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Chen M, Zhu J, Luo H, Mu W, Guo L. The journey towards physiology and pathology: Tracing the path of neuregulin 4. Genes Dis 2024; 11:687-700. [PMID: 37692526 PMCID: PMC10491916 DOI: 10.1016/j.gendis.2023.03.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 02/11/2023] [Accepted: 03/05/2023] [Indexed: 09/12/2023] Open
Abstract
Neuregulin 4 (Nrg4), an epidermal growth factor (EGF) family member, can bind to and activate the ErbB4 receptor tyrosine kinase. Nrg4 has five different isoforms by alternative splicing and performs a wide variety of functions. Nrg4 is involved in a spectrum of physiological processes including neurobiogenesis, lipid metabolism, glucose metabolism, thermogenesis, and angiogenesis. In pathological processes, Nrg4 inhibits inflammatory factor levels and suppresses apoptosis in inflammatory diseases. In addition, Nrg4 could ameliorate obesity, insulin resistance, and cardiovascular diseases. Furthermore, Nrg4 improves non-alcoholic fatty liver disease (NAFLD) by promoting autophagy, improving lipid metabolism, and inhibiting cell death of hepatocytes. Besides, Nrg4 is closely related to the development of cancer, hyperthyroidism, and some other diseases. Therefore, elucidation of the functional role and mechanisms of Nrg4 will provide a clearer view of the therapeutic potential and possible risks of Nrg4.
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Affiliation(s)
- Min Chen
- School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China
| | - Jieying Zhu
- School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China
| | - Hongyang Luo
- School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China
| | - Wangjing Mu
- School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China
| | - Liang Guo
- School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China
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Abbasi K, Zarezadeh R, Valizadeh A, Mehdizadeh A, Hamishehkar H, Nouri M, Darabi M. White-brown adipose tissue interplay in polycystic ovary syndrome: Therapeutic avenues. Biochem Pharmacol 2024; 220:116012. [PMID: 38159686 DOI: 10.1016/j.bcp.2023.116012] [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: 11/28/2023] [Accepted: 12/22/2023] [Indexed: 01/03/2024]
Abstract
This study highlights the therapeutic potential of activating brown adipose tissue (BAT) for managing polycystic ovary syndrome (PCOS), a prevalent endocrine disorder associated with metabolic and reproductive abnormalities. BAT plays a crucial role in regulating energy expenditure and systemic insulin sensitivity, making it an attractive target for the treatment of obesity and metabolic diseases. Recent research suggests that impaired BAT function and mass may contribute to the link between metabolic disturbances and reproductive issues in PCOS. Additionally, abnormal white adipose tissue (WAT) can exacerbate these conditions by releasing adipokines and nonesterified fatty acids. In this review, we explored the impact of WAT changes on BAT function in PCOS and discussed the potential of BAT activation as a therapeutic strategy to improve PCOS symptoms. We propose that BAT activation holds promise for managing PCOS; however, further research is needed to confirm its efficacy and to develop clinically feasible methods for BAT activation.
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Affiliation(s)
- Khadijeh Abbasi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Zarezadeh
- Women's Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Valizadeh
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Mehdizadeh
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamed Hamishehkar
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Nouri
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Masoud Darabi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; Division of Experimental Oncology, Department of Hematology and Oncology, University Medical Center Schleswig-Holstein, Campus Lübeck, Germany.
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3
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Ziqubu K, Dludla PV, Mabhida SE, Jack BU, Keipert S, Jastroch M, Mazibuko-Mbeje SE. Brown adipose tissue-derived metabolites and their role in regulating metabolism. Metabolism 2024; 150:155709. [PMID: 37866810 DOI: 10.1016/j.metabol.2023.155709] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 09/28/2023] [Accepted: 10/14/2023] [Indexed: 10/24/2023]
Abstract
The discovery and rejuvenation of metabolically active brown adipose tissue (BAT) in adult humans have offered a new approach to treat obesity and metabolic diseases. Beyond its accomplished role in adaptive thermogenesis, BAT secretes signaling molecules known as "batokines", which are instrumental in regulating whole-body metabolism via autocrine, paracrine, and endocrine action. In addition to the intrinsic BAT metabolite-oxidizing activity, the endocrine functions of these molecules may help to explain the association between BAT activity and a healthy systemic metabolic profile. Herein, we review the evidence that underscores the significance of BAT-derived metabolites, especially highlighting their role in controlling physiological and metabolic processes involving thermogenesis, substrate metabolism, and other essential biological processes. The conversation extends to their capacity to enhance energy expenditure and mitigate features of obesity and its related metabolic complications. Thus, metabolites derived from BAT may provide new avenues for the discovery of metabolic health-promoting drugs with far-reaching impacts. This review aims to dissect the complexities of the secretory role of BAT in modulating local and systemic metabolism in metabolic health and disease.
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Affiliation(s)
- Khanyisani Ziqubu
- Department of Biochemistry, North-West University, Mmabatho 2745, South Africa
| | - Phiwayinkosi V Dludla
- Cochrane South Africa, South African Medical Research Council, Tygerberg 7505, South Africa; Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa
| | - Sihle E Mabhida
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Babalwa U Jack
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Susanne Keipert
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Martin Jastroch
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
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Taheri F, Hosseinzadeh-Attar MJ, Alipoor E, Honarkar-Shafie E, Yaseri M, Vasheghani-Farahani A. Implications of the Serum Concentrations of Neuregulin-4 (Nrg4) in Patients with Coronary Artery Disease: A Case-Control Study. J Tehran Heart Cent 2023; 18:170-176. [PMID: 38146414 PMCID: PMC10748655 DOI: 10.18502/jthc.v18i3.14111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 06/15/2023] [Indexed: 12/27/2023] Open
Abstract
Background Neuregulin-4 (Nrg4), a novel brown fat-enriched factor, has been reported to play a crucial role in developing metabolic disorders. The current case-control study aimed to investigate the association between serum Nrg4 and coronary artery disease (CAD). Methods This study enrolled 43 patients with CAD and 43 subjects with normal coronary arteries diagnosed by coronary angiography. Anthropometric and biochemical parameters were measured and recorded. The serum Nrg4 level was determined using the enzyme-linked immunosorbent assay. The relationships between circulating Nrg4 and CAD and other clinical parameters were analyzed. A receiver operating characteristic analysis was applied to assess the utility of Nrg4 in identifying CAD. Results The study population comprised 86 patients, including 64 men (74.4%), at a mean age of 57.83±6.01 years. Patients with CAD had significantly lower serum Nrg4 than the control group (P<0.001). The serum Nrg4 level was negatively correlated with anthropometric variables, including the body mass index, waist circumference, and the waist-to-hip ratio, fasting blood glucose, and the triglyceride-glucose index (P<0.05). In multivariable-adjusted regression analysis, the odds of CAD decreased by 46% per 1 SD elevation in the serum Nrg4 level (OR, 0.54; 95% CI, 0.40 to 0.73; P<0.001) after controlling for potential confounders. Nrg4 showed a significantly high area under the curve value (AUC, 0.85; 95% CI, 0.75 to 0.94) with 81.4% sensitivity and 95.3% specificity to identify CAD. Conclusion Generally, the serum level of Nrg4 declines in patients with CAD, which might be an independent risk factor for CAD.
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Affiliation(s)
- Fatemeh Taheri
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Elham Alipoor
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
- Cardiac Primary Prevention Research Center, Cardiovascular Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Elaheh Honarkar-Shafie
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Yaseri
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Vasheghani-Farahani
- Cardiac Primary Prevention Research Center, Cardiovascular Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran
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Kwon I, Talib NF, Zhu J, Yang HI, Kim KS. Effects of aging-induced obesity on the transcriptional expression of adipogenesis and thermogenic activity in the gonadal white adipose, brown adipose, and skeletal muscle tissues. Phys Act Nutr 2023; 27:39-49. [PMID: 37583071 PMCID: PMC10440178 DOI: 10.20463/pan.2023.0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 08/17/2023] Open
Abstract
PURPOSE Aging is closely associated with chronic metabolic diseases, such as obesity, which lead to increased adiposity, skeletal muscle wasting, and imbalanced cellular energy metabolism. However, transcriptional profiles representing energy imbalances in aging-induced obesity are not fully understood. Thus, this study aimed to investigate the candidate genes predominantly regulated in aging-related obesity in spontaneously aged mice. METHODS Male C57BL/6J mice were divided into three age groups according to age: 2- (young), 12- (middle-aged), and 24- (old) months. Body weight and body composition parameters were measured in all mice. Gonadal white adipose tissue (gWAT), brown adipose tissue (BAT), and skeletal muscle (SM) were dissected and weighed. The target tissues were assessed using biochemical and histological assays. RESULTS Aging-induced obesity increased adipose mass and decreased SM weight through processes of adipocyte hypertrophy; however, recruitment of modulating adipogenesis-inducing transcription factors did not occur. Among adipokines, leptin level was greatly increased in the gWAT during aging. Interestingly, the β2-adrenergic receptor had a higher affinity than the β3-adrenergic receptor in aging-induced obesity. For the thermogenic regulation through β-adrenergic receptors (β-ARs), a declined uncoupling protein-1 (UCP-1) in the BAT was relevant to aging-induced obesity. CONCLUSION Aging-induced obesity increases leptin levels in adipocytes and decreases UCP-1 in BAT through β-ARs, according to transcriptional gene profiling. WAT browning increases energy expenditure due to exercise training adaptations. Further research is needed to discover more effective methods, such as exercise, against aging-induced obesity.
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Affiliation(s)
- Insu Kwon
- Department of Clinical Pharmacology and Therapeutics, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Nurul Fatihah Talib
- Department of Biomedical Science, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - JunShu Zhu
- Department of Biomedical Science, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Hyung-In Yang
- Division of Rheumatology, Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea
| | - Kyoung Soo Kim
- Department of Clinical Pharmacology and Therapeutics, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
- Department of Biomedical Science, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
- East-West Bone & Joint Disease Research Institute, Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea
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Zhang Y, Zhu Y, Wang J, Jin L, Guo M, Chen L, Zhang L, Li Y, Wan B, Zhang R, Jia W, Hu C. Neuregulin4 Acts on Hypothalamic ErBb4 to Excite Oxytocin Neurons and Preserve Metabolic Homeostasis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2204824. [PMID: 37060105 DOI: 10.1002/advs.202204824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 03/10/2023] [Indexed: 06/04/2023]
Abstract
Neuregulin 4 (Nrg4) is an adipose tissue-enriched secreted factor that modulates glucose and lipid metabolism. Nrg4 is closely associated with obesity and preserves diet-induced metabolic disorders. However, the specific mechanisms via which Nrg4 regulates metabolic homeostasis remain incompletely understood. Here, this work finds that the Nrg4 receptor, ErbB4, is highly expressed in the hypothalamus, and the phosphorylation of hypothalamic ErbB4 is reduced in diet-induced obesity (DIO) mice. Peripheral Nrg4 can act on ErbB4 via blood circulation and excite neurons in the paraventricular nucleus of hypothalamus (PVN). Central administration of recombinant Nrg4 protein (rNrg4) reduces obesity and related metabolic disorders by influencing energy expenditure and intake. Overexpression of ErbB4 in the PVN protects against obesity, whereas its knock down in oxytocin (Oxt) neuron accelerates obesity. Furthermore, Nrg4-ErbB4 signaling excites Oxt release, and ablation of Oxt neuron considerably attenuates the effect of Nrg4 on energy balance. These data suggest that the hypothalamus is a key target of Nrg4, which partially explains the multifaceted roles of Nrg4 in metabolism.
