Effects of selenium toxicity and deficiency on humans

Project Abstract

Selenium is an essential trace element that plays a critical role in human health. Both deficiency and toxicity of selenium can have significant impacts on human physiology and health. Selenium deficiency has been linked to various health issues, including compromised immune function, increased risk of chronic diseases such as cancer and heart disease, and impaired cognitive function. On the other hand, selenium toxicity can result in a condition known as selenosis, characterized by symptoms such as hair loss, gastrointestinal disturbances, fatigue, and neurological abnormalities. This research project aims to explore the effects of selenium toxicity and deficiency on humans by investigating the underlying mechanisms involved in these conditions. Through a review of current literature and studies on selenium, the project will examine how selenium levels in the body are regulated, the role of selenium in antioxidant defense mechanisms, and the impact of selenium imbalance on cellular processes. The project will also investigate the sources of selenium in the diet, highlighting the importance of maintaining an optimal selenium intake to prevent both deficiency and toxicity. By analyzing the bioavailability of selenium from different food sources and supplements, the research will provide insights into strategies for achieving adequate selenium levels without exceeding the safe upper limit. Furthermore, the project will explore the geographical distribution of selenium in soil and its impact on the selenium content of crops, as selenium levels in food sources can vary significantly depending on the selenium concentration in the soil. Understanding the factors that influence selenium levels in food is crucial for developing effective strategies to address selenium deficiency in populations at risk. Overall, this research project will contribute to a better understanding of the effects of selenium toxicity and deficiency on human health and provide valuable insights into the importance of maintaining optimal selenium levels for overall well-being. By elucidating the mechanisms involved in selenium-related conditions and exploring strategies for selenium intake optimization, this research aims to inform public health initiatives aimed at addressing selenium imbalances and promoting human health and longevity.

Project Overview

<p> </p><p><strong>INTRODUCTION</strong></p><p><strong>1.1. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</strong><strong>BACKGROUND INFORMATION</strong></p><p>Selenium (Se) is an essential trace element having biological functions of utmost importance for human health. Different from the other (semi) metals, it is incorporated into proteins by a co-translational mechanism as part of the amino acid selenocysteine (SeCys), the 21st amino acid used for protein synthesis in humans, whereas only a few of them have been functionally characterized. Most Se-proteins participate in antioxidant defence and redox state regulation, particularly the families of more specific essential roles, such as iodothyronine deiodinases (DIOs) which are involved in thyroid hormones metabolism, GPx4 which is essential for spermatogenesis, and selenophospathe synthetases 2 (SPS2) participating in Se-protein biosynthesis.</p><p>Other Se-proteins may be involved in important biological processes, but their exact mechanism of action is still yet to be fully understood. Despite the scarce knowledge of the precise biochemical functions, a very large number of studies have been carried out in the last two decades showing that insufficient Se levels, and particularly Se-proteins, are associated with several human diseases including cancer, diabetes, cardiovascular and immune system disorders. In most cases, the link lies in the contrast to the oxidative stress that may be booth causing or caused by the disease. In this context, it is important to decipher whether and adequate Se status may contrast the risk factors for health disorders, or Se supplementation may improve the therapy when Se metabolism is altered.</p><p>Despite many studies that have suggested a beneficial effect from Se supplementation to general health protection, most of them have remarked that it is limited to general health protection, most of them have remarked that it is limited to the initially inadequate Se status. Conversely, care should be taken when using supplements because excessive Se intake leads to toxic effects, and recent studies have shown that even sub-toxic doses may be negatively impacting, for example by increasing the risk of type 2 diabetes.</p> <br><p></p>