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The Hormone FGF21 Stimulates Water Drinking in Response to Ketogenic Diet and Alcohol. Cell Metab 2018; 27:1338-1347.e4. [PMID: 29657029 PMCID: PMC5990458 DOI: 10.1016/j.cmet.2018.04.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 02/02/2018] [Accepted: 04/02/2018] [Indexed: 01/05/2023]
Abstract
Alcohol and ketogenic diets increase water consumption. Here, we show that the hormone FGF21 is required for this drinking response in mice. Circulating levels of FGF21 are increased by alcohol consumption in humans and by both alcohol and ketogenic diets in mice. Pharmacologic administration of FGF21 stimulates water drinking behavior in mice within 2 hr. Concordantly, mice lacking FGF21 fail to increase water intake in response to either alcohol or a ketogenic diet. The effect of FGF21 on drinking is mediated in part by SIM1-positive neurons of the hypothalamus and is inhibited by β-adrenergic receptor antagonists. Given that FGF21 also is known to suppress alcohol intake in favor of pure water, this work identifies FGF21 as a fundamental neurotropic hormone that governs water balance in response to specific nutrient stresses that can cause dehydration.
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BonDurant LD, Potthoff MJ. Fibroblast Growth Factor 21: A Versatile Regulator of Metabolic Homeostasis. Annu Rev Nutr 2018; 38:173-196. [PMID: 29727594 DOI: 10.1146/annurev-nutr-071816-064800] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is an endocrine hormone derived from the liver that exerts pleiotropic effects on the body to maintain overall metabolic homeostasis. During the past decade, there has been an enormous effort made to understand the physiological roles of FGF21 in regulating metabolism and to identify the mechanism for its potent pharmacological effects to reverse diabetes and obesity. Through both human and rodent studies, it is now evident that FGF21 levels are dynamically regulated by nutrient sensing, and consequently FGF21 functions as a critical regulator of nutrient homeostasis. In addition, recent studies using new genetic and molecular tools have provided critical insight into the actions of this endocrine factor. This review examines the numerous functions of FGF21 and highlights the therapeutic potential of FGF21-targeted pathways for treating metabolic disease.
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Affiliation(s)
- Lucas D BonDurant
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
| | - Matthew J Potthoff
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
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Søberg S, Andersen ES, Dalsgaard NB, Jarlhelt I, Hansen NL, Hoffmann N, Vilsbøll T, Chenchar A, Jensen M, Grevengoed TJ, Trammell SAJ, Knop FK, Gillum MP. FGF21, a liver hormone that inhibits alcohol intake in mice, increases in human circulation after acute alcohol ingestion and sustained binge drinking at Oktoberfest. Mol Metab 2018; 11:96-103. [PMID: 29627377 PMCID: PMC6001399 DOI: 10.1016/j.molmet.2018.03.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE Excessive alcohol consumption is a leading cause of global morbidity and mortality. However, knowledge of the biological factors that influence ad libitum alcohol intake may be incomplete. Two large studies recently linked variants in the KLB locus with levels of alcohol intake in humans. KLB encodes β-klotho, co-receptor for the liver-derived hormone fibroblast growth factor 21 (FGF21). In mice, FGF21 reduces alcohol intake, and human Fgf21 variants are enriched among heavy drinkers. Thus, the liver may limit alcohol consumption by secreting FGF21. However, whether full-length, active plasma FGF21 (FGF21 (1-181)) levels in humans increase acutely or sub-chronically in response to alcohol ingestion is uncertain. METHODS We recruited 10 healthy, fasted male subjects to receive an oral water or alcohol bolus with concurrent blood sampling for FGF21 (1-181) measurement in plasma. In addition, we measured circulating FGF21 (1-181) levels, liver stiffness, triglyceride, and other metabolic parameters in three healthy Danish men before and after consuming an average of 22.6 beers/person/day (4.4 g/kg/day of ethanol) for three days during Oktoberfest 2017 in Munich, Germany. We further correlated fasting FGF21 (1-181) levels in 49 healthy, non-alcoholic subjects of mixed sex with self-reports of alcohol-related behaviors, emotional responses, and problems. Finally, we characterized the effect of recombinant human FGF21 injection on ad libitum alcohol intake in mice. RESULTS We show that alcohol ingestion (25.3 g or ∼2.5 standard drinks) acutely increases plasma levels of FGF21 (1-181) 3.4-fold in fasting humans. We also find that binge drinking for three days at Oktoberfest is associated with a 2.1-fold increase in baseline FGF21 (1-181) levels, in contrast to minor deteriorations in metabolic and hepatic biomarkers. However, basal FGF21 (1-181) levels were not correlated with differences in alcohol-related behaviors, emotional responses, or problems in our non-alcoholic subjects. Finally, we show that once-daily injection of recombinant human FGF21 reduces ad libitum alcohol intake by 21% in mice. CONCLUSIONS FGF21 (1-181) is markedly increased in circulation by both acute and sub-chronic alcohol intake in humans, and reduces alcohol intake in mice. These observations are consistent with a role for FGF21 as an endocrine inhibitor of alcohol appetite in humans.