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Affiliation(s)
- Yi Zhang
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Yangyang Zhu
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
- Institute for Metabolic Disease, Fengxian Central Hospital Affiliated to Southern Medical University, Shanghai, 201449, P. R. China
| | - Jinghui Wang
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
- Department of Endocrinology, Affiliated Hospital of Nantong University, Nantong, 226001, P. R. China
| | - Li Jin
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Mingwei Guo
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, P. R. China
| | - Liwei Chen
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Lina Zhang
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Yangyang Li
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Baocheng Wan
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Rong Zhang
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Weiping Jia
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
| | - Cheng Hu
- Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Centre for Diabetes, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, P. R. China
- Institute for Metabolic Disease, Fengxian Central Hospital Affiliated to Southern Medical University, Shanghai, 201449, P. R. China
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Kreissl FK, Banki MA, Droujinine IA. Molecular methods to study protein trafficking between organs. Proteomics 2023; 23:e2100331. [PMID: 36478633 DOI: 10.1002/pmic.202100331] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022]
Abstract
Interorgan communication networks are key regulators of organismal homeostasis, and their dysregulation is associated with a variety of pathologies. While mass spectrometry proteomics identifies circulating proteins and can correlate their abundance with disease phenotypes, the tissues of origin and destinations of these secreted proteins remain largely unknown. In vitro approaches to study protein secretion are valuable, however, they may not mimic the complexity of in vivo environments. More recently, the development of engineered promiscuous BirA* biotin ligase derivatives has enabled tissue-specific tagging of cellular secreted proteomes in vivo. The use of biotin as a molecular tag provides information on the tissue of origin and destination, and enables the enrichment of low-abundance hormone proteins. Therefore, promiscuous protein biotinylation is a valuable tool to study protein secretion in vivo.
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Affiliation(s)
- Felix K Kreissl
- Department of Immunology and Microbiology, Scripps Research, La Jolla, California, USA
| | - Michael A Banki
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
| | - Ilia A Droujinine
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
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Liu Y, Chen M. Neuregulin 4 as a novel adipokine in energy metabolism. Front Physiol 2023; 13:1106380. [PMID: 36703934 PMCID: PMC9873244 DOI: 10.3389/fphys.2022.1106380] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/30/2022] [Indexed: 01/11/2023] Open
Abstract
Adipose tissue has been shown to play a key role in energy metabolism and it has been shown to regulate metabolic homeostasis through the secretion of adipokines. Neuregulin 4 (Nrg4), a novel adipokine secreted mainly by brown adipose tissue (BAT), has recently been characterized as having an important effect on the regulation of energy homeostasis and glucolipid metabolism. Nrg4 can modulate BAT-related thermogenesis by increasing sympathetic innervation of adipose tissue and therefore has potential metabolic benefits. Nrg4 improves metabolic dysregulation in various metabolic diseases such as insulin resistance, obesity, non-alcoholic fatty liver disease, and diabetes through several mechanisms such as anti-inflammation, autophagy regulation, pro-angiogenesis, and lipid metabolism normalization. However, inconsistent findings are found regarding the effects of Nrg4 on metabolic diseases in clinical settings, and this heterogeneity needs to be further clarified by future studies. The potential metabolic protective effect of Nrg4 suggests that it may be a promising endocrine therapeutic target.
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Shi L, Li Y, Xu X, Cheng Y, Meng B, Xu J, Xiang L, Zhang J, He K, Tong J, Zhang J, Xiang L, Xiang G. Brown adipose tissue-derived Nrg4 alleviates endothelial inflammation and atherosclerosis in male mice. Nat Metab 2022; 4:1573-1590. [PMID: 36400933 PMCID: PMC9684073 DOI: 10.1038/s42255-022-00671-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 09/30/2022] [Indexed: 11/21/2022]
Abstract
Brown adipose tissue (BAT) activity contributes to cardiovascular health by its energy-dissipating capacity but how BAT modulates vascular function and atherosclerosis through endocrine mechanisms remains poorly understood. Here we show that BAT-derived neuregulin-4 (Nrg4) ameliorates atherosclerosis in mice. BAT-specific Nrg4 deficiency accelerates vascular inflammation and adhesion responses, endothelial dysfunction and apoptosis and atherosclerosis in male mice. BAT-specific Nrg4 restoration alleviates vascular inflammation and adhesion responses, attenuates leukocyte homing and reduces endothelial injury and atherosclerosis in male mice. In endothelial cells, Nrg4 decreases apoptosis, inflammation and adhesion responses induced by oxidized low-density lipoprotein. Mechanistically, protein kinase B (Akt)-nuclear factor-κB signaling is involved in the beneficial effects of Nrg4 on the endothelium. Taken together, the results reveal Nrg4 as a potential cross-talk factor between BAT and arteries that may serve as a target for atherosclerosis.
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Affiliation(s)
- Lingfeng Shi
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
- Endocrinology Department, The First Affiliated Hospital of the Army Medical University (Third Military Medical University), Chongqing, China
| | - Yixiang Li
- Department of Hematology and Medical Oncology, School of Medicine, Emory University, Atlanta, GA, USA
| | - Xiaoli Xu
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
| | - Yangyang Cheng
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
| | - Biying Meng
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
| | - Jinling Xu
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Lin Xiang
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
| | - Jiajia Zhang
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China
| | - Kaiyue He
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Jiayue Tong
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Junxia Zhang
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China.
| | - Lingwei Xiang
- Centers for Surgery and Public Health, Brigham and Women's Hospital, Boston, MA, USA.
| | - Guangda Xiang
- Department of Endocrinology, General Hospital of Central Theater Command, Wuhan, China.
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China.
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Scheel AK, Espelage L, Chadt A. Many Ways to Rome: Exercise, Cold Exposure and Diet-Do They All Affect BAT Activation and WAT Browning in the Same Manner? Int J Mol Sci 2022; 23:ijms23094759. [PMID: 35563150 PMCID: PMC9103087 DOI: 10.3390/ijms23094759] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/19/2022] [Accepted: 04/22/2022] [Indexed: 02/08/2023] Open
Abstract
The discovery of functional brown adipose tissue (BAT) in adult humans and the possibility to recruit beige cells with high thermogenic potential within white adipose tissue (WAT) depots opened the field for new strategies to combat obesity and its associated comorbidities. Exercise training as well as cold exposure and dietary components are associated with the enhanced accumulation of metabolically-active beige adipocytes and BAT activation. Both activated beige and brown adipocytes increase their metabolic rate by utilizing lipids to generate heat via non-shivering thermogenesis, which is dependent on uncoupling protein 1 (UCP1) in the inner mitochondrial membrane. Non-shivering thermogenesis elevates energy expenditure and promotes a negative energy balance, which may ameliorate metabolic complications of obesity and Type 2 Diabetes Mellitus (T2DM) such as insulin resistance (IR) in skeletal muscle and adipose tissue. Despite the recent advances in pharmacological approaches to reduce obesity and IR by inducing non-shivering thermogenesis in BAT and WAT, the administered pharmacological compounds are often associated with unwanted side effects. Therefore, lifestyle interventions such as exercise, cold exposure, and/or specified dietary regimens present promising anchor points for future disease prevention and treatment of obesity and T2DM. The exact mechanisms where exercise, cold exposure, dietary interventions, and pharmacological treatments converge or rather diverge in their specific impact on BAT activation or WAT browning are difficult to determine. In the past, many reviews have demonstrated the mechanistic principles of exercise- and/or cold-induced BAT activation and WAT browning. In this review, we aim to summarize not only the current state of knowledge on the various mechanistic principles of diverse external stimuli on BAT activation and WAT browning, but also present their translational potential in future clinical applications.
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Affiliation(s)
- Anna K. Scheel
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz-Center for Diabetes Research at the Heinrich Heine University, Medical Faculty, Düsseldorf, Auf’m Hennekamp 65, 40225 Duesseldorf, Germany; (A.K.S.); (L.E.)
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, 85764 München, Germany
| | - Lena Espelage
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz-Center for Diabetes Research at the Heinrich Heine University, Medical Faculty, Düsseldorf, Auf’m Hennekamp 65, 40225 Duesseldorf, Germany; (A.K.S.); (L.E.)
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, 85764 München, Germany
| | - Alexandra Chadt
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz-Center for Diabetes Research at the Heinrich Heine University, Medical Faculty, Düsseldorf, Auf’m Hennekamp 65, 40225 Duesseldorf, Germany; (A.K.S.); (L.E.)
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, 85764 München, Germany
- Correspondence: ; Tel./Fax: +49-211-3382-577/430
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11
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Gavaldà-Navarro A, Villarroya J, Cereijo R, Giralt M, Villarroya F. The endocrine role of brown adipose tissue: An update on actors and actions. Rev Endocr Metab Disord 2022; 23:31-41. [PMID: 33712997 DOI: 10.1007/s11154-021-09640-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/26/2021] [Indexed: 02/06/2023]
Abstract
In recent years, brown adipose tissue (BAT) has been recognized not only as a main site of non-shivering thermogenesis in mammals, but also as an endocrine organ. BAT secretes a myriad of regulatory factors. These so-called batokines exert local autocrine and paracrine effects, as well as endocrine actions targeting tissues and organs at a distance. The endocrine batokines include peptide factors, such as fibroblast growth factor-21 (FGF21), neuregulin-4 (NRG4), phospholipid transfer protein (PLTP), interleukin-6, adiponectin and myostatin, and also lipids (lipokines; e.g., 12,13-dihydroxy-9Z-octadecenoic acid [12,13-diHOME]) and miRNAs (e.g., miR-99b). The liver, heart, and skeletal muscle are the most commonly reported targets of batokines. In response to BAT thermogenic activation, batokines such as NRG4 and PLTP are released and act to reduce hepatic steatosis and improve insulin sensitivity. Stress-induced interleukin-6-mediated signaling from BAT to liver favors hepatic glucose production through enhanced gluconeogenesis. Batokines may act on liver to induce the secretion of regulatory hepatokines (e.g. FGF21 and bile acids in response to miR-99b and PLTP, respectively), thereby resulting in a systemic expansion of BAT-originating signals. Batokines also target extrahepatic tissues: FGF21 and 12,13-diHOME are cardioprotective, whereas BAT-secreted myostatin and 12,13-diHOME influence skeletal muscle development and performance. Further research is needed to ascertain in humans the role of batokines, which have been identified mostly in experimental models. The endocrine role of BAT may explain the association between active BAT and a healthy metabolism in the human system, which is characterized by small amounts of BAT and a likely moderate BAT-mediated energy expenditure.
