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Urinary Tract Health and Antibacterial Benefits: In-Vitro

Displaying 11 - 20 of 111

Inhibition of Pseudomonas aeruginosa PAO1 adhesion to and invasion of A549 lung epithelial cells by natural extracts.

Posted: 
April 1, 2015
Authors: 
Ahmed GF, Elkhatib WF, Noreddin AM
Journal: 
J Infect Public Health 7(5):436-44.
Abstract: 

Pseudomonas aeruginosa colonizes the lungs in cystic fibrosis (CF) and mechanically ventilated patients by binding to the cellular receptors on the surface of the lung epithelium. Studies have shown that blocking this interaction could be achieved with sub-minimum inhibitory concentrations of antibiotics such as ciprofloxacin. The development of bacterial resistance is a probable drawback of such an intervention. The use of natural extracts to interfere with bacterial adhesion and invasion has recently gained substantial attention and is
hypothesized to inhibit bacterial binding and consequently prevent or reduce pathogenicity. This study used an A549 lung epithelial cell infection model, and the results revealed that a combination of aqueous cranberry extract with ciprofloxacin could completely prevent the adhesion and invasion of P. aeruginosa PAO1 compared to the untreated control. All of the natural extracts (cranberry, dextran, and soybean extracts) and ciprofloxacin showed a significant reduction (P cells relative to the control. The cranberry, dextran, and soybean extracts could substantially increase the anti-adhesion and anti-invasion effects of ciprofloxacin to the averages of 100% (P (P as potential anti-adhesion and anti-invasion remedies, could be valuable in preventing or reducing P. aeruginosa lung infections.

Microbial catabolism of procyanidins by human gut microbiota.

Posted: 
April 1, 2015
Authors: 
Ou K, Sarnoski P, Schneider KR, Song K, Khoo C, Gu L
Journal: 
Mol Nutr Food Res 58(11):2196-205.
Abstract: 

SCOPE: A major portion of ingested procyanidins is degraded by human microbiota in the colon into various phenolic compounds. These microbial metabolites are thought to contribute to the health benefits of procyanidins in vivo. The
objective of this study was to identify and quantify the microbial metabolites of procyanidins after anaerobic fermentation with human microbiota.
METHODS AND RESULTS: (-)-Epicatechin, (+)-catechin, procyanidin B2, procyanidin A2, partially purified apple and cranberry procyanidins were incubated with human
microbiota at a concentration equivalent to 0.5 mM epicatechin. GC-MS analysis showed that common metabolites of all six substrates were benzoic acid, 2-phenylacetic acid, 3-phenylpropionic acid, 2-(3'-hydroxyphenyl)acetic acid,
2-(4'-hydroxyphenyl)acetic acid, 3-(3'-hydroxyphenyl)propionic acid, and hydroxyphenylvaleric acid. 5-(3',4'-Dihydroxyphenyl)-γ-valerolactones and 5-(3'-hydroxyphenyl)-γ-valerolactones were identified as the microbial metabolites of epicatechin, catechin, procyanidin B2, and apple procyanidins but not from the procyanidin A2 or cranberry procyanidin ferments. 2-(3',4'-Dihydroxyphenyl)acetic acid was only found in the fermented broth of procyanidin B2, A2, apple, and cranberry procyanidins. The mass recoveries of microbial metabolites range from 20.0 to 56.9% for the six substrates after 24 h
of fermentation.
CONCLUSION: Procyanidins, both B-type and A-type can be degraded by human gut microbiota. The microbial metabolites may contribute to the bioactivities of procyanidins.

Non-toxic plant metabolites regulate Staphylococcus viability and biofilm formation: a natural therapeutic strategy useful in the treatment and prevention of skin infections.

Posted: 
April 1, 2015
Authors: 
Morán A, Gutiérrez S, Martínez-Blanco H, Ferrero MA, Monteagudo-Mera A, Rodríguez-Aparicio LB.
Journal: 
Biofouling 30(10):1175-82.
Abstract: 

In the present study, the efficacy of generally recognised as safe (GRAS) antimicrobial plant metabolites in regulating the growth of Staphylococcus aureus and S. epidermidis was investigated. Thymol, carvacrol and eugenol showed the
strongest antibacterial action against these microorganisms, at a subinhibitory concentration (SIC) of ≤ 50 μg ml(-1). Genistein, hydroquinone and resveratrol showed antimicrobial effects but with a wide concentration range (SIC = 50-1,000 μg ml(-1)), while catechin, gallic acid, protocatechuic acid, p-hydroxybenzoic acid and cranberry extract were the most biologically compatible molecules (SIC ≥ 1000 μg ml(-1)). Genistein, protocatechuic acid, cranberry extract, p-hydroxybenzoic acid and resveratrol also showed anti-biofilm activity against S. aureus, but not against S. epidermidis in which, surprisingly, these metabolites stimulated biofilm formation (between 35% and 1,200%). Binary combinations of cranberry extract and resveratrol with genistein, protocatechuic or p-hydroxibenzoic acid enhanced the stimulatory effect on S. epidermidis biofilm formation and maintained or even increased S. aureus anti-biofilm
activity.

