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Xie S, Wei S, Ma X, Wang R, He T, Zhang Z, Yang J, Wang J, Chang L, Jing M, Li H, Zhou X, Zhao Y. Genetic alterations and molecular mechanisms underlying hereditary intrahepatic cholestasis. Front Pharmacol 2023; 14:1173542. [PMID: 37324459 PMCID: PMC10264785 DOI: 10.3389/fphar.2023.1173542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/16/2023] [Indexed: 06/17/2023] Open
Abstract
Hereditary cholestatic liver disease caused by a class of autosomal gene mutations results in jaundice, which involves the abnormality of the synthesis, secretion, and other disorders of bile acids metabolism. Due to the existence of a variety of gene mutations, the clinical manifestations of children are also diverse. There is no unified standard for diagnosis and single detection method, which seriously hinders the development of clinical treatment. Therefore, the mutated genes of hereditary intrahepatic cholestasis were systematically described in this review.
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Affiliation(s)
- Shuying Xie
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Shizhang Wei
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Xiao Ma
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ruilin Wang
- Department of Pharmacy, 5th Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Tingting He
- Department of Pharmacy, 5th Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Zhao Zhang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ju Yang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jiawei Wang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Lei Chang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Manyi Jing
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
| | - Haotian Li
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
| | - Xuelin Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yanling Zhao
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
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2
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Harnessing conserved signaling and metabolic pathways to enhance the maturation of functional engineered tissues. NPJ Regen Med 2022; 7:44. [PMID: 36057642 PMCID: PMC9440900 DOI: 10.1038/s41536-022-00246-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/05/2022] [Indexed: 11/08/2022] Open
Abstract
The development of induced-pluripotent stem cell (iPSC)-derived cell types offers promise for basic science, drug testing, disease modeling, personalized medicine, and translatable cell therapies across many tissue types. However, in practice many iPSC-derived cells have presented as immature in physiological function, and despite efforts to recapitulate adult maturity, most have yet to meet the necessary benchmarks for the intended tissues. Here, we summarize the available state of knowledge surrounding the physiological mechanisms underlying cell maturation in several key tissues. Common signaling consolidators, as well as potential synergies between critical signaling pathways are explored. Finally, current practices in physiologically relevant tissue engineering and experimental design are critically examined, with the goal of integrating greater decision paradigms and frameworks towards achieving efficient maturation strategies, which in turn may produce higher-valued iPSC-derived tissues.
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3
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Acevedo‐Acevedo S, Stefkovich ML, Kang SWS, Cunningham RP, Cultraro CM, Porat‐Shliom N. LKB1 acts as a critical brake for the glucagon-mediated fasting response. Hepatol Commun 2022; 6:1949-1961. [PMID: 35357082 PMCID: PMC9315124 DOI: 10.1002/hep4.1942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/23/2022] [Accepted: 03/06/2022] [Indexed: 11/08/2022] Open
Abstract
As important as the fasting response is for survival, an inability to shut it down once nutrients become available can lead to exacerbated disease and severe wasting. The liver is central to transitions between feeding and fasting states, with glucagon being a key initiator of the hepatic fasting response. However, the precise mechanisms controlling fasting are not well defined. One potential mediator of these transitions is liver kinase B1 (LKB1), given its role in nutrient sensing. Here, we show LKB1 knockout mice have a severe wasting and prolonged fasting phenotype despite increased food intake. By applying RNA sequencing and intravital microscopy, we show that loss of LKB1 leads to a dramatic reprogramming of the hepatic lobule through robust up-regulation of periportal genes and functions. This is likely mediated through the opposing effect that LKB1 has on glucagon pathways and gene expression. Conclusion: Our findings show that LKB1 acts as a brake to the glucagon-mediated fasting response, resulting in "periportalization" of the hepatic lobule and whole-body metabolic inefficiency. These findings reveal a mechanism by which hepatic metabolic compartmentalization is regulated by nutrient-sensing.
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Affiliation(s)
- Suehelay Acevedo‐Acevedo
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
| | - Megan L. Stefkovich
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
| | - Sun Woo Sophie Kang
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
| | - Rory P. Cunningham
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
| | - Constance M. Cultraro
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
| | - Natalie Porat‐Shliom
- Thoracic and GI Malignancies BranchCenter for Cancer ResearchNational Cancer Institute, NIHBethesdaMarylandUSA
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4
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Takemura A, Ito K. In Vitro Assay System to Detect Drug-Induced Bile Acid-Dependent Cytotoxicity Using Hepatocytes. Methods Mol Biol 2022; 2544:119-127. [PMID: 36125714 DOI: 10.1007/978-1-0716-2557-6_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Inhibition of bile acid excretion by drugs is a significant factor in the development of drug-induced cholestatic liver injury. We constructed a new in vitro assay system to detect bile acid-dependent cytotoxicity in hepatocytes. This cell-based system can assess the toxicity of the parent compound, as well as the contribution of metabolite(s). In addition, this system can utilize several types of hepatocytes (primary hepatocytes, hepatoma cell line, and induced pluripotent stem cell-induced hepatocytes). In this chapter, a method to detect drug-induced bile acid-dependent toxicity in hepatocytes is described.
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Affiliation(s)
- Akinori Takemura
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Kousei Ito
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan.
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5
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Abstract
Hepatocytes are liver parenchymal cells involved in performing various metabolic reactions. During the development of therapeutic drugs, toxicological assays are conducted using hepatocyte cultures before clinical trials. However, since primary hepatocytes cannot proliferate and rapidly lose their functions in vitro, many efforts have been put into modifying culture conditions to expand primary hepatocytes and induce hepatocyte functions in intrinsic and extrinsic stem/progenitor cells. In this chapter, we summarize recent advances in preparing hepatocyte cultures and induction of hepatocytes from various cellular sources.
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Affiliation(s)
- Ayumu Okumura
- Division of Regenerative Medicine, Center for Stem Cell Biology and Regenerative Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Naoki Tanimizu
- Division of Regenerative Medicine, Center for Stem Cell Biology and Regenerative Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan.
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6
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Fu D. Collagen Sandwich Culture of Primary Hepatocytes for Image-Based Investigations. Methods Mol Biol 2022; 2544:159-169. [PMID: 36125717 DOI: 10.1007/978-1-0716-2557-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Collagen sandwich culture of hepatocytes retains many in vivo-like properties and is used for many investigations in liver cell biology, and hepatic pharmacology and toxicology. This chapter describes the method of establishing collagen sandwich culture of hepatocytes in a glass bottom dish for image-based studies.
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Affiliation(s)
- Dong Fu
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- In vivo Pharmacology and Toxicology, Frontera Therapeutics, Bedford, MA, USA.
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7
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Ren T, Pang L, Dai W, Wu S, Kong J. Regulatory mechanisms of the bile salt export pump (BSEP/ABCB11) and its role in related diseases. Clin Res Hepatol Gastroenterol 2021; 45:101641. [PMID: 33581308 DOI: 10.1016/j.clinre.2021.101641] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/03/2021] [Accepted: 01/21/2021] [Indexed: 02/04/2023]
Abstract
The bile salt export pump (BSEP/ABCB11) is located on the apical membrane and mediates the secretion of bile salts from hepatocytes into the bile. BSEP-mediated bile salt efflux is the rate-limiting step of bile salt secretion and the main driving force of bile flow. BSEP drives and maintains the enterohepatic circulation of bile salts. In recent years, research efforts have been focused on understanding the physiological and pathological functions and regulatory mechanisms of BSEP. These studies elucidated the roles of farnesoid X receptor (FXR), AMP-activated protein kinase (AMPK), liver receptor homolog-1(LRH-1) and nuclear factor erythroid 2-related factor 2 (Nrf-2) in BSEP expression and discovered some regulatory factors which participate in its post-transcriptional regulation. A series of liver diseases have also been shown to be related to BSEP expression and dysfunction, such as cholestasis, drug-induced liver injury, and gallstones. Here, we systematically review and summarize recent literature on BSEP structure, physiological functions, regulatory mechanisms, and related diseases.
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Affiliation(s)
- Tengqi Ren
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Liwei Pang
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Wanlin Dai
- Innovation Institute of China Medical University, Shenyang, Liaoning, China
| | - Shuodong Wu
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Jing Kong
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China.