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Affiliation(s)
- Aleix Gavaldà-Navarro
- Departament de Bioquimica I Biomedicina Molecular, and Institut de Biomedicina de La Universitat de Barcelona, Barcelona, Catalonia, Spain
- Institut de Recerca Sant Joan de Déu, Esplugues, Catalonia, Spain
- CIBER Fisiopatología de La Obesidad Y Nutrición, Madrid, Spain
| | - Joan Villarroya
- Departament de Bioquimica I Biomedicina Molecular, and Institut de Biomedicina de La Universitat de Barcelona, Barcelona, Catalonia, Spain
- Institut de Recerca Sant Joan de Déu, Esplugues, Catalonia, Spain
- CIBER Fisiopatología de La Obesidad Y Nutrición, Madrid, Spain
| | - Rubén Cereijo
- Departament de Bioquimica I Biomedicina Molecular, and Institut de Biomedicina de La Universitat de Barcelona, Barcelona, Catalonia, Spain
- CIBER Fisiopatología de La Obesidad Y Nutrición, Madrid, Spain
- Institut de Recerca Hospital de La Santa Creu I Sant Pau, Barcelona, Spain
| | - Marta Giralt
- Departament de Bioquimica I Biomedicina Molecular, and Institut de Biomedicina de La Universitat de Barcelona, Barcelona, Catalonia, Spain
- Institut de Recerca Sant Joan de Déu, Esplugues, Catalonia, Spain
- CIBER Fisiopatología de La Obesidad Y Nutrición, Madrid, Spain
| | - Francesc Villarroya
- Departament de Bioquimica I Biomedicina Molecular, and Institut de Biomedicina de La Universitat de Barcelona, Barcelona, Catalonia, Spain.
- Institut de Recerca Sant Joan de Déu, Esplugues, Catalonia, Spain.
- CIBER Fisiopatología de La Obesidad Y Nutrición, Madrid, Spain.
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Role of Distinct Fat Depots in Metabolic Regulation and Pathological Implications. Rev Physiol Biochem Pharmacol 2022; 186:135-176. [PMID: 35915363 DOI: 10.1007/112_2022_73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
People suffering from obesity and associated metabolic disorders including diabetes are increasing exponentially around the world. Adipose tissue (AT) distribution and alteration in their biochemical properties play a major role in the pathogenesis of these diseases. Emerging evidence suggests that AT heterogeneity and depot-specific physiological changes are vital in the development of insulin resistance in peripheral tissues like muscle and liver. Classically, AT depots are classified into white adipose tissue (WAT) and brown adipose tissue (BAT); WAT is the site of fatty acid storage, while BAT is a dedicated organ of metabolic heat production. The discovery of beige adipocyte clusters in WAT depots indicates AT heterogeneity has a more central role than hither to ascribed. Therefore, we have discussed in detail the current state of understanding on cellular and molecular origin of different AT depots and their relevance toward physiological metabolic homeostasis. A major focus is to highlight the correlation between altered WAT distribution in the body and metabolic pathogenesis in animal models and humans. We have also underscored the disparity in the molecular (including signaling) changes in various WAT tissues during diabetic pathogenesis. Exercise-mediated beneficial alteration in WAT physiology/distribution that protects against metabolic disorders is evolving. Here we have discussed the depot-specific biochemical adjustments induced by different forms of exercise. A detailed understanding of the molecular details of inter-organ crosstalk via substrate utilization/storage and signaling through chemokines provide strategies to target selected WAT depots to pharmacologically mimic the benefits of exercise countering metabolic diseases including diabetes.
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Pinckard KM, Stanford KI. The Heartwarming Effect of Brown Adipose Tissue. Mol Pharmacol 2021; 102:460-471. [PMID: 34933905 PMCID: PMC9341250 DOI: 10.1124/molpharm.121.000328] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/27/2021] [Indexed: 11/22/2022] Open
Abstract
Brown adipose tissue (BAT) is a metabolically active tissue that improves glucose metabolism and protects against the development of type 2 diabetes and obesity. However, the role of BAT to improve cardiovascular health has only recently been investigated. In this review, we discuss multiple mechanisms through which both the thermogenic and endocrine functions of BAT mediate cardiac health. β-adrenergic stimulation activates the thermogenic function of BAT, resulting in reduced circulating lipids and glucose, and enhanced clearance of hepatic cholesterol-enriched remnants leading to reduced atherosclerotic region size. Additionally, the thermogenic role of BAT has been implicated in activation of the protein kinase B-extracellular-signal-regulated kinase (ERK) 1/2 pathway after myocardial infarction (MI), contributing to reduced injury size. The endocrine function of BAT has also been implicated to improve both systemic metabolic health and cardiac health. Specifically, the batokines fibroblast growth factor 21 (FGF21) and 12,13-diHOME improve cardiovascular health via reduced hypertension, hypertrophy and MI injury size (FGF21) or by directly improving cardiac function via calcium cycling (12,13-diHOME). Finally, we discuss relevant pharmacological treatment methods currently aiming to activate BAT, typically through sympathetic activation.
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Steinhoff KG, Krause K, Linder N, Rullmann M, Volke L, Gebhardt C, Busse H, Stumvoll M, Blüher M, Sabri O, Hesse S, Tönjes A. Effects of Hyperthyroidism on Adipose Tissue Activity and Distribution in Adults. Thyroid 2021; 31:519-527. [PMID: 33019884 DOI: 10.1089/thy.2019.0806] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background: Positron emission tomography (PET) has provided evidence that adult humans retain metabolically active brown adipose tissue (BAT) depots. Thyroid hormones (TH) stimulate BAT thermogenesis by central and peripheral mechanisms. However, the effect of hyperthyroidism on BAT activity and BAT volume in humans is yet not fully understood. The aim of this study was to investigate the effect of TH on (i) the metabolic activity of brown and white adipose tissue (WAT) depots, (ii) on abdominal visceral and subcutaneous adipose tissue area, and (iii) on serum levels of metabolically active cytokines. Methods: Nineteen patients with overt hyperthyroidism were investigated through repeated 2-[18F]fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (2-[18F]FDG PET/CT) in the hyperthyroid and in the euthyroid state. The 2-[18F]FDG uptake was calculated as standard uptake ratio with blood pool as reference. Fat areas were quantified by means of CT segmentation. Serum levels of fetuin A and B, fibroblast growth factor 21, adipocyte fatty acid-binding protein (AFABP), retinol-binding protein 4, pro-enkephalin, pro-neurotensin, and neuregulin 4 were determined in the hyperthyroid and in the euthyroid state for each subject. Results: 2-[18F]FDG uptake was increased in the hyperthyroid state in BAT in comparison with the euthyroid phase (p = 0.001). There was no correlation between serum free triiodothyronine (fT3) and free thyroxine (fT4) levels and 2-[18F]FDG uptake in BAT or WAT. In the hyperthyroid state, fT3 levels were positively associated with skeletal muscle standardized uptake value ratios. Areas of visceral adipose tissue and skeletal muscle were significantly decreased in hyperthyroidism. AFABP levels correlated positively with fT3 (p = 0.031, β = 0.28) and fT4 (p = 0.037, β = 0.27) in the hyperthyroid state. Conclusions: Our results suggest that the contribution of increased TH levels to the glucose uptake of BAT and WAT is low compared with that of the skeletal muscle. Hyperthyroid subjects have reduced areas of visceral adipose tissue and increased AFABP levels.
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Affiliation(s)
| | - Kerstin Krause
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
| | - Nicolas Linder
- Department of Radiology; University of Leipzig Medical Center, Leipzig, Germany
- Integrated Research and Treatment Center (IFB) Adiposity Diseases Leipzig, Leipzig, Germany
| | - Michael Rullmann
- Department of Nuclear Medicine; Leipzig, Germany
- Integrated Research and Treatment Center (IFB) Adiposity Diseases Leipzig, Leipzig, Germany
| | - Lisa Volke
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
| | - Claudia Gebhardt
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
- Helmholtz Zentrum München, Helmholtz Institute for Metabolic, Obesity and Vascular Research, Leipzig, Germany
| | - Harald Busse
- Department of Radiology; University of Leipzig Medical Center, Leipzig, Germany
| | - Michael Stumvoll
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
- Integrated Research and Treatment Center (IFB) Adiposity Diseases Leipzig, Leipzig, Germany
- Helmholtz Zentrum München, Helmholtz Institute for Metabolic, Obesity and Vascular Research, Leipzig, Germany
| | - Matthias Blüher
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
- Integrated Research and Treatment Center (IFB) Adiposity Diseases Leipzig, Leipzig, Germany
- Helmholtz Zentrum München, Helmholtz Institute for Metabolic, Obesity and Vascular Research, Leipzig, Germany
| | - Osama Sabri
- Department of Nuclear Medicine; Leipzig, Germany
| | - Swen Hesse
- Department of Nuclear Medicine; Leipzig, Germany
- Integrated Research and Treatment Center (IFB) Adiposity Diseases Leipzig, Leipzig, Germany
| | - Anke Tönjes
- Medical Department III-Endocrinology, Nephrology, Rheumatology; Leipzig, Germany
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Ahmad B, Vohra MS, Saleemi MA, Serpell CJ, Fong IL, Wong EH. Brown/Beige adipose tissues and the emerging role of their secretory factors in improving metabolic health: The batokines. Biochimie 2021; 184:26-39. [PMID: 33548390 DOI: 10.1016/j.biochi.2021.01.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/22/2020] [Accepted: 01/28/2021] [Indexed: 12/12/2022]
Abstract
Brown and beige adipose tissues are the primary sites for adaptive non-shivering thermogenesis. Although they have been known principally for their thermogenic effects, in recent years, it has emerged that, just like white adipose tissue (WAT), brown and beige adipose tissues also play an important role in the regulation of metabolic health through secretion of various brown adipokines (batokines) in response to various physiological cues. These secreted batokines target distant organs and tissues such as the liver, heart, skeletal muscles, brain, WAT, and perform various local and systemic functions in an autocrine, paracrine, or endocrine manner. Brown and beige adipose tissues are therefore now receiving increasing levels of attention with respect to their effects on various other organs and tissues. Identification of novel secreted factors by these tissues may help in the discovery of drug candidates for the treatment of various metabolic disorders such as obesity, type-2 diabetes, skeletal deformities, cardiovascular diseases, dyslipidemia. In this review, we comprehensively describe the emerging secretory role of brown/beige adipose tissues and the metabolic effects of various brown/beige adipose tissues secreted factors on other organs and tissues in endocrine/paracrine manners, and as well as on brown/beige adipose tissue itself in an autocrine manner. This will provide insights into understanding the potential secretory role of brown/beige adipose tissues in improving metabolic health.
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Affiliation(s)
- Bilal Ahmad
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, Subang Jaya, 47500, Malaysia
| | - Muhammad Sufyan Vohra
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, Subang Jaya, 47500, Malaysia
| | - Mansab Ali Saleemi
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, Subang Jaya, 47500, Malaysia
| | - Christopher J Serpell
- School of Physical Sciences, Ingram Building, University of Kent, Canterbury, Kent, CT2 7NH, United Kingdom
| | - Isabel Lim Fong
- Department of Paraclinical Sciences, Faculty of Medicine and Health Sciences Universiti Malaysia Sarawak (UNIMAS), Kota Samarahan, Sarawak, 94300, Malaysia
| | - Eng Hwa Wong
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, Subang Jaya, 47500, Malaysia.
