Department of Orthopedic Surgery, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, 430061, Hubei, China.
Department of Orthopedics Ward 1, Hubei Provincial Hospital of Integrated Chinese and Western Medicine, No. 11, Lingjiaohu Road, Jianghan District, Wuhan, 430015, Hubei, China.
Biochem Genet. 2024 Apr;62(2):950-967. doi: 10.1007/s10528-023-10456-z. Epub 2023 Jul 28.
Intervertebral disc (IVD) degeneration (IDD) is a prevalent musculoskeletal disorder. Nucleus pulposus cells (NPCs) play a significant role in the normal functioning of the IVD. Myricetin is an agent that exerts anti-inflammatory and antioxidant effects in various pathological conditions. Here, we investigated the ameliorative effects of myricetin on the IVD degeneration. NPCs were obtained from the IVD of rats, and were treated with myricetin (0, 5, 10, 15, 20 μM) for 24 h before 20 ng/mL IL-1β stimulation. RT-qPCR, western blotting, and ELISA were applied to evaluate the levels of inflammatory factors (iNOS, COX-2, TNF-α, IL-6, PGE2, and Nitrite) and extracellular matrix (ECM)-associated components (MMP13, ADAMTS-5, aggrecan, and collagen II) in NPCs. Activation status of related signaling pathways (NF-κB and Nrf2) was determined using western blotting and immunofluorescence staining. Experimental rat models of IDD were established using a needle puncture method. Myricetin (20 mg/kg) was administrated intraperitoneally, and the degeneration was evaluated using histopathological analysis. Myricetin treatment attenuated the IL-1β-induced production of inflammatory factors in NPCs. Downregulation of aggrecan and collagen II as well as upregulation of MMP-13 and ADAMTS-5 in NPCs caused by IL-1β was reversed by myricetin treatment. Mechanistically, myricetin blocked NF-κB signaling by activation of Nrf2 in IL-1β-stimulated NPCs. Moreover, inhibition of Nrf2 reversed the protective effects of myricetin in NPCs. The in vivo experiments showed that myricetin ameliorated the IDD progression in rats. The present work suggests that Nrf2 is involved in the pathogenesis of IDD and shows the protective effects as well as the underlying mechanism of myricetin on Nrf2 activation in NPCs.
椎间盘（IVD）退变（IDD）是一种常见的肌肉骨骼疾病。核内体细胞（NPC）在 IVD 的正常功能中起着重要作用。杨梅素是一种在各种病理条件下发挥抗炎和抗氧化作用的物质。在这里，我们研究了杨梅素对 IVD 退变的改善作用。从大鼠的 IVD 中获得 NPC，并在用 20ng/mL IL-1β刺激前用杨梅素（0、5、10、15、20μM）处理 24h。应用 RT-qPCR、western blot 和 ELISA 评估 NPC 中炎症因子（iNOS、COX-2、TNF-α、IL-6、PGE2 和亚硝酸盐）和细胞外基质（ECM）相关成分（MMP13、ADAMTS-5、聚集蛋白聚糖和胶原 II）的水平。使用 western blot 和免疫荧光染色测定相关信号通路（NF-κB 和 Nrf2）的激活状态。使用针刺法建立 IDD 实验大鼠模型。腹腔内给予杨梅素（20mg/kg），并通过组织病理学分析评估退变。杨梅素处理可减轻 IL-1β诱导的 NPC 中炎症因子的产生。IL-1β诱导的 NPC 中聚集蛋白聚糖和胶原 II 的下调以及 MMP-13 和 ADAMTS-5 的上调被杨梅素处理逆转。机制上，杨梅素通过激活 Nrf2 阻断了 IL-1β刺激的 NPC 中的 NF-κB 信号。此外，抑制 Nrf2 逆转了杨梅素在 NPC 中的保护作用。体内实验表明，杨梅素可改善大鼠的 IDD 进展。本研究表明，Nrf2 参与了 IDD 的发病机制，并显示了杨梅素对 NPC 中 Nrf2 激活的保护作用及其潜在机制。
