Norbixin, a carotenoid found in B. orellana, exhibits various biological activities including binding to the peroxisome proliferator-activated receptor gamma (PPARgamma) with a Ki of 1.15 microM in a cell-free assay. At a dosage of 47.7 mg/kg, norbixin effectively alleviates hyperglycemia, hyperinsulinemia, and insulin resistance, in addition to reducing serum lipid levels, cardiac thiobarbituric acid reactive substances (TBARS), and glutathione (GSH) in rat cardio-metabolic syndrome models. It also lowers serum levels of oxidized LDL, aortic protein oxidation, and the atherosclerotic area in a rabbit cholesterol-induced atherosclerosis model. Furthermore, norbixin, administered at 0.1 and 1 mg/kg per day, minimizes mercury-induced DNA damage in rat hepatocytes and leukocytes and prevents photoreceptor degeneration in an Abca4-/- Rdh8-/- mouse model of age-related macular degeneration (AMD).
