Research Paper Volume 12, Issue 23 pp 24242—24254
TNFAIP3 ameliorates the degeneration of inflammatory human nucleus pulposus cells by inhibiting mTOR signaling and promoting autophagy
- 1 Department of Orthopedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
- 2 Laboratory of Skeletal Development and Regeneration, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
Received: May 11, 2020 Accepted: September 4, 2020 Published: November 20, 2020
https://doi.org/10.18632/aging.104160How to Cite
Copyright: © 2020 Chen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Autophagy is involved in degenerative diseases such as osteoarthritis and disc degeneration. Although, tumor necrosis factor α-induced protein 3 (TNFAIP3) is well-known as a key regulator of inflammation and autophagy, it is still not clear whether TNFAIP3 regulates autophagy to protect from human disc cells degeneration. We hypothesize that TNFAIP3 may also regulate autophagy to inhibit pro-inflammatory cytokines expression in human nucleus pulposus cells (NPCs). In this study, TNFAIP3 expression was increased in degenerative disc tissue as well as LPS-stimulated human NPCs, and the effect of TNFAIP3 in LPS-induced NPCs was further explored. The results demonstrated that pro-inflammatory cytokines expression in TNFAIP3-His cells was decreased, while it was increased in TNFAIP3-siRNA cells. Further molecular mechanism research showed that TNFAIP3-siRNA cells enhanced the phosphorylation of mammalian target of rapamycin (mTOR) and inhibited autophagy. Meanwhile, after treatment of TNFAIP3-siRNA cells with the mTOR inhibitor Torin1, the level of autophagy increased and the decrease of extracellular matrix was reversed. In summary, overexpressed TNFAIP3 can promote autophagy and reduce inflammation in LPS-induced human NPCs. Moreover, autophagy triggered by TNFAIP3 can ameliorate the degeneration of inflammatory human NPCs, providing a potential and an attractive therapeutic strategy for degenerative disease.