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Eguchi S, Torimoto K, Adebiyi A, Kanthakumar P, Bomfim GF, Wenceslau CF, Dahlen SA, Osei-Owusu P. Milestone Papers on Signal Transduction Mechanisms of Hypertension and Its Complications. Hypertension 2024; 81:977-990. [PMID: 38372140 PMCID: PMC11023792 DOI: 10.1161/hypertensionaha.123.21365] [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: 02/20/2024]
Abstract
To celebrate 100 years of American Heart Association-supported cardiovascular disease research, this review article highlights milestone papers that have significantly contributed to the current understanding of the signaling mechanisms driving hypertension and associated cardiovascular disorders. This article also includes a few of the future research directions arising from these critical findings. To accomplish this important mission, 4 principal investigators gathered their efforts to cover distinct yet intricately related areas of signaling mechanisms pertaining to the pathogenesis of hypertension. The renin-angiotensin system, canonical and novel contractile and vasodilatory pathways in the resistance vasculature, vascular smooth muscle regulation by membrane channels, and noncanonical regulation of blood pressure and vascular function will be described and discussed as major subjects.
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Affiliation(s)
- Satoru Eguchi
- Department of Cardiovascular Science, Lewis Katz School of Medicine, Temple University
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University
| | - Keiichi Torimoto
- Department of Cardiovascular Science, Lewis Katz School of Medicine, Temple University
| | - Adebowale Adebiyi
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
- Department of Anesthesiology and Perioperative Medicine, University of Missouri, Columbia, Missouri
- NextGen Precision Health, University of Missouri, Columbia, Missouri
| | - Praghalathan Kanthakumar
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
- Department of Anesthesiology and Perioperative Medicine, University of Missouri, Columbia, Missouri
- NextGen Precision Health, University of Missouri, Columbia, Missouri
| | - Gisele F. Bomfim
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine
| | - Camilla Ferreira Wenceslau
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine
| | - Shelby A. Dahlen
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University
| | - Patrick Osei-Owusu
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University
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2
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Shiratori-Hayashi M, Tsuda M. IP 3R1-dependent astrocyte calcium signaling in chronic itch. Neurosci Res 2023; 187:40-44. [PMID: 36181909 DOI: 10.1016/j.neures.2022.09.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 09/27/2022] [Indexed: 10/14/2022]
Abstract
Astrocytes, the most abundant type of glial cell, are electrically non-excitable cells that use intracellular calcium (Ca2+) for functional regulation. Changes in intracellular Ca2+ concentration play important roles in the central nervous system (CNS), as they are involved in the release of gliotransmitters and the control of extracellular ion concentrations, thereby affecting the regulation of neuronal excitability, CNS homeostasis, and behavior. Intracellular calcium mobilization in astrocytes is known to be mediated via inositol 1,4,5-trisphosphate receptors (IP3Rs), particularly IP3R2, and its association with CNS pathogenesis has been widely reported. In addition, the existence of IP3R2-independent calcium signaling has recently been postulated; however, the detailed mechanisms and its role in astrocyte functions and CNS pathogenesis are still poorly understood. In this paper, we describe the putative mechanisms underlying IP3R1-dependent calcium signaling in astrocytes and its effects on the reactive state, compare this signaling with IP3R2-dependent calcium signaling, and discuss its contribution to chronic itch-like behavior.
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Affiliation(s)
- Miho Shiratori-Hayashi
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
| | - Makoto Tsuda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan; Kyushu University Institute for Advanced Study, Fukuoka, Japan.
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Critical Players and Therapeutic Targets in Chronic Itch. Int J Mol Sci 2022; 23:ijms23179935. [PMID: 36077340 PMCID: PMC9456029 DOI: 10.3390/ijms23179935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 12/04/2022] Open
Abstract
Chronic itch is one of the most prominent clinical characteristics of diverse systematic diseases. It is a devastating sensation in pathological diseases. Despite its importance, there are no FDA-labelled drugs specifically geared toward chronic itch. The associated complex pathogenesis and diverse causes escalate chronic itch to being one of the top challenges in healthcare. Humanized antibodies against IL-13, IL-4, and IL-31 proved effective in treatment of itch-associated atopic dermatitis but remain to be validated in chronic itch. There are still no satisfactory anti-itch therapeutics available toward itch-related neuropeptides including GRP, BNP, SST, CGRP, and SP. The newly identified potential itch targets including OSM, NMB, glutamate, periostin, and Serpin E1 have opened new avenues for therapeutic development. Proof-of-principle studies have been successfully performed on antagonists against these proteins and their receptors in itch treatment in animal models. Their translational interventions in humans need to be evaluated. It is of great importance to summarize and compare the newly emerging knowledge on chronic itch and its pathways to promote the development of novel anti-itch therapeutics. The goal of this review is to analyze the different physiologies and pathophysiologies of itch mediators, whilst assessing their suitability as new targets and discussing future therapeutic development.
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Pereira da Silva EA, Martín-Aragón Baudel M, Navedo MF, Nieves-Cintrón M. Ion channel molecular complexes in vascular smooth muscle. Front Physiol 2022; 13:999369. [PMID: 36091375 PMCID: PMC9459047 DOI: 10.3389/fphys.2022.999369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/02/2022] [Indexed: 11/30/2022] Open
Abstract
Ion channels that influence membrane potential and intracellular calcium concentration control vascular smooth muscle excitability. Voltage-gated calcium channels (VGCC), transient receptor potential (TRP) channels, voltage (KV), and Ca2+-activated K+ (BK) channels are key regulators of vascular smooth muscle excitability and contractility. These channels are regulated by various signaling cues, including protein kinases and phosphatases. The effects of these ubiquitous signaling molecules often depend on the formation of macromolecular complexes that provide a platform for targeting and compartmentalizing signaling events to specific substrates. This manuscript summarizes our current understanding of specific molecular complexes involving VGCC, TRP, and KV and BK channels and their contribution to regulating vascular physiology.
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Onoda N, Kawabata A, Hasegawa K, Sakakura M, Urakawa I, Seki M, Zenkoh J, Suzuki A, Suzuki Y. Spatial and single-cell transcriptome analysis reveals changes in gene expression in response to drug perturbation in rat kidney. DNA Res 2022; 29:dsac007. [PMID: 35325072 PMCID: PMC9014450 DOI: 10.1093/dnares/dsac007] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 03/22/2022] [Indexed: 12/25/2022] Open
Abstract
The kidney is a complex organ that consists of various types of cells. It is occasionally difficult to resolve molecular alterations and possible perturbations that the kidney experiences due to drug-induced damage. In this study, we performed spatial and single-cell transcriptome analysis of rat kidneys and constructed a precise rat renal cell atlas with spatial information. Using the constructed catalogue, we were able to characterize cells of several minor populations, such as macula densa or juxtaglomerular cells. Further inspection of the spatial gene expression data allowed us to identify the upregulation of genes involved in the renin regulating pathway in losartan-treated populations. Losartan is an angiotensin II receptor antagonist drug, and the observed upregulation of the renin pathway-related genes could be due to feedback from the hypotensive action of the drug. Furthermore, we found spatial heterogeneity in the response to losartan among the glomeruli. These results collectively indicate that integrated single-cell and spatial gene expression analysis is a powerful approach to reveal the detailed associations between the different cell types spanning the complicated renal compartments.
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Affiliation(s)
- Naoki Onoda
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
- Research Core Function Laboratories, Research Unit, R&D Division, Kyowa Kirin Co., Ltd., Machida-shi, Tokyo 194-8533, Japan
| | - Ayako Kawabata
- Research Core Function Laboratories, Research Unit, R&D Division, Kyowa Kirin Co., Ltd., Machida-shi, Tokyo 194-8533, Japan
| | - Kumi Hasegawa
- Biomedical Science Research Laboratories 1, Research Unit, R&D Division, Kyowa Kirin Co., Ltd., Machida-shi, Tokyo 194-8533, Japan
| | - Megumi Sakakura
- Research Core Function Laboratories, Research Unit, R&D Division, Kyowa Kirin Co., Ltd., Machida-shi, Tokyo 194-8533, Japan
| | - Itaru Urakawa
- Research Core Function Laboratories, Research Unit, R&D Division, Kyowa Kirin Co., Ltd., Machida-shi, Tokyo 194-8533, Japan
| | - Masahide Seki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
| | - Junko Zenkoh
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
| | - Ayako Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
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Reid C, Romero M, Chang SB, Osman N, Puglisi JL, Wilson CG, Blood AB, Zhang L, Wilson SM. Long-Term Hypoxia Negatively Influences Ca2+ Signaling in Basilar Arterial Myocytes of Fetal and Adult Sheep. Front Physiol 2022; 12:760176. [PMID: 35115953 PMCID: PMC8804533 DOI: 10.3389/fphys.2021.760176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 10/25/2021] [Indexed: 11/21/2022] Open
Abstract
Cerebral arterial vasoreactivity is vital to the regulation of cerebral blood flow. Depolarization of arterial myocytes elicits whole-cell Ca2+ oscillations as well as subcellular Ca2+ sparks due to activation of ryanodine receptors on the sarcoplasmic reticulum. Previous evidence illustrates that contraction of cerebral arteries from sheep and underlying Ca2+ signaling pathways are modified by age and that long-term hypoxia (LTH) causes aberrations in Ca2+ signaling pathways and downstream effectors impacting vasoregulation. We hypothesize that age and LTH affect the influence of membrane depolarization on whole-cell intracellular Ca2+ oscillations and sub-cellular Ca2+ spark activity in cerebral arteries. To test this hypothesis, we examined Ca2+ oscillatory and spark activities using confocal fluorescence imaging techniques of Fluo-4 loaded basilar arterial myocytes of low- and high-altitude term fetal (∼145 days of gestation) and adult sheep, where high-altitude pregnant and non-pregnant sheep were placed at 3,801 m for >100 days. Ca2+ oscillations and sparks were recorded using an in situ preparation evaluated in the absence or presence of 30 mM K+ (30K) to depolarize myocytes. Myocytes from adult animals tended to have a lower basal rate of whole-cell Ca2+ oscillatory activity and 30K increased the activity within cells. LTH decreased the ability of myocytes to respond to depolarization independent of age. These observations illustrate that both altitude and age play a role in affecting whole-cell and localized Ca2+ signaling, which are important to arterial vasoreactivity and cerebral blood flow.
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Affiliation(s)
- Casey Reid
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Monica Romero
- Advanced Imaging and Microscopy Core, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Stephanie B. Chang
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Noah Osman
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Jose L. Puglisi
- Department of Biostatistics, School of Medicine, California Northstate University, Elk Grove, CA, United States
| | - Christopher G. Wilson
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Arlin B. Blood
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Lubo Zhang
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
| | - Sean M. Wilson
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States
- Advanced Imaging and Microscopy Core, Loma Linda University School of Medicine, Loma Linda, CA, United States
- *Correspondence: Sean M. Wilson,
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Bobkov D, Semenova S. Impact of lipid rafts on transient receptor potential channel activities. J Cell Physiol 2022; 237:2034-2044. [PMID: 35014032 DOI: 10.1002/jcp.30679] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/06/2021] [Accepted: 12/23/2021] [Indexed: 11/06/2022]
Abstract
Members of the transient receptor potential (TRP) superfamily are cation channels that are expressed in nearly every mammalian cell type and respond as cellular sensors to various environmental stimuli. Light, pressure, osmolarity, temperature, and other stimuli can induce TRP calcium conductivity and correspondingly trigger many signaling processes in cells. Disruption of TRP channel activity, as a rule, harms cellular function. Despite numerous studies, the mechanisms of TRP channel regulation are not yet sufficiently clear, in part, because TRP channels are regulated by a broad set of ligands having diverse physical and chemical features. It is now known that some TRP members are located in membrane microdomains termed lipid rafts. Moreover, interaction between specific raft-associated lipids with channels may be a key regulation mechanism. This review examines recent findings related to the roles of lipid rafts in regulation of TRP channel activity. The mechanistic events of channel interactions with the main lipid raft constituent, cholesterol, are being clarified. Better understanding of mechanisms behind such interactions would help establish the key elements of TRP channel regulation and hence allow control of cellular responses to environmental stimuli.
