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Wang J, O'Reilly M, Cooper IA, Chehrehasa F, Moody H, Beecher K. Mapping GABAergic projections that mediate feeding. Neurosci Biobehav Rev 2024; 163:105743. [PMID: 38821151 DOI: 10.1016/j.neubiorev.2024.105743] [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: 03/25/2024] [Revised: 05/23/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Neuroscience offers important insights into the pathogenesis and treatment of obesity by investigating neural circuits underpinning appetite and feeding. Gamma-aminobutyric acid (GABA), one of the most abundant neurotransmitters in the brain, and its associated receptors represent an array of pharmacologically targetable mediators of appetite signalling. Targeting the GABAergic system is therefore an increasingly investigated approach to obesity treatment. However, the many GABAergic projections that control feeding have yet to be collectively analysed. This review provides a comprehensive analysis of the relationship between GABAergic signalling and appetite by examining both foundational studies and the results of newly emerging chemogenetic/optogenetic experiments. A current snapshot of these efforts to map GABAergic projections influencing appetite is provided, and potential avenues for further investigation are provided.
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Affiliation(s)
- Joshua Wang
- School of Clinical Sciences, Faculty of Health, Queensland University of Technology, 2 George Street, Brisbane 4000, QLD, Australia.
| | - Max O'Reilly
- UQ Centre for Clinical Research, Faculty of Medicine, University of Queensland, Building 71/918 Royal Brisbane and Women's Hospital Campus, Herston 4029, QLD, Australia
| | | | - Fatemeh Chehrehasa
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, 2 George Street, Brisbane 4000, QLD, Australia
| | - Hayley Moody
- Queensland University of Technology, 2 George Street, Brisbane 4000, QLD, Australia
| | - Kate Beecher
- UQ Centre for Clinical Research, Faculty of Medicine, University of Queensland, Building 71/918 Royal Brisbane and Women's Hospital Campus, Herston 4029, QLD, Australia
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2
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Le Thuc O, García-Cáceres C. Obesity-induced inflammation: connecting the periphery to the brain. Nat Metab 2024:10.1038/s42255-024-01079-8. [PMID: 38997442 DOI: 10.1038/s42255-024-01079-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 06/11/2024] [Indexed: 07/14/2024]
Abstract
Obesity is often associated with a chronic, low-grade inflammatory state affecting the entire body. This sustained inflammatory state disrupts the coordinated communication between the periphery and the brain, which has a crucial role in maintaining homeostasis through humoural, nutrient-mediated, immune and nervous signalling pathways. The inflammatory changes induced by obesity specifically affect communication interfaces, including the blood-brain barrier, glymphatic system and meninges. Consequently, brain areas near the third ventricle, including the hypothalamus and other cognition-relevant regions, become susceptible to impairments, resulting in energy homeostasis dysregulation and an elevated risk of cognitive impairments such as Alzheimer's disease and dementia. This Review explores the intricate communication between the brain and the periphery, highlighting the effect of obesity-induced inflammation on brain function.
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Affiliation(s)
- Ophélia Le Thuc
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Cristina García-Cáceres
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, Neuherberg, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany.
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3
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Bachor TP, Hwang E, Yulyaningsih E, Attal K, Mifsud F, Pham V, Vagena E, Huarcaya R, Valdearcos M, Vaisse C, Williams KW, Emmerson PJ, Xu AW. Identification of AgRP cells in the murine hindbrain that drive feeding. Mol Metab 2024; 80:101886. [PMID: 38246589 PMCID: PMC10844855 DOI: 10.1016/j.molmet.2024.101886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/10/2024] [Accepted: 01/16/2024] [Indexed: 01/23/2024] Open
Abstract
OBJECTIVE The central melanocortin system is essential for the regulation of food intake and body weight. Agouti-related protein (AgRP) is the sole orexigenic component of the central melanocortin system and is conserved across mammalian species. AgRP is currently known to be expressed exclusively in the mediobasal hypothalamus, and hypothalamic AgRP-expressing neurons are essential for feeding. Here we characterized a previously unknown population of AgRP cells in the mouse hindbrain. METHODS Expression of AgRP in the hindbrain was investigated using gene expression analysis, single-cell RNA sequencing, immunofluorescent analysis and multiple transgenic mice with reporter expressions. Activation of AgRP neurons was achieved by Designer Receptors Exclusively Activated by Designer Drugs (DREADD) and by transcranial focal photo-stimulation using a step-function opsin with ultra-high light sensitivity (SOUL). RESULTS AgRP expressing cells were present in the area postrema (AP) and the adjacent subpostrema area (SubP) and commissural nucleus of the solitary tract (cNTS) of the mouse hindbrain (termed AgRPHind herein). AgRPHind cells consisted of locally projecting neurons as well as tanycyte-like cells. Food deprivation stimulated hindbrain Agrp expression as well as neuronal activity of subsets of AgRPHind cells. In adult mice that lacked hypothalamic AgRP neurons, chemogenetic activation of AgRP neurons resulted in hyperphagia and weight gain. In addition, transcranial focal photo-stimulation of hindbrain AgRP cells increased food intake in adult mice with or without hypothalamic AgRP neurons. CONCLUSIONS Our study indicates that the central melanocortin system in the hindbrain possesses an orexigenic component, and that AgRPHind neurons stimulate feeding independently of hypothalamic AgRP neurons.
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Affiliation(s)
- Tomas P Bachor
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Eunsang Hwang
- Center for Hypothalamic Research, Department of Internal Medicine, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Ernie Yulyaningsih
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Kush Attal
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Francois Mifsud
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Viana Pham
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Eirini Vagena
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Renzo Huarcaya
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Martin Valdearcos
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Christian Vaisse
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA
| | - Kevin W Williams
- Center for Hypothalamic Research, Department of Internal Medicine, the University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Paul J Emmerson
- Lilly Research Laboratories, Lilly Corporate Center, Eli Lilly & Company, Indianapolis, IN, USA
| | - Allison W Xu
- Diabetes Center and Department of Anatomy, University of California, San Francisco, California, USA.
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4
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Huang A, Maier MT, Vagena E, Xu AW. Modulation of foraging-like behaviors by cholesterol-FGF19 axis. Cell Biosci 2023; 13:20. [PMID: 36732847 PMCID: PMC9893607 DOI: 10.1186/s13578-023-00955-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/03/2023] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Foraging for food precedes food consumption and is an important component of the overall metabolic programming that regulates feeding. Foraging is governed by central nervous system neuronal circuits but how it is influenced by diet and hormonal signals is still not well understood. RESULTS In this study, we show that dietary cholesterol exerted suppressive effects on locomotor activity and that these effects were partially mediated by the neuropeptide Agouti-related protein (AgRP). High dietary cholesterol stimulated intestinal expression of fibroblast growth factor 15 (Fgf15), an ortholog of the human fibroblast growth factor 19 (FGF19). Intracerebroventricular infusion of FGF19 peptide reduced exploratory activity in the open field test paradigm. On the other hand, the lack of dietary cholesterol enhanced exploratory activity in the open field test, but this effect was abolished by central administration of FGF19. CONCLUSIONS Experiments in this study show that dietary cholesterol suppresses locomotor activity and foraging-like behaviors, and this regulation is in part mediated by AgRP neurons. Dietary cholesterol or the central action of FGF19 suppresses exploratory behaviors, and the anxiogenic effects of dietary cholesterol may be mediated by the effect of FGF19 in the mouse brain. This study suggests that dietary cholesterol and intestinal hormone FGF15/19 signal a satiating state to the brain, thereby suppressing foraging-like behaviors.
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Affiliation(s)
- Alyssa Huang
- Diabetes Center, University of California, San Francisco, CA, 94143, USA
| | - Matthew T Maier
- Diabetes Center, University of California, San Francisco, CA, 94143, USA
| | - Eirini Vagena
- Diabetes Center, University of California, San Francisco, CA, 94143, USA
| | - Allison W Xu
- Diabetes Center, University of California, San Francisco, CA, 94143, USA. .,Department of Anatomy, University of California, San Francisco, CA, 94143, USA.
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Inada K, Tsujimoto K, Yoshida M, Nishimori K, Miyamichi K. Oxytocin signaling in the posterior hypothalamus prevents hyperphagic obesity in mice. eLife 2022; 11:75718. [PMID: 36281647 PMCID: PMC9596155 DOI: 10.7554/elife.75718] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 10/12/2022] [Indexed: 11/17/2022] Open
Abstract
Decades of studies have revealed molecular and neural circuit bases for body weight homeostasis. Neural hormone oxytocin (Oxt) has received attention in this context because it is produced by neurons in the paraventricular hypothalamic nucleus (PVH), a known output center of hypothalamic regulation of appetite. Oxt has an anorexigenic effect, as shown in human studies, and can mediate satiety signals in rodents. However, the function of Oxt signaling in the physiological regulation of appetite has remained in question, because whole-body knockout (KO) of Oxt or Oxt receptor (Oxtr) has little effect on food intake. We herein show that acute conditional KO (cKO) of Oxt selectively in the adult PVH, but not in the supraoptic nucleus, markedly increases body weight and food intake, with an elevated level of plasma triglyceride and leptin. Intraperitoneal administration of Oxt rescues the hyperphagic phenotype of the PVH Oxt cKO model. Furthermore, we show that cKO of Oxtr selectively in the posterior hypothalamic regions, especially the arcuate hypothalamic nucleus, a primary center for appetite regulations, phenocopies hyperphagic obesity. Collectively, these data reveal that Oxt signaling in the arcuate nucleus suppresses excessive food intake.
