Cranberry juice for prophylaxis of urinary tract infections – Conclusions from clinical experience and research

Cranberry juice (Vaccinium macrocarpon) is a widely used and recommended North-American folk remedy for prophylaxis of urinary tract infections (UTI). Clinical trials have documented its efficacy in women with recurrent UTI, but so far not in other groups of patients. The composition of effective cranberry products and its dosage in UTI prophylaxis have not been defined. Intriguing experimental research has identified an anti-adhesive mechanism of cranberry juice that prevents docking of bacteria on host tissues. This efficacy mechanism can be traced in patients’ urine following oral intake of cranberry products and appears to be due to proanthocyanidins with an A-type linkage of flavanols. The application of this anti-adhesion mechanism of cranberry-proanthocyandins is currently also investigated in other common diseases of bacterial pathogenesis, for example Helicobacter pylori-associated gastritis and dental caries/periodontal disease. The use of cranberry products appears to be safe and provide additional benefits by anti-oxidant and cholesterol-lowering activity.     

Urinary excretion of anthocyanins in humans after cranberry juice ingestion

Cranberry, which is rich in polyphenols, including anthocyanins and proanthocyanidins, has been found to have various effects beneficial to human health, including prevention of urinary tract infections. These effects have been associated with polyphenols in the fruit. We investigated the excretion of anthocyanins in human urine after ingestion of cranberry juice. Eleven healthy volunteers consumed 200 ml of cranberry juice containing 650.8 microg total anthocyanins. Urine samples were collected within 24 h before and after consumption. Six of 12 anthocyanins identified in cranberry were quantified in human urine by HPLC coupled with electrospray ionization and tandem mass spectrometry (HPLC-ESI-MS-MS). Among these, peonidin 3-O-galactoside, the second most plentiful anthocyanin in the juice, was found most abundantly in urine within 24 h, corresponding to 41.5 nmol (56.1% of total anthocyanins). The urinary levels of anthocyanins reached a maximum between 3 and 6 h after ingestion, and the recovery of total anthocyanins in the urine over 24 h was estimated to be 5.0% of the amount consumed. This study found high absorption and excretion of cranberry anthocyanins in human urine.     

The structure of cranberry proanthocyanidins which inhibit adherence of uropathogenic P-fimbriated Escherichia coli in vitro

Ethyl acetate extracts of Sephadex LH20-purified proanthocyanidins of American cranberry (Vaccinium macrocarpon Ait.) exhibited potent biological activity by inhibiting adherence of uropathogenic isolates of P-fimbriated Escherichia coli bacteria to cellular surfaces containing alpha-Gal(1-->4)beta-Gal receptor sequences similar to those on epithelial cells in the urinary tract. The chemical structures of the proanthocyanidins were determined by 13C NMR, electrospray mass spectrometry, matrix-assisted laser absorption time-of-flight mass spectrometry and by acid catalyzed degradation with phloroglucinol. The proanthocyanidin molecules consisted predominantly of epicatechin units with mainly DP of 4 and 5 containing at least one A-type linkage. The procyanidin A2 was the most common terminating unit occurring about four times as frequently as the epicatechin monomer.     

Position and orientation of gallated proanthocyanidins in lipid bilayer membranes: influence of polymerization degree and linkage type

It is well known that the biological activity of gallated proanthocyanidins (PAs) is highly structure-dependent. Polymerization degree (DP) and linkage types affect their biological activity greatly. Positions and orientations of gallated PAs in lipid bilayer reveal their structure-function activity at the molecular level. The present work aimed at determining the locations and orientations of epigallocatechin-3-gallate (EGCG) and its derivatives: A-type and B-type EGCG dimers and trimers in 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC) and 1-palmitoyl-2-oleoyl phosphatidylethanolamine (POPE) lipid bilayer via molecular dynamic (MD) simulations. The results showed that EGCG and its derivatives localized in the lipid bilayer or on the bilayer/water interface. Their penetration depths and orientations depended on both DP and linkage types. The penetration depths decreased with the increase of DP, sequencing to be EGCG > EGCG dimers > EGCG trimers. Spatially stretched A-type PAs could form more hydrogen bonds (H-bonds) with deep oxygen atoms of lipid bilayer and have higher affinity to the lipid bilayer than B-type PAs. Our results will provide an explicit evidence for PAs’ distinct biological activities.     

Dietary factors affecting the urinary mutagenicity assay system. II. The absence of mutagenic activity in human urine following consumption of red wine or grape juice

The mutagenic activity of urine samples from nonsmoking individuals before and after the consumption of either red wine or grape juice was determined. Urine samples collected from individuals on liquid or regular diets were concentrated using XAD-2 resin. No mutagenic activity of urine concentrates was detected with Salmonella tester strains TA98 or TA100 with or without microsomal activation. The addition of 1000 units of beta-glucuronidase into the agar overlay did not show any mutagenic activity. The mutagens in red wine and grape juice, however, were extracted using the XAD-2 column. Concentrates of urine samples spiked with either of the two extracts exhibited mutagenic activity.     

