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Tasso M, Kageyama K, Iwasaki Y, Watanuki Y, Niioka K, Takayasu S, Daimon M. Growth differentiation factor-15 stimulates the synthesis of corticotropin-releasing factor in hypothalamic 4B cells. Peptides 2023; 170:171112. [PMID: 37918484 DOI: 10.1016/j.peptides.2023.171112] [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: 04/26/2023] [Revised: 10/11/2023] [Accepted: 10/27/2023] [Indexed: 11/04/2023]
Abstract
Growth differentiation factor-15 (GDF15) is a stress-activated cytokine that regulates cell growth and inflammatory and stress responses. We previously reported the role and regulation of GDF15 in pituitary corticotrophs. Dexamethasone increases Gdf15 gene expression levels and production. GDF15 suppresses adrenocorticotropic hormone synthesis in pituitary corticotrophs and subsequently mediates the negative feedback effect of glucocorticoids. Here, we analyzed corticotropin-releasing factor (Crf) promoter activity in hypothalamic 4B cells transfected with promoter-driven luciferase reporter constructs. The effects of time and GDF15 concentration on Crf mRNA levels were analyzed using quantitative real-time polymerase chain reaction. Glial cell-derived neurotrophic factor family receptor α-like (GFRAL) protein is expressed in 4B cells. GDF15 increased Crf promoter activity and Crf mRNA levels in 4B cells. The protein kinase A and C pathways also contributed to the GDF15-induced increase in Crf gene expression. GDF15 stimulates GFRAL, subsequently increasing the phosphorylation of AKT, an extracellular signal-related kinase, and the cAMP response element-binding protein. Therefore, GDF15-dependent pathways may be involved in regulating Crf expression under stressful conditions in hypothalamic cells.
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Affiliation(s)
- Mizuki Tasso
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
| | - Yasumasa Iwasaki
- Suzuka University of Medical Science, 1001-1 Kishioka-cho, Suzuka, Mie 510-0293, Japan
| | - Yutaka Watanuki
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kanako Niioka
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Shinobu Takayasu
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
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Kovács LÁ, Füredi N, Ujvári B, Golgol A, Gaszner B. Age-Dependent FOSB/ΔFOSB Response to Acute and Chronic Stress in the Extended Amygdala, Hypothalamic Paraventricular, Habenular, Centrally-Projecting Edinger-Westphal, and Dorsal Raphe Nuclei in Male Rats. Front Aging Neurosci 2022; 14:862098. [PMID: 35592695 PMCID: PMC9110804 DOI: 10.3389/fnagi.2022.862098] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 04/04/2022] [Indexed: 11/29/2022] Open
Abstract
FOS proteins are early-responding gene products that contribute to the formation of activator protein-1. Several acute and chronic stimuli lead to Fos gene expression, accompanied by an increase of nuclear FOS, which appears to decline with aging. FOSB is another marker to detect acute cellular response, while ΔFOSB mirrors long-lasting changes in neuronal activity upon chronic stress. The notion that the occurrence of stress-related mood disorders shows some age dependence suggests that the brain's stress sensitivity is also a function of age. To study age-dependent stress vulnerability at the immediate-early gene level, we aimed to describe how the course of aging affects the neural responses of FOSB/ΔFOSB in the acute restraint stress (ARS), and chronic variable mild stress (CVMS) in male rats. Fourteen brain areas [central, medial, basolateral (BLA) amygdala; dorsolateral- (BNSTdl), oval- (BNSTov), dorsomedial-, ventral- (BNSTv), and fusiform- (BNSTfu) divisions of the bed nucleus of the stria terminalis; medial and lateral habenula, hypothalamic paraventricular nucleus (PVN), centrally-projecting Edinger-Westphal nucleus, dorsal raphe nucleus, barrel field of somatosensory cortex (S1)] were examined in the course of aging. Eight age groups [1-month-old (M), 1.5 M, 2 M, 3 M, 6 M, 12 M, 18 M, and 24 M] of rats were exposed to a single ARS vs. controls. In addition, rats in six age groups (2, 3, 6, 12, 18, and 24 M) were subjected to CVMS. The FOSB/ΔFOSB immunoreactivity (IR) was a function of age in both controls, ARS- and CVMS-exposed rats. ARS increased the FOSB/ΔFOSB in all nuclei (except in BLA), but only BNSTfu, BNSTv, and PVN reacted throughout the examined lifespan. The CVMS did not increase the FOSB/ΔFOSB in BLA, BNSTov, BNSTdl, and S1. PVN showed a constantly maintained FOSB/ΔFOSB IR during the examined life period. The maximum stress-evoked FOSB/ΔFOSB signal was detected at 2-3 M periods in the ARS- and at 6 M, 18 M in CVMS- model. Corresponding to our previous observations on FOS, the FOSB/ΔFOSB response to stress decreased with age in most of the examined nuclei. Only the PVN exerted a sustained age-independent FOSB/ΔFOSB, which may reflect the long-lasting adaptation response and plasticity of neurons that maintain the hypothalamus-pituitary-adrenal axis response throughout the lifespan.
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Affiliation(s)
- László Ákos Kovács
- Department of Anatomy, Research Group for Mood Disorders, Medical School, University of Pécs, Pécs, Hungary
- Center for Neuroscience & Szentagothai Research Center, Pécs University, Pécs, Hungary
| | - Nóra Füredi
- Department of Anatomy, Research Group for Mood Disorders, Medical School, University of Pécs, Pécs, Hungary
- Center for Neuroscience & Szentagothai Research Center, Pécs University, Pécs, Hungary
| | - Balázs Ujvári
- Department of Anatomy, Research Group for Mood Disorders, Medical School, University of Pécs, Pécs, Hungary
| | - Abolfazl Golgol
- Department of Anatomy, Research Group for Mood Disorders, Medical School, University of Pécs, Pécs, Hungary
| | - Balázs Gaszner
- Department of Anatomy, Research Group for Mood Disorders, Medical School, University of Pécs, Pécs, Hungary
- Center for Neuroscience & Szentagothai Research Center, Pécs University, Pécs, Hungary
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Kageyama K, Iwasaki Y, Daimon M. Hypothalamic Regulation of Corticotropin-Releasing Factor under Stress and Stress Resilience. Int J Mol Sci 2021; 22:ijms222212242. [PMID: 34830130 PMCID: PMC8621508 DOI: 10.3390/ijms222212242] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/09/2021] [Accepted: 11/11/2021] [Indexed: 02/07/2023] Open
Abstract
This review addresses the molecular mechanisms of corticotropin-releasing factor (CRF) regulation in the hypothalamus under stress and stress resilience. CRF in the hypothalamus plays a central role in regulating the stress response. CRF stimulates adrenocorticotropic hormone (ACTH) release from the anterior pituitary. ACTH stimulates glucocorticoid secretion from the adrenal glands. Glucocorticoids are essential for stress coping, stress resilience, and homeostasis. The activated hypothalamic-pituitary-adrenal axis is suppressed by the negative feedback from glucocorticoids. Glucocorticoid-dependent repression of cAMP-stimulated Crf promoter activity is mediated by both the negative glucocorticoid response element and the serum response element. Conversely, the inducible cAMP-early repressor can suppress the stress response via inhibition of the cAMP-dependent Crf gene, as can the suppressor of cytokine signaling-3 in the hypothalamus. CRF receptor type 1 is mainly involved in a stress response, depression, anorexia, and seizure, while CRF receptor type 2 mediates “stress coping” mechanisms such as anxiolysis in the brain. Differential effects of FK506-binding immunophilins, FKBP4 and FKBP5, contribute to the efficiency of glucocorticoids under stress resilience. Together, a variety of factors contribute to stress resilience. All these factors would have the differential roles under stress resilience.