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Affiliation(s)
- Kengo Inada
- RIKEN Center for Biosystems Dynamics Research
| | | | - Masahide Yoshida
- Laboratory of Molecular Biology, Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University
| | - Katsuhiko Nishimori
- Laboratory of Molecular Biology, Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University
- Department of Obesity and Inflammation Research, Fukushima Medical University
| | - Kazunari Miyamichi
- RIKEN Center for Biosystems Dynamics Research
- CREST, Japan Science and Technology Agency
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6
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Miyata S. Glial functions in the blood-brain communication at the circumventricular organs. Front Neurosci 2022; 16:991779. [PMID: 36278020 PMCID: PMC9583022 DOI: 10.3389/fnins.2022.991779] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The circumventricular organs (CVOs) are located around the brain ventricles, lack a blood-brain barrier (BBB) and sense blood-derived molecules. This review discusses recent advances in the importance of CVO functions, especially glial cells transferring periphery inflammation signals to the brain. The CVOs show size-limited vascular permeability, allowing the passage of molecules with molecular weight <10,000. This indicates that the lack of an endothelial cell barrier does not mean the free movement of blood-derived molecules into the CVO parenchyma. Astrocytes and tanycytes constitute a dense barrier at the distal CVO subdivision, preventing the free diffusion of blood-derived molecules into neighboring brain regions. Tanycytes in the CVOs mediate communication between cerebrospinal fluid and brain parenchyma via transcytosis. Microglia and macrophages of the CVOs are essential for transmitting peripheral information to other brain regions via toll-like receptor 2 (TLR2). Inhibition of TLR2 signaling or depletion of microglia and macrophages in the brain eliminates TLR2-dependent inflammatory responses. In contrast to TLR2, astrocytes and tanycytes in the CVOs of the brain are crucial for initiating lipopolysaccharide (LPS)-induced inflammatory responses via TLR4. Depletion of microglia and macrophages augments LPS-induced fever and chronic sickness responses. Microglia and macrophages in the CVOs are continuously activated, even under normal physiological conditions, as they exhibit activated morphology and express the M1/M2 marker proteins. Moreover, the microglial proliferation occurs in various regions, such as the hypothalamus, medulla oblongata, and telencephalon, with a marked increase in the CVOs, due to low-dose LPS administration, and after high-dose LPS administration, proliferation is seen in most brain regions, except for the cerebral cortex and hippocampus. A transient increase in the microglial population is beneficial during LPS-induced inflammation for attenuating sickness response. Transient receptor potential receptor vanilloid 1 expressed in astrocytes and tanycytes of the CVOs is responsible for thermoregulation upon exposure to a warm environment less than 37°C. Alternatively, Nax expressed in astrocytes and tanycytes of the CVOs is crucial for maintaining body fluid homeostasis. Thus, recent findings indicate that glial cells in the brain CVOs are essential for initiating neuroinflammatory responses and maintaining body fluid and thermal homeostasis.
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Tanycytes control hypothalamic liraglutide uptake and its anti-obesity actions. Cell Metab 2022; 34:1054-1063.e7. [PMID: 35716660 PMCID: PMC7613793 DOI: 10.1016/j.cmet.2022.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 08/08/2021] [Accepted: 06/01/2022] [Indexed: 11/24/2022]
Abstract
Liraglutide, an anti-diabetic drug and agonist of the glucagon-like peptide one receptor (GLP1R), has recently been approved to treat obesity in individuals with or without type 2 diabetes. Despite its extensive metabolic benefits, the mechanism and site of action of liraglutide remain unclear. Here, we demonstrate that liraglutide is shuttled to target cells in the mouse hypothalamus by specialized ependymoglial cells called tanycytes, bypassing the blood-brain barrier. Selectively silencing GLP1R in tanycytes or inhibiting tanycytic transcytosis by botulinum neurotoxin expression not only hampers liraglutide transport into the brain and its activation of target hypothalamic neurons, but also blocks its anti-obesity effects on food intake, body weight and fat mass, and fatty acid oxidation. Collectively, these striking data indicate that the liraglutide-induced activation of hypothalamic neurons and its downstream metabolic effects are mediated by its tanycytic transport into the mediobasal hypothalamus, strengthening the notion of tanycytes as key regulators of metabolic homeostasis.
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8
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Nampoothiri S, Nogueiras R, Schwaninger M, Prevot V. Glial cells as integrators of peripheral and central signals in the regulation of energy homeostasis. Nat Metab 2022; 4:813-825. [PMID: 35879459 PMCID: PMC7613794 DOI: 10.1038/s42255-022-00610-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 06/15/2022] [Indexed: 01/03/2023]
Abstract
Communication between the periphery and the brain is key for maintaining energy homeostasis. To do so, peripheral signals from the circulation reach the brain via the circumventricular organs (CVOs), which are characterized by fenestrated vessels lacking the protective blood-brain barrier (BBB). Glial cells, by virtue of their plasticity and their ideal location at the interface of blood vessels and neurons, participate in the integration and transmission of peripheral information to neuronal networks in the brain for the neuroendocrine control of whole-body metabolism. Metabolic diseases, such as obesity and type 2 diabetes, can disrupt the brain-to-periphery communication mediated by glial cells, highlighting the relevance of these cell types in the pathophysiology of such complications. An improved understanding of how glial cells integrate and respond to metabolic and humoral signals has become a priority for the discovery of promising therapeutic strategies to treat metabolic disorders. This Review highlights the role of glial cells in the exchange of metabolic signals between the periphery and the brain that are relevant for the regulation of whole-body energy homeostasis.
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Affiliation(s)
- Sreekala Nampoothiri
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Ruben Nogueiras
- Universidade de Santiago de Compostela-Instituto de Investigation Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatologia de la Obesidad y Nutrition, Santiago de Compostela, Spain
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Vincent Prevot
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France.
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9
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Vagena E, Crneta J, Engström P, He L, Yulyaningsih E, Korpel NL, Cheang RT, Bachor TP, Huang A, Michel G, Attal K, Berrios DI, Valdearcos M, Koliwad SK, Olson DP, Yi CX, Xu AW. ASB4 modulates central melanocortinergic neurons and calcitonin signaling to control satiety and glucose homeostasis. Sci Signal 2022; 15:eabj8204. [PMID: 35536884 DOI: 10.1126/scisignal.abj8204] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Variants in the gene encoding ankyrin repeat and SOCS box-containing 4 (ASB4) are linked to human obesity. Here, we characterized the pathways underlying the metabolic functions of ASB4. Hypothalamic Asb4 expression was suppressed by fasting in wild-type mice but not in mice deficient in AgRP, which encodes Agouti-related protein (AgRP), an appetite-stimulating hormone, suggesting that ASB4 is a negative target of AgRP. Many ASB4 neurons in the brain were adjacent to AgRP terminals, and feeding induced by AgRP neuronal activation was disrupted in Asb4-deficient mice. Acute knockdown of Asb4 in the brain caused marked hyperphagia due to increased meal size, and Asb4 deficiency led to increased meal size and food intake at the onset of refeeding, when very large meals were consumed. Asb4-deficient mice were resistant to the meal-terminating effects of exogenously administered calcitonin and showed decreased neuronal expression of Calcr, which encodes the calcitonin receptor. Pro-opiomelanocortin (POMC) neurons in the arcuate nucleus in mice are involved in glucose homeostasis, and Asb4 deficiency specifically in POMC neurons resulted in glucose intolerance that was independent of obesity. Furthermore, individuals with type 2 diabetes showed reduced ASB4 abundance in the infundibular nuclei, the human equivalent of the arcuate nucleus. Together, our results indicate that ASB4 acts in the brain to improve glucose homeostasis and to induce satiety after substantial meals, particularly those after food deprivation.
