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Kineman RD, Del Rio-Moreno M, Waxman DJ. Liver-specific actions of GH and IGF1 that protect against MASLD. Nat Rev Endocrinol 2024:10.1038/s41574-024-01037-0. [PMID: 39322791 DOI: 10.1038/s41574-024-01037-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/29/2024] [Indexed: 09/27/2024]
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD; also known as nonalcoholic fatty liver disease) is a chronic condition associated with metabolic syndrome, a group of conditions that includes obesity, insulin resistance, hyperlipidaemia and cardiovascular disease. Primary growth hormone (GH) deficiency is associated with MASLD, and the decline in circulating levels of GH with weight gain might contribute to the development of MASLD. Raising endogenous GH secretion or administering GH replacement therapy in the context of MASLD enhances insulin-like growth factor 1 (IGF1) production and reduces steatosis and the severity of liver injury. GH and IGF1 indirectly control MASLD progression by regulating systemic metabolic function. Evidence supports the proposal that GH and IGF1 also have a direct role in regulating liver metabolism and health. This Review focuses on how GH acts on the hepatocyte in a sex-dependent manner to limit lipid accumulation, reduce stress, and promote survival and regeneration. In addition, we discuss how GH and IGF1 might regulate non-parenchymal cells of the liver to control inflammation and fibrosis, which have a major effect on hepatocyte survival and regeneration. Development of a better understanding of how GH and IGF1 coordinate the functions of specific, individual liver cell types might provide insight into the aetiology of MASLD initiation and progression and suggest novel approaches for the treatment of MASLD.
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Affiliation(s)
- Rhonda D Kineman
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL, USA.
- Jesse Brown VA Medical Center, Research and Development Division, Chicago, IL, USA.
| | - Mercedes Del Rio-Moreno
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL, USA
- Jesse Brown VA Medical Center, Research and Development Division, Chicago, IL, USA
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA, USA
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2
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Yang M, Zhao W, Wang Z, Liu J, Sun X, Wang S. Detection of key gene InDels in JAK/STAT pathway and their associations with growth traits in four Chinese sheep breeds. Gene 2023; 888:147750. [PMID: 37657690 DOI: 10.1016/j.gene.2023.147750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/11/2023] [Accepted: 08/29/2023] [Indexed: 09/03/2023]
Abstract
OBJECTIVE The Janus kinase/signal transducer and transporter activator (JAK/STAT) signaling pathway plays crucial roles in lipid metabolism, glucose metabolism and cell senescence, suggesting that they are potential candidate genes affecting growth traits in animals. The present study aimed to evaluate the association between InDels in the JAK/STAT pathway and growth traits of four Chinese sheep breeds, including Tong sheep, Hu sheep, Small-tailed Han sheep and Lanzhou fat-tailed sheep. RESULTS Seventy-six indel loci of 11 genes in JAK/STAT were detected, and three genotypes were selected at four loci by PCR amplification, electrophoresis and sequencing, including one locus in STAT3, one locus in STAT5A, and two loci in JAK1. The Correlation analysis indicated that there was no significant correlation between STAT3 and growth traits in four sheep breeds (P > 0.05); STAT5A was significantly associated with body height, rump width and tube circumference in Hu sheep and body length in Tong sheep (P < 0.05); JAK1 was significantly correlated with body height, body oblique length, cross height and tube circumference in Hu sheep (P < 0.05) and body oblique length, cross height and tube circumference in small-tailed Han sheep (P < 0.05). CONCLUSION Overall, our results indicated a potential association between the growth traits of sheep and the InDels of JAK1 and STAT5A.
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Affiliation(s)
- Mengzhe Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Wanxia Zhao
- College of Grassland Agriculture, Northwest A&F University, Yangling, China
| | - Ziteng Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Junhai Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Xiuzhu Sun
- College of Grassland Agriculture, Northwest A&F University, Yangling, China
| | - Shuhui Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, China.
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Harvey I, Richard AJ, Mendoza TM, Stephens JM. Adipocyte STAT5 (signal transducer and activator of transcription 5) is not required for glucocorticoid-induced metabolic dysfunction. Am J Physiol Endocrinol Metab 2023; 325:E438-E447. [PMID: 37702737 PMCID: PMC10864007 DOI: 10.1152/ajpendo.00116.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/16/2023] [Accepted: 09/06/2023] [Indexed: 09/14/2023]
Abstract
Excess glucocorticoid (GC) signaling in adipose tissue is a key driver of insulin resistance and hepatic steatosis, but underlying mechanisms have not been fully elucidated. Signal transducer and activator of transcription 5 (STAT5) signaling in adipocytes has also been implicated in the progression of similar metabolic disturbances. Although STAT5 has been shown to interact with the glucocorticoid receptor (GR) in many cell types including adipocytes, the relevance of the STAT5/GR complex has not been investigated in adipocytes. Adult male and female adipocyte-specific STAT5 knockout (STAT5AKO) and floxed mice were given corticosterone (CORT) or vehicle in their drinking water for 1 wk and examined for differences in their metabolic responses to GC excess. CORT-induced lipolysis, insulin resistance, and changes in body composition were comparable between genotypes and in both sexes. Adipocyte STAT5 is not necessary for GC-mediated progression of metabolic disease.NEW & NOTEWORTHY Both STAT5 and glucocorticoid receptor contribute to metabolic processes and type 2 diabetes, in large part, due to their functions in adipocytes. These two transcription factors can form a complex and function together. Our novel studies determined the role of adipocyte STAT5 in glucocorticoid-induced diabetes. We observed that STAT5 in adipocytes is not needed for glucocorticoid-induced diabetes.
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Affiliation(s)
- Innocence Harvey
- Adipocyte Biology Department, Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States
| | - Allison J Richard
- Adipocyte Biology Department, Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States
| | - Tamra M Mendoza
- Adipocyte Biology Department, Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States
| | - Jacqueline M Stephens
- Adipocyte Biology Department, Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States
- Biological Sciences Department, Louisiana State University, Baton Rouge, Louisiana, United States
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Chang G, Li Y, Jiang Y, Wang C, Liu X. Mediation effect of JAK2 methylation on the association between sitting time and abdominal obesity in rural adults. Eur J Clin Nutr 2023; 77:1093-1099. [PMID: 37582927 DOI: 10.1038/s41430-023-01316-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 07/14/2023] [Accepted: 07/19/2023] [Indexed: 08/17/2023]
Abstract
BACKGROUND Sitting time may affect health by altering the methylation of certain genes. This research aimed to estimate the association of sitting time with abdominal obesity and the role of Janus kinase 2 (JAK2) methylation in the association among rural adults. METHODS A total of 1062 rural adults from the Henan Rural Cohort Study were included. Whole blood was used to extract genomic DNA. JAK2 DNA methylation level was assessed by MethylTargetTM. The logistic regression model was utilized to assess the association of sitting time with abdominal obesity, and the possible effect of JAK2 DNA methylation on the association were conducted by using mediation analyses. RESULTS Average time of sitting of participants was 7.28 ± 3.37 h/d. For per 1 h increment in sitting time, the odd ratio (OR) and 95% confidence interval (CI) of abdominal obesity was 1.153 (1.095, 1.214) after controlling potential risk factors. Simultaneously, the methylation levels of Chr9: 4985407 site and Chr9: 4985238-4985455 region were negatively correlated with abdominal obesity (OR: 0.549, 95% CI: 0.394, 0.765; OR: 0.189, 95% CI: 0.056, 0.640, respectively). Moreover, Chr9: 4985407 site and Chr9: 4985238-4985455 region methylation levels mediated the association of sitting time with abdominal obesity, and the indirect effects account for 6.78% and 4.24%, respectively. CONCLUSIONS Longer sitting time was positively correlated with abdominal obesity in the rural population, and methylation level of JAK2 may be an underlying mediation of the effect.
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Affiliation(s)
- Gaohua Chang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Yuqian Li
- Department of Clinical Pharmacology, School of Pharmaceutical Science, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Yujie Jiang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Chongjian Wang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xiaotian Liu
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, 450001, Henan, China.
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Ma IL, Stanley TL. Growth hormone and nonalcoholic fatty liver disease. IMMUNOMETABOLISM (COBHAM, SURREY) 2023; 5:e00030. [PMID: 37520312 PMCID: PMC10373851 DOI: 10.1097/in9.0000000000000030] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 07/06/2023] [Indexed: 08/01/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a prevalent cause of liver disease and metabolic comorbidities. Obesity is strongly associated with NAFLD and is also a state of relative deficiency of growth hormone (GH). Evidence supports a role of reduced GH and insulin-like growth factor-1 (IGF-1) in NAFLD pathogenesis. Physiological actions of GH in the liver include suppression of de novo lipogenesis (DNL) and promotion of lipid beta-oxidation, and GH also appears to have anti-inflammatory actions. Physiologic actions of IGF-1 include suppression of inflammatory and fibrogenic pathways important in the evolution from steatosis to steatohepatitis and fibrosis. Rodent models of impaired hepatic GH signaling show the development of steatosis, sometimes accompanied by inflammation, hepatocellular damage, and fibrosis, and these changes are ameliorated by treatment with GH and/or IGF-1. In humans, individuals with GH deficiency and GH resistance demonstrate an increased prevalence of NAFLD compared to controls, with improvement in hepatic lipid, steatohepatitis, and fibrosis following GH replacement. As a corollary, individuals with GH excess demonstrate lower hepatic lipid compared to controls along with increased hepatic lipid following treatment to normalize GH levels. Clinical trials demonstrate that augmentation of GH reduces hepatic lipid content in individuals with NAFLD and may also ameliorate steatohepatitis and fibrosis. Taken together, evidence supports an important role for perturbations in the GH/IGF-1 axis as one of the pathogenic mechanisms of NAFLD and suggests that further study is needed to assess whether augmentation of GH and/or IGF-1 may be a safe and effective therapeutic strategy for NAFLD.
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Affiliation(s)
- Ingrid L. Ma
- Metabolism Unit, Endocrine Division, Massachusetts General Hospital, Boston, MA, USA
| | - Takara L. Stanley
- Metabolism Unit, Endocrine Division, Massachusetts General Hospital, Boston, MA, USA
- Pediatric Endocrine Division, Massachusetts General Hospital, Boston, MA, USA
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6
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Li Q, Wang O, Ji B, Zhao L, Zhao L. Alcohol, White Adipose Tissue, and Brown Adipose Tissue: Mechanistic Links to Lipogenesis and Lipolysis. Nutrients 2023; 15:2953. [PMID: 37447280 PMCID: PMC10346806 DOI: 10.3390/nu15132953] [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: 05/14/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
According to data from the World Health Organization, there were about 3 million deaths caused by alcohol consumption worldwide in 2016, of which about 50% were related to liver disease. Alcohol consumption interfering with the normal function of adipocytes has an important impact on the pathogenesis of alcoholic liver disease. There has been increasing recognition of the crucial role of adipose tissue in regulating systemic metabolism, far beyond that of an inert energy storage organ in recent years. The endocrine function of adipose tissue is widely recognized, and the significance of the proteins it produces and releases is still being investigated. Alcohol consumption may affect white adipose tissue (WAT) and brown adipose tissue (BAT), which interact with surrounding tissues such as the liver and intestines. This review briefly introduces the basic concept and classification of adipose tissue and summarizes the mechanism of alcohol affecting lipolysis and lipogenesis in WAT and BAT. The adipose tissue-liver axis is crucial in maintaining lipid homeostasis within the body. Therefore, this review also demonstrates the effects of alcohol consumption on the adipose tissue-liver axis to explore the role of alcohol consumption in the crosstalk between adipose tissue and the liver.
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Affiliation(s)
- Qing Li
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, China;
| | - Ou Wang
- National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing 100050, China;
| | - Baoping Ji
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China;
| | - Liang Zhao
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, China;
| | - Lei Zhao
- School of Food and Health, Beijing Technology and Business University, Beijing 100048, China
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7
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Cao R, Tian H, Zhang Y, Liu G, Xu H, Rao G, Tian Y, Fu X. Signaling pathways and intervention for therapy of type 2 diabetes mellitus. MedComm (Beijing) 2023; 4:e283. [PMID: 37303813 PMCID: PMC10248034 DOI: 10.1002/mco2.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 06/13/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) represents one of the fastest growing epidemic metabolic disorders worldwide and is a strong contributor for a broad range of comorbidities, including vascular, visual, neurological, kidney, and liver diseases. Moreover, recent data suggest a mutual interplay between T2DM and Corona Virus Disease 2019 (COVID-19). T2DM is characterized by insulin resistance (IR) and pancreatic β cell dysfunction. Pioneering discoveries throughout the past few decades have established notable links between signaling pathways and T2DM pathogenesis and therapy. Importantly, a number of signaling pathways substantially control the advancement of core pathological changes in T2DM, including IR and β cell dysfunction, as well as additional pathogenic disturbances. Accordingly, an improved understanding of these signaling pathways sheds light on tractable targets and strategies for developing and repurposing critical therapies to treat T2DM and its complications. In this review, we provide a brief overview of the history of T2DM and signaling pathways, and offer a systematic update on the role and mechanism of key signaling pathways underlying the onset, development, and progression of T2DM. In this content, we also summarize current therapeutic drugs/agents associated with signaling pathways for the treatment of T2DM and its complications, and discuss some implications and directions to the future of this field.
