IGF1 and intervertebral disk degenerative disorder: The authors showed that icariin treatment promoted the migration of stem cells in IDD by upregulating chemotactic cytokines, such as insulin-like growth factor 1 (IGF-1), transforming growth factor-beta (TGF-β), stromal cell-derived factor-1 (SDF-1), and C-C motif chemokine ligand 5 (CCL-5).