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Affiliation(s)
- Eirini Vagena
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jasmina Crneta
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Pauline Engström
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Li He
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Ernie Yulyaningsih
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Nikita L Korpel
- Department of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, Amsterdam 1105 AZ, Netherlands
| | - Rachel T Cheang
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Tomas P Bachor
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Alyssa Huang
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Guillermina Michel
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kush Attal
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - David I Berrios
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Martin Valdearcos
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Suneil K Koliwad
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - David P Olson
- Department of Pediatrics, Michigan Medicine, Ann Arbor, MI 48109, USA
| | - Chun-Xia Yi
- Department of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, Amsterdam 1105 AZ, Netherlands
| | - Allison W Xu
- Diabetes Center, University of California, San Francisco, San Francisco, CA 94143, USA.,Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
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10
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Fernandez G, Cabral A, De Francesco PN, Uriarte M, Reynaldo M, Castrogiovanni D, Zubiría G, Giovambattista A, Cantel S, Denoyelle S, Fehrentz JA, Tolle V, Schiöth HB, Perello M. GHSR controls food deprivation-induced activation of CRF neurons of the hypothalamic paraventricular nucleus in a LEAP2-dependent manner. Cell Mol Life Sci 2022; 79:277. [PMID: 35504998 PMCID: PMC11072678 DOI: 10.1007/s00018-022-04302-5] [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] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/08/2022] [Accepted: 04/10/2022] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Prolonged fasting is a major challenge for living organisms. An appropriate metabolic response to food deprivation requires the activation of the corticotropin-releasing factor-producing neurons of the hypothalamic paraventricular nucleus (PVHCRF neurons), which are a part of the hypothalamic-pituitary-adrenal axis (HPA), as well as the growth hormone secretagogue receptor (GHSR) signaling, whose activity is up- or down-regulated, respectively, by the hormones ghrelin and the liver-expressed antimicrobial peptide 2 (LEAP2). Since ghrelin treatment potently up-regulates the HPA axis, we studied the role of GHSR in mediating food deprivation-induced activation of the PVHCRF neurons in mice. METHODS We estimated the activation of the PVHCRF neurons, using immuno-staining against CRF and the marker of neuronal activation c-Fos in brain sections, and assessed plasma levels of corticosterone and glucose in different pharmacologically or genetically manipulated mouse models exposed, or not, to a 2-day food deprivation protocol. In particular, we investigated ad libitum fed or food-deprived male mice that: (1) lacked GHSR gene expression, (2) had genetic deletion of the ghrelin gene, (3) displayed neurotoxic ablation of the hypothalamic arcuate nucleus, (4) were centrally treated with an anti-ghrelin antibody to block central ghrelin action, (5) were centrally treated with a GHSR ligand that blocks ghrelin-evoked and constitutive GHSR activities, or (6) received a continuous systemic infusion of LEAP2(1-12). RESULTS We found that food deprivation results in the activation of the PVHCRF neurons and in a rise of the ghrelin/LEAP2 molar ratio. Food deprivation-induced activation of PVHCRF neurons required the presence and the signaling of GHSR at hypothalamic level, but not of ghrelin. Finally, we found that preventing the food deprivation-induced fall of LEAP2 reverses the activation of the PVHCRF neurons in food-deprived mice, although it has no effect on body weight or blood glucose. CONCLUSION Food deprivation-induced activation of the PVHCRF neurons involves ghrelin-independent actions of GHSR at hypothalamic level and requires a decrease of plasma LEAP2 levels. We propose that the up-regulation of the actions of GHSR associated to the fall of plasma LEAP2 level are physiologically relevant neuroendocrine signals during a prolonged fasting.
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Affiliation(s)
- Gimena Fernandez
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Agustina Cabral
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Pablo N De Francesco
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Maia Uriarte
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Mirta Reynaldo
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Daniel Castrogiovanni
- Cell Culture Facility, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Guillermina Zubiría
- Laboratory of Neuroendocrinology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Andrés Giovambattista
- Laboratory of Neuroendocrinology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina
| | - Sonia Cantel
- Institut Des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM, Montpellier, France
| | - Severine Denoyelle
- Institut Des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM, Montpellier, France
| | - Jean-Alain Fehrentz
- Institut Des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM, Montpellier, France
| | - Virginie Tolle
- Institute of Psychiatry and Neuroscience of Paris, Université de Paris, UMR-S 1266 INSERM, Paris, France
| | - Helgi B Schiöth
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
- Institute for Translational Medicine and Biotechnology, I. M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Mario Perello
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata (UNLP)], Calle 526 S/N entre 10 y 11, La Plata, Buenos Aires, 1900, Argentina.
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden.
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11
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MyD88 Deficiency, but Not Gut Microbiota Depletion, Is Sufficient to Modulate the Blood-Brain Barrier Function in the Mediobasal Hypothalamus. Mol Neurobiol 2022; 59:3755-3766. [PMID: 35381888 PMCID: PMC9148286 DOI: 10.1007/s12035-022-02802-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 03/16/2022] [Indexed: 11/03/2022]
Abstract
Circumventricular organs (CVOs), including the mediobasal hypothalamus (MBH), have an incomplete blood–brain barrier (BBB). In this study, we determined if the BBB function in the MBH is modulated by the gut microbiota or by the Toll-like receptor (TLR) adapter proteins TRIF or MyD88 signaling. By injecting mice with Evans blue, a marker for BBB permeability, we show that germ-free (GF) and conventionally raised (CONV-R) mice did not differ in the number of Evans blue-positive cells in MBH. Acute modulation of the gut microbiota did not change the number of Evans blue-positive cells. In contrast, CONV-R Myd88−/− and Trif−/− mice had a reduced number of cells in direct contact to the circulation compared to wildtype (WT) mice. This was accompanied by increased tight junction proteins in the blood vessels in Myd88−/− mice. To further characterize the BBB function, we injected WT and Myd88 −/− CONV-R mice as well as WT GF mice with monosodium glutamate (MSG), a neurotoxin that does not cross the BBB. While MSG caused vast cell death in the MBH in CONV-R and GF WT mice, Myd88 −/− mice were protected from such cell death suggesting that fewer cells are exposed to the neurotoxin in the Myd88 −/− mice. Taken together, our results suggest that MyD88 deficiency, but not gut microbiota depletion, is sufficient to modulate the BBB function in the MBH.
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12
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Abstract
The role of central estrogen in cognitive, metabolic, and reproductive health has long fascinated the lay public and scientists alike. In the last two decades, insight into estrogen signaling in the brain and its impact on female physiology is beginning to catch up with the vast information already established for its actions on peripheral tissues. Using newer methods to manipulate estrogen signaling in hormone-sensitive brain regions, neuroscientists are now identifying the molecular pathways and neuronal subtypes required for controlling sex-dependent energy allocation. However, the immense cellular complexity of these hormone-sensitive brain regions makes it clear that more research is needed to fully appreciate how estrogen modulates neural circuits to regulate physiological and behavioral end points. Such insight is essential for understanding how natural or drug-induced hormone fluctuations across lifespan affect women's health.
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Affiliation(s)
- Holly A Ingraham
- Department of Cellular and Molecular Pharmacology, School of Medicine, Mission Bay, University of California, San Francisco, California, USA;
| | - Candice B Herber
- Department of Cellular and Molecular Pharmacology, School of Medicine, Mission Bay, University of California, San Francisco, California, USA;
| | - William C Krause
- Department of Cellular and Molecular Pharmacology, School of Medicine, Mission Bay, University of California, San Francisco, California, USA;
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13
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Maffei M, Giordano A. Leptin, the brain and energy homeostasis: From an apparently simple to a highly complex neuronal system. Rev Endocr Metab Disord 2022; 23:87-101. [PMID: 33822303 DOI: 10.1007/s11154-021-09636-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/11/2021] [Indexed: 12/14/2022]
Abstract
Leptin, produced and secreted by white adipose tissue in tight relationship with adipose mass, informs the brain about the status of the energy stores serving as the main peripheral signal for energy balance regulation through interaction with a multitude of highly interconnected neuronal populations. Most obese patients display resistance to the anorectic effect of the hormone. The present review unravels the multiple levels of complexity that trigger hypothalamic response to leptin with the objective of highlighting those critical hubs that, mainly in the hypothalamic arcuate nucleus, may undergo obesity-induced alterations and create an obstacle to leptin action. Several mechanisms underlying leptin resistance have been proposed, possibly representing useful targets to empower leptin effects. Among these, a special focus is herein dedicated to detail how leptin gains access into the brain and how neuronal plasticity may interfere with leptin function.
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Affiliation(s)
- Margherita Maffei
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124, Pisa, Italy.
- Obesity and Lipodystrophy Center, University Hospital of Pisa, Via Paradisa 2, 56124, Pisa, Italy.
| | - Antonio Giordano
- Department of Experimental and Clinical Medicine, Marche Polytechnic University, Via Tronto 10/A, 60020, Ancona, Italy.
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14
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Yu X, Li W. Comparative insights into the integration mechanism of neuropeptides to starvation and temperature stress. Gen Comp Endocrinol 2022; 316:113945. [PMID: 34826429 DOI: 10.1016/j.ygcen.2021.113945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/08/2021] [Accepted: 11/18/2021] [Indexed: 11/29/2022]
Abstract
Stress is known as the process of biological responses evoked by internal or external stimuli. The ability to sense, integrate and respond to stress signals is a requisite for life. Temperature and photoperiod are very important environmental factors for animals. In addition, stress signals can also be inputted from peripheral tissue, such as starvation and inflammation. Through afferent pathways, stress signals input to the central nervous system (CNS), where various signals will integrate, and the integrated information will transmit to the peripheral effectors. As the regulators of neural activity, neuropeptides play important roles in these processes. The present review summarizes recent findings about the integration mechanism of stress signals in the CNS, emphasizing on the role of neuropeptides.
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Affiliation(s)
- Xiaozheng Yu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Provincial Engineering Technology Research Center for Healthy Breeding of Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Wensheng Li
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Provincial Engineering Technology Research Center for Healthy Breeding of Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China.
