Clinical trial NCT02041104: Impact of Consumption of Beta-glucans on the Intestinal Microbiota and Glucose and Lipid Metabolism
Official title: Impact of Consumption of Beta-glucans on the Intestinal Microbiota and Glucose and Lipid Metabolism in a Population With Metabolic Syndrome
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Metabolic Syndrome
Dyslipidemia
Obesity, Abdominal
Hyperglycemia
Hypertension
Keywords: Metabolic syndrome
4 -week intervention
Randomised placebo controlled parallel study
Beta-glucans
Abdominal fat
Dyslipidemia
Insulin resistance
Hypertension
Gut Microbiota Composition
Oral Glucose Tolerance Test
Lipid Profile
Real-Time Polymerase Chain Reaction
Denaturating Gradient Gel Electrophoresis
Lead sponsor: Mlinotest Zivilska Industrija d.d.
Sponsor class: INDUSTRY
Collaborators: name: University of Ljubljana
name: University Medical Centre Ljubljana
First posted: 2014-01-20
Enrollment: 51
Sex: ALL
Minimum age (years): 30
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to investigate if daily consumption of barley beta-glucans effect lipid and glucose metabolism and alter intestinal microbiota composition in participants with metabolic syndrome or with high risk for metabolic syndrome development. It is assumed that 4-week intervention with beta-glucans will improve some clinical signs of metabolic syndrome and alter composition of intestinal microbiota. Variation in microbiota composition will be investigated with emphasis on Bacteroidetes and Firmicutes ratio. Furthermore it is presupposed that consumption of beta-glucans will stimulate growth of beneficial intestinal bacteria from genus Lactobacillus and Bifidobacteria and consequently effect production of short chain fatty acids in population with metabolic syndrome. Moreover it is presupposed that 4-week consumption of beta-glucans will have influence on glucose metabolism and will consequently improve insulin resistance within people with metabolic syndrome or high risk for metabolic syndrome development. It is assumed that 4-week consumption of beta-glucans will improve specific plasma lipid content in population with metabolic syndrome.

Detailed description: In study it will be investigated whether daily consumption of barley beta-glucans integrated in bread product effects lipid and glucose metabolism and alter the composition of intestinal microbiota in a population with metabolic syndrome or with high risk for metabolic syndrome development. 70 participants with metabolic syndrome will be enrolled in study. Participants will daily consume 200 g of bread with high amount of beta-glucans.

Hypothesis:

1. 4- week consumption of beta-glucans alters composition of intestinal microbiota and changes ratio of bacteria from phylum Bacteroidetes and Firmicutes. Furthermore consumption of beta-glucans stimulates growth of beneficial intestinal bacteria from genus Lactobacillus and Bifidobacteria and consequently effects production of short chain fatty acids in population with metabolic syndrome.
2. 4- week consumption of beta-glucans has influence on glucose metabolism and consequently improves insulin resistance within people with metabolic syndrome.
3. 4 - week consumption of beta-glucans improves specific plasma lipid content in population with metabolic syndrome.

Study will be designed as double blind, randomised, placebo controlled clinical trial and performed regarding to CONSORT 2010 recommendations for randomised clinical trials. Patient enrollment will be performed in several community health centres in Slovenia in association with family medicine doctors. Appropriate patients with metabolic syndrome or with high risk for metabolic development will be suggested to participate in clinical trial. Candidates will be suggested to participate in a two month study. If there will not be recruited enough participants for two month study they will be suggested for participation in one month study. Candidates interested in participating in study will be informed about study design and terms and conditions of study by main investigator.

Study will be performed after successful recruitment of first 20 or more participants. Study will be performed three times, so that 70 participants will be recruited in complete study. Participants will consume bread with high beta-glucans content (around 3, 4 g beta-glucans per 100 g of bread) during 8 or 4 week period. Before beginning of study participants will have two week washout period without consuming any pre- and pro-biotics. They will remain their usual eating habits during study period except taking any antibiotics or pre- and pro-biotic. Participants will give blood and stool samples a day before intervention with barley beta-glucans. Blood sampling will involve oral glucose test for insulin resistance determination and sampling for specific lipid content determination. They will also have option to give a blood sample for genetic investigation of genes associated with lipid metabolism (apoE). Blood and stool sampling will be repeated day after intervention period. The same parameters as before intervention period except genetic analysis will be investigated. 72-hour dietary recall will be performed during intervention period individually to evaluate daily nutrient and energetic input of each participant.

