About SEP / Selenoprotein:
There are three principal families of selenoprotein, and they each have different identified functions.
●Glutathione Peroxidases: There are four known enzymes in this family. These enzymes all catabolize hydroperoxide, removing glutathione. This means that they have antioxidant functions.
●Iodothyronine Deiodinases: There are three known enzymes in this family. They are known to have antioxidant properties, and they regulate cellular protein thiol redox status by reducing thioredoxin.
●Thioredoxin Reductases: There are three known enzymes in this family. Collectively they regulate thyroid hormone and are thought to be important in metabolic regulation and embryonic development.
Among other types of selenoprotein are:
●Selenoprotein W, which has antioxidant properties.
●Methionine sulfoxide reductase B, which may remove an oxygen species.
●Selenoprotein P, which is thought to play a role in selenium transport and be an antioxidant.
Together and separately, selenoproteins are hypothesised to play a role in neutralization of free radicals and potentially the slowing of the aging process ; inflammation and immunity responses ; preventing and repairing damage from muscular dystrophy, cardiovascular disease, neurological disease (such as Alzheimer’s and Parkinson’s), and cancer . They may play an important role in the endocrine system regulating thyroid hormone and in male fertility through spermatogenisis . They are also understood to have important roles in cell maintenance, skeletal muscle regeneration, and calcium homeostasis.
On a normal diet, the highest selenium levels are found in the kidney and liver, with decreasing levels in the spleen, pancreas, heart, and brain. But when dietary selenium is scarce, the brain retains its selenium longest. This may indicate that selenium, and thus the selenoproteins, play a significant role in the central nervous system