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Tanday N, Lafferty RA, Flatt PR, Irwin N. Beneficial metabolic effects of recurrent periods of beta-cell rest and stimulation using stable neuropeptide Y1 and glucagon-like peptide-1 receptor agonists. Diabetes Obes Metab 2022; 24:2353-2363. [PMID: 35848461 PMCID: PMC9804730 DOI: 10.1111/dom.14821] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/01/2022] [Accepted: 07/12/2022] [Indexed: 01/09/2023]
Abstract
AIM To examine whether sequential administration of (d-Arg35 )-sea lamprey peptide tyrosine tyrosine (1-36) (SL-PYY) and the glucagon-like peptide-1 (GLP-1) mimetic, liraglutide, has beneficial effects in diabetes. METHODS SL-PYY is an enzymatically stable neuropeptide Y1 receptor (NPY1R) agonist known to induce pancreatic beta-cell rest and improve overall beta-cell health. We employed SL-PYY and liraglutide to induce appropriate recurrent periods of beta-cell rest and stimulation, to assess therapeutic benefits in high fat fed (HFF) mice with streptozotocin (STZ)-induced insulin deficiency, namely HFF-STZ mice. RESULTS Previous studies confirm that, at a dose of 0.25 nmol/kg, liraglutide exerts bioactivity over an 8-12 hour period in mice. Initial pharmacokinetic analysis revealed that 75 nmol/kg SL-PYY yielded a similar plasma drug time profile. When SL-PYY (75 nmol/kg) and liraglutide (0.25 nmol/kg) were administered sequentially at 08:00 AM and 08:00 PM, respectively, to HFF-STZ mice for 28 days, reductions in energy intake, body weight, circulating glucose, insulin and glucagon were noted. Similarly positive, but slightly less striking, effects were also apparent with twice-daily liraglutide-only therapy. The sequential SL-PYY and liraglutide treatment also improved insulin sensitivity and glucose-induced insulin secretory responses, which was not apparent with liraglutide treatment, although benefits on glucose tolerance were mild. Interestingly, combined therapy also elevated pancreatic insulin, decreased pancreatic glucagon and enhanced the plasma insulin/glucagon ratio compared with liraglutide alone. This was not associated with an enhancement of beneficial changes in islet cell areas, proliferation or apoptosis compared with liraglutide alone, but the numbers of centrally stained glucagon-positive islet cells were reduced by sequential combination therapy. CONCLUSION These data show that NPY1R-induced intervals of beta-cell rest, combined with GLP-1R-stimulated periods of beta-cell stimulation, should be further evaluated as an effective treatment option for obesity-driven forms of diabetes.
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Affiliation(s)
- Neil Tanday
- Biomedical Sciences Research InstituteCentre for Diabetes, Ulster UniversityColeraineNorthern Ireland
| | - Ryan A. Lafferty
- Biomedical Sciences Research InstituteCentre for Diabetes, Ulster UniversityColeraineNorthern Ireland
| | - Peter R. Flatt
- Biomedical Sciences Research InstituteCentre for Diabetes, Ulster UniversityColeraineNorthern Ireland
| | - Nigel Irwin
- Biomedical Sciences Research InstituteCentre for Diabetes, Ulster UniversityColeraineNorthern Ireland
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Greene ES, Abdelli N, Dridi JS, Dridi S. Avian Neuropeptide Y: Beyond Feed Intake Regulation. Vet Sci 2022; 9:171. [PMID: 35448669 PMCID: PMC9028514 DOI: 10.3390/vetsci9040171] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
Neuropeptide Y (NPY) is one of the most abundant and ubiquitously expressed neuropeptides in both the central and peripheral nervous systems, and its regulatory effects on feed intake and appetite- have been extensively studied in a wide variety of animals, including mammalian and non-mammalian species. Indeed, NPY has been shown to be involved in the regulation of feed intake and energy homeostasis by exerting stimulatory effects on appetite and feeding behavior in several species including chickens, rabbits, rats and mouse. More recent studies have shown that this neuropeptide and its receptors are expressed in various peripheral tissues, including the thyroid, heart, spleen, adrenal glands, white adipose tissue, muscle and bone. Although well researched centrally, studies investigating the distribution and function of peripherally expressed NPY in avian (non-mammalian vertebrates) species are very limited. Thus, peripherally expressed NPY merits more consideration and further in-depth exploration to fully elucidate its functions, especially in non-mammalian species. The aim of the current review is to provide an integrated synopsis of both centrally and peripherally expressed NPY, with a special focus on the distribution and function of the latter.
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Affiliation(s)
- Elizabeth S. Greene
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
| | - Nedra Abdelli
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
- Animal Nutrition and Welfare Service, Department of Animal and Food Sciences, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Jalila S. Dridi
- École Universitaire de Kinésithérapie, Université d’Orléans, Rue de Chartres, 45100 Orleans, France;
| | - Sami Dridi
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
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Uhl M, Schmeisser MJ, Schumann S. The Sexual Dimorphic Synapse: From Spine Density to Molecular Composition. Front Mol Neurosci 2022; 15:818390. [PMID: 35250477 PMCID: PMC8894598 DOI: 10.3389/fnmol.2022.818390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/20/2022] [Indexed: 11/13/2022] Open
Abstract
A synaptic sexual dimorphism is relevant in the context of multiple neurodevelopmental, neurodegenerative, and neuropsychiatric disorders. Many of these disorders show a different prevalence and progression in woman and man. A similar variance is also present in corresponding animal models. To understand and characterize this dimorphism in pathologies it is important to first understand sex differences in unaffected individuals. Therefore, sexual differences have been studied since 1788, first focusing on brain weight, size, and volume. But as these measures are not directly related to brain function, the investigation of sexual dimorphism also expanded to other organizational levels of the brain. This review is focused on sexual dimorphism at the synaptic level, as these specialized structures are the smallest functional units of the brain, determining cell communication, connectivity, and plasticity. Multiple differences between males and females can be found on the levels of spine density, synaptic morphology, and molecular synapse composition. These differences support the importance of sex-disaggregated data. The specificity of changes to a particular brain region or circuit might support the idea of a mosaic brain, in which each tile individually lies on a continuum from masculinization to feminization. Moreover, synapses can be seen as the smallest tiles of the mosaic determining the classification of larger areas.
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Affiliation(s)
- Mara Uhl
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Focus Program Translational Neurosciences, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Michael J. Schmeisser
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Focus Program Translational Neurosciences, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- *Correspondence: Michael J. Schmeisser,
| | - Sven Schumann
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Sven Schumann,
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Badiger KB, Khatavi SY, Hiremath PB, Kamanna K. Agro-waste sourced catalyst as an eco-friendly and sustainable approach for Knoevenagel condensation reaction. CURRENT ORGANOCATALYSIS 2021. [DOI: 10.2174/2213337209666211222145453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
The present work describes an eco-friendly and sustainable approach for the Knoevenagel condensation of an aromatic aldehyde with ethyl cyanoacetate, and salicylaldehyde with Meldrum acid for the synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin (2-oxo-2H-1-benzopyran) derivatives, respectively. The reaction performed under greener catalytic media Water Extract of Watermelon Fruit Peel Ash (WEWFPA) is an eco-friendly protocol derived from the agro-waste feedstock. Various protocols have been reported for the synthesis of Knoevenagel condensation reaction using a hazardous catalyst or/and solvent found toxic to the environment, reaction time longer, poor yield, and required purification of the final product. The present method provides several added advantages of being completely greener, economic, giving high yield, inexpensive catalyst, and the final product isolated in pure form with good yield.
Objective:
The objective of the study was to develop a green methodology for the synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives.
Results:
The agro-waste based catalyst developed avoids the use of external inorganic/organic base, additives, and solvent-free synthesis of Knoevenagel condensation of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives under rt and microwave irradiation, respectively described. The microwave irradiation condition requires less time for the completion of the reaction and also gave better yield isolation
Methods:
We have demonstrated WEWFPA as a greener homogenous agro-waste is employed under rt stirring and microwave irradiation for the economic synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives. The developed method was found robust, non-hazardous and solvent-free with simple work-up gave target product.
Conclusion:
In conclusion, we have established an efficient, simple, agro-waste based catalytic approach for the synthesis of ethylbenzylidenecyanoacetate and 3-carboxy coumarin derivatives employing WEWFPA as an efficient catalyst under rt stirring and microwave synthesis, respectively. The method is a greener, economical and eco-friendly approach for the synthesis of Knoevenagel condensation products. The advantages of the present approach are solvent-free, no external metal, chemical base free, short reaction time and isolated product in good to excellent yields. The catalyst is agro-waste derived, which has abundant in natural sources, thus making the present approach a greener one.
