靶向肠道菌群协同调控肝脏胆汁酸代谢研究利胆合剂改善幼龄大鼠胆汁淤积的分子机制

It is difficult to get etiology diagnosis and definitive therapy early for patients with infantile cholestatic hepatopathies (ICH). Some without early treatment will progress to end-stage liver disease. The disorder of bile acid metabolism is the path to the early stage of ICH. Nuclear receptors are junction proteins in regulating liver bile acid metabolism. Recent researches have shown that gut microbiota plays an important coordinate regulation also. The previous clinical studies prove that a Chinese herbal prescription, Li-dan-he-ji, is effective in the treatment of infant jaundice and has the advantage of early symptomatic treatment on ICH. Experimental study also found that single herb effective component in Li-dan-he-ji could alleviate cholestasis of intrahepatic cholestasis model rats and upregulate the expression of FXR in liver. It could also downregulate the serum LPS level of bile duct ligation (BDL) cholestasis model rats. Thus we hypothesize that Li-dan-he-ji improves ICH by targeted gut microbiota regulating liver bile acid metabolism. To test that we will establish BDL animal models with intragastric administration of Li-dan-he-ji. Techniques such as high-throughput sequencing, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis, Western blot and ELISA will be adopted. For mechanistic study, we will comparative analyse the gut microbiota of BDL animal models, serum bile acid spectrum, the expression of key enzymes and transporters involved in synthesis, absorption, transportation on bile acid metabolism. We will illustrate the mechanisms of gut microbiota regulated by Li-dan-he-ji.

婴儿胆汁淤积性肝病(ICH)早期病因诊治困难，若不及时干预，病程将进展至不可逆终末期肝病。胆汁酸（BA）代谢异常是ICH病程早期必经之路，除核受体在BA代谢中起关键调控作用外，新近发现肠道菌群对BA代谢起重要的协同作用。本课题在前期研究证实：利胆合剂能改善婴儿胆汁淤积，组方中单味中药可缓解肝内胆汁淤积模型幼鼠胆汁淤积、上调肝脏FXR表达；下调胆道结扎(BDL)胆汁淤积模型幼鼠血清内毒素（LPS）水平的基础上，提出“利胆合剂靶向肠道菌群协同调控肝脏BA代谢改善ICH的分子机制”的假说，采用高通量测序、高效液相色谱串联质谱(HPLC-MS/MS)分析、Western-blot、ELISA等技术，检测利胆合剂干预BDL胆汁淤积模型幼鼠的肠道菌群结构、血清胆汁酸谱及BA合成、重吸收、转运过程中关键酶和转运体的表达，探讨并初步揭示中药复方利胆合剂靶向肠道菌群改善BA代谢障碍早期治疗ICH的可能机制。