1
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Tacke C, Bischoff AM, Harb A, Vafadari B, Hülsmann S. Angiotensin II increases respiratory rhythmic activity in the preBötzinger complex without inducing astroglial calcium signaling. Front Cell Neurosci 2023; 17:1111263. [PMID: 36816850 PMCID: PMC9932970 DOI: 10.3389/fncel.2023.1111263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/17/2023] [Indexed: 02/05/2023] Open
Abstract
Angiotensin II (Ang II) is the primary modulator of the renin-angiotensin system and has been widely studied for its effect on the cardiovascular system. While a few studies have also indicated an involvement of Ang II in the regulation of breathing, very little is known in this regard and its effect on brainstem respiratory regions such as the preBötzinger complex (preBötC), the kernel for inspiratory rhythm generation, has not been investigated yet. This study reports that Ang II temporarily increases phrenic nerve activity in the working heart-brainstem preparation, indicating higher central respiratory drive. Previous studies have shown that the carotid body is involved in mediating this effect and we revealed that the preBötC also plays a part, using acute slices of the brainstem. It appears that Ang II is increasing the respiratory drive in an AT1R-dependent manner by optimizing the interaction of inhibitory and excitatory neurons of the preBötC. Thus, Ang II-mediated effects on the preBötC are potentially involved in dysregulating breathing in patients with acute lung injury.
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2
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Souza MM, Vechiato FMV, Debarba LK, Leao RM, Dias MVS, Pereira AA, Cruz JC, Elias LLK, Antunes-Rodrigues J, Ruginsk SG. Effects of Hyperosmolality on Hypothalamic Astrocytic Area, mRNA Expression and Glutamate Balance In Vitro. Neuroscience 2020; 442:286-295. [PMID: 32599125 DOI: 10.1016/j.neuroscience.2020.06.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 11/17/2022]
Abstract
During prolonged dehydration, body fluid homeostasis is challenged by extracellular fluid (ECF) hyperosmolality, which induce important functional changes in the hypothalamus, in parallel with other effector responses, such as the activation of the local renin-angiotensin system (RAS). Therefore, in the present study we investigated the role of sodium-driven ECF hyperosmolality on glial fibrillary acid protein (GFAP) immunoreactivity and protein expression, membrane capacitance, mRNA expression of RAS components and glutamate balance in cultured hypothalamic astrocytes. Our data show that hypothalamic astrocytes respond to increased hyperosmolality with a similar decrease in GFAP expression and membrane capacitance, indicative of reduced cellular area. Hyperosmolality also downregulates the transcript levels of angiotensinogen and both angiotensin-converting enzymes, whereas upregulates type 1a angiotensin II receptor mRNA. Incubation with hypertonic solution also decreases the immunoreactivity to the membrane glutamate/aspartate transporter (GLAST) as well as tritiated-aspartate uptake by astrocytes. This latter effect is completely restored to basal levels when astrocytes previously exposed to hypertonicity are incubated under isotonic conditions. Together with a direct effect on two important local signaling systems (glutamate and RAS), these synaptic rearrangements driven by astrocytes may accomplish for a coordinated increase in the excitatory drive onto the hypothalamic neurosecretory system, ultimately culminating with increased AVP release in response to hyperosmolality.
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Affiliation(s)
- M M Souza
- Department of Physiological Sciences, Biomedical Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - F M V Vechiato
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - L K Debarba
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - R M Leao
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - M V S Dias
- Natural Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - A A Pereira
- Food and Drugs Department, Pharmaceutical Sciences Faculty, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - J C Cruz
- Biotechnology Center, Department of Biotechnology, Federal University of Paraiba, Joao Pessoa, Paraiba, Brazil
| | - L L K Elias
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - J Antunes-Rodrigues
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - S G Ruginsk
- Department of Physiological Sciences, Biomedical Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
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3
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Sumners C, Alleyne A, Rodríguez V, Pioquinto DJ, Ludin JA, Kar S, Winder Z, Ortiz Y, Liu M, Krause EG, de Kloet AD. Brain angiotensin type-1 and type-2 receptors: cellular locations under normal and hypertensive conditions. Hypertens Res 2019; 43:281-295. [PMID: 31853042 DOI: 10.1038/s41440-019-0374-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/25/2019] [Accepted: 11/02/2019] [Indexed: 12/15/2022]
Abstract
Brain angiotensin-II (Ang-II) type-1 receptors (AT1Rs), which exert profound effects on normal cardiovascular, fluid, and metabolic homeostasis, are overactivated in and contribute to chronic sympathoexcitation and hypertension. Accumulating evidence indicates that the activation of Ang-II type-2 receptors (AT2Rs) in the brain exerts effects that are opposite to those of AT1Rs, lowering blood pressure, and reducing hypertension. Thus, it would be interesting to understand the relative cellular localization of AT1R and AT2R in the brain under normal conditions and whether this localization changes during hypertension. Here, we developed a novel AT1aR-tdTomato reporter mouse strain in which the location of brain AT1aR was largely consistent with that determined in the previous studies. This AT1aR-tdTomato reporter mouse strain was crossed with our previously described AT2R-eGFP reporter mouse strain to yield a novel dual AT1aR/AT2R reporter mouse strain, which allowed us to determine that AT1aR and AT2R are primarily localized to different populations of neurons in brain regions controlling cardiovascular, fluid, and metabolic homeostasis. Using the individual AT1aR-tdTomato reporter mice, we also demonstrated that during hypertension induced by the administration of deoxycorticosterone acetate-salt, there was no shift in the expression of AT1aR from neurons to microglia or astrocytes in the paraventricular nucleus, a brain area important for sympathetic regulation. Using AT2R-eGFP reporter mice under similar hypertensive conditions, we demonstrated that the same was true of AT2R expression in the nucleus of the solitary tract (NTS), an area critical for baroreflex control. Collectively, these findings provided a novel means to assess the colocalization of AT1R and AT2R in the brain and a novel view of their cellular localization in hypertension.
