Selenium and Biological Function of Selenoprotein in Health and Diseases

Abstract

Selenium is one of the important trace elements with its biological function in human health through over 30 mammalian selenoproteins. Food sources of selenium are bread and cereals, meat, fish and eggs, milk, dairy products and beverage, fruit and vegetables. There are some factors that may regulate selenium contents in food (plants and animals) such as geological conditions, environmental factors, fertilizer with selenium and animal feedstuffs. Individual selenium intakes among populations in different countries are also varied and quantity of human intake reflects selenium status as well as efficacy of biological functions. Selenoproteins include in glutathione peroxidases, iodothyronine deiodinases, thioredoxin reductases, and selenophosphate synthetase. These proteins mostly function in antioxidant system, redox reaction, thyroid hormone metabolism and immune response. Low selenium status can lead to a large number of diseases, including cardiovascular disease, cancer and immune dysfunction. From these evidence, more attempts and researches have been proposed to assess selenium intake, selenium status and related mechanism for health benefit effects.