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Affiliation(s)
- Susanna Søberg
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; The Center of Inflammation and Metabolism and the Center for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Emilie S Andersen
- Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels B Dalsgaard
- Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Ida Jarlhelt
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nina L Hansen
- Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Nina Hoffmann
- Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Tina Vilsbøll
- Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anne Chenchar
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michal Jensen
- The Center of Inflammation and Metabolism and the Center for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Trisha J Grevengoed
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sam A J Trammell
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Clinical Metabolic Physiology, Steno Diabetes Center Copenhagen, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Matthew P Gillum
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Wu G, Liu Y, Liu Y, Zhang L, Zhao H, Liu L, Zhao C, Feng W. FGF 21 deficiency slows gastric emptying and reduces initial blood alcohol concentration in mice exposed to acute alcohol in fasting state. Biochem Biophys Res Commun 2018; 497:46-50. [PMID: 29448103 DOI: 10.1016/j.bbrc.2018.01.189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Accepted: 01/31/2018] [Indexed: 12/18/2022]
Abstract
Excess alcohol consumption can lead to alcoholic liver disease. Fibroblast growth factor 21 (FGF21) is a metabolic regulator with multiple physiologic functions. Previous study demonstrated that FGF21 deficiency exacerbated alcohol-induced liver injury and exogenous FGF21 administration protected liver from chronic alcohol-induced injury. In this study, we aimed to explore the role of FGF21 in alcohol metabolism in mice. FGF21 knockout (KO) mice and the wild type(WT) control mice were divided into two groups and fasted for 24 h followed by a bonus of alcohol treatment at a dose of 5 g/kg body weight via gavage. Serum alcohol concentration was measured after gavage at 0.5, 2, 3, 4 and 6 h, respectively. At the end, gastric and liver tissues were collected. Serum alcohol concentration of KO mice was significantly lower than that of WT at 0.5 h after alcohol expose. There were no significant differences in alcohol dehydrogenase (ADH) activity and aldehyde dehydrogenase 2 (ALDH2) activity in gastric and liver tissues between WT and the KO mice. However, gastric emptying time of KO mice was much longer than that of WT mice. In addition, the intestinal permeability and serum GLP-1 level of KO mice were significantly higher than that of WT mice. These results suggest that FGF21 deficiency slow gastric emptying rate and indirectly influence initial alcohol metabolism in mice exposed to acute alcohol. Our findings provide additional information for understanding the gastrointestinal mechanism of alcoholic liver disease and other alcohol use disorders.
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Affiliation(s)
- Guicheng Wu
- Department of Hepatology, Chongqing Three Gorges Central Hospital, Chongqing, 404000, China; Alcohol Research Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
| | - Yanlong Liu
- Alcohol Research Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA; School of Pharmacy, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Yunhuan Liu
- Alcohol Research Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Lihua Zhang
- Alcohol Research Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Haiyang Zhao
- Institute of Virology, Wenzhou University, Wenzhou, Zhejiang, 325027, China
| | - Liming Liu
- Institute of Virology, Wenzhou University, Wenzhou, Zhejiang, 325027, China
| | - Cuiqing Zhao
- Institute of Virology, Wenzhou University, Wenzhou, Zhejiang, 325027, China
| | - Wenke Feng
- Alcohol Research Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA; School of Pharmacy, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; Institute of Virology, Wenzhou University, Wenzhou, Zhejiang, 325027, China.
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Kema VH, Khan I, Kapur S, Mandal P. Evaluating the effect of diallyl sulfide on regulation of inflammatory mRNA expression in 3T3L1 adipocytes and RAW 264.7 macrophages during ethanol treatment. Drug Chem Toxicol 2018; 41:302-313. [PMID: 29319385 DOI: 10.1080/01480545.2017.1405969] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Diallyl sulfide (DAS) has been studied extensively for its alleged role as an anticancer and protective agent. Alcohol influences and effects on human health have been extensively studied. However, investigations toward developing and testing therapeutic agents that can reduce the tissue injury caused by ethanol are scarce. In this backdrop, this study was designed to explore the potential effect of DAS in reducing alcohol induced damage of 3T3L1 adipocytes and RAW 264.7 macrophages. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay was performed to determine the DAS effect on cell viability. Reactive oxygen species (ROS) production was assessed by flow cytometer. Expression of inflammatory genes was studied by the qRT-PCR method. Our study results showed that DAS at concentrations less than 200 μM was not toxic to the cells and the viability of ethanol-exposed 3T3L1 adipocyte cells was found to be significantly increased when ethanol-exposed cells were treated with DAS. Further, treatment of ethanol-exposed 3T3L1 cells with 100 μM DAS for 24 h was found to reduce ethanol induced ROS production, expression of pro-inflammatory cytokines, and enhance anti-inflammatory cytokine production in the cells. Also, 100 μM DAS was found to increase the expression of M2 phenotype-specific genes in ethanol-exposed RAW 264.7 macrophage cells. Further, 100 μM DAS also improved the levels of lipid accumulation in 3T3L1 adipocytes that was down-regulated by ethanol exposure. Taken together, our study results imply that DAS may be effective in reducing ethanol induced injury of cells thereby suggesting its potential to be used in drug formulations.
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Affiliation(s)
- Venkata Harini Kema
- a Department of Biological Sciences , BITS Pilani, Hyderabad Campus , Hyderabad , India
| | - Imran Khan
- a Department of Biological Sciences , BITS Pilani, Hyderabad Campus , Hyderabad , India
| | - Suman Kapur
- a Department of Biological Sciences , BITS Pilani, Hyderabad Campus , Hyderabad , India
| | - Palash Mandal
- a Department of Biological Sciences , BITS Pilani, Hyderabad Campus , Hyderabad , India.,b Department of Biological Sciences , P D Patel Institute of Applied Sciences, Charotar University of Science and Technology , Changa , India
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Ramadori P, Cubero FJ, Liedtke C, Trautwein C, Nevzorova YA. Alcohol and Hepatocellular Carcinoma: Adding Fuel to the Flame. Cancers (Basel) 2017; 9:cancers9100130. [PMID: 28946672 PMCID: PMC5664069 DOI: 10.3390/cancers9100130] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 02/06/2023] Open
Abstract
Primary tumors of the liver represent the fifth most common type of cancer in the world and the third leading cause of cancer-related death. Case-control studies from different countries report that chronic ethanol consumption is associated with an approximately 2-fold increased odds ratio for hepatocellular carcinoma (HCC). Despite the substantial epidemiologic data in humans demonstrating that chronic alcohol consumption is a major risk factor for HCC development, the pathways causing alcohol-induced liver cancer are poorly understood. In this overview, we summarize the epidemiological evidence for the association between alcohol and liver cancer, review the genetic, oncogenic, and epigenetic factors that drive HCC development synergistically with ethanol intake and discuss the essential molecular and metabolic pathways involved in alcohol-induced liver tumorigenesis.
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Affiliation(s)
- Pierluigi Ramadori
- Department of Internal Medicine III, University Hospital RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
| | - Francisco Javier Cubero
- Department of Immunology, Complutense University School of Medicine, Madrid 28040, Spain.
- 13 de Octubre Health Research Institute (imas12), Madrid 28041, Spain.
| | - Christian Liedtke
- Department of Internal Medicine III, University Hospital RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
| | - Christian Trautwein
- Department of Internal Medicine III, University Hospital RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
| | - Yulia A Nevzorova
- Department of Internal Medicine III, University Hospital RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
- Department of Animal Physiology II, Faculty of Biology, Complutense University, Madrid 28040, Spain.
