Life Extension Magazine®
There is a major paradigm shift in the way the medical profession is approaching aging, and the annual A4M conference has been a prime forum for its display. Here are ample reasons why.
By Thomas Donaldson, Ph.D.
The annual conference of the American Academy of Anti-Aging Medicine, held in Las Vegas, was typically far-ranging in its presentations. The conference covered topics from brain aging and repair to Alzheimer's detection and prevention, hormone replacement therapy, and anti-aging surgery techniques. Perhaps most controversial was the discussion of actual head transplants.
Here is an overview of those presentations of interest to life extensionists.
Thomas H. Crook, Ph.D., a consultant to several pharmaceutical companies, including Lederle Labs and Bristol Myers Squibb, discussed clinical test reports on phosphatidylserine in the prevention, arrest, and treatment of Alzheimer's disease. He detailed just how our memory deteriorates as we age. His early work on this issue had been with monkeys, but he now has devised human tests that relate easily to those given to monkeys.
Humans show a dramatic decline over time in their ability to remember relations between numbers and symbols. They also show a decline in several tasks based on memory for names, and again on the ability to remember a telephone number long enough to dial it.
One particular test, requiring the subject to remember some information while doing something else unrelated showed considerable decline with age. All of these declines are approximately linear, with no special ages at which we suddenly start failing these tests. Even when conducted on patients between ages 20 and 29, Crook's tests showed an average decline of 25 percent. (As with many such tests, speed played a role: only a short time is allowed for subjects to remember. It would be interesting to use similar tests with no time limit; one simple explanation for part of the decline may simply come from slower thinking as we grow older.)
In exploring ways to prevent this mental slowdown, Crook first tested hyperbaric oxygen, which did not work. He then tried a variety of memory drugs, including piracetam and hydergine, for their ability to preserve younger levels of memory. Phosphatidylserine turned out to be the only drug he found that provably increased memory abilities. In controlled tests at 300 mg/day, Crook found that phosphatidylserine improved performance on various memory tests. It worked best on those with lower scores. Treatment early in the course of Alzheimer's disease showed an effect; late treatment showed no measurable effect.
Besides performance of aged subjects on memory tests, those caring for these patients all noticed a clear improvement. Patients, too, noticed the improvement. These test patients and others were kept on phosphatidylserine for some time afterwards. The best strategy in dosage apparently consists of initial doses of 300 mg a day, followed after several weeks by a constant dose of 100 mg a day. The tests, with a starting dose of 100 mg a day, took about 12 weeks to have an effect; after that, 100 mg a day and 300 mg a day showed little difference.
This talk and Kay's talk were notable because they discussed a (partial) therapy, something we might actually do to help prevent our own memory from deteriorating, with no further basic experiments needed.
In another presentation, Thierry Hertoghe, M.D., of the Academy of General Medicine of Belgium, in Brussels, reviewed the effects of hormone replacement across all the different known hormones. He looked not only at bodily effects such as that on circulation and heart disease, but also on memory. Low levels of thyroid hormones, for instance, can cause both a lack of emotion and a lack of intelligence.
By the age of 85, 30 percent of elderly people become demented. One interesting feature of dementia due to Alzheimer's disease, alcohol, and others, is the low level of the hormone melatonin, produced by the pineal gland. Melatonin acts as a quite powerful antioxidant, and is low at all times in patients with Alzheimer's disease. It may protect our brain by acting as an antioxidant. DHEA (Dihydroepiandrosterone), a precursor of several hormones, has a profound effect against cancers, heart disease, and diseases of our arteries (scanty hair in the armpits provides one useful symptom of low DHEA). DHEA occurs in high levels in our brain, and low DHEA also involves a loss of memory. It improves the metabolic level of neurons and can sometimes make EEG tracings more normal.
Dr. Marguerite Kay, who presented her research on the effects of vitamin E, suggests that Alzheimer's disease is an illnes of the entie bod, not of the brain alone.
DHEA and Memory Moreover, when given to old and young mice, DHEA enhances memory. Some clinical case reports suggest that it can enhance memory in younger people, and completely rejuvenate the memory of old mice. DHEA also works against known memory blocker drugs when given to mice. While these are not results found in human beings, they suggest that humans will feel similar effects. Pregnenolone is an internal hormone closely related to DHEA and the sex hormones estrogen, the androgens and testosterone. It can occur at very high levels; experiments show that it also improves memory in rats and works against memory blocker drugs, just as does DHEA, when given to mice. Our hormones must always remain balanced. Despite the damage it causes when too high, we also need cortisone. At proper levels, cortisone improves our sense of well being. Low cortisone shows up in eczema (an inflammatory rash) and loss of memory. Cortisone also helps our brain work by keeping glucose at the right level. Estrogen reaches low levels some time before menopause, and Hertoghe believes women need added estrogen at that time. Deficiency causes higher cholesterol levels in the blood, making women more subject to heart and artery disease. Estrogen doses in women also improve memory. All the sex hormones occur in both sexes. Estrogen in women has a very important effect on Alzheimer's disease; women taking extra estrogen after menopause decrease their risk of Alzheimer's by as much as 50 to 60 percent. Testosterone and the androgens (a class of hormones rather than a single hormone) have their own separate effects. Levels of androgens in women are 30 percent less than those in men. Lack of androgens causes a thinning of the myelin sheaths surrounding our major nerves, and a loss of memory. Testosterone levels correlate with the number of nerve connections in our brains. They also tend to reduce fluency of speech. Men have an andropause like the menopause of women, with symptoms including shrunken sex organs and apparent starvation or malnutrition. Testosterone also stimulates production of the special growth hormone IGF-1 (insulin growth factor 1), and both IGF-1 and HGH (human growth hormone) decrease when testosterone levels are low. Eighty-five-year-old men have testosterone levels about 85 percent of the level of young men. Young men show daily cycles in their level of testosterone while older men do not. Hertoghe suggests that a normal level of testosterone is about 300 nanograms per liter of blood. Thyroid hormones (a second class of hormones) also decrease in our cell nuclei as we age. This decrease comes from a fall in sensitivity to thyroid hormones. Thyroid hormone levels go down as well in Alzheimer's disease; since low thyroid levels alone can produce loss of memory and dementia, this makes the symptoms of Alzheimer's much worse.