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15
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de Paula DG, Bohlen TM, Zampieri TT, Mansano NS, Vieira HR, Gusmao DO, Wasinski F, Donato J, Frazao R. Distinct effects of growth hormone deficiency and disruption of hypothalamic kisspeptin system on reproduction of male mice. Life Sci 2021; 285:119970. [PMID: 34562435 DOI: 10.1016/j.lfs.2021.119970] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/08/2021] [Accepted: 09/16/2021] [Indexed: 12/30/2022]
Abstract
Growth hormone (GH) deficiency is a common cause of late sexual maturation and fertility issues. To determine whether GH-induced effects on reproduction are associated with alterations in hypothalamic kisspeptin system, we studied the male reproduction in two distinct GH deficiency mouse models. In the first model, mice present GH deficiency secondary to arcuate nucleus of the hypothalamus (ARH) lesions induced by posnatal monosodium glutamate (MSG) injections. MSG-induced ARH lesions led to significant reductions in hypothalamic Ghrh mRNA expression and consequently growth. Hypothalamic Kiss1 mRNA expression and Kiss1-expressing cells in the ARH were disrupted in the MSG-treated mice. In contrast, kisspeptin immunoreactivity remained preserved in the anteroventral periventricular and rostral periventricular nuclei (AVPV/PeN) of MSG-treated mice. Importantly, ARH lesions caused late sexual maturation and infertility in male mice. In our second mouse model, we studied animals profound GH deficiency due to a loss-of-function mutation in the Ghrhr gene (Ghrhrlit/lit mice). Interestingly, although Ghrhrlit/lit mice exhibited late puberty onset, hypothalamic Kiss1 mRNA expression and hypothalamic kisspeptin fiber density were normal in Ghrhrlit/lit mice. Despite presenting dwarfism, the majority of Ghrhrlit/lit male mice were fertile. These findings suggest that spontaneous GH deficiency during development does not compromise the kisspeptin system. Furthermore, ARH Kiss1-expressing neurons are required for fertility, while AVPV/PeN kisspeptin expression is sufficient to allow maturation of the hypothalamic-pituitary-gonadal axis in male mice.
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Affiliation(s)
- Daniella G de Paula
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Tabata M Bohlen
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Thais Tessari Zampieri
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Naira S Mansano
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Henrique R Vieira
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Daniela O Gusmao
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Frederick Wasinski
- 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
| | - Renata Frazao
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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16
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Surbhi, Wittmann G, Low MJ, Lechan RM. Adult-born proopiomelanocortin neurons derived from Rax-expressing precursors mitigate the metabolic effects of congenital hypothalamic proopiomelanocortin deficiency. Mol Metab 2021; 53:101312. [PMID: 34329773 PMCID: PMC8383116 DOI: 10.1016/j.molmet.2021.101312] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/12/2021] [Accepted: 07/25/2021] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE Proopiomelanocortin (POMC) neurons of the hypothalamic arcuate nucleus are essential regulators of energy balance. Selective loss of POMC production in these cells results in extreme obesity and metabolic comorbidities. Neurogenesis occurs in the adult hypothalamus, but it remains uncertain whether functional POMC neurons emerge in physiologically significant numbers during adulthood. Here, we tested whether Rax-expressing precursors generate POMC neurons in adult mice and rescue the metabolic phenotype caused by congenital hypothalamic POMC deficiency. METHODS Initially, we identified hypothalamic Rax-expressing cell types using wild-type and Rax-CreERT2:Ai34D mice. Then we generated compound Rax-CreERT2:ArcPomcloxTB/loxTB mice in which endogenous hypothalamic Pomc expression is silenced, but can be restored by tamoxifen administration selectively in neurons derived from Rax+ progenitors. The number of POMC neurons generated by Rax+ progenitors in adult mice and their axonal projections was determined. The metabolic effects of these neurons were assessed by measuring food intake, bodyweight, and body composition, along with glucose and insulin levels. RESULTS We found that Rax is expressed by tanycytes and a previously unrecognized cell type in the hypothalamic parenchyma of adult mice. Rax+ progenitors generated ~10% of the normal adult hypothalamic POMC neuron population within two weeks of tamoxifen treatment. The same rate and steady state of POMC neurogenesis persisted from young adult to aged mice. These new POMC neurons established terminal projections to brain regions that were involved in energy homeostasis. Mice with Rax+ progenitor-derived POMC neurons had reduced body fat mass, improved glucose tolerance, increased insulin sensitivity, and decreased bodyweight in proportion to the number of new POMC neurons. CONCLUSIONS These data demonstrate that Rax+ progenitors generate POMC neurons in sufficient numbers during adulthood to mitigate the metabolic abnormalities of hypothalamic POMC-deficient mice. The findings suggest that adult hypothalamic neurogenesis is a robust phenomenon in mice that can significantly impact energy homeostasis.
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Affiliation(s)
- Surbhi
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, 2800 Plymouth Rd, Ann Arbor, MI, 48109, USA.
| | - Gábor Wittmann
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tufts Medical Center, 800 Washington St, Boston, MA, 02111, USA.
| | - Malcolm J Low
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, 2800 Plymouth Rd, Ann Arbor, MI, 48109, USA.
| | - Ronald M Lechan
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tufts Medical Center, 800 Washington St, Boston, MA, 02111, USA.
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17
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Chatterjee O, Gopalakrishnan L, Mol P, Advani J, Nair B, Shankar SK, Mahadevan A, Prasad TSK. The Normal Human Adult Hypothalamus Proteomic Landscape: Rise of Neuroproteomics in Biological Psychiatry and Systems Biology. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2021; 25:693-710. [PMID: 34714154 DOI: 10.1089/omi.2021.0158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The human hypothalamus is central to the regulation of neuroendocrine and neurovegetative systems, as well as modulation of chronobiology and behavioral aspects in human health and disease. Surprisingly, a deep proteomic analysis of the normal human hypothalamic proteome has been missing for such an important organ so far. In this study, we delineated the human hypothalamus proteome using a high-resolution mass spectrometry approach which resulted in the identification of 5349 proteins, while a multiple post-translational modification (PTM) search identified 191 additional proteins, which were missed in the first search. A proteogenomic analysis resulted in the discovery of multiple novel protein-coding regions as we identified proteins from noncoding regions (pseudogenes) and proteins translated from short open reading frames that can be missed using the traditional pipeline of prediction of protein-coding genes as a part of genome annotation. We also identified several PTMs of hypothalamic proteins that may be required for normal hypothalamic functions. Moreover, we observed an enrichment of proteins pertaining to autophagy and adult neurogenesis in the proteome data. We believe that the hypothalamic proteome reported herein would help to decipher the molecular basis for the diverse range of physiological functions attributed to it, as well as its role in neurological and psychiatric diseases. Extensive proteomic profiling of the hypothalamic nuclei would further elaborate on the role and functional characterization of several hypothalamus-specific proteins and pathways to inform future research and clinical discoveries in biological psychiatry, neurology, and system biology.
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Affiliation(s)
- Oishi Chatterjee
- Institute of Bioinformatics, Bangalore India.,Amrita School of Biotechnology, Amrita University, Kollam, India.,Center for Systems Biology and Molecular Medicine, Yenepoya Research Center, Yenepoya (Deemed to be University), Mangalore, India
| | - Lathika Gopalakrishnan
- Institute of Bioinformatics, Bangalore India.,Center for Systems Biology and Molecular Medicine, Yenepoya Research Center, Yenepoya (Deemed to be University), Mangalore, India.,Manipal Academy of Higher Education, Manipal, India
| | - Praseeda Mol
- Institute of Bioinformatics, Bangalore India.,Amrita School of Biotechnology, Amrita University, Kollam, India
| | | | - Bipin Nair
- Amrita School of Biotechnology, Amrita University, Kollam, India
| | - Susarla Krishna Shankar
- Department of Neuropathology, National Institute of Mental Health and Neurosciences, Bangalore, India.,Human Brain Tissue Repository, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Anita Mahadevan
- Department of Neuropathology, National Institute of Mental Health and Neurosciences, Bangalore, India.,Human Brain Tissue Repository, National Institute of Mental Health and Neurosciences, Bangalore, India
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18
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Torres DJ, Pitts MW, Seale LA, Hashimoto AC, An KJ, Hanato AN, Hui KW, Remigio SMA, Carlson BA, Hatfield DL, Berry MJ. Female Mice with Selenocysteine tRNA Deletion in Agrp Neurons Maintain Leptin Sensitivity and Resist Weight Gain While on a High-Fat Diet. Int J Mol Sci 2021; 22:ijms222011010. [PMID: 34681674 PMCID: PMC8539086 DOI: 10.3390/ijms222011010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 11/16/2022] Open
Abstract
The role of the essential trace element selenium in hypothalamic physiology has begun to come to light over recent years. Selenium is used to synthesize a family of proteins participating in redox reactions called selenoproteins, which contain a selenocysteine residue in place of a cysteine. Past studies have shown that disrupted selenoprotein expression in the hypothalamus can adversely impact energy homeostasis. There is also evidence that selenium supports leptin signaling in the hypothalamus by maintaining proper redox balance. In this study, we generated mice with conditional knockout of the selenocysteine tRNA[Ser]Sec gene (Trsp) in an orexigenic cell population called agouti-related peptide (Agrp)-positive neurons. We found that female TrspAgrpKO mice gain less weight while on a high-fat diet, which occurs due to changes in adipose tissue activity. Female TrspAgrpKO mice also retained hypothalamic sensitivity to leptin administration. Male mice were unaffected, however, highlighting the sexually dimorphic influence of selenium on neurobiology and energy homeostasis. These findings provide novel insight into the role of selenoproteins within a small yet heavily influential population of hypothalamic neurons.
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Affiliation(s)
- Daniel J. Torres
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA; (L.A.S.); (M.J.B.)
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
- Correspondence:
| | - Matthew W. Pitts
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Lucia A. Seale
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA; (L.A.S.); (M.J.B.)
| | - Ann C. Hashimoto
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Katlyn J. An
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Ashley N. Hanato
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Katherine W. Hui
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Stella Maris A. Remigio
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA; (M.W.P.); (A.C.H.); (K.J.A.); (A.N.H.); (K.W.H.); (S.M.A.R.)
| | - Bradley A. Carlson
- Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (B.A.C.); (D.L.H.)
| | - Dolph L. Hatfield
- Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (B.A.C.); (D.L.H.)
| | - Marla J. Berry
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA; (L.A.S.); (M.J.B.)