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16
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Alizadeh M, Shahrbanian S, Hackney AC. Comparison of the effects of 12 weeks of three types of resistance training (traditional, circular and interval) on the levels of neuregulin 4, adiponectin and leptin in non-athletic men with obesity. ARCHIVOS DE MEDICINA DEL DEPORTE : PUBLICACION DE LA FEDERACION ESPANOLA DE MEDICINA DEL DEPORTE 2021; 38:389-396. [PMID: 35493286 PMCID: PMC9053093 DOI: 10.18176/archmeddeporte.00066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
OBJECTIVES The purpose of this study was to compare three types of resistance training including traditional, circular and interval in non-athletic men with obesity in comparison to a control group for neuregulin 4, adiponectin and leptin responses. MATERIAL AND METHOD The sample of the study included 44 non-athletic men with obesity, who were randomly divided into the 4 equal groups (10 per each group): traditional, circular, and interval resistance training as well as a control group. Neuregulin 4, leptin and adiponectin were analyzed using ELISA commercial kits. RESULTS The results of mixed-design ANOVA with repeated measures showed that there was a significant interaction between the type of resistance training used and time on neuregulin 4 (F (3, 40) = 80.22, P= 0.005, ES = 0.85), leptin (F (3, 40) = 27.53, P= 0.005, ES = 0.67) and adiponectin (F (3, 40) = 12.44, P= 0.005, ES = 0.48). Considering the main effect of groups, results indicated that there was a significant difference between types of resistance training and control group in neuregulin 4 (F (1, 40) =41.31, P=0.005, ES = 0.75), adiponectin (F (1, 40) =15.08, P=0.005, ES = 0.53) and leptin (F (1, 40) =32.05, P = 0.005, ES = 0.70). CONCLUSION Findings suggest that resistance training, especially interval resistance training can lead to increase the plasma level of neuregulin 4, adiponectin and decrease leptin in non-athletic men with obesity. Interval training showed superior effects on all study outcomes followed by circular and traditional training, respectively.
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Affiliation(s)
- Mona Alizadeh
- Department of Sport Science, Faculty of Humanities, Tarbiat Modares University, Tehran, Iran
| | - Shahnaz Shahrbanian
- Department of Sport Science, Faculty of Humanities, Tarbiat Modares University, Tehran, Iran
| | - Anthony C. Hackney
- Department of Exercise & Sport Science, University of North Carolina, Chapel Hill, NC 27599, USA
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17
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Pilkington AC, Paz HA, Wankhade UD. Beige Adipose Tissue Identification and Marker Specificity-Overview. Front Endocrinol (Lausanne) 2021; 12:599134. [PMID: 33776911 PMCID: PMC7996049 DOI: 10.3389/fendo.2021.599134] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 01/04/2021] [Indexed: 12/25/2022] Open
Abstract
Adipose tissue (AT) is classified based on its location, physiological and functional characteristics. Although there is a clear demarcation of anatomical and molecular features specific to white (WAT) and brown adipose tissue (BAT), the factors that uniquely differentiate beige AT (BeAT) remain to be fully elaborated. The ubiquitous presence of different types of AT and the inability to differentiate brown and beige adipocytes because of similar appearance present a challenge when classifying them one way or another. Here we will provide an overview of the latest advances in BeAT, BAT, and WAT identification based on transcript markers described in the literature. The review paper will highlight some of the difficulties these markers pose and will offer new perspectives on possible transcript-specific identification of BeAT. We hope that this will advance the understanding of the biology of different ATs. In addition, concrete strategies to distinguish different types of AT may be relevant to track the efficacy and mechanisms around interventions aimed to improve metabolic health and thwart excessive weight gain.
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Affiliation(s)
- Anna-Claire Pilkington
- Arkansas Children’s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Henry A. Paz
- Arkansas Children’s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR, United States
- Department of Pediatrics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Umesh D. Wankhade
- Arkansas Children’s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR, United States
- Department of Pediatrics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
- *Correspondence: Umesh D. Wankhade,
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18
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Wang R, Zhou W, Zhu X, Zhou N, Yang F, Sun B, Li X. Differences in Neuregulin 4 Expression in Children: Effects of Fat Depots and Obese Status. Endocr Res 2020; 45:190-201. [PMID: 31986906 DOI: 10.1080/07435800.2020.1721528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE To observe the expression of Nrg4, uncoupling protein-1 (UCP1), tumor necrosis factor α (TNFα), CD31, VE-cadherin/CDH5 and vascular endothelial growth factor A (VEGF-A) mRNA in abdominal subcutaneous (SC), omental (OM) adipose tissue in children with relation to anthropometric parameters. Further to verify the effect of inflammatory mediators on Nrg4 and UCP1 mRNA expression in adipocytes. METHODS Paired SC and OM adipose tissues were obtained from 58 children. In vitro, the adipocytes isolated from primary inguinal adipose tissue of mice were treated with TNFα (50 ng/ml) for 12-48 h. mRNA levels of Nrg4, UCP1 and TNFα were determined by real-time PCR. RESULTS Nrg4, UCP1, VEGF-A and CDH5 mRNA levels in SC were significantly higher than those in OM adipose tissue and the mRNA level of TNFα showed the opposite result. Moreover, Nrg4 and UCP1 mRNA in SC were significantly lower in overweight children compared to normal weight children. Nrg4 in SC and OM was negatively associated with BMISDS, WHtR. CDH55 mRNA in OM was negatively associated with WHR. VEGF-A was positively correlated with Nrg4 in SC. In vitro, Nrg4 and UCP1 mRNA levels in adipocytes were dose- and time-dependently decreased under TNFα treatment. CONCLUSIONS Nrg4, UCP1, VEGF-A and CDH5 mRNA expression in adipose tissues display a depot-specific pattern. Nrg4 mRNA levels in adipose tissue are decreased with obesity and associated with WAT browning and angiogenesis. TNFα may be involved in the regulation of Nrg4 level in adipose tissue, which may be one of the causes of the down-regulation of Nrg4 expression in obesity with chronic inflammatory response.
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Affiliation(s)
- Ran Wang
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Wei Zhou
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Xiaolei Zhu
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Nan Zhou
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Fan Yang
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Bin Sun
- Department of General Surgery, Children's Hospital of Nanjing Medical University , Nanjing, China
| | - Xiaonan Li
- Department of Children Health Care, Children's Hospital of Nanjing Medical University , Nanjing, China
- Institute of Pediatric Research, Nanjing Medical University , Nanjing, China
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19
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Gordon DM, Neifer KL, Hamoud ARA, Hawk CF, Nestor-Kalinoski AL, Miruzzi SA, Morran MP, Adeosun SO, Sarver JG, Erhardt PW, McCullumsmith RE, Stec DE, Hinds TD. Bilirubin remodels murine white adipose tissue by reshaping mitochondrial activity and the coregulator profile of peroxisome proliferator-activated receptor α. J Biol Chem 2020; 295:9804-9822. [PMID: 32404366 DOI: 10.1074/jbc.ra120.013700] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/11/2020] [Indexed: 12/18/2022] Open
Abstract
Activation of lipid-burning pathways in the fat-storing white adipose tissue (WAT) is a promising strategy to improve metabolic health and reduce obesity, insulin resistance, and type II diabetes. For unknown reasons, bilirubin levels are negatively associated with obesity and diabetes. Here, using mice and an array of approaches, including MRI to assess body composition, biochemical assays to measure bilirubin and fatty acids, MitoTracker-based mitochondrial analysis, immunofluorescence, and high-throughput coregulator analysis, we show that bilirubin functions as a molecular switch for the nuclear receptor transcription factor peroxisome proliferator-activated receptor α (PPARα). Bilirubin exerted its effects by recruiting and dissociating specific coregulators in WAT, driving the expression of PPARα target genes such as uncoupling protein 1 (Ucp1) and adrenoreceptor β 3 (Adrb3). We also found that bilirubin is a selective ligand for PPARα and does not affect the activities of the related proteins PPARγ and PPARδ. We further found that diet-induced obese mice with mild hyperbilirubinemia have reduced WAT size and an increased number of mitochondria, associated with a restructuring of PPARα-binding coregulators. We conclude that bilirubin strongly affects organismal body weight by reshaping the PPARα coregulator profile, remodeling WAT to improve metabolic function, and reducing fat accumulation.
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Affiliation(s)
- Darren M Gordon
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA.,Center for Diabetes and Endocrine Research (CeDER), University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Kari L Neifer
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Abdul-Rizaq Ali Hamoud
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Charles F Hawk
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Andrea L Nestor-Kalinoski
- Advanced Microscopy and Imaging Center, Department of Surgery, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Scott A Miruzzi
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Michael P Morran
- Advanced Microscopy and Imaging Center, Department of Surgery, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Samuel O Adeosun
- Department of Physiology and Biophysics, Cardiorenal and Metabolic Diseases Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Jeffrey G Sarver
- Center for Drug Design and Development (CD3), Department of Pharmacology and Experimental Therapeutics, University of Toledo College of Pharmacy and Pharmaceutical Sciences, Toledo, Ohio, USA
| | - Paul W Erhardt
- Center for Drug Design and Development (CD3), Department of Medicinal and Biological Chemistry, University of Toledo College of Pharmacy and Pharmaceutical Sciences, Toledo, Ohio, USA
| | - Robert E McCullumsmith
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA.,ProMedica, Toledo, Ohio, USA
| | - David E Stec
- Department of Physiology and Biophysics, Cardiorenal and Metabolic Diseases Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Terry D Hinds
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA .,Center for Diabetes and Endocrine Research (CeDER), University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
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Epigenetic Regulation of Neuregulin-1 Tunes White Adipose Stem Cell Differentiation. Cells 2020; 9:cells9051148. [PMID: 32392729 PMCID: PMC7290571 DOI: 10.3390/cells9051148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/01/2020] [Accepted: 05/04/2020] [Indexed: 11/17/2022] Open
Abstract
Expansion of subcutaneous adipose tissue by differentiation of new adipocytes has been linked to improvements in metabolic health. However, an expandability limit has been observed wherein new adipocytes cannot be produced, the existing adipocytes become enlarged (hypertrophic) and lipids spill over into ectopic sites. Inappropriate ectopic storage of these surplus lipids in liver, muscle, and visceral depots has been linked with metabolic dysfunction. Here we show that Neuregulin-1 (NRG1) serves as a regulator of adipogenic differentiation in subcutaneous primary human stem cells. We further demonstrate that DNA methylation modulates NRG1 expression in these cells, and a 3-day exposure of stem cells to a recombinant NRG1 peptide fragment is sufficient to reprogram adipogenic cellular differentiation to higher levels. These results define a novel molecular adipogenic rheostat with potential implications for the expansion of adipose tissue in vivo.
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21
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Selenium and Selenoproteins in Adipose Tissue Physiology and Obesity. Biomolecules 2020; 10:biom10040658. [PMID: 32344656 PMCID: PMC7225961 DOI: 10.3390/biom10040658] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/13/2020] [Accepted: 04/20/2020] [Indexed: 12/14/2022] Open
Abstract
Selenium (Se) homeostasis is tightly related to carbohydrate and lipid metabolism, but its possible roles in obesity development and in adipocyte metabolism are unclear. The objective of the present study is to review the current data on Se status in obesity and to discuss the interference between Se and selenoprotein metabolism in adipocyte physiology and obesity pathogenesis. The overview and meta-analysis of the studies on blood Se and selenoprotein P (SELENOP) levels, as well as glutathione peroxidase (GPX) activity in obese subjects, have yielded heterogenous and even conflicting results. Laboratory studies demonstrate that Se may modulate preadipocyte proliferation and adipogenic differentiation, and also interfere with insulin signaling, and regulate lipolysis. Knockout models have demonstrated that the selenoprotein machinery, including endoplasmic reticulum-resident selenoproteins together with GPXs and thioredoxin reductases (TXNRDs), are tightly related to adipocyte development and functioning. In conclusion, Se and selenoproteins appear to play an essential role in adipose tissue physiology, although human data are inconsistent. Taken together, these findings do not support the utility of Se supplementation to prevent or alleviate obesity in humans. Further human and laboratory studies are required to elucidate associations between Se metabolism and obesity.
