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Updated: Jul 4, 2026
03:35
Rapid Quantification of Oxidized and Reduced Forms of Glutathione Using Ortho -phthalaldehyde in Cultured Mammalian Cells In Vitro
Published on: June 28, 2024
Glutathione peroxidase enzyme activity in aging
Sara E Espinoza1, Hongfei Guo, Neal Fedarko
1Johns Hopkins Medical Institutions, Baltimore, Maryland, USA. espinozas2@uthscsa.edu
Summary
Glutathione peroxidase (GPx) activity declines with age in disabled older women, suggesting a link between aging and reduced antioxidant defense. This decrease is not explained by common chronic diseases but is associated with body mass index.
Area of Science:
- Gerontology
- Biochemistry
- Oxidative Stress
Background:
- Free radical damage is a proposed contributor to the aging process.
- Reduced activity of antioxidant enzymes like glutathione peroxidase (GPx) may increase free radical levels.
- This study investigates GPx activity decline in aging disabled women.
Purpose of the Study:
- To examine the association between chronological age and glutathione peroxidase (GPx) activity.
- To investigate GPx activity in a cohort of disabled, community-dwelling older women.
- To determine if age-related GPx decline is linked to specific chronic diseases.
Main Methods:
- Measured whole blood GPx activity in 601 participants from the Women's Health and Aging Study I.
- Employed linear regression to assess cross-sectional associations between GPx activity and age.
- Adjusted for covariates including hemoglobin, coronary disease, diabetes, selenium, BMI, and weight loss.
Main Results:
- A significant inverse association was found between GPx activity and age (regression coefficient = -2.9, p <.001).
- GPx activity decreased by 2.9 micromol/min/L for each year increase in age.
- The association remained significant after adjustments, except for body mass index and weight loss.
Conclusions:
- This is the first study to report age-related GPx decline in disabled older adults.
- GPx activity decreases with age in older women with disability, particularly after age 65.
- The observed decline is not linked to previously identified disease-related alterations in GPx activity.
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