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Affiliation(s)
- Krishnappa B Badiger
- Peptide and Medicinal Chemistry Research Laboratory, Department of Chemistry, Rani Channamma University, P-B, NH-4, Belagavi 591 156, India
| | - Santosh Y Khatavi
- Peptide and Medicinal Chemistry Research Laboratory, Department of Chemistry, Rani Channamma University, P-B, NH-4, Belagavi 591 156, India
| | - Prashant B Hiremath
- Peptide and Medicinal Chemistry Research Laboratory, Department of Chemistry, Rani Channamma University, P-B, NH-4, Belagavi 591 156, India
| | - Kantharaju Kamanna
- Peptide and Medicinal Chemistry Research Laboratory, Department of Chemistry, Rani Channamma University, P-B, NH-4, Belagavi 591 156, India
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Hiremath PB, Kamanna K. Ultrasound-Promoted Sustainable Synthesis and Antimicrobial Evaluation of 2-Aryl Benzimidazoles Catalyzed by BPAE at Room Temperature. CURRENT ORGANOCATALYSIS 2021. [DOI: 10.2174/2213337208666210212122027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Present-day chemists are more interested in developing and using green
chemistry protocol for various organic transformations, which employ natural feedstock extracts,
and solvent-free, and greener catalysts; they are well known for their non-hazardous nature and
have replaced many organic and inorganic based catalysts. In literature, the reported homogenous
catalytic approaches have been employed for various bioactive heterocycle syntheses, which follow
the green chemistry principle established for various organic transformations catalyzed by
WERSA, BFE, WEPPA, WEMFSA, WEMPA, and Eichhorniacrassipes. Among them, 2-aryl benzimidazole
derivatives have emerged as prominent molecules with a wide variety of applications in
biological and material science.
Methods:
The agro-waste sourced from the banana peel is utilized for the preparation of BPAE catalyst,
which is employed for the synthesis of 2-aryl benzimidazole derivatives under ultrasound
waves at room temperature.
Results:
Here, 2-Aryl benzimidazoles synthesized through the reaction of a substituted o-phenylene
diamine with substituted benzoyl chloride catalyzed by BPAE under ultrasound waves at
room temperature are described. Furthermore, catalyst BPAE is characterized by flame emission
spectrometry, SEM-EDX, and XRD techniques.
Conclusion:
The present work established an eco-friendly, sustainable and novel approach for the
synthesis of 2-aryl benzimidazoles using natural feedstock BPAE. The major merits of BPAE include
its use as an agro-waste-derived catalyst. It is also highly abundant, inexpensive, yields faster
reactions, has a simple workup, and does not require the use of column chromatography.
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Affiliation(s)
- Prashant B. Hiremath
- Department of Chemistry, Peptide and Medicinal Chemistry Research Laboratory, Rani Channamma University, P-B, NH-4, Belagavi-591156, Karnataka, India
| | - Kantharaju Kamanna
- Department of Chemistry, Peptide and Medicinal Chemistry Research Laboratory, Rani Channamma University, P-B, NH-4, Belagavi-591156, Karnataka, India
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Lactobacillus plantarum Reduces Low-Grade Inflammation and Glucose Levels in a Mouse Model of Chronic Stress and Diabetes. Infect Immun 2021; 89:e0061520. [PMID: 34001561 DOI: 10.1128/iai.00615-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
This study aimed to examine the effects of Lactobacillus plantarum, a lactic acid bacteria strain isolated from kimchi, on the development of low-grade inflammation and type 2 diabetes mellitus (T2DM) exacerbated by chronic stress. C57BL/6 mice were fed either a high-fat diet (HFD) and randomized into an HFD group or a group that was fed an HFD and subjected to chronic cold exposure-related stress (HFDS), or mice were fed a normal diet (ND) and randomized into an ND group or a group that was fed an ND and subjected to chronic cold exposure-related stress (NDS). Lactobacillus plantarum LRCC5310 (108, 1010 CFU) and LRCC5314 (108, 1010 CFU) as well as L. gasseri BNR17 (108 CFU), as a positive control, were administered orally twice every day to all the mice for 12 weeks. The expression of Glut4 and adiponectin, main glucose transporter-related genes, was upregulated in the LRCC5310- and LRCC5314-treated groups. Levels of serum proinflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin-6 [IL-6]) and of mRNAs of proinflammatory genes (Tnf-α, Il-6, Ccl2, leptin) were elevated in HFDS mice. The expression of proinflammatory genes was downregulated in LRCC5310- and LRCC5314-treated groups; this was not the case for Tnf-α expression in HFDS mice. Levels of serum corticosterone and mRNA levels of stress-related genes (Npy, Y2r) were decreased in lactic acid bacteria (LAB)-fed groups, with only LRCC5314 downregulating Npy expression in HFDS mice. These results suggest that the LAB strains can normalize the expression of metabolic genes, inhibit inflammatory responses, and suppress stress in HFDS mice.
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Yuan D, Gao Y, Zhang X, Wang B, Chen H, Wu Y, Chen D, Wang Z, Li Z. NPY and NPY receptors in the central control of feeding and interactions with CART and MC4R in Siberian sturgeon. Gen Comp Endocrinol 2019; 284:113239. [PMID: 31394086 DOI: 10.1016/j.ygcen.2019.113239] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 07/25/2019] [Accepted: 08/04/2019] [Indexed: 01/08/2023]
Abstract
Neuropeptide Y (NPY) is the most powerful central neuropeptide implicated in feeding regulation via its receptors. Understanding the role of NPY system is critical to elucidate animal feeding regulation. Unlike mammal, the possible mechanisms of NPY system in the food intake of teleost fish are mostly unknown. Therefore, we investigated the regulatory mechanism of NPY and NPY receptors in Siberian sturgeon. In this study, we cloned the cDNA encoding NPY, and assessed the effects of different energy status on npy mRNAs abundance. The expression of npy was decreased in the brain after feeding 1 and 3 h. Besides, the expression of npy was increased after fasting within 15 days, while exhibiting significant decrease after refeeding. In order to further characterize the role of NPY receptor in fish, we performed acute intraperitoneal (i.p.) injection of NPY Y1 and Y2 receptor agonists, which is [Leu 31, Pro 34] NPY and NPY13-36 respectively. The results showed that the food intake of Siberian sturgeon was increased within 30 mins after injection of both Y1 and Y2 receptor agonist. To explore the relationship between NPY, NPY receptors and another appetite peptides, we examined the level of npy, cocaine- and amphetamine-regulated transcript (cart) and melanocortin-4 receptor (mc4r) by injected Y1 and Y2 receptor agonist. The results suggested that cart expression was regulated by NPY which acts on Y1 receptor or Y2 receptor. While mc4r expression just was mediated by NPY and Y1 receptor.
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Affiliation(s)
- Dengyue Yuan
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China; Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Science, Southwest University, Chongqing 400715, China
| | - Yundi Gao
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Xin Zhang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Bin Wang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Hu Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Yuanbing Wu
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Defang Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Zhijian Wang
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Science, Southwest University, Chongqing 400715, China
| | - Zhiqiong Li
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China.
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Zhu P, Zhang ZH, Huang XF, Shi YC, Khandekar N, Yang HQ, Liang SY, Song ZY, Lin S. Cold exposure promotes obesity and impairs glucose homeostasis in mice subjected to a high‑fat diet. Mol Med Rep 2018; 18:3923-3931. [PMID: 30106124 PMCID: PMC6131648 DOI: 10.3892/mmr.2018.9382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/08/2018] [Indexed: 11/06/2022] Open
Abstract
Cold exposure is considered to be a form of stress and has various adverse effects on the body. The present study aimed to investigate the effects of chronic daily cold exposure on food intake, body weight, serum glucose levels and the central energy balance regulatory pathway in mice fed with a high‑fat diet (HFD). C57BL/6 mice were divided into two groups, which were fed with a standard chow or with a HFD. Half of the mice in each group were exposed to ice‑cold water for 1 h/day for 7 weeks, while the controls were exposed to room temperature. Chronic daily cold exposure significantly increased energy intake, body weight and serum glucose levels in HFD‑fed mice compared with the control group. In addition, 1 h after the final cold exposure, c‑fos immunoreactivity was significantly increased in the central amygdala of HFD‑fed mice compared with HFD‑fed mice without cold exposure, indicating neuronal activation in this brain region. Notably, 61% of these c‑fos neurons co‑expressed the neuropeptide Y (NPY), and the orexigenic peptide levels were significantly increased in the central amygdala of cold‑exposed mice compared with control mice. Notably, cold exposure significantly decreased the anorexigenic brain‑derived neurotropic factor (BDNF) messenger RNA (mRNA) levels in the ventromedial hypothalamic nucleus and increased growth hormone releasing hormone (GHRH) mRNA in the paraventricular nucleus. NPY‑ergic neurons in the central amygdala were activated by chronic cold exposure in mice on HFD via neuronal pathways to decrease BDNF and increase GHRH mRNA expression, possibly contributing to the development of obesity and impairment of glucose homeostasis.
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Affiliation(s)
- Ping Zhu
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Zhi-Hui Zhang
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Xu-Feng Huang
- Illawarra Health and Medical Research Institute and School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Yan-Chuan Shi
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
| | - Neeta Khandekar
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
| | - He-Qin Yang
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Shi-Yu Liang
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Zhi-Yuan Song
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Shu Lin
- Department of Cardiology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
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Thomas MA, Xue B. Mechanisms for AgRP neuron-mediated regulation of appetitive behaviors in rodents. Physiol Behav 2017; 190:34-42. [PMID: 29031550 DOI: 10.1016/j.physbeh.2017.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 08/29/2017] [Accepted: 10/06/2017] [Indexed: 12/19/2022]
Abstract
The obesity epidemic is a major health and economic burden facing both developed and developing countries worldwide. Interrogation of the central and peripheral mechanisms regulating ingestive behaviors have primarily focused on food intake, and in the process uncovered a detailed neuroanatomical framework controlling this behavior. However, these studies have largely ignored the behaviors that bring animals, including humans, in contact with food. It is therefore useful to dichotomize ingestive behaviors as appetitive (motivation to find and store food) and consummatory (consumption of food once found), and utilize an animal model that naturally displays these behaviors. Recent advances in genetics have facilitated the identification of several neuronal populations critical for regulating ingestive behaviors in mice, and novel functions of these neurons and neuropeptides in regulating appetitive behaviors in Siberian hamsters, a natural model of food foraging and food hoarding, have been identified. To this end, hypothalamic agouti-related protein/neuropeptide Y expressing neurons (AgRP neurons) have emerged as a critical regulator of ingestive behaviors. Recent studies by Dr. Timothy Bartness and others have identified several discrete mechanisms through which peripheral endocrine signals regulate AgRP neurons to control food foraging, food hoarding, and food intake. We review here recent advances in our understanding of the neuroendocrine control of ingestive behaviors in Siberian hamsters and other laboratory rodents, and identify novel mechanisms through which AgRP neurons mediate appetitive and consummatory behaviors.