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Affiliation(s)
- Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Amy Alleyne
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Vermalí Rodríguez
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - David J Pioquinto
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Jacob A Ludin
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Shormista Kar
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Zachary Winder
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA.,Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Yuma Ortiz
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Meng Liu
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Eric G Krause
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA.
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Chmiel-Perzyńska I, Perzyński A, Olajossy B, Gil-Kulik P, Kocki J, Urbańska EM. Losartan Reverses Hippocampal Increase of Kynurenic Acid in Type 1 Diabetic Rats: A Novel Procognitive Aspect of Sartan Action. J Diabetes Res 2019; 2019:4957879. [PMID: 31737685 PMCID: PMC6815597 DOI: 10.1155/2019/4957879] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 09/13/2019] [Indexed: 11/18/2022] Open
Abstract
Patients with diabetes mellitus (DM) type 1 and 2 are at a higher risk of cognitive decline and dementia; however, the underlying pathology is poorly understood. Kynurenic acid (KYNA), endogenous kynurenine metabolite, displays pleiotropic effects, including a blockade of glutamatergic and cholinergic receptors. Apart from well-known glial origin, kynurenic acid is robustly synthesized in the endothelium and its serum levels correlate with homocysteine, a risk factor for cognitive decline. Studies in an experimental DM model suggest that a selective, hippocampal increase of the kynurenic acid level may be an important factor contributing to diabetes-related cognitive impairment. The aim of this study was to assess the effects of chronic, four-week administration of losartan, angiotensin receptor blocker (ARB), on the brain KYNA in diabetic rats. Chromatographic and rt-PCR techniques were used to measure the level of KYNA and the expression of genes encoding kynurenine aminotransferases, KYNA biosynthetic enzymes, in the hippocampi of rats with streptozotocin-induced DM, treated with losartan. The effect of losartan on KYNA synthesis de novo was also evaluated in vitro, in brain cortical slices. The hippocampal increase of KYNA content occurred in diabetic rats treated and nontreated with insulin. Losartan did not affect KYNA levels when administered per se to naïve or diabetic animals but normalized KYNA content in diabetic rats receiving concomitantly insulin. The expression of CCBL1 (kat 1), AADAT (kat 2), and KAT3 (kat 3) genes did not differ between analyzed groups. Low concentrations of losartan did not affect KYNA production in vitro. The neuroprotective effect of ARBs in diabetic individuals may be, at least partially, linked to modulation of KYNA metabolism. The ability of ARB to modulate synthesis of KYNA in diabetic brain does not seem to result from changed expression of genes encoding KATs. We propose possible involvement of angiotensin AT4 receptors in the observed action of losartan.