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22
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Tutunchi H, Ostadrahimi A, Hosseinzadeh-Attar MJ, Miryan M, Mobasseri M, Ebrahimi-Mameghani M. A systematic review of the association of neuregulin 4, a brown fat-enriched secreted factor, with obesity and related metabolic disturbances. Obes Rev 2020; 21:e12952. [PMID: 31782243 DOI: 10.1111/obr.12952] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/05/2019] [Accepted: 09/05/2019] [Indexed: 12/13/2022]
Abstract
Neuregulin 4 (Nrg4), a novel brown fat-enriched hormone, plays a key role in the modulation of glucose and lipid metabolism and energy balance. Recent data have demonstrated that the expression of Nrg4 is substantially down-regulated in mouse and human obesity, making its regulatory aspect intriguing. Because of the close relationship between Nrg4, obesity, and associated metabolic diseases, this systematic review aimed to assess the association of Nrg4 with obesity and related metabolic disturbances, emphasizing its possible mechanisms of action in these disorders. We searched PubMed/Medline, ScienceDirect, Scopus, EMBASE, ProQuest, and Google Scholar up until June 2019. The evidence reviewed here indicates that Nrg4 may contribute to the prevention of obesity and related metabolic complications by elevating brown adipose tissue activity, increasing the expression of thermogenic markers, decreasing the expression of lipogenic/adipogenic genes, exacerbating white adipose tissue browning, increasing the number of brite/beige adipocytes, promoting hepatic fat oxidation and ketogenesis, inducing neurite outgrowth, enhancing blood vessels in adipose tissue, increasing the circulatory levels of healthy adipokines, and improving glucose homeostasis. Thus, Nrg4 appears to be a novel therapeutic strategy for the treatment of obesity and associated metabolic complications. However, prospective cohort studies are warranted to confirm these outcomes.
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Affiliation(s)
- Helda Tutunchi
- Nutrition Research Center, Student Research Committee, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Ostadrahimi
- Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mahsa Miryan
- Nutrition Research Center, Student Research Committee, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Majid Mobasseri
- Endocrine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mehrangiz Ebrahimi-Mameghani
- Social Determinants of Health Research Center, Department of Biochemistry and Diet Therapy, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
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Catalina MOS, Redondo PC, Granados MP, Cantonero C, Sanchez-Collado J, Albarran L, Lopez JJ. New Insights into Adipokines as Potential Biomarkers for Type-2 Diabetes Mellitus. Curr Med Chem 2019; 26:4119-4144. [PMID: 29210636 DOI: 10.2174/0929867325666171205162248] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 02/06/2023]
Abstract
A large number of studies have been focused on investigating serum biomarkers associated with risk or diagnosis of type-2 diabetes mellitus. In the last decade, promising studies have shown that circulating levels of adipokines could be used as a relevant biomarker for diabetes mellitus progression as well as therapeutic future targets. Here, we discuss the possible use of recently described adipokines, including apelin, omentin-1, resistin, FGF-21, neuregulin-4 and visfatin, as early biomarkers for diabetes. In addition, we also include recent findings of other well known adipokines such as leptin and adiponectin. In conclusion, further studies are needed to clarify the pathophysiological significance and clinical value of these biological factors as potential biomarkers in type-2 diabetes and related dysfunctions.
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Affiliation(s)
| | - Pedro C Redondo
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, 10003-Caceres, Spain
| | - Maria P Granados
- Aldea Moret's Medical Center, Extremadura Health Service, 10195-Caceres, Spain
| | - Carlos Cantonero
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, 10003-Caceres, Spain
| | - Jose Sanchez-Collado
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, 10003-Caceres, Spain
| | - Letizia Albarran
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, 10003-Caceres, Spain
| | - Jose J Lopez
- Department of Physiology (Cell Physiology Research Group), University of Extremadura, 10003-Caceres, Spain
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24
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Lee JH, Park A, Oh KJ, Lee SC, Kim WK, Bae KH. The Role of Adipose Tissue Mitochondria: Regulation of Mitochondrial Function for the Treatment of Metabolic Diseases. Int J Mol Sci 2019; 20:ijms20194924. [PMID: 31590292 PMCID: PMC6801758 DOI: 10.3390/ijms20194924] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/29/2019] [Accepted: 09/30/2019] [Indexed: 02/07/2023] Open
Abstract
: Mitochondria play a key role in maintaining energy homeostasis in metabolic tissues, including adipose tissues. The two main types of adipose tissues are the white adipose tissue (WAT) and the brown adipose tissue (BAT). WAT primarily stores excess energy, whereas BAT is predominantly responsible for energy expenditure by non-shivering thermogenesis through the mitochondria. WAT in response to appropriate stimuli such as cold exposure and β-adrenergic agonist undergoes browning wherein it acts as BAT, which is characterized by the presence of a higher number of mitochondria. Mitochondrial dysfunction in adipocytes has been reported to have strong correlation with metabolic diseases, including obesity and type 2 diabetes. Dysfunction of mitochondria results in detrimental effects on adipocyte differentiation, lipid metabolism, insulin sensitivity, oxidative capacity, and thermogenesis, which consequently lead to metabolic diseases. Recent studies have shown that mitochondrial function can be improved by using thiazolidinedione, mitochondria-targeted antioxidants, and dietary natural compounds; by performing exercise; and by controlling caloric restriction, thereby maintaining the metabolic homeostasis by inducing adaptive thermogenesis of BAT and browning of WAT. In this review, we focus on and summarize the molecular regulation involved in the improvement of mitochondrial function in adipose tissues so that strategies can be developed to treat metabolic diseases.
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Affiliation(s)
- Jae Ho Lee
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
| | - Anna Park
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
| | - Kyoung-Jin Oh
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea
| | - Sang Chul Lee
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea
| | - Won Kon Kim
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea.
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea.
| | - Kwang-Hee Bae
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea.
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea.
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25
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Scheja L, Heeren J. The endocrine function of adipose tissues in health and cardiometabolic disease. Nat Rev Endocrinol 2019; 15:507-524. [PMID: 31296970 DOI: 10.1038/s41574-019-0230-6] [Citation(s) in RCA: 322] [Impact Index Per Article: 64.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2019] [Indexed: 12/16/2022]
Abstract
In addition to their role in glucose and lipid metabolism, adipocytes respond differentially to physiological cues or metabolic stress by releasing endocrine factors that regulate diverse processes, such as energy expenditure, appetite control, glucose homeostasis, insulin sensitivity, inflammation and tissue repair. Both energy-storing white adipocytes and thermogenic brown and beige adipocytes secrete hormones, which can be peptides (adipokines), lipids (lipokines) and exosomal microRNAs. Some of these factors have defined targets; for example, adiponectin and leptin signal through their respective receptors that are expressed in multiple organs. For other adipocyte hormones, receptors are more promiscuous or remain to be identified. Furthermore, many of these hormones are also produced by other organs and tissues, which makes defining the endocrine contribution of adipose tissues a challenge. In this Review, we discuss the functional role of adipose tissue-derived endocrine hormones for metabolic adaptations to the environment and we highlight how these factors contribute to the development of cardiometabolic diseases. We also cover how this knowledge can be translated into human therapies. In addition, we discuss recent findings that emphasize the endocrine role of white versus thermogenic adipocytes in conditions of health and disease.
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Affiliation(s)
- Ludger Scheja
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Li M, Chen Y, Jiang J, Lu Y, Song Z, Zhang S, Sun C, Ying H, Fan X, Song Y, Yang J, Zhao L. Elevated serum neuregulin 4 levels in patients with hyperthyroidism. Endocr Connect 2019; 8:728-735. [PMID: 31063974 PMCID: PMC6547303 DOI: 10.1530/ec-19-0175] [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: 04/22/2019] [Accepted: 05/07/2019] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Recent studies have shown that neuregulin 4 (Nrg4), a member of the epidermal growth factor (EGF) family of extracellular ligands, plays an important role in the prevention of obesity, insulin resistance and nonalcoholic fatty liver disease (NAFLD). Considering that thyroid hormone (TH) has profound effects on whole-body energy metabolism, we speculate that circulating Nrg4 levels might be altered in patients with hyperthyroidism. DESIGN AND METHODS A total of 129 hyperthyroid patients and 100 healthy subjects were recruited. Of them, 39 hyperthyroid patients received thionamide treatment for 3 months until euthyroidism. Serum Nrg4 levels were determined using the ELISA method. To further confirm the relationship between TH and Nrg4, C57BL/6 mice were treated with T3 and quantitative real-time PCR was performed to detect Nrg4 gene expression. RESULTS Serum Nrg4 levels were significantly elevated in hyperthyroid patients as compared with normal controls (3.84 ± 1.63 vs 2.21 ± 1.04 ng/mL, P < 0.001). After achieving euthyroidism by thionamide treatment, serum Nrg4 levels dropped markedly from 3.57 ± 1.26 to 1.94 ± 0.72 ng/ml (P < 0.001). After adjustment for potential confounders, serum Nrg4 levels were independently associated with hyperthyroidism. The upregulation of Nrg4 expression in the livers and white adipose tissues by T3 was further confirmed by animal and cell culture experiments. CONCLUSIONS Serum Nrg4 levels were increased in patients with hyperthyroidism. The liver and white adipose tissue might be primary sources contributing to elevated serum Nrg4 concentrations.
