Glutathione levels in blood from ataxia telangiectasia patients suggest in vivo adaptive mechanisms to oxidative stress

Objective: To evaluate an in vivo pro-oxidant state in patients with ataxia telangiectasia (AT). Methods: A set of oxidative stress endpoints were measured in 9 AT homozygotes, 16 AT heterozygotes (parents) and 83 controls (grouped in age ranges as for patients and parents, respectively). The following analytes were measured: (a) leukocyte 8-hydroxy-2′-deoxyguanosine (8-OHdG); (b) blood glutathione (GSSG and GSH); and (c) plasma levels of glyoxal (Glx) and methylglyoxal (MGlx). Results: AT patients displayed a significant decrease in blood GSSG (p = 0.012) and in MGlx plasma concentrations (p = 0.012). A non-significant decrease in the GSSG:GSH ratio (p = 0.1) and a non-significant increase in 8-OHdG and Glx levels were observed in AT patients vs. young controls (age range 4–35 years). AT heterozygotes failed to display any significant changes vs. adult controls (age range 36–68 years). Conclusion: No significant increase in oxidative stress biomarkers was detected in blood from AT patients. The decrease in GSSG and MGlx levels in AT patients may suggest an adaptive response to a pro-oxidant state in