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目的:研究卫矛茎皮醇提取物(EAT)和卫矛翅翘醇提取物(EAW)抗四氯化碳诱导小鼠肝纤维化的作用，并初步探讨其可能机制。方法:选取60只C57BL/6小鼠，按随机数字表法随机分成健康对照组、模型组、EAW低剂量组、EAW高剂量组、EAT低剂量组、EAT高剂量组，每组10只。从造模前3 d开始，EAT低、高剂量组和EAW低、高剂量组小鼠分别予EAT和EAW各2.0、8.0 g/kg(含生药量)灌胃，健康对照组和模型组小鼠均给予等体积纯净水灌胃，1次/d，直至开始造模后第30天，共灌胃33次。EAT低、高剂量组和EAW低、高剂量组，以及模型组小鼠均予5%四氯化碳橄榄油溶液8 mL/kg腹腔注射，健康对照组小鼠予等体积0.9%氯化钠溶液腹腔注射，每周注射2次，至开始造模后第30天，共注射9次。检测各组小鼠的肝脏指数和血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素、白细胞介素-6(IL-6)水平。采用苏木精-伊红和Masson染色法观察小鼠肝组织病理学变化并计算胶原容积分数，采用改良组织学炎症活动度(HAI)和Ishak系统评分评估小鼠肝组织的肝脏炎症反应和纤维化程度。采用免疫组织化学染色法检测α-平滑肌肌动蛋白(α-SMA)表达水平，蛋白质印迹法检测α-SMA、基质金属蛋白酶2(MMP2)和胞外信号调节激酶(ERK)1/2的蛋白质表达水平，荧光定量聚合酶链反应检测n MMP2、n ERK1/2的mRNA表达水平。统计学方法采用方差分析、Tukey检验、Dunn检验。n 结果:EAW低、高剂量组和EAT高剂量组小鼠的肝脏指数均低于模型组(0.06±0.01、0.05±0.01、0.05±0.01比0.07±0.01)，差异均有统计学意义(n q＝5.12、7.70、7.11，均n P<0.01)。EAW低、高剂量组和EAT低、高剂量组小鼠血清ALT、AST水平均低于模型组[(601.76±141.38)、(283.35±42.32)、(734.74±116.06)、(391.60±34.33) U/L比(982.45±96.04) U/L，(509.49±152.29)、(345.41±67.39)、(282.30±65.72)、(243.23±45.20) U/L比(766.01±114.49) U/L]，差异均有统计学意义(n qALT ＝9.88、20.81、7.65、17.58，n qAST ＝5.11、12.52、14.92、15.56；均n P<0.001)。EAW和EAT高剂量组小鼠血清总胆红素水平低于模型组[(6.81±0.49)、(7.08±1.78) μmol/L比(12.68±3.28) μmol/L]，差异均有统计学意义(n q＝6.31、6.01，均n P<0.01)。EAW低、高剂量组和EAT低、高剂量组小鼠血清IL-6水平均低于模型组[(29.26±5.42)、(24.28±4.75)、(9.05±1.74)、(8.01±1.24) ng/L比(53.21±10.05) ng/L]，EAT低剂量组IL-6水平低于EAW低剂量组，EAT高剂量组IL-6水平低于EAW高剂量组，差异均有统计学意义(n q＝12.20、14.73、22.48、22.11、10.28、7.96，均n P<0.001)。EAW低、高剂量组和EAT低、高剂量组胶原容积分数均低于模型组[(6.15±1.09)、(2.91±0.76)、(7.07±1.37)和(5.31±0.80)分比(12.36±1.96)分]，EAW高剂量组低于EAW低剂量组和EAT低、高剂量组，差异均有统计学意义(n q＝11.68、17.78、9.94、13.25，6.10、7.84、4.53；均n P<0.05)。EAW和EAT高剂量组的HAI和Ishak系统评分均低于模型组[6.0分(5.5分，7.5分)、7.0分(6.0分，7.5分)比13.0分(12.0分，13.0分)，1.0分(1.0分，2.0分)、2.0分(1.0分，2.0分)比4.0分(3.0分，4.0分)]，差异均有统计学意义(n ZHAI＝3.38、3.23，n Zlshak＝3.22、3.03；均n P<0.05)。免疫组织化学染色结果显示，EAW低剂量组、EAW高剂量组、EAT高剂量组、EAT低剂量组、模型组小鼠肝组织中α-SMA表达水平分别为4.76±0.36、2.75±0.29、3.72±0.34、5.20±0.79、5.98±0.52，蛋白质印迹法检测结果显示，模型组、EAW低剂量组、EAW高剂量组、EAT低剂量组、EAT高剂量组α-SMA蛋白质表达水平分别为0.96±0.11、0.67±0.07、0.22±0.01、0.78±0.08、0.68±0.07，2种检测方法均提示EAW低、高剂量组和EAT高剂量组小鼠肝组织中α-SMA表达水平均低于模型组，EAW高剂量组的α-SMA表达水平均低于EAW低剂量组和EAT低、高剂量组，差异均有统计学意义(n q免疫组织化学＝6.06、15.95、11.18、9.92、12.10、4.79，n q蛋白质印迹法＝7.29、18.34、6.84、11.05、13.97、11.49，均n P<0.05)。EAW低、高剂量组和EAT低、高剂量组，以及模型组小鼠肝组织中MMP2、ERK1/2的蛋白质和mRNA表达水平分别为0.18±0.04、0.16±0.04、0.28±0.02、0.21±0.02、0.84±0.02，0.80±0.02、0.57±0.08、0.83±0.03、0.69±0.02、0.91±0.04，18.74±1.90、10.73±1.24、24.99±1.84、7.19±0.48、24.68±1.18，29.44±4.47、11.96±0.53、24.75±4.04、5.30±0.36、35.76±0.85，EAW低、高剂量组和EAT低、高剂量组小鼠肝组织中MMP2蛋白质表达水平均低于模型组，EAW、EAT高剂量组小鼠肝组织中ERK1/2蛋白质表达水平均低于模型组，EAW高剂量组ERK1/2蛋白质表达水平低于EAT高剂量组，EAW、EAT高剂量组小鼠肝组织中n MMP2和n ERK1/2的mRNA表达水平均低于模型组，EAW高剂量组的n MMP2和n ERK1/2 mRNA表达水平均低于EAW低剂量组，EAT高剂量组n MMP2和n ERK1/2 mRNA表达水平均低于EAT低剂量、EAW高剂量组，差异均有统计学意义(n q＝22.15、22.96、18.87、21.31，13.42、8.53，4.90，18.57、23.29、16.49、21.11，10.66、12.12，23.70、15.38、13.48、16.73，均n P<0.05)。n 结论:EAT和EAW均可减轻四氯化碳诱导的小鼠肝损伤和肝纤维化，可能与抑制ERK1/2、IL-6等表达而影响Ras/ERK-MMP2信号通路有关。