于秋紅,郁軍超,吉康祥,劉亞玲,薛連璧
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大劑量高壓氧對腦梗死大鼠細胞色素C及caspase-3的影響
于秋紅,郁軍超,吉康祥,劉亞玲,薛連璧
[摘要]目的觀察單次高壓氧(HBO)治療9 h對永久性大腦中動脈阻塞(MCAO)大鼠細胞色素C和caspase-3水平的影響。方法48只Sprague-Dawley大鼠制作永久性MCAO模型,分為對照組(n=24)和高壓氧組(n=24),高壓氧組大鼠于造模成功后3 h予單次高壓氧治療9 h,壓力0.2 MPa。于造模成功后3 h、13 h、24 h行大鼠Garcia神經(jīng)功能評分,于造模成功后13 h、24 h TUNEL法檢測大鼠腦組織細胞凋亡數(shù),ELISA法檢測缺血半暗帶腦組織細胞色素C及活性caspase-3水平。結(jié)果兩組大鼠造模成功后13 h、24 h神經(jīng)功能均有明顯改善,兩組間無顯著性差異(t<2.07,P>0.05)。兩組造模成功后13 h、24 h均見凋亡細胞,高壓氧組明顯少于對照組(t>6.57,P<0.01)。高壓氧組細胞色素C和caspase-3的水平在造模成功后24 h低于對照組(t>2.41,P<0.05)。結(jié)論大劑量高壓氧超早期治療可降低腦缺血后細胞色素C和caspase-3水平,減少細胞凋亡,可能是高壓氧治療腦梗死的機制之一。
[關(guān)鍵詞]腦梗死;高壓氧;細胞色素C;caspase-3;凋亡;大鼠
[本文著錄格式]于秋紅,郁軍超,吉康祥,等.大劑量高壓氧對腦梗死大鼠細胞色素C及caspase-3的影響[J].中國康復理論與實踐,2016,22(5):540-543.
作者單位:首都醫(yī)科大學附屬北京天壇醫(yī)院高壓氧科,北京市100050。
腦梗死的治療策略主要是盡快恢復缺血區(qū)域的血流和給予神經(jīng)保護治療[1]。有研究提示,高壓氧(hyperbaric oxygenation,HBO)治療能促進腦新生血管的形成和側(cè)支循環(huán)的建立[2-3],且有直接神經(jīng)保護作用[4],能保護缺血半暗帶可存活腦細胞[5]。我們前期實驗提示,大劑量高壓氧超早期治療永久性大腦中動脈阻塞(middle cerebral artery occlusion,MCAO)大鼠,可能通過提高內(nèi)源性血管內(nèi)皮生長因子(vascular endo-thelial growth factor,VEGF),促進側(cè)支循環(huán)建立,減小腦梗死體積,從而抑制、阻斷,甚至逆轉(zhuǎn)腦缺血后病理變化[6]。高壓氧治療可通過抑制腦梗死大鼠線粒體膜電位(mitochondrial membrane potential,MMP)降低,減少細胞凋亡[7]。我們采用高壓氧單次9 h方案,超早期治療局部腦梗死大鼠,觀察高壓氧對大鼠凋亡相關(guān)分子細胞色素C和caspase-3水平的影響。
1.1實驗動物
清潔級雄性Sprague-Dawley大鼠48只,體質(zhì)量(280±20)g,由北京維通利華實驗動物技術(shù)有限公司提供。術(shù)前大鼠禁食不禁水3 h以上。
1.2試劑
水合氯醛、蔗糖:北京化學試劑公司。多聚甲醛(Cat#KGT558)、磷酸鹽緩沖液(Phosphate Buffered Saline,PBS,Cat#KGT549)、檸檬酸鈉(Cat#KGT553)、聚乙二醇辛基苯基醚(Triton X-100,Cat#KGT551)、TUNEL試劑盒(Cat#KGA7044,含緩沖液、熒光素標記的脫氧尿嘧啶核苷三磷酸、脫氧核糖核苷酸末端轉(zhuǎn)移酶、抗熒光素抗體、辣根過氧化酶底物二氨基聯(lián)苯胺顯色劑)、線粒體/細胞核提取試劑盒(Cat#KGA828):南京凱基生物科技發(fā)展有限公司。大鼠細胞色素C ELISA試劑盒、大鼠caspase-3 ELISA試劑盒:美國RB公司。
1.3模型制作及分組
采用改良Longa線栓法[8]永久性阻塞大鼠左側(cè)大腦中動脈。術(shù)后3 h采用姿勢反射試驗進行行為學評分(3分制)[9],評分≥1分的動物視為造模成功,排除麻醉未清醒、死亡、無自主行動大鼠和無神經(jīng)功能缺損大鼠。造模成功的大鼠分為對照組(n=24)和高壓氧組(n=24)。
1.4方法
高壓氧組動物于MCAO后3 h開始高壓氧治療。采用透明純氧動物實驗艙(上海減壓器廠),壓力0.2 MPa,升壓20 min,穩(wěn)壓9 h,減壓40 min。為避免氧中毒,大鼠于第1、3、5、7、9小時呼吸純氧,第2、4、6、8小時呼吸高壓空氣。對照組MCAO后呼吸常壓空氣。