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Affiliation(s)
- Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki 036-8562, Aomori, Japan;
- Correspondence: ; Tel.: +81-172-39-5062
| | - Yasumasa Iwasaki
- Department of Clinical Nutrition Management Nutrition Course, Faculty of Health Science, Suzuka University of Medical Science, 1001-1 Kishioka-cho, Suzuka 510-0293, Mie, Japan;
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki 036-8562, Aomori, Japan;
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Kovács LÁ, Berta G, Csernus V, Ujvári B, Füredi N, Gaszner B. Corticotropin-Releasing Factor-Producing Cells in the Paraventricular Nucleus of the Hypothalamus and Extended Amygdala Show Age-Dependent FOS and FOSB/DeltaFOSB Immunoreactivity in Acute and Chronic Stress Models in the Rat. Front Aging Neurosci 2019; 11:274. [PMID: 31649527 PMCID: PMC6794369 DOI: 10.3389/fnagi.2019.00274] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/24/2019] [Indexed: 01/01/2023] Open
Abstract
Corticotropin-releasing factor (CRF) immunoreactive (ir) neurons of the paraventricular nucleus of the hypothalamus (PVN) play pivotal role in the coordination of stress response. CRF-producing cells in the central nucleus of amygdala (CeA) and oval division of the bed nucleus of stria terminalis (BNSTov) are also involved in stress adaptation and mood control. Immediate early gene products, subunits of the transcription factor activator protein 1 (AP1) are commonly used as acute (FOS) and/or chronic (FOSB/deltaFOSB) markers for the neuronal activity in stress research. It is well known that the course of aging affects stress adaptation, but little is known about the aging-related stress sensitivity of CRF neurons. To the best of our knowledge, the stress-induced neuronal activity of CRF neurons in the course of aging in acute and chronic stress models was not studied systematically yet. Therefore, the aim of the present study was to quantify the acute restraint stress (ARS) and chronic variable mild stress (CVMS) evoked neuronal activity in CRF cells of the PVN, CeA, and BNSTov using triple-label immunofluorescence throughout the whole lifespan in the rat. We hypothesized that the FOS and FOSB content of CRF cells upon ARS or CVMS decreases with age. Our results showed that the FOS and FOSB response to ARS declined with age in the PVN-CRF cells. BNSTov and CeA CRF cells did not show remarkable stress-induced elevation of these markers neither in ARS, nor in CVMS. Exposure to CVMS resulted in an age-independent significant increase of FOSB/delta FOSB immunosignal in PVN-CRF neurons. Unexpectedly, we detected a remarkable stress-independent FOSB/deltaFOSB signal in CeA- and BNSTov-CRF cells that declined with the course of aging. In summary, PVN-CRF cells show decreasing acute stress sensitivity (i.e., FOS and FOSB immunoreactivity) with the course of aging, while their (FOSB/deltaFOSB) responsivity to chronic challenge is maintained till senescence. Stress exposure does not affect the occurrence of the examined Fos gene products in CeA- and BNSTov-CRF cells remarkably suggesting that their contribution to stress adaptation response does not require AP1-controlled transcriptional changes.
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Affiliation(s)
- László Á Kovács
- Department of Anatomy, University of Pécs Medical School, Pécs, Hungary.,Centre for Neuroscience, Pécs University, Pécs, Hungary
| | - Gergely Berta
- Department of Medical Biology and Central Electron Microscope Laboratory, University of Pécs Medical School, Pécs, Hungary
| | - Valér Csernus
- Department of Anatomy, University of Pécs Medical School, Pécs, Hungary
| | - Balázs Ujvári
- Department of Anatomy, University of Pécs Medical School, Pécs, Hungary.,Centre for Neuroscience, Pécs University, Pécs, Hungary
| | - Nóra Füredi
- Department of Anatomy, University of Pécs Medical School, Pécs, Hungary.,Centre for Neuroscience, Pécs University, Pécs, Hungary
| | - Balázs Gaszner
- Department of Anatomy, University of Pécs Medical School, Pécs, Hungary.,Centre for Neuroscience, Pécs University, Pécs, Hungary
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Differential Expression of Striatal ΔFosB mRNA and FosB mRNA After Different Levodopa Treatment Regimens in a Rat Model of Parkinson's Disease. Neurotox Res 2019; 35:563-574. [PMID: 30645726 DOI: 10.1007/s12640-018-9993-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 12/10/2018] [Accepted: 12/26/2018] [Indexed: 10/27/2022]
Abstract
Levodopa-induced dyskinesia (LID) is the main side effect associated with levodopa treatment and represents the biggest challenge for Parkinson's disease therapy. While the overexpression of ΔFosB transcription factor is related to the development of LID, few studies have been undertaken on fosB gene transcriptional regulation induced by levodopa in vivo. The aim of this study is to evaluate the expression of ΔFosB mRNA and FosB mRNA in the striatum after acute, chronic, and subchronic levodopa treatment in rats with unilateral 6-OHDA-lesion in the medial forebrain bundle. qRT-PCR was used to compare the levels of ΔFosB and FosB mRNA expression in the dopamine-denervated striatum following levodopa treatment. While the results obtained after a single levodopa dose indicate a significant increase of ∆FosB mRNA expression in the striatum 1 h post-injection, the levels returned to baseline values after 24 h. After subchronic levodopa treatment, the levels of ∆FosB and FosB mRNA expression were lower 1 h post-administration of levodopa in comparison with acute effect. However, after chronic levodopa treatment, ∆FosB mRNA expression in the striatum persisted in dyskinetic rats only, and positive correlation was found between the levels of ∆FosB mRNA expression 1 h after levodopa administration and the level of dyskinetic severity. In summary, acute levodopa treatment led to highly increased levels of ∆FosB mRNA expression in the striatum. While repeated administration induced a partial desensitization of the fosB gene in the striatum, it did not suppress its activity completely, which could explain why dyskinesia appears after chronic levodopa treatment.
