Changes And Significances Of Regulatory T Cell And Cytokines In Neonatal Hypoxic-Ischemic Encephalopathy After Mild Hypothermia Treatment

BackgroundHypoxic-ischemic encephalopathy（HIE）is a kind of neonatal brain damage caused by perinatal asphyxia,which leads to high mortality rate and long-term neurological dysfunction.Mild hypothermia is the only proven effective method for HIE and is generally considered to be the best time window for treatment within 6 hours after birth.Many children with HIE have missed the best time of treatment in clinic.Whether mild hypothermia therapy still has brain protective effect in this kind of children,the clinical understanding is still not uniform.At the same time,the role of immune inflammation in HIE has been paid more and more attention.Therefore,to explore the feasibility of prolonging the time window of mild hypothermia therapy and the significance of immune inflammation in it has become the starting point of this experiment.Objective1.To investigate the therapeutic effect of systemic mild hypothermia on neonatal HIE at 6 h-12 h after birth.2.To elucidate the effect of mild hypothermia treatment on regulatory T cells（Treg）and cytokines in peripheral blood.MethodsA total of 59 newborns with HIE in the First Affiliated Hospital of Xinxiang Medical University from November 2015 to January 2018 were selected as research subjects,children who received systemic mild hypothermia treatment within 6 hours after birth were<6h mild hypothermia group（20 cases）,according to the principle of informed consent,the children were randomly divided into 6h-12h mild hypothermia group（21 cases）and 6h-12h routine group（18 cases）,then according to the conditions the cases were divided into moderate and severe.The control group was treated by classical solutions.Routine treatment includes maintenance of good ventilation,control of convulsions and treatment of brain edema;<6h mild hypothermia group and 6h-12h mild hypothermia group received conventional treatment combined with systemic hypothermia therapy,rectal temperature was controlled at 32℃-34℃for 72 hours and then natural rewarming was performed.All the children were assessed with NBNA scores on the 14th and 28th day after birth.Peripheral venous blood was drawn before and 3 days after treatment in 6h-12h mild hypothermia group and 6h-12h routine group,detection of serum NSE by ELISA;Detection of the percentage of CD4⁺CD25⁺CD127^lowTreg in CD4⁺cells by flow cytometry.Detection of cytokine IL-17A,IL-10,IL-6 and TNF by micro sample multiprotein quantitative technique（CBA）.Results1.Comparison of NBNA scores among the three groups on the 14th and 28th days after birth in children with moderate HIE:the NBNA score of 6h-12h mild hypothermia group was lower than that<6h mild hypothermia group（P>0.05）,then it was higher than that in the 6h-12h routine group during the same period（P<0.05）.Comparison of NBNA scores among the three groups on the 14th and 28th days after birth in children with severe HIE:the NBNA score of 6h-12h mild hypothermia group was lower than that<6h mild hypothermia group（P<0.05）,it was higher than that in the 6h-12h routine group during the same period（P>0.05）.2.The concentrations of NSE in moderate HIE patients with mild 6h-12h hypothermia and 6h-12h routine were lower than those with severe HIE（P<0.05）.Serum NSE concentration reflects the severity of HIE.3.The concentrations of serum NSE in children with moderate 6h-12h hypothermia group and 6h-12h routine group were lower than those before treatment,and the concentration of NSE in 6h-12h mild hypothermia group was lower than that in 6h-12h routine group after treatment（P<0.05）.4.After treatment,the serum NSE levels in severe 6h-12h mild hypothermia group and 6h-12h routine group were not significantly decreased compared with those before treatment（P>0.05）.5.Changes of related cytokines and NSE in moderate 6h-12h mild hypothermia group and 6h-12h routine group before and after treatment.After treatment,the levels of IL-6、IL-10、TNF and IL-17A in the two groups were lower than those before treatment（P<0.05）,the proportion of the two groups of Treg was higher than that before the treatment（P<0.05）;After treatment,the concentrations of IL-6、TNF and IL-17A in6h-12h mild hypothermia group were lower than those in 6h-12h routine group（P<0.05）,the concentration of IL-10 was higher than that of 6h-12h group（P>0.05）,and the ratio of IL-10 was higher than that of 6h-12h group（P<0.05）.6.The Change of cytokines and treg in severe 6h-12h mild hypothermia group and6h-12h routine group before and after treatment.After treatment,the levels of IL-6、IL-10、TNF and IL-17A in the two groups were lower,Treg was higher than those before treatment（P>0.05）;After treatment,the concentrations of IL-6、IL-10、TNF and IL-17A in 6h-12h mild hypothermia group were lower than those in 6h-12h routine group,the proportion of treg was higher than that of 6h-12h routine group（P>0.05）.ConclusionSystemic mild hypothermia was effective in children with moderate HIE at 6h-12h after birth,and starting treatment within 6 hours is better;Mild hypothermia may play a protective role in HIE by increasing the proportion of Treg and inhibiting pro-inflammatory cytokines.