The Effect Of Triple Reuptake Inhibitor Toludesvenlafaxine On Neurological Function And Depression After Cerebral Ischemia

Background:Stroke is the leading killer of physical disability and death of adults in China,continues to rise each year.Cell death in brain after stroke is an important cause of neurological dysfunction in patients.Despite the abnormal neuronal function in the ischemic area,cells in the ischemic hemispheric area are still alive.Toludesvenlafaxine is a new chemical entity that is particularly critical for improving the prognosis of stroke.As a selective serotonin（5-HT）,norepinephrine（NE）and dopamine（DA）reuptake inhibitor,Toludesvenlafaxine increases the levels of 5-HT,NE and DA in the synaptic gap.It is not clear whether Toludesvenlafaxine is beneficial in ischemic stroke because of the controversial protective effect of DA on cerebral ischemia.Also post-stroke depression（PSD）as a common disorder after stroke,it is not clear whether Toludesvenlafaxine is effective in PSD.Objective:To clarify the effect of Toludesvenlafaxine on neurological impairment due to cerebral ischemia and its mechanism study;to clarify the effect of Toludesvenlafaxine on PSD and its mechanism study.Methods:Experiment 1:The effect of Toludesvenlafaxine on neurological impairment due to cerebral ischemia（1）Male SD rats were randomly divided into Sham group,Model group,Nimodipine group,Toludesvenlafaxine 4.0 mg/kg group,Toludesvenlafaxine 8.0 mg/kg group and Toludesvenlafaxine 16.0 mg/kg group.Cerebral ischemia models were prepared using the middle cerebral artery obstruction（MCAO）method.Nimodipine and different doses of Toludesvenlafaxine were administered by gavage 30 minutes before modeling.Equal amounts of lysate were given to the Sham and Model groups at the same time.The effect of Toludesvenlafaxine on the neurological function of rats with cerebral ischemia was examined by Garcia scores and foot fault test 24 hours after MCAO.The changes of cerebral infarct size were also observed by TTC staining.（2）We observed neuronal apoptosis by TUNEL staining in the cerebral cortex of the peri-infarct area,and detected the expression of Bcl-2,Bax,Caspase-3 and BDNF by Western Blot.For the study of signaling pathways,we observed the expression of p-CREB in the peri-infarct region by both immunofluorescence detection and Western Blot detection.And we further verified the role of this pathway by observing the effect of CREB pathway blocker 666-15 on cerebral ischemic rats.Experiment 2:The effect of Toludesvenlafaxine on Co Cl₂induced cytotoxicity in SH-SY5YWe examined the cellular activity of SH-SY5Y when different doses of Co Cl₂were given by CCK-8 and used it to explore the optimal modeling conditions.The cells were divided into control group,Co Cl₂group and Toludesvenlafaxine group.The cells were incubated with different concentrations of Toludesvenlafaxine for 12 h and then re-incubated in the incubator with Co Cl₂for 12 h.The cell activity was measured by CCK-8,and the changes of cell morphology were observed by light microscopy and apoptosis was observed by TUNEL staining.Experiment 3:The effect of Toludesvenlafaxine on post-stroke depression and its mechanismWe randomly divided male SD rats into Sham group,Model group,Toludesvenlafaxine 4.0 mg/kg group,Toludesvenlafaxine 8.0 mg/kg group and Toludesvenlafaxine 16.0 mg/kg group.PSD model was prepared by the MCAO/R combined with chronic unpredictable mild stimulation.Successful models were screened by sugar-water preference assay on day 17 after modeling and administered in randomized groups.The rats were gavaged with the appropriate drug or lysate once a day for 7 d.The neurological function of the rats was observed by Garcia scores,and the depressive symptoms of the rats were observed by sugar water preference test and forced swimming test.Results:Experiment 1:Compared with the Sham group,the Garcia scores were decreased,the misstep rate was increased,and the area of cerebral infarction and the number of neuronal apoptosis were increased in cerebral ischemic rats.The expression of apoptosis-related proteins was decreased,while the expression of BDNF and p-CREB was increased by Western Blot.The expression of p-CREB in the nucleus was also increased by immunofluorescence assay.Experiment 2:Co Cl₂resulted in decreased cell activity,and 200μM was the optimal modeling concentration.And Co Cl₂altered cell morphology and significant damage,and an increase in the number of apoptotic cells compared to the CN group.With Toludesvenlafaxine,cell activity was increased,cell morphology was only slightly altered,and apoptosis was reduced.Experiment 3:Rats after PSD had a reduced rate of sugar-water bias,prolonged immobility in the forced swim experiment,and reduced Garcia scores compared to Sham group.With Toludesvenlafaxine,sugar-water partiality was increased,immobility time was reduced,Garcia scores were increased,and the levels of inflammatory factors,including TNF-α,IL-1βand IL-6,were reduced,and BDNF expression in the hippocampus was increased.Conclusion:Toludesvenlafaxine significantly improved neurological impairment,reduced cerebral infarct size and neuronal apoptosis.Toludesvenlafaxine improved depression-like behavior in PSD rats,which was associated with the promotion of BDNF expression in the hippocampus and inhibition of inflammation.Innovation:This study was the first to show that the selective 5-HT,NE and DA reuptake inhibitor Toludesvenlafaxine improved neurological impairment and reduced neuronal apoptosis in rats with cerebral ischemia.Toludesvenlafaxine improved depression-like behavior in PSD rats.