Selenium plays multiple critical roles in the body, primarily through its incorporation into selenoproteins.
Key Functions of Selenium
Selenium is not simply an element; it's an essential component of approximately 25 different selenoproteins [1]. These proteins are involved in various biological processes.
Roles of Selenoproteins
The selenoproteins, which contain selenium, perform several crucial functions:
- Thyroid Hormone Metabolism: Selenium is essential for the proper functioning of enzymes that convert thyroid hormones into their active forms [2].
- DNA Synthesis: Selenoproteins contribute to the process of making new DNA, which is crucial for cell growth and repair [2].
- Reproduction: Selenium plays a significant role in reproductive health [2]. This is supported by studies showing its importance in fertility in both males and females.
- Protection from Oxidative Damage: Selenoproteins, particularly glutathione peroxidases, act as antioxidants, protecting cells from damage caused by free radicals [2, 4]. This is critical for preventing cellular aging and various diseases.
- Protection from Infection: Selenoproteins play a role in the immune system, helping the body fight off infections [2, 3].
Examples of Selenoproteins
Here are a few examples of important selenoproteins:
- Thioredoxin Reductases: These enzymes are crucial for antioxidant defense and redox regulation within cells [1].
- Glutathione Peroxidases: These enzymes protect cells from oxidative damage by detoxifying harmful hydrogen peroxide [1].
- Selenoprotein P: This protein is involved in selenium transport and antioxidant defense [1].
Selenium Deficiency
Insufficient selenium levels can lead to various health issues due to the impaired function of these selenoproteins. These conditions can affect the thyroid, immune system, and reproductive functions.
Conclusion
In summary, selenium is vital for various physiological processes due to its role in selenoproteins. It is critical for thyroid function, DNA synthesis, reproduction, and protection against oxidative damage and infection. These functions highlight the importance of adequate selenium intake for maintaining overall health.
