Anti-microbial Activity of Urine after Ingestion of Cranberry: A Pilot Study

Natural Products in the Treatment of Lower Urinary Tract Dysfunction and Infection

The popularity of natural products for the treatment of lower urinary tract symptoms (LUTS) differs considerably between countries. Here we discuss the clinical evidence for efficacy in two indications, male LUTS suggestive of benign prostatic hyperplasia and urinary tract infections, and the mechanistic evidence from experimental studies. Most evidence for male LUTS is based on extracts from saw palmetto berries, stinging nettle roots, and pumpkin seeds, whereas most evidence for urinary tract infection is available for European golden rod and combined preparations although this field appears more fragmented with regard to extract sources. Based on differences in sample collection and extraction, extracts from the same plants are likely to exhibit at least quantitative differences in potential active ingredients, which makes extrapolation of findings with one extract to those of others potentially difficult. While only limited information is available for most individual extracts, some extracts have been compared to placebo and/or active controls in adequately powered trials.

Natural therapeutics for urinary tract infections-a review

Background

The recurrence of the urinary tract infections (UTI), following the antibiotic treatments suggests the pathogen’s resistance to conventional antibiotics. This calls for the exploration of an alternative therapy.

Main body

The anti-uropathogenic and bactericidal activity of many plant extracts was reported by many researchers, which involves only preliminary antibacterial studies using different basic techniques like disk diffusion, agar well diffusion, or minimum inhibitory concentration (MIC) of the crude plant extracts, but reports on the specific action of the phytoconstituents against uropathogens are limited. Vaccinium macrocarpon Aiton (cranberry) is the best-studied home remedy for UTI. Some evidences suggest that proanthocyanins present in cranberry, prevent bacteria from adhering to the walls of the urinary tract, subsequently blocking the further steps of uropathogenesis. Probiotics such as Lactobacillus and Bifidobacterium are beneficial microorganisms that may act by the competitive exclusion principle to defend against infections in the urogenital tracts. Reports on potential vaccine agents and antibodies targeting the different toxins and effecter proteins are still obscure except uropathogenic E. coli.

Conclusion

This review highlights some of the medicinal herbs used by aborigines to prevent or treat acute or chronic urinary tract infections, botanicals with established urobactericidal activity, clinical trials undertaken to compare the efficacy of cranberry products in UTI prevention, and other natural therapeutics reported for UTI.

The risk of urinary tract infection in vegetarians and non-vegetarians: a prospective study

Urinary tract infection (UTI) is caused principally by ascending Escherichia coli infection via an intestine-stool-urethra route. Recent studies found that the strains of E. coli causing UTIs, called extra-intestinal pathogenic E. coli (ExPEC), were distinct from the intestinal pathogenic strains and normal commensal strains. Further analysis found the meat including poultry and pork is the major reservoir for ExPECs. Vegetarians avoid meat and should theoretically have less exposure to ExPEC. However, no study thus far has examined whether vegetarian diets reduce the risk of UTI. Our aim was to examine the association between vegetarian diet and UTI risk in a Taiwanese Buddhist population. We prospectively followed 9724 Buddhists free of UTI from 2005 to 2014. During the 10-year follow-up, 661 incident UTI cases were confirmed. Diet was assessed through a food frequency questionnaire. Cox regression was used to evaluate the prospective association between a vegetarian diet on risk of UTI while adjusting for age, sex, educational level, alcohol-drinking, smoking, hypertension, diabetes mellitus, hyperlipidemia, and disease conditions predisposing to UTIs. Overall, vegetarian diet was associated with 16% lower hazards (hazard ratio [HR]: 0.84, 95% confidence interval [CI]: 0.71-0.99). In subgroup analysis, the protective association between vegetarian diet and UTI is observed mainly in the female (HR: 0.82, 95% CI: 0.69-0.99), never smokers (HR: 0.80, 95% CI: 0.67-0.95), and for uncomplicated UTI (HR: 0.81, 95% CI: 0.68-0.98).