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Affiliation(s)
- M Alex Thomas
- Department of Biology, Georgia State University, Atlanta, GA 30302, USA; Center for Obesity Reversal, Georgia State University, Atlanta, GA 30302, USA
| | - Bingzhong Xue
- Department of Biology, Georgia State University, Atlanta, GA 30302, USA; Center for Obesity Reversal, Georgia State University, Atlanta, GA 30302, USA; Neuroscience Institute, Georgia State University, Atlanta, GA 30302, USA.
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Kokavec A. Migraine: A disorder of metabolism? Med Hypotheses 2016; 97:117-130. [PMID: 27876120 DOI: 10.1016/j.mehy.2016.10.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/23/2016] [Accepted: 10/31/2016] [Indexed: 02/08/2023]
Abstract
The treatment and prevention of migraine within the last decade has become largely pharmacological. While there is little doubt that the advent of drugs (e.g. triptans) has helped many migraine sufferers to lead a normal life, there is still little knowledge with respect to the factors responsible for precipitating a migraine attack. Evidence from biochemical and behavioural studies from a number of disciplines is integrated to put forward the proposal that migraine is part of a cascade of events, which together act to protect the organism when confronted by a metabolic challenge.
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Affiliation(s)
- Anna Kokavec
- University of New England, School of Health, Armidale, NSW 2350, United States.
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Stanley BG, Gillard ER. Hypothalamic Neuropeptide Y and the Regulation of Eating Behavior and Body Weight. CURRENT DIRECTIONS IN PSYCHOLOGICAL SCIENCE 2016. [DOI: 10.1111/1467-8721.ep10769834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B. Glenn Stanley
- An Associate Professor in the Departments of Psychology and Neuroscience, University of California, Riverside
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RNA sequencing reveals region-specific molecular mechanisms associated with epileptogenesis in a model of classical hippocampal sclerosis. Sci Rep 2016; 6:22416. [PMID: 26935982 PMCID: PMC4776103 DOI: 10.1038/srep22416] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/15/2016] [Indexed: 01/20/2023] Open
Abstract
We report here the first complete transcriptome analysis of the dorsal (dDG) and ventral dentate gyrus (vDG) of a rat epilepsy model presenting a hippocampal lesion with a strict resemblance to classical hippocampal sclerosis (HS). We collected the dDG and vDG by laser microdissection 15 days after electrical stimulation and performed high-throughput RNA-sequencing. There were many differentially regulated genes, some of which were specific to either of the two sub-regions in stimulated animals. Gene ontology analysis indicated an enrichment of inflammation-related processes in both sub-regions and of axonal guidance and calcium signaling processes exclusively in the vDG. There was also a differential regulation of genes encoding molecules involved in synaptic function, neural electrical activity and neuropeptides in stimulated rats. The data presented here suggests, in the time point analyzed, a remarkable interaction among several molecular components which takes place in the damaged hippocampi. Furthermore, even though similar mechanisms may function in different regions of the DG, the molecular components involved seem to be region specific.
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Khan AM. Controlling feeding behavior by chemical or gene-directed targeting in the brain: what's so spatial about our methods? Front Neurosci 2013; 7:182. [PMID: 24385950 PMCID: PMC3866545 DOI: 10.3389/fnins.2013.00182] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 09/20/2013] [Indexed: 12/26/2022] Open
Abstract
Intracranial chemical injection (ICI) methods have been used to identify the locations in the brain where feeding behavior can be controlled acutely. Scientists conducting ICI studies often document their injection site locations, thereby leaving kernels of valuable location data for others to use to further characterize feeding control circuits. Unfortunately, this rich dataset has not yet been formally contextualized with other published neuroanatomical data. In particular, axonal tracing studies have delineated several neural circuits originating in the same areas where ICI injection feeding-control sites have been documented, but it remains unclear whether these circuits participate in feeding control. Comparing injection sites with other types of location data would require careful anatomical registration between the datasets. Here, a conceptual framework is presented for how such anatomical registration efforts can be performed. For example, by using a simple atlas alignment tool, a hypothalamic locus sensitive to the orexigenic effects of neuropeptide Y (NPY) can be aligned accurately with the locations of neurons labeled by anterograde tracers or those known to express NPY receptors or feeding-related peptides. This approach can also be applied to those intracranial "gene-directed" injection (IGI) methods (e.g., site-specific recombinase methods, RNA expression or interference, optogenetics, and pharmacosynthetics) that involve viral injections to targeted neuronal populations. Spatial alignment efforts can be accelerated if location data from ICI/IGI methods are mapped to stereotaxic brain atlases to allow powerful neuroinformatics tools to overlay different types of data in the same reference space. Atlas-based mapping will be critical for community-based sharing of location data for feeding control circuits, and will accelerate our understanding of structure-function relationships in the brain for mammalian models of obesity and metabolic disorders.
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Affiliation(s)
- Arshad M. Khan
- UTEP Systems Neuroscience Laboratory, Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El PasoEl Paso, TX, USA
- Neurobiology Section, Department of Biological Sciences, University of Southern CaliforniaLos Angeles, CA, USA
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Teubner BJ, Bartness TJ. PYY(3-36) into the arcuate nucleus inhibits food deprivation-induced increases in food hoarding and intake. Peptides 2013; 47:20-8. [PMID: 23816798 PMCID: PMC3759582 DOI: 10.1016/j.peptides.2013.05.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 05/11/2013] [Accepted: 05/13/2013] [Indexed: 12/17/2022]
Abstract
Central administration of neuropeptide Y (NPY) increases food intake in laboratory rats and mice, as well as food foraging and hoarding in Siberian hamsters. The NPY-Y1 and Y5 receptors (Rs) within the hypothalamus appear sufficient to account for these increases in ingestive behaviors. Stimulation of NPY-Y2Rs in the Arcuate nucleus (Arc) has an anorexigenic effect as shown by central or peripheral administration of its natural ligand peptide YY (3-36) and pharmacological NPY-Y2R antagonism by BIIE0246 increases food intake. Both effects on food intake by NPY-Y2R agonism and antagonism are relatively short-lived lasting ∼4h. The role of NPY-Y2Rs in appetitive ingestive behaviors (food foraging/hoarding) is untested, however. Therefore, Siberians hamsters, a natural food hoarder, were housed in a semi-natural burrow/foraging system that had (a) foraging requirement (10 revolutions/pellet), no free food (true foraging group), (b) no running wheel access, free food (general malaise control) or (c) running wheel access, free food (exercise control). We microinjected BIIE0246 (antagonist) and PYY(3-36) (agonist) into the Arc to test the role of NPY-Y2Rs there on ingestive behaviors. Food foraging, hoarding, and intake were not affected by Arc BIIE0246 microinjection in fed hamsters 1, 2, 4, and 24h post injection. Stimulation of NPY-Y2Rs by PYY(3-36) inhibited food intake at 0-1 and 1-2h and food hoarding at 1-2h without causing general malaise or affecting foraging. Collectively, these results implicate a sufficiency, but not necessity, of the Arc NPY-Y2R in the inhibition of food intake and food hoarding by Siberian hamsters.
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Affiliation(s)
- Brett J.W. Teubner
- Department of Biology and Obesity Reversal Center, Georgia State University, Atlanta, GA 30302-4010 USA
| | - Timothy J. Bartness
- Department of Biology and Obesity Reversal Center, Georgia State University, Atlanta, GA 30302-4010 USA
- To whom all correspondence should be addressed. Dr. Timothy J. Bartness, Department of Biology, 24 Peachtree Center Ave. NE, Georgia State University, Atlanta, GA 30302-4010, Phone: (404) 413-5334, FAX: (404) 413-5301,
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15
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Shimizu S, Azuma M, Morimoto N, Kikuyama S, Matsuda K. Effect of neuropeptide Y on food intake in bullfrog larvae. Peptides 2013; 46:102-7. [PMID: 23756158 DOI: 10.1016/j.peptides.2013.05.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 05/30/2013] [Accepted: 05/30/2013] [Indexed: 10/26/2022]
Abstract
Neuropeptide Y (NPY) is a potent orexigenic neuropeptide implicated in appetite regulation in mammals. However, except for teleost fish such as the goldfish and zebrafish, the involvement of NPY in the regulation of feeding in non-mammalian vertebrates has not been well studied. Anuran amphibian larvae feed and grow during the pre- and pro-metamorphic stages, but, thereafter they stop feeding as the metamorphic climax approaches. Therefore, orexigenic factors seem to play important roles in pre- and pro-metamorphic larvae. We investigated the role of NPY in food intake using bullfrog larvae including pre- and pro-metamorphic stages, and examined the effect of feeding status on the expression level of the NPY transcript in the hypothalamus. NPY mRNA levels in hypothalamus specimens obtained from larvae that had been fasted for 3 days were higher than those in larvae that had been fed normally. We then investigated the effect of intracerebroventricular (ICV) administration of NPY on food intake in the larvae. Cumulative food intake was significantly increased by ICV administration of NPY (5 and 10 pmol/g body weight, BW) during a 15-min observation period. The NPY-induced orexigenic action (10 pmol/g BW) was blocked by treatment with a NPY Y1 receptor antagonist, BIBP-3226 (100 pmol/g BW). These results indicate that NPY acts as an orexigenic factor in bullfrog larvae.
