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de Sousa ME, Gusmao DO, Dos Santos WO, Moriya HT, de Lima FF, List EO, Kopchick JJ, Donato J. Fasting and prolonged food restriction differentially affect GH secretion independently of GH receptor signaling in AgRP neurons. J Neuroendocrinol 2024; 36:e13254. [PMID: 36964750 DOI: 10.1111/jne.13254] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/14/2023]
Abstract
Growth hormone (GH) receptor (GHR) is abundantly expressed in neurons that co-release the agouti-related protein (AgRP) and neuropeptide Y (NPY) in the arcuate nucleus of the hypothalamus (ARH). Since ARHAgRP/NPY neurons regulate several hypothalamic-pituitary-endocrine axes, this neuronal population possibly modulates GH secretion via a negative feedback loop, particularly during food restriction, when ARHAgRP/NPY neurons are highly active. The present study aims to determine the importance of GHR signaling in ARHAgRP/NPY neurons on the pattern of GH secretion in fed and food-deprived male mice. Additionally, we compared the effect of two distinct situations of food deprivation: 16 h of fasting or four days of food restriction (40% of usual food intake). Overnight fasting strongly suppressed both basal and pulsatile GH secretion. Animals lacking GHR in ARHAgRP/NPY neurons (AgRP∆GHR mice) did not exhibit differences in GH secretion either in the fed or fasted state, compared to control mice. In contrast, four days of food restriction increased GH pulse frequency, basal GH secretion, and pulse irregularity/complexity (measured by sample entropy), whereas pulsatile GH secretion was not affected in both control and AgRP∆GHR mice. Hypothalamic Ghrh mRNA levels were unaffected by fasting or food restriction, but Sst expression increased in acutely fasted mice, but decreased after prolonged food restriction in both control and AgRP∆GHR mice. Our findings indicate that short-term fasting and prolonged food restriction differentially affect the pattern of GH secretion, independently of GHR signaling in ARHAgRP/NPY neurons.
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Affiliation(s)
- Maria E de Sousa
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Daniela O Gusmao
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Willian O Dos Santos
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
| | - Henrique T Moriya
- Biomedical Engineering Laboratory, Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, 05508-010, Brazil
| | - Felipe F de Lima
- Biomedical Engineering Laboratory, Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, 05508-010, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, 45701, USA
| | - Jose Donato
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, 05508-000, Brazil
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Haspula D, Cui Z. Neurochemical Basis of Inter-Organ Crosstalk in Health and Obesity: Focus on the Hypothalamus and the Brainstem. Cells 2023; 12:1801. [PMID: 37443835 PMCID: PMC10341274 DOI: 10.3390/cells12131801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/23/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Precise neural regulation is required for maintenance of energy homeostasis. Essential to this are the hypothalamic and brainstem nuclei which are located adjacent and supra-adjacent to the circumventricular organs. They comprise multiple distinct neuronal populations which receive inputs not only from other brain regions, but also from circulating signals such as hormones, nutrients, metabolites and postprandial signals. Hence, they are ideally placed to exert a multi-tier control over metabolism. The neuronal sub-populations present in these key metabolically relevant nuclei regulate various facets of energy balance which includes appetite/satiety control, substrate utilization by peripheral organs and glucose homeostasis. In situations of heightened energy demand or excess, they maintain energy homeostasis by restoring the balance between energy intake and expenditure. While research on the metabolic role of the central nervous system has progressed rapidly, the neural circuitry and molecular mechanisms involved in regulating distinct metabolic functions have only gained traction in the last few decades. The focus of this review is to provide an updated summary of the mechanisms by which the various neuronal subpopulations, mainly located in the hypothalamus and the brainstem, regulate key metabolic functions.
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Affiliation(s)
- Dhanush Haspula
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA
| | - Zhenzhong Cui
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA;
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Costa-e-Sousa RH, Rorato R, Hollenberg AN, Vella KR. Regulation of Thyroid Hormone Levels by Hypothalamic Thyrotropin-Releasing Hormone Neurons. Thyroid 2023; 33:867-876. [PMID: 37166378 PMCID: PMC10354708 DOI: 10.1089/thy.2023.0173] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Background: Thyrotropin-releasing hormone (TRH) neurons in the paraventricular nucleus of the hypothalamus (PVN) have been identified as direct regulators of thyrotropin (TSH) and thyroid hormone (TH) levels. They play a significant role in context of negative feedback by TH at the level of TRH gene expression and during fasting when TH levels fall due, in part, to suppression of TRH gene expression. Methods: To test these functions directly for the first time, we used a chemogenetic approach and activated PVN TRH neurons in both fed and fasted mice. Next, to demonstrate the signals that regulate the fasting response in TRH neurons, we activated or inhibited agouti-related protein (AgRP)/neuropeptide Y (NPY) neurons in the arcuate nucleus of the hypothalamus of fed or fasted mice, respectively. To determine if the same TRH neurons responsive to melanocortin signaling mediate negative feedback by TH, we disrupted the thyroid hormone receptor beta (TRβ) in all melanocortin 4 receptor (MC4R) neurons in the PVN. Results: Activation of TRH neurons led to increased TSH and TH levels within 2 hours demonstrating the specific role of PVN TRH neurons in the regulation of the hypothalamic-pituitary-thyroid (HPT) axis. Moreover, activation of PVN TRH neurons prevented the fall in TH levels in fasting mice. Stimulation of AgRP/NPY neurons led to a fall in TH levels despite increasing feeding. Inhibition of these same neurons prevented the fall in TH levels during a fast presumably via their ability to directly regulate PVN TRH neurons via, in part, the MC4R. Surprisingly, TH-mediated feedback was not impaired in mice lacking TRβ in MC4R neurons. Conclusions: TRH neurons are major regulators of the HPT axis and the fasting-induced suppression of TH levels. The latter relies, at least in part, on the activation of AgRP/NPY neurons in the arcuate nucleus. Interestingly, present data do not support an important role for TRβ signaling in regulating MC4R neurons in the PVN. Thus, it remains possible that different subsets of TRH neurons in the PVN mediate responses to energy balance and to TH feedback.
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Affiliation(s)
- Ricardo H. Costa-e-Sousa
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Chobanian and Avedisian School of Medicine, Boston University and Boston Medical Center, Boston, Massachusetts, USA
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, Weill Cornell Medicine, New York, New York, USA
| | - Rodrigo Rorato
- Department of Biophysics, Paulista Medical School, Federal University of São Paulo, São Paulo, Brazil
| | - Anthony N. Hollenberg
- Department of Medicine, Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Chobanian and Avedisian School of Medicine, Boston University and Boston Medical Center, Boston, Massachusetts, USA
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, Weill Cornell Medicine, New York, New York, USA
| | - Kristen R. Vella
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, Weill Cornell Medicine, New York, New York, USA
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Ehrhardt RA, Giesy SL, Hileman SM, Houseknecht KL, Boisclair YR. Effects of the central melanocortin system on feed intake, metabolic hormones and insulin action in the sheep. J Anim Sci 2023; 101:skad398. [PMID: 38035762 PMCID: PMC10734672 DOI: 10.1093/jas/skad398] [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: 09/05/2023] [Accepted: 11/29/2023] [Indexed: 12/02/2023] Open
Abstract
Voluntary feed intake is insufficient to meet the nutrient demands associated with late pregnancy in prolific ewes and early lactation in high-yielding dairy cows. Under these conditions, peripheral signals such as growth hormone and ceramides trigger adaptations aimed at preserving metabolic well-being. Recent work in rodents has shown that the central nervous system-melanocortin (CNS-MC) system, consisting of alpha-melanocyte-stimulating hormone (α-MSH) and agouti-related peptide (AGRP) acting respectively as agonist and antagonist on central MC receptors, contributes to the regulation of some of the same adaptations. To assess the effects of the CNC-MC on peripheral adaptations in ruminants, ewes were implanted with an intracerebroventricular cannula in the third ventricle and infused over days with artificial cerebrospinal fluid (aCSF), the α-MSH analog melanotan-I (MTI), or AGRP. Infusion of MTI at 0.03 nmol/h reduced intake, expressed as a fold of maintenance energy requirement (M), from 1.8 to 1.1 M (P < 0.0001), whereas AGRP at 0.3 nmol/h increased intake from 1.8 to 2.0 M (P < 0.01); these doses were used in all subsequent experiments. To assess the effect of MTI on plasma variables, sheep were fed ad libitum and infused with aCSF or MTI or pair-fed to MTI-treated sheep and infused with aCSF (aCSFPF). Feed intake of the MTI and aCSFPF groups was 40% lower than the aCSF group (P < 0.0001). MTI increased plasma triiodothyronine and thyroxine in an intake-independent manner (P < 0.05 or less) but was devoid of effects on plasma glucose, insulin, and cortisol. None of these variables were altered by AGRP infusion in sheep fed at a fixed intake of 1.6 M. To assess the effect of CNS-MC activation on insulin action, ewes were infused with aCSF or MTI over the last 3 d of a 14-d period when energy intake was limited to 0.3 M and studied under basal conditions and during hyperinsulinemic-euglycemic clamps. MTI had no effect on plasma glucose, plasma insulin, or glucose entry rate under basal conditions but blunted the ability of insulin to inhibit endogenous glucose production during hyperinsulinemic-euglycemic clamps (P < 0.0001). Finally, MTI tended to reduce plasma leptin in sheep fed at 0.3 M (P < 0.08), and this effect became significant at 0.6 M (P < 0.05); MTI had no effect on plasma adiponectin irrespective of feeding level. These data suggest a role for the CNC-MC in regulating metabolic efficiency and peripheral insulin action.
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Affiliation(s)
- Richard A Ehrhardt
- Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI 48824, USA
| | - Sarah L Giesy
- Department of Animal Science, Cornell University, Ithaca, NY 14853, USA
| | - Stanley M Hileman
- Department of Physiology, Pharmacology, and Toxicology, West Virginia University, Morgantown, WV 26506, USA
| | - Karen L Houseknecht
- Department of Biomedical Sciences, University of New England, Portland, ME 04103, USA
| | - Yves R Boisclair
- Department of Animal Science, Cornell University, Ithaca, NY 14853, USA
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Hinney A, Körner A, Fischer-Posovszky P. The promise of new anti-obesity therapies arising from knowledge of genetic obesity traits. Nat Rev Endocrinol 2022; 18:623-637. [PMID: 35902734 PMCID: PMC9330928 DOI: 10.1038/s41574-022-00716-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2022] [Indexed: 02/07/2023]
Abstract
Obesity is a multifactorial and complex disease that often manifests in early childhood with a lifelong burden. Polygenic and monogenic obesity are driven by the interaction between genetic predisposition and environmental factors. Polygenic variants are frequent and confer small effect sizes. Rare monogenic obesity syndromes are caused by defined pathogenic variants in single genes with large effect sizes. Most of these genes are involved in the central nervous regulation of body weight; for example, genes of the leptin-melanocortin pathway. Clinically, patients with monogenic obesity present with impaired satiety, hyperphagia and pronounced food-seeking behaviour in early childhood, which leads to severe early-onset obesity. With the advent of novel pharmacological treatment options emerging for monogenic obesity syndromes that target the central melanocortin pathway, genetic testing is recommended for patients with rapid weight gain in infancy and additional clinical suggestive features. Likewise, patients with obesity associated with hypothalamic damage or other forms of syndromic obesity involving energy regulatory circuits could benefit from these novel pharmacological treatment options. Early identification of patients affected by syndromic obesity will lead to appropriate treatment, thereby preventing the development of obesity sequelae, avoiding failure of conservative treatment approaches and alleviating stigmatization of patients and their families.
