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Haaker MW, Goossens V, Hoogland NAN, van Doorne H, Wang Z, Jansen JWA, Kaloyanova DV, van de Lest CHA, Houweling M, Vaandrager AB, Helms JB. Early activation of hepatic stellate cells induces rapid initiation of retinyl ester breakdown while maintaining lecithin:retinol acyltransferase (LRAT) activity. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159540. [PMID: 39068984 DOI: 10.1016/j.bbalip.2024.159540] [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] [Received: 12/21/2023] [Revised: 06/30/2024] [Accepted: 07/25/2024] [Indexed: 07/30/2024]
Abstract
Lecithin:retinol acyltransferase (LRAT) is the main enzyme producing retinyl esters (REs) in quiescent hepatic stellate cells (HSCs). When cultured on stiff plastic culture plates, quiescent HSCs activate and lose their RE stores in a process similar to that in the liver following tissue damage, leading to fibrosis. Here we validated HSC cultures in soft gels to study RE metabolism in stable quiescent HSCs and investigated RE synthesis and breakdown in activating HSCs. HSCs cultured in a soft gel maintained characteristics of quiescent HSCs, including the size, amount and composition of their characteristic large lipid droplets. Quiescent gel-cultured HSCs maintained high expression levels of Lrat and a RE storing phenotype with low levels of RE breakdown. Newly formed REs are highly enriched in retinyl palmitate (RP), similar to freshly isolated quiescent HSCs, which is associated with high LRAT activity. Comparison of these quiescent gel-cultured HSCs with activated plastic-cultured HSCs showed that although during early activation the total RE levels and RP-enrichment are reduced, levels of RE formation are maintained and mediated by LRAT. Loss of REs was caused by enhanced RE breakdown in activating HSCs. Upon prolonged culturing, activated HSCs have lost their LRAT activity and produce small amounts of REs by DGAT1. This study reveals unexpected dynamics in RE metabolism during early HSC activation, which might be important in liver disease as early stages are reversible. Soft gel cultures provide a promising model to study RE metabolism in quiescent HSCs, allowing detailed molecular investigations on the mechanisms for storage and release.
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Affiliation(s)
- Maya W Haaker
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Vera Goossens
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Nina A N Hoogland
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Hidde van Doorne
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Ziqiong Wang
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Jeroen W A Jansen
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Dora V Kaloyanova
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Chris H A van de Lest
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - Martin Houweling
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - A Bas Vaandrager
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - J Bernd Helms
- Department of Biomolecular Health Sciences, Division of Cell Biology, Metabolism & Cancer, Faculty of Veterinary Medicine and Institute of Biomembranes, Utrecht University, 3584 CM Utrecht, the Netherlands.
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2
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Wang S, Link F, Munker S, Wang W, Feng R, Liebe R, Li Y, Yao Y, Liu H, Shao C, Ebert MP, Ding H, Dooley S, Weng HL, Wang SS. Retinoic acid generates a beneficial microenvironment for liver progenitor cell activation in acute liver failure. Hepatol Commun 2024; 8:e0483. [PMID: 39023343 PMCID: PMC11262820 DOI: 10.1097/hc9.0000000000000483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 04/05/2024] [Indexed: 07/20/2024] Open
Abstract
BACKGROUND When massive necrosis occurs in acute liver failure (ALF), rapid expansion of HSCs called liver progenitor cells (LPCs) in a process called ductular reaction is required for survival. The underlying mechanisms governing this process are not entirely known to date. In ALF, high levels of retinoic acid (RA), a molecule known for its pleiotropic roles in embryonic development, are secreted by activated HSCs. We hypothesized that RA plays a key role in ductular reaction during ALF. METHODS RNAseq was performed to identify molecular signaling pathways affected by all-trans retinoid acid (atRA) treatment in HepaRG LPCs. Functional assays were performed in HepaRG cells treated with atRA or cocultured with LX-2 cells and in the liver tissue of patients suffering from ALF. RESULTS Under ALF conditions, activated HSCs secreted RA, inducing RARα nuclear translocation in LPCs. RNAseq data and investigations in HepaRG cells revealed that atRA treatment activated the WNT-β-Catenin pathway, enhanced stemness genes (SOX9, AFP, and others), increased energy storage, and elevated the expression of ATP-binding cassette transporters in a RARα nuclear translocation-dependent manner. Further, atRA treatment-induced pathways were confirmed in a coculture system of HepaRG with LX-2 cells. Patients suffering from ALF who displayed RARα nuclear translocation in the LPCs had significantly better MELD scores than those without. CONCLUSIONS During ALF, RA secreted by activated HSCs promotes LPC activation, a prerequisite for subsequent LPC-mediated liver regeneration.