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Affiliation(s)
- Shunsuke Shimizu
- Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama, Toyama 930-8555, Japan
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16
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Matsuda K, Sakashita A, Yokobori E, Azuma M. Neuroendocrine control of feeding behavior and psychomotor activity by neuropeptideY in fish. Neuropeptides 2012; 46:275-83. [PMID: 23122775 DOI: 10.1016/j.npep.2012.09.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 07/12/2012] [Accepted: 09/18/2012] [Indexed: 10/27/2022]
Abstract
Neuropeptide Y (NPY) is a neuropeptide distributed widely among vertebrates. In mammals, NPY and its related peptides such as pancreatic polypeptide and peptide YY (PYY) are distributed throughout the brain and gastrointestinal tissues, and are centrally involved in many physiological functions such as the regulation of food intake, locomotion and psychomotor activities through their receptors. With regard to non-mammalian vertebrates, there has also been intensive study aimed at the identification and functional characterization of NPY, PYY and their receptors, and recent investigations of the role of NPY have revealed that it exerts several behavioral effects in goldfish and zebrafish. Both of these species are excellent teleost fish models, in which it has been demonstrated that NPY increases food consumption as an orexigenic factor and reduces locomotor activity, as is the case in mammals. This paper reviews current knowledge of NPY derived from studies of teleost fish, as representative non-mammals, focusing particularly on the role of the NPY system, and examines its significance from a comparative viewpoint.
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Affiliation(s)
- Kouhei Matsuda
- Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama, Toyama 930-8555, Japan.
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17
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Han R, Li A, Li L, Kitlinska JB, Zukowska Z. Maternal low-protein diet up-regulates the neuropeptide Y system in visceral fat and leads to abdominal obesity and glucose intolerance in a sex- and time-specific manner. FASEB J 2012; 26:3528-36. [PMID: 22539639 DOI: 10.1096/fj.12-203943] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neuropeptide Y (NPY) mediates stress-induced obesity in adult male mice by activating its Y2 receptor (Y2R) in visceral adipose tissue (VAT). Here, we studied whether the NPY-Y2R system is also activated by maternal low-protein diet (LPD) and linked to obesity in offspring. Prenatal LPD offspring had lower birth weights compared to normal-protein diet (NPD) offspring. Female prenatal and lactation stress (PLS) offspring from mothers fed an LPD developed abdominal adiposity and glucose intolerance associated with a 5-fold up-regulation of NPY mRNA and a 6-fold up-regulation of Y2R mRNA specifically in VAT, in addition to elevated platelet-rich-plasma (PRP) NPY, compared to control females fed a high-fat diet (HFD). Conversely, PLS male offspring showed lower NPY in PRP, a 10-fold decrease of Y2R mRNA in VAT, lower adiposity, and improved glucose tolerance compared to control males. Interestingly, prenatal LPD offspring cross-fostered to control lactating mothers had completely inverse metabolic and NPY phenotypes. Taken together, these findings suggested that maternal LPD activates the VAT NPY-Y2R system and increases abdominal adiposity and glucose intolerance in a sex- and time-specific fashion, suggesting that the peripheral NPY system is a potential mediator of programming for the offspring's vulnerability to obesity and metabolic syndrome.
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Affiliation(s)
- Ruijun Han
- Department of Integrative Biology and Physiology, Stress Physiology Center, University of Minnesota, 321 Church St. SE, Minneapolis, MN 55455, USA.
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18
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Abstract
Most animals are endowed with an olfactory system that is essential for finding foods, avoiding predators, and locating mating partners. The olfactory system must encode the identity and intensity of behaviorally relevant stimuli in a dynamic environmental landscape. How is olfactory information represented? How is a large dynamic range of odor concentrations represented in the olfactory system? How is this representation modulated to meet the demands of different internal physiological states? Recent studies have found that sensory terminals are important targets for neuromodulation. The emerging evidence suggests that presynaptic inhibition scales with sensory input and thus provides a mechanism to increase dynamic range of odor representation. In addition, presynaptic facilitation could be a mechanism to alter behavioral responses in hungry animals. This review will focus on the GABA(B) (gamma-aminobutyric acid) receptor-mediated presynaptic inhibition, and neuropeptide-mediated presynaptic modulation in Drosophila.
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Affiliation(s)
- Jing W Wang
- Neurobiology Section, Division of Biological Sciences, University of California-San Diego, La Jolla, California 92093, USA.
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19
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Kamijo M, Kojima K, Maruyama K, Konno N, Motohashi E, Ikegami T, Uchiyama M, Shioda S, Ando H, Matsuda K. Neuropeptide Y in tiger puffer (Takifugu rubripes): distribution, cloning, characterization, and mRNA expression responses to prandial condition. Zoolog Sci 2012; 28:882-90. [PMID: 22132785 DOI: 10.2108/zsj.28.882] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Neuropeptide tyrosine (NPY) is a potent orexigenic neuropeptide implicated in feeding regulation in rodents. However, the involvement of NPY in feeding behavior has not well been studied in fish. Therefore, we investigated the role of NPY in food intake using a tiger puffer (Takifugu rubripes) model. We observed the distribution of NPY-like immunoreactivity in the brain. Neuronal cell bodies containing NPY were located in the telencephalon, hypothalamus, mesencephalon, and medulla oblongata, and their nerve fibers were also found throughout the brain. We cloned two cDNAs, encoding NPYa and NPYb orthologs, respectively, from the brain, and also confirmed two genes encoding these NPYs in the Takifugu genome database. We examined the distribution of these transcripts in the brain using real-time PCR. Levels of NPYa mRNA in the telencephalon, mesencephalon and hypothalamus were much higher than in the medulla oblongata and cerebellum, whereas levels of NPYb mRNA in the medulla oblongata were higher than in other regions. We also examined prandial effects on the expression level of these transcripts in the telencephalon and hypothalamus. NPYa mRNA levels in the hypothalamus, but not in the telencephalon, obtained from fish fasted for one week were higher than those in fish that had been fed normally. The level was decreased at 2 h after feeding. Levels of NPYb mRNA were not affected by prandial conditions. These results suggest that NPY is present throughout the brain, and that NPYa, but not NPYb, in the hypothalamus is involved in the feeding regulation in the tiger puffer.
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Affiliation(s)
- Motoki Kamijo
- Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan
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21
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5-(2′-Pyridyl)-2-aminothiazoles: Alkyl amino sulfonamides and sulfamides as potent NPY5 antagonists. Bioorg Med Chem Lett 2011; 21:6500-4. [DOI: 10.1016/j.bmcl.2011.08.072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 08/11/2011] [Accepted: 08/15/2011] [Indexed: 11/17/2022]
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22
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Mercer RE, Chee MJS, Colmers WF. The role of NPY in hypothalamic mediated food intake. Front Neuroendocrinol 2011; 32:398-415. [PMID: 21726573 DOI: 10.1016/j.yfrne.2011.06.001] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 05/17/2011] [Accepted: 06/13/2011] [Indexed: 12/29/2022]
Abstract
Neuropeptide Y (NPY) is a highly conserved neuropeptide with orexigenic actions in discrete hypothalamic nuclei that plays a role in regulating energy homeostasis. NPY signals via a family of high affinity receptors that mediate the widespread actions of NPY in all hypothalamic nuclei. These actions are also subject to tight, intricate regulation by numerous peripheral and central energy balance signals. The NPY system is embedded within a densely-redundant network designed to ensure stable energy homeostasis. This redundancy may underlie compensation for the loss of NPY or its receptors in germline knockouts, explaining why conventional knockouts of NPY or its receptors rarely yield a marked phenotypic change. We discuss insights into the hypothalamic role of NPY from studies of its physiological actions, responses to genetic manipulations and interactions with other energy balance signals. We conclude that numerous approaches must be employed to effectively study different aspects of NPY action.
