背景:化疗诱导的周围神经病变(CIPN)是一种常见的并发症,影响越来越多的癌症幸存者。然而,目前CIPN的治疗方案有限.紫杉醇(PTX)是一种广泛使用的化疗药物,可诱导癌细胞衰老。虽然以前的研究表明,Sonichedgehog(Shh)可以抵消衰老过程中的细胞功能障碍,其在CIPN中的作用尚不清楚。
目的:在此,这项研究的目的是研究Shh激活是否可以抑制神经元/神经胶质衰老并减轻CIPN。
方法:我们在PTX存在下用两种选择性Shh激活剂(purmorphamine[PUR]和平滑激动剂[SAG])处理ND7/23神经元细胞和RSC96雪旺氏细胞。此外,我们利用PTX注射诱导的aCIPN小鼠模型。为了评估细胞衰老,我们进行了衰老相关的β-半乳糖苷酶(SA-β-gal)测定,测得的活性氧(ROS)水平,并检测了P16、P21和γH2AX的表达。要了解潜在的机制,我们进行了泛素检测,LC-MS/MS,H&E染色,并通过蛋白质印迹和免疫荧光染色评估蛋白质表达。
结果:体外,我们观察到Shh激活可显着缓解衰老相关的多种功能下降,包括SA-β-gal活性,P16和P21的表达,细胞活力,PTX暴露后DRG感觉神经元和雪旺细胞中ROS的积累。此外,我们的体内实验表明,Shh激活显着减少轴突变性,脱髓鞘,改善神经传导.机械上,我们发现PTX降低了SP1的蛋白水平,该蛋白在赖氨酸694(K694)被E3连接酶TRIM25泛素化,导致CXCL13表达增加,我们发现Shh激活通过TRIM25-SP1-CXCL13轴抑制PTX诱导的神经元/神经胶质衰老和CIPN。
结论:这些发现为PTX诱导的衰老在DRG感觉神经元和雪旺细胞中的作用提供了证据,提示Shh可能是CIPN的潜在治疗靶点。
BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common complication that affects an increasing number of cancer survivors. However, the current treatment options for CIPN are limited. Paclitaxel (PTX) is a widely used chemotherapeutic drug that induces senescence in cancer cells. While previous studies have demonstrated that Sonic hedgehog (Shh) can counteract cellular dysfunction during aging, its role in CIPN remains unknown.
OBJECTIVE: Herein, the aim of this study was to investigate whether Shh activation could inhibits neuronal/glial senescence and alleviates CIPN.
METHODS: We treated ND7/23 neuronal cells and RSC96 Schwann cells with two selective Shh activators (purmorphamine [PUR] and smoothened agonist [SAG]) in the presence of PTX. Additionally, we utilized a CIPN mouse model induced by PTX injection. To assess cellular senescence, we performed a senescence-associated β-galactosidase (SA-β-gal) assay, measured reactive oxygen species (ROS) levels, and examined the expression of P16, P21, and γH2AX. To understand the underlying mechanisms, we conducted ubiquitin assays, LC-MS/MS, H&E staining, and assessed protein expression through Western blotting and immunofluorescence staining.
RESULTS: In vitro, we observed that Shh activation significantly alleviated the senescence-related decline in multiple functions included SA-β-gal activity, expression of P16 and P21, cell viability, and ROS accumulation in DRG sensory neurons and Schwann cells after PTX exposure. Furthermore, our in vivo experiments demonstrated that Shh activation significantly reduced axonal degeneration, demyelination, and improved nerve conduction. Mechanistically, we discovered that PTX reduced the protein level of SP1, which was ubiquitinated by the E3 ligase TRIM25 at the lysine 694 (K694), leading to increased CXCL13 expression, and we found that Shh activation inhibited PTX-induced neuronal/glial senescence and CIPN through the TRIM25-SP1-CXCL13 axis.
CONCLUSIONS: These findings provide evidence for the role of PTX-induced senescence in DRG sensory neurons and Schwann cells, suggesting that Shh could be a potential therapeutic target for CIPN.