梁 凱， 孔維宗， 陳 娟， 王迎春

(1 大連大學(xué)，遼寧 大連 116001；2 大連大學(xué)附屬中山醫(yī)院 消化二科， 遼寧 大連 116001)

腸三葉因子對非酒精性脂肪性肝炎大鼠回腸黏液屏障的影響

梁 凱1， 孔維宗2， 陳 娟2， 王迎春2

(1 大連大學(xué)，遼寧 大連 116001；2 大連大學(xué)附屬中山醫(yī)院 消化二科， 遼寧 大連 116001)

目的 研究非酒精性脂肪性肝炎(NASH)大鼠腸道黏液屏障改變，探討腸三葉因子(TFF3)對NASH大鼠腸道黏液屏障的影響，及其對NASH的治療作用。方法 將清潔級雄性SD 大鼠60只隨機(jī)分為正常組、模型組和治療組，每組20只。正常組給予普通飼料，模型組和治療組給予高脂飼料12周，誘導(dǎo)NASH模型后，治療組給予rhTFF3 1 ml·kg-1·d-1(濃度0.1 mg/ml)腹腔內(nèi)注射，正常組與模型組給予1 ml·kg-1·d-1生理鹽水，連續(xù)3周。第15周末，F(xiàn)ITC標(biāo)記的右旋糖酐灌胃檢測大鼠回腸通透性后，處死大鼠，檢測血清AST、ALT、TC、TG、內(nèi)毒素(ET)水平及二胺氧化酶(DAO)活性。HE染色觀察肝臟和回腸末端組織病理變化，PAS染色觀察回腸末端杯狀細(xì)胞并計數(shù)，免疫組化方法檢測回腸末端緊密連接蛋白Occludin和TFF3 蛋白表達(dá)水平，實(shí)時熒光定量PCR檢測TFF3 mRNA轉(zhuǎn)錄水平。計量資料多組間比較采用單因素方差分析，進(jìn)一步兩兩比較采用LSD-t檢驗。結(jié)果 大鼠血清 AST、ALT、TG、TC、DAO、ET水平在模型組升高，而治療組較模型組明顯下降(P值均<0.01)；模型組NAS評分較正常組顯著增高(P<0.01)，而治療組肝組織炎癥改善，NAS評分較模型組明顯降低(P<0.01)；光鏡下模型組回腸末端細(xì)胞壞死，絨毛損傷，杯狀細(xì)胞明顯減少，治療組絨毛損傷修復(fù)，杯狀細(xì)胞增多；模型組大鼠回腸通透性與正常組比顯著增加，治療組較模型組明顯降低(P值均<0.01)；Occludin和TFF3在模型組表達(dá)減少，而治療組較模型組增多(P值均<0.01)；回腸末端TFF3 mRNA轉(zhuǎn)錄水平模型組較正常組下調(diào)，治療組表達(dá)較模型組上調(diào)(P值均<0.01)。結(jié)論 NASH大鼠存在腸道杯狀細(xì)胞損傷，黏液屏障功能障礙，TFF3可以修復(fù)回腸末端損傷，促進(jìn)杯狀細(xì)胞再生與黏液分泌，修復(fù)腸屏障功能，降低腸通透性，對NASH起到治療作用。

脂肪肝； 腸三葉因子； 杯狀細(xì)胞； 大鼠, Sprague-Dawley

非酒精性脂肪性肝病(NAFLD)是一種與遺傳易感和胰島素抵抗密切相關(guān)的代謝性疾病[1]，非酒精性脂肪性肝炎(NASH)在NAFLD的病程中占有重要地位。近來研究[2]發(fā)現(xiàn) NASH與腸道屏障功能異常有關(guān)。腸三葉因子(trefoil factor 3, TFF3)是一個重要的黏膜保護(hù)因子，主要由腸道黏膜杯狀細(xì)胞合成并分泌，形成腸黏膜緩沖帶，保護(hù)腸道上皮細(xì)胞。其還有促進(jìn)黏膜細(xì)胞遷移、分化，加速損傷修復(fù)，調(diào)節(jié)炎癥與免疫反應(yīng)等作用[3-6]。關(guān)于TFF3對NASH作用的研究鮮有報道，本實(shí)驗通過給予NASH模型大鼠人重組TFF3(rhTFF3)處理，探討 TFF3對NASH大鼠回腸末端黏液屏障的影響及對NASH的治療作用。

