IL-1? induces apoptosis and autophagy via mitochondria pathway in human degenerative nucleus pulposus cells.

ABSTRACT: IL-1? has been reported highly expressed in degenerative intervertebral disc, and our previous study indicated IL-1? facilitates apoptosis of human degenerative nucleus pulposus (NP) cell. However, the underlying molecular mechanism remains unclear. We here demonstrate that IL-1? played a significantly pro-apoptotic effect under serum deprivation. IL-1? 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-1? stimualtion. In addition, IL-1?-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-1? in NP cells. Our results indicated that the mitochondrial pathway was involved in IL-1?-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.

SUBMITTER: Shen J 

PROVIDER: S-EPMC5264394 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature