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Münzberg H, Heymsfield SB, Berthoud HR, Morrison CD. History and future of leptin: Discovery, regulation and signaling. Metabolism 2024; 161:156026. [PMID: 39245434 DOI: 10.1016/j.metabol.2024.156026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 08/27/2024] [Accepted: 09/04/2024] [Indexed: 09/10/2024]
Abstract
The cloning of leptin 30 years ago in 1994 was an important milestone in obesity research. Prior to the discovery of leptin, obesity was stigmatized as a condition caused by lack of character and self-control. Mutations in either leptin or its receptor were the first single gene mutations found to cause severe obesity, and it is now recognized that obesity is caused mostly by a dysregulation of central neuronal circuits. Since the discovery of the leptin-deficient obese mouse (ob/ob) the cloning of leptin (ob aka lep) and leptin receptor (db aka lepr) genes, we have learned much about leptin and its action in the central nervous system. The first hope that leptin would cure obesity was quickly dampened because humans with obesity have increased leptin levels and develop leptin resistance. Nevertheless, leptin target sites in the brain represent an excellent blueprint to understand how neuronal circuits control energy homeostasis. Our expanding understanding of leptin function, interconnection of leptin signaling with other systems and impact on distinct physiological functions continues to guide and improve the development of safe and effective interventions to treat metabolic illnesses. This review highlights past concepts and current emerging concepts of the hormone leptin, leptin receptor signaling pathways and central targets to mediate distinct physiological functions.
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Affiliation(s)
- Heike Münzberg
- Pennington Biomedical Research Center, LSU System, Baton Rouge, LA, United States of America.
| | - Steven B Heymsfield
- Pennington Biomedical Research Center, LSU System, Baton Rouge, LA, United States of America
| | - Hans-Rudolf Berthoud
- Pennington Biomedical Research Center, LSU System, Baton Rouge, LA, United States of America
| | - Christopher D Morrison
- Pennington Biomedical Research Center, LSU System, Baton Rouge, LA, United States of America
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de Sousa É, de Mendonça M, Bolin AP, de Oliveira NP, Real CC, Hu X, Huang ZP, Wang DZ, Rodrigues AC. Sex-specific regulation of miR-22 and ERα in white adipose tissue of obese dam's female offspring impairs the early postnatal development of functional beige adipocytes in mice. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167057. [PMID: 38331111 DOI: 10.1016/j.bbadis.2024.167057] [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: 07/07/2023] [Revised: 12/31/2023] [Accepted: 01/30/2024] [Indexed: 02/10/2024]
Abstract
During inguinal adipose tissue (iWAT) ontogenesis, beige adipocytes spontaneously appear between postnatal 10 (P10) and P20 and their ablation impairs iWAT browning capacity in adulthood. Since maternal obesity has deleterious effects on offspring iWAT function, we aimed to investigate its effect in spontaneous iWAT browning in offspring. Female C57BL/6 J mice were fed a control or obesogenic diet six weeks before mating. Male and female offspring were euthanized at P10 and P20 or weaned at P21 and fed chow diet until P60. At P50, mice were treated with saline or CL316,243, a β3-adrenoceptor agonist, for ten days. Maternal obesity induced insulin resistance at P60, and CL316,243 treatment effectively restored insulin sensitivity in male but not female offspring. This discrepancy occurred due to female offspring severe browning impairment. During development, the spontaneous iWAT browning and sympathetic nerve branching at P20 were severely impaired in female obese dam's offspring but occurred normally in males. Additionally, maternal obesity increased miR-22 expression in the iWAT of male and female offspring during development. ERα, a target and regulator of miR-22, was concomitantly upregulated in the male's iWAT. Next, we evaluated miR-22 knockout (KO) offspring at P10 and P20. The miR-22 deficiency does not affect spontaneous iWAT browning in females and, surprisingly, anticipates iWAT browning in males. In conclusion, maternal obesity impairs functional iWAT development in the offspring in a sex-specific way that seems to be driven by miR-22 levels and ERα signaling. This impacts adult browning capacity and glucose homeostasis, especially in female offspring.
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Affiliation(s)
- Érica de Sousa
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Mariana de Mendonça
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Anaysa Paola Bolin
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Nayara Preste de Oliveira
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | | | - Xiaoyun Hu
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Zhan-Peng Huang
- Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Da-Zhi Wang
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Alice Cristina Rodrigues
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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Cheng J, Luo Y, Yang L, Li Y, Zhang F, Zhang X, Zhou X, Ji L. The association between living altitude and serum leptin concentrations in native women. Front Endocrinol (Lausanne) 2023; 14:1107932. [PMID: 36909317 PMCID: PMC9992867 DOI: 10.3389/fendo.2023.1107932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/08/2023] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND Lower diabetes prevalence and cardiovascular mortality have been observed in residents at a higher altitude. Leptin is associated with incident diabetes and adverse cardiovascular outcomes, and our aim was to investigate the association of living altitude with serum leptin concentrations. METHODS Two cross-sectional surveys were used in this study, including native populations living at Tibet (high altitude) and Beijing (low altitude). A propensity score was conducted for matching age and body mass index (BMI) between native women at high and low altitude. Pearson's correlation analysis was performed to evaluate the correlation of leptin with other variables. RESULTS A total of 1414 native women were included in this study, including 594 at high altitude and 820 at low altitude. The serum leptin concentrations of native women living at high altitude were 13.74 ± 11.03 ng/ml, which was significantly lower than that of native women living at low altitude (20.90 ± 12.91 ng/ml). After matching age and BMI, women living at the high altitude still had lower serum leptin concentrations. After adjusting for the potential confounding factors, the correlation coefficient between Ln (leptin) and BMI of women at high altitude was significantly lower than that of women at low altitude (0.228 versus 0.559; P <0.0001). The serum leptin concentrations of each BMI subgroup (<18.5, 18.5 to <25, 25 to <30, ≥ 30 kg/m2) in women at high altitude were lower than that in women at low altitude. CONCLUSIONS Serum leptin concentrations were significantly decreased in native women living at high altitude, and living altitude may alter the correlation of BMI and leptin. The findings of our study support that residents at high altitude have a protective effect with regards to improving cardiovascular and metabolic outcomes.
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Affiliation(s)
- Jiayu Cheng
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
| | - Yingying Luo
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
| | - Lihui Yang
- Department of Endocrinology and Metabolism, Tibet Autonomous Region People’s Hospital, Lasah, China
| | - Yufeng Li
- Department of Endocrinology and Metabolism, Capital Medical University Pinggu Teaching Hospital, Beijing, China
| | - Fang Zhang
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
| | - Xiuying Zhang
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
| | - Xianghai Zhou
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
- *Correspondence: Xianghai Zhou, ; Linong Ji,
| | - Linong Ji
- Department of Endocrinology and Metabolism, Peking University People’s Hospital, Beijing, China
- *Correspondence: Xianghai Zhou, ; Linong Ji,
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Different Changes in Adipokines, Lipid Profile, and TNF-Alpha Levels between 10 and 20 Whole Body Cryostimulation Sessions in Individuals with I and II Degrees of Obesity. Biomedicines 2022; 10:biomedicines10020269. [PMID: 35203477 PMCID: PMC8869184 DOI: 10.3390/biomedicines10020269] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/16/2022] [Accepted: 01/20/2022] [Indexed: 02/07/2023] Open
Abstract
Obesity is associated with chronic inflammation. While cold therapy influences the pro/antioxidative status of an individual, by affecting adipokine levels and the lipid profile, the effect of body mass index (BMI) on the response to cold exposure is unclear. We analyzed the link between BMI and the differences in effects of whole-body stimulation, depending on the number of treatments, on specific physiological parameters in men. Twenty-seven non-active men were divided into three groups: N (n = 9, BMI < 24.9), IOb (n = 9, BMI 30.0–34.9), and IIOb (BMI ≥ 35.0). The subjects participated in 20 3-min cryochamber sessions (−120 °C), 1/day, 5 days/week. Body composition was analyzed before and after treatment. Blood adiponectin (ADP), leptin (LEP), and tumor necrosis factor alpha (TNF-alpha) levels, and the lipid profile were analyzed three times: at baseline and up to 2 h after 10 and 20 sessions. The 20 treatments caused significant changes in body composition. Between 10 and 20 whole-body cryostimulation (WBC) sessions, a significant decreased was observed in the LEP and TNF-alpha levels. No significant changes in the lipid profile were noted. However, a positive tendency to regain the metabolic balance in adipose tissue was apparent in the IOb group in the tested period (decreased TG levels, increased HDL levels or the HDL/LDL ratio, and significantly decreased visceral adiposity index levels). Collectively, for people with obesity increasing the number of treatments above the standard 10 should be recommended.
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Knezevic S, Ghafoor A, Mehri S, Barazi A, Dziura M, Trant JF, Dieni CA. Catechin and other catechol-containing secondary metabolites: Bacterial biotransformation and regulation of carbohydrate metabolism. PHARMANUTRITION 2021. [DOI: 10.1016/j.phanu.2021.100273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Saeidi A, Haghighi MM, Kolahdouzi S, Daraei A, Abderrahmane AB, Essop MF, Laher I, Hackney AC, Zouhal H. The effects of physical activity on adipokines in individuals with overweight/obesity across the lifespan: A narrative review. Obes Rev 2021; 22:e13090. [PMID: 32662238 DOI: 10.1111/obr.13090] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/05/2020] [Accepted: 06/12/2020] [Indexed: 12/14/2022]
Abstract
This narrative review summarizes current knowledge on the effects of physical activity (PA) on adipokine levels in individuals with overweight and obesity. Approximately 90 investigations including randomized control, cross-sectional and longitudinal studies that reported on the effects of a single session of PA (acute) or long-term PA (chronic) on adipokine levels in individuals with overweight/obesity were reviewed. The findings support the notion that there is consensus on the benefits of chronic exercise training-regardless of the mode (resistance vs. aerobic), intensity and cohort (healthy vs. diabetes)-on adipokine levels (such as tumour necrosis factor-alpha, interleukin-6, adiponectin, visfatin, omentin-1 and leptin). However, several confounding factors (frequency, intensity, time and type of exercise) can alter the magnitude of the effects of an acute exercise session. Available evidence suggests that PA, as a part of routine lifestyle behaviour, improves obesity complications by modulating adipokine levels. However, additional research is needed to help identify the most effective interventions to elicit the most beneficial changes in adipokine levels in individuals with overweight/obesity.
