stupid question: why do serum starving? - (Dec/15/2005 )
I know people normally do serum starving before treating the cells with certain enzyme inhibitors. I know that serum starving can cause all cells to enter G0 phase, and I would understand that if serum starving is used in cell cycle studies. However, for treatment of enzyme inhibitors, what is the point of serum starving the cells?
Serum is full of proteins that can inhibit enyme activity, hence why you use a serum-based media to wash cells after trypinising - to deactivate the trypsin.
When studying enzyme activity in cell culture, you want to eliminate the proteins contained in serum that deactivate the normal enzyme activity.
If you are adding enzyme inhibitors and want to see if they work specifically, removing the serum helps you verify that it is the inhibitor and not the serum proteins.
Hope this helps,
we need to synchronize the cells before this kind of experiment...
after O/N starvation, cells are cultured for some minutes (or hours) in normal medium in the presence of not of the inhibitor such as the initial enzymatic activity is null and do not increase significantly if inhibited, in contrary to control conditions in which the activity will reach the maximum in all the cells
we obtain a better shift in inhibition
imagine what append in a population of cells with a broad spectrum of activity: inhibitor will have more troubles to downregulate enzymes with high activity and will be very active on onzymes with low activity... very difficult to observe and to interprete
that's my point of view