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Affiliation(s)
- Rebecca E Mercer
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada T6G 2H7
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23
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Packiarajan M, Marzabadi MR, Desai M, Lu Y, Noble SA, Wong WC, Jubian V, Chandrasena G, Wolinsky TD, Zhong H, Walker MW, Wiborg O, Andersen K. Discovery of Lu AA33810: A highly selective and potent NPY5 antagonist with in vivo efficacy in a model of mood disorder. Bioorg Med Chem Lett 2011; 21:5436-41. [DOI: 10.1016/j.bmcl.2011.06.124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/27/2011] [Accepted: 06/29/2011] [Indexed: 10/18/2022]
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Bartness TJ, Keen-Rhinehart E, Dailey MJ, Teubner BJ. Neural and hormonal control of food hoarding. Am J Physiol Regul Integr Comp Physiol 2011; 301:R641-55. [PMID: 21653877 DOI: 10.1152/ajpregu.00137.2011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Many animals hoard food, including humans, but despite its pervasiveness, little is known about the physiological mechanisms underlying this appetitive behavior. We summarize studies of food hoarding in humans and rodents with an emphasis on mechanistic laboratory studies of species where this behavior importantly impacts their energy balance (hamsters), but include laboratory rat studies although their wild counterparts do not hoard food. The photoperiod and cold can affect food hoarding, but food availability is the most significant environmental factor affecting food hoarding. Food-deprived/restricted hamsters and humans exhibit large increases in food hoarding compared with their fed counterparts, both doing so without overeating. Some of the peripheral and central peptides involved in food intake also affect food hoarding, although many have not been tested. Ad libitum-fed hamsters given systemic injections of ghrelin, the peripheral orexigenic hormone that increases with fasting, mimics food deprivation-induced increases in food hoarding. Neuropeptide Y or agouti-related protein, brain peptides stimulated by ghrelin, given centrally to ad libitum-fed hamsters, duplicates the early and prolonged postfood deprivation increases in food hoarding, whereas central melanocortin receptor agonism tends to inhibit food deprivation and ghrelin stimulation of hoarding. Central or peripheral leptin injection or peripheral cholecystokinin-33, known satiety peptides, inhibit food hoarding. Food hoarding markedly increases with pregnancy and lactation. Because fasted and/or obese humans hoard more food in general, and more high-density/high-fat foods specifically, than nonfasted and/or nonobese humans, understanding the mechanisms underlying food hoarding could provide another target for behavioral/pharmacological approaches to curb obesity.
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Affiliation(s)
- Timothy J Bartness
- Department of Biology, Neurobiology and Behavior Program, Georgia State University, Atlanta, Georgia, USA
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25
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Lagos P, Urbanavicius J, Scorza MC, Miraballes R, Torterolo P. Depressive-like profile induced by MCH microinjections into the dorsal raphe nucleus evaluated in the forced swim test. Behav Brain Res 2011; 218:259-66. [DOI: 10.1016/j.bbr.2010.10.035] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 10/13/2010] [Accepted: 10/22/2010] [Indexed: 10/18/2022]
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26
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Hostetler ED, Sanabria-Bohórquez S, Fan H, Zeng Z, Gantert L, Williams M, Miller P, O'Malley S, Kameda M, Ando M, Sato N, Ozaki S, Tokita S, Ohta H, Williams D, Sur C, Cook JJ, Burns HD, Hargreaves R. Synthesis, characterization, and monkey positron emission tomography (PET) studies of [18F]Y1-973, a PET tracer for the neuropeptide Y Y1 receptor. Neuroimage 2010; 54:2635-42. [PMID: 21078401 DOI: 10.1016/j.neuroimage.2010.11.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 10/25/2010] [Accepted: 11/02/2010] [Indexed: 11/28/2022] Open
Abstract
Neuropeptide Y receptor subtype 1 (NPY Y1) has been implicated in appetite regulation, and antagonists of NPY Y1 are being explored as potential therapeutics for obesity. An NPY Y1 PET tracer is useful for determining the level of target engagement by NPY Y1 antagonists in preclinical and clinical studies. Here we report the synthesis and evaluation of [(18)F]Y1-973, a novel PET tracer for NPY Y1. [(18)F]Y1-973 was radiolabeled by reaction of a primary chloride with [(18)F]KF/K2.2.2 followed by deprotection with HCl. [(18)F]Y1-973 was produced with high radiochemical purity (>98%) and high specific activity (>1000 Ci/mmol). PET studies in rhesus monkey brain showed that the distribution of [(18)F]Y1-973 was consistent with the known NPY Y1 distribution; uptake was highest in the striatum and cortical regions and lowest in the pons, cerebellum nuclei, and brain stem. Blockade of [(18)F]Y1-973 uptake with NPY Y1 antagonist Y1-718 revealed a specific signal that was dose-dependently reduced in all regions of grey matter to a similarly low level of tracer uptake, indicative of an NPY Y1 specific signal. In vitro autoradiographic studies with [(18)F]Y1-973 in rhesus monkey and human brain tissue slices revealed an uptake distribution consistent with the in vivo PET studies. Highest binding density was observed in the dentate gyrus, caudate-putamen, and cortical regions; moderate binding density in the hypothalamus and thalamus; and lowest binding density in the globus pallidus and cerebellum. In vitro saturation binding studies in rhesus monkey and human caudate-putamen homogenates confirmed a similarly high B(max)/K(d) ratio for [(18)F]Y1-973, suggesting the tracer may provide a specific signal in human brain of similar magnitude to that observed in rhesus monkey. [(18)F]Y1-973 is a suitable PET tracer for imaging NPY Y1 in rhesus monkey with potential for translation to human PET studies.
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Affiliation(s)
- Eric D Hostetler
- Imaging, Merck Research Laboratories, West Point, PA 19486, USA.
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27
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Lagos P, Torterolo P, Jantos H, Monti JM. Immunoneutralization of melanin-concentrating hormone (MCH) in the dorsal raphe nucleus: effects on sleep and wakefulness. Brain Res 2010; 1369:112-8. [PMID: 21078307 DOI: 10.1016/j.brainres.2010.11.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 11/07/2010] [Indexed: 10/18/2022]
Abstract
Hypothalamic neurons that utilize melanin-concentrating hormone (MCH) as a neuromodulator exert a positive control over energy homeostasis, inducing feeding and decreasing metabolism. Recent studies have shown also that this system plays a role in the generation and/or maintenance of sleep. MCHergic neurons project to the serotonergic dorsal raphe nucleus (DR), a neuroanatomical structure involved in several functions during wakefulness (W), and in the regulation of rapid-eye movements (REM) sleep. Recently, we determined the effect of MCH microinjected into the DR on sleep variables in the rat. MCH produced a marked increment of REM sleep, whereas slow wave sleep (SWS) showed only a moderate increase. In the present study, we analyze the effect of immunoneutralization of MCH in the DR on sleep and W in the rat. Compared to the control solution, microinjections of anti-MCH antibodies (1/100 solution in 0.2 μl) induced a significant increase in REM sleep latency (31.2±7.1 vs. 84.2±24.8 min, p<0.05) and a decrease of REM sleep time (37.8±5.4 vs. 17.8±2.9 min, p<0.05) that was related to the reduction in the number of REM sleep episodes. In addition, there was an increase of total W time (49.8±4.6 vs. 72.0±5.7 min, p<0.01). Light sleep and SWS remained unchanged. The intra-DR administration of a more diluted solution of anti-MCH antibodies (1/500) or rabbit pre-immune serum did not modify neither W nor REM sleep variables. Our findings strongly suggest that MCH released in the DR facilitates the occurrence of REM sleep.
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Affiliation(s)
- Patricia Lagos
- Department of Physiology, School of Medicine, University of the Republic, Montevideo, Uruguay
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28
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Pizzi DA, Leslie CP, Mazzali A, Seri C, Biagetti M, Bentley J, Genski T, Di Fabio R, Contini S, Sabbatini FM, Zonzini L, Caberlotto L. Design, synthesis and SAR of a novel series of benzimidazoles as potent NPY Y5 antagonists. Bioorg Med Chem Lett 2010; 20:7120-3. [PMID: 20951033 DOI: 10.1016/j.bmcl.2010.09.064] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 09/09/2010] [Accepted: 09/10/2010] [Indexed: 01/03/2023]
Abstract
A novel class of benzimidazole NPY Y5 receptor antagonists was prepared exploiting a privileged spirocarbamate moiety. The structure-activity relationship of this series and efforts to achieve a profile suitable for further development and an appropriate pharmacokinetic profile in rat are described. Optimisation led to the identification of the brain penetrant, orally bioavailable Y5 antagonist 9b which significantly inhibited the food intake induced by a Y5 selective agonist with a minimal effective dose of 30mg/kg po.
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Affiliation(s)
- Domenica Antonia Pizzi
- GlaxoSmithKline, Neurosciences Centre of Excellence for Drug Discovery, Medicines Research Centre, Verona, Italy.
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29
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Leslie CP, Bentley J, Biagetti M, Contini S, Di Fabio R, Donati D, Genski T, Guery S, Mazzali A, Merlo G, Pizzi DA, Sacco F, Seri C, Tessari M, Zonzini L, Caberlotto L. Discovery and structure-activity relationship of a novel spirocarbamate series of NPY Y5 antagonists. Bioorg Med Chem Lett 2010; 20:6103-7. [PMID: 20813523 DOI: 10.1016/j.bmcl.2010.08.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 08/06/2010] [Accepted: 08/07/2010] [Indexed: 10/19/2022]
Abstract
A novel series of trans-8-aminomethyl-1-oxa-3-azaspiro[4.5]decan-2-one derivatives was identified with potent NPY Y5 antagonist activity. Optimization of the original lead furnished compounds 23p and 23u, which combine sub-nanomolar Y5 activity with metabolic stability, oral bioavailability, brain penetration and strong preclinical profile for development. Both compounds significantly inhibited the food intake induced by a Y5 selective agonist with minimal effective doses of 3mg/kg po.
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Affiliation(s)
- Colin P Leslie
- Neurosciences Centre of Excellence for Drug Discovery, GlaxoSmithKline SpA, Medicines Research Centre, Verona, Italy.