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Affiliation(s)
- Min Li
- Department of Endocrinology and Metabolism, Fudan Institute of Metabolic Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Ying Chen
- Department of Endocrinology and Metabolism, Fudan Institute of Metabolic Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jingjing Jiang
- Department of Endocrinology and Metabolism, Fudan Institute of Metabolic Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yan Lu
- Department of Endocrinology and Metabolism, Fudan Institute of Metabolic Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Zhiyi Song
- Department of Endocrinology and Metabolism, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shengjie Zhang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Chao Sun
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Hao Ying
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Xiaofang Fan
- Department of Endocrinology and Metabolism, Minhang Branch, Zhongshan Hospital, Central Hospital of Minhang District, Shanghai Minhang Hospital, Fudan University, Shanghai, China
| | - Yuping Song
- Department of Endocrinology and Metabolism, Minhang Branch, Zhongshan Hospital, Central Hospital of Minhang District, Shanghai Minhang Hospital, Fudan University, Shanghai, China
- Correspondence should be addressed to Y Song or J Yang or L Zhao: or or
| | - Jialin Yang
- Department of Endocrinology and Metabolism, Minhang Branch, Zhongshan Hospital, Central Hospital of Minhang District, Shanghai Minhang Hospital, Fudan University, Shanghai, China
- Correspondence should be addressed to Y Song or J Yang or L Zhao: or or
| | - Lin Zhao
- Department of Endocrinology and Metabolism, Fudan Institute of Metabolic Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
- Correspondence should be addressed to Y Song or J Yang or L Zhao: or or
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Guilherme A, Henriques F, Bedard AH, Czech MP. Molecular pathways linking adipose innervation to insulin action in obesity and diabetes mellitus. Nat Rev Endocrinol 2019; 15:207-225. [PMID: 30733616 PMCID: PMC7073451 DOI: 10.1038/s41574-019-0165-y] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adipose tissue comprises adipocytes and many other cell types that engage in dynamic crosstalk in a highly innervated and vascularized tissue matrix. Although adipose tissue has been studied for decades, it has been appreciated only in the past 5 years that extensive arborization of nerve fibres has a dominant role in regulating the function of adipose tissue. This Review summarizes the latest literature, which suggests that adipocytes signal to local sensory nerve fibres in response to perturbations in lipolysis and lipogenesis. Such adipocyte signalling to the central nervous system causes sympathetic output to distant adipose depots and potentially other metabolic tissues to regulate systemic glucose homeostasis. Paracrine factors identified in the past few years that mediate such adipocyte-neuron crosstalk are also reviewed. Similarly, immune cells and endothelial cells within adipose tissue communicate with local nerve fibres to modulate neurotransmitter tone, blood flow, adipocyte differentiation and energy expenditure, including adipose browning to produce heat. This understudied field of neurometabolism related to adipose tissue biology has great potential to reveal new mechanistic insights and potential therapeutic strategies for obesity and type 2 diabetes mellitus.
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Affiliation(s)
- Adilson Guilherme
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Felipe Henriques
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Alexander H Bedard
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
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28
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Li M, Hao Z, Wanlong Z, Zhengkun W. Seasonal variations of adipose tissue in Tupaia belangeri (Mammalia: Scandentia: Tupaiidae). THE EUROPEAN ZOOLOGICAL JOURNAL 2019. [DOI: 10.1080/24750263.2019.1572798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- M. Li
- Key Laboratory of Adaptive Evolution and Ecological Conservation on Plants and Animals in Southwest Mountain Ecosystem of Yunnan Higher Education Institutes, School of Life Sciences, Yunnan Normal University, Kunming, People’s Republic of China
| | - Z. Hao
- Key Laboratory of Adaptive Evolution and Ecological Conservation on Plants and Animals in Southwest Mountain Ecosystem of Yunnan Higher Education Institutes, School of Life Sciences, Yunnan Normal University, Kunming, People’s Republic of China
| | - Z. Wanlong
- Key Laboratory of Adaptive Evolution and Ecological Conservation on Plants and Animals in Southwest Mountain Ecosystem of Yunnan Higher Education Institutes, School of Life Sciences, Yunnan Normal University, Kunming, People’s Republic of China
| | - W. Zhengkun
- Key Laboratory of Adaptive Evolution and Ecological Conservation on Plants and Animals in Southwest Mountain Ecosystem of Yunnan Higher Education Institutes, School of Life Sciences, Yunnan Normal University, Kunming, People’s Republic of China
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Peres Valgas da Silva C, Hernández-Saavedra D, White JD, Stanford KI. Cold and Exercise: Therapeutic Tools to Activate Brown Adipose Tissue and Combat Obesity. BIOLOGY 2019; 8:biology8010009. [PMID: 30759802 PMCID: PMC6466122 DOI: 10.3390/biology8010009] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 12/11/2022]
Abstract
The rise in obesity over the last several decades has reached pandemic proportions. Brown adipose tissue (BAT) is a thermogenic organ that is involved in energy expenditure and represents an attractive target to combat both obesity and type 2 diabetes. Cold exposure and exercise training are two stimuli that have been investigated with respect to BAT activation, metabolism, and the contribution of BAT to metabolic health. These two stimuli are of great interest because they have both disparate and converging effects on BAT activation and metabolism. Cold exposure is an effective mechanism to stimulate BAT activity and increase glucose and lipid uptake through mitochondrial uncoupling, resulting in metabolic benefits including elevated energy expenditure and increased insulin sensitivity. Exercise is a therapeutic tool that has marked benefits on systemic metabolism and affects several tissues, including BAT. Compared to cold exposure, studies focused on BAT metabolism and exercise display conflicting results; the majority of studies in rodents and humans demonstrate a reduction in BAT activity and reduced glucose and lipid uptake and storage. In addition to investigations of energy uptake and utilization, recent studies have focused on the effects of cold exposure and exercise on the structural lipids in BAT and secreted factors released from BAT, termed batokines. Cold exposure and exercise induce opposite responses in terms of structural lipids, but an important overlap exists between the effects of cold and exercise on batokines. In this review, we will discuss the similarities and differences of cold exposure and exercise in relation to their effects on BAT activity and metabolism and its relevance for the prevention of obesity and the development of type 2 diabetes.
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Affiliation(s)
- Carmem Peres Valgas da Silva
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Diego Hernández-Saavedra
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Joseph D White
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Kristin I Stanford
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
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Abstract
Brown adipocytes are the key cell type in brown adipose tissue (BAT) that express the genes required for heat production through the process of thermogenesis. Brown adipocyte cell culture models are important for researching the molecular pathways that control cell autonomous processes. In vitro tools for the study of brown adipocytes include BAT explant cultures and BAT primary cultures that are first proliferated and then differentiated. A number of stable brown preadipocyte cell lines have been generated by the expression transforming factors such as SV40 T antigen. The application of these cell lines reduces the requirement for animal tissue which is needed for primary culture and explants. Furthermore, brown adipocyte cell lines that effectively recapitulate the properties of brown adipocytes permit large-scale experimental procedures that are generally unfeasible with primary cultures that undergo a restricted number of cell divisions. Cell lines are valuable for applications such as large-scale endogenous protein expression, ChIP assay, and procedures requiring antibiotic selection over several cell divisions including stable exogenous gene expression and CRISR/Cas9 gene editing.
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Affiliation(s)
- Mark Christian
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
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31
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Tian QP, Liu ML, Tang CS, Xue L, Pang YZ, Qi YF. Association of Circulating Neuregulin-4 with Presence and Severity of Coronary Artery Disease. Int Heart J 2018; 60:45-49. [PMID: 30393265 DOI: 10.1536/ihj.18-130] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Neuregulin-4 (Nrg4) is a newly discovered adipokine that is synthesized in many tissues and plays an important role in modulating systemic energy metabolism and in the development of metabolic disorders. However, little is known about the relationship between Nrg4 and coronary artery disease (CAD). In this study, we investigated the association between Nrg4 and the presence and severity of CAD.We enrolled 73 patients diagnosed by coronary angiography (CAG) as having CAD and 32 controls. The CAD group was divided into two subgroups according to their SYNTAX score. Plasma levels of Nrg4 were measured in all participants and compared among different groups. The relationship between Nrg4 and CAD was analyzed. Receiver operating characteristic (ROC) analysis was conducted to evaluate the usefulness Nrg4 in assessing the presence and severity of CAD.Nrg4 levels were negatively associated with the SYNTAX score (r = -0.401, P = 0.000). The patients with a higher SYNTAX score had significantly lower Nrg4 levels as compared with the low SYNTAX score subgroup and the controls (P < 0.05). The Nrg4 levels of the low SYNTAX score subgroup were much lower than controls (P < 0.05). Furthermore, an association between Nrg4 and CAD (odds ratio, 0.279; 95% confidence interval, 0.088-0.882) was observed. Nrg4 had 43.8% sensitivity and 96.9% specificity for identifying CAD, and 73.1% sensitivity and 87.3% specificity for identifying patients who had severe coronary artery lesions.Nrg4 levels were found to be inversely associated with the presence and severity of CAD.
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Affiliation(s)
- Qing-Ping Tian
- Department of Geriatrics, Peking University First Hospital
| | - Mei-Lin Liu
- Department of Geriatrics, Peking University First Hospital
| | - Chao-Shu Tang
- Institute of Cardiovascular Disease, Peking University First Hospital
| | - Lin Xue
- Department of Cardiology, Peking University First Hospital
| | - Yong-Zheng Pang
- Institute of Cardiovascular Disease, Peking University First Hospital
| | - Yong-Fen Qi
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, School of Basic Medical Sciences, Peking University Health Science Center
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32
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Zeng F, Wang Y, Kloepfer LA, Wang S, Harris RC. ErbB4 deletion predisposes to development of metabolic syndrome in mice. Am J Physiol Endocrinol Metab 2018; 315:E583-E593. [PMID: 29944391 PMCID: PMC6230712 DOI: 10.1152/ajpendo.00166.2018] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/25/2018] [Accepted: 06/25/2018] [Indexed: 01/13/2023]
Abstract
ErbB4, a member of the EGF receptor family, plays a variety of roles in physiological and pathological states. Genetic studies have indicated a link between ErbB4 and type 2 diabetes and obesity, but its role in metabolic syndrome (MetS) has not been reported. In the current study we found that mice with ErbB4 deletion developed MetS after 24 wk on a medium-fat diet (MFD), as indicated by development of obesity, dyslipidemia, hepatic steatosis, hyperglycemia, hyperinsulinemia, and insulin resistance, compared with wild-type mice. ErbB4 deletion mice also exhibited increased amounts of subcutaneous and visceral fat, with increased serum leptin levels, compared with wild-type mice, whereas levels of adiponectin were not significantly different. Histologically, severe inflammation, indicated by F4/80 immunostaining and M1 macrophage polarization, was detected in inguinal and epididymal white adipose tissue in ErbB4 deletion mice. ErbB4 expression decreased during 3T3-L1 preadipocyte differentiation. Administration of neuroregulin 4, a specific ligand for ErbB4, to 3T3-L1 adipocytes had no effect on adipogenesis and lipolysis but significantly inhibited lipogenesis, promoted browning, induced GLUT4 redistribution to the cell membrane, and increased glucose uptake. Neuroregulin 4 also significantly increased glucose uptake in adipocytes isolated from wild-type mice, while these effects were significantly decreased in adipocytes isolated from ErbB4 deletion mice. In conclusion, our results indicate that ErbB4 may play an important role in glucose homeostasis and lipogenesis. ErbB4 deficiency-related obesity and adipose tissue inflammation may contribute to the development of MetS.