Effect of oral cranberry extract (standardized proanthocyanidin-A) in patients with recurrent UTI by pathogenic E. coli: a randomized placebo-controlled clinical research study

PURPOSE

To evaluate the effect of cranberry extract (PAC-A ~ proanthocyanidin-A) on the in vitro bacterial properties of uropathogenic (E. coli) and its efficacy/tolerability in patients with subclinical or uncomplicated recurrent UTI (r-UTI).

MATERIALS AND METHODS

After obtaining clearance from the ethics committee and administering a written informed consent, 72 patients with r-UTI were enrolled as per protocol (November 2011 to March 2013) in this prospective study, to randomly receive (PAC-A: group I, 36) or (placebo: group II, 36), for 12 weeks. Any change/reduction in the incidence of r-UTI at 12 weeks was construed to be the primary endpoint of this study.

RESULTS

After 12 weeks, bacterial adhesion scoring decreased (0.28)/(2.14) in group I/II (p < 0.001); 32/36 (88.8 %) and 2/36 (5.5 %) in groups I and II, respectively, turned MRHA negative (p < 0.001); biofilm (p < 0.01) and bacterial growth (p < 0.001) decreased in group I; microscopic pyuria score was 0.36/2.0 in group I/II (p < 0.001); r-UTI decreased to 33.33 versus 88.89 % in group I/II (p < 0.001); mean subjective dysuria score was 0.19 versus 1.47 in group I/II (p < 0.001), while mean urine pH was 5.88 versus 6.30 in group I/II (p < 0.001). No in vitro antibacterial activity of cranberry could be demonstrated, and no adverse events were noted.

CONCLUSIONS

The overall efficacy and tolerability of standardized cranberry extract containing (PAC-A) as a food supplement were superior to placebo in terms of reduced bacterial adhesion; bacterial MRHA negativity; urine pH reduction; and in preventing r-UTI (dysuria, bacteriuria and pyuria). Larger randomized controlled trials are needed to elucidate the precise role, exact dose and optimal duration of PAC-A therapy in patients at risk of r-UTI.

Herbal products in pregnancy: experimental studies and clinical reports

The aim of this work is to provide an update from an overview of the literature of the most frequently consumed herbal remedies during pregnancy, both alone and concomitantly with prescribed medications and particularly on their side effects to the mother and fetus. We have also analyzed some of the adverse interactions that may occur due to concomitant use of herbal and pharmaceutical products during pregnancy. Herbal remedies are not evaluated according to the same standards as pharmaceuticals, and in the USA some of it are not licensed but sold as food supplements. There is a lack of basic knowledge on the part of both clinicians and patients as to the indications for use and safety of herbal medicines used in pregnancy and lactation. If 'traditional use' is the only available information, the pregnant woman should be made aware of this to enable her to make an informed decision concerning potential use.

Cranberry-derived proanthocyanidins prevent formation of Candida albicans biofilms in artificial urine through biofilm- and adherence-specific mechanisms

OBJECTIVES

Candida albicans is a common cause of nosocomial urinary tract infections (UTIs) and is responsible for increased morbidity and healthcare costs. Moreover, the US Centers for Medicare & Medicaid Services no longer reimburse for hospital-acquired catheter-associated UTIs. Thus, development of specific approaches for the prevention of Candida urinary infections is needed. Cranberry juice-derived proanthocyanidins (PACs) have efficacy in the prevention of bacterial UTIs, partially due to anti-adherence properties, but there are limited data on their use for the prevention and/or treatment of Candida UTIs. Therefore, we sought to systematically assess the in vitro effect of cranberry-derived PACs on C. albicans biofilm formation in artificial urine.

METHODS

C. albicans biofilms in artificial urine were coincubated with cranberry PACs at serially increasing concentrations and biofilm metabolic activity was assessed using the XTT assay in static microplate and silicone disc models.

