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Khan R, Laumet G, Leinninger GM. Hungry for relief: Potential for neurotensin to address comorbid obesity and pain. Appetite 2024; 200:107540. [PMID: 38852785 DOI: 10.1016/j.appet.2024.107540] [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: 02/01/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/11/2024]
Abstract
Chronic pain and obesity frequently occur together. An ideal therapy would alleviate pain without weight gain, and most optimally, could promote weight loss. The neuropeptide neurotensin (Nts) has been separately implicated in reducing weight and pain but could it be a common actionable target for both pain and obesity? Here we review the current knowledge of Nts signaling via its receptors in modulating body weight and pain processing. Evaluating the mechanism by which Nts impacts ingestive behavior, body weight, and analgesia has potential to identify common physiologic mechanisms underlying weight and pain comorbidities, and whether Nts may be common actionable targets for both.
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Affiliation(s)
- Rabail Khan
- Neuroscience Program, Michigan State University, East Lansing, MI, 48824, USA
| | - Geoffroy Laumet
- Neuroscience Program, Michigan State University, East Lansing, MI, 48824, USA; Department of Physiology, Michigan State University, East Lansing, MI, 48824, USA
| | - Gina M Leinninger
- Neuroscience Program, Michigan State University, East Lansing, MI, 48824, USA; Department of Physiology, Michigan State University, East Lansing, MI, 48824, USA.
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2
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Fessel J. All GLP-1 Agonists Should, Theoretically, Cure Alzheimer's Dementia but Dulaglutide Might Be More Effective Than the Others. J Clin Med 2024; 13:3729. [PMID: 38999294 PMCID: PMC11242057 DOI: 10.3390/jcm13133729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 06/25/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024] Open
Abstract
Addressing the dysfunctions of all brain cell types in Alzheimer's disease (AD) should cure the dementia, an objective that might be achieved by GLP-1 agonist drugs, because receptors for GLP-1 are present in all of the main brain cell types, i.e., neurons, oligodendroglia, astroglia, microglia, endothelial cells and pericytes. This article describes the benefits provided to all of those brain cell types by GLP-1 agonist drugs. The article uses studies in humans, not rodents, to describe the effect of GLP-1 agonists upon cognition, because rodents' brains differ from those of humans in so many ways that results from rodent studies may not be totally transferable to humans. Commercially available GLP-1 agonists have mostly shown either positive effects upon cognition or no effects. One important reason for no effects is a reduced rate of entering brain parenchyma. Dulaglutide has the greatest entry to brain, at 61.8%, among the available GLP-1 agonists, and seems to offer the best likelihood for cure of AD. Although there is only one study of cognition that used dulaglutide, it was randomized, placebo controlled, and very large; it involved 8828 participants and showed significant benefit to cognition. A clinical trial to test the hypothesis that dulaglutide may cure AD should have, as its primary outcome, a 30% greater cure rate of AD by dulaglutide than that achieved by an equipoise arm of, e.g., lithium plus memantine.
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Affiliation(s)
- Jeffrey Fessel
- Department of Medicine, University of California, 2069 Filbert Street, San Francisco, CA 94123, USA
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3
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Merkel R, Hernandez N, Weir V, Zhang Y, Rich MT, Crist RC, Reiner BC, Schmidt HD. An endogenous GLP-1 circuit engages VTA GABA neurons to regulate mesolimbic dopamine neurons and attenuate cocaine seeking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599574. [PMID: 38979354 PMCID: PMC11230186 DOI: 10.1101/2024.06.20.599574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Recent studies show that systemic administration of a glucagon-like peptide-1 receptor (GLP-1R) agonist is sufficient to attenuate the reinstatement of cocaine-seeking behavior, an animal model of relapse. However, the neural mechanisms mediating these effects and the role of endogenous central GLP-1 signaling in cocaine seeking remain unknown. Here, we show that voluntary cocaine taking decreased plasma GLP-1 levels in rats and that chemogenetic activation of GLP-1-producing neurons in the nucleus tractus solitarius (NTS) that project to the ventral tegmental area (VTA) decreased cocaine reinstatement. Single nuclei transcriptomics and FISH studies revealed GLP-1Rs are expressed primarily on GABA neurons in the VTA. Using in vivo fiber photometry, we found that the efficacy of a systemic GLP-1R agonist to attenuate cocaine seeking was associated with increased activity of VTA GABA neurons and decreased activity of VTA dopamine neurons. Together, these findings suggest that targeting central GLP-1 circuits may be an effective strategy toward reducing cocaine relapse and highlight a novel functional role of GABAergic GLP-1R-expressing midbrain neurons in drug seeking.
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4
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Mishra D, Richard JE, Maric I, Shevchouk OT, Börchers S, Eerola K, Krieger JP, Skibicka KP. Lateral parabrachial nucleus astrocytes control food intake. Front Endocrinol (Lausanne) 2024; 15:1389589. [PMID: 38887265 PMCID: PMC11180714 DOI: 10.3389/fendo.2024.1389589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 05/03/2024] [Indexed: 06/20/2024] Open
Abstract
Food intake behavior is under the tight control of the central nervous system. Most studies to date focus on the contribution of neurons to this behavior. However, although previously overlooked, astrocytes have recently been implicated to play a key role in feeding control. Most of the recent literature has focused on astrocytic contribution in the hypothalamus or the dorsal vagal complex. The contribution of astrocytes located in the lateral parabrachial nucleus (lPBN) to feeding behavior control remains poorly understood. Thus, here, we first investigated whether activation of lPBN astrocytes affects feeding behavior in male and female rats using chemogenetic activation. Astrocytic activation in the lPBN led to profound anorexia in both sexes, under both ad-libitum feeding schedule and after a fasting challenge. Astrocytes have a key contribution to glutamate homeostasis and can themselves release glutamate. Moreover, lPBN glutamate signaling is a key contributor to potent anorexia, which can be induced by lPBN activation. Thus, here, we determined whether glutamate signaling is necessary for lPBN astrocyte activation-induced anorexia, and found that pharmacological N-methyl D-aspartate (NMDA) receptor blockade attenuated the food intake reduction resulting from lPBN astrocyte activation. Since astrocytes have been shown to contribute to feeding control by modulating the feeding effect of peripheral feeding signals, we further investigated whether lPBN astrocyte activation is capable of modulating the anorexic effect of the gut/brain hormone, glucagon like peptide -1, as well as the orexigenic effect of the stomach hormone - ghrelin, and found that the feeding effect of both signals is modulated by lPBN astrocytic activation. Lastly, we found that lPBN astrocyte activation-induced anorexia is affected by a diet-induced obesity challenge, in a sex-divergent manner. Collectively, current findings uncover a novel role for lPBN astrocytes in feeding behavior control.
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Affiliation(s)
- Devesh Mishra
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jennifer E. Richard
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Ivana Maric
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Nutritional Sciences, Pennsylvania State University, University Park, PA, United States
| | - Olesya T. Shevchouk
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Stina Börchers
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Nutritional Sciences, Pennsylvania State University, University Park, PA, United States
| | - Kim Eerola
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Jean-Philippe Krieger
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Institute of Veterinary Pharmacology and Toxicology, University of Zurich - VetSuisse, Zurich, Switzerland
| | - Karolina P. Skibicka
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Nutritional Sciences, Pennsylvania State University, University Park, PA, United States
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
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5
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Chartoumpekis DV, Habeos EE, Psilopanagioti A. Evaluating the effectiveness and underlying mechanisms of incretin-based treatments for hypothalamic obesity: A narrative review. OBESITY PILLARS 2024; 10:100104. [PMID: 38463533 PMCID: PMC10924130 DOI: 10.1016/j.obpill.2024.100104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/18/2024] [Accepted: 02/19/2024] [Indexed: 03/12/2024]
Abstract
Background Hypothalamic obesity represents a clinical condition within the broader spectrum of obesity that frequently eludes detection and appropriate diagnosis. This subset of obesity is characterized by a dearth of established predictive markers and a paucity of standardized therapeutic protocols. The advent and rising prominence of glucagon-like peptide-1 (GLP-1) receptor agonists in the obesity treatment landscape present novel therapeutic avenues for hypothalamic obesity management. Nonetheless, critical inquiries persist concerning the efficacy of GLP-1 receptor (GLP-1R) agonists in this context, particularly regarding their central mechanisms of action and specific impact on hypothalamic obesity. Methods In this narrative review, we concentrate on analyzing research papers that delineate the detection and function of GLP-1 receptors across various hypothalamic and cerebral regions. Additionally, we examine clinical research papers and reports detailing the application of GLP-1 receptor agonists in treating hypothalamic obesity. Furthermore, we include a concise presentation of a clinical case from our unit for contextual understanding. Results Currently, the clinical evidence supporting the efficacy of GLP-1 receptor agonists in hypothalamic obesity, as well as the diverse characteristics of this obesity subtype, remains insufficient. Preliminary data suggest that GLP-1R agonists might offer an effective treatment option, albeit with variable outcomes, particularly in younger patient cohorts. From a mechanistic perspective, the presence of GLP-1 receptors in various hypothalamic and broader brain regions potentially underpins the efficacy of GLP-1R agonists, even in instances of hypothalamic damage. Nevertheless, additional research is imperative to establish the functional relevance of these receptors in said brain regions. Conclusion GLP-1R agonists represent a potential therapeutic option for patients with hypothalamic obesity. However, further clinical and basic/translational research is essential to validate the efficacy of these drugs across different presentations of hypothalamic obesity and to understand the functionality of GLP-1R in the diverse brain regions where they are expressed.
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Affiliation(s)
- Dionysios V Chartoumpekis
- Service of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital and University of Lausanne, CH-1011, Lausanne, Switzerland
| | - Evagelia E Habeos
- Division of Endocrinology, Department of Internal Medicine, University of Patras, GR-26504, Patras, Greece
| | - Aristea Psilopanagioti
- Division of Endocrinology, Department of Internal Medicine, University of Patras, GR-26504, Patras, Greece
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6
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Fessel J. Special Issue "Pathophysiology and Treatment of Alzheimer's Disease". Int J Mol Sci 2024; 25:6015. [PMID: 38892203 PMCID: PMC11173226 DOI: 10.3390/ijms25116015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Revised: 05/27/2024] [Accepted: 05/29/2024] [Indexed: 06/21/2024] Open
Abstract
The majority of clinical trials, whose primary aims were to moderate Alzheimer's dementia (AD), have been based upon the prevailing paradigm, i [...].
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Affiliation(s)
- Jeffrey Fessel
- Department of Medicine, University of California, San Francisco, 2069 Filbert Street, San Francisco, CA 94123, USA
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7
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Syvänen V, Koistinaho J, Lehtonen Š. Identification of the abnormalities in astrocytic functions as potential drug targets for neurodegenerative disease. Expert Opin Drug Discov 2024; 19:603-616. [PMID: 38409817 DOI: 10.1080/17460441.2024.2322988] [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: 10/26/2023] [Accepted: 02/21/2024] [Indexed: 02/28/2024]
Abstract
INTRODUCTION Historically, astrocytes were seen primarily as a supportive cell population within the brain; with neurodegenerative disease research focusing exclusively on malfunctioning neurons. However, astrocytes perform numerous tasks that are essential for maintenance of the central nervous system`s complex processes. Disruption of these functions can have negative consequences; hence, it is unsurprising to observe a growing amount of evidence for the essential role of astrocytes in the development and progression of neurodegenerative diseases. Targeting astrocytic functions may serve as a potential disease-modifying drug therapy in the future. AREAS COVERED The present review emphasizes the key astrocytic functions associated with neurodegenerative diseases and explores the possibility of pharmaceutical interventions to modify these processes. In addition, the authors provide an overview of current advancement in this field by including studies of possible drug candidates. EXPERT OPINION Glial research has experienced a significant renaissance in the last quarter-century. Understanding how disease pathologies modify or are caused by astrocyte functions is crucial when developing treatments for brain diseases. Future research will focus on building advanced models that can more precisely correlate to the state in the human brain, with the goal of routinely testing therapies in these models.
