1
|
Barakat GM, Ramadan W, Assi G, Khoury NBE. Satiety: a gut-brain-relationship. J Physiol Sci 2024; 74:11. [PMID: 38368346 PMCID: PMC10874559 DOI: 10.1186/s12576-024-00904-9] [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: 12/25/2023] [Accepted: 01/30/2024] [Indexed: 02/19/2024]
Abstract
Many hormones act on the hypothalamus to control hunger and satiety through various pathways closely associated with several factors. When food is present in the gastro intestinal (GI) tract, enteroendocrine cells (EECs) emit satiety signals such as cholecystokinin (CCK), glucagon like peptide-1 (GLP-1) and peptide YY (PYY), which can then communicate with the vagus nerve to control food intake. More specifically, satiety has been shown to be particularly affected by the GLP-1 hormone and its receptor agonists that have lately been acknowledged as a promising way to reduce weight. In addition, there is increasing evidence that normal flora is also involved in the peripheral, central, and reward system that impact satiety. Moreover, neurologic pathways control satiety through neurotransmitters. In this review, we discuss the different roles of each of the GLP-1 hormone and its agonist, gut microbiomes, as well as neurotransmitters and their interconnected relation in the regulation of body's satiety homeostasis.
Collapse
Affiliation(s)
- Ghinwa M Barakat
- Biological and Chemical Sciences Department, School of Arts and Sciences, Lebanese International University, Beirut, Lebanon.
| | - Wiam Ramadan
- Biological and Chemical Sciences Department, School of Arts and Sciences, Lebanese International University, Beirut, Lebanon
- Nutrition and Food Sciences Department, School of Arts and Sciences, Lebanese International University, Beirut, Lebanon
| | - Ghaith Assi
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
| | - Noura B El Khoury
- Psychology department, Faculty of Arts and Sciences, University of Balamand, Balamand, Lebanon
| |
Collapse
|
2
|
Zhuang Z, Zhou P, Wang J, Lu X, Chen Y. The Characteristics, Mechanisms and Therapeutics: Exploring the Role of Gut Microbiota in Obesity. Diabetes Metab Syndr Obes 2023; 16:3691-3705. [PMID: 38028999 PMCID: PMC10674108 DOI: 10.2147/dmso.s432344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/09/2023] [Indexed: 12/01/2023] Open
Abstract
Presently, obesity has emerged as a significant global public health concern due to its escalating prevalence and incidence rates. The gut microbiota, being a crucial environmental factor, has emerged as a key player in the etiology of obesity. Nevertheless, the intricate and specific interactions between obesity and gut microbiota, along with the underlying mechanisms, remain incompletely understood. This review comprehensively summarizes the gut microbiota characteristics in obesity, the mechanisms by which it induces obesity, and explores targeted therapies centered on gut microbiota restoration.
Collapse
Affiliation(s)
- Zequn Zhuang
- Department of General Surgery, the Affiliated Wuxi No.2 People’s Hospital of Nanjing Medical University, Wuxi, People’s Republic of China
| | - Peng Zhou
- Department of General Surgery, the Affiliated Wuxi No.2 People’s Hospital of Nanjing Medical University, Wuxi, People’s Republic of China
| | - Jing Wang
- Jiangnan University Medical Center, Wuxi, People’s Republic of China
| | - Xiaojing Lu
- Department of General Surgery, the Affiliated Wuxi No.2 People’s Hospital of Nanjing Medical University, Wuxi, People’s Republic of China
| | - Yigang Chen
- Department of General Surgery, the Affiliated Wuxi No.2 People’s Hospital of Nanjing Medical University, Wuxi, People’s Republic of China
- Jiangnan University Medical Center, Wuxi, People’s Republic of China
- Wuxi Clinical College, Nantong University, Wuxi, People’s Republic of China
| |
Collapse
|
3
|
Przybysz JT, DiBrog AM, Kern KA, Mukherjee A, Japa JE, Waite MH, Mietlicki-Baase EG. Macronutrient intake: Hormonal controls, pathological states, and methodological considerations. Appetite 2023; 180:106365. [PMID: 36347305 PMCID: PMC10563642 DOI: 10.1016/j.appet.2022.106365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/07/2022]
Abstract
A plethora of studies to date has examined the roles of feeding-related peptides in the control of food intake. However, the influence of these peptides on the intake of particular macronutrient constituents of food - carbohydrate, fat, and protein - has not been as extensively addressed in the literature. Here, the roles of several feeding-related peptides in controlling macronutrient intake are reviewed. Next, the relationship between macronutrient intake and diseases including diabetes mellitus, obesity, and eating disorders are examined. Finally, some key considerations in macronutrient intake research are discussed. We hope that this review will shed light onto this underappreciated topic in ingestive behavior research and will help to guide further scientific investigation in this area.
Collapse
Affiliation(s)
- Johnathan T Przybysz
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Adrianne M DiBrog
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Katherine A Kern
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Ashmita Mukherjee
- Psychology, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Jason E Japa
- Biotechnical and Clinical Laboratory Sciences, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Mariana H Waite
- Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Elizabeth G Mietlicki-Baase
- Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA; Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA.
| |
Collapse
|
4
|
Miyata S. Glial functions in the blood-brain communication at the circumventricular organs. Front Neurosci 2022; 16:991779. [PMID: 36278020 PMCID: PMC9583022 DOI: 10.3389/fnins.2022.991779] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The circumventricular organs (CVOs) are located around the brain ventricles, lack a blood-brain barrier (BBB) and sense blood-derived molecules. This review discusses recent advances in the importance of CVO functions, especially glial cells transferring periphery inflammation signals to the brain. The CVOs show size-limited vascular permeability, allowing the passage of molecules with molecular weight <10,000. This indicates that the lack of an endothelial cell barrier does not mean the free movement of blood-derived molecules into the CVO parenchyma. Astrocytes and tanycytes constitute a dense barrier at the distal CVO subdivision, preventing the free diffusion of blood-derived molecules into neighboring brain regions. Tanycytes in the CVOs mediate communication between cerebrospinal fluid and brain parenchyma via transcytosis. Microglia and macrophages of the CVOs are essential for transmitting peripheral information to other brain regions via toll-like receptor 2 (TLR2). Inhibition of TLR2 signaling or depletion of microglia and macrophages in the brain eliminates TLR2-dependent inflammatory responses. In contrast to TLR2, astrocytes and tanycytes in the CVOs of the brain are crucial for initiating lipopolysaccharide (LPS)-induced inflammatory responses via TLR4. Depletion of microglia and macrophages augments LPS-induced fever and chronic sickness responses. Microglia and macrophages in the CVOs are continuously activated, even under normal physiological conditions, as they exhibit activated morphology and express the M1/M2 marker proteins. Moreover, the microglial proliferation occurs in various regions, such as the hypothalamus, medulla oblongata, and telencephalon, with a marked increase in the CVOs, due to low-dose LPS administration, and after high-dose LPS administration, proliferation is seen in most brain regions, except for the cerebral cortex and hippocampus. A transient increase in the microglial population is beneficial during LPS-induced inflammation for attenuating sickness response. Transient receptor potential receptor vanilloid 1 expressed in astrocytes and tanycytes of the CVOs is responsible for thermoregulation upon exposure to a warm environment less than 37°C. Alternatively, Nax expressed in astrocytes and tanycytes of the CVOs is crucial for maintaining body fluid homeostasis. Thus, recent findings indicate that glial cells in the brain CVOs are essential for initiating neuroinflammatory responses and maintaining body fluid and thermal homeostasis.
