腰突颗粒通过调控 miR-221 表达干预髓核细胞的增殖与凋亡.

BACKGROUND: MicroRNA is involved in intervertebral disc degeneration, and Yaotu Granule can significantly delay the progress of intervertebral disc degeneration. OBJECTIVE: To investigate the effect of Yaotu Granule in the proliferation and apoptosis of nucleus pulposus cells by regulating the expression of microRNA-221 (miR-221). METHODS: MiR-221 mimics and inhibitors were transfected into rat nucleus pulposus cells to establish miR-221 overexpression and inhibition models. Tumor necrosis factor-α was used to induce nucleus pulposus cell degeneration model. The degenerated nucleus pulposus cells were treated with 100 and 200 mg/L Yaotu Granule freeze-dried powder (low and high dose groups). In the miR-221 mimics + Yaotu Granule group, miR-221 mimic and 200 mg/L Yaotu Granule freeze-dried powder were added. Cell counting kit-8 and TUNEL assay were used to detect the cell proliferation and apoptosis, RT-qPCR was used to detect mRNA expression of miR-221, and western blot was used to detect the expression of Bax and Bcl-2. RESULTS AND CONCLUSION: MiR-221 mimics reduced cell prolifecation at 24, 48, 72 hours (P < 0.05) and promoted cell apoptosis at 48 hours (P < 0.05); miR-221 inhibitors had the opposite results (P < 0.05). Compared with the normal group, tumor necrosis factor-α inhibited cell proliferation, increased cell apoptosis, and upregulated miR-221 expression (all P < 0.05). Compared with the model group, low- and high-dose Yaotu Granules increased cell proliferation, reduced cell apoptosis, and downregulated miR-221 expression (all P < 0.05). Compared with the mimics group, cell proliferation improved, apoptosis rate decreased, the protein expression of Bax reduced, and the Bcl-2 protein expression up-regulated in the miR-221 mimics + Yaotu Granule group (all P < 0.05). To conclude, miR-221 has an effect on the proliferation and apoptosis of nucleus pulposus cells, and Yaotu Granule can delay the progression of intervertebral disc degeneration by downregulating the expression of miR-221. [ABSTRACT FROM AUTHOR]