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Effect of cranberry extracts on lipid profiles in subjects with Type 2 diabetes

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Authors
Lee IT, Chan YC, Lin CW, Lee WJ, Sheu WH
Journal
Diabet Med 25(12):1473-7
Abstract

AIM: To examine the effect of cranberry ingestion on lipid profiles in Type 2 diabetic patients taking oral glucose-lowering drugs.

METHODS: Thirty Type 2 diabetic subjects (16 males and 14 females; mean age 65 +/- 1 years) who were taking oral glucose-lowering medication regularly were enrolled in this randomized, placebo-controlled, double-blind study. Changes in lipid profiles, oxidized low-density lipoprotein (ox-LDL), glycaemic control, components of the metabolic syndrome, C-reactive protein (CRP) and urinary albumin excretion (UAE) were assessed after cranberry or placebo treatment for 12 weeks.

RESULTS: Low-density lipoprotein (LDL) cholesterol decreased significantly in the cranberry group (from 3.3 +/- 0.2 to 2.9 +/- 0.2 mmol/l, P = 0.005) and the decrease was significantly greater than that in the placebo group (-0.4 +/- 0.1 vs. 0.2 +/- 0.1 mmol/l, P 0.001). Total cholesterol and total : high-density lipoprotein (HDL) cholesterol ratio also decreased significantly (P = 0.020 and 0.044, respectively) in the cranberry group and the reductions were significantly different from those in the placebo group (P 0.001 and P = 0.032, respectively). However, ox-LDL levels did not change significantly in response to cranberry consumption. Neither fasting glucose nor glycated haemoglobin improved in either group. Changes in components of the metabolic syndrome, UAE and CRP were not significantly different between groups.

CONCLUSIONS: Cranberry supplements are effective in reducing atherosclerotic cholesterol profiles, including LDL cholesterol and total cholesterol levels, as well as total : HDL cholesterol ratio, and have a neutral effect on glycaemic control in Type 2 diabetic subjects taking oral glucose-lowering agents.

Effectiveness of a cranberry (Vaccinium macrocarpon) preparation in reducing asymptomatic bacteriuria in patients with an ileal enterocystoplasty.

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Authors
Botto H, Neuzillet Y
Journal
Scand J Urol Nephrol 44(3):165-8
Abstract

OBJECTIVE: Bacteriuria is a usual complication of enterocystoplasty following cystectomy. Cranberry products may decrease the number of urinary tract infections because of a non-dialysable compound, a condensed tannin, the proanthocyanidin (PAC) type A. This study determined the effectiveness of treatment with a cranberry preparation highly dosed in proanthocyanidin A in prevention of repeated bacteriuria in patients with an ileal enterocystoplasty.

MATERIAL AND METHODS: Between November 2004 and November 2009, a controlled study was open to patients seen in consultation for follow-up after a radical cystectomy and ileal cystoplasty. Patients had a history of repeated urinary infection and/or bacteriuria during the pretreatment phase. During the treatment phase, patients received a cranberry (Vaccinium macrocarpon) preparation highly dosed in proanthocyanidin A (36 mg measured by the dimethylaminocinnamaldehyde method), one capsule a day. The primary endpoint was the absence of bacteria in urine culture. The secondary endpoints were the presence or absence of symptoms (pain, fever), continence status and upper excretory tract enlargement. Each patient was his or her own historical control.

RESULTS: Fifteen patients were included. The median duration of the period without treatment with cranberry compound was 18.5 (1-93) months. The median duration of the period with treatment with cranberry compound was 32.8 (13-60) months. There was a significant decrease in the number of positive urine cultures during cranberry compound treatment.

CONCLUSIONS: Treatment with a cranberry compound seems to be effective in reducing asymptomatic bacteriuria in patients with an ileal enterocystoplasty. These results need to be validated by further double-blind randomized studies.

Effects of a flavonol-rich diet on select cardiovascular parameters in a Golden Syrian hamster model.

