Effect and mechanism of basic fibroblast growth factor in enhancing neurological recovery after spinal cord injury in rats
10.3760/cma.j.cn501098-20250331-00176
- VernacularTitle:碱性成纤维细胞生长因子促进脊髓损伤大鼠神经功能恢复的作用及其机制
- Author:
Lijuan ZHU
1
;
Ting CAO
;
Shaohua TIAN
;
Xianbao CAO
;
Jun WANG
;
Wenlong ZHANG
Author Information
1. 齐齐哈尔医学院附属第三医院神经内一科，齐齐哈尔 161000
- Publication Type:Journal Article
- Keywords:
Fibroblast growth factors;
Spinal cord injuries;
Protein-serine-threonine kinases;
Autophagy;
Recovery of function
- From:
Chinese Journal of Trauma
2025;41(8):789-797
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the neurorestorative effect of basic fibroblast growth factor (bFGF) on neurological function recovery in rats with spinal cord injury and its potential mechanisms.Methods:Ninety adult SD rats were selected and randomly divided into 6 groups using a random number table: sham-operated group ( n=24), spinal cord injury group ( n=24), bFGF group ( n=24), bFGF autophagy pathway validation group ( n=6), bFGF+rapamycin group ( n=6), and bFGF+MHY1485 group ( n=6). A spinal cord injury model was established by impacting the T 10 spinal cord segment using a self-made Allen′s weight-drop impactor. The sham-operated group underwent a 3 cm midline dorsal incision without spinal cord injury; the bFGF group received immediate intrathecal injection of 100 μl bFGF solution (20 μg/L) after injury; the sham surgery group and spinal cord injury group received an equal volume of saline after injury; the bFGF autophagy pathway validation group received the identical treatment as the bFGF group; the bFGF+rapamycin group received the same treatment as the bFGF group with additional intraperitoneal injection of rapamycin (4 mg·kg -1·d -1); the bFGF+MHY1485 group received the identical bFGF treatment plus intraperitoneal injection of MHY1485 (10 mg·kg -1·d -1). At 28 days after injury, the rats were sacrificed and the spinal cord tissue was collected at 5 mm from the injury epicenter for HE staining and pathological observation. At 7, 14, 21, and 28 days after injury, BBB scoring was used to assess hindlimb motor function; P wave latency and P1-N1 wave amplitude were recorded to evaluate neuroelectrophysiological changes; Western blot analysis was performed to detect the expression levels of phosphorylated mammalian target of rapamycin (p-mTOR)/mammalian target of rapamycin (mTOR) and microtubule-associated protein light chain 3-II (LC3-II) and evaluate changes in mTOR signaling pathway and autophagy activity. At 28 days after injury, behavioral alterations, neuroelectrophysiological changes, and auctophagy-related protein expression levels were assessed in the bFGF autophagy pathyway validation group, bFGF+rapamycin group and bFGF+MHY1485 group. Results:At 28 days after injury, the sham-operated group exhibited regular nuclear morphology, while the spinal cord injury group showed disordered cell structures and the bFGF group displayed relatively normal nuclear morphology. At 7, 14, 21, and 28 days after injury, the BBB scores in both the spinal cord injury group and bFGF group were lower than those in the sham-operated group ( P<0.01), with higher scores in the bFGF group than those in the spinal cord injury group ( P<0.01). At 7, 14, 21, and 28 days after injury, P-wave latency was longer and P1-N1 wave amplitude was lower in both the spinal cord injury group and bFGF group compared to those in the sham-operated group ( P<0.01), with shorter P-wave latency and higher P1-N1 wave amplitude in the bFGF group compared to those in the spinal cord injury group ( P<0.01). Western blot results indicated that at 7, 14, 21, and 28 days after injury, in the spinal cord injury group, p-mTOR/mTOR levels were lower than those in both the sham-operated group and bFGF group ( P<0.01), while LC3-II expression levels were higher ( P<0.01); in the bFGF group, p-mTOR/mTOR levels were higher than those in the spinal cord injury group but lower than those in the sham-operated group ( P<0.01), and LC3-II expression levels were lower than those in the spinal cord injury group but higher than those in the sham-operated group ( P<0.01). At 28 days after injury, the BBB scores were higher in both the bFGF autophagy pathway validation group and bFGF+MHY1485 group than those in the bFGF+rapamycin group ( P<0.01), with higher scores in the bFGF+MHY1485 group than those in the bFGF autophagy pathway validation group ( P<0.01). P-wave latency was shorter in both the bFGF autophagy pathway validation group and bFGF+MHY1485 group than those in the bFGF+rapamycin group ( P<0.01), with shorter P-wave latency in the bFGF+MHY1485 group than that in the bFGF autophagy pathway validation group ( P<0.01). P1-N1 wave amplitude was lower in both the bFGF autophagy pathway validation group and bFGF+MHY1485 group than that in the bFGF+rapamycin group ( P<0.01), with lower P1-N1 wave amplitude in the bFGF+MHY1485 group than that in the bFGF autophagy pathway validation group ( P<0.01). The p-mTOR/mTOR levels were higher in both the bFGF autophagy pathway validation group and bFGF+MHY1485 group than those in the bFGF+rapamycin group ( P<0.01), with higher p-mTOR/mTOR levels in the bFGF+MHY1485 group than those in the bFGF autophagy pathway validation group ( P<0.01). The LC3-II expression levels were higher in both the bFGF autophagy pathway validation group and bFGF+MHY1485 group than those in the bFGF+rapamycin group ( P<0.01), with higher LC3-II expression levels in the bFGF+MHY1485 group than those in the bFGF autophagy pathway validation group ( P<0.01). Conclusion:bFGF can improve the pathological state, motor behavior, and neuroelectrophysiological function in rats with spinal cord injury, for which the mechanism of action may involve downregulating cellular autophagy function by activating the mTOR pathway, thereby inhibiting excessive autophagy to promote neuronal regeneration and repair.