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Affiliation(s)
- Fenghua Zeng
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center , Nashville, Tennessee
| | - Yinqiu Wang
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center , Nashville, Tennessee
| | - Lance A Kloepfer
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center , Nashville, Tennessee
| | - Suwan Wang
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center , Nashville, Tennessee
| | - Raymond C Harris
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center , Nashville, Tennessee
- Department of Veterans Affairs , Nashville, Tennessee
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Guilherme A, Pedersen DJ, Henriques F, Bedard AH, Henchey E, Kelly M, Morgan DA, Rahmouni K, Czech MP. Neuronal modulation of brown adipose activity through perturbation of white adipocyte lipogenesis. Mol Metab 2018; 16:116-125. [PMID: 30005879 PMCID: PMC6157614 DOI: 10.1016/j.molmet.2018.06.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/13/2018] [Accepted: 06/25/2018] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE Crosstalk between adipocytes and local neurons may be an important regulatory mechanism to control energy homeostasis. We previously reported that perturbation of adipocyte de novo lipogenesis (DNL) by deletion of fatty acid synthase (FASN) expands sympathetic neurons within white adipose tissue (WAT) and stimulates the appearance of "beige" adipocytes. Here we tested whether WAT DNL activity can also influence neuronal regulation and thermogenesis in brown adipose tissue (BAT). METHODS AND RESULTS Induced deletion of FASN in all adipocytes in mature mice (iAdFASNKO) enhanced sympathetic innervation and neuronal activity as well as UCP1 expression in both WAT and BAT. This increased sympathetic innervation could be observed at both 22 °C and 30 °C, indicating it is not a response to heat loss but rather adipocyte signaling. In contrast, selective ablation of FASN in brown adipocytes of mice (iUCP1FASNKO) failed to modulate sympathetic innervation and the thermogenic program in BAT. Surprisingly, DNL in brown adipocytes was also dispensable in maintaining euthermia when UCP1FASNKO mice were cold-exposed. CONCLUSION These results indicate that DNL in white adipocytes influences long distance signaling to BAT, which can modify BAT sympathetic innervation and expression of genes involved in thermogenesis.
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Affiliation(s)
- Adilson Guilherme
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - David J Pedersen
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Felipe Henriques
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Alexander H Bedard
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Elizabeth Henchey
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Mark Kelly
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Donald A Morgan
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
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Affiliation(s)
- Saverio Cinti
- Professor of Human Anatomy, Director, Center of Obesity, University of Ancona (Politecnica delle Marche), Ancona, Italy
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Plasma Neuregulin 4 Levels Are Associated with Metabolic Syndrome in Patients Newly Diagnosed with Type 2 Diabetes Mellitus. DISEASE MARKERS 2018; 2018:6974191. [PMID: 29721105 PMCID: PMC5867541 DOI: 10.1155/2018/6974191] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 01/16/2018] [Indexed: 12/20/2022]
Abstract
Neuregulin 4 (Nrg4) has been proposed to play a role in the pathogeneses of obesity, insulin resistance, and dyslipidemia. However, information about the link between Nrg4 and metabolic syndrome (MetS) is scarce, especially in patients with newly diagnosed type 2 diabetes mellitus (nT2DM). This study aimed at investigating whether Nrg4 is associated with MetS in nT2DM patients. A total of 311 patients with nT2DM were recruited. Plasma Nrg4 concentration was determined by ELISA. Plasma Nrg4 concentration was lower in nT2DM patients with MetS than in nT2DM patients without MetS (P = 0.001). Nrg4 concentration showed negative correlations with most of the analyzed indicators of MetS. MetS was less prevalent among subjects in the highest quartile of plasma Nrg4 concentration than among those in the lowest quartile (P < 0.01). Age- and sex-adjusted plasma Nrg4 concentrations were positively correlated with concentrations of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A (both P < 0.05) and negatively correlated with triglyceride, high-sensitivity C-reactive protein (hs-CRP), and gamma-glutamyltransferase concentrations, neutrophil count, and white blood cell (WBC) count (all P < 0.05). In multivariate analysis, Nrg4 was independently associated with hs-CRP level, WBC count, and HDL-C level (P = 0.001 or P < 0.05). Multiple logistic regression analysis of MetS prediction by Nrg4 revealed an odds ratio of 0.560 (95% CI: 0.374-0.837; P < 0.01). Decreased plasma Nrg4 levels, which may be associated with augmented oxidative stress, inflammation, and dyslipidemia, might be involved in the development of MetS in nT2DM patients.
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Defour M, Dijk W, Ruppert P, Nascimento EBM, Schrauwen P, Kersten S. The Peroxisome Proliferator-Activated Receptor α is dispensable for cold-induced adipose tissue browning in mice. Mol Metab 2018; 10:39-54. [PMID: 29455954 PMCID: PMC5985232 DOI: 10.1016/j.molmet.2018.01.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 01/25/2018] [Accepted: 01/31/2018] [Indexed: 11/23/2022] Open
Abstract
Objective Chronic cold exposure causes white adipose tissue (WAT) to adopt features of brown adipose tissue (BAT), a process known as browning. Previous studies have hinted at a possible role for the transcription factor Peroxisome Proliferator-Activated Receptor alpha (PPARα) in cold-induced browning. Here we aimed to investigate the importance of PPARα in driving transcriptional changes during cold-induced browning in mice. Methods Male wildtype and PPARα−/− mice were housed at thermoneutrality (28 °C) or cold (5 °C) for 10 days. Whole genome expression analysis was performed on inguinal WAT. In addition, other analyses were carried out. Whole genome expression data of livers of wildtype and PPARα−/− mice fasted for 24 h served as positive control for PPARα-dependent gene regulation. Results Cold exposure increased food intake and decreased weight of BAT and WAT to a similar extent in wildtype and PPARα−/− mice. Except for plasma non-esterified fatty acids, none of the cold-induced changes in plasma metabolites were dependent on PPARα genotype. Histological analysis of inguinal WAT showed clear browning upon cold exposure but did not reveal any morphological differences between wildtype and PPARα−/− mice. Transcriptomics analysis of inguinal WAT showed a marked effect of cold on overall gene expression, as revealed by principle component analysis and hierarchical clustering. However, wildtype and PPARα−/− mice clustered together, even after cold exposure, indicating a similar overall gene expression profile in the two genotypes. Pathway analysis revealed that cold upregulated pathways involved in energy usage, oxidative phosphorylation, and fatty acid β-oxidation to a similar extent in wildtype and PPARα−/− mice. Furthermore, cold-mediated induction of genes related to thermogenesis such as Ucp1, Elovl3, Cox7a1, Cox8, and Cidea, as well as many PPAR target genes, was similar in wildtype and PPARα−/− mice. Finally, pharmacological PPARα activation had a minimal effect on expression of cold-induced genes in murine WAT. Conclusion Cold-induced changes in gene expression in inguinal WAT are unaltered in mice lacking PPARα, indicating that PPARα is dispensable for cold-induced browning. Chronic cold markedly induces PPARα expression in inguinal fat. Cold exposure causes transient hypothermia in PPARα−/− mice. Chronic cold-induced changes in gene expression in inguinal fat are unaltered in PPARα−/− mice. Chronic cold does not lead to PPARα activation in liver.
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Affiliation(s)
- Merel Defour
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Wieneke Dijk
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Philip Ruppert
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Emmani B M Nascimento
- Department of Human Biology and Human Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, PO Box 616, 6200 MD Maastricht, The Netherlands
| | - Patrick Schrauwen
- Department of Human Biology and Human Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, PO Box 616, 6200 MD Maastricht, The Netherlands
| | - Sander Kersten
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands.
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Page MM, Skovsø S, Cen H, Chiu AP, Dionne DA, Hutchinson DF, Lim GE, Szabat M, Flibotte S, Sinha S, Nislow C, Rodrigues B, Johnson JD. Reducing insulin via conditional partial gene ablation in adults reverses diet-induced weight gain. FASEB J 2018; 32:1196-1206. [PMID: 29122848 PMCID: PMC5892722 DOI: 10.1096/fj.201700518r] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Excess circulating insulin is associated with obesity in humans and in animal models. However, the physiologic causality of hyperinsulinemia in adult obesity has rightfully been questioned because of the absence of clear evidence that weight loss can be induced by acutely reversing diet-induced hyperinsulinemia. Herein, we describe the consequences of inducible, partial insulin gene deletion in a mouse model in which animals have already been made obese by consuming a high-fat diet. A modest reduction in insulin production/secretion was sufficient to cause significant weight loss within 5 wk, with a specific effect on visceral adipose tissue. This result was associated with a reduction in the protein abundance of the lipodystrophy gene polymerase I and transcript release factor ( Ptrf; Cavin) in gonadal adipose tissue. RNAseq analysis showed that reduced insulin and weight loss also associated with a signature of reduced innate immunity. This study demonstrates that changes in circulating insulin that are too fine to adversely affect glucose homeostasis nonetheless exert control over adiposity.-Page, M. M., Skovsø, S., Cen, H., Chiu, A. P., Dionne, D. A., Hutchinson, D. F., Lim, G. E., Szabat, M., Flibotte, S., Sinha, S., Nislow, C., Rodrigues, B., Johnson, J. D. Reducing insulin via conditional partial gene ablation in adults reverses diet-induced weight gain.
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Affiliation(s)
- Melissa M Page
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Søs Skovsø
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Haoning Cen
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amy P Chiu
- Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Derek A Dionne
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Daria F Hutchinson
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gareth E Lim
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marta Szabat
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephane Flibotte
- Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sunita Sinha
- Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Corey Nislow
- Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian Rodrigues
- Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - James D Johnson
- Department of Cellular and Physiological Sciences, Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
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Tapia P, Fernández-Galilea M, Robledo F, Mardones P, Galgani JE, Cortés VA. Biology and pathological implications of brown adipose tissue: promises and caveats for the control of obesity and its associated complications. Biol Rev Camb Philos Soc 2017; 93:1145-1164. [DOI: 10.1111/brv.12389] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 11/10/2017] [Accepted: 11/14/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Pablo Tapia
- Department of Nutrition, Diabetes and Metabolism, School of Medicine; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
| | - Marta Fernández-Galilea
- Department of Nutrition, Diabetes and Metabolism, School of Medicine; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
| | - Fermín Robledo
- Department of Nutrition, Diabetes and Metabolism, School of Medicine; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
| | - Pablo Mardones
- Research and Innovation Office, School of Engineering; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
| | - José E. Galgani
- Department of Nutrition, Diabetes and Metabolism, School of Medicine; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
- Departamento Ciencias de la Salud; Carrera de Nutrición y Dietética, Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
| | - Víctor A. Cortés
- Department of Nutrition, Diabetes and Metabolism, School of Medicine; Pontificia Universidad Católica de Chile, Marcoleta 367; Santiago, 8330024 Chile
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Yan PJ, Xu Y, Wan Q, Feng J, Li H, Gao CL, Yang J, Zhong HH, Zhang ZH. Decreased plasma neuregulin 4 concentration is associated with increased high-sensitivity C-reactive protein in newly diagnosed type 2 diabetes mellitus patients: a cross-sectional study. Acta Diabetol 2017; 54:1091-1099. [PMID: 28918492 DOI: 10.1007/s00592-017-1044-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 08/21/2017] [Indexed: 12/18/2022]
Abstract
AIMS Inflammation has been reported to be involved in the pathogenesis of atherosclerosis. This principal objective of this study was to investigate if the secretion of neuregulin 4 (Nrg4), a soluble protein associated with metabolic syndrome and subclinical cardiovascular disease, is correlated with the inflammation marker high-sensitivity C-reactive protein (hs-CRP) in patients with newly diagnosed type 2 diabetes mellitus (nT2DM). METHODS A study group of 311 nT2DM patients was divided into three subgroups based on hs-CRP tertiles. Multiple linear regression was conducted to explore the association between plasma Nrg4 and hs-CRP levels. RESULTS The nT2DM patients with the highest hs-CRP levels (>2.46 mg/L) exhibited higher atherogenic coefficients and atherogenic index of plasma (AIP) levels, but lower levels of plasma Nrg4, as compared to those with the lowest hs-CRP levels (<0.63 mg/L). Plasma Nrg4 levels were inversely associated with white blood cell count, hs-CRP, and AIP and positively associated with high-density lipoprotein cholesterol (HDL-C), before and after adjustment for age, gender, body mass index (BMI), and body fat percentage (P < 0.01 or P < 0.05). hs-CRP was the factor most strongly associated with plasma Nrg4 levels. CONCLUSIONS These results indicate that lower plasma Nrg4 levels may be associated with elevated hs-CRP in nT2DM patients. It generates the hypothesis that decreased levels of Nrg4 may trigger the development of atherosclerosis through its proinflammatory effects. These findings need to be confirmed by further prospective studies.