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Affiliation(s)
- Valtteri Syvänen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jari Koistinaho
- Neuroscience Center, Helsinki Institute of Life Science, and Drug Research Program, Division of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
| | - Šárka Lehtonen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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8
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Ameroso D, Rios M. Synaptic plasticity and the role of astrocytes in central metabolic circuits. WIREs Mech Dis 2024; 16:e1632. [PMID: 37833830 PMCID: PMC10842964 DOI: 10.1002/wsbm.1632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 09/08/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023]
Abstract
Neural circuits in the brain, primarily in the hypothalamus, are paramount to the homeostatic control of feeding and energy utilization. They integrate hunger, satiety, and body adiposity cues from the periphery and mediate the appropriate behavioral and physiological responses to satisfy the energy demands of the animal. Notably, perturbations in central homeostatic circuits have been linked to the etiology of excessive feeding and obesity. Considering the ever-changing energy requirements of the animal and required adaptations, it is not surprising that brain-feeding circuits remain plastic in adulthood and are subject to changes in synaptic strength as a consequence of nutritional status. Indeed, synapse density, probability of presynaptic transmitter release, and postsynaptic responses in hypothalamic energy balance centers are tailored to behavioral and physiological responses required to sustain survival. Mounting evidence supports key roles of astrocytes facilitating some of this plasticity. Here we discuss these synaptic plasticity mechanisms and the emerging roles of astrocytes influencing energy and glucose balance control in health and disease. This article is categorized under: Cancer > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Dominique Ameroso
- Graduate Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA 02111
| | - Maribel Rios
- Graduate Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA 02111
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111
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9
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Neha, Wali Z, Pinky, Hattiwale SH, Jamal A, Parvez S. GLP-1/Sigma/RAGE receptors: An evolving picture of Alzheimer's disease pathology and treatment. Ageing Res Rev 2024; 93:102134. [PMID: 38008402 DOI: 10.1016/j.arr.2023.102134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/18/2023] [Accepted: 11/19/2023] [Indexed: 11/28/2023]
Abstract
According to the facts and figures 2023stated that 6.7 million Americans over the age of 65 have Alzheimer's disease (AD). The scenario of AD has reached up to the maximum, of 4.1 million individuals, 2/3rd are female patients, and approximately 1 in 9 adults over the age of 65 have dementia with AD dementia. The fact that there are now no viable treatments for AD indicates that the underlying disease mechanisms are not fully understood. The progressive neurodegenerative disease, AD is characterized by amyloid plaques and neurofibrillary tangles (NFTs) of abnormally hyperphosphorylated tau protein and senile plaques (SPs), which are brought on by the buildup of amyloid beta (Aβ). Numerous attempts have been made to produce compounds that interfere with these characteristics because of significant research efforts into the primary pathogenic hallmark of this disorder. Here, we summarize several research that highlights interesting therapy strategies and the neuroprotective effects of GLP-1, Sigma, and, AGE-RAGE receptors in pre-clinical and clinical AD models.
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Affiliation(s)
- Neha
- Department of Toxicology, School of Chemical & Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Zitin Wali
- Department of Toxicology, School of Chemical & Life Sciences, Jamia Hamdard, New Delhi 110062, India
| | - Pinky
- Department of Toxicology, School of Chemical & Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Shaheenkousar H Hattiwale
- Department of Basic Medical Sciences, College of Medicine, Majmaah University, Al-Majmaah 11952, Saudi Arabia
| | - Azfar Jamal
- Department of Biology, College of Science Al-Zulfi, Majmaah University, Al-Majmaah 11952, Saudi Arabia; Health and Basic Science Research Centre, Majmaah University, Al-Majmaah 11952, Saudi Arabia
| | - Suhel Parvez
- Department of Toxicology, School of Chemical & Life Sciences, Jamia Hamdard, New Delhi 110062, India.
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Siddique AHH, Kale PP. Importance of glucose and its metabolism in neurodegenerative disorder, as well as the combination of multiple therapeutic strategies targeting α-synuclein and neuroprotection in the treatment of Parkinson's disease. Rev Neurol (Paris) 2023:S0035-3787(23)01066-4. [PMID: 38040547 DOI: 10.1016/j.neurol.2023.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 04/04/2023] [Accepted: 08/18/2023] [Indexed: 12/03/2023]
Abstract
According to recent findings, Phosphoglycerate Kinase 1 (pgk-1) enzyme is linked to Parkinson's disease (PD). Mutations in the PGK-1 gene lead to decreases in the pgk-1 enzyme which causes an imbalance in the levels of energy demand and supply. An increase in glycolytic adenosine triphosphate (ATP) production would help alleviate energy deficiency and sustain the acute energetic need of neurons. Neurodegeneration is caused by an imbalance or reduction in ATP levels. Recent data suggest that medications that increase glycolysis and neuroprotection can be used to treat PD. The current study focuses on treatment options for disorders associated with the pgk-1 enzyme, GLP-1, and A2A receptor which can be utilized to treat PD. A combination of metformin and terazosin, exenatide and meclizine, istradefylline and salbutamol treatments may benefit parkinsonism. The review also looked at potential target-specific new techniques that might assist in satisfying unfulfilled requirements in the treatment of PD.
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Affiliation(s)
- A H H Siddique
- Department of Pharmacology, SVKM's Dr Bhanuben Nanavati College of Pharmacy, V. L. Mehta Road, Vile Parle west, 400056 Mumbai, India.
| | - P P Kale
- Department of Pharmacology, SVKM's Dr Bhanuben Nanavati College of Pharmacy, V. L. Mehta Road, Vile Parle west, 400056 Mumbai, India.
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11
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Hanssen R, Rigoux L, Kuzmanovic B, Iglesias S, Kretschmer AC, Schlamann M, Albus K, Edwin Thanarajah S, Sitnikow T, Melzer C, Cornely OA, Brüning JC, Tittgemeyer M. Liraglutide restores impaired associative learning in individuals with obesity. Nat Metab 2023; 5:1352-1363. [PMID: 37592007 PMCID: PMC10447249 DOI: 10.1038/s42255-023-00859-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 07/07/2023] [Indexed: 08/19/2023]
Abstract
Survival under selective pressure is driven by the ability of our brain to use sensory information to our advantage to control physiological needs. To that end, neural circuits receive and integrate external environmental cues and internal metabolic signals to form learned sensory associations, consequently motivating and adapting our behaviour. The dopaminergic midbrain plays a crucial role in learning adaptive behaviour and is particularly sensitive to peripheral metabolic signals, including intestinal peptides, such as glucagon-like peptide 1 (GLP-1). In a single-blinded, randomized, controlled, crossover basic human functional magnetic resonance imaging study relying on a computational model of the adaptive learning process underlying behavioural responses, we show that adaptive learning is reduced when metabolic sensing is impaired in obesity, as indexed by reduced insulin sensitivity (participants: N = 30 with normal insulin sensitivity; N = 24 with impaired insulin sensitivity). Treatment with the GLP-1 receptor agonist liraglutide normalizes impaired learning of sensory associations in men and women with obesity. Collectively, our findings reveal that GLP-1 receptor activation modulates associative learning in people with obesity via its central effects within the mesoaccumbens pathway. These findings provide evidence for how metabolic signals can act as neuromodulators to adapt our behaviour to our body's internal state and how GLP-1 receptor agonists work in clinics.
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Affiliation(s)
- Ruth Hanssen
- Max Planck Institute for Metabolism Research, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Policlinic for Endocrinology, Diabetology and Preventive Medicine (PEPD), University of Cologne, Cologne, Germany
| | - Lionel Rigoux
- Max Planck Institute for Metabolism Research, Cologne, Germany
| | | | - Sandra Iglesias
- Translational Neuromodeling Unit, Institute for Biomedical Engineering, University of Zurich and Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Alina C Kretschmer
- Faculty of Medicine and University Hospital Cologne, Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD) and Excellence Center for Medical Mycology (ECMM), University of Cologne, Cologne, Germany
| | - Marc Schlamann
- Faculty of Medicine and University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Kerstin Albus
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Sharmili Edwin Thanarajah
- Max Planck Institute for Metabolism Research, Cologne, Germany
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Tamara Sitnikow
- Faculty of Medicine and University Hospital Cologne, Policlinic for Endocrinology, Diabetology and Preventive Medicine (PEPD), University of Cologne, Cologne, Germany
| | - Corina Melzer
- Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Oliver A Cornely
- Faculty of Medicine and University Hospital Cologne, Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD) and Excellence Center for Medical Mycology (ECMM), University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Clinical Trials Centre Cologne (ZKS Köln), University of Cologne, Cologne, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Policlinic for Endocrinology, Diabetology and Preventive Medicine (PEPD), University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Marc Tittgemeyer
- Max Planck Institute for Metabolism Research, Cologne, Germany.
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
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12
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Aranäs C, Edvardsson CE, Shevchouk OT, Zhang Q, Witley S, Blid Sköldheden S, Zentveld L, Vallöf D, Tufvesson-Alm M, Jerlhag E. Semaglutide reduces alcohol intake and relapse-like drinking in male and female rats. EBioMedicine 2023; 93:104642. [PMID: 37295046 PMCID: PMC10363436 DOI: 10.1016/j.ebiom.2023.104642] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/17/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND Glucagon-like peptide1 receptor (GLP-1R) agonists have been found to reduce alcohol drinking in rodents and overweight patients with alcohol use disorder (AUD). However, the probability of low semaglutide doses, an agonist with higher potency and affinity for GLP-1R, to attenuate alcohol-related responses in rodents and the underlying neuronal mechanisms is unknown. METHODS In the intermittent access model, we examined the ability of semaglutide to decrease alcohol intake and block relapse-like drinking, as well as imaging the binding of fluorescently marked semaglutide to nucleus accumbens (NAc) in both male and female rats. The suppressive effect of semaglutide on alcohol-induced locomotor stimulation and in vivo dopamine release in NAc was tested in male mice. We evaluated effect of semaglutide on the in vivo release of dopamine metabolites (DOPAC and HVA) and gene expression of enzymes metabolising dopamine (MAOA and COMT) in male mice. FINDINGS In male and female rats, acute and repeated semaglutide administration reduced alcohol intake and prevented relapse-like drinking. Moreover, fluorescently labelled semaglutide was detected in NAc of alcohol-drinking male and female rats. Further, semaglutide attenuated the ability of alcohol to cause hyperlocomotion and to elevate dopamine in NAc in male mice. As further shown in male mice, semaglutide enhanced DOPAC and HVA in NAc when alcohol was onboard and increased the gene expression of COMT and MAOA. INTERPRETATION Altogether, this indicates that semaglutide reduces alcohol drinking behaviours, possibly via a reduction in alcohol-induced reward and NAc dependent mechanisms. As semaglutide also decreased body weight of alcohol-drinking rats of both sexes, upcoming clinical studies should test the plausibility that semaglutide reduces alcohol intake and body weight in overweight AUD patients. FUNDING Swedish Research Council (2019-01676), LUA/ALF (723941) from the Sahlgrenska University Hospital and the Swedish brain foundation.
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Affiliation(s)
- Cajsa Aranäs
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Christian E Edvardsson
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Olesya T Shevchouk
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Qian Zhang
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Sarah Witley
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Sebastian Blid Sköldheden
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Lindsay Zentveld
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Maximilian Tufvesson-Alm
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
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13
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Clyburn C, Carson KE, Smith CR, Travagli RA, Browning KN. Brainstem astrocytes control homeostatic regulation of caloric intake. J Physiol 2023; 601:801-829. [PMID: 36696965 PMCID: PMC10026361 DOI: 10.1113/jp283566] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/08/2022] [Indexed: 01/27/2023] Open
Abstract
Prolonged high-fat diet (HFD) exposure is associated with hyperphagia, excess caloric intake and weight gain. After initial exposure to a HFD, a brief (24-48 h) period of hyperphagia is followed by the regulation of caloric intake and restoration of energy balance within an acute (3-5 day) period. Previous studies have demonstrated this occurs via a vagally mediated signalling cascade that increases glutamatergic transmission via activation of NMDA receptors located on gastric-projecting neurons of the dorsal motor nucleus of the vagus (DMV). The present study used electrophysiological recordings from thin brainstem slice preparations, in vivo recordings of gastric motility and tone, measurement of gastric emptying rates, and food intake studies to investigate the hypothesis that activation of brainstem astrocytes in response to acute HFD exposure is responsible for the increased glutamatergic drive to DMV neurons and the restoration of caloric balance. Pharmacological and chemogenetic inhibition of brainstem astrocytes reduced glutamatergic signalling and DMV excitability, dysregulated gastric tone and motility, attenuated the homeostatic delay in gastric emptying, and prevented the decrease in food intake that is observed during the period of energy regulation following initial exposure to HFD. Understanding the mechanisms involved in caloric regulation may provide critical insights into energy balance as well as into the hyperphagia that develops as these mechanisms are overcome. KEY POINTS: Initial exposure to a high fat diet is associated with a brief period of hyperphagia before caloric intake and energy balance is restored. This period of homeostatic regulation is associated with a vagally mediated signalling cascade that increases glutamatergic transmission to dorsal motor nucleus of the vagus (DMV) neurons via activation of synaptic NMDA receptors. The present study demonstrates that pharmacological and chemogenetic inhibition of brainstem astrocytes reduced glutamatergic signalling and DMV neuronal excitability, dysregulated gastric motility and tone and emptying, and prevented the regulation of food intake following high-fat diet exposure. Astrocyte regulation of glutamatergic transmission to DMV neurons appears to involve release of the gliotransmitters glutamate and ATP. Understanding the mechanisms involved in caloric regulation may provide critical insights into energy balance as well as into the hyperphagia that develops as these mechanisms are overcome.