RESULTS

Cranberry PAC concentrations of ≥16 mg/L significantly reduced biofilm formation in all C. albicans strains tested, with a paradoxical effect observed at high concentrations in two clinical isolates. Further, cranberry PACs were additive in combination with traditional antifungals. Cranberry PACs reduced C. albicans adherence to both polystyrene and silicone. Supplementation of the medium with iron reduced the efficacy of cranberry PACs against biofilms.

CONCLUSIONS

These findings indicate that cranberry PACs have excellent in vitro activity against C. albicans biofilm formation in artificial urine. We present preliminary evidence that cranberry PAC activity against C. albicans biofilm formation is due to anti-adherence properties and/or iron chelation.

Stable binding of alternative protein-enriched food matrices with concentrated cranberry bioflavonoids for functional food applications

Defatted soy flour (DSF), soy protein isolate (SPI), hemp protein isolate (HPI), medium-roast peanut flour (MPF), and pea protein isolate (PPI) stably bind and concentrate cranberry (CB) polyphenols, creating protein/polyphenol-enriched matrices. Proanthocyanidins (PAC) in the enriched matrices ranged from 20.75 mg/g (CB-HPI) to 10.68 mg/g (CB-SPI). Anthocyanins (ANC) ranged from 3.19 mg/g (CB-DSF) to 1.68 mg/g (CB-SPI), whereas total phenolics (TP) ranged from 37.61 mg/g (CB-HPI) to 21.29 mg/g (CB-SPI). LC-MS indicated that the enriched matrices contained all identifiable ANC, PAC, and flavonols present in CB juice. Complexation with SPI stabilized and preserved the integrity of the CB polyphenolic components for at least 15 weeks at 37 °C. PAC isolated from enriched matrices demonstrated comparable antiadhesion bioactivity to PAC isolated directly from CB juice (MIC 0.4-0.16 mg/mL), indicating their potential utility for maintenance of urinary tract health. Approximately 1.0 g of polyphenol-enriched matrix delivered the same amount of PAC available in 1 cup (300 mL) of commercial CB juice cocktail, which has been shown clinically to be the prophylactic dose for reducing recurring urinary tract infections. CB-SPI inhibited Gram-positive and Gram-negative bacterial growth. Nutritional and sensory analyses indicated that the targeted CB-matrix combinations have high potential for incorporation in functional food formulations.

Cranberries and lower urinary tract infection prevention

Lower urinary tract infections are very common diseases. Recurrent urinary tract infections remain challenging to treat because the main treatment option is long-term antibiotic prophylaxis; however, this poses a risk for the emergence of bacterial resistance. Some options to avoid this risk are available, including the use of cranberry products. This article reviews the key methods in using cranberries as a preventive measure for lower urinary tract infections, including in vitro studies and clinical trials.

Biofilm formation and virulence of uropathogenic Escherichia coli in urine after consumption of cranberry-lingonberry juice

Cranberry-lingonberry juice (CLJ) was effective in preventing urinary tract infections (UTIs) in our earlier randomized clinical trial. We aimed to test whether consumption of CLJ at a similar dose to earlier reduces the biofilm formation and virulence of uropathogenic Escherichia coli in urine. Twenty healthy women drank 100 ml of CLJ daily for two weeks. Urine samples were obtained 2-4 hours after the last dose. Control samples were taken after a one-week period without berry consumption. Biofilm formation of 20 E. coli strains was measured at 72 hours by the polystyrene microtitre plate method. Quantitative real-time PCR analyses were performed for selected genes. Four of the 20 clinical strains produced more biofilm in urine after CLJ consumption (P < 0.05) and one produced less. Expression levels of the pga, cpxA, fimA and papF genes did not differ between bacteria grown in control urine and urine obtained after CLJ consumption, except for pga gene expression, which was reduced in one strain after CLJ (P = 0.04). It appears that the effect of CLJ in preventing UTIs is not explained by mechanisms that reduce biofilm formation or the expression of selected virulence genes of Escherichia coli in urine.