Collapse
|
5
|
Lv X, Gao F, Li TP, Xue P, Wang X, Wan M, Hu B, Chen H, Jain A, Shao Z, Cao X. Skeleton interoception regulates bone and fat metabolism through hypothalamic neuroendocrine NPY. eLife 2021; 10:e70324. [PMID: 34468315 PMCID: PMC8439655 DOI: 10.7554/elife.70324] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 05/21/2021] [Indexed: 01/04/2023] Open
Abstract
The central nervous system regulates activity of peripheral organs through interoception. In our previous study, we have demonstrated that PGE2/EP4 skeleton interception regulate bone homeostasis. Here, we show that ascending skeleton interoceptive signaling downregulates expression of hypothalamic neuropeptide Y (NPY) and induce lipolysis of adipose tissue for osteoblastic bone formation. Specifically, the ascending skeleton interoceptive signaling induces expression of small heterodimer partner-interacting leucine zipper protein (SMILE) in the hypothalamus. SMILE binds to pCREB as a transcriptional heterodimer on Npy promoters to inhibit NPY expression. Knockout of EP4 in sensory nerve increases expression of NPY causing bone catabolism and fat anabolism. Importantly, inhibition of NPY Y1 receptor (Y1R) accelerated oxidation of free fatty acids in osteoblasts and rescued bone loss in AvilCre:Ptger4fl/fl mice. Thus, downregulation of hypothalamic NPY expression lipolyzes free fatty acids for anabolic bone formation through a neuroendocrine descending interoceptive regulation.
Collapse
Affiliation(s)
- Xiao Lv
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Feng Gao
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Tuo Peter Li
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Peng Xue
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Xiao Wang
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Mei Wan
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Bo Hu
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Hao Chen
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Amit Jain
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| | - Zengwu Shao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Xu Cao
- Department of Orthopaedic Surgery, Institute of Cell Engineering, and Department of Biomedical Engineering, The Johns Hopkins UniversityBaltimoreUnited States
| |
Collapse
|
6
|
Rautmann AW, de La Serre CB. Microbiota's Role in Diet-Driven Alterations in Food Intake: Satiety, Energy Balance, and Reward. Nutrients 2021; 13:nu13093067. [PMID: 34578945 PMCID: PMC8470213 DOI: 10.3390/nu13093067] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/18/2021] [Accepted: 08/25/2021] [Indexed: 02/07/2023] Open
Abstract
The gut microbiota plays a key role in modulating host physiology and behavior, particularly feeding behavior and energy homeostasis. There is accumulating evidence demonstrating a role for gut microbiota in the etiology of obesity. In human and rodent studies, obesity and high-energy feeding are most consistently found to be associated with decreased bacterial diversity, changes in main phyla relative abundances and increased presence of pro-inflammatory products. Diet-associated alterations in microbiome composition are linked with weight gain, adiposity, and changes in ingestive behavior. There are multiple pathways through which the microbiome influences food intake. This review discusses these pathways, including peripheral mechanisms such as the regulation of gut satiety peptide release and alterations in leptin and cholecystokinin signaling along the vagus nerve, as well as central mechanisms, such as the modulation of hypothalamic neuroinflammation and alterations in reward signaling. Most research currently focuses on determining the role of the microbiome in the development of obesity and using microbiome manipulation to prevent diet-induced increase in food intake. More studies are necessary to determine whether microbiome manipulation after prolonged energy-dense diet exposure and obesity can reduce intake and promote meaningful weight loss.
Collapse
|
7
|
Nambu Y, Ohira K, Morita M, Yasumoto H, Kurganov E, Miyata S. Effects of leptin on proliferation of astrocyte- and tanycyte-like neural stem cells in the adult mouse medulla oblongata. Neurosci Res 2021; 173:44-53. [PMID: 34058263 DOI: 10.1016/j.neures.2021.05.012] [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: 03/08/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 10/21/2022]
Abstract
Astrocyte- and tanycyte-like neural stem cells (NSCs) were recently detected in the area postrema (AP) and central canal (CC) of the adult medulla oblongata, respectively. The present study aimed to examine dynamical behaviors of the astrocyte- and tanycyte-like NSCs of the mouse medulla oblongata to leptin. The neurosphere assay identified astrocytes in the AP and tanycytes in the CC as NSCs based on their self-renewing neurospherogenic potential. Both NSCs in neurosphere cultures were multipotent cells that generate astrocytes, oligodendrocytes, and neurons. Astrocyte-like NSCs actively proliferated and tanycyte-like NSCs were quiescent under physiologically-relevant in vivo conditions. Chronic leptin treatment promoted proliferation of astrocyte-like NSCs in the AP both in vitro and in vivo. Leptin receptors were expressed in astrocyte-like, but not tanycyte-like NSCs. Food deprivation significantly diminished proliferation of astrocyte-like NSCs. Therefore, the present study indicates that proliferation of astrocyte-like, but not tanycyte-like NSCs is regulated by nutritional conditions.
Collapse
Affiliation(s)
- Yuri Nambu
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Koji Ohira
- Laboratory of Nutritional Brain Science, Department of Food Science and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | - Mitsuhiro Morita
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Hiroki Yasumoto
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Erkin Kurganov
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Seiji Miyata
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
| |
Collapse
|
8
|
Korf HW, Møller M. Arcuate nucleus, median eminence, and hypophysial pars tuberalis. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:227-251. [PMID: 34225932 DOI: 10.1016/b978-0-12-820107-7.00015-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The arcuate nucleus (ARC) is located in the mediobasal hypothalamus and forms a morphological and functional entity with the median eminence (ME), the ARC-ME. The ARC comprises several distinct types of neurons controlling prolactin release, food intake, and metabolism as well as reproduction and onset of puberty. The ME lacks a blood-brain barrier and provides an entry for peripheral signals (nutrients, leptin, ghrelin). ARC neurons are adjacent to the wall of the third ventricle. This facilitates the exchange of signals from and to the cerebrospinal fluid. The ventricular wall is composed of tanycytes that serve different functions. Axons of ARC neurons contribute to the tuberoinfundibular tract terminating in the ME on the hypophysial portal vessels (HPV) and establish one of the neurohumoral links between the hypothalamus and the pituitary. ARC neurons are reciprocally connected with several other hypothalamic nuclei, the brainstem, and reward pathways. The hypophysial pars tuberalis (PT) is attached to the ME and the HPV. The PT, an important interface of the neuroendocrine system, is mandatory for the control of seasonal functions. This contribution provides an update of our knowledge about the ARC-ME complex and the PT which, inter alia, is needed to understand the pathophysiology of metabolic diseases and reproduction.
