Can carotenoids cure or protect us?

Abstract

Introduction: Carotenoids are liposoluble plant pigments. The most common in the human diet are a-carotene, b-carotene, b-cryptoxanthin, lycopene, lutein, and zeaxanthin. Methods: This article provides an overview of the findings on carotenoids to date, their depots in body, recommended daily doses and mechanisms of protective action. We searched PubMed, Google Scholar, SCIndex, Dimension, Scopus and Google for English and Serbian language abstracts, using the searching terms "carotenoids", "provitamin A", "antioxidants", "cardiotoxcity", "prevention" and "NADES". Topic: After being metabolised in intestinal mucosa (with the help of bile acids) and absorbed, carotenoids are mainly stored in the liver and adipose tissue. Major impact on carotenoids bioavailability is the nature of matrix/medium in which they are dissolved. The latest generation of non-toxic "green" solvents, the so-called NADES (natural deep eutectic solvents) are in special focus of research today. Lycopene has been confirmed to improve sperm efficiency, raising incidence of pregnancy. Regarding cardiovascular diseases, trans forms inhibit process of atherosclerosis, most likely by increasing HDL levels. Low serum b-carotene and b-cryptoxanthin concentrations is associated with increased mortality from heart diseases, but also stroke. Carotenoids also can cause apoptosis in TE1 cells of squamous cell carcinoma of the esophagus. The recommended daily doses are still not standardized, due to lack of studies performed. A group of provitamin A carotenoids, when converted to vitamin A, participate in the regulation of vision and prevention of eye diseases (xerophthalmia, macular degeneration, night blindness, ulcerations, scars). They are also associated with potential influences on reproduction, embryogenesis, immune system, intracellular connections as well as metabolic pathways. Studies indicate their influence in the prevention and treatment of cardiovascular diseases, but also various malignancies. Conclusion: The literature data so far has indicated that carotenoids are a good choice in the prevention and treatment of various diseases, however, they are still insufficiently researched to deffine preventive and/or therapeutic doses.