徐勝,鄧文宏,孫榮澤,郭聞一,王衛(wèi)星△
不同劑量Apocynin對重癥急性胰腺炎模型大鼠腸組織的保護(hù)作用
徐勝1△,鄧文宏2,孫榮澤2,郭聞一2,王衛(wèi)星2△
目的 探討還原型輔酶Ⅱ氧化酶(NOX)抑制劑apocynin對重癥急性胰腺炎(SAP)模型大鼠腸道損傷的保護(hù)作用及劑量關(guān)系。方法53只SPF級Wistar大鼠隨機(jī)分為假手術(shù)組(SO組,10只)、SAP模型組(SAP組,12只)、apocynin低劑量組(25 mg/kg,11只)、中劑量組(50 mg/kg,10只)、高劑量組(100 mg/kg,10只)。膽胰管逆行注射5%?;悄懰徕c溶液制備SAP模型,造模前30 min,各劑量組注射apocynin干預(yù)。造模后12 h記錄大鼠存活情況,測定各組腹水量、血清淀粉酶(AMY)、丙氨酸轉(zhuǎn)氨酶(ALT)和肌酐(Cr)水平,并取胰腺、回腸組織行HE染色,進(jìn)行組織病理學(xué)分析。結(jié)果SAP組死亡2只,apocynin低劑量組死亡1只。SAP組大鼠腹水量、AMY、ALT、Cr水平、胰腺病理評分、回腸病理分級均較SO組明顯升高(P<0.05)。低劑量組Cr、腸病理分級較SAP組降低,其他指標(biāo)與SAP組比較差異無統(tǒng)計學(xué)意義。中、高劑量組腹水量、AMY、Cr、胰腺病理評分、腸病理分級均較SAP組降低(P<0.05)。高劑量組ALT、Cr水平較中劑量組升高(P<0.05)。結(jié)論Apocynin可改善SAP模型大鼠癥狀并減輕腸損傷,這可能與其抑制NOX活性有關(guān),50 mg/kg可能是最佳劑量。
胰腺炎,急性壞死性;夾竹桃麻素;重癥急性胰腺炎;還原型輔酶Ⅱ氧化酶;腹水;腸損傷;劑量效應(yīng)關(guān)系,藥物
重癥急性胰腺炎(severe acute pancreatitis,SAP)是一種常見的危急重癥,易引發(fā)全身炎癥反應(yīng)綜合征,可進(jìn)展為肺、腎、肝和腸道等多器官損傷,病死率高達(dá)40%[1-2]。有觀點認(rèn)為,腸道損傷是SAP時胰腺由原位損傷轉(zhuǎn)向多器官功能障礙的關(guān)鍵因素[3-4]。而氧自由基在SAP腸黏膜屏障損傷過程中起重要作用,還原型輔酶Ⅱ氧化酶(NADPH oxidase,NOX)是血管壁活性氧(ROS)的主要來源[5]。因此,下調(diào)NOX表達(dá)水平是減輕SAP癥狀、控制SAP發(fā)展的關(guān)鍵。4′-羥基-3-甲氧基苯乙酮(香草乙酮,apocynin)是NOX的特異性抑制劑,本研究通過使用不同劑量apocynin作用于SAP模型大鼠,觀察NOX的表達(dá)變化及大鼠胰腺和腸道損傷程度,旨在探索apocynin在SAP中的保護(hù)作用及劑量效應(yīng)關(guān)系。
1.1 材料及分組二甲基亞砜(DMSO)、牛磺膽酸鈉購自Sigma公司,使用前無菌生理鹽水配制,apocynin購自Santa公司,用前以DMSO溶解至所需濃度。SPF級Wistar大鼠53只,體質(zhì)量200~250 g,購自湖北省疾病預(yù)防控制中心,按照隨機(jī)區(qū)組實驗設(shè)計分為假手術(shù)組(SO組,10只)、模型組(SAP組,12只)、apocynin低劑量組(25 mg/kg,11只)、中劑量組(50 mg/kg,10只)、高劑量組(100 mg/kg,10只)。
1.2 模型制備及干預(yù)大鼠術(shù)前禁食12 h,腹腔注射10%水合氯醛(3 mL/kg)麻醉,無菌環(huán)境下上腹正中切口開腹,以頭皮輸液針針頭穿過十二指腸對系膜緣、經(jīng)胰乳頭逆行插入主胰管,沿胰膽管逆行勻速(0.1 mL/min)注射5%?;悄懰徕c溶液(1 mL/kg)造模。注射結(jié)束5 min后確認(rèn)沿胰管周圍組織出現(xiàn)水腫、出血,提示造模成功;逐層關(guān)腹縫合,術(shù)后皮下補液(生理鹽水2 mL/kg)。造模前30 min,SAP組由股靜脈注射10%DMSO溶液(2 mL/kg),apocynin低、中、高劑量組分別由股靜脈注射相應(yīng)劑量的apocynin。SO組則于造模前30 min股靜脈注射10%DMSO(2 mL/kg)后,麻醉、開腹,翻動大網(wǎng)膜、胰腺后縫合關(guān)腹。
1.3 標(biāo)本采集及檢測術(shù)后觀察12 h,記錄各組大鼠存活情況。處死大鼠,腹部消毒后剖腹,將無菌干棉球放入大鼠腹腔、汲取全部腹水,記錄大鼠腹水量。腹水量測定:以電子分析天平分別記錄干棉球質(zhì)量(干質(zhì)量)及汲取腹水后的質(zhì)量(濕質(zhì)量),計算腹水量(g)=濕質(zhì)量(g)-干質(zhì)量(g)。心臟采血后分離血清,全自動生化分析測定血清淀粉酶(AMY)、血肌酐(Cr)及丙氨酸轉(zhuǎn)氨酶(ALT)水平。取部分胰頭部組織、回腸組織用于病理分析。
