Naked mole-rat (Heterocephalus glaber), aptly nicknamed sand puppy, is an obnoxious looking underground dwelling rodent that look like a slack toothed sausage. Though it has a wrinkly hairless body, tiny eyes and elongated pair of front teeth, this mammal may be holding the secrets of how to overcome or avoid cancer, how to avoid aging, feeling pain and even living in the extrasolar planets. Of late, the naked mole rat has caused serious row among scientists over what might be the naked mole rat most unusual feature, outstanding resistance to cancer.
These burrowing rodents, native to Kenya and horn of Africa, have for many years fascinated medical researchers in many ways. They have surprisingly long lifespans of up to 37 years and have antiaging qualities. They hold the record of the longest living rodents. The reason for their longevity is thought to be related to their ability to substantially reduce their metabolism in response to adverse conditions, and so prevent aging-induced damage from oxidative stress.
They are highly resistant to pain. They do not feel pain when exposed to acid or capsaicin (the active chemical in chilli). They survive for lengthy periods with very limited oxygen level. They survive for at least 5 hours in air that contains only 5% oxygen (man can survive for about 5 - 45 minutes).
The naked mole-rat does not regulate its body temperature in typical mammalian fashion. Their body temperature changes according to the external temperature, rather than carrying out thermoregulation like other mammals. They are thermos-conformers rather than thermos-regulators.
They are also one of the only mammals known to live in highly organised, multigenerational colonies, similar to ants and bees. Though they live in colonies made up of 100 individuals (sometimes they can grow to a 300- strong group), there is only a single female (queen) who breeds and mates with one or two, breeding males. The rest of the colony, of both sexes, have their reproduction suppressed and never ever breed, they are sterile. The small ones tend to act as workers and carry out colony maintenance activities. The larger moles seem to adopt a more defensive role, acting as solders keeping predators, such as snakes, at bay.
They live in complex underground tunnels which have great deal of branching and interconnections, resulting to a colony's total tunnel length of up to 4 kilometers. Tunnels connect nest chambers, toilet areas and food sources. Burrowing is the only way these animals find food, because they do not venture above ground. They are well adapted to their underground existence. They have small eyes, short thin legs. Nevertheless, they are highly proficient at moving underground and can move backward as fast as they can move forward.
Naked mole-rats have a high resistance to tumours. Scientists claim the moles have a potential mechanism that averts cancer, an ‘over-crowding’ gene, p16, which prevents cell division once individual cells come into contact. Scientists have also claimed that the reason naked mole-rats do not get cancer be attributed to an extremely high-molecular natural sugary substance, which is over ‘five times large’ than that in cancer-prone humans and cancer-susceptible laboratory animals. There also claims that the naked mole rats are so good at avoiding cancer because of their way of life.
In Kenya, the naked mole-rats are found in Meru National Park, Tsavo East National Park and Kibwezi area.
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