Effect of vitexin on motor function and inflammation in rats with spinal cord injury
Objective:To investigate the effect of vitexin(VT)on spinal cord injury(SCI)rats and lipopolysac-charide(LPS)-induced BV2 microglia.Methods:In vivo experiments:SD rats were divided into sham-operated group(sham group),model SCI group(model group)and VT low-dose,VT medium-dose and VT high-dose groups.Basso-Beattie-Bresnahan(BBB)score was used to evaluate the motor function of rats;reverse transcrip-tion-quantitative PCR(RT-qPCR)and enzyme-linked immunoassay(ELISA)were used to detect the gene and protein expression of inflammatory factors in rats;hematoxylin-eosin(HE)staining was used to observe the spi-nal cord tissue structure.In vitro experiments:BV2 microglia were divided into normal control group(control group),LPS group,VT low-dose,medium-dose and high-dose groups and VT high-dose alone administration group;LPS-induced BV2 microglia activation was used to construct in vitro neuroinflammation model;cell counting kit-8(CCK-8)method was used to screen the range of safe concentration of VT;RT-qPCR and western blotting were used to detect the levels of cellular inflammatory gene and protein expression.Results:In vivo ex-periments:compared with the SCI group,the BBB scores of the VT medium-and high-dose groups were signifi-cantly higher,and the score of the VT medium-dose group was significantly higher than that of the high-dose group on the 7th day of the injury(both P<0.05);the expression of TNF-α mRNA in the VT medium-dose group was lower compared with that of the SCI group,and the expression of IL-10 mRNA in the VT medium-and high-dose groups was significantly higher compared with that in the SCI group(both P<0.05);the protein levels of TNF-α in the VT low-dose group,VT medium-dose group and VT high-dose group were significantly decreased(all P<0.05),and the protein levels of IL-10 in the VT dose groups were significantly increased(all P<0.05);HE results showed that the spinal cord in the sham group was structurally intact,with more neurons and a more regular arrangement;spinal cord tissue in the SCI group was infiltrated with inflammatory cells,showed more cavities,and neurons were reduced and atrophied with irregular arrangement;compared with the SCI group,the damage in the VT treatment group was smaller,and the reduction of inflammatory infiltration was more obvious.In vitro experiments:compared with the LPS group,TNF-α mRNA expression was significantly reduced in each dose group of VT(all P<0.05),and reduced in a dose-dependent manner;TNF-α protein expression was reduced in each group of VT(all P<0.001).Conclusion:VT inhibits the inflammation of rats,reduces the histopathologi-cal damage of the spinal cord,and improves the local microenvironment of the spinal cord after injury,thereby protecting the damaged spinal cord neurons,and promoting the recovery of motor function.