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8
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Tocan V, Hayase J, Kamakura S, Kohda A, Ohga S, Kohjima M, Sumimoto H. Hepatocyte polarity establishment and apical lumen formation are organized by Par3, Cdc42, and aPKC in conjunction with Lgl. J Biol Chem 2021; 297:101354. [PMID: 34717957 PMCID: PMC8637150 DOI: 10.1016/j.jbc.2021.101354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/17/2021] [Accepted: 10/19/2021] [Indexed: 01/21/2023] Open
Abstract
Hepatocytes differ from columnar epithelial cells by their multipolar organization, which follows the initial formation of central lumen-sharing clusters of polarized cells as observed during liver development and regeneration. The molecular mechanism for hepatocyte polarity establishment, however, has been comparatively less studied than those for other epithelial cell types. Here, we show that the tight junction protein Par3 organizes hepatocyte polarization via cooperating with the small GTPase Cdc42 to target atypical protein kinase C (aPKC) to a cortical site near the center of cell-cell contacts. In 3D Matrigel culture of human hepatocytic HepG2 cells, which mimics a process of liver development and regeneration, depletion of Par3, Cdc42, or aPKC results in an impaired establishment of apicobasolateral polarity and a loss of subsequent apical lumen formation. The aPKC activity is also required for bile canalicular (apical) elongation in mouse primary hepatocytes. The lateral membrane-associated proteins Lgl1 and Lgl2, major substrates of aPKC, seem to be dispensable for hepatocyte polarity establishment because Lgl-depleted HepG2 cells are able to form a single apical lumen in 3D culture. On the other hand, Lgl depletion leads to lateral invasion of aPKC, and overexpression of Lgl1 or Lgl2 prevents apical lumen formation, indicating that they maintain proper lateral integrity. Thus, hepatocyte polarity establishment and apical lumen formation are organized by Par3, Cdc42, and aPKC; Par3 cooperates with Cdc42 to recruit aPKC, which plays a crucial role in apical membrane development and regulation of the lateral maintainer Lgl.
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Affiliation(s)
- Vlad Tocan
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Junya Hayase
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Sachiko Kamakura
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Akira Kohda
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Shouichi Ohga
- Department of Pediatrics, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Motoyuki Kohjima
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan; Department of Medicine and Regulatory Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Hideki Sumimoto
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
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9
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Belicova L, Repnik U, Delpierre J, Gralinska E, Seifert S, Valenzuela JI, Morales-Navarrete HA, Franke C, Räägel H, Shcherbinina E, Prikazchikova T, Koteliansky V, Vingron M, Kalaidzidis YL, Zatsepin T, Zerial M. Anisotropic expansion of hepatocyte lumina enforced by apical bulkheads. J Cell Biol 2021; 220:212522. [PMID: 34328499 PMCID: PMC8329733 DOI: 10.1083/jcb.202103003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/11/2021] [Accepted: 07/08/2021] [Indexed: 12/20/2022] Open
Abstract
Lumen morphogenesis results from the interplay between molecular pathways and mechanical forces. In several organs, epithelial cells share their apical surfaces to form a tubular lumen. In the liver, however, hepatocytes share the apical surface only between adjacent cells and form narrow lumina that grow anisotropically, generating a 3D network of bile canaliculi (BC). Here, by studying lumenogenesis in differentiating mouse hepatoblasts in vitro, we discovered that adjacent hepatocytes assemble a pattern of specific extensions of the apical membrane traversing the lumen and ensuring its anisotropic expansion. These previously unrecognized structures form a pattern, reminiscent of the bulkheads of boats, also present in the developing and adult liver. Silencing of Rab35 resulted in loss of apical bulkheads and lumen anisotropy, leading to cyst formation. Strikingly, we could reengineer hepatocyte polarity in embryonic liver tissue, converting BC into epithelial tubes. Our results suggest that apical bulkheads are cell-intrinsic anisotropic mechanical elements that determine the elongation of BC during liver tissue morphogenesis.
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Affiliation(s)
- Lenka Belicova
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Urska Repnik
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Julien Delpierre
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Elzbieta Gralinska
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Sarah Seifert
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | | | - Christian Franke
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Helin Räägel
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Nelson Laboratories LLC, Salt Lake City, UT
| | | | | | | | - Martin Vingron
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | - Timofei Zatsepin
- Skolkovo Institute of Science and Technology, Skolkovo, Russia.,Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Marino Zerial
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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10
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Faradonbeh FA, Sa II, Lastuvkova H, Cermanova J, Hroch M, Faistova H, Mokry J, Nova Z, Uher M, Nachtigal P, Pavek P, Micuda S. Metformin impairs bile acid homeostasis in ethinylestradiol-induced cholestasis in mice. Chem Biol Interact 2021; 345:109525. [PMID: 34058177 DOI: 10.1016/j.cbi.2021.109525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/28/2021] [Accepted: 05/16/2021] [Indexed: 12/12/2022]
Abstract
Metformin, an oral antidiabetic drug, recently demonstrated a reducing effect on bile acids (BA) plasma concentrations in one patient with intrahepatic cholestasis of pregnancy (ICP) by unknown mechanism. Therefore, the aim of the present study was to examine the effect of metformin on BA homeostasis and related molecular pathways in the liver and intestine using a mouse model of ICP. The cholestasis was induced in female C57BL/6 mice by repeated administration of ethinylestradiol (10 mg/kg BW s.c.) and/or metformin (150 mg/kg BW orally) over 5 consecutive days with subsequent bile collection and molecular analysis of samples. We demonstrated that metformin significantly increased the rate of bile secretion in control mice. This increase was BA dependent and was produced both by increased liver BA synthesis via induced cholesterol 7α-hydroxylase (Cyp7a1) and by increased BA reabsorption in the ileum via induction of the apical sodium-dependent BA transporter (Asbt). In contrast, metformin further worsened ethinylestradiol-induced impairment of bile secretion. This reduction was also BA dependent and corresponded with significant downregulation of Bsep, and Ntcp, major excretory and uptake transporters for BA in hepatocytes, respectively. The plasma concentrations of BA were consequently significantly increased in the metformin-treated mice. Altogether, our data indicate positive stimulation of bile secretion by metformin in the intact liver, but this drug also induces serious impairment of BA biliary secretion, with a marked increase in plasma concentrations in estrogen-induced cholestasis. Our results imply that metformin should be used with caution in situations with hormone-dependent cholestasis, such as ICP.
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Affiliation(s)
- Fatemeh Alaei Faradonbeh
- Department of Pharmacology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Ivone Igreja Sa
- Department of Biological and Medical Sciences, Charles University, Faculty of Pharmacy in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Hana Lastuvkova
- Department of Pharmacology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Jolana Cermanova
- Department of Pharmacology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Milos Hroch
- Department of Medical Biochemistry, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Hana Faistova
- Department of Pathology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Jaroslav Mokry
- Department of Histology and Embryology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Zuzana Nova
- Department of Pharmacology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Martin Uher
- Department of Medical Biochemistry, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Petr Nachtigal
- Department of Biological and Medical Sciences, Charles University, Faculty of Pharmacy in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Petr Pavek
- Department of Pharmacology and Toxicology, Charles University, Faculty of Pharmacy in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Stanislav Micuda
- Department of Pharmacology, Charles University, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic.
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Molecular Regulation of Canalicular ABC Transporters. Int J Mol Sci 2021; 22:ijms22042113. [PMID: 33672718 PMCID: PMC7924332 DOI: 10.3390/ijms22042113] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 12/17/2022] Open
Abstract
The ATP-binding cassette (ABC) transporters expressed at the canalicular membrane of hepatocytes mediate the secretion of several compounds into the bile canaliculi and therefore play a key role in bile secretion. Among these transporters, ABCB11 secretes bile acids, ABCB4 translocates phosphatidylcholine and ABCG5/G8 is responsible for cholesterol secretion, while ABCB1 and ABCC2 transport a variety of drugs and other compounds. The dysfunction of these transporters leads to severe, rare, evolutionary biliary diseases. The development of new therapies for patients with these diseases requires a deep understanding of the biology of these transporters. In this review, we report the current knowledge regarding the regulation of canalicular ABC transporters' folding, trafficking, membrane stability and function, and we highlight the role of molecular partners in these regulating mechanisms.
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12
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Sohail MI, Dönmez-Cakil Y, Szöllősi D, Stockner T, Chiba P. The Bile Salt Export Pump: Molecular Structure, Study Models and Small-Molecule Drugs for the Treatment of Inherited BSEP Deficiencies. Int J Mol Sci 2021; 22:E784. [PMID: 33466755 PMCID: PMC7830293 DOI: 10.3390/ijms22020784] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 02/07/2023] Open
Abstract
The bile salt export pump (BSEP/ABCB11) is responsible for the transport of bile salts from hepatocytes into bile canaliculi. Malfunction of this transporter results in progressive familial intrahepatic cholestasis type 2 (PFIC2), benign recurrent intrahepatic cholestasis type 2 (BRIC2) and intrahepatic cholestasis of pregnancy (ICP). Over the past few years, several small molecular weight compounds have been identified, which hold the potential to treat these genetic diseases (chaperones and potentiators). As the treatment response is mutation-specific, genetic analysis of the patients and their families is required. Furthermore, some of the mutations are refractory to therapy, with the only remaining treatment option being liver transplantation. In this review, we will focus on the molecular structure of ABCB11, reported mutations involved in cholestasis and current treatment options for inherited BSEP deficiencies.
