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Liu C, Yu H, Xia H, Wang Z, Li B, Xue H, Jin S, Xiao L, Wu Y, Guo Q. Butyrate attenuates sympathetic activation in rats with chronic heart failure by inhibiting microglial inflammation in the paraventricular nucleus. Acta Biochim Biophys Sin (Shanghai) 2024. [PMID: 38863438 DOI: 10.3724/abbs.2024092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024] Open
Abstract
Sympathetic activation is a hallmark of heart failure and the underlying mechanism remains elusive. Butyrate is generated by gut microbiota and influences numerous physiological and pathological processes in the host. The present study aims to investigate whether the intestinal metabolite butyrate reduces sympathetic activation in rats with heart failure (HF) and the underlying mechanisms involved. Sprague-Dawley rats (220‒250 g) are anaesthetized with isoflurane, and the left anterior descending artery is ligated to model HF. Then, the rats are treated with or without butyrate sodium (NaB, a donor of butyrate, 10 g/L in water) for 8 weeks. Blood pressure and renal sympathetic nerve activity (RSNA) are recorded to assess sympathetic outflow. Cardiac function is improved (mean ejection fraction, 22.6%±4.8% vs 38.3%±5.3%; P<0.05), and sympathetic activation is decreased (RSNA, 36.3%±7.9% vs 23.9%±7.6%; P<0.05) in HF rats treated with NaB compared with untreated HF rats. The plasma and cerebrospinal fluid levels of norepinephrine are decreased in HF rats treated with NaB. The infusion of N-methyl-D-aspartic acid (NMDA) into the paraventricular nucleus (PVN) of the hypothalamus of HF model rats increases sympathetic nervous activity by upregulating the NMDA receptor. Microglia polarized to the M2 phenotype and inflammation are markedly attenuated in the PVN of HF model rats after NaB administration. In addition, HF model rats treated with NaB exhibit enhanced intestinal barrier function and increased levels of GPR109A, zona occludens-1 and occludin, but decreased levels of lipopolysaccharide-binding protein and zonulin. In conclusion, butyrate attenuates sympathetic activation and improves cardiac function in rats with HF. The improvements in intestinal barrier function, reductions in microglia-mediated inflammation and decreases in NMDA receptor 1 expression in the PVN are all due to the protective effects of NaB.
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Affiliation(s)
- Chang Liu
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Hao Yu
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Hongyi Xia
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Ziwei Wang
- Department of Reproduction, the Second Hospital of Hebei Medical University, Shijiazhuang 050017, China
| | - Bolin Li
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Hongmei Xue
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Sheng Jin
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Lin Xiao
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
| | - Yuming Wu
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
- Hebei Collaborative Innovation Center for Cardio-Cerebrovascular Disease, Shijiazhuang 050017, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang 050017, China
- Hebei Key Laboratory of Cardiovascular Homeostasis and Aging, Shijiazhuang 050017, China
| | - Qi Guo
- Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China
- Experimental Center for Teaching, Hebei Medical University, Shijiazhuang 050017, China
- Hebei Key Laboratory of Cardiovascular Homeostasis and Aging, Shijiazhuang 050017, China
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AlShanableh Z, Ray EC. Magnesium in hypertension: mechanisms and clinical implications. Front Physiol 2024; 15:1363975. [PMID: 38665599 PMCID: PMC11044701 DOI: 10.3389/fphys.2024.1363975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
Hypertension is associated with increased risk of cardiovascular disease and death. Evidence suggests that Mg2+ depletion contributes to hypertension. It is estimated that 25% or more of the United States population experiences chronic, latent Mg2+ depletion. This review explores mechanisms by which Mg2+ influences blood pressure, modifying risk of hypertension and complicating its treatment. Mechanisms addressed include effects upon i) sympathetic tone, via the modulation of N-methyl-D-aspartate (NMDA) receptor and N-type Ca2+ channel activity, influencing catecholamine release from sympathetic nerve endings; ii) vascular tone, via alteration of L-type Ca2+ and endothelial nitric oxide synthase (eNOS) activity and prostacyclin release; iii) renal K+ handling, influencing systemic K+ balance and potentially indirectly influencing blood pressure; iv) aldosterone secretion from the adrenal cortex; and v) modulation of pro-hypertensive inflammatory processes in dendritic cells and macrophages, including activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome and stimulation of isolevuglandin (IsoLG) production. Discovery of these mechanisms has furthered our understanding of the pathogenesis of hypertension, with implications for treatment and has highlighted the role of Mg2+ balance in hypertension and cardiovascular disease.
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Affiliation(s)
| | - Evan C. Ray
- Renal-Electrolyte Division, UPMC and University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Yamaguchi J, Andrade MA, Truong TT, Toney GM. Glutamate Spillover Dynamically Strengthens Gabaergic Synaptic Inhibition of the Hypothalamic Paraventricular Nucleus. J Neurosci 2024; 44:e1851222023. [PMID: 38154957 PMCID: PMC10869154 DOI: 10.1523/jneurosci.1851-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/16/2023] [Accepted: 12/20/2023] [Indexed: 12/30/2023] Open
Abstract
The hypothalamic paraventricular nucleus (PVN) is strongly inhibited by γ-aminobutyric acid (GABA) from the surrounding peri-nuclear zone (PNZ). Because glutamate mediates fast excitatory transmission and is substrate for GABA synthesis, we tested its capacity to dynamically strengthen GABA inhibition. In PVN slices from male mice, bath glutamate applied during ionotropic glutamate receptor blockade increased PNZ-evoked inhibitory postsynaptic currents (eIPSCs) without affecting GABA-A receptor agonist currents or single-channel conductance, implicating a presynaptic mechanism(s). Consistent with this interpretation, bath glutamate failed to strengthen IPSCs during pharmacological saturation of GABA-A receptors. Presynaptic analyses revealed that glutamate did not affect paired-pulse ratio, peak eIPSC variability, GABA vesicle recycling speed, or readily releasable pool (RRP) size. Notably, glutamate-GABA strengthening (GGS) was unaffected by metabotropic glutamate receptor blockade and graded external Ca2+ when normalized to baseline amplitude. GGS was prevented by pan- but not glial-specific inhibition of glutamate uptake and by inhibition of glutamic acid decarboxylase (GAD), indicating reliance on glutamate uptake by neuronal excitatory amino acid transporter 3 (EAAT3) and enzymatic conversion of glutamate to GABA. EAAT3 immunoreactivity was strongly localized to presumptive PVN GABA terminals. High bath K+ also induced GGS, which was prevented by glutamate vesicle depletion, indicating that synaptic glutamate release strengthens PVN GABA inhibition. GGS suppressed PVN cell firing, indicating its functional significance. In sum, PVN GGS buffers neuronal excitation by apparent "over-filling" of vesicles with GABA synthesized from synaptically released glutamate. We posit that GGS protects against sustained PVN excitation and excitotoxicity while potentially aiding stress adaptation and habituation.