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Ter Horst KW, Gilijamse PW, Demirkiran A, van Wagensveld BA, Ackermans MT, Verheij J, Romijn JA, Nieuwdorp M, Maratos-Flier E, Herman MA, Serlie MJ. The FGF21 response to fructose predicts metabolic health and persists after bariatric surgery in obese humans. Mol Metab 2017; 6:1493-1502. [PMID: 29107295 PMCID: PMC5681276 DOI: 10.1016/j.molmet.2017.08.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 08/24/2017] [Accepted: 08/30/2017] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE Fructose consumption has been implicated in the development of obesity and insulin resistance. Emerging evidence shows that fibroblast growth factor 21 (FGF21) has beneficial effects on glucose, lipid, and energy metabolism and may also mediate an adaptive response to fructose ingestion. Fructose acutely stimulates circulating FGF21 consistent with a hormonal response. We aimed to evaluate whether fructose-induced FGF21 secretion is linked to metabolic outcomes in obese humans before and after bariatric surgery-induced weight loss. METHODS We recruited 40 Roux-en-Y gastric bypass patients and assessed the serum FGF21 response to fructose (75-g fructose tolerance test) and basal and insulin-mediated glucose and lipid fluxes during a 2-step hyperinsulinemic-euglycemic clamp with infusion of [6,6-2H2] glucose and [1,1,2,3,3-2H5] glycerol. Liver biopsies were obtained during bariatric surgery. Nineteen subjects underwent the same assessments at 1-year follow-up. RESULTS Serum FGF21 increased 3-fold at 120 min after fructose ingestion and returned to basal levels at 300 min. Neither basal FGF21 nor the fructose-FGF21 response correlated with liver fat content or liver histopathology, but increased levels were associated with elevated endogenous glucose production, increased lipolysis, and peripheral/muscle insulin resistance. At 1-year follow-up, subjects had lost 28 ± 6% of body weight and improved in all metabolic outcomes, but fructose-stimulated FGF21 dynamics did not markedly differ from the pre-surgical state. The association between increased basal and stimulated FGF21 levels with poor metabolic health was no longer present after weight loss. CONCLUSIONS Fructose ingestion in obese humans stimulates FGF21 secretion, and this response is related to systemic metabolism. Further studies are needed to establish if FGF21 signaling is (patho)physiologically involved in fructose metabolism and metabolic health.
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Affiliation(s)
- Kasper W Ter Horst
- Department of Endocrinology and Metabolism, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Pim W Gilijamse
- Department of Endocrinology and Metabolism, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Ahmet Demirkiran
- Department of Surgery, Red Cross Hospital, Vondellaan 13, 1942LE Beverwijk, The Netherlands
| | | | - Mariette T Ackermans
- Department of Clinical Chemistry, Laboratory of Endocrinology, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Joanne Verheij
- Department of Pathology, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Johannes A Romijn
- Department of Medicine, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Max Nieuwdorp
- Department of Vascular Medicine, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands; Department of Internal Medicine, VU University Medical Center, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands; Institute for Cardiovascular Research, VU University Medical Center, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Eleftheria Maratos-Flier
- Division of Endocrinology and Metabolism, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Center for Life Sciences, Boston, MA 02215, USA
| | - Mark A Herman
- Division of Endocrinology, Metabolism and Nutrition, Duke University School of Medicine, 300 N. Duke Street, Carmichael Building, Durham, NC 27701, USA
| | - Mireille J Serlie
- Department of Endocrinology and Metabolism, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands.
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Salminen A, Kaarniranta K, Kauppinen A. Regulation of longevity by FGF21: Interaction between energy metabolism and stress responses. Ageing Res Rev 2017; 37:79-93. [PMID: 28552719 DOI: 10.1016/j.arr.2017.05.004] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/28/2017] [Accepted: 05/18/2017] [Indexed: 12/11/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is a hormone-like member of FGF family which controls metabolic multiorgan crosstalk enhancing energy expenditure through glucose and lipid metabolism. In addition, FGF21 acts as a stress hormone induced by endoplasmic reticulum stress and dysfunctions of mitochondria and autophagy in several tissues. FGF21 also controls stress responses and metabolism by modulating the functions of somatotropic axis and hypothalamic-pituitary-adrenal (HPA) pathway. FGF21 is a potent longevity factor coordinating interactions between energy metabolism and stress responses. Recent studies have revealed that FGF21 treatment can alleviate many age-related metabolic disorders, e.g. atherosclerosis, obesity, type 2 diabetes, and some cardiovascular diseases. In addition, transgenic mice overexpressing FGF21 have an extended lifespan. However, chronic metabolic and stress-related disorders involving inflammatory responses can provoke FGF21 resistance and thus disturb healthy aging process. First, we will describe the role of FGF21 in interorgan energy metabolism and explain how its functions as a stress hormone can improve healthspan. Next, we will examine both the induction of FGF21 expression via the integrated stress response and the molecular mechanism through which FGF21 enhances healthy aging. Finally, we postulate that FGF21 resistance, similarly to insulin resistance, jeopardizes human healthspan and accelerates the aging process.
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Abdul-Wahed A, Guilmeau S, Postic C. Sweet Sixteenth for ChREBP: Established Roles and Future Goals. Cell Metab 2017; 26:324-341. [PMID: 28768172 DOI: 10.1016/j.cmet.2017.07.004] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 06/01/2017] [Accepted: 07/12/2017] [Indexed: 12/25/2022]
Abstract
With the identification of ChREBP in 2001, our interest in understanding the molecular control of carbohydrate sensing has surged. While ChREBP was initially studied as a master regulator of lipogenesis in liver and fat tissue, it is now clear that ChREBP functions as a central metabolic coordinator in a variety of cell types in response to environmental and hormonal signals, with wide implications in health and disease. Celebrating its sweet sixteenth birthday, we review here the current knowledge about the function and regulation of ChREBP throughout usual and less explored tissues, to recapitulate ChREBP's role as a whole-body glucose sensor.
