1
|
Khom S, Rodriguez L, Gandhi P, Kirson D, Bajo M, Oleata CS, Vendruscolo LF, Mason BJ, Roberto M. Alcohol dependence and withdrawal increase sensitivity of central amygdalar GABAergic synapses to the glucocorticoid receptor antagonist mifepristone in male rats. Neurobiol Dis 2022; 164:105610. [PMID: 34995754 PMCID: PMC9301881 DOI: 10.1016/j.nbd.2022.105610] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 11/21/2022] Open
Abstract
Aberrant glucocorticoid signaling via glucocorticoid receptors (GR) plays a critical role in alcohol use disorder (AUD). Acute alcohol withdrawal and protracted abstinence in dependent rats are associated with increased GR signaling and changes in GR-mediated transcriptional activity in the rat central nucleus of the amygdala (CeA). The GR antagonist mifepristone decreases alcohol consumption in dependent rats during acute withdrawal and protracted abstinence. Regulation of CeA synaptic activity by GR is currently unknown. Here, we utilized mifepristone and the selective GR antagonist CORT118335 (both at 10 μM) as pharmacological tools to dissect the role of GR on GABA transmission in male, adult Sprague-Dawley rats using slice electrophysiology. We subjected rats to chronic intermittent alcohol vapor exposure for 5–7 weeks to induce alcohol dependence. A subset of dependent rats subsequently underwent protracted alcohol withdrawal for 2 weeks, and air-exposed rats served as controls. Mifepristone reduced the frequency of pharmacologically-isolated spontaneous inhibitory postsynaptic currents (sIPSC) in the CeA (medial subdivision) without affecting postsynaptic measures in all groups, suggesting decreased GABA release with the largest effect in dependent rats. CORT118335 did not significantly alter GABA transmission in naive, but decreased sIPSC frequency in dependent rats. Similarly, mifepristone decreased amplitudes of evoked inhibitory postsynaptic potentials only in dependent rats and during protracted withdrawal. Collectively, our study provides insight into regulation of CeA GABAergic synapses by GR. Chronic ethanol enhances the efficiency of mifepristone and CORT118335, thus highlighting the potential of drugs targeting GR as a promising pharmacological avenue for the treatment of AUD.
Collapse
Affiliation(s)
- Sophia Khom
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America; Department of Pharmaceutical Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
| | - Larry Rodriguez
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America
| | - Pauravi Gandhi
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America
| | - Dean Kirson
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America; Department of Pharmacology, Addiction Science, and Toxicology, University of Tennessee Health Science Center, 71 S Manassas, Memphis, TN 38163, United States of America
| | - Michal Bajo
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America
| | - Christopher S Oleata
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America
| | - Leandro F Vendruscolo
- Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 251 Bayview Blvd., Baltimore, MD 21224, United States of America
| | - Barbara J Mason
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America
| | - Marisa Roberto
- Department of Molecular Medicine, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, United States of America.
| |
Collapse
|
2
|
Uta D, Hattori T, Yoshimura M. Analyses of the Mode of Action of an Alpha-Adrenoceptor Blocker in Substantia Gelatinosa Neurons in Rats. Int J Mol Sci 2021; 22:9636. [PMID: 34502543 PMCID: PMC8431806 DOI: 10.3390/ijms22179636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/24/2021] [Accepted: 09/03/2021] [Indexed: 11/17/2022] Open
Abstract
To elucidate why naftopidil increases the frequency of spontaneous synaptic currents in only some substantia gelatinosa (SG) neurons, post-hoc analyses were performed. Blind patch-clamp recording was performed using slice preparations of SG neurons from the spinal cords of adult rats. Spontaneous inhibitory and excitatory postsynaptic currents (sIPSCs and sEPSCs, respectively) were recorded. The ratios of the frequency and amplitude of the sIPSCs and sEPSCs following the introduction of naftopidil compared with baseline, and after the application of naftopidil, serotonin (5-HT), and prazosin, compared with noradrenaline (NA) were evaluated. First, the sIPSC analysis indicated that SG neurons reached their full response ratio for NA at 50 μM. Second, they responded to 5-HT (50 μM) with a response ratio similar to that for NA, but prazosin (10 μM) did not change the sEPSCs and sIPSCs. Third, the highest concentration of naftopidil (100 μM) led to two types of response in the SG neurons, which corresponded with the reactions to 5-HT and prazosin. These results indicate that not all neurons were necessarily activated by naftopidil, and that the micturition reflex may be regulated in a sophisticated manner by inhibitory mechanisms in these interneurons.
Collapse
Affiliation(s)
- Daisuke Uta
- Department of Applied Pharmacology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Tsuyoshi Hattori
- Department of Medical Affairs, Asahi Kasei Pharma Corporation, Tokyo 100-0006, Japan
| | - Megumu Yoshimura
- Department of Orthopedic Surgery, Nakamura Hospital, Fukuoka 822-0002, Japan;
| |
Collapse
|
3
|
Gawande DY, Shelkar GP, Liu J, Ayala AD, Pavuluri R, Choi D, Smith Y, Dravid SM. Glutamate Delta-1 Receptor Regulates Inhibitory Neurotransmission in the Nucleus Accumbens Core and Anxiety-Like Behaviors. Mol Neurobiol 2021; 58:4787-4801. [PMID: 34173171 DOI: 10.1007/s12035-021-02461-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 06/03/2021] [Indexed: 11/26/2022]
Abstract
Glutamate delta-1 receptor (GluD1) is a member of the ionotropic glutamate receptor family expressed at excitatory synapses and functions as a synaptogenic protein by interacting with presynaptic neurexin. We have previously shown that GluD1 plays a role in the maintenance of excitatory synapses in a region-specific manner. Loss of GluD1 leads to reduced excitatory neurotransmission in medium spiny neurons (MSNs) in the dorsal striatum, but not in the ventral striatum (both core and shell of the nucleus accumbens (NAc)). Here, we found that GluD1 loss leads to reduced inhibitory neurotransmission in MSNs of the NAc core as evidenced by a reduction in the miniature inhibitory postsynaptic current frequency and amplitude. Presynaptic effect of GluD1 loss was further supported by an increase in paired pulse ratio of evoked inhibitory responses indicating reduced release probability. Furthermore, analysis of GAD67 puncta indicated a reduction in the number of putative inhibitory terminals. The changes in mIPSC were independent of cannabinoid or dopamine signaling. A role of feed-forward inhibition was tested by selective ablation of GluD1 from PV neurons which produced modest reduction in mIPSCs. Behaviorally, local ablation of GluD1 from NAc led to hypolocomotion and affected anxiety- and depression-like behaviors. When GluD1 was ablated from the dorsal striatum, several behavioral phenotypes were altered in opposite manner compared to GluD1 ablation from NAc. Our findings demonstrate that GluD1 regulates inhibitory neurotransmission in the NAc by a combination of pre- and postsynaptic mechanisms which is critical for motor control and behaviors relevant to neuropsychiatric disorders.
Collapse
Affiliation(s)
- Dinesh Y Gawande
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Gajanan P Shelkar
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Jinxu Liu
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Anna D Ayala
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Ratnamala Pavuluri
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Diane Choi
- Yerkes National Primate Research Center, Atlanta, GA, 30329, USA
- UDALL Center of Excellence for Parkinson's Disease, Atlanta, GA, 30329, USA
| | - Yoland Smith
- Yerkes National Primate Research Center, Atlanta, GA, 30329, USA
- UDALL Center of Excellence for Parkinson's Disease, Atlanta, GA, 30329, USA
- Department of Neurology, Emory University, Atlanta, GA, 30329, USA
| | - Shashank M Dravid
- Department of Pharmacology and Neuroscience, Creighton University, 2500 California Plaza, Omaha, NE, USA.
| |
Collapse
|
4
|
Rouzer SK, Diaz MR. Factors of sex and age dictate the regulation of GABAergic activity by corticotropin-releasing factor receptor 1 in the medial sub-nucleus of the central amygdala. Neuropharmacology 2021; 189:108530. [PMID: 33741404 PMCID: PMC10538372 DOI: 10.1016/j.neuropharm.2021.108530] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 02/08/2023]
Abstract
Adolescents are phenotypically characterized with hyper-sensitivity to stress and inappropriate response to stress-inducing events. Despite behavioral distinctions from adults, investigations of developmental shifts in the function of stress peptide corticotropin-releasing factor (CRF) are generally limited. Rodent models have determined that CRF receptor 1 (CRFR1) activation within the central amygdala is associated with a stress response and induces increased GABAergic synaptic neurotransmission within adult males. To investigate age- and sex-specific function of this system, we performed whole-cell patch clamp electrophysiology in brain slices from naive adolescent (postnatal days (P) 40-49) and adult (>P70) male and female Sprague Dawley rats to assess GABAergic activity in the medial central amygdala (CeM). Our results indicate a dynamic influence of age and sex on neuronal excitability within this region, as well as basal spontaneous and miniature (m) inhibitory post-synaptic currents (IPSCs) in the CeM. In addition to replicating prior findings of CRFR1-regulated increases in mIPSC frequency in adult males, we found that the selective CRFR1 agonist, Stressin-1, attenuated mIPSC frequency in adolescent males, at a concentration that did not produce an effect in adult males. Importantly, this age-specific distinction was absent in females, as Stressin-1 attenuated mIPSC frequency in both adolescent and adult females. Finally, an increase in mIPSC frequency in response to the CRF1R antagonist, NBI 35965, was observed only in the CeM of adult males. Together, these data emphasize the robust influence of age and sex on neurophysiological function of a brain region involved in the production of the stress response.
Collapse
Affiliation(s)
- Siara Kate Rouzer
- Department of Psychology, Center for Development and Behavioral Neuroscience, Binghamton University, Binghamton, NY, 13902, United States; Developmental Exposure Alcohol Research Center, Binghamton University, Binghamton, NY, 13902, United States
| | - Marvin R Diaz
- Department of Psychology, Center for Development and Behavioral Neuroscience, Binghamton University, Binghamton, NY, 13902, United States; Developmental Exposure Alcohol Research Center, Binghamton University, Binghamton, NY, 13902, United States.
| |
Collapse
|
5
|
Liu PF, Wang Y, Zhang R, Xu L, Li JB, Mu D. Propofol modulates inhibitory inputs in paraventricular thalamic nucleus of mice. Neurosci Lett 2021; 756:135950. [PMID: 33979698 DOI: 10.1016/j.neulet.2021.135950] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/11/2021] [Accepted: 05/07/2021] [Indexed: 11/19/2022]
Abstract
The mechanisms of general anaesthetics such as propofol have drawn substantial attention. The effects of propofol on inhibitory postsynaptic currents are not exactly the same in different brain nuclei. Recent studies revealed that the paraventricular thalamic nucleus (PVT) is a critical nucleus modulating wakefulness. However, the effects of propofol on PVT neurons and the mechanisms underlying such effects remain unknown. Here, we performed the whole-cell recording of the PVT neurons in acute brain slices and bath application of propofol. We found that propofol hyperpolarized the membrane potentials of the PVT neurons and suppressed the action potentials induced by step-current injection. Propofol did not affect the spontaneous inhibitory postsynaptic currents (sIPSCs) amplitude or frequency, but prolonged the sIPSCs half-width. Besides, propofol increased miniature inhibitory synaptic currents (mIPSCs) frequency and half-width. Furthermore, propofol could induce GABAA receptors-mediated tonic inhibitory currents dose-dependently. Thus, our results demonstrate that propofol hyperpolarizes PVT neurons by modulating inhibitory currents via GABAA receptors in mice.
Collapse
Affiliation(s)
- Peng-Fei Liu
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yan Wang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Rui Zhang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ling Xu
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jin-Bao Li
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Di Mu
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
6
|
Rijal S, Jang SH, Park SJ, Han SK. Lithium Enhances the GABAergic Synaptic Activities on the Hypothalamic Preoptic Area (hPOA) Neurons. Int J Mol Sci 2021; 22:3908. [PMID: 33918982 PMCID: PMC8069239 DOI: 10.3390/ijms22083908] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022] Open
Abstract
Lithium (Li+) salt is widely used as a therapeutic agent for treating neurological and psychiatric disorders. Despite its therapeutic effects on neurological and psychiatric disorders, it can also disturb the neuroendocrine axis in patients under lithium therapy. The hypothalamic area contains GABAergic and glutamatergic neurons and their receptors, which regulate various hypothalamic functions such as the release of neurohormones, control circadian activities. At the neuronal level, several neurotransmitter systems are modulated by lithium exposure. However, the effect of Li+ on hypothalamic neuron excitability and the precise action mechanism involved in such an effect have not been fully understood yet. Therefore, Li+ action on hypothalamic neurons was investigated using a whole-cell patch-clamp technique. In hypothalamic neurons, Li+ increased the GABAergic synaptic activities via action potential independent presynaptic mechanisms. Next, concentration-dependent replacement of Na+ by Li+ in artificial cerebrospinal fluid increased frequencies of GABAergic miniature inhibitory postsynaptic currents without altering their amplitudes. Li+ perfusion induced inward currents in the majority of hypothalamic neurons independent of amino-acids receptor activation. These results suggests that Li+ treatment can directly affect the hypothalamic region of the brain and regulate the release of various neurohormones involved in synchronizing the neuroendocrine axis.
Collapse
Affiliation(s)
| | | | | | - Seong Kyu Han
- Department of Oral Physiology, School of Dentistry & Institute of Oral Bioscience, Jeonbuk National University, Jeonju 54896, Korea; (S.R.); (S.H.J.); (S.J.P.)
| |
Collapse
|
7
|
Zhang T, Yu F, Xu H, Chen M, Chen X, Guo L, Zhou C, Xu Y, Wang F, Yu J, Wu B. Dysregulation of REV-ERBα impairs GABAergic function and promotes epileptic seizures in preclinical models. Nat Commun 2021; 12:1216. [PMID: 33619249 PMCID: PMC7900242 DOI: 10.1038/s41467-021-21477-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 01/28/2021] [Indexed: 01/31/2023] Open
Abstract
To design potentially more effective therapies, we need to further understand the mechanisms underlying epilepsy. Here, we uncover the role of Rev-erbα in circadian regulation of epileptic seizures. We first show up-regulation of REV-ERBα/Rev-erbα in brain tissues from patients with epilepsy and a mouse model. Ablation or pharmacological modulation of Rev-erbα in mice decreases the susceptibility to acute and chronic seizures, and abolishes diurnal rhythmicity in seizure severity, whereas activation of Rev-erbα increases the animal susceptibility. Rev-erbα ablation or antagonism also leads to prolonged spontaneous inhibitory postsynaptic currents and elevated frequency in the mouse hippocampus, indicating enhanced GABAergic signaling. We also identify the transporters Slc6a1 and Slc6a11 as regulators of Rev-erbα-mediated clearance of GABA. Mechanistically, Rev-erbα promotes the expressions of Slc6a1 and Slc6a11 through transcriptional repression of E4bp4. Our findings propose Rev-erbα as a regulator of synaptic function at the crosstalk between pathways regulating the circadian clock and epilepsy.