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Affiliation(s)
- Danila Bobkov
- Laboratory of Ionic Mechanisms of Cell Signaling, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Svetlana Semenova
- Laboratory of Ionic Mechanisms of Cell Signaling, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
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Dixon RE, Navedo MF, Binder MD, Santana LF. Mechanisms and Physiological Implications of Cooperative Gating of Ion Channels Clusters. Physiol Rev 2021; 102:1159-1210. [PMID: 34927454 DOI: 10.1152/physrev.00022.2021] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ion channels play a central role in the regulation of nearly every cellular process. Dating back to the classic 1952 Hodgkin-Huxley model of the generation of the action potential, ion channels have always been thought of as independent agents. A myriad of recent experimental findings exploiting advances in electrophysiology, structural biology, and imaging techniques, however, have posed a serious challenge to this long-held axiom as several classes of ion channels appear to open and close in a coordinated, cooperative manner. Ion channel cooperativity ranges from variable-sized oligomeric cooperative gating in voltage-gated, dihydropyridine-sensitive Cav1.2 and Cav1.3 channels to obligatory dimeric assembly and gating of voltage-gated Nav1.5 channels. Potassium channels, transient receptor potential channels, hyperpolarization cyclic nucleotide-activated channels, ryanodine receptors (RyRs), and inositol trisphosphate receptors (IP3Rs) have also been shown to gate cooperatively. The implications of cooperative gating of these ion channels range from fine tuning excitation-contraction coupling in muscle cells to regulating cardiac function and vascular tone, to modulation of action potential and conduction velocity in neurons and cardiac cells, and to control of pace-making activity in the heart. In this review, we discuss the mechanisms leading to cooperative gating of ion channels, their physiological consequences and how alterations in cooperative gating of ion channels may induce a range of clinically significant pathologies.
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Affiliation(s)
- Rose Ellen Dixon
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, CA, United States
| | - Marc D Binder
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
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CCT4 suppression inhibits tumor growth in hepatocellular carcinoma by interacting with Cdc20. Chin Med J (Engl) 2021; 134:2721-2729. [PMID: 34732665 PMCID: PMC8631418 DOI: 10.1097/cm9.0000000000001851] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The chaperonin containing t-complex (CCT) proteins play an important role in cell cycle-related protein degradation in yeast and mammals. The role of the chaperonin containing t-complex 4 (CCT4), one subtype of CCT proteins, in the progress of hepatocellular carcinoma (HCC) was not fully elucidated. Here, we aimed to explore the mechanisms of CCT4 in HCC. METHODS In this study, we used the UALCAN platform to analyze the relationship between CCT4 and HCC, and the association of CCT4 with the overall survival (OS) of HCC patients was also analyzed. CCT4 expression in HCC tumor tissues and normal tissues was also determined by western blot (WB) assay. Lentivirus vector was used to knock down the CCT4 expression, and quantitative polymerase chain reaction and WB were used to determine the level of CCT4 in HCC cell lines. Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to detect the cell proliferation, and flow cytometry (FCM) was performed to evaluate the effect of CCT4 on the apoptosis of HCC cells. Co-immunoprecipitation (co-IP) assay and WB were used to explore the mechanisms of CCT4 regulating the growth of HCC. Data were calculated from at least three replicate experiments and expressed as mean ± standard deviation. Student's t test, paired t test, and Kaplan-Meier analysis were used to compare across different groups. RESULTS We found CCT4 was upregulated in HCC tissues compared with normal tissues, and its high expression was associated with poor prognosis (P < 0.001). CCT4 was significantly increased in HCC tumor tissues compared with normal tissues (0.98 ± 0.12 vs. 0.23 ± 0.05, t = 7.73, P < 0.001). After being transfected with CCT4 short-hairpin RNA (shRNA), CCT4 was decreased in mRNA level and protein level in both Huh7 (mRNA level: 0.41 ± 0.07 vs. 1.01 ± 0.11, t = 8.09, P = 0.001; protein level: 0.61 ± 0.03 vs. 0.93 ± 0.07, t = 7.19, P = 0.002) and Hep3b cells (mRNA level: 0.55 ± 0.11 vs. 1.04 ± 0.15, t = 4.51, P = 0.011; protein level: 0.64 ± 0.10 vs. 0.95 ± 0.08, t = 4.32, P = 0.012). CCK8 assay indicated that CCT4 knockdown inhibited cell proliferation in both Huh7 (OD value of 3 days: 0.60 ± 0.14 vs. 0.97 ± 0.16, t = 3.13, P = 0.036; OD value of 4 days: 1.03 ± 0.07 vs. 1.50 ± 0.12, t = 5.97, P = 0.004) and Hep3b (OD value of 3 days: 0.69 ± 0.14 vs. 1.10 ± 0.11, t = 3.91, P = 0.017; OD value of 4 days: 1.12 ± 0.12 vs. 1.48 ± 0.13, t = 3.55, P = 0.024) cells. EdU assay showed that CCT4 knockdown inhibited the cell proliferation in both Huh7 (EdU positive rate: [31.25 ± 3.41]% vs. [58.72 ± 3.78]%, t = 9.34, P = 0.001) and Hep3b cells (EdU positive rate: [44.13 ± 7.02]% vs. [61.79 ± 3.96]%, t = 3.79, P = 0.019). FCM assay suggested that CCT4 knockdown induced apoptosis in HCC cells (apoptosis rate of Huh7: [9.10 ± 0.80]% vs. [3.66 ± 0.64]%, t = -9.18, P = 0.001; apoptosis rate of Hep3b: [6.69 ± 0.72]% vs. [4.20 ± 0.86]%, t = -3.84, P = 0.018). We also found that CCT4 could regulate anaphase-promoting complex (APC)Cdc20 activity via interacting with Cdc20. Furthermore, CCT4 knockdown induced securin (0.65 ± 0.06 vs. 0.44 ± 0.05, t = -4.69, P = 0.009) and B-cell lymphoma-2 (Bcl-2) interacting mediator of cell death (Bim; 0.96 ± 0.06 vs. 0.61 ± 0.09, t = -5.65, P = 0.005) accumulation. The upregulation of securin inhibited cell growth by downregulating cyclin D1 (0.65 ± 0.05 vs. 1.04 ± 0.07, t = 8.12, P = 0.001), and the accumulation of Bim inhibited Bcl-2 (0.77 ± 0.04 vs. 0.87 ± 0.04, t = 3.00, P = 0.040) and activated caspase 9 (caspase 9: 0.77 ± 0.04 vs. 0.84 ± 0.05, t = 1.81, P = 0.145; cleaved caspase 9: 0.64 ± 0.06 vs. 0.16 ± 0.07, t = 1.81, P = 0.001), which led to elevated apoptosis. CONCLUSIONS Overall, these results showed that CCT4 played an important role in HCC pathogenesis through, at least partly, interacting with Cdc20.
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Lu T, Lee HC. Coronary Large Conductance Ca 2+-Activated K + Channel Dysfunction in Diabetes Mellitus. Front Physiol 2021; 12:750618. [PMID: 34744789 PMCID: PMC8567020 DOI: 10.3389/fphys.2021.750618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/14/2021] [Indexed: 11/24/2022] Open
Abstract
Diabetes mellitus (DM) is an independent risk of macrovascular and microvascular complications, while cardiovascular diseases remain a leading cause of death in both men and women with diabetes. Large conductance Ca2+-activated K+ (BK) channels are abundantly expressed in arteries and are the key ionic determinant of vascular tone and organ perfusion. It is well established that the downregulation of vascular BK channel function with reduced BK channel protein expression and altered intrinsic BK channel biophysical properties is associated with diabetic vasculopathy. Recent efforts also showed that diabetes-associated changes in signaling pathways and transcriptional factors contribute to the downregulation of BK channel expression. This manuscript will review our current understandings on the molecular, physiological, and biophysical mechanisms that underlie coronary BK channelopathy in diabetes mellitus.
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Affiliation(s)
- Tong Lu
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States
| | - Hon-Chi Lee
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States
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11
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Wang S, Ichinomiya T, Terada Y, Wang D, Patel HH, Head BP. Synapsin-Promoted Caveolin-1 Overexpression Maintains Mitochondrial Morphology and Function in PSAPP Alzheimer's Disease Mice. Cells 2021; 10:2487. [PMID: 34572135 PMCID: PMC8467690 DOI: 10.3390/cells10092487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 02/03/2023] Open
Abstract
Mitochondrial dysfunction plays a pivotal role in the Alzheimer's Disease (AD) pathology. Disrupted mitochondrial dynamics (i.e., fusion/fission balance), which are essential for normal mitochondria structure and function, are documented in AD. Caveolin-1 (Cav-1), a membrane/lipid raft (MLR) scaffolding protein regulates metabolic pathways in several different cell types such as hepatocytes and cancer cells. Previously, we have shown decreased expression of Cav-1 in the hippocampus of 9-month (m) old PSAPP mice, while hippocampal overexpression of neuron-targeted Cav-1 using the synapsin promoter (i.e., SynCav1) preserved cognitive function, neuronal morphology, and synaptic ultrastructure in 9 and 12 m PSAPP mice. Considering the central role of energy production in maintaining normal neuronal and synaptic function and survival, the present study reveals that PSAPP mice exhibit disrupted mitochondrial distribution, morphometry, and respiration. In contrast, SynCav1 mitigates mitochondrial damage and loss and enhances mitochondrial respiration. Furthermore, by examining mitochondrial dynamics, we found that PSAPP mice showed a significant increase in the phosphorylation of mitochondrial dynamin-related GTPase protein (DRP1), resulting in excessive mitochondria fragmentation and dysfunction. In contrast, hippocampal delivery of SynCav1 significantly decreased p-DRP1 and augmented the level of the mitochondrial fusion protein, mitofusin1 (Mfn1) in PSAPP mice, a molecular event, which may mechanistically explain for the preserved balance of mitochondria fission/fusion and metabolic resilience in 12 m PSAPP-SynCav1 mice. Our data demonstrate the critical role for Cav-1 in maintaining normal mitochondrial morphology and function through affecting mitochondrial dynamics and explain a molecular and cellular mechanism underlying the previously reported neuroprotective and cognitive preservation induced by SynCav1 in PSAPP mouse model of AD.
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Affiliation(s)
- Shanshan Wang
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Taiga Ichinomiya
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 8528501, Japan
| | - Yuki Terada
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
- Department of Anesthesiology, Nara Medical University, Kashihara 6348521, Japan
| | - Dongsheng Wang
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Hemal H. Patel
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Brian P. Head
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
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12
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Chang Y, Roy S, Pan Z. Store-Operated Calcium Channels as Drug Target in Gastroesophageal Cancers. Front Pharmacol 2021; 12:668730. [PMID: 34012400 PMCID: PMC8126661 DOI: 10.3389/fphar.2021.668730] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/12/2021] [Indexed: 12/24/2022] Open
Abstract
Gastroesophageal cancers, including tumors occurring in esophagus and stomach, usually have poor prognosis and lack effective chemotherapeutic drugs for treatment. The association between dysregulated store-operated calcium entry (SOCE), a key intracellular Ca2+ signaling pathway and gastroesophageal cancers are emerging. This review summarizes the recent advances in understanding the contribution of SOCE-mediated intracellular Ca2+ signaling to gastroesophageal cancers. It assesses the pathophysiological role of each component in SOCE machinery, such as Orais and STIMs in the cancer cell proliferation, migration, and invasion as well as stemness maintenance. Lastly, it discusses efforts towards development of more specific and potent SOCE inhibitors, which may be a new set of chemotherapeutic drugs appearing at the horizon, to provide either targeted therapy or adjuvant treatment to overcome drug resistance for gastroesophageal cancers.