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Affiliation(s)
- Rong Cao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Huimin Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yu Zhang
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Geng Liu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Haixia Xu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Guocheng Rao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yan Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Xianghui Fu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
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8
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Zhao L, Jiang H. Growth hormone stimulates lipolysis in mice but not in adipose tissue or adipocyte culture. Front Endocrinol (Lausanne) 2023; 13:1028191. [PMID: 36686475 PMCID: PMC9846043 DOI: 10.3389/fendo.2022.1028191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 12/14/2022] [Indexed: 01/06/2023] Open
Abstract
The inhibitory effect of growth hormone (GH) on adipose tissue growth and the stimulatory effect of GH on lipolysis are well known, but the mechanisms underlying these effects are not completely understood. In this study, we revisited the effects of GH on adipose tissue growth and lipolysis in the lit/lit mouse model. The lit/lit mice are GH deficient because of a mutation in the GH releasing hormone receptor gene. We found that the lit/lit mice had more subcutaneous fat and larger adipocytes than their heterozygous lit/+ littermates and that these differences were partially reversed by 4-week GH injection. We also found that GH injection to the lit/lit mice caused the mature adipose tissue and adipocytes to reduce in size. These results demonstrate that GH inhibits adipose tissue growth at least in part by stimulating lipolysis. To determine the mechanism by which GH stimulates lipolysis, we cultured adipose tissue explants and adipocytes derived from lit/lit mice with GH and/or isoproterenol, an agonist of the beta-adrenergic receptors. These experiments showed that whereas isoproterenol, expectedly, stimulated potent lipolysis, GH, surprisingly, had no effect on basal lipolysis or isoproterenol-induced lipolysis in adipose tissue explants or adipocytes. We also found that both isoproterenol-induced lipolysis and phosphorylation of hormone-sensitive lipase were not different between lit/lit and lit/+ mice. Taken together, these results support the conclusion that GH has lipolytic effect in mice but argue against the notion that GH stimulates lipolysis by directly acting on adipocytes or by enhancing β-adrenergic receptors-mediated lipolysis.
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Affiliation(s)
| | - Honglin Jiang
- School of Animal Sciences, Virginia Tech, Blacksburg, VA, United States
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Yepmo M, Potier JB, Pinget M, Grabarz A, Bouzakri K, Dumond Bourie A. Discussing the role of circular RNA in the pathogenesis of non-alcoholic fatty liver disease and its complications. Front Endocrinol (Lausanne) 2022; 13:1035159. [PMID: 36407314 PMCID: PMC9667057 DOI: 10.3389/fendo.2022.1035159] [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: 09/02/2022] [Accepted: 10/17/2022] [Indexed: 01/24/2023] Open
Abstract
Circular RNAs (circRNAs) are class of non-coding RNA, which are characterized by a covalently closed loop structure. Functionally they can act on cellular physiology, notably by sponging microRNAs (miR), regulating gene expression or interacting with binding protein. To date, circRNAs might represent an interesting, underexploited avenue for new target discovery for therapeutic applications, especially in the liver. The first characteristic of non-alcoholic fatty liver disease (NAFLD) is hepatic cholesterol accumulation, followed by its advanced form of the affection, nonalcoholic steatohepatitis (NASH), due to the occurrence of lobular inflammation, irreversible fibrosis, and in some cases hepatocellular carcinoma (HCC). Therefore, studies have investigated the importance of the dysregulation of circRNAs in the onset of metabolic disorders. In this review, we summarize the potential role of circRNAs in the development of metabolic diseases associated with the liver such as NAFLD or NASH, and their potential to become therapeutic strategies for these pathologies.
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Affiliation(s)
- Melissa Yepmo
- Centre européen d’étude du Diabète, Unité Mixte de Recherche de l’Université de Strasbourg « Diabète et Thérapeutique », Strasbourg, France
| | - Jean-Baptiste Potier
- Centre européen d’étude du Diabète, Unité Mixte de Recherche de l’Université de Strasbourg « Diabète et Thérapeutique », Strasbourg, France
- ILONOV, Strasbourg, France
| | - Michel Pinget
- Centre européen d’étude du Diabète, Unité Mixte de Recherche de l’Université de Strasbourg « Diabète et Thérapeutique », Strasbourg, France
| | | | - Karim Bouzakri
- Centre européen d’étude du Diabète, Unité Mixte de Recherche de l’Université de Strasbourg « Diabète et Thérapeutique », Strasbourg, France
- ILONOV, Strasbourg, France
| | - Aurore Dumond Bourie
- Centre européen d’étude du Diabète, Unité Mixte de Recherche de l’Université de Strasbourg « Diabète et Thérapeutique », Strasbourg, France
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Dichtel LE, Corey KE, Haines MS, Chicote ML, Kimball A, Colling C, Simon TG, Long MT, Husseini J, Bredella MA, Miller KK. The GH/IGF-1 Axis Is Associated With Intrahepatic Lipid Content and Hepatocellular Damage in Overweight/Obesity. J Clin Endocrinol Metab 2022; 107:e3624-e3632. [PMID: 35779256 PMCID: PMC9387707 DOI: 10.1210/clinem/dgac405] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Indexed: 01/25/2023]
Abstract
CONTEXT Obesity is a state of relative growth hormone (GH) deficiency, and GH has been identified as a candidate disease-modifying target in nonalcoholic fatty liver disease (NAFLD) because of its lipolytic and anti-inflammatory properties. However, the GH/IGF-1 axis has not been well characterized in NAFLD. OBJECTIVE We aimed to investigate serum GH and IGF-1 levels in relation to intrahepatic lipid content (IHL) and markers of hepatocellular damage and fibrosis in NAFLD. METHODS This cross-sectional study included 102 adults (43% women; age 19-67; BMI ≥ 25 kg/m2) without type 2 diabetes. IHL was measured by magnetic resonance spectroscopy; NAFLD was defined by ≥ 5% IHL. Peak-stimulated GH in response to GH releasing hormone and arginine was assessed as was serum IGF-1 (LC/MS). RESULTS There was no difference in mean age, BMI, or sex distribution in NAFLD vs controls. Mean (± SD) IHL was higher in NAFLD vs controls (21.8 ± 13.3% vs 2.9 ± 1.1%, P < 0.0001). Mean peak-stimulated GH was lower in NAFLD vs controls (9.0 ± 6.3 vs 15.4 ± 11.2 ng/mL, P = 0.003), including after controlling for age, sex, visceral adipose tissue, and fasting glucose. In a stepwise model, peak-stimulated GH predicted 14.6% of the variability in IHL (P = 0.004). Higher peak-stimulated GH was also associated with lower ALT. Higher serum IGF-1 levels were associated with lower risk of liver fibrosis by Fibrosis-4 scores. CONCLUSION Individuals with NAFLD have lower peak-stimulated GH levels but similar IGF-1 levels as compared to controls. Higher peak-stimulated GH levels are associated with lower IHL and less hepatocellular damage. Higher IGF-1 levels are associated with more favorable fibrosis risk scores. These data implicate GH and IGF-1 as potential disease modifiers in the development and progression of NAFLD.
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Affiliation(s)
- Laura E Dichtel
- Correspondence: Laura Dichtel, MD, Neuroendocrine Unit, Massachusetts General Hospital, 55 Fruit Street, BUL457, Boston, MA 02114, USA.
| | - Kathleen E Corey
- Division of Gastroenterology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Melanie S Haines
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Mark L Chicote
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Allison Kimball
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Caitlin Colling
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Tracey G Simon
- Division of Gastroenterology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Michelle T Long
- Section of Gastroenterology, Boston Medical Center, Boston University School of Medicine, Boston, MA, USA
| | - Jad Husseini
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA
| | - Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA
| | - Karen K Miller
- Neuroendocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
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11
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Osganian SA, Subudhi S, Masia R, Drescher HK, Bartsch LM, Chicote ML, Chung RT, Gee DW, Witkowski ER, Bredella MA, Lauer GM, Corey KE, Dichtel LE. Expression of IGF-1 receptor and GH receptor in hepatic tissue of patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Growth Horm IGF Res 2022; 65:101482. [PMID: 35780715 PMCID: PMC9885486 DOI: 10.1016/j.ghir.2022.101482] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 06/02/2022] [Accepted: 06/12/2022] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The GH and IGF-1 axis is a candidate disease-modifying target in nonalcoholic fatty liver disease (NAFLD) given its lipolytic, anti-inflammatory and anti-fibrotic properties. IGF-1 receptor (IGF-1R) and GH receptor (GHR) expression in adult, human hepatic tissue is not well understood across the spectrum of NAFLD severity. Therefore, we sought to investigate hepatic IGF-1R and GHR expression in subjects with NAFLD utilizing gene expression analysis (GEA) and immunohistochemistry (IHC). DESIGN GEA (n = 318) and IHC (n = 30) cohorts were identified from the Massachusetts General Hospital NAFLD Tissue Repository. GEA subjects were categorized based on histopathology as normal liver histology (NLH), steatosis only (Steatosis), nonalcoholic steatohepatitis (NASH) without fibrosis (NASH F0), and NASH with fibrosis (NASH F1-4) with GEA by the Nanostring nCounter assay. IHC subjects were matched for age, body mass index (BMI), sex, and diabetic status across three groups (n = 10 each): NLH, Steatosis, and NASH with fibrosis (NASH F1-3). IHC for IGF-1R, IGF-1 and GHR was performed on formalin-fixed, paraffin-embedded hepatic tissue samples. RESULTS IGF-1R gene expression did not differ across NAFLD severity while IGF-1 gene expression decreased with increasing NAFLD severity, including when controlled for BMI and age. GHR expression did not differ by severity of NAFLD based on GEA or IHC. CONCLUSIONS IGF-1R and GHR expression levels were not significantly different across NAFLD disease severity. However, expression of IGF-1 was lower with increasing severity of NAFLD. Additional research is needed regarding the contribution of the GH/IGF-1 axis to the pathophysiology of NAFLD and NASH.
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Affiliation(s)
- Stephanie A Osganian
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA
| | - Sonu Subudhi
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | - Ricard Masia
- Harvard Medical School (HMS), Boston, MA, USA; Department of Pathology, MGH, Boston, MA, USA
| | - Hannah K Drescher
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | - Lea M Bartsch
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | | | - Raymond T Chung
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | - Denise W Gee
- Harvard Medical School (HMS), Boston, MA, USA; Department of Surgery, MGH, Boston, MA, USA
| | - Elan R Witkowski
- Harvard Medical School (HMS), Boston, MA, USA; Department of Surgery, MGH, Boston, MA, USA
| | - Miriam A Bredella
- Harvard Medical School (HMS), Boston, MA, USA; Department of Radiology, Division of Musculoskeletal Radiology and Interventions, MGH, Boston, MA, USA
| | - Georg M Lauer
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | - Kathleen E Corey
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital (MGH), Boston, MA, USA; Harvard Medical School (HMS), Boston, MA, USA
| | - Laura E Dichtel
- Harvard Medical School (HMS), Boston, MA, USA; Neuroendocrine Unit, MGH, Boston, MA, USA.
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12
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Qian Y, Berryman DE, Basu R, List EO, Okada S, Young JA, Jensen EA, Bell SRC, Kulkarni P, Duran-Ortiz S, Mora-Criollo P, Mathes SC, Brittain AL, Buchman M, Davis E, Funk KR, Bogart J, Ibarra D, Mendez-Gibson I, Slyby J, Terry J, Kopchick JJ. Mice with gene alterations in the GH and IGF family. Pituitary 2022; 25:1-51. [PMID: 34797529 PMCID: PMC8603657 DOI: 10.1007/s11102-021-01191-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/21/2021] [Indexed: 01/04/2023]
Abstract
Much of our understanding of GH's action stems from animal models and the generation and characterization of genetically altered or modified mice. Manipulation of genes in the GH/IGF1 family in animals started in 1982 when the first GH transgenic mice were produced. Since then, multiple laboratories have altered mouse DNA to globally disrupt Gh, Ghr, and other genes upstream or downstream of GH or its receptor. The ability to stay current with the various genetically manipulated mouse lines within the realm of GH/IGF1 research has been daunting. As such, this review attempts to consolidate and summarize the literature related to the initial characterization of many of the known gene-manipulated mice relating to the actions of GH, PRL and IGF1. We have organized the mouse lines by modifications made to constituents of the GH/IGF1 family either upstream or downstream of GHR or to the GHR itself. Available data on the effect of altered gene expression on growth, GH/IGF1 levels, body composition, reproduction, diabetes, metabolism, cancer, and aging are summarized. For the ease of finding this information, key words are highlighted in bold throughout the main text for each mouse line and this information is summarized in Tables 1, 2, 3 and 4. Most importantly, the collective data derived from and reported for these mice have enhanced our understanding of GH action.