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Affiliation(s)
| | - Yaprak Dönmez-Cakil
- Department of Histology and Embryology, Faculty of Medicine, Maltepe University, Maltepe, 34857 Istanbul, Turkey;
| | - Dániel Szöllősi
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Waehringerstrasse, 13A, 1090 Vienna, Austria;
| | - Thomas Stockner
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Waehringerstrasse, 13A, 1090 Vienna, Austria;
| | - Peter Chiba
- Institute of Medical Chemistry, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Waehringerstrasse, 10, 1090 Vienna, Austria
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13
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Yang T, Wang X, Zhou Y, Yu Q, Heng C, Yang H, Yuan Z, Miao Y, Chai Y, Wu Z, Sun L, Huang X, Liu B, Jiang Z, Zhang L. SEW2871 attenuates ANIT-induced hepatotoxicity by protecting liver barrier function via sphingosine 1-phosphate receptor-1-mediated AMPK signaling pathway. Cell Biol Toxicol 2021; 37:595-609. [PMID: 33400020 DOI: 10.1007/s10565-020-09567-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 10/27/2020] [Indexed: 01/06/2023]
Abstract
Cholestatic liver injury, a group of diseases characterized with dysregulated bile acid (BA) homeostasis, was partly resulted from BA circulation disorders, which is commonly associated with the damage of hepatocyte barrier function. However, the underlying hepatocyte barrier-protective molecular mechanisms of cholestatic liver injury remain poorly understood. Interestingly, recent studies have shown that sphingosine-1-phosphate (S1P) participated in the process of cholestasis by activating its G protein-coupled receptors S1PRs, regaining the integrity of hepatocyte tight junctions (TJs). Here, we showed that SEW2871, a selective agonist of sphingosine-1-phosphate receptor 1(S1PR1), alleviated ANIT-induced TJs damage in 3D-cultured mice primary hepatocytes. Molecular mechanism studies indicated that AMPK signaling pathways was involved in TJs protection of SEW2871 in ANIT-induced hepatobiliary barrier function deficiency. AMPK antagonist compound C (CC) and agonist AICAR were all used to further identify the important role of AMPK signaling pathway in SEW2871's TJs protection of ANIT-treated mice primary hepatocytes. The in vivo data showed that SEW2871 ameliorated ANIT-induced cholestatic hepatotoxicity. Further protection mechanism research demonstrated that SEW2871 not only regained hepatocyte TJs by the upregulated S1PR1 via AMPK signaling pathway, but also recovered hepatobiliary barrier function deficiency, which was verified by the restored BA homeostasis by using of high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). These results revealed that the increased expression of S1PR1 induced by SEW2871 could ameliorate ANIT-induced cholestatic liver injury through improving liver barrier function via AMPK signaling and subsequently reversed the disrupted BA homeostasis. Our study provided strong evidence that S1PR1 may be a promising therapeutic approach for treating intrahepatic cholestatic liver injury. Graphical abstract.
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Affiliation(s)
- Tingting Yang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, 221004, China
| | - Xue Wang
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Yi Zhou
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, 221004, China
| | - Qiongna Yu
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Cai Heng
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, 221004, China
| | - Hao Yang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, 221004, China
| | - Zihang Yuan
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Yingying Miao
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Yuanyuan Chai
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Ziteng Wu
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Lixin Sun
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China
| | - Xin Huang
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China.,Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing, 210009, China
| | - Bing Liu
- Department of Pharmacology, School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Zhenzhou Jiang
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China. .,Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing, 210009, China.
| | - Luyong Zhang
- Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou, 510006, China. .,New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, China.
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14
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Engin A. Bile Acid Toxicity and Protein Kinases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1275:229-258. [PMID: 33539018 DOI: 10.1007/978-3-030-49844-3_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
If the bile acids reach to pathological concentrations due to cholestasis, accumulation of hydrophobic bile acids within the hepatocyte may result in cell death. Thus, hydrophobic bile acids induce apoptosis in hepatocytes, while hydrophilic bile acids increase intracellular adenosine 3',5'-monophosphate (cAMP) levels and activate mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways to protect hepatocytes from apoptosis.Two apoptotic pathways have been described in bile acids-induced death. Both are controlled by multiple protein kinase signaling pathways. In mitochondria-controlled pathway, caspase-8 is activated with death domain-independent manner, whereas, Fas-dependent classical pathway involves ligand-independent oligomerization of Fas.Hydrophobic bile acids dose-dependently upregulate the inflammatory response by further stimulating production of inflammatory cytokines. Death receptor-mediated apoptosis is regulated at the cell surface by the receptor expression, at the death-inducing signaling complex (DISC) by expression of procaspase-8, the death receptors Fas-associated death domain (FADD), and cellular FADD-like interleukin 1-beta (IL-1β)-converting enzyme (FLICE) inhibitory protein (cFLIP). Bile acids prevent cFLIP recruitment to the DISC and thereby enhance initiator caspase activation and lead to cholestatic apoptosis. At mitochondria, the expression of B-cell leukemia/lymphoma-2 (Bcl-2) family proteins contribute to apoptosis by regulating mitochondrial cytochrome c release via Bcl-2, Bcl-2 homology 3 (BH3) interacting domain death agonist (Bid), or Bcl-2 associated protein x (Bax). Fas receptor CD95 activation by hydrophobic bile acids is initiated by reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-dependent reactive oxygen species (ROS) signaling. However, activation of necroptosis by ligands of death receptors requires the kinase activity of receptor interacting protein1 (RIP1), which mediates the activation of RIP3 and mixed lineage kinase domain-like protein (MLKL). In this chapter, mainly the effect of protein kinases signal transduction on the mechanisms of hydrophobic bile acids-induced inflammation, apoptosis, necroptosis and necrosis are discussed.
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Affiliation(s)
- Atilla Engin
- Department of General Surgery, Faculty of Medicine, Gazi University, Ankara, Turkey.
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15
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Sarkadi B, Homolya L, Hegedűs T. The ABCG2/BCRP transporter and its variants - from structure to pathology. FEBS Lett 2020; 594:4012-4034. [PMID: 33015850 DOI: 10.1002/1873-3468.13947] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/27/2020] [Accepted: 09/21/2020] [Indexed: 12/13/2022]
Abstract
The ABCG2 protein has a key role in the transport of a wide range of structurally dissimilar endo- and xenobiotics in the human body, especially in the tissue barriers and the metabolizing or secreting organs. The human ABCG2 gene harbors a high number of polymorphisms and mutations, which may significantly modulate its expression and function. Recent high-resolution structural data, complemented with molecular dynamic simulations, may significantly help to understand intramolecular movements and substrate handling, as well as the effects of mutations on the membrane transporter function of ABCG2. As reviewed here, structural alterations may result not only in direct alterations in drug binding and transporter activity, but also in improper folding or problems in the carefully regulated process of trafficking, including vesicular transport, endocytosis, recycling, and degradation. Here, we also review the clinical importance of altered ABCG2 expression and function in general drug metabolism, cancer multidrug resistance, and impaired uric acid excretion, leading to gout.
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Affiliation(s)
- Balázs Sarkadi
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary.,Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - László Homolya
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Tamás Hegedűs
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
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16
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Burger CA, Alevy J, Casasent AK, Jiang D, Albrecht NE, Liang JH, Hirano AA, Brecha NC, Samuel MA. LKB1 coordinates neurite remodeling to drive synapse layer emergence in the outer retina. eLife 2020; 9:e56931. [PMID: 32378514 PMCID: PMC7237215 DOI: 10.7554/elife.56931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 04/11/2020] [Indexed: 12/04/2022] Open
Abstract
Structural changes in pre and postsynaptic neurons that accompany synapse formation often temporally and spatially overlap. Thus, it has been difficult to resolve which processes drive patterned connectivity. To overcome this, we use the laminated outer murine retina. We identify the serine/threonine kinase LKB1 as a key driver of synapse layer emergence. The absence of LKB1 in the retina caused a marked mislocalization and delay in synapse layer formation. In parallel, LKB1 modulated postsynaptic horizontal cell refinement and presynaptic photoreceptor axon growth. Mislocalized horizontal cell processes contacted aberrant cone axons in LKB1 mutants. These defects coincided with altered synapse protein organization, and horizontal cell neurites were misdirected to ectopic synapse protein regions. Together, these data suggest that LKB1 instructs the timing and location of connectivity in the outer retina via coordinate regulation of pre and postsynaptic neuron structure and the localization of synapse-associated proteins.