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Affiliation(s)
- Iwona Chmiel-Perzyńska
- Department of Experimental and Clinical Pharmacology, Medical University in Lublin, Poland
| | - Adam Perzyński
- II Department of Psychiatry and Psychiatry Rehabilitation, Medical University in Lublin, Poland
| | - Bartosz Olajossy
- Internal Medicine and Cardiology Clinic, 1st Military Clinical Hospital in Lublin, Poland
| | - Paulina Gil-Kulik
- Department of Clinical Genetics, Medical University in Lublin, Poland
| | - Janusz Kocki
- Department of Clinical Genetics, Medical University in Lublin, Poland
| | - Ewa M. Urbańska
- Department of Experimental and Clinical Pharmacology, Medical University in Lublin, Poland
- Laboratory of Cellular and Molecular Pharmacology, Department of Experimental and Clinical Pharmacology, Medical University in Lublin, Poland
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5
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Hong-Qiang H, Mang-Qiao S, Fen X, Shan-Shan L, Hui-Juan C, Wu-Gang H, Wen-Jun Y, Zheng-Wu P. Sirt1 mediates improvement of isoflurane-induced memory impairment following hyperbaric oxygen preconditioning in middle-aged mice. Physiol Behav 2018; 195:1-8. [PMID: 30040951 DOI: 10.1016/j.physbeh.2018.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 07/20/2018] [Accepted: 07/20/2018] [Indexed: 01/04/2023]
Abstract
Hyperbaric oxygen (HBO) preconditioning (PC) has been suggested as a feasible method to provide neuroprotection from postoperative cognitive dysfunction (POCD). However, whether HBO-PC can ameliorate cognitive deficits induced by isoflurane, and the possible mechanism by which it may exert its effect, has not yet been clarified. In the present study, middle-aged mice were exposed to isoflurane anesthesia (1.5 minimal alveolar concentration [MAC]) for 2 h to establish a POCD model. After HBO preconditioning, cognitive function and expression of hippocampal sirtuin 1 (Sirt1), nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) were evaluated 24 h following isoflurane treatment, in the presence or absence of Sirt1 knockdown by short hairpin RNA (shRNA). HBO preconditioning increased the expression of Sirt1, Nrf2, and HO-1 and ameliorated memory dysfunction. Meanwhile, Sirt1 knockdown inhibited the expression of Nrf2 and HO-1 and attenuated the HBO preconditioning-associated memory improvement. Our results suggest that the application of HBO preconditioning is a useful treatment for POCD, and that Sirt1 may be a potential molecular target for POCD therapy.
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Affiliation(s)
- Hu Hong-Qiang
- Department of Anesthesiology, PLA No. 174 Hospital, Chenggong Hospital Affiliated to Xiamen University, Xiamen, Fujian 361003, China
| | - Shu Mang-Qiao
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China; Department of Psychiatry, Changan Hospital, Xi'an 710016, China
| | - Xue Fen
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Liu Shan-Shan
- Department of Anesthesiology, PLA No. 174 Hospital, Chenggong Hospital Affiliated to Xiamen University, Xiamen, Fujian 361003, China
| | - Cao Hui-Juan
- Department of Anesthesiology, PLA No. 174 Hospital, Chenggong Hospital Affiliated to Xiamen University, Xiamen, Fujian 361003, China
| | - Hou Wu-Gang
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Yan Wen-Jun
- Department of Anesthesiology, Gansu Provincial Hospital, Lanzhou 730000, China.
| | - Peng Zheng-Wu
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
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6
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O’Connor AT, Clark MA. Astrocytes and the Renin Angiotensin System: Relevance in Disease Pathogenesis. Neurochem Res 2018; 43:1297-1307. [DOI: 10.1007/s11064-018-2557-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/21/2018] [Accepted: 05/23/2018] [Indexed: 12/29/2022]
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7
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Orphan receptor GPR37L1 contributes to the sexual dimorphism of central cardiovascular control. Biol Sex Differ 2018; 9:14. [PMID: 29625592 PMCID: PMC5889568 DOI: 10.1186/s13293-018-0173-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 03/27/2018] [Indexed: 11/29/2022] Open
Abstract
Background Over 100 mammalian G protein-coupled receptors are yet to be matched with endogenous ligands; these so-called orphans are prospective drug targets for the treatment of disease. GPR37L1 is one such orphan, abundant in the brain and detectable as mRNA in the heart and kidney. GPR37L1 ablation was reported to cause hypertension and left ventricular hypertrophy, and thus, we sought to further define the role of GPR37L1 in blood pressure homeostasis. Methods We investigated the cardiovascular effects of GPR37L1 using wild-type (GPR37L1wt/wt) and null (GPR37L1KO/KO) mice established on a C57BL/6J background, both under baseline conditions and during AngII infusion. We profiled GPR37L1 tissue expression, examining the endogenous receptor by immunoblotting and a β-galactosidase reporter mouse by immunohistochemistry. Results GPR37L1 protein was abundant in the brain but not detectable in the heart and kidney. We measured blood pressure in GPR37L1wt/wt and GPR37L1KO/KO mice and found that deletion of GPR37L1 causes a female-specific increase in systolic, diastolic, and mean arterial pressures. When challenged with short-term AngII infusion, only male GPR37L1KO/KO mice developed exacerbated left ventricular hypertrophy and evidence of heart failure, while the female GPR37L1KO/KO mice were protected from cardiac fibrosis. Conclusions Despite its absence in the heart and kidney, GPR37L1 regulates baseline blood pressure in female mice and is crucial for cardiovascular compensatory responses in males. The expression of GPR37L1 in the brain, yet absence from peripheral cardiovascular tissues, suggests this orphan receptor is a hitherto unknown contributor to central cardiovascular control. Electronic supplementary material The online version of this article (10.1186/s13293-018-0173-y) contains supplementary material, which is available to authorized users.