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19
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Endothelial peroxynitrite causes disturbance of neuronal oscillations by targeting caspase-1 in the arcuate nucleus. Redox Biol 2021; 47:102147. [PMID: 34601428 PMCID: PMC8495174 DOI: 10.1016/j.redox.2021.102147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/13/2021] [Accepted: 09/20/2021] [Indexed: 02/08/2023] Open
Abstract
Severe anorexia limits the clinical application of cisplatin, and even leads to the discontinuation of treatment. However, the mechanisms underlying cisplatin-induced anorexia are unknown. Herein, we demonstrated that cisplatin could affect neuronal gamma oscillations and induce abnormal neuronal theta-gamma phase-amplitude coupling in the arcuate nucleus (Arc) of the hypothalamus, and these findings were associated with significantly decreased food intake and weight loss in mice. Chemogenetic activation of AgRP neurons in the Arc reversed the cisplatin-induced food intake reduction in mice. We further demonstrated that endothelial peroxynitrite (ONOO−) formation in the Arc induced nitrosative stress following cisplatin treatment via a previously uncharacterized pathway involving neuronal caspase-1 activation. Strikingly, treatment with the ONOO− scavenger uric acid (UA) reversed the reduced action potential (AP) frequency of AgRP neurons and increased the AP frequency of POMC neurons induced by SIN1, a donor of ONOO−, in the Arc, as determined by whole-cell patch-clamp electrophysiological recording. Consistent with these findings, UA treatment effectively alleviated cisplatin-induced dysfunction of neuronal oscillations and neuronal theta-gamma phase-amplitude coupling in the Arc of mice. Taken together, these results suggest, for the first time, that targeting the overproduction of endothelial ONOO− can regulate cisplatin-induced neurotoxicity through neuronal caspase-1, and thereby serve as a potential therapeutic approach to alleviate chemotherapy-induced anorexia and weight loss. Endothelial ONOO– induced the abnormal neuronal oscillations following cisplatin treatment through caspase-1 in the Arc. ONOO– scavenger UA could attenuate cisplatin-induced neurotoxicity and caspase-1 activation in the Arc. Targeting endothelial ONOO– provided a promising approach to alleviate chemotherapy-induced anorexia and weight loss.
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20
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Duquenne M, Folgueira C, Bourouh C, Millet M, Silva A, Clasadonte J, Imbernon M, Fernandois D, Martinez-Corral I, Kusumakshi S, Caron E, Rasika S, Deliglia E, Jouy N, Oishi A, Mazzone M, Trinquet E, Tavernier J, Kim YB, Ory S, Jockers R, Schwaninger M, Boehm U, Nogueiras R, Annicotte JS, Gasman S, Dam J, Prévot V. Leptin brain entry via a tanycytic LepR-EGFR shuttle controls lipid metabolism and pancreas function. Nat Metab 2021; 3:1071-1090. [PMID: 34341568 PMCID: PMC7611554 DOI: 10.1038/s42255-021-00432-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 06/23/2021] [Indexed: 01/14/2023]
Abstract
Metabolic health depends on the brain's ability to control food intake and nutrient use versus storage, processes that require peripheral signals such as the adipocyte-derived hormone, leptin, to cross brain barriers and mobilize regulatory circuits. We have previously shown that hypothalamic tanycytes shuttle leptin into the brain to reach target neurons. Here, using multiple complementary models, we show that tanycytes express functional leptin receptor (LepR), respond to leptin by triggering Ca2+ waves and target protein phosphorylation, and that their transcytotic transport of leptin requires the activation of a LepR-EGFR complex by leptin and EGF sequentially. Selective deletion of LepR in tanycytes blocks leptin entry into the brain, inducing not only increased food intake and lipogenesis but also glucose intolerance through attenuated insulin secretion by pancreatic β-cells, possibly via altered sympathetic nervous tone. Tanycytic LepRb-EGFR-mediated transport of leptin could thus be crucial to the pathophysiology of diabetes in addition to obesity, with therapeutic implications.
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Affiliation(s)
- Manon Duquenne
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Cintia Folgueira
- Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Cyril Bourouh
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, CNRS, U1283-UMR 8199-EGID, Lille, France
| | - Marion Millet
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Anisia Silva
- Institut Cochin, Inserm U1016, CNRS UMR 8104, University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Jérôme Clasadonte
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Monica Imbernon
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Daniela Fernandois
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Ines Martinez-Corral
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Soumya Kusumakshi
- Experimental Pharmacology, Center for Molecular Signaling, Saarland University School of Medicine, Homburg, Germany
| | - Emilie Caron
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - S Rasika
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Eleonora Deliglia
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Nathalie Jouy
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
- Flow Cytometry Core Facility, BioImaging Center of Lille, Hospital Campus, UMS2014-US41, Lille, France
| | - Asturo Oishi
- Institut Cochin, Inserm U1016, CNRS UMR 8104, University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Massimiliano Mazzone
- Laboratory of Tumor Inflammation and Angiogenesis, Center for Cancer Biology, VIB, Department of Oncology, Leuven, Belgium
| | - Eric Trinquet
- Cisbio Bioassays, Parc Technologique Marcel Boiteux, Codolet, France
| | - Jan Tavernier
- VIB-UGent Center for Medical Biotechnology, Gent, Belgium
| | - Young-Bum Kim
- Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Stéphane Ory
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Ralf Jockers
- Institut Cochin, Inserm U1016, CNRS UMR 8104, University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Ulrich Boehm
- Experimental Pharmacology, Center for Molecular Signaling, Saarland University School of Medicine, Homburg, Germany
| | - Ruben Nogueiras
- Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Jean-Sébastien Annicotte
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, CNRS, U1283-UMR 8199-EGID, Lille, France
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Julie Dam
- Institut Cochin, Inserm U1016, CNRS UMR 8104, University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Vincent Prévot
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France.
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21
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Heiss CN, Mannerås-Holm L, Lee YS, Serrano-Lobo J, Håkansson Gladh A, Seeley RJ, Drucker DJ, Bäckhed F, Olofsson LE. The gut microbiota regulates hypothalamic inflammation and leptin sensitivity in Western diet-fed mice via a GLP-1R-dependent mechanism. Cell Rep 2021; 35:109163. [PMID: 34038733 DOI: 10.1016/j.celrep.2021.109163] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 04/06/2021] [Accepted: 04/29/2021] [Indexed: 12/14/2022] Open
Abstract
Mice lacking a microbiota are protected from diet-induced obesity. Previous studies have shown that feeding a Western diet causes hypothalamic inflammation, which in turn can lead to leptin resistance and weight gain. Here, we show that wild-type (WT) mice with depleted gut microbiota, i.e., germ-free (GF) and antibiotic-treated mice, have elevated levels of glucagon-like peptide-1 (GLP-1), are protected against diet-induced hypothalamic inflammation, and have enhanced leptin sensitivity when fed a Western diet. Using GLP-1 receptor (GLP-1R)-deficient mice and pharmacological inhibition of the GLP-1R in WT mice, we demonstrate that intact GLP-1R signaling is required for preventing hypothalamic inflammation and enhancing leptin sensitivity. Furthermore, we show that astrocytes express the GLP-1R, and deletion of the receptor in glial fibrillary acidic protein (GFAP)-expressing cells diminished the antibiotic-induced protection against diet-induced hypothalamic inflammation. Collectively, our results suggest that depletion of the gut microbiota attenuates diet-induced hypothalamic inflammation and enhances leptin sensitivity via GLP-1R-dependent mechanisms.
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Affiliation(s)
- Christina N Heiss
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Louise Mannerås-Holm
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Ying Shiuan Lee
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Julia Serrano-Lobo
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Anna Håkansson Gladh
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Randy J Seeley
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Daniel J Drucker
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, ON M5G 1X5, Canada
| | - Fredrik Bäckhed
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden; Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Metabolic Receptology and Enteroendocrinology, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Department of Clinical Physiology, Region Västra Götaland, Sahlgrenska University Hospital, 41345 Gothenburg, Sweden
| | - Louise E Olofsson
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, 41345 Gothenburg, Sweden.
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22
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Amato AA, Wheeler HB, Blumberg B. Obesity and endocrine-disrupting chemicals. Endocr Connect 2021; 10:R87-R105. [PMID: 33449914 PMCID: PMC7983487 DOI: 10.1530/ec-20-0578] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/06/2021] [Indexed: 12/13/2022]
Abstract
Obesity is now a worldwide pandemic. The usual explanation given for the prevalence of obesity is that it results from consumption of a calorie dense diet coupled with physical inactivity. However, this model inadequately explains rising obesity in adults and in children over the past few decades, indicating that other factors must be important contributors. An endocrine-disrupting chemical (EDC) is an exogenous chemical, or mixture that interferes with any aspect of hormone action. EDCs have become pervasive in our environment, allowing humans to be exposed daily through ingestion, inhalation, and direct dermal contact. Exposure to EDCs has been causally linked with obesity in model organisms and associated with obesity occurrence in humans. Obesogens promote adipogenesis and obesity, in vivo, by a variety of mechanisms. The environmental obesogen model holds that exposure to obesogens elicits a predisposition to obesity and that such exposures may be an important yet overlooked factor in the obesity pandemic. Effects produced by EDCs and obesogen exposure may be passed to subsequent, unexposed generations. This "generational toxicology" is not currently factored into risk assessment by regulators but may be another important factor in the obesity pandemic as well as in the worldwide increases in the incidence of noncommunicable diseases that plague populations everywhere. This review addresses the current evidence on how obesogens affect body mass, discusses long-known chemicals that have been more recently identified as obesogens, and how the accumulated knowledge can help identify EDCs hazards.
