TLR4 and intervertebral disk degenerative disorder: Hypoxia-induced miR-17-5p enrichment in MSCs-sEVs, which in turn regulated the proliferation and synthesis of myeloid cell (NPC) stroma through the TLR4/PI3K/AKT pathway of the downstream target gene TLR4 for the treatment of intervertebral disc degeneration (IDD) [241].