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Affiliation(s)
- Aya Abdul-Wahed
- Inserm, U1016, Institut Cochin, 75014 Paris, France; CNRS UMR 8104, 75014 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France
| | - Sandra Guilmeau
- Inserm, U1016, Institut Cochin, 75014 Paris, France; CNRS UMR 8104, 75014 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France
| | - Catherine Postic
- Inserm, U1016, Institut Cochin, 75014 Paris, France; CNRS UMR 8104, 75014 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France.
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Gao B, Xu MJ, Bertola A, Wang H, Zhou Z, Liangpunsakul S. Animal Models of Alcoholic Liver Disease: Pathogenesis and Clinical Relevance. Gene Expr 2017; 17:173-186. [PMID: 28411363 PMCID: PMC5500917 DOI: 10.3727/105221617x695519] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Alcoholic liver disease (ALD), a leading cause of chronic liver injury worldwide, comprises a range of disorders including simple steatosis, steatohepatitis, cirrhosis, and hepatocellular carcinoma. Over the last five decades, many animal models for the study of ALD pathogenesis have been developed. Recently, a chronic-plus-binge ethanol feeding model was reported. This model induces significant steatosis, hepatic neutrophil infiltration, and liver injury. A clinically relevant model of high-fat diet feeding plus binge ethanol was also developed, which highlights the risk of excessive binge drinking in obese/overweight individuals. All of these models recapitulate some features of the different stages of ALD and have been widely used by many investigators to study the pathogenesis of ALD and to test for therapeutic drugs/components. However, these models are somewhat variable, depending on mouse genetic background, ethanol dose, and animal facility environment. This review focuses on these models and discusses these variations and some methods to improve the feeding protocol. The pathogenesis, clinical relevance, and translational studies of these models are also discussed.
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Affiliation(s)
- Bin Gao
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Ming-Jiang Xu
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Adeline Bertola
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- †Université Côte d’Azur, INSERM, Centre Méditerranéen de Médecine Moléculaire, Nice, France
| | - Hua Wang
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- ‡Department of Oncology, The First Affiliated Hospital, Institute for Liver Diseases of Anhui Medical University, Hefei, P.R. China
| | - Zhou Zhou
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Suthat Liangpunsakul
- §Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
- ¶Roudebush Veterans Administration Medical Center, Indianapolis, IN, USA
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Li Y, Ding WX. Adipose tissue autophagy and homeostasis in alcohol-induced liver injury. LIVER RESEARCH 2017; 1:54-62. [PMID: 29109891 PMCID: PMC5669268 DOI: 10.1016/j.livres.2017.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alcohol consumption leads to injury in multiple organs and systems, including the liver, brain, heart, skeletal muscle, pancreas, bone, immune system, and endocrine system. Emerging evidence indicates that alcohol also promotes adipose tissue dysfunction, which may contribute to injury progression in other organs and systems. Autophagy is a lysosomal degradation pathway that has been shown to regulate adipose tissue homeostasis and adipogenesis. Increasing evidence also demonstrates that alcohol consumption affects autophagy in multiple tissues. This review summarizes current knowledge regarding the effect of autophagy on adipose tissue and its potential roles in alcohol-induced adipose tissue atrophy as well as its contribution to alcohol-induced liver injury.
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Affiliation(s)
| | - Wen-Xing Ding
- Correspondence author. Wen-Xing Ding, Ph.D., Department of Pharmacology, Toxicology and Therapeutics; The University of Kansas Medical Center; Kansas City, KS USA.
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Kema VH, Khan I, Jamal R, Vishwakarma SK, Lakki Reddy C, Parwani K, Patel F, Patel D, Khan AA, Mandal P. Protective Effects of Diallyl Sulfide Against Ethanol-Induced Injury in Rat Adipose Tissue and Primary Human Adipocytes. Alcohol Clin Exp Res 2017; 41:1078-1092. [PMID: 28414868 DOI: 10.1111/acer.13398] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/06/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Alcohol consumption is the fourth leading cause of death and disability worldwide. Several cellular pathways contribute to alcohol-mediated tissue injury. Adipose tissue apart from functioning as an endocrine organ secretes several hormones and cytokines known as adipokines that are known to play a significant role in alcohol-induced tissue damage. This study was designed to test the efficacy of diallyl sulfide (DAS) in regulating the alcohol-induced outcomes on adipose tissue. METHODS Male Wistar rats were fed with 36% Lieber-DeCarli liquid diet containing ethanol (EtOH) for 4 weeks. Control rats were pair-fed with isocaloric diet containing maltodextrin instead of EtOH. During the last week of feeding protocol, the EtOH-fed rat group was given 200 mg/kg body weight of DAS through diet. We also studied DAS effect on isolated human primary adipocytes. Viability of human primary adipocytes on DAS treatment was assessed by MTT assay. Malondialdehyde (MDA), a marker of oxidative stress, was measured by HPLC and the thiobarbituric acid method. Expression of inflammatory genes and lipogenic genes was studied by qRT-PCR and Western blotting. Serum inflammatory gene expression was studied by ELISA. RESULTS Our study results showed that DAS could alleviate EtOH-induced expression levels of proinflammatory and endoplasmic reticulum (ER) stress genes and improve adipose tissue mass and adipocyte morphology in male Wistar rats fed Lieber-DeCarli diet containing 6% EtOH. Further, we showed that DAS reduced the expression of lipogenic genes and improved lipid accumulation and adipocyte mass in human primary adipocytes treated with EtOH. Subsequently, we also showed that oxidative stress, as measured by the changes in MDA levels, was reduced in both male Wistar rats and human primary adipocytes treated with EtOH plus DAS. CONCLUSIONS Our study results prove that DAS is effective in ameliorating EtOH-induced damage to adipose tissue as evidenced by the reduction brought about by DAS in oxidative stress, ER stress, and proinflammatory gene expression levels. DAS treatment also regulated lipogenic gene expression levels, thereby reducing free fatty acid release. In conclusion, this study has clinical implications with respect to alcohol-induced adipose tissue injury among alcohol users.
