The Durk Pearson & Sandy Shaw®
Life Extension NewsTM
Volume 13 No.
5 • October 2010
Life Extension Sodium Selenite Increases Mean and Maximum Lifespan of Banana Fruitfly
You may not want to increase the lifespan of pesky banana fruitflies making nuisances of themselves around your fruit, but as a model organism for lifespan studies, they work well. A 1989 paper reports on a study of sodium selenite supplementation in banana fruitflies (added at nine concentrations: 1, 5, 10, 25, 50 100, 500, 1000, and 2500 uM) increased mean and maximum lifespans and increased catalase and peroxidase activity. “The best suited concentration of SS [sodium selenite], 5 uM, increased the median life span of males by 11.63% and that of females by 7.69%. The maximum life span was increased by 5.06 and 3.29% in males and females, respectively.”
In the control flies, reared on standard corn meal agar medium without sodium selenite supplementation, males exhibited a decline in catalase activity of 59.4% up to 13 days followed by an increase of 55.8% up to 37 days; in females, catalase activity declined during the first 25 days by 60% followed by a 38.64% increase at the 37 day stage. Both males and females showed a statistically significant increase in the baseline activity of catalase as a result of sodium selenite supplementation followed by similar age-related changes as shown by the control flies. The peroxidase changes were more complex; the authors infer from these changes that catalase and peroxidase are inversely related and that the changes associated with reproduction may be an adaptive response to higher levels of hydrogen peroxide production.
We each take 400 ug. (2 capsules) of our sodium selenite per day.
- Kaur et al. Effect of sodium selenite on antioxidative enzymes of banana fruitfly. Gerontology 35:188-191 (1989)