Clinical trial NCT06735651: Blueberries for Gut, Brain, and Cardiometabolic Health in Prediabetes
Official title: Wild Blueberries for Gut, Brain, and Cardiometabolic Health in Female Adults With Prediabetes.
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Prediabetes (Insulin Resistance, Impaired Glucose Tolerance)
Female
Adult
Endothelial Function (Reactive Hyperemia)
Arterial Stiffness
Cognition
Oxidative Stress
Gut Microbiota
Overweight
Inflammation
Microvascular Function
Body Composition
Keywords: Blueberries
Prediabetes
Insulin Resistance
Functional foods
Dietary intervention
Endothelial function
Vascular function
Cardiovascular health
Metabolic health
Gut microbiota
Cognitive function
Type II diabetes
Microvascular Function
Wild Blueberries
Lead sponsor: Georgia State University
Sponsor class: OTHER
Collaborators: name: Wild Blueberry Association of North America
First posted: 2024-12-16
Enrollment: 30
Sex: FEMALE
Minimum age (years): 45
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The goal of this clinical trial is to determine the effectiveness of using a freeze-dried wild blueberry powder on cardiometabolic health, cognitive function, and gut microbiota composition in adult women with prediabetes.

Detailed description: In the U.S., 35.3 million adults have type 2 diabetes mellitus (T2DM) and 96 million have prediabetes. Eight out of 10 people with T2DM die from cardiovascular disease. People with T2DM also have a 50% higher risk of developing dementia compared to healthy counterparts. Further, studies show that gut microbes play a major role in the development of T2DM. Prevention and treatment of T2DM focus on lifestyle changes including dietary modifications such as increased consumption of deep-colored fruits like berries. Blueberries are rich in fiber and phytochemicals and have several health benefits. We and others have shown that blueberry intake improves heart health in healthy men, hypertensive postmenopausal women, and men and women with metabolic syndrome. Yet, a comprehensive study in women with prediabetes that measures changes in cognitive performance and the underlying heart and gut health has not been conducted to date. Thus, the overall objective of this study is to investigate and bring forth evidence that blueberries improve gut, cardiometabolic, and cognitive function in women with prediabetes.

Therefore, this pilot six-week randomized, placebo-controlled parallel-arm clinical trial aims to investigate whether daily consumption of 22 g of freeze-dried blueberry powder improves gut, cardiometabolic, and cognitive function in women with prediabetes. Investigators hypothesize that daily consumption of blueberries will improve cardiometabolic parameters, gut dysbiosis, and cognitive impairments in our study population. To test these hypotheses, the following specific aims are proposed. To investigate whether daily consumption of 22 g of freeze-dried blueberry powder:

* Reduces levels of fasting blood glucose (FBG), insulin, and HOMA-IR (homeostatic model assessment of insulin resistance) and improves lipid profile in women with prediabetes.
* Reduces blood pressure and improves endothelial function in women with prediabetes.
* Improves cognitive function (verbal memory and executive functions \[inhibition, working memory, cognitive flexibility\]) in women with prediabetes.
* Favorably modulates gut microbiota composition in women with prediabetes.
* Improves serum markers of oxidative stress and inflammation in women with prediabetes.

Additionally, whether changes in the gut microbiota are associated with changes in cardiometabolic and cognitive function outcomes and whether changes in cardiometabolic outcomes are associated with changes in cognitive function parameters will be explored.

Eligibility criteria: Inclusion Criteria:

* Women aged 45-65 years old
* Prediabetes (fasting blood glucose 100-125 mg/dL and/or HbA1c percentage between 5.7-6.4)
* Body Mass Index between 25-30 kg/m\^2

Exclusion Criteria:

* Allergies to berries
* Use of insulin, antidiabetic, antibiotics, and anti-inflammatory drugs
* Active cancer, gastrointestinal, renal, thyroid, stage 1 \& 2 hypertension and other cardiovascular diseases, neurological diseases, or severe head injury
* Smoking
* Consumes greater than 2 alcoholic beverages per day
* Consumes antioxidant, probiotic, and prebiotic supplements
* Pregnant or Lactating
* Actively participating in a weight loss program
* Currently taking berry supplements or recently participated in another study taking berry supplements

