The Protective Effect And Mechanism Of Lutein On Hypoxic-ischemic Brain Damage In Neonatal Rats

PurposesTo investigate the protective effects of lutein on hypoxic-ischemic brain damage in neonatal rats in vivo and oxygen-glucose deprivation injury in primary neuronal cells in vitro and the related mechanisms.Methods1.The SD rats of 4th days old were randomly divided into Sham group,HIBD group and Lutein group,the model of hypoxic-ischemic brain damage(HIBD)in neonatal rats used in this study was constructed when the rats was 7th days old.Then the degree of cerebral edema in each group was detected by dry-wet weight method,The infarct volume of brain tissue was detected by TTC staining.The The locomotor activity testing was used to test the autonomic activity of neonatal rats in each group.Morris water maze testing was used to investigate the spatial learning and memory ability of neonatal rats in each group.2.The apoptosis of neurons in the brain tissue of each group neonatal rats was detected by HE staining and TUNEL staining.The expression levels of related proteins in brain tissue of each group were detected by immunohistochemistry and Western blotting.To explore the molecular mechanism of lutein plays a protective role.3.The primary neuronal cells were isolated and cultured from the rat brain within 24 h,and randomly divided into Control group,OGD group and Lutein group.And then cultured to the 7th day,the oxygen glucose deprivation(OGD)injury model in the neuronal cells was constructed.MTT assay was used to detect the survival rate of neurons in each group.LDH release was used to detect the release of LDH between neurons in each group.4.The apoptosis of neuronal cells in each group was detected by Hoechst 33258 staining assay.The expression of NeuN protein in the neurons of each group was detected by immunofluorescence.Results1.Lutein could significantly reduce the degree of brain tissue edema induced by HIBD in neonatal rats;Lutein could significantly reduce the infarct volume induced by HIBD of brain tissue in neonatal rats;Lutein could significantly improve the locomotor activity and learning and memory ability in neonatal rats.2.Lutein could significantly reduce neuronal apoptosis in brain tissue of neonatal rats.Lutein could significantly increase the expression of NeuN protein in cerebral cortex and hippocampus in neonatal rats,up-regulated the expression of p-PI3 K and pAkt,down-regulated the expression of p-GSK-3?,up-regulated the anti-apoptotic protein Bcl-2 and Bcl-xl as well as down-regulated the expression of pro-apoptotic proteins Bax and Bad.3.Lutein could significantly increase the survival rate of neurons in vitro and reduce the release of LDH in neuronal cells induced by OGD.4.Lutein could significantly attenuate OGD-induced neuronal nuclear damage and increase the expression of NeuN protein in neuronal cells.ConclusionLutein has significant protective effects on HIBD brain injury of neonatal rat and OGD injury in neonatal rats primary neuronal cells,and its mechanism may be related to the activation of PI3K/AKT/GSK-3? signaling pathway and the inhibition of mitochondrial apoptosis pathway.