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30
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Yavropoulou MP, Yovos JG. Central Regulation of Glucose-Dependent Insulinotropic Polypeptide Secretion. VITAMINS AND HORMONES 2010; 84:185-201. [DOI: 10.1016/b978-0-12-381517-0.00006-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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31
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Effects of intracerebroventricular administration of the NPY-Y1 receptor antagonist, 1229U91, on hyperphagic and glycemic responses to acute and chronic intermediate insulin-induced hypoglycemia in female rats. ACTA ACUST UNITED AC 2010; 159:14-8. [DOI: 10.1016/j.regpep.2009.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2008] [Revised: 06/10/2009] [Accepted: 07/06/2009] [Indexed: 11/17/2022]
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32
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Salter-Venzon D, Watts AG. Site-specific attenuation of food intake but not the latency to eat after hypothalamic injections of neuropeptide Y in dehydrated-anorexic rats. Am J Physiol Regul Integr Comp Physiol 2009; 297:R1813-21. [PMID: 19741057 DOI: 10.1152/ajpregu.00116.2009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Anorexia that accompanies cellular dehydration in rats (DE-anorexia) offers a relatively simple model for investigating the functional organization of neural mechanisms that can suppress feeding during dehydration. Previous studies strongly suggest that the inputs that drive ingestive behavior control neurons in the paraventricular nucleus of the hypothalamus (PVH) and lateral hypothalamic area (LHA) remain active during DE-anorexia. Here we examine whether these two regions retain their sensitivity to neuropeptide Y (NPY). NPY is an important component in two major feeding-related inputs from the arcuate nucleus and the hindbrain. We found that intake responses to NPY injections in the LHA and PVH were suppressed in DE-anorexia, but the PVH remained less sensitive to the effects of NPY than the LHA in DE-anorexic animals. Indeed the higher dose of NPY (238 pmol) completely overcame shorter periods of DE-anorexia when injected into the LHA but not the PVH. However, the latency to eat after NPY injections remained unchanged from control animals, regardless of NPY dose, injection location, or intensity of anorexia. Furthermore, the onset and size of the strong and rapidly induced compensatory feeding that follows the return of water to DE-anorexic animals was also unaffected by any NPY injections. These data support the hypothesis that DE-anorexia develops as a consequence of the premature termination of regularly initiated meals, which perhaps involves processes that alter the sensitivity of satiety mechanisms downstream to the PVH and LHA.
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Affiliation(s)
- Dawna Salter-Venzon
- The Neuroscience Graduate Program and Department of Biological Sciences, University of Southern California College, University of Southern California, Los Angeles, California 90089-2520, USA
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Cho K, Ando M, Kobayashi K, Miyazoe H, Tsujino T, Ito S, Suzuki T, Tanaka T, Tokita S, Sato N. Design, synthesis and evaluation of a novel cyclohexanamine class of neuropeptide Y Y1 receptor antagonists. Bioorg Med Chem Lett 2009; 19:4781-5. [DOI: 10.1016/j.bmcl.2009.06.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 06/10/2009] [Accepted: 06/12/2009] [Indexed: 11/29/2022]
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Kameda M, Ando M, Nakama C, Kobayashi K, Kawamoto H, Ito S, Suzuki T, Tani T, Ozaki S, Tokita S, Sato N. Synthesis and evaluation of a series of 2,4-diaminopyridine derivatives as potential positron emission tomography tracers for neuropeptide Y Y1 receptors. Bioorg Med Chem Lett 2009; 19:5124-7. [PMID: 19640706 DOI: 10.1016/j.bmcl.2009.07.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 06/27/2009] [Accepted: 07/02/2009] [Indexed: 11/28/2022]
Abstract
A series of 2,4-diaminopyridine derivatives was synthesized and evaluated as potential candidates for neuropeptide Y (NPY) Y1 receptor positron emission tomography (PET) tracers. Derivatives bearing substitutions allowing reliable access to radiolabeling were designed, focusing on Y1 binding affinity and lipophilicity. The advanced derivatives 2n and 2o were identified as promising PET tracer candidates.
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Affiliation(s)
- Minoru Kameda
- Department of Medicinal Chemistry, Tsukuba Research Institute, Merck Research Laboratories, Banyu Pharmaceutical Co. Ltd, Okubo 3, Tsukuba, Ibaraki, Japan
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35
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Kameda M, Kobayashi K, Ito H, Miyazoe H, Tsujino T, Nakama C, Kawamoto H, Ando M, Ito S, Suzuki T, Kanno T, Tanaka T, Tahara Y, Tani T, Tanaka S, Tokita S, Sato N. Optimization of a series of 2,4-diaminopyridines as neuropeptide Y Y1 receptor antagonists with reduced hERG activity. Bioorg Med Chem Lett 2009; 19:4325-9. [PMID: 19487123 DOI: 10.1016/j.bmcl.2009.05.069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 05/19/2009] [Accepted: 05/20/2009] [Indexed: 10/20/2022]
Abstract
The synthesis and evaluation of a series of 2,4-diaminopyridine-based neuropeptide Y Y1 (NPY Y1) receptor antagonists are described. Compound 1 was previously reported by our laboratory to be a potent and selective Y1 antagonist; however, 1 was also found to have potent hERG inhibitory activity. The main focus of this communication is structure-activity relationship development aimed at eliminating the hERG activity of 1. This resulted in the identification of compound 3d as a potent and selective NPY Y1 antagonist with reduced hERG liability.
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Affiliation(s)
- Minoru Kameda
- Department of Medicinal Chemistry, Tsukuba Research Institute, Merck Research Laboratories, Banyu Pharmaceutical Co., Ltd, Okubo 3, Tsukuba, Ibaraki 300-2611, Japan
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Dailey MJ, Bartness TJ. Appetitive and consummatory ingestive behaviors stimulated by PVH and perifornical area NPY injections. Am J Physiol Regul Integr Comp Physiol 2009; 296:R877-92. [PMID: 19193934 DOI: 10.1152/ajpregu.90568.2008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Food is acquired (obtained by foraging) and frequently stored (hoarded) across animal taxa, including humans, but the physiological mechanisms underlying these behaviors are virtually unknown. We found that peptides that stimulate food intake in rats stimulate food foraging and/or hoarding more than intake in Siberian hamsters. Neuropeptide Y (NPY) is a potent orexigenic peptide that increases food foraging and hoarding (appetitive behavior) and food intake (consummatory behavior). Given that NPY injections into the hypothalamic paraventricular nucleus (PVH) or perifornical area (PFA) increase food intake by rats, it is possible that these injections may stimulate food foraging or hoarding by Siberian hamsters. We also tested whether antagonism of the NPY Y1 receptor (Y1-R), the agonism of which stimulates hoarding, would inhibit post-food-deprivation increases in foraging and hoarding. We injected one of three doses of NPY or vehicle into the PVH or PFA of animals housed in a simulated foraging-hoarding housing system and measured these behaviors at 1, 2, 4, and 24 h. A subset of animals was subsequently food deprived and then given PVH or PFA Y1-R antagonist microinjections before they were refed. NPY PVH microinjections decreased foraging but increased hoarding and food intake, whereas NPY PFA microinjections increased all three behaviors, but the greatest increase was in hoarding. Y1-R antagonist inhibited post-food-deprivation increases in hoarding when injected into the PVH and PFA and inhibited foraging when injected into the PFA. These results support the view that NPY is involved in appetitive and consummatory ingestive behaviors, but each may be controlled by different brain areas and/or NPY receptor subtypes.
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Affiliation(s)
- Megan J Dailey
- Department of Biology, Georgia State University, Atlanta, GA 30302-4010, USA
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37
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Halford JCG, Harrold JA. Neuropharmacology of human appetite expression. ACTA ACUST UNITED AC 2008; 14:158-64. [PMID: 18646016 DOI: 10.1002/ddrr.20] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The regulation of appetite relies on the integration of numerous episodic (meal) and tonic (energy storage) generated signals in energy regulatory centres within the central nervous system (CNS). These centers provide the pharmacological potential to modify human appetite (hunger and satiety) to increase or decrease caloric intake, or to normalize aberrant eating behavior. With regard to obesity, the satiety enhancing anti-obesity drug sibutramine has proved effective at reducing body weight. Additionally, the endocannabinoid CB(1) antagonist rimonabant has recently been approved for use in Europe (but not in the US). A 5-HT(2C) agonist lorcaserin is also currently undergoing large-scale clinical trials, but the effect of the drug on human appetite is unknown as yet. Appetite enhancing drugs such as magestrol acetate and dronabiol are currently used to promote weight gain. Finally, sibutramine, selective serotonergic reuptake inhibitors such as fluoxetine and some anti-epileptic drugs have all been used to normalise aberrant eating behaviour. All these drugs act by modifying the expression of human appetite. An assessment of a drug's effects on caloric intake and feelings of hunger and satiety is necessary before they can be considered for clinical use.
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Affiliation(s)
- Jason C G Halford
- Kissileff Laboratory for the Study of Human Ingestive Behaviour, School of Psychology, University of Liverpool, Liverpool, United Kingdom.