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Affiliation(s)
- Courtney Clyburn
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA
- Current position: Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97056
| | - Kaitlin E. Carson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA
| | - Caleb R. Smith
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA
| | - R. Alberto Travagli
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA
- Current position: Neurobiology Research, Newport, NC 28570
| | - Kirsteen N. Browning
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA
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14
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Ellis RJ, Fan Y, Grelotti D, Tang B, Letendre S, He JJ. Astrocyte Activation is A Potential Mechanism Underlying Depressed Mood and Apathy in People with HIV. JOURNAL OF NEUROLOGY AND PSYCHOLOGY 2022; 9:05. [PMID: 37205974 PMCID: PMC10194432 DOI: 10.13188/2332-3469.1000048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Background Astrocytes become activated with certain infections, and this might alter the brain to trigger or worsen depressed mood. Indeed, astrocytes are chronically activated in people with HIV infection (PWH), who are much more frequently depressed than people without HIV (PWoH). A particularly disabling component of depression in PWH is apathy, a loss of interest, motivation, emotion, and goal-directed behavior. We tested the hypothesis that depression and apathy in PWH would be associated with higher levels of a biomarker of astrocyte activation, glial fibrillary acidic protein (GFAP), in cerebrospinal fluid (CSF). Methods We evaluated PWH in a prospective observational study using the Beck Depression Inventory-II (BDI-II) and additional standardized assessments, including lumbar puncture. We measured GFAP in CSF with a customized direct sandwich ELISA method. Data were analyzed using ANOVA and multivariable regression. Results Participants were 212 PWH, mean (SD) age 40.9±9.14 years, median (IQR) nadir and current CD4 199 (57, 326) and 411 (259, 579), 65.1% on ART, 67.3% virally suppressed. Higher CSF GFAP correlated with worse total BDI-II total scores (Pearson correlation r=0.158, p-value=0.0211), and with worse apathy scores (r=0.205, p=0.0027). The correlation between apathy/depression and GFAP was not in fluenced by other factors such as age or HIV suppression status. Conclusions Astrocyte activation, reflected in higher levels of CSF GFAP, was associated with worse depression and apathy in PWH. Interventions to reduce astrocyte activation -- for example, using a peptide-1 receptor (GLP-1R) agonist -- might be studied to evaluate their impact on disabling depression in PWH.
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Affiliation(s)
- Ronald J. Ellis
- Departments of Neurosciences and Psychiatry, University of California, San Diego, CA, United States
| | - Yan Fan
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas TX, United States
| | - David Grelotti
- Department of Psychiatry, University of California, San Diego, CA, United States
| | - Bin Tang
- Department of Psychiatry, University of California, San Diego, CA, United States
| | - Scott Letendre
- Departments of Medicine and Psychiatry, University of California, San Diego, CA, United States
| | - Johnny J. He
- Department of Microbiology and Immunology, Chicago Medical School Rosalind Franklin University, North Chicago, IL, United States
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15
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He G, Chen T, Huang L, Zhang Y, Feng Y, Qu S, Yin X, Liang L, Yan J, Liu W. Tremella fuciformis polysaccharide reduces obesity in high-fat diet-fed mice by modulation of gut microbiota. Front Microbiol 2022; 13:1073350. [PMID: 36545204 PMCID: PMC9760882 DOI: 10.3389/fmicb.2022.1073350] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Obesity is a metabolic disease associated with gut microbiota and low-grade chronic inflammation. Tremella fuciformis is a medicinal and edible fungus; polysaccharide (TP) is the main active component, which has a variety of biological activities, such as hypoglycemic and hypolipidemic. However, the anti-obesity effects and potential mechanisms of TP have never been reported. This study was conducted to elucidate the inhibitory effect of TP on high-fat diet (HFD)-induced obesity in mice. Mice were split into five groups: normal chow diet (NCD) group, NCD_TP_H group, HFD group, HFD_TP_L group and HFD_TP_H group. Our study showed that TP inhibited high-fat diet-induced weight gain and fat accumulation in mice and reduced blood glucose, hyperlipidemia and inflammation. TP also improved gut microbiota disorders by reducing the Firmicutes/Bacteroidetes ratio and modulating the relative abundance of specific gut microbiota. We also found that the anti-obesity and gut microbiota-modulating effects of TP could be transferred to HFD-fed mice via faecal microbiota transplantation (FMT), confirming that the gut microbiota was one of the targets of TP for obesity inhibition. Further studies showed that TP increased the production of short-chain fatty acids and the secretion of intestinal hormones. Our studies showed that TP inhibited obesity by modulating inflammation and the microbe-gut-brain axis, providing a rationale for developing TP to treat obesity and its complications.
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16
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Kopp KO, Glotfelty EJ, Li Y, Greig NH. Glucagon-like peptide-1 (GLP-1) receptor agonists and neuroinflammation: Implications for neurodegenerative disease treatment. Pharmacol Res 2022; 186:106550. [PMID: 36372278 PMCID: PMC9712272 DOI: 10.1016/j.phrs.2022.106550] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/03/2022] [Accepted: 11/06/2022] [Indexed: 11/13/2022]
Abstract
Chronic, excessive neuroinflammation is a key feature of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, neuroinflammatory pathways have yet to be effectively targeted in clinical treatments for such diseases. Interestingly, increased inflammation and neurodegenerative disease risk have been associated with type 2 diabetes mellitus (T2DM) and insulin resistance (IR), suggesting that treatments that mitigate T2DM pathology may be successful in treating neuroinflammatory and neurodegenerative pathology as well. Glucagon-like peptide-1 (GLP-1) is an incretin hormone that promotes healthy insulin signaling, regulates blood sugar levels, and suppresses appetite. Consequently, numerous GLP-1 receptor (GLP-1R) stimulating drugs have been developed and approved by the US Food and Drug Administration (FDA) and related global regulatory authorities for the treatment of T2DM. Furthermore, GLP-1R stimulating drugs have been associated with anti-inflammatory, neurotrophic, and neuroprotective properties in neurodegenerative disorder preclinical models, and hence hold promise for repurposing as a treatment for neurodegenerative diseases. In this review, we discuss incretin signaling, neuroinflammatory pathways, and the intersections between neuroinflammation, brain IR, and neurodegenerative diseases, with a focus on AD and PD. We additionally overview current FDA-approved incretin receptor stimulating drugs and agents in development, including unimolecular single, dual, and triple receptor agonists, and highlight those in clinical trials for neurodegenerative disease treatment. We propose that repurposing already-approved GLP-1R agonists for the treatment of neurodegenerative diseases may be a safe, efficacious, and cost-effective strategy for ameliorating AD and PD pathology by quelling neuroinflammation.
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Affiliation(s)
- Katherine O Kopp
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States.
| | - Elliot J Glotfelty
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States; Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Yazhou Li
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States
| | - Nigel H Greig
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States.
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17
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Psilopanagioti A, Nikou S, Logotheti S, Arbi M, Chartoumpekis DV, Papadaki H. Glucagon-like Peptide-1 Receptor in the Human Hypothalamus Is Associated with Body Mass Index and Colocalizes with the Anorexigenic Neuropeptide Nucleobindin-2/Nesfatin-1. Int J Mol Sci 2022; 23:ijms232314899. [PMID: 36499229 PMCID: PMC9740138 DOI: 10.3390/ijms232314899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/20/2022] [Accepted: 11/25/2022] [Indexed: 11/30/2022] Open
Abstract
Data on animals emphasize the importance of the neuronal glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) for feeding suppression, although it is unclear whether astrocytes participate in the transduction of anorectic GLP-1R-dependent signals. In humans, the brain circuitry underlying these effects remains insufficiently investigated. The present study aimed to explore GLP-1R protein expression in the human hypothalamus and its correlation with body mass index (BMI). Sections of hypothalamus from 28 autopsy cases, 11 with normal weight (BMI < 25 kg/m2) and 17 with non-normal weight (BMI ≥ 25 kg/m2), were examined using immunohistochemistry and double immunofluorescence labeling. Prominent GLP-1R immunoexpression was detected in neurons of several hypothalamic nuclei, including paraventricular, supraoptic, and infundibular nuclei; the lateral hypothalamic area (LH); and basal forebrain nuclei. Interestingly, in the LH, GLP-1R was significantly decreased in individuals with BMI ≥ 25 kg/m2 compared with their normal weight counterparts (p = 0.03). Furthermore, GLP-1R was negatively correlated (τb = −0.347, p = 0.024) with BMI levels only in the LH. GLP-1R extensively colocalized with the anorexigenic and antiobesogenic neuropeptide nucleobindin-2/nesfatin-1 but not with the astrocytic marker glial fibrillary acidic protein. These data suggest a potential role for GLP-1R in the regulation of energy balance in the human hypothalamus. In the LH, an appetite- and reward-related brain region, reduced GLP-1R immunoexpression may contribute to the dysregulation of homeostatic and/or hedonic feeding behavior. Possible effects of NUCB2/nesfatin-1 on central GLP-1R signaling require further investigation.
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Affiliation(s)
- Aristea Psilopanagioti
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, 26504 Patras, Greece
- Correspondence:
| | - Sofia Nikou
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Souzana Logotheti
- Department of Pathology, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Marina Arbi
- Department of Biology, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Dionysios V. Chartoumpekis
- Service of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Helen Papadaki
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, 26504 Patras, Greece
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18
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Bailey J, Coucha M, Bolduc DR, Burnett FN, Barrett AC, Ghaly M, Abdelsaid M. GLP-1 receptor nitration contributes to loss of brain pericyte function in a mouse model of diabetes. Diabetologia 2022; 65:1541-1554. [PMID: 35687178 DOI: 10.1007/s00125-022-05730-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 03/17/2022] [Indexed: 12/21/2022]
Abstract
AIMS/HYPOTHESIS We have previously shown that diabetes causes pericyte dysfunction, leading to loss of vascular integrity and vascular cognitive impairment and dementia (VCID). Glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1 RAs), used in managing type 2 diabetes mellitus, improve the cognitive function of diabetic individuals beyond glycaemic control, yet the mechanism is not fully understood. In the present study, we hypothesise that GLP-1 RAs improve VCID by preventing diabetes-induced pericyte dysfunction. METHODS Mice with streptozotocin-induced diabetes and non-diabetic control mice received either saline (NaCl 154 mmol/l) or exendin-4, a GLP-1 RA, through an osmotic pump over 28 days. Vascular integrity was assessed by measuring cerebrovascular neovascularisation indices (vascular density, tortuosity and branching density). Cognitive function was evaluated with Barnes maze and Morris water maze. Human brain microvascular pericytes (HBMPCs), were grown in high glucose (25 mmol/l) and sodium palmitate (200 μmol/l) to mimic diabetic conditions. HBMPCs were treated with/without exendin-4 and assessed for nitrative and oxidative stress, and angiogenic and blood-brain barrier functions. RESULTS Diabetic mice treated with exendin-4 showed a significant reduction in all cerebral pathological neovascularisation indices and an improved blood-brain barrier (p<0.05). The vascular protective effects were accompanied by significant improvement in the learning and memory functions of diabetic mice compared with control mice (p<0.05). Our results showed that HBMPCs expressed the GLP-1 receptor. Diabetes increased GLP-1 receptor expression and receptor nitration in HBMPCs. Stimulation of HBMPCs with exendin-4 under diabetic conditions decreased diabetes-induced vascular inflammation and oxidative stress, and restored pericyte function (p<0.05). CONCLUSIONS/INTERPRETATION This study provides novel evidence that brain pericytes express the GLP-1 receptor, which is nitrated under diabetic conditions. GLP-1 receptor activation improves brain pericyte function resulting in restoration of vascular integrity and BBB functions in diabetes. Furthermore, the GLP-1 RA exendin-4 alleviates diabetes-induced cognitive impairment in mice. Restoration of pericyte function in diabetes represents a novel therapeutic target for diabetes-induced cerebrovascular microangiopathy and VCID.