1 材料與方法

1.1 材料 清潔級雄性SD大鼠，4周齡，體質(zhì)量(200±20)g，購自大連醫(yī)科大學(xué)動物研究中心。高脂飼料(88%普通飼料+10%豬油+2%膽固醇)，定制于北京華阜康生物科技股份有限公司。鱟試劑盒購自上海伊華生物技術(shù)有限公司，二胺氧化酶(DAO)試劑盒由南京建成生物工程研究所提供，rhTFF3購自PrimeGene公司，兔抗TFF3多克隆抗體購自美國Abnova公司，兔抗Occludin單克隆抗體購自香港Abcam有限公司，RNA提取試劑盒、逆轉(zhuǎn)錄酶試劑盒、實(shí)時熒光定量PCR試劑盒購自大連寶生物公司。

1.2 實(shí)驗方法

1.2.1 實(shí)驗動物分組及處理 清潔級SD 大鼠60只，飼養(yǎng)1周后，隨機(jī)分為正常組、模型組和治療組，每組20只。采用徐正婕等[7]造模方法，正常組給予普通飼料，模型組及治療組給予高脂飼料。飼養(yǎng)12周后，每組處死2只大鼠驗證NASH模型，治療組給予rhTFF3 1 ml·kg-1·d-1(濃度為0.1 mg/ml) 腹腔注射[8-9]，正常組與模型組給予1 ml·kg-1·d-1生理鹽水，連續(xù)3周。第15周末，用10%水合氯醛按2 ml/kg腹腔內(nèi)注射麻醉大鼠。門靜脈取血保存后，處死大鼠取出肝臟，吸干后稱重，計算肝指數(shù)(肝指數(shù)=肝質(zhì)量/體質(zhì)量×100%)。取部分肝組織及末端回腸組織以中性甲醛固定，部分末端回腸組織用液氮處理，置于-80 ℃保存。

1.2.2 回腸通透性檢測 15周末，采用Kwak等[10]的方法，大鼠麻醉前先禁食水4 h后，F(xiàn)ITC標(biāo)記的右旋糖酐4 kD 60 mg/100 g 體質(zhì)量(濃度為100 mg/ml)給大鼠灌胃，4 h后心臟取血0.8～1.2 ml，4 ℃保存。3000 r/min低溫離心15 min后，用Victor3分光光度計(激發(fā)光485、放射光525)檢測血清樣本熒光強(qiáng)度。

1.2.3 血生化指標(biāo)檢測 采用美國強(qiáng)生Vitros 5.1 FS自動生化分析儀測定門靜脈血TG、TC、ALT、AST水平。按說明書采用顯色基質(zhì)鱟試劑盒終點(diǎn)顯色法對門靜脈血中的內(nèi)毒素(ET)進(jìn)行檢測，分光光度法檢測血漿中 DAO活性。

1.2.4 肝組織病理觀察 將甲醛固定、石蠟包埋的肝臟及末端回腸組織樣本，行常規(guī)HE染色，并在光學(xué)顯微鏡下觀察。根據(jù)《非酒精性脂肪性肝病診療指南(2010年修訂版)》[11]NAS積分標(biāo)準(zhǔn)，對肝臟進(jìn)行NAS評分，NAS<3分可排除NASH，NAS>4分則可診斷NASH，介于兩者之間為NASH可能。部分末端回腸樣本行PAS染色，并采用文獻(xiàn)[12]中杯狀細(xì)胞計數(shù)方法，每個樣本切片選取5個視野，統(tǒng)計每100個回腸末端上皮細(xì)胞中PAS陽性細(xì)胞數(shù)。

1.2.5 回腸末端組織免疫組化染色 將甲醛固定好的回腸組織脫水、石蠟包埋，在切片機(jī)上切成4 μm薄片。用兔抗大鼠TFF3(1∶100)、Occludin(1∶100)進(jìn)行免疫組化染色，光學(xué)顯微鏡下觀察，并用Image-Pro Plus 6.0圖像軟件分析。

