[摘要] 目的 研究δ阿片受體激動(dòng)劑DADLE(D-Ala2-D-Leu5-enkephalin)對(duì)膿毒癥大鼠肝組織高遷移率族蛋白1(HMGB1)水平的影響。 方法 將96只Sprague-Dawley(SD)大鼠分為假手術(shù)組(SO)、膿毒癥組(SEP)、DADLE組[制模后立即給藥DADLE(5mg/kg,腹腔內(nèi)注)], 每組32只。采用改良盲腸結(jié)扎穿孔方法(CLP)建立大鼠膿毒癥模型,于制模后6 h,12 h,18 h,24 h每組各取8只處死取材, Western Blot法檢測(cè)肝組織HMGB1水平。 結(jié)果 12 h 時(shí)SEP組和DADLE組HMGB1水平與SO組相比均明顯升高(P < 0.05),且DADLE組明顯低于SEP組(P < 0.05);18 h時(shí)SEP組和DADLE組HMGB1水平達(dá)到最高。同樣DADLE組明顯低于SEP組(P < 0.05);24 h時(shí)SEP組和DADLE組HMGB1水平較18 h有所降低,但DADLE組仍明顯低于SEP組(P < 0.05)。 結(jié)論 DADLE能明顯降低膿毒癥大鼠肝組織HMGB1水平。
[關(guān)鍵詞] DADLE;膿毒癥;高遷移率族蛋白1
[中圖分類號(hào)] R826.3 [文獻(xiàn)標(biāo)識(shí)碼] A [文章編號(hào)] 1673-9701(2012)03-0007-02
Effect of delta-opioid receptor agonist DADLE on liver tissue HMGB1 level in rat with sepsis
TAO Yulong TANG Chengwu FENG Wenming BAO Ying ZHU Ming
Department of Hepatobiliary Surgery and Molecular Surgery,the Huzhou Ctiy First People’s Hospital,Zhejiang Province,Huzhou 313000,China
[Abstract] Objective To study the effect of delta-opioid receptor agonist (DADLE) on liver tissue HMGB1 level in rat with sepsis. Methods All of 96 SD rats were randomly divided in to sham operated group (SO), septic group (SEP), and DADLE group(DADLE). Septic model was produced by cecal ligation and puncture (CLP). In SO group, the abdomen was opened without any other treatment. In DADLE group, DADLE was administered at a dose of 5 mL/kg by intra-peritoneal injection after CLP. Rats were sacrificed at 6 h, 12 h, 18 h and 24 h after CLP. Liver tissue HMGB1 level was determined by Western Blot. Results Liver tissue HMGB1 levels of SEP and DADLE group began to increase at 12 h, and reached the peak around 18 h after CLP. Notably, liver tissue HMGB1 levels of DADLE group at 12 h, 18 h and 24 h were significantly lowered than those of SEP group (P < 0.05). Conclusion DADLE can significantly decrease liver tissue HMGB1 level of septic rat.