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Affiliation(s)
- Junya Yamaguchi
- Department of Cellular & Integrative Physiology, University of Texas Health San Antonio, San Antonio 78229-3900, Texas
| | - Mary Ann Andrade
- Department of Cellular & Integrative Physiology, University of Texas Health San Antonio, San Antonio 78229-3900, Texas
| | - Tamara T Truong
- Department of Cellular & Integrative Physiology, University of Texas Health San Antonio, San Antonio 78229-3900, Texas
| | - Glenn M Toney
- Department of Cellular & Integrative Physiology, University of Texas Health San Antonio, San Antonio 78229-3900, Texas
- Center for Biomedical Neuroscience, University of Texas Health San Antonio, San Antonio 78229-3900, Texas
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Zahner MR, Brown MC, Chandley MJ. Inactivation of the paraventricular nucleus attenuates the cardiogenic sympathetic afferent reflex in the spontaneously hypertensive rat. J Hypertens 2024; 42:70-78. [PMID: 37889604 PMCID: PMC10792548 DOI: 10.1097/hjh.0000000000003542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/29/2023]
Abstract
BACKGROUND Myocardial ischemia causes the release of bradykinin, which stimulates cardiac afferents, causing sympathetic excitation and chest pain. Glutamatergic activation of the paraventricular hypothalamic nucleus (PVN) in the spontaneously hypertensive rat (SHR) drives elevated basal sympathetic activity. Thus, we tested the hypothesis that inactivation of the PVN attenuates the elevated reflex response to epicardial bradykinin in the SHR and that ionotropic PVN glutamate receptors mediate the elevated reflex. METHODS We recorded the arterial pressure and renal sympathetic nerve activity (RSNA) response to epicardial bradykinin application in anesthetized SHR and Wistar Kyoto (WKY) rats before and after PVN microinjection of GABA A agonist muscimol or ionotropic glutamate receptor antagonist kynurenic acid. RESULTS Muscimol significantly decreased the arterial pressure response to bradykinin from 180.4 ± 5.8 to 119.5 ± 6.9 mmHg in the SHR and from 111.8 ± 7.0 to 84.2 ± 8.3 mmHg in the WKY and the RSNA response from 186.2 ± 7.1 to 142.7 ± 7.3% of baseline in the SHR and from 201.0 ± 11.5 to 160.2 ± 9.3% of baseline in the WKY. Kynurenic acid significantly decreased the arterial pressure response in the SHR from 164.5 ± 5.0 to 126.2 ± 7.7 mmHg and the RSNA response from 189.9 ± 13.7to 168.5 ± 12.7% of baseline but had no effect in the WKY. CONCLUSION These results suggest that tonic PVN activity is critical for the full manifestation of the CSAR in both the WKY and SHR. Glutamatergic PVN activity contributes to the augmented CSAR observed in the SHR.
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Affiliation(s)
- Matthew R Zahner
- Department of Health Sciences, East Tennessee State University College of Public Health
| | - Mary C Brown
- Department of Health Sciences, East Tennessee State University College of Public Health
| | - Michelle J Chandley
- Department of Biomedical Science, East Tennessee State University College of Medicine, Johnson City, Tennessee, USA
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Xi H, Li X, Zhou Y, Sun Y. The Regulatory Effect of the Paraventricular Nucleus on Hypertension. Neuroendocrinology 2023; 114:1-13. [PMID: 37598678 DOI: 10.1159/000533691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 08/17/2023] [Indexed: 08/22/2023]
Abstract
Hypertension is among the most harmful factors of cardiovascular and cerebrovascular diseases and poses an urgent problem for the development of human society. In addition to previous studies on its pathogenesis focusing on the peripheral sympathetic nervous system, investigating the central causes of high blood pressure involving the neuroendocrine and neuroinflammatory mechanisms of the hypothalamic paraventricular nucleus (PVN) is paramount. This nucleus is considered to regulate the output of neurohormones and sympathetic nerve activity. In this article, we focussed on the neuroendocrine mechanism, primarily exploring the specific contributions and interactions of various neurons and neuroendocrine hormones, including GABAergic and glutamatergic neurons, nitric oxide, arginine vasopressin, oxytocin, and the renin-angiotensin system. Additionally, the neuroinflammatory mechanism in the PVN was discussed, encompassing microglia, reactive oxygen species, inflammatory factors, and pathways, as well as immune connections between the brain and extracerebral organs. Notably, the two central mechanisms involved in the PVN not only exist independently but also communicate with each other, jointly maintaining the hypertensive state of the body. Furthermore, we introduce well-known molecules and signal transduction pathways within the PVN that can play a regulatory role in the two mechanisms to provide a basis and inspire ideas for further research.
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Affiliation(s)
- Hanyu Xi
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
| | - Xingru Li
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
| | - Yun Zhou
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
- Department of Nephrology, Shanxi Provincial Integrated Traditional Chinese Medicine and Western Medicine Hospital, Taiyuan, China
| | - Yaojun Sun
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, China
- School of Basic Medicine, Shanxi Medical University, Taiyuan, China
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Fan JF, Wang W, Tan X, Ye P, Li JK, Niu LY, Li WY, Wang WZ, Wang YK. Contribution of cyclooxygenase-2 overexpression to enhancement in tonically active glutamatergic inputs to the rostral ventrolateral medulla in hypertension. J Hypertens 2022; 40:2394-2405. [PMID: 36189462 DOI: 10.1097/hjh.0000000000003268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
OBJECTIVE Cyclooxygenase (COX) is critical in regulating cardiovascular function, but its role involved in the central control of blood pressure (BP) is uncovered. The tonic glutamatergic inputs to the rostral ventrolateral medulla (RVLM) are enhanced in hypertension. Here, the present study was designed to investigate the effect and mechanism of central COX on tonic glutamatergic inputs to the RVLM and BP regulation. METHODS Wistar-Kyoto (WKY) rats and spontaneous hypertensive rats (SHRs) received RVLM microinjection of adeno-associated viral vectors to promote or inhibit the COX2 expression were subjected to subsequent experiments. Glutamate level and glutaminase expression were detected by ELISA and western blot, respectively. The function of tonic glutamatergic inputs was assessed by BP response to microinjection of the glutamate receptor antagonist into the RVLM. PC12 cells were used to detect the underlying signal pathway. RESULTS The RVLM COX2 expression and prostaglandin E2 level were significant higher in SHRs than in WKY rats. Overexpression of COX2 in the RVLM produced an increase in basal BP, RVLM glutamate level, and glutaminase expression in WKY rats, while they were significantly reduced by interfering with COX2 expression in SHRs. Microinjections of the glutamate receptor antagonist into the RVLM produced a significant BP decrease in WKY rats with COX2 overexpression pretreatment. Furthermore, the increased levels of BP, glutamate content, and glutaminase activity in the RVLM evoked by central infusion of angiotensin II were attenuated in COX2 knockout mice. It was also found that prostaglandin E2 increased supernatant glutamate level and phosphorylation of signal transducer and activator of transcription 3 in PC12 cells. CONCLUSION Our findings suggest that upregulated COX2 expression enhances the tonically active glutamatergic inputs to the RVLM, which is associated with cardiovascular regulation in hypertension.
