Hydrogen peroxide triggers an increase in cell surface expression of system xc in cultured human glioma cells

Leah A. Chase, Mary VerHeulen Kleyn, Na Tasha Schiller, Abby Goltz King, Guillermo Flores, Sasha Balcazar Engelsman, Christina Bowles, Sara Lang Smith, Anne E. Robinson, Jeffrey Rothstein

Research output: Contribution to journalArticlepeer-review


System xc exchanges extracellular cystine for intracellular glutamate across the plasma membrane of many cell types. One of the physiological roles of System xc is to provide cystine for synthesis of the antioxidant glutathione. Here we report that hydrogen peroxide (H2O2) triggers the translocation of System xc to the plasma membrane within 10 min of the initial exposure. Specifically, we observed a three-fold increase in 35S-L-cystine uptake following a 10 min exposure to 0.3 mM H2O2. This effect was dose-dependent with an EC50 for H2O2 of 65 μM. We then used cell surface biotinylation analysis to test the hypothesis that the increase in activity is due to an increased number of transporters on the plasma membrane. We demonstrated that the amount of transporter protein, xCT, localized to the plasma membrane doubles within 10 min of H2O2 exposure as a result of an increase in its delivery rate and a reduction in its internalization rate. In addition, we demonstrated that H2O2 triggered a rapid decrease in total cellular glutathione which recovered within 2 h of the oxidative insult. The kinetics of glutathione recovery matched the time course for the recovery of xCT cell surface expression and System xc activity following removal of the oxidative insult. Collectively, these results suggest that oxidants acutely modulate the activity of System xc by increasing its cell surface expression, and that this process may serve as an important mechanism to increase de novo glutathione synthesis during periods of oxidative stress.

Original languageEnglish (US)
Article number104648
JournalNeurochemistry International
StatePublished - Mar 2020


  • Cystine/glutamate exchanger
  • Glutathione
  • Ischemia
  • Membrane trafficking
  • Neurotransmitter transporter
  • Oxidative stress

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Cell Biology

Fingerprint Dive into the research topics of 'Hydrogen peroxide triggers an increase in cell surface expression of system x<sub>c</sub> <sup>−</sup> in cultured human glioma cells'. Together they form a unique fingerprint.

Cite this