1.2.6 實(shí)時熒光定量PCR 設(shè)計TFF3引物序列，上游引物：5′-TTCTGGATAACCCTGCTGCT-3′，下游引物：5′-TAGCCACAGTCCACCCTGA-3′。GAPDH上游引物：5′-CCCCCAATGTATCCGTTGTG-3′，下游引物：5′-TAGCCCAGGATGCCCTTTAGT-3′。用Trizol法提取回腸組織總RNA，測定純度，按逆轉(zhuǎn)錄試劑盒說明合成cDNA，然后進(jìn)行實(shí)時熒光定量PCR，以GAPDH為內(nèi)參引物標(biāo)準(zhǔn)化TFF3含量。循環(huán)條件為：95 ℃預(yù)變性2 min，95 ℃變性40 s，45 ℃復(fù)性40 s，60 ℃延伸1 min，35個循環(huán)后60 ℃再延伸7 min。

2 結(jié)果

2.1 回腸通透性變化 3組大鼠回腸通透性比較，差異有統(tǒng)計學(xué)意義(F=614.84，P<0.001)。模型組大鼠血漿中右旋糖酐水平較正常組明顯增高[(120.87±10.71) μg/ml vs (36.04±5.70) μg/ml，P<0.01]，治療組較模型組降低[(47.39±6.25) μg/ml vs (120.87±10.71) μg/ml，P<0.01]。結(jié)果表明模型組大鼠腸通透性增高，而rhTFF3能改善大鼠腸通透性。

2.2 血清生化指標(biāo)檢測結(jié)果 大鼠血清TG、TC、ALT、AST、ET、DAO水平在模型組均較正常組顯著升高(P值均<0.01)；治療組較模型組明顯下降(P值均<0.01)。模型組大鼠比正常組肝指數(shù)明顯增高(P<0.01)，而rhTFF3處理后，大鼠肝指數(shù)較模型組降低(P<0.01)(表1)。

2.3 肝臟病理學(xué)改變及NAS評分 光鏡下見正常組肝小葉結(jié)構(gòu)正常，細(xì)胞呈條索狀排列，無明顯脂肪變性，未見炎性細(xì)胞浸潤；模型組肝細(xì)胞明顯腫大，可見大小不等的脂滴充滿細(xì)胞，發(fā)生脂肪變性，肝小葉內(nèi)局灶性炎癥、細(xì)胞壞死；治療組可見肝細(xì)胞脂肪變，小葉內(nèi)炎性細(xì)胞浸潤，改變較模型組減輕(圖1)。3組大鼠NAS積分比較差異有統(tǒng)計學(xué)意義(F=172.31，P<0.001)，且模型組較正常組顯著增高[(6.97±1.01)分 vs (1.06±0.63)分，P<0.01]，而治療組相比模型組降低[(3.18±1.18)分 vs (6.97±1.01)分，P<0.01]。

圖1 3組大鼠肝組織HE染色結(jié)果(×200) a：正常組；b：模型組；c：治療組

2.4 回腸末端病理改變及杯狀細(xì)胞計數(shù) 正常組回腸末端表面絨毛豐富，排列整齊，黏膜完整連續(xù)，未見炎性細(xì)胞浸潤，杯狀細(xì)胞位于腸腺上皮與黏膜上皮之間，如酒杯狀，數(shù)量豐富。模型組回腸絨毛疏松紊亂、萎縮、變鈍，黏膜可見水腫、炎性細(xì)胞浸潤，杯狀細(xì)胞稀疏，萎縮甚至消失。與模型組比較，治療組黏膜絨毛較豐富，黏膜水腫、炎性細(xì)胞浸潤等改變較模型組輕，杯狀細(xì)胞排列較整齊，數(shù)量較多(圖2)。PAS染色結(jié)果示，陽性杯狀細(xì)胞顯色為深紫色，分布于黏膜上皮及腸腺上皮之間(圖3)，3組大鼠回腸黏膜杯狀細(xì)胞計數(shù)差異有統(tǒng)計學(xué)意義(F=109.31,P<0.001)，模型組杯狀細(xì)胞數(shù)量較正常組明顯減少[(22.53±2.67)個vs (35.10±3.21)個，P<0.01]，而治療組與模型組相比明顯增多[(27.80±1.50)個 vs (22.53±2.67)個，P<0.01]。

