Osteoarthritis is a chronic inflammatory disease that leads to joint pain and disability in both humans and horses. Competition horses develop the disease very early as a result of intensive training at a young age. As part of a large collaborative project between the Swedish University of Agricultural Sciences (SLU) and Sahlgrenska University Hospital (SU), researchers at Chalmers have been involved in developing a new method to enable early diagnosis of osteoarthritis in horses.
“Osteoarthritis is a chronic joint inflammation where the disease process is slow and difficult to diagnose at an early stage. But to be able to treat it, it is important to identify the early stages”, says Eva Skiöldebrand, professor of general pathology at the Swedish University of Agricultural Sciences (SLU) with a focus on osteoarthritis in horses and humans.
“Together with professors Stina Ekman at SLU and Anders Lindahl at SU, our research group has developed biomarkers, or more specifically, identified new neoepitopes* that are generated when protein from articular cartilage and underlying subchondral bone (bone under articular cartilage) is broken down by inflammation, which is the hallmark of the disease. The research group has been able to verify the biomarkers in serum and synovial fluid in horses with varying degrees of osteoarthritis and studied the effect of training and the effect of circadian rhythm, which is a major research breakthrough, says Eva Skiöldebrand.
The use of biomarkers allows the disease to be detected earlier and the occurrence of serious injuries to be prevented – and the effectiveness of drugs for the treatment of osteoarthritis can be evaluated.
Early diagnosis with saliva test
One person who has played a large part in a related research breakthrough at the end of 2021 is Moa Lord, a former biotechnology student and now a research assistant in materials physics at Chalmers. Together with the research group at SLU and SU, she has developed a new method for quantifying biomarkers in saliva in horses, under the supervision of professor Eva Skiöldebrand, Susanne Nyström, PhD in molecular biology, BMA at SU, and Magnus Karlsteen, associate professor of materials physics at Chalmers and responsible for Chalmers' initiatives in equine technology.
“We wanted to develop a method that could easily fit into the daily horse keeping. Saliva sampling is a non-invasive sampling method in contrast to synovial fluid samples and blood samples, which means that you can take more samples without creating discomfort in the horse. Detection and quantification of the biomarker in saliva enables an easier way to monitor how the biomarker is affected by training and surfaces, and detection of early signs of disease”, says Moa Lord.
Self-developed bit for horses
To facilitate saliva sampling, Chalmers has refined the method by producing a special bit for horses.
“When we discovered that we could use saliva to measure the biomarker, we wanted to investigate how the biomarker changes during a training session when the strain on the joint increases. That is why we at Chalmers have designed and constructed a bit with space for sampling tubes. The bit collects the saliva while riding or driving the horse. This enables us to collect samples in a simpler way and that the training session can be completed without a major interruption to take a sample”, says Moa Lord.
“This bit and the ability to detect the biomarker in saliva is the basis for a completely new diagnostic method, there is no one who has done something similar before. The current test tubes in the saliva collection bit work well. But we are working for the long-term goal of implementing an electronic graphen sensor e in the bit, which can provide continuous measurement values of the biomarker and test results directly on site. This would enable the horse owner from home to consult with a veterinarian and follow the development of the disease and act by working preventively to eliminate incipient disease”, says Magnus Karlsteen.
“Considering that a large number of competition horses develop osteoarthritis, the bit is important for the preventive work. Being able to measure the biomarker in saliva means that we can measure the effect of training when the horse runs and rides on different surfaces and at different paces. Then you can tailor training programs that will not harm the joints and hopefully it can result in fewer horses developing the disease”, says Eva Skiöldebrand.
Continued funding of the project
Moa Lord’s project "Can we use saliva to detect osteoarthritis in the horse?" has been part-financed by the Health Engineering Area of Advance at Chalmers. At the beginning of 2022, The Swedish Association for the Protection of Animals granted funding to investigate the presence of pain biomarkers in the saliva of horses. “The presence of pain biomarkers in saliva can provide an enormous amount of information about the horse's pain status and we are incredibly grateful for this research money”, says Eva Skiöldebrand.
“The success of this research project is fantastically gratifying and hopeful for the diagnosis and prevention of osteoarthritis in horses, but also in humans in the future”, says Martin Fagerström, Co-Director of Health Engineering Area of Advance at Chalmers.
Joint commitment to horse welfare
The collaboration between Eva Skiöldebrand, SLU, and Magnus Karlsteen and Moa Lord at Chalmers has, among other things, its background in a common interest in equestrian sports and a strong commitment to horse welfare. Their paths have, among other things, been crossed at the Chalmers fence, an event in connection with the World Cup competitions in horse jumping in Gothenburg, with Magnus Karlsteen as responsible.
Reinforced focus on sports technology
According to the International Horse Sports Confederation, Chalmers is world leading in equestrian technology.
From 1 August 2022, Chalmers will be the first national sports university in Sweden to become a competence centre for sports technology. This means enhanced cooperation between the sports movement and the various specialist sports federations in Sweden.
* Neoepitope is a fragment created by cleavage of protein on a specific amino acid sequence.
- Associate Professor, Materials Physics, Physics