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Affiliation(s)
- Angelica Amorim Amato
- Department of Pharmaceutical Sciences, University of Brasilia, Brasilia, Brazil
- Department of Developmental and Cell Biology, University of California, Irvine, California, USA
| | - Hailey Brit Wheeler
- Department of Developmental and Cell Biology, University of California, Irvine, California, USA
| | - Bruce Blumberg
- Department of Developmental and Cell Biology, University of California, Irvine, California, USA
- Department of Pharmaceutical Sciences, University of California, Irvine, California, USA
- Department of Biomedical Engineering, University of California, Irvine, California, USA
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23
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Tanycytes in the infundibular nucleus and median eminence and their role in the blood-brain barrier. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:253-273. [PMID: 34225934 DOI: 10.1016/b978-0-12-820107-7.00016-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The blood-brain barrier is generally attributed to endothelial cells. However, in circumventricular organs, such as the median eminence, tanycytes take over the barrier function. These ependymoglial cells form the wall of the third ventricle and send long extensions into the parenchyma to contact blood vessels and hypothalamic neurons. The shape and location of tanycytes put them in an ideal position to connect the periphery with central nervous compartments. In line with this, tanycytes control the transport of hormones and key metabolites in and out of the hypothalamus. They function as sensors of peripheral homeostasis for central regulatory networks. This chapter discusses current evidence that tanycytes play a key role in regulating glucose balance, food intake, endocrine axes, seasonal changes, reproductive function, and aging. The understanding of how tanycytes perform these diverse tasks is only just beginning to emerge and will probably lead to a more differentiated view of how the brain and the periphery interact.
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24
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Liang J, Jia Y, Yan H, Shen Q, Bian W, Zhao D, Xu Y, Jin Y, Yang M. Prdm16-Mediated Browning is Involved in Resistance to Diet-Induced and Monosodium Glutamate-Induced Obesity. Diabetes Metab Syndr Obes 2021; 14:4351-4360. [PMID: 34737591 PMCID: PMC8558318 DOI: 10.2147/dmso.s335526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/14/2021] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To investigate resistance to diet-induced obesity (DIO) and monosodium glutamate (MSG)-induced obesity as well as the underlying mechanisms. METHODS Newborn mice were used to construct DIO and MSG-induced obesity models. Obesity indices, such as body weight, body length, Lee index, body temperature, food intake, fat weight, and leptin level, were examined. Mice that did not exhibit obesity were defined as the obesity-resistant group. The morphological changes of white adipose tissue were observed by hematoxylin and eosin staining, and expression levels of PR domain containing 16 (Prdm16) and uncoupling protein-1 (Ucp-1) in white adipose tissue were measured by Western blot. RESULTS Obesity-resistant mice fed a high-fat diet showed resistance beginning at week 5 along with lower weights and lengths than those in the obesity group from weeks 5 to 12. MSG-induced obesity-resistant mice showed features consistent with resistance to obesity from week 1 along with higher body lengths relative to the obesity group; however, the weight difference was not significant until week 10, when body weights decreased significantly in obesity-resistant mice. The Lee index was lower in obesity-resistant mice than in the obesity group and the normal group, further suggesting obesity resistance. Additionally, obesity-resistant mice showed higher levels of leptin, whereas obese mice induced by a high-fat diet showed leptin resistance. Furthermore, Prdm16 and Ucp-1 levels were both downregulated in the obesity group and upregulated in obesity-resistant mice, showing that white fat browning was highest in obesity-resistant mice. CONCLUSION The phenotypes of mice with DIO and MSG-induced obesity differed. Obesity resistance might be related to Prdm16 and Ucp-1-mediated white adipocyte browning.
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Affiliation(s)
- Jia Liang
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Ying Jia
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Haijing Yan
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Qingyu Shen
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Weihua Bian
- Department of Cell Biology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Dongmei Zhao
- Department of Anatomy, Binzhou Medical University, Yantai, People’s Republic of China
| | - Yong Xu
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Yongjun Jin
- Department of Endocrinology, Binzhou Medical University, Yantai, People’s Republic of China
| | - Meizi Yang
- Department of Pharmacology, Binzhou Medical University, Yantai, People’s Republic of China
- Correspondence: Meizi Yang; Yongjun Jin Department of Pharmacology, Binzhou Medical University, Yantai, 264003, People’s Republic of ChinaTel +86 535 691 9507Fax +86 535 691 3163 Email ;
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25
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Schlagal CR, Wu P. Alcohol and Cocaine Combined Substance Use on Adult Hypothalamic Neural Stem Cells and Neurogenesis. Brain Plast 2020; 6:41-46. [PMID: 33680845 PMCID: PMC7903003 DOI: 10.3233/bpl-190091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Many advancements have been made over the years looking at the individual and combined effects of drugs of abuse on the brain, with one key area of research focusing on the effects on neurogenesis. An integral part of fetal brain development and, later, maintenance in the adult brain, neurogenesis occurs in three main regions: subventricularzone of the lateral ventricles (SVZ), subgranularzone of the dentate gyrus (SGZ), and the tanycyte layer in the hypothalamus (TL). We will review current literature on combined drugs of abuse and their effect on adult neurogenesis. More specifically, this review will focus on the effect of combining cocaine and alcohol. Additionally, the tanycyte layer will be explored in more depth and probed to look at the neurogenic properties of tanycytes and their role in neurogenesis.
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Affiliation(s)
- Caitlin R Schlagal
- Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, USA
| | - Ping Wu
- Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, USA
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26
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Bayne M, Alvarsson A, Devarakonda K, Li R, Jimenez-Gonzalez M, Garibay D, Conner K, Varghese M, Serasinghe MN, Chipuk JE, Hof PR, Stanley SA. Repeated hypoglycemia remodels neural inputs and disrupts mitochondrial function to blunt glucose-inhibited GHRH neuron responsiveness. JCI Insight 2020; 5:133488. [PMID: 33148883 PMCID: PMC7710320 DOI: 10.1172/jci.insight.133488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 09/24/2020] [Indexed: 11/29/2022] Open
Abstract
Hypoglycemia is a frequent complication of diabetes, limiting therapy and increasing morbidity and mortality. With recurrent hypoglycemia, the counterregulatory response (CRR) to decreased blood glucose is blunted, resulting in hypoglycemia-associated autonomic failure (HAAF). The mechanisms leading to these blunted effects are only poorly understood. Here, we report, with ISH, IHC, and the tissue-clearing capability of iDISCO+, that growth hormone releasing hormone (GHRH) neurons represent a unique population of arcuate nucleus neurons activated by glucose deprivation in vivo. Repeated glucose deprivation reduces GHRH neuron activation and remodels excitatory and inhibitory inputs to GHRH neurons. We show that low glucose sensing is coupled to GHRH neuron depolarization, decreased ATP production, and mitochondrial fusion. Repeated hypoglycemia attenuates these responses during low glucose. By maintaining mitochondrial length with the small molecule mitochondrial division inhibitor-1, we preserved hypoglycemia sensitivity in vitro and in vivo. Our findings present possible mechanisms for the blunting of the CRR, significantly broaden our understanding of the structure of GHRH neurons, and reveal that mitochondrial dynamics play an important role in HAAF. We conclude that interventions targeting mitochondrial fission in GHRH neurons may offer a new pathway to prevent HAAF in patients with diabetes. GHRH neurons in the arcuate nucleus are activated by glucose deprivation; however, repeated hypoglycemia blunts activation, remodels inputs, and disrupts mitochondrial fusion.
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Affiliation(s)
| | | | | | | | | | | | | | - Merina Varghese
- Nash Family Department of Neuroscience and Friedman Brain Institute, and
| | - Madhavika N Serasinghe
- Tisch Cancer Institute and Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jerry E Chipuk
- Tisch Cancer Institute and Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, and
| | - Sarah A Stanley
- Diabetes, Obesity and Metabolism Institute.,Nash Family Department of Neuroscience and Friedman Brain Institute, and
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27
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Augustine V, Lee S, Oka Y. Neural Control and Modulation of Thirst, Sodium Appetite, and Hunger. Cell 2020; 180:25-32. [PMID: 31923398 DOI: 10.1016/j.cell.2019.11.040] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/13/2019] [Accepted: 11/27/2019] [Indexed: 01/01/2023]
Abstract
The function of central appetite neurons is instructing animals to ingest specific nutrient factors that the body needs. Emerging evidence suggests that individual appetite circuits for major nutrients-water, sodium, and food-operate on unique driving and quenching mechanisms. This review focuses on two aspects of appetite regulation. First, we describe the temporal relationship between appetite neuron activity and consumption behaviors. Second, we summarize ingestion-related satiation signals that differentially quench individual appetite circuits. We further discuss how distinct appetite and satiation systems for each factor may contribute to nutrient homeostasis from the functional and evolutional perspectives.
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Affiliation(s)
- Vineet Augustine
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA; Department of Neuroscience, The Scripps Research Institute, La Jolla, California, USA
| | - Sangjun Lee
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA
| | - Yuki Oka
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.