Eligibility criteria: Inclusion Criteria are parameters used for metabolic syndrome determination according to International Diabetes Federation (IDF) consensus worldwide definition of Metabolic Syndrome:

Participant must have central obesity: defined as waist circumference ≥ 80 cm for European woman and ≥ 94 cm for European men. Beside central obesity candidates participating in this study must have total cholesterol concentration ≥ 5 mmol/l before entering the study.

Plus any two of the following four factors:

* HDL-cholesterol content: man ≤ 1,03 mmol/, women ≤ 1,23 mmol/l
* Triglycerides content ≥ 1,7 mmol/l
* Fasting blood glucose ≥ 5,6 mmol/l
* Hypertension: systolic blood pressure ≥ 130 mm Hg and diastolic blood pressure ≥ 85 mm Hg

If participant will have diagnosed metabolic syndrome and meet age criteria will be included in study.

Exclusion Criteria:

* Diabetes type II
* Thyroid disorder
* Kidney disorder
* Antibiotic treatment

Primary outcomes:
measure: Total Cholesterol Levels
timeFrame: Baseline outcome measurement
measure: HDL-cholesterol Levels
timeFrame: Baseline measurement
measure: LDL-cholesterol Levels
timeFrame: Baseline measurement
measure: Determination of Composition of Intestinal Microbiota From Fecal Samples
timeFrame: Outcome measurement at baseline
measure: Oral Glucose Tolerance Test (OGTT) for Insulin Resistance Determination (Outcome Measures of Plasma Insulin Concentrations)
timeFrame: OGTT measurements performed before dietary intervention
measure: Oral Glucose Tolerance Test (OGTT) for Insulin Resistance Determination (Outcome Measures of Plasma Glucose Concentrations)
timeFrame: Outcome OGTT measurements performed before dietary intervention
measure: Systolic and Diastolic Blood Pressure
timeFrame: Outcome measurement at baseline.
measure: Determination of Concentration of Short Chain Fatty Acids (SCFA) Present in Fecal Samples
timeFrame: Outcome measurement at baseline
measure: Triglyceride Levels
timeFrame: Outcome measure at baseline.
Secondary outcomes:
measure: Determination of Composition of Intestinal Microbiota From Fecal Samples
timeFrame: Outcome measurement after 4-week dietary intervention
measure: Determination of Concentration of Short Chain Fatty Acids (SCFA) Present in Fecal Samples
timeFrame: Outcome measurement after 4-week dietary intervention
measure: LDL-cholesterol Levels
timeFrame: Outcome measurement after 4-week dietary intervention
measure: HDL-cholesterol Levels
timeFrame: Outcome measurement after 4-week dietary intervention
measure: Triglyceride Levels
timeFrame: Outcome measure after 4-week dietary intervention.
measure: Total Cholesterol Levels
timeFrame: Outcome measurement after 4-week dietary intervention
measure: Oral Glucose Tolerance Test (OGTT) for Insulin Resistance Determination (Outcome Measures of Plasma Glucose Concentrations)
timeFrame: Outcome OGTT measurements performed after 4-week dietary intervention
measure: Oral Glucose Tolerance Test (OGTT) for Insulin Resistance Determination (Outcome Measures of Plasma Insulin Concentrations)
timeFrame: Outcome OGTT measurements performed after 4-week dietary intervention
Other outcomes:
Locations:
city: Ajdovscina
country: Slovenia
facility: Community Health Center Ajdovscina
city: Ljubljana
country: Slovenia
facility: Community Healt Center Ljubljana
city: Postojna
country: Slovenia
facility: Community Health Center Franca Amrozica Postojna
Study officials:
affiliation: Mlinotest d.d. Zivilska Industrija
name: Ana Velikonja, PhD student
role: PRINCIPAL_INVESTIGATOR
affiliation: University Medical Centre Ljubljana
name: Rok Orel, M.D., D.Sc.
role: STUDY_DIRECTOR
affiliation: University of Ljubljana
name: Gorazd Avgustin, UP
role: STUDY_DIRECTOR
References:
citation: (1) Izydorczyk MS,Dexter JE. Barley beta-glucans and arabinoxylans: Molecular structure, physicochemical properties, and uses in food products-a Review. Food Research International 41: 850-868, 2008