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2010

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Consumption of sweetened dried cranberries versus unsweetened raisins for inhibition of uropathogenic Escherichia coli adhesion in human urine: a pilot study

Posted
Authors
Greenberg JA, Newmann SJ and Howell AB
Journal
J Altern Complement Med 11(5):875-8
Abstract

OBJECTIVES: The aim of this study was to determine whether consumption of sweetened dried cranberries elicits urinary anti-adherence properties against Escherichia coli as previously demonstrated with cranberry juice and/or sweetened cranberry juice cocktail, compared to unsweetened raisins.

DESIGN: Uropathogenic E. coli isolates were obtained from five women with culture-confirmed urinary tract infections (UTIs). Four urine samples were collected from each subject. The first urine sample was collected before any study intervention. The second urine sample was collected 2-5 hours after consumption of one box (42.5 g) of raisins. The third urine sample was collected 5-7 days later. The final urine sample was collected 2-5 hours after consumption of approximately 42.5 g of dried cranberries.

MATERIALS AND METHODS: E. coli isolates were incubated separately in each of the four urine samples collected from the five subjects. Bacteria were harvested from the urine and tested for the ability to prevent adhesion of P-fimbriated E. coli bacteria using a mannose-resistant hemagglutination assay with human red blood cells (A1, Rh+).

RESULTS: Of the urine samples collected after dried cranberry consumption, one demonstrated 50% antiadherence activity, two demonstrated 25% activity, and two did not show any increased activity. None of the control urine samples and none of the postraisin consumption samples demonstrated any inhibitory activity.

CONCLUSIONS: Data from this pilot study on only five subjects suggest that consumption of a single serving of sweetened dried cranberries may elicit bacterial antiadhesion activity in human urine, whereas consumption of a single serving of raisins does not. Further studies are needed to verify the antiadhesion effect of sweetened dried cranberries. In addition, dose-response and pharmacokinetics of the active compounds in the dried cranberries need to be determined. If clinical research is positive, dried cranberries could potentially be a viable alternative to cranberry juice consumption for prevention of UTIs.

Cranberry or trimethoprim for the prevention of recurrent urinary tract infections? a randomized controlled trial in older women

Posted
Authors
McMurdo ME, Argo I, Phillips G, Daly F, Davey P
Journal
J Antimicrob Chemother 63(2):389-95
Abstract

OBJECTIVES: To compare the effectiveness of cranberry extract with low-dose trimethoprim in the prevention of recurrent urinary tract infections (UTIs) in older women.

PATIENTS AND METHODS: One hundred and thirty-seven women with two or more antibiotic-treated UTIs in the previous 12 months were randomized to receive either 500 mg of cranberry extract or 100 mg of trimethoprim for 6 months.

RESULTS: Thirty-nine of 137 participants (28%) had an antibiotic-treated UTI (25 in the cranberry group and 14 in the trimethoprim group); difference in proportions relative risk 1.616 (95% CI: 0.93, 2.79) P = 0.084. The time to first recurrence of UTI was not significantly different between the groups (P = 0.100). The median time to recurrence of UTI was 84.5 days for the cranberry group and 91 days for the trimethoprim group (U = 166, P = 0.479). There were 17/137 (12%) withdrawals from the study, 6/69 (9%) from the cranberry group and 11/68 (16%) from the trimethoprim group (P = 0.205), with a relative risk of withdrawal from the cranberry group of 0.54 (95% CI: 0.19, 1.37).

CONCLUSIONS: Trimethoprim had a very limited advantage over cranberry extract in the prevention of recurrent UTIs in older women and had more adverse effects. Our findings will allow older women with recurrent UTIs to weigh up with their clinicians the inherent attractions of a cheap, natural product like cranberry extract whose use does not carry the risk of antimicrobial resistance or super-infection with Clostridium difficile or fungi.

