The 21st Century has brought about many great
scientific advances such as the map of the human genome and the discovery of
the Higgs Boson. Another up and coming scientific discovery involves stem cell
research. In the past ten or so years, scientists have discovered that
vertebrates can produce stem cells. Previously scientists believed that
vertebrates were stuck with the number of stem cells they were born with.
However, if you observe nature, you see that stem cells are generated in adult
animals.
Think of a salamander for example, when faced with a
predator, they “let go” or autonomize a section of their tail in order to
escape danger. Their tail, an extension of their spinal cord, grows back as if
nothing ever happened. Phenomena such as this led to further research in neural
stem cell regeneration of these small amphibians.
Vertebrates experience stem cell generation in their nasal
cavities. Salamanders are especially adept at creating neural stem cells in
their noses. Specifically, they have an area of their nose, called the vomeronasal
organ, where neural stem cells divide extensively. This special organ allows
the salamanders to detect pheromones of other salamanders and determine if
their territory is in danger or if there is a potential mate nearby. They do
this by sticking their noses in fecal pellets and adjust their behavior
accordingly.
Stem cells that help salamanders smell and allows them to
regrow their tails may not seem particularly important. However, through
advances in genomics (the study of genes) scientists know that an evolutionary
relationship exists between amphibians and humans because they share the same
genes in development. For whatever reason, humans are unable to activate the
genes that cause neural stem cell regeneration, at least not as freely as
amphibians can.
Once scientists can determine which gene is responsible for
turning on the stem cell genes in amphibians, they will hopefully be able to
find the homologous gene in humans that has been mostly turned off. If these
stem cells can be turned on in humans they could potentially be transported to
other places in the body such as the brain or spinal cord. This would be a monumental
medical advancement that would help treat everyone from stroke victims, to paraplegics,
to people with Parkinson’s disease and Multiple Sclerosis. Stem cell loss
results in the degradation of the human body and diseases with serious
suffering. The advances we are seeing in salamanders may unlock key mechanisms
that could greatly benefit the human population.