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Affiliation(s)
- Sai Wang
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Frederik Link
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan Munker
- Department of Medicine II, University Hospital, LMU Munich, Munich, Germany
- Liver Center Munich, University Hospital, LMU, Munich, Germany
| | - Wenjing Wang
- Beijing Institute of Hepatology, Beijing You’an Hospital, Capital Medical University, Beijing, China
| | - Rilu Feng
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Endocrinology and Metabolism, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Roman Liebe
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke-University, Magdeburg, Germany
| | - Yujia Li
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Ye Yao
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Hui Liu
- Department of Pathology, Beijing You’an Hospital, Affiliated with Capital Medical University, Beijing, China
| | - Chen Shao
- Department of Pathology, Beijing You’an Hospital, Affiliated with Capital Medical University, Beijing, China
| | - Matthias P.A. Ebert
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Molecular Medicine Partnership Unit, European Molecular Biology Laboratory, Heidelberg, Germany
- DKFZ-Hector Cancer Institute at the University Medical Center, Mannheim, Germany
| | - Huiguo Ding
- Department of Gastroenterology and Hepatology, Beijing You’an Hospital, Affiliated with Capital Medical University, Beijing, China
| | - Steven Dooley
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Hong-Lei Weng
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Shan-Shan Wang
- Beijing Institute of Hepatology, Beijing You’an Hospital, Capital Medical University, Beijing, China
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3
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Abstract
Introduction: Hepatic stellate cells (HSCs) are essential for physiological homeostasis of the liver extracellular matrix (ECM). Excessive transdifferentiation of HSC from a quiescent to an activated phenotype contributes to disrupt this balance and can lead to liver fibrosis. Accumulating evidence has suggested that nuclear receptors (NRs) are involved in the regulation of HSC activation, proliferation, and function. Therefore, these NRs may be therapeutic targets to balance ECM homeostasis and inhibit HSC activation in liver fibrosis.Areas covered: In this review, the authors summarized the recent progress in the understanding of the regulatory role of NRs in HSCs and their potential as drug targets in liver fibrosis.Expert opinion: NRs are still potential therapy targets for inhibiting HSCs activation and liver fibrosis. However, the development of NRs agonists or antagonists to inhibit HSCs requires fully consideration of systemic effects.
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Affiliation(s)
- Shiyun Pu
- Department of Pharmacy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
| | - Hongjing Zhou
- Department of Pharmacy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
| | - Yan Liu
- Department of Interventional Therapy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
| | - Jiao Liu
- Department of Interventional Therapy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
- Department of Hepatobiliary Surgery, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
| | - Yuanxin Guo
- Department of Pharmacy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
| | - Houfeng Zhou
- Department of Pharmacy, Chengdu Fifth People's Hospital, Chengdu University of TCM, Chengdu, China
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Li B, Cai SY, Boyer JL. The role of the retinoid receptor, RAR/RXR heterodimer, in liver physiology. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166085. [PMID: 33497820 PMCID: PMC11152086 DOI: 10.1016/j.bbadis.2021.166085] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/09/2021] [Accepted: 01/12/2021] [Indexed: 12/31/2022]
Abstract
Activated by retinoids, metabolites of vitamin A, the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs) play important roles in a wide variety of biological processes, including embryo development, homeostasis, cell proliferation, differentiation and death. In this review, we summarized the functional roles of nuclear receptor RAR/RXR heterodimers in liver physiology. Specifically, RAR/RXR modulate the synthesis and metabolism of lipids and bile acids in hepatocytes, regulate cholesterol transport in macrophages, and repress fibrogenesis in hepatic stellate cells. We have also listed the specific genes that carry these functions and how RAR/RXR regulate their expression in liver cells, providing a mechanistic view of their roles in liver physiology. Meanwhile, we pointed out many questions regarding the detailed signaling of RAR/RXR in regulating the expression of liver genes, and hope future studies will address these issues.
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Affiliation(s)
- Baixue Li
- Liver Center, Yale University School of Medicine, New Haven, CT 06520, United States; College of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
| | - Shi-Ying Cai
- Liver Center, Yale University School of Medicine, New Haven, CT 06520, United States.
| | - James L Boyer
- Liver Center, Yale University School of Medicine, New Haven, CT 06520, United States.
