Moracin M inhibits lipopolysaccharide-induced inflammatory responses in nucleus pulposus cells via regulating PI3K/Akt/mTOR phosphorylation

Moracin M, a phenolic component obtained from Mori Cortex, has been reported to have anti-inflammatory activities. The present study was designed to investigate the effects and mechanisms of Moracin M on lipopolysaccharide (LPS)-treated nucleus pulposus cells (NPCs) in intervertebral disc. NPCs were treated with moracin M at different concentrations for 1 h and then stimulated with LPS (0.5 μg/mL) for 24 h. The result demonstrated that moracin M could significantly inhibit LPS-induced inflammation. The elevated levels of IL-1β, TNF-α and IL-6 induced by LPS could be reversed by moracin M in NPCs. Moreover, moracin M increased the expressions of autophagy-related proteins and up-regulated the phosphorylation of PI3K/Akt/mTOR in LPS-treated NPCs. In conclusion, our data demonstrated that moracin M might inhibit LPS-induced PI3K and Akt phosphorylation, which leading to promote the autophagy and inhibit the inflammatory mediator production in NPCs.