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Affiliation(s)
- Anke Hinney
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy and University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
- Center for Translational Neuro- and Behavioral Sciences, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Antje Körner
- Leipzig University, Medical Faculty, Hospital for Children and Adolescents, Centre of Paediatric Research (CPL), Leipzig, Germany
- LIFE Child, Leipzig Research Centre for Civilization Diseases, Leipzig, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
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de Souza GO, Wasinski F, Donato J. Characterization of the metabolic differences between male and female C57BL/6 mice. Life Sci 2022; 301:120636. [PMID: 35568227 DOI: 10.1016/j.lfs.2022.120636] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/06/2022] [Accepted: 05/09/2022] [Indexed: 01/22/2023]
Abstract
AIMS The present study aims to compare the responses between male and female C57BL/6 mice to multiple metabolic challenges to understand the importance of sex in the control of energy homeostasis. MAIN METHODS Male and female C57BL/6 mice were subjected to nutritional and hormonal challenges, such as food restriction and refeeding, diet-induced obesity, feeding response to ghrelin and leptin, ghrelin-induced growth hormone secretion, and central responsiveness to ghrelin and leptin. The hypothalamic expression of transcripts that control energy homeostasis was also evaluated. KEY FINDINGS Male mice lost more weight and lean body mass in response to food restriction, compared to females. During refeeding, males accumulated more body fat and exhibited lower energy expenditure and glycemia, as compared to females. Additionally, female mice exhibited a higher protection against diet-induced obesity and related metabolic imbalances in comparison to males. Low dose ghrelin injection elicited higher food intake and growth hormone secretion in male mice, whereas the acute anorexigenic effect of leptin was more robust in females. However, the sex differences in the feeding responses to ghrelin and leptin were not explained by variations in the central responsiveness to these hormones nor by differences in the fiber density from arcuate nucleus neurons. Female, but not male, mice exhibited compensatory increases in hypothalamic Pomc mRNA levels in response to diet-induced obesity. SIGNIFICANCE Our findings revealed several sexually differentiated responses to metabolic challenges in C57BL/6 mice, highlighting the importance of taking into account sex differences in metabolic studies.
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Affiliation(s)
- Gabriel O de Souza
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo 05508-000, Brazil
| | - Frederick Wasinski
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo 05508-000, Brazil
| | - Jose Donato
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo 05508-000, Brazil..
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7
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Mele C, Mai S, Cena T, Pagano L, Scacchi M, Biondi B, Aimaretti G, Marzullo P. The pattern of TSH and fT4 levels across different BMI ranges in a large cohort of euthyroid patients with obesity. Front Endocrinol (Lausanne) 2022; 13:1029376. [PMID: 36313780 PMCID: PMC9606412 DOI: 10.3389/fendo.2022.1029376] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
PURPOSE A multifold association relates the hypothalamo-pituitary-thyroid axis to body weight. The potential underlying mechanisms are incompletely understood. Further, the mild severity of obesity and the small proportion of individuals with obesity in so far published cohort studies provide little insights on metabolic correlates of thyroid function in obesity. METHODS We retrospectively enrolled 5009 adults with obesity (F/M, 3448/1561; age range, 18-87 years; BMI range, 30.0-82.7 kg/m2), without known thyroid disease in a study on TSH and fT4 levels, lipid profile, glucose homeostasis and insulin resistance, anthropometric parameters including BIA-derived fat mass (%FM) and fat-free mass (FFM). RESULTS The overall reference interval for TSH in our obese cohort was 0.58-5.07 mIU/L. As subgroups, females and non-smokers showed higher TSH levels as compared to their counterparts (p<0.0001 for both), while fT4 values were comparable between groups. There was a significant upward trend for TSH levels across incremental BMI classes in females, while the opposite trend was seen for fT4 levels in males (p<0.0001 for both). Expectedly, TSH was associated with %FM and FFM (p<0,0001 for both). TSH and fT4 showed correlations with several metabolic variables, and both declined with aging (TSH, p<0.0001; fT4, p<0.01). In a subgroup undergoing leptin measurement, leptin levels were positively associated with TSH levels (p<0.01). At the multivariable regression analysis, in the group as a whole, smoking habit emerged as the main independent predictor of TSH (β=-0.24, p<0.0001) and fT4 (β=-0.25, p<0.0001) levels. In non-smokers, %FM (β=0.08, p<0.0001) and age (β=-0.05, p<0.001) were the main significant predictors of TSH levels. In the subset of nonsmokers having leptin measured, leptin emerged as the strongest predictor of TSH levels (β=0.17, p<0.01). CONCLUSIONS Our study provides evidence of a gender- and smoking-dependent regulation of TSH levels in obesity.
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Affiliation(s)
- Chiara Mele
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- *Correspondence: Chiara Mele,
| | - Stefania Mai
- Istituto Auxologico Italiano, IRCCS, Laboratory of Metabolic Research, S. Giuseppe Hospital, Piancavallo, Italy
| | - Tiziana Cena
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Loredana Pagano
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Massimo Scacchi
- Istituto Auxologico Italiano, IRCCS, Division of General Medicine, S. Giuseppe Hospital, Piancavallo, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Bernadette Biondi
- Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Gianluca Aimaretti
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Paolo Marzullo
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Istituto Auxologico Italiano, IRCCS, Laboratory of Metabolic Research, S. Giuseppe Hospital, Piancavallo, Italy
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Campos AMP, Wasinski F, Klein MO, Bittencourt JC, Metzger M, Donato J. Fasting reduces the number of TRH immunoreactive neurons in the hypothalamic paraventricular nucleus of male rats, but not in mice. Neurosci Lett 2021; 752:135832. [PMID: 33746008 DOI: 10.1016/j.neulet.2021.135832] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/10/2021] [Accepted: 03/12/2021] [Indexed: 01/09/2023]
Abstract
During fasting or weight loss, the fall in leptin levels leads to suppression of thyrotropin-releasing hormone (TRH) expression in the paraventricular nucleus of the hypothalamus (PVH) and, consequently, inhibition of the hypothalamic-pituitary-thyroid (HPT) axis. However, differently than rats, just few PVHTRH neurons express the leptin receptor in mice. In the present study, male adult rats and mice were submitted to 48 -h fasting to evaluate the consequences on proTRH peptide expression at the PVH level. Additionally, the proTRH peptide expression was also assessed in the brains of leptin-deficient (Lepob/ob) mice. We observed that approximately 50 % of PVHTRH neurons of leptin-injected rats exhibited phosphorylation of the signal transducer and activator of transcription 3 (pSTAT3), a marker of leptin receptor activation. In contrast, very few PVHTRH neurons of leptin-injected mice exhibited pSTAT3. Rats submitted to 48 -h fasting showed a significant reduction in the number of PVHTRH immunoreactive neurons, as compared to fed rats. On the other hand, no changes in the number of PVHTRH immunoreactive neurons were observed between fasted and fed mice. Next, the number of TRH immunoreactive cells was determined in the PVH, dorsomedial nucleus of the hypothalamus and nucleus raphe pallidus of Lepob/ob and wild-type mice and no significant differences were observed, despite reduced plasma T4 levels in Lepob/ob mice. Taken together, these findings provide additional evidence of the important species-specific differences in the mechanisms used by fasting and/or leptin to regulate the HPT axis.
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Affiliation(s)
- Ana M P Campos
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil
| | - Frederick Wasinski
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil
| | - Marianne O Klein
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Anatomia, Sao Paulo, Brazil
| | - Jackson C Bittencourt
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Anatomia, Sao Paulo, Brazil
| | - Martin Metzger
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil
| | - Jose Donato
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil.
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HECHT FABIO, CAZARIN JULIANA, ROSSETTI CAMILAL, ROSENTHAL DORIS, ARAUJO RENATAL, CARVALHO DENISEP. Leptin negatively regulates thyroid function of Wistar rats. AN ACAD BRAS CIENC 2021. [DOI: 10.1590/0001-3765202120201551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- FABIO HECHT
- Universidade Federal do Rio de Janeiro, Brazil
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Obesity treatment effect in Danish children and adolescents carrying Melanocortin-4 Receptor mutations. Int J Obes (Lond) 2020; 45:66-76. [PMID: 32921795 PMCID: PMC7752754 DOI: 10.1038/s41366-020-00673-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 08/10/2020] [Accepted: 09/03/2020] [Indexed: 11/20/2022]
Abstract
Objectives To determine the prevalence of Melanocortin-4 Receptor (MC4R) mutations in a cohort of children and adolescents with overweight or obesity and to determine whether treatment responses differed between carriers and noncarriers. Methods Using target region capture sequencing, an MC4R mutation screen was performed in 1261 Danish children and adolescents enrolled at a tertiary multidisciplinary childhood obesity treatment center. Measurements of anthropometrics, blood pressure, fasting blood biochemistry including lipid and hormone levels, and dual-energy X-ray absorptiometry were performed at baseline and throughout treatment. Results Of 1209 children and adolescents that met all criteria to be included in the described analyses, 30 (2.5%) carried damaging or unresolved MC4R mutations. At baseline, mutation carriers exhibited higher concentrations of plasma thyroid-stimulating hormone (p = 0.003), and lower concentrations of plasma thyroxine (p = 0.010) compared to noncarriers. After a median of 1 year of treatment (range 0.5–4.0 years), body mass index (BMI) standard deviation score (SDS) was reduced in noncarriers but not in carriers, and this difference in treatment response was statistically significant (p = 0.005). Furthermore, HDL cholesterol was reduced in carriers, a response significantly different from that of noncarriers (p = 0.017). Conclusion Among Danish children and adolescents with overweight or obesity entering a tertiary lifestyle intervention, 2.5% carried damaging or unresolved MC4R mutations. In contrast to noncarriers, carriers of damaging or unresolved MC4R mutations failed to reduce their BMI SDS during obesity treatment, indicating a need for personalized treatment based on the MC4R genotype.
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Campos AMP, Teixeira PDS, Wasinski F, Klein MO, Bittencourt JC, Metzger M, Donato J. Differences between rats and mice in the leptin action on the paraventricular nucleus of the hypothalamus: Implications for the regulation of the hypothalamic-pituitary-thyroid axis. J Neuroendocrinol 2020; 32:e12895. [PMID: 32840013 DOI: 10.1111/jne.12895] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 07/03/2020] [Accepted: 07/20/2020] [Indexed: 12/23/2022]
Abstract
Previous studies indicate that leptin regulates the hypothalamic-pituitary-thyroid (HPT) axis via direct and indirect mechanisms. The indirect mechanism involves leptin action in pro-opiomelanocortin (POMC)- and agouti-related peptide (AgRP)-expressing neurones. These cells innervate the paraventricular nucleus of the hypothalamus (PVH) where they modulate hypophysiotrophic thyrotrophin-releasing hormone (TRH)-producing neurones. The direct mechanism involves the expression of leptin receptor (LepR) in a subpopulation of PVH TRH neurones. However, to our knowledge, the existence of LepR in PVH TRH neurones of mice has not been clearly confirmed. Therefore, we investigated possible species-specific differences between rats and mice with respect to the mechanisms recruited by leptin to regulate the HPT axis. We observed that an acute leptin injection induced phosphorylated signal transducer and activator of transcription 3 (pSTAT3), a marker of leptin-responsive cells, in 46.2 ± 8.0% of PVH proTRH immunoreactive neurones in rats. By contrast, an insignificant number of proTRH positive neurones in the mouse PVH co-expressed leptin-induced pSTAT3 or LepR. Similarly, central leptin injection increased the percentage of PVH proTRH neurones containing cAMP response element-binding protein phosphorylation in rats, but not in mice. We investigated the innervation of AgRP and POMC axons in the PVH and observed that rats exhibited a denser POMC innervation in the PVH compared to mice, whereas rats and mice showed similar density of AgRP axons in the PVH. In conclusion, rats and mice exhibit important species-specific differences in the direct and indirect mechanisms used by leptin to regulate the HPT axis.
