Cold-Activated Protein May Lead to Alzheimer's Treatment
We have known for many years that cooling the brain by reducing body temperature (hypothermia) can protect it in some types of damage. Now new research published in the January 14th edition of Nature has identified a protein that is activated in response to cold that can prevent loss of connections between brain cells in neurodegenerative disease.
Neurodegenerative disease, of which Alzheimer's is one example, is an umbrella term for a number of conditions that primarily affect the neurons (nerve cells) in the brain and spinal cord. Because neurons do not normally reproduce or replace themselves when they are damaged, either through disease or trauma, the body is unable repair it. To some extent the brain does have the ability to make new pathways but it cannot make up for the loss when a disease continues to destroy neurons on a massive scale.
Researchers headed by Professor Giovanna Mallucci at the Medical Research Council's Toxicology Unit in Leicester, UK., investigated the brain's response to intensive body cooling similar to that seen in hibernating animals. When animals hibernate the core body temperature drops to a point where connections between nerve cells in the brain become inactive. This allows the animal to survive without nutrition for weeks or months at a time. They found that the protective processes normally switched on by cooling were defective in mice with either Alzheimer's disease or prion disease. Scientists believe that by simulating the effects of cooling in mice they have revealed a possible new target for drugs that could protect against neurodegeneration.
When the brain cools a variety of so-called ‘cold-shock’ proteins are produced. This study has shown for the first time that switching on a cold-shock protein called RBM3 can prevent brain cell connection losses. It’s still unclear how the protein affects degeneration and regeneration so the next step is for scientists to unpick the exact mechanisms involved. So, we can perhaps look forward to a time where just as anti-inflammatory drugs bring down our temperature so medication may be found that will mimic the effect of brain cooling, but without the need for ice cube baths!
RBM3 mediates structural plasticity and protective effects of cooling in
Neurodegeneration. Giovanna R. Mallucci et al. Nature (2015) doi:10.1038/nature14142