Toll-like receptor 4 shRNA attenuates lipopolysaccharide-induced epithelial-mesenchymal transition of intrahepatic biliary epithelial cells in rats

作者：Tang, Shifang; Jiang, Xiuhan; Wu, Lang; Chen, Shifa; Chen, Ling; Jiang, Jichang; Yan, Pengzhan; Wang, Fang; Tu, Kui; Wang, Dianbei; Gu, Jin; Zhao, Lijin^*

来源：Biomedicine & Pharmacotherapy, 2018, 107: 1210-1217.

DOI：10.1016/j.biopha.2018.08.071

• Epithelial-mesenchymal transition
• Lipopolysaccharide
• Toll-like receptor 4
• Short hairpin RNA
• NF-kappa B/snail signaling

Background and aim: Intrahepatic biliary epithelial cells (IBECs) of the bile duct in liver tissue of patients with hepatolithiasis promoted the development of diseases through epithelial-mesenchymal transition (EMT). This study investigated whether lipopolysaccharide (LPS), a cell-wall constituent of gram-negative bacteria, could induce EMT of IBECs and toll-like receptor 4 (TLR4) had a regulatory role via activating the nuclear factor-kappa B (NF-kappa B)/Snail signaling pathway during this process in vivo. @@@ Methods: TLR4 short hairpin RNA (shRNA) adenovirus or negative control shRNA (NC shRNA) adenovirus (1 x 10(9) plaque-forming unit (PFU), respectively) was injected into the caudal vein of rats. After 96 h, 1 mg/kg LPS was infused retrogradely into the common bile duct for 48 h per rat. The effects of TLR4 shRNA on LPS-induced EMT were determined by evaluating the histopathological changes in IBECs using hematoxylin and eosin staining and the changes in the levels of EMT markers, TLR4, NF-kappa B p65, pNF-kappa B p65, and Snail using real-time polymerase chain reaction and Western blot analysis. @@@ Results: Compared with normal saline treatment, a loss of epithelial cell markers (E-cadherin and cytokeratin 7) and a gain of mesenchymal cell markers (N-cadherin and matrix metalloproteinase 2) were revealed. The levels of TLR4, NF-kappa B phosphorylation, and Snail significantly increased after LPS treatment, whereas pretreatment with TLR4 shRNA inhibited the LPS-induced EMT by downregulating the NF-kappa B/Snail signaling pathway. @@@ Conclusions: LPS induced the EMT of IBECs by activating TLR4. The RNAi-mediated knockdown of TLR4 suppressed EMT occurrence via downregulating the NF-kappa B/Snail signaling pathway, implicating TLR4 as a new target for human hepatolithiasis.

• 出版日期2018-11
• 单位贵州省人民医院; 遵义医科大学