Effects Of Gastrodin On Inflammation Of Astrocytes After HIBD In Neonatal Rats

Objective（s）:In order to explore the effect of gastrodin（GAS）on expression of matrix metalloproteinase-9（MMP-9）,monocyte chemoattractant factor-1（MCP1）,vascular endothelial growth factor A（VEGFA）in astrocytes after hypoxic-ischemic brain damage（HIBD）,we copied neonatal rat hypoxic-ischemic model in vivo and TNC1 astrocyte model induced by oxygen glucose deprivation（OGD）in vitro,which to explore the mechanism of gastrodin inhibiting inflammation after HIBD and provide laboratory basis for clinical treatment of neonatal HIBD.Methods:In vivo experiment,3-day-old newborn Sprague Dawley（SD）rats were selected and randomly divided into sham（Sham）,HIBD,HIBD+gastrodin intervention（HIBD+G）groups.The neonatal HIBD rat model was established by ligation of the left common carotid artery using the rice-Vannucci method followed by hypoxia（8%O₂+92%N₂）for 2h in a hypoxia chamber.The HIBD+G group was administered intraperitoneally for three times（100 mg/kg）,1 h before ligation,immediately after hypoxia,and 12 h after hypoxia.Immunofluorescence double labelling and Western blot were used to detect the expression of MMP9,MCP1,VEGFA in the penumbra region of the left injured cortex at 1d,3d,7d after HIBD.In vitro experiment,TNC1 astrocytes were randomly divided into control（Control）,glucose oxygen deprivation（OGD）,and OGD+gastrodin（OGD+G）groups.GAS（0.34 m M）was pretreated for 1 h in OGD+G group,then the OGD+G group and OGD group were subjected to hypoxia for 4 h.The expression of MMP9,MCP1,VEGFA in astrocytes were detected by immunofluorescence double labelling and Western blot.Results:Large numbers of activated astrocytes were found in the penumbra of the cortex after HIBD in neonatal rats,with hypertrophic cell body and more processes.In vivo,immunofluorescence double labelling and Western blot results showed that MMP9,MCP1,VEGFA expressions were significantly increased in the HIBD group compared with the Sham group（P<0.05）,and GAS could reduce the expression of MMP9,MCP1,VEGFA（P<0.05）at 1d,3d and 7d after HIBD;In vitro,immunofluorescence double labelling and Western blot results also showed that MMP9,MCP1,VEGFA expressions were significantly increased in OGD group compared with Control group（P<0.05）,and GAS intervention significantly decreased the expression of MMP9,MCP1,VEGFA in astrocytes after OGD（P<0.05）.Conclusion（s）:Large numbers of activated astrocytes were found in the penumbra of the cortex after HIBD in neonatal rats.MMP9,MCP1,and VEGFA expression in reactive astrocytes was increased.The expressions of MMP9,MCP1and VEGFA in TNC1 astrocytes induced by OGD in vitro were also increased.It indicating that these factors were involved in the pathological process of HIBD and astrocyte mediated neuroinflammatory response.GAS significantly inhibited the expression of MMP9,MCP1,VEGFA in astrocytes and alleviated the neuroinflammation mediated by it,thereby exerting neuroprotective effects on HIBD in neonatal rats.