[Key words] DADLE; Sepsis; High-mobility Group box 1 Protein
膿毒癥是嚴(yán)重感染、創(chuàng)傷及大手術(shù)等應(yīng)激狀況時(shí)常見的并發(fā)癥,已經(jīng)成為當(dāng)今重癥監(jiān)護(hù)室的首要死亡原因[1]。膿毒癥時(shí)多種炎癥因子參與了膿毒癥的病理過(guò)程,高遷移率族蛋白B1(high mobility group box1 protein,HMGBl)作為潛在晚期炎性因子,是膿毒癥致死效應(yīng)的重要炎性介質(zhì),是致急性肝損傷(ALI)的一種重要的細(xì)胞因子[2],干預(yù)HMGB1可有效防止MODS的發(fā)生與發(fā)展[3-4]。δ阿片受體激動(dòng)劑DADLE(D-Ala2-D-Leu5-enkephalin)是一種人工合成的非選擇性δ阿片受體激動(dòng)劑,我們以往的研究發(fā)現(xiàn)DADLE能明顯減輕膿毒癥大鼠肝組織損傷[5],本研究旨在探討其對(duì)膿毒癥大鼠肝組織HMGBl水平的影響,從而對(duì)DADLE在膿毒癥中對(duì)肝組織的保護(hù)作用進(jìn)行初步闡述。
1 材料與方法
1.1 實(shí)驗(yàn)材料
DADLE(D-Ala2-D-Leu5-enkephalin)分子式C29H39N507,購(gòu)自美國(guó)Sigma公司。
1.2 動(dòng)物分組及膿毒癥模型建立
清潔級(jí)健康SD雄性大鼠96只,體重270~320 g,由上海斯萊克實(shí)驗(yàn)動(dòng)物有限責(zé)任公司提供,隨機(jī)分為DADLE組、假手術(shù)組(SO組)和膿毒癥組(SEP組),每組32只,參照Wichterman等[6]的改良的盲腸結(jié)扎穿孔(CLP)方法建立大鼠膿毒癥模型,假手術(shù)組除不施行CLP,其余操作同SEP組,DADLE組在模型建立后立即腹腔注射濃度為0.5 mg/mL的DADLE(劑量:5mL/kg體重)。CLP后6 h、12 h、18 h、24 h每組斷頸處死8只大鼠。
1.3 肝組織HMGBl蛋白水平檢測(cè)
將肝組織蛋白轉(zhuǎn)印至硝酸纖維素膜后在封閉液中與一抗(兔抗HMGBl多克隆抗體,購(gòu)自美國(guó)BD Pharmingen公司)結(jié)合,然后與二抗(辣根過(guò)氧化物酶標(biāo)記的山羊抗兔IgG,購(gòu)自北京中山生物技術(shù)有限公司)室溫孵育。采用化學(xué)發(fā)光反應(yīng)試劑盒進(jìn)行發(fā)光,暗室曝光后底片經(jīng)圖像分析系統(tǒng)(LEICA Q-5501W,德國(guó)Leiea公司)處理,根據(jù)各條帶的吸光度值進(jìn)行定量分析。
1.4 統(tǒng)計(jì)學(xué)處理
采用SPSS10.0軟件進(jìn)行處理,計(jì)量資料以(x±s)表示,多組間比較采用方差分析,組間兩兩比較采用q檢驗(yàn),P < 0.05為差異有統(tǒng)計(jì)學(xué)意義。
2 結(jié)果
DADLE對(duì)膿毒癥大鼠肝組織HMGB1水平的影響見表1。CLP后6 h SEP和DADLE組肝組織HMGB1水平開始升高,但三組間無(wú)統(tǒng)計(jì)學(xué)意義(P > 0.05);12 h 時(shí)SEP組和DADLE組HMGB1水平與SO組相比均明顯升高(P < 0.05),且DADLE組明顯低于SEP組(P < 0.05);18 h時(shí)SEP組和DADLE組HMGB1水平達(dá)到最高。同樣DADLE組明顯低于SEP組(P < 0.05);24 h時(shí)SEP組和DADLE組HMGB1水平較18 h有所降低,但DADLE組仍明顯低于SEP組(P < 0.05)。
3 討論
本研究采用的大鼠CLP 模型與臨床相關(guān)性較強(qiáng)的膿毒癥模型,血中內(nèi)毒素水平、細(xì)胞因子升高幅度,內(nèi)毒素檢出率及細(xì)菌培養(yǎng)(包括革蘭陽(yáng)性菌和革蘭陰性菌)陽(yáng)性率高、單純的抗炎治療在此模型失敗都與臨床相似[7]。
