Polyamines slow down memory loss: learning from the fruit fly
The memory of many people deteriorates in old age. This can be related to an emerging dementia disease. In a series of experiments, researchers from Berlin and Graz have now succeeded in stopping this loss of memory, at least in fruit flies. The key is apparently in a polyamine-rich diet. This can help fruit flies to stop the age-related loss of memory.
Polyamines are important products of cell metabolism for tissue growth. It is still questionable whether these results can also be transferred to humans and must be investigated in further experiments. "The concentration of the body's own polyamine spermidine decreases with age in both flies and humans," explained Stephan Sigrist from the Free University of Berlin.
In the latest issue of the journal "Nature Neuroscience", Sigrist and his colleague Frank Madeo (University of Graz) write that experiments with aging fruit flies that were fed with spermidine slowed down the loss of memory.
The main suspects are clumped proteins. In the study, the flies had to choose between two different smells and remember that one of the smells was associated with a negative consequence - a slight electric shock. "One of the main suspects for age-related dementia are clumped proteins that accumulate in the old brains of flies, mice and humans," says Sigrist.
However, the body's own molecule, spermidine, triggers the cellular cleaning process of autophagy. Autophagy generally clears up cellular waste, including protein aggregates, and leads it to the cellular stomach (lysosomes). "This is an effect that is interestingly also known from fasting," says Sigrist.
The onset of dementia can be delayed. Spermidine is both produced by the body's cells and absorbed through food and occurs in the intestinal flora. For example, wheat seedlings or certain products made from fermented soybeans have high concentrations.
The researchers are now hoping to use spermidine as a dietary supplement to delay the onset of dementia in humans. "Even a slight shift could be a big step for the individual patient as well as for society," says Sigrist. "But there is still a long way to go." Studies with people are now said to have consequences. The researchers now hope that one day the positive effect can also be confirmed in humans. (fr)
Image: Sigrid Rossmann / pixelio.de