Increased Hes1 expression to regulate differentiation of liver epithelial progenitor cells into cholangiocytes / 西安交通大学学报(医学版)

【Objective】 To use hairy enhancer of split 1 (Hes1) to regulate the differentiation of liver epithelial progenitor cells (LEPCs) into cholangiocytes. 【Methods】 The vectors, pTet-on and pTRE2hyg-Hes1, were transfected into LEPCs. The expression of Hes1 was induced by doxycycline (DOX) with different concentrations (0, 0.1, 1, 5, 10, 50, 100 and 500 μg/mL). The expressions of Hes1, molecular markers of hepatocyte and cholangiocyte, glutathione synthetase (Gss), keratin 19 (Krt19) and hepatic nuclear factor 1β (HNF1β) in LEPCs were verified by Western blotting, RT-PCR, Real-time PCR, immunocytochemistry and immunofluorescence. 【Results】 The expression of Hes1 in LEPCs transfected by pTet-on/pTRE2hyg-Hes1 was increased by 11.21 fold when induced by DOX at 10 ug/mL, which drove the LEPCs to differentiate into biliary epithelial cells. With increasing expression of Hes1, cholangiocyte markers, Krt19 and HNF1β, were significantly upregulated, while the hepatocyte marker, Gss, was obviously downregulated. 【Conclusion】 DOX at 10 μg/mL may induce a suitably up-regulated expression of Hes1 in LEPCs double-transfected by pTet-on and pTRE2hyg-Hes1, and the suitable high-expression rather than over-expression of Hes1 can regulate LEPCs to differentiate into cholangiocytes.

Integrating systematic pharmacology-based strategy and experimental validation to explore mechanism of Tripterygium glycoside on cholangiocyte-related liver injury / 中草药·英文版

Objective: Tripterygium glycoside (TG) is widely used in clinical practice for its multiple bioactivities including anti-inflammatory and immunosuppressive effects. However, emerging studies have frequently reported TG-induced adverse reactions to multiple organs, especially liver. Here, this study aimed to investigate the mechanism of liver damage induced by TG and explore representative components to reflect TG hepatotoxicity. Methods: Network pharmacology was used to determine the potential targets of bile duct injury caused by TG. Next, the hepatotoxic effects of TG, triptolide (TP) and celastrol (CEL) were investigated and compared in vivo and in vitro. Liver function was determined by measuring serum transaminase and histopathology staining. The cell proliferation and apoptosis were determined by cell viability assay, scratch assay and flow cytometry. The expression of gene of interest was determined by qPCR and Western blot. Results: Based on the network pharmacological analysis of 12 bioactive ingredients found in TG, a total of 35 targets and 15 pathways related to bile duct injury were obtained. Both TG and TP resulted in cholangiocyte damage and liver injury, as illustrated by increased levels of serum transaminase and oxidative stress, stimulated portal edema and lymphocytic infiltration and decreased expression of cholangiocyte marker, cytoskeletal 19. In addition, TG and TP inhibited cell proliferation and migration, arrested cell cycle and promoted Caspase-dependent apoptosis of cholangiocytes via suppressing the phosphorylation of extracellular regulated protein kinases 1/2 (ERK1/2) and protein kinase B (AKT). While, CEL at equivalent dosage had no obvious hepatotoxicity. Conclusion: We revealed that TG-stimulated liver injury was specifically characterized by cholangiocyte damage and TP might be the decisive ingredient to reflect TG hepatotoxicity. Our results not only provide novel insights into the mechanism underlying the hepatotoxicity effects of TG but also offer reference for clinical rational use of TG.

Toxicity and mechanisms of celastrol on human biliary epithelial cells / 中草药

Objective: To investigate the toxicity and mechanisms of celastrol (CEL) on human biliary epithelial cells. Methods: The effects of CEL on cell morphology and cell viability changes were observed by CCK-8 experiment and microscope. Cell scratch experiment was used to detect the effect of CEL on cell migration. The effects of CEL on cell cycle and cell apoptosis were detected by flow cytometry. The mRNA and protein expression of apoptosis-related genes Caspase-3, Bax and Bcl-2 were detected by qRT-PCR and Western blotting. Results: CEL inhibited cell proliferation and changed cell morphology at 400-2 000 nmol/L. At 200-800 nmol/L, cell migration was inhibited. At 800-1 200 nmol/L, G0/G1 phase was arrested. At 400-1 200 nmol/L, cell apoptosis was induced and the expression of apoptosis-related genes was increased. Conclusion: CEL showed cholangiocyte toxicity through affecting cell viability, cell migration, preventing cell cycle and promoting cell apoptosis of human biliary epithelial cells.

