Effects of glucocorticoids on brain protection and cerebrospinal fluid immunoglobulin levels in rats with Streptococcus pneumoniae meningitis
10.3969/j.issn.1000-484X.2024.06.010
- VernacularTitle:糖皮质激素对肺炎链球菌脑膜炎大鼠脑保护作用及脑脊液免疫球蛋白水平的影响研究
- Author:
Linting XIAO
1
;
Shaolong ZHOU
;
Hui ZHOU
;
Yiqiu CAI
;
Wei CHEN
Author Information
1. 三亚市人民医院神经内科,三亚 572000
- Keywords:
Streptococcus pneumoniae meningitis;
Glucocorticoids;
Immunoglobulins
- From:
Chinese Journal of Immunology
2024;40(6):1172-1177
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effect of glucocorticoids on brain injury in rats with Streptococcus pneumoniae(SP)meningitis,as well as the changes of cerebrospinal fluid immunoglobulin levels under this effect.Methods:A total of 40 SD rats were divided into control group,model group,low-dose methylprednisolone sodium succinate group(Low-MSS)and high-dose methylpred-nisolone sodium succinate group(High-MSS)according to random table method,with 10 rats in each group.Except for the control group,SP meningitis models were established in other groups.Rats in Low-MSS group and High-MSS group were injected with methyl-prednisolone sodium succinate by tail vein at doses of 5 mg/kg and 10 mg/kg,respectively,once a day for 21 days.Neurobehavioral scores of rats after modeling were performed by Loeffler method;contents of immunoglobulin IgA,IgM and IgG in cerebrospinal fluid of rats were detected by immunoturbidimetry;levels of inflammatory cytokines TNF-α,IL-6 and IFN-γ in supernatant of rats brain ho-mogenate were determined by ELISA;HE staining was used to detect pathological changes of rats brain tissue;Nissl staining was used to detect the number of neuronal cells in rats brain tissue;TUNEL staining was used to detect the number of apoptotic cells in rats brain tissue;immunofluorescence staining was used to detect expressions of GFAP and S-100b,the marker proteins of rat brain tissue injury.Results:Before SP injection,there was no difference in neurobehavioral scores between control group and model group(P>0.05),at 24 h,48 h and 72 h after SP injection,neurobehavioral scores in model group were significantly lower than those in control group(P<0.05).Compared with control group,contents of IgA,IgM and IgG in cerebrospinal fluid of rats in model group were in-creased,and contents of TNF-α,IL-6 and IFN-γ in supernatant of the brain homogenate were also increased,the tissue was obviously damaged,accompanied by a large number of inflammatory cells infiltration,the number of neuronal cells were decreased,the number of apoptotic cells were increased,and the fluorescence density values of S-100b and GFAP were increased(P<0.05);compared with model group,contents of IgA,IgM and IgG in cerebrospinal fluid of rats in Low-MSS group and High-MSS group were decreased,and contents of TNF-α,IL-6 and IFN-γ in brain homogenate supernatant were also decreased(P<0.05),brain tissue damage was alleviated,inflammatory cell infiltration was significantly reduced,neuronal cells were increased,the number of apoptotic cells were decreased,and the fluorescence density values of S-100b and GFAP were also decreased(P<0.05).In addition,the improvement effect of various indexes and brain tissue damage in High-MSS group was better than that in Low-MSS group,and the difference were statistically signifi-cant(P<0.05).Conclusion:Glucocorticoid methylprednisolone sodium succinate can effectively improve the brain tissue damage in SP meningitis rats,regulate the levels of immunoglobulin IgA,IgM and IgG,and has a protective effect on SP meningitis rats.
