Serum keratan sulfate transiently increases in the early stage of osteoarthritis during strenuous running of rats: protective effect of intraarticular hyaluronan injection

Introduction Osteoarthritis is influenced by genetic and environment factors, including mechanical stress; however, the relationship between running and the development of osteoarthritis remains a matter of controversy. We investigated whether osteoarthritic change could be obtained in a rat strenuous running model, whether serum keratan sulfate in rats could be detected by HPLC and was associated with onset or progression of osteoarthritis, and whether hyaluronan injection suppressed development of osteoarthritis and elevation of serum keratan sulfate.