To Investigate The Protective Effect Of Salvianolic Acid B On Mice With Acute Cerebral Ischemia Based On TLR4/NF-κB Signaling Pathway

Part1 The protective effect of Salvianolic Acid B against acute focal cerebral ischemia in miceObjective To discuss the protective effect of Salvianolic Acid B against acute focal cerebral ischemia.Method The acute cerebral ischemic model induced by medial cerebral artery occlusion(MCAO)was reproduced.The modeling mice were given Sal B 11.25,22.5,45mg·kg-1 or Nimhorizon 30μg·kg-1 by tail vein injection after MCAO immediately.The model group and control group were treated with the same volume of physiological saline.After 6h,nerve functional behavior scores were measured,and the brain index,brain water content and the volume of cerebral infarction were determined,and brain tissue pathological morphology were observed.Result After MCAO for 6h,compared with the control group,the nerve functional behavior scores,brain index,brain water content and cerebral infarction volume of Sal B dose groups in mice were significantly improved(P<0.01),brain tissue was pathological damaged,and nucleus pycnosis,dissolved nuclear appeared.Compared with the model group,the nerve functional behavior score,brain index,brain water content and cerebral infarction volume of Sal B dose groups in mice were significantly reduced(P<0.05,P<0.01).According to the results of pathological tissue section,all the Sal B groups could reduce the nerve damage of different area of the cerebral cortex in acute cerebral ischemia mice,could reduce the cerebral infarction volume and improve the pathological injury of brain tissue ischemia.Conclusion Salvianolic Acid B could significantly reduce the nerve function scores,brain water content,cerebral index and the volume of cerebral ischemia,could reduce the nerve damage of different area of the cerebral cortex in acute cerebral ischemia mice,could improve the pathological injury of brain tissue ischemia.It was showed that Sal B has obvious protective effects on acute focal cerebral ischemia in mice.Part2 The influence on the IL-1β and TNF-α of Salvianolic Acid B in acute focal cerebral ischemic brain tissue in mice.Objective To investigate the influence on the IL-1β and TNF-α of Salvianolic Acid B in acute focal cerebral ischemic brain tissue in mice.Method Reproduceing the acute cerebral ischemic model induced by medial cerebral artery occlusion(MCAO),using the method of enzymelinked immunosorbent,according to IL-1β and TNF-α kits for operations,to investigate the influence on the contents of IL-1β and TNF-α of all the Sal B groups in acute focal cerebral ischemic brain tissue in mice.Results Compared with the control group,the content of IL-1β and TNF-α in the model group were dramatically increased.It was indicated that the content of IL-1βand TNF-α in the model group were improved(P<0.01).However,the content of IL-1β and TNF-α of all the Sal B groups in the brain tissue were significantly decreased(P<0.01,P<0.05),compared with the model group.Conclusion Salvianolic Acid B could reduce the content of IL-1β and TNF-α in the brain tissue,which prompted that Salvianolic Acid B could improve the brain inflammation against acute cerebral ischemia by reducing the content of IL-1β and TNF-α inflammatory cytokines in brain tissue.Part3 The impact on the TLR4/NF-κB signaling pathwayof Salvianolic Acid B in acute focal cerebral ischemia in mice.Objective To explore the impact on the TLR4/NF-κB signaling pathway of Salvianolic Acid B in acute focal cerebral ischemia in mice.Method The acute cerebral ischemic model induced by medial cerebral artery occlusion(MCAO)was reproduced,using immunohistochemical method to observe the the expression of TLR4 and NF-κBp50 positive cells in the ischemic cerebral cortex tissue,adopting RT-PCR to test the expression of TLR4 mRNA and NF-κBp65 mRNA in the ischemic cerebral cortex tissue,using the method of western blot detect the protein expression of TLR4、NF-κBp65 in the ischemic cerebral cortex tissue.Result Compared with the control group,the model group could significantly increase the positive cells expression of TLR4 and NF-κBp50 in ischemic brain tissue in MCAO mice.Compared with the model group(P<0.0 1),all the Sal B groups could significantly reduce the positive cells expression of TLR4 and NF-κBp50(P<0.01,P<0.01).The expression of TLR4 and NF-κBp50 were remarkablely increased in the ischemic cerebral cortex tissue in the model group,compared with the control group(P<0.01).The expression of TLR4 and NF-κBp50 were remarkablely the expression of TLR4 and NF-κBp50 were remarkablely decreased in the ischemic cerebral cortex tissue in the Sal B groups in the ischemic cerebral cortex tissue,compared with the model group(P<0.01,P<0.05).Compared with control group,the protein expression of TLR4 and NF-κB in the ischemic cerebral cortex tissue in the model group were significantly risen up(P<0.01).Compared with the model group,all the Sal B groups could decreased the protein expression of TLR4 and NF-κB in the ischemic cerebral cortex tissue(P<0.01,P<0.05).Conclusion Salvianolic Acid B could reduce the related protein expression of TLR4 and NF-κB in the ischemic cerebral tissue,and could decrease the expression of TLR4 mRNA and NF-κBp65 mRNA in the ischemic cerebral tissue.It is revealed that Sal B could reduce the brain inflammation against acute cerebral ischemia by influcing the TLR4/NF-κB signaling pathway.