Clinical trial NCT03266055: Effects of Blueberry on Gut Microbiota and Metabolic Syndrome
Official title: Prebiotic Effects of Blueberry in Overweight/Obese Individuals: Potential Role of the Gut Microbiota in Alleviating the Metabolic Syndrome.
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Gut Microbiota
Metabolic Syndrome
Keywords: Blueberry
Diet
Lead sponsor: Laval University
Sponsor class: OTHER
First posted: 2017-08-29
Enrollment: 59
Sex: ALL
Minimum age (years): 18
Maximum age (years): 55
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: There is growing evidence that nutritional intervention with dietary polyphenols can positively modulate the gut microbiota to improve cardiometabolic health. Whether the beneficial effects of blueberries on obesity and the metabolic syndrome can be linked to their potential impact on the gut microbiota and intestinal integrity remains speculative at this time. Moreover, the mechanisms of action underlying health benefits associated to blueberry consumption are still unknown. The investigators are thus proposing to combine the study of metagenomics, transcriptomics and metabolomics to test whether a prebiotic activity of highbush blueberries can play a role in the prevention of obesity-linked metabolic syndrome in a clinical setting.


Eligibility criteria: Inclusion Criteria:

* Men and premenopause women in good health
* Caucasians
* At least one of the following : BMI between 25 and 40 kg/m2 or Waist circumference ≥ 80 cm for women and ≥ 94 cm for men
* At least one of the following : TG ≥ 1.35 mmol/L or fasting insulinemia ≥ 42 pmol/L

Exclusion Criteria:

* Metabolic disorders (hypertension, diabetes, hypercholesterolemia)
* Regular use of medication affecting study parameters
* Use of natural health product in the last 3 months
* Use of antibiotics in the last 3 months
* Nicotine users
* Allergy or intolerance for blueberries
* Blueberry taste aversion
* More than 2 alcohol drinks par day
* Particular dietary habits (vegetarism, gluten-free diet, cetogenic diet...)
* Weight change of more than 5% in the last 3 months
* Surgery in the last 3 months or planed during the study

Primary outcomes:
measure: Changes in plasma insulin/glucose of overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 12 months
measure: Changes in plasma lipids/lipoproteins of overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 12 months
Secondary outcomes:
measure: Changes in gene expression in overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 3-6 months
measure: Changes in metabolites concentration in overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 3-6 months
measure: Changes in the gut microbiota composition in overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 3-6 months
measure: Changes in blood pressure of overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 12 months
measure: Changes in intestinal integrity of overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 12 months
measure: Changes in inflammation biomarkers of overweight/obese men and women taking either blueberry powder or placebo blueberry powder
timeFrame: 12 months
Other outcomes:
Locations:
city: Québec
country: Canada
facility: Laval University
Study officials:
affiliation: Laval University
name: Marie-Claude Vohl
role: PRINCIPAL_INVESTIGATOR
References:
citation: Rousseau M, Horne J, Guenard F, de Toro-Martin J, Garneau V, Guay V, Kearney M, Pilon G, Roy D, Couture P, Couillard C, Marette A, Vohl MC. An 8-week freeze-dried blueberry supplement impacts immune-related pathways: a randomized, double-blind placebo-controlled trial. Genes Nutr. 2021 May 17;16(1):7. doi: 10.1186/s12263-021-00688-2.