Objective:To investigate the effect of Xuebijing injection against blood-brain barrier(BBB)damage in the mice with anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis,and to elucidate its regulatory effect on the imbalance of helper T cells 17(Th17)/regulatory T cells(Treg).Methods:The active immunization models of anti-NMDAR encephalitis in the mice were established using glutamate receptor N1 subunit(GluN1)356-385 antigen peptide,and the serum anti-NMDAR immunoglobulin G(IgG)antibody levels were detected by enzyme-linked immunosorbent assay(ELISA).The healthy mice without modeling were served as control group,and the mice with successful modeling were randomly divided into model group,low dose of Xuebijing injection(XBJ-L)group,and high dose of Xuebijing injection(XBJ-H)group,with 10 mice in each group.After modeling,the mice in XBJ-L and XBJ-H groups were intraperitoneally injected with 5 and 10 mL·kg-1 Xuebijing injection,respectively.The Longa score was used to assess the neurological impairment of the mice in various groups;evans blue(EB)staining was used to determine the BBB permeability;immunofluorescence staining was used to detect the expressions of zonula occludens 1(ZO-1)and Occludin in cerebral cortex of the mice in various groups;Western blotting method was used to determine the expression levels of ZO-1,Occludin,Claudin-5,and neuron-specific nuclear protein(NeuN)in cerebral cortex of the mice in various groups;ELISA method was used to determine the levels of Th17-and Treg-related cytokines including interleukin(IL)-17,IL-22,and IL-10 in serum of the mice;flow cytometry was used to determine the percentages of Th17 and Treg cells in peripheral blood of the mice in various groups,and the Th17/Treg ratio was calculated.Results:The serum of the mice induced with the GluN1 356-385 antigen peptide was positive for NMDAR IgG antibodies,indicating that the models were successfully established.Compared with control group,the neurological impairment score of the mice in model group was significantly increased(P＜0.05),and the EB level in brain tissue was significantly increased(P＜0.05);the fluorescence staining intensities of ZO-1 and Occludin in the cerebral cortex were decreased,and the expression levels of ZO-1,Occludin,Claudin-5,and NeuN proteins in the cerebral cortex were significantly decreased(P＜0.05);the serum levels of IL-17 and IL-22 were significantly increased(P＜0.05),while the IL-10 level was significantly decreased(P＜0.05);the percentage of Th17 cells in peripheral blood was significantly increased(P＜0.05),while the percentage of Treg cells was significantly decreased(P＜0.05),and the Th17/Treg ratio was significantly increased(P＜0.05).Compared with model group,the neurological impairment scores of the mice in XBJ-L and XBJ-H groups were significantly decreased(P＜0.05),the EB levels in brain tissue were significantly decreased(P＜0.05),the fluorescence staining intensities of ZO-1 and Occludin in cerebral cortex were increased,and the expression levels of ZO-1,Occludin,Claudin-5,and NeuN proteins were significantly increased(P＜0.05);the levels of IL-17 and IL-22 in serum were significantly decreased(P＜0.05),and the level of IL-10 was significantly increased(P＜0.05);the percentages of Th17 cells in peripheral blood were significantly decreased(P＜0.05),the percentages of Treg cells were significantly increased(P＜0.05),and the Th17/Treg ratios were significantly decreased(P＜0.05).Compared with XBJ-L group,the neurological function injury score of the mice in XBJ-H group was significantly decreased(P＜0.05),the EB level in brain tissue was significantly decreased(P＜0.05);the fluorescence staining intensities of ZO-1 and Occludin in the cerebral cortex were increased,and the expression levels of ZO-1,Occludin,Claudin-5,and NeuN proteins were significantly increased(P＜0.05);the serum levels of IL-17 and IL-22 were significantly decreased(P＜0.05),and the level of IL-10 was significantly increased(P＜0.05);the percentage of Th17 cells in peripheral blood was significantly decreased(P＜0.05),the percentage of Treg cells was significantly increased(P＜0.05),and the Th17/Treg ratio was significantly decreased(P＜0.05).Conclusion:Xuebijing injection can improve BBB injury,regulate Th17/Treg balance,and thereby alleviate the neurological functional damage in anti-NMDAR encephalitis.

