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Shin H, Sharma R, Neupane C, Pham TL, Park SE, Lee SY, Kim HW, Bae YM, Stern JE, Park JB. Tonic NMDAR Currents of NR2A-Containing NMDARs Represent Altered Ambient Glutamate Concentration in the Supraoptic Nucleus. eNeuro 2024; 11:ENEURO.0279-23.2023. [PMID: 38176904 PMCID: PMC10863629 DOI: 10.1523/eneuro.0279-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/03/2023] [Accepted: 12/21/2023] [Indexed: 01/06/2024] Open
Abstract
NMDA receptors (NMDARs) modulate glutamatergic excitatory tone in the brain via two complementary modalities: a phasic excitatory postsynaptic current and a tonic extrasynaptic modality. Here, we demonstrated that the tonic NMDAR-current (I NMDA) mediated by NR2A-containing NMDARs is an efficient biosensor detecting the altered ambient glutamate level in the supraoptic nucleus (SON). I NMDA of magnocellular neurosecretory cells (MNCs) measured by nonselective NMDARs antagonist, AP5, at holding potential (V holding) -70 mV in low concentration of ECF Mg2+ ([Mg2+]o) was transiently but significantly increased 1-week post induction of a DOCA salt hypertensive model rat which was compatible with that induced by a NR2A-selective antagonist, PEAQX (I PEAQX) in both DOCA-H2O and DOCA-salt groups. In agreement, NR2B antagonist, ifenprodil, or NR2C/D antagonist, PPDA, did not affect the holding current (I holding) at V holding -70 mV. Increased ambient glutamate by exogenous glutamate (10 mM) or excitatory amino acid transporters (EAATs) antagonist (TBOA, 50 mM) abolished the I PEAQX difference between two groups, suggesting that attenuated EAATs activity increased ambient glutamate concentration, leading to the larger I PEAQX in DOCA-salt rats. In contrast, only ifenprodil but not PEAQX and PPDA uncovered I NMDA at V holding +40 mV under 1.2 mM [Mg2+]o condition. I ifenprodil was not different in DOCA-H2O and DOCA-salt groups. Finally, NR2A, NR2B, and NR2D protein expression were not different in the SON of the two groups. Taken together, NR2A-containing NMDARs efficiently detected the increased ambient glutamate concentration in the SON of DOCA-salt hypertensive rats due to attenuated EAATs activity.
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Affiliation(s)
- Hyunjin Shin
- Department of Physiology & Medical Science, College of Medicine & Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea
| | - Ramesh Sharma
- Department of Physiology & Medical Science, College of Medicine & Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Chiranjivi Neupane
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Thuy Linh Pham
- Department of Physiology & Medical Science, College of Medicine & Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea
| | - Su Eun Park
- Department of Physiology & Medical Science, College of Medicine & Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea
| | - So Yeong Lee
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyun-Woo Kim
- Department of Physiology & Medical Science, College of Medicine & Brain Research Institute, Chungnam National University, Daejeon 35015, South Korea
| | - Young Min Bae
- Department of Physiology, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Javier E Stern
- Neuroscience Institute and Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, Georgia 30302
| | - Jin Bong Park
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
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Wang W, Wang Y, Liu Y, Cao G, Di R, Wang J, Chu M. Polymorphism and expression of GLUD1 in relation to reproductive performance in Jining Grey goats. Arch Anim Breed 2023; 66:411-419. [PMID: 38205377 PMCID: PMC10776882 DOI: 10.5194/aab-66-411-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 10/06/2023] [Indexed: 01/12/2024] Open
Abstract
Understanding the molecular mechanism of mammalian reproduction (puberty and prolificacy) will play a part in improving animal reproductive performance. GLUD1 (glutamate dehydrogenase 1) is important for mammalian reproduction, as shown in previous studies; however, its roles in puberty and prolificacy have rarely been reported. In this study, we designed seven pairs of primers (P1 to P7) for cloning and sequencing genomic DNA of Jining Grey goats and Liaoning Cashmere goats. Primer 8 (P8) was designed to detect single nucleotide polymorphism (SNP) of the GLUD1 in both sexually precocious and high-fecundity breeds (Jining Grey, Nanjiang Brown and Matou goats) and sexually late-maturing and low-fecundity breeds (Liaoning Cashmere, Inner Mongolia Cashmere and Taihang goats) by PCR-RFLP (restriction fragment length polymorphism). The real-time quantitative polymerase chain reaction (RT-qPCR) technique was used to detect the expression of GLUD1 in a variety of tissues. The results showed that the A197C mutation was only found in the amplification product of P6. For this SNP locus, only two genotypes (AA and AC) were detected in Nanjiang Brown goats, while three genotypes (AA, AC and CC) were detected in the other five breeds. In Jining Grey goats, the frequency of genotypes AA, AC and CC was 0.69, 0.26 and 0.05, respectively. In Jining Grey goats, AA genotype had 0.54 (P < 0.05 ) and 0.3 (P < 0.05 ) more kids than the CC and AC genotype, respectively, and no significant difference (P > 0.05 ) was found in kidding number between the AC and CC genotype. GLUD1 was expressed in five tissues of different developmental stages. The expression level of GLUD1 in the hypothalamus was higher than that in the other four tissues except during puberty of Liaoning Cashmere goats. In puberty in goats, GLUD1 expression was significantly higher in ovaries than that in the juvenile period (P < 0.01 ). RT-qPCR results showed that the expression of GLUD1 in ovaries may relate to the puberty of goats. The present study preliminarily indicated that there might be an association between the 197 locus of GLUD1 and sexual precocity in goats, and allele A of GLUD1 was a potential DNA marker for improving kidding number in Jining Grey goats.
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Affiliation(s)
- Wei Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yongjuan Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
| | - Yufang Liu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Guiling Cao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Ran Di
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jinyu Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
| | - Mingxing Chu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Finn DA. Stress and gonadal steroid influences on alcohol drinking and withdrawal, with focus on animal models in females. Front Neuroendocrinol 2023; 71:101094. [PMID: 37558184 PMCID: PMC10840953 DOI: 10.1016/j.yfrne.2023.101094] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 07/06/2023] [Accepted: 08/06/2023] [Indexed: 08/11/2023]
Abstract
Sexually dimorphic effects of alcohol, following binge drinking, chronic intoxication, and withdrawal, are documented at the level of the transcriptome and in behavioral and physiological responses. The purpose of the current review is to update and to expand upon contributions of the endocrine system to alcohol drinking and withdrawal in females, with a focus on animal models. Steroids important in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes, the reciprocal interactions between these axes, the effects of chronic alcohol use on steroid levels, and the genomic and rapid membrane-associated effects of steroids and neurosteroids in models of alcohol drinking and withdrawal are described. Importantly, comparison between males and females highlight some divergent effects of sex- and stress-steroids on alcohol drinking- and withdrawal-related behaviors, and the distinct differences in response emphasize the importance of considering sex in the development of novel pharmacotherapies for the treatment of alcohol use disorder.
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Affiliation(s)
- Deborah A Finn
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States; Department of Research, VA Portland Health Care System, Portland, OR, United States.
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Zhu Y, Wang Z, Yu S, Zhao C, Xu B, Liu R, Xu L, Guo Y. Neuroprotective Effect of Ginseng Fibrous Root Enzymatic Hydrolysate against Oxidative Stress. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27227824. [PMID: 36431931 PMCID: PMC9697448 DOI: 10.3390/molecules27227824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/06/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
Oxidative stress is one of the potential causes of nervous system disease. Ginseng extract possesses excellent antioxidant activity; however, little research on the function of the ginseng fibrous root. This study aimed to investigate the neuroprotective effects of ginseng fibrous root to alleviate the pathogenesis of Alzheimer's disease (AD) against oxidative stress. Ginseng fibrous root enzymatic hydrolysate (GFREH) was first prepared by digesting ginseng fibrous roots with alkaline protease. In vitro, the GFREH showed antioxidant activities in free radical scavenging mechanisms. With a cellular model of AD, GFREH inhibited the increase in Ca2+ levels and intracellular ROS content, maintained the balance of mitochondrial membrane potential, and relieved L-glutamic acid-induced neurotoxicity. In vivo, GFREH improved the survival rate of Caenorhabditis elegans (C. elegans) under oxidative stress, upregulated SOD-3 expression, and reduced reactive oxygen species (ROS) content. Therefore, our findings provide evidence for the alleviation effect of GFREH against oxidative stress in neuroprotection, which may accelerate the development of anti-Alzheimer's drugs and treatments in the future.
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Affiliation(s)
- Yuhua Zhu
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Ziyan Wang
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Shuxuan Yu
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Chong Zhao
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Baofeng Xu
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Rui Liu
- Department of VIP Unit, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Li Xu
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
- Correspondence: (L.X.); (Y.G.)
| | - Yi Guo
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
- Correspondence: (L.X.); (Y.G.)
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GABAergic and Glutamatergic Phenotypes of Neurons Expressing Calcium-Binding Proteins in the Preoptic Area of the Guinea Pig. Int J Mol Sci 2022; 23:ijms23147963. [PMID: 35887305 PMCID: PMC9320123 DOI: 10.3390/ijms23147963] [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: 06/27/2022] [Revised: 07/18/2022] [Accepted: 07/18/2022] [Indexed: 11/17/2022] Open
Abstract
The mammalian preoptic area (POA) has large populations of calbindin (CB), calretinin (CR) and parvalbumin (PV) neurons, but phenotypes of these cells are unknown. Therefore, the question is whether neurons expressing CB, CR, and/or PV are GABAergic or glutamatergic. Double-immunofluorescence staining followed by epifluorescence and confocal microscopy was used to determine the coexpression patterns of CB, CR and PV expressing neurons with vesicular GABA transporters (VGAT) as specific markers of GABAergic neurons and vesicular glutamate transporters (VGLUT 2) as specific markers of glutamatergic neurons. The guinea pig was adopted as, like humans, it has a reproductive cycle with a true luteal phase and a long gestation period. The results demonstrated that in the guinea pig POA of both sexes, ~80% of CB+ and ~90% of CR+ neurons coexpress VGAT; however, one-fifth of CB+ neurons and one-third of CR+ cells coexpress VGLUT. About two-thirds of PV+ neurons express VGAT, and similar proportion of them coexpress VGLUT. Thus, many CB+, CR+ and PV+ neurons may be exclusively GABAergic (VGAT-expressing cells) or glutamatergic (VGLUT-expressing cells); however, at least a small fraction of CR+ cells and at least one-third of PV+ cells are likely neurons with a dual GABA/glutamate phenotype that may coexpress both transporters.
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Royo M, Escolano BA, Madrigal MP, Jurado S. AMPA Receptor Function in Hypothalamic Synapses. Front Synaptic Neurosci 2022; 14:833449. [PMID: 35173598 PMCID: PMC8842481 DOI: 10.3389/fnsyn.2022.833449] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 01/03/2022] [Indexed: 12/15/2022] Open
Abstract
AMPA receptors (AMPARs) are critical for mediating glutamatergic synaptic transmission and plasticity, thus playing a major role in the molecular machinery underlying cellular substrates of memory and learning. Their expression pattern, transport and regulatory mechanisms have been extensively studied in the hippocampus, but their functional properties in other brain regions remain poorly understood. Interestingly, electrophysiological and molecular evidence has confirmed a prominent role of AMPARs in the regulation of hypothalamic function. This review summarizes the existing evidence on AMPAR-mediated transmission in the hypothalamus, where they are believed to orchestrate the role of glutamatergic transmission in autonomous, neuroendocrine function, body homeostasis, and social behavior.
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7
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Leithead AB, Tasker JG, Harony‐Nicolas H. The interplay between glutamatergic circuits and oxytocin neurons in the hypothalamus and its relevance to neurodevelopmental disorders. J Neuroendocrinol 2021; 33:e13061. [PMID: 34786775 PMCID: PMC8951898 DOI: 10.1111/jne.13061] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/14/2021] [Accepted: 10/30/2021] [Indexed: 11/27/2022]
Abstract
Oxytocin (OXT) neurons of the hypothalamus are at the center of several physiological functions, including milk ejection, uterus contraction, and maternal and social behavior. In lactating females, OXT neurons show a pattern of burst firing and inter-neuron synchronization during suckling that leads to pulsatile release of surges of OXT into the bloodstream to stimulate milk ejection. This pattern of firing and population synchronization may be facilitated in part by hypothalamic glutamatergic circuits, as has been observed in vitro using brain slices obtained from male rats and neonates. However, it remains unknown how hypothalamic glutamatergic circuits influence OXT cell activity outside the context of lactation. In this review, we summarize the in vivo and in vitro studies that describe the synchronized burst firing pattern of OXT neurons and the implication of hypothalamic glutamate in this pattern of firing. We also make note of the few studies that have traced glutamatergic afferents to the hypothalamic paraventricular and supraoptic nuclei. Finally, we discuss the genetic findings implicating several glutamatergic genes in neurodevelopmental disorders, including autism spectrum disorder, thus underscoring the need for future studies to investigate the impact of these mutations on hypothalamic glutamatergic circuits and the OXT system.