Collapse
MESH Headings
- Acute Disease
- Animals
- Basic-Leucine Zipper Transcription Factors/genetics
- Basic-Leucine Zipper Transcription Factors/metabolism
- Chronic Disease
- Disease Models, Animal
- Epilepsy, Temporal Lobe/genetics
- Epilepsy, Temporal Lobe/pathology
- Epilepsy, Temporal Lobe/physiopathology
- GABA Plasma Membrane Transport Proteins/genetics
- GABA Plasma Membrane Transport Proteins/metabolism
- GABAergic Neurons/metabolism
- Gene Expression Regulation/drug effects
- Hippocampus/pathology
- Humans
- Inhibitory Postsynaptic Potentials/drug effects
- Isoquinolines/pharmacology
- Kindling, Neurologic/drug effects
- Mice, Inbred C57BL
- Mice, Knockout
- Nuclear Receptor Subfamily 1, Group D, Member 1/genetics
- Nuclear Receptor Subfamily 1, Group D, Member 1/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Seizures/genetics
- Seizures/pathology
- Seizures/physiopathology
- Small Molecule Libraries/pharmacology
- Thiophenes/pharmacology
- gamma-Aminobutyric Acid/metabolism
- Mice
Collapse
Affiliation(s)
- Tianpeng Zhang
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
- College of Pharmacy, Jinan University, Guangzhou, China
- Integrated Chinese and Western Medicine Postdoctoral research station, Jinan University, Guangzhou, China
| | - Fangjun Yu
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Haiman Xu
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Min Chen
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Xun Chen
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Lianxia Guo
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Cui Zhou
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Yuting Xu
- Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Fei Wang
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Jiandong Yu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China.
| | - Baojian Wu
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China.
- College of Pharmacy, Jinan University, Guangzhou, China.
| |
Collapse
|
8
|
Zhang M, Weiland H, Schöfbänker M, Zhang W. Estrogen Receptors Alpha and Beta Mediate Synaptic Transmission in the PFC and Hippocampus of Mice. Int J Mol Sci 2021; 22:ijms22031485. [PMID: 33540803 PMCID: PMC7867372 DOI: 10.3390/ijms22031485] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/17/2022] Open
Abstract
Distinct from ovarian estradiol, the steroid hormone 17ß-estradiol (E2) is produced in the brain and is involved in numerous functions, particularly acting as a neurosteroid. However, the physiological role of E2 and the mechanism of its effects are not well known. In hippocampal slices, 17ß-estradiol has been found to cause a modest increase in fast glutamatergic transmission; because some of these effects are rapid and acute, they might be mediated by membrane-associated receptors via nongenomic action. Moreover, activation of membrane estrogen receptors can rapidly modulate neuron function in a sex-specific manner. To further investigate the neurological role of E2, we examined the effect of E2, as an estrogen receptor (ER) agonist, on synaptic transmission in slices of the prefrontal cortex (PFC) and hippocampus in both male and female mice. Whole-cell recordings of spontaneous excitatory postsynaptic currents (sEPSC) in the PFC showed that E2 acts as a neuromodulator in glutamatergic transmission in the PFC in both sexes, but often in a cell-specific manner. The sEPSC amplitude and/or frequency responded to E2 in three ways, namely by significantly increasing, decreasing or having no response. Additional experiments using an agonist selective for ERß, diarylpropionitrile (DPN) showed that in males the sEPSC and spontaneous inhibitory postsynaptic currents sIPSC responses were similar to their E2 responses, but in females the estrogen receptor ß (ERß) agonist DPN did not influence excitatory transmission in the PFC. In contrast, in the hippocampus of both sexes E2 potentiated the gluatmatergic synaptic transmission in a subset of hippocampal cells. These data indicate that activation of E2 targeting probably a estrogen subtypes or different downstream signaling affect synaptic transmission in the brain PFC and hippocampus between males versus females mice.
Collapse
Affiliation(s)
- Mingyue Zhang
- Correspondence: ; Tel.: +49-2518-351-824; Fax: +49-2518-357-123
| | | | | | | |
Collapse
|
9
|
Wang N, Liu X, Li XT, Li XX, Ma W, Xu YM, Liu Y, Gao Q, Yang T, Wang H, Peng Y, Zhu XF, Guan YZ. 7,8-Dihydroxyflavone Alleviates Anxiety-Like Behavior Induced by Chronic Alcohol Exposure in Mice Involving Tropomyosin-Related Kinase B in the Amygdala. Mol Neurobiol 2021; 58:92-105. [PMID: 32895785 DOI: 10.1007/s12035-020-02111-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/01/2020] [Indexed: 01/08/2023]
Abstract
Alcohol use-associated disorders are highly comorbid with anxiety disorders; however, their mechanism remains unknown. The amygdala plays a central role in anxiety. We recently found that 7,8-dihydroxyflavone (7,8-DHF) significantly reduces withdrawal symptoms in a rat model of chronic intermittent alcohol (ethanol) exposure. This study aimed to determine the role of 7,8-DHF in regulating anxiety induced by chronic alcohol exposure and its associated underlying mechanism. Male C57BL/6J mice were exposed to chronic intermittent alcohol for 3 weeks followed by alcohol withdrawal for 12 h with or without 7,8-DHF administered intraperitoneally. All mice were tested using an open field test and elevated plus maze to assess anxiety-like behaviors. Synaptic activity and intrinsic excitability in basal and lateral amygdala (BLA) neurons were assessed using electrophysiological recordings. 7,8-DHF alleviated alcohol-induced anxiety-like behavior and attenuated alcohol-induced enhancement of activities in BLA pyramidal neurons. Furthermore, 7,8-DHF prevented alcohol withdrawal-evoked augmentation of glutamatergic transmission in the amygdala and had no effect on GABAergic transmission in the amygdala, as demonstrated by unaltered frequency and amplitude of spontaneous inhibitory postsynaptic currents. Microinjection of K252a, a tropomyosin-related kinase B (TrkB) antagonist, into the BLA blocked the effects of 7,8-DHF on anxiety-like behavior and neuronal activity in the BLA. Our findings suggest that 7,8-DHF alleviates alcohol-induced anxiety-like behavior induced by chronic alcohol exposure through regulation of glutamate transmission involving TrKB in the BLA.
Collapse
Affiliation(s)
- Na Wang
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Xing Liu
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Xin-Tong Li
- Department of Neurology, The Affiliated First Hospital of Jiamusi University, Jiamusi, 154000, China
| | - Xin-Xin Li
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Wei Ma
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Yan-Min Xu
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Yong Liu
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Qing Gao
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Tao Yang
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China
| | - Hongxuan Wang
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510828, China
| | - Ying Peng
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510828, China
| | - Xiao-Feng Zhu
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China.
| | - Yan-Zhong Guan
- Department of Physiology & Neurobiology, Mudanjiang Medical University, Mudanjiang, 157011, China.
| |
Collapse
|
10
|
Wan L, Chen L, Yu J, Wang G, Wu Z, Qian B, Liu X, Wang Y. Coordinated downregulation of KCC2 and GABA A receptor contributes to inhibitory dysfunction during seizure induction. Biochem Biophys Res Commun 2020; 532:489-495. [PMID: 32892950 DOI: 10.1016/j.bbrc.2020.08.082] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 08/22/2020] [Indexed: 01/25/2023]
Abstract
The GABAA receptor (GABAAR) is the main inhibitory receptor in the adult mammalian brain. GABAAR function is dependent on its expression, distribution, and the chloride (Cl-) transmembrane gradient, which is determined by the potassium-chloride cotransporter 2 (KCC2) in the adult brain. KCC2 and GABAAR are downregulated in an activity-dependent manner during seizure induction. Functionally, KCC2 and GABAAR are closely related membrane proteins which modulate GABAergic inhibition. However, it remains unclear how their downregulation during seizure induction is coordinated. This study aimed to assess this interaction. Our results revealed that KCC2 and GABAAR were simultaneously downregulated in both in vivo and in vitro seizure models induced by the convulsant cyclothazide (CTZ), which was at least partly due to structural coupling in hippocampal neuronal membranes. Immunohistochemistry revealed colocalization of gephyrin with KCC2 and co-immunoprecipitation exhibited a direct coupling between GABAAR α1-subunit and KCC2 protein in hippocampal cell membranes. KCC2 specific short hairpin RNA (KCC2-shRNA) was employed to specifically reduce the expression of KCC2 in cultured hippocampal neurons. This resulted in a significant reduction in KCC2-independent GABAergic miniature inhibitory post-synaptic current (mIPSC) amplitude in shKCC2-transfected neurons. Further, pre-treatment with furosemide, a KCC2 inhibitor, during CTZ stimulation followed by washout significantly prevented convulsant stimulation-induced membrane KCC2 downregulation and significantly attenuated GABAAR downregulation concomitant with recovery of suppressed KCC2-independent GABAergic mIPSC amplitude. Our results suggest that the coordinated downregulation of KCC2 and GABAAR during seizure induction exerts a strong functional impact on GABAAR, highlighting an important regulatory mechanism in epilepsy.
Collapse
Affiliation(s)
- Li Wan
- Rehabilitation Center, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, 518035, China.
| | - Lulan Chen
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Jiangning Yu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Guoxiang Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Zheng Wu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Binbin Qian
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Xu Liu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
| | - Yun Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institute of Biological Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
11
|
Li Q, Klein RC, Moore SD. Multiple sources of internal calcium stores mediate ethanol-induced presynaptic inhibitory GABA release in the central nucleus of the amygdala in mice. Psychopharmacology (Berl) 2020; 237:3303-3314. [PMID: 32705289 PMCID: PMC7644111 DOI: 10.1007/s00213-020-05613-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/17/2020] [Indexed: 11/27/2022]
Abstract
RATIONALE Ethanol can enhance GABA release in various brain regions via presynaptic mechanisms. However, the presynaptic action of ethanol on inhibitory GABA release is still not well understood. OBJECTIVES Since calcium is required for neurotransmitter release from presynaptic terminals, the purpose of this study was to investigate the role of both internal and external calcium signaling in ethanol-induced enhancement of GABA release within the central amygdala nucleus (CeA) in acute brain slice preparations. METHODS Whole-cell patch clamp electrophysiology was used to record miniature GABAA receptor-mediated inhibitory postsynaptic currents (mIPSCs) from CeA neurons. Ethanol-enhanced mIPSCs were recorded in the presence of antagonists that regulate internal and external calcium-mediated processes. RESULTS Bath-applied ethanol dose-dependently increased the mean frequency of mIPSCs without altering mIPSC amplitude. Ethanol-induced increases in mIPSC frequency were antagonized by dantrolene, 2-APB, and the endoplasmic reticulum calcium pump (SERCA) antagonists thapsigargin and cyclopiazonic acid (CPA). Blocking calcium release from mitochondria or via exocytosis with ruthenium red also attenuated mIPSCs while frequency was not altered in the presence of a non-selective calcium channel blocker cadmium. The L-type calcium blocker nifedipine, but not its analogue nimodipine, blocked ethanol-induced enhancement in CeA neurons. CONCLUSIONS These results demonstrate ethanol-induced presynaptic release of GABA is mediated by internal calcium stores and by disrupting neurotransmitter exocytosis within the CeA, a critical brain area involved in drugs of abuse and alcohol addiction.
Collapse
Affiliation(s)
- Qiang Li
- Addictions Division, Department of Psychiatry, Duke University Medical Center, Durham, NC, 27705, USA
- VISN 6 MIRECC, Durham VA Medical Center, Durham, NC, 27705, USA
| | - Rebecca C Klein
- Addictions Division, Department of Psychiatry, Duke University Medical Center, Durham, NC, 27705, USA
- VISN 6 MIRECC, Durham VA Medical Center, Durham, NC, 27705, USA
| | - Scott D Moore
- Addictions Division, Department of Psychiatry, Duke University Medical Center, Durham, NC, 27705, USA.
- VISN 6 MIRECC, Durham VA Medical Center, Durham, NC, 27705, USA.
| |
Collapse
|
12
|
Nakamura M, Jang IS, Yamaga T, Kotani N, Akaike N. Effects of nitrous oxide on glycinergic transmission in rat spinal neurons. Brain Res Bull 2020; 162:191-198. [PMID: 32599127 DOI: 10.1016/j.brainresbull.2020.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/16/2020] [Accepted: 06/22/2020] [Indexed: 11/19/2022]
Abstract
We investigated the effects of nitrous oxide (N2O) on glycinergic inhibitory whole-cell and synaptic responses using a "synapse bouton preparation," dissociated mechanically from rat spinal sacral dorsal commissural nucleus (SDCN) neurons. This technique can evaluate pure single- or multi-synaptic responses from native functional nerve endings and enable us to accurately quantify how N2O influences pre- and postsynaptic transmission. We found that 70 % N2O enhanced exogenous glycine-induced whole-cell currents (IGly) at glycine concentrations lower than 3 × 10-5 M, but did not affect IGly at glycine concentrations higher than 10-4 M. N2O did not affect the amplitude and 1/e decay-time of both spontaneous and miniature glycinergic inhibitory postsynaptic currents recorded in the absence and presence of tetrodotoxin (sIPSCs and mIPSCs, respectively). The decrease in frequency induced by N2O was observed in sIPSCs but not in mIPSCs, which was recorded in the presence of both tetrodotoxin and Cd2+, which block voltage-gated Na+ and Ca2+ channels, respectively. N2O also decreased the amplitude and increased the failure rate and paired-pulse ratio of action potential-evoked glycinergic inhibitory postsynaptic currents. N2O slightly decreased the Ba2+ currents mediated by voltage-gated Ca2+ channels in SDCN neurons. We found that N2O suppresses glycinergic responses at synaptic levels with presynaptic effect having much more predominant role. The difference between glycinergic whole-cell and synaptic responses suggests that extrasynaptic responses seriously modulate whole-cell currents. Our results strongly suggest that these responses may thus in part explain analgesic effects of N2O via marked glutamatergic inhibition by glycinergic responses in the spinal cord.
