Following a talk I recently had at school on UCAS applications as I start to think about applying to university, an interesting point was raised as a side topic by our guest speaker. He mentioned that zebrafish, a fish of no economic value to commercial fisheries, might help to extend our generations’ lifetime by almost 20 years.
The zebrafish is a special animal to biologists because its body is transparent. Therefore zebrafish are transparent early in their life cycle, so it is easy for researchers to see their hearts and blood vessels grow. Their hearts begin to develop after just 12 hours, and they reach adult size – about 3cm long – in about three months. They can provide research results barely three days later. If researchers modify the fish’s genotype at the egg stage, they can see a change in organ shape or dynamics very quickly.
In this 30-hour-old zebrafish embryo, you can observe developing organs like the retina (R), the brain (B), spinal chord (SC), the muscle (M) and the heart (H).
Heart tissue damage may occur when a person has suffered from a heart attack which affects their quality of life. Understanding what proteins allow human heart cells to multiply and regenerate, as they do in these fish, could help develop drugs that help our hearts to heal themselves.
If a person has a heart attack, the heart tissue lacks blood and therefore oxygen, causing it to become damaged or dead. Zebrafish can repair their hearts, unlike humans – heart muscle cells near the damaged area lose their muscle properties and revert back to stem cells. Scientists know that a protein called Mef2 is needed to turn zebrafish stem cells into heart muscle cells.
Dr Yaniv Hinits and colleagues believe that zebrafish muscle cells near wounds are able to turn Mef2 on and off – turning Mef2 off to revert to stem cells, before growing and turning Mef2 back on to repair the heart. Their team has been awarded a grant to find out if controlling Mef2could be used to treat damaged human heart tissue. They will study Mef2 in detail, find out if it can heal the heart after injury, and test if other proteins thought to influence recovery after heart attack are working through Mef2.
From my understanding, the grant was for three years and started 1st July 2014. I hope we hear some results in a few months time from this promising experiment.