples, indicating its poor bioavailability. These data suggest that components of cranberries may be effective in preventing urinary bladder carcinogenesis.

No abstract - Purpose: The aim of our correspondence is to submit the results of a small study (the first in a Greek population to our knowledge) about administering cranberries in the form of capsules to healthy postmenopausal women with recurrent UTIs.

OBJECTIVE: To determine the effectiveness of cranberry supplement at preventing urinary tract infections (UTIs) in persons with spinal cord injury (SCI).

DESIGN: A prospective, double-blinded, placebo-controlled, crossover study.

PARTICIPANTS: 21 individuals with neurogenic bladders secondary to SCI.

MAIN OUTCOME MEASURES: Favorable or unfavorable response of cranberry supplement vs placebo on urinary bacterial counts and white blood cell (WBC) counts and the combination of bacterial and WBC counts.

METHODS: Individuals with neurogenic bladders due to SCI were recruited and randomly assigned to standardized 400-mg cranberry tablets or placebo 3 times a day for 4 weeks. After 4 weeks and an additional 1-week ""washout period,"" participants were crossed over to the other group. Participants were seen weekly, during which a urine analysis was obtained. UTI was defined as significant bacterial or yeast colony counts in the urine and elevated WBC counts (WBC count > or = 10 per high power field) in centrifuged urine. Participants with symptomatic infections were treated with appropriate antibiotics for 7 days and restarted on the cranberry tablet/ placebo after a 7-day washout period. Urinary pH between the cranberry and placebo groups was compared weekly. Data were analyzed using the Ezzet and Whitehead's random effect approach.

RESULTS: There was no statistically significant treatment (favorable) effect for cranberry supplement beyond placebo when evaluating the 2 treatment groups for bacterial count, WBC count, or WBC and bacterial counts in combination. Urinary pH did not differ between the placebo and cranberry groups.

CONCLUSION: Cranberry tablets were not found to be effective at changing urinary pH or reducing bacterial counts, urinary WBC counts, or UTIs in individuals with neurogenic bladders. Further long-term studies evaluating specific types of bladder management and UTIs will help to determine whether there is any role for the use of cranberries in individuals with neurogenic bladders.

OBJECTIVE: To investigate the potential influence of cranberry juice on urinary biochemical and physicochemical risk factors associated with the formation of calcium oxalate kidney stones, as this product might affect the chemical composition of urine.

SUBJECTS AND METHODS: Urinary variables were assessed in a randomized cross-over trial in 20 South African men (students) with no previous history of kidney stones. The first group of 10 subjects drank 500 mL of cranberry juice diluted with 1500 mL tap water for 2 weeks, while the second group drank 2000 mL of tap water for the same period. This was followed by a 2-week 'washout' period before the two groups crossed over. During the experimental phase subjects kept a 3-day food diary to assess their dietary and fluid intakes; 24-h urine samples were collected at baseline and on day 14 of the trial periods, and analysed using modern laboratory techniques. Urine analysis data were used to calculate the relative urinary supersaturations of calcium oxalate, uric acid and calcium phosphate. Data were assessed statistically by analysis of variance.

RESULTS: The ingestion of cranberry juice significantly and uniquely altered three key urinary risk factors. Oxalate and phosphate excretion decreased while citrate excretion increased. In addition, there was a decrease in the relative supersaturation of calcium oxalate, which tended to be significantly lower than that induced by water alone.

CONCLUSION: Cranberry juice has antilithogenic properties and, as such, deserves consideration as a conservative therapeutic protocol in managing calcium oxalate urolithiasis.

Ulcer-associated dyspepsia is caused by infection with Helicobacter pylori. H. pylori is linked to a majority of peptic ulcers. Antibiotic treatment does not always inhibit or kill H. pylori with potential for antibiotic resistance. The objective of this study was to determine the potential for using phenolic phytochemical extracts to inhibit H. pylori in a laboratory medium. Our approach involved the development of a specific phenolic profile with optimization of different ratios of extract mixtures from oregano and cranberry. Subsequently, antimicrobial activity and antimicrobial-linked urease inhibition ability were evaluated. The results indicated that the antimicrobial activity was greater in extract mixtures than in individual extracts of each species. The results also indicate that the synergistic contribution of oregano and cranberry phenolics may be more important for inhibition than any species-specific phenolic concentration. Further, based on plate assay, the likely mode of action may be through urease inhibition and disruption of energy production by inhibition of proline dehydrogenase at the plasma membrane.

AIM: To study isolation and chemical characterization of pectin derived from the common cranberry Vaccinium oxycoccos L. (oxycoccusan OP) and the testing of its preventive effect on experimental colitis.

METHODS: Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid.

RESULTS: In the mice treated with OP, colonic macroscopic scores (1.1+/-0.4 vs 2.7, P0.01) and the total square area of damage (10+/-2 vs 21+/-7, P0.01) were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons (42+/-11 vs 112+/-40, P0.01) and enhance the amount of mucus of colitis mice (0.9+/-0.1 vs 0.4+/-0.1, P0.01). The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice (3.6+/-0.7 vs 5.1+/-0.8, P0.01). OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability (161+/-34 vs 241+/-21, P0.01). Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP (141+/-50 vs 235+/-37, P0.05).

CONCLUSION: Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.