1.4 組織病理學(xué)分析胰腺組織用10%福爾馬林固定24 h,石蠟包埋切片,HE染色。根據(jù)Schmidt等[6]的方法,按胰腺組織水腫(0~4分)、胰腺腺泡壞死(0~2分)、出血和脂肪壞死(0~4分)、炎癥和血管周圍炎性浸潤(0~4分)4方面進(jìn)行詳細(xì)病理評分。參照Chiu等[7]研究,將小腸黏膜損傷分為6級:0級,正常黏膜絨毛結(jié)構(gòu);1級,腸黏膜絨毛頂端上皮下間隙增寬;2級,絨毛上皮下間隙進(jìn)一步擴(kuò)大,絨毛頂端上皮抬高與固有膜剝離;3級,絨毛兩邊上皮成塊脫落;4級,絨毛上皮完全脫落;5級,黏膜固有膜崩解,出現(xiàn)出血和潰瘍。
1.5 統(tǒng)計學(xué)方法采用SPSS 13.0統(tǒng)計軟件進(jìn)行數(shù)據(jù)分析處理,符合正態(tài)分布的計量資料以均數(shù)±標(biāo)準(zhǔn)差表示,多組間均數(shù)比較單因素方差分析,組間多重比較采用LSD-t法,以P<0.05為差異有統(tǒng)計學(xué)意義。
Tab.1 Comparison of the contents of AMY,Cr,ALT and histological scores between five groups表1 各組大鼠AMY、Cr和ALT含量及病理評分比較結(jié)果(n=10,)
Tab.1 Comparison of the contents of AMY,Cr,ALT and histological scores between five groups表1 各組大鼠AMY、Cr和ALT含量及病理評分比較結(jié)果(n=10,)
**P<0.01;a與SO組比較,b與SAP組比較,c與低劑量組比較,d與中劑量組比較,P<0.05
AMY(U/L)1 236.00±155.72 4 918.20±389.63a4 280.50±271.81 3 698.00±386.93abc3 561.80±393.16b175.504**組別SO組SAP組低劑量組中劑量組高劑量組F腹水量(g)0.16±0.02 7.75±1.06a6.15±0.85 4.53±0.72abc5.12±0.61b147.641**Cr(μmol/L)35.87±5.21 80.25±10.87a47.76±7.23b46.21±6.86ab58.69±7.31bd47.744**ALT(U/L)112.38±10.58 283.26±30.58a269.13±24.49 242.77±27.78ab331.82±39.36d85.486**胰腺病理評分(分)0.05±0.16 7.10±0.56a6.95±0.50 5.30±0.42abc5.20±0.42bc344.944**回腸病理評級(級)0.10±0.32 3.60±0.52a3.00±0.47b2.20±0.42abc2.10±0.32bc101.250**
2.1 動物存活情況SAP組死亡2只,apocynin低劑量組死亡1只,其余3組均無死亡。
2.2 腹水量變化SAP組腹水量較SO組顯著增加(P<0.05),低劑量組與SAP組比較差異無統(tǒng)計學(xué)意義;中、高劑量組腹水量差異無統(tǒng)計學(xué)意義,但均少于SAP組(P<0.05),見表1。
2.3 AMY、Cr、ALT水平變化SAP組較SO組AMY、Cr、ALT水平均明顯升高(P<0.05),低劑量組與SAP組相比僅出現(xiàn)Cr水平降低,AMY、ALT水平無明顯變化;而中劑量組較SAP組AMY、Cr水平均明顯降低。高劑量組Cr、ALT水平較中劑量組升高(P<0.05),AMY水平與中劑量組差異無統(tǒng)計學(xué)意義,見表1。
2.4 胰腺組織病理學(xué)改變SO組胰腺結(jié)構(gòu)基本正常,無明顯水腫、出血及炎癥細(xì)胞浸潤;SAP組胰腺正常結(jié)構(gòu)被破壞,腺泡水腫、出血、壞死明顯,大量炎癥細(xì)胞浸潤,病理評分較SO組顯著增高(P<0.05);低劑量組病理評分與SAP組差異無統(tǒng)計學(xué)意義;中、高劑量組胰腺腺泡壞死、出血、炎癥細(xì)胞浸潤,病理評分較SAP組均降低(P<0.05),而中、高劑量組之間病理評分無明顯差異,見表1、圖1。
2.5 回腸組織病理學(xué)改變SO組回腸顯微結(jié)構(gòu)基本正常,黏膜結(jié)構(gòu)完整,無明顯缺損、剝離;SAP組鏡下見回腸組織絨毛結(jié)構(gòu)受損,部分區(qū)域可見絨毛與固有膜剝離、上皮破潰脫落,病理評級較SO組明顯增加;低劑量組病理評級較SAP組降低(P<0.05);中劑量組腸黏膜絨毛部分脫落,與固有層存在間隙,病理評級較SAP組及低劑量組降低(P<0.05),但與高劑量組差異無統(tǒng)計學(xué)意義,見表1、圖2。