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Affiliation(s)
- Ana M P Campos
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Pryscila D S Teixeira
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Frederick Wasinski
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Marianne O Klein
- Departamento de Anatomia, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Jackson C Bittencourt
- Departamento de Anatomia, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Martin Metzger
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Jose Donato
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
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de Gortari P, Alcántara-Alonso V, Matamoros-Trejo G, Amaya MI, Alvarez-Salas E. Differential effects of leptin administration on feeding and HPT axis function in early-life overfed adult rats. Peptides 2020; 127:170285. [PMID: 32105809 DOI: 10.1016/j.peptides.2020.170285] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 01/29/2020] [Accepted: 02/22/2020] [Indexed: 12/18/2022]
Abstract
Early-life overfeeding (OF) disrupts neuroendocrine systems, energy homeostasis and food intake regulation inducing overeating and overweight in adults. Adult rats raised in small litters during lactation, display hyperphagia and overweight since weaning and exhibit a decrease in thyrotropin-releasing hormone (TRH) mRNA expression in hypothalamic paraventricular nucleus (PVN). This is counterintuitive because TRH expression should increase to activate the hypothalamic-pituitary-thyroid (HPT) axis and promote energy expenditure, thus, HPT axis seems inhibited in OF rats. Leptin, an adipocyte-synthesized hormone that stimulates hypothalamic TRH expression, enhances both TRH anorectic effects and HPT axis-induced metabolic rate. To evaluate hypothalamic resistance to the anorectic and HPT axis stimulatory actions of leptin, we injected leptin i.p. to ad libitum fed and to 48-h fasted adult control (reared in normal litters) and to small-litter reared (OF) male Wistar rats. Findings showed that HPT axis was still responsive to leptin, since PVN TRH mRNA levels, median eminence TRH release and T4 serum concentration increased in both, ad libitum and fasted OF rats after leptin administrations. Leptin was ineffective to reduce feeding of OF animals. By comparing leptin receptor (ObRb) expression changes between arcuate and PVN nuclei, we observed that arcuate ObRb was not modified in response to leptin administrations in OF rats, likely accounting for the differential effects in feeding and HPT axis function. Nevertheless, ObRb expression was modified by leptin in the PVN of OF rats to the same extent as controls; this supports the hormone's role as a therapeutic agent for early onset obesity in adults.
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Affiliation(s)
- P de Gortari
- Molecular Neurophysiology Laboratory, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, Calz. México-Xochimilco No. 101, San Lorenzo Huipulco, CDMX, 14370, Mexico.
| | - V Alcántara-Alonso
- Molecular Neurophysiology Laboratory, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, Calz. México-Xochimilco No. 101, San Lorenzo Huipulco, CDMX, 14370, Mexico
| | - G Matamoros-Trejo
- Molecular Neurophysiology Laboratory, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, Calz. México-Xochimilco No. 101, San Lorenzo Huipulco, CDMX, 14370, Mexico
| | - M I Amaya
- Molecular Neurophysiology Laboratory, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, Calz. México-Xochimilco No. 101, San Lorenzo Huipulco, CDMX, 14370, Mexico
| | - E Alvarez-Salas
- Molecular Neurophysiology Laboratory, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, Calz. México-Xochimilco No. 101, San Lorenzo Huipulco, CDMX, 14370, Mexico
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Baranowska-Bik A, Bik W. The Association of Obesity with Autoimmune Thyroiditis and Thyroid Function-Possible Mechanisms of Bilateral Interaction. Int J Endocrinol 2020; 2020:8894792. [PMID: 33381173 PMCID: PMC7755496 DOI: 10.1155/2020/8894792] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/28/2020] [Accepted: 12/04/2020] [Indexed: 12/17/2022] Open
Abstract
A growing number of patients suffer from autoimmune diseases, including autoimmune thyroid disease. There has simultaneously been a significant increase in the prevalence of obesity worldwide. It is still an open question whether adiposity can directly influence activation of inflammatory processes affecting the thyroid in genetically predisposed individuals. Adipokines, biologically active substances derived from the adipocytes, belong to a heterogenic group of compounds involved in numerous physiological functions, including the maintenance of metabolism, hormonal balance, and immune response. Notably, the presence of obesity worsens the course of selected autoimmune diseases and impairs response to treatment. Moreover, the excess of body fat may result in the progression of autoimmune diseases. Nutritional status, body weight, and energy expenditure may influence thyroid hormone secretion. Interestingly, thyroid hormones might influence the activity of adipose tissue as metabolic alterations related to fat tissue are observed under pathological conditions in which there are deficits or overproduction of thyroid hormones. Functioning TSH receptors are expressed on adipocytes. Thermogenesis may presumably be stimulated by TSH binding to its receptor on brown adipocytes. There could be a bilateral interaction between the thyroid and adipose. Obesity may influence the onset and course of autoimmune disease.
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Affiliation(s)
- Agnieszka Baranowska-Bik
- Department of Endocrinology, Centre of Postgraduate Medical Education, Ceglowska 80, Warsaw 01-809, Poland
| | - Wojciech Bik
- Department of Neuroendocrinology, Centre of Postgraduate Medical Education, Marymoncka 99/103, Warsaw 01-813, Poland
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Diet-Induced Growth Is Regulated via Acquired Leptin Resistance and Engages a Pomc-Somatostatin-Growth Hormone Circuit. Cell Rep 2019; 23:1728-1741. [PMID: 29742429 PMCID: PMC6015746 DOI: 10.1016/j.celrep.2018.04.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 03/13/2018] [Accepted: 04/02/2018] [Indexed: 02/02/2023] Open
Abstract
Anorexigenic pro-opiomelanocortin (Pomc)/alpha-melanocyte stimulating hormone (αMSH) neurons of the hypothalamic melanocortin system function as key regulators of energy homeostasis, also controlling somatic growth across different species. However, the mechanisms of melanocortin-dependent growth control still remain ill-defined. Here, we reveal a thus-far-unrecognized structural and functional connection between Pomc neurons and the somatotropic hypothalamo-pituitary axis. Excessive feeding of larval zebrafish causes leptin resistance and reduced levels of the hypothalamic satiety mediator pomca. In turn, this leads to reduced activation of hypophysiotropic somatostatin (Sst)-neurons that express the melanocortin receptor Mc4r, elevated growth hormone (GH) expression in the pituitary, and enhanced somatic growth. Mc4r expression and αMSH responsiveness are conserved in Sst-expressing hypothalamic neurons of mice. Thus, acquired leptin resistance and attenuation of pomca transcription in response to excessive caloric intake may represent an ancient mechanism to promote somatic growth when food resources are plentiful.
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15
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Farr OM, Mantzoros CS. Old and new tools to study human brain physiology: Current state, future directions and implications for metabolic regulation. Metabolism 2019; 99:iii-viii. [PMID: 31400385 DOI: 10.1016/j.metabol.2019.153957] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/05/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Olivia M Farr
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215, United States of America.
| | - Christos S Mantzoros
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215, United States of America; Section of Endocrinology, Boston VA Healthcare System/Harvard Medical School, Boston, MA 02130, United States of America
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16
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Relationship of α-MSH and AgRP axons to the perikarya of melanocortin-4 receptor neurons. Brain Res 2019; 1717:136-146. [DOI: 10.1016/j.brainres.2019.04.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 03/29/2019] [Accepted: 04/18/2019] [Indexed: 11/21/2022]
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17
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Marzullo P, Minocci A, Mele C, Fessehatsion R, Tagliaferri M, Pagano L, Scacchi M, Aimaretti G, Sartorio A. The relationship between resting energy expenditure and thyroid hormones in response to short-term weight loss in severe obesity. PLoS One 2018; 13:e0205293. [PMID: 30339686 PMCID: PMC6195261 DOI: 10.1371/journal.pone.0205293] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/21/2018] [Indexed: 02/06/2023] Open
Abstract
Background Regulating thermogenesis is a major task of thyroid hormones (THs), and involves TH-responsive energetic processes at the central and peripheral level. In severe obesity, little is known on the relationship between THs and resting energy expenditure (REE) before and after weight loss. Methods We enrolled 100 euthyroid subjects with severe obesity who were equally distributed between genders. Each was examined before and after completion of a 4-wk inpatient multidisciplinary dieting program and subjected to measurement of thyroid function, REE, fat-free mass (FFM, kg) and percent fat mass (FM). Results Baseline REE was lower than predicted in 70 obese patients, and overall associated with BMI, FFM and FM but not thyroid-related parameters. By the study end, both BMI and REE decreased (5.5% and 4.1%, p<0.001 vs. baseline) and their percent changes were significantly associated (p<0.05), while no association related percent changes of REE and FFM or FM. Individually, REE decreased in 66 and increased in 34 patients irrespective of gender, BMI and body composition. Weight loss significantly impacted TSH (-6.3%), FT3 (-3.3%) and FT4 levels (3.9%; p<0.001 for all). By the study end, a significant correlation became evident between REE and FT4 (r = 0.42, p<0.001) as well as FT3 (r = 0.24, p<0.05). In stepwise multivariable regression analysis, however, neither THs nor body composition entered the regression equation for REE response to weight loss. Conclusions In severe obesity, short-term weight loss discloses a positive relationship between REE and THs.
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Affiliation(s)
- Paolo Marzullo
- IRCCS Istituto Auxologico Italiano, Division of General Medicine, Piancavallo, Verbania, Italy
- Università del Piemonte Orientale, Department of Translational Medicine, Novara, Italy
- * E-mail:
| | - Alessandro Minocci
- IRCCS Istituto Auxologico Italiano, Division of Metabolic Diseases, Piancavallo, Verbania, Italy
| | - Chiara Mele
- IRCCS Istituto Auxologico Italiano, Division of General Medicine, Piancavallo, Verbania, Italy
- Università del Piemonte Orientale, Department of Translational Medicine, Novara, Italy
| | - Rezene Fessehatsion
- IRCCS Istituto Auxologico Italiano, Division of Metabolic Diseases, Piancavallo, Verbania, Italy
| | | | - Loredana Pagano
- University of Turin, Department of Medical Sciences, Turin, Italy
| | - Massimo Scacchi
- IRCCS Istituto Auxologico Italiano, Division of General Medicine, Piancavallo, Verbania, Italy
- University of Milan, Department of Clinical Sciences and Community Health, Milan, Italy
| | - Gianluca Aimaretti
- Università del Piemonte Orientale, Department of Translational Medicine, Novara, Italy
| | - Alessandro Sartorio
- IRCCS Istituto Auxologico Italiano, Division of Metabolic Diseases, Piancavallo, Verbania, Italy
- IRCCS Istituto Auxologico Italiano, Experimental Laboratory for Auxo-Endocrinological Research, Piancavallo, Verbania, Italy
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Timper K, Brüning JC. Hypothalamic circuits regulating appetite and energy homeostasis: pathways to obesity. Dis Model Mech 2018; 10:679-689. [PMID: 28592656 PMCID: PMC5483000 DOI: 10.1242/dmm.026609] [Citation(s) in RCA: 445] [Impact Index Per Article: 74.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The ‘obesity epidemic’ represents a major global socioeconomic burden that urgently calls for a better understanding of the underlying causes of increased weight gain and its associated metabolic comorbidities, such as type 2 diabetes mellitus and cardiovascular diseases. Improving our understanding of the cellular basis of obesity could set the stage for the development of new therapeutic strategies. The CNS plays a pivotal role in the regulation of energy and glucose homeostasis. Distinct neuronal cell populations, particularly within the arcuate nucleus of the hypothalamus, sense the nutrient status of the organism and integrate signals from peripheral hormones including pancreas-derived insulin and adipocyte-derived leptin to regulate calorie intake, glucose metabolism and energy expenditure. The arcuate neurons are tightly connected to other specialized neuronal subpopulations within the hypothalamus, but also to various extrahypothalamic brain regions, allowing a coordinated behavioral response. This At a Glance article gives an overview of the recent knowledge, mainly derived from rodent models, regarding the CNS-dependent regulation of energy and glucose homeostasis, and illustrates how dysregulation of the neuronal networks involved can lead to overnutrition and obesity. The potential impact of recent research findings in the field on therapeutic treatment strategies for human obesity is also discussed. Summary: This at a glance article gives an overview of the recent knowledge mainly derived from rodent models regarding the CNS-dependent regulation of energy and glucose homeostasis, and depicts how dysregulation of the involved neuronal networks promotes overnutrition and obesity.