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Affiliation(s)
- Jie-Fu Fan
- Department of Marine Biomedicine and Polar Medicine, Naval Medical University (Second Military Medical University), Shanghai, China
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Zhu X, Li K, Gao Y. Adeno-associated virus-mediated in vivo suppression of expression of EPHX2 gene modulates the activity of paraventricular nucleus neurons in spontaneously hypertensive rats. Biochem Biophys Res Commun 2022; 606:121-127. [PMID: 35344709 DOI: 10.1016/j.bbrc.2022.03.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 03/16/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Hypertension can be attributed to increased sympathetic activities. Presympathetic neurons in the paraventricular nucleus (PVN) of the hypothalamus are capable of modulating sympathetic outflow, thus contributing to the pathogenesis of neurogenic hypertension. Epoxyeicosatrienoic acids (EETs) were reported to have anti-hypertensive effects, which could be degraded by soluble epoxide hydrolase (sEH), encoded by EPHX2. However, the potential effect of EETs on PVN neuron activity and the underlying molecular mechanism are largely unknown. METHODS Knockdown of EPHX2 in spontaneously hypertensive rats (SHRs) was achieved by tail-intravenous injection of AAV plasmid containing shRNA targeting EPHX2. Whole-cell patch clamp was used to record action potentials of PVN neurons. An LC-MS/MS System was employed to determine 14,15-EET levels in rat cerebrospinal fluid. qPCR and western blotting were applied to examine the expression level of EPHX2 in various tissues. ELISA and immunofluorescence staining were applied to examine the levels of ATP, D-serine and glial fibrillary acidic protein (GFAP) in isolated astrocytes. RESULTS The expression level of EPHX2 was higher, while the level of 14,15-EET was lower in SHRs than normotensive Wistar-Kyoto rats (WKY) rats. The spike firing frequency of PNV neurons in SHRs was higher than in WKY rats at a given stimulus current, which could be reduced by either EPHX2 downregulation or 14,15-EET administration. In isolated hypothalamic astrocytes, the elevated intracellular ATP or D-serine induced by Angiotensin II (Ang II) treatment could be rescued by 14,15-EET addition or 14,15-EET combing serine racemase (SR) downregulation by siRNA, respectively. Furthermore, 14,15-EET treatment reduced the Ang II-induced elevation of GFAP immunofluorescence. CONCLUSIONS The elevation of EET levels by EPHX2 downregulation reduced presympathetic neuronal activity in the PVN of SHRs, leading to a reduced sympathetic outflow in hypertension rats. The ATP/SR/D-serine pathway of astrocytes is involved in EET-mediated neuroprotection.
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Affiliation(s)
- Xiaoming Zhu
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Kuibao Li
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Yuanfeng Gao
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
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Wang G, Woods C, Johnson MA, Milner TA, Glass MJ. Angiotensin II Infusion Results in Both Hypertension and Increased AMPA GluA1 Signaling in Hypothalamic Paraventricular Nucleus of Male but not Female Mice. Neuroscience 2022; 485:129-144. [PMID: 34999197 PMCID: PMC9116447 DOI: 10.1016/j.neuroscience.2021.12.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 10/19/2022]
Abstract
The hypothalamic paraventricular nucleus (PVN) plays a key role in hypertension, however the signaling pathways that contribute to the adaptability of the PVN during hypertension are uncertain. We present evidence that signaling at the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) GluA1 receptor contributes to increased blood pressure in a model of neurogenic hypertension induced by 14-day slow-pressor angiotensin II (AngII) infusion in male mice. It was found that AngII hypertension was associated with an increase in plasma membrane affiliation of GluA1, but decreased GluA2, in dendritic profiles of PVN neurons expressing the TNFα type 1 receptor, a modulator of AMPA receptor trafficking. The increased plasma membrane GluA1 was paralleled by heightened AMPA currents in PVN-spinal cord projection neurons from AngII-infused male mice. Significantly, elevated AMPA currents in AngII-treated mice were blocked by 1-Naphthyl acetyl spermine trihydrochloride, pointing to the involvement of GluA2-lacking GluA1 receptors in the heightened AMPA signaling in PVN neurons. A further functional role for GluA1 in the PVN was demonstrated by the attenuated hypertensive response following silencing of GluA1 in the PVN of AngII-infused male mice. In female mice, AngII-infusion did not impact blood pressure or plasma membrane localization of GluA1 . Post-translational modifications that increase the plasma membrane localization of AMPA GluA1 and heighten the rapid excitatory signaling actions of glutamate in PVN neurons may serve as a molecular substrate underlying sex differences in hypertension.
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Affiliation(s)
- Gang Wang
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Clara Woods
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Megan A. Johnson
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065
| | - Teresa A. Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065,Harold and Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY 10065
| | - Michael J. Glass
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065,Address correspondence to: Dr. Michael J. Glass, Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065; Phone: (646) 962-8253;
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Involvement of Neuropeptide Y within Paraventricular Nucleus in Electroacupuncture Inhibiting Sympathetic Activities in Hypertensive Rats. Int J Hypertens 2022; 2022:9990854. [PMID: 35087687 PMCID: PMC8789434 DOI: 10.1155/2022/9990854] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/05/2022] [Indexed: 12/14/2022] Open
Abstract
Although electroacupuncture (EA) has been used to decrease the blood pressure (BP) clinically, the underlying mechanisms are not clearly clarified. This study aimed to assess the hypothesis that EA treatment exerts a hypotensive action via suppressing sympathetic activities and modulating neuropeptide Y (NPY) function within the paraventricular nucleus (PVN) of hypertensive rats. Male Sprague-Dawley rats were selected for the experiment, and the hypertensive models were established by the two-kidney, one-clip (2K1C) method. Then, the rats were randomly assigned to the sham group, 2K1C group, 2K1C plus EA group, and 2K1C plus sham EA group. EA treatment at the acupoints ST36 and ST40 overlying the peroneal nerves was given once a day for 30 days. The radiotelemetry system was applied to collect the arterial BP recordings. Power spectral analyses of BP variability, BP responses to ganglionic blockade, and plasma levels of norepinephrine and epinephrine were performed to assess the changes in sympathetic nerve activity. Real-time PCR and Western blots were carried out to examine the expression of NPY system in the PVN. The responses of PVN microinjection with NPY Y1R antagonist BIBO3304 were detected to check the endogenous NPY tone. The results showed that the enhanced arterial BP and sympathetic activities were effectively reduced by 30 days of EA treatment, and baroreflex sensitivity was improved in 2K1C hypertensive rats. The level of NPY mRNA and protein expression in the PVN was markedly upregulated by EA treatment in 2K1C rats. In addition, the pressor responses of PVN microinjection with NPY Y1R antagonist BIBO3304 in 2K1C models were remarkably augmented by the EA stimulation. Our results indicate that the increased NPY expression and function in the PVN induced by EA treatment contribute to antihypertensive and sympathetic suppression on hypertensive rats. The findings may elucidate the underlying mechanisms of the acupuncture to be a potential therapeutic strategy against hypertension.