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Affiliation(s)
- Yan Chang
- College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
| | - Souvik Roy
- Department of Mathematics, The University of Texas at Arlington, Arlington, TX, United States
| | - Zui Pan
- College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
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TRPC channel-derived calcium fluxes differentially regulate ATP and flow-induced activation of eNOS. Nitric Oxide 2021; 111-112:1-13. [PMID: 33813098 DOI: 10.1016/j.niox.2021.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 03/27/2021] [Indexed: 12/28/2022]
Abstract
Endothelial dysfunction, characterised by impaired nitric oxide (NO) bioavailability, arises in response to a variety of cardiovascular risk factors and precedes atherosclerosis. NO is produced by tight regulation of endothelial nitric oxide synthase (eNOS) activity in response to vasodilatory stimuli. This regulation of eNOS is mediated in part by store-operated calcium entry (SOCE). We hypothesized that both ATP- and flow-induced eNOS activation are regulated by SOCE derived from Orai1 channels and members of the transient receptor potential canonical (TRPC) channel family. Bovine aortic endothelial cells (BAECs) were pre-treated with pharmacological inhibitors of TRPC channels and Orai1 to examine their effect on calcium signaling and eNOS activation in response to flow and ATP. The peak and sustained ATP-induced calcium signal and the resulting eNOS activation were attenuated by inhibition of TRPC3, which we found to be store operated. TRPC4 blockade reduced the transient peak in calcium concentration following ATP stimulation, but did not significantly reduce eNOS activity. Simultaneous TRPC3 & 4 inhibition reduced flow-induced NO production via alterations in phosphorylation-mediated eNOS activity. Inhibition of TRPC1/6 or Orai1 failed to lower ATP-induced calcium entry or eNOS activation. Our results suggest that TRPC3 is a store-operated channel in BAECs and is the key regulator of ATP-induced eNOS activation, whereas flow stimulation also recruits TRPC4 into the pathway for the synthesis of NO.
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Shiratori-Hayashi M, Yamaguchi C, Eguchi K, Shiraishi Y, Kohno K, Mikoshiba K, Inoue K, Nishida M, Tsuda M. Astrocytic STAT3 activation and chronic itch require IP 3R1/TRPC-dependent Ca 2+ signals in mice. J Allergy Clin Immunol 2021; 147:1341-1353. [PMID: 32781002 DOI: 10.1016/j.jaci.2020.06.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 05/26/2020] [Accepted: 06/16/2020] [Indexed: 12/26/2022]
Abstract
BACKGROUND Chronic itch is a debilitating symptom of inflammatory skin diseases, but the underlying mechanism is poorly understood. We have recently demonstrated that astrocytes in the spinal dorsal horn become reactive in models of atopic and contact dermatitis via activation of the transcription factor signal transducer and activator of transcription 3 (STAT3) and critically contribute to chronic itch. In general, STAT3 is transiently activated; however, STAT3 activation in reactive astrocytes of chronic itch model mice persistently occurs via an unknown mechanism. OBJECTIVE We aimed to determine the mechanisms of persistent activation of astrocytic STAT3 in chronic itch conditions. METHODS To determine the factors that are required for persistent activation of astrocytic STAT3, Western blotting and calcium imaging with cultured astrocytes or spinal cord slices were performed. Thereafter, chronic itch model mice were used for genetic and behavioral experiments to confirm the role of the factors determined to mediate persistent STAT3 activation from in vitro and ex vivo experiments in chronic itch. RESULTS IP3 receptor type 1 (IP3R1) knockdown in astrocytes suppressed IL-6-induced persistent STAT3 activation and expression of lipocalin-2 (LCN2), an astrocytic STAT3-dependent inflammatory factor that is required for chronic itch. IP3R1-dependent astrocytic Ca2+ responses involved Ca2+ influx through the cation channel transient receptor potential canonical (TRPC), which was required for persistent STAT3 activation evoked by IL-6. IL-6 expression was upregulated in dorsal root ganglion neurons in a mouse model of chronic itch. Dorsal root ganglion neuron-specific IL-6 knockdown, spinal astrocyte-specific IP3R1 knockdown, and pharmacologic spinal TRPC inhibition attenuated LCN2 expression and chronic itch. CONCLUSION Our findings suggest that IP3R1/TRPC channel-mediated Ca2+ signals elicited by IL-6 in astrocytes are necessary for persistent STAT3 activation, LCN2 expression, and chronic itch, and they may also provide new targets for therapeutic intervention.
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Affiliation(s)
- Miho Shiratori-Hayashi
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Chiharu Yamaguchi
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Kazushi Eguchi
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Yuto Shiraishi
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Keita Kohno
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Katsuhiko Mikoshiba
- RIKEN Center for Biosystems Dynamics Research, Hyogo, Japan; Faculty of Science, Toho University, Chiba, Japan; Shanghai Institute of Immunochemical Studies, Shanghai Tech University, Shanghai, China
| | - Kazuhide Inoue
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Motohiro Nishida
- Department of Translational Pharmaceutical Sciences, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan; Division of Cardiocirculatory Signaling, National Institute for Physiological Sciences and Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Aichi, Japan
| | - Makoto Tsuda
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
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Li XP, Zhang J. Tongue sole (Cynoglossus semilaevis) interleukin 10 receptors are involved in the immune response against bacterial infection. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 115:103885. [PMID: 33045275 DOI: 10.1016/j.dci.2020.103885] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 10/06/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Interleukin (IL)-10, an immune-regulatory cytokine, exerts various biological functions through interaction with IL-10 receptors. In teleost, very limited functional studies on IL-10 receptors have been documented. In this study, we reported the expression patterns of IL-10 receptor 1 (CsIL-10R1) and receptor 2 (CsIL-10R2) of tongue sole (Cynoglossus semilaevis) and examined their biological properties. The expression of CsIL-10R1 and CsIL-10R2 occurred in multiple tissues and were regulated by bacterial challenge. In vitro binding studies showed that recombinant extracellular region of CsIL-10R1 (rCsIL-10R1ex) rather than rCsIL-10R2ex could bind with rCsIL-10. Cellular study showed that both CsIL-10R1 and CsIL-10R2 were expressed on peripheral blood leukocytes (PBLs), and blockade of CsIL-10R1 or CsIL-10R2 by antibody could reduce inhibitory effect of CsIL-10 on ROS production of PBLs. When injected in vivo, anti-rCsIL-10R1 or anti-rCsIL-10R2 antibody dramatically promoted the expression of proinflammatory cytokines and suppressed bacterial dissemination in tongue sole tissues. Consistently, the overexpression of CsIL-10R1 or CsIL-10R2 significantly enhanced bacterial dissemination, and the overexpression of CsIL-10R1M bearing STAT3 site mutation reduced bacterial dissemination. Overall, these results demonstrate for the first time teleost IL-10 receptors play a negative role in antibacterial immunity and add insight into the function of CsIL-10 receptors.
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Affiliation(s)
- Xue-Peng Li
- CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; School of Ocean, Yantai University, Yantai, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jian Zhang
- CAS Key Laboratory of Experimental Marine Biology, CAS Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; School of Ocean, Yantai University, Yantai, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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Gutorov R, Peters M, Katz B, Brandwine T, Barbera NA, Levitan I, Minke B. Modulation of Transient Receptor Potential C Channel Activity by Cholesterol. Front Pharmacol 2019; 10:1487. [PMID: 31920669 PMCID: PMC6923273 DOI: 10.3389/fphar.2019.01487] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/15/2019] [Indexed: 12/11/2022] Open
Abstract
Changes of cholesterol level in the plasma membrane of cells have been shown to modulate ion channel function. The proposed mechanisms underlying these modulations include association of cholesterol to a single binding site at a single channel conformation, association to a highly flexible cholesterol binding site adopting multiple poses, and perturbation of lipid rafts. These perturbations have been shown to induce reversible targeting of mammalian transient receptor potential C (TRPC) channels to the cholesterol-rich membrane environment of lipid rafts. Thus, the observed inhibition of TRPC channels by methyl-β-cyclodextrin (MβCD), which induces cholesterol efflux from the plasma membrane, may result from disruption of lipid rafts. This perturbation was also shown to disrupt multimolecular signaling complexes containing TRPC channels. The Drosophila TRP and TRP-like (TRPL) channels belong to the TRPC channel subfamily. When the Drosophila TRPL channel was expressed in S2 or HEK293 cells and perfused with MβCD, the TRPL current was abolished in less than 100 s, fitting well the fast kinetic phase of cholesterol sequestration experiments in cells. It was thus suggested that the fast kinetics of TRPL channel suppression by MβCD arise from disruption of lipid rafts. Accordingly, lipid raft perturbation by cholesterol sequestration could give clues to the function of lipid environment in TRPC channel activity and its mechanism.
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Affiliation(s)
- Rita Gutorov
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Maximilian Peters
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Ben Katz
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Tal Brandwine
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Nicolas A Barbera
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Irena Levitan
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Baruch Minke
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
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Ottolini M, Hong K, Sonkusare SK. Calcium signals that determine vascular resistance. WILEY INTERDISCIPLINARY REVIEWS. SYSTEMS BIOLOGY AND MEDICINE 2019; 11:e1448. [PMID: 30884210 PMCID: PMC6688910 DOI: 10.1002/wsbm.1448] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 02/07/2019] [Accepted: 02/14/2019] [Indexed: 12/19/2022]
Abstract
Small arteries in the body control vascular resistance, and therefore, blood pressure and blood flow. Endothelial and smooth muscle cells in the arterial walls respond to various stimuli by altering the vascular resistance on a moment to moment basis. Smooth muscle cells can directly influence arterial diameter by contracting or relaxing, whereas endothelial cells that line the inner walls of the arteries modulate the contractile state of surrounding smooth muscle cells. Cytosolic calcium is a key driver of endothelial and smooth muscle cell functions. Cytosolic calcium can be increased either by calcium release from intracellular stores through IP3 or ryanodine receptors, or the influx of extracellular calcium through ion channels at the cell membrane. Depending on the cell type, spatial localization, source of a calcium signal, and the calcium-sensitive target activated, a particular calcium signal can dilate or constrict the arteries. Calcium signals in the vasculature can be classified into several types based on their source, kinetics, and spatial and temporal properties. The calcium signaling mechanisms in smooth muscle and endothelial cells have been extensively studied in the native or freshly isolated cells, therefore, this review is limited to the discussions of studies in native or freshly isolated cells. This article is categorized under: Biological Mechanisms > Cell Signaling Laboratory Methods and Technologies > Imaging Models of Systems Properties and Processes > Mechanistic Models.
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Affiliation(s)
- Matteo Ottolini
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Pharmacology, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
| | - Kwangseok Hong
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Physical Education, Chung-Ang University, Seoul, 06974, South Korea
| | - Swapnil K. Sonkusare
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Pharmacology, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
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Evidence of selective activation of aryl hydrocarbon receptor nongenomic calcium signaling by pyrene. Biochem Pharmacol 2018; 158:1-12. [PMID: 30248327 DOI: 10.1016/j.bcp.2018.09.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 09/20/2018] [Indexed: 12/02/2022]
Abstract
In its classical genomic mode of action, the aryl hydrocarbon receptor (AhR) acts as a ligand activated transcription factor regulating expression of target genes such as CYP1A1 and CYP1B1. Some ligands may also trigger more rapid nongenomic responses through AhR, including calcium signaling (Ca2+). In the present study we observed that pyrene induced a relatively rapid increase in intracellular Ca2+-concentrations ([Ca2+]i) in human microvascular endothelial cells (HMEC-1) and human embryonic kidney cells (HEK293) that was attenuated by AhR-inhibitor treatment and/or transient AhR knockdown by RNAi. In silico molecular docking based on homology models, suggested that pyrene is not able to bind to the human AhR in the agonist conformation. Instead, pyrene docked in the antagonist conformation of the AhR PAS-B binding pocket, although the interaction differed from antagonists such as GNF-351 and CH223191. Accordingly, pyrene did not induce CYP1A1 or CYP1B1, but suppressed CYP1-expression by benzo[a]pyrene (B[a]P) in HMEC-1 cells, confirming that pyrene act as an antagonist of AhR-induced gene expression. Use of pharmacological inhibitors and Ca2+-free medium indicated that the pyrene-induced AhR nongenomic [Ca2+]i increase was initiated by Ca2+-release from intracellular stores followed by a later phase of extracellular Ca2+-influx, consistent with store operated calcium entry (SOCE). These effects was accompanied by an AhR-dependent reduction in ordered membrane lipid domains, as determined by di-4-ANEPPDHQ staining. Addition of cholesterol inhibited both the pyrene-induced [Ca2+]i-increase and alterations in membrane lipid order. In conclusion, we propose that pyrene binds to AhR, act as an antagonist of the canonical genomic AhR/Arnt/CYP1-pathway, reduces ordered membrane lipid domains, and activates AhR nongenomic Ca2+-signaling from intracellular stores.