Collapse
Affiliation(s)
- Michiko Nakamura
- Department of Pharmacology, School of Dentistry, Kyungpook National University, 2177 Dalgubeol-daero, Jung-gu, Daegu, 700-412, Republic of Korea
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, 2177 Dalgubeol-daero, Jung-gu, Daegu, 700-412, Republic of Korea
| | - Toshitaka Yamaga
- Research Division for Life Science, Kumamoto Health Science University, 325 Izumi-machi, Kita-ku, Kumamoto 861-5598, Japan
| | - Naoki Kotani
- Research Division of Neurophysiology, Kitamoto Hospital, 3-7-6 Kawarasone, Koshigaya, Saitama 343-0821, Japan
| | - Norio Akaike
- Research Division of Neurophysiology, Kitamoto Hospital, 3-7-6 Kawarasone, Koshigaya, Saitama 343-0821, Japan; Research Division for Clinical Pharmacology, Medical Corporation, Juryo Group, Kumamoto Kinoh Hospital, 6-8-1 Yamamuro, Kita-ku, Kumamoto 860-8518, Japan.
| |
Collapse
|
13
|
Yu W, Wang L, Yang L, Li YJ, Wang M, Qiu C, Yang Q, Li XB, Huang YL, Liu R, Wu YM. Activation of LXRβ Signaling in the Amygdala Confers Anxiolytic Effects Through Rebalancing Excitatory and Inhibitory Neurotransmission upon Acute Stress. Neurotherapeutics 2020; 17:1253-1270. [PMID: 32297184 PMCID: PMC7609627 DOI: 10.1007/s13311-020-00857-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The balance of major excitatory (glutamate, Glu) and inhibitory (γ-aminobutyric acid, GABA), named as E/I neurotransmission, is critical for proper information processing. Anxiety-like responses upon stress are accompanied by abnormal alterations in the formation and function of synapses, resulting in the imbalance of E/I neurotransmission in the amygdala. Liver X receptors (LXRs), including LXRα and LXRβ isoforms, are nuclear receptors responsible for regulating central nervous system (CNS) functions besides maintaining metabolic homeostasis. However, little is known about the contribution of LXRs in E/I balance in regulating anxiety-related behaviors induced by stress. In this study, we found stress-induced anxiety led to the expression reduction of LXRβ not LXRα in mice amygdala. GW3965, a dual agonist for both LXRα and LXRβ, alleviated anxiety-like behaviors of stressed mice through activation of LXRβ, confirmed by the knockdown of LXRβ mediated by lentiviral shRNAs in the basolateral amygdala (BLA). This was paralleled by correcting the disequilibrium of E/I neurotransmission in the stressed BLA. Importantly, GW3965 exerted anxiolytic effects by correcting the promoted amplitude and frequency of miniature excitatory postsynaptic current (mEPSC), and augmenting the decreased that of miniature inhibitory postsynaptic current (mIPSC) in the stressed BLA. This suggests that stress-induced anxiety-like behaviors can largely be ascribed to the deficit of LXRβ signaling in E/I neurotransmission in BLA. These findings highlight the deficiency of LXRβ signaling in the amygdala linked to anxiety disorder, and LXRβ activation may represent a potential novel target for anxiety treatment with an alteration in synaptic transmission in the amygdala.
Collapse
Affiliation(s)
- Wen Yu
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China
| | - Lu Wang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China
| | - Le Yang
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi Province, People's Republic of China
| | - Yan-Jiao Li
- Department of Acupuncture and Moxibustion, Xi'an Hospital of Traditional Chinese Medicine, Xi'an, 710021, Shaanxi Province, People's Republic of China
| | - Min Wang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China
| | - Chen Qiu
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China
| | - Qi Yang
- Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi Province, People's Republic of China
| | - Xu-Bo Li
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China
| | - Yun-Long Huang
- Department of Pharmacology & Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Rui Liu
- Department of Rehabilitation Medicine, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China.
| | - Yu-Mei Wu
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, People's Republic of China.
| |
Collapse
|
14
|
Scaduto P, Sequeira A, Vawter MP, Bunney W, Limon A. Preservation of global synaptic excitatory to inhibitory ratio during long postmortem intervals. Sci Rep 2020; 10:8626. [PMID: 32451470 PMCID: PMC7248056 DOI: 10.1038/s41598-020-65377-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/04/2020] [Indexed: 12/01/2022] Open
Abstract
The study of postsynaptic excitation to inhibition (E/I ratio) imbalances in human brain diseases, is a highly relevant functional measurement poorly investigated due to postmortem degradation of synaptic receptors. We show that near-simultaneous recording of microtransplanted synaptic receptors after simulated morgue conditions allows the determination of the postsynaptic E/I ratio for at least 120 h after death, expanding the availability and use of human diseased tissue stored in brain banks.
Collapse
Affiliation(s)
- Pietro Scaduto
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases. School of Medicine. University of Texas Medical Branch at Galveston, Galveston, USA
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, Division of Human Physiology, University of Palermo, 90134, Palermo, Italy
| | - Adolfo Sequeira
- Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, CA, 92697, USA
| | - Marquis P Vawter
- Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, CA, 92697, USA
| | - William Bunney
- Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, CA, 92697, USA
| | - Agenor Limon
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases. School of Medicine. University of Texas Medical Branch at Galveston, Galveston, USA.
| |
Collapse
|
15
|
Delatour LC, Yeh PWL, Yeh HH. Prenatal Exposure to Ethanol Alters Synaptic Activity in Layer V/VI Pyramidal Neurons of the Somatosensory Cortex. Cereb Cortex 2020; 30:1735-1751. [PMID: 31647550 PMCID: PMC7132917 DOI: 10.1093/cercor/bhz199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 07/04/2019] [Accepted: 08/04/2019] [Indexed: 12/31/2022] Open
Abstract
Fetal alcohol spectrum disorder (FASD) encompasses a range of cognitive and behavioral deficits, with aberrances in the function of cerebral cortical pyramidal neurons implicated in its pathology. However, the mechanisms underlying these aberrances, including whether they persist well beyond ethanol exposure in utero, remain to be explored. We addressed these issues by employing a mouse model of FASD in which pregnant mice were exposed to binge-type ethanol from embryonic day 13.5 through 16.5. In both male and female offspring (postnatal day 28-32), whole-cell patch clamp recording of layer V/VI somatosensory cortex pyramidal neurons revealed increases in the frequency of excitatory and inhibitory postsynaptic currents. Furthermore, expressing channelrhodopsin in either GABAergic interneurons (Nkx2.1Cre-Ai32) or glutamatergic pyramidal neurons (Emx1IRES Cre-Ai32) revealed a shift in optically evoked paired-pulse ratio. These findings are consistent with an excitatory-inhibitory imbalance with prenatal ethanol exposure due to diminished inhibitory but enhanced excitatory synaptic strength. Prenatal ethanol exposure also altered the density and morphology of spines along the apical dendrites of pyramidal neurons. Thus, while both presynaptic and postsynaptic mechanisms are affected following prenatal exposure to ethanol, there is a prominent presynaptic component that contributes to altered inhibitory and excitatory synaptic transmission in the somatosensory cortex.
Collapse
Affiliation(s)
- Laurie C Delatour
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Pamela W L Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Hermes H Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| |
Collapse
|
16
|
Kenis-Coskun O, Giray E, Gunduz OH, Akyuz G. The effect of vitamin D replacement on spinal inhibitory pathways in women with chronic widespread pain. J Steroid Biochem Mol Biol 2020; 196:105488. [PMID: 31589918 DOI: 10.1016/j.jsbmb.2019.105488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 08/05/2019] [Accepted: 09/30/2019] [Indexed: 12/11/2022]
Abstract
Vitamin D replacement helps in pain reduction in patients with chronic widespread pain (CWP). But the current literature lack studies that investigate its mechanism. Cutaneous silent period (CSP) is the electrophysiologic analog of the spinal inhibitory pathways and an objective method to document their involvement. This study aims to show if vitamin D replacement has an effect on the spinal inhibitory pathways through CSP parameters. Female patients who have CWP with vitamin D deficiency were included. Patients received an 8-week replacement therapy of vitamin D. Patients' pain were evaluated using the visual analog scale (VAS) and Leeds assessment of neuropathic symptoms and signs pain scale (LANSS). Quality of life with Nottingham Health Profile (NHP) and CSP parameters were also recorded before and after treatment. A total of 51 patients were included in the final analyses. The mean age of the patients was 44.3 ± 12.7 (minimum 18-maximum 65). Mean symptom duration was 13.1 ± 6.7 (minimum3-maximum 24) months. Patients' mean BMI was 21.6 ± 3.9 (minimum 18.0 maximum 29.1). Patients' median VAS and LANSS scores decreased significantly (p < 0.01) and NHP scores improved significantly in all subsets (p < 0.01). Vitamin D replacement did not significantly change CSP latency and duration (p = 0.06 and p = 0.12).Vitamin D replacement does not seem to work via modifying the spinal inhibitory pathways that are involved in the formation of the cutaneous silent period. This is the first study to objectively investigate the effect of vitamin D replacement on central sensitization mechanisms.
Collapse
Affiliation(s)
- Ozge Kenis-Coskun
- Marmara University Medical Faculty Physical Medicine and Rehabilitation Department, Turkey.
| | - Esra Giray
- Marmara University Medical Faculty Physical Medicine and Rehabilitation Department, Turkey
| | - Osman Hakan Gunduz
- Marmara University Medical Faculty Physical Medicine and Rehabilitation Department, Turkey
| | - Gulseren Akyuz
- Marmara University Medical Faculty Physical Medicine and Rehabilitation Department, Turkey
| |
Collapse
|
17
|
Kang Y, Saito M, Toyoda H. Molecular and Regulatory Mechanisms of Desensitization and Resensitization of GABA A Receptors with a Special Reference to Propofol/Barbiturate. Int J Mol Sci 2020; 21:ijms21020563. [PMID: 31952324 PMCID: PMC7014398 DOI: 10.3390/ijms21020563] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/11/2020] [Accepted: 01/14/2020] [Indexed: 11/16/2022] Open
Abstract
It is known that desensitization of GABAA receptor (GABAAR)-mediated currents is paradoxically correlated with the slowdown of their deactivation, i.e., resensitization. It has been shown that an upregulation of calcineurin enhances the desensitization of GABAAR-mediated currents but paradoxically prolongs the decay phase of inhibitory postsynaptic currents/potentials without appreciable diminution of their amplitudes. The paradoxical correlation between desensitization and resensitization of GABAAR-mediated currents can be more clearly seen in response to a prolonged application of GABA to allow more desensitization, instead of brief pulse used in previous studies. Indeed, hump-like GABAAR currents were produced after a strong desensitization at the offset of a prolonged puff application of GABA in pyramidal cells of the barrel cortex, in which calcineurin activity was enhanced by deleting phospholipase C-related catalytically inactive proteins to enhance the desensitization/resensitization of GABAAR-mediated currents. Hump-like GABAAR currents were also evoked at the offset of propofol or barbiturate applications in hippocampal or sensory neurons, but not GABA applications. Propofol and barbiturate are useful to treat benzodiazepine/alcohol withdrawal syndrome, suggesting that regulatory mechanisms of desensitization/resensitization of GABAAR-mediated currents are important in understanding benzodiazepine/alcohol withdrawal syndrome. In this review, we will discuss the molecular and regulatory mechanisms underlying the desensitization and resensitization of GABAAR-mediated currents and their functional significances.
Collapse
Affiliation(s)
- Youngnam Kang
- Department of Behavioral Physiology, Graduate School of Human Sciences, Osaka University, Osaka 565-0871, Japan
- Department of Neurobiology and Physiology, School of Dentistry, Seoul National University, Seoul 110-749, Korea
- Correspondence: (Y.K.); (H.T.)
| | - Mitsuru Saito
- Department of Oral Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka 8-35-1, Kagoshima 890-8544, Japan;
| | - Hiroki Toyoda
- Department of Neuroscience and Oral Physiology, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
- Correspondence: (Y.K.); (H.T.)
| |
Collapse
|
18
|
Littlejohn EL, Espinoza L, Lopez MM, Smith BN, Boychuk CR. GABA A receptor currents in the dorsal motor nucleus of the vagus in females: influence of ovarian cycle and 5α-reductase inhibition. J Neurophysiol 2019; 122:2130-2141. [PMID: 31596653 PMCID: PMC6879959 DOI: 10.1152/jn.00039.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 09/23/2019] [Accepted: 10/07/2019] [Indexed: 11/22/2022] Open
Abstract
The dorsal motor nucleus of the vagus (DMV) contains the preganglionic motor neurons important in the regulation of glucose homeostasis and gastrointestinal function. Despite the role of sex in the regulation of these processes, few studies examine the role of sex and/or ovarian cycle in the regulation of synaptic neurotransmission to the DMV. Since GABAergic neurotransmission is critical to normal DMV function, the present study used in vitro whole cell patch-clamping to investigate whether sex differences exist in GABAergic neurotransmission to DMV neurons. It additionally investigated whether the ovarian cycle plays a role in those sex differences. The frequency of phasic GABAA receptor-mediated inhibitory postsynaptic currents in DMV neurons from females was lower compared with males, and this effect was TTX sensitive and abolished by ovariectomy (OVX). Amplitudes of GABAergic currents (both phasic and tonic) were not different. However, females demonstrated significantly more variability in the amplitude of both phasic and tonic GABAA receptor currents. This difference was eliminated by OVX in females, suggesting that these differences were related to reproductive hormone levels. This was confirmed for GABAergic tonic currents by comparing females in two ovarian stages, estrus versus diestrus. Female mice in diestrus had larger tonic current amplitudes compared with those in estrus, and this increase was abolished after administration of a 5α-reductase inhibitor but not modulation of estrogen. Taken together, these findings demonstrate that DMV neurons undergo GABAA receptor activity plasticity as a function of sex and/or sex steroids.NEW & NOTEWORTHY Results show that GABAergic signaling in dorsal vagal motor neurons (DMV) demonstrates sex differences and fluctuates across the ovarian cycle in females. These findings are the first to demonstrate that female GABAA receptor activity in this brain region is modulated by 5α-reductase-dependent hormones. Since DMV activity is critical to both glucose and gastrointestinal homeostasis, these results suggest that sex hormones, including those synthesized by 5α-reductase, contribute to visceral, autonomic function related to these physiological processes.
