Zebrafish in multiple sclerosis research

Our body transmits information throughout the body along neurons. Electrical signals are sent down neuronal axons which are insulated on the outside with myelin to ensure rapid conduction of information. Myelin is a lipid-rich structure which extends from the plasma membrane of glial cells.

Disruption of myelin production leads to devastating neuronal conditions such as multiple sclerosis (MS). Although our body has the ability to repair damaged myelin, in degenerative conditions this process of remyelination fails. As a result, it is of paramount importance to study the molecular and cellular mechanisms that co-ordinate myelin formation in order to understand how loss of myelin progresses to disease development.

In this context, scientists on the EU-funded 'Analysis of myelinated axon development in zebrafish' (ZEBRAFISH MYELIN) project used zebrafish as a model for studying myelin formation. Zebrafish constitute an ideal model due to small size, transparency and rapid development, enabling researchers to observe biological events at high resolution.

Through a series of transgenic animals, scientists were able to manipulate myelination and visualise the outcome. They discovered that individual axons regulate myelin sheath production by oligodendrocytes over a very short time. The research team also successfully elucidated how myelin forms around neuronal axons and identified new genes and regulator molecules of the process of myelination.

The ZEBRAFISH MYELIN project findings have clinical implications as they will improve our understanding of neuronal degeneration in MS, culminating in the identification of novel therapeutic targets. The zebrafish model could also be used for the pharmacological screening of small molecules with therapeutic potential.