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Authors
Kalgaonkar S, Gross HB, Yokoyama W, Keen CL
Journal
J Med Food 13(1):108-15
Abstract

The concept that the consumption of a diet rich in flavonoids can be associated with a reduced risk for cardiovascular disease is becoming increasingly accepted. In the present study we investigated the effects of the following four diets on blood pressure and cholesterol ester levels in hypercholesterolemic Golden Syrian hamsters: a high-fat, high-cholesterol diet (HFHC); a HFHC with 2% cranberry concentrate powder (HFHC+CE); a HFHC with 0.1% rutin (HFHC+Rutin); and a HFHC with 30 mg/kg vitamin E (HFHC+Vit.E). Diets were fed for either 12 or 20 weeks. Over the experimental period, heart rate and blood pressure measurements increased in the animals fed HFHC and HFHC+Vit.E; in contrast, these measurements were not increased in the animals fed HFHC+CE and HFHC+Rutin. Mesenteric and total abdominal fat were significantly lower in the animals fed HFHC+Rutin than in animals fed the other three diets. Ratios of plasma high-density lipoprotein cholesterol (HDL-C) to very-low-density lipoprotein cholesterol and of plasma HDL-C to low-density lipoprotein cholesterol were significantly higher in animals consuming HFHC+Vit.E than in animals fed the other three diets. Aortic cholesteryl ester levels were significantly lower in animals fed HFHC+CE, HFHC+Rutin, and HFHC+Vit.E at 20 weeks than in the animals fed HFHC. Fasting blood glucose concentrations were significantly lower in animals fed HFHC+Rutin and HFHC+Vit.E, and glucose clearance rates improved in animals fed HFHC+Rutin compared to animals fed the other three diets. Results obtained from this study support the concept that the chronic consumption of a flavonoid-rich diet can be beneficial

Evaluation of cranberry tablets for the prevention of urinary tract infections in spinal cord injured patients with neurogenic bladder.

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Authors
Hess MJ, Hess PE, Sullivan MR, Nee M, Yalla SV
Journal
Spinal Cord 46(9):622-6
Abstract

STUDY DESIGN: Randomized, double blind, placebo-controlled trial with a crossover design.

OBJECTIVE: To evaluate cranberry tablets for the prevention of urinary tract infection (UTI) in spinal cord injured (SCI) patients.

SETTING: Spinal Cord Injury Unit of a Veterans Administration Hospital, MA, USA.

METHODS: Subjects with spinal cord injury and documentation of neurogenic bladder were randomized to receive 6 months of cranberry extract tablet or placebo, followed by the alternate preparation for an additional 6 months. The primary outcome was the incidence of UTI.

RESULTS: Forty-seven subjects completed the trial. We found a reduction in the likelihood of UTI and symptoms for any month while receiving the cranberry tablet (P0.05 for all). During the cranberry period, 6 subjects had 7 UTI, compared with 16 subjects and 21 UTI in the placebo period (P0.05 for both number of subjects and incidence). The frequency of UTI was reduced to 0.3 UTI per year vs 1.0 UTI per year while receiving placebo. Subjects with a glomerular filtration rate (GFR) greater than 75 ml min(-1) received the most benefit.

CONCLUSION: Cranberry extract tablets should be considered for the prevention of UTI in SCI patients with neurogenic bladder. Patients with a high GFR may receive the most benefit.

Influence of cranberry juice on glucan-mediated processes involved in Streptococcus mutans biofilm development.

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Authors
Koo H, Nino de Guzman P, Schobel BD, Vacca Smith AV, Bowen WH.
Journal
Caries Res 40(1):20-27
Abstract

