title: IL-1β induces apoptosis and autophagy via mitochondria pathway in human degenerative nucleus pulposus cells.
abstract: IL-1β has been reported highly expressed in degenerative intervertebral disc, and our previous study indicated IL-1β facilitates apoptosis of human degenerative nucleus pulposus (NP) cell. However, the underlying molecular mechanism remains unclear. We here demonstrate that IL-1β played a significantly pro-apoptotic effect under serum deprivation. IL-1β decreased Bcl-2/Bax ratio and enhanced cytochrome C released from mitochondria to cytosol, which proved mitochondria-meidated apoptosis was induced. Subsequently, mitochondria damage was detected under IL-1β stimualtion. In addition, IL-1β-mediated injuried mitochondria contributes to activate autophagy. However, pretreatment with the autophagy inhibitor 3-methyladenine showed the potential in further elevating the apoptosis rate induced by IL-1β in NP cells. Our results indicated that the mitochondrial pathway was involved in IL-1β-induced apoptosis of NP cells. Meanwhile, the damaged mitochondria-induced autophagy played a protective role against apoptosis, suggesting a postive feedback mechanism under inflammatory stress.
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Jieliang
authors.initials: J
authors.lastname: Shen
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Shengxi
authors.initials: S
authors.lastname: Xu
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Huzhe
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Hao
authors.affiliation: Department of Orthopaedic Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Zhenming
authors.initials: Z
authors.lastname: Hu
mesh_terms: D017209:Apoptosis; D001343:Autophagy; D045304:Cytochromes c / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000378:metabolism*; D055959:Intervertebral Disc Degeneration / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000473:pathology*; D008928:Mitochondria / Q000378:metabolism*; D000070614:Nucleus Pulposus / Q000473:pathology*
chemical_list: D053583:Interleukin-1beta; D045304:Cytochromes c