Hi, While I don't know much about mosquito cells in particular, for mammalian cells in general there are several possibilities. Assuming the oxidative stress burden continues and the gluthathione peroxidase/reductase system is overwhelmed, the cell could die. The cell could also recover if  this is a transient decrease in reduced glutathione. I'm not sure about the details of your experiments but a  time course may answer that question and GPx/GR activity assays may also yield useful data. Good luck.

Tyler

Hi, first be sure that you get reliable datas. I experienced the measurments of reduced and oxidized pools of Glutathion and ascorbate on cells and supernantants and this is a bit tricky. A lot of techniques (and commercial kits also) lead to an overestimation of the oxidized pool of glutathion in comparison with total amount of glutathion. Samples must have been properly frozen and then you have to work very quickly when doing these measurment. For the fate of your mosquito cells, I agree with Tyler's response. good luck.

Hello, my suggestion is first you should have a look to the available data of glutathione rates in mosquito. The reference always is GSH/GSSG ratio, as you explain before your samples show high rates of oxidized glutathione (GSSG). If sample collection is done to avoid further oxidation another possibility would be that this cells require an oxidative environment for proper physiology but this is a speculation.

I agree with what is said by others here. Glutathione (reduced form) measurement is tricky. The method employed can have bearing on the end result. It is hard to say what the effect of 30% of total glutathione available in reduced form mean especially in a mosquito cells which most of us may not have any experience working with. In an organism, glutathione levels vary in different cell types.

The questions I would ask is that what is the total level of glutathione and is there something unusual about that level in those cells. What cell types are you comparing with?

Overall reduction in the total level of glutathione may have toxic consequences but if the cells have elevated total glutathione levels then it can very well use glutathione to fine tune various processes including oxidative stress control or signaling. 

Usually oxidized forms of GSH are less than 1% of total glutathione. As stated by others, glutathione measurement is not easy even for esperts. Please pay attention to the (pre) analytical pase before drowing conclusions. How do you measure GSH and oxidized (I suppose disulfide) forms?

I agree that true quantification of GS-SG and GSH is tricky and quite indirect. If your findings are alright, then low GSH levels might be due to the production of high levels of H2O2 and enhanced activity of glutathione peroxidase (which rapidly promotes oxidation of GSH to GS-SG). You may validate such a possibility by determining the levels of H2O2 and activity of glutathione peroxidase. It is also likely that ratio of NAD(P)H to NAD(P)+ might be low in such cells (which could be due to low metabolic rate) and reduced glutathione reductase activity.If your estimations are right, you have a good experimental model to evaluate significance of regulation of GSH and GS-SG levels more precisely vis-a-vis related/linked metabolic events. 

Thank you all for your contributions. I found them useful.

Hi Guys, I saw all the discussion about measuring reduced GSH is nontrivial. We are certainly aware of this challenge. We recently developed the first quantitative fluorescent probe --ThiolQuant Green-- for GSH measurements in live cells. ThiolQuant Green can be used with both confocal microscopes and flow cytometry. here is our recent publication. http://pubs.acs.org/doi/abs/10.1021/cb500986w

Note: this is for GSH only. not for total GSH + GSSG, also not for GSH/GSSG ratio.

We are interested in collaborations. Shoot me an email at [email protected] if you want to try out this probe. Thanks!