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Affiliation(s)
- Amanda B. Leithead
- Department of PsychiatryIcahn School of Medicine at Mount SinaiNew YorkNYUSA
- Seaver Autism Center for Research and TreatmentNew YorkNYUSA
- Department of NeuroscienceIcahn School of Medicine at Mount SinaiNew YorkNYUSA
- Friedman Brain Institute at the Icahn School of Medicine at Mount SinaiNew YorkNYUSA
| | - Jeffrey G. Tasker
- Neurobiology DivisionDepartment of Cell and Molecular BiologyTulane UniversityNew OrleansLAUSA
| | - Hala Harony‐Nicolas
- Department of PsychiatryIcahn School of Medicine at Mount SinaiNew YorkNYUSA
- Seaver Autism Center for Research and TreatmentNew YorkNYUSA
- Department of NeuroscienceIcahn School of Medicine at Mount SinaiNew YorkNYUSA
- Friedman Brain Institute at the Icahn School of Medicine at Mount SinaiNew YorkNYUSA
- Mindich Child Health and Development Institute at the Icahn School of Medicine at Mount SinaiNew YorkNYUSA
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8
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Bi N, Ding J, Zou R, Gu X, Liu ZH, Wang HL. Developmental exposure of bisphenol A induces spatial memory deficits by weakening the excitatory neural circuits of CA3-CA1 and EC-CA1 in mice. Toxicol Appl Pharmacol 2021; 426:115641. [PMID: 34242568 DOI: 10.1016/j.taap.2021.115641] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/08/2021] [Accepted: 07/04/2021] [Indexed: 10/20/2022]
Abstract
Bisphenol-A (BPA) is an environmental endocrine disruptor and impairs learning and memory. However, the direct evidence for BPA exposure affecting neural circuits has been limited. In this study, a virus tracing assay has been established to explore the brain's neural circuits. Thy1-Cre mice were used to investigate the effects of BPA on the neural projection of glutamatergic pyramidal neurons in hippocampal CA1 based on Thy1 promoter. These transgenic mice were orally exposed to BPA (0, 0.5 mg/kg/day) from postnatal day (PND) 0 to PND60 and then subjected to behavioral tests. Morris water maze(MWM)and Barnes maze's showed that the spatial memory was seriously impaired in BPA exposed Thy1-Cre mice. Virus tracing assay indicated that CA1 pyramidal neurons mainly received neural inputs from hippocampal CA3, entorhinal cortex (EC), and medial septum (MS). The analysis showed that BPA reduced the number of RV+ neurons in CA3 and EC but not MS. The immunohistochemistry experiment displayed that BPA decreased the percentage of CaMKIIRV+ cells in CA3 and EC. The results demonstrated that the synaptic connection of upstream glutamatergic neurons and CA1 pyramidal cells was weakened by BPA exposure. These point to potentially detrimental effects of BPA exposure on the excitatory neural circuit of CA3-CA1 and EC-CA1 in memory formation. Thus, our findings revealed that the decrease in excitatory neural circuits of CA3-CA1 and EC-CA1 contribute to the BPA-induced spatial memory deficits in Thy1-Cre mice.
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Affiliation(s)
- Nanxi Bi
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Jinjun Ding
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Rongxin Zou
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xiaozhen Gu
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Zhi-Hua Liu
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Hui-Li Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
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Zhang J, Liu R, Zhang D, Zhang Z, Zhu J, Xu L, Guo Y. Neuroprotective effects of maize tetrapeptide-anchored gold nanoparticles in Alzheimer's disease. Colloids Surf B Biointerfaces 2021; 200:111584. [PMID: 33508658 DOI: 10.1016/j.colsurfb.2021.111584] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 12/18/2022]
Abstract
Nanopeptide assembled from peptide-anchored nanoparticles possess an enormous research potential in the field of cellular medicine and disease treatment. The aim of this study was to explore the neuroprotective effects of maize tetrapeptide anchored gold nanoparticles against l-glutamic acid-induced PC12 cell apoptosis and a murine Alzheimer's disease model induced by aluminum chloride and d-galactose. The results revealed that the nanopeptide antioxidant inhibited intracellular ROS accumulation and promoted cell differentiation than that of maize bioactive tetrapeptide. Compared with untreated Alzheimer's disease model mice, nanopeptide administration shortened the escape latency time in a water maze test and improved the movements in the autonomic activity test. After 16 days of nanopeptide administration, the central cholinergic system function of acetylcholine and cholineacetyltransferase were enhanced, and the level of acetylcholinesterase was reduced. It also increased superoxide dismutase and glutathione peroxidase activity in sera and hypothalami. Moreover, nanopeptide treatment upregulated cerebral nuclear factor erythroid 2-related factor 2 and heme-oxygenase-1 and downregulated kelch-like ECH-associated protein 1 relative to untreated Alzheimer's disease model mice. Thus, the novel nanopeptide is expected to be used as the neuroprotective agent to prevent Alzheimer's disease.
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Affiliation(s)
- Junrong Zhang
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, 130012, PR China
| | - Rui Liu
- China-Japan Union Hospital of Jilin University, Changchun, 130033, PR China
| | - Dechen Zhang
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, 130012, PR China
| | - Zhixian Zhang
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, 130012, PR China
| | - Jinming Zhu
- China-Japan Union Hospital of Jilin University, Changchun, 130033, PR China
| | - Li Xu
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, 130012, PR China
| | - Yi Guo
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, 130012, PR China.
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Liu J, Dimitrov S, Sawangjit A, Born J, Ehrlich I, Hallschmid M. Short-term high-fat feeding induces a reversible net decrease in synaptic AMPA receptors in the hypothalamus. J Nutr Biochem 2021; 87:108516. [PMID: 33022406 DOI: 10.1016/j.jnutbio.2020.108516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 07/09/2020] [Accepted: 09/11/2020] [Indexed: 01/05/2023]
Abstract
Dietary obesity compromises brain function, but the effects of high-fat food on synaptic transmission in hypothalamic networks, as well as their potential reversibility, are yet to be fully characterized. We investigated the impact of high-fat feeding on a hallmark of synaptic plasticity, i.e., the expression of glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) that contain the subunits GluA1 and GluA2, in hypothalamic and cortical synaptoneurosomes of male rats. In the main experiment (experiment 1), three days, but not one day of high-fat diet (HFD) decreased the levels of AMPAR GluA1 and GluA2 subunits, as well as GluA1 phosphorylation at Ser845, in hypothalamus but not cortex. In experiment 2, we compared the effects of the three-day HFD with those a three-day HFD followed by four recovery days of normal chow. This experiment corroborated the suppressive effect of high-fat feeding on hypothalamic but not cortical AMPAR GluA1, GluA2, and GluA1 phosphorylation at Ser845, and indicated that the effects are reversed by normal-chow feeding. High-fat feeding generally increased energy intake, body weight, and serum concentrations of insulin, leptin, free fatty acids, and corticosterone; only the three-day HFD increased wakefulness assessed via video analysis. Results indicate a reversible down-regulation of hypothalamic glutamatergic synaptic strength in response to short-term high-fat feeding. Preceding the manifestation of obesity, this rapid change in glutamatergic neurotransmission may underlie counter-regulatory efforts to prevent excess body weight gain, and therefore, represent a new target of interventions to improve metabolic control.
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Affiliation(s)
- Jianfeng Liu
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Stoyan Dimitrov
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University Tübingen (IDM), Tübingen, Germany
| | - Anuck Sawangjit
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Jan Born
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University Tübingen (IDM), Tübingen, Germany
| | - Ingrid Ehrlich
- Hertie Institute for Clinical Brain Research and Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany; Department of Neurobiology, Institute for Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart, Germany
| | - Manfred Hallschmid
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University Tübingen (IDM), Tübingen, Germany.
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11
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Ammari R, Broberger C. Pre- and post-synaptic modulation by GABA B receptors of rat neuroendocrine dopamine neurones. J Neuroendocrinol 2020; 32:e12881. [PMID: 32803906 DOI: 10.1111/jne.12881] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 05/22/2020] [Accepted: 06/05/2020] [Indexed: 12/17/2022]
Abstract
The secretion of prolactin from the pituitary is negatively controlled by tuberoinfundibular dopamine (TIDA) neurones. The electrical properties of TIDA cells have recently been identified as a modulatory target of neurotransmitters and hormones in the lactotrophic axis. The role of the GABAB receptor in this control has received little attention, yet is of particular interest because it may act as a TIDA neurone autoreceptor. Here, this issue was explored in a spontaneously active rat TIDA in vitro slice preparation using whole-cell recordings. Application of the GABAB receptor agonist, baclofen, dose-dependently slowed down or abolished the network oscillations typical of this preparation. Pharmacological manipulations identify the underlying mechanism as an outward current mediated by G-protein-coupled inwardly rectifying K+ -like channels. In addition to this postsynaptic modulation, we describe a presynaptic modulation where GABAB receptors restrain the release of glutamate and GABA onto TIDA neurones. Our data identify both pre- and postsynaptic modulation of TIDA neurones by GABAB receptors that may play a role in the neuronal network control of pituitary prolactin secretion and lactation.
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Affiliation(s)
- Rachida Ammari
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Christian Broberger
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
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12
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Abstract
Sexually dimorphic effects of alcohol exposure throughout life have been documented in clinical and preclinical studies. In the past, rates of alcohol use disorder (AUD) were higher in men than in women, but over the past 10 years, the difference between sexes in prevalence of AUD and binge drinking has narrowed. Recent evidence adds to historical data regarding the influence of sex steroids on alcohol drinking and the interaction with stress-related steroids. This review considers the contribution of the endocrine system to alcohol drinking in females, with a focus on the hypothalamic pituitary gonadal axis and the hypothalamic pituitary adrenal axis and their reciprocal interactions. Emphasis is given to preclinical studies that examined genomic and rapid membrane effects of estrogen, progesterone, glucocorticoids, and GABAergic neurosteroids for their effects on alcohol drinking and models of relapse. Pertinent comparisons to data in males highlight divergent effects of sex and stress steroids on alcohol drinking and emphasize the importance of considering sex in the development of novel pharmacotherapeutic targets for the treatment of AUD. For instance, pharmacological strategies targeting the corticotropin releasing factor and glucocorticoid receptor systems may be differentially effective in males and females, whereas strategies to enhance GABAergic neurosteroids may represent a biomarker of treatment efficacy in both sexes.
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Affiliation(s)
- Deborah A Finn
- Oregon Health & Science University, Portland, Oregon.,Veterans Affairs Portland Health Care System, Portland, Oregon
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13
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Gosztonyi G, Ludwig H, Bode L, Kao M, Sell M, Petrusz P, Halász B. Obesity induced by Borna disease virus in rats: key roles of hypothalamic fast-acting neurotransmitters and inflammatory infiltrates. Brain Struct Funct 2020; 225:1459-1482. [PMID: 32394093 DOI: 10.1007/s00429-020-02063-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 03/21/2020] [Indexed: 12/30/2022]
Abstract
Human obesity epidemic is increasing worldwide with major adverse consequences on health. Among other possible causes, the hypothesis of an infectious contribution is worth it to be considered. Here, we report on an animal model of virus-induced obesity which might help to better understand underlying processes in human obesity. Eighty Wistar rats, between 30 and 60 days of age, were intracerebrally inoculated with Borna disease virus (BDV-1), a neurotropic negative-strand RNA virus infecting an unusually broad host spectrum including humans. Half of the rats developed fatal encephalitis, while the other half, after 3-4 months, continuously gained weight. At tripled weights, rats were sacrificed by trans-cardial fixative perfusion. Neuropathology revealed prevailing inflammatory infiltrates in the median eminence (ME), progressive degeneration of neurons of the paraventricular nucleus, the entorhinal cortex and the amygdala, and a strikingly high-grade involution of the hippocampus with hydrocephalus. Immune histology revealed that major BDV-1 antigens were preferentially present at glutamatergic receptor sites, while GABAergic areas remained free from BDV-1. Virus-induced suppression of the glutamatergic system caused GABAergic predominance. In the hypothalamus, this shifted the energy balance to the anabolic appetite-stimulating side governed by GABA, allowing for excessive fat accumulation in obese rats. Furthermore, inflammatory infiltrates in the ME and ventro-medial arcuate nucleus hindered free access of appetite-suppressing hormones leptin and insulin. The hormone transport system in hypothalamic areas outside the ME became blocked by excessively produced leptin, leading to leptin resistance. The resulting hyperleptinemic milieu combined with suppressed glutamatergic mechanisms was a characteristic feature of the found metabolic pathology. In conclusion, the study provided clear evidence that BDV-1 induced obesity in the rat model is the result of interdependent structural and functional metabolic changes. They can be explained by an immunologically induced hypothalamic microcirculation-defect, combined with a disturbance of neurotransmitter regulatory systems. The proposed mechanism may also have implications for human health. BDV-1 infection has been frequently found in depressive patients. Independently, comorbidity between depression and obesity has been reported, either. Future studies should address the exciting question of whether BDV-1 infection could be a link, whatsoever, between these two conditions.
