Free radicals are intermediates in many normal and necessary metabolic reactions. Thus, all oxygen-using organisms have had to evolve defensive mechanisms against free radicals: The enzymes catalase and peroxidase break down hydrogen peroxide and other peroxides, superoxide dismutase (called SOD) controls the superoxide free radical, and glutathione peroxidase also controls peroxides. Antioxidants such as vitamins […]
where: R is an organic molecule ROOH is an organic peroxide R:R are two organic molecules which have been cross-linked to- gether Oz is oxygen Cu is copper, Fe is iron *is the unpaired electron H is a hydrogen atom HO* is a superoxide free radical RO,* and R* are organic free radicals Note that […]
Empiricism may serve to accumulate facts, but it will never build science. The experimenter who does not know what he is looking for will not understand what he finds. —Claude Bernard, 1813-1878 When your skin wrinkles, or arteries or bread hardens, or rubber becomes brittle, or old Jell-O® stiffens, we are seeing examples of the […]
Read more Cross-linked Molecules and Aging in Skin, Arteries, and Other Tissues I
… just as the pigment of the hair is destroyed by phagocytes, so also the atrophy of other organs of the body, in old age, is very frequently due to the action of devouring cells which I have called macrophages. —Elie Metchnikoff, The Prolongation of Life (1908) Instead of preventing diseases only by protecting the […]
The production of slightly different versions of enzymes and hormones might also lead to autoimmune disease, since the immune system might identify some of these versions as foreign proteins and subsequently launch a self-destructive attack on the body’s own cells which produce them. Dr. W. Donner Denckla thinks that part of the death genes’ process […]
Old age must be resisted and its deficiencies supplied. —Cicero We know that as we grow older, our chances of continued survival decline. How does aging kill us? The answers to this question lead directly to the big payoff—how to slow or partially reverse these deadly processes. The accumulated result of the unrepaired or imperfectly […]
Some people try to achieve immortality through their offspring or their works. I prefer to achieve immortality by not dying. —Woody Allen In order to decide intelligently between different possible life extension methods, you require knowledge of the benefits and the costs of a range of life extension choices. Benefit-versus-cost information is ultimately judged in […]
“I mean,” she [Alice] said, “that one can’t help growing older.” “One can’t, perhaps,” said Humpty Dumpty, “but two can. With proper assistance, you might have left off at seven.” —Lewis Carroll, Alice in Wonderland Although conceptions of aging differ among lay persons and even among scientists, we all know that aging accelerates as time […]
There are several aging mechanisms that attack different functions of the body at different rates, leading to impaired health and a decreased probability of surviving as the years progress. The activities of the general population are not good indications of when and how you can extend your life and at what cost. An increased risk […]