Inorganic Nitrate Supplementation on Cerebrovascular Aging and Arterial Stiffness Study

• Status: Recruiting
• Trial end date: 2023-06-30
• Target enrollment: 0
• Participant gender: All

Summary

This study investigates the effect of dietary inorganic nitrate supplementation on 1) large elastic artery stiffness and hemodynamics and 2) cerebrovascular function in middle-aged and older adults. Participants will be randomized to consume either nitrate-containing or nitrate-depleted beetroot juice.

• Phase: Early Phase 1
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Gary L. Pierce
• Collaborator: University of Wisconsin, Madison

Criteria

Inclusion Criteria:

• Age 50-79 years

• Cognitively healthy, having mild cognitive impairment

• Able to undergo cardiovascular testing procedures including fasting overnight and holding selected morning medication doses.

• Ability to understand and willingness to sign a written informed consent document.

• Ability to lie comfortably for up to 90 minutes

• Women only: Post-menopausal

Exclusion Criteria:

• Current or history of cardiovascular disease disease (heart attack, stroke, heart failure, cardiomyopathy or peripheral artery disease, heart angioplasty/stent or bypass surgery, valve replacement, carotid endarterectomy, heart transplant.

• Medical history of stroke or other neurological disorder or systemic illness that could potentially affect cognition or brain function (outside of a diagnosis of Mild Cognitive impairment, Alzheimer's Disease) or could affect their safety or comfort while undergoing the imaging or cardiovascular studies.

• Subjects with evidence of cardiovascular disease at baseline or during the exercise test (evidence of myocardial infarction, abnormal cardiac arrhythmia, myocardial ischemia, conduction delays, >1mm S-T segment depression or elevation; >3 beat ventricular tachycardia; atrial fibrillation) will be excluded from the study.

• Wilson's disease, hemochromatosis

• Individuals taking clonidine or other short-acting beta blocker

• Resting blood pressure > 200/ 110 mmHg or systolic <90 mmHg

• Medical history of chronic major psychiatric or current diagnosis of major psychiatric disease (other than dementia).

• Systemic illness or neurological disorder potentially affecting cognition or cerebral blood flow other than mild cognitive impairment

• Unable to provide informed consent due to cognitive impairment

• Currently taking medications that may affect cerebral blood flow (e.g. papaverine, indomethacin, acetazolamide, etc) or efficacy of beetroot juice (proton pump inhibitors)

• Current clinically abnormal thyroid function not adequately regulated by thyroid hormone supplementation or medication.

• Allergic to beets

• Current tobacco user or history of tobacco use within the past 3 months (cigarettes, cigars, chewing tobacco, hookah, electronic cigarettes) or living with someone who smokes/has smoked in the past 3 months.

• Current diagnosis of insulin-dependent diabetes (Type I or insulin dependent Type II)

• Current diagnosis of chronic obstructive lung disease, cystic fibrosis, emphysema, chronic bronchitis

• History of renal failure, dialysis or kidney transplant

• Current diagnosis or history of liver disease or HIV/AIDS, or cancer (other than non-melanoma skin cancers).

• Current diagnosis or history of rheumatoid arthritis, systemic lupus erythematosus, Wegener's granulomatosis

• Vulnerable populations (prisoners, etc) will not be eligible.

• Unwillingness to wash out from a vitamin or dietary supplement regime prior to enrollment and maintain throughout the duration of the study.

• Inability to comply with experimental instructions.

• Uncontrolled intercurrent illness that would limit compliance with study requirements per investigator.

• Inability to fast or hold morning medications doses until after testing is complete.

• Hormone replacement use within the past 6 months

• Currently enrolled in another study using an study medication, supplement, device or intervention.