Collapse
Affiliation(s)
- Horst-Werner Korf
- Center for Anatomy and Brain Research, Institute for Anatomy, Düsseldorf, Germany.
| | - Morten Møller
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
9
|
Navarro I Batista K, Schraner M, Riediger T. Brainstem prolactin-releasing peptide contributes to cancer anorexia-cachexia syndrome in rats. Neuropharmacology 2020; 180:108289. [PMID: 32890590 DOI: 10.1016/j.neuropharm.2020.108289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/05/2020] [Accepted: 08/25/2020] [Indexed: 11/26/2022]
Abstract
Up to 80% of cancer patients are affected by the cancer anorexia-cachexia syndrome (CACS), which leads to excessive body weight loss, reduced treatment success and increased lethality. The area postrema/nucleus of the solitary tract (AP/NTS) region emerged as a central nervous key structure in this multi-factorial process. Neurons in this area are targeted by cytokines and signal to downstream sites involved in energy homeostasis. NTS neurons expressing prolactin-releasing peptide (PrRP) are implicated in the control of energy intake and hypothalamus-pituitary-adrenal (HPA) axis activation, which contributes to muscle wasting. To explore if brainstem PrRP neurons contribute to CACS, we selectively knocked down PrRP expression in the NTS of hepatoma tumor-bearing rats by an AAV/shRNA gene silencing approach. PrRP knockdown reduced body weight loss and anorexia compared to tumor-bearing controls treated with a non-silencing AAV. Gastrocnemius and total hind limb muscle weight was higher in PrPR knockdown rats. Corticosterone levels were increased in the early phase after tumor induction at day 6 in both groups but returned to baseline levels at day 21 in the PrRP knockdown group. While we did not detect significant changes in gene expression of markers for muscle protein metabolism (MuRF-1, myostatin, mTOR and REDD1), mTOR and REDD1 tended to be lower after disruption PrRP signalling. In conclusion, we identified brainstem PrRP as a possible neuropeptide mediator of CACS in hepatoma tumor-bearing rats. The central and peripheral downstream mechanisms require further investigation and might involve HPA axis activation.
Collapse
Affiliation(s)
| | - Marissa Schraner
- University of Zurich, Institute of Veterinary Physiology, Zurich, Switzerland
| | - Thomas Riediger
- University of Zurich, Institute of Veterinary Physiology, Zurich, Switzerland.
| |
Collapse
|
10
|
Oral gavage of capsaicin causes TRPV1-dependent acute hypothermia and TRPV1-independent long-lasting increase of locomotor activity in the mouse. Physiol Behav 2019; 206:213-224. [DOI: 10.1016/j.physbeh.2019.04.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 02/20/2019] [Accepted: 04/17/2019] [Indexed: 12/18/2022]
|
11
|
Diet-induced adaptive thermogenesis requires neuropeptide FF receptor-2 signalling. Nat Commun 2018; 9:4722. [PMID: 30413707 PMCID: PMC6226433 DOI: 10.1038/s41467-018-06462-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 09/07/2018] [Indexed: 11/24/2022] Open
Abstract
Excess caloric intake results in increased fat accumulation and an increase in energy expenditure via diet-induced adaptive thermogenesis; however, the underlying mechanisms controlling these processes are unclear. Here we identify the neuropeptide FF receptor-2 (NPFFR2) as a critical regulator of diet-induced thermogenesis and bone homoeostasis. Npffr2−/− mice exhibit a stronger bone phenotype and when fed a HFD display exacerbated obesity associated with a failure in activating brown adipose tissue (BAT) thermogenic response to energy excess, whereas the activation of cold-induced BAT thermogenesis is unaffected. NPFFR2 signalling is required to maintain basal arcuate nucleus NPY mRNA expression. Lack of NPFFR2 signalling leads to a decrease in BAT thermogenesis under HFD conditions with significantly lower UCP-1 and PGC-1α levels in the BAT. Together, these data demonstrate that NPFFR2 signalling promotes diet-induced thermogenesis via a novel hypothalamic NPY-dependent circuitry thereby coupling energy homoeostasis with energy partitioning to adipose and bone tissue. Excess caloric intake leads to increased thermogenesis in brown adipose tissue, to limit weight gain. Here, the authors show that neuropeptide FF receptor-2 signalling promotes thermogenesis via control of NPY expression in the arcuate nucleus, and that it absence in mice leads to a failure of activation of diet-induced thermogenesis and the development of exacerbated obesity.
Collapse
|
12
|
Velasco C, Blanco AM, Unniappan S, Soengas JL. The anorectic effect of central PYY 1-36 treatment in rainbow trout (Oncorhynchus mykiss) is associated with changes in mRNAs encoding neuropeptides and parameters related to fatty acid sensing and metabolism. Gen Comp Endocrinol 2018; 267:137-145. [PMID: 29940182 DOI: 10.1016/j.ygcen.2018.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/18/2018] [Accepted: 06/21/2018] [Indexed: 12/21/2022]
Abstract
We hypothesized that peptide YY (PYY) is involved in the metabolic regulation of food intake in fish. Therefore, we assessed in rainbow trout (Oncorhynchus mykiss) the effects of intracerebroventricular treatment with 10 ng/g PYY1-36 on food intake, expression of neuropeptides involved in food intake control, and the activity of fatty acid-sensing systems. The administration of PYY1-36 caused a significant reduction in food intake up to 24 h post-treatment. This anorectic action was associated with changes 2 h after treatment in mRNA abundance of neuropeptides involved in metabolic regulation of food intake in hypothalamus (decreased NPY and raised CART values) and hindbrain (increased POMCa1 values). We also observed that PYY1-36 treatment induced changes in mRNA abundance of parameters related to fatty acid sensing and metabolism in hypothalamus (decreased values of ACLY, PPARγ, and SREBP1c) and hindbrain (increased values of LPL, FAT/CD36, PPARα, PPARγ, and SREBP1c and decreased values of UCP2a). PYY1-36 treatment also increased mRNA abundance of mTOR. In general, it seems that mRNAs encoding some components of the machinery required for fatty acid sensing and metabolism are activated by PYY1-36. The response observed was higher in the hindbrain than in the hypothalamus, supporting the greater importance of this brain area in mediating the modulatory effects of gastrointestinal hormones on feeding regulation.
Collapse
Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain; Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada
| | - Ayelén M Blanco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain; Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada
| | - Suraj Unniappan
- Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada.
