Research Paper Volume 12, Issue 16 pp 16126—16141
SIRT1 alleviates high-magnitude compression-induced senescence in nucleus pulposus cells via PINK1-dependent mitophagy
- 1 Department of Orthopedics, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
- 2 Tissue Repairing and Biotechnology Research Center, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
- 3 Department of Orthopedics, Three Gorges Central Hospital, Chongqing 404000, China
- 4 Department of Orthopedics, Southwest Hospital, Third Military Medical University, Army Medical University, Chongqing 400038, China
Received: March 3, 2020 Accepted: May 27, 2020 Published: July 18, 2020
https://doi.org/10.18632/aging.103587How to Cite
Copyright © 2020 Wang 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
Mechanical overloading-induced nucleus pulposus (NP) cells senescence plays an important role in the pathogenesis of intervertebral disc degeneration (IVDD). The silent mating type information regulator 2 homolog-1 (SIRT1)-mediated pathway preserves the normal NP cell phenotype and mitochondrial homeostasis under multiple stresses. We aimed to investigate the role of SIRT1 in IVDD by assessing the effects of SIRT1 overexpression on high-magnitude compression-induced senescence in NP cells. High-magnitude compression induced cellular senescence and mitochondrial dysfunction in human NP cells. Moreover, SIRT1 overexpression tended to alleviate NP cell senescence and mitochondrial dysfunction under compressive stress. Given the mitophagy-inducing property of SIRT1, activity of mitophagy was evaluated in NP cells to further demonstrate the underlying mechanism. The results showed that SIRT1-overexpression attenuated senescence and mitochondrial injury in NP cells subjected to high-magnitude compression. However, depletion of PINK1, a key mitophagic regulator, impaired mitophagy and blocked the protective role of SIRT1 against compression induced senescence in NP cells. In summary, these results suggest that SIRT1 plays a protective role in alleviating NP cell senescence and mitochondrial dysfunction under high-magnitude compression, the mechanism of which is associated with the regulation of PINK1-dependent mitophagy. Our findings may provide a potential therapeutic approach for IVDD treatment.