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Affiliation(s)
- Georg Gosztonyi
- Institute of Neuropathology, Charité, University Medicine Berlin, 10117, Berlin, Germany.
| | - Hanns Ludwig
- Freelance Bornavirus Workgroup, 14163, Berlin, Germany
| | - Liv Bode
- Freelance Bornavirus Workgroup, 14163, Berlin, Germany
| | - Moujahed Kao
- Landesbetrieb Hessisches Landeslabor, 35392, Giessen, Germany
| | - Manfred Sell
- Division of Pathology, Martin Luther Hospital, 12351, Berlin, Germany
| | - Peter Petrusz
- Department of Cell and Developmental Biology, University of North Carolina At Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Béla Halász
- Neuromorphological and Neuroendocrine Research Laboratory, Semmelweis University, 1094, Budapest, Hungary
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14
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Liu ZQ, Liu N, Huang SS, Lin MM, Qin S, Wu JC, Liang ZQ, Qin ZH, Wang Y. NADPH protects against kainic acid-induced excitotoxicity via autophagy-lysosome pathway in rat striatum and primary cortical neurons. Toxicology 2020; 435:152408. [PMID: 32057834 DOI: 10.1016/j.tox.2020.152408] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/24/2020] [Accepted: 02/10/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE To investigate the effects and mechanisms of NADPH on Kainic acid (KA)-induced excitotoxicity. METHODS KA, a non-N-methyl-d-aspartate glutamate receptor agonist, was exposed to adult SD rats via intrastriatal injection and rat primary cortical neurons to establish excitotoxic models in vivo and in vitro, respectively. To determine the effects of NADPH on KA-induced excitotoxicity, neuronal survival, neurologically behavioral score and oxidative stress were evaluated. To explore the mechanisms of neuroprotective effects of NADPH, the autophagy-lysosome pathway related proteins were detected. RESULTS In vivo, NADPH (1 mg/kg or 2 mg/kg) diminished KA (2.5 nmol)-induced enlargement of lesion size in striatum, improved KA-induced dyskinesia and reversed KA-induced activation of glial cells. Nevertheless, the neuroprotective effect of NADPH was not significant under the condition of autophagy activation. NADPH (2 mg/kg) inhibited KA (2.5 nmol)-induced down-regulation of TP-53 induced glycolysis and apoptosis regulator (TIGAR) and p62, and up-regulation of the protein levels of LC3-II/LC3-I, Beclin-1 and Atg5. In vitro, the excitotoxic neuronal injury was induced after KA (50 μM, 100 μM or 200 μM) treatment as demonstrated by decreased cell viability. Moreover, KA (100 μM) increased the intracellular levels of calcium and reactive oxygen species (ROS) and declined the levels of the reduced form of glutathione (GSH). Pretreatment of NADPH (10 μM) effectively reversed these changes. Meanwhile NADPH (10 μM) inhibited KA (100 μM)-induced down-regulation of TIGAR and p62, and up-regulation of the ratio of LC3-II/LC3-I, Beclin-1, Atg5, active-cathepsin B and active-cathepsin D. CONCLUSIONS Our data provide a possible mechanism that NADPH ameliorates KA-induced excitotoxicity by blocking the autophagy-lysosome pathway and up-regulating TIGAR along with its antioxidant properties.
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Affiliation(s)
- Zi-Qi Liu
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Na Liu
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Si-Si Huang
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Miao-Miao Lin
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Shu Qin
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Jun-Chao Wu
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Zhong-Qin Liang
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Zheng-Hong Qin
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Yan Wang
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases and Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, China.
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15
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Glutamate Supply Reactivates Ovarian Function while Increases Serum Insulin and Triiodothyronine Concentrations in Criollo x Saanen-Alpine Yearlings' Goats during the Anestrous Season. Animals (Basel) 2020; 10:ani10020234. [PMID: 32024282 PMCID: PMC7070922 DOI: 10.3390/ani10020234] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/30/2020] [Accepted: 01/30/2020] [Indexed: 12/21/2022] Open
Abstract
The possible effect of glutamate supplementation upon ovarian reactivation and serum concentrations of insulin (INS) and triiodothyronine (T3) in anestrous yearling goats was evaluated. Goats (n = 32, 12 mo., 26° North, 1117 m) with a similar live weight (LW) and body condition score (BCS) were blood sampled twice per week for two weeks (2 × 1 week × 2 weeks) to confirm the anestrus status (<1 ng P4/mL; RIA). Thereafter, goats were randomly assigned to either 1) Glutamate (GLUT; n = 16, LW = 27.1 ± 1.09 kg, 3.5 ± 0.18 units, IV-supplemented with 7 mg of glutamate kg-1 LW), or 2) Control (CONT; n = 16; LW = 29.2 ± 1.09 kg; BCS = 3.5 ± 0.18, IV saline). During the treatment period, 16 goats (eight/group) were blood sampled twice per week for six weeks. Such serum samples (2 × 1 week × 6 weeks) were quantified by their P4 content to evaluate the ovarian-luteal activity, whereas a sample subset (1 × 1 week × 6 weeks) was used to quantify their INS & T3 content to evaluate their metabolic status. Neither LW (28.19 kg; p > 0.05) nor BCS (3.51 units; p > 0.05) differed between treatments. Goats depicting ovarian reactivation favored the GLUT group (50 vs. 12.5%; p < 0.05). Neither INS (1.72 ± 0.15 ng mL-1) nor T3 (2.32 ± 0.11 ng mL-1) differed between treatments, yet a treatment x time interaction regarding INS & T3 concentration across time favored (p < 0.05) the GLUT group. The results unveil exogenous glutamate as an interesting modulator not only of ovarian reactivation, but of metabolic hormone synthesis.
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16
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Melnick I, Krishtal OA, Colmers WF. Integration of energy homeostasis and stress by parvocellular neurons in rat hypothalamic paraventricular nucleus. J Physiol 2020; 598:1073-1092. [PMID: 31952096 DOI: 10.1113/jp279387] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/16/2020] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Central regulation of energy homeostasis and stress are believed to be reciprocally regulated, i.e. excessive food intake suppresses, while prolonged hunger exacerbates, stress responses in vivo. This relationship may be mediated by neuroendocrine parvocellular corticotropin-releasing hormone (CRH) neurons in the hypothalamic paraventricular nucleus that receive both stress- and feeding-related input. We find that hunger strongly and selectively potentiates, while re-feeding suppresses, a cellular analogue of a stress response induced by acute glucopenia in CRH neurons in rat hypothalamic slices. Neuronal activation in response to glucopenia was mediated synaptically, via the relative enhancement of glutamate over GABA input. These results illustrate how acute stress responses may be initiated in vivo and show that it is reciprocally integrated with energy balance via local hypothalamic mechanisms acting at the level of CRH neurons and their afferent terminals. ABSTRACT Increased food intake is a common response to help cope with stress, implying the existence of a previously postulated but imperfectly understood, inverse relationship between the regulation of feeding and stress. We have identified components of the neural circuitry that can integrate these homeostatic responses. Prior fasting (∼24 h) potentiates, and re-feeding suppresses, excitatory responses to acute glucopenia in about half of the corticotropin releasing hormone (CRH)-expressing, putatively neurosecretory, stress-related neurons in the paraventricular nucleus of the hypothalamus studied. Glucoprivation stress ex vivo resulted from a preferential relative increase in excitatory (glutamatergic) over inhibitory (GABAergic) inputs. Putative preautonomic cells were less sensitive to fasting, and showed a predominant inhibition to acute glucopenia. We conclude that hunger may sensitize hypothalamic stress responses by acting via local mechanisms, at the level of CRH neurons and their presynaptic inputs. Those mechanisms involve neither presynaptic ATP-sensitive potassium channels nor postsynaptic ATP levels.
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Affiliation(s)
- Igor Melnick
- Bogomoletz Institute of Physiology, Bogomoletz str 4, Kiev, 01024, Ukraine
| | - Oleg A Krishtal
- Bogomoletz Institute of Physiology, Bogomoletz str 4, Kiev, 01024, Ukraine
| | - William F Colmers
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada, T6G 2H7
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17
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Di S, Jiang Z, Wang S, Harrison LM, Castro-Echeverry E, Stuart TC, Wolf ME, Tasker JG. Labile Calcium-Permeable AMPA Receptors Constitute New Glutamate Synapses Formed in Hypothalamic Neuroendocrine Cells during Salt Loading. eNeuro 2019; 6:ENEURO.0112-19.2019. [PMID: 31300543 PMCID: PMC6675872 DOI: 10.1523/eneuro.0112-19.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 06/13/2019] [Accepted: 06/21/2019] [Indexed: 11/21/2022] Open
Abstract
Magnocellular neuroendocrine cells (MNCs) of the hypothalamus play a critical role in the regulation of fluid and electrolyte homeostasis. They undergo a dramatic structural and functional plasticity under sustained hyperosmotic conditions, including an increase in afferent glutamatergic synaptic innervation. We tested for a postulated increase in glutamate AMPA receptor expression and signaling in magnocellular neurons of the male rat hypothalamic supraoptic nucleus (SON) induced by chronic salt loading. While without effect on GluA1-4 subunit mRNA, salt loading with 2% saline for 5-7 d resulted in a selective increase in AMPA receptor GluA1 protein expression in the SON, with no change in GluA2-4 protein expression, suggesting an increase in the ratio of GluA1 to GluA2 subunits. Salt loading induced a corresponding increase in EPSCs in both oxytocin (OT) and vasopressin (VP) neurons, with properties characteristic of calcium-permeable AMPA receptor-mediated currents. Unexpectedly, the emergent AMPA synaptic currents were silenced by blocking protein synthesis and mammalian target of rapamycin (mTOR) activity in the slices, suggesting that the new glutamate synapses induced by salt loading require continuous dendritic protein synthesis for maintenance. These findings indicate that chronic salt loading leads to the induction of highly labile glutamate synapses in OT and VP neurons that are comprised of calcium-permeable homomeric GluA1 AMPA receptors. The glutamate-induced calcium influx via calcium-permeable AMPA receptors would be expected to play a key role in the induction and/or maintenance of activity-dependent synaptic plasticity that occurs in the magnocellular neurons during chronic osmotic stimulation.
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Affiliation(s)
- Shi Di
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
| | - ZhiYing Jiang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
| | - Sen Wang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
| | - Laura M Harrison
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
| | | | - Thomas C Stuart
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
| | - Marina E Wolf
- Department of Neuroscience, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
| | - Jeffrey G Tasker
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118
- Tulane Brain Institute, Tulane University, New Orleans, LA 70118
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18
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Zhang BB, Jin H, Bing YH, Zhang XY, Chu CP, Li YZ, Qiu DL. A Nitric Oxide-Dependent Presynaptic LTP at Glutamatergic Synapses of the PVN Magnocellular Neurosecretory Cells in vitro in Rats. Front Cell Neurosci 2019; 13:283. [PMID: 31316353 PMCID: PMC6610542 DOI: 10.3389/fncel.2019.00283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 06/11/2019] [Indexed: 11/13/2022] Open
Abstract
The magnocellular neurosecretory cells (MNCs) of the hypothalamic paraventricular nucleus (PVN) integrate incoming signals to secrete oxytocin (OT), and vasopressin (VP) from their nerve terminals in the posterior pituitary gland. In the absence of gamma-aminobutyric acid A (GABAA) and cannabinoids 1 (CB1) receptor activity, we used whole-cell patch-clamp recording, single-cell reverse transcription-multiplex polymerase chain reaction (SC-RT-mPCR), biocytin histochemistry and pharmacological methods to examine the mechanism of high frequency stimulus (HFS, 100 Hz)-induced long-term potentiation (LTP) at glutamatergic synapses in the PVN MNCs of juvenile male rats. Our results showed that HFS-induced LTP at glutamatergic synapses was accompanied by a decrease in the paired-pulse ratio (PPR) of the PVN MNCs. In these MNCs, HFS-induced LTP persisted in the presence of a group 1 metabotropic glutamate receptor (mGluR1) antagonist; however, it was abolished by an N-methyl-D-aspartic acid (NMDA) receptor blocker. Notably, HFS-induced LTP in the PVN MNCs was completely prevented by a nitric oxide synthase (NOS) inhibitor. The application of an NO donor not only induced the LTP of excitatory glutamatergic inputs in the PVN MNCs, but also occluded the HFS-induced LTP in these MNCs. Moreover, HFS-induced LTP in the PVN MNCs was also abolished by a specific protein kinase A (PKA) inhibitor, KT5720. SC-RT-mPCR analysis revealed that 64.5% (62/96) of MNCs expressed OT mRNA. Our results indicate that a HFS can induce an NMDA receptor and NO cascades dependent on presynaptic glutamatergic LTP in the PVN MNCs via a PKA signaling pathway.
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Affiliation(s)
- Bin-Bin Zhang
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China.,Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji, China
| | - Hua Jin
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China.,Department of Nephrology, Affiliated Hospital of Yanbian University, Yanji, China
| | - Yan-Hua Bing
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China.,Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji, China
| | - Xin-Yuan Zhang
- Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji, China
| | - Chun-Ping Chu
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China
| | - Yu-Zi Li
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China.,Department of Cardiology, Affiliated Hospital of Yanbian University, Yanji, China
| | - De-Lai Qiu
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji, China.,Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji, China
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19
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Abstract
The term neurosteroid refers to rapid membrane actions of steroid hormones and their derivatives that can modulate physiological functions and behavior via their interactions with ligand-gated ion channels. This chapter will highlight recent advances pertaining to the modulatory effects of a select group of neurosteroids that are primarily potent positive allosteric modulators of γ-aminobutyric acidA receptors (GABAARs). Nanomolar concentrations of neurosteroids, which occur in vivo, potentiate phasic and tonic forms of GABAAR-mediated inhibition, indicating that both synaptic and extrasynaptic GABAARs possess sensitivity to neurosteroids and contribute to the overall ability of neurosteroids to modulate central nervous system excitability. Common effects of alcohol and neurosteroids at GABAARs have stimulated research on the ability of neurosteroids to modulate alcohol's acute and chronic effects. Background on neurosteroid pharmacology and biosynthetic enzymes will be provided as it relates to experimental findings. Data will be summarized on alcohol and neurosteroid interactions across neuroanatomical regions and models of intoxication, consumption, dependence, and withdrawal. Evidence supports independent regulation of neurosteroid synthesis between periphery and brain as well as across brain regions following acute alcohol administration and during withdrawal. Local mechanisms for fine-tuning neuronal excitability via manipulation of neurosteroid synthesis exert predicted behavioral and electrophysiological responses on GABAAR-mediated inhibition. Collectively, targeting neurosteroidogenesis may be a beneficial treatment strategy for alcohol use disorders.