“,”Objective:To study the role of ethanol extract of n Euonymus alatus stems (EAT) and ethanol extract of n Euonymus alatus wings (EAW) in anti-hepatic fibrosis induced by carbon tetrachloride in mice, and to explore its preliminary mechanism.n Methods:Sixty C57BL/6 mice were selected and randomly divided into healthy control group, carbon tetrachloride model (CTM) group, EAW low dose (EAW-L) group, EAW high dose (EAW-H) group, EAT low dose (EAT-L) group and EAT high dose (EAT-H) group, with 10 mice in each group. Three days before modeling, the mice of EAT-L, EAT-H, EAW-L and EAW-H group were gavaged with EAT or EAW at 2.0 or 8.0 g/kg, respectively, and the mice of healthy control group and CTM group were gavaged with equal volume of pure water, once a day till the 30th day after modeling (total 33 times). Five percent carbon tetrachloride olive oil solution was intraperitoneally injected at 8 mL/kg to establish liver fibrosis model in CTM, EAT-L, EAT-H, EAW-L and EAW-H groups. The mice in the healthy control group were intraperitoneally injected with equal volume of 0.9% sodium chloride solution, twice per week for 30 days, and a total of 9 times of injection. The liver index, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil) and interleukin-6 (IL-6) were detected. Hematoxylin-eosin and Masson staining were used to observe the pathological changes of mouse liver tissue and calculate the collagen volume fraction. The liver inflammatory response and fibrosis degree were evaluated by histological activity index (HAI) and Ishak system score. The level of α-smooth muscle actin(α-SMA)in liver tissue was both detected by immunohistochemistry and Western blotting. The expression of matrix metalloproteinase 2 (MMP2) and extracellular signal-regulated kinase (ERK) 1/2 at protein and mRNA level was detected by Western blotting and fluorescent quantitative polymerase chain reaction. Analysis of variance, Tukey test and Dunn test were used for statistical analysis.Results:The hepatic indexes of EAW-L, EAW-H and EAT-H groups were lower than that of CTM group(0.06±0.01, 0.05±0.01 and 0.05±0.01 vs. 0.07±0.01), and the differences were statistically significant (n q=5.12, 7.70, 7.11; all n P<0.01). The serum ALT and AST levels of EAW-L, EAW-H, EAT-L and EAT-H groups were lower than those of CTM group((601.76±141.38), (283.35±42.32), (734.74±116.06) and (391.60±34.33) U/L vs.(982.45±96.04) U/L, (509.49±152.29), (345.41±67.39), (282.30±65.72) and(243.23±45.20) U/L vs.(766.01±114.49) U/L), and the differences were statistically significant (n qALT =9.88, 20.81, 7.65, 17.58, n qAST =5.11, 12.52, 14.92, 15.56; all n P<0.001). The serum TBil levels of EAW-H and EAT-H groups were lower than that of CTM group((6.81±0.49) and (7.08±1.78) μmol/L vs.(12.68±3.28) μmol/L), and the differences were statistically significant(n q=6.31, 6.01; both n P<0.01). The serum IL-6 levels of EAW-L, EAW-H, EAT-L and EAT-H groups were lower than that of CTM group((29.26±5.42), (24.28±4.75), (9.05±1.74) and (8.01±1.24) ng/L vs.