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Affiliation(s)
- Katharina Timper
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, Cologne 50931, Germany.,Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, Cologne 50924, Germany.,Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, Cologne 50931, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, Cologne 50931, Germany .,Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, Cologne 50924, Germany.,Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, Cologne 50931, Germany.,National Center for Diabetes Research (DZD), Ingolstädter Land Str. 1, Neuherberg 85764, Germany
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Dimić D, Velojić - Golubović M, Radenković S. THE CORRELATION BETW EEN BODY MASS INDEX AND THYROID STIMULATING HORMONE IN EUTHYROID PERSONS. ACTA MEDICA MEDIANAE 2018. [DOI: 10.5633/amm.2018.0105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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20
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Çetinkaya S, Güran T, Kurnaz E, Keskin M, Sağsak E, Savaş Erdeve S, Suntharalingham JP, Buonocore F, Achermann JC, Aycan Z. A Patient with Proopiomelanocortin Deficiency: An Increasingly Important Diagnosis to Make. J Clin Res Pediatr Endocrinol 2018; 10:68-73. [PMID: 28739551 PMCID: PMC5838375 DOI: 10.4274/jcrpe.4638] [Citation(s) in RCA: 12] [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] [Indexed: 12/01/2022] Open
Abstract
Proopiomelanocortin (POMC) deficiency is a rare monogenic disorder with early-onset obesity. Investigation of this entity have increased our insight into the important role of the leptin-melanocortin pathway in energy balance. Here, we present a patient with POMC deficiency due to a homozygous c.206delC mutation in the POMC gene. We discuss the pathogenesis of this condition with emphasis on the crosstalk between hypothalamic and peripheral signals in the development of obesity and the POMC-melanocortin 4 receptors system as a target for therapeutic intervention.
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Affiliation(s)
- Semra Çetinkaya
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey,* Address for Correspondence: University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey GSM: +90 312 305 65 08 E-mail:
| | - Tülay Güran
- Marmara University Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Erdal Kurnaz
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Melikşah Keskin
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Elif Sağsak
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | - Senay Savaş Erdeve
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey
| | | | - Federica Buonocore
- University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - John C. Achermann
- University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Zehra Aycan
- University of Health Sciences, Dr. Sami Ulus Training and Research Hospital, Clinic of Children’s Health and Disease, Health Implementation and Research Center, Ankara, Turkey,Yıldırım Beyazıt University Faculty of Medicine, Department of Pediatric Endocrinology, Ankara, Turkey
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21
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Parlak N, Görgülü Y, Köse Çinar R, Sönmez MB, Parlak E. Serum agouti-related protein (AgRP) levels in bipolar disorder: Could AgRP be a state marker for mania? Psychiatry Res 2018; 260:36-40. [PMID: 29172096 DOI: 10.1016/j.psychres.2017.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 08/21/2017] [Accepted: 11/04/2017] [Indexed: 11/28/2022]
Abstract
Orexigenic and anorexigenic peptides, especially agouti-related protein (AgRP) and leptin, play important roles in the regulation of energy homeostasis in bipolar disorder. AgRP regulates energy metabolism by increasing appetite and decreasing energy expenditure. The resting energy expenditures of patients with manic bipolar disorder are higher than those of controls. Due to the effects of AgRP on energy expenditure and the increased physical activity of manic patients, we hypothesised that serum AgRP levels may be lower in manic patients than in euthymic patients and controls. There was a total of 112 participants, including 47 patients in the manic group, 35 patients in the euthymic group and 30 healthy controls. For this study, serum AgRP, leptin, cholesterol, and cortisol levels were measured and compared between the groups. The serum AgRP, leptin, and cholesterol levels were significantly different between the groups. The serum AgRP levels of manic group were significantly lower than those of euthymic and control groups. The lower serum AgRP levels of manic patients could be indicators of impaired energy homeostasis during manic episodes. Since the serum AgRP levels of manic patients are lower than those of euthymic patients and controls, AgRP could be a state marker for manic episodes.
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Affiliation(s)
- Naci Parlak
- Department of Psychiatry, Izzet Baysal Mental Health and Disease Training and Research Hospital, Bolu 14030, Turkey.
| | - Yasemin Görgülü
- Department of Psychiatry, Trakya University Faculty of Medicine, Edirne 22030, Turkey.
| | - Rugül Köse Çinar
- Department of Psychiatry, Trakya University Faculty of Medicine, Edirne 22030, Turkey.
| | - Mehmet Bülent Sönmez
- Department of Psychiatry, Trakya University Faculty of Medicine, Edirne 22030, Turkey.
| | - Ebru Parlak
- Department of Psychiatry, Izzet Baysal Mental Health and Disease Training and Research Hospital, Bolu 14030, Turkey.
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22
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García-Luna C, Soberanes-Chávez P, de Gortari P. Impaired hypothalamic cocaine- and amphetamine-regulated transcript expression in lateral hypothalamic area and paraventricular nuclei of dehydration-induced anorexic rats. J Neuroendocrinol 2017; 29. [PMID: 28984394 DOI: 10.1111/jne.12541] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/14/2017] [Accepted: 10/02/2017] [Indexed: 11/28/2022]
Abstract
Negative energy balance promotes physiological adaptations that ensure the survival of animals. The hypothalamic-pituitary-thyroid axis regulates basal energy expenditure and its down-regulating adaptation to negative energy balance is well described: in fasting, the serum content of thyrotrophin (TSH) and thyroid hormones (TH) decreases, enhancing the survival odds of individuals. By contrast, dehydration-induced anorexic (DIA) rats present an impaired hypothalamic-pituitary-thyroid (HPT) axis adaptation despite their negative energy balance: increased circulating TSH levels. The implication of cocaine- and amphetamine-regulated transcript (CART), an anorexic peptide, in HPT axis function impairment and food-avoidance behaviour displayed by DIA animals is unknown. Because CART is co-expressed with the peptide that regulates the HPT axis in hypophysiotrophic paraventricular nucleus (PVN) neurones (TSH-releasing hormone), we analysed CART expression and possible implications with respect to high TSH levels of DIA animals. We examined whether changes in CART expression from the lateral hypothalamic area (LHA) and arcuate nucleus (ARC) could participate in food-avoidance of DIA rats. DIA and forced-food restricted (FFR) animals reduced their body weight and food intake. FFR rats had a down-regulation of their HPT axis (reduced serum TH and TSH content), whereas DIA animals had reduced TH but increased TSH levels. CART mRNA expression in the ARC decreased similarly between experimental groups and diminished in anterior, medial PVN and in LHA of FFR animals, whereas DIA animals showed unchanged levels. This impaired CART mRNA expression in the anterior PVN and LHA could be related to the aberrant feeding behaviour of DIA rats but not to their deregulated HPT axis function.
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Affiliation(s)
- C García-Luna
- Molecular Neurophysiology Laboratory, Department of Neurosciences Research, National Institute of Psychiatry Ramón de la Fuente Muñiz, Mexico City, Mexico
| | - P Soberanes-Chávez
- Molecular Neurophysiology Laboratory, Department of Neurosciences Research, National Institute of Psychiatry Ramón de la Fuente Muñiz, Mexico City, Mexico
| | - P de Gortari
- Molecular Neurophysiology Laboratory, Department of Neurosciences Research, National Institute of Psychiatry Ramón de la Fuente Muñiz, Mexico City, Mexico
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24
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Ramos-Lobo AM, Donato J. The role of leptin in health and disease. Temperature (Austin) 2017; 4:258-291. [PMID: 28944270 DOI: 10.1080/23328940.2017.1327003] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/27/2017] [Accepted: 05/02/2017] [Indexed: 02/07/2023] Open
Abstract
Leptin is a master regulator of energy balance and body adiposity. Additionally, leptin exerts important control on glucose homeostasis, thermogenesis, autonomic nervous system and neuroendocrine axes. In metabolic diseases, such as obesity and diabetes mellitus, leptin signaling may be compromised, indicating the important role of this hormone in the etiology and pathophysiological manifestations of these conditions. In the present manuscript, we reviewed important concepts of leptin signaling, as well as about the effects of leptin on several biologic functions. We also discussed the possible therapeutic use of leptin administration and how our current obesogenic environment contributes to the development of leptin resistance. Our objective was to provide a comprehensive and state-of-the-art review about the importance of leptin to maintain the homeostasis and during pathological conditions.
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Affiliation(s)
- Angela M Ramos-Lobo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
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25
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Cote-Vélez A, Martínez Báez A, Lezama L, Uribe RM, Joseph-Bravo P, Charli JL. A screen for modulators reveals that orexin-A rapidly stimulates thyrotropin releasing hormone expression and release in hypothalamic cell culture. Neuropeptides 2017; 62:11-20. [PMID: 28173961 DOI: 10.1016/j.npep.2017.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/25/2017] [Accepted: 01/30/2017] [Indexed: 12/21/2022]
Abstract
In the paraventricular nucleus of the mammalian hypothalamus, hypophysiotropic thyrotropin releasing hormone (TRH) neurons integrate metabolic information and control the activity of the thyroid axis. Additional populations of TRH neurons reside in various hypothalamic areas, with poorly defined connections and functions, albeit there is evidence that some may be related to energy balance. To establish extracellular modulators of TRH hypothalamic neurons activity, we performed a screen of neurotransmitters effects in hypothalamic cultures. Cell culture conditions were chosen to facilitate the full differentiation of the TRH neurons; these conditions had permitted the characterization of the effects of known modulators of hypophysiotropic TRH neurons. The major end-point of the screen was Trh mRNA levels, since they are generally rapidly (0.5-3h) modified by synaptic inputs onto TRH neurons; in some experiments, TRH cell content or release was also analyzed. Various modulators, including histamine, serotonin, β-endorphin, met-enkephalin, and melanin concentrating hormone, had no effect. Glutamate, as well as ionotropic agonists (kainate and N-Methyl-d-aspartic acid), increased Trh mRNA levels. Baclofen, a GABAB receptor agonist, and dopamine enhanced Trh mRNA levels. An endocannabinoid receptor 1 inverse agonist promoted TRH release. Somatostatin increased Trh mRNA levels and TRH cell content. Orexin-A rapidly increased Trh mRNA levels, TRH cell content and release, while orexin-B decreased Trh mRNA levels. These data reveal unaccounted regulators, which exert potent effects on hypothalamic TRH neurons in vitro.