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5
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The stellate cell system (vitamin A-storing cell system). Anat Sci Int 2017; 92:387-455. [PMID: 28299597 DOI: 10.1007/s12565-017-0395-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/15/2017] [Indexed: 01/18/2023]
Abstract
Past, present, and future research into hepatic stellate cells (HSCs, also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells, or Ito cells) are summarized and discussed in this review. Kupffer discovered black-stained cells in the liver using the gold chloride method and named them stellate cells (Sternzellen in German) in 1876. Wake rediscovered the cells in 1971 using the same gold chloride method and various modern histological techniques including electron microscopy. Between their discovery and rediscovery, HSCs disappeared from the research history. Their identification, the establishment of cell isolation and culture methods, and the development of cellular and molecular biological techniques promoted HSC research after their rediscovery. In mammals, HSCs exist in the space between liver parenchymal cells (PCs) or hepatocytes and liver sinusoidal endothelial cells (LSECs) of the hepatic lobule, and store 50-80% of all vitamin A in the body as retinyl ester in lipid droplets in the cytoplasm. SCs also exist in extrahepatic organs such as pancreas, lung, and kidney. Hepatic (HSCs) and extrahepatic stellate cells (EHSCs) form the stellate cell (SC) system or SC family; the main storage site of vitamin A in the body is HSCs in the liver. In pathological conditions such as liver fibrosis, HSCs lose vitamin A, and synthesize a large amount of extracellular matrix (ECM) components including collagen, proteoglycan, glycosaminoglycan, and adhesive glycoproteins. The morphology of these cells also changes from the star-shaped HSCs to that of fibroblasts or myofibroblasts.
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6
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Panebianco C, Oben JA, Vinciguerra M, Pazienza V. Senescence in hepatic stellate cells as a mechanism of liver fibrosis reversal: a putative synergy between retinoic acid and PPAR-gamma signalings. Clin Exp Med 2016; 17:269-280. [PMID: 27655446 DOI: 10.1007/s10238-016-0438-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 09/08/2016] [Indexed: 12/16/2022]
Abstract
Hepatic stellate cells (HSCs), also known as perisinusoidal cells, are pericytes found in the perisinusoidal space of the liver. HSCs are the major cell type involved in liver fibrosis, which is the formation of scar tissue in response to liver damage. When the liver is damaged, stellate cells can shift into an activated state, characterized by proliferation, contractility and chemotaxis. The activated HSCs secrete collagen scar tissue, which can lead to cirrhosis. Recent studies have shown that in vivo activation of HSCs by fibrogenic agents can eventually lead to senescence of these cells, which would contribute to reversal of fibrosis although it may also favor the insurgence of liver cancer. HSCs in their non-active form store huge amounts of retinoic acid derivatives in lipid droplets, which are progressively depleted upon cell activation in injured liver. Retinoic acid is a metabolite of vitamin A (retinol) that mediates the functions of vitamin A, generally required for growth and development. The precise function of retinoic acid and its alterations in HSCs has yet to be elucidated, and nonetheless in various cell types retinoic acid and its receptors (RAR and RXR) are known to act synergistically with peroxisome proliferator-activated receptor gamma (PPAR-gamma) signaling through the activity of transcriptional heterodimers. Here, we review the recent advancements in the understanding of how retinoic acid signaling modulates the fibrogenic potential of HSCs and proposes a synergistic combined action with PPAR-gamma in the reversal of liver fibrosis.
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Affiliation(s)
- Concetta Panebianco
- Gastroenterology Unit, IRCCS "Casa Sollievo della Sofferenza" Hospital, Viale dei Cappuccini, 1, San Giovanni Rotondo, FG, Italy
| | - Jude A Oben
- Institute for Liver and Digestive Health, Royal Free Hospital, University College London (UCL), London, UK
| | - Manlio Vinciguerra
- Institute for Liver and Digestive Health, Royal Free Hospital, University College London (UCL), London, UK.,Center for Translational Medicine (CTM), International Clinical Research Center (ICRC), St. Anne's University Hospital, Brno, Czech Republic.,Centro Studi Fegato (CSF)-Liver Research Center, Fondazione Italiana Fegato, Trieste, Italy
| | - Valerio Pazienza
- Gastroenterology Unit, IRCCS "Casa Sollievo della Sofferenza" Hospital, Viale dei Cappuccini, 1, San Giovanni Rotondo, FG, Italy.
