Concentrations of stromal cell-derived factor-1 in serum, plasma, and synovial fluid of horses with osteochondral injury.

This study explores how concentrations of stromal cell-derived factor-1 (SDF-1) in serum, plasma, and synovial fluid differentiate between untrained, trained, and osteochondral-injured Thoroughbred racehorses. Findings suggest that serum SDF-1 concentrations may be a more sensitive indicator of osteochondral injury and could aid in understanding and treating post-traumatic osteoarthritis.

Research Methods

• The study observed 22 racehorses without osteochondral injury and 37 racehorses with this injury. The horses without osteochondral injury were examined before and after 5 to 6 months of race training.
• Horses with osteochondral injury were those undergoing arthroscopic surgery to remove osteochondral fragments from their carpal or fetlock joints.
• Samples of serum, plasma, and synovial fluid (from the fetlock or carpal joints) were obtained from both sets of horses. These samples were analyzed for SDF-1 concentration using an ELISA technique.

Research Results

• In horses with a fetlock or carpal joint injury, the mean synovial fluid SDF-1 concentrations were significantly higher, and serum SDF-1 concentrations were significantly lower, compared with both untrained and trained horses. This resulted in significantly higher synovial fluid-to-serum SDF-1 ratios in the injured horses.
• There was no notable difference in the concentration of SDF-1 within the synovial fluid of trained and untrained horses.
• Plasma SDF-1 concentrations revealed no significant differences between the three groups (untrained, trained, and injured).
• SDF-1 concentrations in the serum were more sensitive in differentiating osteochondral-injured horses from uninjured ones, compared to measurements of SDF-1 in synovial fluid and plasma.
• In horses with fetlock joint osteochondral injury, serum SDF-1 concentrations were correlated with radiographic and arthroscopic inflammation scores, but not with arthroscopic cartilage scores.

Research Conclusions

• The research’s results suggest that concentrations of SDF-1 in the serum have a higher sensitivity for detecting osteochondral injury in racehorses’ fetlock or carpal joint compared to its concentrations in plasma and synovial fluid.
• Analyzing serum and synovial SDF-1 concentrations in horses with experimentally induced joint injury might help in understanding the onset and progression of post-traumatic osteoarthritis, and be instrumental in evaluating the efficacy of anti-inflammatory treatments.