Bile Acid Transporters Are Expressed and Heterogeneously Distributed in Rat Bile Ducts

BACKGROUND/AIMS: Cholangiocytes are capable of reabsorbing bile salts from bile, but the pathophysiological significance of this process is unclear. To this end, we detected the expression and distribution of bile acid transport proteins in cholangiocytes from normal rat liver and analyzed the possible pathophysiological significance. METHODS: Bile duct tissues of Sprague-Dawley rats were isolated by enzymatic digestion and mechanical isolation, and then divided into large and small bile duct tissues. Immunohistochemistry, real-time polymerase chain reaction and Western blotting were used to determine the expression of the apical sodium-dependent bile acid transporter (ASBT), ileal bile acid binding protein (IBABP), and basolateral organic solute transporter α (Ostα) in the biliary tract system of rats. Differences in the expression and distribution of these proteins were analyzed. RESULTS: In cholangiocytes, ASBT and IBABP were mainly expressed in cholangiocytes of the large bile ducts, in which the expression of both was significantly higher than that in the small ducts (p0.05). CONCLUSIONS: Bile acid transporters are expressed and heterogeneously distributed in rat bile ducts, indicating that bile acid reabsorption by cholangiocytes might mainly occur in the large bile ducts. These findings may help explore the physiology of bile ducts and the pathogenesis of various cholangiopathies.

El hepatocito como un ejemplo de interacción entre la biología celular y las rutas metabólicas / The hepatocyte as an example of the interaction between cellular biology and metabolic pathways

Resumen Encontrar a un representante celular que reúna la estructura y las funciones que se revisan en los cursos de biología celular no es tarea fácil, pero el hepatocito reúne esas características. Además de él, en el hígado hay otras células de interés que vale la pena revisar como un complemento para contar con una visión más general de las múltiples funciones que ocurren en esta glándula. Incluimos algunas imágenes y revisamos algunas funciones de esa maravillosa célula conocida como hepatocito, que además integra a la biología celular y a la bioquímica.

Abstract To find a cell that gathers the functions and the structure that are most commonly reviewed in the cellular biology texts is a difficult task, but the hepatocyte meet these attributes. In addition it, there are other interesting cells in the liver that are important to review as a complement in order to have a general view of the multiple functions that occur in the liver. We included images and reviewed some of the functions of the hepatocyte that integrate cellular biology and biochemistry.

Biology of Cholangiocytes: From Bench to Bedside

Cholangiocytes, the lining epithelial cells in bile ducts, are an important subset of liver cells. They are activated by endogenous and exogenous stimuli and are involved in the modification of bile volume and composition. They are also involved in damaging and repairing the liver. Cholangiocytes have many functions including bile production. They are also involved in transport processes that regulate the volume and composition of bile. Cholangiocytes undergo proliferation and cell death under a variety of conditions. Cholangiocytes have functional and morphological heterogenecity. The immunobiology of cholangiocytes is important, particularly for understanding biliary disease. Secretion of different proinflammatory mediators, cytokines, and chemokines suggests the major role that cholangiocytes play in inflammatory reactions. Furthermore, paracrine secretion of growth factors and peptides mediates extensive cross-talk with other liver cells, including hepatocytes, stellate cells, stem cells, subepithelial myofibroblasts, endothelial cells, and inflammatory cells. Cholangiopathy refers to a category of chronic liver diseases whose primary disease target is the cholangiocyte. Cholangiopathy usually results in end-stage liver disease requiring liver transplant. We summarize the biology of cholangiocytes and redefine the concept of cholangiopathy. We also discuss the recent progress that has been made in understanding the pathogenesis of cholangiopathy and how such progress has influenced therapy.

Imbalance between proliferation and apoptosis of cholangiocytes and its relation to cholangiopathies / 国际外科学杂志

Cholangiocytes are the epithelial cells that line the intrahepatic biliary tree and also the target of cholangiopathies. Despite the heterogeneous etiology ,most of cholangiopathies share the common pathological process which is the imbalance between proliferation and apoptosis of cholangiocytes. The article is a review about the characteristics and mechanism of proliferation and apoptosis of cholangiocytes and their relationship to cholangiopathies.

Physiologic and pathologic experimental models for studying cholangiocytes / 대한간학회지

Cholangiocytes (epithelial cells lining the intra- and extrahepatic bile ducts) and hepatocytes are two major components of liver epithelia. Although cholangiocytes are less numerous than hepatocytes, they are involved in both bile secretion and diverse cellular processes such as cell-cycle phenomena, cell signaling, and interactions with other cells, matrix components, foreign organisms, and xenobiotics. Cholangiocytes are also targets in several human diseases including cholangiocarcinoma, primary sclerosing cholangitis, autoimmune cholangitis, and vanishing bile-duct syndrome. The rapid advances in experimental biology technologies are greatly expanding interest in and knowledge of the physiology and pathophysiology of cholangiocytes. This review focuses on the progress of in vivo and in vitro experimental models in elucidating the physiologic functions of cholangiocytes and the pathophysiology of various cholangiopathies. The following aspects are reviewed: isolation of cholangiocytes from the liver and their heterogeneity, various culture systems, establishment of cholangiocyte cell lines, isolation and usage of intrahepatic bile-duct units, three-dimensional modeling of the bile duct, experimental models for inducing cholangiocyte proliferation, and various cholangiopathies such as cholangiocarcinoma, primary sclerosing cholangitis, and autoimmune cholangitis.