Early Mice Study Says Caffeine Useful in Alzheimer's Disease
There is new research from the US and Japan which shows some benefit of caffeine reversing symptoms of Alzheimer’s disease in aged mice. Keep in mind this linking of caffeine and Alzheimer's disease is early research done in mice not humans.
The research is the work of scientists from the Florida Alzheimer's Disease Research Center (ADRC) at the University of South Florida and colleagues from other research centers in the US and the Saitama Medical University in Japan. Their results are published in the July issue of the Journal of Alzheimer's Disease.
Dr Gary Arendash and colleagues used 55 transgenic mice that had been genetically altered to develop symptoms of Alzheimer's disease. Behaviour tests revealed signs of memory impairment in the mice when they reached 18 to 19 months old which is equivalent to 70 in humans. The 55 mice were divided into two groups: one received caffeine in their drinking water and the other continued with plain drinking water.
The caffeine group was given 500 mg of caffeine a day. It takes five cups of regular coffee or 14 cups of tea or 20 soft drinks to equal 500 mg of caffeine.
After two months (which would be almost 4 years in humans), the mice in the caffeine group did better on memory and thinking tests, and performed as well as mice of the same age without dementia. The mice who only drank plain water continued to do poorly in the tests.
The brains of the mice in the caffeine group were found to have nearly 50% less beta-amyloid than the control mice. Arendash and colleagues suggest that the memory is restored because caffeine appears to reduce both of the enzymes needed to produce beta-amyloid protein ( beta-secretase or BACE1, and presenilin 1 or PS1/g-secretase). The researchers state that another reason could be that caffeine inhibits inflammation that causes too much beta-amyloid to be made.
Arenbash and colleagues hope to start trials in humans to see if caffeine helps people with mild cognitive impairment or early Alzheimer's disease. Caffeine is a safe drug for most people though people with high blood pressure and pregnant women need to be careful with their intake.
Alzheimer's disease affects nearly half of Americans over the age of 85. If these findings hold true for humans, it will be helpful for many.
Caffeine Reverses Cognitive Impairment and Decreases Brain Amyloid-β Levels in Aged Alzheimer's Disease Mice; Journal of Alzheimer's Disease, Volume 17:3 (July 2009); Gary W Arendash, Takashi Mori, Chuanhai Cao, Malgorzata Mamcarz, Melissa Runfeldt, Alexander Dickson, Kavon Rezai-Zadeh, Jun Tan, Bruce A Citron, Xiaoyang Lin, Valentina Echeverria, and Huntington Potter
Caffeine Suppresses Amyloid-β Levels in Plasma and Brain of Alzheimer's Disease Transgenic Mice; Journal of Alzheimer's Disease, Volume 17:3 (July 2009); Chuanhai Cao, John R Cirrito, Xiaoyang Lin, Lilly Wang, Deborah K Verges, Alexander Dickson, Malgorzata Mamcarz, Chi Zhang, Takashi Mori, Gary W Arendash, David M Holzman, and Huntington Potter