ACAN and intervertebral disk degenerative disorder: Consistent with the in vitro findings, intraperitoneal injection of DHE in a spinal instability-induced mouse model in vivo partly ameliorated the loss of disc height, significantly restored the quality of the disc structure, increased histological scores and alleviated the expression of TNF-α, IL-1β and the breakdown of aggrecan in the lumbar disc tissue, all indicative of a protective role of DHE against IDD progression [51].