Galectins-1 and-3 Increase in Equine Post-traumatic Osteoarthritis

Area of Science:

• Biochemistry
• Immunology
• Veterinary Medicine

Background:

• Galectins regulate cell functions and are implicated in inflammatory arthritis.
• Galectin-3 is elevated in synovial fluid in some arthritis types, while galectin-1 is considered protective.
• The roles of galectins-1 and -3 in osteoarthritis (OA) are not well understood.

Purpose of the Study:

• To investigate galectin-1 and -3 concentrations and localization in experimental and naturally occurring equine osteoarthritis.
• To assess changes in synovial fluid, synovial membrane, and cartilage following osteochondral injury.
• To measure galectin mRNA expression and protein staining in equine OA models.

Main Methods:

• Quantification of synovial fluid galectin-1 and -3 using ELISAs in experimental and naturally occurring equine OA cohorts.
• Measurement of galectin mRNA expression in synovial membrane and cartilage via RT-qPCR.
• Histochemical assessment of galectin immunostaining in synovial membrane and osteochondral tissues.

Main Results:

• Synovial fluid galectin-1 and -3 concentrations increased after experimental osteochondral fragmentation.
• Cartilage galectin-1 mRNA expression correlated with OA severity in naturally occurring disease.
• Healthy superficial articular cartilage showed strong galectin-3 staining, while galectin-1 staining was minimal; chondrocyte staining increased post-injury.

Conclusions:

• Galectins-1 and -3 are present in healthy equine synovial fluid and their levels rise following post-traumatic osteoarthritis.
• Healthy chondrocytes express galectin-3, with galectin-1 primarily found in chondrones and injured cartilage.
• Further research is required to elucidate the specific functions of galectins-1 and -3 in equine joint health and disease.