1.5觀察指標
1.5.1神經(jīng)功能評分
采用Garcia評分[10]于MCAO后3 h、13 h、24 h對大鼠進行行為學評分。
1.5.2TUNEL染色
于MCAO后13 h、24 h,每組取6只大鼠10A水合氯醛3 ml/kg腹腔注射麻醉,生理鹽水、4A甲醛灌殺,取前囟后3~6 mm處腦組織冰凍切片,厚20 μm,TUNEL染色。冰凍切片浸入通透液,冰上促滲2 min,PBS沖洗3次,滴加脫氧核糖核苷酸末端轉(zhuǎn)移酶反應液,濕盒中37℃反應60 min,PBS沖洗3次。熒光顯微鏡觀察,每只大鼠選5個視野,計數(shù)陽性細胞數(shù),取平均數(shù)。
1.5.3ELISA染色
于MCAO后13 h、24 h,每組取6只大鼠,斷頭取腦,將缺血半暗帶腦組織[11]剪成糊糜,使用線粒體/細胞核提取試劑盒,全程低溫操作,漂洗、研磨、多次離心制成胞漿提取液,采用細胞色素C和caspase-3 ELISA試劑盒,按說明書步驟操作,檢測細胞色素C 和caspase-3含量。
1.6統(tǒng)計學分析
采用SPSS 16.0統(tǒng)計軟件分析。計量資料符合正態(tài)分布,以表示,兩兩比較采用獨立樣本t檢驗。顯著性水平α=0.05。
2.1神經(jīng)功能評分
與MCAO后3 h相比,各組大鼠13 h時評分明顯增加(P<0.01),但24 h時沒有進一步的改善。高壓氧組評分較對照組雖有提高的趨勢,但無顯著性差異(P>0.05)。見表1。
2.2凋亡細胞數(shù)
兩組大鼠缺血半暗帶區(qū)可見大量凋亡細胞,高壓氧組較對照組明顯減少(P<0.01),高壓氧組24 h較13 h時凋亡細胞數(shù)明顯減少(P<0.01)。見表2。
2.3細胞色素C
細胞色素C在MCAO后13 h可見,兩組水平相近。24 h時,對照組細胞色素C水平繼續(xù)增高,而高壓氧組有下降趨勢,較對照組明顯降低。見表3。
2.4caspase-3
對照組caspase-3水平在13 h增高(正常時胞漿內(nèi)水平為0),在24 h仍處于高位水平,而高壓氧組caspase-3水平在24 h下降,較13 h及對照組皆降低。見表4。
表1 各組大鼠Garcia評分比較
表2 各組TUNEL陽性細胞計數(shù)比較
表3 各組細胞色素C水平比較(pg/ml)
表4 各組caspase-3水平比較(μmol/ml)
高壓氧治療MCAO模型的療效存在爭議[12-14],高壓氧治療開始的時間和劑量是關(guān)鍵[15]。本研究和前期結(jié)果[6-7,16]類似,顯示單次9 h高壓氧能改善局部腦梗死大鼠的神經(jīng)功能,減少細胞凋亡。原因可能是缺血周圍區(qū)存在部分休眠細胞,高壓氧提供充足的氧氣,挽救部分休眠細胞,并使不可挽救的細胞發(fā)生凋亡而非壞死,避免梗死進一步擴大,從而改善神經(jīng)功能。
細胞色素C是第一種被發(fā)現(xiàn)的與線粒體有關(guān)的促凋亡因子。本研究顯示,腦缺血后凋亡細胞、細胞色素C和caspase-3出現(xiàn);大劑量高壓氧治療后,缺血半暗帶區(qū)凋亡細胞減少,作用可持續(xù)到缺血后24 h;這一過程伴有細胞色素C和caspase-3水平降低。其機制可能是高壓氧穩(wěn)定了線粒體膜電位[7],不僅提供充足ATP[17-19],而且抑制缺血后細胞色素C等凋亡相關(guān)物質(zhì)釋放[20],從而減少內(nèi)源性凋亡途徑激活[21]。
大鼠在體研究證實,高壓氧通過線粒體途徑引起外周血淋巴細胞凋亡,抑制早期急性胰腺炎的炎性反應[22]。機制包括凋亡誘導因子[23]轉(zhuǎn)位、神經(jīng)蛋白[24]等。我們此前的研究也證實,高壓氧可通過線粒體途徑影響細胞凋亡[7]。體外研究發(fā)現(xiàn),30 min高壓氧暴露可通過線粒體機制導致T淋巴細胞凋亡[25]。當然,高壓氧也可通過非線粒體途徑影響細胞凋亡。
本研究尚存以下局限。首先是觀察時點較少,觀察時間較短,可能不足以反映腦梗死過程中各指標演變的完整過程;其次,由于缺血半暗帶是一個動態(tài)變化的區(qū)域,取材定位的缺血半暗帶與實際的缺血半暗帶可能存在差距。
[參考文獻]
[1]Griessenauer CJ,F(xiàn)oreman P,Deveikis JP,et al.Endovascular tools available for the treatment of cerebrovascular disease[J]. Neurosurg Clin NAm,2014,25(3):387-394.