Objective:To discuss the effect of Xuebijing on brain tissue damage and immune imbalance of helper T lymphocyte 17(Th17)/regulatory T lymphocyte(Treg)in cerebrospinal fluid(CSF)of the N-methyl-D-aspartate(NMDA)receptor encephalitis model mice,and to clarify its therapeutic effect.Methods:Sixty healthy male C57BL/6J mice were randomly divided into control group,model group,low dose of Xuebijing group,and high dose of Xuebijing group,and there were 15 mice in each group.Except for control group,the mice in the other three groups were injected with the antigen combined with immunostimulation to establish the NMDA receptor encephalitis models.The mice in low and high doses of Xuebijing groups were injected intraperitoneally with 5 and 10 mL·kg-1 of Xuebijing injection,respectively.HE staining was used to observe the pathomorphology of brain tissue of the mice in various groups;TUNEL assay was used to detect the apoptotic rates of the neurons in hippocampus CA1 region of brain tissue of the mice in various groups;enzyme-linked immunosorbent assay(ELISA)method was used to detect the levels of interleukin(IL)-6,IL-10,IL-17,and transforming growth factor β(TGF-β)in serum of the mice in various groups;flow cytometry was used to detect the percentages of Th17 and Treg cells in CSF of the mice in various groups;Western blotting method was used to detect the expression levels of retinoic acid-related orphan receptor γt(RORγt),forkhead box protein 3(Foxp3),IL-10,and IL-17 proteins in brain tissue of the mice in various groups;immunohistochemistry method was used to detect the rates of IL-17 and Foxp3 positive cells in brain tissue of the mice in various groups.Results:The HE staining results showed that the hippocampus CA1 region of brain tissue of the mice in control group had a clear structure without obvious lesions;compared with control group,the mice in model group showed partial pyramidal cell shrinkage,elongation of apical dendrites,loss of a few neurons,and sparse tissue in the hippocampus CA1 region of brain tissue;compared with model group,the mice in low and high doses of Xuebijing groups showed that the damage of the cells in the hippocampus CA1 region of brain tissue was decreased,and the morphological recovery,more orderly arrangement,and more significant improvement could be seen in hippocampus CA1 region of the mice in high dose of Xuebijing group.The TUNEL assay results showed that compared with control group,the apoptotic rate of the neurons in hippocampus CA1 region of brain tissue of the mice in model group was significantly increased(P<0.05);compared with model group,the apoptotic rate of the neurons in hippocampus CA1 region of brain tissue of the mice in low and high doses of Xuebijing groups were significantly decreased(P<0.05);compared with low dose of Xuebijing group,the apoptotic rate of the neurons in hippocampus CA1 region of brain tissue of the mice in high dose of Xuebijing group was significantly decreased(P<0.05).The ELISA results showed that compared with control group,the levels of IL-6 and IL-17 in serum of the mice in model group were significantly increased(P<0.05),while the levels of IL-10 and TGF-β were significantly decreased(P<0.05);compared with model group,the levels of IL-6 and IL-17 in serum of the mice in low and high doses of Xuebijing groups were significantly decreased(P<0.05),while the levels of IL-10 and TGF-β were significantly increased(P<0.05);compared with low dose of Xuebijing group,the levels of IL-6 and IL-17 in serum of the mice in high dose of Xuebijing group were significantly decreased(P<0.05),while the levels of IL-10 and TGF-β were significantly increased(P<0.05).The flow cytometry results showed that compared with control group,the percentage of CD4+IL-17A+Th17 cells in CSF of the mice in model group was significantly increased(P<0.05),while the percentage of CD25+Foxp3+Treg cells was significantly decreased(P<0.05);compared with model group,the percentages of CD4+IL-17A+Th17 cells in CSF of the mice in low and high doses of Xuebijing groups were significantly decreased(P<0.05),while the percentage of CD25+Foxp3+Treg cells was significantly increased(P<0.05);compared with low dose of Xuebijing group,the percentage of CD4+IL-17A+Th17 cells in CSF of the mice in high dose of Xuebijing group was significantly decreased(P<0.05),while the percentage of CD25+Foxp3+Treg cells was significantly increased(P<0.05).The Western blotting results showed that compared with control group,the expression levels of RORγt and IL-17 proteins in brain tissue of the mice in model group were significantly increased(P<0.05),while the expression levels of Foxp3 and IL-10 proteins were significantly decreased(P<0.05);compared with model group,the expression levels of RORγt and IL-17 proteins in brain tissue of the mice in low and high doses of Xuebijing groups were significantly decreased(P<0.05),while the expression levels of Foxp3 and IL-10 proteins were significantly increased(P<0.05);compared with low dose of Xuebijing group,the expression levels of RORγt and IL-17 proteins in brain tissue of the mice in high dose of Xuebijing group were significantly decreased(P<0.05),while the expression levels of Foxp3 and IL-10 proteins were significantly increased(P<0.05).The immunohistochemistry results showed that compared with control group,the rate of IL-17 positive cells in brain tissue of the mice in model group was significantly increased(P<0.05),while the rate of Foxp3 positive cells was significantly decreased(P<0.05);compared with model group,the rates of IL-17 positive cells in brain tissue of the mice in low and high doses of Xuebijing groups were significantly decreased(P<0.05),while the rates of Foxp3 positive cells were significantly increased(P<0.05);compared with low dose of Xuebijing group,the rate of IL-17 positive cells in brain tissue of the mice in high dose of Xuebijing group was significantly decreased(P<0.05),while the rate of Foxp3 positive cells was significantly increased(P<0.05).Conclusion:Xuebijing can effectively ameliorate the brain tissue injury,regulate the cytokine levels,and intervene in immune imbalance of Th17/Treg in the mice with anti-NMDA receptor encephalitis.