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Affiliation(s)
| | - Imran Khan
- Department of Biological Sciences , BITS Pilani, Hyderabad, India
| | - Reshma Jamal
- Department of Biological Sciences , BITS Pilani, Hyderabad, India
| | - Sandeep Kumar Vishwakarma
- Central Laboratory for Stem Cell Research & Translational Medicine , CLRD, Deccan College of Medical Sciences, Hyderabad, India
| | - Chandrakala Lakki Reddy
- Central Laboratory for Stem Cell Research & Translational Medicine , CLRD, Deccan College of Medical Sciences, Hyderabad, India
| | - Kirti Parwani
- Department of Biological Sciences , P D Patel Institute of Applied Sciences, Charotar University of Science and Technology, Anand, Gujarat, India
| | - Farhin Patel
- Department of Biological Sciences , P D Patel Institute of Applied Sciences, Charotar University of Science and Technology, Anand, Gujarat, India
| | - Dhara Patel
- Department of Biological Sciences , P D Patel Institute of Applied Sciences, Charotar University of Science and Technology, Anand, Gujarat, India
| | - Aleem A Khan
- Central Laboratory for Stem Cell Research & Translational Medicine , CLRD, Deccan College of Medical Sciences, Hyderabad, India
| | - Palash Mandal
- Department of Biological Sciences , BITS Pilani, Hyderabad, India.,Department of Biological Sciences , P D Patel Institute of Applied Sciences, Charotar University of Science and Technology, Anand, Gujarat, India
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Fibroblast Growth Factor 21 Deficiency Attenuates Experimental Colitis-Induced Adipose Tissue Lipolysis. Gastroenterol Res Pract 2017; 2017:3089378. [PMID: 28584524 PMCID: PMC5444037 DOI: 10.1155/2017/3089378] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/24/2017] [Accepted: 04/02/2017] [Indexed: 12/11/2022] Open
Abstract
Aims Nutrient deficiencies are common in patients with inflammatory bowel disease (IBD). Adipose tissue plays a critical role in regulating energy balance. Fibroblast growth factor 21 (FGF21) is an important endocrine metabolic regulator with emerging beneficial roles in lipid homeostasis. We investigated the impact of FGF21 in experimental colitis-induced epididymal white adipose tissue (eWAT) lipolysis. Methods Mice were given 2.5% dextran sulfate sodium (DSS) ad libitum for 7 days to induce colitis. The role of FGF21 was investigated using antibody neutralization or knockout (KO) mice. Lipolysis index and adipose lipolytic enzymes were determined. In addition, 3T3-L1 cells were pretreated with IL-6, followed by recombinant human FGF21 (rhFGF21) treatment; lipolysis was assessed. Results DSS markedly decreased eWAT/body weight ratio and increased serum concentrations of free fatty acid (FFA) and glycerol, indicating increased adipose tissue lipolysis. eWAT intracellular lipolytic enzyme expression/activation was significantly increased. These alterations were significantly attenuated in FGF21 KO mice and by circulating FGF21 neutralization. Moreover, DSS treatment markedly increased serum IL-6 and FGF21 levels. IL-6 pretreatment was necessary for the stimulatory effect of FGF21 on adipose lipolysis in 3T3-L1 cells. Conclusions Our results demonstrate that experimental colitis induces eWAT lipolysis via an IL-6/FGF21-mediated signaling pathway.
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Electrophysiological properties and augmented catecholamine release from chromaffin cells of WKY and SHR rats contributing to the hypertension development elicited by chronic EtOH consumption. Eur J Pharmacol 2017; 803:65-77. [DOI: 10.1016/j.ejphar.2017.03.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 03/07/2017] [Accepted: 03/13/2017] [Indexed: 12/12/2022]
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65
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Kharitonenkov A, DiMarchi R. Fibroblast growth factor 21 night watch: advances and uncertainties in the field. J Intern Med 2017; 281:233-246. [PMID: 27878865 DOI: 10.1111/joim.12580] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Fibroblast growth factor (FGF) 21 belongs to a hormone-like subgroup within the FGF superfamily. The members of this subfamily, FGF19, FGF21 and FGF23, are characterized by their reduced binding affinity for heparin that enables them to be transported in the circulation and function in an endocrine manner. It is likely that FGF21 also acts in an autocrine and paracrine fashion, as multiple organs can produce this protein and its plasma concentration seems to be below the level necessary to induce a pharmacological effect. FGF21 signals via FGF receptors, but for efficient receptor engagement it requires a cofactor, membrane-spanning βKlotho (KLB). The regulation of glucose uptake in adipocytes was the initial biological activity ascribed to FGF21, but this hormone is now recognized to stimulate many other pathways in vitro and display multiple pharmacological effects in metabolically compromised animals and humans. Understanding of the precise physiology of FGF21 and its potential medicinal role has evolved exponentially over the last decade, yet numerous aspects remain to be defined and others are a source of debate. Here we provide a historical overview of the advances in FGF21 biology focusing on the uncertainties in the mechanism of action as well as the differing viewpoints relating to this intriguing protein.
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Affiliation(s)
- A Kharitonenkov
- Department of Chemistry, Indiana University Bloomington, Bloomington, IN, USA
| | - R DiMarchi
- Department of Chemistry, Indiana University Bloomington, Bloomington, IN, USA
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66
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Steiner JL, Lang CH. Alcohol, Adipose Tissue and Lipid Dysregulation. Biomolecules 2017; 7:biom7010016. [PMID: 28212318 PMCID: PMC5372728 DOI: 10.3390/biom7010016] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 02/10/2017] [Indexed: 02/07/2023] Open
Abstract
Chronic alcohol consumption perturbs lipid metabolism as it increases adipose tissue lipolysis and leads to ectopic fat deposition within the liver and the development of alcoholic fatty liver disease. In addition to the recognition of the role of adipose tissue derived fatty acids in liver steatosis, alcohol also impacts other functions of adipose tissue and lipid metabolism. Lipid balance in response to long-term alcohol intake favors adipose tissue loss and fatty acid efflux as lipolysis is upregulated and lipogenesis is either slightly decreased or unchanged. Study of the lipolytic and lipogenic pathways has identified several regulatory proteins modulated by alcohol that contribute to these effects. Glucose tolerance of adipose tissue is also impaired by chronic alcohol due to decreased glucose transporter-4 availability at the membrane. As an endocrine organ, white adipose tissue (WAT) releases several adipokines that are negatively modulated following chronic alcohol consumption including adiponectin, leptin, and resistin. When these effects are combined with the enhanced expression of inflammatory mediators that are induced by chronic alcohol, a proinflammatory state develops within WAT, contributing to the observed lipodystrophy. Lastly, while chronic alcohol intake may enhance thermogenesis of brown adipose tissue (BAT), definitive mechanistic evidence is currently lacking. Overall, both WAT and BAT depots are impacted by chronic alcohol intake and the resulting lipodystrophy contributes to fat accumulation in peripheral organs, thereby enhancing the pathological state accompanying chronic alcohol use disorder.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA.
