Spermidine, as a natural polyamine with high content in nerve cells, plays roles in regulating synaptic plasticity, promoting autophagy, and alleviating oxidative stress in the nervous system. Spermidine and polyamine metabolism may bring new therapeutic ideas for nervous system injury diseases. This paper reviewed the neuroprotective effects and mechanisms of spermidine in nervous system injury diseases.

Objective:To investigate the protective mechanism of TRPV4 channel inhibitor on blood-brain barrier(BBB)damage after traumatic brain injury(TBI).Methods:The TBI rat model was established.TRPV4 channel inhibitor HC067047 or PKC-δ inhibitor Rottlerin was used to detect changes in BBB permeability,neurological function score,and the expression of microvascular endothelial tight junction proteins ZO-1 and ZO-2 in brain injury areas after TBI.Results:Compared with the Sham group,BBB permeability significantly increased,brain neurological function score significantly decreased,and the expression of ZO-1 and ZO-2 significantly decreased in TBI group(P＜0.05).Compared with the TBI group,after administration of HC067047 or Rottlerin,changes in BBB permeability,brain neurological function score,the expression of ZO-1 and ZO-2 were partially reversed(P＜0.05).Conclusions:TBI-induced BBB injury may be mediated by TRPV4 channel regulating PKC-δ signaling pathway to affect the expression of tight junction proteins ZO-1 and ZO-2.Inhibition of TRPV4 channel function or PKC-δ signal molecule can partially alleviate BBB damage induced by TBI.This study may provide new ideas for the treatment of clinical TBI.