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8
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Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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9
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Verkhratsky A, Nedergaard M. Physiology of Astroglia. Physiol Rev 2018; 98:239-389. [PMID: 29351512 PMCID: PMC6050349 DOI: 10.1152/physrev.00042.2016] [Citation(s) in RCA: 898] [Impact Index Per Article: 149.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/22/2017] [Accepted: 04/27/2017] [Indexed: 02/07/2023] Open
Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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10
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Zhou CH, Zhang YH, Xue F, Xue SS, Chen YC, Gu T, Peng ZW, Wang HN. Isoflurane exposure regulates the cell viability and BDNF expression of astrocytes via upregulation of TREK‑1. Mol Med Rep 2017; 16:7305-7314. [PMID: 28944872 PMCID: PMC5865860 DOI: 10.3892/mmr.2017.7547] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 07/26/2017] [Indexed: 12/17/2022] Open
Abstract
Neonatal isoflurane exposure in rodents disrupts hippocampal cognitive functions, including learning and memory, and astrocytes may have an important role in this process. However, the molecular mechanisms underlying this disruption are not fully understood. The present study investigated the role of TWIK-related K+ channel (TREK-1) in isoflurane-induced cognitive impairment. Lentiviruses were used to overexpress or knockdown TREK-1 in astrocytes exposed to increasing concentrations of isoflurane or O2 for 2 h. Subsequently, the mRNA and protein expression of brain-derived neurotrophic factor (BDNF), caspase-3, Bcl-2-associated X (Bax) and TREK-1 was measured by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. In addition, cell viability was assessed by a 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium monosodium salt assay. The results demonstrated that, prior to manipulating TREK-1, isoflurane significantly decreased the cell viability and BDNF expression, and increased Bax, caspase-3 and TREK-1 expression was observed. However, TREK-1 overexpression in astrocytes significantly downregulated BDNF expression, and upregulated Bax and caspase-3 expression. Furthermore, lentiviral-mediated short hairpin RNA knockdown of TREK-1 effectively inhibited the isoflurane-induced changes in BDNF, Bax and caspase-3 expression. Taken together, the results of the present study indicate that isoflurane-induced cell damage in astrocytes may be associated with TREK-1-mediated inhibition of BDNF and provide a reference for the safe use of isoflurane anesthesia in infants and children.
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Affiliation(s)
- Cui-Hong Zhou
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Ya-Hong Zhang
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Fen Xue
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Shan-Shan Xue
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Yun-Chun Chen
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Ting Gu
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Zheng-Wu Peng
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Hua-Ning Wang
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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11
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Affiliation(s)
- Pablo Nakagawa
- From the Department of Pharmacology, UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City
| | - Curt D Sigmund
- From the Department of Pharmacology, UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City.
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12
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Biased agonism/antagonism at the AngII-AT1 receptor: Implications for adrenal aldosterone production and cardiovascular therapy. Pharmacol Res 2017; 125:14-20. [PMID: 28511989 DOI: 10.1016/j.phrs.2017.05.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 05/03/2017] [Accepted: 05/11/2017] [Indexed: 12/23/2022]
Abstract
Many of the effects of angiotensin II (AngII), including adrenocortical aldosterone release, are mediated by the AngII type 1 receptor (AT1R), a receptor with essential roles in cardiovascular homeostasis. AT1R belongs to the G protein-coupled receptor (GPCR) superfamily, mainly coupling to the Gq/11 type of G proteins. However, it also signals through βarrestins, oftentimes in parallel to eliciting G protein-dependent signaling. This has spurred infinite possibilities for cardiovascular pharmacology, since various beneficial effects are purportedly exerted by AT1R via βarrestins, unlike AT1R-induced G protein-mediated pathways that usually result in damaging cardiovascular effects, including hypertension and aldosterone elevation. Over the past decade however, a number of studies from our group and others have suggested that AT1R-induced βarrestin signaling can also be damaging for the heart, similarly to the G protein-dependent one, with regard to aldosterone regulation. Additionally, AT1R-induced βarrestin signaling in astrocytes from certain areas of the brain may also play a significant role in central regulation of blood pressure and hypertension pathogenesis. These findings have provided the impetus for testing available angiotensin receptor blockers (ARBs) in their efficacy towards blocking both routes (i.e. both G protein- and βarrestin-dependent) of AT1R signaling in vitro and in vivo and also have promoted structure-activity relationship (SAR) studies for the AngII molecule in terms of βarrestin signaling to certain cellular effects, e.g. adrenal aldosterone production. In the present review, we will recount all of these recent studies on adrenal and astrocyte AT1R-dependent βarrestin signaling while underlining their implications for cardiovascular pathophysiology and therapy.
