Effects of Dietary Antioxidants to Prevent Cardiovascular Disease
Condition: Hypercholesterolemia; Healthy
MeSH terms: Hypercholesterolemia
Study type: Interventional
Phase: Phase 2

Summary: 
      Background & Aims: The role of red wine in cardiovascular risk prevention has been documented
      by several epidemiological studies in patients and normocholesterolemic healthy individuals.
      However, it is unclear whether hypercholesterolemic individuals free of cardiovascular
      disease would equally benefit from moderate red wine consumption to prevent atherosclerosis
      and the development of cardiovascular disease.

      Methods: Forty (40) healthy volunteers males and females were recruited, divided into 2
      age-adjusted groups according to their total cholesterol levels; in asymptomatic
      hypercholesterolemics (AHC ), and normocholesterolemics (NC ). Total Antioxidant Capacity
      (TAC ), Lipid profile, Vitamin E, and cardiovascular risk indexes ( LDL /HDL and Vitamin E/TC
      ) were evaluated in the blood serum of all subjects prior to and 1 month after once daily red
      wine consumption as well as prior to and after being given a placebo drink following a 1
      month wash out period and resveratrol for 1 month after wash out period..
    

Detailed description: 
      Study design and measurements This study is a cross-over field trial. Participants were asked
      to consume a specific variety of red wine "tannat" daily in their diet for one month. After a
      wash-out period of one month, the same participants were asked to consume a placebo drink
      daily for another month. Quantitative measurements of blood lipids, vitamin E, and Total
      Antioxidant Capacity before and after consumption of wine and placebo were measured. The
      study aimed to investigate whether consumption of red wine is associated with any changes in
      the levels of blood lipids, vitamin E, and Total Antioxidant Capacity and whether such
      changes - if any -equally occur in hypercholesterolemic individuals.

      Participants were advised to abstain from consuming antioxidant supplements, antioxidant-rich
      foods (including deep-colored fruits and vegetables such as berries, tomatoes, carrots,
      broccoli, apples and plums, green tea, caffeine and chocolate), caffeine and alcohol 2 weeks
      prior to the beginning of initial measurements and during the 3-month experimental period.
      Participants (occasional alcohol drinkers) included in the study received no monetary
      compensation. According to the U.S. Department of Agriculture 2010 Dietary Guidelines,
      moderate drinking corresponds to one drink per day for women and two for men14. Consequently,
      female subjects were given 5 bottles of red wine for 1 month (1 glass per day), and male
      subjects were given 10 bottles (2 glasses/per day) and instructed to report any side effects
      or failure to participate. The single grape variety of Tannat, from a location in Northern
      Greece, was selected among several varieties of red wine for its content in phenolic
      compounds and high antioxidant gradient when tested in vitro. Participants were encouraged to
      not alter their dietary habits or physical activity level during the study. To verify their
      compliance with the instructions provided, we interviewed them before and after the
      experiment, and we also measured the quantity of wine used. One day prior to the beginning of
      the intervention, participants underwent physical and routine biochemical examinations and
      completed two questionnaires, one related to their health status and the other to their
      characteristics. To confirm protocol adherence, a team of colleagues contacted the
      participants by telephone every 2nd day and they visited the clinic to obtain 1 bottle of
      wine and answered a questionnaire regarding their adherence with the protocol requirements.

      For each subject, measurements of serum TAC and vitamin E were performed pre and post 1 month
      of red wine ingestion and pre and post placebo drink ingestion after a 1 month wash out
      period. For vitamin E measurements, fasting subjects were requested to abstain from alcohol
      for 24 hours prior to the blood draw. Serum levels of Total Cholesterol (TC), triglycerides
      (TG), HDL-cholesterol, and LDL-cholesterol were also measured by enzymatic methods. For serum
      HDL-cholesterol levels, fasting blood was collected in tubes with a clot activator and was
      determined enzymatically.

      For the assessment of cardiovascular risk, pre and post red wine consumption ratios
      (LDL/HDL-cholesterol and vitamin E/TC) were calculated. TG/HDL-cholesterol, a marker for
      insulin resistance, was also proposed as a surrogate marker of cardiovascular risk
      assessment. TC/HDL and LDL/HDL are also considered to be strong predictors of the degree of
      clinical benefit from lipid-lowering interventions.
    

Intervention name(s): red wine; resveratrol; placebo
Intervention type(s): Dietary Supplement; Dietary Supplement; Other
Intervention description(s): the individuals were given red wine to consume for 1 month then a wash out period of 1 month; the individuals were given resveratrol for 1 month and then 1 month wash out period; the individuals were given placebo for 1 month
Intervention MeSH terms: Resveratrol
Allocation: Non-Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Asymptomatic hypercholesterolemia,; cardiovascular risk,; total antioxidant capacity; red wine polyphenol content; vitamin E.; resveratrol