Cranberry juice (CJ) has biological properties that may provide health benefits. In this study, we investigated the influence of CJ (pH 5.5) on several activities in vitro associated with the development of Streptococcus mutans UA159 biofilms. The ability of CJ to influence the adherence of S. mutans to either saliva- (sHA) or glucan-coated hydroxyapatite (gsHA), and to inhibit the glucan production by purified glucosyltransferases adsorbed to sHA was determined. For the adherence assays, we used both uncoated and saliva-coated bacterial cells. Furthermore, we examined whether CJ interferes with the viability, development, polysaccharide composition and acidogenicity of S. mutans biofilms. A solution containing equivalent amounts of glucose, fructose and organic acids at pH 5.5 was used as negative control. The adherence of S. mutans (uncoated and saliva-coated) to either sHA or gsHA treated with 25% CJ (v/v) was remarkably reduced (40-85% inhibition compared to control: p 0.05), indicating that CJ effectively blocked the bacterial adherence to binding sites in salivary pellicle and in glucans. In contrast, when the bacterial cells alone were treated with CJ they adhered to the similar untreated surfaces. Cranberry juice (25%, v/v) also inhibited the activities of surface-adsorbed GTF B and C (70-80% inhibition compared to control, p 0.05). The effect of CJ on the viability of microorganisms in biofilms was not significant. Biofilm formation and accumulation were significantly reduced by topical applications of 25% CJ (v/v) twice daily with 1-min exposures (p 0.05). The biomass and insoluble glucan content of the biofilms in addition to its acidogenicity were significantly reduced by cranberry treatments (p 0.05). Our data show that cranberry juice inhibited glucan-mediated biofilm development and acid production, and holds promise as a natural product to prevent biofilm-related oral diseases.

Influence of cranberry proanthocyanidins on formation of biofilms by Streptococcus mutans on saliva-coated apatitic surface and on dental caries development in vivo.

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Authors
Koo H, Duarte S, Murata RM, Scott-Anne K, Gregoire S, Watson GE, Singh AP, Vorsa N.
Journal
Caries Res 44(2):116-126
Abstract

Cranberry crude extracts, in various vehicles, have shown inhibitory effects on the formation of oral biofilms in vitro. The presence of proanthocyanidins (PAC) in cranberry extracts has been linked to biological activities against specific virulence attributes of Streptococcus mutans, e.g. the inhibition of glucosyltransferase (Gtf) activity. The aim of the present study was to determine the influence of a highly purified and chemically defined cranberry PAC fraction on S. mutans biofilm formation on saliva-coated hydroxyapatite surface, and on dental caries development in Sprague-Dawley rats. In addition, we examined the ability of specific PAC (ranging from low-molecular-weight monomers and dimers to high-molecular-weight oligomers/polymers) to inhibit GtfB activity and glycolytic pH drop by S. mutans cells, in an attempt to identify specific bioactive compounds. Topical applications (60-second exposure, twice daily) with PAC (1.5 mg/ml) during biofilm formation resulted in less biomass and fewer insoluble polysaccharides than the biofilms treated with vehicle control had (10% ethanol, v/v; p 0.05). The incidence of smooth-surface caries in rats was significantly reduced by PAC treatment (twice daily), and resulted in less severe carious lesions compared to the vehicle control group (p 0.05); the animals treated with PAC also showed significantly less caries severity on sulcal surfaces (p 0.05). Furthermore, specific A-type PAC oligomers (dimers to dodecamers; 0.1 mg/ml) effectively diminished the synthesis of insoluble glucans by GtfB adsorbed on a saliva-coated hydroxyapatite surface, and also affected bacterial glycolysis. Our data show that cranberry PAC reduced the formation of biofilms by S. mutans in vitro and dental caries development in vivo, which may be attributed to the presence of specific bioactive A-type dimers and oligomers.

Inhibitory effect of cranberry polyphenol on biofilm formation and cysteine proteases of Porphyromonas gingivalis

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Authors
Yamanaka A, Kouchi T, Kasai K, Kato T, Ishihara K, Okuda K.
Journal
J Periodontal Res 42(6):589-592
Abstract

BACKGROUND AND OBJECTIVE: The purpose of this study was to investigate the effects of cranberry polyphenol fraction on biofilm formation and activities of Arg-gingipain and Lys-gingipain in Porphyromonas gingivalis.

MATERIAL AND METHODS: The polyphenol fraction was prepared by using a glass column packed with Amberlite XAD 7HP and 70% aqueous ethanol as an elution solvent.

