Docosahexaenoic acid alleviates the excessive degradation of extracellular matrix in the nucleus pulposus by reducing the content of lncRNA NEAT1 to prevent the progression of intervertebral disc degeneration.

ABSTRACT

The pathogenesis of intervertebral disc degeneration (IVDD), as a multifactorial disease, has not been fully elucidated. However, damage to the stress-bearing system in the intervertebral disc (IVD) mediated by the excessive decomposition of extracellular matrix (ECM) in nucleus pulposus (NP) cells caused by local stimulation is widely considered the core pathological process underlying IVDD. Docosahexaenoic acid (DHA) plays a protective role in various chronic diseases. However, whether it can have such effects in IVDD has not been clearly reported. In recent years, in-depth research on the role of long non-coding RNA (lncRNA) nuclear-enriched transcript 1 (NEAT1) in various diseases has continuously emerged, but such research in the field of IVD is not sufficient. In this study, tert-butyl hydroperoxide (TBHP) was used to induce oxidative stress in human NP cells and construct a cell model of excessive ECM decomposition in vitro. A plasmid over-expressing lncRNA NEAT1 was introduced into human NP cells to establish an NP cell model. For this specific experiment, Cell Counting Kit 8 was used to explore the timing and concentration of DHA and TBHP activity. A common gene chip platform was also used to select potential lncRNAs. Western blot and immunofluorescence assays were used to detect the expression of ECM-related proteins in NP cells in each group. Quantitative real-time polymerase chain reaction was used to detect the expression of lncRNA NEAT1 in NP cells in each group. On this basis, we proved that DHA alleviates excessive degradation of the ECM in NP cells in response to oxidative stress by reducing the content of lncRNA NEAT1. In conclusion, our study reveals the mechanism through which DHA relieves excessive ECM decomposition in NP cells and provides a potential new idea for the treatment of IVDD in clinical practice.