Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, National Demonstration Center for Experimental Basic Medical Science Education, Laboratory of Infection and Immunity, Xuzhou Medical University, Xuzhou 221004, Jiangsu Province, China.
Department of Laboratory Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, Jiangsu Province, China.
World J Gastroenterol. 2024 Feb 7;30(5):471-484. doi: 10.3748/wjg.v30.i5.471.
Primary sclerosing cholangitis (PSC) is characterized by chronic inflammation and it predisposes to cholangiocarcinoma due to lack of effective treatment options. Recombinant adeno-associated virus (rAAV) provides a promising platform for gene therapy on such kinds of diseases. A microRNA (miRNA) let-7a has been reported to be associated with the progress of PSC but the potential therapeutic implication of inhibition of let-7a on PSC has not been evaluated.
To investigate the therapeutic effects of inhibition of a miRNA let-7a transferred by recombinant adeno-associated virus 8 (rAAV8) on a xenobiotic-induced mouse model of sclerosing cholangitis.
A xenobiotic-induced mouse model of sclerosing cholangitis was induced by 0.1% 3,5-Diethoxycarbonyl-1,4-Dihydrocollidine (DDC) feeding for 2 wk or 6 wk. A single dose of rAAV8-mediated anti-let-7a-5p sponges or scramble control was injected into mice onset of DDC feeding. Upon sacrifice, the liver and the serum were collected from each mouse. The hepatobiliary injuries, hepatic inflammation and fibrosis were evaluated. The targets of let-7a-5p and downstream molecule NF-κB were detected using Western blot.
rAAV8-mediated anti-let-7a-5p sponges can depress the expression of let-7a-5p in mice after DDC feeding for 2 wk or 6 wk. The reduced expression of let-7a-5p can alleviate hepato-biliary injuries indicated by serum markers, and prevent the proliferation of cholangiocytes and biliary fibrosis. Furthermore, inhibition of let-7a mediated by rAAV8 can increase the expression of potential target molecules such as suppressor of cytokine signaling 1 and Dectin1, which consequently inhibit of NF-κB-mediated hepatic inflammation.
Our study demonstrates that a rAAV8 vector designed for liver-specific inhibition of let-7a-5p can potently ameliorate symptoms in a xenobiotic-induced mouse model of sclerosing cholangitis, which provides a possible clinical translation of PSC of human.
原发性硬化性胆管炎（PSC）的特征为慢性炎症，由于缺乏有效治疗方法，易发生胆管癌。重组腺相关病毒（rAAV）为治疗此类疾病提供了有前途的基因治疗平台。已报道 microRNA（miRNA）let-7a 与 PSC 的进展有关，但抑制 let-7a 对 PSC 的潜在治疗意义尚未得到评估。
研究重组腺相关病毒 8（rAAV8）转染的 miRNA let-7a 抑制剂对异生物诱导的硬化性胆管炎小鼠模型的治疗作用。
采用 0.1%3,5-二乙氧基羰基-1,4-二氢吡啶（DDC）喂养 2 周或 6 周诱导异生物诱导的硬化性胆管炎小鼠模型。在开始 DDC 喂养时，向小鼠单次注射 rAAV8 介导的抗 let-7a-5p 海绵或对照物。处死时，从每只小鼠中收集肝脏和血清。评估肝胆损伤、肝炎症和纤维化。使用 Western blot 检测 let-7a-5p 的靶标和下游分子 NF-κB。
rAAV8 介导的抗 let-7a-5p 海绵可降低 DDC 喂养 2 周或 6 周后小鼠中 let-7a-5p 的表达。let-7a-5p 表达减少可减轻血清标志物所示的肝胆损伤，并防止胆管细胞增殖和胆管纤维化。此外，rAAV8 介导的 let-7a 抑制可增加潜在靶标分子如细胞因子信号转导抑制因子 1 和 Dectin1 的表达，从而抑制 NF-κB 介导的肝炎症。
本研究表明，针对肝脏特异性抑制 let-7a-5p 的 rAAV8 载体可有效改善异生物诱导的硬化性胆管炎小鼠模型的症状，为人类 PSC 的临床转化提供了可能。