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA.
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Alund AW, Mercer KE, Pulliam CF, Suva LJ, Chen JR, Badger TM, Ronis MJJ. Partial Protection by Dietary Antioxidants Against Ethanol-Induced Osteopenia and Changes in Bone Morphology in Female Mice. Alcohol Clin Exp Res 2016; 41:46-56. [PMID: 27987315 DOI: 10.1111/acer.13284] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/02/2016] [Indexed: 12/16/2022]
Abstract
BACKGROUND Chronic alcohol consumption leads to increased fracture risk and an elevated risk of osteoporosis by decreasing bone accrual through increasing osteoclast activity and decreasing osteoblast activity. We have shown that this mechanism involves the generation of reactive oxygen species (ROS) produced by NADPH oxidases. It was hypothesized that different dietary antioxidants, N-acetyl cysteine (NAC; 1.2 mg/kg/d), and α-tocopherol (Vit.E; 60 mg/kg/d) would be able to attenuate the NADPH oxidase-mediated ROS effects on bone due to chronic alcohol intake. METHODS To study the effects of these antioxidants, female mice received a Lieber-DeCarli liquid diet containing ethanol (EtOH) with or without additional antioxidant for 8 weeks. RESULTS Tibias displayed decreased cortical bone mineral density in both the EtOH and EtOH + antioxidant groups compared to pair-fed (PF) and PF + antioxidant groups (p < 0.05). However, there was significant protection from trabecular bone loss in mice fed either antioxidant (p < 0.05). Microcomputed tomography analysis demonstrated a significant decrease in bone volume (bone volume/tissue volume) and trabecular number (p < 0.05), along with a significant increase in trabecular separation in the EtOH compared to PF (p < 0.05). In contrast, the EtOH + NAC and EtOH + Vit.E did not statistically differ from their respective PF controls. Ex vivo histologic sections of tibias were stained for nitrotyrosine, an indicator of intracellular damage by ROS, and tibias from mice fed EtOH exhibited significantly more staining than PF controls. EtOH treatment significantly increased the number of marrow adipocytes per mm as well as mRNA expression of aP2, an adipocyte marker in bone. Only NAC was able to reduce the number of marrow adipocytes to PF levels. EtOH-fed mice exhibited reduced bone length (p < 0.05) and had a reduced number of proliferating chondrocytes within the growth plate. NAC and Vit.E prevented this (p < 0.05). CONCLUSIONS These data show that alcohol's pathological effects on bone extend beyond decreasing bone mass and suggest a partial protective effect of the dietary antioxidants NAC and Vit.E at these doses with regard to alcohol effects on bone turnover and bone morphology.
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Affiliation(s)
- Alexander W Alund
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas.,Interdisciplinary Biomedical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Kelly E Mercer
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas.,Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Casey F Pulliam
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center New Orleans, New Orleans, Louisiana
| | - Larry J Suva
- Department of Orthopedic Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Jin-Ran Chen
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Thomas M Badger
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas.,Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Martin J J Ronis
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center New Orleans, New Orleans, Louisiana
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KLB is associated with alcohol drinking, and its gene product β-Klotho is necessary for FGF21 regulation of alcohol preference. Proc Natl Acad Sci U S A 2016; 113:14372-14377. [PMID: 27911795 DOI: 10.1073/pnas.1611243113] [Citation(s) in RCA: 164] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Excessive alcohol consumption is a major public health problem worldwide. Although drinking habits are known to be inherited, few genes have been identified that are robustly linked to alcohol drinking. We conducted a genome-wide association metaanalysis and replication study among >105,000 individuals of European ancestry and identified β-Klotho (KLB) as a locus associated with alcohol consumption (rs11940694; P = 9.2 × 10-12). β-Klotho is an obligate coreceptor for the hormone FGF21, which is secreted from the liver and implicated in macronutrient preference in humans. We show that brain-specific β-Klotho KO mice have an increased alcohol preference and that FGF21 inhibits alcohol drinking by acting on the brain. These data suggest that a liver-brain endocrine axis may play an important role in the regulation of alcohol drinking behavior and provide a unique pharmacologic target for reducing alcohol consumption.
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Abstract
PURPOSE OF REVIEW Acute pancreatitis is a major cause of gastrointestinal morbidity for which specific therapy is greatly needed to prevent progression to and induce resolution of severe disease. RECENT FINDINGS Innate immune components and metabolite signaling are recently identified as strong determinants of disease severity and resolution in acute pancreatitis and this work will be discussed herein. SUMMARY Targeting innate immune cell populations and metabolite signaling pathways in acute pancreatitis may result in broader and ultimately more efficacious re-direction of the inflammatory programme toward disease resolution and improved clinical outcomes.
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Souza-Smith FM, Lang CH, Nagy LE, Bailey SM, Parsons LH, Murray GJ. Physiological processes underlying organ injury in alcohol abuse. Am J Physiol Endocrinol Metab 2016; 311:E605-19. [PMID: 27436613 PMCID: PMC5142006 DOI: 10.1152/ajpendo.00270.2016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/11/2016] [Indexed: 02/07/2023]
Abstract
This review summarizes the American Physiological Society (APS) Presidential Symposium 1 entitled "Physiological Processes Underlying Organ Injury in Alcohol Abuse" at the 2016 Experimental Biology meeting. The symposium was organized by Dr. Patricia Molina, past president of the APS, was held on April 3 at the Convention Center in San Diego, CA, and was funded by the National Institute on Alcohol Abuse and Alcoholism. The "Physiological Processes Underlying Organ Injury in Alcohol Abuse Symposium" assembled experts and leaders in the field and served as a platform to discuss and share knowledge on the latest developments and scientific advances on the mechanisms underlying organ injury in alcohol abuse. This symposium provided unique, interdisciplinary alcohol research, including several organs, liver, muscle, adipose, and brain, affected by excessive alcohol use.
