The author of today's open access commentary is quite prolifically opinionated on the topic of mTOR and its status as a central pillar of programmed aging, particularly the hyperfunction version of programmed aging theories. Nonetheless, he sometimes has interesting things to say, as is the case here on the topic of whether aging is a disease. A great deal of ink has been spilled of late on the question of whether or not aging is a disease. This is the case not because everyone suddenly developed an interest in semantics, but rather because it directly affects the regulation of medical development, and thus the flow of funding to research and the later translation of research results into potential therapies.
Programmed aging is roughly the idea that aging is a process under direct natural selection, rather than the mainstream view of aging as a non-selected consequence of natural selection that operates most strongly in early life. In the latter view, early reproductive success near always wins out over a longer reproductive life span, and thus biological systems that offer early life advantage are selected regardless of whether or not they fall apart later in life. Theorists arguing for programmed aging might appeal to group selection, suggesting that aging helps to dampen population explosions, or suggest that aging allows species to outcompete non-aging rivals as the environment changes over long timescales.
Theorizing on programmed aging has gained in popularity in the past decade or so. New strands of thought, such as the hyperfunction theory of programmed aging, in which aging is ascribed to processes of development failing to shut down and running wild in adults, are emerging that incorporate aspects of both programmed and non-programmed theories of aging. For the causal observer, it is becoming a little hard to keep up, particularly as not everyone seems to be arguing for the same version of a given theory, while all using the same name.
Are menopause, aging, and prostate cancer diseases?
Prostate cancer is an age-related disease. Every man would be diagnosed with prostate cancer, except that most men do not live long enough, dying from other age-related diseases. The frequency of prostate cancer detected by autopsy is 30-fold higher than mortality from prostate cancer so that "more men die with prostate cancer than because of it". The older the man, the higher frequency of autopsy-detected prostate cancer. The frequency of high-grade prostate cancer doubles every ten years.
Atherosclerosis is driven by hyperfunction of numerous cell types, acting locally and distantly. Thus, activation of endothelial cells, smooth muscle cells (SMC), and macrophages contributes to the formation of atherosclerotic plaque. Atherosclerosis originates in childhood and progresses throughout life. It occurs in everyone. It is a hallmark of aging and a "normal disease". Clinical manifestations of atherosclerosis, cardiovascular diseases, are the main causes of death in humans.
Some age-related diseases are so program-like that they are considered to be the norm. Menopause happens in every woman, and therefore it is not commonly viewed as a disease. But atherosclerosis and prostate enlargement (and all age-related diseases) also happen in everyone. One may argue that menopause is not as deadly as cancer. However, it is deadlier than osteoarthritis and Alzheimer's disease. Menopause promotes cardiovascular diseases (CVD), osteoporosis, obesity, type II diabetes, and other diseases.
It is difficult to define a disease, especially an age-related disease. For example, osteoporosis and obesity were not officially recognized as diseases until 1994 and 2013, retrospectively. Whether we define age-related alterations as a disease depends on political, cultural, financial, medical, and social reasons. The main objection to considering age-related diseases such as menopause and presbyopia as diseases is that they happen to everyone. However, disease does not need to be rare to be a disease. For example, everyone may be sick with influenza during their lifetime, but it does not make it any less a disease. Furthermore, no definition of disease includes the requirement that it should not affect everyone.
According to conventional views, aging is a risk factor for developing disease. It is believed that aging can be healthy (without diseases) and that humans can die either from aging or from diseases. It was claimed, "aging should be strongly considered not to be a disease and as such should not be treated." According to hyperfunction theory, aging is not a risk factor, aging is the sum of all age-related diseases. In analogy, the zoo consists of animals and does not exist without animals, but the zoo is not an animal. There is no aging without these diseases. So-called "healthy" aging is slow aging observed in centenarians, who develop diseases later in life. But no centenarian dies from old age, all die from age-related diseases.
View the full article at FightAging
