The Impact of Inorganic Nitrate-rich Beetroot Juice on Microvascular Blood Flow and Cognitive Function

NCT05810974 | Completed

• 1 other identifier: -TBC-
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Cardiovascular disease (CVD) is one of the leading causes of mortality worldwide. Inorganic nitrate found in beetroot and green leafy vegetables has been demonstrated to reduce cardiovascular disease risk factors including reducing blood pressure and the stiffness of blood vessels by increasing levels of a compound called nitric oxide. Much of the research to date has focused on the large blood vessels, and little is known about the impact of inorganic nitrate on smaller blood vessels which could be related to cognitive function. The majority of beneficial effects with inorganic nitrate have been observed within young healthy populations. However, it is known that after the menopause women are at an increased risk of cardiovascular disease and have reduced levels of nitric oxide in their body; this could also contribute to the cognitive decline also observed post-menopause. This trial will investigate the impact of inorganic nitrate from beetroot juice on the blood flow in small blood vessels and on cognitive function in postmenopausal women. The hypothesis of the study is that the nitrate in beetroot juice will increase circulating nitric oxide that will then increase blood flow in small blood vessels and improve cognitive function.

Conditions

Post Menopausal

Keywords

Beetroot; NO; Nitrate; Microvascular function; Cognition

Outcome Measures

Primary Outcomes (5)

• Change from baseline endothelial dependent microvascular function as laser Doppler imaging (LDI) with iontophoresis

  Measurements will be taken by LDI with iontophoresis of endothelium-dependent (acetylcholine (ACh))

  At baseline (t= 0.5 hours) and t= 3 hours

• Change from baseline endothelial independent microvascular function as laser Doppler imaging (LDI) with iontophoresis

  Measurements will be taken by LDI of endothelium-independent (sodium nitroprusside (SNP))

  At baseline (t= 0.5 hours) and t= 3 hours

• Change from baseline cognitive function. Domain: Episodic memory

  -Rey Auditory Verbal Learning Test (RAVLT) task Cognitive domains will be assessed by using the Gorilla online research tools.

  At baseline (t= 0 hours) and t=2.5 hours

• Change from baseline cognitive function. Domain: Executive function 1

  -Digit Span Task

  At baseline (t= 0 hours) and t=2.5 hours

• Change from baseline cognitive function. Domain: Executive function 2

  -Stroop Task

  At baseline (t= 0 hours) and t=2.5 hours

Secondary Outcomes (1)

• Change in blood pressure

  [Time Frame: At baseline (t= 0 hours) and 15 minute intervals until t= 2.5 hours.]

Study Arms (3)

Concentrated beetroot juice

ACTIVE COMPARATOR

Dietary Supplement: Concentrated beetroot juice

Nitrate depleted beetroot juice + potassium nitrate (KNO3)

ACTIVE COMPARATOR

Dietary Supplement: Nitrate depleted beetroot juice + potassium nitrate (KNO3)

Nitrate-depleted beetroot juice

PLACEBO COMPARATOR

Dietary Supplement: Nitrate depleted beetroot juice

Interventions

Concentrated beetroot juice DIETARY_SUPPLEMENT

Subjects will consume 70ml shot (Beet-it Sport nitrate 400 shot, James White Drinks) and this drink contains 0.4g inorganic nitrate

Concentrated beetroot juice

Nitrate depleted beetroot juice + potassium nitrate (KNO3) DIETARY_SUPPLEMENT

Nitrate-depleted beetroot juice (70ml) and 0.4g KNO3- will be mixed. (Same appearance and taste with Beet-it sport shot)

Nitrate depleted beetroot juice + potassium nitrate (KNO3)

Nitrate depleted beetroot juice DIETARY_SUPPLEMENT

Subjects will consume 70ml of (Beet-it Placebo shot, James White Drinks). This drink is the same as the Beet-it Sport nitrate shot but has the nitrate removed.

Nitrate-depleted beetroot juice

Eligibility Criteria

• Age: 45 Years+
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Apparently healthy post-menopausal women (age over 45)
• Able to understand information sheet and willing to comply with the study protocol and able to give informed consent
• Not having menstrual period for 12 months

You may not qualify if:

• Blood pressure \<90/60 or \> 140/90 mmHg
• Medical history of myocardial infarction, angina, thrombosis, stroke, cancer, high cholesterol, liver, renal, respiratory or bowel diseases or diabetes or other endocrine disorder
• BMI\>30
• Any tobacco and/or nicotine users (or quit within the last 6 months)
• Current use of antihypertensive medication
• Alcohol intake \> 14 units/week
• Vigorous exercise \> 3 times/ week
• Antihypertensive medication users
• People who have had hysterectomy
• Currently taking hormone replacement therapy or selective oestrogen receptor modulator

Sponsors & Collaborators

• University of Reading: lead

Study Sites (1)

University of Reading

Reading, UK, RG6 6AH, United Kingdom

Location

MeSH Terms

Interventions

potassium nitrate

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Lecturer, Principal investigator

Study Record Dates

• First Submitted: February 8, 2023
• First Posted: April 13, 2023
• Study Start: March 14, 2023
• Primary Completion: July 7, 2023
• Study Completion: August 7, 2023
• Last Updated: November 22, 2024

Record last verified: 2023-04

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)