Collapse
Affiliation(s)
- Erica L Littlejohn
- Department of Cellular and Integrative Physiology, College of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Liliana Espinoza
- Department of Cellular and Integrative Physiology, College of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Monica M Lopez
- Department of Cellular and Integrative Physiology, College of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Bret N Smith
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
- Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Carie R Boychuk
- Department of Cellular and Integrative Physiology, College of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| |
Collapse
|
19
|
Davoudi M, Vijeepallam K, Azizi H, Mirnajafi-Zadeh J, Semnanian S. PKC inhibitor reversed the suppressive effect of orexin-A on IPSCs of locus coeruleus neurons in naloxone-induced morphine withdrawal. J Neural Transm (Vienna) 2019; 126:1425-1435. [PMID: 31493096 DOI: 10.1007/s00702-019-02064-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/09/2019] [Indexed: 11/26/2022]
Abstract
The locus coeruleus (LC) as a target of addictive drugs receives a dense projection of orexinergic fibres from the lateral hypothalamus (LH) and is accordingly a candidate site for the expression of the somatic aspects of morphine withdrawal. Recently it has been shown that the inhibitory synaptic currents of LC neurons decrease partly through orexin type 1 receptors in the context of naloxone-induced morphine withdrawal; however, its cellular mechanism remains unclear. In this study, whole-cell patch clamp recordings of LC neurons in brainstem slices were used to investigate the impact of protein kinase C (PKC) on GABAergic inhibitory post-synaptic currents (IPSCs) in the context of naloxone-induced morphine withdrawal. Male Wistar rats (P14-P21) received morphine (20 mg/kg, i.p.) daily for 7 consecutive days to induce morphine dependency. Our results showed that the application of PKC inhibitor (Go 6983; 1 µM) alone did not decrease the probability of GABA release in the LC neurons of the morphine-treated rats in the presence of naloxone. Although, Go 6983 reversed the reduction of the amplitude of evoked IPSCs (eIPSCs) and spontaneous IPSCs (sIPSCs) frequency induced by orexin-A but did not change the sIPSCs amplitude. These results indicate that the suppressive effect of orexin-A on IPSCs is probably reversed by PKC inhibitor in the LC neurons of morphine-treated rats in the context of naloxone withdrawal.
Collapse
Affiliation(s)
- Mahnaz Davoudi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Kamini Vijeepallam
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hossein Azizi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| |
Collapse
|
20
|
Askew CE, Lopez AJ, Wood MA, Metherate R. Nicotine excites VIP interneurons to disinhibit pyramidal neurons in auditory cortex. Synapse 2019; 73:e22116. [PMID: 31081950 PMCID: PMC6767604 DOI: 10.1002/syn.22116] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/02/2019] [Accepted: 05/09/2019] [Indexed: 12/13/2022]
Abstract
Nicotine activates nicotinic acetylcholine receptors and improves cognitive and sensory function, in part by its actions in cortical regions. Physiological studies show that nicotine amplifies stimulus-evoked responses in sensory cortex, potentially contributing to enhancement of sensory processing. However, the role of specific cell types and circuits in the nicotinic modulation of sensory cortex remains unclear. Here, we performed whole-cell recordings from pyramidal (Pyr) neurons and inhibitory interneurons expressing parvalbumin (PV), somatostatin (SOM), and vasoactive intestinal peptide (VIP) in mouse auditory cortex, in vitro. Bath application of nicotine strongly depolarized and excited VIP neurons, weakly depolarized Pyr neurons, and had no effect on the membrane potential of SOM or PV neurons. The use of receptor antagonists showed that nicotine's effects on VIP and Pyr neurons were direct and indirect, respectively. Nicotine also enhanced the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in Pyr, VIP, and SOM, but not PV, cells. Using Designer Receptors Exclusively Activated by Designer Drugs (DREADDs), we show that chemogenetic inhibition of VIP neurons prevents nicotine's effects on Pyr neurons. Since VIP cells preferentially contact other inhibitory interneurons, we suggest that nicotine drives VIP cell firing to disinhibit Pyr cell somata, potentially making Pyr cells more responsive to auditory stimuli. In parallel, activation of VIP cells also directly inhibits Pyr neurons, likely altering integration of other synaptic inputs. These cellular and synaptic mechanisms likely contribute to nicotine's beneficial effects on cognitive and sensory function.
Collapse
Affiliation(s)
- Caitlin E. Askew
- Department of Neurobiology and Behavior, Center for Hearing ResearchUniversity of California, IrvineIrvineCalifornia
| | - Alberto J. Lopez
- Department of Neurobiology and Behavior, Center for Hearing ResearchUniversity of California, IrvineIrvineCalifornia
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, Center for Hearing ResearchUniversity of California, IrvineIrvineCalifornia
| | - Raju Metherate
- Department of Neurobiology and Behavior, Center for Hearing ResearchUniversity of California, IrvineIrvineCalifornia
| |
Collapse
|
21
|
Xu Y, Shen FY, Liu YZ, Wang L, Wang YW, Wang Z. Dependence of Generation of Hippocampal CA1 Slow Oscillations on Electrical Synapses. Neurosci Bull 2019; 36:39-48. [PMID: 31468346 DOI: 10.1007/s12264-019-00419-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 05/26/2019] [Indexed: 01/01/2023] Open
Abstract
Neuronal oscillations in the hippocampus are critical for many brain functions including learning and memory. The underlying mechanism of oscillation generation has been extensively investigated in terms of chemical synapses and ion channels. Recently, electrical synapses have also been indicated to play important roles, as reported in various brain areas in vivo and in brain slices. However, this issue remains to be further clarified, including in hippocampal networks. Here, using the completely isolated hippocampus, we investigated in vitro the effect of electrical synapses on slow CA1 oscillations (0.5 Hz-1.5 Hz) generated intrinsically by the hippocampus. We found that these oscillations were totally abolished by bath application of a general blocker of gap junctions (carbenoxolone) or a specific blocker of electrical synapses (mefloquine), as determined by whole-cell recordings in both CA1 pyramidal cells and fast-spiking cells. Our findings indicate that electrical synapses are required for the hippocampal generation of slow CA1 oscillations.
Collapse
Affiliation(s)
- Yuan Xu
- Institute and Key Laboratory of Brain Functional Genomics of The Chinese Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Feng-Yan Shen
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Yu-Zhang Liu
- Institute and Key Laboratory of Brain Functional Genomics of The Chinese Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Lidan Wang
- Institute and Key Laboratory of Brain Functional Genomics of The Chinese Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Ying-Wei Wang
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Zhiru Wang
- Institute and Key Laboratory of Brain Functional Genomics of The Chinese Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China.
| |
Collapse
|
22
|
Löfgren M, Holmberg E, Bäckström T, Egecioglu E, Dickson SL. The additive effect of allopregnanolone on ghrelin's orexigenic effect in rats. Neuropeptides 2019; 76:101937. [PMID: 31253440 DOI: 10.1016/j.npep.2019.101937] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 06/08/2019] [Accepted: 06/12/2019] [Indexed: 11/20/2022]
Abstract
The progesterone metabolite, allopregnanolone (AlloP), is a GABAA receptor modulating steroid and is known to have orexigenic and pro-obesity effects. The neurobiological mechanisms underpinning these effects are most likely due to enhanced GABAergic signaling in the lateral arcuate nucleus (ARC) and medial paraventricular nucleus (PVN) of the hypothalamus. Inspired by the finding that GABAergic signaling is also important for the orexigenic effects of the circulating hormone, ghrelin, we sought to determine the extent to which AlloP (one of the most potent endogenous GABAA-receptor modulators) operates alongside ghrelin to enhance food intake. Male rats with ad libitum access to standard chow were injected intravenously with AlloP and/or ghrelin, alone or in combination. The intake of the standard chow was greater after AlloP 1 mg/kg together with ghrelin 30 μg/kg than with 30 μg/kg ghrelin alone. Food intake was also increased for the combined treatment of AlloP 0.5 mg/kg + ghrelin 10 μg/kg, AlloP 1 mg/kg + ghrelin 10 μg/kg, and AlloP 0.5 mg/kg + ghrelin 30 μg/kg. There was no significant difference in food intake between the two ghrelin doses or between the two doses of AlloP and the vehicle. In electrophysiological studies, physiologically relevant concentrations of AlloP prolonged the current decay time of spontaneous inhibitory post-synaptic current of dissociated cells of the ARC and PVN. We conclude that AlloP enhances the hyperphagic effect of ghrelin, findings of potential relevance for the hyperphagia associated with the luteal phase of the reproductive cycle.
Collapse
Affiliation(s)
- Magnus Löfgren
- Department of Clinical Sciences, Obstetrics and Gynaecology, Umeå University Hospital, SE-Building QA, 3rd floor, 901 85 Umeå, Sweden.
| | - Ellinor Holmberg
- Department of Clinical Sciences, Obstetrics and Gynaecology, Umeå University Hospital, SE-Building QA, 3rd floor, 901 85 Umeå, Sweden
| | - Torbjörn Bäckström
- Department of Clinical Sciences, Obstetrics and Gynaecology, Umeå University Hospital, SE-Building QA, 3rd floor, 901 85 Umeå, Sweden
| | - Emil Egecioglu
- Department of Experimental Medical Science, Appetite Regulation Unit, Faculty of Medicine, Lund University, 221 84 Lund, Sweden
| | - Suzanne L Dickson
- Institute for Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, P.O. Box 434, SE-405 30 Gothenburg, Sweden
| |
Collapse
|
23
|
Sonar VP, Fois B, Distinto S, Maccioni E, Meleddu R, Cottiglia F, Acquas E, Kasture S, Floris C, Colombo D, Sissi C, Sanna E, Talani G. Ferulic Acid Esters and Withanolides: In Search of Withania somnifera GABA A Receptor Modulators. J Nat Prod 2019; 82:1250-1257. [PMID: 30998355 DOI: 10.1021/acs.jnatprod.8b01023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nine compounds, including two undescribed withanolides, withasomniferolides A and B (1 and 2), three known withanolides (3-5), a ferulic acid dimeric ester (6), and an inseparable mixture of three long alkyl chain ferulic acid esters (7-9), were isolated from a GABAA receptor positive activator methanol extract of the roots of Withania somnifera. The structures of the isolated compounds were elucidated based on NMR, MS, and ECD data analysis. In order to bioassay the single ferulic acid derivatives, compounds 6-9 were also synthesized. The most active compound, docosanyl ferulate (9), was able to enhance the GABAA receptor inhibitory postsynaptic currents with an IC50 value of 7.9 μM. These results, by showing an ability to modulate the GABAA receptor function, cast fresh light on the biological activities of the secondary metabolites of W. somnifera roots.
Collapse
Affiliation(s)
- Vijay P Sonar
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
- R. C. Patel Institute of Pharmaceutical Education and Research , Shirpur , 425404 India
| | - Benedetta Fois
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Simona Distinto
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Elias Maccioni
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Rita Meleddu
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Filippo Cottiglia
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Elio Acquas
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
- Centre of Excellence on Neurobiology of Addiction , University of Cagliari , 09042 Cagliari , Italy
| | - Sanjay Kasture
- Department of Pharmacology , Sanjivani College of Pharmaceutical Education & Research , Kopargaon , 423603 India
| | - Costantino Floris
- Department of Chemical and Geological Sciences , University of Cagliari , 09042 Monserrato , Italy
| | - Daniele Colombo
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences , University of Padova , 35131 Padova , Italy
| | - Enrico Sanna
- Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy
- Centre of Excellence on Neurobiology of Addiction , University of Cagliari , 09042 Cagliari , Italy
| | - Giuseppe Talani
- National Research Council (CNR) , Institute of Neuroscience , 09042 Monserrato , Italy
| |
Collapse
|
24
|
Pickford J, Apps R, Bashir ZI. Muscarinic Receptor Modulation of the Cerebellar Interpositus Nucleus In Vitro. Neurochem Res 2019; 44:627-635. [PMID: 30117095 PMCID: PMC6420442 DOI: 10.1007/s11064-018-2613-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 08/09/2018] [Accepted: 08/11/2018] [Indexed: 11/25/2022]
Abstract
How the cerebellum carries out its functions is not clear, even for its established roles in motor control. In particular, little is known about how the cerebellar nuclei (CN) integrate their synaptic and neuromodulatory inputs to generate cerebellar output. CN neurons receive inhibitory inputs from Purkinje cells, excitatory inputs from mossy fibre and climbing fibre collaterals, as well as a variety of neuromodulatory inputs, including cholinergic inputs. In this study we tested how activation of acetylcholine receptors modulated firing rate, intrinsic properties and synaptic transmission in the CN. Using in vitro whole-cell patch clamp recordings from neurons in the interpositus nucleus, the acetylcholine receptor agonist carbachol was shown to induce a short-term increase in firing rate, increase holding current and decrease input resistance of interpositus CN neurons. Carbachol also induced long-term depression of evoked inhibitory postsynaptic currents and a short-term depression of evoked excitatory postsynaptic currents. All effects were shown to be dependent upon muscarinic acetylcholine receptor activation. Overall, the present study has identified muscarinic receptor activation as a modulator of CN activity.
Collapse
Affiliation(s)
- J Pickford
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK.
| | - R Apps
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK
| | - Z I Bashir
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK
| |
Collapse
|
25
|
Murayama S, Yamamoto K, Fujita S, Takei H, Inui T, Ogiso B, Kobayashi M. Extracellular glucose-dependent IPSC enhancement by leptin in fast-spiking to pyramidal neuron connections via JAK2-PI3K pathway in the rat insular cortex. Neuropharmacology 2019; 149:133-148. [PMID: 30772375 DOI: 10.1016/j.neuropharm.2019.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/07/2019] [Accepted: 02/13/2019] [Indexed: 01/29/2023]
Abstract
Leptin is produced in the adipocytes and plays a pivotal role in regulation of energy balance by controlling appetite and metabolism. Leptin receptors are widely distributed in the brain, especially in the hypothalamus, hippocampus, and neocortex. The insular cortex (IC) processes gustatory and visceral information, which functionally correlate to feeding behavior. However, it is still an open issue whether and how leptin modulates IC neural activities. Our paired whole-cell patch-clamp recordings using IC slice preparations demonstrated that unitary inhibitory postsynaptic currents (uIPSCs) but not uEPSCs were potentiated by leptin in the connections between pyramidal (PNs) and fast-spiking neurons (FSNs). The leptin-induced increase in uIPSC amplitude was accompanied by a decrease in paired-pulse ratio. Under application of inhibitors of JAK2-PI3K but not MAPK pathway, leptin did not change uIPSC amplitude. Variance-mean analysis revealed that leptin increased the release probability but not the quantal size and the number of release site. These electrophysiological findings suggest that the leptin-induced uIPSC increase is mediated by activation of JAK2-PI3K pathway in presynaptic FSNs. An in vivo optical imaging revealed that leptin application decreased excitatory propagation in IC induced by electrical stimulation of IC. These leptin-induced effects were not observed under the low energy states: low glucose concentration (2.5 mM) in vitro and one-day-fasting condition in vivo. However, leptin enhanced uIPSCs under application of low glucose with an AMPK inhibitor. These results suggest that leptin suppresses IC excitation by facilitating GABA release in FSN→PN connections, which may not occur under a hunger state.