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Affiliation(s)
- Flavia M Souza-Smith
- Department of Physiology, Louisiana State University Health Science Center, New Orleans, Louisiana;
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Laura E Nagy
- Department of Pathobiology, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio
| | - Shannon M Bailey
- Department of Pathology, University of Alabama, Birmingham, Alabama
| | | | - Gary J Murray
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland
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Fibroblast growth factor 21 deficiency exacerbates chronic alcohol-induced hepatic steatosis and injury. Sci Rep 2016; 6:31026. [PMID: 27498701 PMCID: PMC4976373 DOI: 10.1038/srep31026] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 07/13/2016] [Indexed: 12/19/2022] Open
Abstract
Fibroblast growth factor 21 (FGF21) is a hepatokine that regulates glucose and lipid metabolism in the liver. We sought to determine the role of FGF21 in hepatic steatosis in mice exposed to chronic alcohol treatment and to discern underlying mechanisms. Male FGF21 knockout (FGF21 KO) and control (WT) mice were divided into groups that were fed either the Lieber DeCarli diet containing 5% alcohol or an isocaloric (control) diet for 4 weeks. One group of WT mice exposed to alcohol received recombinant human FGF21 (rhFGF21) in the last 5 days. Liver steatosis and inflammation were assessed. Primary mouse hepatocytes and AML-12 cells were incubated with metformin or rhFGF21. Hepatic genes and the products involved in in situ lipogenesis and fatty acid β-oxidation were analyzed. Alcohol exposure increased circulating levels and hepatic expression of FGF21. FGF21 depletion exacerbated alcohol-induced hepatic steatosis and liver injury, which was associated with increased activation of genes involved in lipogenesis mediated by SREBP1c and decreased expression of genes involved in fatty acid β-oxidation mediated by PGC1α. rhFGF21 administration reduced alcohol-induced hepatic steatosis and inflammation in WT mice. These results reveal that alcohol-induced FGF21 expression is a hepatic adaptive response to lipid dysregulation. Targeting FGF21 signaling could be a novel treatment approach for alcoholic steatohepatitis.
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Woolsey SJ, Beaton MD, Mansell SE, Leon-Ponte M, Yu J, Pin CL, Adams PC, Kim RB, Tirona RG. A Fibroblast Growth Factor 21-Pregnane X Receptor Pathway Downregulates Hepatic CYP3A4 in Nonalcoholic Fatty Liver Disease. Mol Pharmacol 2016; 90:437-46. [PMID: 27482056 DOI: 10.1124/mol.116.104687] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 07/28/2016] [Indexed: 12/28/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) alters drug response. We previously reported that NAFLD is associated with reduced in vivo CYP3A drug-metabolism activity and hepatic CYP3A4 expression in humans as well as mouse and human hepatoma models of the disease. Here, we investigated the role of the lipid- and glucose-modulating hormone fibroblast growth factor 21 (FGF21) in the molecular mechanism regulating CYP3A4 expression in NAFLD. In human subjects, mouse and cellular NAFLD models with lower CYP3A4 expression, circulating FGF21, or hepatic FGF21 mRNA levels were elevated. Administration of recombinant FGF21 or transient hepatic overexpression of FGF21 resulted in reduced liver CYP3A4 luciferase reporter activity in mice and decreased CYP3A4 mRNA expression and activity in cultured Huh7 hepatoma cells. Blocking canonical FGF21 signaling by pharmacological inhibition of MEK1 kinase in Huh7 cells caused de-repression of CYP3A4 mRNA expression with FGF21 treatment. Mice with high-fat diet-induced simple hepatic steatosis and lipid-loaded Huh7 cells had reduced nuclear localization of the pregnane X receptor (PXR), a key transcriptional regulator of CYP3A4 Furthermore, decreased nuclear PXR was observed in mouse liver and Huh7 cells after FGF21 treatment or FGF21 overexpression. Decreased PXR binding to the CYP3A4 proximal promoter was found in FGF21-treated Huh7 cells. An FGF21-PXR signaling pathway may be involved in decreased hepatic CYP3A4 metabolic activity in NAFLD.
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Affiliation(s)
- Sarah J Woolsey
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Melanie D Beaton
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Sara E Mansell
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Matilde Leon-Ponte
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Janice Yu
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Christopher L Pin
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Paul C Adams
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Richard B Kim
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Rommel G Tirona
- Department of Physiology and Pharmacology (S.J.W., J.Y., C.L.P., R.B.K., R.G.T), Division of Gastroenterology, Department of Medicine (M.D.B., P.C.A.), Division of Clinical Pharmacology, Department of Medicine (S.J.W., S.E.M., M.L.-P., J.Y., R.B.K., R.G.T.), Department of Paediatrics (C.L.P.), and Department of Oncology (C.L.P., R.B.K.), Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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Crowell KT, Steiner JL, Coleman CS, Lang CH. Decreased Whole-Body Fat Mass Produced by Chronic Alcohol Consumption is Associated with Activation of S6K1-Mediated Protein Synthesis and Increased Autophagy in Epididymal White Adipose Tissue. Alcohol Clin Exp Res 2016; 40:1832-45. [PMID: 27464336 DOI: 10.1111/acer.13159] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/23/2016] [Indexed: 12/25/2022]
Abstract
BACKGROUND Chronic alcohol consumption leads to a loss of white adipose tissue (WAT) but the underlying mechanisms for this lipodystrophy are not fully elucidated. This study tested the hypothesis that the reduction in WAT mass in chronic alcohol-fed mice is associated with a decreased protein synthesis specifically related to impaired function of mammalian target of rapamycin (mTOR). METHODS Adult male mice were provided an alcohol-containing liquid diet for 24 weeks or an isonitrogenous isocaloric control diet. In vivo protein synthesis was determined at this time and thereafter epididymal WAT (eWAT) was excised for analysis of signal transduction pathways central to controling protein synthesis and degradation. RESULTS While chronic alcohol feeding decreased whole-body and eWAT mass, this was associated with a discordant increase in protein synthesis in eWAT. This increase was not associated with a change in mTOR, 4E-BP1, Akt, or PRAS40 phosphorylation. Instead, a selective increase in phosphorylation of S6K1 and its downstream substrates, S6 and eIF4B was detected in alcohol-fed mice. Alcohol also increased eEF2K phosphorylation and decreased eEF2 phosphorylation consistent with increased translation elongation. Alcohol increased Atg12-5, LC3B-I and -II, and ULK1 S555 phosphorylation, suggesting increased autophagy, while markers of apoptosis (cleaved caspase-3 and -9, and PARP) were unchanged. Lipolytic enzymes (ATGL and HSL phosphorylation) were increased and lipogenic regulators (PPARγ and C/EBPα) were decreased in eWAT by alcohol. Although alcohol increased TNF-α, IL-6, and IL-1β mRNA, no change in key components of the NLRP3 inflammasome (NLRP3, ACS, and cleaved caspase-1) was detected suggesting alcohol did not increase pyroptosis. Plasma insulin did not differ between groups. CONCLUSIONS These results demonstrate that the alcohol-induced decrease in whole-body fat mass resulted in part from activation of autophagy in eWAT as protein synthesis was increased and mediated by the specific increase in the activity of S6K1.