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20
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Synaptic adaptations in the central amygdala and hypothalamic paraventricular nucleus associated with protracted ethanol abstinence in male rhesus monkeys. Neuropsychopharmacology 2019; 44:982-993. [PMID: 30555160 PMCID: PMC6461779 DOI: 10.1038/s41386-018-0290-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/25/2018] [Accepted: 11/27/2018] [Indexed: 01/06/2023]
Abstract
Alcohol use disorder is a significant global burden. Stress has been identified as an etiological factor in the initiation and continuation of ethanol consumption. Understanding adaptations within stress circuitry is an important step toward novel treatment strategies. The effects of protracted abstinence following long-term ethanol self-administration on the central nucleus of the amygdala (CeA) and the hypothalamic paraventricular nucleus (PVN) were evaluated in male rhesus monkeys. Using whole-cell patch-clamp electrophysiology, inhibitory GABAergic transmission in the CeA and excitatory glutamatergic transmission in the PVN were measured. CeA neurons from abstinent drinkers displayed an elevated baseline spontaneous inhibitory postsynaptic current (sIPSC) frequency compared with controls, indicating increased presynaptic GABA release. Application of acute ethanol significantly increased the frequency of sIPSCs in controls, but not in abstinent drinkers, suggesting a tolerance to ethanol-enhanced GABA release in abstinent rhesus monkeys with a history of chronic ethanol self-administration and repeated abstinence. In the PVN, the frequency of spontaneous excitatory postsynaptic currents (sEPSC) was elevated in abstinent drinkers compared with controls, indicating increased presynaptic glutamate release. Notably, acute ethanol decreased presynaptic glutamate release onto parvocellular PVN neurons in both controls and abstinent drinkers, suggesting a lack of tolerance to acute ethanol among PVN neurons. These results are the first to demonstrate distinct synaptic adaptations and ethanol sensitivity in both the extrahypothalamic and hypothalamic stress circuits in abstinent rhesus males. Importantly, our findings describe adaptations in stress circuitry present in the brain at a state during abstinence, just prior to relapse to ethanol drinking.
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21
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van den Pol AN, Acuna C, Davis JN, Huang H, Zhang X. Defining the caudal hypothalamic arcuate nucleus with a focus on anorexic excitatory neurons. J Physiol 2019; 597:1605-1625. [PMID: 30618146 PMCID: PMC6418765 DOI: 10.1113/jp277152] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/03/2019] [Indexed: 01/11/2023] Open
Abstract
KEY POINTS Excitatory glutamate neurons are sparse in the rostral hypothalamic arcuate nucleus (ARC), the subregion that has received the most attention in the past. In striking contrast, excitatory neurons are far more common (by a factor of 10) in the caudal ARC, an area which has received relatively little attention. These glutamate cells may play a negative role in energy balance and food intake. They can show an increase in phosphorylated Stat-3 in the presence of leptin, are electrically excited by the anorectic neuromodulator cholecystokinin, and inhibited by orexigenic neuromodulators neuropeptide Y, met-enkephalin, dynorphin and the catecholamine dopamine. The neurons project local axonal connections that excite other ARC neurons including proopiomelanocortin neurons that can play an important role in obesity. These data are consistent with models suggesting that the ARC glutamatergic neurons may play both a rapid and a slower role in acting as anorectic neurons in CNS control of food intake and energy homeostasis. ABSTRACT Here we interrogate a unique class of excitatory neurons in the hypothalamic arcuate nucleus (ARC) that utilizes glutamate as a fast neurotransmitter using mice expressing GFP under control of the vesicular glutamate transporter 2 (vGluT2) promoter. These neurons show a unique distribution, synaptic characterization, cellular physiology and response to neuropeptides involved in energy homeostasis. Although apparently not previously appreciated, the caudal ARC showed a far greater density of vGluT2 cells than the rostral ARC, as seen in transgenic vGluT2-GFP mice and mRNA analysis. After food deprivation, leptin induced an increase in phosphorylated Stat-3 in vGluT2-positive neurons, indicating a response to hormonal cues of energy state. Based on whole-cell recording electrophysiology in brain slices, vGluT2 neurons were spontaneously active with a spike frequency around 2 Hz. vGluT2 cells were responsive to a number of neuropeptides related to energy homeostasis; they were excited by the anorectic peptide cholecystokinin, but inhibited by orexigenic neuropeptide Y, dynorphin and met-enkephalin, consistent with an anorexic role in energy homeostasis. Dopamine, associated with the hedonic aspect of enhancing food intake, inhibited vGluT2 neurons. Optogenetic excitation of vGluT2 cells evoked EPSCs in neighbouring neurons, indicating local synaptic excitation of other ARC neurons. Microdrop excitation of ARC glutamate cells in brain slices rapidly increased excitatory synaptic activity in anorexigenic proopiomelanocortin neurons. Together these data support the perspective that vGluT2 cells may be more prevalent in the ARC than previously appreciated, and play predominantly an anorectic role in energy metabolism.
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Affiliation(s)
| | - Claudio Acuna
- Department of NeurosurgeryYale University School of MedicineNew HavenCT06520USA
| | - John N. Davis
- Department of NeurosurgeryYale University School of MedicineNew HavenCT06520USA
| | - Hao Huang
- Department of NeurosurgeryYale University School of MedicineNew HavenCT06520USA
| | - Xiaobing Zhang
- Department of NeurosurgeryYale University School of MedicineNew HavenCT06520USA
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22
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Godoy-Reyes TM, Llopis-Lorente A, García-Fernández A, Gaviña P, Costero AM, Villalonga R, Sancenón F, Martínez-Máñez R. A l-glutamate-responsive delivery system based on enzyme-controlled self-immolative arylboronate-gated nanoparticles. Org Chem Front 2019. [DOI: 10.1039/c9qo00093c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Janus Au–mesoporous silica nanoparticles functionalized withl-glutamate oxidase and self-immolative arylboronate as al-glutamate-responsive delivery system.
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Affiliation(s)
- Tania M. Godoy-Reyes
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Antoni Llopis-Lorente
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Alba García-Fernández
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Pablo Gaviña
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Ana M. Costero
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Reynaldo Villalonga
- Nanosensors & Nanomachines Group
- Department of Analytical Chemistry
- Faculty of Chemistry
- Complutense University of Madrid
- 28040 Madrid
| | - Félix Sancenón
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
| | - Ramón Martínez-Máñez
- Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM)
- Universitat Politècnica de València-Univeritat de València
- Spain
- CIBER de Bioingenieria
- Biomateriales y Nanomedicina (CIBER-BBN)
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23
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Sunstrum JK, Inoue W. Heterosynaptic modulation in the paraventricular nucleus of the hypothalamus. Neuropharmacology 2018; 154:87-95. [PMID: 30408488 DOI: 10.1016/j.neuropharm.2018.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/18/2018] [Accepted: 11/03/2018] [Indexed: 12/21/2022]
Abstract
The stress response-originally described by Hans Selye as "the nonspecific response of the body to any demand made upon it"-is chiefly mediated by the hypothalamic-pituitary-adrenal (HPA) axis and is activated by diverse sensory stimuli that inform threats to homeostasis. The diversity of signals regulating the HPA axis is partly achieved by the complexity of afferent inputs that converge at the apex of the HPA axis: this apex is formed by a group of neurosecretory neurons that synthesize corticotropin-releasing hormone (CRH) in the paraventricular nucleus of the hypothalamus (PVN). The afferent synaptic inputs onto these PVN-CRH neurons originate from a number of brain areas, and PVN-CRH neurons respond to a long list of neurotransmitters/neuropeptides. Considering this complexity, an important question is how these diverse afferent signals independently and/or in concert influence the excitability of PVN-CRH neurons. While many of these inputs directly act on the postsynaptic PVN-CRH neurons for the summation of signals, accumulating data indicates that they also modulate each other's transmission in the PVN. This mode of transmission, termed heterosynaptic modulation, points to mechanisms through which the activity of a specific modulatory input (conveying a specific sensory signal) can up- or down-regulate the efficacy of other afferent synapses (mediating other stress modalities) depending on receptor expression for and spatial proximity to the heterosynaptic signals. Here, we review examples of heterosynaptic modulation in the PVN and discuss its potential role in the regulation of PVN-CRH neurons' excitability and resulting HPA axis activity. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Julia K Sunstrum
- Neuroscience Program, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Wataru Inoue
- Neuroscience Program, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada; Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada; Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
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24
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Le Tissier P, Fiordelisio Coll T, Mollard P. The Processes of Anterior Pituitary Hormone Pulse Generation. Endocrinology 2018; 159:3524-3535. [PMID: 30020429 DOI: 10.1210/en.2018-00508] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/11/2018] [Indexed: 12/16/2022]
Abstract
More than 60 years ago, Geoffrey Harris described his "neurohumoral theory," in which the regulation of pituitary hormone secretion was a "simple" hierarchal relationship, with the hypothalamus as the controller. In models based on this theory, the electrical activity of hypothalamic neurons determines the release of hypophysiotropic hormones into the portal circulation, and the pituitary simply responds with secretion of a pulse of hormone into the bloodstream. The development of methodologies allowing the monitoring of the activities of members of the hypothalamic-vascular-pituitary unit is increasingly allowing dissection of the mechanisms generating hypothalamic and pituitary pulses. These have revealed that whereas hypothalamic input is required, its role as a driver of pulsatile pituitary hormone secretion varies between pituitary axes. The organization of pituitary cells has a key role in the modification of their response to hypophysiotropic factors that can lead to a memory of previous demand and enhanced function. Feedback can lead to oscillatory hormone output that is independent of pulses of hypophysiotropic factors and instead, results from the temporal relationship between pituitary output and target organ response. Thus, the mechanisms underlying the generation of pulses cannot be generalized, and the circularity of feedforward and feedback interactions must be considered to understand both normal physiological function and pathology. We describe some examples of the clinical implications of recognizing the importance of the pituitary and target organs in pulse generation and suggest avenues for future research in both the short and long term.
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Affiliation(s)
- Paul Le Tissier
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Tatiana Fiordelisio Coll
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, University of Montpellier, Montpellier, France
- Laboratorio de Neuroendocrinología Comparada, Departamento de Ecología y Recursos Naturales, Biología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City, Distrito Federal, México
| | - Patrice Mollard
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, University of Montpellier, Montpellier, France
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25
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Salter EW, Sunstrum JK, Matovic S, Inoue W. Chronic stress dampens excitatory synaptic gain in the paraventricular nucleus of the hypothalamus. J Physiol 2018; 596:4157-4172. [PMID: 29901836 DOI: 10.1113/jp275669] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 06/03/2018] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Glutamatergic synaptic inputs to corticotrophin-releasing hormone (CRH) secreting neurons in the paraventricular nucleus of the hypothalamus (PVN) are required for stress-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis. These synapses also undergo stress-induced plasticity, thereby influencing HPA axis stress adaptation. By using patch clamp electrophysiology, we show that, in adult non-stressed mice, action potentials at these glutamatergic afferents elicit multiquantal transmission to the postsynaptic PVN-CRH neurons (i.e. synaptic multiplicity). Mechanistically, synaptic multiplicity results from multivesicular release at common synaptic sites, which is facilitated upon elevation of release probability, effectively increasing the upper limit of the dynamic range of synaptic transmission. Following chronic variable stress, functional PVN glutamate synapse number increases, although its synaptic multiplicity paradoxically decreases. These two contrasting synaptic changes can, respectively, increase the baseline excitatory drive while also limiting the capacity for potentiation, and may preferentially increase the baseline excitatory drive onto PVN-CRH neurons. ABSTRACT The activation of the hypothalamic-pituitary-adrenal (HPA) axis relies on excitation of neuroendocrine neurons in the paraventricular nucleus of the hypothalamus (PVN) that secrete corticotrophin-releasing hormone (CRH). Afferent glutamate synapses onto these PVN-CRH neurons convey critical excitatory inputs during stress, and also undergo stress-induced plasticity, highlighting their roles in both stress activation and adaptation of the HPA axis. In the present study, using whole-cell patch clamp recordings from PVN-CRH neurons in brain slices from adult mice, we found that the amplitude of action potential-dependent spontaneous EPSCs (sEPSCs) was larger than that of action potential independent miniature EPSCs (mEPSCs), suggesting that action potentials at individual axons recruited multiquantal transmission onto the same postsynaptic neurons (i.e. synaptic multiplicity). The large, putative multiquantal sEPSCs had fast rise times similar to mEPSCs, and were abolished by replacing extracellular Ca2+ with Sr2+ , indicating Ca2+ -dependent synchronous release of multiple vesicles. Application of a low affinity, fast dissociating competitive AMPA receptor antagonist γ-d-glutamylglycine revealed that synaptic multiplicity resulted from multivesicular release targeting a common population of postsynaptic receptors. High-frequency afferent stimulation facilitated synaptic multiplicity, effectively increasing the upper limit of the dynamic range of synaptic transmission. Finally, we found that chronic variable stress (CVS), a stress model known to cause basal HPA axis hyperactivity, increased sEPSCs frequency but paradoxically decreased synaptic multiplicity. These results suggest that the CVS-induced synaptic changes may elevate the baseline excitatory drive at the same time as limiting the capacity for potentiation, and may contribute to the basal HPA axis hyperactivity.