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Affiliation(s)
- Pi-Jun Yan
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Yong Xu
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Qin Wan
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Jian Feng
- Department of Cardiovascular Medicine, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Hua Li
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Chen-Lin Gao
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Jun Yang
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Hai-Hua Zhong
- Department of Endocrinology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Zhi-Hong Zhang
- Department of General Medicine, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
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Milet C, Bléher M, Allbright K, Orgeur M, Coulpier F, Duprez D, Havis E. Egr1 deficiency induces browning of inguinal subcutaneous white adipose tissue in mice. Sci Rep 2017; 7:16153. [PMID: 29170465 PMCID: PMC5701004 DOI: 10.1038/s41598-017-16543-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 11/15/2017] [Indexed: 12/12/2022] Open
Abstract
Beige adipocyte differentiation within white adipose tissue, referred to as browning, is seen as a possible mechanism for increasing energy expenditure. The molecular regulation underlying the thermogenic browning process has not been entirely elucidated. Here, we identify the zinc finger transcription factor EGR1 as a negative regulator of the beige fat program. Loss of Egr1 in mice promotes browning in the absence of external stimulation and leads to an increase of Ucp1 expression, which encodes the key thermogenic mitochondrial uncoupling protein-1. Moreover, EGR1 is recruited to the proximal region of the Ucp1 promoter in subcutaneous inguinal white adipose tissue. Transcriptomic analysis of subcutaneous inguinal white adipose tissue in the absence of Egr1 identifies the molecular signature of white adipocyte browning downstream of Egr1 deletion and highlights a concomitant increase of beige differentiation marker and a decrease in extracellular matrix gene expression. Conversely, Egr1 overexpression in mesenchymal stem cells decreases beige adipocyte differentiation, while increasing extracellular matrix production. These results reveal a role for Egr1 in blocking energy expenditure via direct Ucp1 transcription repression and highlight Egr1 as a therapeutic target for counteracting obesity.
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Affiliation(s)
- Cécile Milet
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, Inserm U1156, IBPS-Developmental Biology Laboratory, F-75005, Paris, France
| | - Marianne Bléher
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, Inserm U1156, IBPS-Developmental Biology Laboratory, F-75005, Paris, France
| | | | - Mickael Orgeur
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, Inserm U1156, IBPS-Developmental Biology Laboratory, F-75005, Paris, France
| | - Fanny Coulpier
- École normale supérieure, PSL Research University, CNRS, Inserm, Institut de Biologie de l'École normale supérieure (IBENS), Plateforme Génomique, 75005, Paris, France
| | - Delphine Duprez
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, Inserm U1156, IBPS-Developmental Biology Laboratory, F-75005, Paris, France.
| | - Emmanuelle Havis
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, Inserm U1156, IBPS-Developmental Biology Laboratory, F-75005, Paris, France.
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Henry BA, Pope M, Birtwistle M, Loughnan R, Alagal R, Fuller-Jackson JP, Perry V, Budge H, Clarke IJ, Symonds ME. Ontogeny and Thermogenic Role for Sternal Fat in Female Sheep. Endocrinology 2017; 158:2212-2225. [PMID: 28431116 DOI: 10.1210/en.2017-00081] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/14/2017] [Indexed: 02/05/2023]
Abstract
Brown adipose tissue acting through a unique uncoupling protein (UCP1) has a critical role in preventing hypothermia in newborn sheep but is then thought to rapidly disappear during postnatal life. The extent to which the anatomical location of fat influences postnatal development and thermogenic function in adulthood, particularly following feeding, is unknown, and we examined both in our study. Changes in gene expression of functionally important pathways (i.e., thermogenesis, development, adipogenesis, and metabolism) were compared between sternal and retroperitoneal fat depots together with a representative skeletal muscle over the first month of postnatal life, coincident with the loss of brown fat and the accumulation of white fat. In adult sheep, implanted temperature probes were used to characterize the thermogenic response of fat and muscle to feeding and the effects of reduced or increased adiposity. UCP1 was more abundant in sternal fat than in retroperitoneal fat and was retained only in the sternal depot of adults. Distinct differences in the abundance of gene pathway markers were apparent between tissues, with sternal fat exhibiting some similarities with muscle that were not apparent in the retroperitoneal depot. In adults, the postprandial rise in temperature was greater and more prolonged in sternal fat than in retroperitoneal fat and muscle, a difference that was maintained with altered adiposity. In conclusion, sternal adipose tissue retains UCP1 into adulthood, when it shows a greater thermogenic response to feeding than do muscle and retroperitoneal fat. Sternal fat may be more amenable to targeted interventions that promote thermogenesis in large mammals.
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Affiliation(s)
- Belinda A Henry
- Metabolic Disease and Obesity Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
| | - Mark Pope
- Early Life Research Unit, Division of Child Health, Obstetrics & Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Mark Birtwistle
- Early Life Research Unit, Division of Child Health, Obstetrics & Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Rachael Loughnan
- Metabolic Disease and Obesity Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
| | - Reham Alagal
- Early Life Research Unit, Division of Child Health, Obstetrics & Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - John-Paul Fuller-Jackson
- Metabolic Disease and Obesity Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
| | - Viv Perry
- School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington LE12 5RD, United Kingdom
| | - Helen Budge
- Early Life Research Unit, Division of Child Health, Obstetrics & Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Iain J Clarke
- Neuroscience Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
| | - Michael E Symonds
- Early Life Research Unit, Division of Child Health, Obstetrics & Gynaecology, School of Medicine, University of Nottingham, Nottingham NG7 2UH, United Kingdom
- Nottingham Digestive Disease Centre and Biomedical Research Unit, School of Medicine, Queen's Medical Centre, The University of Nottingham, Nottingham NG7 2UH, United Kingdom
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AMP-Activated Kinase (AMPK) Activation by AICAR in Human White Adipocytes Derived from Pericardial White Adipose Tissue Stem Cells Induces a Partial Beige-Like Phenotype. PLoS One 2016; 11:e0157644. [PMID: 27322180 PMCID: PMC4913939 DOI: 10.1371/journal.pone.0157644] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 06/02/2016] [Indexed: 12/23/2022] Open
Abstract
Beige adipocytes are special cells situated in the white adipose tissue. Beige adipocytes, lacking thermogenic cues, morphologically look quite similar to regular white adipocytes, but with a markedly different response to adrenalin. White adipocytes respond to adrenergic stimuli by enhancing lipolysis, while in beige adipocytes adrenalin induces mitochondrial biogenesis too. A key step in the differentiation and function of beige adipocytes is the deacetylation of peroxisome proliferator-activated receptor (PPARγ) by SIRT1 and the consequent mitochondrial biogenesis. AMP-activated protein kinase (AMPK) is an upstream activator of SIRT1, therefore we set out to investigate the role of AMPK in beige adipocyte differentiation using human adipose-derived mesenchymal stem cells (hADMSCs) from pericardial adipose tissue. hADMSCs were differentiated to white and beige adipocytes and the differentiation medium of the white adipocytes was supplemented with 100 μM [(2R,3S,4R,5R)-5-(4-Carbamoyl-5-aminoimidazol-1-yl)-3,4-dihydroxyoxolan-2-yl]methyl dihydrogen phosphate (AICAR), a known activator of AMPK. The activation of AMPK with AICAR led to the appearance of beige-like morphological properties in differentiated white adipocytes. Namely, smaller lipid droplets appeared in AICAR-treated white adipocytes in a similar fashion as in beige cells. Moreover, in AICAR-treated white adipocytes the mitochondrial network was more fused than in white adipocytes; a fused mitochondrial system was characteristic to beige adipocytes. Despite the morphological similarities between AICAR-treated white adipocytes and beige cells, functionally AICAR-treated white adipocytes were similar to white adipocytes. We were unable to detect increases in basal or cAMP-induced oxygen consumption rate (a marker of mitochondrial biogenesis) when comparing control and AICAR-treated white adipocytes. Similarly, markers of beige adipocytes such as TBX1, UCP1, CIDEA, PRDM16 and TMEM26 remained the same when comparing control and AICAR-treated white adipocytes. Our data point out that in human pericardial hADMSCs the role of AMPK activation in controlling beige differentiation is restricted to morphological features, but not to actual metabolic changes.
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Maurer SF, Fromme T, Grossman LI, Hüttemann M, Klingenspor M. The brown and brite adipocyte marker Cox7a1 is not required for non-shivering thermogenesis in mice. Sci Rep 2015; 5:17704. [PMID: 26635001 PMCID: PMC4669493 DOI: 10.1038/srep17704] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 11/03/2015] [Indexed: 12/11/2022] Open
Abstract
The cytochrome c oxidase subunit isoform Cox7a1 is highly abundant in skeletal muscle and heart and influences enzyme activity in these tissues characterised by high oxidative capacity. We identified Cox7a1, well-known as brown adipocyte marker gene, as a cold-responsive protein of brown adipose tissue. We hypothesised a mechanistic relationship between cytochrome c oxidase activity and Cox7a1 protein levels affecting the oxidative capacity of brown adipose tissue and thus non-shivering thermogenesis. We subjected wildtype and Cox7a1 knockout mice to different temperature regimens and tested characteristics of brown adipose tissue activation. Cytochrome c oxidase activity, uncoupling protein 1 expression and maximal norepinephrine-induced heat production were gradually increased during cold-acclimation, but unaffected by Cox7a1 knockout. Moreover, the abundance of uncoupling protein 1 competent brite cells in white adipose tissue was not influenced by presence or absence of Cox7a1. Skin temperature in the interscapular region of neonates was lower in uncoupling protein 1 knockout pups employed as a positive control, but not in Cox7a1 knockout pups. Body mass gain and glucose tolerance did not differ between wildtype and Cox7a1 knockout mice fed with high fat or control diet. We conclude that brown adipose tissue function in mice does not require the presence of Cox7a1.
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Affiliation(s)
- Stefanie F Maurer
- Chair of Molecular Nutritional Medicine, Technische Universität München, Else Kröner-Fresenius Center for Nutritional Medicine &ZIEL-Institute for Food and Health, 85350 Freising-Weihenstephan, Germany
| | - Tobias Fromme
- Chair of Molecular Nutritional Medicine, Technische Universität München, Else Kröner-Fresenius Center for Nutritional Medicine &ZIEL-Institute for Food and Health, 85350 Freising-Weihenstephan, Germany
| | - Lawrence I Grossman
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Martin Klingenspor
- Chair of Molecular Nutritional Medicine, Technische Universität München, Else Kröner-Fresenius Center for Nutritional Medicine &ZIEL-Institute for Food and Health, 85350 Freising-Weihenstephan, Germany
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