A Single Supplement of a Standardised Bilberry Extract Modifies Glycaemic Response

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
University of Aberdeen
ClinicalTrials.gov Identifier:
NCT01245270
First received: November 16, 2010
Last updated: August 13, 2014
Last verified: August 2014
Results First Received: August 23, 2013  
Study Type: Interventional
Study Design: Allocation: Randomized;   Endpoint Classification: Efficacy Study;   Intervention Model: Crossover Assignment;   Masking: Double Blind (Subject, Investigator);   Primary Purpose: Treatment
Condition: Type 2 Diabetes
Interventions: Dietary Supplement: Bilberry capsule first, then control cap
Dietary Supplement: Control capsule first then bilberry cap

  Participant Flow
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Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
Eight male volunteer subjects with T2D controlled by diet and lifestyle alone or with impaired glucose tolerance were recruited from the Aberdeen area of the UK. Subjects were only included if they were not on any special religious or prescribed diet and had a stable weight.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
No text entered.

Reporting Groups
  Description
Single Control Capsule First Then Bilberry Capsule In a cross-over design, volunteers (n 8) were randomised and double-blinded into two groups matched for BMI as well as age and given a single capsule of either 0·47 g of Mirtoselect® (a standardised bilberry extract (36 % (w/w) anthocyanins)) which equates to about 50 g of fresh bilberries formulated in gelatin capsules or a control capsule consisting of microcrystalline cellulose in an opaque gelatin capsule, followed by oral glucose tolerance testing (OGTT). The reverse procedure was conducted following a 2-week washout period. The volunteers were asked to consume a low-phytochemical diet 3 d before taking the capsule and for the 24 h after taking the capsule on both occasions. In addition the volunteers were asked to record what they ate over the same period in a food diary to ensure that they adhered to the low-phytochemical diet. Subjects were reimbursed travelling expenses on completion of the study.
Single Bilberry Capsule First Then Control Capsule In a cross-over design, volunteers (n 8) were randomised and double-blinded into two groups matched for BMI as well as age and given a single capsule of either 0·47 g of Mirtoselect® (a standardised bilberry extract (36 % (w/w) anthocyanins)) which equates to about 50 g of fresh bilberries formulated in gelatin capsules or a control capsule consisting of microcrystalline cellulose in an opaque gelatin capsule, followed by oral glucose tolerance testing (OGTT). The reverse procedure was conducted following a 2-week washout period. The volunteers were asked to consume a low-phytochemical diet 3 d before taking the capsule and for the 24 h after taking the capsule on both occasions. In addition the volunteers were asked to record what they ate over the same period in a food diary to ensure that they adhered to the low-phytochemical diet. Subjects were reimbursed travelling expenses on completion of the study.

Participant Flow:   Overall Study
    Single Control Capsule First Then Bilberry Capsule     Single Bilberry Capsule First Then Control Capsule  
STARTED     4 [1]   4 [1]
COMPLETED     4 [1]   4 [1]
NOT COMPLETED     0     0  
[1] In a cross-over design, volunteers (n=8) were randomised and double blinded into two groups (n=4)



  Baseline Characteristics
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Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
  Description
Bilberry Capsule First, Then Control Capsule In a cross-over design, eight volunteers were randomised and double-blinded into two groups matched for BMI as well as age and given a single capsule of either 0·47 g of Mirtoselect® (a standardised bilberry extract (36 % (w/w) anthocyanins)) which equates to about 50 g of fresh bilberries formulated in gelatin capsules or a control capsule consisting of microcrystalline cellulose in an opaque gelatin capsule, followed by oral glucose tolerance testing (OGTT). The reverse procedure was conducted following a 2-week washout period. The volunteers were asked to consume a low-phytochemical diet 3 d before taking the capsule and for the 24 h after taking the capsule on both occasions. In addition the volunteers were asked to record what they ate over the same period in a food diary to ensure that they adhered to the low-phytochemical diet. Subjects were reimbursed travelling expenses on completion of the study.
Control Capsule First, Then Bilberry Capsule In a cross-over design, eight volunteers were randomised and double-blinded into two groups matched for BMI as well as age and given a single capsule of either 0·47 g of Mirtoselect® (a standardised bilberry extract (36 % (w/w) anthocyanins)) which equates to about 50 g of fresh bilberries formulated in gelatin capsules or a control capsule consisting of microcrystalline cellulose in an opaque gelatin capsule, followed by oral glucose tolerance testing (OGTT). The reverse procedure was conducted following a 2-week washout period. The volunteers were asked to consume a low-phytochemical diet 3 d before taking the capsule and for the 24 h after taking the capsule on both occasions. In addition the volunteers were asked to record what they ate over the same period in a food diary to ensure that they adhered to the low-phytochemical diet. Subjects were reimbursed travelling expenses on completion of the study.
Total Total of all reporting groups

Baseline Measures
    Bilberry Capsule First, Then Control Capsule     Control Capsule First, Then Bilberry Capsule     Total  
Number of Participants  
[units: participants]
  4     4     8  
Age  
[units: participants]
     
<=18 years     0     0     0  
Between 18 and 65 years     4     4     8  
>=65 years     0     0     0  
Age  
[units: years]
Mean ± Standard Deviation
  62  ± 5     62  ± 5     62  ± 5  
Gender  
[units: participants]
     
Female     0     0     0  
Male     4     4     8  
Region of Enrollment  
[units: participants]
     
United Kingdom     4     4     8  
BMI  
[units: Kg/m2]
Mean ± Standard Deviation
  30  ± 4     30  ± 4     30  ± 4  



  Outcome Measures
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1.  Primary:   Plasma Glucose iAUC (Incremental Area Under the Curve; mM*Min)   [ Time Frame: Plasma was collected at -15, -10 and -5 (fasted) and at 15, 30, 45, 60, 90, 120, 150 and 300 min post capsule ]

2.  Primary:   Plasma Insulin iAUC (Incremental Area Under the Curve; ng/ml*Min)   [ Time Frame: Plasma was collected at -15, -10 and -5 (fasted) and at 15, 30, 45, 60, 90, 120, 150 and 300 min after the capsule ]

3.  Secondary:   Bioavailability in Plasma   [ Time Frame: Plasma will also be collected -15,-10, -5, 15, 30, 45, 60, 90, 120, 150, and 300 minutes and 24 hours post intervention ]
Results not yet reported.   Anticipated Reporting Date:   01/2014   Safety Issue:   No

4.  Secondary:   Bioavailability in Urine   [ Time Frame: Urine will also be collected (if possible) 0, 1, 3 and 5 hours, with all urine collected within the 24 hour time period post intervention ]
Results not yet reported.   Anticipated Reporting Date:   01/2014   Safety Issue:   No


  Serious Adverse Events


  Other Adverse Events


  Limitations and Caveats
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Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
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  More Information
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Certain Agreements:  
All Principal Investigators ARE employed by the organization sponsoring the study.


Results Point of Contact:  
Name/Title: Dr Nigel Hoggard
Organization: University of Aberdeen Rowett Institute of Nutrition and Health
phone: [+44] (0) 1224 438700
e-mail: N.Hoggard@abdn.ac.uk


Publications:

Responsible Party: University of Aberdeen
ClinicalTrials.gov Identifier: NCT01245270     History of Changes
Other Study ID Numbers: REC 10/S0801/54, 902
Study First Received: November 16, 2010
Results First Received: August 23, 2013
Last Updated: August 13, 2014
Health Authority: United Kingdom: Research Ethics Committee