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RIP3 dependent NLRP3 inflammasome activation is implicated in acute lung injury in mice. J Transl Med 2018; 16:233. [PMID: 30126430 PMCID: PMC6102827 DOI: 10.1186/s12967-018-1606-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 08/14/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND NLRP3 inflammasome is involved in the inflammatory responses during acute lung injury (ALI). RIP3 triggered NLRP3 inflammasome activation independent of necroptosis induction has recently been documented. In this study, the role of RIP3 in the activation of NLRP3 inflammasome in the development of ALI was investigated. METHODS A selective RIP3 inhibitor GSK872 was used to investigate the roles of RIP3 in NLRP3 inflammasome activation in the lipopolysaccharide (LPS) induced ALI mouse model. The mechanism of NLRP3 inflammasome activation was investigated in the human monocytic cell line THP-1. NLRP3 inflammasome and necroptosis were measured by flow cytometry or western blot. RIP3-NLRP3 interaction was interrogated using immunoprecipitation and the Duolink® In situ detection. RESULTS Significant upregulation of both necroptosis and NLRP3 inflammasome pathways were observed in the lungs of mice with LPS induced ALI. GSK872 significantly suppressed the activation of necroptosis and NLRP3 activation with reduction of IL-1β and IL-18 production and inflammatory cells infiltration, resulting in a significant amelioration of lung injury. These two processes were shown to be active in interstitial macrophages and CD11b+ monocyte-macrophages/dendritic cells. In THP-1 cells, RIP3 and NLRP3 interaction was enhanced by LPS/ATP stimulation resulting in IL-1β and IL-18 production. This RIP3-NLRP3 interaction was significantly inhibited by GSK872. CONCLUSION Taking together, these results show that RIP3 participates in the NLRP3 inflammasome activation in infiltrating macrophages in ALI induced by LPS. This process plays a significant pathogenic role in LPS-induced lung injury.
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Chen X, Shi C, Cao H, Chen L, Hou J, Xiang Z, Hu K, Han X. The hedgehog and Wnt/β-catenin system machinery mediate myofibroblast differentiation of LR-MSCs in pulmonary fibrogenesis. Cell Death Dis 2018; 9:639. [PMID: 29844390 PMCID: PMC5974360 DOI: 10.1038/s41419-018-0692-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/07/2018] [Indexed: 12/21/2022]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and fatal lung disease that is characterized by enhanced changes in stem cell differentiation and fibroblast proliferation. Resident mesenchymal stem cells (LR-MSCs) can undergo phenotype conversion to myofibroblasts to augment extracellular matrix production, impairing function and contributing to pulmonary fibrosis. Hedgehog and Wnt signaling are developmental signal cascades that play an essential role in regulating embryogenesis and tissue homeostasis. Recently, it has been reported that both hedgehog and Wnt signaling play important roles in pulmonary fibrogenesis. Thus, the identification of specific target regulators may yield new strategy for pulmonary fibrosis therapies. In our work, we demonstrated the critical role of Gli1, Wnt7b, Wnt10a and Fzd10 in the process of pulmonary fibrogenesis in vitro and in vivo. Gli1 was induced in LR-MSCs following TGF-β1 treatment and fibrotic lung tissues. Inhibition of Gli1 suppressed myofibroblast differentiation of LR-MSCs and pulmonary fibrosis, and decreased the expression of Wnt7b, Wnt10a and β-catenin. Gli1 bound to and increased promoter activity of the Wnt7b and Wnt10a genes, and Wnt7b and Wnt10a were critical activators of Wnt/β-catenin signaling. It was noteworthy that Fzd10 knockdown reduced Wnt7b and Wnt10a-induced activation of Wnt/β-catenin signaling, which imply that Wnt7b and Wnt10a may be the ligands for Fzd10. Moreover, siRNA-mediated inhibition of Fzd10 prevented TGF-β1-induced myofibroblast differentiation of LR-MSCs in vitro and impaired bleomycin-induced pulmonary fibrosis. We conclude that hedgehog and Wnt/β-catenin signaling play a critical role in promoting myofibroblast differentiation of LR-MSCs and development of pulmonary fibrosis. These findings elucidate a therapeutic approach to attenuate pulmonary fibrosis through targeted inhibition of Gli1 or Fzd10.
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Affiliation(s)
- Xiang Chen
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China
| | - Chaowen Shi
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China
| | - Honghui Cao
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China
| | - Ling Chen
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China
| | - Jiwei Hou
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China
| | - Zou Xiang
- Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Kebin Hu
- Department of Medicine, Division of Nephrology, Penn State University College of Medicine, Hershey, PA, 17033, USA
| | - Xiaodong Han
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, Jiangsu, 210093, China. .,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210093, China.
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21
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Pulli I, Lassila T, Pan G, Yan D, Olkkonen VM, Törnquist K. Oxysterol-binding protein related-proteins (ORPs) 5 and 8 regulate calcium signaling at specific cell compartments. Cell Calcium 2018; 72:62-69. [PMID: 29748134 DOI: 10.1016/j.ceca.2018.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/02/2018] [Accepted: 03/12/2018] [Indexed: 12/24/2022]
Abstract
Oxysterol-binding protein related-protein 5 and 8 (ORP5/8) localize to the membrane contact sites (MCS) of the endoplasmic reticulum (ER) and the mitochondria, as well as to the ER-plasma membrane (PM) MCS. The MCS are emerging as important regulators of cell signaling events, including calcium (Ca2+) signaling. ORP5/8 have been shown to interact with phosphatidylinositol-4,5-bisphosphate (PIP2) in the PM, and to modulate mitochondrial respiration and morphology. PIP2 is the direct precursor of inositol trisphosphate (IP3), a key second messenger responsible for Ca2+-release from the intracellular Ca2+ stores. Further, mitochondrial respiration is linked to Ca2+ transfer from the ER to the mitochondria. Hence, we asked whether ORP5/8 would affect Ca2+ signaling in these cell compartments, and employed genetically engineered aequorin Ca2+ probes to investigate the effect of ORP5/8 in the regulation of mitochondrial and caveolar Ca2+. Our results show that ORP5/8 overexpression leads to increased mitochondrial matrix Ca2+ as well as to increased Ca2+ concentration at the caveolar subdomains of the PM during histamine stimulation, while having no effect on the cytoplasmic Ca2+. Also, we found that ORP5/8 overexpression increases cell proliferation. Our results show that ORP5/8 regulate Ca2+ signaling at specific MCS foci. These local ORP5/8-mediated Ca2+ signaling events are likely to play roles in processes such as mitochondrial respiration and cell proliferation.
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Affiliation(s)
- Ilari Pulli
- Åbo Akademi University, Tykistökatu 6A, 20520 Turku, Finland
| | - Taru Lassila
- Åbo Akademi University, Tykistökatu 6A, 20520 Turku, Finland
| | - Guoping Pan
- The Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Daoguang Yan
- The Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Vesa M Olkkonen
- Minerva Foundation Institute For Medical Research, Biomedicum Helsinki, 00290 Helsinki, Finland; Department of Anatomy, Faculty of Medicine, FI-00014 University of Helsinki, Finland
| | - Kid Törnquist
- Åbo Akademi University, Tykistökatu 6A, 20520 Turku, Finland; Minerva Foundation Institute For Medical Research, Biomedicum Helsinki, 00290 Helsinki, Finland.
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Involvement of mGluR I in EphB/ephrinB reverse signaling activation induced retinal ganglion cell apoptosis in a rat chronic hypertension model. Brain Res 2018; 1683:27-35. [PMID: 29366625 DOI: 10.1016/j.brainres.2018.01.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/05/2018] [Accepted: 01/17/2018] [Indexed: 02/08/2023]
Abstract
EphB/ephrinB reverse signaling is involved in retinal ganglion cell (RGC) apoptosis in experimental glaucoma. Here, we further investigated the mechanisms underlying EphB/ephrinB reverse signaling activation induced RGC apoptosis in a rat chronic ocular hypertension (COH) model, using patch-clamp techniques in retinal slices. In COH retinas, RGCs showed higher spontaneous firing frequency and much more depolarized membrane potential as compared to control, which was mimicked by intravitreally injection of EphB2-Fc, an activator of ephrinB2. The changes in RGC spontaneous firing and membrane potential could be reversed by the tyrosine kinase inhibitor PP2, suggesting that EphB/ephrinB reverse signaling activation induced RGC hyperexcitability. Intravitreal pre-injection of either LY367385 or MPEP, selective mGluR1 and mGluR5 antagonists, also blocked the changes in RGC spontaneous firing and membrane potential. Co-immunoprecipitation experiments showed an interaction between ephrinB2 and group I metabotropic glutamate receptor (mGluR I) (mGluR1/mGluR5). Furthermore, intravitreal pre-injection of the mixture of L-NAME (an NO synthase inhibitor) and XPro1595 (a selective inhibitor of soluble TNF-α) could reduce the EphB2-Fc injection induced increase in RGC firing, suggesting that Müller cells might be involved in EphB/ephrinB reverse signaling activation induced change in RGC hyperexcitability. In addition, LY367385/MPEP reduced the numbers of TUNEL-positive RGCs both in EphB2-Fc injected and COH retinas. All results suggest that activation of EphB/ephrinB reverse signaling induces RGC hyperexcitability and apoptosis by interacting with mGluR I in COH rats. Appropriate reduction of EphB/ephrinB reverse signaling could alleviate the loss of RGCs in glaucoma.
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Kuntamallappanavar G, Dopico AM. BK β1 subunit-dependent facilitation of ethanol inhibition of BK current and cerebral artery constriction is mediated by the β1 transmembrane domain 2. Br J Pharmacol 2017; 174:4430-4448. [PMID: 28940182 DOI: 10.1111/bph.14046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Ethanol at concentrations obtained in the circulation during moderate-heavy episodic drinking (30-60 mM) causes cerebral artery constriction in several species, including humans. In rodents, ethanol-induced cerebral artery constriction results from ethanol inhibition of large conductance voltage/Ca2+i -gated K+ (BK) channels in cerebral artery myocytes. Moreover, the smooth muscle-abundant BK β1 accessory subunit is required for ethanol to inhibit cerebral artery myocyte BK channels under physiological Ca2+i and voltages and thus constrict cerebral arteries. The molecular bases of these ethanol actions remain unknown. Here, we set to identify the BK β1 region(s) that mediates ethanol-induced inhibition of cerebral artery myocyte BK channels and eventual arterial constriction. EXPERIMENTAL APPROACH We used protein biochemistry, patch-clamp on engineered channel subunits, reversible cDNA permeabilization of KCNMB1 K/O mouse arteries and artery in vitro pressurization. KEY RESULTS Ethanol inhibition of BK current was facilitated by β1 but not β4 subunits. Furthermore, only BK complexes containing β chimeras with β1 transmembrane (TM) domains on a β4 background or with a β1 TM2 domain on a β4 background displayed ethanol responses identical to those of BK complexes including wild-type β1. Moreover, β1 TM2 itself but not other β regions were necessary for ethanol-induced cerebral artery constriction. CONCLUSIONS AND IMPLICATIONS BK β1 TM2 is necessary for this subunit to enable ethanol-induced inhibition of myocyte BK channels and cerebral artery constriction at physiological Ca2+ and voltages. Thus, novel agents that target β1 TM2 may be considered to counteract ethanol-induced cerebral artery constriction and associated cerebrovascular conditions.