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7
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Elsayed AM, Abdelghany TM, Akool ES, Abdel-Aziz AAH, Abdel-Bakky MS. All-trans retinoic acid potentiates cisplatin-induced kidney injury in rats: impact of retinoic acid signaling pathway. Naunyn Schmiedebergs Arch Pharmacol 2015; 389:327-37. [PMID: 26659823 DOI: 10.1007/s00210-015-1193-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 11/15/2015] [Indexed: 12/18/2022]
Abstract
Cisplatin (cis-diammine dichloroplatinum (II), CDDP) is a widely used drug for treatment of various types of cancers. However, CDDP-induced nephrotoxicity remains the main dose-limiting side effect. Retinoids are a group of vitamin A-related compounds that exert their effects through retinoid receptors activation. In this study, we investigated the effect of CDDP treatment on retinoic acid receptor-α (RAR-α) and retinoid X receptor-α (RXR-α) expression. In addition, we investigated the possible modulatory effects of RAR agonist, all-trans retinoic acid (ATRA), on CDDP-induced nephrotoxicity. Rats were treated with saline, DMSO, CDDP, ATRA, or CDDP/ATRA. Twenty-four hours after the last ATRA injection, rats were killed; blood samples were collected; kidneys were dissected; and biochemical, immunohistochemical, and histological examinations were performed. Our results revealed that CDDP treatment significantly increased serum levels of creatinine and urea, with concomitant decrease in serum albumin. Moreover, reduced glutathione (GSH) content as well as superoxide dismutase (SOD) and catalase (CAT) activities were significantly reduced with concurrent increase in kidney malondialdehyde (MDA) content following CDDP treatment. Furthermore, CDDP markedly upregulated tubular RAR-α, RXR-α, fibrin, and inducible nitric oxide synthase (iNOS) protein expression. Although administration of ATRA to control rats did not produce marked alterations in kidney function parameters, administration of ATRA to CDDP-treated rats significantly exacerbated CDDP-induced nephrotoxicity. In addition, CDDP/ATRA co-treatment significantly increased RAR-α, RXR-α, fibrin, and iNOS protein expression compared to CDDP alone. In conclusion, we report, for the first time, the crucial role of retinoid receptors in CDDP-induced nephrotoxicity. Moreover, our findings indicate that co-administration of ATRA with CDDP, although beneficial on the therapeutic effects, their deleterious effects on the kidney may limit their clinical use.
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Affiliation(s)
| | | | | | | | - Mohamed S Abdel-Bakky
- Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.,College of Pharmacy, Aljouf University, Sakaka, Aljouf, 2014, Kingdom of Saudi Arabia
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8
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All-trans retinoic acid mitigates methotrexate-induced liver injury in rats; relevance of retinoic acid signaling pathway. Naunyn Schmiedebergs Arch Pharmacol 2015; 388:931-8. [PMID: 25971792 DOI: 10.1007/s00210-015-1130-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Accepted: 05/03/2015] [Indexed: 02/01/2023]
Abstract
Methotrexate (MTX) is a widely used drug for treatment of rheumatic and autoimmune diseases as well as different types of cancer. One of the major side effects of MTX is hepatotoxicity. Retinoid receptors, including retinoid X receptor (RXR), and retinoic acid receptor (RAR) are vitamin A receptors that are highly expressed in the liver and regulate important physiological processes through regulation of different genes. In this study, we investigated the effect of MTX on RXR-α and RAR-α expression in the liver and the potential protective effects of all-trans retinoic acid (ATRA) in MTX-induced hepatotoxicity. Rats were randomly divided into five groups: The rates were treated with saline, DMSO, MTX (20 mg/kg/IP; single dose), ATRA (7.5 mg/kg/day, I.P), or MTX and ATRA. Rats were killed 24 h after the last ATRA injection. The liver tissues were dissected out, weighed, and subjected to histological, immunohistochemical, and biochemical examinations. Our results demonstrated that treatment with MTX resulted in significant decrease in reduced glutathione (GSH) content and superoxide dismutase (SOD) activity, with concomitant increase in ALT, AST, and MDA levels. In addition, MTX markedly downregulated the expression of both RXR-α and RAR-α, and changed the appearance of RXR-α to be very small speckled droplets. Treatment with ATRA significantly ameliorated MTX-induced effects on GSH, ALT, and MDA. Moreover, ATRA administration increased the expression and nuclear translocation of RXR-α in rat hepatocytes. In conclusion, our study revealed, for the first time, that retinoid receptors may play an important role in the MTX-induced hepatotoxicity.
