Equine gluteal muscle LC-MSMS: Warmblood

Myofibrillar myopathy (MFM) in horses is a late onset disease that affects performance and athleticism. It is characterized by myofibrillar disarray and protein aggregation with no known cause. The objective of this study was to elucidate the molecular drivers of MFM in Warmblood (WB) horses by proteomic profiling (5 MFM WB, 4 non-MFM WB) of gluteal muscle. MFM horses used in this study had a chronic history of poor performance and exercise intolerance as well as accumulation of desmin aggregates in > 4 myofibers per muscle sample. The Equine Neuromuscular Diagnostic Laboratory database at Michigan State University was queried to identify WB horses with snap frozen gluteus medius biopsies available for analysis. Non-MFM control horses were defined as horses with no history of exercise intolerance and no evidence of desmin accumulation or other histopathology in muscle biopsies. Muscle biopsy samples were obtained at rest from horses that had not undertaken strenuous exercise in the preceding 48 hours.