Historical Roles of Selenium and Selenoproteins in Health and Development: The Good, the Bad and the Ugly

Abstract

Selenium is a fascinating element that has a long history, most of which documents it as a deleterious element to health. In more recent years, selenium has been found to be an essential element in the diet of humans, all other mammals, and many other life forms. It has many health benefits that include, for example, roles in preventing heart disease and certain forms of cancer, slowing AIDS progression in HIV patients, supporting male reproduction, inhibiting viral expression, and boosting the immune system, and it also plays essential roles in mammalian development. Elucidating the molecular biology of selenium over the past 40 years generated an entirely new field of science which encompassed the many novel features of selenium. These features were (1) how this element makes its way into protein as the 21st amino acid in the genetic code, selenocysteine (Sec); (2) the vast amount of machinery dedicated to synthesizing Sec uniquely on its tRNA; (3) the incorporation of Sec into protein; and (4) the roles of the resulting Sec-containing proteins (selenoproteins) in health and development. One of the research areas receiving the most attention regarding selenium in health has been its role in cancer prevention, but further research has also exposed the role of this element as a facilitator of various maladies, including cancer.

Selenium, TGF-Beta and Infectious Endemic Cardiopathy: Lessons from Benchwork to Clinical Application in Chagas Disease

“…Selenium (Se) is a nutritional essential trace element relevant to some myocardiopathies [10,11], a condition that was first depicted in studies concerning Keshan cardiomyopathy. This cardiopathy is related to endemic Se nutritional deficiency in Chinese regions where the soil is especially poor in Se, and consequently vegetable foods and animal nutrition are insufficient in Se [11].…”

“…Considering the geographical differences in serum Se observed in our first study [23] in healthy persons (mean 72 mcg/L on Rio de Janeiro and 55 mcg/L in Belo Horizonte) and in severe CD patients (65 mcg/L in Rio de Janeiro and 35 mcg/L in Belo Horizonte), as well as the large differences observed in Se levels in diets from diverse Brazilian regions [55], that varied 100 times from one state to the other (e.g., beans in Ceará have 1.2 mcg of Se/g; in São Paulo, 0.016 mcg of Se/g), it is important to explore Se levels in CD patients at different geographical regions, both in Brazil and in other Latin American countries. However, it is difficult to associate low Se serum levels as a cause or a marker (effect) in CCC progression, since the high inflammatory and oxidative stress in severe CCC [35][36][37] would both require and consume selenoproteins [10,18,56].…”

Selenium as an important factor in various disease states - a review

“…During subsequent studies, it was found that the sediment contained a new, previously unknown compound with properties similar to tellurium. Referring to the similar properties of tellurium, whose Greek name means Earth (Tellus), selenium was given the name meaning the Moon (Tsuji et al, 2021[ 67 ]). Scientists became interested in selenium when it was discovered in the 1950s that increased selenium accumulation causes muscular dystrophy, and a deficiency of this element and vitamin E causes acute liver necrosis in studied rats (Duntas and Benvenga, 2015[ 15 ]).…”

Discriminative Long-Distance Transport of Selenate and Selenite Triggers Glutathione Oxidation in Specific Subcellular Compartments of Root and Shoot Cells in Arabidopsis

“…In mammals, 25 seleno-proteins are known many of which have crucial functions, especially in stress responses (Lu and Holmgren, 2009). Hence, the health-promoting properties of Se have been highlighted in numerous studies (Finley et al, 2001;Tsuji et al, 2021). Se deficiency causes hypothyroidism and increases the risk for diseases of the cardiovascular, osseus and nervous systems (Rayman, 2000).…”