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9
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Mezaki Y, Morii M, Hebiguchi T, Yoshikawa K, Yamaguchi N, Miura M, Imai K, Yoshino H, Senoo H. Differential increases in the expression of intermediate filament proteins and concomitant morphological changes of transdifferentiating rat hepatic stellate cells observed in vitro. Acta Histochem Cytochem 2013; 46:137-43. [PMID: 24194627 PMCID: PMC3813821 DOI: 10.1267/ahc.13007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 08/30/2013] [Indexed: 01/17/2023] Open
Abstract
The primary function of hepatic stellate cells (HSCs) is the storage of vitamin A. However, they are also responsible for liver fibrosis and are therapeutic targets for treatment of liver cirrhosis. Among the many molecular markers that define quiescent or activated states of HSCs, the characteristics of type III intermediate filaments are of particular interest. Whereas vimentin and desmin are upregulated in activated HSCs, glial fibrillary acidic protein is downregulated in activated HSCs. The functional differences between vimentin and desmin are poorly understood. By time-course quantifications of several molecular markers for HSC activation, we observed that the expression of vimentin preceded that of desmin during the transdifferentiation of HSCs. The immunoreactivity of vimentin in transdifferentiated HSCs was more intense in perinuclear regions compared to that of desmin. We propose that the delayed expression of desmin following the expression of vimentin and the peripheral localization of desmin compared to vimentin are both related to the more extended phenotype of transdifferentiating HSCs observed in vitro.
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Affiliation(s)
- Yoshihiro Mezaki
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
| | - Mayako Morii
- Department of Pediatric Surgery, Akita University Graduate School of Medicine
| | - Taku Hebiguchi
- Department of Pediatric Surgery, Akita University Graduate School of Medicine
| | - Kiwamu Yoshikawa
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
| | - Noriko Yamaguchi
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
| | - Mitsutaka Miura
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
| | - Katsuyuki Imai
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
| | - Hiroaki Yoshino
- Department of Pediatric Surgery, Akita University Graduate School of Medicine
| | - Haruki Senoo
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine
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10
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Senoo H, Mezaki Y, Morii M, Hebiguchi T, Miura M, Imai K. Uptake and storage of vitamin A as lipid droplets in the cytoplasm of cells in the lamina propria mucosae of the rat intestine. Cell Biol Int 2013; 37:1171-80. [PMID: 23765517 DOI: 10.1002/cbin.10140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 06/06/2013] [Indexed: 12/30/2022]
Abstract
Vitamin A (retinyl palmitate) was injected subcutaneously or administered to rats by tube feeding. After subcutaneous injection, vitamin A was taken up and stored in cells of the lamina propria mucosae of the rat intestine. After oral administration, vitamin A was absorbed by the intestinal absorptive epithelial cells and transferred to cells of the lamina propria mucosae, where cells took up and stored the transferred vitamin A. The morphology of these cells was similar to that of hepatic stellate cells (also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells or Ito cells). Thus, these cells in the intestine could take up vitamin A from the systemic circulation and as well as by intestinal absorption, and store the vitamin in the lipid droplets in their cytoplasm. The data suggest that these cells are extrahepatic stellate cells of the digestive tract that may play roles in both the absorption and homeostasis of vitamin A.
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Affiliation(s)
- Haruki Senoo
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita, 010-8543, Japan
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11
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Mezaki Y, Morii M, Hebiguchi T, Yoshikawa K, Yamaguchi N, Yoshino H, Senoo H. The role of retinoic acid receptors in activated hepatic stellate cells. Med Hypotheses 2013; 81:222-4. [PMID: 23688744 DOI: 10.1016/j.mehy.2013.04.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 04/26/2013] [Indexed: 02/02/2023]
Abstract
Hepatic stellate cells (HSCs), also known as Ito cells, fat-storing cells, vitamin A-storing cells or lipocytes, reside in the spaces between hepatocytes and liver sinusoids. Vitamin A storage within the HSCs is achieved through the cooperative action of two proteins, cellular retinol-binding protein (CRBP) I and lecithin:retinol acyltransferase (LRAT). After the discovery that HSCs are responsible not only for the storage of vitamin A, but also for the development of liver fibrosis and subsequent liver cirrhosis, HSCs have been considered a therapeutic target for prevention or reversal of liver fibrogenesis. We have reported that HSCs acquire retinoid responsiveness after in vitro activation by post-transcriptional upregulation of retinoic acid receptor α gene expression. Here we extend this observation in relation to the functions of CRBP I and LRAT, and propose a hypothesis that increased retinoid signaling in activated HSCs forms a feedback loop toward vitamin A restoration in the liver.