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Affiliation(s)
- Antonieta Cote-Vélez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Anabel Martínez Báez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Leticia Lezama
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Rosa María Uribe
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Patricia Joseph-Bravo
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Jean-Louis Charli
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico.
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Valdés-Moreno MI, Alcántara-Alonso V, Estrada-Camarena E, Mengod G, Amaya MI, Matamoros-Trejo G, de Gortari P. Phosphodiesterase-7 inhibition affects accumbal and hypothalamic thyrotropin-releasing hormone expression, feeding and anxiety behavior of rats. Behav Brain Res 2017; 319:165-173. [PMID: 27864049 DOI: 10.1016/j.bbr.2016.11.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/24/2016] [Accepted: 11/14/2016] [Indexed: 12/19/2022]
Abstract
Thyrotropin-releasing hormone (TRH) has anorexigenic and anxiolytic functions when injected intraventricularly. Nucleus accumbens (NAcc) is a possible brain region involved, since it expresses proTRH. TRH from hypothalamic paraventricular nucleus (PVN) has a food intake-regulating role. TRHergic pathways of NAcc and PVN are implicated in anxiety and feeding. Both behaviors depend on cAMP and phosphorylated-cAMP response element binding protein (pCREB) intracellular levels. Intracellular levels of cAMP are controlled by the degrading activity of phosphodiesterases (PDEs). Since TRH transcription is activated by pCREB, a specific inhibitor of PDE7B may regulate TRH-induced effects on anxiety and feeding. We evaluated the effectiveness of an intra-accumbal and intraperitoneal (i.p.) administration of a PDE7 inhibitor (BRL-50481) on rats' anxiety-like behavior and food intake; also on TRH mRNA and protein expression in NAcc and PVN to define its mediating role on the PDE7 inhibitor-induced behavioral changes. Accumbal injection of 4μg/0.3μL of PDE7 inhibitor decreased rats' anxiety. The i.p. injection of 0.2mg/kg of the inhibitor was able to increase the PVN TRH mRNA expression and to decrease feeding but did not change animals' anxiety levels; in contrast, 2mg/kg b.w inhibitor enhanced accumbal TRH mRNA, induced anxiolysis with no change in food intake. PDE7 inhibitor induced anxiolytic and anorexigenic like behavior depending on the dose used. Results supported hypothalamic TRH mediated feeding-reduction effects, and accumbal TRH mediation of inhibitor-induced anxiolysis. Thus, an i.p dose of this inhibitor might be reducing anxiety with no change in feeding, which could be useful for obese patients.
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Affiliation(s)
- M I Valdés-Moreno
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico; School of Dietetics and Nutrition ISSSTE, Callejón Vía San Fernando 12, Col. San Pedro Apóstol, 14070 México City, Mexico
| | - V Alcántara-Alonso
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - E Estrada-Camarena
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - G Mengod
- Department of Neurochemistry and Neuropharmachology, Institut d'Investigacions Biòmediques de Barcelona, CSIC, IDIBAPS, CIBERNED, c/Rosselló 161, 6a, E 08036 Barcelona, Spain
| | - M I Amaya
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - G Matamoros-Trejo
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - P de Gortari
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico.
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Hill JW, Faulkner LD. The Role of the Melanocortin System in Metabolic Disease: New Developments and Advances. Neuroendocrinology 2017; 104:330-346. [PMID: 27728914 PMCID: PMC5724371 DOI: 10.1159/000450649] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/01/2016] [Indexed: 12/17/2022]
Abstract
Obesity is increasing in prevalence across all sectors of society, and with it a constellation of associated ailments including hypertension, type 2 diabetes, and eating disorders. The melanocortin system is a critical neural system underlying the control of body weight and other functions. Deficits in the melanocortin system may promote or exacerbate the comorbidities of obesity. This system has therefore generated great interest as a potential target for treatment of obesity. However, drugs targeting melanocortin receptors are plagued by problematic side effects, including undesirable increases in sympathetic nervous system activity, heart rate, and blood pressure. Circumnavigating this roadblock will require a clearer picture of the precise neural circuits that mediate the functions of melanocortins. Recent, novel experimental approaches have significantly advanced our understanding of these pathways. We here review the latest advances in our understanding of the role of melanocortins in food intake, reward pathways, blood pressure, glucose control, and energy expenditure. The evidence suggests that downstream melanocortin-responsive circuits responsible for different physiological actions do diverge. Ultimately, a more complete understanding of melanocortin pathways and their myriad roles should allow treatments tailored to the mix of metabolic disorders in the individual patient.
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Affiliation(s)
- Jennifer W Hill
- Department of Physiology and Pharmacology, College of Medicine, The University of Toledo, Toledo, OH, USA
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Ortiga-Carvalho TM, Oliveira KDJ, Morales MM, Martins VP, Pazos-Moura CC. Thyrotropin Secretagogues Reduce Rat Pituitary Neuromedin B, a Local Thyrotropin Release Inhibitor. Exp Biol Med (Maywood) 2016; 228:1083-8. [PMID: 14530520 DOI: 10.1177/153537020322800916] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Neuromedin B (NB), a bombesin-like peptide, highly concentrated in rat pituitary gland, has been shown to act as an autocrine/paracrine inhibitor of thyrotropin (TSH) release. Here it is shown that a single injection of thyrotropin-releasing hormone (TRH, 1.5 μg/animal, Ip), the most important stimulator of thyrotropin secretion, induced approximately 35%–45% decrease in pituitary NB content in rats, as well as an important decrease in NB mRNA at 15 and 30 min ( P < 0.05). Acute cold exposure, which induced higher serum TSH with a peak at 30 min, was associated with progressive decrease in pituitary NB, starting at 15 min although only reaching statistical significance after 2 hr ( P < 0.05). Although not involved in the early peak, the decrease in NB may be contributing to maintenance of higher serum TSH in cold-exposed animals compared with those at room temperature. Fed rats, 2 hr after being subcutaneously injected with mouse recombinant leptin (8 μg /100 g body wt), showed a ×2 increase in serum TSH and 38% reduction in pituitary NB ( P < 0.05). In conclusion, TRH and leptin rapidly decreased pituitary NB and it is first proposed that the reduction of the inhibitory tonus of NB on TSH release will ultimately contribute to the amplification of TSH secretion elicited by TSH secretagogues.
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Affiliation(s)
- Tânia Maria Ortiga-Carvalho
- Laboratório de Endocrinologia Molecular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, CCS-Cidade Universitária, Ilha do Fundão, Rio de Janeiro, Brasil
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α-MSH and Foxc2 promote fatty acid oxidation through C/EBPβ negative transcription in mice adipose tissue. Sci Rep 2016; 6:36661. [PMID: 27819350 PMCID: PMC5098202 DOI: 10.1038/srep36661] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/18/2016] [Indexed: 01/18/2023] Open
Abstract
Alpha melanocyte stimulating hormone (α-MSH) and Forkhead box C2 protein (Foxc2) enhance lipolysis in multiple tissues. However, their relationship in adipose fatty acid oxidation (FAO) remains unclear. Here, we demonstrated that α-MSH and Foxc2 increased palmitate oxidation to CO2 in white (WAT) and brown adipose tissue (BAT). C/EBPβ expression was reduced by α-MSH and Foxc2. FFA level was elevated by α-MSH and pc-Foxc2 treatment along with increased FAO in white and brown adipocytes. The expression of FAO key enzymes, medium-chain acyl-CoA dehydrogenase (MCAD) and long-chain acyl-CoA dehydrogenase (LCAD) were increased in α-MSH and pc-Foxc2 group. Combination of α-MSH and Foxc2 treatment synergistically promoted FAO through increasing the activity of CPT-1 and phosphorylation of ACC. We found C/EBPβ bind to MC5R and Foxc2 promoter regions and inhibited FAO. cAMP level was increased by α-MSH and Foxc2 individually treated or combined treatment. Furthermore, cAMP/PKA pathway-specific inhibitor (H89) blocked the FAO, despite in α-MSH and Foxc2 both added group. While forskolin, the cAMP agonist, promoted FAO and enhanced the effect of α-MSH and Foxc2. Collectively, α-MSH and Foxc2 mutual promote FAO in WAT and BAT via cAMP/PKA signal pathway. And C/EBPβ as a transcription suppressor inhibits α-MSH and Foxc2 expression and FAO.
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Gan L, Liu Z, Wu T, Feng F, Sun C. αMSH promotes preadipocyte proliferation by alleviating ER stress-induced leptin resistance and by activating Notch1 signal in mice. Biochim Biophys Acta Mol Basis Dis 2016; 1863:231-238. [PMID: 27717825 DOI: 10.1016/j.bbadis.2016.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/24/2016] [Accepted: 10/03/2016] [Indexed: 01/17/2023]
Abstract
Alpha-melanocyte stimulating hormone (αMSH) has an important role in the regulation of body weight and energy expenditure. Nevertheless, the molecular mechanisms of circulating αMSH on preadipocyte proliferation remain elusive. We found αMSH was reduced by high fat diet (HFD) while leptin was elevated in adipose tissue. Leptin resistance and endoplasmic reticulum (ER) stress of adipose tissue were increased in obese mice. αMSH increased leptin sensitivity and alleviated ER stress along with increased p-STAT3 level and reduced SOCS3, GRP78, CHOP, ATF4, p27 and p53 levels. αMSH and leptin co-treatment alleviated ER stress through decreasing the levels of GRP78 and CHOP. Tunicamycin (TM) or thapsigargin (Tg) induced ER stress blunted leptin sensitivity and inhibited preadipocyte proliferation. αMSH and leptin co-treatment increased the cell number, augmented G1-S transition, elevated leptin sensitivity, and reduced ER stress; it also activated Notch1 signal and stimulated preadipocyte proliferation, whereas ER stress marker genes were decreased during this process. However, the effects of αMSH and leptin were blocked by the specific inhibitor of Notch1 signal. In summary, our data revealed αMSH enhanced leptin sensitivity and preadipocyte proliferation, meanwhile inhibited ER stress of preadipocytes by activating Notch1 signal.
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Affiliation(s)
- Lu Gan
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zhenjiang Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Tianjiao Wu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fei Feng
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Chao Sun
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
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Bradnová O, Vejražková D, Vaňková M, Lukášová P, Včelák J, Stanická S, Dvořáková K, Bendlová B. Metabolic and hormonal consequencies of the "obesity risk" MC4R variant (rs12970134) in Czech women. Physiol Res 2016; 64:S187-95. [PMID: 26680479 DOI: 10.33549/physiolres.933119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Although the mutations in MC4R gene became known as the most common genetic cause of human obesity, the effect of rs12970134 A/G near MC4R gene on insulin resistance has been described. The aim of this study was to determine the effect of rs12970134 on obesity, hormone levels, and glucose metabolism in a cohort of women varying in glucose tolerance: 850 normoglycemic women, 423 diagnosed with polycystic ovary syndrome (PCOS), 402 gestational diabetics (GDM), and 250 type 2 diabetic (T2D) women. We did not confirm the explicit effect of rs12970134 on obesity. However, the influence of the A-allele on body adiposity index was observed in a cohort of women diagnosed with PCOS. In normoglycemic women, the A-allele carriership was associated with lower fasting levels of glucose, insulin, C-peptide, and index of insulin resistance. Furthermore, higher levels of growth hormone, leptin and SHBG, and lower levels of fT3, testosterone, and androstenedione were recorded in normoglycemic A-allele carriers. In conclusion, the study presents the evidence of the impact of rs12970134 on complex hypothalamic regulations.