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Pittman QJ. Vasopressin and central control of the cardiovascular system: A 40-year retrospective. J Neuroendocrinol 2021; 33:e13011. [PMID: 34235812 DOI: 10.1111/jne.13011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 06/25/2021] [Indexed: 01/24/2023]
Abstract
In the 40 years since vasopressin (AVP) was reported to have a central action with respect to raising blood pressure, the finding has been repeatedly replicated using a variety of complimentary approaches. The role of AVP as a central neurotransmitter involved in control of the cardiovascular system is now textbook material. However, it is evident that brain AVP plays, at best, a minor role in regulation of normal blood pressure. However, it appears to be an important player in a several cardiovascular-associated pathologies, ranging from hypertension to neural changes associated with heart failure. There are many interventions that have been shown to affect neural function, many of which are associated with alterations in behaviour. Possible alterations in neuronal AVP actions relevant to cardiovascular control in the setting of chronic inflammatory disease, early-life stress and inflammation are suggested areas for future research.
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Affiliation(s)
- Quentin J Pittman
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
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Kassan A, Ait-Aissa K, Kassan M. Hypothalamic miR-204 Induces Alteration of Heart Electrophysiology and Neurogenic Hypertension by Regulating the Sympathetic Nerve Activity: Potential Role of Microbiota. Cureus 2021; 13:e18783. [PMID: 34692262 PMCID: PMC8523185 DOI: 10.7759/cureus.18783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2021] [Indexed: 02/06/2023] Open
Abstract
There is abundant evidence demonstrating the association between gut dysbiosis and neurogenic diseases such as hypertension. A common characteristic of resistant hypertension is the chronic elevation in sympathetic nervous system (SNS) activity accompanied by increased release of norepinephrine (NE), indicating a neurogenic component that contributes to the development of hypertension. Factors that modulate the sympathetic tone to the cardiovascular system in hypertensive patients are still poorly understood. Research has identified an interaction between the brain and the gut, and this interaction plays a possible role in the mechanism of heart damage-induced hypertension. Data, however, remain scarce, and further study is required to define the role of microbiota in sympathetic neural function and its relationship with heart damage and blood pressure (BP) control. Experimental evidence has pointed toward a bidirectional relationship between alterations in the types of bacteria present in the gut and neurogenic diseases, such as hypertension. Our published data showed that miR-204, a microRNA that plays an important role in the CNS function, is affected by gut dysbiosis. Therefore, miR-204 could be a key element that regulates normal sinus rhythm and neuronal hypertension. In this review, we will shed light on the potential mechanism by which microbiota affects hypothalamic miR-204, which in turn, could hinder the sympathetic nerve drive to the cardiovascular system leading to arrhythmia and hypertension.
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Affiliation(s)
- Adam Kassan
- School of Pharmacy, West Coast University, Los Angeles, USA
| | | | - Modar Kassan
- Physiology, The University of Tennessee Health Science Center, Memphis, USA
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Li Y, Lu YX, Chi HL, Xiao T, Chen YM, Fu LY, Zibrila AI, Qi J, Li HB, Su Q, Gao HL, Zhang Y, Shi XL, Yu XJ, Kang YM. Chronic Blockade of NMDAR Subunit 2A in the Hypothalamic Paraventricular Nucleus Alleviates Hypertension Through Suppression of MEK/ERK/CREB Pathway. Am J Hypertens 2021; 34:840-850. [PMID: 33856436 DOI: 10.1093/ajh/hpab047] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 02/05/2021] [Accepted: 04/14/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND N-Methyl-d-aspartate receptor (NMDAR) in the hypothalamic paraventricular nucleus (PVN) plays critical roles in regulating sympathetic outflow. Studies showed that acute application of the antagonists of NMDAR or its subunits would reduce sympathetic nerve discharges. However, little is known about the effect of long-term management of NMDAR in hypertensive animals. METHODS PEAQX, the specific antagonist of NMDAR subunit 2A (GluN2A) was injected into both sides of the PVN of two-kidney, one-clip (2K1C) renal hypertensive rats and control (normotensive rats) for 3 weeks. RESULTS Three weeks of PEAQX infusion significantly reduced the blood pressure of the 2K1C rats. It managed to resume the balance between excitatory and inhibitory neural transmitters, reduce the level of proinflammatory cytokines and reactive oxygen species in the PVN, and reduce the level of norepinephrine in plasma of the 2K1C rats. PEAQX administration also largely reduced the transcription and translation levels of GluN2A and changed the expression levels of NMDAR subunits 1 and 2B (GluN1 and GluN2B). In addition, NMDAR was known to function through activating the extracellular regulated protein kinases (ERK) or phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways. In our study, we found that in the PVN of 2K1C rats treated with PEAQX, the phosphorylation levels of mitogen-activated protein kinase kinase (MEK), ERK1/2, and cAMP-response element-binding protein (CREB) significantly reduced, while the phosphorylation level of PI3K did not change significantly. CONCLUSIONS Chronic blockade of GluN2A alleviates hypertension through suppression of MEK/ERK/CREB pathway.
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Affiliation(s)
- Ying Li
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Yu-Xin Lu
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Hong-Li Chi
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Tong Xiao
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Yan-Mei Chen
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Li-Yan Fu
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Abdoulaye Issotina Zibrila
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Jie Qi
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Hong-Bao Li
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Qing Su
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Hong-Li Gao
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Yan Zhang
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Xiao-Lian Shi
- Department of Pharmacology, Xi’an Jiaotong University School of Basic Medical Sciences, Xi’an, China
| | - Xiao-Jing Yu
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
| | - Yu-Ming Kang
- Department of Physiology and Pathophysiology, Xi’an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi’an, China
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13
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Yen PSY, Liu YC, Chu CH, Chen SL. Upregulation of Glutamatergic Receptors in Hippocampus and Locomotor Hyperactivity in Aged Spontaneous Hypertensive Rat. Cell Mol Neurobiol 2021; 42:2205-2217. [PMID: 33954807 DOI: 10.1007/s10571-021-01094-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 04/19/2021] [Indexed: 10/21/2022]
Abstract
Epidemiologic studies have indicated that chronic hypertension may facilitate the progression of abnormal behavior, such as emotional irritability, hyperactivity, and attention impairment. However, the mechanism of how chronic hypertension affects the brain and neuronal function remains unclear. In this study, 58-week-old male spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) control rats were used. Their locomotor activity and neuronal function were assessed by the open field test, novel object, and Y maze recognition test. Moreover brain tissues were analyzed. We found that the aged SHR exhibited significant locomotor hyperactivity when compared to the WKY rats. However, there was no significant difference in novel object and novel arm recognition between aged SHR and the WKY rats. In the analysis of synaptic membrane protein, the expression of glutamatergic receptors, such as the N-methyl-D-aspartate (NMDA) receptor receptors subunits 2B (GluN2B) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor 1 (GluA1) in the hippocampus of SHR were significantly higher than those of WKY rats. In addition, in the synaptic membrane of SHR's hippocampus and medial prefrontal cortex (mPFC), a down-regulation of astrocytes was found, though the excitatory amino acid transporter 2 (EAAT2) remained constant. Moreover, a down-regulation of microglia in the hippocampus and mPFC was seen in the SHR brain. Long-term exposure to high blood pressure causes upregulation of glutamate receptors. The upregulation of glutamatergic receptors in hippocampus may contribute to the hyper-locomotor activity of aged rodents and may as a therapeutic target in hypertension-induced irritability and hyperactivity.