Dosage effect on uropathogenic escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study

Posted
Authors
Howell AB, Botto H, Combescure C, Blanc-Potard A-B, Gausa L, Matsumoto T, Tenke P, Sotto A, Lavigne JP
Journal
BMC Infect Dis 10:94
Abstract

BACKGROUND: Ingestion of cranberry (Vaccinium macrocarpon Ait.) has traditionally been utilized for prevention of urinary tract infections. The proanthocyanidins (PACs) in cranberry, in particular the A-type linkages have been implicated as important inhibitors of primarily P-fimbriated E. coli adhesion to uroepithelial cells. Additional experiments were required to investigate the persistence in urine samples over a broader time period, to determine the most effective dose per day and to determine if the urinary anti-adhesion effect following cranberry is detected within volunteers of different origins.

METHODS: Two separate bioassays (a mannose-resistant hemagglutination assay and an original new human T24 epithelial cell-line assay) have assessed the ex-vivo urinary bacterial anti-adhesion activity on urines samples collected from 32 volunteers from Japan, Hungary, Spain and France in a randomized, double-blind versus placebo study. An in vivo Caenorhabditis elegans model was used to evaluate the influence of cranberry regimen on the virulence of E. coli strain.

RESULTS: The results indicated a significant bacterial anti-adhesion activity in urine samples collected from volunteers that consumed cranberry powder compared to placebo (p 0.001). This inhibition was clearly dose-dependent, prolonged (until 24 h with 72 mg of PAC) and increasing with the amount of PAC equivalents consumed in each cranberry powder regimen. An in vivo Caenorhabditis elegans model showed that cranberry acted against bacterial virulence: E. coli strain presented a reduced ability to kill worms after a growth in urines samples of patients who took cranberry capsules. This effect is particularly important with the regimen of 72 mg of PAC.

CONCLUSIONS: Administration of PAC-standardized cranberry powder at dosages containing 72 mg of PAC per day may offer some protection against bacterial adhesion and virulence in the urinary tract. This effect may offer a nyctohemeral protection.

Interaction of flurbiprofen with cranberry juice, grape juice, tea, and fluconazole: in vitro and clinical studies

Posted
Authors
Greenblatt DJ, von Moltke LL, Perloff ES, Luo Y, Harmatz JS, Zinny MA
Journal
Clin Pharmacol Ther 79(1):125-33
Abstract

OBJECTIVES: Recent anecdotal, unvalidated case reports have suggested potentiation of warfarin-induced anticoagulation by cranberry juice, possibly through inhibition of human cytochrome P450 (CYP) 2C9, the enzyme responsible for the clearance of the active S-enantiomer of warfarin. To address this question, the effect of cranberry juice and other beverages on CYP2C9 activity was evaluated in vitro and in vivo.

METHODS: The effects of 4 beverages on CYP2C9 activity were studied in human liver microsomes, by use of flurbiprofen hydroxylation as the index reaction. In a clinical study 14 healthy volunteers received 100 mg flurbiprofen on 5 occasions in a crossover fashion, with at least 1 week separating the 5 trials. Flurbiprofen was preceded in random sequence by the following: (1) cranberry juice placebo (8 oz), (2) cranberry juice (8 oz), (3) brewed tea (8 oz), (4) grape juice (8 oz), and (5) fluconazole, a CYP2C9 inhibitor serving as a positive control, with 8 oz of water.

RESULTS: Flubiprofen hydroxylation in vitro was reduced to 11% +/- 8% of control by 2.5% (vol/vol) brewed tea, to 10% +/- 7% of control by grape juice, to 56% +/- 16% of control by cranberry juice, to 85% +/- 5% of control by cranberry juice placebo, and to 21% +/- 6% of control by the index inhibitor sulfaphenazole (2.5 micromol/L) (P .01 for all comparisons versus control). Flurbiprofen clearance (29-33 mL/min) and elimination half-life (3.3-3.4 hours) did not differ significantly among trials 1, 2, 3, and 4. However, clearance in the fluconazole treatment condition (trial 5) was significantly reduced compared with the placebo control (17 +/- 5 mL/min versus 31 +/- 8 mL/min, P .05), and the half-life was prolonged (5.3 +/- 1.6 hours versus 3.3 +/- 0.8 hours, P .05). Formation of 4-hydroxyflurbiprofen was correspondingly reduced by fluconazole (P .05).