Fig.1 Comparison of pathological sections of pancreas between three groups of rats(HE,×200)圖1 3組大鼠胰腺病理切片對比(HE,×200)
Fig.2 Comparison of histological sections of intestinal tissues between three groups(HE,,×400)圖2 3組大鼠回腸組織病理切片比較(HE,×400)
腸道損傷是SAP發(fā)展為多器官功能障礙綜合征(MODS)的重要因素之一,SAP發(fā)病初期往往合并麻痹性腸梗阻和(或)胃腸功能障礙[2]。研究顯示,腸黏膜酸中毒、ROS、細(xì)胞因子和炎癥介質(zhì)、中性粒細(xì)胞黏附等可導(dǎo)致腸黏膜細(xì)胞凋亡增加,絨毛結(jié)構(gòu)喪失,微循環(huán)障礙加重,引起腸道功能障礙[8-11]。
NOX作為人體廣泛分布的酶類,近幾年被證實在心臟氧化應(yīng)激[12]、肝臟與腦缺血再灌注損傷[13-14]、膿毒癥[15]、急性呼吸窘迫綜合征[16]等炎癥反應(yīng)中發(fā)揮重要的作用,在控制炎癥方面具廣泛應(yīng)用前景。炎癥反應(yīng)時,NOX家族發(fā)生“氧化爆發(fā)”,產(chǎn)生大量ROS,參與信號轉(zhuǎn)導(dǎo)、免疫功能、激素生物合成,構(gòu)成機(jī)體抵抗病原體的第一防線[17-18]。Yu等[19-21]用蛙皮素誘導(dǎo)胰腺炎腺泡細(xì)胞AR42J后發(fā)現(xiàn),NOX可介導(dǎo)激活核因子(NF)-κB炎癥通路及白細(xì)胞介素(IL)-6表達(dá),同時通過上調(diào)凋亡誘導(dǎo)因子表達(dá),參與細(xì)胞的凋亡過程,而NOX抑制劑二苯基碘(DPI)可有效抑制其凋亡。Gukovskaya等[22]發(fā)現(xiàn)NOX可介導(dǎo)胰腺炎小鼠胰腺內(nèi)蛋白酶的激活過程。而腸損傷作為SAP發(fā)展、導(dǎo)致全身損傷的始動步驟,NOX是否也通過上述相似機(jī)制,參與SAP腸黏膜屏障損傷,進(jìn)而加重SAP造成的整體損傷程度,反之,通過抑制NOX活性水平,能否降低SAP造成腸道及整體損傷水平,尚鮮有研究報道。
Apocynin是NOX特異性抑制劑,具有特異性強、作用效價高的特點,目前已成為治療腹腔尤其是腸道急性炎癥的新方向[17,23-25]。Mouzaoui等[23]研究顯示apocynin可抑制NOX活性,減少氧自由基生成及降低相關(guān)炎癥通路激活水平,減輕急性腹腔炎癥模型小鼠的腸損傷及整體炎癥水平。Rima等[24]發(fā)現(xiàn)apocynin可使急性、慢性結(jié)腸炎小鼠結(jié)腸上皮細(xì)胞活性增加、減少氧自由基和腫瘤壞死因子(TNF)-α的生成。Cagin等[25]研究顯示apocynin可抑制NADPH氧化酶活性,減少氧化應(yīng)激和細(xì)胞凋亡,防止氧自由基的形成,對大鼠放射性結(jié)腸損傷具有保護(hù)作用[25]。本研究顯示,apocynin可減輕SAP模型大鼠腸道及胰腺損傷,主要表現(xiàn)為腹水量減少,AMY、Cr水平降低,胰腺、回腸病理評分降低。因此,筆者推測apocynin可能通過抑制NOX活性,降低胰酶表達(dá),下調(diào)ROS生成及炎癥通路激活水平,從而減少胰腺腺泡細(xì)胞破壞,起到保護(hù)胰腺的作用。值得注意的是,高劑量組較中劑量組的Cr、ALT水平有所升高,提示大劑量apocynin可能造成肝、腎功能損傷,這可能與SAP環(huán)境下過量給予apocynin增加肝腎代謝負(fù)擔(dān)有關(guān),具體機(jī)制尚待進(jìn)一步研究。
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(2016-08-24收稿 2016-11-07修回)
(本文編輯 胡小寧)
The protective effects of different doses of apocynin on intestines of rats with severe acute pancreatitis
XU Sheng1△,DENG Wenhong2,SUN Rongze2,GUO Wenyi2,WANG Weixing2△
1 Department of Gastrointestinal Surgery,People’s Hospital of Guangxi Zhuang Automomous Region,Nanning 530021,China; 2 Department of General Surgery,Renmin Hospital,Wuhan University△