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Affiliation(s)
- Ayoub Saeidi
- Department of Physical Education, Damghan Branch, Islamic Azad University, Damghan, Iran
| | - Marjan Mosalman Haghighi
- Faculty of Medicine and Health, Cardiology Centre, The University of Sydney, The Children's Hospital at Westmead, Sydney, Australia
| | - Sarkawt Kolahdouzi
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Mazandaran, Babolsar, Iran
| | - Ali Daraei
- Department of Biological Sciences in Sport, Faculty of Sports Sciences and Health, Shahid Beheshti University, Tehran, Iran
| | | | - M Faadiel Essop
- Centre for Cardio-metabolic Research in Africa (CARMA), Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Ismail Laher
- Department of Anesthesiology, Pharmacology and Therapeutics, The University of British Columbia, Vancouver, Canada
| | - Anthony C Hackney
- Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, NC, USA
| | - Hassane Zouhal
- Movement, Sport and Health Sciences Laboratory (M2S), UFR-STAPS, University of Rennes 2-ENS Rennes, Rennes, France
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Poetsch MS, Strano A, Guan K. Role of Leptin in Cardiovascular Diseases. Front Endocrinol (Lausanne) 2020; 11:354. [PMID: 32655492 PMCID: PMC7325922 DOI: 10.3389/fendo.2020.00354] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/06/2020] [Indexed: 01/01/2023] Open
Abstract
The adipocyte-derived adipokine leptin exerts pleiotropic effects, which are essential for the regulation of energy balance and cell metabolism, for controlling inflammatory and immune responses, and for the maintenance of homeostasis of the cardiovascular system. Leptin resistance in obese or type 2 diabetes mellitus (T2DM) patients is defined as a decrease in tissue response to leptin. In the cardiovascular system, leptin resistance exhibits the adverse effect on the heart's response to stress conditions and promoting cardiac remodeling due to impaired cardiac metabolism, increased fibrosis, vascular dysfunction, and enhanced inflammation. Leptin resistance or leptin signaling deficiency results in the risk increase of cardiac dysfunction and heart failure, which is a leading cause of obesity- and T2DM-related morbidity and mortality. Animal studies using leptin- and leptin receptor- (Lepr) deficient rodents have provided many useful insights into the underlying molecular and pathophysiological mechanisms of obese- and T2DM-associated metabolic and cardiovascular diseases. However, none of the animal models used so far can fully recapitulate the phenotypes of patients with obese or T2DM. Therefore, the role of leptin in the human cardiovascular system, and whether leptin affects cardiac function directly or acts through a leptin-regulated neurohumoral pathway, remain elusive. As the prevalence of obesity and diabetes is continuously increasing, strategies are needed to develop and apply human cell-based models to better understand the precise role of leptin directly in different cardiac cell types and to overcome the existing translational barriers. The purpose of this review is to discuss the mechanisms associated with leptin signaling deficiency or leptin resistance in the development of metabolic and cardiovascular diseases. We analyzed and comprehensively addressed substantial findings in pathophysiological mechanisms in commonly used leptin- or Lepr-deficient rodent models and highlighted the differences between rodents and humans. This may open up new strategies to develop directly and reliably applicable models, which resemble the human pathophysiology in order to advance health care management of obesity- and T2DM-related cardiovascular complications.
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Gioldasi S, Karvela A, Rojas-Gil AP, Rodi M, de Lastic AL, Thomas I, Spiliotis BE, Mouzaki A. Metabolic Association between Leptin and the Corticotropin Releasing Hormone. Endocr Metab Immune Disord Drug Targets 2020; 19:458-466. [PMID: 30727936 PMCID: PMC7360915 DOI: 10.2174/1871530319666190206165626] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 10/31/2018] [Accepted: 12/27/2018] [Indexed: 01/29/2023]
Abstract
Objective In healthy individuals, leptin is produced from adipose tissue and is secreted into the circulation to communicate energy balance status to the brain and control fat metabolism. Corticotropin-Releasing Hormone (CRH) is synthesized in the hypothalamus and regulates stress responses. Among the many adipokines and hormones that control fat metabolism, leptin and CRH both curb appetite and inhibit food intake. Despite numerous reports on leptin and CRH properties and function, little has been actually shown about their association in the adipose tissue environment. Methods In this article, we summarized the salient information on leptin and CRH in relation to metabolism. We also investigated the direct effect of recombinant CRH on leptin secretion by primary cultures of human adipocytes isolated from subcutaneous abdominal adipose tissue of 7 healthy children and adolescents, and measured CRH and leptin levels in plasma collected from peripheral blood of 24 healthy children and adolescents to assess whether a correlation exists between CRH and leptin levels in the periphery. Results and Conclusion The available data indicate that CRH exerts a role in the regulation of leptin in human adipocytes. We show that CRH downregulates leptin production by mature adipocytes and that a strong negative correlation exists between CRH and leptin levels in the periphery, and suggest the possible mechanisms of CRH control of leptin. Delineation of CRH control of leptin production by adipocytes may explain unknown pathogenic mechanisms linking stress and metabolism.
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Affiliation(s)
- Sofia Gioldasi
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Alexia Karvela
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Medical School, University of Patras, Patras, Greece
| | | | - Maria Rodi
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Anne-Lise de Lastic
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Iason Thomas
- Department of Allergy, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Bessie E Spiliotis
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Medical School, University of Patras, Patras, Greece
| | - Athanasia Mouzaki
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
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The Novel Perspectives of Adipokines on Brain Health. Int J Mol Sci 2019; 20:ijms20225638. [PMID: 31718027 PMCID: PMC6887733 DOI: 10.3390/ijms20225638] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/05/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022] Open
Abstract
First seen as a fat-storage tissue, the adipose tissue is considered as a critical player in the endocrine system. Precisely, adipose tissue can produce an array of bioactive factors, including cytokines, lipids, and extracellular vesicles, which target various systemic organ systems to regulate metabolism, homeostasis, and immune response. The global effects of adipokines on metabolic events are well defined, but their impacts on brain function and pathology remain poorly defined. Receptors of adipokines are widely expressed in the brain. Mounting evidence has shown that leptin and adiponectin can cross the blood–brain barrier, while evidence for newly identified adipokines is limited. Significantly, adipocyte secretion is liable to nutritional and metabolic states, where defective circuitry, impaired neuroplasticity, and elevated neuroinflammation are symptomatic. Essentially, neurotrophic and anti-inflammatory properties of adipokines underlie their neuroprotective roles in neurodegenerative diseases. Besides, adipocyte-secreted lipids in the bloodstream can act endocrine on the distant organs. In this article, we have reviewed five adipokines (leptin, adiponectin, chemerin, apelin, visfatin) and two lipokines (palmitoleic acid and lysophosphatidic acid) on their roles involving in eating behavior, neurotrophic and neuroprotective factors in the brain. Understanding and regulating these adipokines can lead to novel therapeutic strategies to counteract metabolic associated eating disorders and neurodegenerative diseases, thus promote brain health.
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Caron A, Reynolds RP, Castorena CM, Michael NJ, Lee CE, Lee S, Berdeaux R, Scherer PE, Elmquist JK. Adipocyte Gs but not Gi signaling regulates whole-body glucose homeostasis. Mol Metab 2019; 27:11-21. [PMID: 31279640 PMCID: PMC6717754 DOI: 10.1016/j.molmet.2019.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/20/2019] [Accepted: 06/20/2019] [Indexed: 01/24/2023] Open
Abstract
Objective The sympathetic nervous system (SNS) is a key regulator of the metabolic and endocrine functions of adipose tissue. Increased SNS outflow promotes fat mobilization, stimulates non-shivering thermogenesis, promotes browning, and inhibits leptin production. Most of these effects are attributed to norepinephrine activation of the Gs-coupled beta adrenergic receptors located on the surface of the adipocytes. Evidence suggests that other adrenergic receptor subtypes, including the Gi-coupled alpha 2 adrenergic receptors might also mediate the SNS effects on adipose tissue. However, the impact of acute stimulation of adipocyte Gs and Gi has never been reported. Methods We harness the power of chemogenetics to develop unique mouse models allowing the specific and spatiotemporal stimulation of adipose tissue Gi and Gs signaling. We evaluated the impact of chemogenetic stimulation of these pathways on glucose homeostasis, lipolysis, leptin production, and gene expression. Results Stimulation of Gs signaling in adipocytes induced rapid and sustained hypoglycemia. These hypoglycemic effects were secondary to increased insulin release, likely consequent to increased lipolysis. Notably, we also observed differences in gene regulation and ex vivo lipolysis in different adipose depots. In contrast, acute stimulation of Gi signaling in adipose tissue did not affect glucose metabolism or lipolysis, but regulated leptin production. Conclusion Our data highlight the significance of adipose Gs signaling in regulating systemic glucose homeostasis. We also found previously unappreciated heterogeneity across adipose depots following acute stimulation. Together, these results highlight the complex interactions of GPCR signaling in adipose tissue and demonstrate the usefulness of chemogenetic technology to better understand adipocyte function. Chemogenetic stimulation of Gs signaling in adipose tissue potently induces hypoglycemia in mice. The magnitude by which adipose Gs stimulation reduces blood glucose is similar to the hypoglycemic effects of insulin. Chemogenetic stimulation of Gs signaling in adipose tissue ex vivo stimulates lipolysis. Chemogenetic stimulation of adipose Gi signaling does not affect glycemia or lipolysis, but increases leptin levels. Our data demonstrate the usefulness of chemogenetic technology to understand adipocytes functions.
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Affiliation(s)
- Alexandre Caron
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Ryan P Reynolds
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Carlos M Castorena
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Natalie J Michael
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Charlotte E Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Syann Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rebecca Berdeaux
- Department of Integrative Biology and Pharmacology, Center for Metabolic and Degenerative Diseases at the Brown Foundation, Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Graduate Program in Biochemistry and Cell Biology, MD Anderson Cancer Center-UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joel K Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Abstract
Perivascular adipose tissue (PVAT) refers to the local aggregate of adipose tissue surrounding the vascular tree, exhibiting phenotypes from white to brown and beige adipocytes. Although PVAT has long been regarded as simply a structural unit providing mechanical support to vasculature, it is now gaining reputation as an integral endocrine/paracrine component, in addition to the well-established modulator endothelium, in regulating vascular tone. Since the discovery of anti-contractile effect of PVAT in 1991, the use of multiple rodent models of reduced amounts of PVAT has revealed its regulatory role in vascular remodeling and cardiovascular implications, including atherosclerosis. PVAT does not only release PVAT-derived relaxing factors (PVRFs) to activate multiple subsets of endothelial and vascular smooth muscle potassium channels and anti-inflammatory signals in the vasculature, but it does also provide an interface for neuron-adipocyte interactions in the vascular wall to regulate arterial vascular tone. In this review, we outline our current understanding towards PVAT and attempt to provide hints about future studies that can sharpen the therapeutic potential of PVAT against cardiovascular diseases and their complications.
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Affiliation(s)
- Chak Kwong Cheng
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China
- Institute of Vascular Medicine, Shenzhen Research Institute and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Hamidah Abu Bakar
- Health Sciences Department, Universiti Selangor, 40000, Shah Alam, Selangor, Malaysia
| | - Maik Gollasch
- Experimental and Clinical Research Center (ECRC)-a joint cooperation between the Charité-University Medicine Berlin and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13125, Berlin, Germany.
- Medical Clinic for Nephrology and Internal Intensive Care, Charité Campus Virchow Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Yu Huang
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China.
- Institute of Vascular Medicine, Shenzhen Research Institute and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China.