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Affiliation(s)
- Yanrong Qian
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Reetobrata Basu
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Edward O List
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Shigeru Okada
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Pediatrics, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Jonathan A Young
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Elizabeth A Jensen
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- Translational Biomedical Sciences Doctoral Program, Ohio University, Athens, OH, USA
| | - Stephen R C Bell
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Prateek Kulkarni
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | | | - Patricia Mora-Criollo
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Translational Biomedical Sciences Doctoral Program, Ohio University, Athens, OH, USA
| | - Samuel C Mathes
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Alison L Brittain
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Mat Buchman
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Emily Davis
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Kevin R Funk
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
| | - Jolie Bogart
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Diego Ibarra
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Chemistry and Biochemistry, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Isaac Mendez-Gibson
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- College of Health Sciences and Professions, Ohio University, Athens, OH, USA
| | - Julie Slyby
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Joseph Terry
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA.
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
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13
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Richard AJ, Hang H, Allerton TD, Zhao P, Mendoza T, Ghosh S, Elks CM, Stephens JM. Loss of Adipocyte STAT5 Confers Increased Depot-Specific Adiposity in Male and Female Mice That Is Not Associated With Altered Adipose Tissue Lipolysis. Front Endocrinol (Lausanne) 2022; 13:812802. [PMID: 35464049 PMCID: PMC9022209 DOI: 10.3389/fendo.2022.812802] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 02/24/2022] [Indexed: 01/05/2023] Open
Abstract
STATs (Signal Transducers and Activators of Transcription) 5A and 5B are induced during adipocyte differentiation and are primarily activated by growth hormone (GH) and prolactin in fat cells. Previous studies in mice lacking adipocyte GH receptor or STAT5 support their roles in lipolysis-mediated reduction of adipose tissue mass. Male and female mice harboring adipocyte-specific deletion of both STAT5 genes (STAT5AKO) exhibit increased subcutaneous or inguinal adipose tissue mass, but no changes in visceral or gonadal fat mass. Both depots display substantial increases in adipocyte size with no changes in lipolysis in adipose tissue explants. RNA sequencing analysis of subcutaneous adipose tissue and indirect calorimetry experiments reveal sex-dependent differences in adipose gene expression and whole-body energy expenditure, respectively, resulting from the loss of adipocyte STAT5.
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Affiliation(s)
- Allison J. Richard
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Hardy Hang
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Timothy D. Allerton
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Peng Zhao
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Tamra Mendoza
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Sujoy Ghosh
- Cardiovascular and Metabolic Disease Program and Center for Computational Biology, Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Carrie M. Elks
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Jacqueline M. Stephens
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, United States
- *Correspondence: Jacqueline M. Stephens,
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14
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Molecular and clinical effects of selective TYK2 inhibition with deucravacitinib in psoriasis. J Allergy Clin Immunol 2021; 149:2010-2020.e8. [PMID: 34767869 DOI: 10.1016/j.jaci.2021.11.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 09/20/2021] [Accepted: 11/01/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Psoriasis, a chronic inflammatory disease dependent on the interleukin (IL)-23/T helper cell 17 (Th17) pathway, is initiated through plasmacytoid dendritic cell activation and type I interferon induction in the skin. Deucravacitinib, a selective tyrosine kinase 2 (TYK2) inhibitor, blocks IL-23, IL-12, and type I interferon signaling in cellular assays. OBJECTIVE Investigate changes in IL-23/Th17- and type I interferon-pathway biomarkers and gene responses, and measures of selectivity for TYK2 over Janus kinases (JAKs) 1-3, in patients with moderate to severe psoriasis receiving deucravacitinib. METHODS Deucravacitinib was evaluated in a randomized, placebo-controlled, dose-ranging trial. Biopsies from non-lesional (Day 1) and lesional skin (Days 1, 15, and 85) were assessed for changes in IL-23/IL-12 and type I interferon pathway biomarkers by quantitative reverse-transcription polymerase chain reaction, RNA sequencing, and immunohistochemistry. Laboratory markers were measured in blood. Percent change from baseline in Psoriasis Area and Severity Index (PASI) score was assessed. RESULTS IL-23 pathway biomarkers in lesional skin returned toward non-lesional levels dose-dependently with deucravacitinib. Interferon and IL-12 pathway genes were normalized. Markers of keratinocyte dysregulation, keratin-16, and β-defensin genes approached non-lesional levels with effective dosages. Select laboratory parameters impacted by JAK1-3 inhibition were unaffected by deucravacitinib. Greater improvements in PASI scores, correlated with biomarker changes, were seen with the highest dosages of deucravacitinib versus lower dosages or placebo. CONCLUSION Robust clinical efficacy with deucravacitinib treatment was associated with decreases in IL-23/Th17 and interferon pathway biomarkers. The lack of effect seen on biomarkers specific to JAK1-3 inhibition support selectivity of deucravacitinib for TYK2; larger studies are needed to further confirm.
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15
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Towards Understanding the Direct and Indirect Actions of Growth Hormone in Controlling Hepatocyte Carbohydrate and Lipid Metabolism. Cells 2021; 10:cells10102532. [PMID: 34685512 PMCID: PMC8533955 DOI: 10.3390/cells10102532] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 02/06/2023] Open
Abstract
Growth hormone (GH) is critical for achieving normal structural growth. In addition, GH plays an important role in regulating metabolic function. GH acts through its GH receptor (GHR) to modulate the production and function of insulin-like growth factor 1 (IGF1) and insulin. GH, IGF1, and insulin act on multiple tissues to coordinate metabolic control in a context-specific manner. This review will specifically focus on our current understanding of the direct and indirect actions of GH to control liver (hepatocyte) carbohydrate and lipid metabolism in the context of normal fasting (sleep) and feeding (wake) cycles and in response to prolonged nutrient deprivation and excess. Caveats and challenges related to the model systems used and areas that require further investigation towards a clearer understanding of the role GH plays in metabolic health and disease are discussed.
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16
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Sarmento-Cabral A, del Rio-Moreno M, Vazquez-Borrego MC, Mahmood M, Gutierrez-Casado E, Pelke N, Guzman G, Subbaiah PV, Cordoba-Chacon J, Yakar S, Kineman RD. GH directly inhibits steatosis and liver injury in a sex-dependent and IGF1-independent manner. J Endocrinol 2021; 248:31-44. [PMID: 33112796 PMCID: PMC7785648 DOI: 10.1530/joe-20-0326] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022]
Abstract
A reduction in hepatocyte growth hormone (GH)-signaling promotes non-alcoholic fatty liver disease (NAFLD). However, debate remains as to the relative contribution of the direct effects of GH on hepatocyte function vs indirect effects, via alterations in insulin-like growth factor 1 (IGF1). To isolate the role of hepatocyte GH receptor (GHR) signaling, independent of changes in IGF1, mice with adult-onset, hepatocyte-specific GHR knockdown (aHepGHRkd) were treated with a vector expressing rat IGF1 targeted specifically to hepatocytes. Compared to GHR-intact mice, aHepGHRkd reduced circulating IGF1 and elevated GH. In male aHepGHRkd, the shift in IGF1/GH did not alter plasma glucose or non-esterified fatty acids (NEFA), but was associated with increased insulin, enhanced systemic lipid oxidation and reduced white adipose tissue (WAT) mass. Livers of male aHepGHRkd exhibited steatosis associated with increased de novo lipogenesis, hepatocyte ballooning and inflammation. In female aHepGHRkd, hepatic GHR protein levels were not detectable, but moderate levels of IGF1 were maintained, with minimal alterations in systemic metabolism and no evidence of steatosis. Reconstitution of hepatocyte IGF1 in male aHepGHRkd lowered GH and normalized insulin, whole body lipid utilization and WAT mass. However, IGF1 reconstitution did not reduce steatosis or eliminate liver injury. RNAseq analysis showed IGF1 reconstitution did not impact aHepGHRkd-induced changes in liver gene expression, despite changes in systemic metabolism. These results demonstrate the impact of aHepGHRkd is sexually dimorphic and the steatosis and liver injury observed in male aHepGHRkd mice is autonomous of IGF1, suggesting GH acts directly on the adult hepatocyte to control NAFLD progression.
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Affiliation(s)
- Andre Sarmento-Cabral
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mercedes del Rio-Moreno
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mari C. Vazquez-Borrego
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Mariyah Mahmood
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Elena Gutierrez-Casado
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Natalie Pelke
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Grace Guzman
- Department of Pathology, University of Illinois at Chicago,
College of Medicine, Chicago, IL
| | - Papasani V. Subbaiah
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Jose Cordoba-Chacon
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
| | - Shoshana Yakar
- Department of Molecular Pathobiology, New York University
College of Dentistry, New York, NY
| | - Rhonda D. Kineman
- Department of Medicine, Section of Endocrinology, Diabetes,
and Metabolism, University of Illinois at Chicago and Research and Development
Division, Jesse Brown VA Medical Center, Chicago, IL
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17
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Enkhtur A, Yoon JS, Lee CW. Factors increasing the risk of mortality and morbidity due to coronavirus infection in patients with metabolic syndrome. PRECISION AND FUTURE MEDICINE 2020. [DOI: 10.23838/pfm.2020.00121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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18
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Kopchick JJ, Berryman DE, Puri V, Lee KY, Jorgensen JOL. The effects of growth hormone on adipose tissue: old observations, new mechanisms. Nat Rev Endocrinol 2020; 16:135-146. [PMID: 31780780 PMCID: PMC7180987 DOI: 10.1038/s41574-019-0280-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/16/2019] [Indexed: 12/18/2022]
Abstract
The ability of growth hormone (GH) to induce adipose tissue lipolysis has been known for over five decades; however, the molecular mechanisms that mediate this effect and the ability of GH to inhibit insulin-stimulated glucose uptake have scarcely been documented. In this same time frame, our understanding of adipose tissue has evolved to reveal a complex structure with distinct types of adipocyte, depot-specific differences, a biologically significant extracellular matrix and important endocrine properties mediated by adipokines. All these aforementioned features, in turn, can influence lipolysis. In this Review, we provide a historical and current overview of the lipolytic effect of GH in humans, mice and cultured cells. More globally, we explain lipolysis in terms of GH-induced intracellular signalling and its effect on obesity, insulin resistance and lipotoxicity. In this regard, findings that define molecular mechanisms by which GH induces lipolysis are described. Finally, data are presented for the differential effect of GH on specific adipose tissue depots and on distinct classes of metabolically active adipocytes. Together, these cellular, animal and human studies reveal novel cellular phenotypes and molecular pathways regulating the metabolic effects of GH on adipose tissue.
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Affiliation(s)
- John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA.
- The Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA.
- Department of Biomedical Sciences, Ohio University College of Osteopathic Medicine, Athens, OH, USA.
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
- The Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA
- Department of Biomedical Sciences, Ohio University College of Osteopathic Medicine, Athens, OH, USA
| | - Vishwajeet Puri
- The Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA
- Department of Biomedical Sciences, Ohio University College of Osteopathic Medicine, Athens, OH, USA
| | - Kevin Y Lee
- The Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA
- Department of Biomedical Sciences, Ohio University College of Osteopathic Medicine, Athens, OH, USA
| | - Jens O L Jorgensen
- Department of Endocrinology and Diabetes, Aarhus University Hospital, Aarhus, Denmark
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19
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Zatterale F, Longo M, Naderi J, Raciti GA, Desiderio A, Miele C, Beguinot F. Chronic Adipose Tissue Inflammation Linking Obesity to Insulin Resistance and Type 2 Diabetes. Front Physiol 2020; 10:1607. [PMID: 32063863 PMCID: PMC7000657 DOI: 10.3389/fphys.2019.01607] [Citation(s) in RCA: 509] [Impact Index Per Article: 127.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 12/23/2019] [Indexed: 12/13/2022] Open
Abstract
Obesity is one of the major health burdens of the 21st century as it contributes to the growing prevalence of its related comorbidities, including insulin resistance and type 2 diabetes. Growing evidence suggests a critical role for overnutrition in the development of low-grade inflammation. Specifically, chronic inflammation in adipose tissue is considered a crucial risk factor for the development of insulin resistance and type 2 diabetes in obese individuals. The triggers for adipose tissue inflammation are still poorly defined. However, obesity-induced adipose tissue expansion provides a plethora of intrinsic signals (e.g., adipocyte death, hypoxia, and mechanical stress) capable of initiating the inflammatory response. Immune dysregulation in adipose tissue of obese subjects results in a chronic low-grade inflammation characterized by increased infiltration and activation of innate and adaptive immune cells. Macrophages are the most abundant innate immune cells infiltrating and accumulating into adipose tissue of obese individuals; they constitute up to 40% of all adipose tissue cells in obesity. In obesity, adipose tissue macrophages are polarized into pro-inflammatory M1 macrophages and secrete many pro-inflammatory cytokines capable of impairing insulin signaling, therefore promoting the progression of insulin resistance. Besides macrophages, many other immune cells (e.g., dendritic cells, mast cells, neutrophils, B cells, and T cells) reside in adipose tissue during obesity, playing a key role in the development of adipose tissue inflammation and insulin resistance. The association of obesity, adipose tissue inflammation, and metabolic diseases makes inflammatory pathways an appealing target for the treatment of obesity-related metabolic complications. In this review, we summarize the molecular mechanisms responsible for the obesity-induced adipose tissue inflammation and progression toward obesity-associated comorbidities and highlight the current therapeutic strategies.