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Affiliation(s)
- Courtney A Burger
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Jonathan Alevy
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Anna K Casasent
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Danye Jiang
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Nicholas E Albrecht
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Justine H Liang
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Arlene A Hirano
- Department of Neurobiology, David Geffen School of Medicine at UCLALos AngelesUnited States
- United States Veterans Administration Greater Los Angeles Healthcare SystemLos AngelesUnited States
| | - Nicholas C Brecha
- Department of Neurobiology, David Geffen School of Medicine at UCLALos AngelesUnited States
- United States Veterans Administration Greater Los Angeles Healthcare SystemLos AngelesUnited States
| | - Melanie A Samuel
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
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17
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Amar MJA, Freeman LA, Nishida T, Sampson ML, Pryor M, Vaisman BL, Neufeld EB, Karathanasis SK, Remaley AT. LCAT protects against Lipoprotein-X formation in a murine model of drug-induced intrahepatic cholestasis. Pharmacol Res Perspect 2020; 8:e00554. [PMID: 31893124 PMCID: PMC6935572 DOI: 10.1002/prp2.554] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 12/22/2022] Open
Abstract
Familial lecithin:cholesterol acyltransferase (LCAT) deficiency (FLD) is a rare genetic disease characterized by low HDL-C levels, low plasma cholesterol esterification, and the formation of Lipoprotein-X (Lp-X), an abnormal cholesterol-rich lipoprotein particle. LCAT deficiency causes corneal opacities, normochromic normocytic anemia, and progressive renal disease due to Lp-X deposition in the glomeruli. Recombinant LCAT is being investigated as a potential therapy for this disorder. Several hepatic disorders, namely primary biliary cirrhosis, primary sclerosing cholangitis, cholestatic liver disease, and chronic alcoholism also develop Lp-X, which may contribute to the complications of these disorders. We aimed to test the hypothesis that an increase in plasma LCAT could prevent the formation of Lp-X in other diseases besides FLD. We generated a murine model of intrahepatic cholestasis in LCAT-deficient (KO), wild type (WT), and LCAT-transgenic (Tg) mice by gavaging mice with alpha-naphthylisothiocyanate (ANIT), a drug well known to induce intrahepatic cholestasis. Three days after the treatment, all mice developed hyperbilirubinemia and elevated liver function markers (ALT, AST, Alkaline Phosphatase). The presence of high levels of LCAT in the LCAT-Tg mice, however, prevented the formation of Lp-X and other plasma lipid abnormalities in WT and LCAT-KO mice. In addition, we demonstrated that multiple injections of recombinant human LCAT can prevent significant accumulation of Lp-X after ANIT treatment in WT mice. In summary, LCAT can protect against the formation of Lp-X in a murine model of cholestasis and thus recombinant LCAT could be a potential therapy to prevent the formation of Lp-X in other diseases besides FLD.
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Affiliation(s)
- Marcelo J. A. Amar
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Lita A. Freeman
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Takafumi Nishida
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Maureen L. Sampson
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Milton Pryor
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Boris L. Vaisman
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Edward B. Neufeld
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Sotirios K. Karathanasis
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
- Cardiovascular and Metabolic Disease SectionMedImmuneGaithersburgMDUSA
- NeoProgenBaltimoreMDUSA
| | - Alan T. Remaley
- Lipoprotein Metabolism SectionTranslational Vascular Medicine BranchNational Heart Lung and Blood InstituteNational Institutes of HealthBethesdaMDUSA
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18
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Lu X, Liu L, Shan W, Kong L, Chen N, Lou Y, Zeng S. The Role of the Sodium-taurocholate Co-transporting Polypeptide (NTCP) and Bile Salt Export Pump (BSEP) in Related Liver Disease. Curr Drug Metab 2019; 20:377-389. [PMID: 31258056 DOI: 10.2174/1389200220666190426152830] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 03/10/2019] [Accepted: 03/26/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Sodium Taurocholate Co-transporting Polypeptide (NTCP) and Bile Salt Export Pump (BSEP) play significant roles as membrane transporters because of their presence in the enterohepatic circulation of bile salts. They have emerged as promising drug targets in related liver disease. METHODS We reviewed the literature published over the last 20 years with a focus on NTCP and BSEP. RESULTS This review summarizes the current perception about structure, function, genetic variation, and regulation of NTCP and BSEP, highlights the effects of their defects in some hepatic disorders, and discusses the application prospect of new transcriptional activators in liver diseases. CONCLUSION NTCP and BSEP are important proteins for transportation and homeostasis maintenance of bile acids. Further research is needed to develop new models for determining the structure-function relationship of bile acid transporters and screening for substrates and inhibitors, as well as to gain more information about the regulatory genetic mechanisms involved in the processes of liver injury.
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Affiliation(s)
- Xiaoyang Lu
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Lin Liu
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Wenya Shan
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Limin Kong
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Na Chen
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Yan Lou
- The First Affiliated Hospital, Zhejiang University, Zhejiang, China
| | - Su Zeng
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Zhejiang, China
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19
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Heibel SK, McGuire PJ, Haskins N, Datta Majumdar H, Rayavarapu S, Nagaraju K, Hathout Y, Brown K, Tuchman M, Caldovic L. AMP-activated protein kinase signaling regulated expression of urea cycle enzymes in response to changes in dietary protein intake. J Inherit Metab Dis 2019; 42:1088-1096. [PMID: 31177541 PMCID: PMC7385982 DOI: 10.1002/jimd.12133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/02/2019] [Accepted: 06/05/2019] [Indexed: 12/30/2022]
Abstract
Abundance of urea cycle enzymes in the liver is regulated by dietary protein intake. Although urea cycle enzyme levels rise in response to a high-protein (HP) diet, signaling networks that sense dietary protein intake and trigger changes in expression of urea cycle genes have not been identified. The aim of this study was to identify signaling pathway(s) that respond to changes in protein intake and regulate expression of urea cycle genes in mice and human hepatocytes. Mice were adapted to either HP or low-protein diets followed by isolation of liver protein and mRNA and integrated analysis of the proteomic and transcriptomic data. HP diet led to increased expression of mRNA and enzymes in amino acid degradation pathways and decreased expression of mRNA and enzymes in carbohydrate and fat metabolism, which implicated adenosine monophosphate-activated protein kinase (AMPK) as a possible regulator. Primary human hepatocytes, treated with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) an activator of AMPK, were used to test whether AMPK regulates expression of urea cycle genes. The abundance of carbamoylphosphate synthetase 1 and ornithine transcarbamylase mRNA increased in hepatocytes treated with AICAR, which supports a role for AMPK signaling in regulation of the urea cycle. Because AMPK is either a target of drugs used to treat type-2 diabetes, these drugs might increase the expression of urea cycle enzymes in patients with partial urea cycle disorders, which could be the basis of a new therapeutic approach.
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Affiliation(s)
- Sandra Kirsch Heibel
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | | | - Nantaporn Haskins
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | - Himani Datta Majumdar
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | - Sree Rayavarapu
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | - Kanneboyina Nagaraju
- Department of Pharmaceutical Sciences, Binghamton University, Binghamton NY, USA
| | - Yetrib Hathout
- Department of Pharmaceutical Sciences, Binghamton University, Binghamton NY, USA
| | - Kristy Brown
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | - Mendel Tuchman
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
| | - Ljubica Caldovic
- Center for Genetic Medicine Research, Children’s National Medical Center, 111 Michigan Ave NW, Washington DC, USA
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20
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Roma MG, Barosso IR, Miszczuk GS, Crocenzi FA, Pozzi EJS. Dynamic Localization of Hepatocellular Transporters: Role in Biliary Excretion and Impairment in Cholestasis. Curr Med Chem 2019; 26:1113-1154. [DOI: 10.2174/0929867325666171205153204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 12/25/2022]
Abstract
Bile flow generation is driven by the vectorial transfer of osmotically active compounds from sinusoidal blood into a confined space, the bile canaliculus. Hence, localization of hepatocellular transporters relevant to bile formation is crucial for bile secretion. Hepatocellular transporters are localized either in the plasma membrane or in recycling endosomes, from where they can be relocated to the plasma membrane on demand, or endocytosed when the demand decreases. The balance between endocytic internalization/ exocytic targeting to/from this recycling compartment is therefore the main determinant of the hepatic capability to generate bile, and to dispose endo- and xenobiotics. Furthermore, the exacerbated endocytic internalization is a common pathomechanisms in both experimental and human cholestasis; this results in bile secretory failure and, eventually, posttranslational transporter downregulation by increased degradation. This review summarizes the proposed structural mechanisms accounting for this pathological condition (e.g., alteration of function, localization or expression of F-actin or F-actin/transporter cross-linking proteins, and switch to membrane microdomains where they can be readily endocytosed), and the mediators implicated (e.g., triggering of “cholestatic” signaling transduction pathways). Lastly, we discussed the efficacy to counteract the cholestatic failure induced by transporter internalization of a number of therapeutic experimental approaches based upon the use of compounds that trigger exocytic targetting of canalicular transporters (e.g., cAMP, tauroursodeoxycholate). This therapeutics may complement treatments aimed to transcriptionally improve transporter expression, by affording proper localization and membrane stability to the de novo synthesized transporters.