ObjectiveTo investigate the optimal dose of apocynin to protect severe acute pancreatitis(SAP)and SAP caused intestinal injury in rats.MethodsA total of 53 SPF male Wistar rats were randomly allocated into five groups:sham operation group(SO group,n=10),SAP group(n=12),low-dose apocynin group(25 mg/kg,n=11),medium-dose apocynin group(50 mg/kg,n=10)and high-dose apocynin group(100 mg/kg,n=10).SAP model was prepared by retrograde infusing 5%sodium taurocholate (1 mL/kg)into biliopancreatic duct of rat.At thirty minutes before modeling,apocynin was injected into rat to intervention.The survival condition was recorded at 12 h after modeling,and blood samples were obtained for detecting serum amylase(AMY), alanine aminotransferase(ALT)and creatinine(Cr).Pancreatic and ileal tissue samples were obtained for HE staining and pathological examination.ResultsTwo rats died in SAP group and one died in low-dose apocynin group.The quantity of ascites, the levels of AMY,ALT,Cr and pancreatic and intestinal pathologic scores were significantly increased in SAP group than those in SO group(P<0.05).Except the levels of Cr and intestinal pathologic score,there was no significant difference between lowdose apocynin group and SAP group.The quantity of ascites ascites,levels of AMY,Cr and pancreatic and intestinal pathologic scores were significantly lower in medium-dose and high-dose apocynin groups than those in SAP group(P<0.05).The levels of ALT and Cr were significantly higher in high-dose apocynin group than those of medium-dose apocynin group(P<0.05).ConclusionApocynin improves SAP symptoms and reduces SAP caused intestinal injury in rats,which may be related to the inhibition of NOX activity,and 50 mg/kg of apocynin is the optimal dose.
pancreatitis,acute necrotizing;apocynin;severe acute pancreatitis;NOX;ascites;intestinal injury;doseresponse relationship,drug
R576
A
10.11958/20160895
國家自然科學(xué)基金項目資助(81360081);武漢大學(xué)自主科研項目(2042015kf0090)
1廣西南寧,廣西壯族自治區(qū)人民醫(yī)院胃腸外科(郵編530021);2武漢大學(xué)人民醫(yī)院普外科
徐勝(1980),男,副主任醫(yī)師、博士,主要從事胃腸胰外科與腔鏡微創(chuàng)的基礎(chǔ)與臨床研究
△通訊作者徐勝E-mail:xvsheng@hotmail.com;王衛(wèi)星E-mail:sate.llite@163.com