Effect and mechanism of ammonium pyrrolidine dithiocarbamate on neuroinflammation in rats with traumatic brain injury
10.7683/xxyxyxb.2024.07.006
- VernacularTitle:吡咯烷二硫代氨基甲酸铵对创伤性脑损伤大鼠神经炎症的作用及机制
- Author:
Jiafa YANG
1
;
Zhaofeng LU
;
Yaqiong WANG
;
Ruoyu LU
;
Hairong LI
;
Mengjia LIU
Author Information
1. 河南科技大学第一附属医院/河南科技大学临床医学院,河南 洛阳 471003
- Keywords:
traumatic brain injury;
ammonium pyrrolidine dithiocarbamate;
neuroinflammatory injury;
nuclear transcrip-tion factor
- From:
Journal of Xinxiang Medical College
2024;41(7):631-639
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect and mechanism of ammonium pyrrolidine dithiocarbamate(PDTC)on neuroinflammatory injury in the penumbra of traumatic brain injury(TBI)in rats.Methods Sixty Sprague Dawley rats were divided into the PDTC group,TBI group,sham operation group and control group according to the random number table method,with 15 rats in each group.Rats in the PDTC group were intraperitoneally injected with PDTC(100 mg·kg-1)at 15 minutes before surgery;while the rats in the TBI group,sham operation group,and control group were intraperitoneally injected with the same volume of double distilled water.After the cranial window of rats in the TBI group and PDTC group was created,a 2.5 g steel rod with an inner diameter of 6.0 mm was dropped freely from a height of 75 cm through a transparent polyvinyl chloride tube with an inner diameter of 7.0 mm to impact the dura mater and induce right parietal lobe contusion and laceration to establish the TBI model;rats in the sham operation group were sealed with bone wax after the cranial window creation,without any impact applied;rats in the control group were raised under normal conditions.The modified neurological severity score(mNSS)was used to evaluate the degree of neurobehavioral damage in rats in each group at 1,4 and 7 days after modeling.At 2 days after modeling,5 rats in each group were decapitated,and brain tissues were taken for hematoxylin & eosin(HE)staining,and morphological changes of the brain tissues were observed under an optical microscope.The expressions of β-amyloid precursor protein(β-APP)and glial fibrillary acidic protein(GFAP)in the brain tissues of rats in each group were detected by immunohistochemical staining.At 24 hours after modeling,5 rats in each group were decapitated,and the right injured penumbra tissues were obtained;the expressions of nuclear transcription factor-κB(NF-κB)P65,phosphorylated NF-κB P65,inhibitor of NF-κB(IκB),phosphorylated IKB,NOD-like receptor protein 3(NLRP3)and caspase-1 protein in the right injured penumbra tissue of rats in each group were detected by Western blot,and the expressions of NF-κB P65,IκB,NLRP3 and caspase-1 mRNA in the right injured penumbra tissue of rats in each group were determined by real-time quantitative polymerase chain reaction.Results At 1,4,and 7 days after modeling,the mNSS scores of rats in the TBI group were signifi-cantly higher than those in the PDTC group,control group and sham operation group.The mNSS scores of rats in the PDTC group were significantly higher than those in the control group and sham operation group(P＜0.05);there was no statistically significant difference in mNSS scores between the sham operation group and the control group(P＞0.05).The neurons and neurogliocyte of rats in the control group and the sham operation group exhibited normal morphology,without swelling and wide-ning of intercellular space.Diffuse hemorrhagic changes were observed in the brain tissues of rats in the TBI group,with different morphologies of neuronal cell body,unclear cell membrane and cytoplasm,pyknosis of cell nuclei,often triangular shape,disappearance of normal structure and nucleoli,and diffuse white blood cells and red blood cells filling the field of vision.The lesion surrounding area of rats in the PDTC group showed ischemic changes,with mild shrinkage of neuronal volume,a uniform light red color,karyopyknosis,nuclear-cytoplasmic dissociation,disappearance of normal structure and nucleoli,and localization of neuroinflammation.There was no significant expression of β-APP and GFAP in the cerebral cortex of rats in the control group and the sham operation group,while the accumulation of β-APP and GFAP in neuronal serosae and/or axons was observed in the brain tissues of rats in the TBI group and the PDTC group.Compared with the TBI group,a decrease in the number and the expression intensity of β-APP and GFAP-positive stained neuronal cells in the cerebral cortex of rats was observed in the PDTC group.The relative expression of NF-κB P65 protein in the brain tissues of rats in the sham operation group,TBI group and PDTC group was significantly higher than that in the control group,and the relative expression of NF-κB P65 protein in the brain tissues of rats in the PDTC group was significantly higher than that in the TBI group(P＜0.05).The relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the PDTC group and the sham operation group was significantly lower than that in the control group,the relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the TBI group was significantly higher than that in the control group and the sham operation group,and the relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the PDTC group was significantly lower than that in both TBI group and sham operation group(P＜0.05).There was no significant difference in the relative expression of IκB protein in the brain tissues of rats between the sham operation group and the control group(P＞0.05);the relative expression of IκB protein in the brain tissues of rats in the TBI group was significantly higher than that in the control group,and the relative expression of IκB protein in the brain tissues of rats in the PDTC group was significantly lower than that in the control group,sham operation group,and TBI group(P＜0.05).The relative expression of phosphorylated IκB protein in the brain tissues of rats in the TBI group was significantly lower than that in the control group and the sham operation group,and the relative expression of phosphorylated IκB protein in the brain tissues of rats in the PDTC group was significantly higher than that in the TBI group(P＜0.05).The relative expression of NLRP3 protein in the brain tissues of rats in the sham opera-tion group was significantly higher than that in the control group,the relative expression of NLRP3 protein in the brain tissues of rats in the TBI group and the PDTC group was significantly lower than that in the sham operation group and the control group,and the relative expression of NLRP3 protein in the brain tissues of rats in the TBI group was significantly lower than that in the PDTC group(P＜0.05).The relative expression of caspase-1 protein in the brain tissues of rats in the sham opera-tion group,PDTC group,and TBI group was significantly higher than that in the control group,and the relative expression of caspase-1 protein in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group,TBI group,and sham operation group was significantly higher than that in the control group,the relative expression of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expres-sion of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of IκB mRNA in the brain tissues of rats in the PDTC group and TBI group were signifi-cantly higher than that in the control group,and the expression of IκB mRNA in the brain tissues of rats in the sham operation group was significantly lower than that in the control group(P＜0.05).The relative expression of IκB mRNA in the brain tis-sues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expression of IκB mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the control group,the relative expression of NLRP3 mRNA in the brain tissues of rats in the sham operation group was significantly lower than that in the control group,the relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of caspase-1 mRNA in the brain tissues of rats in the sham operation group,TBI group,and PDTC group was significantly lower than that in the control group,the relative expression of caspase-1 mRNA in the brain tissues of rats in the TBI group and PDTC group was significantly higher than that in the sham operation group(P＜0.05).Conclusion PDTC can effectively improve neural functional deficit score and reduce neuroinflammatory injury in TBI rats,the mechanism of which may be related to regulating mRNA and protein expression of NF-κB/NLRP3 axis-related inflammatory injury indicators and regulating downstream inflammatory factors.
