Because of the toxic nature of zinc, please do not do any supplemental zinc intake without knowledge of a doctor and only on his advice. For information on zinc and health problems read this – a little more than half way down the page under the heading “Health Risks from Excessive Zinc”. The rest of the article is good also. Bookmark it and go back to it after you read the following.
This is an interesting study about zinc and does deserve some attention as the National Institutes of Health provided funding for the research. The University of Michigan did the research and the findings appear in the July 8 issue of the Journal of Molecular Biology.
The findings showed that Amylin can display two characteristics. In people that have normal levels of zinc and are otherwise healthy, amylin assists in blood glucose management. An analog of amylin, named Symlin is used with insulin to manage blood glucose levels in people with diabetes. In molecular language, zinc prevents amylin, which is also known as Islet Amyloid Polypeptide, from forming clumps which can lead to the formation of ribbon-like structures called fibrils.
This happens in an environment that is zinc-starved and the fibrils become linked to some human diseases, many of them in the area of dementia. The important part is that zinc binds to amylin, at a point near the middle of the amylin molecule, the amylin molecule kinks, which interferes with the formation of toxic clumps. In the current work, they show that the binding of zinc in the middle makes one end of the amylin molecule, called the N-terminus, become more orderly.
In addition, the researchers found that before amylin can begin forming fibrils, zinc must be rousted from its nesting place. This eviction is costly in energetic terms, and the sheer expense of it discourages fibril formation. And because a single zinc molecule can bind to several amylin molecules, it ties up the amylin in assemblages that, unlike certain other aggregations, are not intermediates in the pathway that leads to fibril formation.
However zinc, like amylin, has a dual nature. At conditions similar to those outside islet cells, where even a tiny amount of amylin aggregates in the blink of an eye, zinc inhibits fibril formation. But in conditions resembling the inside of the cell, the inhibitory effect begins to wane and other factors, like insulin, take on zinc's security guard duties.
Amylin has not one, but two binding sites for zinc. Zinc prefers to bind at the first site -- the one in the middle of the amylin molecule, where its binding discourages fibril formation. But when there's too much zinc around, all the binding sites in the middle positions are occupied and zinc must attach to amylin at the second site, which counteracts the effect of the first site. This may explain why decreased levels of insulin -- the backup security guard -- inside islet cells of diabetics result in islet cell death.
Also read this blog about natural sources of zinc.
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