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Itoi K, Motoike I, Liu Y, Clokie S, Iwasaki Y, Uchida K, Sato T, Aguilera G. Genome-Wide Analysis of Glucocorticoid-Responsive Transcripts in the Hypothalamic Paraventricular Region of Male Rats. Endocrinology 2019; 160:38-54. [PMID: 30364965 PMCID: PMC6302960 DOI: 10.1210/en.2018-00535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 10/19/2018] [Indexed: 11/19/2022]
Abstract
Glucocorticoids (GCs) are essential for stress adaptation, acting centrally and in the periphery. Corticotropin-releasing factor (CRF), a major regulator of adrenal GC synthesis, is produced in the paraventricular nucleus of the hypothalamus (PVH), which contains multiple neuroendocrine and preautonomic neurons. GCs may be involved in diverse regulatory mechanisms in the PVH, but the target genes of GCs are largely unexplored except for the CRF gene (Crh), a well-known target for GC negative feedback. Using a genome-wide RNA-sequencing analysis, we identified transcripts that changed in response to either high-dose corticosterone (Cort) exposure for 12 days (12-day high Cort), corticoid deprivation for 7 days (7-day ADX), or acute Cort administration. Among others, canonical GC target genes were upregulated prominently by 12-day high Cort. Crh was upregulated or downregulated most prominently by either 7-day ADX or 12-day high Cort, emphasizing the recognized feedback effects of GC on the hypothalamic-pituitary-adrenal (HPA) axis. Concomitant changes in vasopressin and apelin receptor gene expression are likely to contribute to HPA repression. In keeping with the pleotropic cellular actions of GCs, 7-day ADX downregulated numerous genes of a broad functional spectrum. The transcriptome response signature differed markedly between acute Cort injection and 12-day high Cort. Remarkably, six immediate early genes were upregulated 1 hour after Cort injection, which was confirmed by quantitative reverse transcription PCR and semiquantitative in situ hybridization. This study may provide a useful database for studying the regulatory mechanisms of GC-dependent gene expression and repression in the PVH.
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Affiliation(s)
- Keiichi Itoi
- Laboratory of Information Biology, Graduate School of Information Sciences, Tohoku University, Sendai, Japan
- Department of Neuroendocrinology, Graduate School of Medicine, Tohoku University, Sendai, Japan
- Correspondence: Keiichi Itoi, MD, PhD, Graduate School of Information Biology, Tohoku University, 6-3-09, Aramaki-aza Aoba, Sendai 980-8579, Japan. E-mail:
| | - Ikuko Motoike
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Ying Liu
- Section on Endocrine Physiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Sam Clokie
- Section of Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | | | - Katsuya Uchida
- Laboratory of Information Biology, Graduate School of Information Sciences, Tohoku University, Sendai, Japan
| | - Tatsuya Sato
- Laboratory of Information Biology, Graduate School of Information Sciences, Tohoku University, Sendai, Japan
| | - Greti Aguilera
- Section on Endocrine Physiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
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Zhu J, Chen Z, Tian J, Meng Z, Ju M, Wu G, Tian Z. miR-34b attenuates trauma-induced anxiety-like behavior by targeting CRHR1. Int J Mol Med 2017; 40:90-100. [PMID: 28498394 PMCID: PMC5466391 DOI: 10.3892/ijmm.2017.2981] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/25/2017] [Indexed: 02/04/2023] Open
Abstract
Exposure to trauma is a potential contributor to anxiety; however, the molecular mechanisms responsible for trauma-induced anxiety require further clarification. In this study, in an aim to explore these mechanisms, we observed the changes in the hypothalamic pituitary adrenal (HPA) axis using a radioimmunoassay and the changes in anxiety-like behavior using the open field test and elevated plus maze test in a rat model following intervention with NBI-27914, a specific corticotropin-releasing hormone receptor 1 (CRHR1) antagonist. CRHR1 was found to be involved in trauma-induced anxiety. We then applied bioinformatic analysis to screen microRNAs (miRNAs or miRs) that target CRHR1, and miR-34b was determined to negatively regulate CRHR1 mRNA in primary hypothalamic neurons. The overexpression of miR-34b in the paraventricular nucleus (PVN) by a miRNA agomir using a drug delivery system decreased the hyperactivity of the HPA axis and anxiety-like behavior. Overall, the involvement of the HPA axis in trauma-induced anxiety was demonstrated, and trauma-induced anxiety was attenuated by decreasing the hyperactivity of the HPA axis via miR-34b by targeting CRHR1.