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Affiliation(s)
- Patrick Szu-Ying Yen
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University (KMU), Kaohsiung, Taiwan
| | - Yen-Chin Liu
- Department of Anesthesiology, College of Medicine, National Cheng Kung University Hospital (NCKU), NCKU, 100 Shiquan 1st Rd, Sanmin Dist., Kaohsiung City, 807, Taiwan
| | - Chun-Hsien Chu
- Institute of Molecular Medicine, College of Medicine, NCKU, Tainan, Taiwan
| | - Shiou-Lan Chen
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University (KMU), Kaohsiung, Taiwan. .,Department of Medical Research, College of Medicine, KMU Hospital & MSc Program in Tropical Medicine, KMU, Kaohsiung, Taiwan.
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14
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Underwood CF, Mcmullan S, Goodchild AK, Phillips JK, Hildreth CM. The subfornical organ drives hypertension in polycystic kidney disease via the hypothalamic paraventricular nucleus. Cardiovasc Res 2021; 118:1138-1149. [PMID: 33774660 DOI: 10.1093/cvr/cvab122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/25/2021] [Indexed: 11/14/2022] Open
Abstract
AIMS Hypertension is a prevalent yet poorly understood feature of polycystic kidney disease. Previously we demonstrated that increased glutamatergic neurotransmission within the hypothalamic paraventricular nucleus produces hypertension in the Lewis Polycystic Kidney rat model of polycystic kidney disease. Here we tested the hypothesis that augmented glutamatergic drive to the paraventricular nucleus in Lewis Polycystic Kidney rats originates from the forebrain lamina terminalis, a sensory structure that relays blood-borne information throughout the brain. METHODS AND RESULTS Anatomical experiments revealed that 38% of paraventricular nucleus-projecting neurons in the subfornical organ of the lamina terminalis expressed Fos/Fra, an activation marker, in Lewis Polycystic Kidney rats while <1% of neurons were Fos/Fra+ in Lewis control rats (P = 0.01, n = 8). In anaesthetised rats, subfornical organ neuronal inhibition using isoguvacine produced a greater reduction in systolic blood pressure in the Lewis Polycystic Kidney versus Lewis rats (-21 ± 4 vs. -7 ± 2 mmHg, P < 0.01; n = 10), which could be prevented by prior blockade of paraventricular nucleus ionotropic glutamate receptors using kynurenic acid. Blockade of ionotropic glutamate receptors in the paraventricular nucleus produced an exaggerated depressor response in Lewis Polycystic Kidney relative to Lewis rats (-23 ± 4 vs. -2 ± 3 mmHg, P < 0.001; n = 13), which was corrected by prior inhibition of the subfornical organ with muscimol but unaffected by chronic systemic angiotensin II type I receptor antagonism or lowering of plasma hyperosmolality through high-water intake (P > 0.05); treatments that both nevertheless lowered blood pressure in Lewis Polycystic Kidney rats (P < 0.0001). CONCLUSION Our data reveal multiple independent mechanisms contribute to hypertension in polycystic kidney disease, and identify high plasma osmolality, angiotensin II type I receptor activation and, importantly, a hyperactive subfornical organ to paraventricular nucleus glutamatergic pathway as potential therapeutic targets. TRANSLATIONAL PERSPECTIVE Hypertension is a significant comorbidity for all forms of chronic kidney disease and for individuals with polycystic kidney disease, often an early presenting feature. Nevertheless, the cause(s) of hypertension in polycystic kidney disease are poorly defined. Here we define the contribution of a neural pathway that contributes to hypertension in polycystic kidney disease. Critically, targeting this pathway may provide an additional antihypertensive effect beyond that achieved with current conventional antihypertensive therapies. Future work identifying the drivers of this neural pathway will aid in the development of newer generation antihypertensive medication.
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Affiliation(s)
- Conor F Underwood
- Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, AUSTRALIA.,Department of Anatomy, School of Biomedical Sciences, University of Otago, Otago, NEW ZEALAND
| | - Simon Mcmullan
- Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, AUSTRALIA
| | - Ann K Goodchild
- Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, AUSTRALIA
| | - Jacqueline K Phillips
- Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, AUSTRALIA
| | - Cara M Hildreth
- Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, AUSTRALIA
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15
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Woods C, Marques-Lopes J, Contoreggi NH, Milner TA, Pickel VM, Wang G, Glass MJ. Tumor Necrosis Factor α Receptor Type 1 Activation in the Hypothalamic Paraventricular Nucleus Contributes to Glutamate Signaling and Angiotensin II-Dependent Hypertension. J Neurosci 2021; 41:1349-1362. [PMID: 33303682 PMCID: PMC7888211 DOI: 10.1523/jneurosci.2360-19.2020] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/06/2020] [Accepted: 11/27/2020] [Indexed: 12/11/2022] Open
Abstract
There are significant neurogenic and inflammatory influences on blood pressure, yet the role played by each of these processes in the development of hypertension is unclear. Tumor necrosis factor α (TNFα) has emerged as a critical modulator of blood pressure and neural plasticity; however, the mechanism by which TNFα signaling contributes to the development of hypertension is uncertain. We present evidence that following angiotensin II (AngII) infusion the TNFα type 1 receptor (TNFR1) plays a key role in heightened glutamate signaling in the hypothalamic paraventricular nucleus (PVN), a key central coordinator of blood pressure control. Fourteen day administration of a slow-pressor dose of AngII in male mice was associated with transcriptional and post-transcriptional (increased plasma membrane affiliation) regulation of TNFR1 in the PVN. Further, TNFR1 was shown to be critical for elevated NMDA-mediated excitatory currents in sympathoexcitatory PVN neurons following AngII infusion. Finally, silencing PVN TNFR1 prevented the increase in systolic blood pressure induced by AngII. These findings indicate that TNFR1 modulates a cellular pathway involving an increase in NMDA-mediated currents in the PVN following AngII infusion, suggesting a mechanism whereby TNFR1 activation contributes to hypertension via heightened hypothalamic glutamate-dependent signaling.SIGNIFICANCE STATEMENT Inflammation is critical for the emergence of hypertension, yet the mechanisms by which inflammatory mediators contribute to this dysfunction are not clearly defined. We show that tumor necrosis factor α receptor 1 (TNFR1) in the paraventricular hypothalamic nucleus (PVN), a critical neuroregulator of cardiovascular function, plays an important role in the development of hypertension in mice. In the PVN, TNFR1 expression and plasma membrane localization are upregulated during hypertension induced by angiotensin II (AngII). Further, TNFR1 activation was essential for NMDA signaling and the heightening NMDA currents during hypertension. Finally, TNFR1 silencing in the PVN inhibits elevated blood pressure induced by AngII. These results point to a critical role for hypothalamic TNFR1 signaling in hypertension.
