With the estimated cost of researching and developing a new drug in excess of £600,000, finding new treatments for human diseases is a huge challenge. Zebrafish offer a unique advantage over biochemical and cell based (in vitro) assessments of chemical compounds. By looking at how a compound acts in a whole organism (in vivo) we can understand better its potential pitfalls as a potential treatment as well as the broader range of action it may have.
Using the various disease models we have developed at The Bateson Centre, we have begun screening libraries of novel compounds and known drugs for new therapeutic uses. Re-screening drugs that are already in use for other diseases is called re-profiling. It is common for a drug to affect more than just the disease or symptom it is targeting. For example, aspirin has been used as a pain reliever for over a hundred years, but towards the end of the 20th Century its ability to thin blood was discovered, and it is now widely used to prevent heart attacks, strokes and blood clots.
Finding new targets for well-established drugs is more cost effective and faster than developing new treatments from scratch. However, we also are looking at completely novel chemicals as the effectiveness and general toxicity of a drug can be examined simultaneously in a zebrafish embryo.
The embryo’s small size allows very small amounts of drug to be looked at in plates that have many small wells (called microtitre plates). We can add the drugs directly to the water, most are small molecules, which includes peptides, dyes and drugs, which can freely diffuse into the zebrafish embryos.
We are developing new ways of automating the process in collaboration with academic labs and industry, including robots that place the embryos into the wells, add the chemicals, or take pictures of the embryos.
We believe that screening chemicals for therapeutic use in zebrafish embryos will lead to the rapid identification of new uses for existing drugs and the discovery of potential novel therapies that can be taken forward for further testing.