The autophagy of rat intervertebral disc nucleus pulposus cells and oxidative stress-induced injury in rat

English Keywords:Angelica  Nucleus pulposus cells  Oxidative stress  Apoptosis  Autophagy

English Abstract:

  【Abstract】 Objectives: To investigate the protective effect of angelica on intervertebral disc nucleus pulposus cells from oxidative stress-induced injury, and to explore its potential mechanism. Methods: Nucleus pulposus cells were isolated from rat lumbar discs and cultured into the third-passage to do the following experiments. The cells were incubated with different concentrations of angelica solution injection(0.1mg/ml, 1mg/ml, 5mg/ml), and the optimum concentration of angelica was detected by MTT. After that, the cultured nucleus pulposus cells were randomly divided into group A, group B and group C. The cells in group B were stimulated with 400μmol/L H2O2 for 0.5h, 1.5h and 3h. And the cells in group C were pretreated with proper concentration of angelica for 24h and then stimulated by 400μmol/L H2O2 for 0.5h, 1.5h and 3h, respectively. The cells in control group were treated with saline for appropriate times. The apoptosis of nucleus pulposus cells was determined by flow cytometry. The expressions of cytochrome C, Bcl-2, Bax, LC3-Ⅱ/Ⅰ, p62, p-AKT, p-mTOR and p-p70S6K were analyzed by western blot. Results: Compared with other concentrations of angelica, 1mg/ml of angelica significantly increased the cell viability(P<0.05). Compared with the cells in group A, apoptosis, expression of cytochrome C and the ratio of LC3-Ⅱ/Ⅰ of the cells in group B were increased(P<0.05), while the ratio of Bcl-2/Bax and the expressions of p62, p-AKT, p-mTOR and p-p70S6K were decreased(P<0.05); compared with the cells in group B, apoptosis and the expressions of cytochrome C, p62, p-AKT, p-mTOR and p-p70S6K of the cells in group C were reduced(P<0.05), while the ratios of Bcl-2/Bax and LC3-Ⅱ/Ⅰwere raised in those of group C(P<0.05). Conclusions: 1mg/ml of angelica solution injection can decrease the apoptosis of nucleus pulposus cell, which may be related to suppression of the mitochondrial pathway. It also can enhance the autophagy of nucleus pulposus cell, which may be involved in the inhibition of AKT/mTOR signaling.