表1 3組大鼠各項血清學(xué)指標(biāo)和肝指數(shù)檢測結(jié)果比較

注：與正常組比較，1)P<0.01；與模型組比較，2)P<0.01

圖2 3組大鼠回腸末端組織HE染色(×100) a：正常組；b：模型組；c：治療組

圖3 3組大鼠回腸末端組織PAS染色 (×100) a：正常組；b：模型組；c：治療組

2.5 免疫組化染色觀察大鼠回腸末端Occludin及TFF3表達(dá) Occludin分布于回腸上皮細(xì)胞連接處，3組大鼠緊密連接蛋白Occludin表達(dá)差異有統(tǒng)計學(xué)意義(F=255.86，P<0.001)。正常組呈強(qiáng)表達(dá)，模型組較正常組表達(dá)減弱(12.47±2.16 vs 35.64±4.21，P<0.01)；而治療組較模型組表達(dá)增強(qiáng)(16.95±3.08 vs 12.47±2.16，P<0.01)(圖4)。從腸隱窩基底部到腸腔表面都可見TFF3陽性染色，3組大鼠TFF3表達(dá)差異有統(tǒng)計學(xué)意義(F=353.66，P<0.001)； 正常組回腸中TFF3主要見于黏膜杯狀細(xì)胞胞漿和黏膜表面黏液層，表達(dá)較強(qiáng)；模型組黏液層稀薄，TFF3表達(dá)較正常組明顯減弱(23.72±4.01 vs 52.60±2.48，P<0.01)；與模型組相比，治療組信號增多，表達(dá)增強(qiáng)(30.22±3.58 vs 23.72±4.01，P<0.01)(圖5)。

圖4 3組大鼠回腸黏膜緊密連接蛋白Occludin的表達(dá)(×200) a：正常組；b：模型組；c：治療組

圖5 3組大鼠回腸黏膜TFF3的表達(dá)(×200) a：正常組；b：模型組；c：治療組

2.6 大鼠回腸TFF3 mRNA表達(dá)變化 3組大鼠TFF3 mRNA表達(dá)差異有統(tǒng)計學(xué)意義(F=142.50，P<0.001)。與正常組比較，模型組表達(dá)明顯下調(diào)(0.43±0.15 vs 1.03±0.21，P<0.01)，而治療組表達(dá)較模型組上調(diào)(0.75±0.10 vs 0.43±0.15，P<0.01)。

3 討論

腸道內(nèi)含有萬億計的數(shù)千種微生物及其產(chǎn)物，還有來自上消化道的各種消化酶、膽汁、酸，以及食物中難消化的纖維素、化合物等，這些構(gòu)成了腸內(nèi)復(fù)雜的環(huán)境[13]。因此，腸道成為細(xì)菌及各種毒素入侵機(jī)體的重要門戶，腸道屏障在抵御腸腔內(nèi)各種損傷，保護(hù)機(jī)體方面發(fā)揮重要作用。而近來研究[14-15]發(fā)現(xiàn)NAFLD的發(fā)生發(fā)展與腸道屏障功能損傷密切相關(guān) 。

本研究結(jié)果顯示，模型組血清 AST、ALT、TG、TC、DAO、ET水平較正常組明顯升高。其中 DAO常用來反映腸道機(jī)械屏障完整性及黏膜絨毛損傷程度，DAO水平升高提示存在腸上皮損傷。另外，腸通透性常用于評估腸道屏障功能，模型組大鼠腸通透性較正常組明顯增加，表明 NASH大鼠存在腸道黏膜損傷，導(dǎo)致腸道屏障功能障礙，腸通透性增加。并且Occludin作為重要的回腸上皮細(xì)胞間緊密連接蛋白之一，在模型組表達(dá)明顯下調(diào)，也提示腸道屏障功能損傷，這都將使血清ET水平升高。而ET隨血進(jìn)入肝臟，刺激炎癥因子及生物活性物質(zhì)釋放，進(jìn)而導(dǎo)致肝臟炎癥與壞死[16]。Miele等[17]研究也發(fā)現(xiàn)NAFLD患者腸通透性較健康者明顯增加，存在明顯的小腸菌群過度生長。Friedman[18]認(rèn)為NAFLD后的腸黏膜屏障損傷，腸通透性增加，導(dǎo)致腸內(nèi)細(xì)菌及毒素入侵機(jī)體，誘導(dǎo)炎性反應(yīng)，促進(jìn)炎性因子和炎性細(xì)胞在肝臟蓄積，這成為NASH發(fā)生的重要因素。因此，腸屏障功能異常及通透性增加與NASH密切相關(guān)[19]。

