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Effects of soft electrophiles on selenium physiology
1Earth System Science and Policy, University of North Dakota, Grand Forks, ND, USA.
Free Radical Biology & Medicine
|July 28, 2018
Summary
Neurotoxic electrophiles, like mercury, can deplete selenium (Se) in the body, impacting essential selenium-dependent enzymes. Understanding this interaction is crucial for assessing neurological health risks and protecting vulnerable populations.
Area of Science:
- Biochemistry
- Neuroscience
- Toxicology
Background:
- Selenium (Se) is vital for selenoproteins, including selenoenzymes, which protect against oxidative damage and regulate various physiological processes.
- Selenoproteins are particularly important for brain development, health, and function.
- The 21st proteinogenic amino acid, selenocysteine (Sec), is a potent nucleophile and a target for neurotoxic electrophiles.
Purpose of the Study:
- To review the impact of neurotoxic electrophiles on selenium metabolism and selenoprotein function.
- To highlight the need for considering combined exposures to neurotoxicants and their effect on selenium status.
- To identify vulnerable populations at risk due to poor selenium status and neurotoxicant exposure.
Main Methods:
- Review of existing epidemiological and environmental studies on neurotoxicant exposure.
- Analysis of the biochemical interactions between electrophiles and selenium.
- Evaluation of the role of selenium status in mitigating or exacerbating neurotoxicant effects.
Main Results:
- Neurotoxic electrophiles, such as methyl-mercury and elemental mercury, sequester selenium, potentially impairing selenoprotein activity.
- Combined exposures to various neurotoxic electrophiles can have synergistic effects on selenium depletion.
- Individuals with poor selenium status may be more susceptible to the neurotoxic effects of these electrophiles.
Conclusions:
- Assessing aggregate exposures to neurotoxic electrophiles in relation to dietary selenium intake is essential for public health.
- Further research is needed on inherited or acquired disorders of selenium homeostasis and their influence on neurotoxicant vulnerability.
- Understanding the interplay between selenium metabolism and neurotoxicant exposure is critical for preventing neurological disorders and neurodegenerative diseases.
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