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Affiliation(s)
- Jing Zhu
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
| | - Zhejun Chen
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
| | - Jinxing Tian
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P.R. China
| | - Zehui Meng
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
| | - Mingda Ju
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
| | - Gencheng Wu
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
| | - Zhanzhuang Tian
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Institute of Acupuncture Research, WHO Collaborating Centre for Traditional Medicine, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai 200032, P.R. China
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Saxena A, Bachelor M, Park YH, Carreno FR, Nedungadi TP, Cunningham JT. Angiotensin II induces membrane trafficking of natively expressed transient receptor potential vanilloid type 4 channels in hypothalamic 4B cells. Am J Physiol Regul Integr Comp Physiol 2014; 307:R945-55. [PMID: 25080500 DOI: 10.1152/ajpregu.00224.2014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Transient receptor potential vanilloid family type 4 (TRPV4) channels are expressed in central neuroendocrine neurons and have been shown to be polymodal in other systems. We previously reported that in the rodent, a model of dilutional hyponatremia associated with hepatic cirrhosis, TRPV4 expression is increased in lipid rafts from the hypothalamus and that this effect may be angiotensin dependent. In this study, we utilized the immortalized neuroendocrine rat hypothalamic 4B cell line to more directly test the effects of angiotensin II (ANG II) on TRPV4 expression and function. Our results demonstrate the expression of corticotropin-releasing factor (CRF) transcripts, for sex-determining region Y (SRY) (male genotype), arginine vasopressin (AVP), TRPV4, and ANG II type 1a and 1b receptor in 4B cells. After a 1-h incubation in ANG II (100 nM), 4B cells showed increased TRPV4 abundance in the plasma membrane fraction, and this effect was prevented by the ANG II type 1 receptor antagonist losartan (1 μM) and by a Src kinase inhibitor PP2 (10 μM). Ratiometric calcium imaging experiments demonstrated that ANG II incubation potentiated TRPV4 agonist (GSK 1016790A, 20 nM)-induced calcium influx (control 18.4 ± 2.8% n = 5 and ANG II 80.5 ± 2.4% n = 5). This ANG II-induced increase in calcium influx was also blocked by 1 μM losartan and 10 μM PP2 (losartan 26.4 ± 3.8% n = 5 and PP2 19.7 ± 3.9% n = 5). Our data suggests that ANG II can increase TRPV4 channel membrane expression in 4B cells through its action on AT1R involving a Src kinase pathway.
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Affiliation(s)
- Ashwini Saxena
- Department of Integrative Physiology and Anatomy and Cardiovascular Research Institute, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas
| | - Martha Bachelor
- Department of Integrative Physiology and Anatomy and Cardiovascular Research Institute, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas
| | - Yong H Park
- Department of Pharmacology and Neuroscience & North Texas Eye Research Institute, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas; and
| | - Flavia R Carreno
- Department of Pharmacology & Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - T Prashant Nedungadi
- Department of Integrative Physiology and Anatomy and Cardiovascular Research Institute, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas
| | - J Thomas Cunningham
- Department of Integrative Physiology and Anatomy and Cardiovascular Research Institute, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas;
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