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Hung WC, Tsai CM, Lin CW, Chuang CY, Yang SF, Weng CJ. Leptin -2548 G/A polymorphisms are associated to clinical progression of oral cancer and sensitive to oral tumorization in nonsmoking population. J Cell Biochem 2019; 120:15145-15156. [PMID: 31021458 DOI: 10.1002/jcb.28776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/09/2019] [Accepted: 01/14/2019] [Indexed: 11/06/2022]
Abstract
Oral cancer is causally associated with environmental carcinogens, and the susceptibility to carcinogen-mediated tumorigenesis is proposed to be genotype-dependent. Leptin (LEP) and leptin receptor (LEPR) both play a crucial role in the mediation of physiological reactions and carcinogenesis and may serve as a candidate biomarker of oral cancer. The current case-control study aimed to examine the effects of LEP -2548 G/A (rs7799039), LEPR K109R (rs1137100), and LEPR Q223R (rs1137101) single-nucleotide polymorphisms (SNPs) with or without interacting to environmental carcinogens on the risk for oral squamous cell carcinoma. The SNPs of three genetic allele, from 567 patients with oral cancer and 560 healthy controls in Taiwan were analyzed. The results shown that the patients with polymorphic allele of LEP -2548 have a significant low risk for the development of clinical stage (A/G: adjusted odds ratio [AOR] = 0.670, 95% confidence interval [CI] = 0.454-0.988, P < 0.05; A/G + G/G: AOR = 0.676, 95% CI = 0.467-0.978, P < 0.05) compared to patients with ancestral homozygous A/A genotype. In addition, an interesting result was found that the impact of LEP -2548 G/A SNP on oral carcinogenesis in subjects without tobacco consumption is higher than subjects with tobacco consumption. These results suggest that the genetic polymorphism of LEP -2548 G/A (rs7799039), LEPR K109R (rs1137100), and LEPR Q223R (rs1137101) were not associated to the susceptibility of oral cancer; SNP in LEP -2548 G/A showed a poor clinicopathological development of oral cancer; population without tobacco consumption and with polymorphic LEP -2548 G/A gene may significantly increase the risk to have oral cancer.
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Affiliation(s)
- Wei-Chen Hung
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Chiung-Man Tsai
- Chest Hospital, Ministry of Health and Welfare, Tainan, Taiwan
| | - Chiao-Wen Lin
- Institute of Oral Sciences, Chung Shan Medical University, Taichung, Taiwan.,Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Chun-Yi Chuang
- School of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Shun-Fa Yang
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Chia-Jui Weng
- Department of Living Services Industry, Tainan University of Technology, Tainan, Taiwan
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Evans BA, Merlin J, Bengtsson T, Hutchinson DS. Adrenoceptors in white, brown, and brite adipocytes. Br J Pharmacol 2019; 176:2416-2432. [PMID: 30801689 DOI: 10.1111/bph.14631] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 01/28/2019] [Accepted: 02/11/2019] [Indexed: 01/01/2023] Open
Abstract
Adrenoceptors play an important role in adipose tissue biology and physiology that includes regulating the synthesis and storage of triglycerides (lipogenesis), the breakdown of stored triglycerides (lipolysis), thermogenesis (heat production), glucose metabolism, and the secretion of adipocyte-derived hormones that can control whole-body energy homeostasis. These processes are regulated by the sympathetic nervous system through actions at different adrenoceptor subtypes expressed in adipose tissue depots. In this review, we have highlighted the role of adrenoceptor subtypes in white, brown, and brite adipocytes in both rodents and humans and have included detailed analysis of adrenoceptor expression in human adipose tissue and clonally derived adipocytes. We discuss important considerations when investigating adrenoceptor function in adipose tissue or adipocytes. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.
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Affiliation(s)
- Bronwyn A Evans
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Jon Merlin
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Tore Bengtsson
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, Stockholm, Sweden
| | - Dana S Hutchinson
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
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14
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van Iersel L, Brokke KE, Adan RAH, Bulthuis LCM, van den Akker ELT, van Santen HM. Pathophysiology and Individualized Treatment of Hypothalamic Obesity Following Craniopharyngioma and Other Suprasellar Tumors: A Systematic Review. Endocr Rev 2019; 40:193-235. [PMID: 30247642 DOI: 10.1210/er.2018-00017] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 06/25/2018] [Indexed: 12/26/2022]
Abstract
The development of hypothalamic obesity (HO) following craniopharyngioma (CP) and other suprasellar tumors leads to reduced patient quality of life. No treatment algorithms are currently available for management of HO. Depending on which hypothalamic nuclei are destroyed, the pathophysiologic mechanisms and clinical symptoms that contribute to HO differ among patients. Herein, we review the contribution of the hypothalamus to the pathophysiologic mechanisms and symptoms underlying CP-associated HO. Additionally, we performed a systematic search of MEDLINE and Embase to identify all intervention studies for weight management in patients with CP or other suprasellar tumors published until September 2017. The search yielded 1866 publications, of which 40 were included. Of these 40 studies, we identified four modalities for intervention (i.e., lifestyle, dietary, pharmacotherapeutic, or surgical) within six clinical domains (i.e., psychosocial disorders, hyperphagia, sleep disturbances, decreased energy expenditure, hyperinsulinemia, and hypopituitarism). We used the findings from our systematic review, in addition to current knowledge on the pathophysiology of HO, to develop an evidence-based treatment algorithm for patients with HO caused by CP or other suprasellar tumors. Although the individual effects of the HO interventions were modest, beneficial individual effects may be achieved when the pathophysiologic background and correct clinical domain are considered. These two aspects can be combined in an individualized treatment algorithm with a stepwise approach for each clinical domain. Recently elucidated targets for HO intervention were also explored to improve future management of HO for patients with CP and other suprasellar tumors.
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Affiliation(s)
- Laura van Iersel
- Department of Pediatric Endocrinology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, Netherlands
| | - Karen E Brokke
- Medical Sciences, University Medical Center Utrecht, University of Utrecht, Utrecht, Netherlands
| | - Roger A H Adan
- Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, Netherlands.,Institute for Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lauren C M Bulthuis
- Medical Sciences, University Medical Center Utrecht, University of Utrecht, Utrecht, Netherlands
| | - Erica L T van den Akker
- Department of Pediatric Endocrinology, Erasmus MC-Sophia Children's Hospital, Rotterdam, Netherlands
| | - Hanneke M van Santen
- Department of Pediatric Endocrinology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, Netherlands
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15
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Singh R, Bansal Y, Medhi B, Kuhad A. Antipsychotics-induced metabolic alterations: Recounting the mechanistic insights, therapeutic targets and pharmacological alternatives. Eur J Pharmacol 2018; 844:231-240. [PMID: 30529195 DOI: 10.1016/j.ejphar.2018.12.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 12/02/2018] [Accepted: 12/05/2018] [Indexed: 12/14/2022]
Abstract
Atypical antipsychotics (AAPs) are the drug of choice in the management of mental illnesses by virtue of their advantage over typical antipsychotics i.e. least tendency of producing extrapyramidal motor symptoms (EPS) or pseudoparkinsonism. Despite the clinical efficacy, AAPs produces troublesome adverse effects, particularly hyperphagia, hyperglycemia, dyslipidemia weight gain, diabetes mellitus, insulin resistance and QT prolongation which further develops metabolic and cardiac complications with subsequent reduction in life expectancy, poor patient compliance, and sudden death. AAPs-induced weight gain and metabolic alterations are increasing at an alarming rate and became an utmost matter of concern for psychopharmacotherapy. Diverse underlying mechanisms have been explored such as the interaction of AAPs with neurotransmitter receptors, alteration in food reward anticipation behavior, altered expressions of hypothalamic orexigenic and anorexigenic neuropeptides, histamine H1 receptor-mediated hypothalamic AMP-activated protein kinase (AMPK) activation, increased blood leptin, ghrelin, pro-inflammatory cytokines. Antipsychotics induced imbalance in energy homeostasis, reduction in energy expenditure which is linked to altered expression of uncoupling proteins (UCP-1) in brown adipose tissue and reduced hypothalamic orexin expressions are emerging insights. In addition, alteration in gut-microbiota and subsequent inflammation, dyslipidemia, obesity, and diabetes after AAPs treatment are also associated with weight gain and metabolic alterations. Oral hypoglycemics and lipid-lowering drugs are mainly prescribed in the clinical management of weight gain associated with AAPs while many other pharmacological and nonpharmacological interventions also have been explored in different clinical and preclinical studies. In this review, we critically discuss the current scenario, mechanistic insights, biomarkers, and therapeutic alternatives for metabolic alterations associated with antipsychotics.
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Affiliation(s)
- Raghunath Singh
- Pharmacology Research Laboratory, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Study (UGC-CAS), Panjab University, Chandigarh 160014, India
| | - Yashika Bansal
- Pharmacology Research Laboratory, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Study (UGC-CAS), Panjab University, Chandigarh 160014, India
| | - Bikash Medhi
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India
| | - Anurag Kuhad
- Pharmacology Research Laboratory, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Study (UGC-CAS), Panjab University, Chandigarh 160014, India.
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16
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Marques-Oliveira GH, Silva TM, Lima WG, Valadares HMS, Chaves VE. Insulin as a hormone regulator of the synthesis and release of leptin by white adipose tissue. Peptides 2018; 106:49-58. [PMID: 29953915 DOI: 10.1016/j.peptides.2018.06.007] [Citation(s) in RCA: 18] [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: 03/13/2018] [Revised: 06/20/2018] [Accepted: 06/24/2018] [Indexed: 02/09/2023]
Abstract
Leptin and its receptor are widely distributed in several tissues, mainly in white adipose tissue. The serum leptin is highly correlated with body mass index in rodents and humans, being documented that leptin levels reduces in the fasting state and increase during refeeding, similarly to insulin release by pancreatic islets. Insulin appears to increase leptin mRNA and protein expression and its release by adipocytes. Some studies have suggested that insulin acts through the activation of the transcription factors: sterol regulatory element binding protein 1 (SREBP1), CCAAT enhancer binding protein-α (C/EBP-α) and specificity protein 1 (Sp1). Insulin stimulates the release of preformed and newly synthesized leptin by adipocytes through its signaling cascade. Its effects are blocked by inhibitors of the insulin signaling pathway, as well as by inhibitors of protein synthesis and agents that increase the intracellular cAMP. The literature data suggest that chronic hyperinsulinemia increases serum leptin levels in humans and rodents. In this review, we summarized the most updated knowledge on the effects of insulin on serum leptin levels, presenting the cell mechanisms that control leptin synthesis and release by the white adipose tissue.
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Affiliation(s)
| | - Thaís Marques Silva
- Laboratory of Physiology, Federal University of São João del-Rei, Divinópolis, Minas Gerais, Brazil
| | - William Gustavo Lima
- Laboratory of Physiology, Federal University of São João del-Rei, Divinópolis, Minas Gerais, Brazil
| | | | - Valéria Ernestânia Chaves
- Laboratory of Physiology, Federal University of São João del-Rei, Divinópolis, Minas Gerais, Brazil.
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17
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Lo KA, Huang S, Walet ACE, Zhang ZC, Leow MKS, Liu M, Sun L. Adipocyte Long-Noncoding RNA Transcriptome Analysis of Obese Mice Identified Lnc-Leptin, Which Regulates Leptin. Diabetes 2018. [PMID: 29519872 DOI: 10.2337/db17-0526] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Obesity induces profound transcriptome changes in adipocytes, and recent evidence suggests that long-noncoding RNAs (lncRNAs) play key roles in this process. We performed a comprehensive transcriptome study by RNA sequencing in adipocytes isolated from interscapular brown, inguinal, and epididymal white adipose tissue in diet-induced obese mice. The analysis revealed a set of obesity-dysregulated lncRNAs, many of which exhibit dynamic changes in the fed versus fasted state, potentially serving as novel molecular markers of adipose energy status. Among the most prominent lncRNAs is Lnc-leptin, which is transcribed from an enhancer region upstream of leptin (Lep). Expression of Lnc-leptin is sensitive to insulin and closely correlates to Lep expression across diverse pathophysiological conditions. Functionally, induction of Lnc-leptin is essential for adipogenesis, and its presence is required for the maintenance of Lep expression in vitro and in vivo. Direct interaction was detected between DNA loci of Lnc-leptin and Lep in mature adipocytes, which diminished upon Lnc-leptin knockdown. Our study establishes Lnc-leptin as a new regulator of Lep.
