Research advance on the important role of selenoprotein in human health

ABSTRACT

Selenium (Se) is an essential trace element for animal and human health. Se deficiency and Se excessive intake can lead to severe symptoms and are related to diseases. Se is mainly combined with protein in the form of selenocysteine (Sec) and selenomethionine (Se-Met) in the human body. Generally, proteins formed by incorporating Sec into them are called selenoproteins, while proteins bound in other forms are called Se-containing proteins. Selenoprotein is the main form of Se to exert its biological functions in the human body, and Se deficiency could reduce the content and activity of selenoproteins and disturb the normal physiological function. Researches on the relationship between selenoproteins and human health have received increasing attention, and a comprehensive understanding of the function of selenoproteins is helpful to explain the effects of Se on human health. Although the functions of selenoproteins are not yet fully understood, the critical role of many selenoproteins in human health has been revealed increasingly. So far, 25 kinds of selenoproteins have been found in the human body, and this review focuses on the structure and biological function of glutathione peroxidase (GPX), thioredoxin reductase (TrxR) and iodothyronine deiodinase (ID) families and their relationship with diseases. It shows that selenoproteins such as GPX, TrxR and ID families have biological functions of regulating cell oxidative stress, endoplasmic reticulum stress, antioxidant defense, immune response and inflammatory response. The single nucleotide polymorphism (SNP) and DNA methylation in the promoter region of selenoprotein are related to the risk of diseases. Selenoproteins play a vital role in the pathogenesis and prevention of diseases such as tumors, cardiovascular diseases, osteoarthritis (OA), Keshan disease (KSD), Kashin-Beck disease (KBD), and corona virus disease 2019 (COVID-19) through their genetic and epigenetic forms. This research will provide clues and basis for further revealing the role of Se and selenoprotein in human health and screening to prevent disease targets. However, due to the complexity and unknown biological functions of selenoproteins, the mechanism of selenoproteins in resisting diseases and promoting human health is still worthy of further exploration and research.