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Affiliation(s)
- Federica Zatterale
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
| | - Michele Longo
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
| | - Jamal Naderi
- URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy.,Department of Environmental, Biological, and Pharmaceutical Sciences and Technologies, University of Campania Luigi Vanvitelli, Caserta, Italy
| | - Gregory Alexander Raciti
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
| | - Antonella Desiderio
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
| | - Claudia Miele
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
| | - Francesco Beguinot
- Department of Translational Medicine, University of Naples Federico II, Naples, Italy.,URT Genomic of Diabetes, Institute of Experimental Endocrinology and Oncology, National Research Council, Naples, Italy
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20
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King SE, Nilsson E, Beck D, Skinner MK. Adipocyte epigenetic alterations and potential therapeutic targets in transgenerationally inherited lean and obese phenotypes following ancestral exposures. Adipocyte 2019; 8:362-378. [PMID: 31755359 PMCID: PMC6948971 DOI: 10.1080/21623945.2019.1693747] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/30/2019] [Accepted: 11/11/2019] [Indexed: 01/01/2023] Open
Abstract
The incidence of obesity has increased dramatically over the past two decades with a prevalence of approximately 40% of the adult population within the United States. The current study examines the potential for transgenerational adipocyte (fat cell) epigenetic alterations. Adipocytes were isolated from the gonadal fat pad of the great-grand offspring F3 generation 1-year old rats ancestrally exposed to DDT (dichlorodiphenyltrichloroethane), atrazine, or vehicle control in order to obtain adipocytes for DNA methylation analysis. Observations indicate that there were differential DNA methylated regions (DMRs) in the adipocytes with the lean or obese phenotypes compared to control normal (non-obese or lean) populations. The comparison of epigenetic alterations indicated that there were substantial overlaps between the different treatment lineage groups for both the lean and obese phenotypes. Novel correlated genes and gene pathways associated with DNA methylation were identified, and may aid in the discovery of potential therapeutic targets for metabolic diseases such as obesity. Observations indicate that ancestral exposures during critical windows of development can induce the epigenetic transgenerational inheritance of DNA methylation changes in adipocytes that ultimately may contribute to an altered metabolic phenotype.
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Affiliation(s)
- Stephanie E. King
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Eric Nilsson
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Daniel Beck
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Michael K. Skinner
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
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21
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Zhang Y, Wang S, Zhao T, Yang L, Guo S, Shi Y, Zhang X, Zhou L, Ye L. Mono-2-ethylhexyl phthalate (MEHP) promoted lipid accumulation via JAK2/STAT5 and aggravated oxidative stress in BRL-3A cells. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 184:109611. [PMID: 31491605 DOI: 10.1016/j.ecoenv.2019.109611] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 08/21/2019] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
Mono-2-ethylhexyl phthalate (MEHP), as the major metabolite of Di-(2-ethylhexyl) phthalate (DEHP), can induce lipid accumulation in hepatocytes and further leads to non-alcoholic fatty liver disease (NAFLD), while the underlying mechanism is unclear. We aim to clarify the effects of JAK2/STAT5 pathway on lipid accumulation induced by MEHP and the role of oxidation stress in NAFLD. BRL-3A hepatocytes were exposed to MEHP (0, 10, 50, 100 and 200 μM) for 24 h and 48 h. Then the lipid droplets in cells were observed by Oil-Red-O staining and quantified by isopropyl alcohol. The levels of TG, SOD, TBARS, AST and ALT were all detected by commercial kits. RT-PCR was used to detect mRNA expression, and western blotting was used to detect the expression of proteins encoded by JAK2/STAT5 pathway genes and lipid metabolism-related genes. As a result, MEHP promoted the lipid synthesis and accumulation in BRL-3A cells. MEHP down-regulated the expression and inhibited the activation of JAK2/STAT5. Moreover, the lipid metabolism-related kinases levels were elevated after MEHP exposure. In addition, the SOD levels were gradually decreased and the TBARS levels were increased in MEHP-treated groups. The lipid metabolism-related proteins levels were correlated with the oxidation stress levels. Furthermore, the ALT and AST levels were elevated after MEHP exposure. Therefore, we concluded that MEHP led to lipid accumulation through inhibiting JAK2/STAT5 pathway, resulted in damaging liver parenchyma and NAFLD by aggravating oxidation stress.
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Affiliation(s)
- Yuezhu Zhang
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Shuyue Wang
- Department of Emergency, China-Japan Union Hospital, Jilin University, Changchun, China
| | - Tianyang Zhao
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Liwei Yang
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Shuangyu Guo
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Yanbin Shi
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Xueting Zhang
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China
| | - Liting Zhou
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China.
| | - Lin Ye
- Department of Occupational and Environmental Health, School of Public Health, Jilin University, Changchun, China.
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22
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Hjelholt AJ, Lee KY, Arlien-Søborg MC, Pedersen SB, Kopchick JJ, Puri V, Jessen N, Jørgensen JOL. Temporal patterns of lipolytic regulators in adipose tissue after acute growth hormone exposure in human subjects: A randomized controlled crossover trial. Mol Metab 2019; 29:65-75. [PMID: 31668393 PMCID: PMC6731350 DOI: 10.1016/j.molmet.2019.08.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/11/2019] [Accepted: 08/15/2019] [Indexed: 12/18/2022] Open
Abstract
Objective Growth hormone (GH) stimulates lipolysis, but the underlying mechanisms remain incompletely understood. We examined the effect of GH on the expression of lipolytic regulators in adipose tissue (AT). Methods In a randomized, placebo-controlled, cross-over study, nine men were examined after injection of 1) a GH bolus and 2) a GH-receptor antagonist (pegvisomant) followed by four AT biopsies. In a second study, eight men were examined in a 2 × 2 factorial design including GH infusion and 36-h fasting with AT biopsies obtained during a basal period and a hyperinsulinemic-euglycemic clamp. Expression of GH-signaling intermediates and lipolytic regulators were studied by PCR and western blotting. In addition, mechanistic experiments in mouse models and 3T3-L1 adipocytes were performed. Results The GH bolus increased circulating free fatty acids (p < 0.0001) together with phosphorylation of signal transducer and activator of transcription 5 (STAT5) (p < 0.0001) and mRNA expression of the STAT5-dependent genes cytokine-inducible SH2-containing protein (CISH) and IGF-1 in AT. This was accompanied by suppressed mRNA expression of G0/G1 switch gene 2 (G0S2) (p = 0.007) and fat specific protein 27 (FSP27) (p = 0.002) and upregulation of phosphatase and tensin homolog (PTEN) mRNA expression (p = 0.03). Suppression of G0S2 was also observed in humans after GH infusion and fasting, as well as in GH transgene mice, and in vitro studies suggested MEK-PPARγ signaling to be involved. Conclusions GH-induced lipolysis in human subjects in vivo is linked to downregulation of G0S2 and FSP27 and upregulation of PTEN in AT. Mechanistically, in vitro data suggest that GH acts via MEK to suppress PPARγ-dependent transcription of G0S2. ClinicalTrials.govNCT02782221 and NCT01209429. Acute GH exposure in human subjects in vivo stimulates lipolysis and release of FFA together with GH signaling in adipose tissue. GH-induced lipolysis is associated with suppression of G0S2 and FSP27 and upregulation of PTEN in human subjects in vivo. Inhibition of MEK and activation of PPARγ abrogate GH-induced suppression of G0S2 mRNA expression in vitro.
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Affiliation(s)
- Astrid Johannesson Hjelholt
- Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark; Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 82, 8200 Aarhus N, Denmark.
| | - Kevin Y Lee
- Heritage College of Osteopathic Medicine, Ohio University, 204 Grosvenor Hall, Athens, OH 45701, USA; The Diabetes Institute, Ohio University, Konneker Research Center 108, Athens, OH 45701, USA
| | - Mai Christiansen Arlien-Søborg
- Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark; Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 82, 8200 Aarhus N, Denmark
| | - Steen Bønløkke Pedersen
- Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Hedeager 3, 2., 8200 Aarhus N, Denmark
| | - John J Kopchick
- Heritage College of Osteopathic Medicine, Ohio University, 204 Grosvenor Hall, Athens, OH 45701, USA; The Edison Biotechnology Institute, Ohio University, Konneker Research Center, 172 Water Tower Dr., Athens, OH 45701, USA
| | - Vishwajeet Puri
- Heritage College of Osteopathic Medicine, Ohio University, 204 Grosvenor Hall, Athens, OH 45701, USA; The Diabetes Institute, Ohio University, Konneker Research Center 108, Athens, OH 45701, USA
| | - Niels Jessen
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Hedeager 3, 2., 8200 Aarhus N, Denmark; Department of Clinical Pharmacology, Aarhus University Hospital, Wilh. Meyers Allé 4, 8000 Aarhus C, Denmark; Department of Biomedicine, Aarhus University, Vennelyst Boulevard 4, 8000 Aarhus C, Denmark
| | - Jens Otto L Jørgensen
- Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark; Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 82, 8200 Aarhus N, Denmark
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23
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Corbit KC, Wilson CG, Lowe D, Tran JL, Vera NB, Clasquin M, Mattis AN, Weiss EJ. Adipocyte JAK2 mediates spontaneous metabolic liver disease and hepatocellular carcinoma. JCI Insight 2019; 5:131310. [PMID: 31393852 DOI: 10.1172/jci.insight.131310] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) are liver manifestations of the metabolic syndrome and can progress to hepatocellular carcinoma (HCC). Loss of Growth Hormone (GH) signaling is reported to predispose to NAFLD and NASH through direct actions on the liver. Here, we report that aged mice lacking hepatocyte Jak2 (JAK2L), an obligate transducer of Growth Hormone (GH) signaling, spontaneously develop the full spectrum of phenotypes found in patients with metabolic liver disease, beginning with insulin resistance and lipodystrophy and manifesting as NAFLD, NASH and even HCC, independent of dietary intervention. Remarkably, insulin resistance, metabolic liver disease, and carcinogenesis are prevented in JAK2L mice via concomitant deletion of adipocyte Jak2 (JAK2LA). Further, we demonstrate that GH increases hepatic lipid burden but does so indirectly via signaling through adipocyte JAK2. Collectively, these data establish adipocytes as the mediator of GH-induced metabolic liver disease and carcinogenesis. In addition, we report a new spontaneous model of NAFLD, NASH, and HCC that recapitulates the natural sequelae of human insulin resistance-associated disease progression. The work presented here suggests a attention be paid towards inhibition of adipocyte GH signaling as a therapeutic target of metabolic liver disease.
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Affiliation(s)
- Kevin C Corbit
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Camella G Wilson
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Dylan Lowe
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Jennifer L Tran
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Nicholas B Vera
- Cambridge Laboratories, Pfizer Global Research and Development, Pfizer Inc., Cambridge, Massachusetts, USA
| | - Michelle Clasquin
- Cambridge Laboratories, Pfizer Global Research and Development, Pfizer Inc., Cambridge, Massachusetts, USA
| | - Aras N Mattis
- Department of Pathology, UCSF, San Francisco, California, USA
| | - Ethan J Weiss
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
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24
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Chhabra Y, Nelson CN, Plescher M, Barclay JL, Smith AG, Andrikopoulos S, Mangiafico S, Waxman DJ, Brooks AJ, Waters MJ. Loss of growth hormone-mediated signal transducer and activator of transcription 5 (STAT5) signaling in mice results in insulin sensitivity with obesity. FASEB J 2019; 33:6412-6430. [PMID: 30779881 PMCID: PMC6463913 DOI: 10.1096/fj.201802328r] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Growth hormone (GH) has an important function as an insulin antagonist with elevated insulin sensitivity evident in humans and mice lacking a functional GH receptor (GHR). We sought the molecular basis for this sensitivity by utilizing a panel of mice possessing specific deletions of GHR signaling pathways. Metabolic clamps and glucose homeostasis tests were undertaken in these obese adult C57BL/6 male mice, which indicated impaired hepatic gluconeogenesis. Insulin sensitivity and glucose disappearance rate were enhanced in muscle and adipose of mice lacking the ability to activate the signal transducer and activator of transcription (STAT)5 via the GHR (Ghr-391-/-) as for GHR-null (GHR-/-) mice. These changes were associated with a striking inhibition of hepatic glucose output associated with altered glycogen metabolism and elevated hepatic glycogen content during unfed state. The enhanced hepatic insulin sensitivity was associated with increased insulin receptor β and insulin receptor substrate 1 activation along with activated downstream protein kinase B signaling cascades. Although phosphoenolpyruvate carboxykinase (Pck)-1 expression was unchanged, its inhibitory acetylation was elevated because of decreased sirtuin-2 expression, thereby promoting loss of PCK1. Loss of STAT5 signaling to defined chromatin immunoprecipitation targets would further increase lipogenesis, supporting hepatosteatosis while lowering glucose output. Finally, up-regulation of IL-15 expression in muscle, with increased secretion of adiponectin and fibroblast growth factor 1 from adipose tissue, is expected to promote insulin sensitivity.-Chhabra, Y., Nelson, C. N., Plescher, M., Barclay, J. L., Smith, A. G., Andrikopoulos, S., Mangiafico, S., Waxman, D. J., Brooks, A. J., Waters, M. J. Loss of growth hormone-mediated signal transducer and activator of transcription 5 (STAT5) signaling in mice results in insulin sensitivity with obesity.
