The Expression Mechanism Of Stromal Derived Factor 1 In Brain Tissue Of Hypoxic-ischemic And The Related Esearch

Objective:Study of stromal cell derived factor-1 (SDF-1) expression in the hypoxic ischemic brain damage tissue and the related mechanism, the dynamic level changes of SDF-1, interleukin -8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) in the serum, and their roles in the hypoxic ischemic brain damage tissue.Methods:Basic research methods:The 90 healthy 7 day old neonatal mice, purchased from the experimental animal center of Shandong University, which were divided into three groups according to the random number method. There are the blank group, control group and SDF-1 intervention group, with 30 mice in each group. According to 24h,3d and 7d three time point,the three groups were randomly divided into three groups. We establish the model of hypoxic-ischemic brain injury in neonatal rats, according to the Rice method and the Wu Wanfang. The neonatal mice of SDF-1 intervention group were given intraperitoneal injection of a certain amount of exogenous SDF-1, the control group were given the same volume of saline, and the blank group did not receive any special treatment. Immunofluorescence and RT-PCR Technology was used to determine the expression levels of SDF-1 in brain tissue of hypoxic ischemic at different time points. We detect the expression level of Ki-67 protein level in the SDF-1 group and the other two groups.Clinical trail methods:82 cases of neonatal hypoxic ischemic encephalopathy were selected as the experimental group, who coming from 2013 July to 2014 November in our hospital neonatal intensive care unit, and 70 cases of normal neonates hospitalized during the same period were randomly selected as the normal control group. We test the serum levels of SDF-1, IL-8, TNF-Alpha in the control group and hypoxic ischemic encephalopathy group before treatment by ELISA method, and to study the dynamic changes in the level of significance. Severe group was divided into group A (acute phase, that is, within 24 hours after birth, and before treatment) and group B (convalescence, born after 7 days, and after treatment), also using enzyme-linked immune method determination of two groups of children with serum SDF-1, IL-8, the expression of TNF alpha level.Results:Results of Basic research:(l)In normal mice brain tissue only very small amounts of SDF-1 protein is expressed, and its expression quantity does not change with time.(2) The expression level of SDF-1 in hypoxic ischemic brain tissue raise obviously, reaches its peak at 3 day, then gradually decline. The level in each time point is higher than that of blank group, and the difference is statistically significant.(3) In the brain tissue of the Blank group, only a small amount of Ki67 protein is expressed.(4) The expression level of Ki67 protein is enhanced obviously. And the change is more obvious in the SDF-1 set, comparing with control group, at each time point, the differences were statistically significant.Results of Clinical trail:(1) The expression level of SDF-1, IL-8 and TNF alpha in the serum of neonatal hypoxic ischemic encephalopathy children were significantly stronger than the control group. And the level of before treatment is higher than after treatment, there is a very significant difference (P< 0.05).(2)The level comparison of SDF-1, IL-8 and TNF alpha between Light, medium and severe HIE patients:In acute stage of HIE, the level of the moderate group is higher than the mild, severe group is also higher than moderate, their differences were statistically significant (P< 0.05).(3)Severe group was divided into group A (acute phase, that is, within 24 hours after birth, and before treatment) and group B (convalescence, born after 7 days, and after treatment), also using enzyme-linked immune method determination of two groups of children with serum SDF-1, IL-8, the expression of TNF alpha level.Conclusions:1 The amount of SDF-1 is increased after ischemia, and the expression tendency have a time window.2 The expression of ki-67 in the serum is increased after ischemia, and the exogenous SDF-1 can promote its expression.3 SDF-1, IL-8 and TNF alpha can reflect the severity of the hypoxic ischemic brain damage, for later the SDF-1 as an indicator of severity of clinical assessment of HIE.4 In this study the endogenous neural cell hyperplasia combined with immunological mechanisms, for SDF- 1 intervention in the treatment of neonatal hypoxic ischemic brain damage to provide theoretical support.