CONCLUSIONS: Although grape juice and tea impaired CYP2C9 activity in vitro, none of the 3 beverages altered CYP2C9-mediated clearance of flurbiprofen in humans, making a pharmacokinetic interaction with warfarin highly unlikely.

Predictors of urinary tract infection after menopause: a prospective study

Posted
Authors
Jackson SL, Boyko EJ, Scholes D, Abraham L, Gupta K, Fihn SD
Journal
Am J Med 117(12):903-911
Abstract

Purpose: To describe the incidence of and risk factors for acute cystitis among nondiabetic and diabetic postmenopausal women.
Methods:We conducted a population-based, prospective cohort study of 1017 postmenopausal women, aged 55 to 75 years, who were enrolled in a health maintenance organization and followed for 2 years. A wide range of behavioral and physiologic exposures were assessed at baseline interview and follow-up clinic visits; the main outcome measure was microbiologically confirmed acute symptomatic cystitis. Follow-up was 87% at 12 months and 81% at 24 months.
Results:During 1773 person-years of follow-up, 138 symptomatic urinary tract infections occurred (incidence, 0.07 per person-year). Independent predictors of infection included insulin-treated diabetes (hazard ratio [HR] = 3.4; 95% confidence interval [CI]: 1.7 to 7.0) and a lifetime history of urinary tract infection (HR for six or more infections = 6.9; 95% CI: 3.5 to 13.6). Borderline associations included a history of vaginal estrogen cream use in the last month (HR = 1.8; 95% CI: 1.0 to 3.4), a history of kidney stones (HR = 1.9; 95% CI: 1.0 to 3.7), and asymptomatic bacteriuria at baseline (HR = 1.8; 95% CI: 0.9 to 3.5). Sexual activity, urinary incontinence, parity, postcoital urination, vaginal dryness, use of cranberry juice, vaginal bacterial flora, and postvoid residual bladder volume were not associated with incident acute cystitis after multivariable adjustment.
Conclusion:Insulin-treated diabetes is a potentially modifiable risk factor for incident acute cystitis among postmenopausal women, whereas a lifetime history of urinary tract infection was the strongest predictor. Use of oral or vaginal estrogen was not protective, and a wide range of behavioral and physiologic factors was not associated with acute cystitis episodes in this generally healthy sample.

The effect of cranberry juice and cranberry proanthocyanidins on the infectivity of human enteric viral surrogates.

Posted
Authors
Su X, Howell AB, D'Souza DH
Journal
Food Microbiol 27(4):535-40
Abstract

The effect of cranberry juice (CJ) and cranberry proanthocyanidins (PAC) on the infectivity of human enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), MS2(ssRNA) bacteriophage, and phiX-174(ssDNA) bacteriophage was studied. Viruses at high (approximately 7 log(10) PFU/ml) or low (approximately 5 log(10) PFU/ml) titers were mixed with equal volumes of CJ, 0.30, 0.60, and 1.20 mg/ml final PAC concentration, or water and incubated for 1 h at room temperature. Viral infectivity after treatments was evaluated using standardized plaque assays. At low viral titers, FCV-F9 was undetectable after exposure to CJ or the three tested PAC solutions. MNV-1 was reduced by 2.06 log(10) PFU/ml with CJ, and 2.63, 2.75, and 2.95 log(10) PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. MS2 titers were reduced by 1.14 log(10) PFU/ml with CJ, and 0.55, 0.80, and 0.96 log(10) PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. phi-X174 titers were reduced by 1.79 log(10) PFU/ml with CJ, and 1.95, 3.67, and 4.98 log(10) PFU/ml with PAC at 0.15, 0.30, and 0.60 mg/ml, respectively. Experiments using high titers showed similar trends but with decreased effects. CJ and PAC show promise as natural antivirals that could potentially be exploited for foodborne viral illness treatment and prevention.