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Affiliation(s)
- O Bradnová
- Department of Molecular Endocrinology, Institute of Endocrinology, Prague, Czech Republic.
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Leptin receptor-positive and leptin receptor-negative proopiomelanocortin neurons innervate an identical set of brain structures. Brain Res 2016; 1646:366-376. [DOI: 10.1016/j.brainres.2016.06.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 06/01/2016] [Accepted: 06/15/2016] [Indexed: 11/21/2022]
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Messina A, De Fusco C, Monda V, Esposito M, Moscatelli F, Valenzano A, Carotenuto M, Viggiano E, Chieffi S, De Luca V, Cibelli G, Monda M, Messina G. Role of the Orexin System on the Hypothalamus-Pituitary-Thyroid Axis. Front Neural Circuits 2016; 10:66. [PMID: 27610076 PMCID: PMC4997012 DOI: 10.3389/fncir.2016.00066] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Accepted: 08/08/2016] [Indexed: 12/25/2022] Open
Abstract
Hypocretin/orexin (ORX) are two hypothalamic neuropeptides discovered in 1998. Since their discovery, they have been one of the most studied neuropeptide systems because of their projecting fields innervating various brain areas. The orexinergic system is tied to sleep-wakefulness cycle, and narcolepsy is a consequence of their system hypofunction. Orexinergic system is also involved in many other autonomic functions such as feeding, thermoregulation, cardiovascular and neuroendocrine regulation. The main aim of this mini review article is to investigate the relationship between ORX and thyroid system regulation. Although knowledge about the ORX system is evolving, its putative effects on hypothalamic-pituitary-thyroid (HPT) axis still appear unclear. We analyzed some studies about ORX control of HPT axis to know better the relationship between them. The studies that were analyzed suggest Hypocretin/ORX to modulate the thyroid regulation, but the nature (excitatory or inhibitory) of this possible interaction remains actually unclear and needs to be confirmed.
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Affiliation(s)
- Antonietta Messina
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Carolina De Fusco
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Vincenzo Monda
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Maria Esposito
- Neapolitan Brain Group (NBG), Clinic of Child and Adolescent Neuropsychiatry, Department of Mental, Physical Health and Preventive Medicine, Second University of Naples Naples, Italy
| | - Fiorenzo Moscatelli
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Anna Valenzano
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Marco Carotenuto
- Neapolitan Brain Group (NBG), Clinic of Child and Adolescent Neuropsychiatry, Department of Mental, Physical Health and Preventive Medicine, Second University of Naples Naples, Italy
| | - Emanuela Viggiano
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Sergio Chieffi
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Vincenzo De Luca
- Department of Psychiatry, University of Toronto Toronto, ON, Canada
| | - Giuseppe Cibelli
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Marcellino Monda
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of Naples Naples, Italy
| | - Giovanni Messina
- Department of Experimental Medicine, Section of Human Physiology and Unit of Dietetic and Sport Medicine, Second University of NaplesNaples, Italy; Department of Clinical and Experimental Medicine, University of FoggiaFoggia, Italy
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Shpakov AO. The brain leptin signaling system and its functional state in metabolic syndrome and type 2 diabetes mellitus. J EVOL BIOCHEM PHYS+ 2016. [DOI: 10.1134/s0022093016030017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Derkach KV, Moiseyuk IV, Shpakova EA, Shpakov AO. The thyroid status of rats immunized with peptides derived from the extracellular regions of the types 3 and 4 melanocortin receptors and the 1B-subtype 5-hydroxytryptamine receptor. J EVOL BIOCHEM PHYS+ 2015. [DOI: 10.1134/s0022093015040031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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36
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Long-term hyperphagia and caloric restriction caused by low- or high-density husbandry have differential effects on zebrafish postembryonic development, somatic growth, fat accumulation and reproduction. PLoS One 2015; 10:e0120776. [PMID: 25799180 PMCID: PMC4370574 DOI: 10.1371/journal.pone.0120776] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 01/29/2015] [Indexed: 12/19/2022] Open
Abstract
In recent years, the zebrafish (Danio rerio) has emerged as an alternative vertebrate model for energy homeostasis and metabolic diseases, including obesity and anorexia. It has been shown that diet-induced obesity (DIO) in zebrafish shares multiple pathophysiological features with obesity in mammals. However, a systematic and comprehensive analysis of the different pathways of energy expenditure in obese and starved fish had been missing thus far. Here, we carry out long-term ad libitum feeding (hyperphagia) and caloric restriction studies induced by low- or high-density husbandry, respectively, to investigate the impact of caloric intake on the timing of scale formation, a crucial step of postembryonic development and metamorphosis, and on somatic growth, body weight, fat storage and female reproduction. We show that all of them are positively affected by increased caloric intake, that middle-aged fish develop severe DIO, and that the body mass index (BMI) displays a strict linear correlation with whole-body triglyceride levels in adult zebrafish. Interestingly, juvenile fish are largely resistant to DIO, while BMI and triglyceride values drop in aged fish, pointing to aging-associated anorexic effects. Histological analyses further indicate that increased fat storage in white adipose tissue involves both hyperplasia and hypertrophy of adipocytes. Furthermore, in ovaries, caloric intake primarily affects the rate of oocyte growth, rather than total oocyte numbers. Finally, comparing the different pathways of energy expenditure with each other, we demonstrate that they are differentially affected by caloric restriction / high-density husbandry. In juvenile fish, scale formation is prioritized over somatic growth, while in sexually mature adults, female reproduction is prioritized over somatic growth, and somatic growth over fat storage. Our data will serve as a template for future functional studies to dissect the neuroendocrine regulators of energy homeostasis mediating differential energy allocation.
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Drougard A, Fournel A, Valet P, Knauf C. Impact of hypothalamic reactive oxygen species in the regulation of energy metabolism and food intake. Front Neurosci 2015; 9:56. [PMID: 25759638 PMCID: PMC4338676 DOI: 10.3389/fnins.2015.00056] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/07/2015] [Indexed: 12/31/2022] Open
Abstract
Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites) from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS) as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC) and agouti-related protein (AgRP)/neuropeptide Y (NPY) neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,…), neurotransmitters and nutrients (glucose, lipids,…). The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes. In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.
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Affiliation(s)
- Anne Drougard
- NeuroMicrobiota, European Associated Laboratory, INSERM/UCL, Institut National de la Santé et de la Recherche Médicale, U1048, Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), CHU Rangueil, Université Paul SabatierToulouse, France
| | | | | | - Claude Knauf
- NeuroMicrobiota, European Associated Laboratory, INSERM/UCL, Institut National de la Santé et de la Recherche Médicale, U1048, Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), CHU Rangueil, Université Paul SabatierToulouse, France
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Wellhauser L, Gojska NM, Belsham DD. Delineating the regulation of energy homeostasis using hypothalamic cell models. Front Neuroendocrinol 2015; 36:130-49. [PMID: 25223866 DOI: 10.1016/j.yfrne.2014.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 08/28/2014] [Accepted: 09/02/2014] [Indexed: 12/27/2022]
Abstract
Attesting to its intimate peripheral connections, hypothalamic neurons integrate nutritional and hormonal cues to effectively manage energy homeostasis according to the overall status of the system. Extensive progress in the identification of essential transcriptional and post-translational mechanisms regulating the controlled expression and actions of hypothalamic neuropeptides has been identified through the use of animal and cell models. This review will introduce the basic techniques of hypothalamic investigation both in vivo and in vitro and will briefly highlight the key advantages and challenges of their use. Further emphasis will be place on the use of immortalized models of hypothalamic neurons for in vitro study of feeding regulation, with a particular focus on cell lines proving themselves most fruitful in deciphering fundamental basics of NPY/AgRP, Proglucagon, and POMC neuropeptide function.
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Affiliation(s)
- Leigh Wellhauser
- Department of Physiology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
| | - Nicole M Gojska
- Department of Physiology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
| | - Denise D Belsham
- Departments of Physiology, Medicine and OB/GYN, University of Toronto, Toronto, Ontario M5G 1A8, Canada; Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario M5S 1A8, Canada.
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Kordi F, Khazali H. The effect of ghrelin and estradiol on mean concentration of thyroid hormones. Int J Endocrinol Metab 2015; 13:e17988. [PMID: 25745491 PMCID: PMC4338654 DOI: 10.5812/ijem.17988] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 08/04/2014] [Accepted: 09/29/2014] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Ghrelin is a novel peptide hormone that has GH releasing activity and also other endocrine and metabolic functions. It can also increase food intake and decrease T3 and T4 concentrations. Several parameters of hypothalamic-pituitary-thyroid (HPT) axis function are modulated by 17β-estradiol (E2). OBJECTIVES The purpose of this study was to investigate the effect of interactions between ghrelin and estradiol (injected via ICV route) on plasma T3 and T4 concentrations in female rats. MATERIALS AND METHODS Eighteen Wistar female rats (bodyweight, 200-250 g) were randomly divided into three groups. Group 1 received estradiol, Group 2 received ghrelin and Group 3 received ghrelin and estradiol. Plasma samples were used to assess T3 and T4 concentration by RIA. RESULTS The results indicated that ghrelin significantly decreased thyroid hormone concentrations, whereas estradiol increased these concentrations. The simultaneous injection of ghrelin and estradiol significantly decreased the inhibitory effect of ghrelin on thyroid hormone concentrations (P < 0.05). CONCLUSIONS According to the results of this study, both ghrelin and estradiol affect the concentration of thyroid hormone but in opposite directions. This difference might be due to different underlying hormonal mechanisms such as HPA and/or HPT axis melanocyte stimulating hormone (MSH) systems could be suggested.
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Affiliation(s)
- Fatemeh Kordi
- Department of Physiology, Shahid Beheshti University, Tehran, IR Iran
| | - Homayoun Khazali
- Department of Physiology, Shahid Beheshti University, Tehran, IR Iran
- Corresponding author: Homayoun Khazali, Department of Physiology, Shahid Beheshti University, Tehran, IR Iran. Tel: +98-9121254041, E-mail:
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Bétry C, Challan-Belval MA, Bernard A, Charrié A, Drai J, Laville M, Thivolet C, Disse E. Increased TSH in obesity: Evidence for a BMI-independent association with leptin. DIABETES & METABOLISM 2014; 41:248-51. [PMID: 25541439 DOI: 10.1016/j.diabet.2014.11.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/21/2014] [Accepted: 11/24/2014] [Indexed: 01/11/2023]
Abstract
AIM This study aimed to determine whether the association between thyroid-stimulating hormone (TSH) and body mass index (BMI) is related to leptin concentration in obese individuals. METHODS Plasma TSH and leptin assays were performed in 800 consecutive patients, hospitalized for a nutritional checkup, with a BMI ≥ 30 kg/m(2). Various anthropometric, hormonal and metabolic parameters, including age, weight, BMI, insulin, leptin and TSH, were measured or calculated. Univariate and multivariate regression analyses were performed to identify any significant relationships between these parameters. Also, characteristics of the patients in the lowest and highest quartiles of TSH distribution were compared. RESULTS TSH was positively correlated with both BMI and leptin. When multiple regression analysis was performed, TSH and leptin maintained a significant association independent of BMI. Patients in the fourth quartile of TSH distribution displayed higher BMI and higher leptin levels in comparison to the first quartile. CONCLUSION Our study has confirmed an increase in TSH in conjunction with BMI in obese subjects. This increase was correlated with leptin independently of BMI. It is hypothesized that the increase in TSH observed in obese subjects was the consequence of both fat mass accumulation and a positive energy-balance.
