Effect of "nape seven needles" on expression of hypoxia inducible factor-1α and Notch1 in cervical intervertebral disc degeneration rats

Abstract

To observe the effect of "nape seven needles" on the expressions of hypoxia inducible factor-1α (HIF-1α) and Notch1 in cervical intervertebral disc of cervical disc degeneration (CDD) rats, so as to reveal its underlying mecha-nisms in improving CDD. SD male rats were randomly divided into normal, model, non-acupoint and nape seven needles groups, with 10 rats in each group. Staticdynamic imbalance method was used to establish CDD model. Rats in the nape se-ven needles group were treated with acupuncture at "Fengfu"(GV16), and bilateral "Fengchi"(GB20), "Wangu"(GB12) and "Tianzhu"(BL10), and rats in the non-acupoint group received acupuncture at the sham acupoints at the caudal tip and armpit, both for 20 min, 6 days a week for 4 weeks. After intervention, tilted plane test and spiral CT were used to assess the neck movement function and cervical degeneration degree of rats; immunohistochemistry was used to observe the protein expression levels of HIF-1α and Notch1 in cervical discs tissue; Western blot and real-time quantitative PCR were used to detect the protein and mRNA expression levels of HIF-1α and Notch1 in cervical discs tissue, respectively. After modeling, the cervical curvature was straightened, with narrowed intervertebral space, rough and hardened articular surface, osteophytes, and blurred articular space and articular process, which was relatively milder in the nape seven needles group. Compared with the normal group, the angle of tilted plane was significantly reduced (P<0.05), while cervical scores, HIF-1α mRNA expression level in cervical intervertebral disc tissue were significantly increased (P<0.05) in the model group. Compared with the model and the non-acupoint groups, cervical scores were significantly reduced (P<0.05), while the angle of tilted plane, HIF-1α and Notch1 positive expressions, HIF-1α mRNA expression level, Notch1 protein and mRNA expression levels in cervical intervertebral disc tissue were significantly increased (P<0.05) in the nape seven needles group. Acupuncture of "nape seven needles" can reduce the degree of cervical degeneration in rats, which was possibly associated with its effects in up-regulating the expressions of HIF-1α and Notch1 in cervical intervertebral disc tissue, promoting the proliferation and recovery of endogenous cells in nucleus pulposus.