Anti-adhesion activity of A2-type proanthocyanidins (a cranberry major component) on uropathogenic E. coli and P. mirabilis strains.

Posted: 
July 25, 2014
Authors: 
Nicolosi D, Tempera G, Genovese C, Furneri PM
Journal: 
Antibiotics 3(2):143-54
Abstract: 

Urinary tract infections (UTIs) are relatively common in women and may be classified as uncomplicated or complicated, depending upon the urinary tract anatomy and physiology. Acute uncomplicated cystitis (AUC) occurs when urinary pathogens from the bowel or vagina colonize the periurethral mucosa and reach the bladder. The vast majority of episodes in healthy women involving the same bacterial strain that caused the initial infection are thought to be reinfections. About 90% of AUC are caused by uropathogenic Escherichia coli (UPEC), but Proteus mirabilis also plays an important role. Several studies support the importance of cranberry (Vaccinium macrocarpon) proanthocyanidins in preventing adhesion of P-fimbriated UPEC to uroepithelial cells. In this study, we evaluated the in vitro anti-adhesion activity of A2-linked proanthocyanidins from cranberry on a UPEC and Proteus mirabilis strains and their possible influence on urease activity of the latter. A significant reduction of UPEC adhesion (up to 75%) on the HT1376 cell line was observed vs. control. For the strains of P. mirabilis there was also a reduction of adhesion (up to 75%) compared to controls, as well as a reduction in motility and urease activity. These results suggest that A2-type cranberry proanthocyanidins could aid in maintaining urinary tract health.

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

Posted: 
July 25, 2014
Authors: 
Rane HS, Bernardo SM, Howell AB, Lee SA
Journal: 
J Antimicrob Chemother 69(2):428-36
Abstract: 

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.

Evaluating the binding of selected biomolecules to cranberry derived proanthocyanidins using the quartz crystal microbalance.

Posted: 
July 25, 2014
Authors: 
Weckman NE, Olsson AL, Tufenkji N
Journal: 
Biomacromolecules 15(4):1375-81
Abstract: 

Despite cranberry being associated with the prevention of bacterial infections for over a century, our understanding of the bioavailability and mechanisms by which cranberry prevents infection is limited. This study investigates the interactions between cranberry proanthocyanidins (CPAC) and human serum proteins (albumin, alpha-1-acid glycoprotein, and fibrinogen) that may be encountered during CPAC metabolism following ingestion. To better understand how CPAC might interfere with bacterial infection, we also examined the interactions between CPAC and selected bacterial virulence factors; namely, lipopolysaccharide (LPS) and rhamnolipid. The binding of CPAC to the serum proteins, rhamnolipids and LPS from Escherichia coli O111:B4 can be described by Langmuir-type isotherms, allowing the determination of the apparent adsorption affinity constants, with CPAC interacting most strongly with fibrinogen with a binding constant of 2.2 x 10(8) M(-1). These binding interactions will limit the bioavailability of the CPAC at the site of action, an important consideration in designing further clinical trials. Furthermore, CPAC interacts with Pseudomonas aeruginosa 10 LPS, E. coli O111:B4 LPS, and P. aeruginosa rhamnolipids in fundamentally different manners, supporting the theory that cranberry prevents bacterial infections via multiple mechanisms.

Ratio of "A-type" to "B-type" proanthocyanidin interflavan bonds affects extra-intestinal pathogenic Escherichia coli invasion of gut epithelial cells.

Posted: 
July 25, 2014
Authors: 
Feliciano RP, Meudt JJ, Shanmuganayagam D, Krueger CG, Reed JD
Journal: 
J Agric Food Chem 62(18):3919-25
Abstract: 

Gut colonization by extra-intestinal pathogenic Escherichia coli (ExPEC) increases the risk of subsequent infections, including urinary tract infection and septicemia. Previous work suggests that cranberry proanthocyanidins (PAC) interact with bacterial surface factors, altering bacterial interaction with host cells. Methods were developed to determine if ratios of "A-type" to "B-type" interflavan bonds in PAC affect ExPEC agglutination and invasion of enterocytes. In cranberries, 94.5% of PAC contain one or more "A-type" bonds, whereas in apples, 88.3% of PAC contain exclusively "B-type" bonds. Results show that cranberry "A-type" PAC have greater bioactivity than apple "B-type" PAC for increasing ExPEC agglutination and decreasing ExPEC epithelial cell invasion.