近來研究發(fā)現(xiàn)TFF3是一個重要的黏膜保護(hù)因子。許多疾病狀態(tài)下，腸黏膜損傷，TFF3表達(dá)異常。Hensel等[20]研究兒科炎癥性腸病患者，發(fā)現(xiàn)伴有炎癥的患兒其腸黏膜組織TFF3和MUC2表達(dá)顯著降低，而無炎癥的患兒其表達(dá)較健康者水平高。Renes等[21]也發(fā)現(xiàn)，在葡聚糖硫酸鈉誘導(dǎo)的腸損傷模型上，腸道急性炎性反應(yīng)和緩解再生階段，杯狀細(xì)胞表達(dá) TFF3 mRNA和蛋白明顯增多。本研究中NASH大鼠存在明顯回腸損傷及炎癥，可能是由于TFF3表達(dá)異常。TFF3主要由腸道上皮杯狀細(xì)胞合成并分泌[2]，而PAS染色結(jié)果顯示模型組回腸杯狀細(xì)胞稀疏，萎縮甚至消失，數(shù)量較正常組明顯減少。NASH大鼠回腸杯狀細(xì)胞受損，數(shù)量減少，進(jìn)而合成分泌的TFF3減少。免疫組化染色結(jié)果也顯示NASH大鼠TFF3表達(dá)減少，回腸黏液層稀薄。

TFF3保護(hù)腸道有多種機(jī)制。其與MUC2共同組成腸上皮黏液層，形成一層保護(hù)膜，將腸上皮與腸內(nèi)環(huán)境隔離，成為腸內(nèi)第一道保護(hù)屏障[22]，有效的阻止了消化酶、機(jī)械應(yīng)力、酸、腸微生物等對組織損傷。黏液層可分為內(nèi)外兩層：內(nèi)層比較致密，含細(xì)菌少，主要起到保護(hù)作用。有研究[23]提出，黏液層只能透過2 μm物質(zhì)，因而較大物質(zhì)被阻擋在腸腔內(nèi)，較小的營養(yǎng)分子則可透過黏液層被上皮細(xì)胞吸收。另外在內(nèi)層黏液中，混有潘氏細(xì)胞分泌的抗菌肽和抗菌素，能抑制細(xì)菌在黏液內(nèi)層定植與生長[24]。外層黏液較稀薄，界限不清，是腸道菌群生長的理想場所，因此定居著大量的正常菌群[25]。它們在抑制腸內(nèi)有害細(xì)菌的定植與生長和調(diào)節(jié)腸內(nèi)生物屏障方面發(fā)揮重要作用。研究[26]發(fā)現(xiàn)，在燒傷刺激作用下，杯狀細(xì)胞結(jié)構(gòu)受損，數(shù)量減少，黏液分泌明顯減少。另外，腸道上皮的慢性炎癥反應(yīng)也出現(xiàn)杯狀細(xì)胞減少，MUC2和TFF3分泌減少，有害細(xì)菌易穿透黏液層定植在腸上皮而導(dǎo)致黏膜細(xì)胞損傷[27]。而在TFF3基因缺陷的小鼠中，發(fā)現(xiàn)腸道黏液層稀薄、通透性增高，對腸道損傷敏感性增強(qiáng)，其死亡率也明顯升高[28-29]。通過補(bǔ)充TFF3，能明顯改善TFF3缺陷導(dǎo)致的腸道損傷，而作為腸道屏障功能密切相關(guān)的緊密連接蛋白claudin-1和ZO-1，有研究[30]發(fā)現(xiàn)TFF3能促進(jìn)其表達(dá)，調(diào)節(jié)腸屏障功能，進(jìn)而改善血小板活化因子誘導(dǎo)的腸黏膜通透性改變。

本實(shí)驗給予NASH大鼠rhTFF3處理后，回腸末端病理改變明顯減輕，緊密連接蛋白Occludin表達(dá)明顯增多，腸通透性改善，血清ET水平降低。另外黏膜杯狀細(xì)胞增多，回腸末端組織TFF3 mRNA表達(dá)較模型組明顯上調(diào)。表明TFF3能促進(jìn)回腸黏膜損傷修復(fù)及杯狀細(xì)胞增生，杯狀細(xì)胞合成分泌功能增強(qiáng)，進(jìn)而改善腸道屏障功能，降低腸通透性，減少ET入血。而治療組大鼠血清 AST、ALT、TG、TC水平較模型組明顯下降，肝組織脂肪變性及炎癥減輕，NAS評分明顯降低，提示TFF3可以改善NASH大鼠肝臟損傷，對NASH起到了治療作用。但是，TFF3具體作用機(jī)制還不清楚，其對肝臟的直接影響也有待進(jìn)一步研究。

