Espresso coffee may prevent Alzheimer's symptoms, lab study finds

Compounds in espresso coffee may inhibit a process that is believed to be involved in the onset of Alzheimer's disease, according to early findings of a study conducted in lab.

To make espresso coffee, hot water is forced through finely ground coffee beans, creating a concentrated extract. This is often used as a base for other drinks, including the trendy espresso martini.

Recent research has suggested that coffee could also have beneficial effects against certain neurodegenerative diseases, including Alzheimer's disease.

In healthy people, tau proteins help stabilise structures in the brain, but when certain diseases develop, the proteins can clump together into fibrils -- a process that is believed to be involved in the onset of Alzheimer's.

The study, published in the Journal of Agricultural and Food Chemistry, nalaysed if compounds in espresso could prevent tau aggregation in vitro.

Researchers from the University of Verona in Italy pulled espresso shots from store-bought beans, then characterised their chemical makeup using nuclear magnetic resonance spectroscopy.

They chose caffeine and trigonelline, both alkaloids, the flavonoid genistein and theobromine, a compound also found in chocolate, to focus on in further experiments.

These molecules, along with the complete espresso extract, were incubated alongside a shortened form of the tau protein for up to 40 hours.

As the concentration of espresso extract, caffeine or genistein increased, tau fibrils were shorter and didn't form larger sheets, with the complete extract showing the most dramatic results.

Shortened fibrils were found to be non-toxic to cells, and they did not act as "seeds" for further aggregation. In other experiments, the researchers observed that caffeine and the espresso extract could both bind pre-formed tau fibrils.

Although much more research is needed, the team says its preliminary findings could pave the way towards designing other bioactive compounds against neurodegenerative diseases.