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MESH Headings
- Adipocytes, Brown/drug effects
- Adipocytes, Brown/metabolism
- Adipocytes, Brown/pathology
- Adipocytes, White/drug effects
- Adipocytes, White/metabolism
- Adipocytes, White/pathology
- Adipogenesis/drug effects
- Animals
- Base Sequence
- Biomarkers/metabolism
- Cells, Cultured
- Diet, High-Fat/adverse effects
- Energy Metabolism/drug effects
- Enhancer Elements, Genetic/drug effects
- Gene Expression Profiling
- Gene Expression Regulation/drug effects
- Gene Ontology
- Hypoglycemic Agents/pharmacology
- Insulin/pharmacology
- Leptin/agonists
- Leptin/antagonists & inhibitors
- Leptin/genetics
- Leptin/metabolism
- Male
- Mice, Inbred C57BL
- Obesity/etiology
- Obesity/metabolism
- Obesity/pathology
- RNA Interference
- RNA, Long Noncoding/antagonists & inhibitors
- RNA, Long Noncoding/chemistry
- RNA, Long Noncoding/metabolism
- RNA, Small Interfering/metabolism
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Affiliation(s)
- Kinyui Alice Lo
- Institute of Molecular and Cell Biology, Singapore
- Cardiovascular & Metabolic Disorders, Duke-NUS, Singapore
| | - Shiqi Huang
- Food Science and Technology Program, Department of Chemistry, National University of Singapore, Singapore
| | | | - Zhi-Chun Zhang
- Cardiovascular & Metabolic Disorders, Duke-NUS, Singapore
| | - Melvin Khee-Shing Leow
- Cardiovascular & Metabolic Disorders, Duke-NUS, Singapore
- Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research, Singapore
- National University Health System, Singapore
- Department of Endocrinology, Tan Tock Seng Hospital, Singapore
| | - Meihui Liu
- Food Science and Technology Program, Department of Chemistry, National University of Singapore, Singapore
| | - Lei Sun
- Institute of Molecular and Cell Biology, Singapore
- Cardiovascular & Metabolic Disorders, Duke-NUS, Singapore
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18
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Caron A, Dungan Lemko HM, Castorena CM, Fujikawa T, Lee S, Lord CC, Ahmed N, Lee CE, Holland WL, Liu C, Elmquist JK. POMC neurons expressing leptin receptors coordinate metabolic responses to fasting via suppression of leptin levels. eLife 2018. [PMID: 29528284 PMCID: PMC5866097 DOI: 10.7554/elife.33710] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Leptin is critical for energy balance, glucose homeostasis, and for metabolic and neuroendocrine adaptations to starvation. A prevalent model predicts that leptin’s actions are mediated through pro-opiomelanocortin (POMC) neurons that express leptin receptors (LEPRs). However, previous studies have used prenatal genetic manipulations, which may be subject to developmental compensation. Here, we tested the direct contribution of POMC neurons expressing LEPRs in regulating energy balance, glucose homeostasis and leptin secretion during fasting using a spatiotemporally controlled Lepr expression mouse model. We report a dissociation between leptin’s effects on glucose homeostasis versus energy balance in POMC neurons. We show that these neurons are dispensable for regulating food intake, but are required for coordinating hepatic glucose production and for the fasting-induced fall in leptin levels, independent of changes in fat mass. We also identify a role for sympathetic nervous system regulation of the inhibitory adrenergic receptor (ADRA2A) in regulating leptin production. Collectively, our findings highlight a previously unrecognized role of POMC neurons in regulating leptin levels.
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Affiliation(s)
- Alexandre Caron
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | | | - Carlos M Castorena
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Teppei Fujikawa
- Department of Cellular and Integrative Physiology, UT Health San Antonio, San Antonio, United States
| | - Syann Lee
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Caleb C Lord
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Newaz Ahmed
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Charlotte E Lee
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - William L Holland
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Chen Liu
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
| | - Joel K Elmquist
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States
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19
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Abstract
AbstractThe dip in food intake, which starts in late pregnancy and continues into early lactation, has traditionally been interpreted as a depression in intake due to physical constraints. However, the rôle of physical constraints on intake has been overemphasized, particularly in early lactation. There is mounting evidence that the presence and mobilization of body reserves in early lactation play an important rôle in regulating intake at this time.Conceptually, the dip in intake in early lactation observed when cows have access to non-limiting foods can be accounted for by assuming that the cow has a desired level of body reserves. When the cow is not compromised, the changes with time in body reserves and the dip in intake represent the normal case and provide the basis against which to assess true depressions in intake which may occur when the cow is compromised by limiting nutrition or environment.The regulation of body reserves and intake in the periparturient cow is orchestrated through nervous and hormonal signals. Likely factors that are involved in intake regulation are reproductive hormones, neuropeptides, adrenergic signals, insulin and insulin resistance and leptin. Furthermore, oxidation of NEFA in the liver may result in feedback signals that reduce intake. The relative importance of these is discussed. A better understanding of the physiological signals involved in intake regulation and their interrelations with body weight regulation may provide important indicators of the degree of compromise that periparturient cows may experience.
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20
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Abstract
Interactions between the brain and distinct adipose depots have a key role in maintaining energy balance, thereby promoting survival in response to metabolic challenges such as cold exposure and starvation. Recently, there has been renewed interest in the specific central neuronal circuits that regulate adipose depots. Here, we review anatomical, genetic and pharmacological studies on the neural regulation of adipose function, including lipolysis, non-shivering thermogenesis, browning and leptin secretion. In particular, we emphasize the role of leptin-sensitive neurons and the sympathetic nervous system in modulating the activity of brown, white and beige adipose tissues. We provide an overview of advances in the understanding of the heterogeneity of the brain regulation of adipose tissues and offer a perspective on the challenges and paradoxes that the community is facing regarding the actions of leptin on this system.
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Affiliation(s)
- Alexandre Caron
- Division of Hypothalamic Research and Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Syann Lee
- Division of Hypothalamic Research and Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joel K. Elmquist
- Division of Hypothalamic Research and Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Laurent Gautron
- Division of Hypothalamic Research and Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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21
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Ayala-Lopez N, Watts SW. New actions of an old friend: perivascular adipose tissue's adrenergic mechanisms. Br J Pharmacol 2016; 174:3454-3465. [PMID: 27813085 DOI: 10.1111/bph.13663] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/03/2016] [Accepted: 10/21/2016] [Indexed: 12/17/2022] Open
Abstract
The revolutionary discovery in 1991 by Soltis and Cassis that perivascular adipose tissue (PVAT) has an anti-contractile effect changed how we think about the vasculature. Most experiments on vascular pharmacology begin by removing the fat surrounding vessels. Thus, PVAT was thought to have a minor role in vascular function and its presence was just for structural support. The need to rethink PVAT's role was precipitated by observations that obesity carries a high cardiovascular risk and PVAT dysfunction is associated with obesity. PVAT is a vascular-adipose organ that has intimate connections with the nervous and immune system. A complex world of physiology resides in PVAT, including the presence of an 'adrenergic system' that is able to release, take up and metabolize noradrenaline. Adipocytes, stromal vascular cells and nerves within PVAT contain components that make up this adrenergic system. Some of the great strides in PVAT research came from studying adipose tissue as a whole. Adipose tissue has many roles and participates in regulating energy balance, energy stores, inflammation and thermoregulation. However, PVAT is dissimilar from non-PVAT adipose tissues. PVAT is intimately connected with the vasculature, which is what makes its role in body homeostasis unique. The adrenergic system within PVAT may be an integral link connecting the effects of obesity with the vascular dysfunction observed in obesity-associated hypertension, a condition in which the sympathetic nervous system has a significant role. This review will explore what is known about the adrenergic system in adipose tissue and PVAT, plus the translational importance of these findings. LINKED ARTICLES This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.
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Affiliation(s)
- Nadia Ayala-Lopez
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Stephanie W Watts
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
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22
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Tsubai T, Noda Y, Ito K, Nakao M, Seino Y, Oiso Y, Hamada Y. Insulin elevates leptin secretion and mRNA levels via cyclic AMP in 3T3-L1 adipocytes deprived of glucose. Heliyon 2016; 2:e00194. [PMID: 27896318 PMCID: PMC5121139 DOI: 10.1016/j.heliyon.2016.e00194] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 10/17/2016] [Accepted: 11/08/2016] [Indexed: 02/04/2023] Open
Abstract
Aims Leptin plays an important role in the pathogenesis of obesity and diabetes, yet the regulatory mechanisms of this hormone have not been fully elucidated. In this study, we aimed to clarify the roles of insulin and glucose in leptin secretion and mRNA production using inhibitors of insulin signal transduction in adipocytes cultured under glucose-free or normal conditions. Methods Differentiated 3T3-L1 adipocytes were stimulated with insulin in combination with inhibitors for phosphoinositide 3-kinase (PI3K), Akt, and phosphodiesterase 3B (PDE3B), as well as epinephrine and a cyclic AMP (cAMP) analog under glucose-free or normal conditions. After 8 h of stimulation, leptin protein levels in the media and leptin mRNA expression levels in the adipocytes were measured. Results Insulin significantly increased the secretion and mRNA levels of leptin under the depletion of glucose. Glucose augmented basal leptin secretion without insulin, while glucose nullified insulin-induced leptin mRNA upregulation. The PI3K inhibitor BEZ-235, the Akt inhibitor MK-2206, and the PDE3B inhibitor cilostazol attenuated the insulin stimulation of leptin secretion, but did not suppress the insulin-induced leptin mRNA upregulation with glucose depletion. In contrast to the glucose-free condition, insulin failed to upregulate leptin mRNA in the presence of glucose. The cAMP analog dibutyryl cAMP and epinephrine decreased both leptin secretion and mRNA regardless of glucose supplementation. Conclusion Insulin alone stimulates leptin secretion and elevates leptin mRNA levels via cAMP under the lack of glucose metabolism, while glucose is a significant and ambivalent effector on the insulin effects of leptin.
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Affiliation(s)
- Tomomi Tsubai
- College of Pharmacy, Kinjo Gakuin University; Omori 2-1723, Moriyama-ku, Nagoya 463-8521, Japan
- Division of Clinical Science and Neuropsychopharmacology, Graduate School and Faculty of Pharmacy, Meijo University; 150, Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yukihiro Noda
- Division of Clinical Science and Neuropsychopharmacology, Graduate School and Faculty of Pharmacy, Meijo University; 150, Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Kazuma Ito
- Division of Clinical Science and Neuropsychopharmacology, Graduate School and Faculty of Pharmacy, Meijo University; 150, Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Makoto Nakao
- College of Pharmacy, Kinjo Gakuin University; Omori 2-1723, Moriyama-ku, Nagoya 463-8521, Japan
| | - Yusuke Seino
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine; 65, Tsuruma-cho, Showa-ku, Nagoya 466-8560, Japan
| | - Yutaka Oiso
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine; 65, Tsuruma-cho, Showa-ku, Nagoya 466-8560, Japan
| | - Yoji Hamada
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine; 65, Tsuruma-cho, Showa-ku, Nagoya 466-8560, Japan
- Corresponding author at: Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya 466–8550, Japan.
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23
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Mixed – Lineage Protein kinases (MLKs) in inflammation, metabolism, and other disease states. Biochim Biophys Acta Mol Basis Dis 2016; 1862:1581-6. [DOI: 10.1016/j.bbadis.2016.05.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 05/26/2016] [Accepted: 05/27/2016] [Indexed: 02/06/2023]
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24
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Baghaiee B, Botelho Teixeira A, Tartibian B. Moderate aerobic exercise increases SOD-2 gene expression and decreases leptin and malondialdehyde in middle-aged men. Sci Sports 2016. [DOI: 10.1016/j.scispo.2015.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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25
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26
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Zhou H, Lei X, Benson T, Mintz J, Xu X, Harris RB, Weintraub NL, Wang X, Chen W. Berardinelli-Seip congenital lipodystrophy 2 regulates adipocyte lipolysis, browning, and energy balance in adult animals. J Lipid Res 2015; 56:1912-25. [PMID: 26269358 DOI: 10.1194/jlr.m060244] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Indexed: 11/20/2022] Open
Abstract
Mutations in BSCL2/SEIPIN cause Berardinelli-Seip congenital lipodystrophy type 2 (BSCL2), but the mechanisms whereby Bscl2 regulates adipose tissue function are unclear. Here, we generated adipose tissue (mature) Bscl2 knockout (Ad-mKO) mice, in which Bscl2 was specifically ablated in adipocytes of adult animals, to investigate the impact of acquired Bscl2 deletion on adipose tissue function and energy balance. Ad-mKO mice displayed reduced adiposity and were protected against high fat diet-induced obesity, but not insulin resistance or hepatic steatosis. Gene expression profiling and biochemical assays revealed increased lipolysis and fatty acid oxidation in white adipose tissue (WAT) and brown adipose tissue , as well as browning of WAT, owing to induction of cAMP/protein kinase A signaling upon Bscl2 deletion. Interestingly, Bscl2 deletion reduced food intake and downregulated adipose β3-adrenergic receptor (ADRB3) expression. Impaired ADRB3 signaling partially offsets upregulated browning-induced energy expenditure and thermogenesis in Ad-mKO mice housed at ambient temperature. However, this counter-regulatory response was abrogated under thermoneutral conditions, resulting in even greater body mass loss in Ad-mKO mice. These findings suggest that Bscl2 regulates adipocyte lipolysis and β-adrenergic signaling to produce complex effects on adipose tissues and whole-body energy balance.
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Affiliation(s)
- Hongyi Zhou
- Department of Physiology, Georgia Regents University, Augusta, GA 30912
| | - Xinnuo Lei
- Department of Physiology, Georgia Regents University, Augusta, GA 30912
| | - Tyler Benson
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912
| | - James Mintz
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912
| | - Xiaojing Xu
- Georgia Prevention Institute, Department of Pediatrics, Georgia Regents University, Augusta, GA 30912
| | - Ruth B Harris
- Department of Physiology, Georgia Regents University, Augusta, GA 30912
| | - Neal L Weintraub
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912
| | - Xiaoling Wang
- Georgia Prevention Institute, Department of Pediatrics, Georgia Regents University, Augusta, GA 30912
| | - Weiqin Chen
- Department of Physiology, Georgia Regents University, Augusta, GA 30912
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27
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Abstract
Stress is defined as a state that can threaten homeostasis in an organism to initiate the adaptive process. Stress mediators, which include the classic neuroendocrine hormones and a number of neurotransmitters, cytokines, and growth factors, regulate both basal and threatened homeostasis to help control the stress. Severity of stress, as well as malfunctioning of stress pathways, may impair its controllability, leading to the pathogenesis of psychiatric illnesses including depression. Leptin was initially identified as an antiobesity hormone, acting as a negative feedback adiposity signal to control energy homeostasis by binding to its receptors in the hypothalamus. Accumulating evidence has expanded the function of leptin from the control of energy balance to the regulation of other physiological and psychological processes. The aim of this paper is to evaluate the potential role of leptin in stress controllability. To this end, studies on the role of leptin in stress-induced activation of the hypothalamus-pituitary-adrenocortical axis, feeding behavior, learned helplessness, and other depression models have been accumulated. The knowledge accumulated in this article may facilitate the development of alternative treatment strategies, beyond serotonin and noradrenaline reuptake inhibition, for psychiatric care and stress-related disorders.
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Calorie restriction-mediated restoration of hypothalamic signal transducer and activator of transcription 3 (STAT3) phosphorylation is not effective for lowering the body weight set point in IRS-2 knockout obese mice. Diabetol Int 2015. [DOI: 10.1007/s13340-015-0205-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Yonekura S, Hirota S, Tokutake Y, Rose MT, Katoh K, Aso H. Dexamethasone and acetate modulate cytoplasmic leptin in bovine preadipocytes. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 27:567-73. [PMID: 25049989 PMCID: PMC4093523 DOI: 10.5713/ajas.2013.13559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 12/26/2013] [Accepted: 12/10/2013] [Indexed: 11/27/2022]
Abstract
Hormonal and nutrient signals regulate leptin synthesis and secretion. In rodents, leptin is stored in cytosolic pools of adipocytes. However, not much information is available regarding the regulation of intracellular leptin in ruminants. Recently, we demonstrated that leptin mRNA was expressed in bovine intramuscular preadipocyte cells (BIP cells) and that a cytoplasmic leptin pool may be present in preadipocytes. In the present study, we investigated the expression of cytoplasmic leptin protein in BIP cells during differentiation as well as the effects of various factors added to the differentiation medium on its expression in BIP cells. Leptin mRNA expression was observed only at 6 and 8 days after adipogenic induction, whereas the cytoplasmic leptin concentration was the highest on day 0 and decreased gradually thereafter. Cytoplasmic leptin was detected at 6 and 8 days after adipogenic induction, but not at 4 days after adipogenic induction. The cytoplasmic leptin concentration was reduced in BIP cells at 4 days after treatment with dexamethasone, whereas cytoplasmic leptin was not observed at 8 days after treatment. In contrast, acetate significantly enhanced the cytoplasmic leptin concentration in BIP cells at 8 days after treatment, although acetate alone did not induce adipocyte differentiation in BIP cells. These results suggest that dexamethasone and acetate modulate the cytoplasmic leptin concentration in bovine preadipocytes.
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Affiliation(s)
- Shinichi Yonekura
- Institute of Rural Studies, University of Wales, Aberystwyth, Ceredigion SY23 3AL, UK
| | - Shohei Hirota
- Institute of Rural Studies, University of Wales, Aberystwyth, Ceredigion SY23 3AL, UK
| | - Yukako Tokutake
- Institute of Rural Studies, University of Wales, Aberystwyth, Ceredigion SY23 3AL, UK
| | - Michael T Rose
- Institute of Rural Studies, University of Wales, Aberystwyth, Ceredigion SY23 3AL, UK
| | - Kazuo Katoh
- Department of Animal Physiology, Graduate School of Agriculture, Tohoku University, Amamiyamachi, Sendai 981-8555, Japan
| | - Hisashi Aso
- Department of Cellular Biology, Graduate School of Agriculture, Tohoku University, Amamiyamachi, Sendai 981-8555, Japan
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Harris RBS. Direct and indirect effects of leptin on adipocyte metabolism. Biochim Biophys Acta Mol Basis Dis 2013; 1842:414-23. [PMID: 23685313 DOI: 10.1016/j.bbadis.2013.05.009] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/18/2013] [Accepted: 05/06/2013] [Indexed: 12/22/2022]
Abstract
Leptin is hypothesized to function as a negative feedback signal in the regulation of energy balance. It is produced primarily by adipose tissue and circulating concentrations correlate with the size of body fat stores. Administration of exogenous leptin to normal weight, leptin responsive animals inhibits food intake and reduces the size of body fat stores whereas mice that are deficient in either leptin or functional leptin receptors are hyperphagic and obese, consistent with a role for leptin in the control of body weight. This review discusses the effect of leptin on adipocyte metabolism. Because adipocytes express leptin receptors there is the potential for leptin to influence adipocyte metabolism directly. Adipocytes also are insulin responsive and receive sympathetic innervation, therefore leptin can also modify adipocyte metabolism indirectly. Studies published to date suggest that direct activation of adipocyte leptin receptors has little effect on cell metabolism in vivo, but that leptin modifies adipocyte sensitivity to insulin to inhibit lipid accumulation. In vivo administration of leptin leads to a suppression of lipogenesis, an increase in triglyceride hydrolysis and an increase in fatty acid and glucose oxidation. Activation of central leptin receptors also contributes to the development of a catabolic state in adipocytes, but this may vary between different fat depots. Leptin reduces the size of white fat depots by inhibiting cell proliferation both through induction of inhibitory circulating factors and by contributing to sympathetic tone which suppresses adipocyte proliferation. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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Affiliation(s)
- Ruth B S Harris
- Department of Physiology, Medical College of Georgia, Georgia Regents University, USA.
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Koupenova M, Ravid K. Adenosine, adenosine receptors and their role in glucose homeostasis and lipid metabolism. J Cell Physiol 2013; 228:1703-1712. [PMID: 23460239 PMCID: PMC3849123 DOI: 10.1002/jcp.24352] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Revised: 02/09/2013] [Accepted: 02/12/2013] [Indexed: 01/12/2023]
Abstract
Adenosine is an endogenous metabolite that is released from all tissues and cells including liver, pancreas, muscle and fat, particularly under stress, intense exercise, or during cell damage. The role of adenosine in glucose homeostasis has been attributed to its ability to regulate, through its membrane receptors, processes such as insulin secretion, glucose release and clearance, glycogenolysis, and glycogenesis. Additionally, adenosine and its multiple receptors have been connected to lipid metabolism by augmenting insulin-mediated inhibition of lipolysis, and the subsequent increase in free fatty acids and glycerol levels. Furthermore, adenosine was reported to control liver cholesterol synthesis, consequently affecting plasma levels of cholesterol and triglycerides, and the amount of fat tissue. Alterations in the balance of glucose and lipid homeostasis have implications in both cardiovascular disease and diabetes. The ability of different adenosine receptors to activate and inhibit the same signaling cascades has made it challenging to study the influence of adenosine, adenosine analogs and their receptors in health and disease. This review focuses on the role and significance of different adenosine receptors in mediating the effect of adenosine on glucose and lipid homeostasis. J. Cell. Physiol. © 2013 Wiley Periodicals, Inc.
