An interventional study of Blueberry Powder and Placebo Powder in Menopause, Elevated Blood Pressure and Hypertension, sponsored by Colorado State University. Completed at 1 site in United States. Open to female participants aged 45 Years to 65 Years. Per ClinicalTrials.gov, last updated 2022-09-14.
Sponsored by Colorado State University · Not applicable, Interventional, and Treatment
Postmenopausal women are at an increased risk of developing cardiovascular disease (CVD) largely due to accelerated aging-related modifications to vascular health following menopause. The vascular endothelium is responsible for producing chemicals that are essential for proper vasodilation and blood flow and therefore is involved in maintaining normal blood pressure. A major modification that occurs during aging and is accelerated during menopause is termed vascular endothelial dysfunction which is characterized by impaired endothelium-dependent dilation. This can lead to increased blood pressure, atherosclerosis, and increased risk of CVD and death. Nitric oxide (NO) is a chemical produced by the endothelium and is essential for normal endothelial function and cardiovascular health. Vascular endothelial dysfunction is primarily caused by reduced NO bioavailability secondary to excessive oxidative stress. Approximately 3/4 of postmenopausal women have elevated blood pressure or hypertension which further worsens endothelial function and increases CVD risk through increased oxidative stress and inflammation. Blueberries are rich in phytochemicals including anthocyanins, phenolic acids, and pterostilbene. These phytochemicals and their metabolites are known to attenuate oxidative stress and inflammation. The overall goal of the current study is to assess the efficacy of blueberries to improve vascular endothelial dysfunction in this high-risk population and to gain insight into underlying mechanisms. 58 postmenopausal women with elevated blood pressure and stage 1-HTN will be asked to consume 22 grams freeze-dried blueberry powder or placebo powder per day for 12 weeks. Vascular endothelial function will be assessed at baseline and 12 weeks. Measurements indicative of vascular nitric oxide production, oxidative stress, inflammation, cardiometabolic health, cognitive function, and blueberry phytochemical metabolism will be measured at baseline and 12 weeks. Blood pressure will be assessed at baseline and 4, 8, and 12 weeks.
Exclusion Criteria:
22 g/day freeze-dried blueberry powder for 12 weeks
Dietary Supplement: Blueberry Powder
22 g/day placebo powder for 12 weeks
Dietary Supplement: Placebo Powder
22 g/day freeze-dried blueberry powder for 12 weeks
22 g/day placebo powder for 12 weeks
Endothelium-dependent dilation
Assessed as brachial artery flow-mediated dilation in a study subset of participants
Time frame: Baseline to 12 Weeks
Blood pressure
Assessed using an automated blood pressure monitor (SphgmoCor)
Time frame: Baseline to 12 weeks
Vascular oxidative stress
Change in brachial artery flow-mediated dilation following acute infusion of ascorbic acid (a dose known to scavenge superoxide) as an index of vascular oxidative stress in a study subset of participants
Time frame: Baseline and 12 weeks
Endothelial cell nitric oxide production, oxidative stress, and inflammation
Protein expression markers will be measured by quantitative immunofluorescence in biopsied venous endothelial cells in a study subset of participants
Time frame: Baseline and 12 weeks
Systemic markers of cardiometabolic health
Circulating markers of lipid and glucose metabolism, nitric oxide, and inflammation
Time frame: Baseline and 12 weeks
Plasma blueberry polyphenol metabolites
Targeted analysis of plasma metabolites by GC-MS and LC-MS
Time frame: Baseline and 12 weeks
Endothelium-independent dilation
Assessed as brachial artery diameter responses to sublingual nitroglycerin in a study subset of participants
Time frame: Baseline to 12 weeks
Augmentation index
Arterial stiffness assessed as augmentation index using the SphygmoCor XCEL
Time frame: Baseline to 12 weeks
Pulse wave velocity
Arterial stiffness assessed as carotid-femoral pulse wave velocity using the SphygmoCor XCEL
Time frame: Baseline to 12 weeks
Gut microbiota
Determine the effects on stool sample microbial populations
Time frame: Baseline to 12 weeks
Processing speed
Exploratory measures assessed using the NIH Cognitive Toolbox iPad app
Time frame: Baseline and 12 weeks
Language
Exploratory measures assessed using the NIH Cognitive Toolbox iPad app
Time frame: Baseline and 12 weeks
Working memory
Exploratory measures assessed using the NIH Cognitive Toolbox iPad app
Time frame: Baseline and 12 weeks
Executive function and attention
Exploratory measures assessed using the NIH Cognitive Toolbox iPad app
Time frame: Baseline and 12 weeks
Episodic memory
Exploratory measures assessed using the NIH Cognitive Toolbox iPad app
Time frame: Baseline and 12 weeks
Peripheral blood mononuclear cell inflammation and oxidative stress
Exploratory measures analyzed by gene expression
Time frame: Baseline and 12 weeks
Plan to share: No
This study is completed, as verified in Sep 2022. You cannot join it, but the record below documents what was studied.
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Colorado State University