Redox Analysis of Human Plasma Allows Separation of Pro-Oxidant Events of Aging from Decline in Antioxidant Defenses
Jones DP, et al. Redox Analysis of Human Plasma Allows Separation of Pro-Oxidant Events of Aging from Decline in Antioxidant Defenses. Free Radic Biol Med. 2002;33(9):1290-300.
Link to Original Publication: https://pubmed.ncbi.nlm.nih.gov/12398937/
Oxidative stress occurs when there are more free radicals than antioxidants in our bodies. Oxidative stress increases with age and plays a role in age-related declines and diseases. The glutathione antioxidant system acts to neutralize free radicals by recycling between reduced (GSH) and oxidized (GSSG) forms. Only when glutathione is in the reduced form (GSH) is it able to protect cells by binding to free radicals.
Glutathione (GSH) is oxidized to GSSG in this process, but can be recycled back to its reduced, protective form.
This study measured cysteine/cystine and the antioxidant glutathione (GSH) and glutathione disulfide (GSSG) redox in the plasma of healthy adults up to age 85. This allowed researchers to separate evaluation of an increase in oxidative events from a decline in antioxidant function. The analysis of the samples showed that pro-oxidant events tend to increase continuously throughout life at a relatively slow rate. Meanwhile, the antioxidant functions do not noticeably decline until middle age and then decline rapidly. This suggests that interventions to support antioxidant function may be a useful strategy to help protect against age-related declines mediated by oxidative stress.