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Affiliation(s)
- Eric W Salter
- Neuroscience Program, University of Western Ontario, London, Ontario, Canada
| | - Julia K Sunstrum
- Neuroscience Program, University of Western Ontario, London, Ontario, Canada
| | - Sara Matovic
- Neuroscience Program, University of Western Ontario, London, Ontario, Canada
| | - Wataru Inoue
- Neuroscience Program, University of Western Ontario, London, Ontario, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.,Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
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26
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Zhu H, Wang N, Yao L, Chen Q, Zhang R, Qian J, Hou Y, Guo W, Fan S, Liu S, Zhao Q, Du F, Zuo X, Guo Y, Xu Y, Li J, Xue T, Zhong K, Song X, Huang G, Xiong W. Moderate UV Exposure Enhances Learning and Memory by Promoting a Novel Glutamate Biosynthetic Pathway in the Brain. Cell 2018; 173:1716-1727.e17. [PMID: 29779945 DOI: 10.1016/j.cell.2018.04.014] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 02/21/2018] [Accepted: 04/12/2018] [Indexed: 02/07/2023]
Abstract
Sunlight exposure is known to affect mood, learning, and cognition. However, the molecular and cellular mechanisms remain elusive. Here, we show that moderate UV exposure elevated blood urocanic acid (UCA), which then crossed the blood-brain barrier. Single-cell mass spectrometry and isotopic labeling revealed a novel intra-neuronal metabolic pathway converting UCA to glutamate (GLU) after UV exposure. This UV-triggered GLU synthesis promoted its packaging into synaptic vesicles and its release at glutamatergic terminals in the motor cortex and hippocampus. Related behaviors, like rotarod learning and object recognition memory, were enhanced after UV exposure. All UV-induced metabolic, electrophysiological, and behavioral effects could be reproduced by the intravenous injection of UCA and diminished by the application of inhibitor or short hairpin RNA (shRNA) against urocanase, an enzyme critical for the conversion of UCA to GLU. These findings reveal a new GLU biosynthetic pathway, which could contribute to some of the sunlight-induced neurobehavioral changes.
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Affiliation(s)
- Hongying Zhu
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China; Hefei National Laboratory for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China, 230026 Hefei, China
| | - Ning Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Lei Yao
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Qi Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Ran Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Junchao Qian
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 230031 Hefei, China
| | - Yiwen Hou
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Weiwei Guo
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Sijia Fan
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Siling Liu
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, 650223 Kunming, China
| | - Qiaoyun Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Feng Du
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Xin Zuo
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Yujun Guo
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Yan Xu
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Jiali Li
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, 650223 Kunming, China
| | - Tian Xue
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 200031 Shanghai, China
| | - Kai Zhong
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 200031 Shanghai, China; High Magnetic Field Laboratory, Chinese Academy of Sciences, 230031 Hefei, China
| | - Xiaoyuan Song
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China
| | - Guangming Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China, 230026 Hefei, China.
| | - Wei Xiong
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, School of Life Sciences, University of Science and Technology of China, 230026 Hefei, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 200031 Shanghai, China.
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27
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Johnson CS, Bains JS, Watts AG. Neurotransmitter diversity in pre-synaptic terminals located in the parvicellular neuroendocrine paraventricular nucleus of the rat and mouse hypothalamus. J Comp Neurol 2018; 526:1287-1306. [PMID: 29424419 DOI: 10.1002/cne.24407] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 01/24/2018] [Accepted: 01/25/2018] [Indexed: 02/02/2023]
Abstract
Virtually all rodent neuroendocrine corticotropin-releasing-hormone (CRH) neurons are in the dorsal medial parvicellular (mpd) part of the paraventricular nucleus of the hypothalamus (PVH). They form the final common pathway for adrenocortical stress responses. Their activity is controlled by sets of GABA-, glutamate-, and catecholamine-containing inputs arranged in an interactive pre-motor network. Defining the nature and arrangement of these inputs can help clarify how stressor type and intensity information is conveyed to neuroendocrine neurons. Here we use immunohistochemistry with high-resolution 3-dimensional image analyses to examine the arrangement of single- and co-occurring GABA, glutamate, and catecholamine markers in synaptophysin-defined pre-synaptic terminals in the PVHmpd of unstressed rats and Crh-IRES-Cre;Ai14 transgenic mice: respectively, vesicular glutamate transporter 2 (VGluT2), vesicular GABA transporter (VGAT), dopamine β-hydroxylase (DBH), and phenylethanolamine n-methyltransferase (PNMT). Just over half of all PVHmpd pre-synaptic terminals contain VGAT, with slightly less containing VGluT2. The vast majority of terminal appositions with mouse CRH neurons occur non-somatically. However, there are significantly more somatic VGAT than VGluT2 appositions. In the rat PVHmpd, about five times as many pre-synaptic terminals contain PNMT than DBH only. However, because epinephrine release has never been detected in the PVH, PNMT terminals may functionally be noradrenergic not adrenergic. PNMT and VGluT2 co-occur in some pre-synaptic terminals indicating the potential for co-transmission of glutamate and norepinephrine. Collectively, these results provide a structural basis for how GABA/glutamate/catecholamine interactions enable adrenocortical responses to fast-onset interosensory stimuli, and more broadly, how combinations of PVH neurotransmitters and neuromodulators interact dynamically to control adrenocortical activity.
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Affiliation(s)
- Caroline S Johnson
- The Department of Biological Sciences, USC Dornsife College of Letters, Arts, and Sciences, and Neuroscience, Graduate Program, University of Southern California, Los Angeles, California
| | - Jaideep S Bains
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, University of Calgary, Alberta, Canada
| | - Alan G Watts
- The Department of Biological Sciences, USC Dornsife College of Letters, Arts, and Sciences, and Neuroscience, Graduate Program, University of Southern California, Los Angeles, California
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28
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Huang MC, Chen LY, Chang HM, Liang XY, Chen CK, Cheng WJ, Xu K. Decreased Blood Levels of Oxytocin in Ketamine-Dependent Patients During Early Abstinence. Front Psychiatry 2018; 9:633. [PMID: 30534093 PMCID: PMC6275217 DOI: 10.3389/fpsyt.2018.00633] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 11/07/2018] [Indexed: 01/03/2023] Open
Abstract
Background: Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is a common drug of abuse worldwide. Existing evidence suggest a disruption of oxytocin system involves in the development of addiction. In this study, we aimed to investigate the role of oxytocin in ketamine addiction by measuring the blood oxytocin levels in ketamine-dependent (KD) patients. Methods: Sixty-five KD patients and 65 controls were enrolled. Fasting plasma levels of oxytocin were determined at baseline and 1 and 2 weeks after ketamine withdrawal. Ketamine use variables, Beck Depression Inventory, Beck Anxiety Inventory (BAI), Visual Analog Scale for craving, and Childhood Trauma Questionnaire-short form were assessed in KD patients. Results: KD patients had significantly lower levels of oxytocin at baseline compared to controls (5.89 ± 2.13 vs. 9.53 ± 4.17 ng/mL, P < 0.001). Oxytocin levels increased after one (6.74 ± 2.63, P < 0.002) and 2 weeks (6.89 ± 2.69, P = 0.01) of withdrawal in KD patient despite the levels were still lower than controls (P = 0.001 and 0.002, respectively). The clinical variables did not correlate with baseline oxytocin levels except BAI scores, which showed a negative correlation with the levels (r = -0.263; P = 0.039). Conclusion: We found a distinctively reduced oxytocin level in KD patients and the level did not normalize after early abstinence. Lower oxytocin might be associated with anxious phenotype of ketamine dependence. These results suggest that oxytocin system dysregulated following chronic ketamine abuse and might provide insight in evaluating the potential therapeutic use of oxytocin for treating ketamine dependence.
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Affiliation(s)
- Ming-Chyi Huang
- Department of Psychiatry, Taipei City Psychiatric Center, Taipei City Hospital, Taipei, Taiwan.,Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Psychiatric Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Lian-Yu Chen
- Department of Psychiatry, Taipei City Psychiatric Center, Taipei City Hospital, Taipei, Taiwan.,Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan
| | - Hu-Ming Chang
- Department of Psychiatry, Taipei City Psychiatric Center, Taipei City Hospital, Taipei, Taiwan
| | - Xiao-Yu Liang
- Department of Psychiatry, Yale University School of Medicine, New Heaven, CT, United States
| | - Chih-Ken Chen
- Department of Psychiatry, Chang Gung Memorial Hospital, Keelung, Taiwan.,Chang Gung University School of Medicine, Taoyuan, Taiwan
| | - Wan-Ju Cheng
- Department of Psychiatry, China Medical University Hospital, Taichung, Taiwan.,Department of Public Health, China Medical University, Taichung, Taiwan
| | - Ke Xu
- Department of Psychiatry, Yale University School of Medicine, New Heaven, CT, United States
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29
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Phumsatitpong C, Moenter SM. Estradiol-Dependent Stimulation and Suppression of Gonadotropin-Releasing Hormone Neuron Firing Activity by Corticotropin-Releasing Hormone in Female Mice. Endocrinology 2018; 159:414-425. [PMID: 29069304 PMCID: PMC5761586 DOI: 10.1210/en.2017-00747] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 10/17/2017] [Indexed: 11/19/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) neurons are the final central regulators of reproduction, integrating various inputs that modulate fertility. Stress typically inhibits reproduction but can be stimulatory; stress effects can also be modulated by steroid milieu. Corticotropin-releasing hormone (CRH) released during the stress response may suppress reproduction independent of downstream glucocorticoids. We hypothesized CRH suppresses fertility by decreasing GnRH neuron firing activity. To test this, mice were ovariectomized (OVX) and either implanted with an estradiol capsule (OVX+E) or not treated further to examine the influence of estradiol on GnRH neuron response to CRH. Targeted extracellular recordings were used to record firing activity from green fluorescent protein-identified GnRH neurons in brain slices before and during CRH treatment; recordings were done in the afternoon when estradiol has a positive feedback effect to increase GnRH neuron firing. In OVX mice, CRH did not affect the firing rate of GnRH neurons. In contrast, CRH exhibited dose-dependent stimulatory (30 nM) or inhibitory (100 nM) effects on GnRH neuron firing activity in OVX+E mice; both effects were reversible. The dose-dependent effects of CRH appear to result from activation of different receptor populations; a CRH receptor type-1 agonist increased firing activity in GnRH neurons, whereas a CRH receptor type-2 agonist decreased firing activity. CRH and specific agonists also differentially regulated short-term burst frequency and burst properties, including burst duration, spikes/burst, and/or intraburst interval. These results indicate that CRH alters GnRH neuron activity and that estradiol is required for CRH to exert both stimulatory and inhibitory effects on GnRH neurons.
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Affiliation(s)
- Chayarndorn Phumsatitpong
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
| | - Suzanne M. Moenter
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan 48109
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30
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Bai W, Zhou YG. Homeostasis of the Intraparenchymal-Blood Glutamate Concentration Gradient: Maintenance, Imbalance, and Regulation. Front Mol Neurosci 2017; 10:400. [PMID: 29259540 PMCID: PMC5723322 DOI: 10.3389/fnmol.2017.00400] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 11/20/2017] [Indexed: 12/25/2022] Open
Abstract
It is widely accepted that glutamate is the most important excitatory neurotransmitter in the central nervous system (CNS). However, there is also a large amount of glutamate in the blood. Generally, the concentration gradient of glutamate between intraparenchymal and blood environments is stable. However, this gradient is dramatically disrupted under a variety of pathological conditions, resulting in an amplifying cascade that causes a series of pathological reactions in the CNS and peripheral organs. This eventually seriously worsens a patient’s prognosis. These two “isolated” systems are rarely considered as a whole even though they mutually influence each other. In this review, we summarize what is currently known regarding the maintenance, imbalance and regulatory mechanisms that control the intraparenchymal-blood glutamate concentration gradient, discuss the interrelationships between these systems and further explore their significance in clinical practice.
