Background to research

Skeletal conditions, such as the joint disorder osteoarthritis and the bone fragility disease osteoporosis, affect tens of millions of people in the UK and are becoming more common as a result of an ageing population. Both cause reduced quality of life for sufferers.

Historically, studies in the field of bone disease development and trials for new treatments had been performed in either rodents or sometimes dogs. It was previously unknown whether fish, who are supported by the water in which they swim and appear to experience less discomfort from skeletal changes, could really model the complex cellular, genetic and mechanical aspects of osteoarthritis and osteoporosis.

Studies performed

Professor Chrissy Hammond and her team investigated whether zebrafish naturally developed osteoarthritis and osteoporosis as they aged. As zebrafish are semi-translucent, researchers were able to perform non-invasive observations into how the bone and cartilage cells in the skeletal responded to ageing, and to treatment with pharmaceuticals that increase or decrease bone.  

Using micro-computed tomography (CAT scans) they studied how bone shapes and density are altered if fish carry disease genes. Utilising the same computer modelling techniques used by engineers to test how well materials perform when loaded, Hammond’s team tested on a computer (rather than on the fish) how resistant these bones are to fractures, and how well the joints can move.

Research impact

The studies showed that zebrafish carrying genetic changes that, when present in humans lead to osteoarthritis or osteoporosis, develop the conditions in the same way that human patience and rodents do, and further, that zebrafish show the same changes as mammalian models in response both to pharmaceuticals that alter the skeleton. This means that we can model these conditions, and test new treatments in fish, and even on scales from these fish, rather than in mice or on dogs. Performing these studies has led to more than 40 other groups worldwide switching from performing invasive studies in mice to less invasive studies in zebrafish.

Their group are currently looking at ways to improve bone health in children who have had chemotherapy and looking for new candidate medicines to treat severe osteoporosis.