Collapse
Affiliation(s)
- Shota Murayama
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Department of Endodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Kiyofumi Yamamoto
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Satoshi Fujita
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Hiroki Takei
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Department of Pedodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Tadashi Inui
- Department of Psychology and Program in Neuroscience, Florida State University, Tallahassee, FL, USA
| | - Bunnai Ogiso
- Department of Endodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Masayuki Kobayashi
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Molecular Dynamics Imaging Unit, RIKEN Centre for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan.
| |
Collapse
|
26
|
Atif M, Smith JJ, Estrada-Mondragon A, Xiao X, Salim AA, Capon RJ, Lynch JW, Keramidas A. GluClR-mediated inhibitory postsynaptic currents reveal targets for ivermectin and potential mechanisms of ivermectin resistance. PLoS Pathog 2019; 15:e1007570. [PMID: 30695069 PMCID: PMC6368337 DOI: 10.1371/journal.ppat.1007570] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/08/2019] [Accepted: 01/08/2019] [Indexed: 12/19/2022] Open
Abstract
Glutamate-gated chloride channel receptors (GluClRs) mediate inhibitory neurotransmission at invertebrate synapses and are primary targets of parasites that impact drastically on agriculture and human health. Ivermectin (IVM) is a broad-spectrum pesticide that binds and potentiates GluClR activity. Resistance to IVM is a major economic and health concern, but the molecular and synaptic mechanisms of resistance are ill-defined. Here we focus on GluClRs of the agricultural endoparasite, Haemonchus contortus. We demonstrate that IVM potentiates inhibitory input by inducing a tonic current that plateaus over 15 minutes and by enhancing post-synaptic current peak amplitude and decay times. We further demonstrate that IVM greatly enhances the active durations of single receptors. These effects are greatly attenuated when endogenous IVM-insensitive subunits are incorporated into GluClRs, suggesting a mechanism of IVM resistance that does not affect glutamate sensitivity. We discovered functional groups of IVM that contribute to tuning its potency at different isoforms and show that the dominant mode of access of IVM is via the cell membrane to the receptor. Glutamate-gated chloride channel receptors (GluClRs) mediate chemoelectric inhibition in invertebrate animals and are targets for broad-spectrum pesticides such as ivermectin. However, resistance to ivermectin threatens the effective control of invertebrates that cause a range of agricultural and human diseases. This study investigates different isoforms of GluClR expressed by the major agricultural endoparasite, Haemonchus contortus, on a synaptic and single receptor level. We discovered that ivermectin enhances synaptic current amplitude and decay and lengthens single receptor activity. Furthermore, ivermectin is less efficacious at GluClRs that incorporate a naturally ivermectin-resistant subunit, suggesting a potential resistance mechanism. Finally, we identify two chemical interactions between the GluClR and ivermectin that determine its potency and show that ivermectin binds to GluClRs via cell membrane interactions.
Collapse
Affiliation(s)
- Mohammed Atif
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | - Jennifer J. Smith
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | | | - Xue Xiao
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Angela A. Salim
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Robert J. Capon
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Joseph W. Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
- * E-mail: (AK); (JWL)
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
- * E-mail: (AK); (JWL)
| |
Collapse
|
27
|
Patel RR, Khom S, Steinman MQ, Varodayan FP, Kiosses WB, Hedges DM, Vlkolinsky R, Nadav T, Polis I, Bajo M, Roberts AJ, Roberto M. IL-1β expression is increased and regulates GABA transmission following chronic ethanol in mouse central amygdala. Brain Behav Immun 2019; 75:208-219. [PMID: 30791967 PMCID: PMC6383367 DOI: 10.1016/j.bbi.2018.10.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/09/2018] [Accepted: 10/25/2018] [Indexed: 12/20/2022] Open
Abstract
The interleukin-1 system (IL-1) is a prominent pro-inflammatory pathway responsible for the initiation and regulation of immune responses. Human genetic and preclinical studies suggest a critical role for IL-1β signaling in ethanol drinking and dependence, but little is known about the effects of chronic ethanol on the IL-1 system in addiction-related brain regions such as the central amygdala (CeA). In this study, we generated naïve, non-dependent (Non-Dep) and dependent (Dep) male mice using a paradigm of chronic-intermittent ethanol vapor exposure interspersed with two-bottle choice to examine 1) the expression of IL-1β, 2) the role of the IL-1 system on GABAergic transmission, and 3) the potential interaction with the acute effects of ethanol in the CeA. Immunohistochemistry with confocal microscopy was used to assess expression of IL-1β in microglia and neurons in the CeA, and whole-cell patch clamp recordings were obtained from CeA neurons to measure the effects of IL-1β (50 ng/ml) or the endogenous IL-1 receptor antagonist (IL-1ra; 100 ng/ml) on action potential-dependent spontaneous inhibitory postsynaptic currents (sIPSCs). Overall, we found that IL-1β expression is significantly increased in microglia and neurons of Dep compared to Non-Dep and naïve mice, IL-1β and IL-1ra bi-directionally modulate GABA transmission through both pre- and postsynaptic mechanisms in all three groups, and IL-1β and IL-1ra do not alter the facilitation of GABA release induced by acute ethanol. These data suggest that while ethanol dependence induces a neuroimmune response in the CeA, as indicated by increased IL-1β expression, this does not significantly alter the neuromodulatory role of IL-1β on synaptic transmission.
Collapse
Affiliation(s)
- Reesha R Patel
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Sophia Khom
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Michael Q Steinman
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Florence P Varodayan
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - William B Kiosses
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - David M Hedges
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Roman Vlkolinsky
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Tali Nadav
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Ilham Polis
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Michal Bajo
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Amanda J Roberts
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Marisa Roberto
- The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA.
| |
Collapse
|
28
|
Abstract
Recent studies have shown that ethanol produces a widespread modulation
of neuronal activity in the central nervous system. It is not fully
understood, however, how ethanol changes nociceptive transmission. We
investigated acute effects of ethanol on synaptic transmission in the
substantia gelatinosa (lamina II of the spinal dorsal horn) and
mechanical responses in the spinal dorsal horn. In substantia
gelatinosa neurons, bath application of ethanol at low concentration
(10 mM) did not change the frequency and amplitude of spontaneous
inhibitory postsynaptic currents. At medium to high concentrations
(20–100 mM), however, ethanol elicited a barrage of large amplitude
spontaneous inhibitory postsynaptic currents. In the presence of
tetrodotoxin, such enhancement of spontaneous inhibitory postsynaptic
currents was not detected. In addition, ethanol (20–100 mM) increased
the frequency of spontaneous discharge of vesicular GABA
transporter-Venus-labeled neurons and suppressed the mechanical
nociceptive response in wide-dynamic range neurons in the spinal
dorsal horn. The present results suggest that ethanol may reduce
nociceptive information transfer in the spinal dorsal horn by
enhancement of inhibitory GABAergic and glycinergic synaptic
transmission.
Collapse
Affiliation(s)
- Akihiro Yamada
- Department of Neurophysiology, Hyogo College of
Medicine, Nishinomiya, Japan
- Department of Neuropharmacology, Graduate School of
Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
- Department of Information Physiology, National
Institute for Physiological Sciences, Okazaki, Japan
| | - Kohei Koga
- Department of Neurophysiology, Hyogo College of
Medicine, Nishinomiya, Japan
| | - Kazuhiko Kume
- Department of Neuropharmacology, Graduate School of
Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Masahiro Ohsawa
- Department of Neuropharmacology, Graduate School of
Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Hidemasa Furue
- Department of Neurophysiology, Hyogo College of
Medicine, Nishinomiya, Japan
- Department of Information Physiology, National
Institute for Physiological Sciences, Okazaki, Japan
- School of Life Science, Graduate University for
Advanced Studies, Okazaki, Japan
- Hidemasa Furue, Department of
Neurophysiology 663–8131, Hyogo College of Medicine, Nishinomiya,
Japan.
| |
Collapse
|
29
|
Shi Y, Chen Y, Wang Y. Kir2.1 Channel Regulation of Glycinergic Transmission Selectively Contributes to Dynamic Mechanical Allodynia in a Mouse Model of Spared Nerve Injury. Neurosci Bull 2018; 35:301-314. [PMID: 30203408 DOI: 10.1007/s12264-018-0285-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 07/20/2018] [Indexed: 11/25/2022] Open
Abstract
Neuropathic pain is a chronic debilitating symptom characterized by spontaneous pain and mechanical allodynia. It occurs in distinct forms, including brush-evoked dynamic and filament-evoked punctate mechanical allodynia. Potassium channel 2.1 (Kir2.1), which exhibits strong inward rectification, is and regulates the activity of lamina I projection neurons. However, the relationship between Kir2.1 channels and mechanical allodynia is still unclear. In this study, we first found that pretreatment with ML133, a selective Kir2.1 inhibitor, by intrathecal administration, preferentially inhibited dynamic, but not punctate, allodynia in mice with spared nerve injury (SNI). Intrathecal injection of low doses of strychnine, a glycine receptor inhibitor, selectively induced dynamic, but not punctate allodynia, not only in naïve but also in ML133-pretreated mice. In contrast, bicuculline, a GABAA receptor antagonist, induced only punctate, but not dynamic, allodynia. These results indicated the involvement of glycinergic transmission in the development of dynamic allodynia. We further found that SNI significantly suppressed the frequency, but not the amplitude, of the glycinergic spontaneous inhibitory postsynaptic currents (gly-sIPSCs) in neurons on the lamina II-III border of the spinal dorsal horn, and pretreatment with ML133 prevented the SNI-induced gly-sIPSC reduction. Furthermore, 5 days after SNI, ML133, either by intrathecal administration or acute bath perfusion, and strychnine sensitively reversed the SNI-induced dynamic, but not punctate, allodynia and the gly-sIPSC reduction in lamina IIi neurons, respectively. In conclusion, our results suggest that blockade of Kir2.1 channels in the spinal dorsal horn selectively inhibits dynamic, but not punctate, mechanical allodynia by enhancing glycinergic inhibitory transmission.
Collapse
Affiliation(s)
- Yiqian Shi
- Department of Neurology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China
| | - Yangyang Chen
- Department of Neurology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China
| | - Yun Wang
- Department of Neurology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
30
|
Domoto M, Sasase H, Wada S, Ito S, Deyama S, Hinoi E, Kaneko S, Kaneda K. The synthetic cannabinoid 5F-AMB changes the balance between excitation and inhibition of layer V pyramidal neurons in the mouse medial prefrontal cortex. Psychopharmacology (Berl) 2018; 235:2367-2376. [PMID: 29858613 DOI: 10.1007/s00213-018-4933-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 05/24/2018] [Indexed: 11/30/2022]
Abstract
RATIONALE 5F-AMB is one of the synthetic cannabinoids (SCs) designed to potentiate the ability to activate cannabinoid 1 (CB1) receptors and is abused worldwide. Although inhalation of 5F-AMB elicits serious adverse effects including impaired memory and consciousness, it is not known whether and how 5F-AMB affects the activity of pyramidal neurons in the medial prefrontal cortex (mPFC), a brain region associated with higher functions such as memory and cognition. OBJECTIVES In the present study, we examined the effects of 5F-AMB on mPFC layer V (L5) pyramidal neurons using in vitro whole-cell patch-clamp recordings. RESULTS Bath application of 5F-AMB attenuated the frequency but not the amplitude of spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs). The attenuating effects of 5F-AMB were abolished by the CB1 receptor antagonist AM251. 5F-AMB also attenuated the frequency of miniature EPSCs and IPSCs recorded in the presence of tetrodotoxin. Moreover, the extent of attenuating effects of 5F-AMB on stimulus-evoked EPSCs was significantly larger than that on evoked IPSCs. CONCLUSIONS These findings suggest that 5F-AMB attenuates both excitatory and inhibitory transmission in mPFC L5 pyramidal neurons via the activation of CB1 receptors located in presynaptic terminals. Further, the net impact of 5F-AMB on L5 pyramidal neurons is inhibition due to the change in balance between excitation and inhibition. This inhibitory effect might at least partly contribute to the expression of the adverse effects induced by 5F-AMB inhalation.
Collapse
Affiliation(s)
- Masaki Domoto
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Hitoki Sasase
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Shintaro Wada
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Shiho Ito
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Satoshi Deyama
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Eiichi Hinoi
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Shuji Kaneko
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Katsuyuki Kaneda
- Laboratory of Molecular Pharmacology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
| |
Collapse
|
31
|
Rhee J, Park K, Kim KC, Shin CY, Chung C. Impaired Hippocampal Synaptic Plasticity and Enhanced Excitatory Transmission in a Novel Animal Model of Autism Spectrum Disorders with Telomerase Reverse Transcriptase Overexpression. Mol Cells 2018; 41:486-494. [PMID: 29696935 PMCID: PMC5974625 DOI: 10.14348/molcells.2018.0145] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 04/02/2018] [Indexed: 01/23/2023] Open
Abstract
Recently, we have reported that animals with telomerase reverse transcriptase (TERT) overexpression exhibit reduced social interaction, decreased preference for novel social interaction and poor nest-building behaviors symptoms that mirror those observed in human autism spectrum disorders (ASD). Overexpression of TERT also alters the excitatory/inhibitory (E/I) ratio in the medial prefrontal cortex. However, the effects of TERT overexpression on hippocampal-dependent learning and synaptic efficacy have not been investigated. In the present study, we employed electrophysiological approaches in combination with behavioral analysis to examine hippocampal function of TERT transgenic (TERT-tg) mice and FVB controls. We found that TERT overexpression results in enhanced hippocampal excitation with no changes in inhibition and significantly impairs long-term synaptic plasticity. Interestingly, the expression levels of phosphorylated CREB and phosphory-lated CaMKIIα were significantly decreased while the expression level of CaMKIIα was slightly increased in the hippocampus of TERT-overexpressing mice. Our observations highlight the importance of TERT in normal synaptic function and behavior and provide additional information on a novel animal model of ASD associated with TERT overexpression.