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Affiliation(s)
- C Bétry
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - M A Challan-Belval
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - A Bernard
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - A Charrié
- Department of Biochemistry, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France; Centre Européen pour la Nutrition et la Santé (CENS), Centre de Recherche en Nutrition Humaine Rhône-Alpes, Unité INSERM 1060, laboratoire CARMEN, Université Claude-Bernard Lyon 1, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - J Drai
- Department of Biochemistry, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France; Centre Européen pour la Nutrition et la Santé (CENS), Centre de Recherche en Nutrition Humaine Rhône-Alpes, Unité INSERM 1060, laboratoire CARMEN, Université Claude-Bernard Lyon 1, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - M Laville
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France; Centre Européen pour la Nutrition et la Santé (CENS), Centre de Recherche en Nutrition Humaine Rhône-Alpes, Unité INSERM 1060, laboratoire CARMEN, Université Claude-Bernard Lyon 1, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - C Thivolet
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France; Centre Européen pour la Nutrition et la Santé (CENS), Centre de Recherche en Nutrition Humaine Rhône-Alpes, Unité INSERM 1060, laboratoire CARMEN, Université Claude-Bernard Lyon 1, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France
| | - E Disse
- Department of Endocrinology, Diabetes and Nutrition, Specialized and Integrated Center for Obesity Management, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France; Centre Européen pour la Nutrition et la Santé (CENS), Centre de Recherche en Nutrition Humaine Rhône-Alpes, Unité INSERM 1060, laboratoire CARMEN, Université Claude-Bernard Lyon 1, 165, chemin du Grand-Revoyet, 69530 Pierre-Bénite, France.
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Hussain S, Richardson E, Ma Y, Holton C, De Backer I, Buckley N, Dhillo W, Bewick G, Zhang S, Carling D, Bloom S, Gardiner J. Glucokinase activity in the arcuate nucleus regulates glucose intake. J Clin Invest 2014; 125:337-49. [PMID: 25485685 DOI: 10.1172/jci77172] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 11/06/2014] [Indexed: 01/21/2023] Open
Abstract
The brain relies on a constant supply of glucose, its primary fuel, for optimal function. A taste-independent mechanism within the CNS that promotes glucose delivery to the brain has been postulated to maintain glucose homeostasis; however, evidence for such a mechanism is lacking. Here, we determined that glucokinase activity within the hypothalamic arcuate nucleus is involved in regulation of dietary glucose intake. In fasted rats, glucokinase activity was specifically increased in the arcuate nucleus but not other regions of the hypothalamus. Moreover, pharmacologic and genetic activation of glucokinase in the arcuate nucleus of rodent models increased glucose ingestion, while decreased arcuate nucleus glucokinase activity reduced glucose intake. Pharmacologic targeting of potential downstream glucokinase effectors revealed that ATP-sensitive potassium channel and P/Q calcium channel activity are required for glucokinase-mediated glucose intake. Additionally, altered glucokinase activity affected release of the orexigenic neurotransmitter neuropeptide Y in response to glucose. Together, our results suggest that glucokinase activity in the arcuate nucleus specifically regulates glucose intake and that appetite for glucose is an important driver of overall food intake. Arcuate nucleus glucokinase activation may represent a CNS mechanism that underlies the oft-described phenomena of the "sweet tooth" and carbohydrate craving.
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Herwig A, Campbell G, Mayer CD, Boelen A, Anderson RA, Ross AW, Mercer JG, Barrett P. A thyroid hormone challenge in hypothyroid rats identifies T3 regulated genes in the hypothalamus and in models with altered energy balance and glucose homeostasis. Thyroid 2014; 24:1575-93. [PMID: 25087834 PMCID: PMC4229697 DOI: 10.1089/thy.2014.0169] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND The thyroid hormone triiodothyronine (T3) is known to affect energy balance. Recent evidence points to an action of T3 in the hypothalamus, a key area of the brain involved in energy homeostasis, but the components and mechanisms are far from understood. The aim of this study was to identify components in the hypothalamus that may be involved in the action of T3 on energy balance regulatory mechanisms. METHODS Sprague Dawley rats were made hypothyroid by giving 0.025% methimazole (MMI) in their drinking water for 22 days. On day 21, half the MMI-treated rats received a saline injection, whereas the others were injected with T3. Food intake and body weight measurements were taken daily. Body composition was determined by magnetic resonance imaging, gene expression was analyzed by in situ hybridization, and T3-induced gene expression was determined by microarray analysis of MMI-treated compared to MMI-T3-injected hypothalamic RNA. RESULTS Post mortem serum thyroid hormone levels showed that MMI treatment decreased circulating thyroid hormones and increased thyrotropin (TSH). MMI treatment decreased food intake and body weight. Body composition analysis revealed reduced lean and fat mass in thyroidectomized rats from day 14 of the experiment. MMI treatment caused a decrease in circulating triglyceride concentrations, an increase in nonesterified fatty acids, and decreased insulin levels. A glucose tolerance test showed impaired glucose clearance in the thyroidectomized animals. In the brain, in situ hybridization revealed marked changes in gene expression, including genes such as Mct8, a thyroid hormone transporter, and Agrp, a key component in energy balance regulation. Microarray analysis revealed 110 genes to be up- or downregulated with T3 treatment (± 1.3-fold change, p<0.05). Three genes chosen from the differentially expressed genes were verified by in situ hybridization to be activated by T3 in cells located at or close to the hypothalamic ventricular ependymal layer and differentially expressed in animal models of long- and short-term body weight regulation. CONCLUSION This study identified genes regulated by T3 in the hypothalamus, a key area of the brain involved in homeostasis and neuroendocrine functions. These include genes hitherto not known to be regulated by thyroid status.
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Affiliation(s)
- Annika Herwig
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
- Zoological Institute, University of Hamburg, Hamburg, Germany
| | - Gill Campbell
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Claus-Dieter Mayer
- Biomathematics and Statistics Scotland, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Anita Boelen
- Department of Endocrinology, Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Richard A. Anderson
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Alexander W. Ross
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Julian G. Mercer
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Perry Barrett
- Ingestive Behaviour Group, Rowett Institute for Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
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Santini F, Marzullo P, Rotondi M, Ceccarini G, Pagano L, Ippolito S, Chiovato L, Biondi B. Mechanisms in endocrinology: the crosstalk between thyroid gland and adipose tissue: signal integration in health and disease. Eur J Endocrinol 2014; 171:R137-52. [PMID: 25214234 DOI: 10.1530/eje-14-0067] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Obesity and thyroid diseases are common disorders in the general population and they frequently occur in single individuals. Alongside a chance association, a direct relationship between 'thyroid and obesity' has been hypothesized. Thyroid hormone is an important determinant of energy expenditure and contributes to appetite regulation, while hormones and cytokines from the adipose tissue act on the CNS to inform on the quantity of energy stores. A continuous interaction between the thyroid hormone and regulatory mechanisms localized in adipose tissue and brain is important for human body weight control and maintenance of optimal energy balance. Whether obesity has a pathogenic role in thyroid disease remains largely a matter of investigation. This review highlights the complexity in the identification of thyroid hormone deficiency in obese patients. Regardless of the importance of treating subclinical and overt hypothyroidism, at present there is no evidence to recommend pharmacological correction of the isolated hyperthyrotropinemia often encountered in obese patients. While thyroid hormones are not indicated as anti-obesity drugs, preclinical studies suggest that thyromimetic drugs, by targeting selected receptors, might be useful in the treatment of obesity and dyslipidemia.
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Affiliation(s)
- Ferruccio Santini
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Paolo Marzullo
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Mario Rotondi
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Giovanni Ceccarini
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Loredana Pagano
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Serena Ippolito
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Luca Chiovato
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Bernadette Biondi
- Endocrinology UnitObesity Center, University Hospital of Pisa, Pisa, ItalyDepartment of Translational MedicineUniversity of Piemonte Orientale, Novara, ItalyDivision of General MedicineI.R.C.C.S. Istituto Auxologico Italiano, Verbania, ItalyUnit of Internal Medicine and EndocrinologyFondazione Salvatore Maugeri I.R.C.C.S., University of Pavia, Pavia, ItalyDepartment of Clinical Medicine and SurgeryUniversity of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
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The neuroanatomical function of leptin in the hypothalamus. J Chem Neuroanat 2014; 61-62:207-20. [PMID: 25007719 DOI: 10.1016/j.jchemneu.2014.05.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 05/09/2014] [Accepted: 05/28/2014] [Indexed: 02/07/2023]
Abstract
The anorexigenic hormone leptin plays an important role in the control of food intake and feeding-related behavior, for an important part through its action in the hypothalamus. The adipose-derived hormone modulates a complex network of several intercommunicating orexigenic and anorexigenic neuropeptides in the hypothalamus to reduce food intake and increase energy expenditure. In this review we present an updated overview of the functional role of leptin in respect to feeding and feeding-related behavior per distinct hypothalamic nuclei. In addition to the arcuate nucleus, which is a major leptin sensitive hub, leptin-responsive neurons in other hypothalamic nuclei, including the, dorsomedial-, ventromedial- and paraventricular nucleus and the lateral hypothalamic area, are direct targets of leptin. However, leptin also modulates hypothalamic neurons in an indirect manner, such as via the melanocortin system. The dissection of the complexity of leptin's action on the networks involved in energy balance is subject of recent and future studies. A full understanding of the role of hypothalamic leptin in the regulation of energy balance requires cell-specific manipulation using of conditional deletion and expression of leptin receptors. In addition, optogenetic and pharmacogenetic tools in combination with other pharmacological (such as the recent discovery of a leptin receptor antagonist) and neuronal tracing techniques to map the circuit, will be helpful to understand the role of leptin receptor expressing neurons. Better understanding of these circuits and the involvement of leptin could provide potential sites for therapeutic interventions in obesity and metabolic diseases characterized by dysregulation of energy balance.
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Fekete C, Lechan RM. Central regulation of hypothalamic-pituitary-thyroid axis under physiological and pathophysiological conditions. Endocr Rev 2014; 35:159-94. [PMID: 24423980 PMCID: PMC3963261 DOI: 10.1210/er.2013-1087] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 11/05/2013] [Indexed: 12/18/2022]
Abstract
TRH is a tripeptide amide that functions as a neurotransmitter but also serves as a neurohormone that has a critical role in the central regulation of the hypothalamic-pituitary-thyroid axis. Hypophysiotropic TRH neurons involved in this neuroendocrine process are located in the hypothalamic paraventricular nucleus and secrete TRH into the pericapillary space of the external zone of the median eminence for conveyance to anterior pituitary thyrotrophs. Under basal conditions, the activity of hypophysiotropic TRH neurons is regulated by the negative feedback effects of thyroid hormone to ensure stable, circulating, thyroid hormone concentrations, a mechanism that involves complex interactions between hypophysiotropic TRH neurons and the vascular system, cerebrospinal fluid, and specialized glial cells called tanycytes. Hypophysiotropic TRH neurons also integrate other humoral and neuronal inputs that can alter the setpoint for negative feedback regulation by thyroid hormone. This mechanism facilitates adaptation of the organism to changing environmental conditions, including the shortage of food and a cold environment. The thyroid axis is also affected by other adverse conditions such as infection, but the central mechanisms mediating suppression of hypophysiotropic TRH may be pathophysiological. In this review, we discuss current knowledge about the mechanisms that contribute to the regulation of hypophysiotropic TRH neurons under physiological and pathophysiological conditions.
