Electroacupuncture inhibits annulus fibrosis cell apoptosis in vivo via TNF-α-TNFR1-caspase-8 and integrin β1/Akt signaling pathways

OBJECTIVE: To examine whether electroacupuncture(EA) treatment inhibited cell apoptosis of intervertebral annulus fibrosis(AF) via tumor necrosis factor-α(TNF-α)-tumor necrosis factor receptor 1(TNFR1)-caspase-8 and integrin β1/Akt signaling pathways in a rat model of cervical intervertebral disc degeneration caused by unbalanced dynamic and static forces.METHODS: Thirty-two Sprague-Dawley rats were included in this study, of which 24 rats underwent surgery to induce cervical intervertebral disc degeneration, while eight rats received EA treatment at Dazhui(GV 14). Immunohistochemical staining was used to detect TNF-α, TNFR1, and caspase-8Apoptosis of AF cells was examined with terminal deoxynucleotidyl transferase-mediated d UTP-biotin nick end labeling(TUNEL) staining. The m RNA and protein expression levels of integrin β1 andAkt were evaluated with real-time polymerase chain reaction and western blot analysis, respectively.RESULTS: Treatment with EA decreased TUNEL-positive AF cells and lowered TNF-α, TNFR1 and caspase-8 positive cells compared with control groups. EA treatment also increased integrin β1and Akt m RNA and protein levels compared with controls.CONCLUSION: Treatment with EA inhibits AF cell apoptosis through suppression of the TNF-α-TNFR1-caspase-8 signal pathway and increases the expression of integrin β1 and Akt. EA may be a good alternative therapy for treating cervical spondylosis.