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Affiliation(s)
- Joseph Bailey
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA
| | - Maha Coucha
- Department of Pharmaceutical Sciences, School of Pharmacy, South University, Savannah, GA, USA
| | - Deanna R Bolduc
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA
| | - Faith N Burnett
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA
| | - Amy C Barrett
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA
| | - Mark Ghaly
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA
| | - Mohammed Abdelsaid
- Department of Biomedical Sciences, School of Medicine, Mercer University, Savannah, GA, USA.
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19
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Anti-Inflammatory Effects of GLP-1 Receptor Activation in the Brain in Neurodegenerative Diseases. Int J Mol Sci 2022; 23:ijms23179583. [PMID: 36076972 PMCID: PMC9455625 DOI: 10.3390/ijms23179583] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/17/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
The glucagon-like peptide-1 (GLP-1) is a pleiotropic hormone well known for its incretin effect in the glucose-dependent stimulation of insulin secretion. However, GLP-1 is also produced in the brain and displays a critical role in neuroprotection and inflammation by activating the GLP-1 receptor signaling pathways. Several studies in vivo and in vitro using preclinical models of neurodegenerative diseases show that GLP-1R activation has anti-inflammatory properties. This review explores the molecular mechanistic action of GLP-1 RAS in relation to inflammation in the brain. These findings update our knowledge of the potential benefits of GLP-1RAS actions in reducing the inflammatory response. These molecules emerge as a potential therapeutic tool in treating neurodegenerative diseases and neuroinflammatory pathologies.
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20
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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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21
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Smith C, Patterson-Cross R, Woodward O, Lewis J, Chiarugi D, Merkle F, Gribble F, Reimann F, Adriaenssens A. A comparative transcriptomic analysis of glucagon-like peptide-1 receptor- and glucose-dependent insulinotropic polypeptide receptor-expressing cells in the hypothalamus. Appetite 2022; 174:106022. [PMID: 35430298 PMCID: PMC7614381 DOI: 10.1016/j.appet.2022.106022] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/21/2022] [Accepted: 03/26/2022] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The hypothalamus is a key region of the brain implicated in homeostatic regulation, and is an integral centre for the control of feeding behaviour. Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretin hormones with potent glucoregulatory function through engagement of their respective cognate receptors, GLP-1R and GIPR. Recent evidence indicates that there is a synergistic effect of combining GIP- and GLP-1-based pharmacology on appetite and body weight. The mechanisms underlying the enhanced weight loss exhibited by GIPR/GLP-1R co-agonism are unknown. Gipr and Glp1r are expressed in the hypothalamus in both rodents and humans. To better understand incretin receptor-expressing cell populations, we compared the cell types and expression profiles of Gipr- and Glp1r-expressing hypothalamic cells using single-cell RNA sequencing. METHODS Using Glp1r-Cre or Gipr-Cre transgenic mouse lines, fluorescent reporters were introduced into either Glp1r- or Gipr-expressing cells, respectively, upon crossing with a ROSA26-EYFP reporter strain. From the hypothalami of these mice, fluorescent Glp1rEYFP+ or GiprEYFP+ cells were FACS-purified and sequenced using single-cell RNA sequencing. Transcriptomic analysis provided a survey of both non-neuronal and neuronal cells, and comparisons between Glp1rEYFP+ and GiprEYFP + populations were made. RESULTS A total of 14,091 Glp1rEYFP+ and GiprEYFP+ cells were isolated, sequenced and taken forward for bioinformatic analysis. Both Glp1rEYFP+ and GiprEYFP+ hypothalamic populations were transcriptomically highly heterogeneous, representing vascular cell types, oligodendrocytes, astrocytes, microglia, and neurons. The majority of GiprEYFP+ cells were non-neuronal, whereas the Glp1rEYFP+ population was evenly split between neuronal and non-neuronal cell types. Both Glp1rEYFP+ and GiprEYFP+ oligodendrocytes express markers for mature, myelin-forming oligodendrocytes. While mural cells are represented in both Glp1rEYFP+ and GiprEYFP+ populations, Glp1rEYFP+ mural cells are largely smooth muscle cells, while the majority of GiprEYFP+ mural cells are pericytes. The co-expression of regional markers indicate that clusters of Glp1rEYFP+ and GiprEYFP+ neurons have been isolated from the arcuate, ventromedial, lateral, tuberal, suprachiasmatic, and premammillary nuclei of the hypothalamus. CONCLUSIONS We have provided a detailed comparison of Glp1r and Gipr cells of the hypothalamus with single-cell resolution. This resource will provide mechanistic insight into how engaging Gipr- and Glp1r-expressing cells of the hypothalamus may result in changes in feeding behaviour and energy balance.
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Affiliation(s)
- Christopher Smith
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Ryan Patterson-Cross
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Orla Woodward
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Jo Lewis
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Davide Chiarugi
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK; Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Florian Merkle
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Fiona Gribble
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Frank Reimann
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
| | - Alice Adriaenssens
- Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
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22
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GLP-1 Receptor Agonists in Neurodegeneration: Neurovascular Unit in the Spotlight. Cells 2022; 11:cells11132023. [PMID: 35805109 PMCID: PMC9265397 DOI: 10.3390/cells11132023] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 06/21/2022] [Accepted: 06/23/2022] [Indexed: 02/07/2023] Open
Abstract
Defects in brain energy metabolism and proteopathic stress are implicated in age-related degenerative neuronopathies, exemplified by Alzheimer’s disease (AD) and Parkinson’s disease (PD). As the currently available drug regimens largely aim to mitigate cognitive decline and/or motor symptoms, there is a dire need for mechanism-based therapies that can be used to improve neuronal function and potentially slow down the underlying disease processes. In this context, a new class of pharmacological agents that achieve improved glycaemic control via the glucagon-like peptide 1 (GLP-1) receptor has attracted significant attention as putative neuroprotective agents. The experimental evidence supporting their potential therapeutic value, mainly derived from cellular and animal models of AD and PD, has been discussed in several research reports and review opinions recently. In this review article, we discuss the pathological relevance of derangements in the neurovascular unit and the significance of neuron–glia metabolic coupling in AD and PD. With this context, we also discuss some unresolved questions with regard to the potential benefits of GLP-1 agonists on the neurovascular unit (NVU), and provide examples of novel experimental paradigms that could be useful in improving our understanding regarding the neuroprotective mode of action associated with these agents.
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23
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Nikkar R, Esmaeili-Bandboni A, Badrikoohi M, Babaei P. Effects of inhibiting astrocytes and BET/BRD4 chromatin reader on spatial memory and synaptic proteins in rats with Alzheimer's disease. Metab Brain Dis 2022; 37:1119-1131. [PMID: 35244824 DOI: 10.1007/s11011-022-00940-7] [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: 12/06/2021] [Accepted: 02/21/2022] [Indexed: 10/18/2022]
Abstract
Communication between astrocytes and neurons has a profound effect on the pathophysiology of Alzheimer's disease (AD). Astrocytes regulate homeostasis and increase synaptic plasticity in physiological situations, however, they become activated during the progression of AD. Whether or not these reactions are supportive or detrimental for the central nervous system have not been understood yet. Considering epigenetic regulation of neuroinflammatory genes by chromatin readers, particularly bromodomain and extraterminal domain (BET) family, here we examined the effect of chronic co-inhibition of astrocytes metabolism (with fluorocitrate) and also BRD4 (with JQ1) on cognition deficit at early stages of AD. Forty adult male Wistar rats underwent stereotaxic cannulation for inducing AD by intrahippocampal injection of Aβ1-42 (4 μg/8 μl/rat). Then animals were divided into five groups of Saline+DMSO, Aβ + saline+DMSO, Aβ + JQ1, Aβ + FC (fluorocitrate), and Aβ + JQ1 + FC and received the related treatments. Two weeks later, spatial memory was recorded by Morris Water Maze (MWM), and the levels of phosphorylated cyclic-AMP response element binding protein (CREB), postsynaptic density 95 (PSD95), synaptophysin (SYP), and tumor necrosis factor-alpha (TNF-α) were measured in the hippocampus by western blotting and RT-qPCR. Administration of JQ1 significantly improved both acquisition and retrieval of spatial memory, which were evident by decreased escape latency and increased total time spent (TTS) in target quadrant, and significant rise in p-CREB, PSD95, and synaptophysin compared with Aβ + saline+DMSO group. In contrast, both groups receiving FC demonstrated memory decline, and reduction in p-CREB, PSD95 and synaptophysin in parallel with increase in TNF-α. Our data indicate that chronic inhibition of BRD4 significantly restores memory impaired by amyloid β partly via CREB signaling and upregulating synaptic proteins of PSD95 and synaptophysin. However, inhibition of astrocytes nullifies the memory-boosting effects of JQ1 and reduces CREB/PSD95/synaptophysin levels in hippocampus.
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Affiliation(s)
- Rastin Nikkar
- Cellular &Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Aghil Esmaeili-Bandboni
- Department of Medical Genetics, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Medical Biotechnology Research Center, School of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Mahshid Badrikoohi
- Cellular &Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Parvin Babaei
- Cellular &Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
- Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
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24
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Rosenbaum JL, Melhorn SJ, Schoen S, Webb MF, De Leon MRB, Humphreys M, Utzschneider KM, Schur EA. Evidence That Hypothalamic Gliosis Is Related to Impaired Glucose Homeostasis in Adults With Obesity. Diabetes Care 2022; 45:416-424. [PMID: 34848489 PMCID: PMC8914420 DOI: 10.2337/dc21-1535] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/03/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Preclinical research implicates hypothalamic glial cell responses in the pathogenesis of obesity and type 2 diabetes (T2D). In the current study we sought to translate such findings to humans by testing whether radiologic markers of gliosis in the mediobasal hypothalamus (MBH) were greater in individuals with obesity and impaired glucose homeostasis or T2D. RESEARCH DESIGN AND METHODS Using cross-sectional and prospective cohort study designs, we applied a validated quantitative MRI approach to assess gliosis in 67 adults with obesity and normal glucose tolerance, impaired glucose tolerance (IGT), or T2D. Assessments of glucose homeostasis were conducted via oral glucose tolerance tests (OGTT) and β-cell modeling. RESULTS We found significantly greater T2 relaxation times (a marker of gliosis by MRI), that were independent of adiposity, in the groups with IGT and T2D as compared with the group with normal glucose tolerance. Findings were present in the MBH, but not control regions. Moreover, positive linear associations were present in the MBH but not control regions between T2 relaxation time and glucose area under the curve during an OGTT, fasting glucose concentrations, hemoglobin A1c, and visceral adipose tissue mass, whereas negative linear relationships were present in the MBH for markers of insulin sensitivity and β-cell function. In a prospective cohort study, greater MBH T2 relaxation times predicted declining insulin sensitivity over 1 year. CONCLUSIONS Findings support a role for hypothalamic gliosis in the progression of insulin resistance in obesity and thus T2D pathogenesis in humans.
