|LE Magazine December 1998 |
Scientists have caused cancer development in rats by treating them with specific cancer-causing chemicals. This causes pre-cancerous lesions in the liver that are low in dna methylation and high in oncogene expression-that is, use of genes that under certain conditions can cause normal cells to become cancerous. Later, these rats develop liver cancer. At least three different cancer-causing procedures have now been used to show that this progress toward cancer can be halted in most cases by extended treatment with SAMe. SAMe not only reduces oncogene expression, but also increases dna methylation. SAMe also greatly reduces the number of animals that later develop liver cancer (Pascale et al. 1992, 1995; Simile et al. 1996).
Betaine has been shown to increase SAMe in rats (Barak et al. 1994) and mice (Wise et al. 1997), and thus both SAMe supplements and methyl supplements that include betaine make good choices in trying to prevent spontaneous cancer in rats.
Because I knew that dna methylation was dependent on methyl metabolism, several years ago I proposed that one reason we lose methylation with age is that our metabolisms just weren't up to snuff as far as maintaining our dna methylation, keeping our homocysteine low or handling other longevity-assuring aspects of methyl metabolism (Cooney 1993, 1994). I also proposed that most of our cells have inherent, built-in deficiencies that compromise methyl metabolism, this leads in turn to a gradual loss of dna methylation, and that these deficiencies and their effects are a mechanism of aging. As such, they contribute to limited normal cell growth, dna breaks, aging and cancer.
On the surface, built-in deficiencies in our dna methylation system or in methyl metabolism seem like a cruel trick of nature. But if we look at it from an evolutionary point of view, it makes a lot of sense. Let's use mice as an example. In nature, most mice will die either of starvation or be killed by predators, disease, drought or other environmental hazards long before they are greatly affected by aging. Likewise, those mice that survive will generally reproduce long before they are greatly affected by aging.
These considerations make a long-lived mouse unlikely and unnecessary. Why? Because it takes lots resources, including energy, essential fatty acids, choline, zinc, folic acid and more to keep an animal healthy and well-maintained for a long life, and these resources would be better expended on reproduction and immediate survival early in life.
So in most animals all metabolism should be quite sufficient-in fact, optimized- for immediate and short-term needs, such as youthful reproduction. This is a fundamental requirement of evolution. It should come as no surprise, then, that various aspects of our metabolisms and dna methylation machinery are not set on "healthful longevity" with an outlook of hundreds of years, but are instead set on a "just-do-it" 5-minute-to-10-year horizon.
Very recently we have shown that epigenetics during embryonic development of mice is changed by methyl-supplemented diets fed to their mothers during pregnancy. These epigenetic factors are very important for health and longevity. We showed this with yellow mice, in which an epigenetically controlled gene both affects coat color and their health and longevity. Even though these mice are genetically identical, their health-that is, their propensity for diabetes, cancer, obesity, longevity-varies greatly (Wolff et al. 1998).
In our new project, we will study rats not only according to their specific ages, but also by following rats periodically over their lifetimes, regardless of how long they live. One of the things we hope to learn from this is which changes actually act as biomarkers for aging and which represent survival mechanisms of special long-lived minorities.
Rats will be maintained as control, methyl-supplemented, or SAMe-supplemented groups, and several determinations will be made. Their longevity will be determined by time of natural death, and also will be monitored at a specific time-point for age-related pathology. Blood will be collected at two-month intervals from specific rats of each group and the parameters of blood plasma homocysteine, red blood cell SAMe (RBCSAM, Wise et al. 1997) and leukocyte dna methylation (Cooney et al. 1997) will be determined. These measures of dna methylation, SAMe and homocysteine will be correlated with the longevity of these individuals.
These studies will use specific methyl supplements and SAMe supplements based on our prior successful studies of metabolism, dna methylation and epigenetics in rats and mice. They should tell us how these supplements affect SAMe, sah, dna methylation and homocysteine, as well as a number of more common measures, such as cholesterol and glucose. They also will demonstrate how these supplements affect age-related pathology and overall longevity. And they should give us information on how the parameters might be used as biomarkers to predict length of life and, more importantly, how to increase length of life.
The recent cloning demonstrations-such as Dolly the cloned sheep and Cumulina the cloned mouse-show that mammals can be cloned from adult cells. This has lots of implications for those of us interested in epigenetics and longevity (Wilmut et al. 1997, Wakayama et al. 1998).
The ability to clone almost certainly means that dna sequence is unchanged from embryonic cells to those adult cells. This underscores that it is largely epigenetics that makes up the "thin blue line" between normal cells and cancer and aged cells. Even as cloning and related techniques make it easier to produce organs, bodies or stem cells, you still need to maintain the epigenetics of tissues and cells; otherwise these will suffer the same fate as the originals. These new discoveries in cloning emphasize that epigenetics is our next big frontier.
The cloning of animals is not just important to our basic understanding of biology and to practical advances in longevity research. It also is an inspiration to those who know that a vastly longer, healthy life is attainable. Ian Wilmut and his team, the cloners of Dolly the sheep, simply didn't believe the many scientists who said that "you can't clone mammals from adult cells." Likewise, those who say we can't live past a certain life span, or that supplements don't improve health, will need to reevaluate their suppositions or risk being left far behind.
We have in front of us a great frontier for supplement research and great opportunities to improve our health and lengthen our lives. Because many of us have been taking supplements for years, epidemiologists now have been able to prove that supplements have health benefits. But this is only the beginning. Optimal levels and optimal combinations of supplements are not known because supplement research has been neglected in the past. Supplement research will now expand greatly, and holds enormous promise to vastly improve our health, well being and longevity.
|Just how important is this research . . . to you?|
The Life Extension Foundation already has contributed $18,000 to Dr. Craig Cooney's research. However, contributing the balance of what is needed has been difficult. Once again, much of our resources have been diverted to fighting legal battles to protect individual health rights. Since 1987, the harassments of government bureaucracies have repeatedly diverted funding intended for critical research that could radically extend life span. We thank members for participating in protests against the fda and other government agencies whose illegal actions pose a serious threat to our right to exist.
The Life Extension Foundation supports scientific research primarily through membership dues and product purchases. While we continue to fund ongoing research projects, we cannot all provide the funding Dr. Cooney needs now to start his project. As a result, we are asking for donations from members.
We have set up the Cooney Research Project, and ask that members who would like to see this important research commence send donations payable to the Life Extension Foundation, P.O. Box 229120, Hollywood, Fla., 33022. Or, phone in your donation by calling 1-800-544-4440.
Please indicate that your donation is for the Cooney Research Project. All donations we receive for the next several months will support this research that could lead to a major breakthrough in the fight against aging. -The Foundation
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