Stroke occurs every 2 seconds worldwide and is the second largest cause of death. When a stroke happens, the most important tissues of our body, the brain and heart, are starved of oxygen causing cell damage. To improve therapies for stroke patients we need to understand how the human body copes without oxygen and one researcher at the University of Cambridge thinks he may have found the answer in the form of a small rodent called a naked mole rat. Dr Ewan St John Smith and his colleagues were able to identify a new mechanism used by the naked mole rats to maintain an energy supply to the cells in their body without using oxygen. He told me more about these fascinating creatures…
- Naked mole rats are the same size as a mouse, are the only cold-blooded mammal that we are currently aware of and they live for over 30 years despite the maths suggesting they should only live between 3-5 years.
- They live underground in large colonies of up to 300 and so have adapted to be able to function normally in a low-oxygen environment.
- A low-level oxygen environment, such as that experienced by the brain when a human suffers a stroke, will kill a mouse, but the naked mole rats are able to survive for 20 minutes without experiencing any side effects.
- The heart rate of the naked mole rats drops to around 20-25% of normal levels during the oxygen deprivation and the question faced by the researchers was where does the energy come from, as it can’t be via the usual method of aerobic respiration with glucose.
- Their findings suggest that the brain and heart cells of the naked mole rats are able to undergo respiration using fructose in their blood, rather than glucose from their cells, and while this also has a limited supply, it does provide a back-up plan to survive the oxygen depletion.
- With this new understanding of how nerve cells function, Ewan and his colleagues hope to be able to develop a similar response in human cells to act as a preventative strategy to stop brain damage during a stroke.
You can listen to the full interview with the Naked Scientists here.
Photo credit: Jedimentat44 on Flickr