Why do we use naked mole-rats?
The naked mole-rat is a mammal with a truly bizarre appearance, looking like an elongated cocktail sausage with large, protruding teeth. Naked mole-rats live in large underground colonies of approximately 80 animals, which are dominated by a single breeding female, the queen; this social system is highly unusual in mammals but is similar to that commonly observed in bees and termites. Unlike queen bees and termites that use pheromones to control colony behaviour, a naked mole-rat queen uses aggression, being the physically dominant animal in a colony.
Over the last decade further physiological peculiarities of naked mole-rat physiology have come to light:
- Extreme longevity – naked mole-rats live until 30 years of age, whereas the longevity of similarly sized mice is two to three years; moreover, naked mole-rats display sustained good health into old age and unlike most mammals do not display an increased incidence of death with ageing
- Cancer resistance – naked mole-rats do not spontaneously develop cancer
- Insensitivity to acid as a noxious stimulus – naked mole-rats respond normally to mechanical and thermal stimuli, but fail to perceive acid as noxious
- Hypoxia resistance – naked mole-rat brain tissue can withstand sustained periods of hypoxia (low oxygen levels) and even anoxia (no oxygen).
What do we study?
In 2014, scientists from the Department of Pharmacology established the University of Cambridge Naked Mole-Rat Initiative, which aims to bring together experts in different scientific areas with the overarching aim being to identify molecular explanations for the highly unusual physiology of this species.
An example of previous success in this area comes from a study by Dr Ewan St John Smith, a founding member of the initiative, which identified the molecular basis of naked mole-rat acid-insensitivity.
More recently Dr Smith was part of a study that demonstrated that naked mole-rats are highly resistant to hypoxia and anoxia due to their cells being able to efficiently utilise fructose to power energy production during periods of low oxygen. This work enhances understanding of how nerve cells can function in the absence of oxygen and might lead to work that uncovers novel treatments to prevent brain damage in stroke patients.