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| |
Collapse
|
13
|
Walley SN, Roepke TA. Perinatal exposure to endocrine disrupting compounds and the control of feeding behavior-An overview. Horm Behav 2018; 101:22-28. [PMID: 29107582 PMCID: PMC5938167 DOI: 10.1016/j.yhbeh.2017.10.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/21/2017] [Accepted: 10/23/2017] [Indexed: 02/07/2023]
Abstract
Endocrine disrupting compounds (EDC) are ubiquitous environmental contaminants that can interact with steroid and nuclear receptors or alter hormone production. Many studies have reported that perinatal exposure to EDC including bisphenol A, PCB, dioxins, and DDT disrupt energy balance, body weight, adiposity, or glucose homeostasis in rodent offspring. However, little information exists on the effects of perinatal EDC exposure on the control of feeding behaviors and meal pattern (size, frequency, duration), which may contribute to their obesogenic properties. Feeding behaviors are controlled centrally through communication between the hindbrain and hypothalamus with inputs from the emotion and reward centers of the brain and modulated by peripheral hormones like ghrelin and leptin. Discrete hypothalamic nuclei (arcuate nucleus, paraventricular nucleus, lateral and dorsomedial hypothalamus, and ventromedial nucleus) project numerous reciprocal neural connections between each other and to other brain regions including the hindbrain (nucleus tractus solitarius and parabrachial nucleus). Most studies on the effects of perinatal EDC exposure examine simple crude food intake over the course of the experiment or for a short period in adult models. In addition, these studies do not examine EDC's impacts on the feeding neurocircuitry of the hypothalamus-hindbrain, the response to peripheral hormones (leptin, ghrelin, cholecystokinin, etc.) after refeeding, or other feeding behavior paradigms. The purpose of this review is to discuss those few studies that report crude food or energy intake after perinatal EDC exposure and to explore the need for deeper investigations in the hypothalamic-hindbrain neurocircuitry and discrete feeding behaviors.
Collapse
Affiliation(s)
- Sabrina N Walley
- Joint Graduate Program in Toxicology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Troy A Roepke
- Department of Animal Sciences, School of Environmental & Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA; Joint Graduate Program in Toxicology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
| |
Collapse
|
14
|
Abegg K, Bernasconi L, Hutter M, Whiting L, Pietra C, Giuliano C, Lutz TA, Riediger T. Ghrelin receptor inverse agonists as a novel therapeutic approach against obesity-related metabolic disease. Diabetes Obes Metab 2017; 19:1740-1750. [PMID: 28544245 DOI: 10.1111/dom.13020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 05/18/2017] [Accepted: 05/20/2017] [Indexed: 12/31/2022]
Abstract
AIMS Ghrelin is implicated in the control of energy balance and glucose homeostasis. The ghrelin receptor exhibits ligand-independent constitutive activity, which can be pharmacologically exploited to induce inverse ghrelin actions. Because ghrelin receptor inverse agonists (GHSR-IA) might be effective for the treatment of obesity-related metabolic disease, we tested 2 novel synthetic compounds GHSR-IA1 and GHSR-IA2. MATERIALS AND METHODS In functional cell assays, electrophysiogical and immunohistochemical experiments, we demonstrated inverse agonist activity for GHSR-IA1 and GHSR-IA2. We used healthy mice, Zucker diabetic fatty (ZDF) rats and diet-induced obese (DIO) mice to explore effects on food intake (FI), body weight (BW), conditioned taste aversion (CTA), oral glucose tolerance (OGT), pancreatic islet morphology, hepatic steatosis (HS), and blood lipids. RESULTS Both compounds acutely reduced FI in mice without inducing CTA. Chronic GHSR-IA1 increased metabolic rate in chow-fed mice, suppressed FI, and improved OGT in ZDF rats. Moreover, the progression of islet hyperplasia to fibrosis in ZDF rats slowed down. GHSR-IA2 reduced FI and BW in DIO mice, and reduced fasting and stimulated glucose levels compared with pair-fed and vehicle-treated mice. GHSR-IA2-treated DIO mice showed decreased blood lipids. GHSR-IA1 treatment markedly decreased HS in DIO mice. CONCLUSIONS Our study demonstrates therapeutic actions of novel ghrelin receptor inverse agonists, suggesting a potential to treat obesity-related metabolic disorders including diabetes mellitus.
Collapse
Affiliation(s)
- Kathrin Abegg
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Lara Bernasconi
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Melanie Hutter
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Lynda Whiting
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Claudio Pietra
- Research and Preclinical Development Department, Helsinn SA, Lugano, Switzerland
| | - Claudio Giuliano
- Research and Preclinical Development Department, Helsinn SA, Lugano, Switzerland
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Thomas Riediger
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| |
Collapse
|
15
|
Farias G, Netto BDM, Bettini SC, Dâmaso AR, de Freitas ACT. Neuroendocrine regulation of energy balance: Implications on the development and surgical treatment of obesity. Nutr Health 2017; 23:131-146. [PMID: 28838280 DOI: 10.1177/0260106017719369] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
INTRODUCTION Obesity, a serious public health problem, occurs mainly when food consumption exceeds energy expenditure. Therefore, energy balance depends on the regulation of the hunger-satiety mechanism, which involves interconnection of the central nervous system and peripheral signals from the adipose tissue, pancreas and gastrointestinal tract, generating responses in short-term food intake and long-term energy balance. Increased body fat alters the gut- and adipose-tissue-derived hormone signaling, which promotes modifications in appetite-regulating hormones, decreasing satiety and increasing hunger senses. With the failure of conventional weight loss interventions (dietary treatment, exercise, drugs and lifestyle modifications), bariatric surgeries are well-accepted tools for the treatment of severe obesity, with long-term and sustained weight loss. Bariatric surgeries may cause weight loss due to restriction/malabsorption of nutrients from the anatomical alteration of the gastrointestinal tract that decreases energy intake, but also by other physiological factors associated with better results of the surgical procedure. OBJECTIVE This review discusses the neuroendocrine regulation of energy balance, with description of the predominant hormones and peptides involved in the control of energy balance in obesity and all currently available bariatric surgeries. CONCLUSIONS According to the findings of our review, bariatric surgeries promote effective and sustained weight loss not only by reducing calorie intake, but also by precipitating changes in appetite control, satiation and satiety, and physiological changes in gut-, neuro- and adipose-tissue-derived hormone signaling.