The antioxidative function, preventive action on disease and utilization of proanthocyanidins

Proanthocyanidins, which belong to a class of polyphenols, are widely distributed throughout the plant kingdom. Most people ingest trace amounts of proanthocyanidins through foods such as red wine and cranberry juice. However, the functional properties of proanthocyanidins have been little understood. Since 1983, we have studied the antioxidative functions, preventive actions on diseases and utilization of proanthocyanidins. The antioxidative activities of proanthocyanidins were found to be much stronger than vitamin C or vitamin E in aqueous systems. The mechanisms for their antioxidative actions were shown to involve radical scavenging, quenching, and enzyme-inhibiting actions. The preventive actions of proanthcyanidins on diseases relating to reactive oxygen species was examined using animal tests. Proanthocyanidin-rich grape seed extract was showed to have preventive actions on diseases such as atherosclerosis, gastric ulcer, large bowel cancer, cataracts and diabetes. In human intervention trials, grape seed extract was shown to have preventive effects on the increase in lipid peroxides in human plasma after exercise and on muscle fatigue after training. The uses and manufacturing techniques of proanthocyanidin products were subsequently developed. The products were launched as antioxidants in food additives, ingredients in nutritional supplements, and cosmetics.     

Bioavailability of anthocyanidin-3-glucosides following consumption of red wine and red grape juice

Pharmacokinetic parameters and the bioavailability of several dietary anthocyanins following consumption of red wine and red grape juice were compared in nine healthy volunteers. They were given a single oral dose of either 400 mL of red wine (279.6 mg total anthocyanins) or 400 mL of red grape juice (283.5 mg total anthocyanins). Within 7 h, the urinary excretion of total anthocyanins was 0.23 and 0.18% of the administered dose following red grape juice and red wine ingestion, respectively. Pharmacokinetic parameters derived from plasma and urine concentrations exhibited higher variability after ingestion of red grape juice. Compared to red grape juice anthocyanins, the relative bioavailability of red wine anthocyanins was calculated to be 65.7, 61.3, 61.9, 291.5, 57.1, and 76.3% for the glucosides of cyanidin, delphinidin, malvidin, peonidin, petunidin, and its sum (referred to as total anthocyanins), respectively. Bioequivalence was established for none of the anthocyanins. On a low level, urinary excretion of anthocyanins was fast, and the excretion rates seem to exhibit monoexponential characteristics over time after ingestion of both red grape juice and red wine. Due to low bioavailability, any significant contribution of anthocyanins to health protecting properties of red wine or red grape juice seems questionable, but the clinical relevance of these findings awaits further investigation.     

Effect of phytochemical concentrations on biological activities of cranberry extracts

Plants of cranberry (Vaccinium macrocarpon) furnish edible fruits and derivates that have been used for the prevention and treatment of urinary tract infections. In the present work we compare two commercial extracts that contain proanthocyanins (PACs) at 4 percent and 20 percent for antimicrobial, antiproliferative, antiradical and protective properties against oxidative stress on cell lines. Both extracts showed antimicrobial activity (MIC values range 3-100 microg/ml). Extract at 20 percent PACs showed higher antiproliferative activity against HepG2 and MCF7 cells, but not against C2C12 cells. Both extracts showed a dose-dependent free-radical scavenging capacity, and a protective effect on the cell damage was also revealed by reduction of intracellular active oxygen species release. Cranberry extracts confirmed antioxidative properties and efficacy in reduction of cell viability that resulted stronger against tumor cells. The pretreatment with cranberry extracts, furthermore, reveal an increase of cell resistance against oxidative stress, suggesting a potential role as a dietary supplement in preventing free-radical damage. The proanthocyanidin content is critical to determine the extract efficacy. In cellular experiments the extracts resulted clearly differentiated in their activity, and the activity was strongly influenced by PACs content. Only in DPPH test the free radical scavenging activity seemed to be directly related to proanthocyanidins content.     

Impact of cranberry on Escherichia coli cellular surface characteristics

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.     