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Affiliation(s)
- Jennifer L Rosenbaum
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
| | - Susan J Melhorn
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Stefan Schoen
- University of Washington School of Medicine, Seattle, WA
| | - Mary F Webb
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Mary Rosalynn B De Leon
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Madelaine Humphreys
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Kristina M Utzschneider
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA.,Research and Development, Department of Veterans Affairs, Seattle, WA
| | - Ellen A Schur
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
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25
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Glial Modulation of Energy Balance: The Dorsal Vagal Complex Is No Exception. Int J Mol Sci 2022; 23:ijms23020960. [PMID: 35055143 PMCID: PMC8779587 DOI: 10.3390/ijms23020960] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 02/04/2023] Open
Abstract
The avoidance of being overweight or obese is a daily challenge for a growing number of people. The growing proportion of people suffering from a nutritional imbalance in many parts of the world exemplifies this challenge and emphasizes the need for a better understanding of the mechanisms that regulate nutritional balance. Until recently, research on the central regulation of food intake primarily focused on neuronal signaling, with little attention paid to the role of glial cells. Over the last few decades, our understanding of glial cells has changed dramatically. These cells are increasingly regarded as important neuronal partners, contributing not just to cerebral homeostasis, but also to cerebral signaling. Our understanding of the central regulation of energy balance is part of this (r)evolution. Evidence is accumulating that glial cells play a dynamic role in the modulation of energy balance. In the present review, we summarize recent data indicating that the multifaceted glial compartment of the brainstem dorsal vagal complex (DVC) should be considered in research aimed at identifying feeding-related processes operating at this level.
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26
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Beard E, Lengacher S, Dias S, Magistretti PJ, Finsterwald C. Astrocytes as Key Regulators of Brain Energy Metabolism: New Therapeutic Perspectives. Front Physiol 2022; 12:825816. [PMID: 35087428 PMCID: PMC8787066 DOI: 10.3389/fphys.2021.825816] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 12/20/2021] [Indexed: 12/11/2022] Open
Abstract
Astrocytes play key roles in the regulation of brain energy metabolism, which has a major impact on brain functions, including memory, neuroprotection, resistance to oxidative stress and homeostatic tone. Energy demands of the brain are very large, as they continuously account for 20–25% of the whole body’s energy consumption. Energy supply of the brain is tightly linked to neuronal activity, providing the origin of the signals detected by the widely used functional brain imaging techniques such as functional magnetic resonance imaging and positron emission tomography. In particular, neuroenergetic coupling is regulated by astrocytes through glutamate uptake that triggers astrocytic aerobic glycolysis and leads to glucose uptake and lactate release, a mechanism known as the Astrocyte Neuron Lactate Shuttle. Other neurotransmitters such as noradrenaline and Vasoactive Intestinal Peptide mobilize glycogen, the reserve for glucose exclusively localized in astrocytes, also resulting in lactate release. Lactate is then transferred to neurons where it is used, after conversion to pyruvate, as a rapid energy substrate, and also as a signal that modulates neuronal excitability, homeostasis, and the expression of survival and plasticity genes. Importantly, glycolysis in astrocytes and more generally cerebral glucose metabolism progressively deteriorate in aging and age-associated neurodegenerative diseases such as Alzheimer’s disease. This decreased glycolysis actually represents a common feature of several neurological pathologies. Here, we review the critical role of astrocytes in the regulation of brain energy metabolism, and how dysregulation of astrocyte-mediated metabolic pathways is involved in brain hypometabolism. Further, we summarize recent efforts at preclinical and clinical stages to target brain hypometabolism for the development of new therapeutic interventions in age-related neurodegenerative diseases.
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27
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Chen XY, Chen L, Yang W, Xie AM. GLP-1 Suppresses Feeding Behaviors and Modulates Neuronal Electrophysiological Properties in Multiple Brain Regions. Front Mol Neurosci 2022; 14:793004. [PMID: 34975402 PMCID: PMC8718614 DOI: 10.3389/fnmol.2021.793004] [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: 10/11/2021] [Accepted: 11/29/2021] [Indexed: 11/24/2022] Open
Abstract
The glucagon-like peptide-1 (GLP-1) plays important roles in the regulation of food intake and energy metabolism. Peripheral or central GLP-1 suppresses food intake and reduces body weight. The electrophysiological properties of neurons in the mammalian central nervous system reflect the neuronal excitability and the functional organization of the brain. Recent studies focus on elucidating GLP-1-induced suppression of feeding behaviors and modulation of neuronal electrophysiological properties in several brain regions. Here, we summarize that activation of GLP-1 receptor (GLP-1R) suppresses food intake and induces postsynaptic depolarization of membrane potential and/or presynaptic modulation of glutamatergic or GABAergic neurotransmission in brain nuclei located within the medulla oblongata, pons, mesencephalon, diencephalon, and telencephalon. This review may provide a background to guide future research about the cellular mechanisms of GLP-1-induced feeding inhibition.
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Affiliation(s)
- Xin-Yi Chen
- Department of International Medicine, Affiliated Hospital of Qingdao University, Qingdao, China.,Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Lei Chen
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Wu Yang
- Department of International Medicine, Affiliated Hospital of Qingdao University, Qingdao, China
| | - An-Mu Xie
- Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
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28
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A novel approach to treating opioid use disorders: Dual agonists of glucagon-like peptide-1 receptors and neuropeptide Y 2 receptors. Neurosci Biobehav Rev 2021; 131:1169-1179. [PMID: 34715149 DOI: 10.1016/j.neubiorev.2021.10.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 12/15/2022]
Abstract
The widespread misuse of opioids and opioid use disorder (OUD) together constitute a major public health crisis in the United States. The greatest challenge for successfully treating OUD is preventing relapse. Unfortunately, there are few FDA-approved medications to treat OUD and, while effective, these pharmacotherapies are limited by high relapse rates. Thus, there is a critical need for conceptually new approaches to developing novel medications to treat OUD. Here, we review an emerging preclinical literature that suggests that glucagon-like peptide-1 receptor (GLP-1R) agonists could be re-purposed for treating OUD. Potential limitations of this approach are also discussed along with an alternative strategy that involves simultaneously targeting and activating GLP-1Rs and neuropeptide Y2 receptors (Y2Rs) in the brain using a novel monomeric dual agonist peptide. Recent studies indicate that this combinatorial pharmacotherapy approach attenuates voluntary fentanyl taking and seeking in rats without producing adverse effects associated with GLP-1R agonist monotherapy alone. While future studies are required to comprehensively determine the behavioral effects of GLP-1R agonists and dual agonists of GLP-1Rs and Y2Rs in rodent models of OUD, these provocative preclinical findings highlight a potential new GLP-1R-based approach to preventing relapse in humans with OUD.
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29
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Drucker DJ. GLP-1 physiology informs the pharmacotherapy of obesity. Mol Metab 2021; 57:101351. [PMID: 34626851 PMCID: PMC8859548 DOI: 10.1016/j.molmet.2021.101351] [Citation(s) in RCA: 125] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/28/2021] [Accepted: 10/02/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Glucagon-like peptide-1 receptor agonists (GLP1RA) augment glucose-dependent insulin release and reduce glucagon secretion and gastric emptying, enabling their successful development for the treatment of type 2 diabetes (T2D). These agents also inhibit food intake and reduce body weight, fostering investigation of GLP1RA for the treatment of obesity. SCOPE OF REVIEW Here I discuss the physiology of Glucagon-like peptide-1 (GLP-1) action in the control of food intake in animals and humans, highlighting the importance of gut vs. brain-derived GLP-1 for the control of feeding and body weight. The widespread distribution and function of multiple GLP-1 receptor (GLP1R) populations in the central and autonomic nervous system are outlined, and the importance of pathways controlling energy expenditure in preclinical studies vs. reduction of food intake in both animals and humans is highlighted. The relative contributions of vagal afferent pathways vs. GLP1R+ populations in the central nervous system for the physiological reduction of food intake and the anorectic response to GLP1RA are compared and reviewed. Key data enabling the development of two GLP1RA for obesity therapy (liraglutide 3 mg daily and semaglutide 2.4 mg once weekly) are discussed. Finally, emerging data potentially supporting the combination of GLP-1 with additional peptide epitopes in unimolecular multi-agonists, as well as in fixed-dose combination therapies, are highlighted. MAJOR CONCLUSIONS The actions of GLP-1 to reduce food intake and body weight are highly conserved in obese animals and humans, in both adolescents and adults. The well-defined mechanisms of GLP-1 action through a single G protein-coupled receptor, together with the extensive safety database of GLP1RA in people with T2D, provide reassurance surrounding the long-term use of these agents in people with obesity and multiple co-morbidities. GLP1RA may also be effective in conditions associated with obesity, such as cardiovascular disease and non-alcoholic steatohepatitis (NASH). Progressive improvements in the efficacy of GLP1RA suggest that GLP-1-based therapies may soon rival bariatric surgery as viable options for the treatment of obesity and its complications.
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Affiliation(s)
- Daniel J Drucker
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON M5G 1X5, Canada.
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30
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Zobel EH, Ripa RS, von Scholten BJ, Rotbain Curovic V, Kjaer A, Hansen TW, Rossing P, Størling J. Effect of liraglutide on expression of inflammatory genes in type 2 diabetes. Sci Rep 2021; 11:18522. [PMID: 34535716 PMCID: PMC8448739 DOI: 10.1038/s41598-021-97967-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/01/2021] [Indexed: 12/14/2022] Open
Abstract
Anti-inflammatory effects of glucagon-like peptide 1 receptor agonist (GLP-1 RA) treatment in T2D may contribute to the cardiovascular benefits observed with GLP-1 RAs in outcome studies. We investigated if the GLP-1 RA liraglutide exerts anti-inflammatory effects through modulation of inflammatory gene expression in peripheral blood mononuclear cells (PBMCs). From 54 participants of a double-blinded trial where individuals with type 2 diabetes (T2D) were randomized to liraglutide (1.8 mg/day) or placebo for 26 weeks, a sub-study was performed in which PBMCs were extracted from fresh blood at study start and at end-of-treatment. The expression of selected inflammatory genes in PBMCs were measured by quantitative real-time polymerase chain reaction (PCR). Moreover, the expression of the GLP-1 receptor (GLP1R) was examined in a subset (n = 40) of the PBMC samples. The human monocytic cell line THP-1 was used for in vitro GLP-1 exposure experiments. The expression of tumor necrosis factor-α (TNFA) (p = 0.004) and interleukin-1β (IL1B) was downregulated (p = 0.046) in the liraglutide-treated group (n = 31), and unchanged in the placebo group (n = 21, p ≥ 0.11), with no significant differences between the two groups (p ≥ 0.67). The expression of interferon-γ (IFNG) and cluster of differentiation 163 (CD163) were upregulated in both groups (p ≤ 0.006) with no differences between groups (p ≥ 0.47). C–C Motif Chemokine Ligand 5 (CCL5) was upregulated in the liraglutide-treated group (p = 0.002) and unchanged in the placebo group (p = 0.14), with no significant difference between groups (p = 0.36). Intercellular adhesion molecule 1 (ICAM1) was unchanged in both groups (p ≥ 0.43). GLP1R expression in the PBMCs was undetectable. In vitro experiments showed no effect of GLP-1 treatment on inflammatory gene expression in THP-1 cells. GLP1R expression in THP-1 cells was not detectable. In summary, we observed a discrete modulatory effect of liraglutide on the expression of inflammatory genes in PBMCs. The lack of evidence for GLP1R expression in PBMCs and THP-1 cells suggests that possible effects of liraglutide on the PBMCs’ gene expression are most likely indirect. Further investigations are needed to establish the anti-inflammatory potential of GLP-1 RAs.