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Affiliation(s)
- Yash Chhabra
- University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia.,Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Caroline N Nelson
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Monika Plescher
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.,Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Johanna L Barclay
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.,Mater Research Institute, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Aaron G Smith
- School of Biomedical Sciences, Institute of Health and Biomedical Innovation, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Sof Andrikopoulos
- Department of Medicine, The University of Melbourne, Victoria, Australia
| | | | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts, USA
| | - Andrew J Brooks
- University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia.,Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Michael J Waters
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
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25
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Glad CAM, Svensson PA, Nystrom FH, Jacobson P, Carlsson LMS, Johannsson G, Andersson-Assarsson JC. Expression of GHR and Downstream Signaling Genes in Human Adipose Tissue-Relation to Obesity and Weight Change. J Clin Endocrinol Metab 2019; 104:1459-1470. [PMID: 30541116 DOI: 10.1210/jc.2018-01036] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 12/07/2018] [Indexed: 01/05/2023]
Abstract
CONTEXT GH is a strong regulator of metabolism. In obesity, both GH secretion and adipose tissue GHR gene expression are decreased. More detailed information on the regulation of GHR, STAT3/5, and downstream-regulated genes in human adipose tissue during diet-induced weight loss and weight gain is lacking. OBJECTIVE The aim of the present study was to investigate the gene expression patterns of GHR and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway (JAK2, STAT3, STAT5A, and STAT5B) in human subcutaneous adipose tissue in relation to energy restriction and overfeeding. DESIGN, PATIENTS, AND INTERVENTIONS Tissue distribution was analyzed in a data set generated by RNA sequencing containing information on global expression in human tissues. Subcutaneous adipose tissue or adipocyte gene expression (measured by DNA microarrays) was investigated in the following settings: (i) individuals with obesity vs individuals with normal weight; (ii) energy restriction; and (iii) overfeeding. RESULTS GHR expression was decreased in subjects with obesity compared with subjects with normal weight (P < 0.001). It was increased in response to energy restriction and decreased in response to overfeeding (P = 0.015 and P = 0.030, respectively). STAT3 expression was increased in subjects with obesity (P < 0.001). It was decreased during energy restriction and increased during overfeeding (P = 0.004 and P = 0.006, respectively). STAT3-regulated genes showed an overall view of overexpression in obesity. CONCLUSIONS The results of the present study have shown that GHR, STAT3, and STAT3-regulated genes are dynamically, and reciprocally, regulated at the tissue level in response to energy restriction and overfeeding, suggesting that GH signaling is perturbed in obesity.
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Affiliation(s)
- Camilla A M Glad
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Endocrinology, Diabetes and Metabolism, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Per-Arne Svensson
- Department of Molecular and Clinical Medicine, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Health and Care Sciences at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik H Nystrom
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Peter Jacobson
- Department of Molecular and Clinical Medicine, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lena M S Carlsson
- Department of Molecular and Clinical Medicine, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Gudmundur Johannsson
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Endocrinology, Diabetes and Metabolism, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Johanna C Andersson-Assarsson
- Department of Molecular and Clinical Medicine, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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26
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CircScd1 Promotes Fatty Liver Disease via the Janus Kinase 2/Signal Transducer and Activator of Transcription 5 Pathway. Dig Dis Sci 2019; 64:113-122. [PMID: 30259280 DOI: 10.1007/s10620-018-5290-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 09/14/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases in affluent countries. Recent studies have reported that circular RNAs (circRNAs) are important regulators of hepatic steatosis. However, the role and mechanism of circRNA in NAFLD are poorly understood. AIMS This study is to reveal the role and mechanism of circRNA in NAFLD. METHODS Through NAFLD-related circRNA microarrays, we used real-time quantitative reverse transcription-polymerase chain reaction to screen circScd1 levels in control and test groups of mice fed a high-fat diet. RNA interference and over-expression plasmid vectors were used to manipulate the expression of circScd1, and the biological effects were evaluated by oil red staining, triglyceride detection, and western blot analysis. RESULTS CircScd1 expression was significantly lower in NAFLD tissues than in control tissues. Moreover, over-expression of circScd1 significantly inhibited the formation of lipid droplets. Western blot analyses showed that the protein levels of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 5 (STAT5) were significantly increased. However, knockdown of circScd1 significantly promoted the degree of hepatocellular lipidosis and reduced the expression levels of JAK2 and STAT5. CONCLUSIONS Aberrant expression of circScd1 affects the extent of hepatocellular lipidosis in NAFLD and promotes fatty liver disease via the JAK2/STAT5 pathway.
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27
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List EO, Berryman DE, Buchman M, Parker C, Funk K, Bell S, Duran-Ortiz S, Qian Y, Young JA, Wilson C, Slyby J, McKenna S, Jensen EA, Kopchick JJ. Adipocyte-Specific GH Receptor-Null (AdGHRKO) Mice Have Enhanced Insulin Sensitivity With Reduced Liver Triglycerides. Endocrinology 2019; 160:68-80. [PMID: 30462209 PMCID: PMC6304108 DOI: 10.1210/en.2018-00850] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 11/09/2018] [Indexed: 12/16/2022]
Abstract
Global GH receptor-null or knockout (GHRKO) mice have been extensively studied owing to their unique phenotype (dwarf and obese but remarkably insulin sensitive and long-lived). To better understand the influence of adipose tissue (AT) on the GHRKO phenotype, we previously generated fat-specific GHRKO (FaGHRKO) mice using the adipocyte protein-2 (aP2) promoter driving Cre expression. Unlike global GHRKO mice, FaGHRKO mice are larger than control mice and have an increase in white AT (WAT) mass and adipocyte size as well as an increase in brown AT mass. FaGHRKO mice also have an unexpected increase in IGF-1, decrease in adiponectin, no change in insulin sensitivity or liver triglyceride content, and a decreased lifespan. Extensive analysis of the aP2 promoter/enhancer by multiple laboratories has revealed expression in nonadipose tissues, confounding interpretation of results. In the current study, we used the adiponectin promoter/enhancer to drive Cre expression, which better targets mature adipocytes, and generated a new line of adipocyte-specific GHRKO (AdGHRKO) mice. AdGHRKO mice have an increase in adipocyte size and WAT depot mass in all depots except male perigonadal, a WAT accumulation pattern similar to FaGHRKO mice. Likewise, adiponectin levels and WAT fibrosis are decreased in both tissue-specific mouse lines. However, unlike FaGHRKO mice, AdGHRKO mice have no change in IGF-1 levels, improved glucose homeostasis, and reduced liver triglycerides. Thus, AdGHRKO mice should be valuable for future studies assessing the contribution of adipocyte GHR signaling in long-term health and lifespan.
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Affiliation(s)
- Edward O List
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- Department of Specialty Medicine, Heritage College of Osteopathic Medicine, Athens, Ohio
- Correspondence: Edward O. List, PhD, Edison Biotechnology Institute, Ohio University, 218 Konneker Research Labs, 172 Watertower Drive, Athens, Ohio 45701. E-mail:
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Athens, Ohio
| | - Mathew Buchman
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- College of Health Sciences and Professions, Ohio University, Athens, Ohio
| | - Caitlin Parker
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- College of Health Sciences and Professions, Ohio University, Athens, Ohio
| | - Kevin Funk
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
| | - Stephen Bell
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Athens, Ohio
| | | | - Yanrong Qian
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
| | | | - Cody Wilson
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
| | - Julie Slyby
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
| | | | | | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, Ohio
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Athens, Ohio
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28
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Sharma R, Luong Q, Sharma VM, Harberson M, Harper B, Colborn A, Berryman DE, Jessen N, Jørgensen JOL, Kopchick JJ, Puri V, Lee KY. Growth hormone controls lipolysis by regulation of FSP27 expression. J Endocrinol 2018; 239:289-301. [PMID: 30400015 PMCID: PMC6226059 DOI: 10.1530/joe-18-0282] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 09/24/2018] [Indexed: 01/10/2023]
Abstract
Growth hormone (GH) has long been known to stimulate lipolysis and insulin resistance; however, the molecular mechanisms underlying these effects are unknown. In the present study, we demonstrate that GH acutely induces lipolysis in cultured adipocytes. This effect is secondary to the reduced expression of a negative regulator of lipolysis, fat-specific protein 27 (FSP27; aka Cidec) at both the mRNA and protein levels. These effects are mimicked in vivo as transgenic overexpression of GH leads to a reduction of FSP27 expression. Mechanistically, we show GH modulation of FSP27 expression is mediated through activation of both MEK/ERK- and STAT5-dependent intracellular signaling. These two molecular pathways interact to differentially manipulate peroxisome proliferator-activated receptor gamma activity (PPARγ) on the FSP27 promoter. Furthermore, overexpression of FSP27 is sufficient to fully suppress GH-induced lipolysis and insulin resistance in cultured adipocytes. Taken together, these data decipher a molecular mechanism by which GH acutely regulates lipolysis and insulin resistance in adipocytes.
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Affiliation(s)
- Rita Sharma
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Quyen Luong
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Vishva M. Sharma
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Mitchell Harberson
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Brian Harper
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Andrew Colborn
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Darlene E. Berryman
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Niels Jessen
- Research Laboratory for Biochemical Pathology, Aarhus University Hospital, Aarhus, Denmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Biomedicine, Aarhus University, Denmark
| | - Jens Otto Lunde Jørgensen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Medical Research Laboratory, Aarhus University, Aarhus, Denmark
| | - John J. Kopchick
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
- Edison Biotechnology Institute, Ohio University, Athens, OH
| | - Vishwajeet Puri
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
| | - Kevin Y. Lee
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH
- The Diabetes Institute, Ohio University, Athens, OH
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29
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Cordoba-Chacon J, Sarmento-Cabral A, del Rio-Moreno M, Diaz-Ruiz A, Subbaiah PV, Kineman RD. Adult-Onset Hepatocyte GH Resistance Promotes NASH in Male Mice, Without Severe Systemic Metabolic Dysfunction. Endocrinology 2018; 159:3761-3774. [PMID: 30295789 PMCID: PMC6202859 DOI: 10.1210/en.2018-00669] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/01/2018] [Indexed: 12/20/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD), which includes nonalcoholic steatohepatitis (NASH), is associated with reduced GH input/signaling, and GH therapy is effective in the reduction/resolution of NAFLD/NASH in selected patient populations. Our laboratory has focused on isolating the direct vs indirect effects of GH in preventing NAFLD/NASH. We reported that chow-fed, adult-onset, hepatocyte-specific, GH receptor knockdown (aHepGHRkd) mice rapidly (within 7 days) develop steatosis associated with increased hepatic de novo lipogenesis (DNL), independent of changes in systemic metabolic function. In this study, we report that 6 months after induction of aHepGHRkd early signs of NASH develop, which include hepatocyte ballooning, inflammation, signs of mild fibrosis, and elevated plasma alanine aminotransferase. These changes occur in the presence of enhanced systemic lipid utilization, without evidence of white adipose tissue lipolysis, indicating that the liver injury that develops after aHepGHRkd is due to hepatocyte-specific loss of GH signaling and not due to secondary defects in systemic metabolic function. Specifically, enhanced hepatic DNL is sustained with age in aHepGHRkd mice, associated with increased hepatic markers of lipid uptake/re-esterification. Because hepatic DNL is a hallmark of NAFLD/NASH, these studies suggest that enhancing hepatocyte GH signaling could represent an effective therapeutic target to reduce DNL and treat NASH.
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Affiliation(s)
- Jose Cordoba-Chacon
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Andre Sarmento-Cabral
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Mercedes del Rio-Moreno
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC)/University of Cordoba, Cordoba, Spain
| | - Alberto Diaz-Ruiz
- Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
- Nutritional Interventions Group, Precision Nutrition and Aging, Institute IMDEA Food, Madrid, Spain
| | - Papasani V Subbaiah
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Rhonda D Kineman
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
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30
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Kaltenecker D, Themanns M, Mueller KM, Spirk K, Suske T, Merkel O, Kenner L, Luís A, Kozlov A, Haybaeck J, Müller M, Han X, Moriggl R. Hepatic growth hormone - JAK2 - STAT5 signalling: Metabolic function, non-alcoholic fatty liver disease and hepatocellular carcinoma progression. Cytokine 2018; 124:154569. [PMID: 30389231 DOI: 10.1016/j.cyto.2018.10.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/05/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022]
Abstract
The rising prevalence of obesity came along with an increase in associated metabolic disorders in Western countries. Non-alcoholic fatty liver disease (NAFLD) represents the hepatic manifestation of the metabolic syndrome and is linked to primary stages of liver cancer development. Growth hormone (GH) regulates various vital processes such as energy supply and cellular regeneration. In addition, GH regulates various aspects of liver physiology through activating the Janus kinase (JAK) 2- signal transducer and activator of transcription (STAT) 5 pathway. Consequently, disrupted GH - JAK2 - STAT5 signaling in the liver alters hepatic lipid metabolism and is associated with NAFLD development in humans and mouse models. Interestingly, while STAT5 as well as JAK2 deficiency correlates with hepatic lipid accumulation, recent studies suggest that these proteins have unique ambivalent functions in chronic liver disease progression and tumorigenesis. In this review, we focus on the consequences of altered GH - JAK2 - STAT5 signaling for hepatic lipid metabolism and liver cancer development with an emphasis on lessons learned from genetic knockout models.