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引證本文：LIANG K, KONG WZ, CHEN J, et al. Effect of trefoil factor 3 on intestinal mucous barrier in rats with nonalcoholic steatohepatitis[J]. J Clin Hepatol, 2017, 33(8): 1552-1557. (in Chinese) 梁凱， 孔維宗， 陳娟， 等. 腸三葉因子對非酒精性脂肪性肝炎大鼠回腸黏液屏障的影響[J]. 臨床肝膽病雜志, 2017, 33(8): 1552-1557.

(本文編輯：葛 俊)

Effect of trefoil factor 3 on intestinal mucous barrier in rats with nonalcoholic steatohepatitis

LIANGKai,KONGWeizong,CHENJuan,etal.

(DalianUniversity,Dalian,Liaoning116001,China)

Objective To investigate the change in intestinal mucous barrier in rats with nonalcoholic steatohepatitis (NASH), the effect of trefoil factor 3 (TFF3) on intestinal mucous barrier in NASH rats, and the therapeutic effect of TFF3 on NASH. Methods A total of 60 clean male Sprague-Dawley rats were randomly divided into normal group, model group, and treatment group, with 20 rats in each group. The rats in the normal group were given normal diet, and those in the model group and the treatment group were given high-fat diet to induce NASH. The rats in the treatment group were given intraperitoneal injection of rhTFF3 at a dose of 1 ml·kg-1·d-1(a concentration of 0.1 mg/ml), and those in the normal group and the model group were given normal saline at a dose of 1 ml·kg-1·d-1; the course of treatment was 3 weeks for all groups. At the end of week 15, fluorescein isothiocyanate-labeled dextran was given by gavage to evaluate intestinal permeability, and after the rats were sacrificed, serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (TC), triglyceride (TG), and endotoxin (ET) and diamine oxidase (DAO) activity were measured. HE staining was performed to observe the histopathological changes of the liver and the terminal ileum, PAS staining was performed to observe and count the goblet cells of the terminal ileum, immunohistochemistry was used to measure the expression of the tight junction protein Occludin and TFF3 in the terminal ileum, and quantitative real-time PCR was used to measure the mRNA transcription level of TFF3. A one-way analysis of variance was used for comparison between multiple groups, and the least significant differencet-test was used for further comparison between any two groups. Results The model group had significant increases in serum levels of AST, ALT, TC, TG, and ET and DAO activity, and the treatment group had significant reductions compared with the model group (allP<0.01). The model group had a significant increase in NAFLD activity score compared with the normal group (P<0.01), and the treatment group had significant improvement in liver inflammation and a significant reduction in NAFLD activity score compared with the model group (P<0.01). The model group had cell necrosis, damage of the intestinal villi, and a significant reduction in goblet cells in the terminal ileum under a light microscope; in the treatment group, damage of the intestinal villi was repaired and there was an increase in goblet cells. The model group had a significant increase in intestinal permeability compared with the normal group, and the treatment group had a significant reduction compared with the model group (bothP<0.01). The model group had a significant reduction in the expression of Occludin and TFF3, and the treatment group had a significant increase compared with the model group (allP<0.01). The model group had a downregulated TFF3 mRNA transcription level in the terminal ileum compared with the normal group, and the treatment group had an upregulated level compared with the model group (bothP<0.01). Conclusion NASH rats have damaged goblet cells and mucous barrier dysfunction. TFF3 can repair the damaged terminal ileum, promote the regeneration of goblet cells and mucus secretion, restore intestinal barrier function, reduce intestinal permeability, and thus exert its therapeutic effect on NASH.

fatty liver； trefoil factor 3； goblet cells； rats, Sprague-Dawley

10.3969/j.issn.1001-5256.2017.08.029

2017-02-22；

2017-03-26。

梁凱(1990-)，男，主要從事非酒精性脂肪性肝病研究。

王迎春，電子信箱：wych_1648@126.com。

R575.5

A

1001-5256(2017)08-1552-06