(53.21±10.05) ng/L); the serum IL-6 level of EAT-L group was lower than that of EAW-L group; the serum IL-6 level of EAT-H group was lower than that of EAW-H group, and the differences were statistically significant(n q=12.20, 14.73, 22.48, 22.11, 10.28, 7.96; all n P <0.001). The collagen volume fractions of EAW-L, EAW-H, EAT-L and EAT-H groups were lower than that of CTM group (6.15±1.09, 2.91±0.76, 7.07±1.37 and 5.31±0.80 vs. 12.36±1.96); the collagen volume fraction of EAW-H group was lower than that of EAW-L, EAT-L and EAT-H groups, and the differences were statistically significant( n q=11.68, 17.78, 9.94, 13.25; 6.10, 7.84, 4.53; all n P <0.05). The HAI and Ishak system scores of EAW-H and EAT-H groups were lower than those of CTM group (6.0 (5.5, 7.5) and 7.0 (6.0, 7.5) vs. 13.0 (12.0, 13.0), 1.0 (1.0, 2.0) and 2.0 (1.0, 2.0) vs. 4.0 (3.0, 4.0)), and the differences were statistically significant( n ZHAI=3.38, 3.23, n Zlshak=3.22, 3.03; all n P<0.05). The result of immunohistochemical analysis showed that the expression levels of α-SMA in the mice liver tissues of EAW-L, EAW-H, EAT-L, EAT-H and CTM groups were 4.76±0.36, 2.75±0.29, 3.72±0.34, 5.20±0.79 and 5.98±0.52, respectively. The result of Western blotting showed that the expression levels of α-SMA in the mice liver tissues of CTM, EAW-L, EAW-H, EAT-L and EAT-H groups were 0.96±0.11, 0.67±0.07, 0.22±0.01, 0.78±0.08 and 0.68±0.07, respectively. Two detection methods both showed that the expression levels of α-SMA of EAW-L, EAW-H and EAT-H groups were lower than that of CTM group; the expression level of α-SMA of EAW-H group was lower than that of EAW-L, EAT-L and EAT-H group, and the differences were statistically significant(n qimmunohistochemical =6.06, 15.95, 11.18, 9.92, 12.10 and 4.79, n qWestern blotting=7.29, 18.34, 6.84, 11.05, 13.97 and 11.49, all n P<0.05). The expression levels of MMP2 and ERK1/2 at protein and mRNA levels in the mice liver tissues of EAW-L, EAW-H, EAT-L, EAT-H and CTM groups were 0.18±0.04, 0.16±0.04, 0.28±0.02, 0.21±0.02 and 0.84±0.02, 0.80±0.02, 0.57±0.08, 0.83±0.03, 0.69±0.02 and 0.91±0.04, 18.74±1.90, 10.73±1.24, 24.99±1.84, 7.19±0.48 and 24.68±1.18, 29.44±4.47, 11.96±0.53, 24.75±4.04, 5.30±0.36 and 35.76±0.85, respectively. The expression levels of MMP2 at protein level in EAW-L, EAW-H, EAT-L and EAT-H groups were lower than that in CTM group; the expression levels of ERK1/2 at protein level in EAW-H and EAT-H groups were lower than that in CTM group; the expression level of ERK1/2 at protein level in EAW-H group was lower than that in EAT-H group; the expression levels ofn MMP2 and n ERK1/2 at mRNA level in EAW-H and EAT-H group were lower than those in CTM group; the expression levels of n MMP2 and n ERK1/2 at mRNA level in EAW-H group were lower than those in EAW-L group; the expression levels of n MMP2 and n ERK1/2 at mRNA level in EAT-H group were lower than those in EAT-L and EAW-H groups, and the differences were statistically significant(n q=22.15, 22.96, 18.87, 21.31; 13.42, 8.53; 4.90; 18.57, 23.29, 16.49, 21.11; 10.66, 12.12; 23.70, 15.38, 13.48, 16.73; all n P<0.05).n Conclusions:Both EAT and EAW can alleviate carbon tetrachloride-induced liver injury and liver fibrosis in mice, which may be related with inhibiting the expression of ERK1/2 and IL-6 and then affecting the Ras/ERK-MMP2 signaling pathway.