LITMIR.BIZ

Скачать книгу

straws, upon the surface flow; He who would search for pearls must dive below.

      John Dryden, All for Love

       The New Aging Paradigm

      Since the 1960s, a number of theories of aging have evolved. They are based on the degree of knowledge present at a given time. Today this degree of knowledge is proceeding exponentially! In reality, there is no single cause of aging. Aging is a complex series of events that changes from year to year for each individual as he or she interacts with the environment. It can best be conceptualized as a change in a different series of gene activity, as we move through childhood to “adolescence to adulthood and eventually old age. A review of the theories of aging popular in the past gives a general idea of some of the fundamental events involved.¹ Familiarity with these general theories should result in an understanding of the basic concepts behind the clinical treatment of aging and the aging codes (Diagram II-1).

      Since the mid-1990s, some startling new information has led me to the formation of a new theory of aging that is based and focused more on the ultimate source of aging itself: DNA. This theory, along with the information on the importance of stem cells and their contribution to the aging process, constitutes this new paradigm of aging. It will be discussed in more detail at the end of this chapter.

      

       Past Theories

      Wear-and-Tear Theory The wear-and-tear theory of aging was originally presented by Dr. August Weismann, a German biologist. This theory focused on the fact that the body and its cells are damaged by overuse and abuse; that is, the specific organs are worn down by toxins in diet and in the environment. Most specifically, Dr. Weismann’s theory focused on the detrimental consumption of fat, sugar, caffeine and alcohol, as well as the harmful effects of the sun’s ultraviolet rays. The wear-and-tear process is not confined to our organs; it also takes place at the cellular level.

      Neuroendocrine Theory of Aging Developed by Vladimir Dilman, Ph.D., a Russian research scientist, this theory elaborated on the wear-and-tear theory by focusing more specifically on the neuroendocrine system. Dr. Dilman’s concept of aging focused on the complicated network of biochemicals that controls the release of hormones and, therefore, regulates other vital body functions. Dr. Dilman stated that during youth, “our hormones work together to regulate many bodily functions, including our responses to stress from the environment, as well as changes in our diet and mental state.” Dr. Dilman further stated that “the hypothalamus governs the release of key hormones that regulate virtually all organs in the body through a complex series of chain reactions.” According to this theory, the hormones are vital for repairing and regulating body functions, and when aging causes a drop in these key hormone productions, it alters the body’s ability to repair and regenerate itself as well. Most important, Dr. Dilman stressed how hormone production is highly interactive: that is, the drop in the production of any one of the hormones will probably have a feedback effect on the whole mechanism, signaling other organs to alter their release of hormones as well. In essence, the neuroendocrine system is like a symphony, irreparably ruined by discord of any one instrument. Because of Dr. Dilman’s theory, the concept of hormone replacement remains a key component of any anti-aging treatment.

      Genetic Control Theory of Anti-Aging According to this theory, obsolescence is programmed into our genes and therefore encoded in our DNA. The theory is that everyone is born with a unique genetic code and a fixed predisposition to certain types of age-related diseases. It stresses that genetic inheritance has the preponderance of effects on how quickly a person ages and how long a person lives. It is a deterministic theory, comparing humans to a machine that is preprogrammed to self-destruct. As a result of this theory, anti-aging medicine concepts began to stress the importance of supplying the building blocks of DNA within each cell. Although many aspects of this theory have been supported by research on DNA, the one of complete determinism by a preprogrammed set of genetic sequences has been shown not to be completely true. What is true, is that we inherit genetic tendencies, not genetic certainties.

      Free Radical Theory of Anti-Aging Originally introduced by Dr. Gershchman in 1954, this theory was further expanded by Dr. Denham Harman of the University of Nebraska College of Medicine. A free radical is any molecule that differs from conventional molecules in that it possesses a free electron. This property makes it react with other molecules in a highly volatile and destructive way. In a conventional molecule, the electrical charges are balanced. Electrons normally reside in pairs so that electrical charges can neutralize each other. Atoms that are missing electrons combine with atoms that have extra electrons, therefore creating a stable molecule with evenly paired electrons, and the result is a neutral electrical charge.

      A free radical, however, has an extra electron, creating a negative (−) charge. Because of this unbalanced electrical energy, the free radical tends to attach itself to other molecules in order to obtain a matching electron and attain electrical equilibrium. Some scientists speak of the free radicals as “thieves,” which break up the normal pairing of electrons in neighboring molecules in order to steal a new electron for themselves. This leads to the creation of more free radicals and extensive body damage mainly to the cell membranes, as well as to genetic material. Free radicals, however, are important as a normal aspect of healthy body status: without free radical activity, the body would not be able to produce energy, maintain immunity, use hormones or even contract muscles. This electrical production within the body enables the body to perform these key functions. This key quantity of electricity comes from the unbalanced electron activity of free radicals.

      The most significant targets of free radical damage are cell membranes, DNA and RNA. Damage to nuclear DNA can result in faulty copies during cell reproduction and damage to mitochondrial DNA; this in turn results in a decrease in energy production, which is essential for running the nuclear genetic machinery necessary to make proteins, enzymes and even hormones.

      Free radical damage begins at birth and continues until death. Early in life, its effects are relatively minor because the body has extensive repair and replacement mechanisms in place that allow the cells and organs to work optimally. Over time, however, the accumulative effects of free radical damage begin to take their toll.

      Cosmetic surgeons and physicians are used to seeing the effects of free radical damage on collagen and elastin, the substance that keeps skin smooth, moist, flexible and elastic. The most obvious effects of free radical damage occur in the skin in the forms of deep wrinkles, loss of elastic properties of muscle and a decrease in the content of facial fat.

      One of the key components of anti-aging therapy is to prescribe and create a host of natural and manufactured antioxidants to help combat the effects of aging. The body possesses an inherent ability to produce intrinsic antioxidants, the most common ones being superoxide dismutase, catalase and glutathione peroxidase. These are produced and stored mainly at the intracellular level of the mitochondria, which is another key focus of anti-aging therapy.

      Waste Accumulation Theory According to this theory, cells produce more waste than they can properly dispose of. This waste may include many different toxins, which accumulate in the cell and therefore interfere with normal cell function, ultimately killing the cells. Results of a great deal of new research support this theory, especially with regard to the production of a waste product called lipofuscin. This compound is frequently found in the nerve and heart cells. Lipofuscin is formed by a complex reaction that binds fat and proteins within the cells.

      Membrane Hypothesis of Aging^2,3 A recent elaboration on the waste accumulation theory is this hypothesis (Diagram II-2), which was popularized by Dr. Imre Zs-Nagy.² In this theory, free radicals damage the cell membrane, and it becomes unable to let nutrients in and waste products out. Waste products focused on in this theory include lipofuscin and cellular salts in the form of potassium, which build up within the cell, causing the cell to become

Скачать книгу