2 replies to this topic

[caston]

I think that AGE's are a very big piece of the puzzle in aging and we often talk about glycation here but also about glycosylation which appears to be an enzymatic type of the former?

Does anyone have any important information or links about how the two processes relate to aging or would like to write about and or discuss them?

thanks,

Chris

Edited by caston, 21 January 2008 - 05:36 PM.

[niner]

I think that AGE's are a very big piece of the puzzle in aging and we often talk about glycation here but also about glycosylation which appears to be an enzymatic type of the former?

Does anyone have any important information or links about how the two processes relate to aging or would like to write about and or discuss them?

thanks,

Chris

Wikipedia has pages on both glycosylation and glycation. Glycosylation is when sacharides, typically complex, are attached to proteins in a specific location via an enzymatic process. This is something that you want to happen for proper function. Glycation, on the other hand, is a chemical (non-enzymatic) process wherein very simple sugars (usually glucose or fructose, I think) attack random basic nitrogens on proteins. As far as I can tell, glycation is nothing but badness. I'm not aware of any good that comes of it, but given the convoluted nature of biochemistry, ya never know...

[Bram]

Right, like niner said:

Glycosylation refers to the addition of one or more saccharides to an enzyme. This happens all the time and has a lot of functions. For example, a saccharide can be added to let the cell's transport system know where a newly constructed enzyme should be going. Or it could 'activate' or 'deactivate' the enzyme's function on demand depending on whether it is needed or not. As you said, this glycosylation happens by enzymes, so there's one enzyme that adds saccharides to other enzymes. This glycosylation basically has nothing to do with aging at all - it's a normal part of cell functioning. It's one of the so called "post-translational modifications", another example being phosphorylation.

Glycation is also the addition of saccharides to an enzyme, except that it is unwanted, or at least not performed in a regulated fashion (ie, by other enzymes). This is thought to be involved in aging, as well as a ton of other stuff like diabetes and alzheimer's. I don't know how exactly though..