3.2. Oxidative Stress Analysis
OXIDATIVE STRESS, STD
The participants all underwent baseline oxidative stress screening prior to glutathione treatment and post-glutathione treatment upon completion of the study where appropriate. One patient was unable to complete the full study and did not undergo the post-treatment oxidative stress screen. The results of the oxidative stress testing are outlined in Three subjects’ baseline glutathione levels were below the normal ranges during the pre-treatment assessment. Two of these three subjects’ below normal glutathione levels improved to normal ranges with oral glutathione supplementation. The total antioxidant capacity did not improve in one subject, and even worsened in another subject. Cysteine is the rate-limiting amino acid for glutathione production. There were no pre- and post-treatment differences in the cysteine levels in all patients supplemented with oral glutathione. Sulfate is produced from cysteine via sulfoxidation. Sulfate is important in detoxification reactions, and is essential for GI function and joint health. A high cysteine/sulfate ratio or low sulfate level may indicate oxidative stress. Two subjects showed greater than one standard deviation improvement in sulfate levels after treatment, and three subjects showed at least one standard deviation decrease in their cysteine/sulfate ratio after treatment. Cystine is the oxidized product of cysteine and is the predominant form in blood due to its greater relative stability. Both the cystine and cysteine/cystine ratios were within the normal ranges for all patients. The oxidative panel looked at two protective enzymes, namely, superoxide dismutase and glutathione peroxidase. The function of these enzymes is to protect against oxidative stress by reducing superoxide anions to hydrogen peroxide and from hydrogen peroxide to water, respectively. Four of the six subjects experienced >1 std deviation increase in glutathione peroxidase from baseline, and two of the six patients experienced >1 std deviation increase in superoxide dismutase from baseline. One patient with baseline >2 standard deviations below the normal ranges of glutathione peroxidase and superoxide dismutase did not experience any significant enzyme level changes with glutathione supplementation. Lipid peroxides are a direct indicator of oxidative damage to polyunsaturated fatty acids, suggesting an imbalance of redox reactions favoring oxidation. Lipid peroxides were unremarkable for most subjects. Of note, the patient who dropped out had low baseline levels of glutathione and an elevated baseline level of the cysteine/sulfate ratio, superoxide dismutase, and lipid peroxides.