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Affiliation(s)
- Wei Bai
- Molecular Biology Center, State Key Laboratory of Trauma, Burn, and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing, China
| | - Yuan-Guo Zhou
- Molecular Biology Center, State Key Laboratory of Trauma, Burn, and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing, China
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31
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Zhang M, Stern JE. Altered NMDA receptor-evoked intracellular Ca 2+ dynamics in magnocellular neurosecretory neurons of hypertensive rats. J Physiol 2017; 595:7399-7411. [PMID: 29034474 DOI: 10.1113/jp275169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/03/2017] [Indexed: 01/03/2023] Open
Abstract
KEY POINTS NMDA receptor (NMDAR)-mediated Ca2+ signalling plays a critical role in modulating hypothalamic neurosecretory function. However, whether an altered NMDAR-evoked changes in Ca2+ (NMDAR-ΔCa2+ ) signalling in magnocellular neurosecretory cells (MNCs) may contribute to neurohumoral activation during disease states is unknown. We show that activation of NMDARs evoked similar inward currents in MNCs of sham and renovascular hypertensive (RVH) rats. Despite this, a prolonged and larger NMDAR-ΔCa2+ response was observed in the latter. The exacerbated NMDAR-ΔCa2+ responses in MNCs of RVH rats affected both somatic and dendritic compartments. Inhibition of the endoplasmic reticulum sarcoendoplasmic reticulum calcium trasport ATPase (SERCA) pump prolonged NMDAR-ΔCa2+ responses in sham rats, but not in RVH rats. Our study supports an altered spatiotemporal dynamic of NMDAR-ΔCa2+ signalling in MNCs from RVH rats, partly due to blunted endoplasmic reticulum Ca2+ buffering capacity. ABSTRACT A growing body of evidence supports an elevated NMDA receptor (NMDAR)-mediated glutamate excitatory function in the supraoptic nucleus and paraventricular nucleus of hypertensive rats that contributes to neurohumoral activation in this disease. However, the precise mechanisms underlying altered NMDAR signalling in hypertension remain to be elucidated. In this study, we performed simultaneous electrophysiology and fast confocal Ca2+ imaging to determine whether altered NMDAR-mediated changes in intracellular Ca2+ levels (NMDAR-ΔCa2+ ) occurred in hypothalamic magnocellular neurosecretory cells (MNCs) in renovascular hypertensive (RVH) rats. We found that despite evoking a similar excitatory inward current, activation of NMDARs resulted in a larger and prolonged ΔCa2+ in MNCs from RVH rats. Changes in NMDAR-ΔCa2+ dynamics were observed both in somatic and dendritic compartments. Inhibition of the sarcoendoplasmic reticulum calcium trasport ATPase (SERCA) pump activity with thapsigargin prolonged NMDAR-ΔCa2+ responses in MNCs of sham rats, but this effect was occluded in RVH rats, thus equalizing the magnitude and time course of the NMDA-ΔCa2+ responses between the two experimental groups. Taken together, our results support (1) an exacerbated NMDAR-ΔCa2+ response in somatodendritic compartments of MNCs of RVH rats, and (2) that a blunted ER Ca2+ buffering capacity contributes to the altered NMDAR-ΔCa2+ dynamics in this condition. Thus, altered spatiotemporal dynamics of the NMDAR-ΔCa2+ response stands as an underlying mechanism contributing to neurohumoral activation in neurogenic hypertension.
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Affiliation(s)
- Meng Zhang
- Department of Physiology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
| | - Javier E Stern
- Department of Physiology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
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Zhang M, Biancardi VC, Stern JE. An increased extrasynaptic NMDA tone inhibits A-type K + current and increases excitability of hypothalamic neurosecretory neurons in hypertensive rats. J Physiol 2017; 595:4647-4661. [PMID: 28378360 PMCID: PMC5509869 DOI: 10.1113/jp274327] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 03/31/2017] [Indexed: 12/27/2022] Open
Abstract
KEY POINTS A functional coupling between extrasynaptic NMDA receptors (eNMDARs) and the A-type K+ current (IA ) influences homeostatic firing responses of magnocellular neurosecretory cells (MNCs) to a physiological challenge. However, whether an altered eNMDAR-IA coupling also contributes to exacerbated MNC activity and neurohumoral activation during disease states is unknown. We show that activation of eNMDARs by exogenously applied NMDA inhibited IA in MNCs obtained from sham, but not in MNCs from renovascular hypertensive (RVH) rats. Neither the magnitude of the exogenously evoked NMDA current nor the expression of NMDAR subunits were altered in RVH rats. Conversely, we found that a larger endogenous glutamate tone, which was not due to blunted glutamate transport activity, led to the sustained activation of eNMDARs that tonically inhibited IA , contributing in turn to higher firing activity in RVH rats. Our studies show that exacerbated activation of eNMDARs by endogenous glutamate contributes to tonic inhibition of IA and enhanced MNC excitability in RVH rats. ABSTRACT We recently showed that a functional coupling between extrasynaptic NMDA receptors (eNMDARs) and the A-type K+ current (IA ) influences the firing activity of hypothalamic magnocellular neurosecretory neurons (MNCs), as well as homeostatic adaptive responses to a physiological challenge. Here, we aimed to determine whether changes in the eNMDAR-IA coupling also contributed to exacerbated MNC activity during disease states. We used a combination of patch-clamp electrophysiology and real-time PCR in MNCs in sham and renovascular hypertensive (RVH) rats. Activation of eNMDARs by exogenously applied NMDA inhibited IA in sham rats, but this effect was largely blunted in RVH rats. The blunted response was not due to changes in eNMDAR expression and/or function, since neither NMDA current magnitude or reversal potential, nor the levels of NR1-NR2A-D subunit expression were altered in RVH rats. Conversely, we found a larger endogenous glutamate tone, resulting in the sustained activation of eNMDARs that tonically inhibited IA and contributed also to higher ongoing firing activity in RVH rats. The enhanced endogenous glutamate tone in RVH rats was not due to blunted glutamate transporter activity. Rather, a higher transporter activity was observed, which possibly acted as a compensatory mechanism in the face of the elevated endogenous tone. In summary, our studies indicate that an elevated endogenous glutamate tone results in an exacerbated activation of eNMDARs, which in turn contributes to diminished IA magnitude and increased firing activity of MNCs from hypertensive rats.
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Affiliation(s)
- Meng Zhang
- Department of PhysiologyMedical College of GeorgiaAugusta University1120 15th StreetAugustaGA30912USA
| | - Vinicia C. Biancardi
- Department of PhysiologyMedical College of GeorgiaAugusta University1120 15th StreetAugustaGA30912USA
| | - Javier E. Stern
- Department of PhysiologyMedical College of GeorgiaAugusta University1120 15th StreetAugustaGA30912USA
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Cote-Vélez A, Martínez Báez A, Lezama L, Uribe RM, Joseph-Bravo P, Charli JL. A screen for modulators reveals that orexin-A rapidly stimulates thyrotropin releasing hormone expression and release in hypothalamic cell culture. Neuropeptides 2017; 62:11-20. [PMID: 28173961 DOI: 10.1016/j.npep.2017.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/25/2017] [Accepted: 01/30/2017] [Indexed: 12/21/2022]
Abstract
In the paraventricular nucleus of the mammalian hypothalamus, hypophysiotropic thyrotropin releasing hormone (TRH) neurons integrate metabolic information and control the activity of the thyroid axis. Additional populations of TRH neurons reside in various hypothalamic areas, with poorly defined connections and functions, albeit there is evidence that some may be related to energy balance. To establish extracellular modulators of TRH hypothalamic neurons activity, we performed a screen of neurotransmitters effects in hypothalamic cultures. Cell culture conditions were chosen to facilitate the full differentiation of the TRH neurons; these conditions had permitted the characterization of the effects of known modulators of hypophysiotropic TRH neurons. The major end-point of the screen was Trh mRNA levels, since they are generally rapidly (0.5-3h) modified by synaptic inputs onto TRH neurons; in some experiments, TRH cell content or release was also analyzed. Various modulators, including histamine, serotonin, β-endorphin, met-enkephalin, and melanin concentrating hormone, had no effect. Glutamate, as well as ionotropic agonists (kainate and N-Methyl-d-aspartic acid), increased Trh mRNA levels. Baclofen, a GABAB receptor agonist, and dopamine enhanced Trh mRNA levels. An endocannabinoid receptor 1 inverse agonist promoted TRH release. Somatostatin increased Trh mRNA levels and TRH cell content. Orexin-A rapidly increased Trh mRNA levels, TRH cell content and release, while orexin-B decreased Trh mRNA levels. These data reveal unaccounted regulators, which exert potent effects on hypothalamic TRH neurons in vitro.
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Affiliation(s)
- Antonieta Cote-Vélez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Anabel Martínez Báez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Leticia Lezama
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Rosa María Uribe
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Patricia Joseph-Bravo
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico
| | - Jean-Louis Charli
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mor. 62271, Mexico.
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Cai W, Zhang K, Li P, Zhu L, Xu J, Yang B, Hu X, Lu Z, Chen J. Dysfunction of the neurovascular unit in ischemic stroke and neurodegenerative diseases: An aging effect. Ageing Res Rev 2017; 34:77-87. [PMID: 27697546 PMCID: PMC5384332 DOI: 10.1016/j.arr.2016.09.006] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/15/2016] [Accepted: 09/26/2016] [Indexed: 12/23/2022]
Abstract
Current understanding on the mechanisms of brain injury and neurodegeneration highlights an appreciation of multicellular interactions within the neurovascular unit (NVU), which include the evolution of blood-brain barrier (BBB) damage, neuronal cell death or degeneration, glial reaction, and immune cell infiltration. Aging is an important factor that influences the integrity of the NVU. The age-related physiological or pathological changes in the cellular components of the NVU have been shown to increase the vulnerability of the NVU to ischemia/reperfusion injury or neurodegeneration, and to result in deteriorated brain damage. This review describes the impacts of aging on each NVU component and discusses the mechanisms by which aging increases NVU sensitivity to stroke and neurodegenerative diseases. Prophylactic or therapeutic perspectives that may delay or diminish aging and thus prevent the incidence of these neurological disorders will also be reviewed.
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Affiliation(s)
- Wei Cai
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, 510630, China; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Kai Zhang
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Peiying Li
- Department of Anesthesiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Ling Zhu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Department of Anesthesiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Jing Xu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Boyu Yang
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Xiaoming Hu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Zhengqi Lu
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, 510630, China.
| | - Jun Chen
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA; Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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Qiu J, Nestor CC, Zhang C, Padilla SL, Palmiter RD, Kelly MJ, Rønnekleiv OK. High-frequency stimulation-induced peptide release synchronizes arcuate kisspeptin neurons and excites GnRH neurons. eLife 2016; 5:e16246. [PMID: 27549338 PMCID: PMC4995096 DOI: 10.7554/elife.16246] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/18/2016] [Indexed: 12/19/2022] Open
Abstract
Kisspeptin (Kiss1) and neurokinin B (NKB) neurocircuits are essential for pubertal development and fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (Kiss1(ARH)) co-express Kiss1, NKB, dynorphin and glutamate and are postulated to provide an episodic, excitatory drive to gonadotropin-releasing hormone 1 (GnRH) neurons, the synaptic mechanisms of which are unknown. We characterized the cellular basis for synchronized Kiss1(ARH) neuronal activity using optogenetics, whole-cell electrophysiology, molecular pharmacology and single cell RT-PCR in mice. High-frequency photostimulation of Kiss1(ARH) neurons evoked local release of excitatory (NKB) and inhibitory (dynorphin) neuropeptides, which were found to synchronize the Kiss1(ARH) neuronal firing. The light-evoked synchronous activity caused robust excitation of GnRH neurons by a synaptic mechanism that also involved glutamatergic input to preoptic Kiss1 neurons from Kiss1(ARH) neurons. We propose that Kiss1(ARH) neurons play a dual role of driving episodic secretion of GnRH through the differential release of peptide and amino acid neurotransmitters to coordinate reproductive function.
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Affiliation(s)
- Jian Qiu
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
| | - Casey C Nestor
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
| | - Chunguang Zhang
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
| | - Stephanie L Padilla
- Department of Biochemistry, Howard Hughes Medical Institute, University of Washington, Seattle, United States
| | - Richard D Palmiter
- Department of Biochemistry, Howard Hughes Medical Institute, University of Washington, Seattle, United States
| | - Martin J Kelly
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, United States
| | - Oline K Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, United States
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, United States
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Brunetti L, Di Nisio C, Orlando G, Ferrante C, Vacca M. The Regulation of Feeding: A Cross Talk between Peripheral and Central Signalling. Int J Immunopathol Pharmacol 2016; 18:201-12. [PMID: 15888244 DOI: 10.1177/039463200501800203] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Feeding and energy expenditures are modulated by the interplay of hormones and neurotransmitters in the central nervous system (CNS), where the hypothalamus plays a pivotal role in the transduction of peripheral afferents into satiety and feeding signals. Aminergic neurotransmitters such as dopamine (DA), norepinephrine (NE) and serotonin (5-hydroxytryptamine, 5-HT) are historically considered to play a key role, but a number of peptides are involved in finely tuning feeding regulation. This review summarizes the current understanding of the CNS mechanisms of orexigenic peptides, such as neuropeptide Y, orexins, and ghrelin, as well as anorectic peptides, such as leptin, neurotensin (NT), cocaine- and amphetamine regulated transcript (CART) peptide, thyrotropin-releasing hormone (TRH), corticotropin-releasing hormone (CRH), urocortin, amylin.