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13
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Wakayama K, Shimamura M, Suzuki JI, Watanabe R, Koriyama H, Akazawa H, Nakagami H, Mochizuki H, Isobe M, Morishita R. Angiotensin II Peptide Vaccine Protects Ischemic Brain Through Reducing Oxidative Stress. Stroke 2017; 48:1362-1368. [DOI: 10.1161/strokeaha.116.016269] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 01/21/2017] [Accepted: 02/06/2017] [Indexed: 01/20/2023]
Abstract
Background and Purpose—
Medication nonadherence is one of major risk factors for the poor outcome in ischemic stroke. Vaccination is expected to solve such a problem because of its long-lasting effects, but its effect on ischemic brain damage is still unknown. Here, we focused on vaccination for renin–angiotensin system and examined the effects of angiotensin II (Ang II) peptide vaccine in permanent middle cerebral artery occlusion model in rats.
Methods—
Male Wistar rats were exposed to permanent middle cerebral artery occlusion after 3× injections of Ang II peptide vaccine, and the serum or brain level of anti–Ang II antibody was examined. The effects of the vaccine were evaluated by differences in infarction volume, brain renin–angiotensin system components, and markers for neurodegeneration and oxidative stress.
Results—
Ang II vaccination successfully produced anti–Ang II antibodies in serum without concomitant change in blood pressure. Sufficient production of serum anti–Ang II antibody led to reduction of infarct volume and induced the penetration of anti–Ang II antibody in ischemic hemisphere, with suppressed expression of Ang II type 1 receptor mRNA. Vaccinated rats with sufficient antibody production showed the reduction of Fluoro-Jade B–positive cells, spectrin fragmentation, 4-hydroxynonenal-positive cells, and
Nox 2
mRNA expression.
Conclusions—
Our findings indicate that Ang II vaccination exerts neuroprotective and antioxidative effects in cerebral ischemia, with renin–angiotensin system blockade by penetration of anti–Ang II antibodies into ischemic brain lesion. Ang II peptide vaccination could be a promising approach to treat ischemic stroke.
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Affiliation(s)
- Kouji Wakayama
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Munehisa Shimamura
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Jun-ichi Suzuki
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Ryo Watanabe
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Hiroshi Koriyama
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Hiroshi Akazawa
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Hironori Nakagami
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Hideki Mochizuki
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Mitsuaki Isobe
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
| | - Ryuichi Morishita
- From the Department of Advanced Clinical Science and Therapeutics (K.W., J.-i.S.) and Department of Cardiovascular Medicine (H.A.), Graduate School of Medicine, The University of Tokyo, Japan; Department of Neurology (M.S., H.M.), Department of Health Development and Medicine (M.S., H.K., H.N.), and Department of Clinical Gene Therapy (R.M.), Graduate School of Medicine, Osaka University, Japan; and Department of Human Genetics and Disease Diversity (R.W.) and Department of Cardiovascular Medicine
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14
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Stern JE, Son S, Biancardi VC, Zheng H, Sharma N, Patel KP. Astrocytes Contribute to Angiotensin II Stimulation of Hypothalamic Neuronal Activity and Sympathetic Outflow. Hypertension 2016; 68:1483-1493. [PMID: 27698069 DOI: 10.1161/hypertensionaha.116.07747] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 05/17/2016] [Accepted: 08/24/2016] [Indexed: 02/07/2023]
Abstract
Angiotensin II (AngII) is a key neuropeptide that acting within the brain hypothalamic paraventricular nucleus regulates neurohumoral outflow to the circulation. Moreover, an exacerbated AngII action within the paraventricular nucleus contributes to neurohumoral activation in hypertension. Although AngII effects involve changes in paraventricular nucleus neuronal activity, the precise underlying mechanisms, cellular targets, and distribution of AngII receptors within the paraventricular nucleus remain largely unknown. Thus, whether AngII effects involve direct actions on paraventricular neurons, or whether it acts via intermediary cells, such as astrocytes, is still controversial. To address this important gap in our knowledge, we used a multidisciplinary approach combining patch-clamp electrophysiology in presympathetic paraventricular neurons and astrocytes, along with in vivo sympathetic nerve recordings and astrocyte-targeted gene manipulations. We present evidence for a novel mechanism underlying central AngII actions, which involves astrocytes as major intermediary cellular targets. We found that AngII type 1 receptor mRNA is expressed in paraventricular astrocytes. Moreover, we report that AngII inhibited glutamate transporter function, increasing in turn extracellular glutamate levels. This resulted in the activation of neuronal extrasynaptic NMDA (N-methyl-d-aspartate) receptors, increased presympathetic neuronal activity, enhanced sympathoexcitatory outflow, and increased blood pressure. Together, our studies support astrocytes as critical intermediary cell types mediating brain AngII regulation of the circulation and indicate that AngII-mediated neuronal and sympathoexcitatory effects are dependent on a unique neuroglial signaling modality involving nonsynaptic glutamate transmission.
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Affiliation(s)
- Javier E Stern
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.).
| | - Sookjin Son
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.)
| | - Vinicia C Biancardi
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.)
| | - Hong Zheng
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.)
| | - Neeru Sharma
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.)
| | - Kaushik P Patel
- From the Department of Physiology, Augusta University, GA (J.E.S., S.S., V.C.B.); and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (H.Z., N.S., K.P.P.)
