Zebrafish (Danio rerio), known for its extraordinary ability to mend its own heart, may now help in developing treatments for different genetic disorders.
Researchers from the University of Sheffield have developed new treatments for Charcot Marie Tooth (CMT), a genetic disorder that affects more than 20,000 people in US alone, with the aid of a zebrafish.
Charcot Marie Tooth is a condition causing long-term progressive pain in the feet followed by extreme weakness and walking difficulties. Though there is no cure available as yet to treat this genetic disorder, scientists assure that it's about to change, thanks to the zebrafish.
"We have studied zebrafish with a genetic defect that causes CMT in humans. The fish develop normally, but once they reach adulthood they start to develop difficulties swimming," Dr Andrew Grierson, who led the study, explained.
"By looking at the muscles of these fish we have discovered that the problem lies with the connections between motor neurons and muscle, which are known to be essential for walking in humans and also swimming in fish."
A good majority of distal axon degeneration cases, caused due to CMT, are caused due to a mutation in an essential gene (mitofusin 2), which holds a protein responsible for the correct fusion of the mitochondrial membrane.
"Previous work on this disorder using mammalian models such as mice has been problematic, because the mitofusin genes are essential for embryonic development. Using zebrafish we were able to develop a model with an adult onset, progressive phenotype with predominant symptoms of motor dysfunction similar to CMT2," Dr Grierson added.
Since motor neurons are the largest cells in the human body, they are extremely dependant on a cellular transport system for the delivery of molecules through long cell processes.
"We already know that defects in the cellular transport system occur early in the development of diseases such as Alzheimer's disease, Motor Neuron Disease and spastic paraplegia. Using our zebrafish model we have found that similar defects in transport are also a key part of the disease process in CMT," Dr Grierson concluded.
Furthermore, zebrafish are ideal experimental sources owing to their size and unique biology, and further studies may help scientists develop new therapies to treat untreatable health conditions in humans.
The study is published in the journal PLOS ONE.