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Yavropoulou MP, Kotsa K, Kesisoglou I, Anastasiou O, Yovos JG. Intracerebroventricular infusion of neuropeptide Y increases glucose dependent-insulinotropic peptide secretion in the fasting conscious dog. Peptides 2008; 29:2281-5. [PMID: 18848851 DOI: 10.1016/j.peptides.2008.08.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 08/22/2008] [Accepted: 08/28/2008] [Indexed: 12/01/2022]
Abstract
The rapid increase of incretins glucose-dependent insulinotropic peptide (GIP) and glucagon like peptide-1 (GLP-1), within 5-15 min, after food ingestion, suggests that a neural mechanism might be involved in the regulation of their secretion. The aim of this study is to determine whether intracerebroventricular (i.c.v) administration of neuropeptide Y (NPY), a widely distributed neurotransmmiter, can mediate this neural regulation of GIP secretion after food consumption. Six healthy mongrel dogs were utilized for this study. A prototype epicranial apparatus was placed surgically, allowing easy and exact localization of the third ventricle for infusions or sampling. Simultaneous blood sampling was obtained from cannulation of a hind limb vein. Plasma insulin, and GIP concentrations were measured after i.c.v infusion of 5, 10 and 25 microg of NPY dissolved in 0.5 ml of artificial cerebrospinal fluid (a CSF). The secretion of GIP and insulin were increased after the injection of NPY in a different pattern. Our data indicate that NPY might be involved in a possible neural control mechanism of GIP secretion after food consumption.
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Affiliation(s)
- Maria P Yavropoulou
- Division of Endocrinology and Metabolism, Aristotle University of Thessaloniki, 1 S. Kyriakidi Street, AHEPA University Hospital, 54636 Thessaloniki, Greece.
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Ogino Y, Ohtake N, Nagae Y, Matsuda K, Moriya M, Suga T, Ishikawa M, Kanesaka M, Mitobe Y, Ito J, Kanno T, Ishihara A, Iwaasa H, Ohe T, Kanatani A, Fukami T. Design, syntheses, and structure–activity relationships of novel NPY Y5 receptor antagonists: 2-{3-Oxospiro[isobenzofuran-1(3H),4′-piperidin]-1′-yl}benzimidazole derivatives. Bioorg Med Chem Lett 2008; 18:5010-4. [DOI: 10.1016/j.bmcl.2008.08.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 07/15/2008] [Accepted: 08/06/2008] [Indexed: 10/21/2022]
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Yeh SS, Blackwood K, Schuster MW. The cytokine basis of cachexia and its treatment: are they ready for prime time? J Am Med Dir Assoc 2008; 9:219-36. [PMID: 18457797 DOI: 10.1016/j.jamda.2008.01.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Accepted: 01/04/2008] [Indexed: 01/14/2023]
Abstract
Cachexia is a hypercatabolic condition that is often associated with the terminal stages of many diseases, in which the patient's resting metabolic rate is high and loss of muscle and fat tissue mass occur at an alarming rate. The patient also usually has concurrent anorexia, amplifying the wasting syndrome that is cachexia. The greater the extent of cachexia (regardless of underlying disease), the worse the prognosis. Efforts to treat cachexia over the years have fallen short of satisfactorily reversing the wasting syndrome. This article reviews the pathophysiology of cachexia, enumerating the different pro-inflammatory cytokines that contribute to the syndrome and attempting to illustrate their interwoven pathways. We also review the different treatments that have been explored, as well as the recent literature addressing the use of anti-cytokine therapy to treat cachexia.
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41
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Pinilla L, Fernández-Fernández R, Roa J, Castellano JM, Tena-Sempere M, Aguilar E. Selective role of neuropeptide Y receptor subtype Y2 in the control of gonadotropin secretion in the rat. Am J Physiol Endocrinol Metab 2007; 293:E1385-92. [PMID: 17785504 DOI: 10.1152/ajpendo.00274.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Different signals with key roles in energy homeostasis regulate the reproductive axis. These include neuropeptide Y and polypeptide YY(3-36), whose type Y(2) receptor is the most abundant of this family in the brain. We evaluated herein the putative roles of Y(2) receptors in the control of gonadotropin secretion by means of central administration of PYY(13-36) (agonist of Y(2) receptors) and BIIE 0246 (antagonist of Y(2) receptors) to intact and orchidectomized male rats. In addition, the ability of PYY(13-36) to elicit GnRH and gonadotropin secretion in vitro and the impact of fasting on LH responses to PYY(13-36) in vivo were also monitored. Central administration of PYY(13-36) significantly decreased the circulating levels of both gonadotropins, an effect that was observed in prepubertal and adult rats. Yet a dual action of Y(2) receptors in the control of male gonadotropic axis was evidenced as their activation induced 1) stimulation of gonadotropin responses to GnRH at the pituitary but 2) inhibition of GnRH secretion at the hypothalamus. Antagonization of Y(2) receptors failed to modify basal LH secretion in intact males either after being fed ad libitum or after being fasted. In contrast, their central blockade in orchidectomized rats evoked a significant increase in circulating LH and FSH level, suggesting the constitutive activation of Y(2) receptor in such stimulated conditions. In summary, our data evidence a complex mode of action of Y(2) receptors in the control of gonadotropic axis, with stimulatory and inhibitory actions at different levels of the system that are sensitive to the gonadal status.
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Affiliation(s)
- L Pinilla
- Physiology Section, Department of Cell Biology, Physiology, and Immunology, Faculty of Medicine, University of Córdoba, Avda Menéndez Pidal s/n, 14004, Córdoba, Spain
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42
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Abstract
Obesity is a serious public health problem throughout the world, affecting both developed societies and developing countries. The central nervous system has developed a meticulously interconnected circuitry in order to keep us fed and in an adequate nutritional state. One of these consequences is that an energy-dense environment favors the development of obesity. Neuropeptide Y (NPY) is one of the most abundant and widely distributed peptides in the central nervous system of both rodents and humans and has been implicated in a variety of physiological actions. Within the hypothalamus, NPY plays an essential role in the control of food intake and body weight. Centrally administered NPY causes robust increases in food intake and body weight and, with chronic administration, can eventually produce obesity. NPY activates a population of at least six G protein-coupled Y receptors. NPY analogs exhibit varying degrees of affinity and specificity for these Y receptors. There has been renewed speculation that ligands for Y receptors may be of benefit for the treatment of obesity. This review highlights the therapeutic potential of Y(1), Y(2), Y(4), and Y(5) receptor agonists and antagonists as additional intervention to treat human obesity.
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Affiliation(s)
- M M Kamiji
- Department of Gastroenterology, Faculty of Medicine, University of Sao Paulo, Ribeirão Preto Campus 14048-900, Ribeirão Preto-SP, Brazil
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43
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Dumont Y, Moyse E, Fournier A, Quirion R. Distribution of Peripherally Injected Peptide YY ([125I] PYY (3–36)) and Pancreatic Polypeptide ([125I] hPP) in the CNS: Enrichment in the Area Postrema. J Mol Neurosci 2007; 33:294-304. [DOI: 10.1007/s12031-007-9007-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Accepted: 08/23/2007] [Indexed: 12/13/2022]
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Gehlert DR, Schober DA, Morin M, Berglund MM. Co-expression of neuropeptide Y Y1 and Y5 receptors results in heterodimerization and altered functional properties. Biochem Pharmacol 2007; 74:1652-64. [PMID: 17897631 DOI: 10.1016/j.bcp.2007.08.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Revised: 08/09/2007] [Accepted: 08/10/2007] [Indexed: 12/01/2022]
Abstract
Centrally administered neuropeptide Y (NPY) produces anxiolytic and orexigenic effects by interacting with Y1 and Y5 receptors that are colocalized in many brain regions. Therefore, we tested the hypothesis that co-expression of Y1 and Y5 receptors results in heterodimerization, altered pharmacological properties and altered desensitization. To accomplish this, the carboxyl-termini of Y1 and Y5 receptors were fused with Renilla luciferase and green fluorescent protein and the proximity of the tagged receptors assessed using bioluminescent resonance energy transfer. Under basal conditions, cotransfection of tagged Y1 receptor and Y5 produced a substantial dimerization signal that was unaffected by the endogenous, nonselective agonists, NPY and peptide YY (PYY). Selective Y5 agonists produced an increase in the dimerization signal while Y5 antagonists also produced a slight but significant increase. In the absence of agonists, selective antagonists decreased dimerization. In functional studies, Y5 agonists produced a greater inhibition of adenylyl cyclase activity in Y1/Y5 cells than cells expressing Y5 alone while NPY and PYY exhibited no difference. With PYY stimulation, the Y1 antagonist became inactive and the Y5 antagonist exhibited uncompetitive kinetics in the Y1/Y5 cell line. In confocal microscopy studies, Y1/Y5 co-expression resulted in increased Y5 signaling following PYY stimulation. Addition of both Y1 and Y5 receptor antagonists was required to significantly decrease PYY-induced internalization. Therefore, Y1/Y5 co-expression results in heterodimerization, altered agonist and antagonist responses and reduced internalization rate. These results may account for the complex pharmacology observed when assessing the responses to NPY and analogs in vivo.
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Affiliation(s)
- Donald R Gehlert
- Lilly Neuroscience, Lilly Research Laboratories, Eli Lilly and Co., Lilly Corporate Center, Indianapolis, IN 46285, United States.