Collapse
Affiliation(s)
- Gisele Farias
- 1 Department of Surgery, Universidade Federal do Paraná, UFPR, Curitiba-Pr, Brazil
| | | | - Solange Cravo Bettini
- 3 Federal University of Paraná (UFPR), Gastrointestinal Surgery Service of Hospital de Clínicas, Curitiba-PR, Brazil
| | | | | |
Collapse
|
16
|
Wang L, Jacobs JP, Lagishetty V, Yuan PQ, Wu SV, Million M, Reeve JR, Pisegna JR, Taché Y. High-protein diet improves sensitivity to cholecystokinin and shifts the cecal microbiome without altering brain inflammation in diet-induced obesity in rats. Am J Physiol Regul Integr Comp Physiol 2017; 313:R473-R486. [PMID: 28724546 DOI: 10.1152/ajpregu.00105.2017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/14/2017] [Accepted: 07/14/2017] [Indexed: 12/14/2022]
Abstract
High-protein diet (HPD) curtails obesity and/or fat mass, but it is unknown whether it reverses neuroinflammation or alters glucose levels, CCK sensitivity, and gut microbiome in rats fed a Western diet (WD)-induced obesity (DIO). Male rats fed a WD (high fat and sugar) for 12 wk were switched to a HPD for 6 wk. Body composition, food intake, meal pattern, sensitivity to intraperitoneal CCK-8S, blood glucose, brain signaling, and cecal microbiota were assessed. When compared with a normal diet, WD increased body weight (9.3%) and fat mass (73.4%). CCK-8S (1.8 or 5.2 nmol/kg) did not alter food intake and meal pattern in DIO rats. Switching to a HPD for 6 wk reduced fat mass (15.7%) with a nonsignificantly reduced body weight gain, normalized blood glucose, and decreased feeding after CCK-8S. DIO rats on the WD or switched to a HPD showed comparable microbial diversity. However, in HPD versus WD rats, there was enrichment of 114 operational taxonomic units (OTUs) and depletion of 188 OTUs. Of those, Akkermansia muciniphila (enriched on a HPD), an unclassified Clostridiales, a member of the RF39 order, and a Phascolarctobacterium were significantly associated with fat mass. The WD increased cytokine expression in the hypothalamus and dorsal medulla that was unchanged by switching to HPD. These data indicate that HPD reduces body fat and restores glucose homeostasis and CCK sensitivity, while not modifying brain inflammation. In addition, expansion of cecal Akkermansia muciniphila correlated to fat mass loss may represent a potential peripheral mechanism of HPD beneficial effects.
Collapse
Affiliation(s)
- Lixin Wang
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Jonathan P Jacobs
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Venu Lagishetty
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Pu-Qing Yuan
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Shuping V Wu
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Mulugeta Million
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Joseph R Reeve
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Joseph R Pisegna
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and.,Division of Gastroenterology, Hepatology and Parenteral Nutrition, and Research and Development, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California
| | - Yvette Taché
- CURE/Digestive Diseases Research Center and Center for Neurobiology of Stress and Resilience, Department of Medicine, Vatche and Tamar Manoukian Digestive Diseases Division, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| |
Collapse
|
17
|
Role of the area postrema in the hypophagic effects of oleoylethanolamide. Pharmacol Res 2017; 122:20-34. [PMID: 28535974 DOI: 10.1016/j.phrs.2017.05.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/10/2017] [Accepted: 05/16/2017] [Indexed: 12/25/2022]
Abstract
The satiety-promoting action of oleoylethanolamide (OEA) has been associated to the indirect activation of selected brain areas, such as the nucleus of the solitary tract (NST) in the brainstem and the tuberomammillary (TMN) and paraventricular (PVN) nuclei in the hypothalamus, where noradrenergic, histaminergic and oxytocinergic neurons play a necessary role. Visceral ascending fibers were hypothesized to mediate such effects. However, our previous findings demonstrated that the hypophagic action of peripherally administered OEA does not require intact vagal afferents and is associated to a strong activation of the area postrema (AP). Therefore, we hypothesized that OEA may exert its central effects through the direct activation of this circumventricular organ. To test this hypothesis, we subjected rats to the surgical ablation of the AP (APX rats) and evaluated the effects of OEA (10mgkg-1 i.p.) on food intake, Fos expression, hypothalamic oxytocin (OXY) immunoreactivity and on the expression of dopamine beta hydroxylase (DBH) in the brainstem and hypothalamus. We found that the AP lesion completely prevented OEA's behavioral and neurochemical effects in the brainstem and the hypothalamus. Moreover OEA increased DBH expression in AP and NST neurons of SHAM rats while the effect in the NST was absent in APX rats, thus suggesting the possible involvement of noradrenergic AP neurons. These results support the hypothesis of a necessary role of the AP in mediating OEA's central effects that sustain its pro-satiety action.
Collapse
|
18
|
Oral Treatment with the Ghrelin Receptor Agonist HM01 Attenuates Cachexia in Mice Bearing Colon-26 (C26) Tumors. Int J Mol Sci 2017; 18:ijms18050986. [PMID: 28475119 PMCID: PMC5454899 DOI: 10.3390/ijms18050986] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/03/2017] [Accepted: 04/29/2017] [Indexed: 01/13/2023] Open
Abstract
The gastrointestinal hormone ghrelin reduces energy expenditure and stimulates food intake. Ghrelin analogs are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to investigate whether oral treatment with the non-peptidergic ghrelin receptor agonist HM01 counteracts CACS in colon-26 (C26) tumor-bearing mice. The C26 tumor model is characterized by pronounced body weight (BW) loss and muscle wasting in the absence of severe anorexia. We analyzed the time course of BW loss, body composition, muscle mass, bone mineral density, and the cytokines interleukin-6 (IL-6) and macrophage-inhibitory cytokine-1 (MIC-1). Moreover, we measured the expression of the muscle degradation markers muscle RING-finger-protein-1 (MuRF-1) and muscle atrophy F-box (MAFbx). After tumor inoculation, MIC-1 levels increased earlier than IL-6 and both cytokines were elevated before MuRF-1/MAFbx expression increased. Oral HM01 treatment increased BW, fat mass, and neuronal hypothalamic activity in healthy mice. In tumor-bearing mice, HM01 increased food intake, BW, fat mass, muscle mass, and bone mineral density while it decreased energy expenditure. These effects appeared to be independent of IL-6, MIC-1, MuRF-1 or MAFbx, which were not affected by HM01. Therefore, HM01 counteracts cachectic body weight loss under inflammatory conditions and is a promising compound for the treatment of cancer cachexia in the absence of severe anorexia.
Collapse
|
19
|
MacLean PS, Blundell JE, Mennella JA, Batterham RL. Biological control of appetite: A daunting complexity. Obesity (Silver Spring) 2017; 25 Suppl 1:S8-S16. [PMID: 28229538 PMCID: PMC5407690 DOI: 10.1002/oby.21771] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 12/20/2016] [Indexed: 01/01/2023]
Abstract
OBJECTIVE This review summarizes a portion of the discussions of an NIH Workshop (Bethesda, MD, 2015) titled "Self-Regulation of Appetite-It's Complicated," which focused on the biological aspects of appetite regulation. METHODS This review summarizes the key biological inputs of appetite regulation and their implications for body weight regulation. RESULTS These discussions offer an update of the long-held, rigid perspective of an "adipocentric" biological control, taking a broader view that also includes important inputs from the digestive tract, from lean mass, and from the chemical sensory systems underlying taste and smell. It is only beginning to be understood how these biological systems are integrated and how this integrated input influences appetite and food eating behaviors. The relevance of these biological inputs was discussed primarily in the context of obesity and the problem of weight regain, touching on topics related to the biological predisposition for obesity and the impact that obesity treatments (dieting, exercise, bariatric surgery, etc.) might have on appetite and weight loss maintenance. Finally considered is a common theme that pervaded the workshop discussions, which was individual variability. CONCLUSIONS It is this individual variability in the predisposition for obesity and in the biological response to weight loss that makes the biological component of appetite regulation so complicated. When this individual biological variability is placed in the context of the diverse environmental and behavioral pressures that also influence food eating behaviors, it is easy to appreciate the daunting complexities that arise with the self-regulation of appetite.
