TNF and intervertebral disk degenerative disorder: With regards to the IVD, both human and rat NP cells expressed C/EBPβ, and C/EBPβ acts as a potent proinflammatory mediator by inducing the TNFα expression levels via the ERK1/2 and p38 pathways in rat NP cells in IDD (Hiyama et al., 2016).