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Affiliation(s)
- Doris Kaltenecker
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
| | - Madeleine Themanns
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria; Medical University of Vienna, Vienna, Austria
| | - Kristina M Mueller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
| | - Katrin Spirk
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria; Medical University of Vienna, Vienna, Austria
| | - Tobias Suske
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Olaf Merkel
- Department of Clinical Pathology, Medical University of Vienna, Vienna, Austria
| | - Lukas Kenner
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria; Department of Clinical Pathology, Medical University of Vienna, Vienna, Austria; Institute of Laboratory Animal Pathology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Andreia Luís
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria
| | - Andrey Kozlov
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria
| | - Johannes Haybaeck
- Diagnostic & Research Center for Molecular BioMedicine, Institute of Pathology, Medical University of Graz, Austria; Department of Pathology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany; Department of Pathology, Medical University of Innsbruck, Innsbruck, Austria
| | - Mathias Müller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Xiaonan Han
- Key Laboratory of Human Disease Comparative Medicine, the Ministry of Health; Institute of Laboratory Animal Sciences (ILAS), Chinese Academy of Medical Science (CAMS) and Peking Union Medical College (PUMC), Beijing, PR China; Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, OH, USA
| | - Richard Moriggl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria; Medical University of Vienna, Vienna, Austria.
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Henry RK. Growth Hormone Deficiency and Nonalcoholic Fatty Liver Disease with Insights from Humans and Animals: Pediatric Implications. Metab Syndr Relat Disord 2018; 16:507-513. [PMID: 30346875 DOI: 10.1089/met.2018.0056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In addition to its growth promoting role, growth hormone (GH) has a significant effect on intermediary metabolism in the well state. Despite the latter fact, pediatric practitioners are usually focused on the growth promoting aspects of GH as opposed to those metabolic. In recent years various animal and human studies (in adults mainly) and clinical reports in children have repeatedly shown the association of GH deficiency (GHD) and fatty liver disease. Based on this well-identified association, despite a lack of studies involving children, it behooves the pediatric clinician to ensure that not only patients with GHD are appropriately treated but also that adolescents even beyond the period of linear growth should be appropriately transitioned to adult GH therapy should this be appropriate.
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Affiliation(s)
- Rohan K Henry
- Division of Endocrinology, Department of Pediatrics, Nationwide Children's Hospital/The Ohio State University College of Medicine , Columbus, Ohio
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32
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Bergan-Roller HE, Sheridan MA. The growth hormone signaling system: Insights into coordinating the anabolic and catabolic actions of growth hormone. Gen Comp Endocrinol 2018; 258:119-133. [PMID: 28760716 DOI: 10.1016/j.ygcen.2017.07.028] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 07/19/2017] [Accepted: 07/27/2017] [Indexed: 12/16/2022]
Abstract
Although growth hormone (GH) is a multifunctional factor that coordinates various aspects of feeding, reproduction, osmoregulation, and immune system function, perhaps two of its most studied actions are the regulation of growth and metabolism, particularly lipid metabolism. In this review, we describe the major growth-promoting and lipid metabolic actions of GH and then discuss how the GH system regulates these actions. Numerous intrinsic and extrinsic factors provide information about the metabolic status of the organism and influence the production of release of GH. The actions of GH are mediated by GH receptors (GHR), which are widely distributed among tissues. Teleosts possess multiple forms of GHRs that arose through the evolution of this group. Modulation of tissue responsiveness to GH is regulated by molecular and functional expression of GHRs, and in teleosts GHR subtypes, by various factors that reflect the metabolic and growth status of the organism, including nutritional state. The action of GH is propagated by the linkage of GHRs to several cellular effector systems, including JAK-STAT, ERK, PI3K-Akt, and PKC. The differential activation of these pathways, which is governed by nutrient status, underlies GH stimulation of growth or GH stimulation of lipolysis. Taken together, the multi-functional actions of GH are determined by the distribution and abundance of GHRs (and GHR subtypes in teleosts) as well as by the GHR-effector system linkages.
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Affiliation(s)
| | - Mark A Sheridan
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409 USA.
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33
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Corbit KC, Camporez JPG, Edmunds LR, Tran JL, Vera NB, Erion DM, Deo RC, Perry RJ, Shulman GI, Jurczak MJ, Weiss EJ. Adipocyte JAK2 Regulates Hepatic Insulin Sensitivity Independently of Body Composition, Liver Lipid Content, and Hepatic Insulin Signaling. Diabetes 2018; 67:208-221. [PMID: 29203511 PMCID: PMC5780061 DOI: 10.2337/db17-0524] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 11/15/2017] [Indexed: 01/07/2023]
Abstract
Disruption of hepatocyte growth hormone (GH) signaling through disruption of Jak2 (JAK2L) leads to fatty liver. Previously, we demonstrated that development of fatty liver depends on adipocyte GH signaling. We sought to determine the individual roles of hepatocyte and adipocyte Jak2 on whole-body and tissue insulin sensitivity and liver metabolism. On chow, JAK2L mice had hepatic steatosis and severe whole-body and hepatic insulin resistance. However, concomitant deletion of Jak2 in hepatocytes and adipocytes (JAK2LA) completely normalized insulin sensitivity while reducing liver lipid content. On high-fat diet, JAK2L mice had hepatic steatosis and insulin resistance despite protection from diet-induced obesity. JAK2LA mice had higher liver lipid content and no protection from obesity but retained exquisite hepatic insulin sensitivity. AKT activity was selectively attenuated in JAK2L adipose tissue, whereas hepatic insulin signaling remained intact despite profound hepatic insulin resistance. Therefore, JAK2 in adipose tissue is epistatic to liver with regard to insulin sensitivity and responsiveness, despite fatty liver and obesity. However, hepatocyte autonomous JAK2 signaling regulates liver lipid deposition under conditions of excess dietary fat. This work demonstrates how various tissues integrate JAK2 signals to regulate insulin/glucose and lipid metabolism.
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Affiliation(s)
- Kevin C Corbit
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | | | - Lia R Edmunds
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Jennifer L Tran
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | - Nicholas B Vera
- Cardiovascular and Metabolic Diseases, Pfizer, Cambridge, MA
| | - Derek M Erion
- Cardiovascular and Metabolic Diseases, Pfizer, Cambridge, MA
| | - Rahul C Deo
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | - Rachel J Perry
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Gerald I Shulman
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT
- Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Ethan J Weiss
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
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Dodington DW, Desai HR, Woo M. JAK/STAT - Emerging Players in Metabolism. Trends Endocrinol Metab 2018; 29:55-65. [PMID: 29191719 DOI: 10.1016/j.tem.2017.11.001] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 11/06/2017] [Accepted: 11/06/2017] [Indexed: 02/07/2023]
Abstract
The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway is crucial for transducing signals from a variety of metabolically relevant hormones and cytokines including growth hormone, leptin, erythropoietin, IL4, IL6 and IFNγ. A growing body of evidence suggests that this pathway is dysregulated in the context of obesity and metabolic disease. Recent development of animal models has been instrumental in identifying the role of JAK/STAT signaling in the peripheral metabolic organs including adipose, liver, muscle, pancreas, and the immune system. In this review we summarize current knowledge about the function of JAK/STAT proteins in the regulation of metabolism, and highlight new potential therapeutic targets for the treatment of obesity and diabetes.
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Affiliation(s)
- David W Dodington
- Toronto General Hospital Research Institute, University Health Network, Toronto, M5G 1L7, Canada
| | - Harsh R Desai
- Toronto General Hospital Research Institute, University Health Network, Toronto, M5G 1L7, Canada
| | - Minna Woo
- Toronto General Hospital Research Institute, University Health Network, Toronto, M5G 1L7, Canada; Division of Endocrinology and Metabolism, Department of Medicine, University Health Network and University of Toronto, Toronto, M5G 2C4, Canada.
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35
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Liu Z, Han T, Werner H, Rosen CJ, Schaffler MB, Yakar S. Reduced Serum IGF-1 Associated With Hepatic Osteodystrophy Is a Main Determinant of Low Cortical but Not Trabecular Bone Mass. J Bone Miner Res 2018; 33:123-136. [PMID: 28902430 PMCID: PMC5771972 DOI: 10.1002/jbmr.3290] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/31/2017] [Accepted: 09/06/2017] [Indexed: 12/11/2022]
Abstract
Hepatic osteodystrophy is multifactorial in its pathogenesis. Numerous studies have shown that impairments of the hepatic growth hormone/insulin-like growth factor-1 axis (GH/IGF-1) are common in patients with non-alcoholic fatty liver disease, chronic viral hepatitis, liver cirrhosis, and chronic cholestatic liver disease. Moreover, these conditions are also associated with low bone mineral density (BMD) and greater fracture risk, particularly in cortical bone sites. Hence, we addressed whether disruptions in the GH/IGF-1 axis were causally related to the low bone mass in states of chronic liver disease using a mouse model of liver-specific GH-receptor (GHR) gene deletion (Li-GHRKO). These mice exhibit chronic hepatic steatosis, local inflammation, and reduced BMD. We then employed a crossing strategy to restore liver production of IGF-1 via hepatic IGF-1 transgene (HIT). The resultant Li-GHRKO-HIT mouse model allowed us to dissect the roles of liver-derived IGF-1 in the pathogenesis of osteodystrophy during liver disease. We found that hepatic IGF-1 restored cortical bone acquisition, microarchitecture, and mechanical properties during growth in Li-GHRKO-HIT mice, which was maintained during aging. However, trabecular bone volume was not restored in the Li-GHRKO-HIT mice. We found increased bone resorption indices in vivo as well as increased basal reactive oxygen species and increased mitochondrial stress in osteoblast cultures from Li-GHRKO and the Li-GHRKO-HIT compared with control mice. Changes in systemic markers such as inflammatory cytokines, osteoprotegerin, osteopontin, parathyroid hormone, osteocalcin, or carboxy-terminal collagen cross-links could not fully account for the diminished trabecular bone in the Li-GHRKO-HIT mice. Thus, the reduced serum IGF-1 associated with hepatic osteodystrophy is a main determinant of low cortical but not trabecular bone mass. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Zhongbo Liu
- David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology New York University College of Dentistry New York, NY 10010-4086
| | - Tianzhen Han
- David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology New York University College of Dentistry New York, NY 10010-4086
| | - Haim Werner
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | | | | | - Shoshana Yakar
- David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology New York University College of Dentistry New York, NY 10010-4086
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Abstract
Adipose tissue represents a large volume of biologically active tissue that exerts substantial systemic effects in health and disease. Alcohol consumption can profoundly disturb the normal functions of adipose tissue by inducing adipocyte death and altering secretion of adipokines, pro-inflammatory mediators and free fatty acids from adipose tissue, which have important direct and indirect effects on the pathogenesis of alcoholic liver disease (ALD). Cessation of alcohol intake quickly reverses inflammatory changes in adipose tissue, and pharmacological treatment that normalizes adipose tissue function improves experimental ALD. Obesity exacerbates liver injury induced by chronic or binge alcohol consumption, and obesity and alcohol can synergize to increase risk of ALD and progression. Physicians who care for individuals with ALD should be aware of the effects of adipose tissue dysfunction on liver function, and consider strategies to manage obesity and insulin resistance. This Review examines the effect of alcohol on adiposity and adipose tissue and the relationship between alcohol, adipose tissue and the liver.
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37
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Tetrahydrobenzothiophene carboxamides: Beyond the kinase domain and into the fatty acid realm. Bioorg Med Chem Lett 2017; 27:4462-4466. [DOI: 10.1016/j.bmcl.2017.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 08/01/2017] [Accepted: 08/03/2017] [Indexed: 11/21/2022]
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Macrophage JAK2 deficiency protects against high-fat diet-induced inflammation. Sci Rep 2017; 7:7653. [PMID: 28794431 PMCID: PMC5550513 DOI: 10.1038/s41598-017-07923-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 07/03/2017] [Indexed: 02/06/2023] Open
Abstract
During obesity, macrophages can infiltrate metabolic tissues, and contribute to chronic low-grade inflammation, and mediate insulin resistance and diabetes. Recent studies have elucidated the metabolic role of JAK2, a key mediator downstream of various cytokines and growth factors. Our study addresses the essential role of macrophage JAK2 in the pathogenesis to obesity-associated inflammation and insulin resistance. During high-fat diet (HFD) feeding, macrophage-specific JAK2 knockout (M-JAK2−/−) mice gained less body weight compared to wildtype littermate control (M-JAK2+/+) mice and were protected from HFD-induced systemic insulin resistance. Histological analysis revealed smaller adipocytes and qPCR analysis showed upregulated expression of some adipogenesis markers in visceral adipose tissue (VAT) of HFD-fed M-JAK2−/− mice. There were decreased crown-like structures in VAT along with reduced mRNA expression of some macrophage markers and chemokines in liver and VAT of HFD-fed M-JAK2−/− mice. Peritoneal macrophages from M-JAK2−/− mice and Jak2 knockdown in macrophage cell line RAW 264.7 also showed lower levels of chemokine expression and reduced phosphorylated STAT3. However, leptin-dependent effects on augmenting chemokine expression in RAW 264.7 cells did not require JAK2. Collectively, our findings show that macrophage JAK2 deficiency improves systemic insulin sensitivity and reduces inflammation in VAT and liver in response to metabolic stress.