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Affiliation(s)
- Milka Koupenova
- Department of Medicine, Boston University School of Medicine, Boston, MA; Department of Biochemistry, Boston University School of Medicine, Boston, MA; Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA
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Li G, Cong L, Chen X, Chen K, Li F, Zhao AZ. Regulation of adiponectin secretion and expression by insulin and β‐agonists in rat. EUR J LIPID SCI TECH 2012. [DOI: 10.1002/ejlt.201200275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Gang Li
- Departments of Cardiac Surgery, The Second Affiliated Hospital, Harbin Medical University, Harbin, P. R. China
| | - Li Cong
- Departments of Cardiac Surgery, The Second Affiliated Hospital, Harbin Medical University, Harbin, P. R. China
- Departments of Endocrinology and Metabolism, The Second Affiliated Hospital, Harbin Medical University, Harbin, P. R. China
| | - Xiaoqing Chen
- Departments of Endocrinology and Metabolism, The Second Affiliated Hospital, Harbin Medical University, Harbin, P. R. China
| | - Ke Chen
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Fanghong Li
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Allan Z. Zhao
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA, USA
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Pagano C, Dorigo A, Nisoli E, Tonello C, Calcagno A, Tami V, Granzotto M, Carruba MO, Federspil G, Vettor R. Role of Insulin and Free Fatty Acids in the Regulation ofobGene Expression and Plasma Leptin in Normal Rats. ACTA ACUST UNITED AC 2012; 12:2062-9. [PMID: 15687408 DOI: 10.1038/oby.2004.257] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE It is under debate whether free fatty acids (FFAs) play an independent role in the regulation of adipose cell functions. In this study, we evaluated whether leptin secretion induced by FFA is due directly to an increased FFA availability or whether it is mediated by insulin levels. RESEARCH METHODS AND PROCEDURES To test this hypothesis, we compared the effects of six different experimental designs, with different FFA and insulin levels, on plasma leptin: euglycemic clamp, euglycemic clamp + FFA infusion, FFA infusion alone, FFA + somatostatin infusion, somatostatin infusion alone, and saline infusion. RESULTS Our results showed that euglycemic clamp, FFA infusion, or both in combination induced a similar increment of circulating leptin (3.31 +/- 0.30, 3.40 +/- 0.90, and 3.35 +/- 0.80 ng/mL, respectively). Moreover, the inhibition of FFA-induced insulin increase by means of somatostatin infusion completely abolished the rise of leptin in response to FFA (1.05 +/- 0.30 vs. 3.40 +/- 0.90 ng/mL, p < 0.001). DISCUSSION In conclusion, our data showed that the effects of high FFA levels on plasma leptin were mediated by the rise of insulin concentration. These data confirm a major role for insulin in the regulation of leptin secretion from rat adipose tissue and support the hypothesis that leptin secretion is coupled to net triglyceride synthesis in adipose tissue.
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Affiliation(s)
- Claudio Pagano
- Endocrine Metabolic Library, Department of Medical and Surgical Sciences, University of Padova, Padova, Italy.
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Tam J, Cinar R, Liu J, Godlewski G, Wesley D, Jourdan T, Szanda G, Mukhopadhyay B, Chedester L, Liow JS, Innis RB, Cheng K, Rice KC, Deschamps JR, Chorvat RJ, McElroy JF, Kunos G. Peripheral cannabinoid-1 receptor inverse agonism reduces obesity by reversing leptin resistance. Cell Metab 2012; 16:167-79. [PMID: 22841573 PMCID: PMC3832894 DOI: 10.1016/j.cmet.2012.07.002] [Citation(s) in RCA: 270] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/16/2012] [Accepted: 07/06/2012] [Indexed: 12/13/2022]
Abstract
Obesity-related leptin resistance manifests in loss of leptin's ability to reduce appetite and increase energy expenditure. Obesity is also associated with increased activity of the endocannabinoid system, and CB(1) receptor (CB(1)R) inverse agonists reduce body weight and the associated metabolic complications, although adverse neuropsychiatric effects halted their therapeutic development. Here we show that in mice with diet-induced obesity (DIO), the peripherally restricted CB(1)R inverse agonist JD5037 is equieffective with its brain-penetrant parent compound in reducing appetite, body weight, hepatic steatosis, and insulin resistance, even though it does not occupy central CB(1)R or induce related behaviors. Appetite and weight reduction by JD5037 are mediated by resensitizing DIO mice to endogenous leptin through reversing the hyperleptinemia by decreasing leptin expression and secretion by adipocytes and increasing leptin clearance via the kidney. Thus, inverse agonism at peripheral CB(1)R not only improves cardiometabolic risk in obesity but has antiobesity effects by reversing leptin resistance.
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Affiliation(s)
- Joseph Tam
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
- Correspondence: (J.T.), (G.K.)
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jie Liu
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grzegorz Godlewski
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel Wesley
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tony Jourdan
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Gergö Szanda
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bani Mukhopadhyay
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lee Chedester
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert B. Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kejun Cheng
- Chemical Biology Research Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kenner C. Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | | | | | | | - George Kunos
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
- Correspondence: (J.T.), (G.K.)
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Aghamohammadzadeh R, Withers S, Lynch F, Greenstein A, Malik R, Heagerty A. Perivascular adipose tissue from human systemic and coronary vessels: the emergence of a new pharmacotherapeutic target. Br J Pharmacol 2012; 165:670-82. [PMID: 21564083 DOI: 10.1111/j.1476-5381.2011.01479.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED Fat cells or adipocytes are distributed ubiquitously throughout the body and are often regarded purely as energy stores. However, recently it has become clear that these adipocytes are engine rooms producing large numbers of metabolically active substances with both endocrine and paracrine actions. White adipocytes surround almost every blood vessel in the human body and are collectively termed perivascular adipose tissue (PVAT). It is now well recognized that PVAT not only provides mechanical support for any blood vessels it invests, but also secretes vasoactive and metabolically essential cytokines known as adipokines, which regulate vascular function. The emergence of obesity as a major challenge to our healthcare systems has contributed to the growing interest in adipocyte dysfunction with a view to discovering new pharmacotherapeutic agents to help rescue compromised PVAT function. Very few PVAT studies have been carried out on human tissue. This review will discuss these and the hypotheses generated from such research, as well as highlight the most significant and clinically relevant animal studies showing the most pharmacological promise. LINKED ARTICLES This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.
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Zeddou M, Relic B, Malaise O, Charlier E, Desoroux A, Beguin Y, de Seny D, Malaise MG. Differential signalling through ALK-1 and ALK-5 regulates leptin expression in mesenchymal stem cells. Stem Cells Dev 2011; 21:1948-55. [PMID: 22087763 DOI: 10.1089/scd.2011.0321] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Leptin plays a central role in maintaining energy balance, with multiple other systemic effects. Despite leptin importance in peripheral regulation of mesenchymal stem cells (MSC) differentiation, little is known about its expression mechanism. Leptin is often described as adipokine, while it is expressed by other cell types. We have recently shown an in vitro leptin expression, enhanced by glucocorticoids in synovial fibroblasts (SVF). Here, we investigated leptin expression in MSC from bone marrow (BM-MSC) and umbilical cord matrix (UMSC). Results showed that BM-MSC, but not UMSC, expressed leptin that was strongly enhanced by glucocorticoids. Transforming growth factor β1 (TGF-β1) markedly inhibited the endogenous- and glucocorticoid-induced leptin expression in BM-MSC. Since TGF-β1 was shown to signal via ALK-5-Smad2/3 and/or ALK-1-Smad1/5 pathways, we analyzed the expression of proteins from both pathways. In BM-MSC, TGF-β1 increased phosphorylated Smad2 (p-Smad2) expression, while ALK-5 inhibitor (SB431542) induced leptin expression and significantly restored TGF-β1-induced leptin inhibition. In addition, both prednisolone and SB431542 increased p-Smad1/5 expression. These results suggested the ALK-5-Smad2 pathway as an inhibitor of leptin expression, while ALK-1-Smad1/5 as an activator. Indeed, Smad1 expression silencing induced leptin expression inhibition. Furthermore, prednisolone enhanced the expression of TGF-βRII while decreasing p-Smad2 in BM-MSC and SVF but not in UMSC. In vitro differentiation revealed differential osteogenic potential in SVF, BM-MSC, and UMSC that was correlated to their leptin expression potential. Our results suggest that ALK-1/ALK-5 balance regulates leptin expression in MSC. It also underlines UMSC as leptin nonproducer MSC for cell therapy protocols where leptin expression is not suitable.
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Affiliation(s)
- Mustapha Zeddou
- Laboratory of Rheumatology, GIGA-I3, GIGA Research Centre, University and CHU of Liège, Liège, Belgium
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Szczesna M, Zieba D, Klocek-Gorka B, Keisler D. Interactive in vitro effect of prolactin, growth hormone and season on leptin secretion by ovine adipose tissue. Small Rumin Res 2011. [DOI: 10.1016/j.smallrumres.2011.06.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Szkudelski T, Nogowski L, Szkudelska K. Short-term regulation of adiponectin secretion in rat adipocytes. Physiol Res 2011; 60:521-30. [PMID: 21401303 DOI: 10.33549/physiolres.931971] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Adiponectin belongs to the group of biologically active substances secreted by adipocytes and referred to as adipokines. Disturbances in its secretion and/or action are thought to be involved in the pathogenesis of some metabolic diseases. However, regulation of adiponectin secretion is poorly elucidated. In the present study, short-term regulation of adiponectin secretion in primary rat adipocytes was investigated. Isolated rat adipocytes were incubated in Krebs-Ringer buffer containing 5 mM glucose and insulin alone or in the combination with epinephrine, dibutyryl-cAMP, adenosine A(1) receptor antagonist (DPCPX), palmitate, 2-bromopalmitate or inhibitor of mitochondrial electron transport (rotenone). Adipocyte exposure for 2 h to insulin (1-100 nM) significantly increased secretion of adiponectin compared with secretion observed without insulin. Furthermore, secretion of adiponectin from adipocytes incubated with glucose and insulin was reduced by 1 and 2 microM epinephrine, but not by 0.25 and 0.5 microM epinephrine. Under similar conditions, 1 and 2 mM dibutyryl-cAMP substantially diminished secretion of adiponectin, whereas 0.5 mM dibutyryl-cAMP was ineffective. Secretion of adiponectin was found to be effectively decreased by DPCPX. Moreover, adipocyte exposure to rotenone also resulted in a substantial diminution of secretory response of adipocytes incubated for 2 h with glucose and insulin. It was also demonstrated that palmitate and 2-bromopalmitate (0.06-0.5 mM) failed to affect secretion of leptin. The obtained results indicated that in short-term regulation of adiponectin secretion, insulin and epinephrine exert the opposite effects. These effects appeared as early as after 2 h of exposure. Moreover, deprivation of energy or blockade of adenosine action substantially decreased secretion of adiponectin.
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Affiliation(s)
- T Szkudelski
- Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
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García AP, Palou M, Sánchez J, Priego T, Palou A, Picó C. Moderate caloric restriction during gestation in rats alters adipose tissue sympathetic innervation and later adiposity in offspring. PLoS One 2011; 6:e17313. [PMID: 21364997 PMCID: PMC3041800 DOI: 10.1371/journal.pone.0017313] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 01/28/2011] [Indexed: 11/19/2022] Open
Abstract
Maternal prenatal undernutrition predisposes offspring to higher adiposity in adulthood. Mechanisms involved in these programming effects, apart from those described in central nervous system development, have not been established. Here we aimed to evaluate whether moderate caloric restriction during early pregnancy in rats affects white adipose tissue (WAT) sympathetic innervation in the offspring, and its relationship with adiposity development. For this purpose, inguinal and retroperitoneal WAT (iWAT and rpWAT, respectively) were analyzed in male and female offspring of control and 20% caloric-restricted (from 1-12 d of pregnancy) (CR) dams. Body weight (BW), the weight, DNA-content, morphological features and the immunoreactive tyrosine hydroxylase and Neuropeptide Y area (TH+ and NPY+ respectively, performed by immunohistochemistry) of both fat depots, were studied at 25 d and 6 m of age, the latter after 2 m exposure to high fat diet. At 6 m of life, CR males but not females, exhibited greater BW, and greater weight and total DNA-content in iWAT, without changes in adipocytes size, suggesting the development of hyperplasia in this depot. However, in rpWAT, CR males but not females, showed larger adipocyte diameter, with no changes in DNA-content, suggesting the development of hypertrophy. These parameters were not different between control and CR animals at the age of 25 d. In iWAT, both at 25 d and 6 m, CR males but not females, showed lower TH(+) and NPY(+), suggesting lower sympathetic innervation in CR males compared to control males. In rpWAT, at 6 m but not at 25 d, CR males but not females, showed lower TH(+) and NPY(+). Thus, the effects of caloric restriction during gestation on later adiposity and on the differences in the adult phenotype between internal and subcutaneous fat depots in the male offspring may be associated in part with specific alterations in sympathetic innervation, which may impact on WAT architecture.
