Effect Of Electro Acupuncture On Apoptosis Of Intervertebral Disc Cells And Wnt/β-catenin In Cervical Spondylosis Model Rats

Objective:This essay aims to observe the effect of electro acupuncture(EA) on apoptosis and Wnt/β-catenin signal pathway in cervical intervertebral disc cells.Methods:A total of 40 SD rats, after being accommodated to the new surroundings for a week, were randomly divided into sham group (n=10, male and female half), and model group (n=30, male and female half). As a control, rats in the sham group received the skin incision, without muscle tissue, and then received skin closure. The model of rat degeneration of cervical intervertebral disc caused by imbalance between the dynamic and static force was established. After 3 months of regular feeding, the toluidine blue staining method was used to verify the success of the model. Then the rats of model group were randomly divided into model control group (control group), model electroacupuncture group (EA group) and model meloxicam treatment group (MT group),8 model rats for each group. The rats of EA group were fixed on the rat fixer, accepted the electroacupuncture at Dazhui,25 min/d,1 time/day, 14 days for 1 course, two courses between interval of 2 d, a total of 2 courses of treatment. The gavage treatment was given to the MT group with the meloxicam tablets of 0.7878mg/kg/d. Rats in the sham group and the model group were just fixed in the same way without any treatment. After the treatment, to the intervertebral disc was taken out. Terminal-deoxynucleoitidyl transferase mediated nick end labeling(Tunel) was used to detect the apoptosis of intervertebral disc cells; the expression of beta-catenin protein was detected by immunohistochemistry; Western-blot was adopted to detect the expression of GSK-3β, Axin and Wnt in intervertebral disc cells.Results:(1) Tunel method:The positive expression number of apoptotic cells in the model group was more than that in the sham group. Small in size, the apoptotic cells were in brown color, different in shape and size. There were less apoptotic cells in the EA group and the MT group than in the control group.(2) Toluidine blue staining:Cartilage endplate in the sham group took on a purple-blue color. The endplate was somewhat thick, and the cartilage cells were in large numbers. In contrast, Cartilage endplate toluidine in the control group took on a light-blue color; the endplate was thinner, and the cartilage cells decreased markedly.(3) Immunohistochemistry (IHC):The contents of Wnt, GSK-3β and Axin in the model group were relatively less than those in the sham group, and their differences were statistically significant(P<0.05). The contents of Wnt, GSK-3β and Axin in the EA group and MT group were relatively increased, larger in number than in the sham group, and their differences were statistically significant(P< 0.05).(4)Western-blot detection:The contents of β-catenin in the model group were relatively decreased, less in number than in the sham group, and their differences were statistically significant (P<0.05). The contents of β-catenin in the EA group and MT group were relatively increased significantly, larger in number than in the sham group, and their differences were statistically significant(P< 0.05).Conclusion:(1) Electroacupuncture at Dazhui point can inhibit the apoptosis of cells in chondrocytes of rats with cervical intervertebral disc degeneration.(2) Electroacupuncture intervention can increase the expression of the Wnt, GSK-3β and Axin in the disc cartilage cells, and regulate the Wnt/β-catenin signaling pathway.(3) EA "Dazhui" point successfully delays the degeneration of cervical intervertebral disc, possibly through inhibiting Wnt/β-catenin signaling pathway, increasing the contents of the Wnt, GSK-3β, Axin and β-catenin in chondrocytes.