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45
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Ishii T, Muranaka R, Tashiro O, Nishimura M. Chronic intracerebroventricular administration of anti-neuropeptide Y antibody stimulates starvation-induced feeding via compensatory responses in the hypothalamus. Brain Res 2007; 1144:91-100. [PMID: 17320051 DOI: 10.1016/j.brainres.2007.01.086] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Revised: 01/19/2007] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
To investigate how compensatory responses develop after the onset of inhibition of NPY signaling, we examined the effect of continuous intracerebroventricular (ICV) injection of neutralizing NPY antibodies (NPY-ab) on daily and fast-induced food intake in mice. A single ICV injection of NPY-ab reduced food intake in fasted mice. In contrast to a single injection, continuous ICV injection of NPY-ab for 13 days increased fast-induced food intake, although daily food intake was unaffected by continuous administration of NPY-ab. Immunohistochemistry indicated that the expression of NPY protein increases in the arcuate nucleus, lateral hypothalamic area, and paraventricular nucleus 7 days after onset of continuous NPY-ab infusion and remains at an elevated level, whereas the expression of the NPY Y1 receptor transiently increases in the same areas for 3 days and then gradually decreases. Similar results were obtained for the expression of NPY and NPY Y1 receptor mRNA. The mRNA level of agouti-related protein, another orexigenic neuropeptide, also increased in parallel with NPY, whereas that of pro-opiomelanocortin did not change over the 13 days of the NPY-ab administration. These results suggest that chronic central inhibition of NPY immediately activates orexigenic signaling in first-order hypothalamic neurons and that this compensatory mechanism normalizes the regulation of feeding and energy expenditure to maintain energy homeostasis. On the other hand, in mice that have acquired this compensation, fast-induced food intake further increases even after the energy deficit is corrected because of the dominant orexigenic signal.
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Affiliation(s)
- Toshiaki Ishii
- Department of Pathobiological Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro Hokkaido 080-8555, Japan.
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Sloth B, Holst JJ, Flint A, Gregersen NT, Astrup A. Effects of PYY1-36 and PYY3-36 on appetite, energy intake, energy expenditure, glucose and fat metabolism in obese and lean subjects. Am J Physiol Endocrinol Metab 2007; 292:E1062-8. [PMID: 17148749 DOI: 10.1152/ajpendo.00450.2006] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Peptide YY (PYY)(3-36) has been shown to produce dramatic reductions in energy intake (EI), but no human data exist regarding energy expenditure (EE), glucose and fat metabolism. Nothing is known regarding PYY1-36. To compare effects of PYY(1-36) and PYY(3-36) on appetite, EI, EE, insulin, glucose and free fatty acids (FFA) concentrations, 12 lean and 12 obese males participated in a blinded, randomized, crossover study with 90-min infusions of saline, 0.8 pmol x kg(-1) x min(-1) PYY(1-36) and PYY(3-36). Only four participants completed PYY(3-36) infusions because of nausea. Subsequently, six lean and eight obese participants completed 0.2 pmol x kg(-1) x min(-1) PYY(3-36) and 1.6 pmol x kg(-1) x min(-1) PYY(1-36) infusions. PYY(3-36) [corrected] produced [corrected] lower ratings of well-being and [corrected] increases in heart rate, [corrected] FFA, and [corrected] postprandial [corrected] insulin concentrations. Furthermore, high-dose [corrected] PYY(3-36) (0.8 [corrected] pmol x kg(-1) x min(-1)) produced decreased [corrected] EI and increased postprandial [corrected] glucose concentrations and tendency to reduced EE [corrected]
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Affiliation(s)
- Birgitte Sloth
- Department of Human Nutrition, Centre for Advanced Food Studies, Faculty of Life Sciences, University of Copenhagen, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark.
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Beck B. Neuropeptide Y in normal eating and in genetic and dietary-induced obesity. Philos Trans R Soc Lond B Biol Sci 2007; 361:1159-85. [PMID: 16874931 PMCID: PMC1642692 DOI: 10.1098/rstb.2006.1855] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neuropeptide Y (NPY) is one the most potent orexigenic peptides found in the brain. It stimulates food intake with a preferential effect on carbohydrate intake. It decreases latency to eat, increases motivation to eat and delays satiety by augmenting meal size. The effects on feeding are mediated through at least two receptors, the Y1 and Y5 receptors. The NPY system for feeding regulation is mostly located in the hypothalamus. It is formed of the arcuate nucleus (ARC), where the peptide is synthesized, and the paraventricular (PVN), dorsomedial (DMN) and ventromedial (VMN) nuclei and perifornical area where it is active. This activity is modulated by the hindbrain and limbic structures. It is dependent on energy availability, e.g. upregulation with food deprivation or restriction, and return to baseline with refeeding. It is also sensitive to diet composition with variable effects of carbohydrates and fats. Leptin signalling and glucose sensing which are directly linked to diet type are the most important factors involved in its regulation. Absence of leptin signalling in obesity models due to gene mutation either at the receptor level, as in the Zucker rat, the Koletsky rat or the db/db mouse, or at the peptide level, as in ob/ob mouse, is associated with increased mRNA abundance, peptide content and/or release in the ARC or PVN. Other genetic obesity models, such as the Otsuka-Long-Evans-Tokushima Fatty rat, the agouti mouse or the tubby mouse, are characterized by a diminution in NPY expression in the ARC nucleus and by a significant increase in the DMN. Further studies are necessary to determine the exact role of NPY in these latter models. Long-term exposure to high-fat or high-energy palatable diets leads to the development of adiposity and is associated with a decrease in hypothalamic NPY content or expression, consistent with the existence of a counter-regulatory mechanism to diminish energy intake and limit obesity development. On the other hand, an overactive NPY system (increased mRNA expression in the ARC associated with an upregulation of the receptors) is characteristic of rats or rodent strains sensitive to dietary-induced obesity. Finally, NPY appears to play an important role in body weight and feeding regulation, and while it does not constitute the only target for drug treatment of obesity, it may nevertheless provide a useful target in conjunction with others.
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Affiliation(s)
- B Beck
- Université Henri Poincaré, Neurocal, Nancy, France.
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48
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Simpson RC, Patti AL, Matuszewski BK. Determination of a Selective Neuropeptide Y5 Receptor Antagonist in Human Plasma and Urine by HPLC with Tandem Mass Spectrometric Detection. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070500416668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Richard C. Simpson
- a Department of Drug Metabolism , Merck Research Laboratories , West Point, Pennsylvania, USA
| | - Adrienne L. Patti
- a Department of Drug Metabolism , Merck Research Laboratories , West Point, Pennsylvania, USA
| | - Bogdan K. Matuszewski
- a Department of Drug Metabolism , Merck Research Laboratories , West Point, Pennsylvania, USA
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49
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Keen-Rhinehart E, Bartness TJ. NPY Y1 receptor is involved in ghrelin- and fasting-induced increases in foraging, food hoarding, and food intake. Am J Physiol Regul Integr Comp Physiol 2007; 292:R1728-37. [PMID: 17204592 PMCID: PMC3509278 DOI: 10.1152/ajpregu.00597.2006] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fasting triggers a constellation of physiological and behavioral changes, including increases in peripherally produced ghrelin and centrally produced hypothalamic neuropeptide Y (NPY). Refeeding stimulates food intake in most species; however, hamsters primarily increase foraging and food hoarding with smaller increases in food intake. Fasting-induced increases in foraging and food hoarding in Siberian hamsters are mimicked by peripheral ghrelin, central NPY, and NPY Y1 receptor agonist injections. Because fasting stimulates ghrelin and subsequently NPY synthesis/release, it may be that fasting-induced increased hoarding is mediated by NPY Y1 receptor activation. Therefore, we asked: Can an Y1 receptor antagonist block fasting- or ghrelin-induced increases in foraging, food hoarding, and food intake? This was accomplished by injecting the NPY Y1 receptor antagonist 1229U91 intracerebroventricularly in hamsters fasted, fed, or given peripheral ghrelin injections and housed in a running wheel-based food delivery foraging system coupled with simulated-burrow housing. Three foraging conditions were used: 1) no running wheel access, free food, 2) running wheel access, free food, or 3) foraging requirement (10 revolutions/pellet) for food. Fasting was a more potent stimulator of foraging and food hoarding than ghrelin. Concurrent injections of 1229U91 completely blocked fasting- and ghrelin-induced increased foraging and food intake and attenuated, but did not always completely block, fasting- and ghrelin-induced increases in food hoarding. Collectively, these data suggest that the NPY Y1 receptor is important for the effects of ghrelin- and fasting-induced increases in foraging and food intake, but other NPY receptors and/or other neurochemical systems are involved in increases in food hoarding.
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Affiliation(s)
- Erin Keen-Rhinehart
- Department of Biology, 24 Peachtree Center Ave. NE, Georgia State University, Atlanta, GA 30302-4010, USA
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Takahashi T, Sakuraba A, Hirohashi T, Shibata T, Hirose M, Haga Y, Nonoshita K, Kanno T, Ito J, Iwaasa H, Kanatani A, Fukami T, Sato N. Novel potent neuropeptide Y Y5 receptor antagonists: Synthesis and structure–activity relationships of phenylpiperazine derivatives. Bioorg Med Chem 2006; 14:7501-11. [PMID: 16919461 DOI: 10.1016/j.bmc.2006.07.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Accepted: 07/07/2006] [Indexed: 11/20/2022]
Abstract
A series of phenylpiperazine derivatives were synthesized and evaluated for their neuropeptide Y (NPY) Y5 receptor antagonistic activities. The benzindane portion of 2 was replaced by 1-phenylpiperazine, resulting in novel urea derivative 3f. Subsequent optimization of the phenylpiperazine template by substitution of the phenyl moiety resulted in a series of (2-methanesulfonamidephenyl)piperazine derivatives that showed potent binding affinity and antagonistic activity for the Y5 receptor.
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Affiliation(s)
- Toshiyuki Takahashi
- Tsukuba Research Institute, Banyu Pharmaceutical Co., Ltd, Okubo 3, Tsukuba 300-2611, Japan
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