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He Q, He W, Dong H, Guo Y, Yuan G, Shi X, Wang D, Lu F. Role of liver sinusoidal endothelial cell in metabolic dysfunction-associated fatty liver disease. Cell Commun Signal 2024; 22:346. [PMID: 38943171 PMCID: PMC11214243 DOI: 10.1186/s12964-024-01720-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Accepted: 06/20/2024] [Indexed: 07/01/2024] Open
Abstract
Liver sinusoidal endothelial cells (LSECs) are highly specialized endothelial cells that represent the interface between blood cells on one side and hepatocytes on the other side. LSECs not only form a barrier within the hepatic sinus, but also play important physiological functions such as regulating hepatic vascular pressure, anti-inflammatory and anti-fibrotic. Pathologically, pathogenic factors can induce LSECs capillarization, that is, loss of fenestra and dysfunction, which are conducive to early steatosis, lay the foundation for the progression of metabolic dysfunction-associated fatty liver disease (MAFLD), and accelerate metabolic dysfunction-associated steatohepatitis (MASH) and liver fibrosis. The unique localization, phenotype, and function of LSECs make them potential candidates for reducing liver injury, inflammation, and preventing or reversing fibrosis in the future.
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Affiliation(s)
- Qiongyao He
- Institute of Integrated Traditional Chinese and Western Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wu He
- Division of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, 430030, China
| | - Hui Dong
- Department of Integrated Traditional Chinese and Western Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yujin Guo
- Institute of Integrated Traditional Chinese and Western Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Gang Yuan
- Department of Endocrinology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiaoli Shi
- Department of Endocrinology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Dingkun Wang
- Department of Integrated Traditional Chinese and Western Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Fuer Lu
- Department of Integrated Traditional Chinese and Western Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, 430030, China.
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2
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Baffy G, Portincasa P. Gut Microbiota and Sinusoidal Vasoregulation in MASLD: A Portal Perspective. Metabolites 2024; 14:324. [PMID: 38921459 PMCID: PMC11205793 DOI: 10.3390/metabo14060324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 05/30/2024] [Accepted: 06/06/2024] [Indexed: 06/27/2024] Open
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a common condition with heterogeneous outcomes difficult to predict at the individual level. Feared complications of advanced MASLD are linked to clinically significant portal hypertension and are initiated by functional and mechanical changes in the unique sinusoidal capillary network of the liver. Early sinusoidal vasoregulatory changes in MASLD lead to increased intrahepatic vascular resistance and represent the beginning of portal hypertension. In addition, the composition and function of gut microbiota in MASLD are distinctly different from the healthy state, and multiple lines of evidence demonstrate the association of dysbiosis with these vasoregulatory changes. The gut microbiota is involved in the biotransformation of nutrients, production of de novo metabolites, release of microbial structural components, and impairment of the intestinal barrier with impact on innate immune responses, metabolism, inflammation, fibrosis, and vasoregulation in the liver and beyond. The gut-liver axis is a conceptual framework in which portal circulation is the primary connection between gut microbiota and the liver. Accordingly, biochemical and hemodynamic attributes of portal circulation may hold the key to better understanding and predicting disease progression in MASLD. However, many specific details remain hidden due to limited access to the portal circulation, indicating a major unmet need for the development of innovative diagnostic tools to analyze portal metabolites and explore their effect on health and disease. We also need to safely and reliably monitor portal hemodynamics with the goal of providing preventive and curative interventions in all stages of MASLD. Here, we review recent advances that link portal metabolomics to altered sinusoidal vasoregulation and may allow for new insights into the development of portal hypertension in MASLD.
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Affiliation(s)
- Gyorgy Baffy
- Section of Gastroenterology, Department of Medicine, VA Boston Healthcare System, Boston, MA 02130, USA
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Piero Portincasa
- Division of Internal Medicine, Department of Precision and Regenerative Medicine, University ‘Aldo Moro’ Medical School, 70121 Bari, Italy;
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3
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Van Eyck A, Kwanten WJ, Peleman C, Makhout S, Van Laere S, Van De Maele K, Van Hoorenbeeck K, De Man J, De Winter BY, Francque S, Verhulst SL. The role of adipose tissue and subsequent liver tissue hypoxia in obesity and early stage metabolic dysfunction associated steatotic liver disease. Int J Obes (Lond) 2024; 48:512-522. [PMID: 38142264 DOI: 10.1038/s41366-023-01443-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/21/2023] [Accepted: 12/05/2023] [Indexed: 12/25/2023]
Abstract
BACKGROUND Obesity is linked to several health complication, including Metabolic Dysfunction Associated Steatotic Liver Disease (MASLD). Adipose tissue hypoxia has been suggested as an important player in the pathophysiological mechanism leading to chronic inflammation in obesity, and in the progression of MASLD. The study aims to investigate the effect of progressive obesity on adipose and liver tissue hypoxia. METHODS Male 8-week-old C57BL/6J mice were fed a high-fat high-fructose diet (HFHFD) or control diet (CD) for 4, 8, 12, 16 and 20 weeks. Serum ALT, AST and lipid levels were determined, and glucose and insulin tolerance testing was performed. Liver, gonadal and subcutaneous adipose tissue was assessed histologically. In vivo tissue pO2 measurements were performed in gonadal adipose tissue and liver under anesthesia. A PCR array for hypoxia responsive genes was performed in liver and adipose tissue. The main findings in the liver were validated in another diet-induced MASLD mice model, the choline-deficient L-amino acid defined high-fat diet (CDAHFD). RESULTS HFHFD feeding induced a progressive obesity, dyslipidaemia, insulin resistance and MASLD. In vivo pO2 was decreased in gonadal adipose tissue after 8 weeks of HFHFD compared to CD, and decreased further until 20 weeks. Liver pO2 was only significantly decreased after 16 and 20 weeks of HFHFD. Gene expression and histology confirmed the presence of hypoxia in liver and adipose tissue. Hypoxia could not be confirmed in mice fed a CDAHFD. CONCLUSION Diet-induced obesity in mice is associated with hypoxia in liver and adipose tissue. Adipose tissue hypoxia develops early in obesity, while liver hypoxia occurs later in the obesity development but still within the early stages of MASLD. Liver hypoxia could not be directly confirmed in a non-obese liver-only MASLD mice model, indicating that obesity-related processes such as adipose tissue hypoxia are important in the pathophysiology of obesity and MASLD.
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Affiliation(s)
- Annelies Van Eyck
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium.
- Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium.
| | - Wilhelmus J Kwanten
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Edegem, Belgium
| | - Cédric Peleman
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Edegem, Belgium
| | - Sanae Makhout
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Steven Van Laere
- Center of Oncological Research (CORE), MIPRO, IPPON, University of Antwerp, Antwerp, Belgium
| | - Karolien Van De Maele
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium
| | - Kim Van Hoorenbeeck
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium
| | - Joris De Man
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Benedicte Y De Winter
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Edegem, Belgium
| | - Sven Francque
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Edegem, Belgium
| | - Stijn L Verhulst
- Laboratory of Experimental Medicine and Pediatrics and member of the Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium
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4
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Driessen S, Francque SM, Anker SD, Castro Cabezas M, Grobbee DE, Tushuizen ME, Holleboom AG. Metabolic dysfunction-associated steatotic liver disease and the heart. Hepatology 2023:01515467-990000000-00699. [PMID: 38147315 DOI: 10.1097/hep.0000000000000735] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 11/13/2023] [Indexed: 12/27/2023]
Abstract
The prevalence and severity of metabolic dysfunction-associated steatotic liver disease (MASLD) are increasing. Physicians who treat patients with MASLD may acknowledge the strong coincidence with cardiometabolic disease, including atherosclerotic cardiovascular disease (asCVD). This raises questions on co-occurrence, causality, and the need for screening and multidisciplinary care for MASLD in patients with asCVD, and vice versa. Here, we review the interrelations of MASLD and heart disease and formulate answers to these matters. Epidemiological studies scoring proxies for atherosclerosis and actual cardiovascular events indicate increased atherosclerosis in patients with MASLD, yet no increased risk of asCVD mortality. MASLD and asCVD share common drivers: obesity, insulin resistance and type 2 diabetes mellitus (T2DM), smoking, hypertension, and sleep apnea syndrome. In addition, Mendelian randomization studies support that MASLD may cause atherosclerosis through mixed hyperlipidemia, while such evidence is lacking for liver-derived procoagulant factors. In the more advanced fibrotic stages, MASLD may contribute to heart failure with preserved ejection fraction by reduced filling of the right ventricle, which may induce fatigue upon exertion, often mentioned by patients with MASLD. Some evidence points to an association between MASLD and cardiac arrhythmias. Regarding treatment and given the strong co-occurrence of MASLD and asCVD, pharmacotherapy in development for advanced stages of MASLD would ideally also reduce cardiovascular events, as has been demonstrated for T2DM treatments. Given the common drivers, potential causal factors and especially given the increased rate of cardiovascular events, comprehensive cardiometabolic risk management is warranted in patients with MASLD, preferably in a multidisciplinary approach.