Primary outcomes:
measure: Blood Glucose
timeFrame: Baseline and 6 weeks
measure: Ambulatory Blood Pressure
timeFrame: Baseline and 6 weeks
Secondary outcomes:
measure: Fasting Insulin
timeFrame: Baseline and 6 weeks
measure: Homeostasis model assessment-insulin resistance (HOMA-R)
timeFrame: Baseline and 6 weeks
measure: Blood Lipid Profile
timeFrame: Baseline and 6 weeks
measure: Gut Microbiota Composition
timeFrame: Baseline and 6 weeks
measure: Global Cognitive Ability
timeFrame: Screening
measure: Performance Validity
timeFrame: Baseline and 6 weeks
measure: Verbal Memory & Recognition
timeFrame: Baseline and 6 weeks
measure: Cognitive Inhibition
timeFrame: Baseline and 6 weeks
measure: Cognitive Flexibility
timeFrame: Baseline and 6 weeks
measure: Working Memory
timeFrame: Baseline and 6 weeks
measure: Processing Speed
timeFrame: Baseline and 6 weeks
measure: Associative Memory
timeFrame: Baseline and 6 months
measure: Attention
timeFrame: Baseline and 6 weeks
measure: Problem-Solving
timeFrame: Baseline and 6 weeks
Other outcomes:
measure: Reactive Hyperemia Index
timeFrame: Baseline and 6 weeks
measure: Pulse Wave Velocity
timeFrame: Baseline and 6 weeks
measure: Percent Maximal Microvascular Blood Flow
timeFrame: Baseline and 6 weeks
measure: Circulating Markers of Inflammation and Oxidative Stress
timeFrame: Baseline and 6 weeks
measure: Urinary Polyphenolic Metabolites
timeFrame: Baseline and 6 weeks
measure: Body Fat
timeFrame: Baseline and 6 weeks
Locations:
city: Atlanta
country: United States
facility: Georgia State University
state: Georgia
Study officials:
affiliation: Georgia State University
name: Rafaela G Feresin, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Stote KS, Wilson MM, Hallenbeck D, Thomas K, Rourke JM, Sweeney MI, Gottschall-Pass KT, Gosmanov AR. Effect of Blueberry Consumption on Cardiometabolic Health Parameters in Men with Type 2 Diabetes: An 8-Week, Double-Blind, Randomized, Placebo-Controlled Trial. Curr Dev Nutr. 2020 Mar 9;4(4):nzaa030. doi: 10.1093/cdn/nzaa030. eCollection 2020 Apr.
citation: Miller MG, Hamilton DA, Joseph JA, Shukitt-Hale B. Dietary blueberry improves cognition among older adults in a randomized, double-blind, placebo-controlled trial. Eur J Nutr. 2018 Apr;57(3):1169-1180. doi: 10.1007/s00394-017-1400-8. Epub 2017 Mar 10.
citation: Biessels GJ, Despa F. Cognitive decline and dementia in diabetes mellitus: mechanisms and clinical implications. Nat Rev Endocrinol. 2018 Oct;14(10):591-604. doi: 10.1038/s41574-018-0048-7.
citation: Rawshani A, Rawshani A, Franzen S, Eliasson B, Svensson AM, Miftaraj M, McGuire DK, Sattar N, Rosengren A, Gudbjornsdottir S. Mortality and Cardiovascular Disease in Type 1 and Type 2 Diabetes. N Engl J Med. 2017 Apr 13;376(15):1407-1418. doi: 10.1056/NEJMoa1608664.
citation: Krikorian R, Skelton MR, Summer SS, Shidler MD, Sullivan PG. Blueberry Supplementation in Midlife for Dementia Risk Reduction. Nutrients. 2022 Apr 13;14(8):1619. doi: 10.3390/nu14081619.
citation: Johnson SA, Figueroa A, Navaei N, Wong A, Kalfon R, Ormsbee LT, Feresin RG, Elam ML, Hooshmand S, Payton ME, Arjmandi BH. Daily blueberry consumption improves blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension: a randomized, double-blind, placebo-controlled clinical trial. J Acad Nutr Diet. 2015 Mar;115(3):369-377. doi: 10.1016/j.jand.2014.11.001. Epub 2015 Jan 8.