In vitro inhibitory effect of cranberry (Vaccinium macrocarpom Ait.) juice on pathogenic microorganisms

The purpose of this study was to determine the inhibitory effects of cranberry juice on pathogenic microorganisms. The microorganisms analyzed were Escherichia coli from patients with urinary infections, Salmonella spp., Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus. The disc method was used to determine the sensitivity of bacteria to cranberry juice (CJ, both concentrated and diluted). A lawn of 10(6) cfu/ml was grown on agar surfaces in Petri dishes and on Whatman discs that had been previously saturated with CJ and CJ : water 1 : 1 to 1 : 50 juice solutions had been placed on the discs, which were cultured and incubated. The results indicated that S. aureus was more susceptible to cranberry juice inhibition than the other microorganisms. L. monocytogenes was the most resistant to the inhibitory action of cranberry juice, showing a significant difference from the inhibition of P. aeruginosa, uropathogenic E. coli, Salmonella spp., and S. aureus. This study also demonstrated that the inhibitory activity of cranberry juice for E. coli took place up to a dilution of 1 : 20.     

UHPLC-Q-Orbitrap-HRMS-based global metabolomics reveal metabolome modifications in plasma of young women after cranberry juice consumption

Plasma metabolome in young women following cranberry juice consumption were investigated using a global UHPLC-Q-Orbitrap-HRMS approach. Seventeen female college students, between 21 and 29 years old, were given either cranberry juice or apple juice for three days using a cross-over design. Plasma samples were collected before and after juice consumption. Plasma metabolomes were analyzed using UHPLC-Q-Orbitrap-HRMS followed by orthogonal partial least squares-discriminant analyses (OPLS-DA). S-plot was used to identify discriminant metabolites. Validated OPLS-DA analyses showed that the plasma metabolome in young women, including both exogenous and endogenous metabolites, were altered following cranberry juice consumption. Cranberry juice caused increases of exogenous metabolites including quinic acid, vanilloloside, catechol sulfate, 3,4-dihydroxyphenyl ethanol sulfate, coumaric acid sulfate, ferulic acid sulfate, 5-(trihydroxphenyl)-gamma-valerolactone, 3-(hydroxyphenyl)proponic acid, hydroxyphenylacetic acid and trihydroxybenzoic acid. In addition, the plasma levels of endogenous metabolites including citramalic acid, aconitic acid, hydroxyoctadecanoic acid, hippuric acid, 2-hydroxyhippuric acid, vanilloylglycine, 4-acetamido-2-aminobutanoic acid, dihydroxyquinoline, and glycerol 3-phosphate were increased in women following cranberry juice consumption. The metabolic differences and discriminant metabolites observed in this study may serve as biomarkers of cranberry juice consumption and explain its health promoting properties in human.     

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

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.     

Cranberry components for the therapy of infectious disease

Summary of the in vitro data support a beneficial effect of cranberry or its proanthocyanin constituents by blocking adhesion to and biofilm formation on target tissues of pathogens. In vivo data partially support these beneficial effects. Consumption of various cranberry products benefited young and elderly females in preventing urinary tract infections, and in conjunction with antibiotic treatment in eradicating Helicobacter pylori infections in women. Mouthwash supplemented with an isolated cranberry derivative reduced significantly the caryogenic mutans streptococci. None of the mice infected intranasal with lethal dose of influenza virus and treated with cranberry fraction died after two weeks. Further studies should focus on the active cranberry component as supplement for food and other products especially where whole juice or powder cannot be used.     

Characterisation of polyphenols by HPLC-PAD-ESI/MS and antioxidant activity in Equisetum telmateia

The antioxidant activity of an aqueous extract (infusion) and respective ethyl acetate fraction of Equisetum telmateia Ehrh. (Equisetaceae), a plant used in traditional medicine for its anti-inflammatory and diuretic properties, has been evaluated by DPPH, TEAC and TBARS assays. A high and significant antioxidant activity was detected in the ethyl acetate fraction. Analysis of the aqueous extract and the ethyl acetate fraction by HPLC-PAD-ESI/MS allowed the identification of the major phenolic compounds as flavan-3-ol, kaempferol and phenolic acid derivatives. Among the flavan-3-ols, A-type proanthocyanidins and afzelechin derivatives were detected as well as the more common B-type procyanidins, B2 and C1, whose identification was further confirmed by HPLC using detection involving chemical reaction with p-dimethylamino-cinnamaldehyde. The results suggest that the anti-inflammatory activity of E. telmateia could be due, at least in part, to the presence of compounds with antioxidant activity.     

Hypoglycemic activities of A- and B-type procyanidin oligomer-rich extracts from different Cinnamon barks

Procyanidin oligomers in Cinnamon are thought to be responsible for the biological activity in the treatment of diabetes mellitus (DM). To clarify types of procyanidin oligomers in different Cinnamon species and investigate their different effects, the present study investigated procyanidin oligomers in polyphenolic oligomer-rich extracts of three Cinnamon samples by LC-MS methods, and their hypoglycemic activities were detected in vivo and in vitro. The results showed that two of the three samples from Cinnamomum cassia were rich in B-type procyanidin oligomers, and the other sample was rich in A-type procyanidin oligomers. The Cinnamon extracts were administered at doses of 200 and 300 mg/kg body wt. in high-fat diet-fed and low-dose streptozotocin (STZ)-induced diabetic mice for 14 days. The results showed that blood glucose concentrations were significantly decreased in all Cinnamon extract groups compared with the control group (p < 0.05). Administration of the Cinnamon extracts significantly increased the consumption of extracellular glucose in insulin-resistant HepG2 cells and normal HepG2 cells compared with the control group. These results suggest that both A- and B-type procyanidin oligomers in different Cinnamon species have hypoglycemic activities and may improve insulin sensitivity in type 2 DM.     

