Effects of an Apple Extract on Glycaemia: The GLU-Pomme Study

NCT ID: NCT02940249

Last Updated: 2020-06-17

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 34 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-01-31
• Study Completion Date: 2018-02-28

Brief Summary

Postprandial hyperglycaemia can lead to adverse modifications to functional proteins within the body and eventually lead to the development of type 2 diabetes. Previous research by this group has shown that an apple polyphenol extract reduced hyperglycaemia following a high-carbohydrate meal. The aim of this study is to investigate the effects of lower doses of the apple extract on postprandial glycaemia, insulinaemia and plasma gastric inhibitory polypeptide concentrations following a mixed carbohydrate test meal.

Detailed Description

Introduction:

Sharp peaks in blood glucose levels can lead to adverse modifications to functional proteins, oxidative stress and pancreatic beta cell dysfunction. It is therefore desirable to consume a diet that will allow more gradual rises in blood glucose levels after meals. Fruit polyphenols may help to limit the glucose excursion following a high carbohydrate meal. Previous research by this research group has demonstrated that 1200 mg of apple polyphenols (Appl'In™) inhibited the average incremental area under the curve (T+0 to T+30 min) of plasma glucose by 54% relative to placebo. Possible mechanisms include inhibition of intestinal enzymes and inhibition of intestinal glucose absorption by decreasing SGLT1/GLUT2 transport activity. The literature also suggests that foods rich in polyphenols exert beneficial effects on risk factors of cardiovascular disease such as hypertension, lipid metabolism and vascular function.

Study design:

A randomised, controlled, double-blind, cross-over study will be conducted. Four matched test drinks will be consumed in random order on separate study visits immediately before a mixed-carbohydrate test meal, containing either: 1) 1.2 g, 2) 0.9 g 3). 0.6 g of apple polyphenols, or 4). placebo. Postprandial changes in plasma glucose, insulin, NEFA, GIP, GLP-1 concentrations as well as changes in vascular function will be measured. Twenty-four hour urine samples will be collected for analysis of urinary polyphenol metabolites and glucose. In a sub sample of participants, a paracetamol absorption test will be incorporated via addition of 1.5 g paracetamol into the test drink.

Conditions

Prevention of Hyperglycaemia

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: PREVENTION
• Blinding Strategy: DOUBLE

Study Groups

1.2 g apple polyphenols

1200 mg apple polyphenols delivered in a low sugar drink.

Group Type: EXPERIMENTAL

Apple polyphenols

Intervention Type: DIETARY_SUPPLEMENT

Drinks will be delivered in random order at 4 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.

0.9 g apple polyphenols

900 mg apple polyphenols delivered in a low sugar drink.

Group Type: EXPERIMENTAL

Apple polyphenols

Intervention Type: DIETARY_SUPPLEMENT

Drinks will be delivered in random order at 4 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.

0.6 g apple polyphenols

600 mg apple polyphenols delivered in a low sugar drink.

Group Type: EXPERIMENTAL

Apple polyphenols

Intervention Type: DIETARY_SUPPLEMENT

Drinks will be delivered in random order at 4 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.

Placebo

No polyphenols delivered in a low sugar drink.

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DIETARY_SUPPLEMENT

Interventions

Apple polyphenols

Drinks will be delivered in random order at 4 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.

Intervention Type: DIETARY_SUPPLEMENT

Placebo

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• Age: 18-70 y
• Male and female

Exclusion Criteria

• Body Mass Index 18-35 kg/m2
• Able to understand the information sheet and willing to comply with study protocol
• Able to give informed written consent

• Those diagnosed with Phenylketonuria (PKU)
• Those with known or suspected food and/or paracetamol intolerances, allergies or hypersensitivity
• Women who are known to be pregnant or who are intending to become pregnant over the course of the study
• Women who are breast feeding
• Participation in another clinical trial
• Those who have donated blood within 3 months of the screening visit and participants for whom participation in this study would result in having donated more than 1500 millilitres of blood in the previous 12 months.
• Full Blood Counts and Liver Function test results outside of the normal range.
• Current smokers, or reported giving up smoking within the last 6 months
• History of substance abuse or alcoholism
• Reported history of Cardiovascular disease, diabetes (or fasting glucose ≥ 7.1 mmol/L), cancer, kidney, liver or bowel disease, gastrointestinal disorder or use of drug likely to alter gastrointestinal function
• Unwilling to restrict consumption of specified high polyphenol foods for 48 h before the study
• Weight change >3kg in preceding 2 months and body mass index <18 or >35 kg/m2
• Blood pressure ≥160/100 mmHg
• Total cholesterol ≥ 7.5 mmol/L; fasting triacylglycerol concentrations ≥ 5.0 mmol/L
• Medications that may interfere with the study: alpha-glucosidase inhibitors (acarbose: Glucobay), insulin sensitizing drugs (metformin: Glucophage, Glucophage SR, Eucreas, Janumet; thiazolidinediones: Actos, Competact), sulfonylureas (Daonil, Diamicron, Diamicron MR, Glibenese, Minodiab, Amaryl Tolbutamide), and lipid lowering drugs (statins, nicotinic acid, colestyramine anhydrous, ezetimibe, fibrates); and medications that may react unpredictably with paracetamol: ketoconazole, metoclopramide, carbamazepine, phenobarbital, phenytoin, primidone, warfarin and other products containing paracetamol. Other medications should be reviewed by medical representative from KCL on a case by case basis.
• Nutritional supplements that may interfere with the study: higher dose vitamins/minerals (>200% Recommend Nutrient Intake), B vitamins, Vitamin C, calcium, copper, chromium, iodine, iron, magnesium, manganese, phosphorus, potassium and zinc. Subjects already taking vitamin or minerals at a dose around 100% or less up to 200% of the RNI, or evening primrose/algal/fish oil supplements will be asked to maintain habitual intake patterns, ensuring that they take them every day and not sporadically. They will be advised not to stop taking supplements or start taking new supplements during the course of the study.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

DIANA Food

INDUSTRY

Sponsor Role: collaborator

King's College London

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Metabolic Research Unit at King's College London

Waterloo Campus, London, United Kingdom

Countries

United Kingdom

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Other Identifiers

GLU-Pomme

Identifier Type: -

Identifier Source: org_study_id