Collapse
Affiliation(s)
- Paul S. MacLean
- University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - John E. Blundell
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK
| | | | - Rachel L. Batterham
- Centre for Obesity Research, Rayne Institute, University College London, London WC1E 6JJ, UK
- National Institute of Health Research, University College London Hospital Biomedical Research Centre, London W1T 7DN, UK
| |
Collapse
|
20
|
Early effects of Roux-en-Y gastric bypass on peptides and hormones involved in the control of energy balance. Eur J Gastroenterol Hepatol 2016; 28:1050-5. [PMID: 27203601 DOI: 10.1097/meg.0000000000000665] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Body weight varies depending on the prevailing direction of environmental pressures; however, physiological factors also play a significant role in the control of body weight. The aim of the present study was to assess the impact of Roux-en-Y gastric bypass (RYGB) on hormones and peptides involved in the control of energy balance and their possible implications in appetite/satiety. METHODS The sample included 39 individuals with extreme obesity (37 women and two men) who underwent RYGB. Anthropometric and biochemical markers were collected before surgery and 6 months after RYGB. RESULTS The BMI decreased from 44.3±6.4 to 31.7±5.7 kg/m (P<0.001) at the sixth month. Percentage of excess weight lost was 63.2±25.0%. Leptin and glucose levels decreased significantly 6 months after RYGB (P<0.001). Interestingly, a significant correlation was confirmed between the anorexigenic gut hormone peptide YY (PYY) and the central anorexigenic mediator α-melanocyte-stimulating hormone after 6 months of RYGB (r=0.35, P=0.004). In contrast, PYY concentrations were correlated negatively with BMI (r=-0.34, P=0.002). CONCLUSION In the present investigation, it was found that there is a relationship between α-melanocyte-stimulating hormone and PYY concentrations, and it supports the role of the PYY to POMC signal in appetite regulation after RYGB.
Collapse
|
21
|
Abstract
Successfully rearing young places multiple demands on the mammalian female. These are met by a wide array of alterations in maternal physiology and behavior that are coordinated with the needs of the developing young, and include adaptations in neuroendocrine systems not directly involved in maternal behavior or lactation. In this article, attenuations in the behavioral and neuroendocrine responses to stressors, the alterations in metabolic pathways facilitating both increased food intake and conservation of energy, and the changes in fertility that occur postpartum are described. The mechanisms underlying these processes as well as the factors that contribute to them and the relative contributions of these stimuli at different times postpartum are also reviewed. The induction and maintenance of the adaptations observed in the postpartum maternal brain are dependent on mother-young interaction and, in most cases, on suckling stimulation and its consequences for the hormonal profile of the mother. The peptide hormone prolactin acting on receptors within the brain makes a major contribution to changes in metabolic pathways, suppression of fertility and the attenuation of the neuroendocrine response to stress during lactation. Oxytocin is also released, both into the circulation and in some hypothalamic nuclei, in response to suckling stimulation and this hormone has been implicated in the decrease in anxiety behavior seen in the early postpartum period. The relative importance of these hormones changes across lactation and it is becoming increasingly clear that many of the adaptations to motherhood reviewed here reflect the outcome of multiple influences. © 2016 American Physiological Society. Compr Physiol 6:1493-1518, 2016.
Collapse
Affiliation(s)
- Barbara Woodside
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, Quebec, Canada
| |
Collapse
|
22
|
Borner T, Loi L, Pietra C, Giuliano C, Lutz TA, Riediger T. The ghrelin receptor agonist HM01 mimics the neuronal effects of ghrelin in the arcuate nucleus and attenuates anorexia-cachexia syndrome in tumor-bearing rats. Am J Physiol Regul Integr Comp Physiol 2016; 311:R89-96. [PMID: 27147616 DOI: 10.1152/ajpregu.00044.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 05/02/2016] [Indexed: 11/22/2022]
Abstract
The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 μg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia.
Collapse
Affiliation(s)
- Tito Borner
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Zurich Center of Human Integrative Physiology, University of Zurich, Zurich, Switzerland; and
| | - Laura Loi
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Claudio Pietra
- Helsinn Healthcare SA, Zurich Center of Integrative Human Physiology, Lugano, Switzerland
| | - Claudio Giuliano
- Helsinn Healthcare SA, Zurich Center of Integrative Human Physiology, Lugano, Switzerland
| | - Thomas A Lutz
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Zurich Center of Human Integrative Physiology, University of Zurich, Zurich, Switzerland; and
| | - Thomas Riediger
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; Zurich Center of Human Integrative Physiology, University of Zurich, Zurich, Switzerland; and
| |
Collapse
|
23
|
Pollatzek E, Hitzel N, Ott D, Raisl K, Reuter B, Gerstberger R. Functional expression of P2 purinoceptors in a primary neuroglial cell culture of the rat arcuate nucleus. Neuroscience 2016; 327:95-114. [PMID: 27072848 DOI: 10.1016/j.neuroscience.2016.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 04/06/2016] [Accepted: 04/06/2016] [Indexed: 12/22/2022]
Abstract
The arcuate nucleus (ARC) plays an important role in the hypothalamic control of energy homeostasis. Expression of various purinoceptor subtypes in the rat ARC and physiological studies suggest a modulatory function of P2 receptors within the neuroglial ARC circuitry. A differentiated mixed neuronal and glial microculture was therefore established from postnatal rat ARC, revealing neuronal expression of ARC-specific transmitters involved in food intake regulation (neuropeptide Y (NPY), proopiomelanocortin (POMC), tyrosine hydroxylase (TH)). Some NPYergic neurons cosynthesized TH, while POMC and TH expression proved to be mutually exclusive. Stimulation with the general purinoceptor agonists 2-methylthioadenosine-5'triphosphate (2-MeSATP) and ATP but not the P2X1/P2X3 receptor subtype agonist α,β-methyleneadenosine-5'triphosphate (α,β-meATP) induced intracellular calcium signals in ARC neurons and astrocytes. Some 5-10% each of 2-MeSATP responsive neurons expressed POMC, NYP or TH. Supporting the calcium imaging data, radioligand binding studies to hypothalamic membranes showed high affinity for 2-MeSATP, ATP but not α,β-meATP to displace [α-(35)S]deoxyadenosine-5'thiotriphosphate ([(35)S]dATPαS) from P2 receptors. Repetitive superfusion with equimolar 2-MeSATP allowed categorization of ARC cells into groups with a high or low (LDD) degree of purinoceptor desensitization, the latter allowing further receptor characterization. Calcium imaging experiments performed at 37°C vs. room temperature showed further reduction of desensitization. Agonist-mediated intracellular calcium signals were suppressed in all LDD neurons but only 25% of astrocytes in the absence of extracellular calcium, suggestive of metabotropic P2Y receptor expression in the majority of ARC astrocytes. The highly P2Y1-selective receptor agonists MRS2365 and 2-methylthioadenosine-5'diphosphate (2-MeSADP) activated 75-85% of all 2-MeSATP-responsive ARC astrocytes. Taking into consideration the high potency to dose-dependently stimulate ARC cells of the LDD group, the high affinity for rat P2X(1-3) and low affinity for rat P2X4, P2X7 and P2Y receptor subtypes except P2Y1 and P2Y13, the agonist 2-MeSATP primarily acted upon P2X2 and P2Y1 purinoceptors to trigger intracellular calcium signaling in ARC neurons and astrocytes.