Collapse
Affiliation(s)
- Jeehae Rhee
- Department of Biological Sciences, College of Bioscience and Biotechnology, Konkuk University, Seoul 05029,
Korea
| | - Kwanghoon Park
- Department of Biological Sciences, College of Bioscience and Biotechnology, Konkuk University, Seoul 05029,
Korea
| | - Ki Chan Kim
- Department of Neuroscience and Department of Advanced Translational Medicine, School of Medicine, Konkuk University, Seoul 05029,
Korea
| | - Chan Young Shin
- Department of Neuroscience and Department of Advanced Translational Medicine, School of Medicine, Konkuk University, Seoul 05029,
Korea
| | - ChiHye Chung
- Department of Biological Sciences, College of Bioscience and Biotechnology, Konkuk University, Seoul 05029,
Korea
| |
Collapse
|
32
|
Vascak M, Jin X, Jacobs KM, Povlishock JT. Mild Traumatic Brain Injury Induces Structural and Functional Disconnection of Local Neocortical Inhibitory Networks via Parvalbumin Interneuron Diffuse Axonal Injury. Cereb Cortex 2018; 28:1625-1644. [PMID: 28334184 PMCID: PMC5907353 DOI: 10.1093/cercor/bhx058] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 01/20/2017] [Indexed: 12/18/2022] Open
Abstract
Diffuse axonal injury (DAI) plays a major role in cortical network dysfunction posited to cause excitatory/inhibitory imbalance after mild traumatic brain injury (mTBI). Current thought holds that white matter (WM) is uniquely vulnerable to DAI. However, clinically diagnosed mTBI is not always associated with WM DAI. This suggests an undetected neocortical pathophysiology, implicating GABAergic interneurons. To evaluate this possibility, we used mild central fluid percussion injury to generate DAI in mice with Cre-driven tdTomato labeling of parvalbumin (PV) interneurons. We followed tdTomato+ profiles using confocal and electron microscopy, together with patch-clamp analysis to probe for DAI-mediated neocortical GABAergic interneuron disruption. Within 3 h post-mTBI tdTomato+ perisomatic axonal injury (PSAI) was found across somatosensory layers 2-6. The DAI marker amyloid precursor protein colocalized with GAD67 immunoreactivity within tdTomato+ PSAI, representing the majority of GABAergic interneuron DAI. At 24 h post-mTBI, we used phospho-c-Jun, a surrogate DAI marker, for retrograde assessments of sustaining somas. Via this approach, we estimated DAI occurs in ~9% of total tdTomato+ interneurons, representing ~14% of pan-neuronal DAI. Patch-clamp recordings of tdTomato+ interneurons revealed decreased inhibitory transmission. Overall, these data show that PV interneuron DAI is a consistent and significant feature of experimental mTBI with important implications for cortical network dysfunction.
Collapse
Affiliation(s)
- Michal Vascak
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, PO Box 980709, Richmond, VA 23298-0709, USA
| | - Xiaotao Jin
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, PO Box 980709, Richmond, VA 23298-0709, USA
| | - Kimberle M Jacobs
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, PO Box 980709, Richmond, VA 23298-0709, USA
| | - John T Povlishock
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, PO Box 980709, Richmond, VA 23298-0709, USA
| |
Collapse
|
33
|
Ferguson BR, Gao WJ. Thalamic Control of Cognition and Social Behavior Via Regulation of Gamma-Aminobutyric Acidergic Signaling and Excitation/Inhibition Balance in the Medial Prefrontal Cortex. Biol Psychiatry 2018; 83:657-669. [PMID: 29373121 PMCID: PMC5862785 DOI: 10.1016/j.biopsych.2017.11.033] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 11/25/2017] [Accepted: 11/28/2017] [Indexed: 11/20/2022]
Abstract
BACKGROUND The mediodorsal thalamus plays a critical role in cognition through its extensive innervation of the medial prefrontal cortex (mPFC), but how the two structures cooperate at the single-cell level to generate associated cognitive functions and other mPFC-dependent behaviors remains elusive. Maintaining the proper balance between excitation and inhibition (E/I balance) is of principal importance for organizing cortical activity. Furthermore, the PFC E/I balance has been implicated in successful execution of multiple PFC-dependent behaviors in both animal research and the context of human psychiatric disorders. METHODS Here, we used a pharmacogenetic strategy to decrease mediodorsal thalamic activity in adult male rats and evaluated the consequences for E/I balance in PFC pyramidal neurons as well as cognition, social interaction, and anxiety. RESULTS We found that dampening mediodorsal thalamic activity caused significant reductions in gamma-aminobutyric acidergic signaling and increased E/I balance in the mPFC and was concomitant with abnormalities in these behaviors. Furthermore, by selectively activating parvalbumin interneurons in the mPFC with a novel pharmacogenetic approach, we restored gamma-aminobutyric acidergic signaling and E/I balance as well as ameliorated all behavioral impairments. CONCLUSIONS These findings underscore the importance of thalamocortical activation of mPFC gamma-aminobutyric acidergic interneurons in a broad range of mPFC-dependent behaviors. Furthermore, they highlight this circuitry as a platform for therapeutic investigation in psychiatric diseases that involve impairments in PFC-dependent behaviors.
Collapse
Affiliation(s)
- Brielle R Ferguson
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Wen-Jun Gao
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, Pennsylvania.
| |
Collapse
|
34
|
Abstract
Both serotonin (5-HT) and stress exert changes in cortical inhibitory tone to shape the activity of cortical networks. Because astrocytes are also known to affect inhibition through established purinergic pathways, we assessed the role of GABA and purinergic pathways with respect to the effects of rapid corticosterone (CORT) and 5-HT on cortical inhibition. We used a paired-pulse paradigm (P1 and P2) in acutely isolated mouse brain slices to evaluate changes in cortical evoked inhibition. Normally, 5-HT decreases the amplitude of the first pulse P1, whereas it increases the amplitude of P2 (increasing frequency transmission). Interestingly, it was observed that CORT application decreased P1 and increased P2 similar to that of 5-HT application. Given that CORT and 5-HT are known to modulate inhibition, we applied the GABAA antagonist bicuculline in the presence of both and found that the increase in P2 and the P2/P1 was lost, providing evidence for a common mechanism involving GABAA receptor signalling. Additional occlusion experiments (ie, 5-HT in presence of CORT and CORT in presence of 5-HT) provide further support for a common mechanism. Because both 5-HT and CORT blocked the increase in P2 and P2/P1 with respect to the other, we suggest 5-HT/CORT already utilise the shared mechanism to affect cortical inhibition. Using low concentrations of the GAPDH inhibitor iodoacetate, as commonly used to selectively disrupt astrocyte metabolism, we found that the increase in P2 and P2/P1 was similarly blocked in response to both CORT and 5-HT. Because astrocyte signalling depends in large part on purinergic pathways, the purinergic contribution was assessed using Ab129 (P2Y antagonist) and SCH 58261 (A2A antagonist). Once again, P2Y and A2A receptor blockade similarly disrupted 5-HT- or CORT-mediated increases in P2 and P2/P1. Taken together, these results support the common involvement of GABAergic and purinergic pathways in the effects of CORT and 5-HT that may also involve astrocytes.
Collapse
Affiliation(s)
- C A Wotton
- Department of Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - E F Quon
- Department of Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - A C Palmer
- Department of Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - L K Bekar
- Department of Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| |
Collapse
|
35
|
Korol SV, Tafreshiha A, Bhandage AK, Birnir B, Jin Z. Insulin enhances GABA A receptor-mediated inhibitory currents in rat central amygdala neurons. Neurosci Lett 2018; 671:76-81. [PMID: 29447952 DOI: 10.1016/j.neulet.2018.02.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 01/23/2018] [Accepted: 02/09/2018] [Indexed: 01/04/2023]
Abstract
Insulin, a pancreatic hormone, can access the central nervous system, activate insulin receptors distributed in selective brain regions and affect various cellular functions such as neurotransmission. We have previously shown that physiologically relevant concentration of insulin potentiates the GABAA receptor-mediated tonic inhibition and reduces excitability of rat hippocampal CA1 neurons. The central nucleus of the amygdala (CeA) comprises heterogeneous neuronal populations that can respond to hormonal stimulus. Using quantitative PCR and immunofluorescent labeling, we report that the mRNA and protein of the insulin receptor are abundantly expressed in the rat CeA. The insulin receptor mRNA is also detected in the CeA from post-mortem human brain samples. Furthermore, our whole-cell patch-clamp recordings show that the application of insulin (5 and 50 nM) selectively enhances the frequency and amplitude of spontaneous inhibitory postsynaptic currents (sIPSCs) in rat CeA neurons. Our findings reveal that GABAergic synaptic transmission is a target in the CeA for insulin receptor signaling that may underlie insulin modulation of emotion- and feeding-related behaviors.
Collapse
Affiliation(s)
- Sergiy V Korol
- Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden
| | - Atieh Tafreshiha
- Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden
| | - Amol K Bhandage
- Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden
| | - Bryndis Birnir
- Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden
| | - Zhe Jin
- Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden.
| |
Collapse
|
36
|
Moehle MS, Pancani T, Byun N, Yohn SE, Wilson GH, Dickerson JW, Remke DH, Xiang Z, Niswender CM, Wess J, Jones CK, Lindsley CW, Rook JM, Conn PJ. Cholinergic Projections to the Substantia Nigra Pars Reticulata Inhibit Dopamine Modulation of Basal Ganglia through the M 4 Muscarinic Receptor. Neuron 2017; 96:1358-1372.e4. [PMID: 29268098 PMCID: PMC5753765 DOI: 10.1016/j.neuron.2017.12.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 10/04/2017] [Accepted: 12/04/2017] [Indexed: 12/16/2022]
Abstract
Cholinergic regulation of dopaminergic inputs into the striatum is critical for normal basal ganglia (BG) function. This regulation of BG function is thought to be primarily mediated by acetylcholine released from cholinergic interneurons (ChIs) acting locally in the striatum. We now report a combination of pharmacological, electrophysiological, optogenetic, chemogenetic, and functional magnetic resonance imaging studies suggesting extra-striatal cholinergic projections from the pedunculopontine nucleus to the substantia nigra pars reticulata (SNr) act on muscarinic acetylcholine receptor subtype 4 (M4) to oppose cAMP-dependent dopamine receptor subtype 1 (D1) signaling in presynaptic terminals of direct pathway striatal spiny projections neurons. This induces a tonic inhibition of transmission at direct pathway synapses and D1-mediated activation of motor activity. These studies provide important new insights into the unique role of M4 in regulating BG function and challenge the prevailing hypothesis of the centrality of striatal ChIs in opposing dopamine regulation of BG output.
Collapse
Affiliation(s)
- Mark S Moehle
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Tristano Pancani
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Nellie Byun
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA
| | - Samantha E Yohn
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - George H Wilson
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA
| | - Johnathan W Dickerson
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Daniel H Remke
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Zixiu Xiang
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Colleen M Niswender
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, NIDDK, NIH, Bethesda, MD, USA
| | - Carrie K Jones
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Craig W Lindsley
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Jerri M Rook
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN, USA.
| |
Collapse
|
37
|
Jamieson BB, Nair BB, Iremonger KJ. Regulation of hypothalamic corticotropin-releasing hormone neurone excitability by oxytocin. J Neuroendocrinol 2017; 29. [PMID: 28872712 DOI: 10.1111/jne.12532] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 02/01/2023]
Abstract
Oxytocin (OT) is a neuropeptide that exerts multiple actions throughout the brain and periphery. Within the brain, OT regulates diverse neural populations, including neural networks controlling responses to stress. Local release of OT within the paraventricular nucleus (PVN) of the hypothalamus has been suggested to regulate stress responses by modulating the excitability of neighbouring corticotropin-releasing hormone (CRH) neurones. However, the mechanisms by which OT regulates CRH neurone excitability are unclear. In the present study, we investigated the morphological relationship between OT and CRH neurones and determined the effects of OT on CRH neurone excitability. Morphological analysis revealed that the processes of OT and CRH neurones were highly intermingled within the PVN, possibly allowing for local cell-to-cell cross-talk. Whole-cell patch-clamp recordings from CRH neurones were used to study the impact of OT on postsynaptic excitability and synaptic innervation. Bath-applied OT did not alter CRH neurone holding current, spiking output or any action potential parameters. Recordings of evoked excitatory and inhibitory postsynaptic currents (EPSCs/IPSCs) revealed no net effect of OT on current amplitude; however, subgroups of CRH neurones appeared to respond differentially to OT. Analysis of spontaneous EPSC events uncovered a significant reduction in spontaneous EPSC frequency but no change in spontaneous EPSC amplitude in response to OT. Together, these data demonstrate that OT exerts a subtle modulation of synaptic transmission onto CRH neurones providing one potential mechanism by which OT could suppress CRH neurone excitability and stress axis activity.
Collapse
Affiliation(s)
- B B Jamieson
- Department of Physiology, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| | - B B Nair
- Department of Physiology, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| | - K J Iremonger
- Department of Physiology, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| |
Collapse
|
38
|
Casalia ML, Howard MA, Baraban SC. Persistent seizure control in epileptic mice transplanted with gamma-aminobutyric acid progenitors. Ann Neurol 2017; 82:530-542. [PMID: 28833459 PMCID: PMC5771437 DOI: 10.1002/ana.25021] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/14/2017] [Accepted: 08/14/2017] [Indexed: 12/19/2022]
Abstract
OBJECTIVE A significant proportion of the more than 50 million people worldwide currently suffering with epilepsy are resistant to antiepileptic drugs (AEDs). As an alternative to AEDs, novel therapies based on cell transplantation offer an opportunity for long-lasting modification of epileptic circuits. To develop such a treatment requires careful preclinical studies in a chronic epilepsy model featuring unprovoked seizures, hippocampal histopathology, and behavioral comorbidities. METHODS Transplantation of progenitor cells from embryonic medial or caudal ganglionic eminence (MGE, CGE) were made in a well-characterized mouse model of status epilepticus-induced epilepsy (systemic pilocarpine). Behavioral testing (handling and open field), continuous video-electroencephalographic (vEEG) monitoring, and slice electrophysiology outcomes were obtained up to 270 days after transplantation (DAT). Post-hoc immunohistochemistry was used to confirm cell identity. RESULTS MGE progenitors transplanted into the hippocampus of epileptic mice rescued handling and open field deficits starting at 60 DAT. In these same mice, an 84% to 88% reduction in seizure activity was observed between 180 and 210 DAT. Inhibitory postsynaptic current frequency, measured on pyramidal neurons in acute hippocampal slices at 270 DAT, was reduced in epileptic mice but restored to naïve levels in epileptic mice receiving MGE transplants. No reduction in seizure activity was observed in epileptic mice receiving intrahippocampal CGE progenitors. INTERPRETATION Our findings demonstrate that transplanted MGE progenitors enhance functional GABA-mediated inhibition, reduce spontaneous seizure frequency, and rescue behavioral deficits in a chronic epileptic animal model more than 6 months after treatment. Ann Neurol 2017;82:530-542.