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Affiliation(s)
- Csaba Fekete
- Department of Endocrine Neurobiology (C.F.), Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083 Budapest, Hungary; Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism (C.F., R.M.L.), Tupper Research Institute, Tufts Medical Center, Boston, Massachusetts 02111; and Department of Neuroscience (R.M.L.), Tufts University School of Medicine, Boston, Massachusetts 02111
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Sasaki T, Kikuchi O, Shimpuku M, Susanti VY, Yokota-Hashimoto H, Taguchi R, Shibusawa N, Sato T, Tang L, Amano K, Kitazumi T, Kuroko M, Fujita Y, Maruyama J, Lee YS, Kobayashi M, Nakagawa T, Minokoshi Y, Harada A, Yamada M, Kitamura T. Hypothalamic SIRT1 prevents age-associated weight gain by improving leptin sensitivity in mice. Diabetologia 2014; 57:819-31. [PMID: 24374551 PMCID: PMC3940852 DOI: 10.1007/s00125-013-3140-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 11/25/2013] [Indexed: 01/10/2023]
Abstract
AIMS/HYPOTHESIS Obesity is associated with ageing and increased energy intake, while restriction of energy intake improves health and longevity in multiple organisms; the NAD(+)-dependent deacetylase sirtuin 1 (SIRT1) is implicated in this process. Pro-opiomelanocortin (POMC) and agouti-related peptide (AgRP) neurons in the arcuate nucleus (ARC) of the hypothalamus are critical for energy balance regulation, and the level of SIRT1 protein decreases with age in the ARC. In the current study we tested whether conditional Sirt1 overexpression in mouse POMC or AgRP neurons prevents age-associated weight gain and diet-induced obesity. METHODS We targeted Sirt1 cDNA sequence into the Rosa26 locus and generated conditional Sirt1 knock-in mice. These mice were crossed with mice harbouring either Pomc-Cre or Agrp-Cre and the metabolic variables, food intake, energy expenditure and sympathetic activity in adipose tissue of the resultant mice were analysed. We also used a hypothalamic cell line to investigate the molecular mechanism by which Sirt1 overexpression modulates leptin signalling. RESULTS Conditional Sirt1 overexpression in mouse POMC or AgRP neurons prevented age-associated weight gain; overexpression in POMC neurons stimulated energy expenditure via increased sympathetic activity in adipose tissue, whereas overexpression in AgRP neurons suppressed food intake. SIRT1 improved leptin sensitivity in hypothalamic neurons in vitro and in vivo by downregulating protein-tyrosine phosphatase 1B, T cell protein-tyrosine phosphatase and suppressor of cytokine signalling 3. However, these phenotypes were absent in mice consuming a high-fat, high-sucrose diet due to decreases in ARC SIRT1 protein and hypothalamic NAD(+) levels. CONCLUSIONS/INTERPRETATION ARC SIRT1 is a negative regulator of energy balance, and decline in ARC SIRT1 function contributes to disruption of energy homeostasis by ageing and diet-induced obesity.
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Affiliation(s)
- Tsutomu Sasaki
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Osamu Kikuchi
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Mayumi Shimpuku
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Vina Yanti Susanti
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Hiromi Yokota-Hashimoto
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Ryo Taguchi
- Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma Japan
| | - Nobuyuki Shibusawa
- Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma Japan
| | - Takashi Sato
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma Japan
| | - Lijun Tang
- Division of Endocrinology and Metabolism, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Aichi Japan
| | - Kosuke Amano
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Tomoya Kitazumi
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Mitsutaka Kuroko
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Yuki Fujita
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Jun Maruyama
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Yong-soo Lee
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Masaki Kobayashi
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
| | - Takashi Nakagawa
- Frontier Research Core for Life Science, University of Toyama, Toyama, Toyama Japan
| | - Yasuhiko Minokoshi
- Division of Endocrinology and Metabolism, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Aichi Japan
| | - Akihiro Harada
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma Japan
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Osaka Japan
| | - Masanobu Yamada
- Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma Japan
| | - Tadahiro Kitamura
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi-shi, Gunma 371-8512 Japan
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Ramos CF, Zamoner A. Thyroid hormone and leptin in the testis. Front Endocrinol (Lausanne) 2014; 5:198. [PMID: 25505448 PMCID: PMC4243692 DOI: 10.3389/fendo.2014.00198] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 11/10/2014] [Indexed: 12/18/2022] Open
Abstract
Leptin is primarily expressed in white adipose tissue; however, it is expressed in the hypothalamus and reproductive tissues as well. Leptin acts by activating the leptin receptors (Ob-Rs). Additionally, the regulation of several neuroendocrine and reproductive functions, including the inhibition of glucocorticoids and enhancement of thyroxine and sex hormone concentrations in human beings and mice are leptin functions. It has been suggested that thyroid hormones (TH) could directly regulate leptin expression. Additionally, hypothyroidism compromises the intracellular integration of leptin signaling specifically in the arcuate nucleus. Two TH receptor isoforms are expressed in the testis, TRa and TRb, with TRa being the predominant one that is present in all stages of development. The effects of TH involve the proliferation and differentiation of Sertoli and Leydig cells during development, spermatogenesis, and steroidogenesis. In this context, TH disorders are associated with sexual dysfunction. An endocrine and/or direct paracrine effect of leptin on the gonads inhibits testosterone production in Leydig cells. Further studies are necessary to clarify the effects of both hormones in the testis during hypothyroidism. The goal of this review is to highlight the current knowledge regarding leptin and TH in the testis.
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Affiliation(s)
- Cristiane Fonte Ramos
- Laboratory of Morphometry, Metabolism and Cardiovascular Disease, Department of Anatomy, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Cristiane Fonte Ramos, Laboratório de Morfometria, Metabolismo e Doença Cardiovascular, Centro Biomédico, Instituto de Biologia, Universidade do Estado do Rio de Janeiro. Av 28 de Setembro 87 fds, Rio de Janeiro 20551-030, RJ, Brazil e-mail:
| | - Ariane Zamoner
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
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Girardet C, Butler AA. Neural melanocortin receptors in obesity and related metabolic disorders. Biochim Biophys Acta Mol Basis Dis 2013; 1842:482-94. [PMID: 23680515 DOI: 10.1016/j.bbadis.2013.05.004] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/16/2013] [Accepted: 05/03/2013] [Indexed: 12/11/2022]
Abstract
Obesity is a global health issue, as it is associated with increased risk of developing chronic conditions associated with disorders of metabolism such as type 2 diabetes and cardiovascular disease. A better understanding of how excessive fat accumulation develops and causes diseases of the metabolic syndrome is urgently needed. The hypothalamic melanocortin system is an important point of convergence connecting signals of metabolic status with the neural circuitry that governs appetite and the autonomic and neuroendocrine system controling metabolism. This system has a critical role in the defense of body weight and maintenance of homeostasis. Two neural melanocortin receptors, melanocortin 3 and 4 receptors (MC3R and MC4R), play crucial roles in the regulation of energy balance. Mutations in the MC4R gene are the most common cause of monogenic obesity in humans, and a large literature indicates a role in regulating both energy intake through the control of satiety and energy expenditure. In contrast, MC3Rs have a more subtle role in energy homeostasis. Results from our lab indicate an important role for MC3Rs in synchronizing rhythms in foraging behavior with caloric cues and maintaining metabolic homeostasis during periods of nutrient scarcity. However, while deletion of the Mc3r gene in mice alters nutrient partitioning to favor accumulation of fat mass no obvious role for MC3R haploinsufficiency in human obesity has been reported. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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MESH Headings
- Animals
- Body Weight/genetics
- Cardiovascular Diseases/complications
- Cardiovascular Diseases/metabolism
- Cardiovascular Diseases/pathology
- Diabetes Mellitus, Type 2/complications
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Humans
- Metabolic Diseases/genetics
- Metabolic Diseases/metabolism
- Metabolic Diseases/pathology
- Mice
- Obesity/complications
- Obesity/genetics
- Obesity/metabolism
- Obesity/pathology
- Receptor, Melanocortin, Type 3/genetics
- Receptor, Melanocortin, Type 3/metabolism
- Receptor, Melanocortin, Type 4/genetics
- Receptor, Melanocortin, Type 4/metabolism
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Affiliation(s)
- Clemence Girardet
- Department of Metabolism and Aging, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Andrew A Butler
- Department of Metabolism and Aging, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA.
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Camps SGJA, Verhoef SPM, Westerterp KR. Weight loss, weight maintenance, and adaptive thermogenesis. Am J Clin Nutr 2013; 97:990-4. [PMID: 23535105 DOI: 10.3945/ajcn.112.050310] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Diet-induced weight loss is accompanied by adaptive thermogenesis, ie, a disproportional or greater than expected reduction of resting metabolic rate (RMR). OBJECTIVE The aim of this study was to investigate whether adaptive thermogenesis is sustained during weight maintenance after weight loss. DESIGN Subjects were 22 men and 69 women [mean ± SD age: 40 ± 9 y; body mass index (BMI; in kg/m(2)): 31.9 ± 3.0]. They followed a very-low-energy diet for 8 wk, followed by a 44-wk period of weight maintenance. Body composition was assessed with a 3-compartment model based on body weight, total body water (deuterium dilution), and body volume. RMR was measured (RMRm) with a ventilated hood. In addition, RMR was predicted (RMRp) on the basis of the measured body composition: RMRp (MJ/d) = 0.024 × fat mass (kg) + 0.102 × fat-free mass (kg) + 0.85. Measurements took place before the diet and 8, 20, and 52 wk after the start of the diet. RESULTS The ratio of RMRm to RMRp decreased from 1.004 ± 0.077 before the diet to 0.963 ± 0.073 after the diet (P < 0.001), and the decrease was sustained after 20 wk (0.983 ± 0.063; P < 0.01) and 52 wk (0.984 ± 0.068; P < 0.01). RMRm/RMRp was correlated with the weight loss after 8 wk (P < 0.01), 20 wk (P < 0.05), and 52 wk (P < 0.05). CONCLUSION Weight loss results in adaptive thermogenesis, and there is no indication for a change in adaptive thermogenesis up to 1 y, when weight loss is maintained. This trial was registered at clinicaltrials.gov as NCT01015508.
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Affiliation(s)
- Stefan G J A Camps
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, Netherlands.
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Abstract
Leptin is secreted into the bloodstream by adipocytes and is required for the maintenance of energy homeostasis and body weight. Leptin deficiency or genetic defects in the components of the leptin signaling pathways cause obesity. Leptin controls energy balance and body weight mainly through leptin receptor b (LEPRb)-expressing neurons in the brain, particularly in the hypothalamus. These LEPRb-expressing neurons function as the first-order neurons that project to the second-order neurons located within and outside the hypothalamus, forming a neural network that controls the energy homeostasis and body weight. Multiple factors, including inflammation and endoplasmic reticulum (ER) stress, contribute to leptin resistance. Leptin resistance is the key risk factor for obesity. This review is focused on recent advance about leptin action, leptin signaling, and leptin resistance.
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