Clinically relevant intra-articular corticosteroid doses impair equine osteoclast function in vitro

Area of Science:

• Equine orthopedics
• Veterinary pharmacology
• Cell biology

Background:

• Intra-articular corticosteroids are frequently used in equine joint management.
• Their effects on osteoclast activity, crucial for bone remodeling, are not fully understood.
• Understanding these effects is vital for optimizing treatment strategies.

Purpose of the Study:

• To evaluate the in vitro effects of clinically relevant doses of three common intra-articular corticosteroids on equine osteoclasts.
• Specifically, triamcinolone acetonide (TCA), methylprednisolone acetate (MPA), and a betamethasone combination (BM) were assessed.

Main Methods:

• An in vitro controlled laboratory study using equine bone marrow-derived osteoclasts.
• Osteoclasts were cultured alone or on equine bone slices.
• Cultures were treated with TCA, MPA, or BM at specific concentrations, with untreated wells serving as controls.

Main Results:

• Corticosteroids significantly reduced mature osteoclast numbers in pure cultures (MPA, TCA, BM).
• Methylprednisolone acetate (MPA) significantly decreased collagen type I degradation (CTX-I) in osteoclast-bone cultures.
• Triamcinolone acetonide (TCA) significantly reduced TRACP-5b levels, an indicator of osteoclast activity.

Conclusions:

• Clinically relevant doses of TCA, MPA, and BM impact equine osteoclast activity in vitro.
• These findings highlight the potential influence of intra-articular corticosteroids on subchondral bone remodeling.
• This knowledge is crucial for guiding the judicious use of these agents in equine joint disease management.