[關(guān)鍵詞]
[摘要]
目的 觀察芍甘木瓜湯對腦卒中偏癱痙攣狀態(tài)大鼠神經(jīng)行為學(xué)的影響,并探討對腦源性神經(jīng)營養(yǎng)因子(BDNF)/酪氨酸蛋白激酶B(TrkB)/環(huán)磷腺苷效應(yīng)元件結(jié)合蛋白(CREB)信號通路的調(diào)控機制。方法 取50只SD大鼠采用改良線栓法制作大腦中動脈梗死模型,選取建模成功大鼠隨機分為模型組、巴氯芬(0.008 g/kg)組和芍甘木瓜湯低、中、高劑量(0.05、0.10、0.15 g/kg)組。另取10只SD大鼠不栓塞大腦中動脈作為假手術(shù)組,于再灌注2 h后ig給藥,每天1次,連續(xù)2周,假手術(shù)組和模型組ig等量生理鹽水。干預(yù)前后分別采用Zea Longa量表、改良Ashworth量表評價神經(jīng)行為學(xué)、肌張力變化,采用大鼠多導(dǎo)生理記錄儀測定上肢伸直幅度;酶聯(lián)免疫法檢測大鼠干預(yù)前后血清BDNF、TrkB水平;蘇木素-伊紅(HE)染色觀察缺血半暗帶腦組織病理變化,透射電鏡下觀察缺血半暗帶腦組織神經(jīng)元超微結(jié)構(gòu);實時熒光定量PCR(qRT-PCR)檢測缺血半暗帶腦組織BDNF、TrkB-FL、TrkB-T1、CREB mRNA表達;Western blotting檢測BDNF、TrkB-FL、TrkB-T1、CREB蛋白表達及p-CREB水平。結(jié)果 干預(yù)后巴氯芬組和芍甘木瓜湯各劑量組的Zea Longa量表、改良Ashworth量表分級均較干預(yù)前和模型組(干預(yù)后)顯著改善(P<0.05),上肢伸直幅度均較干預(yù)前和模型組(干預(yù)后)均顯著增加(P<0.05),血清BDNF、TrkB水平均較干預(yù)前和模型組(干預(yù)后)顯著升高(P<0.05),缺血半暗帶腦組織病理變化和神經(jīng)元超微結(jié)構(gòu)均較模型組明顯改善。模型組缺血半暗帶腦組織BDNF、TrkB-FL mRNA與蛋白表達,p-CREB蛋白水平均顯著低于假手術(shù)組(P<0.05),巴氯芬組和芍甘木瓜湯各劑量組均較模型組顯著升高(P<0.05);模型組缺血半暗帶腦組織TrkB-T1 mRNA與蛋白表達顯著高于假手術(shù)組(P<0.05),巴氯芬組和芍甘木瓜湯各劑量組均較模型組顯著下降(P<0.05)。各組缺血半暗帶腦組織CREB mRNA表達差異無統(tǒng)計學(xué)意義。結(jié)論 對腦卒中偏癱痙攣狀態(tài)大鼠ig予以芍甘木瓜湯可改善其神經(jīng)行為學(xué),降低肌張力,增加血清BDNF、TrkB水平,減輕缺血半暗帶腦組織病理和神經(jīng)元超微結(jié)構(gòu)變化,推測與激活BDNF/TrkB/CREB通路,上調(diào)BDNF、TrkB-FL mRNA與蛋白表達,下調(diào)TrkB-T1 mRNA與蛋白表達,增加p-CREB水平有關(guān)。
[Key word]
[Abstract]
Objective To observe the effect of Shaogan Mugua Decoction on neuroethology in rats with hemiplegia spasticity after stroke, and to explore the regulation mechanism of brain-derived neurotrophic factor (BDNF)/tyrosine protein kinase B (TrkB)/camp effector element binding protein (CREB) signal pathway. Methods Totally 50 SD rats were randomly divided into model group, baclofen group, low, medium and high concentration groups of Shaogan Mugua decoction. Another 10 SD rats were taken without middle cerebral artery embolization, which were recorded as sham group. The baclofen group was given 0.008 g/kg baclofen by gavage, and the low, medium and high concentration groups of Shaogan Mugua Decoction were given 0.05, 0.1 and 0.15 g/kg Shaogan Mugua Decoction respectively, and the sham group and the model group were given the same amount of normal saline, lasted for two weeks. Before and after intervention, Zea longa scale and modified Ashworth scale were used to evaluate neurobehavior and muscle tension. The range of upper limb extension was measured by multi-channel physiological recorder. The serum levels of BDNF and TrkB were detected by enzyme-linked immunosorbent assay (ELISA). Hematoxylin eosin (HE) staining was used to observe the histopathology of ischemic penumbra brain tissues. The ultrastructure of neurons of histopathology of ischemic penumbra brain tissues was observed under transmission electron microscope. Real time reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expressions of BDNF, TrkB-FL, TrkB-T1 and CREB mRNA. The expressions of BDNF, TrkB-FL, TrkB-T1, CREB and p-CREB were detected by Western blotting. Results After intervention, the scores of Zea longa scale and modified Ashworth scale in baclofen group and three dose groups of Shaogan Mugua Decoction were improved compared with those before intervention and model group (P<0.05), the extents of upper limb extension were increased compared with those before intervention and model group (P<0.05), serum BDNF and TrkB levels were increased compared with those before intervention and model group (P<0.05), the pathological changes of ischemic penumbra tissues and ultrastructure of neurons in infarcted area were improved compared with those in the model group. The expressions of BDNF, TrkB-FL mRNA and proteins, and the level of p-CREB in the model group were lower than those in the sham operation group (P<0.05), while those in the baclofen group and three dose groups of Shaogan Mugua Decoction were increased compared with those in model group (P<0.05). The expression of TrkB-T1 mRNA and protein in the model group was higher than that in the sham group (P<0.05), while those in the baclofen group and three dose groups of Shaogan Mugua Decoction were decreased compared with that in the model group (P<0.05). There was no significant difference in the expression of CREB mRNA in the ischemic penumbra tissues among the three groups. Conclusion Shaogan Mugua Decoction can improve neurobehavior, decrease muscle tension, and increase serum BDNF and TrkB levels in rats with hemiplegic spasticity after stroke. It is speculated that it is related to activating BDNF/TrkB/CREB pathway, up regulating the mRNA and protein expressions of BDNF and TrkB-FL, down regulating the mRNA and protein expressions of TkrB-T1, and increasing the level of p-CREB.
[中圖分類號]
R285.5
[基金項目]
湖北省教育廳科學(xué)研究計劃指導(dǎo)性項目(B2018098)