Antioxidants Prolong Life
May 17, 2005
An antioxidant enzyme that protects cellular energy production has been found to prolong the lifespan of mice by 20%. A world-renowned researcher thinks that this same method may also be used for humans.
Antioxidants prolong life. If you manipulate with the genes of mice to form extra much of the antioxidant enzyme catalase, the mice will live on average 20% longer.
At the same time they age more slowly, as seen by a lower tendency to cataracts as well as less age-related weakening of the heart muscle. Something similar can be achieved with human beings, though manipulation with human genes is not an option.
This is the message from one of the heavyweights in biological medicine, the American Peter S Rabinovitch, professor of pathology at the University of Washington. Rabinovitch is famous for his part in the development of the so-called flow cytometry, a technique for counting and sorting cells according to their biological properties. Flow cytometry is used every day around the world when researchers count and collect, for example, cancer cells, cells with special genetic properties, etc.
The enzyme catalase, which the message is about, is a known antioxidant. It neutralizes hydrogen peroxide and thereby prevents the formation of free oxygen radicals, which could otherwise damage the DNA of cells, cause cancer or kill the cells.
Rabinovitch and his team manipulated the mice’s DNA in three different ways. Some were made to produce more catalase in the cell nuclei, where the DNA is located. Others were manipulated to produce more in the liquid interior of the cells, the cytoplasm. Finally, a third group was manipulated to produce more in the cells’ mitochondria, i.e. the microscopic energy factories that swim around in the cytoplasm and transform oxygen and carbon into carbon dioxide and water – and energy.
Which mice lived the longest? The latter did! While the first two groups only lived marginally longer, protecting the mitochondria could extend life by 20%.
Protect your mitochondria
A dominant theory is that aging is linked to the degeneration of these strange micro-organs found in all cells. There are mitochondria in egg cells, but not in sperm cells, and therefore both men and women inherit their mitochondria from their mothers.
A mitochondrion has its own DNA, which compared to the DNA in the cell nucleus is quite vulnerable to free oxygen radicals. Unfortunately, mitochondria themselves produce oxygen radicals. This is an unavoidable side effect of their function. The production increases as the mitochondria age, which affects the entire cell machinery. It is easy to imagine that when the mitochondria age, the cells also age.
Rabinovitch emphasizes that the new study supports the theory that free radicals cause aging, and that they are formed primarily in the mitochondria. This could significantly target the search for life-extending drugs, which Rabinovitch recommends.
An obvious option, which he does not mention, is already available, namely the mineral Selenium. Several studies, including by Rabinovitch himself, have shown that selenium prevents cancer, and trials to definitively determine this are underway. In selenium-poor countries such as Denmark, selenium supplementation will lead to significantly increased production of the antioxidant enzyme glutathione peroxidase (GSHpx).
The interesting thing is that GSHpx neutralizes hydrogen peroxide in exactly the same way as catalase.
By: Vitality Council
References:
1. Science (DOI 10.1126/science.1106653).
2. Rudolph RE, Vaughan TL, Kristal AR, Blount PL, Levine DS, Galipeau PC, Prevo LJ, Sanchez CA, Rabinovitch PS, Reid BJ Serum selenium levels in relation to markers of neoplastic progression among persons with Barrett’s esophagus. J Natl Cancer Inst. 2003 May 21;95(10):750-7.
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