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Affiliation(s)
- Emilie H Zobel
- Steno Diabetes Center Copenhagen, Niels Steensens Vej 2, 2820, Gentofte, Denmark.
| | - Rasmus S Ripa
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Bernt J von Scholten
- Steno Diabetes Center Copenhagen, Niels Steensens Vej 2, 2820, Gentofte, Denmark.,Novo Nordisk A/S, Søborg, Denmark
| | | | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Tine W Hansen
- Steno Diabetes Center Copenhagen, Niels Steensens Vej 2, 2820, Gentofte, Denmark
| | - Peter Rossing
- Steno Diabetes Center Copenhagen, Niels Steensens Vej 2, 2820, Gentofte, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Joachim Størling
- Steno Diabetes Center Copenhagen, Niels Steensens Vej 2, 2820, Gentofte, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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31
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Cui QN, Stein LM, Fortin SM, Hayes MR. The role of glia in the physiology and pharmacology of GLP-1: Implications for obesity, diabetes, and neurodegenerative processes including glaucoma. Br J Pharmacol 2021; 179:715-726. [PMID: 34519040 PMCID: PMC8820182 DOI: 10.1111/bph.15683] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/17/2021] [Accepted: 08/27/2021] [Indexed: 11/28/2022] Open
Abstract
The medical application of glucagon-like peptide-1 receptor (GLP-1R) agonists is ever-growing in scope, highlighting the urgent need for a comprehensive understanding of the mechanisms through which GLP-1R activation impacts physiology and behavior. A new wave of research aims to elucidate the role GLP-1R signaling in glia plays in regulating energy balance, glycemic control, neuroinflammation, and oxidative stress. Once controversial, existing evidence now suggests that subsets of glia (e.g., microglia, tanycytes, and astrocytes) and infiltrating macrophages express GLP-1R. In this review, we discuss the implications of these findings, with particular focus on the utility of both clinically available and novel GLP-1R agonists for treating metabolic and neurodegenerative diseases, enhancing cognition, and combating substance abuse.
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Affiliation(s)
- Qi N Cui
- Scheie Eye Institute, University of Pennsylvania
| | - Lauren M Stein
- Department of Psychiatry Perelman School of Medicine, University of Pennsylvania
| | - Samantha M Fortin
- Department of Psychiatry Perelman School of Medicine, University of Pennsylvania
| | - Matthew R Hayes
- Department of Psychiatry Perelman School of Medicine, University of Pennsylvania
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32
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Guo M, Schwartz TD, Dunaief JL, Cui QN. Myeloid cells in retinal and brain degeneration. FEBS J 2021; 289:2337-2361. [PMID: 34478598 PMCID: PMC8891394 DOI: 10.1111/febs.16177] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/06/2021] [Accepted: 09/02/2021] [Indexed: 12/11/2022]
Abstract
Retinal inflammation underlies multiple prevalent ocular and neurological diseases. Similar inflammatory processes are observed in glaucomatous optic neuropathy, age-related macular degeneration, retinitis pigmentosa, posterior uveitis, Alzheimer's disease, and Parkinson's disease. In particular, human and animal studies have demonstrated the important role microglia/macrophages play in initiating and maintaining a pro-inflammatory environment in degenerative processes impacting vision. On the other hand, microglia have also been shown to have a protective role in multiple central nervous system diseases. Identifying the mechanisms underlying cell dysfunction and death is the first step toward developing novel therapeutics for these diseases impacting the central nervous system. In addition to reviewing recent key studies defining important mediators of retinal inflammation, with an emphasis on translational studies that bridge this research from bench to bedside, we also highlight a promising therapeutic class of medications, the glucagon-like peptide-1 receptor agonists. Finally, we propose areas where additional research is necessary to identify mechanisms that can be modulated to shift the balance from a neurotoxic to a neuroprotective retinal environment.
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Affiliation(s)
- Michelle Guo
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Turner D Schwartz
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Joshua L Dunaief
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Qi N Cui
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
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33
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Ludwig MQ, Todorov PV, Egerod KL, Olson DP, Pers TH. Single-Cell Mapping of GLP-1 and GIP Receptor Expression in the Dorsal Vagal Complex. Diabetes 2021; 70:1945-1955. [PMID: 34176785 PMCID: PMC8576419 DOI: 10.2337/dbi21-0003] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/08/2021] [Indexed: 11/13/2022]
Abstract
The dorsal vagal complex (DVC) in the hindbrain, composed of the area postrema, nucleus of the solitary tract, and dorsal motor nucleus of the vagus, plays a critical role in modulating satiety. The incretins glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) act directly in the brain to modulate feeding, and receptors for both are expressed in the DVC. Given the impressive clinical responses to pharmacologic manipulation of incretin signaling, understanding the central mechanisms by which incretins alter metabolism and energy balance is of critical importance. Here, we review recent single-cell approaches used to detect molecular signatures of GLP-1 and GIP receptor-expressing cells in the DVC. In addition, we discuss how current advancements in single-cell transcriptomics, epigenetics, spatial transcriptomics, and circuit mapping techniques have the potential to further characterize incretin receptor circuits in the hindbrain.
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Affiliation(s)
- Mette Q Ludwig
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Petar V Todorov
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Kristoffer L Egerod
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - David P Olson
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI
- Division of Pediatric Endocrinology, Department of Pediatrics, Michigan Medicine, Ann Arbor, MI
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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34
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Hernandez NS, Weir VR, Ragnini K, Merkel R, Zhang Y, Mace K, Rich MT, Pierce RC, Schmidt HD. GLP-1 receptor signaling in the laterodorsal tegmental nucleus attenuates cocaine seeking by activating GABAergic circuits that project to the VTA. Mol Psychiatry 2021; 26:4394-4408. [PMID: 33257815 PMCID: PMC8164646 DOI: 10.1038/s41380-020-00957-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/27/2020] [Accepted: 11/06/2020] [Indexed: 11/09/2022]
Abstract
An emerging preclinical literature suggests that targeting central glucagon-like peptide-1 receptors (GLP-1Rs) may represent a novel approach to treating cocaine use disorder. However, the exact neural circuits and cell types that mediate the suppressive effects of GLP-1R agonists on cocaine-seeking behavior are largely unknown. The laterodorsal tegmental nucleus (LDTg) expresses GLP-1Rs and functions as a neuroanatomical hub connecting the nucleus tractus solitarius (NTS), the primary source of central GLP-1, with midbrain and forebrain nuclei known to regulate cocaine-seeking behavior. The goal of this study was to characterize the role of LDTg GLP-1R-expressing neurons and their projections to the ventral tegmental area (VTA) in the reinstatement of cocaine-seeking behavior, an animal model of relapse. Here, we showed that administration of the GLP-1R agonist exendin-4 (Ex-4) directly into the LDTg significantly attenuated cocaine seeking at a dose that did not affect sucrose seeking, ad libitum food intake, or body weight. In addition, our studies revealed that selectively activating NTS-to-LDTg circuits attenuated cocaine seeking via a GLP-1R-dependent mechanism. We also demonstrated, for the first time, that GLP-1Rs are expressed primarily on GABAergic neurons in the LDTg and that the efficacy of Ex-4 to reduce cocaine seeking depends, in part, on activation of LDTg-to-VTA GABAergic projections. Taken together, these studies identify a central mechanism by which Ex-4 attenuates cocaine seeking and highlight GABAergic GLP-1R-expressing circuits in the midbrain as important anti-craving pathways in regulating cocaine craving-induced relapse.
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Affiliation(s)
- Nicole S. Hernandez
- Neuroscience Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Vanessa R. Weir
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104
| | - Kael Ragnini
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104
| | - Riley Merkel
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104
| | - Yafang Zhang
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104
| | - Kyla Mace
- Pharmacology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Phildelphia, PA 19104
| | - Matthew T. Rich
- Brain Health Institute and Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854
| | - R. Christopher Pierce
- Brain Health Institute and Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854
| | - Heath D. Schmidt
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104,Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104
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Williams DL. The diverse effects of brain glucagon-like peptide 1 receptors on ingestive behaviour. Br J Pharmacol 2021; 179:571-583. [PMID: 33990944 DOI: 10.1111/bph.15535] [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: 01/17/2021] [Revised: 04/12/2021] [Accepted: 05/07/2021] [Indexed: 12/31/2022] Open
Abstract
Glucagon-like peptide 1 (GLP-1) is well known as a gut hormone and also acts as a neuropeptide, produced in a discrete population of caudal brainstem neurons that project widely throughout the brain. GLP-1 receptors are expressed in many brain areas of relevance to energy balance, and stimulation of these receptors at many of these sites potently suppresses food intake. This review surveys the current evidence for effects mediated by GLP-1 receptors on feeding behaviour at a wide array of brain sites and discusses behavioural and neurophysiological mechanisms for the effects identified thus far. Taken together, it is clear that GLP-1 receptor activity in the brain can influence feeding by diverse means, including mediation of gastrointestinal satiation and/or satiety signalling, suppression of motivation for food reward, induction of nausea and mediation of restraint stress-induced hypophagia, but many questions about the organization of this system remain.
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Affiliation(s)
- Diana L Williams
- Department of Psychology, Program in Neuroscience, Florida State University, Tallahassee, Florida, USA
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Clyburn C, Browning KN. Glutamatergic plasticity within neurocircuits of the dorsal vagal complex and the regulation of gastric functions. Am J Physiol Gastrointest Liver Physiol 2021; 320:G880-G887. [PMID: 33730858 PMCID: PMC8202199 DOI: 10.1152/ajpgi.00014.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The meticulous regulation of the gastrointestinal (GI) tract is required for the coordination of gastric motility and emptying, intestinal secretion, absorption, and transit as well as for the overarching management of food intake and energy homeostasis. Disruption of GI functions is associated with the development of severe GI disorders and the alteration of food intake and caloric balance. Functional GI disorders as well as the dysregulation of energy balance and food intake are frequently associated with, or result from, alterations in the central regulation of GI control. The faithful and rapid transmission of information from the stomach and upper GI tract to second-order neurons of the nucleus of the tractus solitarius (NTS) relies on the delicate modulation of excitatory glutamatergic transmission, as does the relay of integrated signals from the NTS to parasympathetic efferent neurons of the dorsal motor nucleus of the vagus (DMV). Many studies have focused on understanding the physiological and pathophysiological modulation of these glutamatergic synapses, although their role in the control and regulation of GI functions has lagged behind that of cardiovascular and respiratory functions. The purpose of this review is to examine the current literature exploring the role of glutamatergic transmission in the DVC in the regulation of GI functions.
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Affiliation(s)
- Courtney Clyburn
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Kirsteen N. Browning
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, Pennsylvania
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Dash R, Mitra S, Ali MC, Oktaviani DF, Hannan MA, Choi SM, Moon IS. Phytosterols: Targeting Neuroinflammation in Neurodegeneration. Curr Pharm Des 2021; 27:383-401. [PMID: 32600224 DOI: 10.2174/1381612826666200628022812] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 05/02/2020] [Indexed: 11/22/2022]
Abstract
Plant-derived sterols, phytosterols, are well known for their cholesterol-lowering activity in serum and their anti-inflammatory activities. Recently, phytosterols have received considerable attention due to their beneficial effects on various non-communicable diseases, and recommended use as daily dietary components. The signaling pathways mediated in the brain by phytosterols have been evaluated, but little is known about their effects on neuroinflammation, and no clinical studies have been undertaken on phytosterols of interest. In this review, we discuss the beneficial roles of phytosterols, including their attenuating effects on inflammation, blood cholesterol levels, and hallmarks of the disease, and their regulatory effects on neuroinflammatory disease pathways. Despite recent advancements made in phytosterol pharmacology, some critical questions remain unanswered. Therefore, we have tried to highlight the potential of phytosterols as viable therapeutics against neuroinflammation and to direct future research with respect to clinical applications.
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Affiliation(s)
- Raju Dash
- Department of Anatomy, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Korea
| | - Sarmistha Mitra
- Plasma Bioscience Research Center, Plasma Bio-display, Kwangwoon University, Seoul-01897, Korea
| | - Md Chayan Ali
- Department of Biotechnology and Genetic Engineering, Islamic University, Kushtia-7003, Bangladesh
| | - Diyah Fatimah Oktaviani
- Department of Anatomy, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Korea
| | - Md Abdul Hannan
- Department of Anatomy, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Korea
| | - Sung Min Choi
- Department of Pediatrics, Dongguk University College of Medicine, Gyeongju-38066, Korea
| | - Il Soo Moon
- Department of Anatomy, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Korea
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González-García I, Gruber T, García-Cáceres C. Insulin action on astrocytes: From energy homeostasis to behaviour. J Neuroendocrinol 2021; 33:e12953. [PMID: 33724579 DOI: 10.1111/jne.12953] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/14/2022]
Abstract
Astrocytes are specialised glial cells that integrate distinct inputs arising from neurones, other glial cells and the microcirculation to regulate diverse aspects of brain function. A growing body of emerging evidence supports that astrocytes, similar to neurones, also play active roles in the neuroendocrine control of metabolism by responding to afferent nutritional and hormonal cues and translating these metabolic cues into neuronal inputs. Specifically, insulin action in astrocytes has received special emphasis given its newly discovered regulatory role in brain glucose uptake, which until recently was assumed to be an insulin independent process. We now know that insulin signalling in astrocytes regulates metabolic processes and behavioural responses through coupling brain glucose uptake with nutrient availability to maintain energy balance and systemic glucose homeostasis. Moreover, genetic ablation of the insulin receptor in astrocytes is associated with anxiety- and depressive-like behaviours, confirming that these glial cells are involved in the regulation of cognition and mood via insulin action. Here, we provide a comprehensive review of the most relevant findings that have been made over the course of the last few years linking insulin signalling in astrocytes with the pathogenesis of brain metabolic and neurodegenerative diseases; a still unexplored field, but with a high translational potential for developing therapies.
