How long do nutrients stay in cells?

[blackbird3]

Nutrients in cells question??

This question may again be too technical but does anyone now how long nutrients used for 'fuel' remain in cells (when they're not being stored - I believe they're only stored in muscle, fat and liver tissue)? For example, if a glucose molecule enters a cell from the blood stream, will it be converted into waste and leave the cell within seconds, or hours or days or longer?

 

[jim mcnamara]

Normally, not very long - on the order of less than a second, probably.

This is a backwards way of looking at it: glucose can react with other molecules and damage them. Glycosylated hemoglobin is an example.
Diabetics in poor control have higher than normal blood glucose levels. Long term, these patients develop problems like nephropathy, retinopathy... etc.
This is tissue damage. It is at least partially due to elevated blood glucose levels. Glycolsylation is not a good thing.

Running this forward now: if glucose were "safe" to have running loose in large quantities inside a cell, there would be no problems like the ones described above. So, (being anthropomorphic) the cells have to deal with glucose in a timely way - either burn it, pack it into glycogen, or turn it into fat. Fat and glycogen are not reactive like glucose.

Leaving glucose running around loose for several minutes is not a good option, from the cell's point of view.

There is considerable evidence that lab animals fed a diet too high in calories show more internal mitochondrial damage than animals fed a diet that is just barely sufficient calorie-wise. This damage to the mitochondrion is because it has to deal with extra glucose processing, it is assumed.

...The "mitochondrial theory of aging"

Ignore the plug for the pills - this is meant for non-technical folks to read.

http://juvenon.com/science/overview.htm There are some citations on other pages linked to this one