Horses, like humans, can suffer from joint diseases such as Osteoarthritis (OA) and Osteochondritis dissecans (OCD), which can lead to pain and lameness. Currently, diagnosing these conditions early is challenging, and there’s no treatment that can reverse the damage.

In a pathfinding study, Ontario Veterinary College (OVC) researchers are investigating tiny molecules called microRNAs (miRNAs) present in blood and joint fluid. What they are finding is that certain miRNAs could be used to predict the onset of joint diseases, potentially leading to earlier and more effective treatments.

Not only could micoRNAs be early predictors of OA and OCD but there is excitement over the potential for them to play a role in targeting new treatments. These molecules can influence various biological processes such as regulating inflammation, cartilage decay, cell death in cartilage, and changes in the extracellular matrix.

In this ground-breaking study, OVC researchers collected blood and joint fluid from horses with OA and OCD, as well as healthy horses. Analysis of these samples revealed differences in miRNA levels between horses with healthy and diseased joints. They found 57 different miRNAs in OA plasma, 45 in OCD plasma, and 21 between OA and OCD plasma. One miRNA (miR-140-5p) was found in higher amounts in the joint fluid of horses with OA.

Other studies suggest miR-140 are associated with good joint health, with its presence being linked to a slower worsening of the condition in joints affected by OA. Although mir-140 are traditionally thought to be a protective miRNA, this new study hypothesises it may be over expressed in early joint disease in an attempt to save the joint before joint disease can progress further.

This over expression may help detect OA before it causes noticeable problems.

Osteoarthritis is common in athletic and older horses and can be career ending once joint components begin to break down and cycles of inflammation begin.

Future research with larger cohorts is needed to confirm miRNAs as biomarkers but these preliminary findings are exciting researchers because miRNAs could be used to detect joint diseases early and target new treatments paving the way for advances in how we manage joint health!

Click here to read the scientific paper, "microRNAs are differentially expressed in equine plasma of horses with osteoarthritis and osteochondritis dissecans versus control horses."

(Equine Guelph; Photo of horse not associated with study)