[2]Peng ZR,Yang AL,Yang QD.The effect of hyperbaric oxygen on intracephalic angiogenesis in rats with intracerebral hemorrhage[J].J Neurol Sci,2014,342(1-2):114-123.
[3]Duan S,Shao G,Yu L,et al.Angiogenesis contributes to the neuroprotection induced by hyperbaric oxygen preconditioningagainst focal cerebral ischemia in rats[J].Int J Neurosci,2015,125(8):625-634.
[4]Matchett GA,Martin RD,Zhang JH.Hyperbaric oxygen therapy and cerebral ischemia:neuroprotective mechanisms[J]. Neurol Res,2009,31(2):114-121.
[5]Li JS,Zhang W,Kang ZM,et al.Hyperbaric oxygen preconditioning reduces ischemia-reperfusion injury by inhibition of apoptosis via mitochondrial pathway in rat brain[J].Neuroscience,2009,159(4):1309-1315.
[6]于秋紅,張紅霞,劉亞玲,等.單次9小時高壓氧超早期治療對大鼠腦梗死體積的影響[J].中國卒中雜志,2008,3(9): 662-666.
[7]于秋紅,李婕,劉亞玲,等.大劑量高壓氧超早期治療對局部腦梗死大鼠細胞凋亡的影響[J].中國卒中雜志,2014,9(9): 762-766.
[8]Longa EZ,Weinstein PR,Carlson S,et al.Reversible middle cerebral artery occlusion without cranitonomy in rats[J]. Stroke,1989,20(1):84-91.
[9]Zhang L,Schallert T,Zhang ZG,et al.A test for detecting long-term sensorimotor dysfunction in the mouse after focal cerebral ischemia[J].J Neurosci Method,2002,117(2): 207-214.
[10]Garcia JH,Wagner S,Liu KF,et al.Neurological deficit and extent of neuronal necrosis attributable to middle cerebral artery occlusion in rats.Statistical validation[J].Stroke,1995,26 (4):627-635.
[11]Ashwal S,Tone B,Tian HR,et al.Core and penumbral nitric oxide synthase activity during cerebral ischemia and reperfusion[J].Stroke,1998,29(5):1037-1047.
[12]李綱,張志強,張立新.即時高壓氧對大鼠局灶性腦缺血后梗死體積的影響[J].中國康復理論與實踐,2015,21(1):39-41.
[13]Rusyniak DE,Kirk MA,May JD,et al.Hyperbaric oxygen therapy in acute ischemic stroke:results of the Hyperbaric Oxygen in Acute Ischemic Stroke Trial Pilot Study[J].Stroke,2003,34(2):571-574.
[14]Lu Y,Kang J,Bai Y,et al.Hyperbaric oxygen enlarges the area of brain damage in MCAO rats by blocking autophagy via ERK1/2 activation[J].Eur J Pharmacol,2014,728:93-99.
[15]王曉紅,黃禮群,龔琴,等.不同時間窗及療程的高壓氧治療對急性腦梗死的影響[J].重慶醫(yī)學,2011,40(31):3140-3142.
[16]于秋紅,劉亞玲,吳雅麗,等.單次9h高壓氧超早期治療局部腦梗死大鼠療效探討[J].山東醫(yī)藥,2008,48(37):36-38.
[17]Nicotera P,Leist M,F(xiàn)errando-May E.Intracellular ATP,a switch in the decision between apoptosis and necrosis[J].Toxicol Lett,1998,102-103:139-142.