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Affiliation(s)
- Ismael González-García
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Tim Gruber
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Cristina García-Cáceres
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Medizinische Klinik and Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany
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Shi Z, Qin M, Huang L, Xu T, Chen Y, Hu Q, Peng S, Peng Z, Qu LN, Chen SG, Tuo QH, Liao DF, Wang XP, Wu RR, Yuan TF, Li YH, Liu XM. Human torpor: translating insights from nature into manned deep space expedition. Biol Rev Camb Philos Soc 2020; 96:642-672. [PMID: 33314677 DOI: 10.1111/brv.12671] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/09/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022]
Abstract
During a long-duration manned spaceflight mission, such as flying to Mars and beyond, all crew members will spend a long period in an independent spacecraft with closed-loop bioregenerative life-support systems. Saving resources and reducing medical risks, particularly in mental heath, are key technology gaps hampering human expedition into deep space. In the 1960s, several scientists proposed that an induced state of suppressed metabolism in humans, which mimics 'hibernation', could be an ideal solution to cope with many issues during spaceflight. In recent years, with the introduction of specific methods, it is becoming more feasible to induce an artificial hibernation-like state (synthetic torpor) in non-hibernating species. Natural torpor is a fascinating, yet enigmatic, physiological process in which metabolic rate (MR), body core temperature (Tb ) and behavioural activity are reduced to save energy during harsh seasonal conditions. It employs a complex central neural network to orchestrate a homeostatic state of hypometabolism, hypothermia and hypoactivity in response to environmental challenges. The anatomical and functional connections within the central nervous system (CNS) lie at the heart of controlling synthetic torpor. Although progress has been made, the precise mechanisms underlying the active regulation of the torpor-arousal transition, and their profound influence on neural function and behaviour, which are critical concerns for safe and reversible human torpor, remain poorly understood. In this review, we place particular emphasis on elaborating the central nervous mechanism orchestrating the torpor-arousal transition in both non-flying hibernating mammals and non-hibernating species, and aim to provide translational insights into long-duration manned spaceflight. In addition, identifying difficulties and challenges ahead will underscore important concerns in engineering synthetic torpor in humans. We believe that synthetic torpor may not be the only option for manned long-duration spaceflight, but it is the most achievable solution in the foreseeable future. Translating the available knowledge from natural torpor research will not only benefit manned spaceflight, but also many clinical settings attempting to manipulate energy metabolism and neurobehavioural functions.
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Affiliation(s)
- Zhe Shi
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China.,Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China.,State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China.,Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200030, China
| | - Meng Qin
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Lu Huang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, 510632, China
| | - Tao Xu
- Department of Anesthesiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Ying Chen
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Qin Hu
- College of Life Sciences and Bio-Engineering, Beijing University of Technology, Beijing, 100024, China
| | - Sha Peng
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Zhuang Peng
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Li-Na Qu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Shan-Guang Chen
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Qin-Hui Tuo
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Duan-Fang Liao
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Xiao-Ping Wang
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Ren-Rong Wu
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Ti-Fei Yuan
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200030, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226000, China
| | - Ying-Hui Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Xin-Min Liu
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China.,State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China.,Research Center for Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193, China
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40
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Smedlund KB, Hill JW. The role of non-neuronal cells in hypogonadotropic hypogonadism. Mol Cell Endocrinol 2020; 518:110996. [PMID: 32860862 DOI: 10.1016/j.mce.2020.110996] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/01/2020] [Accepted: 08/16/2020] [Indexed: 12/18/2022]
Abstract
The hypothalamic-pituitary-gonadal axis is controlled by gonadotropin-releasing hormone (GnRH) released by the hypothalamus. Disruption of this system leads to impaired reproductive maturation and function, a condition known as hypogonadotropic hypogonadism (HH). Most studies to date have focused on genetic causes of HH that impact neuronal development and function. However, variants may also impact the functioning of non-neuronal cells known as glia. Glial cells make up 50% of brain cells of humans, primates, and rodents. They include radial glial cells, microglia, astrocytes, tanycytes, oligodendrocytes, and oligodendrocyte precursor cells. Many of these cells influence the hypothalamic neuroendocrine system controlling fertility. Indeed, glia regulate GnRH neuronal activity and secretion, acting both at their cell bodies and their nerve endings. Recent work has also made clear that these interactions are an essential aspect of how the HPG axis integrates endocrine, metabolic, and environmental signals to control fertility. Recognition of the clinical importance of interactions between glia and the GnRH network may pave the way for the development of new treatment strategies for dysfunctions of puberty and adult fertility.
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Affiliation(s)
- Kathryn B Smedlund
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA
| | - Jennifer W Hill
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA.
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41
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Diz-Chaves Y, Herrera-Pérez S, González-Matías LC, Lamas JA, Mallo F. Glucagon-Like Peptide-1 (GLP-1) in the Integration of Neural and Endocrine Responses to Stress. Nutrients 2020; 12:nu12113304. [PMID: 33126672 PMCID: PMC7692797 DOI: 10.3390/nu12113304] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/14/2020] [Accepted: 10/27/2020] [Indexed: 12/20/2022] Open
Abstract
Glucagon like-peptide 1 (GLP-1) within the brain is produced by a population of preproglucagon neurons located in the caudal nucleus of the solitary tract. These neurons project to the hypothalamus and another forebrain, hindbrain, and mesolimbic brain areas control the autonomic function, feeding, and the motivation to feed or regulate the stress response and the hypothalamic-pituitary-adrenal axis. GLP-1 receptor (GLP-1R) controls both food intake and feeding behavior (hunger-driven feeding, the hedonic value of food, and food motivation). The activation of GLP-1 receptors involves second messenger pathways and ionic events in the autonomic nervous system, which are very relevant to explain the essential central actions of GLP-1 as neuromodulator coordinating food intake in response to a physiological and stress-related stimulus to maintain homeostasis. Alterations in GLP-1 signaling associated with obesity or chronic stress induce the dysregulation of eating behavior. This review summarized the experimental shreds of evidence from studies using GLP-1R agonists to describe the neural and endocrine integration of stress responses and feeding behavior.
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Affiliation(s)
- Yolanda Diz-Chaves
- CINBIO, Universidade de Vigo, Grupo FB3A, Laboratorio de Endocrinología, 36310 Vigo, Spain;
- Correspondence: (Y.D.-C.); (F.M.); Tel.: +34-(986)-130226 (Y.D.-C.); +34-(986)-812393 (F.M.)
| | - Salvador Herrera-Pérez
- CINBIO, Universidade de Vigo, Grupo FB3B, Laboratorio de Neurociencia, 36310 Vigo, Spain; (S.H.-P.); (J.A.L.)
| | | | - José Antonio Lamas
- CINBIO, Universidade de Vigo, Grupo FB3B, Laboratorio de Neurociencia, 36310 Vigo, Spain; (S.H.-P.); (J.A.L.)
| | - Federico Mallo
- CINBIO, Universidade de Vigo, Grupo FB3A, Laboratorio de Endocrinología, 36310 Vigo, Spain;
- Correspondence: (Y.D.-C.); (F.M.); Tel.: +34-(986)-130226 (Y.D.-C.); +34-(986)-812393 (F.M.)
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42
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Early life overnutrition impairs plasticity of non-neuronal brainstem cells and drives obesity in offspring across development in rats. Int J Obes (Lond) 2020; 44:2405-2418. [PMID: 32999409 DOI: 10.1038/s41366-020-00658-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 07/17/2020] [Accepted: 08/15/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND The prevalence of adolescent obesity has increased dramatically, becoming a serious public health concern. While previous evidence suggests that in utero- and early postnatal overnutrition increases adult-onset obesity risk, the neurobiological mechanisms underlying this outcome are not well understood. Non-neuronal cells play an underestimated role in the physiological responses to metabolic/nutrient signals. Hypothalamic glial-mediated inflammation is now considered a contributing factor in the development and perpetuation of obesity; however, attention on the role of gliosis and microglia activation in other nuclei is still needed. METHODS/RESULTS Here, we demonstrate that early life consumption of high-fat/sucrose diet (HFSD) is sufficient to increase offspring body weight, hyperleptinemia and potentially maladaptive cytoarchitectural changes in the brainstem dorsal-vagal-complex (DVC), an essential energy balance processing hub, across postnatal development. Our data demonstrate that pre- and postnatal consumption of HFSD result in increased body weight, hyperleptinemia and dramatically affects the non-neuronal landscape, and therefore the plasticity of the DVC in the developing offspring. CONCLUSIONS Current findings are very provocative, considering the importance of the DVC in appetite regulation, suggesting that HFSD-consumption during early life may contribute to subsequent obesity risk via DVC cytoarchitectural changes.
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López-Ferreras L, Eerola K, Shevchouk OT, Richard JE, Nilsson FH, Jansson LE, Hayes MR, Skibicka KP. The supramammillary nucleus controls anxiety-like behavior; key role of GLP-1R. Psychoneuroendocrinology 2020; 119:104720. [PMID: 32563174 DOI: 10.1016/j.psyneuen.2020.104720] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/30/2020] [Accepted: 05/18/2020] [Indexed: 01/04/2023]
Abstract
Anxiety disorders are among the most prevalent categories of mental illnesses. The gut-brain axis, along with gastrointestinally-derived neuropeptides, like glucagon-like peptide-1 (GLP-1), are emerging as potential key regulators of emotionality, including anxiety behavior. However, the neuroanatomical substrates from which GLP-1 exerts its anxiogenic effect remain poorly characterized. Here we focus on a relatively new candidate nucleus, the supramammillary nucleus (SuM), located just caudal to the lateral hypothalamus and ventral to the ventral tegmental area. Our focus on the SuM is supported by previous data showing expression of GLP-1R mRNA throughout the SuM and activation of the SuM during anxiety-inducing behaviors in rodents. Data show that chemogenetic activation of neurons in the SuM results in an anxiolytic response in male and female rats. In contrast, selective activation of SuM GLP-1R, by microinjection of a GLP-1R agonist exendin-4 into the SuM resulted in potent anxiety-like behavior, measured in both open field and elevated plus maze tests in male and female rats. This anxiogenic effect of GLP-1R activation persisted after high-fat diet exposure. Importantly, reduction of GLP-1R expression in the SuM, by AAV-shRNA GLP-1R knockdown, resulted in a clear anxiolytic response; an effect only observed in female rats. Our data identify a new neural substrate for GLP-1 control of anxiety-like behavior and indicate that the SuM GLP-1R are sufficient for anxiogenesis in both sexes, but necessary only in females.
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Affiliation(s)
- L López-Ferreras
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden
| | - K Eerola
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden; Research Centre of Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, Finland
| | - O T Shevchouk
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - J E Richard
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - F H Nilsson
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - L E Jansson
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - M R Hayes
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, USA
| | - K P Skibicka
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden; Department of Nutritional Sciences, Pennsylvania State University, University Park, PA, USA.