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Affiliation(s)
- Marcelo G. Roma
- Instituto de Fisiologia Experimental (IFISE) - Facultad de Ciencias Bioquimicas y Farmaceuticas (CONICET - U.N.R.), S2002LRL, Rosario, Argentina
| | - Ismael R. Barosso
- Instituto de Fisiologia Experimental (IFISE) - Facultad de Ciencias Bioquimicas y Farmaceuticas (CONICET - U.N.R.), S2002LRL, Rosario, Argentina
| | - Gisel S. Miszczuk
- Instituto de Fisiologia Experimental (IFISE) - Facultad de Ciencias Bioquimicas y Farmaceuticas (CONICET - U.N.R.), S2002LRL, Rosario, Argentina
| | - Fernando A. Crocenzi
- Instituto de Fisiologia Experimental (IFISE) - Facultad de Ciencias Bioquimicas y Farmaceuticas (CONICET - U.N.R.), S2002LRL, Rosario, Argentina
| | - Enrique J. Sánchez Pozzi
- Instituto de Fisiologia Experimental (IFISE) - Facultad de Ciencias Bioquimicas y Farmaceuticas (CONICET - U.N.R.), S2002LRL, Rosario, Argentina
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21
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Zhang Y, Liu S, Feng Q, Huang X, Wang X, Peng Y, Zhao Z, Liu Z. Perilaldehyde activates AMP-activated protein kinase to suppress the growth of gastric cancer via induction of autophagy. J Cell Biochem 2019; 120:1716-1725. [PMID: 30378150 DOI: 10.1002/jcb.27491] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/18/2018] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND AIM Perillaldehyde (PAH), one of the major oil components in Perilla frutescens, is very critical to health maintenance, for a wide range of human chronic diseases, including cancers. AMP-activated protein kinase (AMPK) has been implicated in the activation of autophagy in distinct tissues. This study was designed to explore whether PAH prevents gastric cancer growth and to investigate the molecular mechanism. METHODS AND RESULTS In cultured mouse gastric cancer cell line MFCs and human gastric cancer cell lines GC9811-P, PAH activated AMPK by increasing the Thr172 phosphorylation and activity in a time-/concentration-dependent manner. Furthermore, incubation of MFCs with PAH also increased autophagy as determined by monodansylcadaverine (MDC) staining, which was reversed by AMPK inhibitor compound C. PAH further decreased MFCs cell survival, which was abolished by compound C or autophagy inhibitor 3-Methyladenine (3-MA). In vivo studies indicated that 4-week administration of PAH (100 mg/kg/day) suppressed the growth of gastric cancer and increased the levels of autophagy-related proteins, including beclin-1, LC3-II, cathepsin, caspase-3, p53, and cathepsin in tumors isolated from the xenograft model of gastric cancer in mice. Moreover, these anticancer effects produced by PAH were abolished by coadministration of compound C or 3-MA in vivo. CONCLUSIONS PAH increases AMPK phosphorylation and activity to induce gastric cancer cell autophagy to inhibit the growth of gastric cancer. In perspective, therapy of PAH should be applied to treat patients with gastric cancer.
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Affiliation(s)
- Yu Zhang
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Suosi Liu
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Qin Feng
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Xiuyun Huang
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Xiangyang Wang
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Ya Peng
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Zhihong Zhao
- Department of Neurology, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
| | - Zhan Liu
- Department of Gastroenterology and Clinical Nutrition, The First Affiliated Hospital (People's Hospital of Hunan Province), Hunan Normal University, Changsha, Hunan, China
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22
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Yao H, Fu X, Zi X, Jia W, Qiu Y. Perioperative oral supplementation with fish oil promotes liver regeneration following partial hepatectomy in mice via AMPK activation. Mol Med Rep 2017; 17:3905-3911. [PMID: 29286119 DOI: 10.3892/mmr.2017.8362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 09/20/2017] [Indexed: 11/05/2022] Open
Abstract
The present study aimed to observe the effects of perioperative oral supplementation with fish oil (FO) on liver regeneration in mice and examine the potential mechanism. A total of 120 male ICR mice were randomly divided into 5 groups: Sham, Control, fish oil (FO), Compound C [the AMP‑activated protein kinase (AMPK) inhibitor dorsomorphin], and Compound C + FO. Changes in liver function, alterations in hepatocyte proliferation and in the expression of polarization markers, and activation of AMPK signaling were examined following partial hepatectomy (PH). The results demonstrated that restoration of serum alanine aminotransferase (ALT) and total bilirubin (TBIL) levels were significantly faster in FO‑treated mice compared with Control mice, and this effect was suppressed by treatment with Compound C. FO‑treated mice exhibited increased numbers of Ki‑67 positive hepatocytes and their postoperative liver‑to‑body weight ratio was significantly increased compared with the Control mice, which was also suppressed by co‑treatment with the AMPK inhibitor. Furthermore, protein expression of Occludin, Claudin‑3, tight junction protein 1 and bile salt export pump was gradually increased in FO‑treated mice compared with Control, whereas Compound C treatment reversed this effect. Therefore, the present study revealed that perioperative oral supplementation with FO may promote liver regeneration and improved liver function in mice following PH through AMPK activation.
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Affiliation(s)
- Hui Yao
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210008, P.R. China
| | - Xiao Fu
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210008, P.R. China
| | - Xuejian Zi
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Clinical College of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Wenjun Jia
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210008, P.R. China
| | - Yudong Qiu
- Department of Hepatopancreatobiliary Surgery, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210008, P.R. China
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23
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Zhang C, Xiao X, Chen M, Aldharee H, Chen Y, Long W. Liver kinase B1 restoration promotes exosome secretion and motility of lung cancer cells. Oncol Rep 2017; 39:376-382. [PMID: 29138862 PMCID: PMC5783601 DOI: 10.3892/or.2017.6085] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 10/24/2017] [Indexed: 12/13/2022] Open
Abstract
Liver kinase B1 (LKB1) regulates a variety of cellular functions, including cell polarity, energy metabolism and cell growth, by targeting multiple signaling pathways such as AMPK/mTOR and p53. LKB1 functions as a tumor suppressor in sporadic cancers including lung cancer. Extracellular vesicles such as exosomes secreted by cancer cells modulate the tumor microenvironment and progression by targeting both tumor cells (autocrine actions) and other types of cells associated with tumors (paracrine actions). While the roles of LKB1 in cellular signaling in general is well-studied, its specific role in exosome-mediated signaling remains to be explored. To this purpose, we reintroduced LKB1 into H460 and A549 lung cancer cells that are endogenously deficient in LKB1 expression. Notably, we found that while restoration of LKB1 significantly reduced lung cancer cell growth as expected, it greatly promoted cell motility and enhanced the release of exosomes. In addition, exosomes isolated from H460 cells with stable restoration of LKB1 had much higher ability in stimulating lung cancer cell migration than did those from H460 cells lacking LKB1. Mechanistically, restoration of LKB1 in H460 cells inhibited cellular expression and exosomal secretion of migration-suppressing microRNAs (miRNAs), including miR-125a, miR-126 and let7b. Taken together, the present study revealed a new role for LKB1 in promoting cell motility by downregulating migration-suppressing miRNA expression and exosome secretion.
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Affiliation(s)
- Cheng Zhang
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Xiang Xiao
- Department of Pharmacology and Toxicology, Wright State University, Dayton, OH 45435, USA
| | - Minyi Chen
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Hitham Aldharee
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Yanfang Chen
- Department of Pharmacology and Toxicology, Wright State University, Dayton, OH 45435, USA
| | - Weiwen Long
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
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24
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Okamoto CT. Regulation of Transporters and Channels by Membrane-Trafficking Complexes in Epithelial Cells. Cold Spring Harb Perspect Biol 2017; 9:a027839. [PMID: 28246186 PMCID: PMC5666629 DOI: 10.1101/cshperspect.a027839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The vectorial secretion and absorption of fluid and solutes by epithelial cells is dependent on the polarized expression of membrane solute transporters and channels at the apical and basolateral membranes. The establishment and maintenance of this polarized expression of transporters and channels are affected by divers protein-trafficking complexes. Moreover, regulation of the magnitude of transport is often under control of physiological stimuli, again through the interaction of transporters and channels with protein-trafficking complexes. This review highlights the value in utilizing transporters and channels as cargo to characterize core trafficking machinery by which epithelial cells establish and maintain their polarized expression, and how this machinery regulates fluid and solute transport in response to physiological stimuli.