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Affiliation(s)
- Kristen T Crowell
- Department of Cellular and Molecular Physiology, Penn State College Medicine, Hershey, Pennsylvania.,Department of Surgery, Penn State College Medicine, Hershey, Pennsylvania
| | - Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Penn State College Medicine, Hershey, Pennsylvania
| | - Catherine S Coleman
- Department of Cellular and Molecular Physiology, Penn State College Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College Medicine, Hershey, Pennsylvania.,Department of Surgery, Penn State College Medicine, Hershey, Pennsylvania
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Alund AW, Mercer KE, Suva LJ, Pulliam CF, Chen JR, Badger TM, Van Remmen H, Ronis MJJ. Reactive Oxygen Species Differentially Regulate Bone Turnover in an Age-Specific Manner in Catalase Transgenic Female Mice. J Pharmacol Exp Ther 2016; 358:50-60. [PMID: 27189961 DOI: 10.1124/jpet.116.233213] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/02/2016] [Indexed: 12/19/2022] Open
Abstract
Chronic ethyl alcohol (EtOH) consumption results in reactive oxygen species (ROS) generation in bone and osteopenia due to increased bone resorption and reduced bone formation. In this study, transgenic C57Bl/6J mice overexpressing human catalase (TgCAT) were used to test whether limiting excess hydrogen peroxide would protect against EtOH-mediated bone loss. Micro-computed tomography analysis of the skeletons of 6-week-old female chow-fed TgCAT mice revealed a high bone mass phenotype with increased cortical bone area and thickness as well as significantly increased trabecular bone volume (P < 0.05). Six-week-old wild-type (WT) and TgCAT female mice were chow fed or pair fed (PF) liquid diets with or without EtOH, approximately 30% of calories, for 8 weeks. Pair feeding of WT had no demonstrable effect on the skeleton; however, EtOH feeding of WT mice significantly reduced cortical and trabecular bone parameters along with bone strength compared with PF controls (P < 0.05). In contrast, EtOH feeding of TgCAT mice had no effect on trabecular bone compared with PF controls. At 14 weeks of age, there was significantly less trabecular bone and cortical cross-sectional area in TgCAT mice than WT mice (P < 0.05), suggesting impaired normal bone accrual with age. TgCAT mice expressed less collagen1α and higher sclerostin mRNA (P < 0.05), suggesting decreased bone formation in TgCAT mice. In conclusion, catalase overexpression resulted in greater bone mass than in WT mice at 6 weeks and lower bone mass at 14 weeks. EtOH feeding induced significant reductions in bone architecture and strength in WT mice, but TgCAT mice were partially protected. These data implicate ROS signaling in the regulation of bone turnover in an age-dependent manner, and indicate that excess hydrogen peroxide generation contributes to alcohol-induced osteopenia.
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Affiliation(s)
- Alexander W Alund
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Kelly E Mercer
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Larry J Suva
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Casey F Pulliam
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Jin-Ran Chen
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Thomas M Badger
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Holly Van Remmen
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
| | - Martin J J Ronis
- Arkansas Children's Nutrition Center (A.W.A., K.E.M., J.-R.C., T.M.B.), Interdisciplinary Biomedical Sciences (A.W.A.), Department of Pediatrics (K.E.M., J.-R.C., T.M.B.), and Department of Orthopedic Surgery (L.J.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, Louisiana (C.F.P., M.J.J.R.); and Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma (H.V.R.)
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Talukdar S, Owen BM, Song P, Hernandez G, Zhang Y, Zhou Y, Scott WT, Paratala B, Turner T, Smith A, Bernardo B, Müller CP, Tang H, Mangelsdorf DJ, Goodwin B, Kliewer SA. FGF21 Regulates Sweet and Alcohol Preference. Cell Metab 2016; 23:344-9. [PMID: 26724861 PMCID: PMC4749404 DOI: 10.1016/j.cmet.2015.12.008] [Citation(s) in RCA: 232] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 12/08/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is a hormone induced by various metabolic stresses, including ketogenic and high-carbohydrate diets, that regulates energy homeostasis. In humans, SNPs in and around the FGF21 gene have been associated with macronutrient preference, including carbohydrate, fat, and protein intake. Here we show that FGF21 administration markedly reduces sweet and alcohol preference in mice and sweet preference in cynomolgus monkeys. In mice, these effects require the FGF21 co-receptor β-Klotho in the central nervous system and correlate with reductions in dopamine concentrations in the nucleus accumbens. Since analogs of FGF21 are currently undergoing clinical evaluation for the treatment of obesity and type 2 diabetes, our findings raise the possibility that FGF21 administration could affect nutrient preference and other reward behaviors in humans.
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Affiliation(s)
- Saswata Talukdar
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Bryn M Owen
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Parkyong Song
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Genaro Hernandez
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yuan Zhang
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yingjiang Zhou
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - William T Scott
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Bhavna Paratala
- Drug Safety Research and Development, Pfizer Worldwide Research and Development, Groton, CT 06340, USA
| | - Tod Turner
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Andrew Smith
- Drug Safety Research and Development, Pfizer Worldwide Research and Development, Groton, CT 06340, USA
| | - Barbara Bernardo
- Drug Safety Research and Development, Pfizer Worldwide Research and Development, Groton, CT 06340, USA
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany; MRC Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Hao Tang
- Department of Clinical Science, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - David J Mangelsdorf
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Bryan Goodwin
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Steven A Kliewer
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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