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Grill HJ. A Role for GLP-1 in Treating Hyperphagia and Obesity. Endocrinology 2020; 161:5855153. [PMID: 32516384 PMCID: PMC7899438 DOI: 10.1210/endocr/bqaa093] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 06/02/2020] [Accepted: 06/04/2020] [Indexed: 02/06/2023]
Abstract
Obesity is a chronic recurring disease whose prevalence has almost tripled over the past 40 years. In individuals with obesity, there is significant increased risk of morbidity and mortality, along with decreased quality of life. Increased obesity prevalence results, at least partly, from the increased global food supply that provides ubiquitous access to tasty, energy-dense foods. These hedonic foods and the nonfood cues that through association become reward predictive cues activate brain appetitive control circuits that drive hyperphagia and weight gain by enhancing food-seeking, motivation, and reward. Behavioral therapy (diet and lifestyle modifications) is the recommended initial treatment for obesity, yet it often fails to achieve meaningful weight loss. Furthermore, those who lose weight regain it over time through biological regulation. The need to effectively treat the pathophysiology of obesity thus centers on biologically based approaches such as bariatric surgery and more recently developed drug therapies. This review highlights neurobiological aspects relevant to obesity causation and treatment by emphasizing the common aspects of the feeding-inhibitory effects of multiple signals. We focus on glucagon like peptide-1 receptor (GLP-1R) signaling as a promising obesity treatment target by discussing the activation of intestinal- and brain-derived GLP-1 and GLP-1R expressing central nervous system circuits resulting from normal eating, bariatric surgery, and GLP-1R agonist drug therapy. Given the increased availability of energy-dense foods and frequent encounters with cues that drive hyperphagia, this review also describes how bariatric surgery and GLP-1R agonist therapies influence food reward and the motivational drive to overeat.
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Affiliation(s)
- Harvey J Grill
- Institute of Diabetes, Obesity and Metabolism, Graduate Groups for Psychology and Neuroscience, University of Pennsylvania, Philadelphia, PA
- Correspondence: Harvey J. Grill, Institute of Diabetes, Obesity and Metabolism, Graduate Groups fo Psychology and Neuroscience, University of Pennsylvania, Philadelphia, PA 19104. E-mail:
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Glucagon-like peptide-1 receptors and sexual behaviors in male mice. Psychoneuroendocrinology 2020; 117:104687. [PMID: 32388229 DOI: 10.1016/j.psyneuen.2020.104687] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/20/2020] [Accepted: 04/11/2020] [Indexed: 01/02/2023]
Abstract
The gut-brain peptide glucagon-like peptide-1 (GLP-1) reduces reward from palatable food and drugs of abuse. Recent rodent studies show that activation of GLP-1 receptors (GLP-1R) within the nucleus of the solitary tract (NTS) not only suppresses the motivation and intake of palatable food, but also reduces alcohol-related behaviors. As reward induced by addictive drugs and sexual behaviors involve similar neurocircuits, we hypothesized that activation of GLP-1R suppresses sexual behavior in sexually naïve male mice. We initially identified that systemic administration of the GLP-1R agonist, exendin-4 (Ex4), decreased the frequency and duration of mounting behaviors, but did not alter the preference for females or female bedding. Thereafter infusion of Ex4 into the NTS decreased various behaviors of the sexual interaction chain, namely social, mounting and self-grooming behaviors. In male mice tested in the sexual interaction test, NTS-Ex4 increased dopamine turnover and enhanced serotonin levels in the nucleus accumbens (NAc). In addition, these mice displayed higher corticosterone, but not testosterone, levels in plasma. Finally, GLP-1R antagonist, exendin-3 (9-39) amide (Ex9), infused into the NTS differentially altered the ability of systemic-Ex4 to suppress the various behaviors of the sexual interaction chain, indicating that GLP-1R within the NTS is one of many sub-regions contributing to the GLP-1 dependent sexual behavior link. In these mice NTS-Ex9 partly blocked the systemic-Ex4 enhancement of corticosterone levels. Collectively, these data highlight that activation of GLP-1R, specifically those in the NTS, reduces sexual interaction behaviors in sexually naïve male mice and further provide a link between NTS-GLP-1R activation and reward-related behaviors.
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46
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MacDonald AJ, Ellacott KLJ. Astrocytes in the nucleus of the solitary tract: Contributions to neural circuits controlling physiology. Physiol Behav 2020; 223:112982. [PMID: 32535136 PMCID: PMC7378570 DOI: 10.1016/j.physbeh.2020.112982] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 05/04/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022]
Abstract
The nucleus of the solitary tract (NTS) is the primary brainstem centre for the integration of physiological information from the periphery transmitted via the vagus nerve. In turn, the NTS feeds into downstream circuits regulating physiological parameters. Astrocytes are glial cells which have key roles in maintaining CNS tissue homeostasis and regulating neuronal communication. Recently an increasing number of studies have implicated astrocytes in the regulation of synaptic transmission and physiology. This review aims to highlight evidence for a role for astrocytes in the functions of the NTS. Astrocytes maintain and modulate NTS synaptic transmission contributing to the control of diverse physiological systems namely cardiovascular, respiratory, glucoregulatory, and gastrointestinal. In addition, it appears these cells may have a role in central control of feeding behaviour. As such these cells are a key component of signal processing and physiological control by the NTS.
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Affiliation(s)
- Alastair J MacDonald
- Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Level 4, RILD, Barrack Rd, Exeter EX2 5DW, UK
| | - Kate L J Ellacott
- Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Level 4, RILD, Barrack Rd, Exeter EX2 5DW, UK.
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47
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Timper K, Del Río-Martín A, Cremer AL, Bremser S, Alber J, Giavalisco P, Varela L, Heilinger C, Nolte H, Trifunovic A, Horvath TL, Kloppenburg P, Backes H, Brüning JC. GLP-1 Receptor Signaling in Astrocytes Regulates Fatty Acid Oxidation, Mitochondrial Integrity, and Function. Cell Metab 2020; 31:1189-1205.e13. [PMID: 32433922 PMCID: PMC7272126 DOI: 10.1016/j.cmet.2020.05.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 12/09/2019] [Accepted: 05/02/2020] [Indexed: 02/06/2023]
Abstract
Astrocytes represent central regulators of brain glucose metabolism and neuronal function. They have recently been shown to adapt their function in response to alterations in nutritional state through responding to the energy state-sensing hormones leptin and insulin. Here, we demonstrate that glucagon-like peptide (GLP)-1 inhibits glucose uptake and promotes β-oxidation in cultured astrocytes. Conversely, postnatal GLP-1 receptor (GLP-1R) deletion in glial fibrillary acidic protein (GFAP)-expressing astrocytes impairs astrocyte mitochondrial integrity and activates an integrated stress response with enhanced fibroblast growth factor (FGF)21 production and increased brain glucose uptake. Accordingly, central neutralization of FGF21 or astrocyte-specific FGF21 inactivation abrogates the improvements in glucose tolerance and learning in mice lacking GLP-1R expression in astrocytes. Collectively, these experiments reveal a role for astrocyte GLP-1R signaling in maintaining mitochondrial integrity, and lack of GLP-1R signaling mounts an adaptive stress response resulting in an improvement of systemic glucose homeostasis and memory formation.
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Affiliation(s)
- Katharina Timper
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Almudena Del Río-Martín
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Anna Lena Cremer
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany
| | - Stephan Bremser
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Zoology, Biocenter, University of Cologne, Zuelpicher Str. 47B, 50674 Cologne, Germany
| | - Jens Alber
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Patrick Giavalisco
- Max Planck Institute for Biology of Aging, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Luis Varela
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Christian Heilinger
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Hendrik Nolte
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Aleksandra Trifunovic
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, 50931 Cologne, Germany
| | - Tamas L Horvath
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Anatomy and Histology, University of Veterinary Medicine, 1078 Budapest, Hungary
| | - Peter Kloppenburg
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Zoology, Biocenter, University of Cologne, Zuelpicher Str. 47B, 50674 Cologne, Germany
| | - Heiko Backes
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; National Center for Diabetes Research (DZD), Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
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48
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Fortin SM, Chen J, Hayes MR. Hindbrain melanocortin 3/4 receptors modulate the food intake and body weight suppressive effects of the GLP-1 receptor agonist, liraglutide. Physiol Behav 2020; 220:112870. [PMID: 32179053 PMCID: PMC7227776 DOI: 10.1016/j.physbeh.2020.112870] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/14/2020] [Accepted: 03/09/2020] [Indexed: 12/19/2022]
Abstract
Simultaneously targeting multiple energy balance control systems is a promising direction for the development of obesity pharmacotherapies. Here, we explore the interaction between the GLP-1 and melanocortin system within the dorsal vagal complex (DVC) of the caudal brainstem. Using a pharmacological approach, we demonstrate that the full anorectic potential of liraglutide, an FDA-approved GLP-1 analog for the treatment of obesity, requires DVC melanocortin 3/4 receptor (MC3/4R) signaling. Specifically, the food intake and body weight suppressive effects of liraglutide were attenuated by DVC administration of the MC3/4R antagonist SHU9119. In contrast, the anorectic effects of liraglutide were enhanced by combined activation of DVC MC3/4Rs using the agonist MTII. Our findings highlight the modulation of liraglutide-induced anorexia by DVC MC3/4R signaling, thereby suggesting a site of action at which two important energy balance control systems interact.
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Affiliation(s)
- Samantha M Fortin
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States.
| | - Jack Chen
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
| | - Matthew R Hayes
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States.
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49
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Graham DL, Durai HH, Trammell TS, Noble BL, Mortlock DP, Galli A, Stanwood GD. A novel mouse model of glucagon-like peptide-1 receptor expression: A look at the brain. J Comp Neurol 2020; 528:2445-2470. [PMID: 32170734 DOI: 10.1002/cne.24905] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 03/07/2020] [Accepted: 03/10/2020] [Indexed: 12/18/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is an incretin hormone with a number of functions to maintain energy homeostasis and contribute to motivated behavior, both peripherally and within the central nervous system (CNS). These functions, which include insulin secretion, gastric emptying, satiety, and the hedonic aspects of food and drug intake, are primarily mediated through stimulation of the GLP-1 receptor. While this receptor plays an important role in a variety of physiological outcomes, data regarding its CNS expression has been primarily limited to regional receptor binding and single-label transcript expression studies. We thus developed a bacterial artificial chromosome transgenic mouse, in which expression of a red fluorescent protein (mApple) is driven by the GLP-1R promoter. Using this reporter mouse, we characterized the regional and cellular expression patterns of GLP-1R expressing cells in the CNS, using double-label immunohistochemistry and in situ hybridization. GLP-1R-expressing cells were enriched in several key brain regions and circuits, including the lateral septum, hypothalamus, amygdala, bed nucleus of the stria terminalis, hippocampus, ventral midbrain, periaqueductal gray, and cerebral cortex. In most regions, GLP-1R primarily colocalized with GABAergic neurons, except within some regions such as the hippocampus, where it was co-expressed in glutamatergic neurons. GLP-1R-mApple cells were highly co-expressed with 5-HT3 receptor-containing neurons within the cortex and striatum, as well as with dopamine receptor- and calbindin-expressing cells within the lateral septum, the brain region in which GLP-1R is most highly expressed. In this manuscript, we provide detailed images of GLP-1R-mApple expression and distribution within the brain and characterization of these neurons.
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Affiliation(s)
- Devon L Graham
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Heather H Durai
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Taylor S Trammell
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Brenda L Noble
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Douglas P Mortlock
- Vanderbilt Genetics Institute and Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Aurelio Galli
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Gregg D Stanwood
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
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50
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Dorsal vagal complex and hypothalamic glia differentially respond to leptin and energy balance dysregulation. Transl Psychiatry 2020; 10:90. [PMID: 32152264 PMCID: PMC7062837 DOI: 10.1038/s41398-020-0767-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 01/16/2023] Open
Abstract
Previous studies identify a role for hypothalamic glia in energy balance regulation; however, a narrow hypothalamic focus provides an incomplete understanding of how glia throughout the brain respond to and regulate energy homeostasis. We examined the responses of glia in the dorsal vagal complex (DVC) to the adipokine leptin and high fat diet-induced obesity. DVC astrocytes functionally express the leptin receptor; in vivo pharmacological studies suggest that DVC astrocytes partly mediate the anorectic effects of leptin in lean but not diet-induced obese rats. Ex vivo calcium imaging indicated that these changes were related to a lower proportion of leptin-responsive cells in the DVC of obese versus lean animals. Finally, we investigated DVC microglia and astroglia responses to leptin and energy balance dysregulation in vivo: obesity decreased DVC astrogliosis, whereas the absence of leptin signaling in Zucker rats was associated with extensive astrogliosis in the DVC and decreased hypothalamic micro- and astrogliosis. These data uncover a novel functional heterogeneity of astrocytes in different brain nuclei of relevance to leptin signaling and energy balance regulation.
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