Hydrogen sulfide regulates autophagy in nucleus pulposus cells under hypoxia.
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ABSTRACT: Objective
Hydrogen sulfide (H2S) has been found to act as an important gasotransmitter to regulate cell activities. This study aimed to investigate the effect of H2S on autophagy of nucleus pulposus (NP) cells under hypoxia and possible mechanism.Materials and methods
NP cells were isolated from rat caudal discs. Cobalt chloride was used to mimic hypoxia, sodium hydrosulfide was used to emulate exogenous H2S and 3-methyladenine was used to block cell autophagy. Cell viability was assessed by phase contrast microscope and Cell Counting Kit-8 method. Moreover, expression of key autophagic proteins was analyzed via western blotting, and transmission electron microscopy was performed to detect autophagosomes.Results
Hypoxia markedly impaired NP cell proliferation compared with control. Whereas H2S provided pro-proliferation and pro-autophagy effects on hypoxic NP cells. However, these beneficial impact of H2S on hypoxic NP cells were reversed by autophagy inhibitor.Conclusions
Our results showed that H2S played a cytoprotective role in NP cells exposed to hypoxia in an autophagy-dependent manner.
SUBMITTER: Yue L
PROVIDER: S-EPMC8717115 | biostudies-literature |
REPOSITORIES: biostudies-literature
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