Link between Selenium loss and declining cognitive abilities

[gribbon]

Some time back, a French study (which I can't remember) discovered that the loss of neurological abilities and the changing of cognitive function (how the brain processes information, and includes functions such as comprehension, decision-making, memory and learning, abilities that may be lost in dementia) associated with aging is due to a loss of Selenium.

As far as I remember the report from “Epidemiology” stated that "oxidative stress" is one cause of brain impairment, "selenium, which is an antioxidant, may protect against cognitive decline", and the researchers recruited 1,389 French subjects between 1991 and 1993 for a 9-year study with 6 follow-up periods. At study entry, the applicants ranged in age from 60 to 71 years and provided information on social factors, demographic factors and underwent tests to gauge cognitive function and in total, 703 completed the study.

I would be interested to know what the average Selenium levels in the blood were for the subjects? Also, being as it was selenoproteins, (proteins containing selenium) that provided a flexible mind, I would like to know how they affect the chemistry of the neurones. Other than protecting as an anti-oxidant, do selenoproteins have another function in the neurones?

Furthermore, what other factors lead to decline?

[InfiniteNow]

Perhaps it's stated in the study you reference?

Originally Posted by gribbon

Some time back, a French study discovered that...As far as I remember the report from “Epidemiology” stated that ...

[gribbon]

Perhaps it's stated in the study you reference?

I can't remember word for word what that study said! The numbers are as much as I was able to find out, and the rest is as much as I could remember, but if you look at my questions that's not particularly important...

[InfiniteNow]

Well, most good studies would provide the data you seek, or even list reference studies which do, that's all.

[gribbon]

Well, most good studies would provide the data you seek, or even list reference studies which do, that's all.

Well, perhaps instead of dropping scornful comments all the time, you could find me one...

[W.Davidson]

Selenium is used by the antioxidant enzyme, glutathione peroxidase. It has no other known function.

Low selenium could arise as a result of low levels of selenium in the diet. An area of China where there was very low levels of selenium had a very high incidence of a rare disease. Intensive research revealed that selenium deficiency was the cause. Low selenium could also result as a result of high demand for glutathione peroxidase due to high levels of free radical production. The selenium reserves would be used up.

Cognitive decline happens to everyone. Pathological cognitive decline (dementia) is known to involve neuronal death due to excessive production of damaging free radicals such as hydroxyl, superoxide, nitric oxide etc. The most damaging is hydroxyl radical. Aberrant immune reactivity is also involved.

[Monomer]

Originally Posted by gribbon

I would be interested to know what the average Selenium levels in the blood were for the subjects?

1.09 micromoles per litre at the beginning of the study: AOL Ability - Selenium Loss Linked to Cognitive Decline in Aged

To get the full details you'd have to subscribe to the journal, but here's the abstract.

Originally Posted by gribbon

Also, being as it was selenoproteins, (proteins containing selenium) that provided a flexible mind, I would like to know how they affect the chemistry of the neurones. Other than protecting as an anti-oxidant, do selenoproteins have another function in the neurones?

I haven't really had time to read it, but maybe this will answer your question.

Originally Posted by gribbon

Furthermore, what other factors lead to decline?

From what I've read, other factors leading to cognitive decline include diabetes, hypertension, major surgery, depression, stress, genetics, lack of exercise, and lack of cognitively challenging tasks. This list isn't exhaustive and I'm sure there are many other factors.

[W.Davidson]

Originally Posted by Monomer

From what I've read, other factors leading to cognitive decline include diabetes, hypertension, major surgery, depression, stress, genetics, lack of exercise, and lack of cognitively challenging tasks. This list isn't exhaustive and I'm sure there are many other factors.

These factors are associated with cognitive decline. That does not mean that they cause it, although the last two might be said to contribute.

The others are associated with aberrant immune function, as is cognitive decline. That's the common denominator.

[gribbon]

Ahhh...thanks both of you...

I'll try looking into the bit about Selenoproteins again...maybe this time with more success....

...due to excessive production of damaging free radicals such as hydroxyl, superoxide, nitric oxide etc. The most damaging is hydroxyl radical. .

I found something similair in a text book, but I think it is still quite new science. Do you know of any research institutes that are currently researching this topic?

Thanks...

[Monomer]

Originally Posted by gribbon

Do you know of any research institutes that are currently researching this topic?

These guys are looking at cognitive decline and antioxidants, including selenium:

Brain Research Institute


Also the University of Montpellier, which is where that French study, from your first post, was conducted.