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Affiliation(s)
- L Brunetti
- Department of Drug Sciences, G. D'Annunzio University, Chieti, Italy
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Pai YH, Lim CS, Park KA, Cho HS, Lee GS, Shin YS, Kim HW, Jeon BH, Yoon SH, Park JB. Facilitation of AMPA receptor-mediated steady-state current by extrasynaptic NMDA receptors in supraoptic magnocellular neurosecretory cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:425-32. [PMID: 27382359 PMCID: PMC4930911 DOI: 10.4196/kjpp.2016.20.4.425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/06/2016] [Accepted: 06/09/2016] [Indexed: 01/02/2023]
Abstract
In addition to classical synaptic transmission, information is transmitted between cells via the activation of extrasynaptic receptors that generate persistent tonic current in the brain. While growing evidence supports the presence of tonic NMDA current (INMDA) generated by extrasynaptic NMDA receptors (eNMDARs), the functional significance of tonic INMDA in various brain regions remains poorly understood. Here, we demonstrate that activation of eNMDARs that generate INMDA facilitates the α-amino-3-hydroxy-5-methylisoxazole-4-proprionate receptor (AMPAR)-mediated steady-state current in supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs). In low-Mg2+ artificial cerebrospinal fluid (aCSF), glutamate induced an inward shift in Iholding (IGLU) at a holding potential (Vholding) of –70 mV which was partly blocked by an AMPAR antagonist, NBQX. NBQX-sensitive IGLU was observed even in normal aCSF at Vholding of –40 mV or –20 mV. IGLU was completely abolished by pretreatment with an NMDAR blocker, AP5, under all tested conditions. AMPA induced a reproducible inward shift in Iholding (IAMPA) in SON MNCs. Pretreatment with AP5 attenuated IAMPA amplitudes to ~60% of the control levels in low-Mg2+ aCSF, but not in normal aCSF at Vholding of –70 mV. IAMPA attenuation by AP5 was also prominent in normal aCSF at depolarized holding potentials. Memantine, an eNMDAR blocker, mimicked the AP5-induced IAMPA attenuation in SON MNCs. Finally, chronic dehydration did not affect IAMPA attenuation by AP5 in the neurons. These results suggest that tonic INMDA, mediated by eNMDAR, facilitates AMPAR function, changing the postsynaptic response to its agonists in normal and osmotically challenged SON MNCs.
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Affiliation(s)
- Yoon Hyoung Pai
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Chae Seong Lim
- Department of Anesthesiology & Pain Medicine, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Kyung-Ah Park
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Hyun Sil Cho
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Gyu-Seung Lee
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Yong Sup Shin
- Department of Anesthesiology & Pain Medicine, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Hyun-Woo Kim
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Byeong Hwa Jeon
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Seok Hwa Yoon
- Department of Anesthesiology & Pain Medicine, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
| | - Jin Bong Park
- Department of Physiology, Brain Research Institute, School of Medicine, Chungnam National University, Daejeon 35015, Korea
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Reis WL, Biancardi VC, Zhou Y, Stern JE. A Functional Coupling Between Carbon Monoxide and Nitric Oxide Contributes to Increased Vasopressin Neuronal Activity in Heart Failure rats. Endocrinology 2016; 157:2052-66. [PMID: 26982634 PMCID: PMC4870874 DOI: 10.1210/en.2015-1958] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Despite the pathophysiological importance of neurohumoral activation in patients with heart failure (HF), the precise underlying mechanisms contributing to elevated vasopressin (VP) activation in HF remains unknown. Carbon monoxide (CO) is a gaseous neurotransmitter in the central nervous system that stimulates VP neuronal firing activity. Recently, we showed that the excitatory effect of CO on VP neurons in the hypothalamic paraventricular nucleus (PVN) was mediated by inhibition of nitric oxide (NO). Given that previous studies showed that VP neuronal activity is enhanced, whereas NO inhibitory signaling is blunted in HF rats, we tested whether an enhanced endogenous CO availability within the PVN contributes to elevated VP neuronal activity and blunted NO signaling in HF rats. We found that both haeme-oxygenase 1 (the CO-synthesizing enzyme) protein and mRNA expression levels were enhanced in the PVN of HF compared with sham rats (∼18% and ∼38%, respectively). We report that in sham rats, bath application of a CO donor (tricarbonyldichlororuthenium dimer) increased the firing activity of identified PVN VP neurons (P < .05), whereas inhibition of endogenous CO production (Tin-protoporphyrin IX [SnPP]) failed to affect neuronal activity. In HF rats, however, SnPP decreased VP activity (P < .05), an effect that was occluded by previous NO synathase blockade NG-nitro-larginine methyl ester. Finally, we found that SnPP increased the mean frequency of γ-aminobutyric acid inhibitory postsynaptic currents in VP neurons in HF (P < .05) but not sham rats. Our results support an enhanced endogenous CO excitatory signaling in VP neurons, which likely contributes to blunted NO and γ-aminobutyric acid inhibitory function in HF rats.
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Affiliation(s)
- Wagner L Reis
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia 30912
| | - Vinicia C Biancardi
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia 30912
| | - Yiqiang Zhou
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia 30912
| | - Javier E Stern
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia 30912
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Nestor CC, Qiu J, Padilla SL, Zhang C, Bosch MA, Fan W, Aicher SA, Palmiter RD, Rønnekleiv OK, Kelly MJ. Optogenetic Stimulation of Arcuate Nucleus Kiss1 Neurons Reveals a Steroid-Dependent Glutamatergic Input to POMC and AgRP Neurons in Male Mice. Mol Endocrinol 2016; 30:630-44. [PMID: 27093227 DOI: 10.1210/me.2016-1026] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Kisspeptin (Kiss1) neurons are essential for reproduction, but their role in the control of energy balance and other homeostatic functions remains unclear. Proopiomelanocortin (POMC) and agouti-related peptide (AgRP) neurons, located in the arcuate nucleus (ARC) of the hypothalamus, integrate numerous excitatory and inhibitory inputs to ultimately regulate energy homeostasis. Given that POMC and AgRP neurons are contacted by Kiss1 neurons in the ARC (Kiss1(ARC)) and they express androgen receptors, Kiss1(ARC) neurons may mediate the orexigenic action of testosterone via POMC and/or AgRP neurons. Quantitative PCR analysis of pooled Kiss1(ARC) neurons revealed that mRNA levels for Kiss1 and vesicular glutamate transporter 2 were higher in castrated male mice compared with gonad-intact males. Single-cell RT-PCR analysis of yellow fluorescent protein (YFP) ARC neurons harvested from males injected with AAV1-EF1α-DIO-ChR2:YFP revealed that 100% and 88% expressed mRNAs for Kiss1 and vesicular glutamate transporter 2, respectively. Whole-cell, voltage-clamp recordings from nonfluorescent postsynaptic ARC neurons showed that low frequency photo-stimulation (0.5 Hz) of Kiss1-ChR2:YFP neurons elicited a fast glutamatergic inward current in POMC and AgRP neurons. Paired-pulse, photo-stimulation revealed paired-pulse depression, which is indicative of greater glutamate release, in the castrated male mice compared with gonad-intact male mice. Group I and group II metabotropic glutamate receptor agonists depolarized and hyperpolarized POMC and AgRP neurons, respectively, which was mimicked by high frequency photo-stimulation (20 Hz) of Kiss1(ARC) neurons. Therefore, POMC and AgRP neurons receive direct steroid- and frequency-dependent glutamatergic synaptic input from Kiss1(ARC) neurons in male mice, which may be a critical pathway for Kiss1 neurons to help coordinate energy homeostasis and reproduction.
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Affiliation(s)
- Casey C Nestor
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Jian Qiu
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Stephanie L Padilla
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Chunguang Zhang
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Martha A Bosch
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Wei Fan
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Sue A Aicher
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Richard D Palmiter
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Oline K Rønnekleiv
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
| | - Martin J Kelly
- Department of Physiology and Pharmacology (C.CN., J.Q., C.Z., M.A.B., S.A.A., O.K.R., M.J.K.) and Anesthesiology and Perioperative Medicine and Knight Cardiovascular Institute (W.F.), Oregon Health & Science University, Portland, Oregon 97239; Division of Neuroscience (O.K.R., M.J.K.), Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006; and Howard Hughes Medical Institute (S.L.P., R.D.P.), University of Washington, Seattle, Washington 98195
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40
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Augustine RA, Bouwer GT, Seymour AJ, Grattan DR, Brown CH. Reproductive Regulation of Gene Expression in the Hypothalamic Supraoptic and Paraventricular Nuclei. J Neuroendocrinol 2016; 28. [PMID: 26670189 DOI: 10.1111/jne.12350] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 11/27/2022]
Abstract
Oxytocin secretion is required for successful reproduction. Oxytocin is synthesised by magnocellular neurones of the hypothalamic supraoptic and paraventricular nuclei and the physiological demand for oxytocin synthesis and secretion is increased for birth and lactation. Therefore, we used a polymerase chain reaction (PCR) array screen to determine whether genes that might be important for synthesis and/or secretion of oxytocin are up- or down-regulated in the supraoptic and paraventricular nuclei of late-pregnant and lactating rats, compared to virgin rats. We then validated the genes that were most highly regulated using real time-quantitative PCR. Among the most highly regulated genes were those that encode for suppressors of cytokine signalling, which are intracellular inhibitors of prolactin signalling. Prolactin receptor activation changes gene expression via phosphorylation of signal transducer and activator of transcription 5 (STAT5). Using double-label immunohistochemistry, we found that phosphorylated STAT5 was expressed in almost all oxytocin neurones of late-pregnant and lactating rats but was almost absent from oxytocin neurones of virgin rats. We conclude that increased prolactin activation of oxytocin neurones might contribute to the changes in gene expression by oxytocin neurones required for normal birth and lactation.
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Affiliation(s)
- R A Augustine
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - G T Bouwer
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - A J Seymour
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - D R Grattan
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - C H Brown
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
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41
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Busnardo C, Crestani CC, Fassini A, Resstel LBM, Corrêa FMA. NMDA and non-NMDA glutamate receptors in the paraventricular nucleus of the hypothalamus modulate different stages of hemorrhage-evoked cardiovascular responses in rats. Neuroscience 2016; 320:149-59. [PMID: 26861418 DOI: 10.1016/j.neuroscience.2016.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/18/2016] [Accepted: 02/01/2016] [Indexed: 10/22/2022]
Abstract
Here we report the involvement of N-Methyl-d-Aspartate (NMDA) and non-NMDA glutamate receptors from the paraventricular nucleus of the hypothalamus (PVN) in the mediation of cardiovascular changes observed during hemorrhage and post-bleeding periods. In addition, the present study provides further evidence of the involvement of circulating vasopressin and cardiac sympathetic activity in cardiovascular responses to hemorrhage. Systemic treatment with the V1-vasopressin receptor antagonist dTyr(CH2)5(Me)AVP (50 μg/kg, i.v.) increased the latency to the onset of hypotension during hemorrhage and slowed post-bleeding recovery of blood pressure. Systemic treatment with the β1-adrenergic receptor antagonist atenolol (1 mg/kg, i.v.) also increased the latency to the onset of hypotension during hemorrhage. Moreover, atenolol reversed the hemorrhage-induced tachycardia into bradycardia. Bilateral microinjection of the selective NMDA glutamate receptor antagonist LY235959 (2 nmol/100 nL) into the PVN blocked the hypotensive response to hemorrhage and reduced the tachycardia during the post-hemorrhage period. Systemic treatment with dTyr(CH2)5(Me)AVP inhibited the effect of LY235959 on hemorrhage-induced hypotension, without affecting the post-bleeding tachycardia. PVN treatment with the selective non-NMDA receptor antagonist NBQX (2 nmol/100 nL) reduced the recovery of blood pressure to normal levels in the post-bleeding phase and reduced hemorrhage-induced tachycardia. Combined blockade of both NMDA and non-NMDA glutamate receptors in the PVN completely abolished the hypotensive response in the hemorrhage period and reduced the tachycardiac response in the post-hemorrhage period. These results indicate that local PVN glutamate neurotransmission is involved in the neural pathway mediating cardiovascular responses to hemorrhage, via an integrated control involving autonomic nervous system activity and vasopressin release into the circulation.
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Affiliation(s)
- C Busnardo
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
| | - C C Crestani
- School of Pharmaceutical Sciences, Univ. Estadual Paulista-UNESP, Araraquara, SP, Brazil
| | - A Fassini
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - L B M Resstel
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - F M A Corrêa
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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42
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Bains JS, Wamsteeker Cusulin JI, Inoue W. Stress-related synaptic plasticity in the hypothalamus. Nat Rev Neurosci 2015; 16:377-88. [PMID: 26087679 DOI: 10.1038/nrn3881] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stress necessitates an immediate engagement of multiple neural and endocrine systems. However, exposure to a single stressor causes adaptive changes that modify responses to subsequent stressors. Recent studies examining synapses onto neuroendocrine cells in the paraventricular nucleus of the hypothalamus demonstrate that stressful experiences leave indelible marks that alter the ability of these synapses to undergo plasticity. These adaptations include a unique form of metaplasticity at glutamatergic synapses, bidirectional changes in endocannabinoid signalling and bidirectional changes in strength at GABAergic synapses that rely on distinct temporal windows following stress. This rich repertoire of plasticity is likely to represent an important building block for dynamic, experience-dependent modulation of neuroendocrine stress adaptation.