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Affiliation(s)
- Yoshihiro Mezaki
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
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12
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Senoo H, Imai K, Mezaki Y, Miura M, Morii M, Fujiwara M, Blomhoff R. Accumulation of Vitamin A in the Hepatic Stellate Cell of Arctic Top Predators. Anat Rec (Hoboken) 2012; 295:1660-8. [DOI: 10.1002/ar.22555] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 04/11/2012] [Accepted: 06/14/2012] [Indexed: 11/12/2022]
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13
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Abstract
Quiescent hepatic stellate cells (HSCs) in healthy liver store 80% of total liver retinols and release them depending on the extracellular retinol status. However, HSCs activated by liver injury lose their retinols and produce a considerable amount of extracellular matrix, subsequently leading to liver fibrosis. Emerging evidence suggests that retinols and their metabolites such as retinoic acids (RAs) contribute to liver regeneration, fibrosis and tumor. However, it is not clear yet why HSCs lose retinol, which enzymes are involved in the retinol metabolism of HSCs and what function of retinol metabolites on HSCs upon liver injury. Recently, our group and collaborators have demonstrated that during activation, HSCs not only lose retinols but also metabolize them into RAs by alcohol dehydrogenases and retinaldehyde dehydrogenases. As transcriptional factors, metabolized RAs induce retinoic acid early inducible-1 and suppressor of cytokine signaling 1 in HSCs, which plays an important role in the interaction between HSCs and natural killer cells. In addition, RAs released from HSCs may induce hepatic cannabinoid receptor 1 expression in alcoholic liver steatosis or regulate immune responses upon liver inflammation. The present review summarizes the role of endogenous metabolized RAs on HSCs themselves and on other liver cells including hepatocytes and immune cells. Moreover, the effects of exogenous retinol and RA treatments on HSCs and liver disease are discussed.
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Affiliation(s)
- Young-Sun Lee
- Laboratory of Liver Research, Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
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Mezaki Y, Morii M, Yoshikawa K, Yamaguchi N, Miura M, Imai K, Yoshino H, Senoo H. Characterization of a cellular retinol-binding protein from lamprey, Lethenteron japonicum. Comp Biochem Physiol B Biochem Mol Biol 2011; 161:233-9. [PMID: 22155549 DOI: 10.1016/j.cbpb.2011.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 11/23/2011] [Accepted: 11/24/2011] [Indexed: 11/18/2022]
Abstract
Lampreys are ancestral representatives of vertebrates known as jawless fish. The Japanese lamprey, Lethenteron japonicum, is a parasitic member of the lampreys known to store large amounts of vitamin A within its body. How this storage is achieved, however, is wholly unknown. Within the body, the absorption, transfer and metabolism of vitamin A are regulated by a family of proteins called retinoid-binding proteins. Here we have cloned a cDNA for cellular retinol-binding protein (CRBP) from the Japanese lamprey, and phylogenetic analysis suggests that lamprey CRBP is an ancestor of both CRBP I and II. The lamprey CRBP protein was expressed in bacteria and purified. Binding of the lamprey CRBP to retinol (Kd of 13.2 nM) was identified by fluorimetric titration. However, results obtained with the protein fluorescence quenching technique indicated that lamprey CRBP does not bind to retinal. Northern blot analysis showed that lamprey CRBP mRNA was ubiquitously expressed, although expression was most abundant in the intestine. Together, these results suggest that lamprey CRBP has an important role in absorbing vitamin A from the blood of host animals.
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Affiliation(s)
- Yoshihiro Mezaki
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
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15
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Huber A, Badylak SF. Phenotypic changes in cultured smooth muscle cells: limitation or opportunity for tissue engineering of hollow organs? J Tissue Eng Regen Med 2011; 6:505-11. [PMID: 21755602 DOI: 10.1002/term.451] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 05/23/2011] [Indexed: 01/27/2023]
Abstract
Smooth muscle cells (SMCs) are typically used as a cell source for the reconstruction of hollow organs by conventional tissue engineering techniques. However, the necessity for and advantage of the use of tissue-specific SMCs are unknown. The present study investigated the phenotypic changes that occur following isolation and in vitro expansion of rat SMC populations isolated from three different tissues: the aorta, oesophagus and urinary bladder. rSMCs were isolated by enzymatic dispersion and expanded by conventional cell culture techniques, yielding microscopically homogeneous populations. SMC phenotypes were monitored according to their expression of marker proteins during the first two passages. Two of the three SMC populations (rSMC-a and rSMC-e) showed a marked change in their marker protein profiles during the first two passages, which resulted in a homogeneous phenotype that was neither fully contractile nor fully synthetic. SMCs from the urinary bladder did not show such a shift. Differences between the three rSMC populations were observed with regard to proliferative activity and gene expression patterns, suggesting the retention of some tissue-specific cell characteristics. In summary, phenotypic changes in SMCs occur as a result of conventional cell isolation and expansion techniques, thus questioning the necessity for a tissue-specific cell source for regenerative medicine applications.