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Affiliation(s)
- Clara Woods
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
| | - Jose Marques-Lopes
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
| | - Natalina H Contoreggi
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
- Harold and Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York 10065
| | - Virginia M Pickel
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
| | - Gang Wang
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
| | - Michael J Glass
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
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16
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Contoreggi NH, Mazid S, Goldstein LB, Park J, Ovalles AC, Waters EM, Glass MJ, Milner TA. Sex and age influence gonadal steroid hormone receptor distributions relative to estrogen receptor β-containing neurons in the mouse hypothalamic paraventricular nucleus. J Comp Neurol 2021; 529:2283-2310. [PMID: 33341960 DOI: 10.1002/cne.25093] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 12/17/2022]
Abstract
Within the hypothalamic paraventricular nucleus (PVN), estrogen receptor (ER) β and other gonadal hormone receptors play a role in central cardiovascular processes. However, the influence of sex and age on the cellular and subcellular relationships of ERβ with ERα, G-protein ER (GPER1), as well as progestin and androgen receptors (PR and AR) in the PVN is uncertain. In young (2- to 3-month-old) females and males, ERβ-enhanced green fluorescent protein (EGFP) containing neurons were approximately four times greater than ERα-labeled and PR-labeled nuclei in the PVN. In subdivisions of the PVN, young females, compared to males, had: (1) more ERβ-EGFP neurons in neuroendocrine rostral regions; (2) fewer ERα-labeled nuclei in neuroendocrine and autonomic projecting medial subregions; and (3) more ERα-labeled nuclei in an autonomic projecting caudal region. In contrast, young males, compared to females, had approximately 20 times more AR-labeled nuclei, which often colocalized with ERβ-EGFP in neuroendocrine (approximately 70%) and autonomic (approximately 50%) projecting subregions. Ultrastructurally, in soma and dendrites, PVN ERβ-EGFP colocalized primarily with extranuclear AR (approximately 85% soma) and GPER1 (approximately 70% soma). Aged (12- to 24-month-old) males had more ERβ-EGFP neurons in a rostral neuroendocrine subregion compared to aged females and females with accelerated ovarian failure (AOF) and in a caudal autonomic subregion compared to post-AOF females. Late-aged (18- to 24-month-old) females compared to early-aged (12- to 14-month-old) females and AOF females had fewer AR-labeled nuclei in neuroendrocrine and autonomic projecting subregions. These findings indicate that gonadal steroids may directly and indirectly influence PVN neurons via nuclear and extranuclear gonadal hormone receptors in a sex-specific manner.
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Affiliation(s)
| | - Sanoara Mazid
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY
| | - Lily B Goldstein
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY
| | - John Park
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY
| | - Astrid C Ovalles
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY
| | - Elizabeth M Waters
- Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, NY
| | - Michael J Glass
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY.,Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, NY
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17
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Sharma NM, Haibara AS, Katsurada K, Nandi SS, Liu X, Zheng H, Patel KP. Central Ang II (Angiotensin II)-Mediated Sympathoexcitation: Role for HIF-1α (Hypoxia-Inducible Factor-1α) Facilitated Glutamatergic Tone in the Paraventricular Nucleus of the Hypothalamus. Hypertension 2020; 77:147-157. [PMID: 33296248 PMCID: PMC7720881 DOI: 10.1161/hypertensionaha.120.16002] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Central infusion of Ang II (angiotensin II) has been associated with increased sympathetic outflow resulting in neurogenic hypertension. In the present study, we appraised whether the chronic increase in central Ang II activates the paraventricular nucleus of the hypothalamus (PVN) resulting in elevated sympathetic tone and altered baro- and chemoreflexes. Further, we evaluated the contribution of HIF-1α (hypoxia-inducible factor-1α), a transcription factor involved in enhancing the expression of N-methyl-D-aspartate receptors and thus glutamatergic-mediated sympathetic tone from the PVN. Ang II infusion (20 ng/minute, intracerebroventricular, 14 days) increased mean arterial pressure (126±9 versus 84±4 mm Hg), cardiac sympathetic tone (96±7 versus 75±6 bpm), and decreased cardiac parasympathetic tone (16±2 versus 36±3 versus bpm) compared with saline-infused controls in conscious rats. The Ang II-infused group also showed an impaired baroreflex control of heart rate (-1.50±0.1 versus -2.50±0.3 bpm/mm Hg), potentiation of the chemoreflex pressor response (53±7 versus 30±7 mm Hg) and increased number of FosB-labeled cells (53±3 versus 19±4) in the PVN. Concomitant with the activation of the PVN, there was an increased expression of HIF-1α and N-Methyl-D-Aspartate-type1 receptors in the PVN. Further, Ang II-infusion showed increased renal sympathetic nerve activity (20.5±2.3% versus 6.4±1.9% of Max) and 3-fold enhanced renal sympathetic nerve activity responses to microinjection of N-methyl-D-aspartate (200 pmol) into the PVN of anesthetized rats. Further, silencing of HIF-1α in NG108 cells abrogated the expression of N-methyl-D-aspartate-N-methyl-D-aspartate-type1 induced by Ang II. Taken together, our studies suggest a novel Ang II-HIF-1α-N-methyl-D-aspartate receptor-mediated activation of preautonomic neurons in the PVN, resulting in increased sympathetic outflow and alterations in baro- and chemoreflexes.
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Affiliation(s)
- Neeru M Sharma
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (N.M.S., A.S.H., K.K., S.S.N., K.P.P.)
| | - Andréa S Haibara
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (N.M.S., A.S.H., K.K., S.S.N., K.P.P.)
| | - Kenichi Katsurada
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (N.M.S., A.S.H., K.K., S.S.N., K.P.P.)
| | - Shyam S Nandi
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (N.M.S., A.S.H., K.K., S.S.N., K.P.P.)
| | - Xuefei Liu
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion (X.L., H.Z.)
| | - Hong Zheng
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion (X.L., H.Z.)
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (N.M.S., A.S.H., K.K., S.S.N., K.P.P.)
