Selenium Biochemistry and Health Implications

Selenium is an essential trace element that underpins a diverse array of biochemical processes through its incorporation as the amino acid selenocysteine into a family of selenoproteins. These proteins act predominantly in redox regulation, antioxidant defence and thyroid hormone metabolism, thereby influencing immune competence, reproduction, neurological function and metabolic homeostasis. Dietary selenium occurs in organic forms such as selenomethionine and selenocysteine, as well as inorganic forms including selenite and selenate. Following intestinal absorption, selenium is directed to the liver for synthesis of selenoprotein P, the principal transporter to peripheral tissues. Adequate selenium status supports glutathione peroxidases and thioredoxin reductases in scavenging reactive oxygen species, while dysregulation may contribute to chronic inflammation, cardiovascular disease, cancer and neurodegeneration. Both deficiency and excess exhibit a U-shaped relationship with adverse outcomes, highlighting the importance of optimising intake within a narrow therapeutic window. Global variations in soil selenium content drive regional differences in dietary supply, necessitating targeted public health measures such as biofortification and tailored supplementation. Emerging evidence also emphasises interactions with other metals, host genetics and the microbiome in shaping selenium metabolism, offering new avenues for personalised nutrition and therapeutic intervention.

Research from Nature Portfolio

Recent studies have elucidated the interplay between copper homeostasis and selenium transport. Excess copper in hepatocytes disrupts the Golgi-mediated secretion of selenoprotein P, leading to intracellular accumulation and reduced release into the circulation. This mechanism sheds light on selenium deficiency observed in conditions of hepatic copper overload and suggests that modulation of metal transport pathways may influence peripheral selenium delivery and antioxidative capacity.

Selenium Biochemistry and Health Implications publication trend

The graph below shows the total number of articles in selenium biochemistry and health implications across all publications each year (not limited to Nature Index journals).

Technical terms

Selenocysteine: The 21st amino acid, containing selenium, incorporated co-translationally into selenoproteins at UGA codons.

Selenoprotein P: A liver-derived glycoprotein that transports selenium via the bloodstream to peripheral organs and tissues.

Redox homeostasis: The maintenance of a balanced state between oxidants and antioxidants crucial for cellular integrity and signalling.

Oxidative stress: A pathophysiological condition arising from excess reactive oxygen species that can damage biomolecules and disrupt function.

References

1. Excessive copper impairs intrahepatocyte trafficking and secretion of selenoprotein P. Nature Communications (2023).
2. Selenium, Selenoproteins, and Immunity. Nutrients (2018).
3. Selenium, Selenoproteins and Viral Infection. Nutrients (2019).
4. Organic selenium compounds as potential chemotherapeutic agents for improved cancer treatment. Free Radical Biology and Medicine (2018).