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Affiliation(s)
- Alexander Huber
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
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Hepatic stellate cell (vitamin A-storing cell) and its relative--past, present and future. Cell Biol Int 2011; 34:1247-72. [PMID: 21067523 DOI: 10.1042/cbi20100321] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
HSCs (hepatic stellate cells) (also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells or Ito cells) exist in the space between parenchymal cells and liver sinusoidal endothelial cells of the hepatic lobule and store 50-80% of vitamin A in the whole body as retinyl palmitate in lipid droplets in the cytoplasm. In physiological conditions, these cells play pivotal roles in the regulation of vitamin A homoeostasis. In pathological conditions, such as hepatic fibrosis or liver cirrhosis, HSCs lose vitamin A and synthesize a large amount of extracellular matrix components including collagen, proteoglycan, glycosaminoglycan and adhesive glycoproteins. Morphology of these cells also changes from the star-shaped SCs (stellate cells) to that of fibroblasts or myofibroblasts. The hepatic SCs are now considered to be targets of therapy of hepatic fibrosis or liver cirrhosis. HSCs are activated by adhering to the parenchymal cells and lose stored vitamin A during hepatic regeneration. Vitamin A-storing cells exist in extrahepatic organs such as the pancreas, lungs, kidneys and intestines. Vitamin A-storing cells in the liver and extrahepatic organs form a cellular system. The research of the vitamin A-storing cells has developed and expanded vigorously. The past, present and future of the research of the vitamin A-storing cells (SCs) will be summarized and discussed in this review.
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Mann J, Mann DA. Transcriptional regulation of hepatic stellate cells. Adv Drug Deliv Rev 2009; 61:497-512. [PMID: 19393271 DOI: 10.1016/j.addr.2009.03.011] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 03/10/2009] [Indexed: 02/08/2023]
Abstract
Hepatic stellate cell (HSC) activation is a process of cellular transdifferentiation in which, upon liver injury, the quiescent vitamin A storing perisinusoidal HSC is converted into a wound-healing myofibroblast and acquires potent pro-inflammatory and pro-fibrogenic activities. This remarkable phenotypic transformation is underpinned by changes in the expression of a vast number of genes. In this review we survey current knowledge of the transcription factors that either control HSC activation or which regulate specific fibrogenic functions of the activated HSC such as collagen expression, proliferation and resistance to apoptosis.
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Smedsrød B, Le Couteur D, Ikejima K, Jaeschke H, Kawada N, Naito M, Knolle P, Nagy L, Senoo H, Vidal-Vanaclocha F, Yamaguchi N. Hepatic sinusoidal cells in health and disease: update from the 14th International Symposium. Liver Int 2009; 29:490-501. [PMID: 19210626 DOI: 10.1111/j.1478-3231.2009.01979.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review aims to give an update of the field of the hepatic sinusoid, supported by references to presentations given at the 14th International Symposium on Cells of the Hepatic Sinusoid (ISCHS2008), which was held in Tromsø, Norway, August 31-September 4, 2008. The subtitle of the symposium, 'Integrating basic and clinical hepatology', signified the inclusion of both basal and applied clinical results of importance in the field of liver sinusoidal physiology and pathophysiology. Of nearly 50 oral presentations, nine were invited tutorial lectures. The authors of the review have avoided writing a 'flat summary' of the presentations given at ISCHS2008, and instead focused on important novel information. The tutorial presentations have served as a particularly important basis in the preparation of this update. In this review, we have also included references to recent literature that may not have been covered by the ISCHS2008 programme. The sections of this review reflect the scientific programme of the symposium (http://www.ub.uit.no/munin/bitstream/10037/1654/1/book.pdf): 1. Liver sinusoidal endothelial cells. 2. Kupffer cells. 3. Hepatic stellate cells. 4. Immunology. 5. Tumor/metastasis. Symposium abstracts are referred to by a number preceded by the letter A.
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Affiliation(s)
- Bård Smedsrød
- Department of Cell Biology and Histology, Institute of Medical Biology, University of Tromsø, Tromsø, Norway.