Collapse
Affiliation(s)
- Eric Pollatzek
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| | - Norma Hitzel
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| | - Daniela Ott
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| | - Katrin Raisl
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| | - Bärbel Reuter
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| | - Rüdiger Gerstberger
- Institut für Veterinär-Physiologie und -Biochemie, Justus-Liebig-Universität Giessen, Frankfurter Strasse 100, D-35392 Giessen, Deutschland.
| |
Collapse
|
24
|
Welcome MO, Mastorakis NE, Pereverzev VA. Sweet-Taste Receptor Signaling Network and Low-Calorie Sweeteners. REFERENCE SERIES IN PHYTOCHEMISTRY 2016. [DOI: 10.1007/978-3-319-26478-3_25-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
25
|
Park HK, Ahima RS. Physiology of leptin: energy homeostasis, neuroendocrine function and metabolism. Metabolism 2015; 64:24-34. [PMID: 25199978 PMCID: PMC4267898 DOI: 10.1016/j.metabol.2014.08.004] [Citation(s) in RCA: 390] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 08/01/2014] [Accepted: 08/08/2014] [Indexed: 12/24/2022]
Abstract
Leptin is secreted by adipose tissue and regulates energy homeostasis, neuroendocrine function, metabolism, immune function and other systems through its effects on the central nervous system and peripheral tissues. Leptin administration has been shown to restore metabolic and neuroendocrine abnormalities in individuals with leptin-deficient states, including hypothalamic amenorrhea and lipoatrophy. In contrast, obese individuals are resistant to leptin. Recombinant leptin is beneficial in patients with congenital leptin deficiency or generalized lipodystrophy. However, further research on molecular mediators of leptin resistance is needed for the development of targeted leptin sensitizing therapies for obesity and related metabolic diseases.
Collapse
Affiliation(s)
- Hyeong-Kyu Park
- Department of Internal Medicine, Soonchunhyang University College of Medicine, Seoul, Republic of Korea
| | - Rexford S Ahima
- Division of Endocrinology, Diabetes and Metabolism, and the Institute for Diabetes, Obesity and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
26
|
Chronic activation of central AMPK attenuates glucose-stimulated insulin secretion and exacerbates hepatic insulin resistance in diabetic rats. Brain Res Bull 2014; 108:18-26. [PMID: 25149877 DOI: 10.1016/j.brainresbull.2014.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/08/2014] [Accepted: 08/11/2014] [Indexed: 01/04/2023]
Abstract
We investigated the effects of chronic AMP-activated kinase (AMPK) activation in the hypothalamus on energy and glucose metabolism in 90% pancreatectomized diabetic rats. Diabetic rats fed a high fat diet were divided into 3 groups and intracerebroventricular (ICV) administered with one of the following: 5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide (AICAR, AMPK activator; 80 μg/day), AICAR+compound C (AMPK inhibitor; 6.2 μg/day), or an artificial cerebrospinal fluid (control) by means of osmotic pumps for 4 weeks. In the hypothalamus, central AICAR activated the phosphorylation of AMPK whereas adding compound C suppressed the activation. AICAR increased body weight and epididymal and retroperitoneal fat mass by increasing energy intake for the first 2 weeks and decreasing energy expenditure, whereas compound C reversed the AICAR effect on energy metabolism. Indirect calorimetry revealed that ICV-AICAR decreased carbohydrate oxidation, but not fat oxidation, compared to the control. During euglycemic hyperinsulinemic clamp, central AICAR increased hepatic glucose output at hyperinsulinemic states. ICV-AICAR increased expressions of hepatic genes involved in fatty acid synthesis and decreased expression of hepatic genes related to thermogenesis whereas compound C nullified the AICAR effect. Insulin secretion in the first and second phases decreased in AICAR-treated rats at hyperglycemic clamp, but compound C nullified the decrease. However, central AICAR did not alter β-cell mass via its proliferation or apoptosis. In conclusion, chronic hypothalamic AMPK activation impaired energy metabolism and glucose homeostasis by increasing food intake, increasing hepatic glucose output and decreasing insulin secretion in diabetic rats. The impairment of energy and glucose homeostasis by AMPK activation was nullified by an AMPK inhibitor.
Collapse
|
27
|
Giordano C, Marchiò M, Timofeeva E, Biagini G. Neuroactive peptides as putative mediators of antiepileptic ketogenic diets. Front Neurol 2014; 5:63. [PMID: 24808888 PMCID: PMC4010764 DOI: 10.3389/fneur.2014.00063] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 04/14/2014] [Indexed: 12/14/2022] Open
Abstract
Various ketogenic diet (KD) therapies, including classic KD, medium chain triglyceride administration, low glycemic index treatment, and a modified Atkins diet, have been suggested as useful in patients affected by pharmacoresistant epilepsy. A common goal of these approaches is to achieve an adequate decrease in the plasma glucose level combined with ketogenesis, in order to mimic the metabolic state of fasting. Although several metabolic hypotheses have been advanced to explain the anticonvulsant effect of KDs, including changes in the plasma levels of ketone bodies, polyunsaturated fatty acids, and brain pH, direct modulation of neurotransmitter release, especially purinergic (i.e., adenosine) and γ-aminobutyric acidergic neurotransmission, was also postulated. Neuropeptides and peptide hormones are potent modulators of synaptic activity, and their levels are regulated by metabolic states. This is the case for neuroactive peptides such as neuropeptide Y, galanin, cholecystokinin, and peptide hormones such as leptin, adiponectin, and growth hormone-releasing peptides (GHRPs). In particular, the GHRP ghrelin and its related peptide des-acyl ghrelin are well-known controllers of energy homeostasis, food intake, and lipid metabolism. Notably, ghrelin has also been shown to regulate the neuronal excitability and epileptic activation of neuronal networks. Several lines of evidence suggest that GHRPs are upregulated in response to starvation and, particularly, in patients affected by anorexia and cachexia, all conditions in which also ketone bodies are upregulated. Moreover, starvation and anorexia nervosa are accompanied by changes in other peptide hormones such as adiponectin, which has received less attention. Adipocytokines such as adiponectin have also been involved in modulating epileptic activity. Thus, neuroactive peptides whose plasma levels and activity change in the presence of ketogenesis might be potential candidates for elucidating the neurohormonal mechanisms involved in the beneficial effects of KDs. In this review, we summarize the current evidence for altered regulation of the synthesis of neuropeptides and peripheral hormones in response to KDs, and we try to define a possible role for specific neuroactive peptides in mediating the antiepileptic properties of diet-induced ketogenesis.
