摘要
目的探究诺卡酮(NKT)对轻度脑爆震伤(bTBI)大鼠抑郁样行为的缓解作用及其机制。方法采用生物激波管分别模拟爆炸超压(BOP)为60 kPa、90 kPa和120 kPa的冲击波建立大鼠bTBI抑郁样模型。BOP暴露后14 d,采用悬尾实验及强迫游泳实验对大鼠抑郁样行为进行评估,选取抑郁样行为最为明显的BOP(120 kPa)进行后续实验。30只大鼠随机分为假手术组、bTBI组(120 kPa BOP暴露)、bTBI+NKT组[120 kPa BOP暴露后第1天开始,经口给药给予NKT 10 mg/(kg·d),共14 d],每组10只。BOP暴露后14 d,采用悬尾实验及强迫游泳实验对大鼠抑郁样行为进行评估;采用Western blotting检测海马组织中蛋白激酶A(PKA)、磷酸化环磷腺苷效应元件结合蛋白(pCREB)及脑源性神经营养因子(BDNF)的表达水平;免疫组化检测海马齿状回区(DG)增殖细胞核抗原(PCNA)标记的神经发生情况。结果90 kPa的BOP暴露即可引起大鼠抑郁样行为,而120 kPa组大鼠BOP暴露后产生的抑郁样行为更明显(P<0.05),据此选取120 kPa的BOP暴露进行后续实验。BOP暴露后14 d,与假手术组比较,bTBI组大鼠悬尾实验不动时间延长(P<0.05),强迫游泳实验潜伏期缩短,不动时间延长(P<0.05),海马组织中PKA、pCREB和BDNF蛋白表达水平降低(P<0.05),海马DG区PCNA阳性神经元数量减少(P<0.05);与bTBI组比较,bTBI+NKT组大鼠悬尾实验不动时间缩短(P<0.05),强迫游泳实验潜伏期延长,不动时间缩短(P<0.05),海马组织中PKA、pCREB和BDNF蛋白表达水平升高(P<0.05),海马DG区PCNA阳性神经元数量增加(P<0.05)。结论早期给予NKT治疗可缓解轻度bTBI大鼠的抑郁样行为,其机制可能与NKT通过激活海马PKA/CREB/BDNF信号通路,使pCREB和BDNF表达水平上调,进而促进海马DG区神经发生有关。
Objective To investigate the mechanism of nootkatone(NKT)in mitigating depression-like behavior caused by blast traumatic brain injury(TBI).Methods The rat bTBI depression-like model was established by simulating the shock wave parameters of blast overpressure(BOP of 60 kPa,90 kPa,and 120 kPa)with a biological shock wave tube.After 14 days of exposure,we evaluated the depression-like behavior of rats using the tail suspension test and forced swimming test.We identified that the BOP(120 kPa)condition caused the most noticeable depressive behavior and used this condition for subsequent experiments.Thirty male SD rats were randomly divided into sham operation group,bTBI group(BOP of 120 kPa),and bTBI+NKT group[at 1 d after exposure to BOP of 120 kPa,giving NKT 10 mg/(kg·d)orally for 14 days],10 in each group.After 14 days of exposure,the depression-like behavior of rats was evaluated by tail suspension test and forced swimming test.The expression levels of protein kinase A(PKA),phosphorylated cyclic adenosine monophosphate effector binding protein(pCREB),and brain-derived neurotrophic factor(BDNF)in the hippocampus of rat were determined by Western blotting.Immunohistochemistry was used to detect the generation of proliferating cell nuclear antigen(PCNA)-labeled neurons in the hippocampal dentate gyrus(DG).Results BOP of 90 kPa can cause depression-like in rats and BOP of 120 kPa can cause the most noticeable depressive behavior(P<0.05).Therefore,we selected the BOP exposure of 120 kPa for subsequent experiments.After 14 days of BOP exposure,compared with sham operation group,the immobility time of tad suspension test in bTBI group was prolonged(P<0.05),the latency of for ced swimming test was shortened,the immobility time was prolonged(P<0.05),the expression levels of PKA,pCREB and BDNF protein in hippocampus were lowered(P<0.05),and the number of PCNA-labeled neurons in hippocampal DG area was reduced(P<0.05);compared with the bTBI group,the immobility time of tail suspension test in bTBI+NKT group was shortened(P<0.05),the latency of forced swimming test was prolonged,the immobility time was shortened(P<0.05),the expression levels of PKA,pCREB and BDNF protein in hippocampus were increased(P<0.05),and the number of PCNA-labeled neurons in hippocampal DG area was increased(P<0.05).Conclusions Early treatment with NKT can improve depression-like behavior in mild bTBI rats.The mechanism may be related to the up-regulation of the PKA-CREB-BDNF signaling pathway and increased expression levels of pCREB and BDNF in the hippocampus,which results in increased neuron numbers in the DG region of the hippocampus.
作者
范小琳
王鸿
王琪
李存治
卢青
李亮
马宁
高俊宏
Fan Xiao-Lin;Wang Hong;Wang Qi;Li Cun-Zhi;Lu Qing;Li Liang;Ma Ning;Gao Jun-Hong(Institute for Hygiene of Ordnance Industry,Xi'an,Shaanxi 710065,China)
出处
《解放军医学杂志》
CAS
CSCD
北大核心
2024年第6期694-700,共7页
Medical Journal of Chinese People's Liberation Army
基金
陕西省自然科学基金项目(2023-JC-QN-0983,2023-JC-YB-684)。