Collapse
Affiliation(s)
- Mariana L Casalia
- Epilepsy Research Laboratory, Department of Neurological Surgery and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA
| | - MacKenzie A Howard
- Epilepsy Research Laboratory, Department of Neurological Surgery and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA
| | - Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA
| |
Collapse
|
39
|
Chen X, Keramidas A, Lynch JW. Physiological and pharmacological properties of inhibitory postsynaptic currents mediated by α5β1γ2, α5β2γ2 and α5β3γ2 GABA A receptors. Neuropharmacology 2017; 125:243-253. [PMID: 28757051 DOI: 10.1016/j.neuropharm.2017.07.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/18/2017] [Accepted: 07/26/2017] [Indexed: 02/07/2023]
Abstract
α5-containing GABAARs are potential therapeutic targets for clinical conditions including age-related dementia, stroke, schizophrenia, Down syndrome, anaesthetic-induced amnesia, anxiety and pain. α5-containing GABAARs are expressed in layer 5 cortical neurons and hippocampal pyramidal neurons where they mediate both tonic currents and slow inhibitory postsynaptic currents (IPSCs). A range of drugs has been developed to specifically modulate these receptors. The main α5-containing GABAARs that are likely to exist in vivo are the α5β1γ2, α5β2γ2 and α5β3γ2 isoforms. We currently have few clues as to how these isoforms are distributed between synaptic and extrasynaptic compartments or their relative roles in controlling neuronal excitability. Accordingly, the aim of this study was to define the basic biophysical and pharmacological properties of IPSCs mediated by the three isoforms in a hippocampal neuron-HEK293 cell co-culture assay. The IPSC decay time constants were slow (α5β1γ2L: 45 ms; α5β1γ2L: 80 ms; α5β3γ2L: 184 ms) and were largely dominated by the intrinsic channel deactivation rates. By comparing IPSC rise times, we inferred that α5β1γ2L GABAARs are located postsynaptically whereas the other two are predominantly perisynaptic. α5β3γ2L GABAARs alone mediated tonic currents. We quantified the effects of four α5-specific inverse agonists (TB-21007, MRK-016, α5IA and L-655708) on IPSCs mediated by the three isoforms. All compounds selectively inhibited IPSC amplitudes and accelerated IPSC decay rates, albeit with distinct isoform specificities. MRK-016 also significantly accelerated IPSC rise times. These results provide a reference for future studies seeking to identify and characterize the properties of IPSCs mediated by α5-containing GABAAR isoforms in neurons.
Collapse
Affiliation(s)
- Xiumin Chen
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Joseph W Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
| |
Collapse
|
40
|
Yelhekar TD, Druzin M, Johansson S. Contribution of Resting Conductance, GABA A-Receptor Mediated Miniature Synaptic Currents and Neurosteroid to Chloride Homeostasis in Central Neurons. eNeuro 2017; 4:ENEURO.0019-17.2017. [PMID: 28374007 PMCID: PMC5362935 DOI: 10.1523/eneuro.0019-17.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 02/27/2017] [Accepted: 03/12/2017] [Indexed: 01/20/2023] Open
Abstract
Maintenance of a low intraneuronal Cl- concentration, [Cl-]i, is critical for inhibition in the CNS. Here, the contribution of passive, conductive Cl- flux to recovery of [Cl-]i after a high load was analyzed in mature central neurons from rat. A novel method for quantifying the resting Cl- conductance, important for [Cl-]i recovery, was developed and the possible contribution of GABAA and glycine receptors and of ClC-2 channels to this conductance was analyzed. The hypothesis that spontaneous, action potential-independent release of GABA is important for [Cl-]i recovery was tested. [Cl-]i was examined by gramicidin-perforated patch recordings in medial preoptic neurons. Cells were loaded with Cl- by combining GABA or glycine application with a depolarized voltage, and the time course of [Cl-]i was followed by measurements of the Cl- equilibrium potential, as obtained from the current recorded during voltage ramps combined with GABA or glycine application. The results show that passive Cl- flux contributes significantly, in the same order of magnitude as does K+-Cl- cotransporter 2 (KCC2), to [Cl-]i recovery and that Cl- conductance accounts for ∼ 6% of the total resting conductance. A major fraction of this resting Cl- conductance is picrotoxin (PTX)-sensitive and likely due to open GABAA receptors, but ClC-2 channels do not contribute. The results also show that when the decay of GABAA receptor-mediated miniature postsynaptic currents (minis) is slowed by the neurosteroid allopregnanolone, such minis may significantly quicken [Cl-]i recovery, suggesting a possible steroid-regulated role for minis in the control of Cl- homeostasis.
Collapse
Affiliation(s)
- Tushar D Yelhekar
- Department of Integrative Medical Biology, Umeå University , Umeå, SE-901 87, Sweden
| | - Michael Druzin
- Department of Integrative Medical Biology, Umeå University , Umeå, SE-901 87, Sweden
| | - Staffan Johansson
- Department of Integrative Medical Biology, Umeå University , Umeå, SE-901 87, Sweden
| |
Collapse
|
41
|
Oyelami T, Bondt AD, den Wyngaert IV, Hoorde KV, Hoskens L, Shaban H, Kemp JA, Drinkenburg WH. Age-dependent concomitant changes in synaptic dysfunction and GABAergic pathway in the APP/PS1 mouse model. Acta Neurobiol Exp (Wars) 2017; 76:282-293. [PMID: 28094819 DOI: 10.21307/ane-2017-027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Synaptic dysfunction is a well-documented manifestation in animal models of Alzheimer's disease pathology. In this context, numerous studies have documented reduction in the functionality of synapses in various models. In addition, recent research has shed more light on increased excitability and its link to seizures and seizure-like activities in AD patients as well as in mouse models. These reports of hyperexcitability contradict the observed reduction in synaptic function and have been suggested to be as a result of the interplay between inhibitory and excitatory neuronal mechanism. The present study therefore investigates functional deficiency in the inhibitory system as complementary to the identified alterations in the glutamate excitatory pathway in AD. Since synaptic function deficit in AD is typically linked to progression/pathology of the disease, it is important to determine whether the deficits in the GABAergic system are functional and can be directly linked to the pattern of the disruption documented in the glutamate system. To build on previous research in this field, experiments were designed to determine if previously documented synaptic dysfunction in AD models is concomitantly observed with excitation/inhibition imbalance as suggested by observation of seizure and seizure-like pathology in such models. We report changes in synaptic function in aged APPPS1 mice not observable in the younger cohort. These changes in synaptic function are furthermore accompanied by alteration in the GABAergic neurotransmission. Thus, age-dependent alteration in the inhibitory/excitatory balance might underpin the symptomatic changes observed with the progression of Alzheimer's disease pathology including sleep disturbance and epileptic events.
Collapse
Affiliation(s)
- Tutu Oyelami
- Department of Neuroscience, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium; Institute of Neuroscience, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - An De Bondt
- Department of Computational Biology, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - Ilse Van den Wyngaert
- Department of Translational Sciences, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - Kirsten Van Hoorde
- OpenAnalytics NV, Antwerp, Belgium, 5 Institute of Neuroscience, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Luc Hoskens
- Department of Neuroscience, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - Hamdy Shaban
- Department of Neuroscience, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - John A Kemp
- Department of Neuroscience, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - Wilhelmus H Drinkenburg
- Department of Neuroscience, Janssen Research and Development, A Division of Janssen Pharmaceutica NV, Beerse, Belgium,
| |
Collapse
|
42
|
Nakahata Y, Eto K, Murakoshi H, Watanabe M, Kuriu T, Hirata H, Moorhouse AJ, Ishibashi H, Nabekura J. Activation-Dependent Rapid Postsynaptic Clustering of Glycine Receptors in Mature Spinal Cord Neurons. eNeuro 2017; 4:ENEURO.0194-16.2017. [PMID: 28197549 PMCID: PMC5292596 DOI: 10.1523/eneuro.0194-16.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 01/05/2017] [Accepted: 01/17/2017] [Indexed: 12/02/2022] Open
Abstract
Inhibitory synapses are established during development but continue to be generated and modulated in strength in the mature nervous system. In the spinal cord and brainstem, presynaptically released inhibitory neurotransmitter dominantly switches from GABA to glycine during normal development in vivo. While presynaptic mechanisms of the shift of inhibitory neurotransmission are well investigated, the contribution of postsynaptic neurotransmitter receptors to this shift is not fully elucidated. Synaptic clustering of glycine receptors (GlyRs) is regulated by activation-dependent depolarization in early development. However, GlyR activation induces hyperpolarization after the first postnatal week, and little is known whether and how presynaptically released glycine regulates postsynaptic receptors in a depolarization-independent manner in mature developmental stage. Here we developed spinal cord neuronal culture of rodents using chronic strychnine application to investigate whether initial activation of GlyRs in mature stage could change postsynaptic localization of GlyRs. Immunocytochemical analyses demonstrate that chronic blockade of GlyR activation until mature developmental stage resulted in smaller clusters of postsynaptic GlyRs that could be enlarged upon receptor activation for 1 h in the mature stage. Furthermore, live cell-imaging techniques show that GlyR activation decreases its lateral diffusion at synapses, and this phenomenon is dependent on PKC, but neither Ca2+ nor CaMKII activity. These results suggest that the GlyR activation can regulate receptor diffusion and cluster size at inhibitory synapses in mature stage, providing not only new insights into the postsynaptic mechanism of shifting inhibitory neurotransmission but also the inhibitory synaptic plasticity in mature nervous system.
Collapse
Affiliation(s)
- Yoshihisa Nakahata
- Division of Homeostatic Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
| | - Kei Eto
- Division of Homeostatic Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
| | - Hideji Murakoshi
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
- Supportive Center for Brain Research, National Institute for Physiological Science, Okazaki 444-8585, Japan
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
| | - Miho Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
| | - Toshihiko Kuriu
- Department of Neurophysiology, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 769-2193, Japan
| | - Hiromi Hirata
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima 411-8540, Japan
- Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI), Mishima 411-8540, Japan
- Department of Chemistry and Biological Science, Graduate School of Science and Engineering, Aoyama Gakuin University, Sagamihara 252-5258, Japan
| | - Andrew J. Moorhouse
- Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney 2052, Australia
| | - Hitoshi Ishibashi
- Division of Homeostatic Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
- Department of Physiology, Kitasato University School of Allied Health Sciences, Sagamihara 252-0373, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
- CREST, Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
| |
Collapse
|
43
|
Zhang KM, Zhao GY, Zhang BB, Xu Q, Chu CP, Jin H, Qiu DL. Nicotine enhances GABAergic inhibition of oxytocin mRNA-expressing neuron in the hypothalamic paraventricular nucleus in vitro in rats. Neurosci Lett 2016; 638:5-11. [PMID: 27923665 DOI: 10.1016/j.neulet.2016.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 11/22/2016] [Accepted: 12/02/2016] [Indexed: 01/31/2023]
Abstract
We recently found that extracellular administration of nicotine indirectly excited hypothalamic paraventricular nucleus (PVN) corticotropin-releasing hormone (CRH) mRNA-expressing neurons. In this study, we studied the effect of nicotine on PVN oxytocin (OT) mRNA-expressing neuron in vitro in rats, by whole-cell patch-clamp recording technique, immunohistochemistry methods and single-cell reverse-transcription multiplex polymerase chain reaction (SC-RT-mPCR) methods Our results showed that 79.3% (73/92) of the 92 PVN putative magnocellular neurons co-expressed GAPDH mRNA and OT mRNA. Under current-clamp recording conditions, local micro application of nicotine (1-300μM) induced a decrease in spontaneous firing rate accompanied with a hyperpolarization of membrane potential in 76.7% (56/73) of PVN OT mRNA-expressing magnocellular neurons. The nicotine induced inhibition in spontaneous activity of PVN OT mRNA-expressing magnocellular neurons was dose-dependent. The half-inhibitory concentration (IC50) is 2.9μM. The nicotine induced hyperpolarization of PVN OT mRNA-expressing magnocellular neurons was sensitive to GABAA receptor antagonist, SR95531 (10μM) and tetrodotoxin (TTX, 1μM). In addition, local micro application of nicotine induced a significant increase in frequency of spontaneous inhibitory postsynaptic potentials (sIPSPs), but without changes in the sEPSPs amplitude of the OT-mRNA expressing neurons. Biocytin staining confirmed that the nicotine-sensitive OT-mRNA expressing neurons were the PVN magnocellular neurons. These results demonstrated that nicotine enhances the GABAergic inhibition, resulting in a decrease in spontaneous firing rate of the PVN OT-mRNA expressing neurons. These findings suggested that nicotine modulated PVN OT secretion via enhancement of both presynaptic action potential drive and quantal GABA release.