<Emphasis Type="Italic">In vitro</Emphasis> inhibitory effect of cranberry (<Emphasis Type="Italic">Vaccinium macrocarpum</Emphasis> Ait.) juice on pathogenic microorganisms

The purpose of this study was to determine the inhibitory effects of cranberry juice on pathogenic microorganisms. The microorganisms analyzed were Escherichia coli from patients with urinary infections, Salmonella spp., Listeria monocytogenes, Pseudomona aeruginosa, and Staphylococcus aureus. The disc method was used to determine the sensitivity of bacteria to cranberry juice (CJ, both concentrated and diluted). A lawn of 10⁶ cfu/ml was grown on agar surfaces in Petri dishes and on Whatman discs that had been previously saturated with CJ and CJ : water. 1 : 1 to 1 : 50 juice solutions had been placed on the discs, which were cultured and incubated. The results indicated that S. aureus was more susceptible to cranberry juice inhibition than the other microorganisms. L. monocytogenes was the most resistant to the inhibitory action of cranberry juice, showing a significant difference from the inhibition of P. aeruginosa, uropathogenic E. coli, Salmonella spp., and S. aureus. This study also demonstrated that the inhibitory activity of cranberry juice for E. coli took place up to a dilution of 1 : 20. Published in Russian in Prikladnaya Biokhimiya i Mikrobiologiya, 2008, Vol. 44, No. 3, pp. 333–336. The text was submitted by the authors in English.     

Efficacy of cranberry juice on Helicobacter pylori infection: a double-blind, randomized placebo-controlled trial

BACKGROUND: Helicobacter pylori infection is a major cause of peptic ulcer disease and gastric cancer. This study postulated that cranberry juice would be effective in the suppression of H. pylori in an endemically infected population at high risk for gastric cancer. MATERIALS AND METHODS: A prospective, randomized, double-blind, placebo-controlled trial was conducted in Linqu County of Shandong Province, China, where 189 adults aged 48.9 +/- 11.2 years (mean +/- SD) with H. pylori infection were randomly divided into two groups: cranberry juice (n = 97) and placebo (n = 92). Participants were assigned to orally receive two 250-ml juice boxes of cranberry juice or matching placebo beverage daily for 90 days. The degree of H. pylori infection was determined using the 13C-urea breath test before randomization at 35 and 90 days of intervention to assess the efficacy of cranberry juice in alleviating infection. RESULTS: A total of 189 subjects with positive 13C-urea breath test results prior to randomization completed the study. At day 35 of intervention, 14 of the 97 (14.43%) from the the cranberry juice treatment group and 5 of the 92 (5.44%) of the placebo recipients had negative 13C-urea breath test results. After 90 days, the study concluded that 14 of the 97 subjects in the cranberry juice treatment group versus 5 of the 92 in the placebo group yielded negative test results. Eleven individuals from the cranberry juice treatment group and only two from the placebo group were negative at 35 and 90 days of experiment. These results are significant (p < .05). CONCLUSIONS: Regular consumption of cranberry juice can suppress H. pylori infection in endemically afflicted populations.     

Antiviral effects on bacteriophages and rotavirus by cranberry juice

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.     

A high molecular mass cranberry constituent reduces mutans streptococci level in saliva and inhibits in vitro adhesion to hydroxyapatite

Previous investigations showed that a high molecular mass, non-dialyzable material (NDM) from cranberries inhibits the adhesion of a number of bacterial species and prevents the co-aggregation of many oral bacterial pairs. In the present study we determined the effect of mouthwash supplemented with NDM on oral hygiene. Following 6 weeks of daily usage of cranberry-containing mouthwash by an experimental group (n = 29), we found that salivary mutans streptococci count as well as the total bacterial count were reduced significantly (ANOVA, P < 0.01) compared with those of the control (n = 30) using placebo mouthwash. No change in the plaque and gingival indices was observed. In vitro, the cranberry constituent inhibited the adhesion of Streptococcus sobrinus to saliva-coated hydroxyapatite. The data suggest that the ability to reduce mutans streptococci counts in vivo is due to the anti-adhesion activity of the cranberry constituent.