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28
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Venema W, Severi I, Perugini J, Di Mercurio E, Mainardi M, Maffei M, Cinti S, Giordano A. Ciliary Neurotrophic Factor Acts on Distinctive Hypothalamic Arcuate Neurons and Promotes Leptin Entry Into and Action on the Mouse Hypothalamus. Front Cell Neurosci 2020; 14:140. [PMID: 32528252 PMCID: PMC7253709 DOI: 10.3389/fncel.2020.00140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 04/24/2020] [Indexed: 12/13/2022] Open
Abstract
In humans and experimental animals, the administration of ciliary neurotrophic factor (CNTF) reduces food intake and body weight. To gain further insights into the mechanism(s) underlying its satiety effect, we: (i) evaluated the CNTF-dependent activation of the Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) pathway in mouse models where neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) neurons can be identified by green fluorescent protein (GFP); and (ii) assessed whether CNTF promotes leptin signaling in hypothalamic feeding centers. Immunohistochemical experiments enabled us to establish that intraperitoneal injection of mouse recombinant CNTF activated the JAK2-STAT3 pathway in a substantial proportion of arcuate nucleus (ARC) NPY neurons (18.68% ± 0.60 in 24-h fasted mice and 25.50% ± 1.17 in fed mice) but exerted a limited effect on POMC neurons (4.15% ± 0.33 in 24-h fasted mice and 2.84% ± 0.45 in fed mice). CNTF-responsive NPY neurons resided in the ventromedial ARC, facing the median eminence (ME), and were surrounded by albumin immunoreactivity, suggesting that they are located outside the blood-brain barrier (BBB). In both normally fed and high-fat diet (HFD) obese animals, CNTF activated extracellular signal-regulated kinase signaling in ME β1- and β2-tanycytes, an effect that has been linked to the promotion of leptin entry into the brain. Accordingly, compared to the animals treated with leptin, mice treated with leptin/CNTF showed: (i) a significantly greater leptin content in hypothalamic protein extracts; (ii) a significant increase in phospho-STAT3 (P-STAT3)-positive neurons in the ARC and the ventromedial hypothalamic nucleus of normally fed mice; and (iii) a significantly increased number of P-STAT3-positive neurons in the ARC and dorsomedial hypothalamic nucleus of HFD obese mice. Collectively, these data suggest that exogenously administered CNTF reduces food intake by exerting a leptin-like action on distinctive NPY ARC neurons and by promoting leptin signaling in hypothalamic feeding centers.
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Affiliation(s)
- Wiebe Venema
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy
| | - Ilenia Severi
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy
| | - Jessica Perugini
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy
| | - Eleonora Di Mercurio
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy
| | - Marco Mainardi
- Institute of Neuroscience, National Research Council, Pisa, Italy
| | | | - Saverio Cinti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy.,Center of Obesity, Università Politecnica delle Marche-United Hospitals, Ancona, Italy
| | - Antonio Giordano
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica Delle Marche, Ancona, Italy
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29
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Ibars M, Maier MT, Yulyaningsih E, Perez L, Cheang R, Vilhelmsson A, Louie SM, Wegner SA, Yuan X, Eltzschig HK, Hopf FW, Nomura DK, Koliwad SK, Xu AW. Neuronal modulation of hepatic lipid accumulation induced by bingelike drinking. Am J Physiol Endocrinol Metab 2020; 318:E655-E666. [PMID: 32045262 PMCID: PMC7272724 DOI: 10.1152/ajpendo.00218.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 12/20/2022]
Abstract
Excessive alcohol consumption, including binge drinking, is a common cause of fatty liver disease. Binge drinking rapidly induces hepatic steatosis, an early step in the pathogenesis of chronic liver injury. Despite its prevalence, the process by which excessive alcohol consumption promotes hepatic lipid accumulation remains unclear. Alcohol exerts potent effects on the brain, including hypothalamic neurons crucial for metabolic regulation. However, whether or not the brain plays a role in alcohol-induced hepatic steatosis is unknown. In the brain, alcohol increases extracellular levels of adenosine, a potent neuromodulator, and previous work implicates adenosine signaling as being important for the development of alcoholic fatty liver disease. Acute alcohol exposure also increases both the activity of agouti-related protein (AgRP)-expressing neurons and AgRP immunoreactivity. Here, we show that adenosine receptor A2B signaling in the brain modulates the extent of alcohol-induced fatty liver in mice and that both the AgRP neuropeptide and the sympathetic nervous system are indispensable for hepatic steatosis induced by bingelike alcohol consumption. Together, these results indicate that the brain plays an integral role in alcohol-induced hepatic lipid accumulation and that central adenosine signaling, hypothalamic AgRP, and the sympathetic nervous system are crucial mediators of this process.
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Affiliation(s)
- Maria Ibars
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Matthew T Maier
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Ernie Yulyaningsih
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Luz Perez
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Rachel Cheang
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Anna Vilhelmsson
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
| | - Sharon M Louie
- Departments of Chemistry, Molecular and Cell Biology, and Nutritional Sciences and Toxicology, University of California, Berkeley, California
| | - Scott A Wegner
- Department of Neurology, Department of Anatomy, University of California, San Francisco, California
| | - Xiaoyi Yuan
- Department of Anesthesiology, University of Texas Health Science Center at Houston, Houston, Texas
| | - Holger K Eltzschig
- Department of Anesthesiology, University of Texas Health Science Center at Houston, Houston, Texas
| | - Frederic W Hopf
- Department of Neurology, Department of Anatomy, University of California, San Francisco, California
| | - Daniel K Nomura
- Departments of Chemistry, Molecular and Cell Biology, and Nutritional Sciences and Toxicology, University of California, Berkeley, California
| | - Suneil K Koliwad
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
- Department of Medicine, Department of Anatomy, University of California, San Francisco, California
| | - Allison W Xu
- Diabetes Center, Department of Anatomy, University of California, San Francisco, California
- Department of Anatomy, University of California, San Francisco, California
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30
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Abstract
Food intake and energy homeostasis determine survival of the organism and species. Information on total energy levels and metabolic state are sensed in the periphery and transmitted to the brain, where it is integrated and triggers the animal to forage, prey, and consume food. Investigating circuitry and cellular mechanisms coordinating energy balance and feeding behaviors has drawn on many state-of-the-art techniques, including gene manipulation, optogenetics, virus tracing, and single-cell sequencing. These new findings provide novel insights into how the central nervous system regulates food intake, and shed the light on potential therapeutic interventions for eating-related disorders such as obesity and anorexia.
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31
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Obesity: Pathophysiology, monosodium glutamate-induced model and anti-obesity medicinal plants. Biomed Pharmacother 2019; 111:503-516. [DOI: 10.1016/j.biopha.2018.12.108] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 12/13/2018] [Accepted: 12/23/2018] [Indexed: 02/08/2023] Open
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32
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Recabal A, Elizondo-Vega R, Philippot C, Salgado M, López S, Palma A, Tarifeño-Saldivia E, Timmermann A, Seifert G, Caprile T, Steinhäuser C, García-Robles MA. Connexin-43 Gap Junctions Are Responsible for the Hypothalamic Tanycyte-Coupled Network. Front Cell Neurosci 2018; 12:406. [PMID: 30534054 PMCID: PMC6275304 DOI: 10.3389/fncel.2018.00406] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/19/2018] [Indexed: 12/21/2022] Open
Abstract
Tanycytes are hypothalamic radial glia-like cells that form the basal wall of the third ventricle (3V) where they sense glucose and modulate neighboring neuronal activity to control feeding behavior. This role requires the coupling of hypothalamic cells since transient decreased hypothalamic Cx43 expression inhibits the increase of brain glucose-induced insulin secretion. Tanycytes have been postulated as possible hypothalamic neuronal precursors due to their privileged position in the hypothalamus that allows them to detect mitogenic signals and because they share the markers and characteristics of neuronal precursors located in other neurogenic niches, including the formation of coupled networks through connexins. Using wild-type (WT), Cx30−/– and Cx30−/–, Cx43fl/fl:glial fibrillary acidic protein (GFAP)-Cre (double knockout, dKO) mouse lines, we demonstrated that tanycytes are highly coupled to each other and also give rise to a panglial network specifically through Cx43. Using the human GFAP (hGFAP)-enhanced green fluorescent protein (EGFP) transgenic mouse line, we provided evidence that the main parenchymal-coupled cells were astrocytes. In addition, electrophysiological parameters, such as membrane resistance, were altered when Cx43 was genetically absent or pharmacologically inhibited. Finally, in the dKO mouse line, we detected a significant decrease in the number of hypothalamic proliferative parenchymal cells. Our results demonstrate the importance of Cx43 in tanycyte homotypic and panglial coupling and show that Cx43 function influences the proliferative potential of hypothalamic cells.
