Standardization of a Technique for Quantification of Glutathione Concentration in Human White Blood Cells: a Biomarker for Autism?

Standardization of a Technique for Quantification of Glutathione Concentration in Human White Blood Cells: a Biomarker for Autism?

Glutathione is an unusual tripeptide ubiquitous in scientific literature for its antioxidant capacity and its relevance as an indicator of oxidative stress. Glutathione’s role within cellular homeostasis is well documented, but the entirety of glutathione’s biochemical role within the human body remains fervently researched. Deficiencies in glutathione have been linked to patients suffering from a wide spectrum of disorders including, cancer, cardiovascular diseases, and autism (Pastore, Federici, Bertini, & Piemonte, 2003). Much of the research on glutathione centers on the relationship between the reduced (GSH) and oxidized (GSSG) versions of the tripeptide. Fluctuations which lower the ratio of GSH to GSSG are indicative of oxidative damage (Monostori, Wittmann, Karg, & Turi, 2009). It has been noted that a significant percentage of children with autism exhibit reduced levels of intracellular glutathione and correspondent increased levels of oxidative stress (Grannemann, Kern, Gutman, & Trivedi, 2008). The purpose of this study was to standardize a technique to measure intracellular levels of Glutathione in both reduced and oxidized forms within human white blood cells. White blood cells were isolated from whole blood samples and GSH and GSSG were quantified using a photometric method. Intra-assay (±9.0%) and inter-assay (±5.0%) variability of tGSH levels in the white blood cells as well as inter-assay variability of the standard curve concentrations of GSH (±13.2%) were assessed to establish reproducibility of the technique. The correlation coefficients of the standard curve concentrations of GSH from different assays were compared to establish linearity of the measurements (.990, ±.003). The technique will be used to research the possible correlation between GSH/GSSG ratio and behavioral aspects of Autism Spectrum Disorders.