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Affiliation(s)
- Guruprasad Kuntamallappanavar
- Department of Pharmacology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Alex M Dopico
- Department of Pharmacology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
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Transient receptor potential canonical type 3 channels: Interactions, role and relevance - A vascular focus. Pharmacol Ther 2017; 174:79-96. [DOI: 10.1016/j.pharmthera.2017.02.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Tykocki NR, Boerman EM, Jackson WF. Smooth Muscle Ion Channels and Regulation of Vascular Tone in Resistance Arteries and Arterioles. Compr Physiol 2017; 7:485-581. [PMID: 28333380 DOI: 10.1002/cphy.c160011] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Vascular tone of resistance arteries and arterioles determines peripheral vascular resistance, contributing to the regulation of blood pressure and blood flow to, and within the body's tissues and organs. Ion channels in the plasma membrane and endoplasmic reticulum of vascular smooth muscle cells (SMCs) in these blood vessels importantly contribute to the regulation of intracellular Ca2+ concentration, the primary determinant of SMC contractile activity and vascular tone. Ion channels provide the main source of activator Ca2+ that determines vascular tone, and strongly contribute to setting and regulating membrane potential, which, in turn, regulates the open-state-probability of voltage gated Ca2+ channels (VGCCs), the primary source of Ca2+ in resistance artery and arteriolar SMCs. Ion channel function is also modulated by vasoconstrictors and vasodilators, contributing to all aspects of the regulation of vascular tone. This review will focus on the physiology of VGCCs, voltage-gated K+ (KV) channels, large-conductance Ca2+-activated K+ (BKCa) channels, strong-inward-rectifier K+ (KIR) channels, ATP-sensitive K+ (KATP) channels, ryanodine receptors (RyRs), inositol 1,4,5-trisphosphate receptors (IP3Rs), and a variety of transient receptor potential (TRP) channels that contribute to pressure-induced myogenic tone in resistance arteries and arterioles, the modulation of the function of these ion channels by vasoconstrictors and vasodilators, their role in the functional regulation of tissue blood flow and their dysfunction in diseases such as hypertension, obesity, and diabetes. © 2017 American Physiological Society. Compr Physiol 7:485-581, 2017.
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Affiliation(s)
- Nathan R Tykocki
- Department of Pharmacology, University of Vermont, Burlington, Vermont, USA
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
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Morales-Lázaro SL, Rosenbaum T. Multiple Mechanisms of Regulation of Transient Receptor Potential Ion Channels by Cholesterol. CURRENT TOPICS IN MEMBRANES 2017; 80:139-161. [DOI: 10.1016/bs.ctm.2017.05.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Wang Q, Leo MD, Narayanan D, Kuruvilla KP, Jaggar JH. Local coupling of TRPC6 to ANO1/TMEM16A channels in smooth muscle cells amplifies vasoconstriction in cerebral arteries. Am J Physiol Cell Physiol 2016; 310:C1001-9. [PMID: 27147559 DOI: 10.1152/ajpcell.00092.2016] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 04/28/2016] [Indexed: 11/22/2022]
Abstract
Anoctamin-1 [ANO1, also known as transmembrane protein 16A (TMEM16A)] is a Ca(2+)-activated Cl(-) channel expressed in arterial myocytes that regulates membrane potential and contractility. Signaling mechanisms that control ANO1 activity in arterial myocytes are poorly understood. In cerebral artery myocytes, ANO1 channels are activated by local Ca(2+) signals generated by plasma membrane nonselective cation channels, but the molecular identity of these proteins is unclear. Arterial myocytes express several different nonselective cation channels, including multiple members of the transient receptor potential receptor (TRP) family. The goal of this study was to identify localized ion channels that control ANO1 currents in cerebral artery myocytes. Coimmunoprecipitation and immunofluorescence resonance energy transfer microscopy experiments indicate that ANO1 and canonical TRP 6 (TRPC6) channels are present in the same macromolecular complex and localize in close spatial proximity in the myocyte plasma membrane. In contrast, ANO1 is not near TRPC3, TRP melastatin 4, or inositol trisphosphate receptor 1 channels. Hyp9, a selective TRPC6 channel activator, stimulated Cl(-) currents in myocytes that were blocked by T16Ainh-A01, an ANO1 inhibitor, ANO1 knockdown using siRNA, and equimolar replacement of intracellular EGTA with BAPTA, a fast Ca(2+) chelator that abolishes local Ca(2+) signaling. Hyp9 constricted pressurized cerebral arteries, and this response was attenuated by T16Ainh-A01. In contrast, T16Ainh-A01 did not alter depolarization-induced (60 mM K(+)) vasoconstriction. These data indicate that TRPC6 channels generate a local intracellular Ca(2+) signal that activates nearby ANO1 channels in myocytes to stimulate vasoconstriction.
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Affiliation(s)
- Qian Wang
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - M Dennis Leo
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Damodaran Narayanan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Korah P Kuruvilla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Jonathan H Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
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28
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Shin DM, Son A, Park S, Kim MS, Ahuja M, Muallem S. The TRPCs, Orais and STIMs in ER/PM Junctions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:47-66. [PMID: 27161224 DOI: 10.1007/978-3-319-26974-0_3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The Ca(2+) second messenger is initiated at ER/PM junctions and propagates into the cell interior to convey the receptor information. The signal is maintained by Ca(2+) influx across the plasma membrane through the Orai and TRPC channels. These Ca(2+) influx channels form complexes at ER/PM junctions with the ER Ca(2+) sensor STIM1, which activates the channels. The function of STIM1 is modulated by other STIM isoforms like STIM1L, STIM2 and STIM2.1/STIM2β and by SARAF, which mediates the Ca(2+)-dependent inhibition of Orai channels. The ER/PM junctions are formed at membrane contact sites by tethering proteins that generate several types of ER/PM junctions, such as PI(4,5)P2-poor and PI(4,5)P2-rich domains. This chapter discusses several properties of the TRPC channels, the Orai channels and the STIMs, their key interacting proteins and how interaction of the STIMs with the channels gates their activity. The chapter closes by highlighting open questions and potential future directions in this field.
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Affiliation(s)
- Dong Min Shin
- Department of Oral Biology, BK 21 PLUS Project, Yonsei University College of Dentistry, Seoul, 120-752, South Korea.
| | - Aran Son
- Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institute of Health, Bethesda, MD, 20892, USA
| | - Seonghee Park
- Department of Physiology, School of Medicine, EwhaWomans University, 911-1 Mok-6-dong, Yang Chun-gu, Seoul, 158-710, South Korea
| | - Min Seuk Kim
- Department of Oral Physiology, School of Dentistry, Wonkwang University, Iksan City, Jeonbuk, South Korea
| | - Malini Ahuja
- Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institute of Health, Bethesda, MD, 20892, USA
| | - Shmuel Muallem
- Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institute of Health, Bethesda, MD, 20892, USA.
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Protein Network Interacting with BK Channels. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2016; 128:127-61. [DOI: 10.1016/bs.irn.2016.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Constantin B. Role of Scaffolding Proteins in the Regulation of TRPC-Dependent Calcium Entry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:379-403. [PMID: 27161237 DOI: 10.1007/978-3-319-26974-0_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Plasma membrane ion channels, and in particular TRPC channels need a specific membrane environment and association with scaffolding, signaling, and cytoskeleton proteins in order to play their important functional role. The molecular composition of TRPC channels is an important factor in determining channel activation mechanisms. TRPC proteins are incorporated in macromolecular complexes including several key Ca(2 +) signaling proteins as well as proteins involved in vesicle trafficking, cytoskeletal interactions, and scaffolding. Evidence has been provided for association of TRPC with calmodulin (CaM), IP3R, PMCA, Gq/11, RhoA, and a variety of scaffolding proteins. The interaction between TRPC channels with adaptor proteins, determines their mode of regulation as well as their cellular localization and function. Adaptor proteins do not display any enzymatic activity but act as scaffold for the building of signaling complexes. The scaffolding proteins are involved in the assembling of these Ca(2+) signaling complexes, the correct sub-cellular localization of protein partners, and the regulation of the TRPC channelosome. In particular, these proteins, via their multiple protein-protein interaction motifs, can interact with various ion channels involved in the transmembrane potential, and membrane excitability. Scaffolding proteins are key components for the functional organization of TRPC channelosomes that serves as a platform regulating slow Ca(2+) entry, spatially and temporally controlled [Ca(2+)]i signals and Ca(2+) -dependent cellular functions.
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Affiliation(s)
- Bruno Constantin
- Laboratory STIM, ERL-7368 CNRS-Université de Poitiers, 1, rue Georges Bonnet, Bat. B36, Pôle Biologie-Santé, 86000, Poitiers, France.
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31
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Martinsen A, Dessy C, Morel N. Regulation of calcium channels in smooth muscle: new insights into the role of myosin light chain kinase. Channels (Austin) 2015; 8:402-13. [PMID: 25483583 DOI: 10.4161/19336950.2014.950537] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Smooth muscle myosin light chain kinase (MLCK) plays a crucial role in artery contraction, which regulates blood pressure and blood flow distribution. In addition to this role, MLCK contributes to Ca(2+) flux regulation in vascular smooth muscle (VSM) and in non-muscle cells, where cytoskeleton has been suggested to help Ca(2+) channels trafficking. This conclusion is based on the use of pharmacological inhibitors of MLCK and molecular and cellular techniques developed to down-regulate the enzyme. Dissimilarities have been observed between cells and whole tissues, as well as between large conductance and small resistance arteries. A differential expression in MLCK and ion channels (either voltage-dependent Ca(2+) channels or non-selective cationic channels) could account for these observations, and is in line with the functional properties of the arteries. A potential involvement of MLCK in the pathways modulating Ca(2+) entry in VSM is described in the present review.