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Affiliation(s)
- Curtis T Okamoto
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089-9121
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25
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Li X, Liu R, Zhang L, Jiang Z. The emerging role of AMP-activated protein kinase in cholestatic liver diseases. Pharmacol Res 2017; 125:105-113. [PMID: 28889972 DOI: 10.1016/j.phrs.2017.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/15/2017] [Accepted: 09/05/2017] [Indexed: 11/26/2022]
Abstract
AMP-activated protein kinase (AMPK), recognized as an energy sensor with three heterotrimeric subunits (α, β and γ), not only maintains basal intracellular adenosine triphosphate levels but also regulates energy-intensive pathological responses, such as neurodegenerative and metabolic diseases, through multiple signaling pathways. Recent studies open a new direction for AMPK research and demonstrate that AMPK is a critical player in the pathogenesis of cholestatic liver injury and plays paradoxical roles in the regulation of different pathological processes, including the disruption of bile acid homeostasis and the regulation of hepatic polarity, inflammation and fibrosis. In the present review, we summarize recent findings that implicate AMPK-mediated signaling pathways in the pathogenesis of cholestatic liver injury. These findings provide novel insight regarding the potential use of AMPK as a therapeutic target for the treatment of cholestatic liver injury.
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Affiliation(s)
- Xiaojiaoyang Li
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China; Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Runping Liu
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Luyong Zhang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China; Center for Drug Screening and Pharmacodynamics Evaluation, School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zhenzhou Jiang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China; Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing, Jiangsu, China.
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26
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Scott Kiss R, Sniderman A. Shunts, channels and lipoprotein endosomal traffic: a new model of cholesterol homeostasis in the hepatocyte. J Biomed Res 2017; 31:95-107. [PMID: 28808191 PMCID: PMC5445212 DOI: 10.7555/jbr.31.20160139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The liver directs cholesterol metabolism in the organism. All the major fluxes of cholesterol within the body involve the liver: dietary cholesterol is directed to the liver; cholesterol from peripheral cells goes to the liver; the liver is a major site of cholesterol synthesis for the organism; cholesterol is secreted from the liver within the bile, within apoB lipoproteins and translocated to nascent HDL. The conventional model of cholesterol homeostasis posits that cholesterol from any source enters a common, rapidly exchangeable pool within the cell, which is in equilibrium with a regulatory pool. Increased influx of cholesterol leads rapidly to decreased synthesis of cholesterol. This model was developed based on in vitro studies in the fibroblast and validated only for LDL particles. The challenges the liver must meet in vivo to achieve cholesterol homeostasis are far more complex. Our model posits that the cholesterol derived from three different lipoproteins endosomes has three different fates: LDL-derived cholesterol is largely recycled within VLDL with most of the cholesterol shunted through the hepatocyte without entering the exchangeable pool of cholesterol; high density lipoprotein-derived CE is transcytosed into bile; and chylomicron remnant-derived cholesterol primarily enters the regulatory pool within the hepatocyte. These endosomal channels represent distinct physiological pathways and hepatic homeostasis represents the net result of the outcomes of these distinct channels. Our model takes into account the distinct physiological challenges the hepatocyte must meet, underlie the pathophysiology of many of the apoB dyslipoproteinemias and account for the sustained effectiveness of therapeutic agents such as statins.
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Affiliation(s)
- Robert Scott Kiss
- Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada.,Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Allan Sniderman
- Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada.,Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
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Deletion of Lkb1 in adult mice results in body weight reduction and lethality. Sci Rep 2016; 6:36561. [PMID: 27824128 PMCID: PMC5099919 DOI: 10.1038/srep36561] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/18/2016] [Indexed: 12/22/2022] Open
Abstract
Liver kinase B1 (Lkb1) plays crucial roles in development, metabolism and survival. As constitutive knockout of Lkb1 in mice leads to embryonic lethality, whether Lkb1 is required for the growth and survival of adult mice is unclear. Here we address this question using a tamoxifen-inducible Lkb1 knockout (KO) mouse model: Rosa26-CreER: Lkb1flox/flox (abbreviated as Rosa-Lkb1). The Rosa-Lkb1 mice exhibited body weight reduction and died within 6 weeks after tamoxifen induction. The body weight reduction was due to reduced weight of various tissues but the brown and white adipose tissues underwent much more pronounced weight reduction relative to the overall body weight reduction. Accordingly, the Rosa-Lkb1 mice had increased blood glucose levels and were intolerant to glucose challenge. Expression levels of adipogenic and lipogenic genes in adipose tissues were also dramatically reduced by Lkb1 deletion. Additionally, Lkb1 deletion reduced lipid deposition and increased expression of mitochondrial (Pgc1a, Cox5b and Cox7a) and hepatic gluconeogenesis related genes (Pepck) in liver. Finally, the Rosa-Lkb1 mice had much reduced oxygen consumption, carbon dioxide production, and energy expenditure. These results demonstrate that Lkb1 plays an important role in maintaining body weight, liver and adipose tissue function, blood glucose homeostasis and survival in adult mice.
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Porat‐Shliom N, Tietgens AJ, Van Itallie CM, Vitale‐Cross L, Jarnik M, Harding OJ, Anderson JM, Gutkind JS, Weigert R, Arias IM. Liver kinase B1 regulates hepatocellular tight junction distribution and function in vivo. Hepatology 2016; 64:1317-29. [PMID: 27396550 PMCID: PMC5033699 DOI: 10.1002/hep.28724] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/28/2016] [Accepted: 06/30/2016] [Indexed: 12/12/2022]
Abstract
UNLABELLED Liver kinase B1 (LKB1) and its downstream effector AMP-activated protein kinase (AMPK) play critical roles in polarity establishment by regulating membrane trafficking and energy metabolism. In collagen sandwich-cultured hepatocytes, loss of LKB1 or AMPK impaired apical ABCB11 (Bsep) trafficking and bile canalicular formation. In the present study, we used liver-specific (albumin-Cre) LKB1 knockout mice (LKB1(-/-) ) to investigate the role of LKB1 in the maintenance of functional tight junction (TJ) in vivo. Transmission electron microscopy examination revealed that hepatocyte apical membrane with microvilli substantially extended into the basolateral domain of LKB1(-/-) livers. Immunofluorescence studies revealed that loss of LKB1 led to longer and wider canalicular structures correlating with mislocalization of the junctional protein, cingulin. To test junctional function, we used intravital microscopy to quantify the transport kinetics of 6-carboxyfluorescein diacetate (6-CFDA), which is processed in hepatocytes into its fluorescent derivative 6-carboxyfluorescein (6-CF) and secreted into the canaliculi. In LKB1(-/-) mice, 6-CF remained largely in hepatocytes, canalicular secretion was delayed, and 6-CF appeared in the blood. To test whether 6-CF was transported through permeable TJ, we intravenously injected low molecular weight (3 kDa) dextran in combination with 6-CFDA. In wild-type mice, 3 kDa dextran remained in the vasculature, whereas it rapidly appeared in the abnormal bile canaliculi in LKB1(-/-) mice, confirming that junctional disruption resulted in paracellular exchange between the blood stream and the bile canaliculus. CONCLUSION LKB1 plays a critical role in regulating the maintenance of TJ and paracellular permeability, which may explain how various drugs, chemicals, and metabolic states that inhibit the LKB1/AMPK pathway result in cholestasis. (Hepatology 2016;64:1317-1329).
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Affiliation(s)
- Natalie Porat‐Shliom
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMD,Laboratory of Cellular and Molecular Biology, National Cancer InstituteNational Institutes of HealthBethesdaMD
| | - Amber J. Tietgens
- Laboratory of Tight Junction Structure and FunctionNational Heart, Lung, and Blood InstituteBethesdaMD
| | - Christina M. Van Itallie
- Laboratory of Tight Junction Structure and FunctionNational Heart, Lung, and Blood InstituteBethesdaMD
| | - Lynn Vitale‐Cross
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMD
| | - Michal Jarnik
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMD
| | - Olivia J. Harding
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMD
| | - James M. Anderson
- Laboratory of Tight Junction Structure and FunctionNational Heart, Lung, and Blood InstituteBethesdaMD
| | - J. Silvio Gutkind
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMD,Present address: University of California, San Diego, Moores Cancer CenterLa JollaCA92093
| | - Roberto Weigert
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMD,Laboratory of Cellular and Molecular Biology, National Cancer InstituteNational Institutes of HealthBethesdaMD
| | - Irwin M. Arias
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMD
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Sharanek A, Burban A, Burbank M, Le Guevel R, Li R, Guillouzo A, Guguen-Guillouzo C. Rho-kinase/myosin light chain kinase pathway plays a key role in the impairment of bile canaliculi dynamics induced by cholestatic drugs. Sci Rep 2016; 6:24709. [PMID: 27169750 PMCID: PMC4867683 DOI: 10.1038/srep24709] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 04/01/2016] [Indexed: 01/12/2023] Open
Abstract
Intrahepatic cholestasis represents a frequent manifestation of drug-induced liver injury; however, the mechanisms underlying such injuries are poorly understood. In this study of human HepaRG and primary hepatocytes, we found that bile canaliculi (BC) underwent spontaneous contractions, which are essential for bile acid (BA) efflux and require alternations in myosin light chain (MLC2) phosphorylation/dephosphorylation. Short exposure to 6 cholestatic compounds revealed that BC constriction and dilation were associated with disruptions in the ROCK/MLCK/myosin pathway. At the studied concentrations, cyclosporine A and chlorpromazine induced early ROCK activity, resulting in permanent MLC2 phosphorylation and BC constriction. However, fasudil reduced ROCK activity and caused rapid, substantial and permanent MLC2 dephosphorylation, leading to BC dilation. The remaining compounds (1-naphthyl isothiocyanate, deoxycholic acid and bosentan) caused BC dilation without modulating ROCK activity, although they were associated with a steady decrease in MLC2 phosphorylation via MLCK. These changes were associated with a common loss of BC contractions and failure of BA clearance. These results provide the first demonstration that cholestatic drugs alter BC dynamics by targeting the ROCK/MLCK pathway; in addition, they highlight new insights into the mechanisms underlying bile flow failure and can be used to identify new predictive biomarkers of drug-induced cholestasis.