[18]Zhou SH,Sun YF,Wang G.Effects of hyperbaric oxygen on intestinal mucosa apoptosis caused by ischemia-reperfusion injury in rats[J].World J Emerg Med,2012,3(2):135-140.
[19]Sun L,Strelow H,Mies G,et al.Oxygen therapy improves energy metabolism in focal cerebral ischemia[J].Brain Res,2011,1415:103-108.
[20]Wang L,Li W,Kang Z,et al.Hyperbaric oxygen preconditioning attenuates early apoptosis after spinal cord ischemia in rats[J].J Neurotrauma,2009,26(1):55-66.
[21]Xu S,Liu J,Zhang Y,et al.Apoptosis-related protein expression in rabbits with blast brain injury following early hyperbaric oxygen therapy[J].Neural Regen Res,2012,7(17): 1318-1324.
[22]Bai X,Song Z,Zhou Y,et al.The apoptosis of peripheral blood lymphocytes promoted by hyperbaric oxygen treatment contributes to attenuate the severity of early stage acute pancreatitis in rats[J].Apoptosis,2014,19(1):58-75.
[23]Li H,Chen G,Ma W,et al.Water-soluble coenzyme q10 inhibits nuclear translocation of apoptosis inducing factor and cell death caused by mitochondrial complex I inhibition[J].Int J Mol Sci,2014,15(8):13388-13400.
[24]Liu J,Yu Z,Guo S,et al.Effects of neuroglobin overexpression on mitochondrial function and oxidative stress following hypoxia/reoxygenation in cultured neurons[J].J Neurosci Res,2009,87(1):164-170.
[25]Weber SU,Koch A,Kankeleit J,et al.Hyperbaric oxygen induces apoptosis via a mitochondrial mechanism[J].Apoptosis,2009,14(1):97-107.
·綜述·
CITED AS:Yu QH,Yu JC,Ji KX,et al.Effect of intensive hyperbaric oxygenation on cytochrome C and caspase-3 in rats after focal cerebral infarction[J].Zhongguo Kangfu Lilun Yu Shijian,2016,22(5):540-543.
Effect of Intensive Hyperbaric Oxygenation on Cytochrome C and Caspase-3 in Rats after Focal Cerebral Infarction
YU Qiu-hong,YU Jun-chao,JI Kang-xiang,LIU Ya-ling,XUE Lian-bi
Department of Hyperbaric Oxygen,Beijing Tiantan Hospital,Capital Medical University,Beijing 100050,China
Correspondence to XUE Lian-bi.E-mail:xue40@vip.sina.com
Abstract:Objective To observe the effect of single intensive hyperbaric oxygenation(HBO)on cytochrome C and caspase-3 in rats after permanent middle cerebral artery occlusion(MCAO)very early.Methods Forty-eight male Sprague-Dawley rats were subjected to permanent MCAO model using the intraluminal suture method,and were divided into control group(n=24)and HBO group(n=24).The HBO group stayed in the hyperbaric cabin with a pressure of 0.2 MPa for 9 hours 3 hours after MCAO.They were measured with Garcia scores 3 hours,13 hours and 24 hours after MCAO.Apoptosis cells of ischemic penumbra tissue were investigated with TUNEL 13 hours and 24 hours after MCAO,while the level of cytochrome C and caspase-3 were measured with ELISA.Results The Garcia scores increased 13 hours and 24 hours after MCAO in both groups,but there was no significant difference between groups(t<2.07,P>0.05).The apoptosis cells were found in both groups 13 hours and 24 hours after MCAO,and less in the HBO group than in the control group(t>6.57,P<0.01). The levels of cytochrome C and caspase-3 were less in the HBO group than in the control group 24 hours after MCAO(t>2.41,P<0.05). Conclusion A single intensive HBO in very early stage may improve neurological function after cerebral ischemia in rats,which may associate with the inhibition of cytochrome C and caspase-3 to reduce cell apoptosis.
Key words:cerebral infarction;hyperbaric oxygen;cytochrome C;caspase-3;apoptosis;rats
DOI:10.3969/j.issn.1006-9771.2016.05.011
[中圖分類號]R743.32
[文獻標識碼]A
[文章編號]1006-9771(2016)05-0540-04
作者簡介:于秋紅(1977-),女,漢族,河北遷西縣人,博士,副主任醫(yī)師,主要研究方向:高壓氧神經(jīng)病學,神經(jīng)系統(tǒng)疾病的早期治療和康復。通訊作者:薛連璧,男,博士,主任醫(yī)師。E-mail:xue40@vip.sina. com。
收稿日期:(2015-10-12修回日期:2016-03-03)