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Key Words
- CaM, calmodulin
- ER, endoplasmic reticulum
- MLCK, myosin light chain kinase
- Myosin light chain kinase
- ROC, receptor-operated Ca2+ (channel)
- SMC, smooth muscle cell
- SOC, store-operated Ca2+ (channel)
- SR, sarcoplasmic reticulum
- TRP
- TRP, transient receptor potential (channel)
- VOC, voltage-operated Ca2+ (channel)
- VSM, vascular smooth muscle
- VSMC, vascular smooth muscle cell
- [Ca2+]cyt, cytosolic Ca2+ concentration
- siRNA, small interfering RNA
- vascular smooth muscle
- voltage-dependent calcium channels
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Affiliation(s)
- A Martinsen
- a Cell physiology; IoNS; UCLouvain ; Brussels , Belgium
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Markandeya YS, Phelan LJ, Woon MT, Keefe AM, Reynolds CR, August BK, Hacker TA, Roth DM, Patel HH, Balijepalli RC. Caveolin-3 Overexpression Attenuates Cardiac Hypertrophy via Inhibition of T-type Ca2+ Current Modulated by Protein Kinase Cα in Cardiomyocytes. J Biol Chem 2015; 290:22085-100. [PMID: 26170457 DOI: 10.1074/jbc.m115.674945] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Indexed: 12/24/2022] Open
Abstract
Pathological cardiac hypertrophy is characterized by subcellular remodeling of the ventricular myocyte with a reduction in the scaffolding protein caveolin-3 (Cav-3), altered Ca(2+) cycling, increased protein kinase C expression, and hyperactivation of calcineurin/nuclear factor of activated T cell (NFAT) signaling. However, the precise role of Cav-3 in the regulation of local Ca(2+) signaling in pathological cardiac hypertrophy is unclear. We used cardiac-specific Cav-3-overexpressing mice and in vivo and in vitro cardiac hypertrophy models to determine the essential requirement for Cav-3 expression in protection against pharmacologically and pressure overload-induced cardiac hypertrophy. Transverse aortic constriction and angiotensin-II (Ang-II) infusion in wild type (WT) mice resulted in cardiac hypertrophy characterized by significant reduction in fractional shortening, ejection fraction, and a reduced expression of Cav-3. In addition, association of PKCα and angiotensin-II receptor, type 1, with Cav-3 was disrupted in the hypertrophic ventricular myocytes. Whole cell patch clamp analysis demonstrated increased expression of T-type Ca(2+) current (ICa, T) in hypertrophic ventricular myocytes. In contrast, the Cav-3-overexpressing mice demonstrated protection from transverse aortic constriction or Ang-II-induced pathological hypertrophy with inhibition of ICa, T and intact Cav-3-associated macromolecular signaling complexes. siRNA-mediated knockdown of Cav-3 in the neonatal cardiomyocytes resulted in enhanced Ang-II stimulation of ICa, T mediated by PKCα, which caused nuclear translocation of NFAT. Overexpression of Cav-3 in neonatal myocytes prevented a PKCα-mediated increase in ICa, T and nuclear translocation of NFAT. In conclusion, we show that stable Cav-3 expression is essential for protecting the signaling mechanisms in pharmacologically and pressure overload-induced cardiac hypertrophy.
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Affiliation(s)
- Yogananda S Markandeya
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Laura J Phelan
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Marites T Woon
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Alexis M Keefe
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Courtney R Reynolds
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Benjamin K August
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - Timothy A Hacker
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706
| | - David M Roth
- the Veterans Affairs San Diego Healthcare Systems, San Diego, California 92161, and the Department of Anesthesiology, University of California at San Diego, La Jolla, California 92161
| | - Hemal H Patel
- the Veterans Affairs San Diego Healthcare Systems, San Diego, California 92161, and the Department of Anesthesiology, University of California at San Diego, La Jolla, California 92161
| | - Ravi C Balijepalli
- From the Cellular and Molecular Arrhythmia Research Program, Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706,
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Earley S, Brayden JE. Transient receptor potential channels in the vasculature. Physiol Rev 2015; 95:645-90. [PMID: 25834234 DOI: 10.1152/physrev.00026.2014] [Citation(s) in RCA: 291] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mammalian genome encodes 28 distinct members of the transient receptor potential (TRP) superfamily of cation channels, which exhibit varying degrees of selectivity for different ionic species. Multiple TRP channels are present in all cells and are involved in diverse aspects of cellular function, including sensory perception and signal transduction. Notably, TRP channels are involved in regulating vascular function and pathophysiology, the focus of this review. TRP channels in vascular smooth muscle cells participate in regulating contractility and proliferation, whereas endothelial TRP channel activity is an important contributor to endothelium-dependent vasodilation, vascular wall permeability, and angiogenesis. TRP channels are also present in perivascular sensory neurons and astrocytic endfeet proximal to cerebral arterioles, where they participate in the regulation of vascular tone. Almost all of these functions are mediated by changes in global intracellular Ca(2+) levels or subcellular Ca(2+) signaling events. In addition to directly mediating Ca(2+) entry, TRP channels influence intracellular Ca(2+) dynamics through membrane depolarization associated with the influx of cations or through receptor- or store-operated mechanisms. Dysregulation of TRP channels is associated with vascular-related pathologies, including hypertension, neointimal injury, ischemia-reperfusion injury, pulmonary edema, and neurogenic inflammation. In this review, we briefly consider general aspects of TRP channel biology and provide an in-depth discussion of the functions of TRP channels in vascular smooth muscle cells, endothelial cells, and perivascular cells under normal and pathophysiological conditions.
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Affiliation(s)
- Scott Earley
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
| | - Joseph E Brayden
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
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Steady-state modulation of voltage-gated K+ channels in rat arterial smooth muscle by cyclic AMP-dependent protein kinase and protein phosphatase 2B. PLoS One 2015; 10:e0121285. [PMID: 25793374 PMCID: PMC4368632 DOI: 10.1371/journal.pone.0121285] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 01/29/2015] [Indexed: 01/17/2023] Open
Abstract
Voltage-gated potassium channels (Kv) are important regulators of membrane potential in vascular smooth muscle cells, which is integral to controlling intracellular Ca2+ concentration and regulating vascular tone. Previous work indicates that Kv channels can be modulated by receptor-driven alterations of cyclic AMP-dependent protein kinase (PKA) activity. Here, we demonstrate that Kv channel activity is maintained by tonic activity of PKA. Whole-cell recording was used to assess the effect of manipulating PKA signalling on Kv and ATP-dependent K+ channels of rat mesenteric artery smooth muscle cells. Application of PKA inhibitors, KT5720 or H89, caused a significant inhibition of Kv currents. Tonic PKA-mediated activation of Kv appears maximal as application of isoprenaline (a β-adrenoceptor agonist) or dibutyryl-cAMP failed to enhance Kv currents. We also show that this modulation of Kv by PKA can be reversed by protein phosphatase 2B/calcineurin (PP2B). PKA-dependent inhibition of Kv by KT5720 can be abrogated by pre-treatment with the PP2B inhibitor cyclosporin A, or inclusion of a PP2B auto-inhibitory peptide in the pipette solution. Finally, we demonstrate that tonic PKA-mediated modulation of Kv requires intact caveolae. Pre-treatment of the cells with methyl-β-cyclodextrin to deplete cellular cholesterol, or adding caveolin-scaffolding domain peptide to the pipette solution to disrupt caveolae-dependent signalling each attenuated PKA-mediated modulation of the Kv current. These findings highlight a novel, caveolae-dependent, tonic modulatory role of PKA on Kv channels providing new insight into mechanisms and the potential for pharmacological manipulation of vascular tone.
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Antigny F, Konig S, Bernheim L, Frieden M. Inositol 1,4,5 trisphosphate receptor 1 is a key player of human myoblast differentiation. Cell Calcium 2014; 56:513-21. [PMID: 25468730 DOI: 10.1016/j.ceca.2014.10.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/17/2014] [Accepted: 10/27/2014] [Indexed: 11/18/2022]
Abstract
Cytosolic Ca(2+) signals are fundamental for the early and late steps of myoblast differentiation and are, as in many cells, generated by Ca(2+) release from internal stores as well as by plasma membrane Ca(2+) entry. Our recent studies identified the store-operated Ca(2+) channels, Orai1 and TRPC1&C4, as crucial for the early steps of human myogenesis and for the late fusion events. In the present work, we assessed the role of the inositol-1,4,5 tris-phosphate receptor (IP3R) type 1 during human myoblast differentiation. We demonstrated, using siRNA strategy that IP3R1 is required for the expression of muscle-specific transcription factors such as myogenin and MEF2 (myocyte enhancer factor 2), and for the formation of myotubes. The knockdown of IP3R1 strongly reduced endogenous spontaneous Ca(2+) transients, and attenuated store-operated Ca(2+) entry. As well, two Ca(2+)-dependent key enzymes of muscle differentiation, NFAT and CamKII are down-regulated upon siIP3R1 treatment. On the contrary, the overexpression of IP3R1 accelerated myoblasts differentiation. These findings identify Ca(2+) release mediated by IP3R1 as an essential mechanism during the early steps of myoblast differentiation.
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MESH Headings
- Calcium/physiology
- Calcium-Calmodulin-Dependent Protein Kinase Type 2/physiology
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cells, Cultured
- Humans
- Inositol 1,4,5-Trisphosphate Receptors/drug effects
- Inositol 1,4,5-Trisphosphate Receptors/genetics
- Inositol 1,4,5-Trisphosphate Receptors/physiology
- MEF2 Transcription Factors/physiology
- Myoblasts, Skeletal/cytology
- Myoblasts, Skeletal/physiology
- Myogenin/physiology
- NFATC Transcription Factors/physiology
- RNA, Small Interfering/pharmacology
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Affiliation(s)
- Fabrice Antigny
- Department of Basic Neurosciences, Geneva Medical Center, 1, Rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Stéphane Konig
- Department of Basic Neurosciences, Geneva Medical Center, 1, Rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Laurent Bernheim
- Department of Basic Neurosciences, Geneva Medical Center, 1, Rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Maud Frieden
- Department of Basic Neurosciences, Geneva Medical Center, 1, Rue Michel Servet, 1211 Geneva 4, Switzerland; Department of Cell Physiology and Metabolism, Geneva Medical Center, 1, Rue Michel Servet, 1211 Geneva 4, Switzerland.
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Rathor N, Chung HK, Wang SR, Wang JY, Turner DJ, Rao JN. Caveolin-1 enhances rapid mucosal restitution by activating TRPC1-mediated Ca2+ signaling. Physiol Rep 2014; 2:2/11/e12193. [PMID: 25367694 PMCID: PMC4255804 DOI: 10.14814/phy2.12193] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Early rapid mucosal restitution occurs as a consequence of epithelial cell migration to reseal superficial wounds, a process independent of cell proliferation. Our previous studies revealed that the canonical transient receptor potential-1 (TRPC1) functions as a store-operated Ca(2+) channel (SOCs) in intestinal epithelial cells (IECs) and regulates epithelial restitution after wounding, but the exact mechanism underlying TRPC1 activation remains elusive. Caveolin-1 (Cav1) is a major component protein that is associated with caveolar lipid rafts in the plasma membrane and was recently identified as a regulator of store-operated Ca(2+) entry (SOCE). Here, we showed that Cav1 plays an important role in the regulation of mucosal restitution by activating TRPC1-mediated Ca(2+) signaling. Target deletion of Cav1 delayed gastric mucosal repair after exposure to hypertonic NaCl in mice, although it did not affect total levels of TRPC1 protein. In cultured IECs, Cav1 directly interacted with TRPC1 and formed Cav1/TRPC1 complex as measured by immunoprecipitation assays. Cav1 silencing in stable TRPC1-transfected cells by transfection with siCav1 reduced SOCE without effect on the level of resting [Ca(2+)]cyt. Inhibition of Cav1 expression by siCav1 and subsequent decrease in Ca(2+) influx repressed epithelial restitution, as indicated by a decrease in cell migration over the wounded area, whereas stable ectopic overexpression of Cav1 increased Cav1/TRPC1 complex, induced SOCE, and enhanced cell migration after wounding. These results indicate that Cav1 physically interacts with and activates TRPC1, thus stimulating TRPC1-mediated Ca(2+) signaling and rapid mucosal restitution after injury.
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Affiliation(s)
- Navneeta Rathor
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA Baltimore VA Medical Center, Baltimore, Maryland, USA
| | - Hee K Chung
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA Baltimore VA Medical Center, Baltimore, Maryland, USA
| | - Shelley R Wang
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jian-Ying Wang
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA Baltimore VA Medical Center, Baltimore, Maryland, USA Department of Pathology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Douglas J Turner
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA Baltimore VA Medical Center, Baltimore, Maryland, USA
| | - Jaladanki N Rao
- Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland, USA Baltimore VA Medical Center, Baltimore, Maryland, USA
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Mathew R. Pulmonary hypertension and metabolic syndrome: Possible connection, PPARγ and Caveolin-1. World J Cardiol 2014; 6:692-705. [PMID: 25228949 PMCID: PMC4163699 DOI: 10.4330/wjc.v6.i8.692] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 04/29/2014] [Accepted: 06/27/2014] [Indexed: 02/06/2023] Open
Abstract
A number of disparate diseases can lead to pulmonary hypertension (PH), a serious disorder with a high morbidity and mortality rate. Recent studies suggest that the associated metabolic dysregulation may be an important factor adversely impacting the prognosis of PH. Furthermore, metabolic syndrome is associated with vascular diseases including PH. Inflammation plays a significant role both in PH and metabolic syndrome. Adipose tissue modulates lipid and glucose metabolism, and also produces pro- and anti-inflammatory adipokines that modulate vascular function and angiogenesis, suggesting a close functional relationship between the adipose tissue and the vasculature. Both caveolin-1, a cell membrane scaffolding protein and peroxisome proliferator-activated receptor (PPAR) γ, a ligand-activated transcription factor are abundantly expressed in the endothelial cells and adipocytes. Both caveolin-1 and PPARγ modulate proliferative and anti-apoptotic pathways, cell migration, inflammation, vascular homeostasis, and participate in lipid transport, triacylglyceride synthesis and glucose metabolism. Caveolin-1 and PPARγ regulate the production of adipokines and in turn are modulated by them. This review article summarizes the roles and inter-relationships of caveolin-1, PPARγ and adipokines in PH and metabolic syndrome.
