Atherosclerosis, Oxidative Stress
Conditions
Keywords
Carotenoid, LDL oxidation, Cardiovascular disease, Antioxidant
Brief summary
Low-density lipoprotein (LDL) oxidation has a pivotal role in atherosclerosis development. There is a relationship between carotenoids serum concentration and cardiovascular (CV) benefits, mainly in oxidized LDL (oxLDL) reduction. Despite cardio protective effects of annatto carotenoids, bixin and norbixin, in vitro and in animal studies, its short or long-term supplementation effect on humans are not know. Objective: To analyse CV benefits of annatto carotenoids short-term supplementation in healthy individuals, comparing to lycopene effect. Methods: 16 healthy volunteers (8 men and 8 women) consumed 0.05 mg/kg b.w. of each treatment (bixin, norbixin, lycopene or placebo) through capsules, during 7 days. It was analysed the susceptibility of LDL to Cu2+-induced oxidation, biochemical parameters and oxidative stress biomarkers at the beginning and end of each treatment.
Detailed description
Graduate and post-graduate students were recruited in Federal University of Santa Maria to study participation. First, the health status of volunteers was analysed by questioner application (to evaluate lifestyle, family history, individual characteristics), anthropometric (height, weight, waist circumference) and biochemical parameters (glucose, lipid profile, transaminases, urea, creatinine) measurements. According to inclusion criteria, 18 volunteers were able to study participation, but just 16 people remained until the end of the study. Each treatment was composed by 7 capsules (containing 0.05 mg carotenoid or placebo/kg b.w.) which should be consumed once a day (preferably in the morning), during 7 days. It was conducted a randomized, double blind, placebo-controlled crossover clinical trial, where 16 participants received 4 proposed treatments (bixin, norbixin, lycopene and placebo) in different periods. To plasma, serum and red blood cells (RBC) obtainment, 2 fasting blood collections were made, in the beginning (Day 0) and the end (Day 7) of each treatment. These samples were used for evaluating the ex vivo oxidation of LDL induced by copper sulphate and biochemical and oxidative biomarkers measurements.
Interventions
DIETARY_SUPPLEMENTBixin
Volunteers consumed bixin capsules during 1 week , maintaining their usal lifestyle (avoiding excessive/unusual of fat and carotenoid-containing food, alcohol)
DIETARY_SUPPLEMENTNorbixin
Volunteers consumed norbixin capsules during 1 week , maintaining their usal lifestyle (avoiding excessive/unusual of fat and carotenoid-containing food, alcohol)
DIETARY_SUPPLEMENTLycopene
Volunteers consumed lycopene capsules during 1 week , maintaining their usal lifestyle (avoiding excessive/unusual of fat and carotenoid-containing food, alcohol)
DIETARY_SUPPLEMENTPlacebo
Volunteers consumed placebo capsules during 1 week , maintaining their usal lifestyle (avoiding excessive/unusual of fat and carotenoid-containing food, alcohol)
Sponsors
Universidade Federal de Santa Maria
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Investigator)
Masking description
Double blind
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Normal levels of glucose, lipid profile, transaminases, urea and creatine * Normal blood pressure, weight and body mass index (BMI)
Exclusion criteria
* Chronic diseases (diabetes, dyslipiademia, hypertension cancer, etc.) * Drug, alcohol and cigarette consumption/addiction * Medication, vitamins or suplements consumption (except oral contraceptive used by women) * Recent inflammatory/infectious diseases
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Evaluation of LDL lipid moiety susceptibility to copper induced oxidation - oxidation rate | Day 0 and Day 7 | Change (Day 7 - Day 0) of oxidation rate of conjugated dienes formed after copper sulphate addition to LDL particles |
| Evaluation of LDL protein moiety susceptibility to copper induced oxidation | Day 0 and Day 7 | Evaluate the change (Day 7 - Day 0) of loss of tryptophan fluorescence after oxidation induced by copper |
| Evaluation of LDL lipid moiety susceptibility to copper induced oxidation - lag phase | Day 0 and Day 7 | Change (Day 7 - Day 0) of lag phase time of conjugated dienes formed after copper sulphate addition to LDL particles |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Evaluation of nitric oxide metabolites | Day 0 and Day 7 | Change at nitric oxide metabolites levels in serum |
| Evaluation of plasma antioxidant capacity | Day 0 and Day 7 | Change at oxygen radical absorbance capacity in plasma |
| Evaluation of enzymatic antioxidant defences | Day 0 and Day 7 | Change at antioxidant enzymes activities in red blood cells |
| Evaluation of red blood cell osmotic fragility | Day 7 | Change of red blood cell osmotic fragility after ex vivo exposure to membrane damage inducers |
| Evaluation of carotenoids levels | Day 0 and Day 7 | Change at carotenoids levels in plasma and red blood cells |
| Evaluation of gluthatione cycle | Day 0 and Day 7 | Change at reduced glutathione/oxidized glutathione ratio in red blood cells |
| Evaluation of protein oxidation | Day 0 and Day 7 | Change at advanced oxidation protein products levels in plasma |
| Evaluation of lipid oxidation | Day 0 and Day 7 | Change at malondialdehyde levels in plasma and red blood cells |
Countries
Brazil
Outcome results
None listed