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Affiliation(s)
- Ahmad Sharanek
- INSERM U991, Liver Metabolisms and Cancer, Rennes, France.,Rennes 1 University, Rennes, France
| | - Audrey Burban
- INSERM U991, Liver Metabolisms and Cancer, Rennes, France.,Rennes 1 University, Rennes, France
| | - Matthew Burbank
- INSERM U991, Liver Metabolisms and Cancer, Rennes, France.,Rennes 1 University, Rennes, France
| | - Rémy Le Guevel
- ImPACcell platform, Biosit, Rennes 1 University, Rennes, France
| | - Ruoya Li
- Biopredic International, St Grégoire, France
| | - André Guillouzo
- INSERM U991, Liver Metabolisms and Cancer, Rennes, France.,Rennes 1 University, Rennes, France
| | - Christiane Guguen-Guillouzo
- INSERM U991, Liver Metabolisms and Cancer, Rennes, France.,Rennes 1 University, Rennes, France.,Biopredic International, St Grégoire, France
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Hu M, Liu B. Resveratrol via activation of LKB1-AMPK signaling suppresses oxidative stress to prevent endothelial dysfunction in diabetic mice. Clin Exp Hypertens 2016; 38:381-7. [PMID: 27149559 DOI: 10.3109/10641963.2015.1131288] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Resveratrol, a phytoalexin, is reported to activate AMP-activated protein kinase (AMPK) in vascular cells. Whether resveratrol via activation of AMPK improves endothelial dysfunction in diabetes remains unknown. Here, we reported that activation of AMPK is required for resveratrol-induced improvement of endothelial function in diabetic mice. METHODS AMPK phosphorylation and activity, productions of reactive oxygen species, endothelium-dependent/independent relaxation were determined in vitro or in vivo. RESULTS Exposure of cultured human umbilical vein endothelial cells (HUVECs) to resveratrol activates AMPK by increasing the thr172 phosphorylation and its activities in time/dose-dependent manner. Loss function of liver kinase B1 by siRNA or mutant abolished resveratrol-induced AMPK activation. Incubation of endothelial cells with high glucose (HG) markedly induced oxidative stress of HUVECs, which was abolished by resveratrol in AMPK-dependent manner. In isolated mice aortas, resveratrol, AICAR or apocynin improved endothelium-dependent relaxation impaired by HG. In animal studies, streptozotocin-induced hyperglycemia dramatically increased oxidative stress and caused endothelial dysfunction, which were reversed by administration of resveratrol. CONCLUSIONS We conclude that AMPK activation is required for resveratrol to improve endothelial function in diabetic mice.
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Affiliation(s)
- Min Hu
- a Department of Biomedical Engineering , College of Engineering, Peking University , Beijing , China
| | - Bo Liu
- b Department of Orthopaedics , The Third Xiangya Hospital, Central South University , Changsha , China
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31
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Salas PJ, Forteza R, Mashukova A. Multiple roles for keratin intermediate filaments in the regulation of epithelial barrier function and apico-basal polarity. Tissue Barriers 2016; 4:e1178368. [PMID: 27583190 PMCID: PMC4993576 DOI: 10.1080/21688370.2016.1178368] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/05/2016] [Accepted: 04/07/2016] [Indexed: 12/27/2022] Open
Abstract
As multicellular organisms evolved a family of cytoskeletal proteins, the keratins (types I and II) expressed in epithelial cells diversified in more than 20 genes in vertebrates. There is no question that keratin filaments confer mechanical stiffness to cells. However, such a number of genes can hardly be explained by evolutionary advantages in mechanical features. The use of transgenic mouse models has revealed unexpected functional relationships between keratin intermediate filaments and intracellular signaling. Accordingly, loss of keratins or mutations in keratins that cause or predispose to human diseases, result in increased sensitivity to apoptosis, regulation of innate immunity, permeabilization of tight junctions, and mistargeting of apical proteins in different epithelia. Precise mechanistic explanations for these phenomena are still lacking. However, immobilization of membrane or cytoplasmic proteins, including chaperones, on intermediate filaments (“scaffolding”) appear as common molecular mechanisms and may explain the need for so many different keratin genes in vertebrates.
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Affiliation(s)
- Pedro J Salas
- Department of Cell Biology, Miller School of Medicine, University of Miami , Miami, FL, USA
| | - Radia Forteza
- Department of Cell Biology, Miller School of Medicine, University of Miami , Miami, FL, USA
| | - Anastasia Mashukova
- Department of Cell Biology, Miller School of Medicine, University of Miami, Miami, FL, USA; Department of Physiology, Nova Southeastern University, Fort Lauderdale, FL, USA
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32
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Li X, Liu R, Luo L, Yu L, Chen X, Sun L, Wang T, Hylemon PB, Zhou H, Jiang Z, Zhang L. Role of AMP-activated protein kinase α1 in 17α-ethinylestradiol-induced cholestasis in rats. Arch Toxicol 2016; 91:481-494. [PMID: 27090119 DOI: 10.1007/s00204-016-1697-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 03/21/2016] [Indexed: 12/12/2022]
Abstract
Estrogen-induced cholestasis occurs in many women who are susceptible due to pregnancy or hormone replacement therapy for postmenopausal syndrome. 17α-Ethinylestradiol (EE), as a synthetic estrogen, has been widely used to study the underlying mechanisms of estrogen-induced cholestasis. Recent studies have also reported that liver kinase B1 (LKB1)-mediated activation of AMP-activated protein kinase (AMPK) plays a critical role in the regulation of canalicular network formation. However, the role of AMPK in EE-induced cholestasis remains to be determined. In this study, the effects of EE (1-100 µM) on AMPK activation and the expression of farnesoid X receptor (FXR) and hepatic bile acid transporters were examined in in vitro using 3D-cultured rat primary hepatocytes and in in vivo using rat cholestasis models. We also used specific chemical agonist and antagonist of AMPK, AMPK subunit-specific antibodies and lentiviral shRNAs for AMPKα1 and AMPKα2 to delineate the role of AMPK in EE-induced cholestasis and potential cellular mechanisms. We found that EE-induced phosphorylation of AMPKα1 via extracellular signal-regulated kinases-LKB1-mediated signaling pathways and subsequent nuclear translocation accounted for the down-regulation of FXR and bile acid transporters and disruption of bile acid homeostasis. Inhibition of AMPK activation using an AMPK antagonist Compound C (2 µM) or down-regulation of AMPKα1 using gene-specific shRNA attenuated EE-induced cholestasis both in in vitro and in in vivo. In conclusion, these results revealed that activation of cAMP-ERK-LKB1-AMPKα1 signaling pathway plays a critical role in EE-mediated dysregulation of the expression of FXR and bile acid transporters. AMPKα1 may represent an important therapeutic target for estrogen-induced cholestasis.
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Affiliation(s)
- Xiaojiaoyang Li
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.,Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Runping Liu
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.,Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Lan Luo
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Linxi Yu
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Xin Chen
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Lixin Sun
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Tao Wang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.,Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Phillip B Hylemon
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, 23298, USA.,McGuire Veterans Affairs Medical Center, Richmond, VA, 23249, USA
| | - Huiping Zhou
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, 23298, USA. .,McGuire Veterans Affairs Medical Center, Richmond, VA, 23249, USA.
| | - Zhenzhou Jiang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China. .,Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.
| | - Luyong Zhang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China. .,Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.