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Guerrero-Hernandez A, Gallegos-Gomez ML, Sanchez-Vazquez VH, Lopez-Mendez MC. Acidic intracellular Ca(2+) stores and caveolae in Ca(2+) signaling and diabetes. Cell Calcium 2014; 56:323-31. [PMID: 25182518 DOI: 10.1016/j.ceca.2014.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 08/07/2014] [Indexed: 12/19/2022]
Abstract
Acidic Ca(2+) stores, particularly lysosomes, are newly discovered players in the well-orchestrated arena of Ca(2+) signaling and we are at the verge of understanding how lysosomes accumulate Ca(2+) and how they release it in response to different chemical, such as NAADP, and physical signals. Additionally, it is now clear that lysosomes play a key role in autophagy, a process that allows cells to recycle components or to eliminate damaged structures to ensure cellular well-being. Moreover, lysosomes are being unraveled as hubs that coordinate both anabolism via insulin signaling and catabolism via AMPK. These acidic vesicles have close contact with the ER and there is a bidirectional movement of information between these two organelles that exquisitely regulates cell survival. Lysosomes also connect with plasma membrane where caveolae are located as specialized regions involved in Ca(2+) and insulin signaling. Alterations of all these signaling pathways are at the core of insulin resistance and diabetes.
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Nilius B, Szallasi A. Transient Receptor Potential Channels as Drug Targets: From the Science of Basic Research to the Art of Medicine. Pharmacol Rev 2014; 66:676-814. [DOI: 10.1124/pr.113.008268] [Citation(s) in RCA: 348] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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de Souza LB, Ambudkar IS. Trafficking mechanisms and regulation of TRPC channels. Cell Calcium 2014; 56:43-50. [PMID: 25012489 DOI: 10.1016/j.ceca.2014.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 05/15/2014] [Accepted: 05/16/2014] [Indexed: 02/06/2023]
Abstract
TRPC channels are Ca(2+)-permeable cation channels which are regulated downstream from receptor-coupled PIP2 hydrolysis. These channels contribute to a wide variety of cellular functions. Loss or gain of channel function has been associated with dysfunction and aberrant physiology. TRPC channel functions are influenced by their physical and functional interactions with numerous proteins that determine their regulation, scaffolding, trafficking, as well as their effects on the downstream cellular processes. Such interactions also compartmentalize the Ca(2+) signals arising from TRPC channels. A large number of studies demonstrate that trafficking is a critical mode by which plasma membrane localization and surface expression of TRPC channels are regulated. This review will provide an overview of intracellular trafficking pathways as well as discuss the current state of knowledge regarding the mechanisms and components involved in trafficking of the seven members of the TRPC family (TRPC1-TRPC7).
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Affiliation(s)
- Lorena Brito de Souza
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, United States.
| | - Indu S Ambudkar
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, United States.
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Ablation of Akt2 protects against lipopolysaccharide-induced cardiac dysfunction: role of Akt ubiquitination E3 ligase TRAF6. J Mol Cell Cardiol 2014; 74:76-87. [PMID: 24805195 DOI: 10.1016/j.yjmcc.2014.04.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/08/2014] [Accepted: 04/22/2014] [Indexed: 01/03/2023]
Abstract
Lipopolysaccharide (LPS), an essential component of the outer membrane of Gram-negative bacteria, plays a pivotal role in myocardial anomalies in sepsis. Recent evidence has depicted a role of Akt in LPS-induced cardiac sequelae although little information is available with regard to the contribution of Akt isoforms in the endotoxin-induced cardiac dysfunction. This study examined the effect of Akt2 knockout on LPS-induced myocardial contractile dysfunction and the underlying mechanism(s) with a focus on TNF receptor-associated factor 6 (TRAF6). Echocardiographic properties and cardiomyocyte contractile function [peak shortening (PS), maximal velocity of shortening/relengthening, time-to-PS, time-to-90% relengthening] were examined in wild-type and Akt2 knockout mice following LPS challenge (4mg/kg, 4h). LPS challenge enlarged LV end systolic diameter, reduced fractional shortening and cardiomyocyte contractile capacity, prolonged TR90, promoted apoptosis, upregulated caspase-3/-12, ubiquitin, and the ubiquitination E3 ligase TRAF6 as well as decreased mitochondrial membrane potential without affecting the levels of TNF-α, toll-like receptor 4 and the mitochondrial protein ALDH2. Although Akt2 knockout failed to affect myocardial function, apoptosis, and ubiquitination, it significantly attenuated or mitigated LPS-induced changes in cardiac contractile and mitochondrial function, apoptosis and ubiquitination but not TRAF6. LPS facilitated ubiquitination, phosphorylation of Akt, GSK3β and p38, the effect of which with the exception of p38 was ablated by Akt2 knockout. TRAF6 inhibitory peptide or RNA silencing significantly attenuated LPS-induced Akt2 ubiquitination, cardiac contractile anomalies and apoptosis. These data collectively suggested that TRAF6 may play a pivotal role in mediating LPS-induced cardiac injury via Akt2 ubiquitination.
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Rathor N, Zhuang R, Wang JY, Donahue JM, Turner DJ, Rao JN. Src-mediated caveolin-1 phosphorylation regulates intestinal epithelial restitution by altering Ca(2+) influx after wounding. Am J Physiol Gastrointest Liver Physiol 2014; 306:G650-8. [PMID: 24557763 PMCID: PMC3989706 DOI: 10.1152/ajpgi.00003.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Early mucosal restitution occurs as a consequence of intestinal epithelial cell (IEC) migration to reseal superficial wounds, but its exact mechanism remains largely unknown. Caveolin-1 (Cav1), a major component associated with caveolar lipid rafts in the plasma membrane, is implicated in many aspects of cellular functions. This study determined if c-Src kinase (Src)-induced Cav1 phosphorylation promotes intestinal epithelial restitution after wounding by activating Cav1-mediated Ca(2+) signaling. Src directly interacted with Cav1, formed Cav1-Src complexes, and phosphorylated Cav1 in IECs. Inhibition of Src activity by its chemical inhibitor PP2 or suppression of the functional caveolin scaffolding domain by caveolin-scaffolding domain peptides prevented Cav1-Src interaction, reduced Cav1 phosphorylation, decreased Ca(2+) influx, and inhibited cell migration after wounding. Disruption of caveolar lipid raft microdomains by methyl-β-cyclodextrin reduced Cav1-mediated Ca(2+) influx and repressed epithelial restitution. Moreover, Src silencing prevented subcellular redistribution of phosphorylated Cav1 in migrating IECs. These results indicate that Src-induced Cav1 phosphorylation stimulates epithelial restitution by increasing Cav1-mediated Ca(2+) signaling after wounding, thus contributing to the maintenance of gut mucosal integrity under various pathological conditions.
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Affiliation(s)
- Navneeta Rathor
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and
| | - Ran Zhuang
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and
| | - Jian-Ying Wang
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and ,3Department of Pathology, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland
| | - James M. Donahue
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and
| | - Douglas J. Turner
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and
| | - Jaladanki N. Rao
- 1Department of Surgery, Cell Biology Group, University of Maryland School of Medicine, Baltimore, Maryland; ,2Baltimore Veterans Affairs Medical Center, Baltimore, Maryland; and
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Billaud M, Lohman AW, Johnstone SR, Biwer LA, Mutchler S, Isakson BE. Regulation of cellular communication by signaling microdomains in the blood vessel wall. Pharmacol Rev 2014; 66:513-69. [PMID: 24671377 DOI: 10.1124/pr.112.007351] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
It has become increasingly clear that the accumulation of proteins in specific regions of the plasma membrane can facilitate cellular communication. These regions, termed signaling microdomains, are found throughout the blood vessel wall where cellular communication, both within and between cell types, must be tightly regulated to maintain proper vascular function. We will define a cellular signaling microdomain and apply this definition to the plethora of means by which cellular communication has been hypothesized to occur in the blood vessel wall. To that end, we make a case for three broad areas of cellular communication where signaling microdomains could play an important role: 1) paracrine release of free radicals and gaseous molecules such as nitric oxide and reactive oxygen species; 2) role of ion channels including gap junctions and potassium channels, especially those associated with the endothelium-derived hyperpolarization mediated signaling, and lastly, 3) mechanism of exocytosis that has considerable oversight by signaling microdomains, especially those associated with the release of von Willebrand factor. When summed, we believe that it is clear that the organization and regulation of signaling microdomains is an essential component to vessel wall function.
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Affiliation(s)
- Marie Billaud
- Dept. of Molecular Physiology and Biophysics, University of Virginia School of Medicine, PO Box 801394, Charlottesville, VA 22902.
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Lipid rafts are required for signal transduction by angiotensin II receptor type 1 in neonatal glomerular mesangial cells. Exp Cell Res 2014; 324:92-104. [PMID: 24662198 DOI: 10.1016/j.yexcr.2014.03.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 03/10/2014] [Accepted: 03/13/2014] [Indexed: 11/24/2022]
Abstract
Angiotensin II (ANG-II) receptors (AGTRs) contribute to renal physiology and pathophysiology, but the underlying mechanisms that regulate AGTR function in glomerular mesangium are poorly understood. Here, we show that AGTR1 is the functional AGTR subtype expressed in neonatal pig glomerular mesangial cells (GMCs). Cyclodextrin (CDX)-mediated cholesterol depletion attenuated cell surface AGTR1 protein expression and ANG-II-induced intracellular Ca(2+) ([Ca(2+)]i) elevation in the cells. The COOH-terminus of porcine AGTR1 contains a caveolin (CAV)-binding motif. However, neonatal GMCs express CAV-1, but not CAV-2 and CAV-3. Colocalization and in situ proximity ligation assay detected an association between endogenous AGTR1 and CAV-1 in the cells. A synthetic peptide corresponding to the CAV-1 scaffolding domain (CSD) sequence also reduced ANG-II-induced [Ca(2+)]i elevation in the cells. Real-time imaging of cell growth revealed that ANG-II stimulates neonatal GMC proliferation. ANG-II-induced GMC growth was attenuated by EMD 66684, an AGTR1 antagonist; BAPTA, a [Ca(2+)]i chelator; KN-93, a Ca(2+)/calmodulin-dependent protein kinase II inhibitor; CDX; and a CSD peptide, but not PD 123319, a selective AGTR2 antagonist. Collectively, our data demonstrate [Ca(2+)]i-dependent proliferative effect of ANG-II and highlight a critical role for lipid raft microdomains in AGTR1-mediated signal transduction in neonatal GMCs.