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15
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Labandeira-Garcia JL, Rodriguez-Perez AI, Valenzuela R, Costa-Besada MA, Guerra MJ. Menopause and Parkinson's disease. Interaction between estrogens and brain renin-angiotensin system in dopaminergic degeneration. Front Neuroendocrinol 2016; 43:44-59. [PMID: 27693730 DOI: 10.1016/j.yfrne.2016.09.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 09/26/2016] [Accepted: 09/27/2016] [Indexed: 02/07/2023]
Abstract
The neuroprotective effects of menopausal hormonal therapy in Parkinson's disease (PD) have not yet been clarified, and it is controversial whether there is a critical period for neuroprotection. Studies in animal models and clinical and epidemiological studies indicate that estrogens induce dopaminergic neuroprotection. Recent studies suggest that inhibition of the brain renin-angiotensin system (RAS) mediates the effects of estrogens in PD models. In the substantia nigra, ovariectomy induces a decrease in levels of estrogen receptor-α (ER-α) and increases angiotensin activity, NADPH-oxidase activity and expression of neuroinflammatory markers, which are regulated by estrogen replacement therapy. There is a critical period for the neuroprotective effect of estrogen replacement therapy, and local ER-α and RAS play a major role. Astrocytes play a major role in ER-α-induced regulation of local RAS, but neurons and microglia are also involved. Interestingly, treatment with angiotensin receptor antagonists after the critical period induced neuroprotection.
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Affiliation(s)
- Jose L Labandeira-Garcia
- Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain.
| | - Ana I Rodriguez-Perez
- Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Rita Valenzuela
- Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Maria A Costa-Besada
- Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Maria J Guerra
- Laboratory of Neuroanatomy and Experimental Neurology, Dept. of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
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16
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Gowrisankar YV, Clark MA. Regulation of angiotensinogen expression by angiotensin II in spontaneously hypertensive rat primary astrocyte cultures. Brain Res 2016; 1643:51-8. [DOI: 10.1016/j.brainres.2016.04.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 04/07/2016] [Accepted: 04/25/2016] [Indexed: 01/26/2023]
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17
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de Kloet AD, Liu M, Rodríguez V, Krause EG, Sumners C. Role of neurons and glia in the CNS actions of the renin-angiotensin system in cardiovascular control. Am J Physiol Regul Integr Comp Physiol 2015; 309:R444-58. [PMID: 26084692 DOI: 10.1152/ajpregu.00078.2015] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 06/15/2015] [Indexed: 02/07/2023]
Abstract
Despite tremendous research efforts, hypertension remains an epidemic health concern, leading often to the development of cardiovascular disease. It is well established that in many instances, the brain plays an important role in the onset and progression of hypertension via activation of the sympathetic nervous system. Further, the activity of the renin-angiotensin system (RAS) and of glial cell-mediated proinflammatory processes have independently been linked to this neural control and are, as a consequence, both attractive targets for the development of antihypertensive therapeutics. Although it is clear that the predominant effector peptide of the RAS, ANG II, activates its type-1 receptor on neurons to mediate some of its hypertensive actions, additional nuances of this brain RAS control of blood pressure are constantly being uncovered. One of these complexities is that the RAS is now thought to impact cardiovascular control, in part, via facilitating a glial cell-dependent proinflammatory milieu within cardiovascular control centers. Another complexity is that the newly characterized antihypertensive limbs of the RAS are now recognized to, in many cases, antagonize the prohypertensive ANG II type 1 receptor (AT1R)-mediated effects. That being said, the mechanism by which the RAS, glia, and neurons interact to regulate blood pressure is an active area of ongoing research. Here, we review the current understanding of these interactions and present a hypothetical model of how these exchanges may ultimately regulate cardiovascular function.
