Effect Of BFGF On Regeneration And Functional Recovery Of DRG Neurons After Axonal Injury

Peripheral nerve injury is a common disease in the clinic.Because of the limited intrinsic regenerative capacity of adult sensory axons and the growth-inhibiting environment of the dorsal root zone(DREZ)(the interface between the dorsal root and the spinal cord),dorsal root injury always leads to irreversible loss of sensory function.bFGF on spinal cord neurons,in particular,the dorsal root ganglion neurons have a trophic effect.They can activate the ERK1/2,PI3K/AKT,and GSK3B channels to inhibit apoptosis through the transmembrane receptor tyrosine kinase,thereby effectively promoting neuronal survival and axons regeneration.We want to examine the effects of local or systemic treatment with bFGF on nerve regeneration and sensory function recovery after C5-T1 dorsal root injury in rats.The C5-T1 segment of the rat spinal cord was exposed by surgical methods,and an animal model was established by clamping each dorsal root for 5 seconds at the same force.bFGF was administered locally and abdominally for 28 consecutive days for treatment,and local injection of PBS was used as a control.The von fery test and the plantar test were then used to detect sensory function recovery.Western blot was used to detect phosphorylation levels and apoptosis status.Immunofluorescence was used to detect neuronal and axonal regeneration.The results showed that by immunofluorescence staining,we found that injection of bFGF can effectively promote the regeneration of neurons and axons,and the local injection of bFGF is significantly better than abdominal injection.Behavioral results showed that the bFGF-treatmented group was more sensitive to pain stimuli than the PBS control group,and the sensitivity of local administration to stimulation was higher than that of abdominal injection of bFGF.The results of western blot showed that the spinal cord cells after dorsal root injury were rapidly apoptotic and the phosphorylation level was decreased.After bFGF treatment,the apoptosis was inhibited and the phosphorylation level was increased.The effect of local injection of bFGF was more significant.bFGF could effectively promote the regeneration of neurons and the recovery of sensory function after the operation of dorsal root injury.The local injection of bFGF is more effective than abdominal injection.The dorsal root clip surgery simulates a relatively low degree of peripheral nerve injury,and the difference in the mode of administration provides more theoretical basis for the treatment of peripheral nerve injury in the clinic.The positive effect of bFGF on sensory function recovery will be of great significance for the clinical treatment of sensory disorders.