Wednesday, April 11, 2018


The Role of Evolution

Evolution may not contribute much to solving the Alzheimer's problems although it must have been involved in the selection of genes and functional aspects responsible.  Whether knowing more about the biochemistry of amyloid and tau proteins involved in the plaques and tangles diagnostic for Alzheimer's will lead to successful treatments is uncertain.

Clues about the disease may come from more primitive animals with smaller and less complicated brains.  Finding such clues may require greater knowledge of the process in our own brains.  The pogonophorans live to extreme ages under very adverse conditions of limited food and are presumably much like the ancestors of the animal line leading to vertebrates.  More recent ancestors are more likely to be of value.  I personally think study of diverse human populations for their diet and health parameters may give the best clues to further research.


Because Alzheimer's and/or senile dementia increase in severity and frequency with advancing age, typically beyond the fertile years, the hereditary component thought to be about 40 percent is only indirectly subject to natural selection.  Selection may differ if societies with multi-generational families are compared with societies of smaller two or three generation families.  Such a comparison is not likely to be informative since the shift has been quite recent.  The stress of dealing with the afflicted versus the wisdom of elders without the disease may contribute to a shift in the gene pool of such groups.

Increasing age seems to enable the disease process to advance, whether by increased deposits in the brain or increased neuron death or impaired function.  Life-style changes may help avert disease progress.  Maintaining a social life, physical and mental activity, getting adequate rest, and good nutrition (moderation in quantities, more fruits and vegetables, and reduced animal fats).  An article by Paula Spencer Scott in the April 8 (2018) edition of Parade is accompanied by a list of suggestions including the value of music.

I'm not very good at doing the suggested changes even though I suspect several deceased relatives had the disease at death 80 or fewer years ago.  I thank my spouse for my being alive with some mental function as a result of her efforts to limit my animal fat intake and increase the vegetarian portion of my diet.

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Toxic substances such as DDT and other halogenated hydrocarbons polluting the food chain accumulate in animal fat deposits because they are fat soluble and poorly eliminated in urine,  They may enter the blood stream in greater amounts when fats diminish due to dieting or illness.  At such times the high concentration may cause or increase behavioral aberrations such as depression.  Even people with little fat could experience such problems compounding illness if the little fat they had released its toxic store.
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It may be too early to determine if Facebook and Twitter are adequate for the social component of a healthy lifestyle.  I have minimal exposure to both, but maybe if I increase my blogging it will help.

An afterthought on music.  The article referred to above noted singing is supposed to be a good form of music.  Years ago it was common to gather around someone's piano (or other instrument) and sing together.  When my father was doing physical work in his printshop he was typically whistling the same tune over and over.  He was still fairly alert mentally the year he died when he was 96 years old,  Maybe I will whistle more frequently.  Do you think it will help?

Joe Engemann    Kalamazoo, Michigan       April 11, 2018

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