Polyamines against senile dementia
Memory loss in old age was prevented by cadaveric poison
In a series of experiments on fruit flies, researchers demonstrated not only this effect itself, but also found that polyamines, products of putrefactive decomposition of proteins, are ways to improve memory in old age. Details with reference to the publication of scientists in Nature Neuroscience (Gupta et al., Restoring polyamines protects from age-induced memory impairment in an autophagy-dependent manner) are given by Nature news: Common nutrient keeps flies sharp into old age. Polyamines reverse age-related memory decline.
The scientists' experiments were planned taking into account previously obtained data on the role of autophagy in the aging process. A number of previous studies have shown that with age, the process of digestion by cells of superfluous structures (and sometimes themselves) slows down, and the stimulation of autophagy leads to an increase in life expectancy at least in nematodes Caenorhabditis elegans and drosophila. Scientists already knew that adding polyamines to invertebrate animal feed also increases life expectancy, but they had no data on whether there is a link between polyamines, life expectancy, autophagy and memory work.
Scientists have demonstrated that the addition of spermidine and putrescine, two polyamines, to the diet of fruit flies prevents memory deterioration with age. The effect of substances on memory in flies was revealed in experiments where conditioned reflexes were formed in insects, combining a certain smell with a weak but unpleasant electric discharge. Such an experimental technique has long become standard when working with invertebrates and it is used not only in experiments with flies, but even in working with more primitive roundworms.
The second experiment with genetically modified fruit flies allowed us to show that the detected effect of polyamines is associated with autophagy. The flies, which initially had a broken mechanism of self-digestion of cells, were not affected by spermidine and putrescine: the addition of polyamines to their diet did not lead to a significant improvement in memory. The third experiment described by scientists was to replace polyamines with ornithine decarboxylase, an enzyme that converts the amino acid ornithine into putrescine: the results were similar to the effects of putrescine itself.
The researchers believe that the results of their experiments can be transferred to humans with some caution. An expert who did not participate in the study, Ronald Davis from the Scripps Research Institute in the USA, believes that the work of his European colleagues opens up new opportunities for the search for nootropic drugs. At the same time, it should be noted that putrescine is a substance that has a sharp unpleasant odor and it is this, along with another polyamine, cadaverine, that is a typical product of putrefactive protein breakdown. The outdated name of putrescine and a number of other diamines is "corpse poison", more than a hundred years ago, fatal poisoning of doctors who opened corpses was associated with it.
Modern studies have shown that both putrescine and other similar diamines play an important role in normal biochemical processes inside a living cell. Despite the fact that in its pure form, putrescine can cause burns when in contact with the skin, it is not so toxic (the lethal dose is only eight times less than that for table salt). Deaths among those who opened corpses are caused by infection with bacteria, and not by the action of polyamines.
Portal "Eternal youth" http://vechnayamolodost.ru02.09.2013