Ginsenoside Rg1 relieves rat intervertebral disc degeneration and inhibits IL-1-induced nucleus pulposus cell apoptosis and inflammation via NF-B signaling pathway

The study aimed to investigate the effect of ginsenoside Rg1 on intervertebral disc degeneration (IVDD) in rats and IL-1 beta-induced nucleus pulposus (NP) cells, and explore its underlying mechanism. Forty IVDD rat models were divided into the IVDD group, low-dose (L-Rg1) group (intraperitoneal injection of 20 mg/kg/d ginsenoside Rg1), medium-dose (M-Rg1) group (intraperitoneal injection of 40 mg/kg/d ginsenoside Rg1), and high-dose (H-Rg1) group (intraperitoneal injection of 80 mg/kg/d ginsenoside Rg1). The pathological change was observed by HE and safranin O-fast green staining. The expression of IL-1 beta, IL-6, TNF-alpha, MMP3, aggrecan, and collagen II was detected. The expression of NF-kappa B p65 in IVD tissues was detected. Rat NP cells were induced by IL-1 beta to simulate IVDD environment and divided into the control group, IL-1 beta group, and 20, 50, and 100 mu mol/L Rg1 groups. The cell proliferation activity, the apoptosis, and the expression of IL-6, TNF-alpha, MMP3, aggrecan, collagen II, and NF-kappa B pathway-related protein were detected. In IVDD rats, ginsenoside Rg1 improved the pathology of IVD tissues; suppressed the expression of IL-1 beta, IL-6, TNF-alpha, aggrecan, and collagen II; and inhibited the expression of p-p65/p65 and nuclear translocation of p65, to alleviate the IVDD progression. In the IL-1 beta-induced NP cells, ginsenoside Rg1 also improved the cell proliferation and inhibited the apoptosis and the expression of IL-6, TNF-alpha, aggrecan, collagen II, p-p65/p65, and I kappa K in a dose-dependent manner. Ginsenoside Rg1 alleviated IVDD in rats and inhibited apoptosis, inflammatory response, and ECM degradation in IL-1 beta-induced NP cells. And Rg1 may exert its effect via inhibiting the activation of NF-kappa B signaling pathway.