RESULTS: Synergistic biofilm formation by P. gingivalis and Fusobacterium nucleatum was significantly inhibited by the polyphenol fraction at a concentration of 250 microg/mL compared with untreated controls (p 0.01). Arg-gingipain and Lys-gingipain activities in P. gingivalis ATCC 33277 and FDC 381 were inhibited significantly at a polyphenol fraction concentration of > or = 1 microg/mL (p 0.05).

CONCLUSION: These findings indicate that the polyphenol fraction inhibits biofilm formation and the Arg-gingipain and Lys-gingipain activities of P. gingivalis.

Inhibitory effects of cranberry juice on attachment of oral streptococci and biofilm formation

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Authors
Yamanaka A, Kimizuka R, Kato T, Okuda K
Journal
Oral Microbiol Immunol 19(3):150-4
Abstract

Cranberry juice is known to inhibit bacterial adhesion. We examined the inhibitory effect of cranberry juice on the adhesion of oral streptococci strains labeled with [3H]-thymidine to saliva-coated hydroxyapatite beads (s-HA). When the bacterial cells were momentarily exposed to cranberry juice, their adherence to s-HA decreased significantly compared with the control (P 0.01). Their hydrophobicity also decreased dependently with the concentration of cranberry juice. We also evaluated the inhibitory effect of cranberry juice on biofilm formation. By using a microplate system, we found that the high molecular mass constituents of cranberry juice inhibited the biofilm formation of the tested streptococci. The inhibitory activity was related to the reduction of the hydrophobicity. The present findings suggest that cranberry juice component(s) can inhibit colonization by oral streptococci to the tooth surface and can thus slow development of dental plaque.

Long-term effects of three commercial cranberry products on the antioxidative status in rats: a pilot study.

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Authors
Palikova I, Vostalova J, Zdarilova A, Svobodova A, Kosina P, Vecera R, Stejskal D, Proskova J, Hrbac J, Bednar P, Maier V, Cernochova D, Simanek V, Ulrichova J.
Journal
J Agric Food Chem 8(3):1672-8
Abstract

Cranberry (Vaccinium macrocarpon Ait. Ericaceae) fruits and juice are widely used for their antiadherence and antioxidative properties. Little is known however about their effects on clinical chemistry markers after long-term consumption. This study was conducted to evaluate the effect of three commercial cranberry products, NUTRICRAN90S, HI-PAC 4.0, and PACRAN on the antioxidative status of rodents, divided into three experimental groups. The products were given as dietary admixtures (1500 mg of product/kg of stock feed) for 14 weeks to male Wistar rats (Groups 2-4) and a control Group 1 which received only stock feed. There were no significant cranberry treatment-related effects on oxidative stress parameters, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase, superoxide dismutase, total antioxidant capacity, thiobarbituric acid reactive substances, advanced oxidation protein products, total SH-groups, or any other measured clinical chemistry markers. Hematological parameters, body weight, and food consumption were also unaffected by intake of cranberries. Only liver glutathione reductase activity and glutathione levels were significantly lower in Group 4 than in Group 1. Plasma alkaline phosphatase alone was significantly decreased in Group 2. No gross pathology, effects on organ weights, or histopathology were observed. No genotoxicity was found, and total cytochrome P450 level in liver was unaffected in all groups. The levels of hippuric acid and several phenolic acids were significantly increased in plasma and urine in Groups 2-4. The concentration of anthocyanins was under the detection threshold. The dietary addition of cranberry powders for 14 weeks was well tolerated, but it did not improve the antioxidative status in rats.

Recurrent urinary tract infections in older people: the role of cranberry products

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Authors
Sumukadas D, Davey P and McMurdo ME
Journal
Age Ageing 38(3):255-7
Abstract

No abstract - Introduction: Urinary tract infections (UTI) are the commonest bacterial infection in older people. Half of all women experience at least one UTI and the risk increases with age. The present management of recurrent urinary tract infection is prophylaxis with low-dose, long-term antibiotics. However, there is a growing reluctance to prescribe antibiotics unless absolutely essential because of fears about antimicrobial resistance. So the recent resurgence in interest in the potential role of cranberry
products is timely.