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18
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Kim ER, Xu Y, Cassidy RM, Lu Y, Yang Y, Tian J, Li DP, Van Drunen R, Ribas-Latre A, Cai ZL, Xue M, Arenkiel BR, Eckel-Mahan K, Xu Y, Tong Q. Paraventricular hypothalamus mediates diurnal rhythm of metabolism. Nat Commun 2020; 11:3794. [PMID: 32732906 PMCID: PMC7393104 DOI: 10.1038/s41467-020-17578-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 07/09/2020] [Indexed: 12/18/2022] Open
Abstract
Defective rhythmic metabolism is associated with high-fat high-caloric diet (HFD) feeding, ageing and obesity; however, the neural basis underlying HFD effects on diurnal metabolism remains elusive. Here we show that deletion of BMAL1, a core clock gene, in paraventricular hypothalamic (PVH) neurons reduces diurnal rhythmicity in metabolism, causes obesity and diminishes PVH neuron activation in response to fast-refeeding. Animal models mimicking deficiency in PVH neuron responsiveness, achieved through clamping PVH neuron activity at high or low levels, both show obesity and reduced diurnal rhythmicity in metabolism. Interestingly, the PVH exhibits BMAL1-controlled rhythmic expression of GABA-A receptor γ2 subunit, and dampening rhythmicity of GABAergic input to the PVH reduces diurnal rhythmicity in metabolism and causes obesity. Finally, BMAL1 deletion blunts PVH neuron responses to external stressors, an effect mimicked by HFD feeding. Thus, BMAL1-driven PVH neuron responsiveness in dynamic activity changes involving rhythmic GABAergic neurotransmission mediates diurnal rhythmicity in metabolism and is implicated in diet-induced obesity.
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Affiliation(s)
- Eun Ran Kim
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Yuanzhong Xu
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Ryan M Cassidy
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
- Graduate Program in Neuroscience of MD Anderson and UTHealth Graduate School, Houston, TX, 77030, USA
| | - Yungang Lu
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Yongjie Yang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Jinbin Tian
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
- Department of Integrative Physiology and Pharmacology, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - De-Pei Li
- Department of Critical Care and Respiratory Care, Division of Anesthesiology, Critical Care and Pain Medicine, University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Rachel Van Drunen
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
- Graduate Program in Neuroscience of MD Anderson and UTHealth Graduate School, Houston, TX, 77030, USA
| | - Aleix Ribas-Latre
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Zhao-Lin Cai
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
- Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, 77030, USA
| | - Mingshan Xue
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
- Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, 77030, USA
| | - Benjamin R Arenkiel
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, 77030, USA
| | - Kristin Eckel-Mahan
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas McGovern Medical School, Houston, TX, 77030, USA.
- Graduate Program in Neuroscience of MD Anderson and UTHealth Graduate School, Houston, TX, 77030, USA.
- Department of Neurobiology and Anatomy of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
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19
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Srivastava A, Das B, Yao AY, Yan R. Metabotropic Glutamate Receptors in Alzheimer's Disease Synaptic Dysfunction: Therapeutic Opportunities and Hope for the Future. J Alzheimers Dis 2020; 78:1345-1361. [PMID: 33325389 PMCID: PMC8439550 DOI: 10.3233/jad-201146] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the presence of neuritic plaques and neurofibrillary tangles. The impaired synaptic plasticity and dendritic loss at the synaptic level is an early event associated with the AD pathogenesis. The abnormal accumulation of soluble oligomeric amyloid-β (Aβ), the major toxic component in amyloid plaques, is viewed to trigger synaptic dysfunctions through binding to several presynaptic and postsynaptic partners and thus to disrupt synaptic transmission. Over time, the abnormalities in neural transmission will result in cognitive deficits, which are commonly manifested as memory loss in AD patients. Synaptic plasticity is regulated through glutamate transmission, which is mediated by various glutamate receptors. Here we review recent progresses in the study of metabotropic glutamate receptors (mGluRs) in AD cognition. We will discuss the role of mGluRs in synaptic plasticity and their modulation as a possible strategy for AD cognitive improvement.
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Affiliation(s)
- Akriti Srivastava
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, USA
| | - Brati Das
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, USA
| | - Annie Y. Yao
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, USA
| | - Riqiang Yan
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, USA
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20
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Ovalles AC, Contoreggi NH, Marques-Lopes J, Van Kempen TA, Iadecola C, Waters EM, Glass MJ, Milner TA. Plasma Membrane Affiliated AMPA GluA1 in Estrogen Receptor β-containing Paraventricular Hypothalamic Neurons Increases Following Hypertension in a Mouse Model of Post-menopause. Neuroscience 2019; 423:192-205. [PMID: 31682817 DOI: 10.1016/j.neuroscience.2019.09.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 12/11/2022]
Abstract
Sex and ovarian function contribute to hypertension susceptibility, however, the mechanisms are not well understood. Prior studies show that estrogens and neurogenic factors, including hypothalamic glutamatergic NMDA receptor plasticity, play significant roles in rodent hypertension. Here, we investigated the role of sex and ovarian failure on AMPA receptor plasticity in estrogen-sensitive paraventricular nucleus (PVN) neurons in naïve and angiotensin II (AngII) infused male and female mice and female mice at early and late stages of accelerated ovarian failure (AOF). High-resolution electron microscopy was used to assess the subcellular distribution of AMPA GluA1 in age-matched male and female estrogen receptor beta (ERβ) enhanced green fluorescent protein (EGFP) reporter mice as well as female ERβ-EGFP mice treated with 4-vinylcyclohexene diepoxide. In the absence of AngII, female mice at a late stage of AOF displayed higher levels of GluA1 on the plasma membrane, indicative of functional protein, in ERβ-expressing PVN dendrites when compared to male, naïve female and early stage AOF mice. Following slow-pressor AngII infusion, males, as well as early and late stage AOF females had elevated blood pressure. Significantly, only late stage-AOF female mice infused with AngII had an increase in GluA1 near the plasma membrane in dendrites of ERβ-expressing PVN neurons. In contrast, prior studies reported that plasmalemmal NMDA GluN1 increased in ERβ-expressing PVN dendrites in males and early, but not late stage AOF females. Together, these findings reveal that early and late stage AOF female mice display unique molecular signatures of long-lasting synaptic strength prior to, and following hypertension.
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Affiliation(s)
- Astrid C Ovalles
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA
| | - Natalina H Contoreggi
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA
| | - Jose Marques-Lopes
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA
| | - Tracey A Van Kempen
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA
| | - Elizabeth M Waters
- Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Michael J Glass
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA.