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Affiliation(s)
- Stan Driessen
- Department of Vascular Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Sven M Francque
- Department of Gastroenterology and Hepatology, University Hospital Antwerp, Antwerp, Belgium
| | - Stefan D Anker
- Department of Cardiology (CVK) of German Heart Center Charité, Institute of Health Center for Regenerative Therapies (BCRT), German Centre for Cardiovascular Research (DZHK) partner site Berlin, Charité Universitätsmedizin, Berlin, Germany
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Manuel Castro Cabezas
- Julius Clinical, Zeist, The Netherlands
- Department of Internal Medicine, Franciscus Gasthuis and Vlietland, Rotterdam, The Netherlands
- Department of Internal Medicine and Endocrinology, Erasmus MC, Rotterdam, The Netherlands
| | - Diederick E Grobbee
- Julius Clinical, Zeist, The Netherlands
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Maarten E Tushuizen
- Department of Gastroenterology and Hepatology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Adriaan G Holleboom
- Department of Vascular Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
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Mitten EK, Portincasa P, Baffy G. Portal Hypertension in Nonalcoholic Fatty Liver Disease: Challenges and Paradigms. J Clin Transl Hepatol 2023; 11:1201-1211. [PMID: 37577237 PMCID: PMC10412712 DOI: 10.14218/jcth.2023.00029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 05/04/2023] [Accepted: 05/17/2023] [Indexed: 07/03/2023] Open
Abstract
Portal hypertension in cirrhosis is defined as an increase in the portal pressure gradient (PPG) between the portal and hepatic veins and is traditionally estimated by the hepatic venous pressure gradient (HVPG), which is the difference in pressure between the free-floating and wedged positions of a balloon catheter in the hepatic vein. By convention, HVPG≥10 mmHg indicates clinically significant portal hypertension, which is associated with adverse clinical outcomes. Nonalcoholic fatty liver disease (NAFLD) is a common disorder with a heterogeneous clinical course, which includes the development of portal hypertension. There is increasing evidence that portal hypertension in NAFLD deserves special considerations. First, elevated PPG often precedes fibrosis in NAFLD, suggesting a bidirectional relationship between these pathological processes. Second, HVPG underestimates PPG in NAFLD, suggesting that portal hypertension is more prevalent in this condition than currently believed. Third, cellular mechanoresponses generated early in the pathogenesis of NAFLD provide a mechanistic explanation for the pressure-fibrosis paradigm. Finally, a better understanding of liver mechanobiology in NAFLD may aid in the development of novel pharmaceutical targets for prevention and management of this disease.
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Affiliation(s)
- Emilie K. Mitten
- Division of Gastroenterology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Piero Portincasa
- Division of Internal Medicine and Department of Precision and Regenerative Medicine and Ionian Area, University ‘Aldo Moro’ Medical School, Bari, Italy
| | - György Baffy
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Section of Gastroenterology, Department of Medicine, VA Boston Healthcare System, Boston, MA, USA
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6
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Bukofzer S, Harris G, Song S, Cable EE. OCE-205, a Selective V1a Partial Agonist, Reduces Portal Pressure in Rat Models of Portal Hypertension. J Exp Pharmacol 2023; 15:279-290. [PMID: 37469992 PMCID: PMC10352125 DOI: 10.2147/jep.s416673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
Purpose Management of decompensated cirrhosis may include the use of vasoconstrictors that can lead to serious adverse events. OCE-205 was designed as a highly selective V1a receptor partial agonist, intended to have a wider therapeutic window than full vasopressin agonists. Methods We aimed to characterize the activity of OCE-205 treatment in two rat models of portal hypertension (PHT). For both models, OCE-205 was administered as a subcutaneous bolus injection. Thirty male Wistar rats were fed a methionine/choline-deficient (MCD) diet to model PHT. Animals received OCE-205 (10, 25, 100, or 500 µg/kg) or intra-arterial terlipressin (100 µg/kg). In a more severe model of PHT, 11 male Sprague Dawley rats had the common bile duct surgically ligated (BDL) and received OCE-205. Portal pressure (PP) and mean arterial pressure (MAP) were measured. Results For PP in the MCD model, MAP increased while PP decreased in rats treated with OCE-205 or terlipressin; the peak changes to MAP were 14.7 and 33.5 mmHg, respectively. Changes in MAP began to plateau after 10 min in the OCE-205 groups, whereas in the terlipressin group, MAP rapidly increased and peaked after 20 min. Across all treatment groups in the BDL model, a dose-related decrease from baseline in PP was observed following OCE-205, plateauing as the dose increased. In all treatment groups, PP change remained negative throughout the 30-min testing period. In both PHT rat models, a reduction in PP was coupled to an increase in MAP, with both plateauing in dose-response curves. Conclusion Data support OCE-205 as a promising candidate for further development. Institutional Protocol Number Procedures were approved by the Ferring Research Institute (FRI) Institutional Animal Care and Use Committee on July 13, 2011, under protocol FRI-07-0002.
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Affiliation(s)
| | | | - Susan Song
- Ferring Research Institute Inc., San Diego, CA, USA
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7
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Li D, Janmey PA, Wells RG. Local fat content determines global and local stiffness in livers with simple steatosis. FASEB Bioadv 2023; 5:251-261. [PMID: 37287868 PMCID: PMC10242205 DOI: 10.1096/fba.2022-00134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/09/2023] [Accepted: 04/04/2023] [Indexed: 06/09/2023] Open
Abstract
Fat accumulation during liver steatosis precedes inflammation and fibrosis in fatty liver diseases, and is associated with disease progression. Despite a large body of evidence that liver mechanics play a major role in liver disease progression, the effect of fat accumulation by itself on liver mechanics remains unclear. Thus, we conducted ex vivo studies of liver mechanics in rodent models of simple steatosis to isolate and examine the mechanical effects of intrahepatic fat accumulation, and found that fat accumulation softens the liver. Using a novel adaptation of microindentation to permit association of local mechanics with microarchitectural features, we found evidence that the softening of fatty liver results from local softening of fatty regions rather than uniform softening of the liver. These results suggest that fat accumulation itself exerts a softening effect on liver tissue. This, along with the localized heterogeneity of softening within the liver, has implications in what mechanical mechanisms are involved in the progression of liver steatosis to more severe pathologies and disease. Finally, the ability to examine and associate local mechanics with microarchitectural features is potentially applicable to the study of the role of heterogeneous mechanical microenvironments in both other liver pathologies and other organ systems.
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Affiliation(s)
- David Li
- Division of Gastroenterology and HepatologyDepartment of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- NSF Science and Technology Center for Engineering MechanoBiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Paul A. Janmey
- NSF Science and Technology Center for Engineering MechanoBiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Institute for Medicine and EngineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of PhysiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Rebecca G. Wells
- Division of Gastroenterology and HepatologyDepartment of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- NSF Science and Technology Center for Engineering MechanoBiologyUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
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8
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Adori M, Bhat S, Gramignoli R, Valladolid-Acebes I, Bengtsson T, Uhlèn M, Adori C. Hepatic Innervations and Nonalcoholic Fatty Liver Disease. Semin Liver Dis 2023; 43:149-162. [PMID: 37156523 PMCID: PMC10348844 DOI: 10.1055/s-0043-57237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder. Increased sympathetic (noradrenergic) nerve tone has a complex role in the etiopathomechanism of NAFLD, affecting the development/progression of steatosis, inflammation, fibrosis, and liver hemodynamical alterations. Also, lipid sensing by vagal afferent fibers is an important player in the development of hepatic steatosis. Moreover, disorganization and progressive degeneration of liver sympathetic nerves were recently described in human and experimental NAFLD. These structural alterations likely come along with impaired liver sympathetic nerve functionality and lack of adequate hepatic noradrenergic signaling. Here, we first overview the anatomy and physiology of liver nerves. Then, we discuss the nerve impairments in NAFLD and their pathophysiological consequences in hepatic metabolism, inflammation, fibrosis, and hemodynamics. We conclude that further studies considering the spatial-temporal dynamics of structural and functional changes in the hepatic nervous system may lead to more targeted pharmacotherapeutic advances in NAFLD.
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Affiliation(s)
- Monika Adori
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Sadam Bhat
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Roberto Gramignoli
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Ismael Valladolid-Acebes
- Department of Molecular Medicine and Surgery, The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Tore Bengtsson
- Department of Molecular Biosciences, The Wenner-Gren Institute (MBW), Stockholm University, Stockholm, Sweden
| | - Mathias Uhlèn
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Science for Life Laboratory, Royal Institute of Technology, Stockholm, Sweden
| | - Csaba Adori
- Department of Molecular Biosciences, The Wenner-Gren Institute (MBW), Stockholm University, Stockholm, Sweden
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Interventional Management of Portal Hypertension in Cancer Patients. Curr Oncol Rep 2022; 24:1461-1475. [PMID: 35953600 DOI: 10.1007/s11912-022-01319-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/09/2022] [Indexed: 01/27/2023]
Abstract
PURPOSE OF REVIEW To provide an overview of the classifications and clinical hallmarks of common cancer-related conditions that contribute to the high incidence of portal hypertension in this population and provide an update on currently available interventional radiology therapeutic approaches. RECENT FINDINGS In the last few decades, there have been significant advancements in understanding the pathophysiology of portal hypertension. This knowledge has led to the development of safer and more effective minimally invasive approaches. The main objective is to provide alternatives to prevent life-threatening complications from clinically significant portal hypertension and to allow the continuation of cancer treatment interventions that would otherwise be stopped. Clinicians involved in cancer care should be aware of risk factors, associated complications, and management of portal hypertension in cancer patients. Interventional radiology offers minimally invasive alternatives that play a central role in improving clinical outcomes and survival of these patients, allowing the continuation of cancer treatments.
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10
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Dalbeni A, Castelli M, Zoncapè M, Minuz P, Sacerdoti D. Platelets in Non-alcoholic Fatty Liver Disease. Front Pharmacol 2022; 13:842636. [PMID: 35250588 PMCID: PMC8895200 DOI: 10.3389/fphar.2022.842636] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/03/2022] [Indexed: 12/17/2022] Open
Abstract
Non alcoholic steatohepatitis (NASH) is the inflammatory reaction of the liver to excessive accumulation of lipids in the hepatocytes. NASH can progress to cirrhosis and hepatocellular carcinoma (HCC). Fatty liver is the hepatic manifestation of metabolic syndrome. A subclinical inflammatory state is present in patients with metabolic alterations like insulin resistance, type-2 diabetes, obesity, hyperlipidemia, and hypertension. Platelets participate in immune cells recruitment and cytokines-induced liver damage. It is hypothesized that lipid toxicity cause accumulation of platelets in the liver, platelet adhesion and activation, which primes the immunoinflammatory reaction and activation of stellate cells. Recent data suggest that antiplatelet drugs may interrupt this cascade and prevent/improve NASH. They may also improve some metabolic alterations. The pathophysiology of inflammatory liver disease and the implication of platelets are discussed in details.
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Affiliation(s)
- Andrea Dalbeni
- Division of General Medicine C, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
- Liver Unit, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
| | - Marco Castelli
- Division of General Medicine C, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
| | - Mirko Zoncapè
- Division of General Medicine C, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
- Liver Unit, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
| | - Pietro Minuz
- Division of General Medicine C, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
- *Correspondence: Pietro Minuz,
| | - David Sacerdoti
- Liver Unit, Department of Medicine, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
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van der Graaff D, Chotkoe S, De Winter B, De Man J, Casteleyn C, Timmermans JP, Pintelon I, Vonghia L, Kwanten WJ, Francque S. Vasoconstrictor antagonism improves functional and structural vascular alterations and liver damage in rats with early NAFLD. JHEP Rep 2022; 4:100412. [PMID: 35036886 PMCID: PMC8749167 DOI: 10.1016/j.jhepr.2021.100412] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND & AIMS Intrahepatic vascular resistance is increased in early non-alcoholic fatty liver disease (NAFLD), potentially leading to tissue hypoxia and triggering disease progression. Hepatic vascular hyperreactivity to vasoconstrictors has been identified as an underlying mechanism. This study investigates vasoconstrictive agonism and antagonism in 2 models of early NAFLD and in non-alcoholic steatohepatitis (NASH). METHODS The effects of endothelin-1 (ET-1), angiotensin II (ATII) and thromboxane A2 (TxA2) agonism and antagonism were studied by in situ ex vivo liver perfusion and preventive/therapeutic treatment experiments in a methionine-choline-deficient diet model of steatosis. Furthermore, important results were validated in Zucker fatty rats after 4 or 8 weeks of high-fat high-fructose diet feeding. In vivo systemic and portal pressures, ex vivo transhepatic pressure gradients (THPG) and transaminase levels were measured. Liver tissue was harvested for structural and mRNA analysis. RESULTS The THPG and consequent portal pressure were significantly increased in both models of steatosis and in NASH. ET-1, ATII and TxA2 increased the THPG even further. Bosentan (ET-1 receptor antagonist), valsartan (ATII receptor blocker) and celecoxib (COX-2 inhibitor) attenuated or even normalised the increased THPG in steatosis. Simultaneously, bosentan and valsartan treatment improved transaminase levels. Moreover, bosentan was able to mitigate the degree of steatosis and restored the disrupted microvascular structure. Finally, beneficial vascular effects of bosentan endured in NASH. CONCLUSIONS Antagonism of vasoconstrictive mediators improves intrahepatic vascular function. Both ET-1 and ATII antagonists showed additional benefit and bosentan even mitigated steatosis and structural liver damage. In conclusion, vasoconstrictive antagonism is a potentially promising therapeutic option for the treatment of early NAFLD. LAY SUMMARY In non-alcoholic fatty liver disease (NAFLD), hepatic blood flow is impaired and the blood pressure in the liver blood vessels is increased as a result of an increased response of the liver vasculature to vasoconstrictors. Using drugs to block the constriction of the intrahepatic vasculature, the resistance of the liver blood vessels decreases and the increased portal pressure is reduced. Moreover, blocking the vasoconstrictive endothelin-1 pathway restored parenchymal architecture and reduced disease severity.
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Key Words
- ALT, alanine aminotransferase
- ARB, angiotensin receptor blocker
- AST, aspartate aminotransferase
- ATII, angiotensin II
- COX, cyclooxygenase
- ET, endothelin
- HFHFD, high-fat high-fructose diet
- IHVR, intrahepatic vascular resistance
- Jak2, Janus-kinase-2
- MCD, methionine-choline deficient diet
- Mx, methoxamine
- NAFLD, non-alcoholic fatty liver disease
- NASH, non-alcoholic steatohepatitis
- NO, nitric oxide
- PP, portal pressure
- PR, pulse rate
- SEM, scanning electron microscopy
- TBW, total body weight
- TEM, transmission electron microscopy
- TXAS, thromboxane synthase
- TxA2, thromboxane A2
- ZFR, Zucker fatty rats
- angiotensin II
- endothelin-1
- non-alcoholic fatty liver disease
- portal hypertension
- thromboxane A2
- transhepatic pressure gradient
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Affiliation(s)
- Denise van der Graaff
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Shivani Chotkoe
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Benedicte De Winter
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Joris De Man
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Christophe Casteleyn
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
- Department of Applied Veterinary Morphology, Faculty of Veterinary Medicine, University of Antwerp, Antwerp, Belgium
| | - Jean-Pierre Timmermans
- Laboratory of Cell Biology and Histology, Antwerp Centre for Advanced Microscopy (ACAM), University of Antwerp, Antwerp, Belgium
| | - Isabel Pintelon
- Laboratory of Cell Biology and Histology, Antwerp Centre for Advanced Microscopy (ACAM), University of Antwerp, Antwerp, Belgium
| | - Luisa Vonghia
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Wilhelmus J. Kwanten
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Sven Francque
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, Antwerp, Belgium
- European Reference Network Rare Hepatic Diseases (ERN RARE-LIVER)
- Laboratory of Experimental Medicine and Pediatrics (LEMP), Division of Gastroenterology-Hepatology, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
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12
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Rong L, Zou J, Ran W, Qi X, Chen Y, Cui H, Guo J. Advancements in the treatment of non-alcoholic fatty liver disease (NAFLD). Front Endocrinol (Lausanne) 2022; 13:1087260. [PMID: 36726464 PMCID: PMC9884828 DOI: 10.3389/fendo.2022.1087260] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/28/2022] [Indexed: 01/17/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a series of diseases, involving excessive lipid deposition in the liver and is often accompanied by obesity, diabetes, dyslipidemia, abnormal blood pressure, and other metabolic disorders. In order to more accurately reflect its pathogenesis, an international consensus renamed NAFLD in 2020 as metabolic (dysfunction) associated with fatty liver disease (MAFLD). The changes in diet and lifestyle are recognized the non-drug treatment strategies; however, due to the complex pathogenesis of NAFLD, the current drug therapies are mainly focused on its pathogenic factors, key links of pathogenesis, and related metabolic disorders as targets. There is still a lack of specific drugs. In clinical studies, the common NAFLD treatments include the regulation of glucose and lipid metabolism to protect the liver and anti-inflammation. The NAFLD treatments based on the enterohepatic axis, targeting gut microbiota, are gradually emerging, and various new metabolism-regulating drugs are also under clinical development. Therefore, this review article has comprehensively discussed the research advancements in NAFLD treatment in recent years.
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Affiliation(s)
- Li Rong
- Department of Gastroenterology, Bishan Hospital of Chongqing Medical University, Bishan Hospital of Chongqing, Chongqing, China
| | - Junyan Zou
- Medical Research Institute, Southwest University, Chongqing, China
- Medical Research Institute, Southwest University, Public Health Hospital Affiliated to Southwest University, Chongqing, China
| | - Wei Ran
- Medical Research Institute, Southwest University, Public Health Hospital Affiliated to Southwest University, Chongqing, China
| | - Xiaohong Qi
- Department of General surgery, Baoshan People’s Hospital of Yunnan Province, Baoshan, Yunnan, China
| | - Yaokai Chen
- Medical Research Institute, Southwest University, Public Health Hospital Affiliated to Southwest University, Chongqing, China
| | - Hongjuan Cui
- Medical Research Institute, Southwest University, Chongqing, China
| | - Jinjun Guo
- Department of Gastroenterology, Bishan Hospital of Chongqing Medical University, Bishan Hospital of Chongqing, Chongqing, China
- *Correspondence: Jinjun Guo,
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13
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Adori C, Daraio T, Kuiper R, Barde S, Horvathova L, Yoshitake T, Ihnatko R, Valladolid-Acebes I, Vercruysse P, Wellendorf AM, Gramignoli R, Bozoky B, Kehr J, Theodorsson E, Cancelas JA, Mravec B, Jorns C, Ellis E, Mulder J, Uhlén M, Bark C, Hökfelt T. Disorganization and degeneration of liver sympathetic innervations in nonalcoholic fatty liver disease revealed by 3D imaging. SCIENCE ADVANCES 2021; 7:7/30/eabg5733. [PMID: 34290096 PMCID: PMC8294768 DOI: 10.1126/sciadv.abg5733] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 06/04/2021] [Indexed: 05/08/2023]
Abstract
Hepatic nerves have a complex role in synchronizing liver metabolism. Here, we used three-dimensional (3D) immunoimaging to explore the integrity of the hepatic nervous system in experimental and human nonalcoholic fatty liver disease (NAFLD). We demonstrate parallel signs of mild degeneration and axonal sprouting of sympathetic innervations in early stages of experimental NAFLD and a collapse of sympathetic arborization in steatohepatitis. Human fatty livers display a similar pattern of sympathetic nerve degeneration, correlating with the severity of NAFLD pathology. We show that chronic sympathetic hyperexcitation is a key factor in the axonal degeneration, here genetically phenocopied in mice deficient of the Rac-1 activator Vav3. In experimental steatohepatitis, 3D imaging reveals a severe portal vein contraction, spatially correlated with the extension of the remaining nerves around the portal vein, enlightening a potential intrahepatic neuronal mechanism of portal hypertension. These fundamental alterations in liver innervation and vasculature uncover previously unidentified neuronal components in NAFLD pathomechanisms.
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Affiliation(s)
- Csaba Adori
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden.
| | - Teresa Daraio
- The Rolf Luft Research Center for Diabetes and Endocrinology, Department of Molecular Medicine and Surgery, Karolinska Institutet, 17176 Stockholm, Sweden
| | - Raoul Kuiper
- Department of Laboratory Medicine, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Swapnali Barde
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Lubica Horvathova
- Biomedical Research Center, Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Takashi Yoshitake
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Robert Ihnatko
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, 58285 Linköping, Sweden
| | - Ismael Valladolid-Acebes
- The Rolf Luft Research Center for Diabetes and Endocrinology, Department of Molecular Medicine and Surgery, Karolinska Institutet, 17176 Stockholm, Sweden
| | - Pauline Vercruysse
- The Rolf Luft Research Center for Diabetes and Endocrinology, Department of Molecular Medicine and Surgery, Karolinska Institutet, 17176 Stockholm, Sweden
| | - Ashley M Wellendorf
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
| | - Roberto Gramignoli
- Department of Laboratory Medicine, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Bela Bozoky
- Department of Clinical Pathology/Cytology, Karolinska University Hospital, Huddinge, Sweden
| | - Jan Kehr
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Elvar Theodorsson
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, 58285 Linköping, Sweden
| | - Jose A Cancelas
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
- Hoxworth Blood Center, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0055, USA
| | - Boris Mravec
- Biomedical Research Center, Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovak Republic
- Institute of Physiology, Faculty of Medicine, Comenius University in Bratislava, Slovak Republic
| | - Carl Jorns
- PO Transplantation, Karolinska University Hospital Huddinge, 141 52 Stockholm, Sweden
| | - Ewa Ellis
- Department of Transplantation Surgery and Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska University Hospital, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Jan Mulder
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Mathias Uhlén
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
- Science for Life Laboratory, Royal Institute of Technology, 10691 Stockholm, Sweden
| | - Christina Bark
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
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14
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Ibrahim SH. Sinusoidal endotheliopathy in nonalcoholic steatohepatitis: therapeutic implications. Am J Physiol Gastrointest Liver Physiol 2021; 321:G67-G74. [PMID: 34037463 PMCID: PMC8321796 DOI: 10.1152/ajpgi.00009.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Liver sinusoidal endothelial cells (LSECs) are distinct subtypes of endothelial cells lining a low flow vascular bed at the interface of the liver parenchyma and the circulating immune cells and soluble factors. Emerging literature implicates LSEC in the pathogenesis and progression of nonalcoholic fatty liver disease (NAFLD). During the evolution of NAFLD, LSEC dysfunction ensues. LSECs undergo morphological and functional transformation known as "capillarization," as well as a pathogenic increase in surface adhesion molecules expression, referred to in this review as "endotheliopathy." LSECs govern the composition of hepatic immune cell populations in nonalcoholic steatohepatis (NASH) by mediating leukocyte subset adhesion through specific combinations of activated adhesion molecules and secreted chemokines. Moreover, extracellular vesicles released by hepatocyte under lipotoxic stress in NASH act as a catalyst for the inflammatory response and promote immune cell chemotaxis and adhesion. In the current review, we highlight leukocyte adhesion to LSEC as an initiating event in the sterile inflammatory response in NASH. We discuss preclinical studies targeting immune cells adhesion in NASH mouse models and potential therapeutic anti-inflammatory strategies for human NASH.
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Affiliation(s)
- Samar H. Ibrahim
- 1Division of Gastroenterology & Hepatology, Mayo Clinic, Rochester, Minnesota,2Division of Pediatric Gastroenterology, Mayo Clinic, Rochester, Minnesota
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15
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Abstract
Liver sinusoidal endothelial cells (LSECs) form the wall of the hepatic sinusoids. Unlike other capillaries, they lack an organized basement membrane and have cytoplasm that is penetrated by open fenestrae, making the hepatic microvascular endothelium discontinuous. LSECs have essential roles in the maintenance of hepatic homeostasis, including regulation of the vascular tone, inflammation and thrombosis, and they are essential for control of the hepatic immune response. On a background of acute or chronic liver injury, LSECs modify their phenotype and negatively affect neighbouring cells and liver disease pathophysiology. This Review describes the main functions and phenotypic dysregulations of LSECs in liver diseases, specifically in the context of acute injury (ischaemia-reperfusion injury, drug-induced liver injury and bacterial and viral infection), chronic liver disease (metabolism-associated liver disease, alcoholic steatohepatitis and chronic hepatotoxic injury) and hepatocellular carcinoma, and provides a comprehensive update of the role of LSECs as therapeutic targets for liver disease. Finally, we discuss the open questions in the field of LSEC pathobiology and future avenues of research.
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16
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Oldenburger A, Birk G, Schlepütz M, Broermann A, Stierstorfer B, Pullen SS, Rippmann JF. Modulation of vascular contraction via soluble guanylate cyclase signaling in a novel ex vivo method using rat precision-cut liver slices. Pharmacol Res Perspect 2021; 9:e00768. [PMID: 34014044 PMCID: PMC8135082 DOI: 10.1002/prp2.768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 01/05/2023] Open
Abstract
Fibrotic processes in the liver of non-alcoholic steatohepatitis (NASH) patients cause microcirculatory dysfunction in the organ which increases blood vessel resistance and causes portal hypertension. Assessing blood vessel function in the liver is challenging, necessitating the development of novel methods in normal and fibrotic tissue that allow for drug screening and translation toward pre-clinical settings. Cultures of precision cut liver slices (PCLS) from normal and fibrotic rat livers were used for blood vessel function analysis. Live recording of vessel diameter was used to assess the response to endothelin-1, serotonin and soluble guanylate cyclase (sGC) activation. A cascade of contraction and relaxation events in response to serotonin, endothelin-1, Ketanserin and sGC activity could be established using vessel diameter analysis of rat PCLS. Both the sGC activator BI 703704 and the sGC stimulator Riociguat prevented serotonin-induced contraction in PCLS from naive rats. By contrast, PCLS cultures from the rat CCl4 NASH model were only responsive to the sGC activator, thus establishing that the sGC enzyme is rendered non-responsive to nitric oxide under oxidative stress found in fibrotic livers. The role of the sGC pathway for vessel relaxation of fibrotic liver tissue was identified in our model. The obtained data shows that the inhibitory capacities on vessel contraction of sGC compounds can be translated to published preclinical data. Altogether, this novel ex vivo PCLS method allows for the differentiation of drug candidates and the translation of therapeutic approaches towards the clinical use.
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Affiliation(s)
- Anouk Oldenburger
- CardioMetabolic Diseases ResearchBoehringer Ingelheim Pharma GmbH & Co. KGBiberach a.d. RissGermany
| | - Gerald Birk
- Target Discovery SciencesBoehringer Ingelheim Pharma GmbH & Co. KGBiberach an der RissGermany
| | - Marco Schlepütz
- Immunology and Respiratory Diseases ResearchBoehringer Ingelheim Pharma GmbH & Co. KGBiberach an der RissGermany
| | - Andre Broermann
- CardioMetabolic Diseases ResearchBoehringer Ingelheim Pharma GmbH & Co. KGBiberach a.d. RissGermany
| | - Birgit Stierstorfer
- Target Discovery SciencesBoehringer Ingelheim Pharma GmbH & Co. KGBiberach an der RissGermany
| | - Steven S. Pullen
- CardioMetabolic Diseases ResearchBoehringer Ingelheim Pharmaceuticals, IncRidgefieldCTUSA
| | - Jörg F. Rippmann
- Cancer Immunology+Immune ModulationBoehringer Ingelheim Pharma GmbH & Co. KGBiberach a.d. RissGermany
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17
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Kmeid M, Liu X, Ballentine S, Lee H. Idiopathic Non-Cirrhotic Portal Hypertension and Porto-Sinusoidal Vascular Disease: Review of Current Data. Gastroenterology Res 2021; 14:49-65. [PMID: 34007347 PMCID: PMC8110235 DOI: 10.14740/gr1376] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 03/30/2021] [Indexed: 12/29/2022] Open
Abstract
Idiopathic non-cirrhotic portal hypertension (INCPH) is a clinicopathologic disease entity characterized by the presence of clinical signs and symptoms of portal hypertension (PH) in the absence of liver cirrhosis or known risk factors accountable for PH. Multiple hematologic, immune-related, infectious, hereditary and metabolic risk factors have been associated with this disorder. Still, the exact etiopathogenesis is largely unknown. The recently proposed porto-sinusoidal vascular disease (PSVD) scheme broadens the spectrum of the disease by also including patients without clinical PH who are found to have similar histopathologic findings on core liver biopsies. Three histomorphologic lesions have been identified as specific for PSVD to include obliterative portal venopathy, nodular regenerative hyperplasia and incomplete septal cirrhosis/fibrosis. However, these findings are often subtle, under-recognized and subjective with low interobserver agreement among pathologists. Additionally, the natural history of the subclinical forms of the disease remains unexplored. The clinical course is more favorable compared to cirrhosis patients, especially in the absence of clinical PH or liver dysfunction. There are no universally accepted guidelines in regard to diagnosis and treatment of INCPH/PSVD. Hence, this review emphasizes the need to raise awareness of this entity by highlighting its complex pathophysiology and clinicopathologic associations. Lastly, formulation of standardized diagnostic criteria with clinical validation is necessary to avoid misclassifying vascular diseases of the liver and to develop and implement targeted therapeutic strategies.
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Affiliation(s)
- Michel Kmeid
- Department of Pathology and Laboratory Medicine, Albany Medical Center, Albany, NY, USA
| | - Xiuli Liu
- Department of Pathology and Laboratory Medicine, University of Florida at Gainesville, FL, USA
| | - Samuel Ballentine
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Hwajeong Lee
- Department of Pathology and Laboratory Medicine, Albany Medical Center, Albany, NY, USA
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18
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Affiliation(s)
- Sven Francque
- Department of Gastroenterology and Hepatology Antwerp University Hospital Antwerp Belgium.,Faculty of Medicine and Health Sciences Laboratory of Experimental Medicine and Paediatrics University of Antwerp Antwerp Belgium.,Faculty of Medicine and Health Sciences InflaMed Consortium of Excellence University of Antwerp Antwerp Belgium
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19
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Soret PA, Magusto J, Housset C, Gautheron J. In Vitro and In Vivo Models of Non-Alcoholic Fatty Liver Disease: A Critical Appraisal. J Clin Med 2020; 10:jcm10010036. [PMID: 33374435 PMCID: PMC7794936 DOI: 10.3390/jcm10010036] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD), including non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH), represents the hepatic manifestation of obesity and metabolic syndrome. Due to the spread of the obesity epidemic, NAFLD is becoming the most common chronic liver disease and one of the principal indications for liver transplantation. However, no pharmacological treatment is currently approved to prevent the outbreak of NASH, which leads to fibrosis and cirrhosis. Preclinical research is required to improve our knowledge of NAFLD physiopathology and to identify new therapeutic targets. In the present review, we summarize advances in NAFLD preclinical models from cellular models, including new bioengineered platforms, to in vivo models, with a particular focus on genetic and dietary mouse models. We aim to discuss the advantages and limits of these different models.
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Affiliation(s)
- Pierre-Antoine Soret
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université, Inserm, 75012 Paris, France; (P.-A.S.); (J.M.); (C.H.)
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hepatology Department, Reference Center for Inflammatory Biliary Diseases and Autoimmune Hepatitis, Saint-Antoine Hospital, 75012 Paris, France
| | - Julie Magusto
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université, Inserm, 75012 Paris, France; (P.-A.S.); (J.M.); (C.H.)
- Institute of Cardiometabolism and Nutrition (ICAN), Sorbonne Université, Inserm, AP-HP, 75013 Paris, France
| | - Chantal Housset
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université, Inserm, 75012 Paris, France; (P.-A.S.); (J.M.); (C.H.)
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hepatology Department, Reference Center for Inflammatory Biliary Diseases and Autoimmune Hepatitis, Saint-Antoine Hospital, 75012 Paris, France
- Institute of Cardiometabolism and Nutrition (ICAN), Sorbonne Université, Inserm, AP-HP, 75013 Paris, France
| | - Jérémie Gautheron
- Centre de Recherche Saint-Antoine (CRSA), Sorbonne Université, Inserm, 75012 Paris, France; (P.-A.S.); (J.M.); (C.H.)
- Institute of Cardiometabolism and Nutrition (ICAN), Sorbonne Université, Inserm, AP-HP, 75013 Paris, France
- Correspondence:
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20
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Verlinden W, Van Mieghem E, Depauw L, Vanwolleghem T, Vonghia L, Weyler J, Driessen A, Callens D, Roosens L, Dirinck E, Verrijken A, Gaal LV, Francque S. Non-Alcoholic Steatohepatitis Decreases Microsomal Liver Function in the Absence of Fibrosis. Biomedicines 2020; 8:E546. [PMID: 33261113 PMCID: PMC7760673 DOI: 10.3390/biomedicines8120546] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/23/2020] [Accepted: 11/26/2020] [Indexed: 12/21/2022] Open
Abstract
The incidence of non-alcoholic fatty liver disease (NAFLD) is rising across the globe, with the presence of steatohepatitis leading to a more aggressive clinical course. Currently, the diagnosis of non-alcoholic steatohepatitis (NASH) is based on histology, though with the high prevalence of NAFLD, a non-invasive method is needed. The 13C-aminopyrine breath test (ABT) evaluates the microsomal liver function and could be a potential candidate. We aimed to evaluate a potential change in liver function in NASH patients and to evaluate the diagnostic power of ABT to detect NASH. We performed a retrospective analysis on patients suspected of NAFLD who underwent a liver biopsy and ABT. 440 patients were included. ABT did not decrease in patients with isolated liver steatosis but decreased significantly in the presence of NASH without fibrosis and decreased even further with the presence of significant fibrosis. The predictive power of ABT as a single test for NASH was low but improved in combination with ALT and ultrasonographic steatosis. We conclude that microsomal liver function of patients with NASH is significantly decreased, even in the absence of fibrosis. The ABT is thus a valuable tool in assessing the presence of NASH; and could be used as a supplementary diagnostic tool in clinical practice.
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Affiliation(s)
- Wim Verlinden
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, 2650 Antwerp, Belgium
| | - Eugénie Van Mieghem
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
| | - Laura Depauw
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
| | - Thomas Vanwolleghem
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, 2650 Antwerp, Belgium
| | - Luisa Vonghia
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, 2650 Antwerp, Belgium
| | - Jonas Weyler
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, 2650 Antwerp, Belgium
| | - Ann Driessen
- Department of Pathology, Antwerp University Hospital, 2650 Antwerp, Belgium;
| | - Dirk Callens
- Department of Clinical Biology, Antwerp University Hospital, 2650 Antwerp, Belgium; (D.C.); (L.R.)
| | - Laurence Roosens
- Department of Clinical Biology, Antwerp University Hospital, 2650 Antwerp, Belgium; (D.C.); (L.R.)
| | - Eveline Dirinck
- Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, 2650 Antwerp, Belgium; (E.D.); (A.V.); (L.V.G.)
| | - An Verrijken
- Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, 2650 Antwerp, Belgium; (E.D.); (A.V.); (L.V.G.)
| | - Luc Van Gaal
- Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, 2650 Antwerp, Belgium; (E.D.); (A.V.); (L.V.G.)
| | - Sven Francque
- Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology and Hepatology, University of Antwerp, 2610 Antwerp, Belgium; (E.V.M.); (L.D.); (T.V.); (L.V.); (J.W.)
- Department of Gastroenterology and Hepatology, Antwerp University Hospital, 2650 Antwerp, Belgium
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21
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Barberá A, Raurell I, García-Lezana T, Torres-Arauz M, Bravo M, Hide D, Gil M, Salcedo MT, Genescà J, Martell M, Augustin S. Steatosis as main determinant of portal hypertension through a restriction of hepatic sinusoidal area in a dietary rat nash model. Liver Int 2020; 40:2732-2743. [PMID: 32770818 DOI: 10.1111/liv.14632] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/10/2020] [Accepted: 08/02/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS Portal hypertension (PH) can be present in pre-cirrhotic stages, even in absence of fibrosis in non-alcoholic steatohepatitis (NASH) patients. Liver endothelial dysfunction (ED) has been shown as responsible for this effect in short-term dietary animal models. We evaluated the persistence of PH and underlying mechanisms in a long-term rat model of NASH. METHODS Sprague-Dawley rats were fed 8 or 36 weeks with control diet or high-fat high-glucose/fructose diet. Metabolic parameters, histology, ED and haemodynamics were characterized. Structural characteristics of liver sections were analysed using image analysis. RESULTS Both interventions reproduced NASH histological hallmarks (with steatosis being particularly increased at 36 weeks), but neither induced fibrosis. The 36-week intervention induced a significant increase in portal pressure (PP) compared to controls (12.1 vs 8.7 mmHg, P < .001) and the 8-week model (10.7 mmHg, P = .006), but all features of ED were normalized at 36 weeks. Image analysis revealed that the increased steatosis at 36-week was associated to an increase in hepatocyte area and a significant decrease in the sinusoidal area, which was inversely correlated with PP. The analysis provided a critical sinusoidal area above which animals were protected from developing PH and below which sinusoidal flux was compromised and PP started to increase. CONCLUSION Liver steatosis per se (in absence of fibrosis) can induce PH through a decrease in the sinusoidal area secondary to the increase in hepatocyte area in a long-term diet-induced rat model of NASH. Image analysis of the sinusoidal area might predict the presence of PH.
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Affiliation(s)
- Aurora Barberá
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | - Imma Raurell
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | | | - Manuel Torres-Arauz
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | - Miren Bravo
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | - Diana Hide
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | - Mar Gil
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain
| | - María Teresa Salcedo
- Pathology Department, Hospital Universitari Vall d´Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Joan Genescà
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain.,Centro De Investigación Biomédica En Red De Enfermedades Hepáticas y Digestivas, Instituto De Salud Carlos III, Madrid, Spain
| | - María Martell
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain.,Centro De Investigación Biomédica En Red De Enfermedades Hepáticas y Digestivas, Instituto De Salud Carlos III, Madrid, Spain
| | - Salvador Augustin
- Liver Unit, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, Barcelona, Spain, Barcelona, Spain.,Centro De Investigación Biomédica En Red De Enfermedades Hepáticas y Digestivas, Instituto De Salud Carlos III, Madrid, Spain
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22
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Nevzorova YA, Boyer-Diaz Z, Cubero FJ, Gracia-Sancho J. Animal models for liver disease - A practical approach for translational research. J Hepatol 2020; 73:423-440. [PMID: 32330604 DOI: 10.1016/j.jhep.2020.04.011] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/06/2020] [Accepted: 04/06/2020] [Indexed: 12/11/2022]
Abstract
Animal models are crucial for improving our understanding of human pathogenesis, enabling researchers to identify therapeutic targets and test novel drugs. In the current review, we provide a comprehensive summary of the most widely used experimental models of chronic liver disease, starting from early stages of fatty liver disease (non-alcoholic and alcoholic) to steatohepatitis, advanced cirrhosis and end-stage primary liver cancer. We focus on aspects such as reproducibility and practicality, discussing the advantages and weaknesses of available models for researchers who are planning to perform animal studies in the near future. Additionally, we summarise current and prospective models based on human tissue bioengineering.
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Affiliation(s)
- Yulia A Nevzorova
- Department of Genetics, Physiology and Microbiology, Faculty of Biology, Complutense University, Madrid, Spain; 12 de Octubre Health Research Institute (imas12), Madrid, Spain; Department of Internal Medicine III, University Hospital RWTH Aachen, Aachen, Germany
| | - Zoe Boyer-Diaz
- Liver Vascular Biology Research Group, Barcelona Hepatic Hemodynamic Unit, IDIBAPS Biomedical Research Institute, Barcelona, Spain; Barcelona Liver Bioservices, Barcelona, Spain
| | - Francisco Javier Cubero
- 12 de Octubre Health Research Institute (imas12), Madrid, Spain; Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, Madrid, Spain.
| | - Jordi Gracia-Sancho
- Liver Vascular Biology Research Group, Barcelona Hepatic Hemodynamic Unit, IDIBAPS Biomedical Research Institute, Barcelona, Spain; Barcelona Liver Bioservices, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Madrid, Spain; Hepatology, Department of Biomedical Research, University of Bern, Bern, Switzerland.
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23
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Ryou M, Stylopoulos N, Baffy G. Nonalcoholic fatty liver disease and portal hypertension. EXPLORATION OF MEDICINE 2020; 1:149-169. [PMID: 32685936 DOI: 10.37349/emed.2020.00011] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a substantial and growing problem worldwide and has become the second most common indication for liver transplantation as it may progress to cirrhosis and develop complications from portal hypertension primarily caused by advanced fibrosis and erratic tissue remodeling. However, elevated portal venous pressure has also been detected in experimental models of fatty liver and in human NAFLD when fibrosis is far less advanced and cirrhosis is absent. Early increases in intrahepatic vascular resistance may contribute to the progression of liver disease. Specific pathophenotypes linked to the development of portal hypertension in NAFLD include hepatocellular lipid accumulation and ballooning injury, capillarization of liver sinusoidal endothelial cells, enhanced contractility of hepatic stellate cells, activation of Kupffer cells and pro-inflammatory pathways, adhesion and entrapment of recruited leukocytes, microthrombosis, angiogenesis and perisinusoidal fibrosis. These pathological events are amplified in NAFLD by concomitant visceral obesity, insulin resistance, type 2 diabetes and dysbiosis, promoting aberrant interactions with adipose tissue, skeletal muscle and gut microbiota. Measurement of the hepatic venous pressure gradient by retrograde insertion of a balloon-tipped central vein catheter is the current reference method for predicting outcomes of cirrhosis associated with clinically significant portal hypertension and guiding interventions. This invasive technique is rarely considered in the absence of cirrhosis where currently available clinical, imaging and laboratory correlates of portal hypertension may not reflect early changes in liver hemodynamics. Availability of less invasive but sufficiently sensitive methods for the assessment of portal venous pressure in NAFLD remains therefore an unmet need. Recent efforts to develop new biomarkers and endoscopy-based approaches such as endoscopic ultrasound-guided measurement of portal pressure gradient may help achieve this goal. In addition, cellular and molecular targets are being identified to guide emerging therapies in the prevention and management of portal hypertension.
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Affiliation(s)
- Marvin Ryou
- Department of Medicine, Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Nicholas Stylopoulos
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA.,The Broad Institute of MIT and Harvard, Cambridge MA
| | - Gyorgy Baffy
- Department of Medicine, Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.,Department of Medicine, VA Boston Healthcare System, Harvard Medical School, Boston, MA
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24
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Clough GF, Chipperfield AJ, Thanaj M, Scorletti E, Calder PC, Byrne CD. Dysregulated Neurovascular Control Underlies Declining Microvascular Functionality in People With Non-alcoholic Fatty Liver Disease (NAFLD) at Risk of Liver Fibrosis. Front Physiol 2020; 11:551. [PMID: 32581841 PMCID: PMC7283580 DOI: 10.3389/fphys.2020.00551] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 04/30/2020] [Indexed: 11/30/2022] Open
Abstract
Background/Aims Increasing evidence shows that non-alcoholic fatty liver disease (NAFLD) is associated with dysregulation of microvascular perfusion independently of established cardio-metabolic risk factors. We investigated whether hepatic manifestations of NAFLD such as liver fibrosis and liver fat are associated with microvascular hemodynamics through dysregulation of neurovascular control. Methods Microvascular dilator (post-occlusive reactive hyperemia) and sympathetically mediated constrictor (deep inspiratory breath-hold) responses were measured at the forearm and finger, respectively, using laser Doppler fluximetry. Non-linear complexity-based analysis was used to assess the information content and variability of the resting blood flux (BF) signals, attributable to oscillatory flow-motion activity, and over multiple sampling frequencies. Results Measurements were made in 189 adults (113 men) with NAFLD, with (n = 65) and without (n = 124) type 2 diabetes mellitus (T2DM), age = 50.9 ± 11.7 years (mean ± SD). Microvascular dilator and constrictor capacity were both negatively associated with age (r = −0.178, p = 0.014, and r = −0.201, p = 0.007, respectively) and enhanced liver fibrosis (ELF) score (r = −0.155, p = 0.038 and r = −0.418, p < 0.0001, respectively). There was no association with measures of liver fat, obesity or T2DM. Lempel-Ziv complexity (LZC) and sample entropy (SE) of the BF signal measured at the two skin sites were associated negatively with age (p < 0.01 and p < 0.001) and positively with ELF score (p < 0.05 and p < 0.0001). In individuals with an ELF score ≥7.8 the influence of both neurogenic and respiratory flow-motion activity on LZC was up-rated (p < 0.0001). Conclusion Altered microvascular network functionality occurs in adults with NAFLD suggesting a mechanistic role for dysregulated neurovascular control in individuals at risk of severe liver fibrosis.
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Affiliation(s)
- Geraldine F Clough
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Andrew J Chipperfield
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom
| | - Marjola Thanaj
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom
| | - Eleonora Scorletti
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.,National Institute for Health Research Southampton Biomedical Research Centre, University of Southampton, University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom.,Department of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Philip C Calder
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.,National Institute for Health Research Southampton Biomedical Research Centre, University of Southampton, University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom
| | - Christopher D Byrne
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.,National Institute for Health Research Southampton Biomedical Research Centre, University of Southampton, University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom
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25
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Cremonese C, Schierwagen R, Uschner FE, Torres S, Tyc O, Ortiz C, Schulz M, Queck A, Kristiansen G, Bader M, Sauerbruch T, Weiskirchen R, Walther T, Trebicka J, Klein S. Short-Term Western Diet Aggravates Non-Alcoholic Fatty Liver Disease (NAFLD) With Portal Hypertension in TGR(mREN2)27 Rats. Int J Mol Sci 2020; 21:E3308. [PMID: 32392802 PMCID: PMC7246932 DOI: 10.3390/ijms21093308] [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: 04/03/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 12/14/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is gaining in importance and is linked to obesity. Especially, the development of fibrosis and portal hypertension in NAFLD patients requires treatment. Transgenic TGR(mREN2)27 rats overexpressing mouse renin spontaneously develop NAFLD with portal hypertension but without obesity. This study investigated the additional role of obesity in this model on the development of portal hypertension and fibrosis. Obesity was induced in twelve-week old TGR(mREN2)27 rats after receiving Western diet (WD) for two or four weeks. Liver fibrosis was assessed using standard techniques. Hepatic expression of transforming growth factor-β1 (TGF-β1), collagen type Iα1, α-smooth muscle actin, and the macrophage markers Emr1, as well as the chemoattractant Ccl2, interleukin-1β (IL1β) and tumor necrosis factor-α (TNFα) were analyzed. Assessment of portal and systemic hemodynamics was performed using the colored microsphere technique. As expected, WD induced obesity and liver fibrosis as confirmed by Sirius Red and Oil Red O staining. The expression of the monocyte-macrophage markers, Emr1, Ccl2, IL1β and TNFα were increased during feeding of WD, indicating infiltration of macrophages into the liver, even though this increase was statistically not significant for the EGF module-containing mucin-like receptor (Emr1) mRNA expression levels. Of note, portal pressure increased with the duration of WD compared to animals that received a normal chow. Besides obesity, WD feeding increased systemic vascular resistance reflecting systemic endothelial and splanchnic vascular dysfunction. We conclude that transgenic TGR(mREN2)27 rats are a suitable model to investigate NAFLD development with liver fibrosis and portal hypertension. Tendency towards elevated expression of Emr1 is associated with macrophage activity point to a significant role of macrophages in NAFLD pathogenesis, probably due to a shift of the renin-angiotensin system towards a higher activation of the classical pathway. The hepatic injury induced by WD in TGR(mREN2)27 rats is suitable to evaluate different stages of fibrosis and portal hypertension in NAFLD with obesity.
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Affiliation(s)
- Carla Cremonese
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Robert Schierwagen
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Frank Erhard Uschner
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Sandra Torres
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Olaf Tyc
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Cristina Ortiz
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Martin Schulz
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Alexander Queck
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
| | - Glen Kristiansen
- Institute for Pathology, University of Bonn, 53127 Bonn, Germany;
| | - Michael Bader
- Max Delbrück Center for Molecular Medicine, 13092 Berlin, Germany;
| | - Tilman Sauerbruch
- Department of Internal Medicine I, University Hospital of Bonn, 53127 Bonn, Germany;
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen, 52074 Aachen, Germany;
| | - Thomas Walther
- Department of Pharmacology and Therapeutics, University College Cork, T12 YN60 Cork, Ireland;
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, 17489 Greifswald, Germany
| | - Jonel Trebicka
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
- Institute for Bioengineering of Catalonia, 08028 Barcelona, Spain
- European Foundation for the Study of Chronic Liver Failure, 08021 Barcelona, Spain
- Faculty of Health Sciences, University of Southern Denmark, 5000 Odense, Denmark
| | - Sabine Klein
- Department of Internal Medicine I, Goethe University Frankfurt, 60323 Frankfurt, Germany; (C.C.); (R.S.); (F.E.U.); (S.T.); (O.T.); (C.O.); (M.S.); (A.Q.); (S.K.)
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26
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Semmler G, Scheiner B, Schwabl P, Bucsics T, Paternostro R, Chromy D, Stättermayer AF, Trauner M, Mandorfer M, Ferlitsch A, Reiberger T. The impact of hepatic steatosis on portal hypertension. PLoS One 2019; 14:e0224506. [PMID: 31693695 PMCID: PMC6834246 DOI: 10.1371/journal.pone.0224506] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/15/2019] [Indexed: 12/20/2022] Open
Abstract
Background and aims Studies in animal models have suggested that hepatic steatosis impacts on portal pressure, potentially by inducing liver sinusoidal endothelial dysfunction and thereby increasing intrahepatic resistance. Thus, we aimed to evaluate the impact of hepatic steatosis on hepatic venous pressure gradient (HVPG) in patients with chronic liver disease. Method 261 patients undergoing simultaneous HVPG measurements and controlled attenuation parameter (CAP)-based steatosis assessment were included in this retrospective study. Results The majority of patients had cirrhosis (n = 205; 78.5%) and n = 191 (73.2%) had clinically significant portal hypertension (CSPH; HVPG≥10mmHg). Hepatic steatosis (S1/2/3; CAP ≥248dB/m) was present in n = 102 (39.1%). Overall, HVPG was comparable between patients with vs. without hepatic steatosis (15.5±7.5 vs. 14.8±7.7mmHg; p = 0.465). Neither in patients with HVPG (<6mmHg; p = 0.371) nor in patients with mild portal hypertension (HVPG 6–9mmHg; p = 0.716) or CSPH (HVPG≥10mmHg; p = 0.311) any correlation between CAP and HVPG was found. Interestingly, in patients with liver fibrosis F2/3, there was a negative correlation between CAP and HVPG (Pearson’s ρ:-0.522; p≤0.001). In multivariate analysis, higher CAP was an independent ‘protective’ factor for the presence of CSPH (odds ratio [OR] per 10dB/m: 0.92, 95% confidence interval [CI]:0.85–1.00; p = 0.045), while liver stiffness was associated with the presence of CSPH (OR per kPa: 1.26, 95%CI: 1.17–1.36; p≤0.001). In 78 patients, in whom liver biopsy was performed, HVPG was neither correlated with percentage of histological steatosis (p = 0.714) nor with histological steatosis grade (p = 0.957). Conclusion Hepatic steatosis, as assessed by CAP and liver histology, did not impact on HVPG in our cohort comprising a high proportion of patients with advanced chronic liver disease. However, high CAP values (i.e. pronounced hepatic steatosis) might lead to overestimation of liver fibrosis by ‘artificially’ increasing transient elastography-based liver stiffness measurements.
