FOXG1 interaction with SATB2 promotes autophagy to alleviate neuroinflammation and mechanical abnormal pain in rats with lumbar disc herniation

Most patients with lumbar disc herniation can be relieved or cured by surgical or non-surgical treatment; however, postoperative persistent radiculopathy is common. This study demonstrates the regulation of autophagy by the FOXG1/SATB2 axis in lumbar disc herniation (LDH). Rat dorsal root neurons were induced with TNF-α <i>in vitro</i>. Sprague Dawley (SD) rats were used to construct the LDH rat model, which was treated with <i>L. paracasei S16</i> or oe-FOXG1. Paw withdrawal threshold or latency assay (PWT/L) was performed. Peripheral blood samples were collected and analysed using ELISA and miRNAseq. RT-qPCR was used to analyse the expression of FOXG1, LC3B, Beclin1, p62, and SATB2. TUNEL staining and flow cytometry were used to analyse apoptosis. The expression of Cyclin D1, PCNA, Ki67, FOXG1, SATB2, and autophagy proteins was measured using western blotting. TNF-α induced low expression of FOXG1 and SATB2 in dorsal root ganglion (DRG) neurons of rats. TNF-α induced an increase in p62 protein and a decrease in LC3II/I and Beclin-1 proteins in neurons, which were blocked by oe-FOXG1. oe-FOXG1 suppressed inflammation and apoptosis in TNF-α-induced DRG neurons and LDH rats and promoted the expression of Cyclin D1, PCNA, and Ki67. Many miRNAs were increased in the peripheral blood of LDH rats, but decreased after <i>L. paracasei S16</i> intervention. <i>L. paracasei S16</i> affects miR-31a-5p and SATB2 expression. Dual luciferase reporter gene assay confirmed that miR-31a-5p bound to SATB2. Co-IP analysis confirmed the interaction between FOXG1 and SATB2. Silencing of SATB2 inhibited the beneficial effects of oe-FOXG1 in TNF-α-induced dorsal root ganglion neurons. Animal experiments further demonstrated that oe-FOXG1 improved LDH disease characteristics by downregulating PWT, PWL, inflammation, and apoptosis levels and upregulating SATB2-autophagy levels. MiR-31a-5p/SATB2 is involved in the treatment of <i>L. paracasei S16</i> in LDH rats. Overexpression of FOXG1 promotes autophagy through SATB2 to improve LDH levels This provides a new approach for the treatment of LDH.

大多数腰椎间盘突出症患者可通过手术或非手术治疗缓解或治愈；然而，术后持续性神经根病（radiculopathy）较为常见。本研究揭示了FOXG1/SATB2轴在腰椎间盘突出症（LDH）中对自噬（autophagy）的调控作用。体外（*in vitro*）使用TNF-α诱导大鼠背根神经元。采用Sprague Dawley（SD）大鼠构建LDH大鼠模型，并使用*L. paracasei S16*或oe-FOXG1进行处理。进行爪退缩阈值或潜伏期测定（PWT/L）。采集外周血样本，采用ELISA和miRNAseq进行分析。采用RT-qPCR分析FOXG1、LC3B、Beclin1、p62和SATB2的表达水平。采用TUNEL染色和流式细胞术分析细胞凋亡（apoptosis）。采用蛋白质印迹法（western blotting）检测Cyclin D1、PCNA、Ki67、FOXG1、SATB2及自噬相关蛋白的表达水平。TNF-α诱导大鼠背根神经节（DRG）神经元中FOXG1和SATB2低表达。TNF-α诱导神经元中p62蛋白增加，LC3II/I和Beclin-1蛋白减少，而oe-FOXG1可阻断这一效应。oe-FOXG1可抑制TNF-α诱导的DRG神经元及LDH大鼠的炎症反应和细胞凋亡，并促进Cyclin D1、PCNA和Ki67的表达。LDH大鼠外周血中多种miRNA表达升高，但经*L. paracasei S16*干预后降低。*L. paracasei S16*可影响miR-31a-5p和SATB2的表达。双荧光素酶报告基因实验证实miR-31a-5p与SATB2存在结合作用。Co-IP分析证实FOXG1与SATB2之间存在相互作用。沉默SATB2可抑制oe-FOXG1对TNF-α诱导的背根神经节神经元的有益作用。动物实验进一步表明，oe-FOXG1通过下调PWT、PWL、炎症反应及细胞凋亡水平，上调SATB2-自噬水平，改善LDH的疾病特征。MiR-31a-5p/SATB2参与了*L. paracasei S16*对LDH大鼠的治疗作用。FOXG1过表达通过SATB2促进自噬，从而改善LDH病情，为LDH的治疗提供了新策略。