转化生长因子β1Ⅱ型受体在大鼠慢性胰腺炎中的表达及氧化苦参碱对其的影响

Treatment with oxymatrine down-regulates TGFβRII expression in chronic pancreatitis in rats

目的:探讨转化生长因子β1Ⅱ型受体(TβRⅡ)在慢性胰腺炎(CP)纤维化病理进程中的作用,研究氧化苦参碱(OM)对胰腺纤维化的作用机制.方法:40只Wistar♂大鼠随机分为4组,即阴性对照组(NC组,n=10),CP模型组(CP组,n=10),OM干预组(OP组,n=10)和OM治疗组(OT组,n=10).NC组隔日给予腹腔注射生理盐水300mg/kg;其他每组均隔日腹腔注射二乙基硫代氨基甲酸盐(DDC)700mg/kg,30d停止.另外OP组于注射DDC同日开始每日腹腔注射OM100mg/kg,OT组于注射DDC1wk后开始每日腹腔注射OM100mg/kg,分别于注射DDC20d、40d后处死动物.胰腺组织行HE染色和Masson胶原染色并进行病理学评分,Western blot检测胰腺组织TβRⅡ的表达.结果:Masson染色测定结果显示,在20d、40d时CP组胶原纤维含量显著高于其余各组(20d:22.54%±4.45%vs13.16%±1.84%,19.58%±2.78%,2.45±0.24%;40d:35.14%±3.27%vs25.14%±3.67%,28.68%±2.55%,3.0%±0.32%;均P<0.05),OP组和OT组在40d时的胶原纤维面积百分比均比同组20d时增高(25.14%±3.67%vs13.16%±1.84%;28.68%±2.55%vs19.58%±2.78%;均P<0.05).West-ern blot结果显示,在20d、40d时,CP组胰腺组织TβRⅡ表达显著高于其余各组(20d:0.74±0.05vs0.47±0.03,0.61±0.03,0.21±0.02;40d:1.01±0.14vs0.64±0.08,0.75±0.04,0.23±0.03;均P<0.05),OP组和OT组在40d时胰腺组织TβRⅡ的表达均比20d时明显增高(0.64±0.08vs0.47±0.03;0.75±0.04vs0.61±0.03;均P<0.05).结论:腹腔注射DDC建立大鼠胰腺纤维化模型,方法有效.OM有显著的抗胰腺纤维化作用,可能与其降低TβRⅡ含量,抑制TGF-β信号转导通路有关.

AIM： To investigate the effect of treatment with oxymatrine on the expression of transforming growth factor β1 type Ⅱreceptor （TGFβ1Ⅱ） in chronic pancreatitis （CP） in rats and to explore the potential anti-fibrotic mechanism of oxymatrine. METHODS： Forty male Wistar rats were ran- domly and equally assigned to four groups： negative control group （NC）, CP group, oxymatrine treatment group （OT）, and oxymatrine preven- tion group （OP）. Each group was further divid- ed into two subgroups for detection at different time points. Except the NC group, pancreatic fibrosis was induced in rats of the other groups by intraperitoneal injections of diethyldithio- carbamate （DDC 700 mg/kg）. Preventive and therapeutic oxymatrine （100 mg/kg） was given to rats of the OT and OP group, respectively. Pancreatic tissue samples were taken for HE and Masson staining to evaluate histological altera- tions. The expression of TGF^RII in pancreatic tissue was detected by Western blot. RESULTS： The contents of collagen fibers in the CP group were significantly higher than those in the other groups （day 20： 22.54% ± 4.45% vs 13.16% ± 1.84%, 19.58% ± 2.78%, 2.45% ± 0.24%; day 40： 35.14% ± 3.27% vs 25.14% ± 3.67%, 28.68% ± 2.55%, 3.0% ± 0.32%; all P 〈 0.05）, and the percentages of collagen area in the OP and OT groups on day 40 were significantly higher than those on day 20 （25.14% ± 3.67% vs 13.16% ± 1.84%; 28.68% ± 2.55% vs 19.58% ± 2.78%; all P 〈 0.05） The expression level of TGFBRII in the CP group was significantly higher than those in the other groups （day 20：0.74 ± 0.05 vs 0.47 ± 0.03, 0.61 ± 0.03, 0.21 ± 0.02; day 40：1.01 ± 0.14 vs 0.64 ± 0.08, 0.75 ± 0.04, 0.23 ± 0.03; all P 〈 0.05）. The expression levels of TGFβ1Ⅱ in the OP and OT groups on day 40 were significantly higher than those on day 20 （0.64 ± 0.08 vs 0.47 ± 0.03; 0.75 ± 0.04 vs 0.61 ± 0.03; all P 〈 0.05）. CONCLUSION： Treatment with oxymatrine exerts beneficial effects against CP possibly by inhibiting TGFβ1Ⅱ signaling.