HGH and Sleep HGH and several other pituitary hormones also play a role in our brain. Low levels of HGH cause poorer sleep and lack of REM sleep, the kind we have when we dream. Lack of REM sleep may even decrease ability to remember. Two other pituitary hormones, LH (luteinizing hormone) and FSH (follicle-stimulating hormone) actually rise in aging. FSH causes secretion of hormones from the testes or ovaries. So far, no one has found a positive function of LH in men. A fall in the secretion of HGH, together with continued secretion of somatostatin (a pituitary hormone acting against HGH), provide another example of changes in our pituitary hormones with age. Hertoghe suggests that these changes show loss of some important regulatory process as we age. Luke Bucci, Ph.D., of the University of Utah in Salt Lake City, discussed potential nitrocatechol stimulation of HGH production in the enhancement of brain function and prevention of premature senescence. Bucci reviewed the range of information about substances which might stimulate secretion of HGH when taken orally. HGH itself remains quite expensive, with treatment for a year costing up to $10,000. It cannot be taken orally (it is destroyed by the digestive system), and must be injected. If we can find some less-expensive substance we might take with our food, raising HGH levels would become simpler, and many more people could keep their HGH at younger levels. This in particular could be a means to markedly improve health in many elderly people. The optimistic side of such searches comes from one simple observation. Even in older people with low secretion of HGH, their pituitary glands still make human growth hormone. Some unknown process only blocks its secretion rather than its creation. Many substances will increase HGH secretion, but so far we know much less about their effectiveness, side effects, and dosage, particularly in older people. Several amino acids, for instance, definitely increase HGH in younger patients, but no one has done such tests on elderly patients. Bucci discussed the classes of substances that increase human growth hormone secretion, including amino acids, mixtures of amino acids, dipeptides (two linked amino acids), peptides (small proteins), organic acids, some B vitamins and hormones: If we can find some less-expensive substance, raising HGH levels would become simpler, many more people could keep their HGH at younger levels, and the elderly could enjoy improved health.
Lots of scientific evidence already suggests that vitamin E delays aging of the brain and immune system. Marguerite Kay, professor of microbiology and immunology at the University of Arizona in Phoenix, discussed her own work, which may explain how vitamin E might do this. She looked at a special antigen present in aged cells, called senescent cell antigen (SCA), and the process creating it. Basically, Kay found precursors for SCA by examining cells aged in vitro. On membrane chromatography, its precursors showed up on band 3. They turned out to be a widely known class of proteins called the band 3 proteins. These proteins transport substances through cell membranes in all species and cells so far studied. Kay found that when band 3 proteins degrade, they produce SCA. SCA then signals our immune system to remove cells containing it in their membranes. As cells age, their ability to transport substances across their membranes goes down, a loss critical to survival of the cell. Substances for which transport ability falls off include glucose (the basic sugar supporting many cells) and a variety of ions: Ca++, Mg++, Na+, and others (living cells maintain a different level of ions inside the cell compared to outside). Band 3 proteins show up not just in the outer cell membrane but also in those separating the Golgi bodies, the nucleus, the mitochondria, and other organelles from the rest of the cell. As band 3 proteins themselves age, these essential transport processes break down. Not only does this cause failure of transport for ions and glucose, but also structural changes inside the cell, decreased ability to attach phosphate to the proper molecules (essential to metabolism), degradation of cell parts, and the generation of SCA mentioned above. Normally SCA then causes special antibodies to bind to the cell, leading to its destruction; in aging tissues, however, swamped by too many SCA signals, our immune system fails to clear away degraded cells fast enough. For some time scientists have known that lack of vitamin E accelerates many aging changes. To test whether added vitamin E might protect against cell breakdown, Kay carried out experiments with CBA/CAT female mice starting at seven months (young adult mice) and 40 months (old mice). Control mice received a constant diet containing 50 mg/kg vitamin E and no beta carotene; groups of test mice had vitamin E doses ramping up to 200 mg/kg. On measuring two antibodies to show the effect on immune system destruction of brain cells, animals receiving the highest levels of vitamin E showed the least destruction.
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