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY 10065, USA; Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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Left Ventricular Hypertrophy: Roles of Mitochondria CYP1B1 and Melatonergic Pathways in Co-Ordinating Wider Pathophysiology. Int J Mol Sci 2019; 20:ijms20164068. [PMID: 31434333 PMCID: PMC6720185 DOI: 10.3390/ijms20164068] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/11/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023] Open
Abstract
Left ventricular hypertrophy (LVH) can be adaptive, as arising from exercise, or pathological, most commonly when driven by hypertension. The pathophysiology of LVH is consistently associated with an increase in cytochrome P450 (CYP)1B1 and mitogen-activated protein kinases (MAPKs) and a decrease in sirtuins and mitochondria functioning. Treatment is usually targeted to hypertension management, although it is widely accepted that treatment outcomes could be improved with cardiomyocyte hypertrophy targeted interventions. The current article reviews the wide, but disparate, bodies of data pertaining to LVH pathoetiology and pathophysiology, proposing a significant role for variations in the N-acetylserotonin (NAS)/melatonin ratio within mitochondria in driving the biological underpinnings of LVH. Heightened levels of mitochondria CYP1B1 drive the ‘backward’ conversion of melatonin to NAS, resulting in a loss of the co-operative interactions of melatonin and sirtuin-3 within mitochondria. NAS activates the brain-derived neurotrophic factor receptor, TrkB, leading to raised trophic signalling via cyclic adenosine 3′,5′-monophosphate (cAMP)-response element binding protein (CREB) and the MAPKs, which are significantly increased in LVH. The gut microbiome may be intimately linked to how stress and depression associate with LVH and hypertension, with gut microbiome derived butyrate, and other histone deacetylase inhibitors, significant modulators of the melatonergic pathways and LVH more generally. This provides a model of LVH that has significant treatment and research implications.
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Basting T, Xu J, Mukerjee S, Epling J, Fuchs R, Sriramula S, Lazartigues E. Glutamatergic neurons of the paraventricular nucleus are critical contributors to the development of neurogenic hypertension. J Physiol 2018; 596:6235-6248. [PMID: 30151830 PMCID: PMC6292814 DOI: 10.1113/jp276229] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/17/2018] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS Recurrent periods of over-excitation in the paraventricular nucleus (PVN) of the hypothalamus could contribute to chronic over-activation of this nucleus and thus enhanced sympathetic drive. Stimulation of the PVN glutamatergic population utilizing channelrhodopsin-2 leads to an immediate frequency-dependent increase in baseline blood pressure. Partial lesions of glutamatergic neurons of the PVN (39.3%) result in an attenuated rise in blood pressure following Deoxycorticosterone acetate (DOCA)-salt treatment and reduced index of sympathetic activity. These data suggest that stimulation of PVN glutamatergic neurons is sufficient to cause autonomic dysfunction and drive the increase in blood pressure during hypertension. ABSTRACT Neuro-cardiovascular dysregulation leads to increased sympathetic activity and neurogenic hypertension. The paraventricular nucleus (PVN) of the hypothalamus is a key hub for blood pressure (BP) control, producing or relaying the increased sympathetic tone in hypertension. We hypothesize that increased central sympathetic drive is caused by chronic over-excitation of glutamatergic PVN neurons. We tested how stimulation or lesioning of excitatory PVN neurons in conscious mice affects BP, baroreflex and sympathetic activity. Glutamatergic PVN neurons were unilaterally transduced with channelrhodopsin-2 using an adeno-associated virus (CamKII-ChR2-eYFP-AAV2) in wildtype mice (n = 7) to assess the impact of acute stimulation of excitatory PVN neurons selectively on resting BP in conscious mice. Stimulation of the PVN glutamatergic population resulted in an immediate frequency-dependent (2, 10 and 20 Hz) increase in BP from baseline by ∼9 mmHg at 20 Hz stimulation (P < 0.001). Additionally, in vGlut2-cre mice glutamatergic neurons of the PVN were bilaterally lesioned utilizing a cre-dependent caspase (AAV2-flex-taCASP3-TEVp). Resting BP and urinary noradrenaline (norepinephrine) levels were then recorded in conscious mice before and after DOCA-salt hypertension. Partial lesions of glutamatergic neurons of the PVN (39.3%, P < 0.05) resulted in an attenuated rise in BP following DOCA-salt treatment (P < 0.05 at 7 day time point, n = 8). Noradrenaline levels as an index of sympathetic activity between the lesion and wildtype groups showed a significant reduction after DOCA-salt treatment in the lesioned animals (P < 0.05). These experiments suggest that stimulation of PVN glutamatergic neurons is sufficient to cause autonomic dysfunction and drive the increase in BP.
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Affiliation(s)
- Tyler Basting
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
| | - Jiaxi Xu
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
| | - Snigdha Mukerjee
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
| | - Joel Epling
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
| | - Robert Fuchs
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
| | - Srinivas Sriramula
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
- Department of Pharmacology and Toxicology, Brody School of MedicineEast Carolina UniversityGreenvilleNC27834USA
| | - Eric Lazartigues
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA70112USA
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA70112USA
- Neuroscience Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA70112USA
- Southeast Louisiana Veterans Health Care SystemNew OrleansLAUSA
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23
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Dampney RA, Michelini LC, Li DP, Pan HL. Regulation of sympathetic vasomotor activity by the hypothalamic paraventricular nucleus in normotensive and hypertensive states. Am J Physiol Heart Circ Physiol 2018; 315:H1200-H1214. [PMID: 30095973 PMCID: PMC6297824 DOI: 10.1152/ajpheart.00216.2018] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 07/13/2018] [Accepted: 07/25/2018] [Indexed: 12/22/2022]
Abstract
The hypothalamic paraventricular nucleus (PVN) is a unique and important brain region involved in the control of cardiovascular, neuroendocrine, and other physiological functions pertinent to homeostasis. The PVN is a major source of excitatory drive to the spinal sympathetic outflow via both direct and indirect projections. In this review, we discuss the role of the PVN in the regulation of sympathetic output in normal physiological conditions and in hypertension. In normal healthy animals, the PVN presympathetic neurons do not appear to have a major role in sustaining resting sympathetic vasomotor activity or in regulating sympathetic responses to short-term homeostatic challenges such as acute hypotension or hypoxia. Their role is, however, much more significant during longer-term challenges, such as sustained water deprivation, chronic intermittent hypoxia, and pregnancy. The PVN also appears to have a major role in generating the increased sympathetic vasomotor activity that is characteristic of multiple forms of hypertension. Recent studies in the spontaneously hypertensive rat model have shown that impaired inhibitory and enhanced excitatory synaptic inputs to PVN presympathetic neurons are the basis for the heightened sympathetic outflow in hypertension. We discuss the molecular mechanisms underlying the presynaptic and postsynaptic alterations in GABAergic and glutamatergic inputs to PVN presympathetic neurons in hypertension. In addition, we discuss the ability of exercise training to correct sympathetic hyperactivity by restoring blood-brain barrier integrity, reducing angiotensin II availability, and decreasing oxidative stress and inflammation in the PVN.
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Affiliation(s)
- Roger A Dampney
- Department of Physiology, University of Sydney , Sydney, New South Wales , Australia
| | - Lisete C Michelini
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo , São Paulo , Brazil
| | - De-Pei Li
- Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center , Houston, Texas
| | - Hui-Lin Pan
- Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center , Houston, Texas
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Neural Mechanisms of Autonomic Dysfunction in Neurological Diseases. Neural Plast 2017; 2017:2050191. [PMID: 29445550 PMCID: PMC5763130 DOI: 10.1155/2017/2050191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 12/07/2017] [Indexed: 11/22/2022] Open
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