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Affiliation(s)
- Annette D de Kloet
- Department of Physiology and Functional Genomics, and McKnight Brain Institute, University of Florida College of Medicine, Gainesville, Florida; and
| | - Meng Liu
- Department of Physiology and Functional Genomics, and McKnight Brain Institute, University of Florida College of Medicine, Gainesville, Florida; and
| | - Vermalí Rodríguez
- Department of Physiology and Functional Genomics, and McKnight Brain Institute, University of Florida College of Medicine, Gainesville, Florida; and
| | - Eric G Krause
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Colin Sumners
- Department of Physiology and Functional Genomics, and McKnight Brain Institute, University of Florida College of Medicine, Gainesville, Florida; and
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18
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Isegawa K, Hirooka Y, Katsuki M, Kishi T, Sunagawa K. Angiotensin II type 1 receptor expression in astrocytes is upregulated leading to increased mortality in mice with myocardial infarction-induced heart failure. Am J Physiol Heart Circ Physiol 2014; 307:H1448-55. [DOI: 10.1152/ajpheart.00462.2014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Enhanced central sympathetic outflow worsens left ventricular (LV) remodeling and prognosis in heart failure after myocardial infarction (MI). Previous studies suggested that activation of brain angiotensin II type 1 receptors (AT1R) in the brain stem leads to sympathoexcitation due to neuronal AT1R upregulation. Recent studies, however, revealed the importance of astrocytes for modulating neuronal activity, but whether changes in astrocytes influence central sympathetic outflow in heart failure is unknown. In the normal state, AT1R are only weakly expressed in astrocytes. We hypothesized that AT1R in astrocytes are upregulated in heart failure and modulate the activity of adjacent neurons, leading to enhanced sympathetic outflow. In the present study, by targeting deletion of astrocyte-specific AT1R, we investigated whether AT1R in astrocytes have a key role in enhancing central sympathetic outflow, and thereby influencing LV remodeling process and the prognosis of MI-induced heart failure. Using the Cre-LoxP system, we generated glial fibrillary acidic protein (GFAP)-specific AT1R knockout (GFAP/AT1RKO) mice. Urinary norepinephrine excretion for 24 h, as an indicator of sympathoexcitation, was significantly lower in GFAP/AT1RKO-MI mice than in control-MI mice. LV size and heart weight after MI were significantly smaller in GFAP/AT1RKO mice than in control mice. Prognosis was significantly improved in GFAP/AT1RKO-MI mice compared with control-MI mice. Our findings indicated that AT1R expression was upregulated in brain stem astrocytes in MI-induced heart failure, which worsened LV remodeling and prognosis via sympathoexcitation. Thus, in addition to neuronal AT1R, AT1R in astrocytes appear to have a key role in enhancing central sympathetic outflow in heart failure.
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Affiliation(s)
- Kengo Isegawa
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Yoshitaka Hirooka
- Department of Advanced Cardiovascular Regulation and Therapeutics, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan; and
| | - Masato Katsuki
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Takuya Kishi
- Department of Advanced Therapeutics for Cardiovascular Diseases, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Kenji Sunagawa
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
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19
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Rodriguez-Perez AI, Borrajo A, Valenzuela R, Lanciego JL, Labandeira-Garcia JL. Critical period for dopaminergic neuroprotection by hormonal replacement in menopausal rats. Neurobiol Aging 2014; 36:1194-208. [PMID: 25432430 DOI: 10.1016/j.neurobiolaging.2014.10.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 10/01/2014] [Accepted: 10/24/2014] [Indexed: 10/24/2022]
Abstract
The neuroprotective effects of menopausal hormonal therapy in Parkinson's disease have not yet been clarified, and it is not known whether there is a critical period. Estrogen induced significant protection against 6-hydroxydopamine-induced dopaminergic degeneration when administered immediately or 6 weeks, but not 20 weeks after ovariectomy. In the substantia nigra, ovariectomy induced a decrease in levels of estrogen receptor-α and increased angiotensin activity, NADPH-oxidase activity, and expression of neuroinflammatory markers, which were regulated by estrogen administered immediately or 6 weeks but not 20 weeks after ovariectomy. Interestingly, treatment with angiotensin receptor antagonists after the critical period induced a significant level of neuroprotection. In cultures, treatment with 1-methyl-4-phenylpyridinium induced an increase in astrocyte-derived angiotensinogen and dopaminergic neuron death, which were inhibited by estrogen receptor α agonists. In microglial cells, estrogen receptor β agonists inhibited the angiotensin-induced increase in inflammatory markers. The results suggest that there is a critical period for the neuroprotective effect of estrogen against dopaminergic cell death, and local estrogen receptor α and renin-angiotensin system play a major role.
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Affiliation(s)
- Ana I Rodriguez-Perez
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Ana Borrajo
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Rita Valenzuela
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Jose L Lanciego
- Neurosciences Division, CIMA, University of Navarra, Pamplona, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain
| | - Jose L Labandeira-Garcia
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; Networking Research Center on Neurodegenerative Diseases (CIBERNED), Spain.