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Mezaki Y, Yamaguchi N, Yoshikawa K, Miura M, Imai K, Itoh H, Senoo H. Insoluble, speckled cytosolic distribution of retinoic acid receptor alpha protein as a marker of hepatic stellate cell activation in vitro. J Histochem Cytochem 2009; 57:687-99. [PMID: 19332432 DOI: 10.1369/jhc.2009.953208] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Hepatic stellate cells (HSCs) are the major site of retinoid storage, and their activation is a key process in liver fibrogenesis. We have previously shown that expression of the retinoic acid receptor alpha (RARalpha) is upregulated in activated rat HSCs at a posttranscriptional level and that these RARalpha proteins showed a speckled distribution in the cytosol, despite their possession of a nuclear localization signal (NLS). In this report, we further characterize these cytosolic RARalpha proteins by using exogenously expressed RARalpha protein fragments or mutants tagged with a green fluorescent protein. Substitution of four amino acids, 161-164 from lysine to alanine, abolished the NLS. Exogenously expressed RARalpha protein fragments containing an NLS were localized exclusively in the nuclei of activated rat HSCs and never colocalized with the endogenous RARalpha proteins in the cytosol, suggesting that the NLS of endogenous RARalpha proteins is masked. Biochemical analysis showed that 65% of RARalpha proteins in activated HSCs were insoluble in a mixture of detergents. The insolubility of RARalpha proteins makes it difficult to identify RARalpha proteins in activated HSCs. Therefore, we propose that insoluble, speckled cytosolic distribution of RARalpha proteins represents a new marker of HSC activation.
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Affiliation(s)
- Yoshihiro Mezaki
- Department of Cell Biology and Histology, School of Medicine, Akita University, Akita 010-8543, Japan
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Nagatsuma K, Hayashi Y, Hano H, Sagara H, Murakami K, Saito M, Masaki T, Lu T, Tanaka M, Enzan H, Aizawa Y, Tajiri H, Matsuura T. Lecithin: retinol acyltransferase protein is distributed in both hepatic stellate cells and endothelial cells of normal rodent and human liver. Liver Int 2009; 29:47-54. [PMID: 18544127 DOI: 10.1111/j.1478-3231.2008.01773.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND To determine the extent to which hepatic stellate cell (HSC) activation contributes to liver fibrosis, it was found necessary to develop an alternative structural and functional stellate cell marker for in situ studies. Although several HSC markers have been reported, none of those are associated with particular HSC functions. AIM The present study was undertaken to examine whether lecithin:retinol acyltransferase (LRAT), the physiological retinol esterification enzyme of the liver, is a potential and relevant tissue marker for HSC. METHODS An antibody specific to mouse and human LRAT was prepared based on the amino acid sequences. Antibodies to LRAT were used for immunohistochemical studies to assess the distribution of LRAT-positive cells in the liver with the aid of fluorescence and immunogold electron microscopy. RESULTS LRAT-positive cells were found to be confined in the space of Disse, corresponding with the location of desmin-positive HSC in rodent liver, also in human liver. Interestingly, LRAT-positive staining was also observed along the liver sinusoidal endothelial lining. Furthermore, immune electron microscopic studies revealed that LRAT was mainly distributed in HSC within the rough-endoplasmic reticulum (RER) and multivesicular bodies, whereas LRAT staining within the endothelial cells was largely confined to the perinuclear area and to some extent to the RER. CONCLUSION Evidence has been accumulated that LRAT might serve as an excellent alternative HSC marker for future structural and functional studies. Furthermore, the presence of LRAT in endothelial cells might suggest a currently unknown function of this enzyme in liver endothelial biology.
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Affiliation(s)
- Keisuke Nagatsuma
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, The Jikei University School of Medicine, Tokyo, Japan
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Luo XH, Yang Q, Zhang Q, Cheng ML. Screening of genes associated with human hepatic fibrosis using cDNA microarray. Shijie Huaren Xiaohua Zazhi 2008; 16:1525-1529. [DOI: 10.11569/wcjd.v16.i14.1525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To screen the genes associated with human hepatic fibrosis and explore the mechanism of hepatic fibrosis.
METHODS: Total mRNA was obtained from human hepatic fibrosis tissues and normal liver tissues respectively to prepare probe. After hybridization and cleaning, computer scan technique was used to analyze the gene expression maps of liver fibrosis tissues and normal liver tissue. Real-time fluorescence quantitative polymerase chain reaction (FQ-PCR) was adopted to verify the expression changes of some differential genes.
RESULTS: Sixty-eight differential genes were screened out, of which 35 were up-regulated and 33 were down-regulated. These genes were categorized according to their functions as cell signal transmission-regulating genes, DNA impairment and repair genes, translation-regulating factors, metabolism-related genes and function-unknown genes. As compared with that in normal liver tissues, C/EBPβ mRNA expression was down-regulated (22.02 ± 4.82 vs 59.13 ± 8.21, P < 0.01), while MMP-14 mRNA expression was up-regulated (257.33 ± 26.58 vs 21.65 ± 4.37, P < 0.01). This conformed to the results of cDNA microarray.
CONCLUSION: Multiple genes are involved in the formation of hepatic fibrosis and there is a significant difference in gene expression between normal and fibrotic liver tissues.
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