A double-blinded, placebo-controlled, randomized trial of the neuropsychologic efficacy of cranberry juice in a sample of cognitively intact older adults: pilot study findings

Posted
Authors
Crews WD Jr, Harrison DW, Griffin ML, Addison K, Yount AM, Giovenco MA and Hazell J.
Journal
J Altern Complement Med 11(2):305-9
Abstract

OBJECTIVES: The aim of this research was to conduct the first known clinical trial of the short-term (i.e., 6 weeks) efficacy of cranberry juice on the neuropsychologic functioning of cognitively intact older adults.PARTICIPANTS: Fifty (50) community-dwelling, cognitively intact volunteers, > or = 60 years old, who reported no history of dementia or significant neurocognitive impairments, participated in this study.DESIGN: A 6-week, double-blind, placebo-controlled, randomized, parallel-group, clinical trial was utilized. Participants were randomly assigned to receive either 32 ounces/day of a beverage containing 27% cranberry juice per volume (n = 25) or placebo (n = 25) for 6 weeks, and administered a series of neuropsychologic tests at both pretreatment baseline and again after 6 weeks of either cranberry juice or placebo treatment to assess treatment-related changes.OUTCOME MEASURES: Efficacy measures consisted of participants' raw scores on the following standardized neuropsychologic tests: Selective Reminding Test, Wechsler Memory Scale-III Faces I and Faces II subtests, Trail Making Test (Parts A and B), Stroop Color and Word Test, and the Wechsler Adult Intelligence Scale- III Digit Symbol-Coding subtest. A subjective Follow-up Self-report Questionnaire was also administered to participants at the conclusion of the end-of-treatment phase assessments.RESULTS: Two-factor, mixed analyses of variance (ANOVA) revealed no significant group (cranberry juice and placebo) by trial (pretreatment baseline and end-of-treatment assessments) interactions across all of the neuropsychologic tests and measures utilized in this study when a Bonferroni corrected alpha level was used to correct for multiple comparisons (i.e., .05/17 group by trial comparisons = .003). Pearson Chi-Square analyses of the groups' self-reported changes over the 6-week treatment phase in their abilities to remember, thinking processes, moods, energy levels, and overall health on the Follow-up Self-report Questionnaire revealed no significant relationships. However, a nonsignificant trend (X2(1) = 2.373, p = 0.123) was noted for participants' self-reported overall abilities to remember from pretreatment baseline to the end-of-treatment assessment. Specifically, more than twice as many participants in the cranberry group (n = 9, 37.5%) rated their overall abilities to remember by treatment end as "improved" as compared to placebo controls (n = 4, 17.4%).CONCLUSIONS: Taken together, no significant interactions were found between the cranberry and placebo groups and their pretreatment baseline and end-of-treatment phase (after 6 weeks) standardized neuropsychologic assessments. A nonsignificant trend was noted, however, on a subjective, self-report questionnaire where twice as many participants in the cranberry group rated their overall abilities to remember by treatment end as "improved" compared to placebo controls.

Comparison of urinary cytokines after ingestion of cranberry juice cocktail in pregnant subjects: a pilot study.

