Regulation Of β-1,3-Galactosyltransferase2 On Transient Ischemic Cerebral Injury In Mice Via Reelin Signaling Pathway

ObjectiveGlycosyltransferases are enzymes that catalyze the formation of a variety of glycoconjugates.Glycoconjugates play vital roles in the nervous system.β-1,3-Galactosyltransferase 2（B3galt2）is one of the major types of glycosyltransferases,which has not been reported in ischemia induced-brain injury.This experiment intends to use the mouse transient cerebral ischemia model as the research object to explore the role and mechanism of B3galt2 in transient cerebral ischemia injury,and to provide a new theoretical basis and therapeutic target for the prevention and treatment of cerebral ischemia injury.MethodsThe B3galt2 knockout heterozygous mice(B3galt2^-/+)were used for breeding,and the genomic DNA PCR genotype identification method was used to determine the genotype of the bred mice,so as to obtain 2-3 months of adult wild type,Heterozygous mice.These mice were passed through middle cerebral artery occlusion（MCAO）for 90 minutes of transient focal cerebral ischemia,and then brain samples were analyzed 24 hours after reperfusion.Western Blotting was used to detect the level of B3galt2 and Reelin in the penumbra around the cerebral ischemic tissue.Nissl staining,TUNEL staining,TTC staining,neurobehavioral scores and other methods were used to detect neuron loss,cerebral infarction volume,cell apoptosis and nerve function damage.ResultsAfter ischemia/reperfusion（I/R）,compared with the control mice,B3galt2^-/+mice have larger cerebral infarction volume and increased neurological damage,and the penumbra around the cerebral ischemic tissue showed severe Neurons were lost,Caspase-3 protein expression increased,and neuronal apoptosis increased,and the expression of Reelin signaling pathway and its downstream protein Dab1 decreased significantly.Overexpression of Reelin recombinant protein can reduce cerebral ischemic damage in B3galt2^-/+mice,and overexpression of B3galt2 can significantly reduce the infarct volume and neuron loss caused by transient cerebral ischemia.ConclusionsOur results suggest B3galt2 deficiency exacerbates ischemic brain damage in acute ischemic stroke in mice,and this was reversed by giving rh-Reelin.B3galt2 might play a beneficial role for neurons survival in the penumbra through modulation of Reelin pathway.