Cranberry impairs selected behaviors essential for virulence in Proteus mirabilis HI4320

Posted: 
September 15, 2013
Authors: 
McCall J, Hidalgo G, Asadishad B, Tufenkji N
Journal: 
Can J Microbiol 59(6):430-436
Abstract: 

Proteus mirabilis is an etiological agent of complicated urinary tract infections. North American cranberries (Vaccinium macrocarpon) have long been considered to have protective properties against urinary tract infections. This work reports the effects of cranberry powder (CP) on the motility of P. mirabilis HI4320 and its expression of flaA, flhD, and ureD. Our results show that swimming and swarming motilities and swarmer-cell differentiation were inhibited by CP. Additionally, transcription of the flagellin gene flaA and of flhD, the first gene of the flagellar master operon flhDC, decreased during exposure of P. mirabilis to various concentrations of CP. Moreover, using ureD-gfp, a fusion of the urease accessory gene ureD with gfp, we show that CP inhibits urease expression. Because we demonstrate that CP does not inhibit the growth of P. mirabilis, the observed effects are not attributable to toxicity. Taken together, our results demonstrate that CP hinders motility of P. mirabilis and reduces the expression of important virulence factors.

Inhibition of bacterial motility and spreading via release of cranberry derived materials from silicone substrates

Posted: 
September 15, 2013
Authors: 
Chan M, Hidalgo G, Asadishad B, Almeida S, Muja N, Mohammadi MS, Nazhat SN, Tufenkji N
Journal: 
Colloid Surface B 110:275-80
Abstract: 

The motility of bacteria plays a key role in their colonization of surfaces during infection. Derivatives of cranberry fruit have been shown to interfere with bacterial motility. Herein, we report on the incorporation of cranberry derived materials (CDMs) into silicone substrates with the aim of impairing bacterial pathogen motility and spreading on the substrate surface. The release of CDMs from the silicone substrates when soaking in an aqueous medium was quantified for a period of 24h. Next, we showed that CDMs released from two silicone substrates remain bioactive as they downregulate the expression of the flagellin gene of two key uropathogens - Escherichia coli CFT073 and Proteus mirabilis HI4320. Furthermore, we demonstrate that CDM-modified silicone inhibits the swarming motility of P. mirabilis, an aggressive swarmer. The bioactive, CDM-modified substrates can find broad applications in the medical device and food industries where the impairment of bacterial colonization of surfaces is of paramount importance.

The effect of American cranberry (Vaccinium macrocarpon) constituents on the growth inhibition, membrane integrity, and injury of Escherichia coli O157:H7 and Listeria monocytogenes in comparison to Lactobacillus rhamnosus.

Posted: 
September 15, 2013
Authors: 
Lacombe A, McGivney C, Tadepalli S, Sun XiaoHong Wu VCH
Journal: 
Food Microbiol 34(2):352-359
Abstract: 

The antimicrobial properties of the American cranberry were studied against Escherichia coli O157:H7, Listeria monocytogenes, and Lactobacillus rhamnosus to determine the effects on growth inhibition, membrane permeability, and injury. Cranberry powder was separated using a C-18 Sep-Pak cartridge into sugars plus organic acids (F1), monomeric phenolics (F2), and anthocyanins plus proanthocyanidins (F3). Fraction 3 was further separated into anthocyanins (F4) and proanthocyanidins (F5) using an LH-20 Sephadex column. Each fraction was diluted in the brain heart infusion (BHI) broth to determine the minimum inhibitory/bactericidal concentrations (MIC/MBC). L. monocytogenes was the most susceptible to cranberry fraction treatment with the lowest MIC/MBC for each treatment, followed by E. coli O157:H7 and L. rhamnosus. Membrane permeability and potential was studied using LIVE/DEAD viability assay and using Bis (1, 3-dibutylbarbituric acid) trimethine oxonol (DiBAC4), respectively. L. rhamnosus demonstrated the highest permeability followed by E. coli O157:H7, and L. monocytogenes. L. rhamnosus demonstrated the highest recovery followed by E. coli O157:H7, and L. monocytogenes. Each cranberry fraction demonstrated membrane hyperpolarization at their native pH, while F2, F3, and F5 demonstrated membrane depolarization at neutral pH. With this knowledge cranberry compounds may be used to prevent maladies and potentially substitute for synthetic preservatives and antibiotics.

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