Effects And Mechanism Of Fingolimod On Photochemically Induced Ischemic Model Mice

[Objective]In this study,the most common cerebral ischemic stroke in the clinical work of neurology department were taken as the entry point to explore the influence and mechanism of the new immunosuppressant Finglimod on the the nerve function of the mice model of ischemic stroke induced by photochemical method.It provides animal experimental basis for the further study and application of Finglimod in the treatment of neurological ischemic diseases,and looking for a new strategy for the treatment of neurological ischemic diseases.[Method]In order to study the effect and mechanism of Finglimod on nerve function in photochemically induced cerebral ischemia model mice,the photochemically induced cerebral ischemia model mice were divided into blank control group,simple modeling group and Finglimod group.After24 hours of successful modeling,the Finglimod group received continuous intraperitoneal injection of 0.3mg/kg Finglimod every day,and the simple model group received intraperitoneal injection of equal dose normal saline.Experimental animal behavior were observed for 14 consecutive days in the pure model group and the Finglimod group.The mNSS scale were used to evaluate whether the neurological impairment symptoms of the Finglimod group were improved compared with the simple modeling group.At the time nodes of 1d,7d and 14 d,some mice were sacrificed and brain tissue were taken.Nissl staining was used to observe the survival of nerve cells in the marginal area of cerebral infarction(the corresponding area were taken from the blank control group)in each group.The distribution of M1-type microglia and M2-type microglia in the marginal area of infarction were observed by immunofluorescence staining(the corresponding area were taken from the blank control group).Western Blotting were used to detect the protein expression differences of microglial cell typing indexes in each group.[Result]1.Finglimod can protects the central nervous system.(1)Finglimod can improve the symptoms of neural function defect in cerebral ischemia model mice.The mice model of cerebral ischemia induced by photochemical method was successfully constructed and intraperitoneal injection of Finglimod were given every day for 14 days.By comparing the mNSS scores of mice in different groups,it was found that the mNSS scores of mice in the Finglimod group decreased significantly on the 3rd to 7th day.However,it tends to be stable on 7-14 d and is lower than that in the simple modeling group.The above results indicated that Finglimod could improve the symptoms of nerve function defect in photochemically induced cerebral ischemia model mice.(2)Finglimod can protect neuronsin the marginal areas of cerebral infarction.The mouse model of cerebral ischemia induced by photochemical method were successfully constructed and intraperitoneal injection of Finglimod were given every day.At the time nodes of 1d,7d and 14 d,some mice were sacrificed and brain tissue were taken.The results showed that at the 7th and 14 th days of continuous administration,the number of neurons survived is lower than that of the blank control group,but higher than that of the simple modeling group,with statistical significance.These results suggest that Finglimod can protect neurons in the marginal area of cerebral infarction.2.Finglimod can exert immunomodulatory function and affect microglia typing.The mice model of cerebral ischemia induced by photochemical method were successfully constructed and intraperitoneal injection of Finglimod were given every day.At the time nodes of 1d,7d and 14 d,some mice were sacrificed and brain tissue were taken.(1)The results of immunofluorescence staining(CD16+iba-1)indicated that the expression of CD16 in microglial cells in the Finglimod group were significantly lower than that in the simple modeling group on the 7th day after continuous administration.The results of immunofluorescence staining(CD206+iba-1)indicated that the expression of CD206 in microglial cells in the Finglimod group was higher and statistically significant than that in the simple modeling group at the 7th day of continuous administration.The above results indicated that Finglimodcould reduce the activation of m1-type microglia and promote the generation of M2-type microglia in the marginal area of infarction.(2)Western Blotting experiment results suggested that,On the 7th day of continuous administration,the expression of CD206 and Arg1 protein in microglial cells increased compared with that in the simple modeling group,while the expression of CD16 and iNOS protein decreased compared with that in the simple modeling group and both of them had statistical significance.[Conclusion]Finglimod can alleviate the neuronal necrosis at the edge of infarction in the ischemic model mice induced by photochemistry and improve the symptoms of nerve function defect after cerebral ischemia,The mechanism may be related to the immunomodulatory effect of Finglimod in promoting the transformation of microglia from M1-type to M2-type,thereby reducing inflammation in brain tissue.