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Affiliation(s)
- Antonia Recabal
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Roberto Elizondo-Vega
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Camille Philippot
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn Bonn, Germany
| | - Magdiel Salgado
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Sergio López
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Alejandra Palma
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Estefanía Tarifeño-Saldivia
- Department of Biochemistry and Molecular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Aline Timmermann
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn Bonn, Germany
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn Bonn, Germany
| | - Teresa Caprile
- Department of Cellular Biology, Faculty of Biological Sciences, University of Concepcion Concepcion, Chile
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn Bonn, Germany
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33
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Abstract
The hypothalamus is the central neural site governing food intake and energy expenditure. During the past 25 years, understanding of the hypothalamic cell types, hormones, and circuitry involved in the regulation of energy metabolism has dramatically increased. It is now well established that the adipocyte-derived hormone, leptin, acts upon two distinct groups of hypothalamic neurons that comprise opposing arms of the central melanocortin system. These two cell populations are anorexigenic neurons expressing proopiomelanocortin (POMC) and orexigenic neurons that express agouti-related peptide (AGRP). Several important studies have demonstrated that reactive oxygen species and endoplasmic reticulum stress significantly impact these hypothalamic neuronal populations that regulate global energy metabolism. Reactive oxygen species and redox homeostasis are influenced by selenoproteins, an essential class of proteins that incorporate selenium co-translationally in the form of the 21st amino acid, selenocysteine. Levels of these proteins are regulated by dietary selenium intake and they are widely expressed in the brain. Of additional relevance, selenium supplementation has been linked to metabolic alterations in both animal and human studies. Recent evidence also indicates that hypothalamic selenoproteins are significant modulators of energy metabolism in both neurons and tanycytes, a population of glial-like cells lining the floor of the 3rd ventricle within the hypothalamus. This review article will summarize current understanding of the regulatory influence of redox status on hypothalamic nutrient sensing and highlight recent work revealing the importance of selenoproteins in the hypothalamus.
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Affiliation(s)
- Ting Gong
- Department of Molecular Biosciences and Bioengineering, University of Hawaii, Honolulu, HI 96813, USA
| | - Daniel J Torres
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA
| | - Marla J Berry
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA
| | - Matthew W Pitts
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA.
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Augustine V, Gokce SK, Oka Y. Peripheral and Central Nutrient Sensing Underlying Appetite Regulation. Trends Neurosci 2018; 41:526-539. [PMID: 29914721 DOI: 10.1016/j.tins.2018.05.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 04/30/2018] [Accepted: 05/01/2018] [Indexed: 12/11/2022]
Abstract
The precise regulation of fluid and energy homeostasis is essential for survival. It is well appreciated that ingestive behaviors are tightly regulated by both peripheral sensory inputs and central appetite signals. With recent neurogenetic technologies, considerable progress has been made in our understanding of basic taste qualities, the molecular and/or cellular basis of taste sensing, and the central circuits for thirst and hunger. In this review, we first highlight the functional similarities and differences between mammalian and invertebrate taste processing. We then discuss how central thirst and hunger signals interact with peripheral sensory signals to regulate ingestive behaviors. We finally indicate some of the directions for future research.
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Affiliation(s)
- Vineet Augustine
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Sertan Kutal Gokce
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Yuki Oka
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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Abstract
Bile acids facilitate dietary fat absorption upon release into the small intestine after a meal. A recent study by Liu and colleagues identifies a gut-brain axis wherein bile acids signal an energy-replete state to hypothalamic AgRP neurons via activation of neuronal FGF receptors, which orchestrate whole-body glucose metabolism.
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Affiliation(s)
- Allison W Xu
- Diabetes Center and Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA.
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Prevot V, Dehouck B, Sharif A, Ciofi P, Giacobini P, Clasadonte J. The Versatile Tanycyte: A Hypothalamic Integrator of Reproduction and Energy Metabolism. Endocr Rev 2018; 39:333-368. [PMID: 29351662 DOI: 10.1210/er.2017-00235] [Citation(s) in RCA: 147] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/12/2018] [Indexed: 12/16/2022]
Abstract
The fertility and survival of an individual rely on the ability of the periphery to promptly, effectively, and reproducibly communicate with brain neural networks that control reproduction, food intake, and energy homeostasis. Tanycytes, a specialized glial cell type lining the wall of the third ventricle in the median eminence of the hypothalamus, appear to act as the linchpin of these processes by dynamically controlling the secretion of neuropeptides into the portal vasculature by hypothalamic neurons and regulating blood-brain and blood-cerebrospinal fluid exchanges, both processes that depend on the ability of these cells to adapt their morphology to the physiological state of the individual. In addition to their barrier properties, tanycytes possess the ability to sense blood glucose levels, and play a fundamental and active role in shuttling circulating metabolic signals to hypothalamic neurons that control food intake. Moreover, accumulating data suggest that, in keeping with their putative descent from radial glial cells, tanycytes are endowed with neural stem cell properties and may respond to dietary or reproductive cues by modulating hypothalamic neurogenesis. Tanycytes could thus constitute the missing link in the loop connecting behavior, hormonal changes, signal transduction, central neuronal activation and, finally, behavior again. In this article, we will examine these recent advances in the understanding of tanycytic plasticity and function in the hypothalamus and the underlying molecular mechanisms. We will also discuss the putative involvement and therapeutic potential of hypothalamic tanycytes in metabolic and fertility disorders.
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Affiliation(s)
- Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France.,University of Lille, FHU 1000 Days for Health, School of Medicine, Lille, France
| | - Bénédicte Dehouck
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France.,University of Lille, FHU 1000 Days for Health, School of Medicine, Lille, France
| | - Ariane Sharif
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France.,University of Lille, FHU 1000 Days for Health, School of Medicine, Lille, France
| | - Philippe Ciofi
- Inserm, Neurocentre Magendie, Bordeaux, France.,Université de Bordeaux, Bordeaux, France
| | - Paolo Giacobini
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France.,University of Lille, FHU 1000 Days for Health, School of Medicine, Lille, France
| | - Jerome Clasadonte
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France.,University of Lille, FHU 1000 Days for Health, School of Medicine, Lille, France
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Maier MT, Vilhelmsson A, Louie SM, Vagena E, Nomura DK, Koliwad SK, Xu AW. Regulation of Hepatic Lipid Accumulation and Distribution by Agouti-Related Protein in Male Mice. Endocrinology 2018; 159:2408-2420. [PMID: 29750244 PMCID: PMC6692877 DOI: 10.1210/en.2018-00040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 05/02/2018] [Indexed: 12/30/2022]
Abstract
Proper regulation of energy metabolism requires neurons in the central nervous system to respond dynamically to signals that reflect the body's energy reserve, and one such signal is leptin. Agouti-related protein (AgRP) is a hypothalamic neuropeptide that is markedly upregulated in leptin deficiency, a condition that is associated with severe obesity, diabetes, and hepatic steatosis. Because deleting AgRP in mice does not alter energy balance, we sought to determine whether AgRP plays an indispensable role in regulating energy and hepatic lipid metabolism in the sensitized background of leptin deficiency. We generated male mice that are deficient for both leptin and AgRP [double-knockout (DKO)]. DKO mice and ob/ob littermates had similar body weights, food intake, energy expenditure, and plasma insulin levels, although DKO mice surprisingly developed heightened hyperglycemia with advancing age. Overall hepatic lipid content was reduced in young prediabetic DKO mice, but not in the older diabetic counterparts. Intriguingly, however, both young and older DKO mice had an altered zonal distribution of hepatic lipids with reduced periportal lipid deposition. Moreover, leptin stimulated, whereas AgRP inhibited, hepatic sympathetic activity. Ablating sympathetic nerves to the liver, which primarily innervate the portal regions, produced periportal lipid accumulation in wild-type mice. Collectively, our results highlight AgRP as a regulator of hepatic sympathetic activity and metabolic zonation.
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Affiliation(s)
- Matthew T Maier
- Diabetes Center, University of California, San Francisco, San Francisco, California
| | - Anna Vilhelmsson
- Diabetes Center, University of California, San Francisco, San Francisco, California
| | - Sharon M Louie
- Department of Chemistry, University of California, Berkeley, Berkeley, California
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, California
| | - Eirini Vagena
- Diabetes Center, University of California, San Francisco, San Francisco, California
| | - Daniel K Nomura
- Department of Chemistry, University of California, Berkeley, Berkeley, California
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, California
| | - Suneil K Koliwad
- Diabetes Center, University of California, San Francisco, San Francisco, California
- Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Allison W Xu
- Diabetes Center, University of California, San Francisco, San Francisco, California
- Department of Anatomy, University of California, San Francisco, San Francisco, California
- Correspondence: Allison W. Xu, PhD, Diabetes Center, University of California, San Francisco, San Francisco, Box 0534 , S-1222, California 94143, E-mail:
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38
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Yoo S, Blackshaw S. Regulation and function of neurogenesis in the adult mammalian hypothalamus. Prog Neurobiol 2018; 170:53-66. [PMID: 29631023 DOI: 10.1016/j.pneurobio.2018.04.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 02/20/2018] [Accepted: 04/05/2018] [Indexed: 12/11/2022]
Abstract
Over the past two decades, evidence has accumulated that neurogenesis can occur in both the juvenile and adult mammalian hypothalamus. Levels of hypothalamic neurogenesis can be regulated by dietary, environmental and hormonal signals. Since the hypothalamus has a central role in controlling a broad range of homeostatic physiological processes, these findings may have far ranging behavioral and medical implications. However, many questions in the field remain unresolved, including the cells of origin of newborn hypothalamic neurons and the extent to which these cells actually regulate hypothalamic-controlled behaviors. In this manuscript, we conduct a critical review of the literature on postnatal hypothalamic neurogenesis in mammals, lay out the main outstanding controversies in the field, and discuss how best to advance our knowledge of this fascinating but still poorly understood process.
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Affiliation(s)
- Sooyeon Yoo
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Center for Human Systems Biology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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