Inhibition of toll-like receptor 4 protects against inflammation-induced mechanobiological alterations to intervertebral disc cells.
Inhibition of toll-like receptor 4 protects against inflammation-induced mechanobiological alterations to intervertebral disc cells.
复制标题
抑制toll样受体4可保护椎间盘细胞免受炎症诱导的机械生物学改变。
DOI：
10.22203/ecm.v041a37
复制
发表时间：
2021-05-20
影响因子：
3.1
通讯作者：
Chahine NO
中科院分区：
文献类型：
--
作者：
Jacobsen TD;Hernandez PA;Chahine NO
椎间盘（IVD）退变与疾病病因和基质降解相关的炎性细胞因子水平升高相关。Toll样受体-4（TLR 4）已被证明参与髓核（NP）的炎症反应，其水平在椎间盘退变中上调。NP细胞中TLR 4的激活导致细胞生物物理性质的显著、持续的变化，包括水力渗透性和水活性含量，以及肌动蛋白细胞骨架的改变。该研究假设炎症诱导的细胞生物力学特性和NP细胞肌动蛋白细胞骨架的变化可以通过抑制TLR 4信号传导来预防。用脂多糖（LPS）（研究最好的TLR 4激动剂）处理来自牛椎间盘的分离的NP细胞，用或不用TLR 4抑制剂TAK-242处理。测量细胞对逐步渗透负荷的体积调节反应，并通过延时显微镜捕获瞬时体积反应。利用混合物理论框架分析了体积响应，以研究水力渗透率和细胞内活性水含量。LPS处理后，水力渗透性和细胞半径显著增加，这些变化在TAK-242处理的细胞中被阻断。TAK-242治疗也减轻了LPS诱导的皮质肌动蛋白重塑和IL-6上调。这些发现表明TLR 4信号传导参与NP细胞生物物理调节，并且可能是减轻在IVD炎症和变性中观察到的改变的细胞反应的重要靶点。
Intervertebral disc (IVD) degeneration is associated with elevated levels of inflammatory cytokines implicated in disease aetiology and matrix degradation. Toll-like receptor-4 (TLR4) has been shown to participate in the inflammatory responses of the nucleus pulposus (NP) and its levels are upregulated in disc degeneration. Activation of TLR4 in NP cells leads to significant, persistent changes in cell biophysical properties, including hydraulic permeability and osmotically active water content, as well as alterations to the actin cytoskeleton. The study hypothesis was that inflammation-induced changes to cellular biomechanical properties and actin cytoskeleton of NP cells could be prevented by inhibiting TLR4 signalling. Isolated NP cells from bovine discs were treated with lipopolysaccharide (LPS), the best studied TLR4 agonist, with or without treatment with the TLR4 inhibitor TAK-242. Cellular volume regulation responses to step osmotic loading were measured and the transient volume-response was captured by time-lapse microscopy. Volume-responses were analysed using mixture theory framework to investigate hydraulic permeability and osmotically active intracellular water content. Hydraulic permeability and cell radius were significantly increased with LPS treatment and these changes were blocked in cells treated with TAK-242. LPS-induced remodelling of cortical actin and IL-6 upregulation were also mitigated by TAK-242 treatment. These findings indicated that TLR4 signalling participated in NP cell biophysical regulation and may be an important target for mitigating altered cell responses observed in IVD inflammation and degeneration.