膿毒癥時(shí)細(xì)菌產(chǎn)生內(nèi)毒素導(dǎo)致大量炎癥因子釋放,包括早期炎癥因子(如TNF-α 和IL-1β)和晚期炎癥因子(如HMGB1)。正是這些炎癥因子,導(dǎo)致組織器官的損傷[8, 9]。然而,一些針對(duì)早期炎癥因子的治療在臨床上并未收到良好的療效,因?yàn)樵缙谘装Y因子在炎癥發(fā)展的早期階段就已經(jīng)開始釋放,并未給拮抗治療留下足夠的時(shí)間窗。況且,在全身炎癥反應(yīng)啟動(dòng)之后再使用 TNF-α和IL-1β的抑制劑也無(wú)法取得明顯的療效[10]。有學(xué)者發(fā)現(xiàn),使用抗HMGB1抗體能明顯減少膿毒癥小鼠的死亡率,即使是在膿毒癥發(fā)生24 h之后仍有明顯的保護(hù)作用[11],這意味著針對(duì)HMGB1的治療策略具有良好的時(shí)間窗,我們以往的研究也發(fā)現(xiàn),DADLE在CLP后4 h給藥仍能對(duì)膿毒癥大鼠起到保護(hù)作用,其機(jī)制可能與抑制晚期炎癥因子HMGB1表達(dá)有關(guān)[12],因此,HMGB1可能是治療膿毒癥的新靶點(diǎn)。本研究中DADLE組肝組織HMGB1水平在12 h,18 h和24 h均明顯低于SEP組,表明DADLE能明顯抑制肝組織HMGB1的表達(dá),減輕急性肝損傷,從而對(duì)膿毒癥大鼠肝損傷起到一定的保護(hù)作用。
[參考文獻(xiàn)]
[1] Angus DC,Linde-Zwirble WT,Lidicker J,et al. Epidemiology of severe sepsis in the United States:analysis of incidence,outcome,and associated costs of care[J]. Crit Care Med,2001,29:1303-1310.
[2] Abraham E,Arcaroli J,Carmody A,et al. HMG-1 as a mediator of acute lung inflammation[J]. J Immunol,2000,165:2950-2954.
[3] 姚詠明,盛志勇. 我國(guó)創(chuàng)傷膿毒癥基礎(chǔ)研究新進(jìn)展[J]. 中華創(chuàng)傷雜志,2003,19:9-12.
[4] 姚詠明,徐珊,盛志勇. 高遷移率族蛋白B1的組織損傷效應(yīng)及其干預(yù)途徑[J]. 中國(guó)醫(yī)學(xué)科學(xué)院學(xué)報(bào),2007,29:459-465.
[5] 唐成武,鮑鷹,朱鳴,等.δ阿片受體激動(dòng)劑對(duì)膿毒癥大鼠肝臟保護(hù)作用的研究[J]. 中華臨床醫(yī)師雜志(電子版),2009,3:1113-1118.
[6] Wichterman KA,Baue AE,Chaudry IH. Sepsis and septic shock-a review of laboratory models and a proposal[J]. J Surg Res,1980,29:189-201.
[7] Aird WC. The role of the endothelium in severe sepsis and multiple organ dysfunction syndrome[J]. Blood,2003,101:3765-3777.
[8] Alleva LM,Budd AC,Clark IA. Systemic release of high mobility group box 1 protein during severe murine influenza[J]. J Immunol,2008,181:1454-1459.
[9] Wang H,Bloom O,Zhang M,et al. HMG-1 as a late mediator of endotoxin lethality in mice[J]. Science,1999,285:248-251.
[10] Hunter P. Sepsis under siege:a new understanding of sepsis might lead to the development of therapies to treat septic shock[J]. EMBO Rep,2006,7:667-669.
[11] Fink MP. Bench-to-bedside review:high-mobility group box 1 and critical illness[J]. Crit Care,2007,11:229.
[12] Tang CW,F(xiàn)eng WM,Du HM,et al. Delayed administration of D-Ala2-D-Leu5-enkephalin, a delta-opioid receptor agonist, improves survival in a rat model of sepsis[J]. Tohoku J Exp Med,2011,224:69-76.
(收稿日期:2011-08-01)