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Mota de Sá P, Richard AJ, Hang H, Stephens JM. Transcriptional Regulation of Adipogenesis. Compr Physiol 2017; 7:635-674. [PMID: 28333384 DOI: 10.1002/cphy.c160022] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adipocytes are the defining cell type of adipose tissue. Once considered a passive participant in energy storage, adipose tissue is now recognized as a dynamic organ that contributes to several important physiological processes, such as lipid metabolism, systemic energy homeostasis, and whole-body insulin sensitivity. Therefore, understanding the mechanisms involved in its development and function is of great importance. Adipocyte differentiation is a highly orchestrated process which can vary between different fat depots as well as between the sexes. While hormones, miRNAs, cytoskeletal proteins, and many other effectors can modulate adipocyte development, the best understood regulators of adipogenesis are the transcription factors that inhibit or promote this process. Ectopic expression and knockdown approaches in cultured cells have been widely used to understand the contribution of transcription factors to adipocyte development, providing a basis for more sophisticated in vivo strategies to examine adipogenesis. To date, over two dozen transcription factors have been shown to play important roles in adipocyte development. These transcription factors belong to several families with many different DNA-binding domains. While peroxisome proliferator-activated receptor gamma (PPARγ) is undoubtedly the most important transcriptional modulator of adipocyte development in all types of adipose tissue, members of the CCAAT/enhancer-binding protein, Krüppel-like transcription factor, signal transducer and activator of transcription, GATA, early B cell factor, and interferon-regulatory factor families also regulate adipogenesis. The importance of PPARγ activity is underscored by several covalent modifications that modulate its activity and its ability to modulate adipocyte development. This review will primarily focus on the transcriptional control of adipogenesis in white fat cells and on the mechanisms involved in this fine-tuned developmental process. © 2017 American Physiological Society. Compr Physiol 7:635-674, 2017.
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Affiliation(s)
- Paula Mota de Sá
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Allison J Richard
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Hardy Hang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Jacqueline M Stephens
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
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40
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Donepudi AC, Boehme S, Li F, Chiang JY. G-protein-coupled bile acid receptor plays a key role in bile acid metabolism and fasting-induced hepatic steatosis in mice. Hepatology 2017; 65:813-827. [PMID: 27351453 PMCID: PMC5195921 DOI: 10.1002/hep.28707] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 06/12/2016] [Accepted: 06/20/2016] [Indexed: 12/25/2022]
Abstract
UNLABELLED Bile acids are signaling molecules that play a critical role in regulation of hepatic metabolic homeostasis by activating nuclear farnesoid X receptor (Fxr) and membrane G-protein-coupled receptor (Takeda G-protein-coupled receptor 5; Tgr5). The role of FXR in regulation of bile acid synthesis and hepatic metabolism has been studied extensively. However, the role of TGR5 in hepatic metabolism has not been explored. The liver plays a central role in lipid metabolism, and impaired response to fasting and feeding contributes to steatosis and nonalcoholic fatty liver and obesity. We have performed a detailed analysis of gallbladder bile acid and lipid metabolism in Tgr5-/- mice in both free-fed and fasted conditions. Lipid profiles of serum, liver and adipose tissues, bile acid composition, energy metabolism, and messenger RNA and protein expression of the genes involved in lipid metabolism were analyzed. Results showed that deficiency of the Tgr5 gene in mice alleviated fasting-induced hepatic lipid accumulation. Expression of liver oxysterol 7α-hydroxylase in the alternative bile acid synthesis pathway was reduced. Analysis of gallbladder bile acid composition showed marked increase of taurocholic acid and decrease of tauro-α and β-muricholic acid in Tgr5-/- mice. Tgr5-/- mice had increased hepatic fatty acid oxidation rate and decreased hepatic fatty acid uptake. Interestingly, fasting induction of fibroblast growth factor 21 in liver was attenuated. In addition, fasted Tgr5-/- mice had increased activation of hepatic growth hormone-signal transducer and activator of transcription 5 (GH-Stat5) signaling compared to wild-type mice. CONCLUSION TGR5 may play a role in determining bile acid composition and in fasting-induced hepatic steatosis through a novel mechanism involving activation of the GH-Stat5 signaling pathway. (Hepatology 2017;65:813-827).
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Affiliation(s)
- Ajay C. Donepudi
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Shannon Boehme
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Feng Li
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - John Y.L. Chiang
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
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Corbit KC, Camporez JPG, Tran JL, Wilson CG, Lowe DA, Nordstrom SM, Ganeshan K, Perry RJ, Shulman GI, Jurczak MJ, Weiss EJ. Adipocyte JAK2 mediates growth hormone-induced hepatic insulin resistance. JCI Insight 2017; 2:e91001. [PMID: 28194444 DOI: 10.1172/jci.insight.91001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
For nearly 100 years, growth hormone (GH) has been known to affect insulin sensitivity and risk of diabetes. However, the tissue governing the effects of GH signaling on insulin and glucose homeostasis remains unknown. Excess GH reduces fat mass and insulin sensitivity. Conversely, GH insensitivity (GHI) is associated with increased adiposity, augmented insulin sensitivity, and protection from diabetes. Here, we induce adipocyte-specific GHI through conditional deletion of Jak2 (JAK2A), an obligate transducer of GH signaling. Similar to whole-body GHI, JAK2A mice had increased adiposity and extreme insulin sensitivity. Loss of adipocyte Jak2 augmented hepatic insulin sensitivity and conferred resistance to diet-induced metabolic stress without overt changes in circulating fatty acids. While GH injections induced hepatic insulin resistance in control mice, the diabetogenic action was absent in JAK2A mice. Adipocyte GH signaling directly impinged on both adipose and hepatic insulin signal transduction. Collectively, our results show that adipose tissue governs the effects of GH on insulin and glucose homeostasis. Further, we show that JAK2 mediates liver insulin sensitivity via an extrahepatic, adipose tissue-dependent mechanism.
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Affiliation(s)
- Kevin C Corbit
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | | | - Jennifer L Tran
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Camella G Wilson
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Dylan A Lowe
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Sarah M Nordstrom
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | - Kirthana Ganeshan
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
| | | | - Gerald I Shulman
- Department of Internal Medicine.,Cellular and Molecular Physiology, and.,Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Michael J Jurczak
- Department of Medicine, Division of Endocrinology and Metabolism, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Ethan J Weiss
- Cardiovascular Research Institute, UCSF, San Francisco, California, USA
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Kaltenecker D, Mueller KM, Benedikt P, Feiler U, Themanns M, Schlederer M, Kenner L, Schweiger M, Haemmerle G, Moriggl R. Adipocyte STAT5 deficiency promotes adiposity and impairs lipid mobilisation in mice. Diabetologia 2017; 60:296-305. [PMID: 27858140 PMCID: PMC6518368 DOI: 10.1007/s00125-016-4152-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 10/12/2016] [Indexed: 01/04/2023]
Abstract
AIMS/HYPOTHESIS Dysfunction of lipid metabolism in white adipose tissue can substantially interfere with health and quality of life, for example in obesity and associated metabolic diseases. Therefore, it is important to characterise pathways that regulate lipid handling in adipocytes and determine how they affect metabolic homeostasis. Components of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway are involved in adipocyte physiology and pathophysiology. However, the exact physiological importance of the STAT family member STAT5 in white adipose tissue is yet to be determined. Here, we aimed to delineate adipocyte STAT5 functions in the context of lipid metabolism in white adipose tissue. METHODS We generated an adipocyte specific knockout of Stat5 in mice using the Adipoq-Cre recombinase transgene followed by in vivo and in vitro biochemical and molecular studies. RESULTS Adipocyte-specific deletion of Stat5 resulted in increased adiposity, while insulin resistance and gluconeogenic capacity was decreased, indicating that glucose metabolism can be improved by interfering with adipose STAT5 function. Basal lipolysis and fasting-induced lipid mobilisation were diminished upon STAT5 deficiency, which coincided with reduced levels of the rate-limiting lipase of triacylglycerol hydrolysis, adipose triglyceride lipase (ATGL, encoded by Pnpla2) and its coactivator comparative gene identification 58 (CGI-58). In a mechanistic analysis, we identified a functional STAT5 response element within the Pnpla2 promoter, indicating that Pnpla2 is transcriptionally regulated by STAT5. CONCLUSIONS/INTERPRETATION Our findings reveal an essential role for STAT5 in maintaining lipid homeostasis in white adipose tissue and provide a rationale for future studies into the potential of STAT5 manipulation to improve outcomes in metabolic diseases.
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Affiliation(s)
- Doris Kaltenecker
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Kristina M Mueller
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Pia Benedikt
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Ursula Feiler
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Madeleine Themanns
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Michaela Schlederer
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Lukas Kenner
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
- Unit of Pathology of Laboratory Animals, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria.
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria.
- Medical University of Vienna, Vienna, Austria.
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The Association Between IGF-1 Levels and the Histologic Severity of Nonalcoholic Fatty Liver Disease. Clin Transl Gastroenterol 2017; 8:e217. [PMID: 28125073 PMCID: PMC5288606 DOI: 10.1038/ctg.2016.72] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 12/07/2016] [Indexed: 12/13/2022] Open
Abstract
Objectives: The mechanisms responsible for the development of nonalcoholic fatty liver disease (NAFLD) and progression to nonalcoholic steatohepatitis (NASH) are incompletely understood. Growing evidence suggests that growth hormone (GH) and insulin-like growth factor-1 (IGF-1) may have roles in the development and progression of NAFLD. We hypothesized that lower serum IGF-1 levels would be associated with increased liver fat accumulation, inflammation, and fibrosis in a group of meticulously phenotyped obese subjects with liver biopsies. Methods: A retrospective, cross-sectional study was performed at Massachusetts General Hospital, Boston, MA, USA and St. Mary's Hospital, Richmond, VA, USA. Liver biopsies were performed in 142 subjects during NAFLD work-up or bariatric surgery and were graded by a single, blinded pathologist. Main outcome measures included liver histology and serum IGF-1. Results: Mean age was 52±10 years and body mass index (BMI) was 43±9 kg/m2. Mean serum IGF-1 was lower in subjects with lobular inflammation (112±47 vs. 136±57 ng/ml, P=0.01), hepatocyte ballooning (115±48 vs. 135±57 ng/ml, P=0.05), higher fibrosis stage (stage 2–4 vs. 0–1; 96±40 vs. 125±51 ng/ml, P=0.005), and NASH (109±45 vs. 136±57 ng/ml, P=0.002). All results remained significant after controlling for age, BMI, and a diagnosis of diabetes, and all but hepatocyte ballooning (trend, P=0.06) remained significant after excluding individuals with cirrhosis. Steatosis was not significantly associated with mean serum IGF-1 levels. Conclusions: Low serum IGF-1 levels are associated with increased histologic severity of NAFLD when rigorously controlled for age, BMI, the presence of diabetes, and after the exclusion of subjects with cirrhosis. Further investigation is warranted to determine the differential effects of GH and IGF-1 on the development and progression of NAFLD, which could further elucidate pathophysiology and identify therapeutic targets.
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44
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Liu Z, Cordoba-Chacon J, Kineman RD, Cronstein BN, Muzumdar R, Gong Z, Werner H, Yakar S. Growth Hormone Control of Hepatic Lipid Metabolism. Diabetes 2016; 65:3598-3609. [PMID: 27679560 PMCID: PMC5127251 DOI: 10.2337/db16-0649] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/20/2016] [Indexed: 12/15/2022]
Abstract
In humans, low levels of growth hormone (GH) and its mediator, IGF-1, associate with hepatic lipid accumulation. In mice, congenital liver-specific ablation of the GH receptor (GHR) results in reductions in circulating IGF-1 and hepatic steatosis, associated with systemic insulin resistance. Due to the intricate relationship between GH and IGF-1, the relative contribution of each hormone to the development of hepatic steatosis is unclear. Our goal was to dissect the mechanisms by which hepatic GH resistance leads to steatosis and overall insulin resistance, independent of IGF-1. We have generated a combined mouse model with liver-specific ablation of GHR in which we restored liver IGF-1 expression via the hepatic IGF-1 transgene. We found that liver GHR ablation leads to increases in lipid uptake, de novo lipogenesis, hyperinsulinemia, and hyperglycemia accompanied with severe insulin resistance and increased body adiposity and serum lipids. Restoration of IGF-1 improved overall insulin sensitivity and lipid profile in serum and reduced body adiposity, but was insufficient to protect against steatosis-induced hepatic inflammation or oxidative stress. We conclude that the impaired metabolism in states of GH resistance results from direct actions of GH on lipid uptake and de novo lipogenesis, whereas its actions on extrahepatic tissues are mediated by IGF-1.