Collapse
Affiliation(s)
- Carmela Giordano
- Laboratory of Experimental Epileptology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Maddalena Marchiò
- Laboratory of Experimental Epileptology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Neuropediatric Unit, Department of Medical and Surgical Sciences for Children and Adults, Policlinico Hospital, University of Modena and Reggio Emilia, Modena, Italy
- Department of Neurosciences, NOCSAE Hospital, Modena, Italy
| | - Elena Timofeeva
- Département Psychiatrie et Neurosciences, Faculté de Médecine, Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Giuseppe Biagini
- Laboratory of Experimental Epileptology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Department of Neurosciences, NOCSAE Hospital, Modena, Italy
| |
Collapse
|
28
|
Meinhardt U, Witassek F, Petrò R, Fritz C, Eiholzer U. Strength training and physical activity in boys: a randomized trial. Pediatrics 2013; 132:1105-11. [PMID: 24190687 DOI: 10.1542/peds.2013-1343] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND In developed societies levels of daily physical activity (PA) among school-age children are decreasing. This implies risk factors for cardiovascular and metabolic diseases. Specific strategies to improve levels of PA are needed. In prepubertal boys there is evidence that strength training increases spontaneous PA outside of training. METHODS A total of 102 schoolchildren (age 10-14 years) in Switzerland were randomly assigned to physical education classes or to participate twice weekly at a guided strength training program for 19 weeks. Spontaneous PA energy expenditure (PAEE; 3axial accelerometry for 7 days), leg and arm strength, and body composition (dual energy radiograph absorptiometry) were measured at baseline, after 19 weeks of training intervention, and after 3 months of washout. RESULTS There were no significant differences between the groups at baseline. In the intervention group, PAEE increased by 10% from baseline to end of training in boys (P = .02), but not in girls. Leg and arm strength were increased owing to training intervention in both boys and girls. All other variables were unchanged. Baseline PAEE was significantly negatively correlated with changes of PAEE. CONCLUSIONS Targeted strength training significantly increases daily spontaneous PA behavior in boys. The less active children showed the greatest increase in spontaneous PAEE. Girls showed a similar increase in strength, but not in spontaneous PAEE. This may be explained by their earlier pubertal development. Strength training may be a promising strategy in schools to counteract decreasing levels of PA.
Collapse
Affiliation(s)
- Udo Meinhardt
- Head of the Center for Pediatric Endocrinology Zurich, Moehrlistrasse 69, CH-8006 Zurich, Switzerland.
| | | | | | | | | |
Collapse
|
29
|
Gao S, Serra D, Keung W, Hegardt FG, Lopaschuk GD. Important role of ventromedial hypothalamic carnitine palmitoyltransferase-1a in the control of food intake. Am J Physiol Endocrinol Metab 2013; 305:E336-47. [PMID: 23736540 DOI: 10.1152/ajpendo.00168.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Carnitine palmitoyltransferase-1 (CPT-1) liver isoform, or CPT-1a, is implicated in CNS control of food intake. However, the exact brain nucleus site(s) in mediating this action of CPT-1a has not been identified. In this report, we assess the role of CPT-1a in hypothalamic ventromedial nucleus (VMN). We stereotaxically injected an adenoviral vector containing CPT-1a coding sequence into the VMN of rats to induce overexpression and activation of CPT-1a. The VMN-selective activation of CPT-1a induced an orexigenic effect, suggesting CPT-1a in the VMN is involved in the central control of feeding. Intracerebroventricular administration of etomoxir, a CPT-1 inhibitor, decreases food intake. Importantly, in the animals with VMN overexpression of a CPT-1a mutant that antagonizes the CPT-1 inhibition by etomoxir, the anorectic response to etomoxir was attenuated. This suggests that VMN is involved in mediating the anorectic effect of central inhibition of CPT-1a. In contrast, arcuate nucleus (Arc) overexpression of the mutant did not alter etomoxir-induced inhibition of food intake, suggesting that Arc CPT-1a does not play significant roles in this anorectic action. Furthermore, in the VMN, CPT-1a appears to act downstream of hypothalamic malonyl-CoA action of feeding. Finally, we show that in the VMN CPT-1 activity was altered in concert with fasting and refeeding states, supporting a physiological role of CPT-1a in mediating the control of feeding. All together, CPT-1a in the hypothalamic VMN appears to play an important role in central control of food intake. VMN-selective modulation of CPT-1a activity may therefore be a promising strategy in controlling food intake and maintaining normal body weight.
Collapse
Affiliation(s)
- Su Gao
- Department of Pediatrics, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | | | |
Collapse
|
30
|
Reed JL, Chaput JP, Tremblay A, Doucet É. The maintenance of energy balance is compromised after weight loss. Can J Diabetes 2013; 37:121-7. [PMID: 24070803 DOI: 10.1016/j.jcjd.2013.03.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/04/2013] [Accepted: 03/04/2013] [Indexed: 10/26/2022]
Abstract
Available literature reveals that of the majority of individuals who are able to lose weight, only a small number are able to maintain their weight loss over time. Effective weight maintenance strategies after weight loss are illusive, which is most likely the result of a number of yet poorly understood factors. In fact, both appetite and energy expenditure are profoundly altered in response to reductions in body energy reserves. Weight reduction leads to decreased energy needs, but to an augmented drive to eat, thus compromising the maintenance of energy balance in the weight-reduced state by widening the theoretical gap between the 2 components of energy balance. This review first provides a summary of the factors related to the control of feeding and energy expenditure during weight stability. More specifically related to the topic of this review, the bulk of the literature presented depicts the post weight-loss control of appetite and energy expenditure. The integration of the literature presented in this paper reveals that body weight loss seems to orchestrate a coordinated response to resist further energy depletion, that would seem to create a state of increased vulnerability of weight regain. It is argued that these changes are largely responsible for the more than apparent difficulty in maintaining weight maintenance after weight loss.
Collapse
Affiliation(s)
- Jennifer L Reed
- School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada; Minto Prevention and Rehabilitation Centre, University of Ottawa Heart Institute, Canada.
| | | | | | | |
Collapse
|