Effect of Short-term Annatto Carotenoids Supplementation on Oxidative Stress Status in Healthy Individuals

Overview

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.

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.