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Affiliation(s)
- Zhongbo Liu
- Department of Basic Science & Craniofacial Biology, David B. Kriser Dental Center, NYU College of Dentistry, New York, NY
| | - Jose Cordoba-Chacon
- Research and Development, Jesse Brown VA Medical Center, Chicago, IL
- Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL
| | - Rhonda D Kineman
- Research and Development, Jesse Brown VA Medical Center, Chicago, IL
- Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL
| | | | - Radhika Muzumdar
- Division of Pediatric Endocrinology, Diabetes and Metabolism Consultation, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Zhenwei Gong
- Division of Pediatric Endocrinology, Diabetes and Metabolism Consultation, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Haim Werner
- Department of Human Molecular Genetics and Biochemistry, The Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel
| | - Shoshana Yakar
- Department of Basic Science & Craniofacial Biology, David B. Kriser Dental Center, NYU College of Dentistry, New York, NY
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Hepatic Deletion of Janus Kinase 2 Counteracts Oxidative Stress in Mice. Sci Rep 2016; 6:34719. [PMID: 27713471 PMCID: PMC5054456 DOI: 10.1038/srep34719] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/19/2016] [Indexed: 12/13/2022] Open
Abstract
Genetic deletion of the tyrosine kinase JAK2 or the downstream transcription factor STAT5 in liver impairs growth hormone (GH) signalling and thereby promotes fatty liver disease. Hepatic STAT5 deficiency accelerates liver tumourigenesis in presence of high GH levels. To determine whether the upstream kinase JAK2 exerts similar functions, we crossed mice harbouring a hepatocyte-specific deletion of JAK2 (JAK2Δhep) to GH transgenic mice (GHtg) and compared them to GHtgSTAT5Δhep mice. Similar to GHtgSTAT5Δhep mice, JAK2 deficiency resulted in severe steatosis in the GHtg background. However, in contrast to STAT5 deficiency, loss of JAK2 significantly delayed liver tumourigenesis. This was attributed to: (i) activation of STAT3 in STAT5-deficient mice, which was prevented by JAK2 deficiency and (ii) increased detoxification capacity of JAK2-deficient livers, which diminished oxidative damage as compared to GHtgSTAT5Δhep mice, despite equally severe steatosis and reactive oxygen species (ROS) production. The reduced oxidative damage in JAK2-deficient livers was linked to increased expression and activity of glutathione S-transferases (GSTs). Consistent with genetic deletion of Jak2, pharmacological inhibition and siRNA-mediated knockdown of Jak2 led to significant upregulation of Gst isoforms and to reduced hepatic oxidative DNA damage. Therefore, blocking JAK2 function increases detoxifying GSTs in hepatocytes and protects against oxidative liver damage.
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46
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Gurzov EN, Stanley WJ, Pappas EG, Thomas HE, Gough DJ. The JAK/STAT pathway in obesity and diabetes. FEBS J 2016; 283:3002-15. [PMID: 26972840 DOI: 10.1111/febs.13709] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 02/14/2016] [Accepted: 03/08/2016] [Indexed: 12/12/2022]
Abstract
Diabetes mellitus are complex, multi-organ metabolic pathologies characterized by hyperglycemia. Emerging evidence shows that the highly conserved and potent JAK/STAT signaling pathway is required for normal homeostasis, and, when dysregulated, contributes to the development of obesity and diabetes. In this review, we analyze the role of JAK/STAT activation in the brain, liver, muscle, fat and pancreas, and how this affects the course of the disease. We also consider the therapeutic implications of targeting the JAK/STAT pathway in treatment of obesity and diabetes.
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Affiliation(s)
- Esteban N Gurzov
- St Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Australia
| | - William J Stanley
- St Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Australia
| | - Evan G Pappas
- St Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Australia
| | - Helen E Thomas
- St Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Fitzroy, Australia
| | - Daniel J Gough
- Hudson Institute of Medical Research, Clayton, Australia.,Department of Molecular and Translational Science, Monash University, Clayton, Australia
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Romero CJ, Wolfe A, Law YY, Costelloe CZ, Miller R, Wondisford F, Radovick S. Altered somatotroph feedback regulation improves metabolic efficiency and limits adipose deposition in male mice. Metabolism 2016; 65:557-68. [PMID: 26975547 PMCID: PMC5331908 DOI: 10.1016/j.metabol.2015.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/18/2015] [Accepted: 11/25/2015] [Indexed: 11/22/2022]
Abstract
Several transgenic mouse models with disruption in the growth hormone (GH) axis support the role of GH in augmenting metabolic homeostasis. Specifically, interest has focused on GH's lipolytic properties and ability to affect adipose deposition. Furthermore, both GH and insulin growth factor 1 (IGF-1) may also play a direct or indirect role in adipose development. The somatotroph insulin-like growth factor-1 receptor knockout (SIGFRKO) mouse with only a modest increase in serum GH and IGF-1 demonstrates less adipose tissue than controls. In order to characterize the metabolic phenotype of SIGFRKO mice, histologic analysis of fat depots confirmed a smaller average diameter of adipocytes in the SIGFRKO mice compared to controls. These changes were accompanied by an increase in lipolytic gene expression in fat depots. Indirect calorimetry performed on 6-8week old male mice and again at 25weeks of age demonstrated that SIGFRKO mice, at both ages, had a higher VO2 and increased energy expenditure when compared with controls. The calculated respiratory exchange ratio (RER) was lower in the younger SIGFRKO mice compared to controls. No differences in food consumption or in either ambulatory or total activity were seen between SIGFRKO and control mice in either age group. These studies highlight the role of GH in adipose deposition and its influence on the expression of lipolytic genes resulting in an altered metabolic state, thus providing a mechanism for the decrease in weight gain seen in the SIGFRKO mouse model.
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Affiliation(s)
- Christopher J Romero
- Division of Pediatric Endocrinology and Diabetes, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1616, New York, NY 10029.
| | - Andrew Wolfe
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - Yi Ying Law
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - ChenChen Z Costelloe
- Division of Pediatric Endocrinology, Johns Hopkins University, School of Medicine, 600 North Wolfe Street, CSMC 4-106, Baltimore, MD 21287
| | - Ryan Miller
- Division of Pediatric Endocrinology, University of Maryland Medical Center, 22. S. Greene St., Baltimore, MD 21201
| | - Fredric Wondisford
- Robert Wood Johnson Medical School, Rutgers Biomedical and Health Sciences, New Brunswick, NJ 08901
| | - Sally Radovick
- Robert Wood Johnson Medical School, Rutgers Biomedical and Health Sciences, New Brunswick, NJ 08901
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Shi SY, Zhang W, Luk CT, Sivasubramaniyam T, Brunt JJ, Schroer SA, Desai HR, Majerski A, Woo M. JAK2 promotes brown adipose tissue function and is required for diet- and cold-induced thermogenesis in mice. Diabetologia 2016; 59:187-196. [PMID: 26515423 DOI: 10.1007/s00125-015-3786-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 09/28/2015] [Indexed: 11/29/2022]
Abstract
AIMS/HYPOTHESIS Non-shivering thermogenesis in adipose tissue can be activated by excessive energy intake or following cold exposure. The molecular mechanisms regulating this activation have not been fully elucidated. The Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathway mediates the signal transduction of numerous hormones and growth factors that regulate adipose tissue development and function, and may play a role in adaptive thermogenesis. METHODS We analysed mRNA and protein levels of uncoupling protein 1 (UCP1) and JAK2 in different adipose depots in response to metabolic and thermal stress. The in vivo role of JAK2 in adaptive thermogenesis was examined using mice with adipocyte-specific Jak2 deficiency (A-Jak2 KO). RESULTS We show in murine brown adipose tissue (BAT) that JAK2 is upregulated together with UCP1 in response to high-fat diet (HFD) feeding and cold exposure. In contrast to white adipose tissue, where JAK2 was dispensable for UCP1 induction, we identified an essential role for BAT JAK2 in diet- and cold-induced thermogenesis via mediating the thermogenic response to β-adrenergic stimulation. Accordingly, A-Jak2 KO mice were unable to upregulate BAT UCP1 following a HFD or after cold exposure. Therefore, A-Jak2 KO mice were cold intolerant and susceptible to HFD-induced obesity and diabetes. CONCLUSIONS/INTERPRETATION Taken together, our results suggest that JAK2 plays a critical role in BAT function and adaptive thermogenesis. Targeting the JAK-STAT pathway may be a novel therapeutic approach for the treatment of obesity and related metabolic disorders.
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Affiliation(s)
- Sally Yu Shi
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Wei Zhang
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Department of Endocrinology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, China
| | - Cynthia T Luk
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Tharini Sivasubramaniyam
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Jara J Brunt
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Stephanie A Schroer
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
| | - Harsh R Desai
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Alexandra Majerski
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7
| | - Minna Woo
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Toronto, ON, Canada, M5G 1L7.
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada.
- Division of Endocrinology, Department of Medicine, Toronto General Hospital, University Health Network, University of Toronto, Toronto, ON, Canada.
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49
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Abstract
In adipocytes the hydrolysis of TAG to produce fatty acids and glycerol under fasting conditions or times of elevated energy demands is tightly regulated by neuroendocrine signals, resulting in the activation of lipolytic enzymes. Among the classic regulators of lipolysis, adrenergic stimulation and the insulin-mediated control of lipid mobilisation are the best known. Initially, hormone-sensitive lipase (HSL) was thought to be the rate-limiting enzyme of the first lipolytic step, while we now know that adipocyte TAG lipase is the key enzyme for lipolysis initiation. Pivotal, previously unsuspected components have also been identified at the protective interface of the lipid droplet surface and in the signalling pathways that control lipolysis. Perilipin, comparative gene identification-58 (CGI-58) and other proteins of the lipid droplet surface are currently known to be key regulators of the lipolytic machinery, protecting or exposing the TAG core of the droplet to lipases. The neuroendocrine control of lipolysis is prototypically exerted by catecholaminergic stimulation and insulin-induced suppression, both of which affect cyclic AMP levels and hence the protein kinase A-mediated phosphorylation of HSL and perilipin. Interestingly, in recent decades adipose tissue has been shown to secrete a large number of adipokines, which exert direct effects on lipolysis, while adipocytes reportedly express a wide range of receptors for signals involved in lipid mobilisation. Recently recognised mediators of lipolysis include some adipokines, structural membrane proteins, atrial natriuretic peptides, AMP-activated protein kinase and mitogen-activated protein kinase. Lipolysis needs to be reanalysed from the broader perspective of its specific physiological or pathological context since basal or stimulated lipolytic rates occur under diverse conditions and by different mechanisms.
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50
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Shi SY, Luk CT, Brunt JJ, Sivasubramaniyam T, Lu SY, Schroer SA, Woo M. Adipocyte-specific deficiency of Janus kinase (JAK) 2 in mice impairs lipolysis and increases body weight, and leads to insulin resistance with ageing. Diabetologia 2014; 57:1016-26. [PMID: 24531222 DOI: 10.1007/s00125-014-3185-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 01/21/2014] [Indexed: 12/14/2022]
Abstract
AIMS/HYPOTHESIS The growing obesity epidemic necessitates a better understanding of adipocyte biology and its role in metabolism. The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway mediates signalling by numerous cytokines and hormones that regulate adipocyte function, illustrating the physiological importance of adipose JAK-STAT. The aim of this study was to investigate potential roles of adipocyte JAK2, an essential player in the JAK-STAT pathway, in adipocyte biology and metabolism. METHODS We generated adipocyte-specific Jak2 knockout (A-Jak2 KO) mice using the Cre-loxP system with Cre expression driven by the Ap2 (also known as Fabp4) promoter. RESULTS Starting at 2-3 months of age, male and female A-Jak2 KO mice gradually gained more body weight than control littermates primarily due to increased adiposity. This was associated with reduced energy expenditure in A-Jak2 KO mice. In perigonadal adipose tissue, the expression of numerous genes involved in lipid metabolism was differentially regulated. In addition, adipose tissue from A-Jak2 KO mice displayed impaired lipolysis in response to isoprenaline, growth hormone and leptin stimulation, suggesting that adipose JAK2 directly modulates the lipolytic program. Impaired lipid homeostasis was also associated with disrupted adipokine secretion. Accordingly, while glucose metabolism was normal at 2 months of age, by 5-6 months of age, A-Jak2 KO mice had whole-body insulin resistance. CONCLUSIONS/INTERPRETATION Our results suggest that adipocyte JAK2 plays a critical role in the regulation of adipocyte biology and whole-body metabolism. Targeting of the JAK-STAT pathway could be a novel therapeutic option for the treatment of obesity and type 2 diabetes.
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Affiliation(s)
- Sally Yu Shi
- Toronto General Research Institute, 101 College Street, MaRS Centre/TMDT, Room 10-363, Toronto, ON, Canada, M5G 1L7
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