UCHL1 alleviates nucleus pulposus cell senescence by promoting chaperone-mediated autophagy antagonizing autophagy-dependent ferroptosis through deubiquitination of HSPA8

AAV: adeno-associated virus; AB: Alcian Blue; ACSL4: acyl-CoA synthetase long chain family member 4; ALP: autophagy-lysosome pathway; Baf-A1: bafilomycin A1; CHX: cycloheximide; CMA: chaperone-mediated autophagy; Co-IP: co-immunoprecipitation; DUBs: deubiquitinating enzymes; eMI: endosomal microautophagy; Evs: extracellular vesicles; Exo: exosome; GPX4: glutathione peroxidase 4; H&E: hematoxylin and eosin; HsNPCs: Human NPCs; IF: immunofluorescence; IHC: immunohistochemistry; IP-MS: immunoprecipitation mass spectrometry; IVDD: intervertebral disc degeneration; IVDs: intervertebral discs; LBP: low back pain; LDP: lumbar disc prolapse; MRI: magnetic resonance imaging; N/L: NH4Cl and leupeptin; NP: nucleus pulposus; NPCs: nucleus pulposus cells; PCA: principal component analysis; qRT-PCR: quantitative real-time PCR; RnBMSCs: rat bone marrow mesenchymal stem cells; RnNPCs: rat NPCs; ROS: reactive oxygen species; SA-GLB1/β-gal: senescence-associated galactosidase beta 1; SASP: senescence-associated secretory phenotype; SD: Sprague-Dawley; SO: Safranin O-Fast Green; TBHP: tert-butyl hydroperoxide; UCHL1: ubiquitin C-terminal hydrolase L1; UPS: ubiquitin-proteasome system.