Zebrafish may hold key to greater understanding of common diseases.

A two-inch stripy fish that spends its life in the tropical freshwater streams might not seem an obvious target for discovering more about what causes type 2 diabetes, prostate cancer and Alzheimer’s, but according to researchers at Queen Mary, University of London, UK, it could be key to revealing important mechanisms involved in the progression of these diseases.

Zebrafish are like the lab rats of the aquatic world – they develop extremely quickly and the transparent embryos can be grown outside the mother’s body, which allows scientists to observe their organs clearly, making them ideal subjects for assessing how certain substances affect our bodies. In this study, researchers were looking at the effects of zinc. An essential mineral, it is utilised by the body for cell growth, the immune system, brain function, and reproduction. Although scientists believe zinc is key to further understanding of type 2 diabetes, prostate cancer and Alzheimer’s, they’re uncertain as to what its role is.

Zebrafish

Using the zebrafish the researchers were able to develop a sensor that picks up areas in the fish’s body where zinc is present, such as the pancreas, for example. If the researchers can show similar results with the same technique on larger animals and humans, it could prove an effective way to fully understand the role of zinc in disease.

A recent study from the University of Michigan, US, indicates that zinc has the potential to prevent the shut down of insulin-producing cells. The same process also hinders the production of harmful processes involved in Alzheimer’s disease. The Michigan researchers are now hoping to find out exactly how zinc interacts with the body’s other molecules to help prevent diseases such as diabetes. Perhaps the zebrafish will prove to be the key that unlocks the secret.

As this mineral can’t be produced by the body, we need to get it from food. It is possible, however, to take too much: an intake of around 11 mg for a male adult and 8 mg for women is ideal. “Protein appears to aid the absorption of zinc, and it’s found in a wide variety of protein foods,” says registered nutritionist Dr Carina Norris, author of The Food Manual. “Lean cuts of beef, venison, turkey and seafood are excellent sources. You can also get it from vegetarian food sources, such as sesame and pumpkin seeds, but phytate compounds, found mainly high-fibre plant-based foods, hinder the absorption of zinc, so it’s harder for vegetarians to take in enough of this mineral, as they generally eat more phytates.”