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Affiliation(s)
- Ana Paula García
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
| | - Mariona Palou
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
| | - Juana Sánchez
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
| | - Teresa Priego
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
| | - Andreu Palou
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
- * E-mail:
| | - Catalina Picó
- Laboratory of Molecular Biology, Nutrition and Biotechnology (Nutrigenomics), University of Balearic Islands and CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Palma de Mallorca, Spain
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Than A, Ye F, Xue R, Ong JW, Poh CL, Chen P. The crosstalks between adipokines and catecholamines. Mol Cell Endocrinol 2011; 332:261-70. [PMID: 21070834 DOI: 10.1016/j.mce.2010.11.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/29/2010] [Accepted: 11/01/2010] [Indexed: 01/11/2023]
Abstract
Adipocytes, which secrete a spectrum of adipokines, play an integral role in metabolism via communications with other endocrine cells. In the present work, we have studied the interplays between adipokines and catecholamines, using 3T3-L1 adipocytes and PC12 cells as the cell models and an integrative experimental platform. We demonstrate that all catecholamines inhibit vesicle trafficking and secretion of leptin and resistin through β-adrenergic receptors, while leptin and resistin enhance the vesicle trafficking and secretion of catecholamines through PKC, PKA, MAPK kinase and Ca(2+) dependent pathways. The crosstalks between adipokines and catecholamines were further corroborated by co-culturing 3T3-L1 adipocytes and PC12 cells. Our findings highlight the importance of adipo-adrenal axis in energy metabolism and the intricate interactions between metabolic hormones.
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Affiliation(s)
- Aung Than
- Division of Bioengineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore
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Deletion of Nhlh2 results in a defective torpor response and reduced Beta adrenergic receptor expression in adipose tissue. PLoS One 2010; 5:e12324. [PMID: 20808804 PMCID: PMC2925948 DOI: 10.1371/journal.pone.0012324] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Accepted: 07/29/2010] [Indexed: 11/19/2022] Open
Abstract
Background Mice with a targeted deletion of the basic helix-loop-helix transcription factor, Nescient Helix-Loop-Helix 2 (Nhlh2), display adult-onset obesity with significant increases in their fat depots, abnormal responses to cold exposure, and reduced spontaneous physical activity levels. These phenotypes, accompanied by the hypothalamic expression of Nhlh2, make the Nhlh2 knockout (N2KO) mouse a useful model to study the role of central nervous system (CNS) control on peripheral tissue such as adipose tissue. Methodology Differences in body temperature and serum analysis of leptin were performed in fasted and ad lib fed wild-type (WT) and N2KO mice. Histological analysis of white (WAT) and brown adipose tissue (BAT) was performed. Gene and protein level expression of inflammatory and metabolic markers were compared between the two genotypes. Principal Findings We report significant differences in serum leptin levels and body temperature in N2KO mice compared with WT mice exposed to a 24-hour fast, suggestive of a defect in both white (WAT) and brown adipose tissue (BAT) function. As compared to WT mice, N2KO mice showed increased serum IL-6 protein and WAT IL-6 mRNA levels. This was accompanied by slight elevations of mRNA for several macrophage markers, including expression of macrophage specific protein F4/80 in adipose, suggestive of macrophage infiltration of WAT in the mutant animals. The mRNAs for β3-adrenergic receptors (β3-AR), β2-AR and uncoupling proteins were significantly reduced in WAT and BAT from N2KO mice compared with WT mice. Conclusions These studies implicate Nhlh2 in the central control of WAT and BAT function, with lack of Nhlh2 leading to adipose inflammation and altered gene expression, impaired leptin response to fasting, all suggestive of a deficient torpor response in mutant animals.
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Hasek BE, Stewart LK, Henagan TM, Boudreau A, Lenard NR, Black C, Shin J, Huypens P, Malloy VL, Plaisance EP, Krajcik RA, Orentreich N, Gettys TW. Dietary methionine restriction enhances metabolic flexibility and increases uncoupled respiration in both fed and fasted states. Am J Physiol Regul Integr Comp Physiol 2010; 299:R728-39. [PMID: 20538896 DOI: 10.1152/ajpregu.00837.2009] [Citation(s) in RCA: 163] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Dietary methionine restriction (MR) is a mimetic of chronic dietary restriction (DR) in the sense that MR increases rodent longevity, but without food restriction. We report here that MR also persistently increases total energy expenditure (EE) and limits fat deposition despite increasing weight-specific food consumption. In Fischer 344 (F344) rats consuming control or MR diets for 3, 9, and 20 mo, mean EE was 1.5-fold higher in MR vs. control rats, primarily due to higher EE during the night at all ages. The day-to-night transition produced a twofold higher heat increment of feeding (3.0 degrees C vs. 1.5 degrees C) in MR vs. controls and an exaggerated increase in respiratory quotient (RQ) to values greater than 1, indicative of the interconversion of glucose to lipid by de novo lipogenesis. The simultaneous inhibition of glucose utilization and shift to fat oxidation during the day was also more complete in MR (RQ approximately 0.75) vs. controls (RQ approximately 0.85). Dietary MR produced a rapid and persistent increase in uncoupling protein 1 expression in brown (BAT) and white adipose tissue (WAT) in conjunction with decreased leptin and increased adiponectin levels in serum, suggesting that remodeling of the metabolic and endocrine function of adipose tissue may have an important role in the overall increase in EE. We conclude that the hyperphagic response to dietary MR is matched to a coordinated increase in uncoupled respiration, suggesting the engagement of a nutrient-sensing mechanism, which compensates for limited methionine through integrated effects on energy homeostasis.
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Affiliation(s)
- Barbara E Hasek
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
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Szkudelska K, Nogowski L, Szkudelski T. The inhibitory effect of resveratrol on leptin secretion from rat adipocytes. Eur J Clin Invest 2009; 39:899-905. [PMID: 19558509 DOI: 10.1111/j.1365-2362.2009.02188.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Resveratrol was found to alleviate consequences of some metabolic disturbances which may be due to inappropriate dietary habits. It decreases mortality, increases insulin sensitivity and improves motor functions; these effects are accompanied by reduced plasma leptin and insulin. Leptin plays a significant role in the regulation of food intake and energy expenditure - elevated level in blood is one of the reasons of leptin-resistance and obesity. In this study, the direct effect of resveratrol on leptin secretion from isolated adipocytes was investigated. MATERIAL AND METHODS Isolated rat adipocytes were incubated with resveratrol (62.5, 125 or 250 microM) and its effects on leptin secretion were studied. Cells were incubated with resveratrol in the presence of glucose (5 and 20 mM) and insulin (10 nM); glucose and nicotinic acid (1 mM); glucose and insulin in the presence of an inhibitor of protein kinase A (H-89, 50 microM) or alanine (10 mM) and insulin. The glucose uptake, glycerol release to the incubation medium, lactate and ATP produced by the cells were also measured. RESULTS Resveratrol inhibited leptin secretion in all experimental designs in a dose-dependent manner. The effect was not accompanied by changes in glycerol release and glucose uptake. Adipocyte exposure to resveratrol enhanced the lactate formation. It was found that resveratrol dramatically reduced ATP in adipocytes. CONCLUSION The obtained results revealed the direct ability of resveratrol to reduce leptin secretion from isolated rat adipocytes. Resveratrol is therefore a compound affecting the endocrine function of adipocytes.
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Affiliation(s)
- K Szkudelska
- Poznan University of Life Sciences, 60-637 Poznan, Poland.
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Shi H, Akunuru S, Bierman JC, Hodge KM, Mitchell MC, Foster MT, Seeley RJ, Reizes O. Diet-induced obese mice are leptin insufficient after weight reduction. Obesity (Silver Spring) 2009; 17:1702-9. [PMID: 19373220 PMCID: PMC4864426 DOI: 10.1038/oby.2009.106] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Behavioral therapies aimed at reducing excess body fat result in limited fat loss after dieting. To understand the causes for maintenance of adiposity, high-fat (HF) diet-induced obese (DIO) mice were switched to a low-fat chow diet, and the effects of chow on histological and molecular alterations of adipose tissue and metabolic parameters were examined. DIO mice reduced and stabilized their body weights after being switched to chow (HF-chow), but retained a greater amount of adiposity than chow-fed mice. Reduction in adipocyte volume, not number, caused a decrease in fat mass. HF-chow mice showed normalized circulating insulin and leptin levels, improved glucose tolerance, and reduced inflammatory status in white adipose tissue (WAT). Circulating leptin levels corrected for fat mass were lower in HF-chow mice. Leptin administration was used to test whether reduced leptin level of HF-chow mice inhibited further fat loss. Leptin treatment led to an additional reduction in adiposity. Finally, HF-HF mice had lower mRNA levels of beta(3) adrenergic receptor (beta(3)-AR) in epididymal WAT (EWAT) compared to chow-fed mice, and diet change led to an increase in the WAT beta(3)-AR mRNA levels that were similar to the levels of chow-fed mice, suggesting an elevation in sympathetic activation of WAT during diet switch relative to HF-HF mice leading to the reduced leptin level and proinflammatory cytokine content. In summary, HF-chow mice were resistant to further fat loss due to leptin insufficiency. Diet alteration from HF to low fat improved metabolic state of DIO mice, although their adiposity was defended at a higher level.