Collapse
Affiliation(s)
- Ke-Min Zhang
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji City, Jilin Province, 133002, China; Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji City, Jilin Province, China
| | - Guo-Yan Zhao
- Department of physiology, Jilin Medical College, Jilin City, Jinlin Province, China
| | - Bin-Bin Zhang
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji City, Jilin Province, 133002, China; Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji City, Jilin Province, China
| | - Qi Xu
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji City, Jilin Province, 133002, China
| | - Chun-Ping Chu
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji City, Jilin Province, 133002, China
| | - Hua Jin
- Department of Nephrology, Affiliated Hospital of Yanbian University, Yanji City, Jilin Province, China.
| | - De-Lai Qiu
- Key Laboratory of Cellular Function and Pharmacology of Jilin Province, Yanbian University, Yanji City, Jilin Province, 133002, China; Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji City, Jilin Province, China.
| |
Collapse
|
44
|
Li YC, Yang SS, Gao WJ. Disruption of Akt signaling decreases dopamine sensitivity in modulation of inhibitory synaptic transmission in rat prefrontal cortex. Neuropharmacology 2016; 108:403-14. [PMID: 27163190 DOI: 10.1016/j.neuropharm.2016.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 04/28/2016] [Accepted: 05/05/2016] [Indexed: 11/18/2022]
Abstract
Akt is a serine/threonine kinase, which is dramatically reduced in the prefrontal cortex (PFC) of patients with schizophrenia, and a deficiency in Akt1 results in PFC function abnormalities. Although the importance of Akt in dopamine (DA) transmission is well established, how impaired Akt signaling affects the DA modulation of synaptic transmission in the PFC has not been characterized. Here we show that Akt inhibitors significantly decreased receptor sensitivity to DA by shifting DA modulation of GABAA receptor-mediated inhibitory postsynaptic currents (IPSCs) in prefrontal cortical neurons. Akt inhibition caused a significant decrease in synaptic dopamine D2 receptor (D2R) levels with high-dose DA exposure. In addition, Akt inhibition failed to affect DA modulation of IPSCs after blockade of β-arrestin 2. β-arrestin 2-mediated interaction of clathrin with D2R was enhanced by co-application of a Akt inhibitor and DA. Taken together, the reduced response in DA modulation of inhibitory transmission mainly involved β-arrestin 2-dependent D2R desensitization.
Collapse
Affiliation(s)
- Yan-Chun Li
- Department of Neurobiology & Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Sha-Sha Yang
- Department of Neurobiology & Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Wen-Jun Gao
- Department of Neurobiology & Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA.
| |
Collapse
|
45
|
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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
46
|
Schindler AG, Soden ME, Zweifel LS, Clark JJ. Reversal of Alcohol-Induced Dysregulation in Dopamine Network Dynamics May Rescue Maladaptive Decision-making. J Neurosci 2016; 36:3698-708. [PMID: 27030756 PMCID: PMC4812130 DOI: 10.1523/jneurosci.4394-15.2016] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/23/2016] [Accepted: 02/25/2016] [Indexed: 11/21/2022] Open
Abstract
Alcohol is the most commonly abused substance among adolescents, promoting the development of substance use disorders and compromised decision-making in adulthood. We have previously demonstrated, with a preclinical model in rodents, that adolescent alcohol use results in adult risk-taking behavior that positively correlates with phasic dopamine transmission in response to risky options, but the underlying mechanisms remain unknown. Here, we show that adolescent alcohol use may produce maladaptive decision-making through a disruption in dopamine network dynamics via increased GABAergic transmission within the ventral tegmental area (VTA). Indeed, we find that increased phasic dopamine signaling after adolescent alcohol use is attributable to a midbrain circuit, including the input from the pedunculopontine tegmentum to the VTA. Moreover, we demonstrate that VTA dopamine neurons from adult rats exhibit enhanced IPSCs after adolescent alcohol exposure corresponding to decreased basal dopamine levels in adulthood that negatively correlate with risk-taking. Building on these findings, we develop a model where increased inhibitory tone on dopamine neurons leads to a persistent decrease in tonic dopamine levels and results in a potentiation of stimulus-evoked phasic dopamine release that may drive risky choice behavior. Based on this model, we take a pharmacological approach to the reversal of risk-taking behavior through normalization of this pattern in dopamine transmission. These results isolate the underlying circuitry involved in alcohol-induced maladaptive decision-making and identify a novel therapeutic target. SIGNIFICANCE STATEMENT One of the primary problems resulting from chronic alcohol use is persistent, maladaptive decision-making that is associated with ongoing addiction vulnerability and relapse. Indeed, studies with the Iowa Gambling Task, a standard measure of risk-based decision-making, have reliably shown that alcohol-dependent individuals make riskier, more maladaptive choices than nondependent individuals, even after periods of prolonged abstinence. Using a preclinical model, in the current work, we identify a selective disruption in dopamine network dynamics that may promote maladaptive decision-making after chronic adolescent alcohol use and demonstrate its pharmacological reversal in adulthood. Together, these results highlight a novel neural mechanism underlying heightened risk-taking behavior in alcohol-dependent individuals and provide a potential therapeutic target for further investigation.
Collapse
Affiliation(s)
| | - Marta E Soden
- Departments of Psychiatry and Behavioral Sciences and Pharmacology, University of Washington, Seattle, Washington 98195
| | - Larry S Zweifel
- Departments of Psychiatry and Behavioral Sciences and Pharmacology, University of Washington, Seattle, Washington 98195
| | | |
Collapse
|
47
|
Fuenzalida M, Espinoza C, Pérez MÁ, Tapia-Rojas C, Cuitino L, Brandan E, Inestrosa NC. Wnt signaling pathway improves central inhibitory synaptic transmission in a mouse model of Duchenne muscular dystrophy. Neurobiol Dis 2015; 86:109-20. [PMID: 26626079 DOI: 10.1016/j.nbd.2015.11.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/02/2015] [Accepted: 11/23/2015] [Indexed: 02/01/2023] Open
Abstract
The dystrophin-associated glycoprotein complex (DGC) that connects the cytoskeleton, plasma membrane and the extracellular matrix has been related to the maintenance and stabilization of channels and synaptic receptors, which are both essential for synaptogenesis and synaptic transmission. The dystrophin-deficient (mdx) mouse model of Duchenne muscular dystrophy (DMD) exhibits a significant reduction in hippocampal GABA efficacy, which may underlie the altered synaptic function and abnormal hippocampal long-term plasticity exhibited by mdx mice. Emerging studies have implicated Wnt signaling in the modulation of synaptic efficacy, neuronal plasticity and cognitive function. We report here that the activation of the non-canonical Wnt-5a pathway and Andrographolide, improves hippocampal mdx GABAergic efficacy by increasing the number of inhibitory synapses and GABA(A) receptors or GABA release. These results indicate that Wnt signaling modulates GABA synaptic efficacy and could be a promising novel target for DMD cognitive therapy.
Collapse
Affiliation(s)
- Marco Fuenzalida
- Centro de Neurobiología y Plasticidad Cerebral, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
| | - Claudia Espinoza
- Centro de Neurobiología y Plasticidad Cerebral, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Miguel Ángel Pérez
- Centro de Neurobiología y Plasticidad Cerebral, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Cheril Tapia-Rojas
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Loreto Cuitino
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Enrique Brandan
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nibaldo C Inestrosa
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Centre for Healthy Brain Ageing, School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, Australia; Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.
| |
Collapse
|
48
|
Borgkvist A, Avegno EM, Wong MY, Kheirbek MA, Sonders MS, Hen R, Sulzer D. Loss of Striatonigral GABAergic Presynaptic Inhibition Enables Motor Sensitization in Parkinsonian Mice. Neuron 2015; 87:976-88. [PMID: 26335644 DOI: 10.1016/j.neuron.2015.08.022] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 05/14/2015] [Accepted: 08/12/2015] [Indexed: 01/28/2023]
Abstract
Degeneration of dopamine (DA) neurons in Parkinson's disease (PD) causes hypokinesia, but DA replacement therapy can elicit exaggerated voluntary and involuntary behaviors that have been attributed to enhanced DA receptor sensitivity in striatal projection neurons. Here we reveal that in hemiparkinsonian mice, striatal D1 receptor-expressing medium spiny neurons (MSNs) directly projecting to the substantia nigra reticulata (SNr) lose tonic presynaptic inhibition by GABAB receptors. The absence of presynaptic GABAB response potentiates evoked GABA release from MSN efferents to the SNr and drives motor sensitization. This alternative mechanism of sensitization suggests a synaptic target for PD pharmacotherapy.
Collapse
Affiliation(s)
- Anders Borgkvist
- Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Elizabeth M Avegno
- Department of Pharmacology, Columbia University, New York, NY 10032, USA
| | - Minerva Y Wong
- Department of Pharmacology, Columbia University, New York, NY 10032, USA
| | - Mazen A Kheirbek
- Department of Psychiatry, Columbia University, New York, NY 10032, USA
| | - Mark S Sonders
- Department of Neurology, Columbia University, New York, NY 10032, USA; Department of Psychiatry, Columbia University, New York, NY 10032, USA
| | - Rene Hen
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - David Sulzer
- Department of Neurology, Columbia University, New York, NY 10032, USA; Department of Pharmacology, Columbia University, New York, NY 10032, USA; Department of Psychiatry, Columbia University, New York, NY 10032, USA; New York State Psychiatric Institute, New York, NY 10032, USA.
| |
Collapse
|
49
|
Sasajima H, Miyazono S, Noguchi T, Kashiwayanagi M. Intranasal administration of rotenone in mice attenuated olfactory functions through the lesion of dopaminergic neurons in the olfactory bulb. Neurotoxicology 2015; 51:106-15. [PMID: 26493152 DOI: 10.1016/j.neuro.2015.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 09/14/2015] [Accepted: 10/13/2015] [Indexed: 12/20/2022]
Abstract
Many environmental chemicals are thought to affect brain function. It was reported that chemicals in the nasal cavity directly reach the brain through the connection between olfactory neurons and the olfactory bulb (OB). In this 'olfactory transport,' xenobiotics absorbed at the nasal mucosa reach the brain by bypassing some physical barriers and defenses, and thus olfactory transport is suspected to be a vulnerable mechanism of the brain against invasion threats of environmental chemicals. In this study, we focused on the neuronal toxicity of rotenone administered intranasally to mice. The results showed that the mice that were administered rotenone had attenuated olfactory functions. We also found that intranasally administered rotenone induced acute mitochondrial stress at the OB. The repeated administration of rotenone resulted in a decrease in the number of dopaminergic neurons, which are inhibitory interneurons in the OB. Taken together, our findings suggest that the inhalation of environmental toxins induces the neurodegeneration of cranial neurons through olfactory transport, and that olfactory dysfunction may be induced as an earliest symptom of neurodegeneration caused by inhaled neurotoxins.
Collapse
Affiliation(s)
- Hitoshi Sasajima
- Department of Physiology, Division of Sensory Physiology, Asahikawa Medical University, Asahikawa, Japan
| | - Sadaharu Miyazono
- Department of Physiology, Division of Sensory Physiology, Asahikawa Medical University, Asahikawa, Japan
| | - Tomohiro Noguchi
- Department of Physiology, Division of Sensory Physiology, Asahikawa Medical University, Asahikawa, Japan
| | - Makoto Kashiwayanagi
- Department of Physiology, Division of Sensory Physiology, Asahikawa Medical University, Asahikawa, Japan.
| |
Collapse
|
50
|
Hipólito L, Wilson-Poe A, Campos-Jurado Y, Zhong E, Gonzalez-Romero J, Virag L, Whittington R, Comer SD, Carlton SM, Walker BM, Bruchas MR, Morón JA. Inflammatory Pain Promotes Increased Opioid Self-Administration: Role of Dysregulated Ventral Tegmental Area μ Opioid Receptors. J Neurosci 2015; 35:12217-31. [PMID: 26338332 PMCID: PMC4556787 DOI: 10.1523/jneurosci.1053-15.2015] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 07/28/2015] [Accepted: 07/29/2015] [Indexed: 01/02/2023] Open
Abstract
Pain management in opioid abusers engenders ethical and practical difficulties for clinicians, often resulting in pain mismanagement. Although chronic opioid administration may alter pain states, the presence of pain itself may alter the propensity to self-administer opioids, and previous history of drug abuse comorbid with chronic pain promotes higher rates of opioid misuse. Here, we tested the hypothesis that inflammatory pain leads to increased heroin self-administration resulting from altered mu opioid receptor (MOR) regulation of mesolimbic dopamine (DA) transmission. To this end, the complete Freund's adjuvant (CFA) model of inflammation was used to assess the neurochemical and functional changes induced by inflammatory pain on MOR-mediated mesolimbic DA transmission and on rat intravenous heroin self-administration under fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement. In the presence of inflammatory pain, heroin intake under an FR schedule was increased for high, but attenuated for low, heroin doses with concomitant alterations in mesolimbic MOR function suggested by DA microdialysis. Consistent with the reduction in low dose FR heroin self-administration, inflammatory pain reduced motivation for a low dose of heroin, as measured by responding under a PR schedule of reinforcement, an effect dissociable from high heroin dose PR responding. Together, these results identify a connection between inflammatory pain and loss of MOR function in the mesolimbic dopaminergic pathway that increases intake of high doses of heroin. These findings suggest that pain-induced loss of MOR function in the mesolimbic pathway may promote opioid dose escalation and contribute to opioid abuse-associated phenotypes. SIGNIFICANCE STATEMENT This study provides critical new insights that show that inflammatory pain alters heroin intake through a desensitization of MORs located within the VTA. These findings expand our knowledge of the interactions between inflammatory pain and opioid abuse liability, and should help to facilitate the development of novel and safer opioid-based strategies for treating chronic pain.
Collapse
Affiliation(s)
- Lucia Hipólito
- Department of Anesthesiology, Columbia University, New York, New York 10032
| | | | - Yolanda Campos-Jurado
- Departament de Farmàcia i Tecnología Farmacèutica, Facultat de Farmàcia, Universitat de Farmàcia, 46100 Burjassot, València, Spain
| | - Elaine Zhong
- Department of Anesthesiology, Columbia University, New York, New York 10032
| | | | - Laszlo Virag
- Department of Anesthesiology, Columbia University, New York, New York 10032
| | - Robert Whittington
- Department of Anesthesiology, Columbia University, New York, New York 10032
| | - Sandra D Comer
- Department of Psychiatry, Division on Substance Abuse, New York State Psychiatric Institute, College of Physicians and Surgeons of Columbia University, New York, New York 10032
| | - Susan M Carlton
- Department of Neuroscience & Cell Biology, University of Texas Medical Branch Galveston, Galveston, Texas 77555
| | - Brendan M Walker
- Department of Psychology and Graduate Program in Neuroscience, Washington State University, Pullman, Washington 99164, and
| | - Michael R Bruchas
- Department of Anesthesiology and Department of Anatomy and Neurobiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Jose A Morón
- Department of Anesthesiology, Columbia University, New York, New York 10032,
| |
Collapse
|