Netrin-1 在骨癌痛大鼠模型中通过激活 DCC 信号促进伤害性神经元出芽的作用。

Netrin-1 Role in Nociceptive Neuron Sprouting through Activation of DCC Signaling in a Rat Model of Bone Cancer Pain.

机构信息

Department of Anesthesiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, School of Medicine, 200030 Shanghai, China.

School of Medicine, Shanghai University, 200444 Shanghai, China.

出版信息

J Integr Neurosci. 2024 Feb 27;23(3):47. doi: 10.31083/j.jin2303047.

DOI:10.31083/j.jin2303047

PMID:38538215

Abstract

BACKGROUND

Bone cancer pain (BCP) is a common primary or metastatic bone cancer complication. Netrin-1 plays an essential role in neurite elongation and pain sensitization. This study aimed to determine the role of netrin-1 from the metastatic bone microenvironment in BCP development and identify the associated signaling pathway for the strategy of BCP management.

METHODS

The rat BCP model was established by intratibial implantation of Walker 256 cells. Von Frey filaments measured the mechanical pain threshold. Movement-induced pain was assessed using limb use scores. Expressions of associated molecules in the affected tibias or dorsal root ganglia (DRG) were measured by immunofluorescence, immunohistochemistry, real-time quantitative polymerase chain reaction, or western blotting. Transduction of deleted in colorectal cancer (DCC) signaling was inhibited by intrathecal injection of DCC-siRNA.

RESULTS

In BCP rats, the presence of calcitonin gene-related peptide (CGRP)-positive nerve fibers increased in the metastatic bone lesions. The metastatic site showed enrichment of well-differentiated osteoclasts and expressions of netrin-1 and its attractive receptor DCC. Upregulation of DCC and increased phosphorylation levels of focal adhesion kinase (FAK) and Rac family small GTPase 1/Cell division cycle 42 (Rac1/Cdc42) were found in the DRG. Intrathecal administration of DCC-siRNA led to a significant reduction in FAK and Rac1/Cdc42 phosphorylation levels in the DRG, decreased nociceptive nerve innervation, and improved pain behaviors.

CONCLUSIONS

Netrin-1 may contribute to the activation of the BCP by inducing nociceptive nerve innervation and improving pain behaviors.

摘要

背景

骨癌痛（BCP）是一种常见的原发性或转移性骨癌并发症。轴突导向因子 netrin-1 在轴突伸长和疼痛敏化中发挥重要作用。本研究旨在确定转移性骨微环境中的 netrin-1 在 BCP 发展中的作用，并确定用于 BCP 管理的相关信号通路。

方法

通过胫骨内植入 Walker 256 细胞建立大鼠 BCP 模型。通过 Von Frey 纤维测量机械疼痛阈值。通过肢体使用评分评估运动引起的疼痛。通过免疫荧光、免疫组织化学、实时定量聚合酶链反应或蛋白质印迹测量受影响胫骨或背根神经节（DRG）中相关分子的表达。通过鞘内注射 DCC-siRNA 抑制Deleted in colorectal cancer（DCC）信号转导。

结果

在 BCP 大鼠中，降钙素基因相关肽（CGRP）阳性神经纤维在转移性骨病变中增加。转移部位表现出分化良好的破骨细胞的富集和 netrin-1 及其吸引受体 DCC 的表达。在 DRG 中发现 DCC 上调和粘着斑激酶（FAK）和 Rac 家族小 GTP 酶 1/细胞分裂周期蛋白 42（Rac1/Cdc42）的磷酸化水平增加。鞘内给予 DCC-siRNA 可导致 DRG 中 FAK 和 Rac1/Cdc42 磷酸化水平显著降低，减少伤害性神经支配，并改善疼痛行为。