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MESH Headings
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, Brown/pathology
- Adipose Tissue, Brown/physiopathology
- Adipose Tissue, White/metabolism
- Adipose Tissue, White/pathology
- Adipose Tissue, White/physiopathology
- Adiposity
- Animals
- Blood Glucose/metabolism
- Cell Size
- Diet, Fat-Restricted
- Dietary Fats/administration & dosage
- Disease Models, Animal
- Eating
- Fatty Liver/etiology
- Fatty Liver/metabolism
- Fatty Liver/physiopathology
- Feeding Behavior
- Inflammation/etiology
- Inflammation/metabolism
- Inflammation/physiopathology
- Insulin/blood
- Leptin/blood
- Leptin/deficiency
- Macrophages/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Obesity/diet therapy
- Obesity/etiology
- Obesity/metabolism
- Obesity/physiopathology
- RNA, Messenger/metabolism
- Receptors, Adrenergic, beta-3/genetics
- Time Factors
- Weight Loss
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Affiliation(s)
- Haifei Shi
- Obesity Research Center, Department of Psychiatry, University of Cincinnati, Cincinnati, OH
| | - Shailaja Akunuru
- Metabolism Biology, Procter & Gamble Pharmaceuticals, Inc., Health Care Research Center, Mason, OH
| | - John C. Bierman
- Metabolism Biology, Procter & Gamble Pharmaceuticals, Inc., Health Care Research Center, Mason, OH
| | - Karen M. Hodge
- Metabolism Biology, Procter & Gamble Pharmaceuticals, Inc., Health Care Research Center, Mason, OH
| | - M. Chrissy Mitchell
- Metabolism Biology, Procter & Gamble Pharmaceuticals, Inc., Health Care Research Center, Mason, OH
| | - Michelle T. Foster
- Obesity Research Center, Department of Psychiatry, University of Cincinnati, Cincinnati, OH
| | - Randy J. Seeley
- Obesity Research Center, Department of Psychiatry, University of Cincinnati, Cincinnati, OH
- To whom correspondence should be addressed: Randy Seeley, 2170 E.Galbraith Road, Department of Psychiatry, University of Cincinnati, Cincinnati, Ohio 45237, Phone: 513-558-6664, Fax: 513-297-0966, ; Ofer Reizes, Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, NC10, Cleveland, OH 44195, Phone: 216-445-0880, Fax: 216-444-9404,
| | - Ofer Reizes
- Metabolism Biology, Procter & Gamble Pharmaceuticals, Inc., Health Care Research Center, Mason, OH
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH
- To whom correspondence should be addressed: Randy Seeley, 2170 E.Galbraith Road, Department of Psychiatry, University of Cincinnati, Cincinnati, Ohio 45237, Phone: 513-558-6664, Fax: 513-297-0966, ; Ofer Reizes, Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, NC10, Cleveland, OH 44195, Phone: 216-445-0880, Fax: 216-444-9404,
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Lee MJ, Fried SK. Integration of hormonal and nutrient signals that regulate leptin synthesis and secretion. Am J Physiol Endocrinol Metab 2009; 296:E1230-8. [PMID: 19318513 PMCID: PMC2692400 DOI: 10.1152/ajpendo.90927.2008] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This review summarizes recent advances in our understanding of the pre- and posttranscriptional mechanisms that regulate leptin production and secretion in adipocytes. Basal leptin production is proportional to the status of energy stores, i.e., fat cell size, and this is mainly regulated by alterations in leptin mRNA levels. Leptin mRNA levels are regulated by hormones, including glucocorticoids and catecholamines, but little is known about the transcriptional mechanisms involved. Leptin synthesis and secretion is also acutely modulated in response to hormones such as insulin and the availability of metabolic fuels. Acute variations in leptin production over a time course of minutes to hours are mediated at the levels of both translation and secretion. Increases in amino acids and insulin after a meal activate the mammalian target of rapamycin (mTOR) pathway, leading to an increase in specific rates of leptin biosynthesis. Cross-talk among mTOR, PKA, and AMP-activated protein kinase pathways appears to integrate hormonal and nutrient signals that regulate leptin mRNA translation, at least in part through mechanisms involving its 5'- and 3'-untranslated regions. In addition, the rate of leptin secretion from preformed stores in response to hormonal cues is also regulated. Insulin stimulates, and adrenergic agonists inhibit, leptin secretion, and this likely contributes to variations in the magnitude of nutrition-related leptin excursions and oscillations. Overall, the study of leptin production has contributed to a deepening understanding of leptin biology and, more broadly, to our understanding of the cellular and molecular mechanisms by which the adipocyte integrates hormonal and nutrient signals to regulate adipokine production.
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Affiliation(s)
- Mi-Jeong Lee
- Division of Endocrinology, Diabetes, and Nutrition, Department of Medicine, University of Maryland, School of Medicine, Baltimore, MD, USA
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Morrison CD, Huypens P, Stewart LK, Gettys TW. Implications of crosstalk between leptin and insulin signaling during the development of diet-induced obesity. BIOCHIMICA ET BIOPHYSICA ACTA 2009; 1792:409-16. [PMID: 18852044 PMCID: PMC2713765 DOI: 10.1016/j.bbadis.2008.09.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 09/09/2008] [Accepted: 09/14/2008] [Indexed: 01/02/2023]
Abstract
Insulin and leptin play complementary roles in regulating the consumption, uptake, oxidation and storage of nutrients. Chronic consumption of diets that contain a high proportion of calories from saturated fat induces a progressive deterioration in function of both hormones. Certain rat lines and strains of mice are particularly sensitive to the obesogenic and diabetogenic effects of high fat diets, and have been used extensively to study the developmental progression of insulin and leptin resistance in relation to the increasing adiposity that is characteristic of their response to these diets. Some aspects of the diminished efficacy of each hormone are secondary to increased adiposity but a consensus is emerging to support the view that direct effects of dietary components or their metabolites, independent of the resulting obesity, play important roles in development of insulin and leptin resistance. In this minireview, we will examine the implications of crosstalk between leptin and insulin signaling during the development of diet-induced obesity, emphasizing potential interactions between pathways that occur among target sites, and exploring how these interactions may influence the progression of obesity and diabetes.
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Affiliation(s)
- Christopher D Morrison
- Laboratory of Neurosignaling, Pennington Biomedical Research Center, Baton Rouge, LA, USA
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Abstract
Since the effect of smoking on plasma leptin has been divergent in clinical trials, which might have occurred due to selection of heterogeneous study populations, we investigated whether there is such an association in a group of healthy, non-obese, young male adults. A total of 54 smokers (mean age: 21.18+/-1.62; body mass index (BMI): 19.60+/-0.85) and 26 non-smokers (mean age 21.69+/-3.0; BMI: 21.59+/-1.39) with similar daily physical activities and diet and without any documented disease were enrolled, and their plasma leptin levels were determined for the comparison between the two groups. The mean BMI and plasma leptin of smokers were significantly lower than in non-smokers. Plasma leptin in the smokers group correlated inversely with BMI and the amount of daily smoking. Below BMI 20 kg/m(2) and between 20.0 and 20.9 kg/m(2) the plasma leptin levels in smokers were significantly lower when compared to non-smokers. Plasma leptin is decreased in healthy, young non-obese male smokers independently of the amount of body fat. High amount of smoking is associated with lower serum leptin as well.
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Affiliation(s)
- Bayram Koc
- Department of Internal Medicine, Gulhane School of Medicine, Etlik, Ankara, Turkey
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48
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Schmoller A, Voss M, Gehring H, Rudolf S, Schweiger U, Schultes B, Oltmanns KM. Short Hypoxia Does not Affect Plasma Leptin in Healthy Men under Euglycemic Clamp Conditions. Int J Endocrinol 2009; 2009:270698. [PMID: 19946426 PMCID: PMC2778504 DOI: 10.1155/2009/270698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 03/12/2009] [Indexed: 02/04/2023] Open
Abstract
Leptin is involved in the endocrine control of energy expenditure and body weight regulation. Previous studies emphasize a relationship between hypoxic states and leptin concentrations. The aim of this study was to investigate the effects of acute hypoxia on leptin concentrations in healthy subjects. We examined 14 healthy men. Hypoxic conditions were induced by decreasing oxygen saturation to 75% for 30 minutes. Plasma leptin concentrations were determined at baseline, after 3 hours of euglycemic clamping, during hypoxia, and repeatedly the following 2.5 hours thereafter. Our results show an increase of plasma leptin concentrations in the course of 6 hours of hyperinsulinemic-euglycemic clamping which may reflect diurnal rhythmicity. Notwithstanding, there was no difference between levels of leptin in the hypoxic and the normoxic condition (P = .2). Since we did not find any significant changes in leptin responses upon hypoxia, plasma leptin levels do not seem to be affected by short hypoxic episodes of moderate degree.
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Affiliation(s)
- Andre Schmoller
- Department of Psychiatry and Psychotherapy, University of Luebeck, D-23538 Luebeck, Germany
| | - Michaela Voss
- Department of Psychiatry and Psychotherapy, University of Luebeck, D-23538 Luebeck, Germany
| | - Hartmut Gehring
- Department of Anaesthesiology, University of Luebeck, D-23538 Luebeck, Germany
| | - Sebastian Rudolf
- Department of Psychiatry and Psychotherapy, University of Luebeck, D-23538 Luebeck, Germany
| | - Ulrich Schweiger
- Department of Psychiatry and Psychotherapy, University of Luebeck, D-23538 Luebeck, Germany
| | - Bernd Schultes
- Interdisciplinary Obesity Center, St. Gallen, CH-9400 Rorschach, Switzerland
| | - Kerstin M. Oltmanns
- Department of Psychiatry and Psychotherapy, University of Luebeck, D-23538 Luebeck, Germany
- Department of Neuroendocrinology, University of Luebeck, D-23538 Luebeck, Germany
- *Kerstin M. Oltmanns:
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Abstract
Recent studies consistently support a hypoxia response in the adipose tissue in obese animals. The observations have led to the formation of an exciting concept, adipose tissue hypoxia (ATH), in the understanding of major disorders associated with obesity. ATH may provide cellular mechanisms for chronic inflammation, macrophage infiltration, adiponectin reduction, leptin elevation, adipocyte death, endoplasmic reticulum stress and mitochondrial dysfunction in white adipose tissue in obesity. The concept suggests that inhibition of adipogenesis and triglyceride synthesis by hypoxia may be a new mechanism for elevated free fatty acids in the circulation in obesity. ATH may represent a unified cellular mechanism for a variety of metabolic disorders and insulin resistance in patients with metabolic syndrome. It suggests a new mechanism of pathogenesis of insulin resistance and inflammation in obstructive sleep apnea. In addition, it may help us to understand the beneficial effects of caloric restriction, physical exercise and angiotensin II inhibitors in the improvement of insulin sensitivity. In this review article, literatures are reviewed to summarize the evidence and possible cellular mechanisms of ATH. The directions and road blocks in the future studies are analyzed.
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50
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Goossens GH, Jocken JWE, van Baak MA, Jansen EHJM, Saris WHM, Blaak EE. Short-term beta-adrenergic regulation of leptin, adiponectin and interleukin-6 secretion in vivo in lean and obese subjects. Diabetes Obes Metab 2008; 10:1029-38. [PMID: 18435774 DOI: 10.1111/j.1463-1326.2008.00856.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM Adipose tissue and skeletal muscle are endocrine organs, secreting substances that have been implicated in obesity-related disorders. This study examined short-term beta-adrenergic regulation of circulating leptin, adiponectin and interleukin-6 (IL-6) concentrations and secretion from abdominal subcutaneous adipose tissue and muscle (IL-6) in vivo in lean and obese subjects. METHODS Systemic concentrations and net fluxes of leptin, adiponectin and IL-6 across abdominal subcutaneous adipose tissue and forearm skeletal muscle (IL-6) were assessed before and during beta-adrenergic stimulation (intravenous isoprenaline infusion) in 13 lean and 10 obese men. RESULTS Basal circulating leptin concentrations were higher in the obese (p < 0.001), while circulating adiponectin (p = 0.45) and IL-6 concentrations (p = 0.41) were not different between groups. beta-Adrenergic stimulation decreased leptin concentrations in both groups (p < 0.01), but did not reduce net abdominal subcutaneous adipose tissue leptin release. Increased leptin clearance and/or decreased leptin secretion from other fat depots may explain the reduction in leptin concentrations. Adiponectin concentrations remained unchanged during beta-adrenergic stimulation in both groups. beta-Adrenergic stimulation increased IL-6 concentration, which was more pronounced in the obese (p = 0.01 vs. lean). This cannot be explained by increased IL-6 release per unit abdominal subcutaneous adipose tissue and muscle but might be because of the increased fat mass and fat-free mass at whole-body level. CONCLUSIONS Short-term beta-adrenergic stimulation decreases leptin concentrations, which cannot be explained by reduced net leptin release from abdominal subcutaneous adipose tissue, while it elevates IL-6 concentration partly by increased release from this fat depot and muscle. Finally, beta-adrenergic stimulation has no short-term regulatory role in adiponectin secretion.
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Affiliation(s)
- G H Goossens
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands.
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