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Telbisz Á, Homolya L. Recent advances in the exploration of the bile salt export pump (BSEP/ABCB11) function. Expert Opin Ther Targets 2015; 20:501-14. [PMID: 26573700 DOI: 10.1517/14728222.2016.1102889] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The bile salt export pump (BSEP/ABCB11), residing in the apical membrane of hepatocyte, mediates the secretion of bile salts into the bile. A range of human diseases is associated with the malfunction of BSEP, including fatal hereditary liver disorders and mild cholestatic conditions. Manifestation of these diseases primarily depends on the mutation type; however, other factors such as hormonal changes and drug interactions can also trigger or influence the related diseases. AREAS COVERED Here, we summarize the recent knowledge on BSEP by covering its transport properties, cellular localization, regulation and major mutations/polymorphisms, as well as the hereditary and acquired diseases associated with BSEP dysfunction. We discuss the different model expression systems employed to understand the function of the BSEP variants, their drug interactions and the contemporary therapeutic interventions. EXPERT OPINION The limitations of the available model expression systems for BSEP result in controversial conclusions, and obstruct our deeper insight into BSEP deficiencies and BSEP-related drug interactions. The knowledge originating from different methodologies, such as clinical studies, molecular genetics, as well as in vitro and in silico modeling, should be integrated and harmonized. Increasing availability of robust molecular biological tools and our better understanding of the mechanism of BSEP deficiencies should make the personalized, mutation-based therapeutic interventions more attainable.
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Affiliation(s)
- Ágnes Telbisz
- a Institute of Enzymology, Research Centre for Natural Sciences , Hungarian Academy of Sciences , Magyar tudósok körútja 2, Budapest 1117 , Hungary
| | - László Homolya
- a Institute of Enzymology, Research Centre for Natural Sciences , Hungarian Academy of Sciences , Magyar tudósok körútja 2, Budapest 1117 , Hungary
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Gissen P, Arias IM. Structural and functional hepatocyte polarity and liver disease. J Hepatol 2015; 63:1023-37. [PMID: 26116792 PMCID: PMC4582071 DOI: 10.1016/j.jhep.2015.06.015] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 06/14/2015] [Accepted: 06/15/2015] [Indexed: 02/08/2023]
Abstract
Hepatocytes form a crucially important cell layer that separates sinusoidal blood from the canalicular bile. They have a uniquely organized polarity with a basal membrane facing liver sinusoidal endothelial cells, while one or more apical poles can contribute to several bile canaliculi jointly with the directly opposing hepatocytes. Establishment and maintenance of hepatocyte polarity is essential for many functions of hepatocytes and requires carefully orchestrated cooperation between cell adhesion molecules, cell junctions, cytoskeleton, extracellular matrix and intracellular trafficking machinery. The process of hepatocyte polarization requires energy and, if abnormal, may result in severe liver disease. A number of inherited disorders affecting tight junction and intracellular trafficking proteins have been described and demonstrate clinical and pathophysiological features overlapping those of the genetic cholestatic liver diseases caused by defects in canalicular ABC transporters. Thus both structural and functional components contribute to the final hepatocyte polarity phenotype. Many acquired liver diseases target factors that determine hepatocyte polarity, such as junctional proteins. Hepatocyte depolarization frequently occurs but is rarely recognized because hematoxylin-eosin staining does not identify the bile canaliculus. However, the molecular mechanisms underlying these defects are not well understood. Here we aim to provide an update on the key factors determining hepatocyte polarity and how it is affected in inherited and acquired diseases.
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Affiliation(s)
- Paul Gissen
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; UCL Institute of Child Health, London, UK; Great Ormond Street Hospital, London, UK.
| | - Irwin M Arias
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States
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35
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Overeem AW, Bryant DM, van IJzendoorn SC. Mechanisms of apical–basal axis orientation and epithelial lumen positioning. Trends Cell Biol 2015; 25:476-85. [DOI: 10.1016/j.tcb.2015.04.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/24/2015] [Accepted: 04/06/2015] [Indexed: 12/17/2022]
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36
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Zhao L, Sun LN, Nie HB, Wang XL, Guan GJ. Berberine improves kidney function in diabetic mice via AMPK activation. PLoS One 2014; 9:e113398. [PMID: 25409232 PMCID: PMC4237447 DOI: 10.1371/journal.pone.0113398] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 10/23/2014] [Indexed: 11/18/2022] Open
Abstract
Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. Effective therapies to prevent the development of this disease are required. Berberine (BBR) has several preventive effects on diabetes and its complications. However, the molecular mechanism of BBR on kidney function in diabetes is not well defined. Here, we reported that activation of AMP-activated protein kinase (AMPK) is required for BBR-induced improvement of kidney function in vivo. AMPK phosphorylation and activity, productions of reactive oxygen species (ROS), kidney function including serum blood urea nitrogen (BUN), creatinine clearance (Ccr), and urinary protein excretion, morphology of glomerulus were determined in vitro or in vivo. Exposure of cultured human glomerulus mesangial cells (HGMCs) to BBR time- or dose-dependently activates AMPK by increasing the thr172 phosphorylation and its activities. Inhibition of LKB1 by siRNA or mutant abolished BBR-induced AMPK activation. Incubation of cells with high glucose (HG, 30 mM) markedly induced the oxidative stress of HGMCs, which were abolished by 5-aminoimidazole-4-carboxamide ribonucleoside, AMPK gene overexpression or BBR. Importantly, the effects induced by BBR were bypassed by AMPK siRNA transfection in HG-treated HGMCs. In animal studies, streptozotocin-induced hyperglycemia dramatically promoted glomerulosclerosis and impaired kidney function by increasing serum BUN, urinary protein excretion, and decreasing Ccr, as well as increased oxidative stress. Administration of BBR remarkably improved kidney function in wildtype mice but not in AMPKα2-deficient mice. We conclude that AMPK activation is required for BBR to improve kidney function in diabetic mice.
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Affiliation(s)
- Long Zhao
- Nephrology Research Institute, the Second Hospital of Shandong University, Jinan, Shandong, China
| | - Li-Na Sun
- Nephrology Research Institute, the Second Hospital of Shandong University, Jinan, Shandong, China
| | - Hui-Bin Nie
- Nephrology Research Institute, the Second Hospital of Shandong University, Jinan, Shandong, China
| | - Xue-Ling Wang
- Nephrology Research Institute, the Second Hospital of Shandong University, Jinan, Shandong, China
| | - Guang-Ju Guan
- Nephrology Research Institute, the Second Hospital of Shandong University, Jinan, Shandong, China
- * E-mail:
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Gökirmak T, Shipp LE, Campanale JP, Nicklisch SCT, Hamdoun A. Transport in technicolor: mapping ATP-binding cassette transporters in sea urchin embryos. Mol Reprod Dev 2014; 81:778-93. [PMID: 25156004 DOI: 10.1002/mrd.22357] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 06/27/2014] [Indexed: 12/15/2022]
Abstract
One quarter of eukaryotic genes encode membrane proteins. These include nearly 1,000 transporters that translocate nutrients, signaling molecules, and xenobiotics across membranes. While it is well appreciated that membrane transport is critical for development, the specific roles of many transporters have remained cryptic, in part because of their abundance and the diversity of their substrates. Multidrug resistance ATP-binding cassette (ABC) efflux transporters are one example of cryptic membrane proteins. Although most organisms utilize these ABC transporters during embryonic development, many of these transporters have broad substrate specificity, and their developmental functions remain incompletely understood. Here, we review advances in our understanding of ABC transporters in sea urchin embryos, and methods developed to spatially and temporally map these proteins. These studies reveal that multifunctional transporters are required for signaling, homeostasis, and protection of the embryo, and shed light on how they are integrated into ancestral developmental pathways recapitulated in disease.
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Affiliation(s)
- Tufan Gökirmak
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California
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Müsch A. The unique polarity phenotype of hepatocytes. Exp Cell Res 2014; 328:276-83. [PMID: 24956563 DOI: 10.1016/j.yexcr.2014.06.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 01/11/2023]
Abstract
Hepatocytes, the main epithelial cell type of the liver, function like all epithelial cells to mediate the vectorial flow of macromolecules into and out of the organ they encompass. They do so by establishing polarized surface domains and by restricting paracellular flow via their tight junctions and cell-cell adhesion. Yet, the cell and tissue organization of hepatocytes differs profoundly from that of most other epithelia, including those of the digestive and urinary tracts, the lung or the breast. The latter form monolayered tissues in which the apical domains of individual cells align around a central continuous luminal cavity that constitutes the tubules and acini characteristic of these organs. Hepatocytes, by contrast, form capillary-sized lumina with multiple neighbors resulting in a branched, tree-like bile canaliculi network that spreads across the liver parenchyme. I will discuss some of the key molecular features that distinguish the hepatocyte polarity phenotype from that of monopolar, columnar epithelia.
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Affiliation(s)
- Anne Müsch
- Albert-Einstein College of Medicine, Department of Cell & Molecular Biology, The Bronx, USA.
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