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20
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Abstract
The effects of brain AngII (angiotensin II) depend on AT(1) receptor (AngII type 1 receptor) stimulation and include regulation of cerebrovascular flow, autonomic and hormonal systems, stress, innate immune response and behaviour. Excessive brain AT(1) receptor activity associates with hypertension and heart failure, brain ischaemia, abnormal stress responses, blood-brain barrier breakdown and inflammation. These are risk factors leading to neuronal injury, the incidence and progression of neurodegerative, mood and traumatic brain disorders, and cognitive decline. In rodents, ARBs (AT(1) receptor blockers) ameliorate stress-induced disorders, anxiety and depression, protect cerebral blood flow during stroke, decrease brain inflammation and amyloid-β neurotoxicity and reduce traumatic brain injury. Direct anti-inflammatory protective effects, demonstrated in cultured microglia, cerebrovascular endothelial cells, neurons and human circulating monocytes, may result not only in AT(1) receptor blockade, but also from PPARγ (peroxisome-proliferator-activated receptor γ) stimulation. Controlled clinical studies indicate that ARBs protect cognition after stroke and during aging, and cohort analyses reveal that these compounds significantly reduce the incidence and progression of Alzheimer's disease. ARBs are commonly used for the therapy of hypertension, diabetes and stroke, but have not been studied in the context of neurodegenerative, mood or traumatic brain disorders, conditions lacking effective therapy. These compounds are well-tolerated pleiotropic neuroprotective agents with additional beneficial cardiovascular and metabolic profiles, and their use in central nervous system disorders offers a novel therapeutic approach of immediate translational value. ARBs should be tested for the prevention and therapy of neurodegenerative disorders, in particular Alzheimer's disease, affective disorders, such as co-morbid cardiovascular disease and depression, and traumatic brain injury.
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Affiliation(s)
- Juan M Saavedra
- Section on Pharmacology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD 20892, USA.
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21
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Gonzalez AD, Wang G, Waters EM, Gonzales KL, Speth RC, Van Kempen TA, Marques-Lopes J, Young CN, Butler SD, Davisson RL, Iadecola C, Pickel VM, Pierce JP, Milner TA. Distribution of angiotensin type 1a receptor-containing cells in the brains of bacterial artificial chromosome transgenic mice. Neuroscience 2012; 226:489-509. [PMID: 22922351 DOI: 10.1016/j.neuroscience.2012.08.039] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 08/16/2012] [Accepted: 08/17/2012] [Indexed: 10/28/2022]
Abstract
In the central nervous system, angiotensin II (AngII) binds to angiotensin type 1 receptors (AT(1)Rs) to affect autonomic and endocrine functions as well as learning and memory. However, understanding the function of cells containing AT(1)Rs has been restricted by limited availability of specific antisera, difficulties discriminating AT(1)R-immunoreactive cells in many brain regions and, the identification of AT(1)R-containing neurons for physiological and molecular studies. Here, we demonstrate that an Agtr1a bacterial artificial chromosome (BAC) transgenic mouse line that expresses type A AT(1)Rs (AT1aRs) identified by enhanced green fluorescent protein (EGFP) overcomes these shortcomings. Throughout the brain, AT1aR-EGFP was detected in the nuclei and cytoplasm of cells, most of which were neurons. EGFP often extended into dendritic processes and could be identified either natively or with immunolabeling of GFP. The distribution of AT1aR-EGFP cells in brain closely corresponded to that reported for AngII binding and AT1aR protein and mRNA. In particular, AT1aR-EGFP cells were in autonomic regions (e.g., hypothalamic paraventricular nucleus, central nucleus of the amygdala, parabrachial nucleus, nuclei of the solitary tract and rostral ventrolateral medulla) and in regions involved in electrolyte and fluid balance (i.e., subfornical organ) and learning and memory (i.e., cerebral cortex and hippocampus). Additionally, dual label electron microscopic studies in select brain areas demonstrate that cells containing AT1aR-EGFP colocalize with AT(1)R-immunoreactivity. Assessment of AngII-induced free radical production in isolated EGFP cells demonstrated feasibility of studies investigating AT1aR signaling ex vivo. These findings support the utility of Agtr1a BAC transgenic reporter mice for future studies understanding the role of AT(1)R-containing cells in brain function.
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Affiliation(s)
- A D Gonzalez
- Division of Neurobiology, Department of Neurology and Neuroscience, Weill Cornell Medical College, 407 East 61st Street, New York, NY 10065, USA
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22
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Current world literature. Curr Opin Nephrol Hypertens 2012; 21:557-66. [PMID: 22874470 DOI: 10.1097/mnh.0b013e3283574c3b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Involvement of the skeletal renin-angiotensin system in age-related osteoporosis of ageing mice. Biosci Biotechnol Biochem 2012; 76:1367-71. [PMID: 22785482 DOI: 10.1271/bbb.120123] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The local tissue-specific renin-angiotensin system (RAS) was identified. The aim of this study was to investigate the role of local bone RAS in the osteoporosis of aging mice. Twelve-month-old and two-month-old male mice were respectively assigned to the ageing and young groups. The tibias and femurs were collected for an analysis of histomorphology, bone mass, and gene and protein expression. H&E staining and micro-CT measurement showed a loss of the trabecular bone network and decrease of bone mineral density in the proximal tibial metaphysis of the aged mice. The PCR results indicated the significant up-regulation of renin and angiotensinogen (AGT) mRNA expression in both the tibia and femur of the ageing mice. Western blotting data showed that the tibial angiotensin II protein expression was significantly increased in the ageing group. The enhancement of renin and AGT expression in the bone tissue resulted in the increased production of angiotensin II which plays an important role in the pathology of age-related osteoporosis.
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