Posted
Authors
Wing DA, Rumney PJ, Leu SY, Zaldivar F
Journal
Am J Perinatol 27(2):137-42
Abstract

Our objective was to evaluate urinary cytokine excretion after daily cranberry or placebo exposure in pregnant women. Four-hour urine samples were collected from 27 pregnant women subjects who were randomized to cranberry juice cocktail or placebo in three treatment arms: A: Cranberry (C) two times daily (C, C; n = 10 pregnant); B: cranberry in the AM, then placebo (P) in the PM (C, P; n = 9 pregnant); and C: placebo two times daily (P, P; n = 8 pregnant). Urinary cytokines were measured using commercially available kits. There was a statistically significant difference in interleukin (IL)-6 of the urinary cytokines between the multiple daily cranberry dosing group (group A [C, C]): median, 3.16 (range, 0.01 to 7.34) and the placebo group (group C [P, P]): 9.32 (0.53 to 29.61 pg/mL; p = 0.038, Kruskal-Wallis test). We concluded that a difference in IL-6 was found in the multiple daily cranberry dosing groups compared with placebo. Lack of differences based on treatment allocation in the other cytokines may be due to beta error. Further studies are planned to evaluate these assays for the assessment of clinical effect.

Cranberry juice and adhesion of antibiotic-resistant uropathogens

Posted
Authors
Howell AB and Foxman B
Journal
JAMA 287(23):3082-3
Abstract

No abstract - Introduction: Urinary tract infections (UTIs) account for more than 11 million physician visits annually in the United States and have become increasingly resistant to first-line antibiotic therapy. Recent evidence suggests that consumption of cranberry juice beverages is effective at preventing UTIs, although further studies are needed to validate potential treatment effects. While early research focused on a mechanism of urinary acidification, the largest clinical trial to date found no evidence to support this. Recent studies suggest that cranberry proanthocyanidins (condensed tannins) may inhibit P-fimbriated Escherichia coli from adhering to uroepithelial cells, the initial step in development of UTI. The effectiveness of cranberry proanthocyanidins and cranberry beverages against antibiotic-resistant E coli, however, has not been previously tested. We assessed whether consumption of cranberry juice cocktail prevents adhesion of antibiotic-resistant uropathogenic P-fimbriated E coli to the uroepithelium.

Cranberry juice and bacterial colonization in children--a placebo-controlled randomized trial

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Authors
Kontiokari T, Salo J, Eerola E and Uhari M
Journal
Clin Nutr 24(6):1065-72
Abstract

BACKGROUND: The cranberry produces antimicrobial compounds such as proanthocyanidines in response to microbial invasion. In vitro it is able to prevent growth, adhesion or biofilm formation of a large number of bacteria, while clinically, cranberry juice has been shown to prevent urinary tract infections (UTI) in women. However, the effect of cranberry on bacterial colonization more widely has not been evaluated. We were interested in studying cranberry juice in children since many children with recurrent UTI need long-term antimicrobial prophylaxis and would benefit from an alternative.

OBJECTIVE: To evaluate the effect of cranberry juice on nasopharyngeal and colonic bacterial flora, to evaluate how well cranberry juice is accepted by children and to evaluate its effect on infectious diseases and related symptoms.

DESIGN: Children (mean age 4.3 years) in day care centers were randomized to receive either cranberry juice (n=171) or a placebo (n=170) for 3 months. Bacterial samples were collected before and after the intervention and analyzed for both respiratory bacterial pathogens and enteric fatty acid composition, reflecting changes in the colonic bacterial flora. Infectious diseases and their symptoms were monitored using symptom diaries. Compliance was evaluated as the number of drop-outs during the trial and by counting the numbers of doses taken.

RESULTS: The carriage of respiratory bacteria did not change significantly during the intervention, while fecal fatty acid composition changed significantly with time (P0.001) but did not differ between the groups (P>0.05). Cranberry juice had no effect on common infectious diseases or their symptoms. The cranberry juice was well accepted: the number of drop-outs in 3 months was 18 (11%) in the cranberry group and 11 (7%) in the placebo group, and most of the doses were taken as instructed, 145 (88%) and 129 (77%) children, respectively, taking at least 90% of the doses.

CONCLUSIONS: Cranberry juice was well accepted by the children, but led to no change in either the bacterial flora in the nasopharynx or the bacterial fatty acid composition of stools. Thus cranberries seem to have beneficial effect on urinary health only and this is not compromised by other unexpected antimicrobial effects.