Coffee could be the go-to drug to beat Alzheimer’s disease after research found caffeine has a positive effect on tau deposits in the neurodegenerative disease. 

The research, published in the online edition of Neurobiology of Aging, was based on a two-year project lead by the University of Bonn and the University of Lille, and the researchers believe a new class of drug could now be developed to treat Alzheimer’s disease. 

Tau deposits, along with beta-amyloid plaques, are among the characteristic features of Alzheimer’s disease, which is becoming an increasing problem for the global ageing population. These protein deposits disrupt the communication of the nerve cells in the brain and contribute to their degeneration. 

Caffeine is an adenosine receptor antagonist and is known to block various receptors in the brain that are activated by adenosine, a neuromodulator of the central nervous system and believed to have a role in Alzheimer’s disease. The research team developed an adenosine receptor subtype A2A antagonist similar in form to caffeine, but which was found to be more effective with have fewer side effects. 

Over several weeks the researchers treated genetically engineering mice with an altered tau protein leading to Alzheimer’s symptoms. Compared with a control group receiving a placebo, the animals treated with the A2A antagonist achieved significantly better results on memory tests and particularly spatial memory. Also, an amelioration of the pathogenic processes was demonstrated in the hippocampus, which is the site of memory in rodents.    

"We have taken a good step forward," says Prof. Müller. "The results of the study are truly promising, since we were able to show for the first time that A2A adenosine receptor antagonists actually have very positive effects in an animal model simulating hallmark characteristics and progression of the disease. And the adverse effects are minor."

The researchers now want to test the A2A antagonist in additional animal models. If the results are positive, a clinical study may follow. "Patience is required until A2A adenosine receptor antagonists are approved as new therapeutic agents for Alzheimer's disease. But I am optimistic that clinical studies will be performed," says Prof. Müller.