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

August 2, 2005
August 17, 2005
August 2002
Not Provided
  • 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
Same as current
Complete list of historical versions of study NCT00126347 on ClinicalTrials.gov Archive Site
  • B-vitamins
  • blood pressure
Same as current
Not Provided
Not Provided
 
Effect of Betaine, Serine and Folic Acid on Vascular Function in Healthy Volunteers
Effect of Lowering of Plasma Homocysteine Concentrations After an Oral Methionine Load on Vascular Function in Healthy Volunteers

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.

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.

Interventional
Not Provided
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double-Blind
Primary Purpose: Prevention
  • Healthy
  • Cardiovascular Diseases
Procedure: supplementation with betaine, serine, and folic acid
Not Provided
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*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
40
July 2003
Not Provided

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.
Both
50 Years to 70 Years
Yes
Contact information is only displayed when the study is recruiting subjects
Netherlands
 
NCT00126347
P02.0470L
Not Provided
Not Provided
Wageningen Centre for Food Sciences
Not Provided
Study Chair: Petra Verhoef, PhD Wageningen Centre for Food Sciences
Wageningen Centre for Food Sciences
August 2005

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP