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McKay EJ, Luijten I, Weng X, Martinez de Morentin PB, De Frutos González E, Gao Z, Kolonin MG, Heisler LK, Semple RK. Mesenchymal-specific Alms1 knockout in mice recapitulates metabolic features of Alström syndrome. Mol Metab 2024; 84:101933. [PMID: 38583571 PMCID: PMC11047791 DOI: 10.1016/j.molmet.2024.101933] [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] [Received: 02/05/2024] [Accepted: 04/01/2024] [Indexed: 04/09/2024] Open
Abstract
OBJECTIVE Alström Syndrome (AS), caused by biallelic ALMS1 mutations, includes obesity with disproportionately severe insulin resistant diabetes, dyslipidemia, and fatty liver. Prior studies suggest that hyperphagia is accounted for by loss of ALMS1 function in hypothalamic neurones, whereas disproportionate metabolic complications may be due to impaired adipose tissue expandability. We tested this by comparing the metabolic effects of global and mesenchymal stem cell (MSC)-specific Alms1 knockout. METHODS Global Alms1 knockout (KO) mice were generated by crossing floxed Alms1 and CAG-Cre mice. A Pdgfrα-Cre driver was used to abrogate Alms1 function selectively in MSCs and their descendants, including preadipocytes. We combined metabolic phenotyping of global and Pdgfrα+ Alms1-KO mice on a 45% fat diet with measurements of body composition and food intake, and histological analysis of metabolic tissues. RESULTS Assessed on 45% fat diet to promote adipose expansion, global Alms1 KO caused hyperphagia, obesity, insulin resistance, dyslipidaemia, and fatty liver. Pdgfrα-cre driven KO of Alms1 (MSC KO) recapitulated insulin resistance, fatty liver, and dyslipidaemia in both sexes. Other phenotypes were sexually dimorphic: increased fat mass was only present in female Alms1 MSC KO mice. Hyperphagia was not evident in male Alms1 MSC KO mice, but was found in MSC KO females, despite no neuronal Pdgfrα expression. CONCLUSIONS Mesenchymal deletion of Alms1 recapitulates metabolic features of AS, including fatty liver. This confirms a key role for Alms1 in the adipose lineage, where its loss is sufficient to cause systemic metabolic effects and damage to remote organs. Hyperphagia in females may depend on Alms1 deficiency in oligodendrocyte precursor cells rather than neurones. AS should be regarded as a forme fruste of lipodystrophy.
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Affiliation(s)
- Eleanor J McKay
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Ineke Luijten
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Xiong Weng
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Pablo B Martinez de Morentin
- The Rowett Institute, University of Aberdeen, Aberdeen, UK; School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Elvira De Frutos González
- The Rowett Institute, University of Aberdeen, Aberdeen, UK; Área de Fisiología Humana, Departamento de Ciencias básicas de la Salud, Facultad de ciencias de la Salud, Universidad Rey Juan Carlos, 28922 Alcorcón, Madrid, Spain
| | - Zhanguo Gao
- Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston, Houston, TX 77030, USA
| | - Mikhail G Kolonin
- Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston, Houston, TX 77030, USA
| | - Lora K Heisler
- The Rowett Institute, University of Aberdeen, Aberdeen, UK
| | - Robert K Semple
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK; MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK.
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McKay EJ, Luijten I, Weng X, Martinez de Morentin PB, De Frutos González E, Gao Z, Kolonin MG, Heisler LK, Semple RK. Mesenchymal-specific Alms1 knockout in mice recapitulates key metabolic features of Alström Syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.12.562074. [PMID: 37873427 PMCID: PMC10592792 DOI: 10.1101/2023.10.12.562074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Background Alström Syndrome (AS), a multi-system disease caused by mutations in the ALMS1 gene, includes obesity with disproportionately severe insulin resistant diabetes, dyslipidemia, and hepatosteatosis. How loss of ALMS1 causes this phenotype is poorly understood, but prior studies have circumstancially implicated impaired adipose tissue expandability. We set out to test this by comparing the metabolic effects of selective Alms1 knockout in mesenchymal cells including preadipocytes to those of global Alms1 knockout. Methods Global Alms1 knockout (KO) mice were generated by crossing floxed Alms1 and CAG-Cre mice. A Pdgfrα -Cre driver was used to abrogate Alms1 function selectively in mesenchymal stem cells (MSCs) and their descendants, including preadipocytes. We combined metabolic phenotyping of global and Pdgfrα + Alms1 -KO mice on a 45% fat diet with measurements of body composition and food intake, and histological analysis of metabolic tissues. Results Global Alms1 KO caused hyperphagia, obesity, insulin resistance, dyslipidaemia, and fatty liver. Pdgfrα - cre driven KO of Alms1 (MSC KO) recapitulated insulin resistance, fatty liver, and dyslipidaemia in both sexes. Other phenotypes were sexually dimorphic: increased fat mass was only present in female Alms1 MSC KO mice. Hyperphagia was not evident in male Alms1 MSC KO mice, but was found in MSC KO females, despite no neuronal Pdgfr α expression. Conclusions Mesenchymal deletion of Alms1 recapitulates the metabolic features of AS, including severe fatty liver. This confirms a key role for Alms1 in the adipose lineage, where its loss is sufficient to cause systemic metabolic effects and damage to remote organs. AS should be regarded as a forme fruste of lipodystrophy. Therapies should prioritise targeting positive energy balance.
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Flessa CM, Nasiri-Ansari N, Kyrou I, Leca BM, Lianou M, Chatzigeorgiou A, Kaltsas G, Kassi E, Randeva HS. Genetic and Diet-Induced Animal Models for Non-Alcoholic Fatty Liver Disease (NAFLD) Research. Int J Mol Sci 2022; 23:ijms232415791. [PMID: 36555433 PMCID: PMC9780957 DOI: 10.3390/ijms232415791] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/05/2022] [Accepted: 12/10/2022] [Indexed: 12/15/2022] Open
Abstract
A rapidly increasing incidence of non-alcoholic fatty liver disease (NAFLD) is noted worldwide due to the adoption of western-type lifestyles and eating habits. This makes the understanding of the molecular mechanisms that drive the pathogenesis of this chronic disease and the development of newly approved treatments of utmost necessity. Animal models are indispensable tools for achieving these ends. Although the ideal mouse model for human NAFLD does not exist yet, several models have arisen with the combination of dietary interventions, genetic manipulations and/or administration of chemical substances. Herein, we present the most common mouse models used in the research of NAFLD, either for the whole disease spectrum or for a particular disease stage (e.g., non-alcoholic steatohepatitis). We also discuss the advantages and disadvantages of each model, along with the challenges facing the researchers who aim to develop and use animal models for translational research in NAFLD. Based on these characteristics and the specific study aims/needs, researchers should select the most appropriate model with caution when translating results from animal to human.
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Affiliation(s)
- Christina-Maria Flessa
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
| | - Narjes Nasiri-Ansari
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Ioannis Kyrou
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- Research Institute for Health and Wellbeing, Coventry University, Coventry CV1 5FB, UK
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK
- Laboratory of Dietetics and Quality of Life, Department of Food Science and Human Nutrition, School of Food and Nutritional Sciences, Agricultural University of Athens, 11855 Athens, Greece
| | - Bianca M. Leca
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
| | - Maria Lianou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Antonios Chatzigeorgiou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Gregory Kaltsas
- Endocrine Unit, 1st Department of Propaedeutic Internal Medicine, Laiko Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Eva Kassi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
- Endocrine Unit, 1st Department of Propaedeutic Internal Medicine, Laiko Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece
- Correspondence: (E.K.); (H.S.R.)
| | - Harpal S. Randeva
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- Correspondence: (E.K.); (H.S.R.)
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Ferguson AL, Kok LF, Luong JK, Van Den Bergh M, Bell-Anderson KS, Fazakerley DJ, Byrne SN. Exposure to solar ultraviolet radiation limits diet-induced weight gain, increases liver triglycerides and prevents the early signs of cardiovascular disease in mice. Nutr Metab Cardiovasc Dis 2019; 29:633-638. [PMID: 30956026 DOI: 10.1016/j.numecd.2019.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/21/2019] [Accepted: 02/21/2019] [Indexed: 02/09/2023]
Abstract
BACKGROUND AND AIMS Sunlight exposure is associated with a number of health benefits including protecting us from autoimmunity, cardiovascular disease, obesity and diabetes. Animal studies have confirmed that ultraviolet (UV)-B radiation, independently of vitamin D, can limit diet-induced obesity, metabolic syndrome and atherosclerosis. The aim of this study is to investigate whether exposure to the UV radiation contained in sunlight impacts on these disease parameters. METHODS AND RESULTS We have trialled an intervention with solar UV in obese and atherosclerosis-prone mice. We have discovered that solar-simulated UV can significantly limit diet-induced obesity and reduce atheroma development in mice fed a diet high in sugar and fat. The optimal regime for this benefit was exposure once a week to solar UV equivalent to approximately 30 min of summer sun. Exposure to this optimal dose of solar UV also led to a significant increase in liver triglycerides which may protect the liver from damage. CONCLUSION Our results show that the UV contained in sunlight has the potential to prevent and treat chronic disease at sites distant from irradiated skin. A major health challenge going forward will be to harness the power of the sun safely, without risking an increase in skin cancers.
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Affiliation(s)
- A L Ferguson
- The University of Sydney, Discipline of Infectious Diseases and Immunology, Central Clinical School, Faculty of Medicine and Health, Sydney, New South Wales, Australia; The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia; The Centenary Institute, Camperdown, New South Wales, Australia
| | - L F Kok
- The University of Sydney, Discipline of Infectious Diseases and Immunology, Central Clinical School, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - J K Luong
- The University of Sydney, Discipline of Infectious Diseases and Immunology, Central Clinical School, Faculty of Medicine and Health, Sydney, New South Wales, Australia; The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia
| | - M Van Den Bergh
- The University of Sydney, Discipline of Infectious Diseases and Immunology, Central Clinical School, Faculty of Medicine and Health, Sydney, New South Wales, Australia; The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia
| | - K S Bell-Anderson
- The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia; The University of Sydney, School of Life and Environmental Sciences, Faculty of Science, Sydney, New South Wales, Australia
| | - D J Fazakerley
- The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia; The University of Sydney, School of Life and Environmental Sciences, Faculty of Science, Sydney, New South Wales, Australia
| | - S N Byrne
- The University of Sydney, Discipline of Infectious Diseases and Immunology, Central Clinical School, Faculty of Medicine and Health, Sydney, New South Wales, Australia; The University of Sydney, Charles Perkins Centre, Sydney, New South Wales, Australia; Westmead Institute for Medical Research, Centre for Immunology and Allergy Research, Westmead, New South Wales, Australia.
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Bertola A. WITHDRAWN: Rodent models of fatty liver diseases. LIVER RESEARCH 2018. [DOI: 10.1016/j.livres.2018.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Santhekadur PK, Kumar DP, Sanyal AJ. Preclinical models of non-alcoholic fatty liver disease. J Hepatol 2018; 68:230-237. [PMID: 29128391 PMCID: PMC5775040 DOI: 10.1016/j.jhep.2017.10.031] [Citation(s) in RCA: 241] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 10/29/2017] [Accepted: 10/31/2017] [Indexed: 02/08/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) can manifest as non-alcoholic fatty liver (NAFL) or non-alcoholic steatohepatitis (NASH). NASH is often associated with progressive fibrosis which can lead to cirrhosis and hepatocellular carcinoma (HCC). NASH is increasing as an aetiology for end-stage liver disease as well as HCC. There are currently no approved therapies for NASH. A major barrier to development of therapeutics for NASH is the lack of preclinical models of disease that are appropriately validated to represent the biology and outcomes of human disease. Many in vitro and animal models have been developed. In vitro models do not fully capture the hepatic and extrahepatic milieu of human NASH and large animal models are expensive and logistically difficult to use. Therefore, there is considerable interest in the development and validation of mouse models for NAFLD, including NASH. Several models based on varying genetic or dietary manipulations have been developed. However, the majority do not recreate steatohepatitis, strictly defined as the presence of hepatocellular ballooning with or without Mallory-Denk bodies, accompanied by inflammation in the presence of macrovesicular steatosis. Others lack validation against human disease. Herein, we describe the best practices in development of mouse models of NASH. We further review existing models and the literature supporting their use as a surrogate for human disease. Finally, data on models to evaluate protective genes are discussed. It is hoped that this review will provide guidance for the interpretation of data derived from mouse models and also for the development and validation of newer models.
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Lau JKC, Zhang X, Yu J. Animal Models of Non-alcoholic Fatty Liver Diseases and Its Associated Liver Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1061:139-147. [DOI: 10.1007/978-981-10-8684-7_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Chen LH, Chien YW, Liang CT, Chan CH, Fan MH, Huang HY. Green tea extract induces genes related to browning of white adipose tissue and limits weight-gain in high energy diet-fed rat. Food Nutr Res 2017; 61:1347480. [PMID: 28804438 PMCID: PMC5533130 DOI: 10.1080/16546628.2017.1347480] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022] Open
Abstract
Background: A wealth of research has reported on the anti-obesity effects of green tea extract (GTE). Although browning of white adipose tissue (WAT) has been reported to attenuate obesity, no study has disclosed the effects of GTE on browning in Sprague Dawley rats. Objectives: The aims of the study were to investigate the effects of GTE on anti-obesity and browning, and their underlying mechanisms. Methods: Four groups of rats (n=10/group) were used including a normal diet with vehicle treatment, and a high-energy diet (HED) with vehicle or GTE by oral gavage at 77.5 or 155 mg/kg/day for 8 weeks. Body weight, fat accumulation, and serum biochemical parameters were used to evaluate obesity. The gene expressions were analyzed using RT-qPCR and western blotting. Results: GTE modulated HED-induced body weight, fat accumulation, and serum levels of triacylglycerol, total cholesterol, low-density lipoprotein, free fatty acids, aspartate aminotransferase, and alanine aminotransferase. Moreover, GTE enhanced the serum high-density lipoprotein. Most importantly, the biomarkers of beige adipose tissue were up-regulated in WAT in GTE-given groups. GTE induced genes involved in different pathways of browning, and reduced transducin-like enhancer protein-3 in WAT. Conclusion: Our results suggest that GTE may improve obesity through inducing browning in HED-fed rats. Abbreviations: ALT: Alanine transaminase; AST: Aspartate transaminase; BAT: Brown adipose tissue; BMP-7: Bone morphogenetic protein-7; BW: Body weight; CIDEA: Cell death activator; CPT-1: Carnitine palmitoyltransferase-1; EFP: Epididymal fat pad; FFA: Free fatty acid; FGF-21: Fibroblast growth factor-21; GTE: Green tea extract; HDL: High-density lipoprotein; HED: high-energy diet; LDL: Low-density lipoprotein; MFP: Mesenteric fat pad; PGC-1α: Activates PPAR-γ coactivator-1; PPAR-γ: Peroxisome proliferator-activated receptor-γ; PRDM-16: PR domain containing 16; RFP: Renal fat pad; SD: Sprague Dawley; TC: Total cholesterol; TG: Triacylglycerol; TLE-3: Transducin-like enhancer protein-3: UCP-1: Uncoupling protein-1; WAT: White adipose tissue.
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Affiliation(s)
- Li-Han Chen
- YongLin Biomedical Engineering Center, National Taiwan University, Taipei City, Taiwan
| | - Yi-Wen Chien
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei City, Taiwan
| | | | - Ching-Hung Chan
- Department of Food Science, Nutrition, and Nutraceutical Biotechnology, Shih Chien University, Taipei City, Taiwan
| | - Meng-Han Fan
- Department of Food Science, Nutrition, and Nutraceutical Biotechnology, Shih Chien University, Taipei City, Taiwan
| | - Hui-Yu Huang
- Department of Food Science, Nutrition, and Nutraceutical Biotechnology, Shih Chien University, Taipei City, Taiwan
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Hansen HH, Feigh M, Veidal SS, Rigbolt KT, Vrang N, Fosgerau K. Mouse models of nonalcoholic steatohepatitis in preclinical drug development. Drug Discov Today 2017; 22:1707-1718. [PMID: 28687459 DOI: 10.1016/j.drudis.2017.06.007] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/06/2017] [Accepted: 06/27/2017] [Indexed: 02/07/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in the Western world. NAFLD is a complex spectrum of liver diseases ranging from benign hepatic steatosis to its more aggressive necroinflammatory manifestation, nonalcoholic steatohepatitis (NASH). NASH pathogenesis is multifactorial and risk factors are almost identical to those of the metabolic syndrome. This has prompted substantial efforts to identify novel drug therapies for correcting underlying metabolic deficits, and to prevent or alleviate hepatic fibrosis in NASH. Available mouse models of NASH address different aspects of the disease, have varying clinical translatability, and, therefore, also show different utility in drug discovery.
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Affiliation(s)
- Henrik H Hansen
- Gubra Aps, Hørsholm Kongevej 11b, Hørsholm DK-2970, Denmark.
| | - Michael Feigh
- Gubra Aps, Hørsholm Kongevej 11b, Hørsholm DK-2970, Denmark
| | - Sanne S Veidal
- Gubra Aps, Hørsholm Kongevej 11b, Hørsholm DK-2970, Denmark
| | | | - Niels Vrang
- Gubra Aps, Hørsholm Kongevej 11b, Hørsholm DK-2970, Denmark
| | - Keld Fosgerau
- Gubra Aps, Hørsholm Kongevej 11b, Hørsholm DK-2970, Denmark
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Lau JKC, Zhang X, Yu J. Animal models of non-alcoholic fatty liver disease: current perspectives and recent advances. J Pathol 2016; 241:36-44. [PMID: 27757953 PMCID: PMC5215469 DOI: 10.1002/path.4829] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/12/2016] [Accepted: 10/13/2016] [Indexed: 12/12/2022]
Abstract
Non‐alcoholic fatty liver disease (NAFLD) is a continuous spectrum of diseases characterized by excessive lipid accumulation in hepatocytes. NAFLD progresses from simple liver steatosis to non‐alcoholic steatohepatitis and, in more severe cases, to liver fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Because of its growing worldwide prevalence, various animal models that mirror both the histopathology and the pathophysiology of each stage of human NAFLD have been developed. The selection of appropriate animal models continues to be one of the key questions faced in this field. This review presents a critical analysis of the histopathology and pathogenesis of NAFLD, the most frequently used and recently developed animal models for each stage of NAFLD and NAFLD‐induced HCC, the main mechanisms involved in the experimental pathogenesis of NAFLD in different animal models, and a brief summary of recent therapeutic targets found by the use of animal models. Integrating the data from human disease with those from animal studies indicates that, although current animal models provide critical guidance in understanding specific stages of NAFLD pathogenesis and progression, further research is necessary to develop more accurate models that better mimic the disease spectrum, in order to provide both increased mechanistic understanding and identification/testing of novel therapeutic approaches. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Jennie Ka Ching Lau
- Institute of Digestive Disease and the Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, PR China.,Faculty of Medicine, SHHO College, The Chinese University of Hong Kong, Hong Kong, PR China
| | - Xiang Zhang
- Institute of Digestive Disease and the Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, PR China
| | - Jun Yu
- Institute of Digestive Disease and the Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, PR China
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Pro-inflammatory obesity in aged cannabinoid-2 receptor-deficient mice. Int J Obes (Lond) 2015; 40:366-79. [PMID: 26303348 DOI: 10.1038/ijo.2015.169] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 07/19/2015] [Accepted: 08/13/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVES Cannabinoid-1 receptor signaling increases the rewarding effects of food intake and promotes the growth of adipocytes, whereas cannabinoid-2 receptor (CB2) possibly opposes these pro-obesity effects by silencing the activated immune cells that are key drivers of the metabolic syndrome. Pro- and anti-orexigenic cannabimimetic signaling may become unbalanced with age because of alterations of the immune and endocannabinoid system. METHODS To specifically address the role of CB2 for age-associated obesity, we analyzed metabolic, cardiovascular, immune and neuronal functions in 1.2-1.8-year-old CB2(-/-) and control mice, fed with a standard diet and assessed effects of the CB2 agonist, HU308, during high-fat diet (HFD) in 12-16-week-old mice. RESULTS The CB2(-/-) mice were obese with hypertrophy of visceral fat, immune cell polarization toward pro-inflammatory subpopulations in fat and liver and hypertension, as well as increased mortality despite normal blood glucose. They also developed stronger paw inflammation and a premature loss of transient receptor potential responsiveness in primary sensory neurons, a phenomenon typical for small fiber disease. The CB2 agonist HU308 prevented HFD-evoked hypertension, reduced HFD-evoked polarization of adipose tissue macrophages toward the M1-like pro-inflammatory type and reduced HFD-evoked nociceptive hypersensitivity, but had no effect on weight gain. CONCLUSIONS CB2 agonists may fortify CB2-mediated anti-obesity signaling without the risk of anti-CB1-mediated depression that caused the failure of rimonabant.
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Farrell GC, Mridha AR, Yeh MM, Arsov T, Van Rooyen DM, Brooling J, Nguyen T, Heydet D, Delghingaro-Augusto V, Nolan CJ, Shackel NA, McLennan SV, Teoh NC, Larter CZ. Strain dependence of diet-induced NASH and liver fibrosis in obese mice is linked to diabetes and inflammatory phenotype. Liver Int 2014; 34:1084-93. [PMID: 24107103 DOI: 10.1111/liv.12335] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 09/06/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Obese Alms1 mutant (foz/foz) NOD.B10 mice develop diabetes and fibrotic NASH when fed high-fat(HF) diet. To establish whether diabetes or obesity is more closely associated with NASH fibrosis, we compared diabetic foz/foz C57BL6/J with non-diabetic foz/foz BALB/c mice. We also determined hepatic cytokines, growth factors and related profibrotic pathways. METHODS Male and female foz/foz BALB/c and C57BL6/J mice were fed HF or chow for 24 weeks before determining metabolic indices, liver injury, cytokines, growth factors, pathology/fibrosis and matrix deposition pathways. RESULTS All foz/foz mice were obese. Hepatomegaly, hyperinsulinemia, hyperglycaemia and hypoadiponectinaemia occurred only in foz/foz C57BL6/J mice, whereas foz/foz BALB/c formed more adipose. Serum ALT, steatosis, ballooning, liver inflammation and NAFLD activity score were worse in C57BL6/J mice. In HF-fed mice, fibrosis was severe in foz/foz C57BL6/J, appreciable in WT C57BL6/J, but absent in foz/foz BALB/c mice. Hepatic mRNA expression of TNF-α, IL-12, IL-4, IL-10 was increased (but not IFN-γ, IL-1β, IL-17A), and IL-4:IFN-γ ratio (indicating Th-2 predominance) was higher in HF-fed foz/foz C57BL6/J than BALB/c mice. In livers of HF-fed foz/foz C57BL6/J mice, TGF-β was unaltered but PDGFα and CTGF were increased in association with enhanced α-SMA, CD147and MMP activity. CONCLUSIONS In mice with equivalent genetic/dietary obesity, NASH development is linked to strain differences in hyperinsulinaemia and hyperglycaemia inversely related to lipid partitioning between adipose and liver. Diabetes-mediated CTGF-regulation of MMPs as well as cytokines/growth factors (Th-2 cytokine predominant, PDGFα, not TGF-β) mobilized in the resultant hepatic necroinflammatory change may contribute to strain differences in NASH fibrosis.
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Affiliation(s)
- Geoffrey C Farrell
- Liver Research Group, Australian National University Medical School at The Canberra Hospital, Garran, ACT, Australia
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Tam J, Godlewski G, Earley BJ, Zhou L, Jourdan T, Szanda G, Cinar R, Kunos G. Role of adiponectin in the metabolic effects of cannabinoid type 1 receptor blockade in mice with diet-induced obesity. Am J Physiol Endocrinol Metab 2014; 306:E457-68. [PMID: 24381003 PMCID: PMC3923090 DOI: 10.1152/ajpendo.00489.2013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The adipocyte-derived hormone adiponectin promotes fatty acid oxidation and improves insulin sensitivity and thus plays a key role in the regulation of lipid and glucose metabolism and energy homeostasis. Chronic cannabinoid type 1 (CB1) receptor blockade also increases lipid oxidation and improves insulin sensitivity in obese individuals or animals, resulting in reduced cardiometabolic risk. Chronic CB1 blockade reverses the obesity-related decline in serum adiponectin levels, which has been proposed to account for the metabolic effects of CB1 antagonists. Here, we investigated the metabolic actions of the CB1 inverse agonist rimonabant in high-fat diet (HFD)-induced obese adiponectin knockout (Adipo(-/-)) mice and their wild-type littermate controls (Adipo(+/+)). HFD-induced obesity and its hormonal/metabolic consequences were indistinguishable in the two strains. Daily treatment of obese mice with rimonabant for 7 days resulted in significant and comparable reductions in body weight, serum leptin, free fatty acid, cholesterol, and triglyceride levels in the two strains. Rimonabant treatment improved glucose homeostasis and insulin sensitivity to the same extent in Adipo(+/+) and Adipo(-/-) mice, whereas it reversed the HFD-induced hepatic steatosis, fibrosis, and hepatocellular damage only in the former. The adiponectin-dependent, antisteatotic effect of rimonabant was mediated by reduced uptake and increased β-oxidation of fatty acids in the liver. We conclude that reversal of the HFD-induced hepatic steatosis and fibrosis by chronic CB1 blockade, but not the parallel reduction in adiposity and improved glycemic control, is mediated by adiponectin.
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Affiliation(s)
- Joseph Tam
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
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Bell-Anderson KS, Funnell AP, Williams H, Mat Jusoh H, Scully T, Lim WF, Burdach JG, Mak KS, Knights AJ, Hoy AJ, Nicholas HR, Sainsbury A, Turner N, Pearson RC, Crossley M. Loss of Krüppel-like factor 3 (KLF3/BKLF) leads to upregulation of the insulin-sensitizing factor adipolin (FAM132A/CTRP12/C1qdc2). Diabetes 2013; 62:2728-37. [PMID: 23633521 PMCID: PMC3717849 DOI: 10.2337/db12-1745] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Krüppel-like factor 3 (KLF3) is a transcriptional regulator that we have shown to be involved in the regulation of adipogenesis in vitro. Here, we report that KLF3-null mice are lean and protected from diet-induced obesity and glucose intolerance. On a chow diet, plasma levels of leptin are decreased, and adiponectin is increased. Despite significant reductions in body weight and adiposity, wild-type and knockout animals show equivalent energy intake, expenditure, and excretion. To investigate the molecular events underlying these observations, we used microarray analysis to compare gene expression in Klf3(+/+) and Klf3(-/-) tissues. We found that mRNA expression of Fam132a, which encodes a newly identified insulin-sensitizing adipokine, adipolin, is significantly upregulated in the absence of KLF3. We confirmed that KLF3 binds the Fam132a promoter in vitro and in vivo and that this leads to repression of promoter activity. Further, plasma adipolin levels were significantly increased in Klf3(-/-) mice compared with wild-type littermates. Boosting levels of adipolin via targeting of KLF3 offers a novel potential therapeutic strategy for the treatment of insulin resistance.
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Affiliation(s)
- Kim S Bell-Anderson
- School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, Australia.
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16
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Abstract
Metabolic disturbances are more prevalent in patients with schizophrenia (SCZ) than in the general population. The endocannabinoid system plays an important role in the regulation of dopamine transmission and several metabolic pathways, and the endocannabinoid receptor type 1 gene (CNR1) is considered a candidate gene for both SCZ and metabolic disorders. We examined whether genetic variation in CNR1 was associated with metabolic syndrome (MetS) in a naturalistic cohort of 407 patients with SCZ. The minor alleles of rs6928499, rs1535255, and rs2023239 were nominally associated with a lower risk of MetS [odds ratio (OR), 0.56; 95% confidence interval (CI), 0.37-0.84; P = 0.006; OR, 0.56; 95% CI, 0.37-0.84; P = 0.006; and OR, 0.44; 95% CI, 0.27-0.72; P = 0.001, respectively, adjusted for age, sex, duration of illness, clozapine or olanzapine treatment). These differences were mainly due to differences in high-density lipoprotein cholesterol and fasting glucose but not in body mass index or waist circumference. No significant association of the other polymorphisms (rs806377, rs1049353, rs6454674, and rs806379) with MetS was found. These results provide evidence that the prevalence of MetS is associated with the CNR1 gene in patients with SCZ during long-term treatment with antipsychotic treatment. Further studies are needed to uncover the exact molecular basis for this association, which could provide novel treatment targets for the MetS.
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Lipina C, Rastedt W, Irving AJ, Hundal HS. New vistas for treatment of obesity and diabetes? Endocannabinoid signalling and metabolism in the modulation of energy balance. Bioessays 2012; 34:681-91. [PMID: 22674489 DOI: 10.1002/bies.201200031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Growing evidence suggests that pathological overactivation of the endocannabinoid system (ECS) is associated with dyslipidemia, obesity and diabetes. Indeed, this signalling system acting through cannabinoid receptors has been shown to function both centrally and peripherally to regulate feeding behaviour as well as energy expenditure and metabolism. Consequently, modulation of these receptors can promote significant alterations in body weight and associated metabolic profile. Importantly, blocking cannabinoid receptor type 1 function has been found to prevent obesity and metabolic dysfunction in various murine models and in humans. Here we provide a detailed account of the known physiological role of the ECS in energy balance, and explore how recent studies have delivered novel insights into the potential targeting of this system as a therapeutic means for treating obesity and related metabolic disorders.
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Affiliation(s)
- Christopher Lipina
- Division of Cell Signalling and Immunology, Sir James Black Centre, College of Life Sciences, University of Dundee, Dundee, Scotland
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