Effect of Betaine, Serine and Folic Acid on Vascular Function in Healthy Volunteers

This study has been completed.
Sponsor:
Information provided by:
Wageningen Centre for Food Sciences
ClinicalTrials.gov Identifier:
NCT00126347
First received: August 2, 2005
Last updated: August 17, 2005
Last verified: August 2005
  Purpose

The purpose of this study is to determine whether reducing the increase in plasma homocysteine concentrations following an oral methionine load affects vascular function in healthy volunteers, irrespective of the homocysteine-lowering agent.


Condition Intervention
Healthy
Cardiovascular Diseases
Procedure: supplementation with betaine, serine, and folic acid

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double-Blind
Primary Purpose: Prevention
Official Title: Effect of Lowering of Plasma Homocysteine Concentrations After an Oral Methionine Load on Vascular Function in Healthy Volunteers

Resource links provided by NLM:


Further study details as provided by Wageningen Centre for Food Sciences:

Primary Outcome Measures:
  • concentrations of plasma homocysteine before and following an oral methionine load
  • vascular function, measured as flow mediated vasodilation before and following an oral methionine load

Secondary Outcome Measures:
  • B-vitamins
  • blood pressure

Estimated Enrollment: 40
Study Start Date: August 2002
Estimated Study Completion Date: July 2003
Detailed Description:

A high plasma homocysteine is a potential risk factor for cardiovascular disease and death. However, it remains uncertain whether homocysteine per se, low status of folate, or other factors related to methionine metabolism are involved in the pathogenesis of cardiovascular disease. Previous studies have shown that a high concentration of homocysteine in blood is related to an impaired vascular function in the arteries, an indicator of cardiovascular disease risk. Virtually all intervention trials used folic acid as a homocysteine-lowering agent, which may however affect vascular function through mechanisms not related to homocysteine. The researchers investigated whether reduction in homocysteine concentrations following a methionine load, via supplementation with serine, betaine or folic acid improves vascular function in healthy volunteers, in order to distinguish between effects of folic acid and of homocysteine-lowering per se.

Comparison: The effects of supplementation with serine, folic acid and betaine (all together with an oral methionine load) were compared to the effects of a placebo (together with a methionine load) on plasma homocysteine concentrations and on vascular function following methionine loading in healthy volunteers.

  Eligibility

Ages Eligible for Study:   50 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Apparently healthy
  • Women postmenopausal: two or more years after last menstruation. If the uterus was surgically removed, the women must be 55 years or older
  • Normal blood values for: hematology, total homocysteine, lipids, vitamin B6, vitamin B12, folic acid, liver enzymes, creatinine
  • Absence of protein and glucose in urine sample
  • Body mass index (BMI) between 18 and 30 kg/m2
  • Good ultrasound visibility of the brachial artery, judged by a sonographer.
  • Willing not to use supplements containing B-vitamins, antioxidant vitamins (A, beta-carotene, C and E) or n-3 fatty acids/fish oil supplements from screening day (>2 months before start of the study) until end of study
  • Willing not to be blood or plasmapherese donor from 4 weeks before the screening day, and 4 weeks before the start of the study until the end of study

Exclusion Criteria:

  • Any chronic or acute disease (e.g. diabetes, renal disease, inflammation)
  • Current, or history of cardiovascular disease
  • Hypertension
  • Medical history or surgical events know to interfere with the study
  • Fasting plasma total homocysteine > 26 micromol/L
  • Alcohol consumption: women >21 consumptions/week; men >28 consumptions/week
  • Weight loss or gain > 2 kg in the month prior to screening
  • Any special diet (prescribed, slimming, macrobiotic or total vegetarian. Sole exclusion of meat and fish from a otherwise ‘normal’ western diet is allowed).
  • Lactose intolerance
  • Use of supplements containing B-vitamins more than once weekly in the period from 3 months before the screening day
  • Participation in any other trial up to 3 months before this study
  • Use of medication known to interfere with the study outcome.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00126347

Locations
Netherlands
Wageningen Centre for Food Sciences
Wageningen, Netherlands
Sponsors and Collaborators
Wageningen Centre for Food Sciences
Investigators
Study Chair: Petra Verhoef, PhD Wageningen Centre for Food Sciences
  More Information

No publications provided

ClinicalTrials.gov Identifier: NCT00126347     History of Changes
Other Study ID Numbers: P02.0470L
Study First Received: August 2, 2005
Last Updated: August 17, 2005
Health Authority: Netherlands: The Central Committee on Research Involving Human Subjects (CCMO)

Keywords provided by Wageningen Centre for Food Sciences:
betaine
serine
folic acid
methionine load
homocysteine
cardiovascular health
vascular function
human

Additional relevant MeSH terms:
Cardiovascular Diseases
Betaine
Folic Acid
Vitamin B Complex
Gastrointestinal Agents
Therapeutic Uses
Pharmacologic Actions
Lipotropic Agents
Hypolipidemic Agents
Antimetabolites
Molecular Mechanisms of Pharmacological Action
Lipid Regulating Agents
Hematinics
Hematologic Agents
Vitamins
Micronutrients
Growth Substances
Physiological Effects of Drugs

ClinicalTrials.gov processed this record on August 28, 2014