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Affiliation(s)
- Jaideep S Bains
- Hotchkiss Brain Institute and the Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Jaclyn I Wamsteeker Cusulin
- Hotchkiss Brain Institute and the Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Wataru Inoue
- Hotchkiss Brain Institute and the Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
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43
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Abstract
Prolactin (PRL) released from lactotrophs of the anterior pituitary gland in response to the suckling by the offspring is the major hormonal signal responsible for stimulation of milk synthesis in the mammary glands. PRL secretion is under chronic inhibition exerted by dopamine (DA), which is released from neurons of the arcuate nucleus of the hypothalamus into the hypophyseal portal vasculature. Suckling by the young activates ascending systems that decrease the release of DA from this system, resulting in enhanced responsiveness to one or more PRL-releasing hormones, such as thyrotropin-releasing hormone. The neuropeptide oxytocin (OT), synthesized in magnocellular neurons of the hypothalamic supraoptic, paraventricular, and several accessory nuclei, is responsible for contracting the myoepithelial cells of the mammary gland to produce milk ejection. Electrophysiological recordings demonstrate that shortly before each milk ejection, the entire neurosecretory OT population fires a synchronized burst of action potentials (the milk ejection burst), resulting in release of OT from nerve terminals in the neurohypophysis. Both of these neuroendocrine systems undergo alterations in late gestation that prepare them for the secretory demands of lactation, and that reduce their responsiveness to stimuli other than suckling, especially physical stressors. The demands of milk synthesis and release produce a condition of negative energy balance in the suckled mother, and, in laboratory rodents, are accompanied by a dramatic hyperphagia. The reduction in secretion of the adipocyte hormone, leptin, a hallmark of negative energy balance, may be an important endocrine signal to hypothalamic systems that integrate lactation-associated food intake with neuroendocrine systems.
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Affiliation(s)
- William R Crowley
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah Health Sciences Center, Salt Lake City, Utah
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44
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Abstract
The Na-K-2Cl cotransporter 2 (NKCC2) was thought to be kidney specific. Here we show expression in the brain hypothalamo-neurohypophyseal system (HNS), wherein upregulation follows osmotic stress. The HNS controls osmotic stability through the synthesis and release of the neuropeptide hormone, arginine vasopressin (AVP). AVP travels through the bloodstream to the kidney, where it promotes water conservation. Knockdown of HNS NKCC2 elicited profound effects on fluid balance following ingestion of a high-salt solution-rats produced significantly more urine, concomitant with increases in fluid intake and plasma osmolality. Since NKCC2 is the molecular target of the loop diuretics bumetanide and furosemide, we asked about their effects on HNS function following disturbed water balance. Dehydration-evoked GABA-mediated excitation of AVP neurons was reversed by bumetanide, and furosemide blocked AVP release, both in vivo and in hypothalamic explants. Thus, NKCC2-dependent brain mechanisms that regulate osmotic stability are disrupted by loop diuretics in rats.
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45
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Choudhary RC, Sharma RK, Gulati K, Ravi K. Role of the paraventricular nucleus in the reflex diuresis to pulmonary lymphatic obstruction in rabbits. Can J Physiol Pharmacol 2015; 94:18-27. [PMID: 26497164 DOI: 10.1139/cjpp-2015-0109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The changes in urine flow and renal sympathetic nerve activity (RSNA) due to pulmonary lymphatic obstruction (PLO) were examined in anesthetized, artificially ventilated New Zealand white rabbits. PLO was produced by pressurizing an isolated pouch created in the right external jugular vein at the points of entry of the right lymphatic ducts. During this maneuver, urine flow increased from 8.5 ± 0.3 mL/10 min to 12 ± 0.5 mL/10 min (P < 0.0001) and RSNA increased from 24.0 ± 4 to 40.0 ± 5 μV·s (P < 0.0001). Bilateral lesioning of the paraventricular nucleus (PVN) of the hypothalamus or cervical vagotomy abolished these responses. PLO increased c-fos gene expression in the PVN. The increase in urine flow due to PLO was attenuated by muscimol and abolished by kynurenic acid microinjections into the PVN. The results show that (i) neurons in the PVN are an important relay site in the reflex arc, which is activated by PLO; and (ii) this activation is regulated by glutamatergic and partly by GABAergic input to the PVN.
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Affiliation(s)
- Rishabh Charan Choudhary
- a Department of Physiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Ravindra Kumar Sharma
- a Department of Physiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Kavita Gulati
- b Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Krishnan Ravi
- a Department of Physiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
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Qiu J, Kleineidam A, Gouraud S, Yao ST, Greenwood M, Hoe SZ, Hindmarch C, Murphy D. The use of protein-DNA, chromatin immunoprecipitation, and transcriptome arrays to describe transcriptional circuits in the dehydrated male rat hypothalamus. Endocrinology 2014; 155:4380-90. [PMID: 25144923 PMCID: PMC4256826 DOI: 10.1210/en.2014-1448] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The supraoptic nucleus (SON) of the hypothalamus is responsible for maintaining osmotic stability in mammals through its elaboration of the antidiuretic hormone arginine vasopressin. Upon dehydration, the SON undergoes a function-related plasticity, which includes remodeling of morphology, electrical properties, and biosynthetic activity. This process occurs alongside alterations in steady state transcript levels, which might be mediated by changes in the activity of transcription factors. In order to identify which transcription factors might be involved in changing patterns of gene expression, an Affymetrix protein-DNA array analysis was carried out. Nuclear extracts of SON from dehydrated and control male rats were analyzed for binding to the 345 consensus DNA transcription factor binding sequences of the array. Statistical analysis revealed significant changes in binding to 26 consensus elements, of which EMSA confirmed increased binding to signal transducer and activator of transcription (Stat) 1/Stat3, cellular Myelocytomatosis virus-like cellular proto-oncogene (c-Myc)-Myc-associated factor X (Max), and pre-B cell leukemia transcription factor 1 sequences after dehydration. Focusing on c-Myc and Max, we used quantitative PCR to confirm previous transcriptomic analysis that had suggested an increase in c-Myc, but not Max, mRNA levels in the SON after dehydration, and we demonstrated c-Myc- and Max-like immunoreactivities in SON arginine vasopressin-expressing cells. Finally, by comparing new data obtained from Roche-NimbleGen chromatin immunoprecipitation arrays with previously published transcriptomic data, we have identified putative c-Myc target genes whose expression changes in the SON after dehydration. These include known c-Myc targets, such as the Slc7a5 gene, which encodes the L-type amino acid transporter 1, ribosomal protein L24, histone deactylase 2, and the Rat sarcoma proto-oncogene (Ras)-related nuclear GTPase.
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Affiliation(s)
- Jing Qiu
- School of Clinical Sciences (J.Q., A.K., S.G., S.T.Y., M.G., C.H., D.M.), University of Bristol, Bristol BS1 3NY, United Kingdom; and Department of Physiology (S.Z.H., C.H., D.M.), Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
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47
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Lyons DJ, Broberger C. TIDAL WAVES: Network mechanisms in the neuroendocrine control of prolactin release. Front Neuroendocrinol 2014; 35:420-38. [PMID: 24561279 DOI: 10.1016/j.yfrne.2014.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 12/22/2013] [Accepted: 02/10/2014] [Indexed: 11/19/2022]
Abstract
Neuroendocrine tuberoinfundibular dopamine (TIDA) neurons tonically inhibit pituitary release of the hormone, prolactin. Through the powerful actions of prolactin in promoting lactation and maternal behaviour while suppressing sexual drive and fertility, TIDA neurons play a key role in reproduction. We summarize insights from recent in vitro studies into the membrane properties and network behaviour of TIDA neurons including the observations that TIDA neurons exhibit a robust oscillation that is synchronized between cells and depends on intact gap junction communication. Comparisons are made with phasic firing patterns in other neuronal populations. Modulators involved in the control of lactation - including serotonin, thyrotropin-releasing hormone and prolactin itself - have been shown to change the electrical behaviour of TIDA cells. We propose that TIDA discharge mode may play a central role in tuning the amount of dopamine delivered to the pituitary and hence circulating prolactin concentrations in different reproductive states and pathological conditions.
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Affiliation(s)
- David J Lyons
- Dept. of Neuroscience, Karolinska Institutet, Retzius v. 8, 171 77 Stockholm, Sweden
| | - Christian Broberger
- Dept. of Neuroscience, Karolinska Institutet, Retzius v. 8, 171 77 Stockholm, Sweden.
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48
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Stimulation of dopamine D4 receptors in the paraventricular nucleus of the hypothalamus of male rats induces hyperphagia: Involvement of glutamate. Physiol Behav 2014; 133:272-81. [DOI: 10.1016/j.physbeh.2014.04.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 04/29/2014] [Indexed: 11/18/2022]
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49
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Naskar K, Stern JE. A functional coupling between extrasynaptic NMDA receptors and A-type K+ channels under astrocyte control regulates hypothalamic neurosecretory neuronal activity. J Physiol 2014; 592:2813-27. [PMID: 24835172 DOI: 10.1113/jphysiol.2014.270793] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Neuronal activity is controlled by a fine-tuned balance between intrinsic properties and extrinsic synaptic inputs. Moreover, neighbouring astrocytes are now recognized to influence a wide spectrum of neuronal functions. Yet, how these three key factors act in concert to modulate and fine-tune neuronal output is not well understood. Here, we show that in rat hypothalamic magnocellular neurosecretory cells (MNCs), glutamate NMDA receptors (NMDARs) are negatively coupled to the transient, voltage-gated A-type K(+) current (IA). We found that activation of NMDARs by extracellular glutamate levels influenced by astrocyte glutamate transporters resulted in a significant inhibition of IA. The NMDAR-IA functional coupling resulted from activation of extrasynaptic NMDARs, was calcium- and protein kinase C-dependent, and involved enhanced steady-state, voltage-dependent inactivation of IA. The NMDAR-IA coupling diminished the latency to the first evoked spike in response to membrane depolarization and increased the total number of evoked action potentials, thus strengthening the neuronal input/output function. Finally, we found a blunted NMDA-mediated inhibition of IA in dehydrated rats. Together, our findings support a novel signalling mechanism that involves a functional coupling between extrasynaptic NMDARs and A-type K(+) channels, which is influenced by local astrocytes. We show this signalling complex to play an important role in modulating hypothalamic neuronal excitability, which may contribute to adaptive responses during a sustained osmotic challenge such as dehydration.
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Affiliation(s)
- Krishna Naskar
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, GA, 30912, USA
| | - Javier E Stern
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, GA, 30912, USA
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50
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Meza-Herrera CA, Calderón-Leyva G, Soto-Sanchez MJ, Serradilla JM, García-Martinez A, Mellado M, Veliz-Deras FG. Glutamate supply positively affects serum cholesterol concentrations without increases in total protein and urea around the onset of puberty in goats. Anim Reprod Sci 2014; 147:106-11. [PMID: 24811839 DOI: 10.1016/j.anireprosci.2014.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 04/04/2014] [Accepted: 04/06/2014] [Indexed: 11/24/2022]
Abstract
Different neurotransmitter and neuromodulatory systems regulate synthesis and secretion of GnRH. Whereas the endocrine and neural systems are activated in response to the metabolic status and the circulating levels of specific blood metabolites, glutamate receptors have been reported at hepatic level. This study evaluated the possible effect of glutamate supplementation upon changes in serum concentrations across time for total protein (TP), urea (UR) and cholesterol (CL) around the onset of puberty in goats. Prepuberal female goats (n=18) were randomly assigned to: (1) excitatory amino acids group, GLUT, n=10; 16.52±1.04kg live weight (LW), 3.4±0.12 body condition score (BCS) receiving an i.v. infusion of 7mgkg(-1) LW of l-glutamate, and (2) Control group, CONT, n=8; 16.1±1.04kg LW, 3.1±0.12 BCS. General averages for LW (23.2±0.72kg), BCS (3.37±0.10 units), serum TP (65.28±2.46mgdL(-1)), UR (23.42±0.95mgdL(-1)), CL (77.89±1.10mgdL(-1)) as well as the serum levels for TP and UR across time did not differ (P>0.05) between treatments. However, while GLUT positively affected (P<0.05) both the onset (207±9 vs. 225±12 d) and the percentage (70 vs. 25%) of females showing puberty, a treatment×time interaction effect (P<0.05) was observed in the GLUT group, with increases in serum cholesterol, coincident with the onset of puberty. Therefore, in peripuberal glutamate supplemented goats, serum cholesterol profile could act as a metabolic modulator for the establishment of puberty, denoting also a potential role of glutamate as modulator of lipid metabolism.
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Affiliation(s)
- C A Meza-Herrera
- Universidad Autónoma Chapingo, Unidad Regional Universitaria de Zonas Áridas, A.P. No. 8, Bermejillo, Durango, 35230, Mexico.
| | - G Calderón-Leyva
- Universidad Autónoma Chapingo, Unidad Regional Universitaria de Zonas Áridas, A.P. No. 8, Bermejillo, Durango, 35230, Mexico
| | - M J Soto-Sanchez
- Universidad Autónoma Chapingo, Unidad Regional Universitaria de Zonas Áridas, A.P. No. 8, Bermejillo, Durango, 35230, Mexico
| | - J M Serradilla
- Universidad de Córdoba, Departamento de Producción Animal, Campus de Rabanales, Ctra. Madrid-Cádiz, km 396, Córdoba, 14071, Spain
| | - A García-Martinez
- Universidad de Córdoba, Departamento de Producción Animal, Campus de Rabanales, Ctra. Madrid-Cádiz, km 396, Córdoba, 14071, Spain
| | - M Mellado
- Universidad Autónoma Agraria Antonio Narro, Periférico Raúl López Sánchez & Carretera a Santa Fe, Torreón, Coahuila, 27054, Mexico
| | - F G Veliz-Deras
- Universidad Autónoma Agraria Antonio Narro, Periférico Raúl López Sánchez & Carretera a Santa Fe, Torreón, Coahuila, 27054, Mexico
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