Intervention With Riboflavin to Improve Vascular Health and ENdothelial Functioning in Genetically at- Risk Adults

Not Applicable

• Conditions: Blood Pressure; Hypertension
• Interventions: Dietary Supplement: Placebo; Dietary Supplement: Riboflavin 1.6mg/d; Dietary Supplement: Riboflavin 5mg/d; Dietary Supplement: Riboflavin 20mg/d

• Registration Number: NCT05488106
• Lead Sponsor: University of Ulster

Brief Summary

High blood pressure is the leading risk factor for heart disease and stroke. Approximately 12% of the population have a particular genetic factor (known as the TT genotype) which increases the risk of high blood pressure. Previous studies conducted at this centre have shown that taking the B-vitamin riboflavin, for up to 3 months, decreases blood pressure in adults with the TT genotype. It is currently not known how riboflavin lowers blood pressure in those with the TT genotype but it could be as a result of altering blood levels of nitric oxide. Nitric oxide causes blood vessels to expand, leading to improved blood vessel function, an important predictor of cardiovascular health. However, the effect of riboflavin supplementation on nitric oxide and blood vessel function has not been previously studied. Furthermore, it is unclear whether taking riboflavin over a shorter period of time or at doses higher than 1.6 mg/d can also lower blood pressure and improve blood vessel function in this at risk group. Therefore, the aim of this study is to assess the effects of riboflavin supplementation on blood pressure, biomarkers of nitric oxide bioavailability and blood vessel function. It is hypothesised that riboflavin supplementation will increase nitric oxide bioavailability, leading to reduced blood pressure and improved blood vessel function and, and that a higher riboflavin dose will lead to greater reductions in blood pressure.

Detailed Description

Not available

Study Timeline

• Status Verified: 2022-08
• Study First Submitted: 2022-08-02
• Study First Submitted QC: 2022-08-02
• Study First Posted: 2022-08-04
• Last Update Submitted: 2022-08-04
• Last Update Posted: 2022-08-09
• Study Start: 2022-09-01
• Primary Completion: 2023-06-30
• Study Completion: 2023-06-30

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Male
• Target Recruitment: 120

Inclusion Criteria

• Male
• Aged 60 years and below
• Pre-screened for MTHFR 677TT genotype (TTs and CCs individuals only invited)

Exclusion Criteria

• Consumer of B-vitamin supplements
• Consuming medication that interferes with B-vitamin metabolism

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	-
Dose 1	Riboflavin 1.6mg/d	-
Dose 2	Riboflavin 5mg/d	-
Dose 3	Riboflavin 20mg/d	-

Primary Outcome Measures

Name	Time	Method
Diastolic blood pressure	Change over 16 weeks	Branchial blood pressure
Systolic blood pressure	Change over 16 weeks	Branchial blood pressure

Secondary Outcome Measures

Name	Time	Method
Endothelial function	Change over 16 weeks	Measured by Flow Mediated Dilation
Erythrocyte glutathione reductase activation coefficient (EGRac)(Vitamin B2 marker)	Change over 16 weeks	Measured on automatic analyser
Nitric oxide bioavailability	Change over 16 weeks	Plasma nitrite and nitrate oxide analysed by a Sievers gas-phase chemiluminescence nitric oxide analyser
Pyridoxal phosphate (Vitamin B6 marker)	Change over 16 weeks	Measured on HPLC

Trial Locations

Locations (1)

Human Intervention Studies Unit, Ulster University; 🇬🇧 Coleraine, Co.Londonderry, United Kingdom