miR-296-3p对胆总管结扎诱导的大鼠肝纤维化的影响

Effect of miR-296-3p on hepatic fibrosis induced by bile duct ligation in rats

目的探究微小RNA-296-3p(miR-296-3p)对胆总管结扎(BDL)诱导的大鼠肝纤维化的影响。方法将25只SD大鼠随机分为假手术(sham)组、模型(BDL)组、NC adv组、miR-296-3p adv组和miR-296-3p sponge adv组,每组5只。通过苏木精-伊红(HE)、Masson染色和天狼星红(Sirius Red)染色观察大鼠肝组织病理变化;比较各组大鼠血清中丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)和总胆红素(TBIL)含量;用qRT-PCR检测大鼠肝组织中miR-296-3p、白介素(IL)-6、IL-1β、肿瘤坏死因子(TNF)-α的表达水平以及平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原(Col1A1)、结缔组织生长因子(CTGF)mRNA的表达水平;Western blot检测α-SMA、Col1A1、CTGF蛋白的表达水平;免疫组织化学染色(IHC)检测α-SMA的表达水平;生物信息学网站预测miR-296-3p的候选靶基因;检测锌指和BTB结构域蛋白20(ZBTB20)mRNA和蛋白的表达水平。结果病理学染色结果显示,与sham组相比,BDL组和NC adv组大鼠肝组织中大量炎症细胞浸润和胶原沉积,与NC adv组相比,miR-296-3p adv组肝组织中炎症细胞减少,胶原沉积减少,而miR-296-3p sponge adv组胶原聚积和炎症反应加重。与sham组相比,BDL组和NC adv组大鼠血清ALT、AST、TBIL含量升高,miR-296-3p的表达水平降低,IL-6、IL-1β、TNF-αmRNA的表达水平及α-SMA、Col1A1、CTGF mRNA和蛋白表达水平均升高(P<0.05);与NC adv组相比,miR-296-3p adv组大鼠血清ALT、AST、TBIL含量降低,miR-296-3p表达水平升高,IL-6、IL-1β、TNF-αmRNA的表达水平降低且肝组织中α-SMA、Col1A1、CTGF mRNA和蛋白表达水平均降低(P<0.05),miR-296-3p sponge adv组结果与miR-296-3p adv组结果相反(P<0.05)。生物信息学网站预测到ZBTB20可能是miR-296-3p的候选靶基因。与sham组相比,BDL组和NC adv组大鼠肝组织中ZBTB20 mRNA和蛋白表达升高(P<0.05),与NC adv组相比,miR-296-3p adv组肝组织中ZBTB20表达降低(P<0.05),而miR-296-3p sponge adv组肝组织中ZBTB20表达升高(P<0.05)。结论miR-296-3p在BDL诱导的大鼠肝纤维化组织中表达水平降低,miR-296-3p可能通过靶定ZBTB20抑制BDL大鼠肝纤维化。

Objective To explore the effect of miR-296-3p on hepatic fibrosis induced by bile duct ligation(BDL)in rats.Methods 25 SD rats were randomly divided into sham group,model(BDL)group,NC adv group,miR-296-3p adv group and miR-296-3p sponge adv group,with 5 rats in each group.The pathological changes were observed in rat liver tissue via HE,Masson and Sirius Red staining;the levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and total bilirubin(TBIL)in the serum of rat in each group were detected;the expression levels of miR-296-3p,interleukin(IL)-6,IL-1β,tumor necrosis factor(TNF)-αand smooth muscle actin(α-SMA),type I collagen(Col1A1),and connective tissue growth factor(CTGF)mRNA in rat liver tissue were detected by qRT-PCR;the expression levels ofα-SMA,Col1A1 and CTGF proteins were detected by Western blot.Immunohistochemical staining(IHC)was performed to detect the expression ofα-SMA in liver tissue.Target genes of miR-296-3p was predicted by bioinformatic analysis using the online database.Zinc finger and BTB domain-containing protein20(ZBTB20)mRNA and protein expression levels were detected.Results The pathological staining results showed that compared with sham group,a large number of infiltrated inflammatory cells and collagen deposition were observed in the liver tissues of rats in the BDL group and NC adv group.Compared with NC adv group,the inflammatory cells and collagen deposition decreased in the liver tissues of miR-296-3p adv group.However,in miR-296-3p sponge adv group,collagen product and inflammatory reaction increased.Compared with sham group,the contents of ALT,AST and TBIL in serum of rats in BDL group and NC adv group increased,the expression level of miR-296-3p decreased,the mRNA expression levels of IL-6,IL-1β,TNF-αincreased,and the mRNA and protein expression levels ofα-SMA,Col1A1 and CTGF increased(all P<0.05).Compared with the NC adv group,the contents of ALT,AST and TBIL in serum of rats in miR-296-3p adv group decreased,the expression level of miR-296-3p increased,the mRNA expression levels of IL-6,IL-1βand TNF-α,and the mRNA and protein expression levels ofα-SMA,Col1A1 and CTGF in liver tissues decreased(all P<0.05).The results of miR-296-3p sponge adv group were opposite to those of miR-296-3p adv group(all P<0.05).The bioinformatics website predicted that ZBTB20 might be a candidate target gene of miR-296-3p.Compared with sham group,the expression of ZBTB20 mRNA and protein in the liver tissues of BDL group and NC adv group increased(P<0.05),and the expression of ZBTB20 in the liver tissues of miR-296-3p adv group decreased compared with NC adv group(P<0.05).However,the expression of ZBTB20 in liver tissues of miR-296-3p sponge adv group increased(P<0.05).Conclusion miR-296-3p expression decreases in BDL-induced hepatic fibrosis in rats,and miR-296-3p may inhibit hepatic fibrosis in BDL rats by targeting ZBTB20.