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Affiliation(s)
- Georg Semmler
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Bernhard Scheiner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Philipp Schwabl
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Theresa Bucsics
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Rafael Paternostro
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - David Chromy
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Albert Friedrich Stättermayer
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Mattias Mandorfer
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Arnulf Ferlitsch
- Department of Internal Medicine I, Hospital of St. John of God, Vienna, Austria
| | - Thomas Reiberger
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
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27
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The effects of hepatic steatosis on thromboxane A2 induced portal hypertension. GASTROENTEROLOGIA Y HEPATOLOGIA 2019; 42:534-541. [DOI: 10.1016/j.gastrohep.2019.03.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/19/2019] [Accepted: 03/29/2019] [Indexed: 01/09/2023]
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28
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Klein S, Kleine CE, Pieper A, Granzow M, Gautsch S, Himmit M, Kahrmann K, Schierwagen R, Uschner FE, Magdaleno F, Naoum ME, Kristiansen G, Walther T, Bader M, Sauerbruch T, Trebicka J. TGR(mREN2)27 rats develop non-alcoholic fatty liver disease-associated portal hypertension responsive to modulations of Janus-kinase 2 and Mas receptor. Sci Rep 2019; 9:11598. [PMID: 31406138 PMCID: PMC6690919 DOI: 10.1038/s41598-019-48024-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 07/29/2019] [Indexed: 12/14/2022] Open
Abstract
Prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing. Resulting fibrosis and portal hypertension, as a possible secondary event, may necessitate treatment. Overexpression of mouse renin in the transgenic rat model, TGR(mREN2)27, leads to spontaneous development of NAFLD. Therefore, we used TGR(mREN2)27 rats as a model of NAFLD where we hypothesized increased susceptibility and investigated fibrosis and portal hypertension and associated pathways. 12-week old TGR(mREN2)27 rats received either cholestatic (BDL) or toxic injury (CCl4 inhalation). Portal and systemic hemodynamic assessments were performed using microsphere technique with and without injection of the Janus-Kinase 2 (JAK2) inhibitor AG490 or the non-peptidic Ang(1-7) agonist, AVE0991. The extent of liver fibrosis was assessed in TGR(mREN2)27 and wild-type rats using standard techniques. Protein and mRNA levels of profibrotic, renin-angiotensin system components were assessed in liver and primary hepatic stellate cells (HSC) and hepatocytes. TGR(mREN2)27 rats developed spontaneous, but mild fibrosis and portal hypertension due to the activation of the JAK2/Arhgef1/ROCK pathway. AG490 decreased migration of HSC and portal pressure in isolated liver perfusions and in vivo. Fibrosis or portal hypertension after cholestatic (BDL) or toxic injury (CCl4) was not aggravated in TGR(mREN2)27 rats, probably due to decreased mouse renin expression in hepatocytes. Interestingly, portal hypertension was even blunted in TGR(mREN2)27 rats (with or without additional injury) by AVE0991. TGR(mREN2)27 rats are a suitable model of spontaneous liver fibrosis and portal hypertension but not with increased susceptibility to liver damage. After additional injury, the animals can be used to evaluate novel therapeutic strategies targeting Mas.
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Affiliation(s)
- Sabine Klein
- Department of Internal Medicine I, Goethe University Frankfurt, Frankfurt, Germany
| | | | - Andrea Pieper
- House for Experimental Therapy, University of Bonn, Bonn, Germany
| | - Michaela Granzow
- Department of Internal Medicine I, University of Bonn, Bonn, Germany
| | - Sebastian Gautsch
- Department of Internal Medicine I, University of Bonn, Bonn, Germany
| | - Mimoun Himmit
- Department of Internal Medicine I, University of Bonn, Bonn, Germany
| | | | - Robert Schierwagen
- Department of Internal Medicine I, Goethe University Frankfurt, Frankfurt, Germany
| | - Frank Erhard Uschner
- Department of Internal Medicine I, Goethe University Frankfurt, Frankfurt, Germany
| | | | | | | | - Thomas Walther
- Department of Pharmacology and Therapeutics, University College Cork, Cork, Ireland.,Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, Greifswald, Germany
| | - Michael Bader
- Berlin Institute of Health (BIH), Berlin, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Institute for Biology, University of Lübeck, Lübeck, Germany.,Charité-University Medicine Berlin, Berlin, Germany.,Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Tilman Sauerbruch
- Department of Internal Medicine I, University of Bonn, Bonn, Germany
| | - Jonel Trebicka
- Department of Internal Medicine I, Goethe University Frankfurt, Frankfurt, Germany. .,European Foundation for the Study of Chronic Liver Failure, Barcelona, Spain. .,Institute for Bioengineering of Catalonia, Barcelona, Spain. .,Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.
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29
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Pavlovic N, Rani B, Gerwins P, Heindryckx F. Platelets as Key Factors in Hepatocellular Carcinoma. Cancers (Basel) 2019; 11:cancers11071022. [PMID: 31330817 PMCID: PMC6678690 DOI: 10.3390/cancers11071022] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/08/2019] [Accepted: 07/18/2019] [Indexed: 12/21/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a primary liver cancer that usually develops in the setting of chronic inflammation and liver damage. The hepatic microenvironment plays a crucial role in the disease development, as players such as hepatic stellate cells, resident liver macrophages (Kupffer cells), endothelial cells, extracellular matrix, and a variety of immune cells interact in highly complex and intertwined signaling pathways. A key factor in these cross-talks are platelets, whose role in cancer has gained growing evidence in recent years. Platelets have been reported to promote HCC cell proliferation and invasion, but their involvement goes beyond the direct effect on tumor cells, as they are known to play a role in pro-fibrinogenic signaling and the hepatic immune response, as well as in mediating interactions between these factors in the stroma. Anti-platelet therapy has been shown to ameliorate liver injury and improve the disease outcome. However, platelets have also been shown to play a crucial role in liver regeneration after organ damage. Therefore, the timing and microenvironmental setting need to be kept in mind when assessing the potential effect and therapeutic value of platelets in the disease progression, while further studies are needed for understanding the role of platelets in patients with HCC.
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Affiliation(s)
- Natasa Pavlovic
- Department of Medical Cell Biology, Uppsala University, Box 571, Husargatan 3, 75-431 Uppsala, Sweden
| | - Bhavna Rani
- Department of Medical Cell Biology, Uppsala University, Box 571, Husargatan 3, 75-431 Uppsala, Sweden
| | - Pär Gerwins
- Department of Medical Cell Biology, Uppsala University, Box 571, Husargatan 3, 75-431 Uppsala, Sweden
- Department of Radiology, Uppsala University Hospital, Sjukhusvägen 85, 751-85 Uppsala, Sweden
| | - Femke Heindryckx
- Department of Medical Cell Biology, Uppsala University, Box 571, Husargatan 3, 75-431 Uppsala, Sweden.
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30
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Lyle AN, Taylor WR. The pathophysiological basis of vascular disease. J Transl Med 2019; 99:284-289. [PMID: 30755702 DOI: 10.1038/s41374-019-0192-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 01/08/2019] [Indexed: 12/12/2022] Open
Affiliation(s)
- Alicia N Lyle
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - W Robert Taylor
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA. .,Division of Cardiology, Atlanta Veterans Affairs Medical Center, Decatur, GA, USA. .,Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA.
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31
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The potential role of vascular alterations and subsequent impaired liver blood flow and hepatic hypoxia in the pathophysiology of non-alcoholic steatohepatitis. Med Hypotheses 2018; 122:188-197. [PMID: 30593409 DOI: 10.1016/j.mehy.2018.11.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 11/21/2018] [Indexed: 12/12/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) covers a spectrum of disease ranging from steatosis to steatohepatitis (NASH) and fibrosis, but the underlying pathophysiological mechanisms remain largely unknown. As there is currently no approved pharmacological therapy and the prevalence of NAFLD keeps increasing, understanding of its pathophysiology is crucial. We hypothesise that vascular alterations in early NAFLD play a role in the progression of the disease by inducing an increased intrahepatic vascular resistance and consequently relative hypoxia in the liver. Evidence of the detrimental effects of hypoxia in NAFLD has already been observed in liver surgery, where the outcomes of steatotic livers after ischaemia-reperfusion are worse than in healthy livers, and in obstructive sleep apnoea, which is an independent risk factor of NAFLD. Moreover, early histological damage in NAFLD is situated in the pericentral zone, which is also the first zone to be affected by a decreased oxygen tension because of the unique hepatic vacsular anatomy that causes the pericentral oxygen tension to be the lowest. Angiogenesis is also a characteristic of NAFLD, driven by hypoxia-induced mechanisms, as demonstrated in both animal models and in humans with NAFLD. Relative hypoxia is most probably induced by impaired blood flow to the liver, caused by increased intrahepatic vascular resistance. An increased intrahepatic vascular resistance early in the development of disease has been convincingly demonstrated in several animal models of NAFLD, whereas an increased portal pressure, a consequence of increased intrahepatic vascular resistance, has been proven in patients with NAFLD. Animal studies demonstrated a decreased intrahepatic effect of vasodilators and an increased reactivity to vasoconstrictors that results in an increased intrahepatic vascular resistance, thus the presence of a functional component. Pharmacological products that target vasoregulation can hence improve the intrahepatic vascular resistance and this might prevent or reverse progression of NAFLD, representing an important therapeutic option to study. Some of the drugs currently under evaluation in clinical trials for NASH have interesting properties related to the hepatic vasculature. Some other interesting drugs have been tested in animal models but further study in patients with NAFLD is warranted. In summary, in this paper we summarise the evidence that leads to the hypothesis that an increased intrahepatic vascular resistance and subsequent parenchymal hypoxia in early NAFLD is an important pathophysiological driving mechanism for the progression of the disease.
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