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Mahavadi S, Bhattacharya S, Kumar DP, Clay C, Ross G, Akbarali HI, Grider JR, Murthy KS. Increased PDE5 activity and decreased Rho kinase and PKC activities in colonic muscle from caveolin-1-/- mice impair the peristaltic reflex and propulsion. Am J Physiol Gastrointest Liver Physiol 2013; 305:G964-74. [PMID: 24157969 PMCID: PMC3882438 DOI: 10.1152/ajpgi.00165.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Caveolae are specialized regions of the plasma membrane that concentrate receptors and associated signaling molecules critical in regulation of cellular response to transmitters and hormones. We have determined the effects of caveolin-1 (Cav-1) deletion, caveolin-1 siRNA, and caveolar disruption in mice on the signaling pathways that mediate contraction and relaxation in colonic smooth muscle and on the components of the peristaltic reflex in isolated tissue and propulsion in intact colonic segments. In Cav-1-/- mice, both relaxation and contraction were decreased in smooth muscle cells and muscle strips, as well as during both phases of the peristaltic reflex and colonic propulsion. The decrease in relaxation in response to the nitric oxide (NO) donor was accompanied by a decrease in cGMP levels and an increase in phosphodiesterase 5 (PDE5) activity. Relaxation by a PDE5-resistant cGMP analog was not affected in smooth muscle of Cav-1-/- mice, suggesting that inhibition of relaxation was due to augmentation of PDE5 activity. Similar effects on relaxation, PDE5 and cGMP were obtained in muscle cells upon disruption of caveolae by methyl-β-cyclodextrin or suppression of Cav-1. Sustained contraction mediated via inhibition of myosin light chain phosphatase (MLCP) activity is regulated by Rho kinase and PKC via phosphorylation of two endogenous inhibitors of MLCP: myosin phosphatase-targeting subunit (MYPT1) and 17-kDa PKC-potentiated protein phosphatase 1 inhibitor protein (CPI-17), respectively. The activity of both enzymes and phosphorylation of MYPT1 and CPI-17 were decreased in smooth muscle from Cav-1-/- mice. We conclude that the integrity of caveolae is essential for contractile and relaxant activity in colonic smooth muscle and the maintenance of neuromuscular function at organ level.
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Affiliation(s)
- Sunila Mahavadi
- Box 980551, Dept. of Physiology, School of Medicine, Virginia Commonwealth Univ., Richmond, VA 23298-0551.
| | | | | | | | | | - Hamid I. Akbarali
- Departments of 1Physiology and Biophysics, ,2Pharmacology and Toxicology, and ,3Medicine, and VCU Program in Enteric Neuromuscular Science (VPENS), School of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - John R. Grider
- Departments of 1Physiology and Biophysics, ,3Medicine, and VCU Program in Enteric Neuromuscular Science (VPENS), School of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - Karnam S. Murthy
- Departments of 1Physiology and Biophysics, ,3Medicine, and VCU Program in Enteric Neuromuscular Science (VPENS), School of Medicine, Virginia Commonwealth University, Richmond, Virginia
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Mathew R. Pathogenesis of pulmonary hypertension: a case for caveolin-1 and cell membrane integrity. Am J Physiol Heart Circ Physiol 2013; 306:H15-25. [PMID: 24163076 DOI: 10.1152/ajpheart.00266.2013] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pulmonary hypertension (PH) is a progressive disease with a high morbidity and mortality rate. Despite important advances in the field, the precise mechanisms leading to PH are not yet understood. Main features of PH are loss of vasodilatory response, the activation of proliferative and antiapoptotic pathways leading to pulmonary vascular remodeling and obstruction, elevated pressure and right ventricular hypertrophy, resulting in right ventricular failure and death. Experimental studies suggest that endothelial dysfunction may be the key underlying feature in PH. Caveolin-1, a major protein constituent of caveolae, interacts with several signaling molecules including the ones implicated in PH and modulates them. Disruption and progressive loss of endothelial caveolin-1 with reciprocal activation of proliferative pathways occur before the onset of PH, and the rescue of caveolin-1 inhibits proliferative pathways and attenuates PH. Extensive endothelial damage/loss occurs during the progression of the disease with subsequent enhanced expression of caveolin-1 in smooth muscle cells. This caveolin-1 in smooth muscle cells switches from being an antiproliferative factor to a proproliferative one and participates in cell proliferation and cell migration, possibly leading to irreversible PH. In contrast, the disruption of endothelial caveolin-1 is not observed in the hypoxia-induced PH, a reversible form of PH. However, proliferative pathways are activated in this model, indicating caveolin-1 dysfunction. Thus disruption or dysfunction of endothelial caveolin-1 leads to PH, and the status of caveolin-1 may determine the reversibility versus irreversibility of PH. This article reviews the role of caveolin-1 and cell membrane integrity in the pathogenesis and progression of PH.
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Affiliation(s)
- Rajamma Mathew
- Section of Pediatric Cardiology and Department of Physiology, Maria Fareri Children's Hospital/New York Medical College, Valhalla, New York
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Transient receptor potential canonical type 3 channels--their evolving role in hypertension and its related complications. J Cardiovasc Pharmacol 2013; 61:455-60. [PMID: 23364606 DOI: 10.1097/fjc.0b013e31828748a1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
: Recent studies indicate that transient receptor potential canonical type 3 (TRPC3) channels contribute to the regulation of blood pressure and vascular and renal function. Several studies show that TRPC3 dysfunction is associated with hypertension, atherosclerosis, cardiac hypertrophy, and cerebrovascular events. In this review, we summarize the role of TRPC3 channels in the cardiovascular system, and we focus on their pathophysiological role in hypertension and related target organ damages. We provide new insight into the involvement of TRPC3 channels in the development of hypertension and its related complications.
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48
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Senadheera S, Bertrand PP, Grayson TH, Leader L, Tare M, Murphy TV, Sandow SL. Enhanced contractility in pregnancy is associated with augmented TRPC3, L-type, and T-type voltage-dependent calcium channel function in rat uterine radial artery. Am J Physiol Regul Integr Comp Physiol 2013; 305:R917-26. [DOI: 10.1152/ajpregu.00225.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In pregnancy, α-adrenoceptor-mediated vasoconstriction is augmented in uterine radial arteries and is accompanied by underlying changes in smooth muscle (SM) Ca2+ activity. This study aims to determine the Ca2+ entry channels associated with altered vasoconstriction in pregnancy, with the hypothesis that augmented vasoconstriction involves transient receptor potential canonical type-3 (TRPC3) and L- and T-type voltage-dependent Ca2+ channels. Immunohistochemistry showed TRPC3, L-type Cav1.2 (as the α1C subunit), T-type Cav3.1 (α1G), and Cav3.2 (α1H) localization to the uterine radial artery SM. Fluorescence intensity of TRPC3, Cav1.2, and Cav3.2 was increased, and Cav3.1 decreased in radial artery SM from pregnant rats. Western blot analysis confirmed increased TRPC3 protein expression in the radial artery from pregnant rats. Pressure myography incorporating pharmacological intervention to examine the role of these channels in uterine radial arteries showed an attenuation of phenylephrine (PE)-induced constriction with Pyr3 {1-[4-[(2,3,3-trichloro-1-oxo-2-propen-1-yl)amino]phenyl]-5-(trifluoromethyl)-1 H-pyrazole-4-carboxylic acid}-mediated TRPC3 inhibition or with nifedipine-mediated L-type channel block alone in vessels from pregnant rats; both effects of which were diminished in radial arteries from nonpregnant rats. Combined TRPC3 and L-type inhibition attenuated PE-induced constriction in radial arteries, and the residual vasoconstriction was reduced and abolished with T-type channel block with NNC 55-0396 in arteries from nonpregnant and pregnant rats, respectively. With SM Ca2+ stores depleted and in the presence of PE, nifedipine, and NNC 55-0396, blockade of TRPC3 reversed PE-induced constriction. These data suggest that TRPC3 channels act synergistically with L- and T-type channels to modulate radial artery vasoconstriction, with the mechanism being augmented in pregnancy.
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Affiliation(s)
- Sevvandi Senadheera
- Department of Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Paul P. Bertrand
- Department of Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - T. Hilton Grayson
- Department of Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Leo Leader
- Leo Leader, School of Women's and Children's Health, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Marianne Tare
- Department of Physiology, Monash University, Melbourne, Australia; and
| | - Timothy V. Murphy
- Department of Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Shaun L. Sandow
- Department of Physiology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydoore, Australia
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Isshiki M, Nishimoto M, Mizuno R, Fujita T. FRET-based sensor analysis reveals caveolae are spatially distinct Ca2+ stores in endothelial cells. Cell Calcium 2013; 54:395-403. [PMID: 24120096 DOI: 10.1016/j.ceca.2013.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 09/17/2013] [Accepted: 09/18/2013] [Indexed: 01/01/2023]
Abstract
Ca2+-regulating and Ca2+-dependent molecules enriched in caveolae are typically shaped as plasmalemmal invaginations or vesicles. Caveolae structure and subcellular distribution are critical for Ca2+ release from endoplasmic reticulum Ca2+ stores and for Ca2+ influx from the extracellular space into the cell. However, Ca2+ dynamics inside caveolae have never been directly measured and remain uncharacterized. To target the fluorescence resonance energy transfer (FRET)-based Ca2+ sensing protein D1, a mutant of cameleon, to the intra-caveolar space, we made a cDNA construct encoding a chimeric protein of lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) and D1 (LOXD1). Immunofluorescence and immunoelectron microscopy confirmed that a significant portion of LOXD1 was localized with caveolin-1 at morphologically apparent caveolar vesicles in endothelial cells. LOXD1 detected ATP-induced transient Ca2+ decreases by confocal FRET imaging in the presence or absence of extracellular Ca2+. This ATP-induced Ca2+ decrease was abolished following knockdown of caveoin-1, suggesting an association with caveolae. The X-ray spectra obtained by the spot analysis of electron-opaque pyroantimonate precipitates further confirmed that ATP-induced calcium decreases in intra-caveolar vesicles. In conclusion, subplasmalemmal caveolae function as Ca2+-releasable Ca2+ stores in response to ATP. This intracellular local Ca2+ delivery system may contribute to the complex spatiotemporal organization of Ca2+ signaling.
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Affiliation(s)
- Masashi Isshiki
- Department of Molecular Vascular Endocrinology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan.
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Tamaki M, Fujitani Y, Hara A, Uchida T, Tamura Y, Takeno K, Kawaguchi M, Watanabe T, Ogihara T, Fukunaka A, Shimizu T, Mita T, Kanazawa A, Imaizumi MO, Abe T, Kiyonari H, Hojyo S, Fukada T, Kawauchi T, Nagamatsu S, Hirano T, Kawamori R, Watada H. The diabetes-susceptible gene SLC30A8/ZnT8 regulates hepatic insulin clearance. J Clin Invest 2013; 123:4513-24. [PMID: 24051378 DOI: 10.1172/jci68807] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 07/11/2013] [Indexed: 12/30/2022] Open
Abstract
Recent genome-wide association studies demonstrated that common variants of solute carrier family 30 member 8 gene (SLC30A8) increase susceptibility to type 2 diabetes. SLC30A8 encodes zinc transporter-8 (ZnT8), which delivers zinc ion from the cytoplasm into insulin granules. Although it is well known that insulin granules contain high amounts of zinc, the physiological role of secreted zinc remains elusive. In this study, we generated mice with β cell-specific Slc30a8 deficiency (ZnT8KO mice) and demonstrated an unexpected functional linkage between Slc30a8 deletion and hepatic insulin clearance. The ZnT8KO mice had low peripheral blood insulin levels, despite insulin hypersecretion from pancreatic β cells. We also demonstrated that a substantial amount of the hypersecreted insulin was degraded during its first passage through the liver. Consistent with these findings, ZnT8KO mice and human individuals carrying rs13266634, a major risk allele of SLC30A8, exhibited increased insulin clearance, as assessed by c-peptide/insulin ratio. Furthermore, we demonstrated that zinc secreted in concert with insulin suppressed hepatic insulin clearance by inhibiting clathrin-dependent insulin endocytosis. Our results indicate that SLC30A8 regulates hepatic insulin clearance and that genetic dysregulation of this system may play a role in the pathogenesis of type 2 diabetes.
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