1
|
Geisler SM, Ottaviani MM, Jacobo-Piqueras N, Theiner T, Mastrolia V, Guarina L, Ebner K, Obermair GJ, Carbone E, Tuluc P. Deletion of the α 2δ-1 calcium channel subunit increases excitability of mouse chromaffin cells. J Physiol 2024; 602:3793-3814. [PMID: 39004870 DOI: 10.1113/jp285681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 06/26/2024] [Indexed: 07/16/2024] Open
Abstract
High voltage-gated Ca2+ channels (HVCCs) shape the electrical activity and control hormone release in most endocrine cells. HVCCs are multi-subunit protein complexes formed by the pore-forming α1 and the auxiliary β, α2δ and γ subunits. Four genes code for the α2δ isoforms. At the mRNA level, mouse chromaffin cells (MCCs) express predominantly the CACNA2D1 gene coding for the α2δ-1 isoform. Here we show that α2δ-1 deletion led to ∼60% reduced HVCC Ca2+ influx with slower inactivation kinetics. Pharmacological dissection showed that HVCC composition remained similar in α2δ-1-/- MCCs compared to wild-type (WT), demonstrating that α2δ-1 exerts similar functional effects on all HVCC isoforms. Consistent with reduced HVCC Ca2+ influx, α2δ-1-/- MCCs showed reduced spontaneous electrical activity with action potentials (APs) having a shorter half-maximal duration caused by faster rising and decay slopes. However, the induced electrical activity showed opposite effects with α2δ-1-/- MCCs displaying significantly higher AP frequency in the tonic firing mode as well as an increase in the number of cells firing AP bursts compared to WT. This gain-of-function phenotype was caused by reduced functional activation of Ca2+-dependent K+ currents. Additionally, despite the reduced HVCC Ca2+ influx, the intracellular Ca2+ transients and vesicle exocytosis or endocytosis were unaltered in α2δ-1-/- MCCs compared to WT during sustained stimulation. In conclusion, our study shows that α2δ-1 genetic deletion reduces Ca2+ influx in cultured MCCs but leads to a paradoxical increase in catecholamine secretion due to increased excitability. KEY POINTS: Deletion of the α2δ-1 high voltage-gated Ca2+ channel (HVCC) subunit reduces mouse chromaffin cell (MCC) Ca2+ influx by ∼60% but causes a paradoxical increase in induced excitability. MCC intracellular Ca2+ transients are unaffected by the reduced HVCC Ca2+ influx. Deletion of α2δ-1 reduces the immediately releasable pool vesicle exocytosis but has no effect on catecholamine (CA) release in response to sustained stimuli. The increased electrical activity and CA release from MCCs might contribute to the previously reported cardiovascular phenotype of patients carrying α2δ-1 loss-of-function mutations.
Collapse
Affiliation(s)
- Stefanie M Geisler
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Matteo M Ottaviani
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Noelia Jacobo-Piqueras
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Tamara Theiner
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Vincenzo Mastrolia
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Laura Guarina
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Karl Ebner
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Gerald J Obermair
- Division of Physiology, Karl Landsteiner University of Health Sciences, Krems, Austria
| | - Emilio Carbone
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Petronel Tuluc
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
2
|
Yun SH, Mansurov V, Yang L, Yoon J, Leblanc N, Craviso GL, Zaklit J. Modulating Ca 2+ influx into adrenal chromaffin cells with short-duration nanosecond electric pulses. Biophys J 2024:S0006-3495(24)00418-1. [PMID: 38909279 DOI: 10.1016/j.bpj.2024.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 05/07/2024] [Accepted: 06/20/2024] [Indexed: 06/24/2024] Open
Abstract
Isolated bovine adrenal chromaffin cells exposed to single 2-, 4-, or 5-ns pulses undergo a rapid, transient rise in intracellular Ca2+ mediated by Ca2+ entry via voltage-gated Ca2+ channels (VGCCs), mimicking the activation of these cells in vivo by acetylcholine. However, pulse durations 150 ns or longer elicit larger amplitude and longer-lived Ca2+ responses due to Ca2+ influx via both VGCCs and a yet to be identified plasma membrane pathway(s). To further our understanding of the differential effects of ultrashort versus longer pulse durations on Ca2+ influx, chromaffin cells were loaded with calcium green-1 and exposed to single 3-, 5-, 11-, 25-, or 50-ns pulses applied at their respective Ca2+ activation threshold electric fields. Increasing pulse duration from 3 or 5 ns to only 11 ns was sufficient to elicit increased amplitude and longer-lived Ca2+ responses in the majority of cells, a trend that continued as pulse duration increased to 50 ns. The amplification of Ca2+ responses was not the result of Ca2+ release from intracellular stores and was accompanied by a decreased effectiveness of VGCC inhibitors to block the responses and a reduced reliance on extracellular Na+ and membrane depolarization to evoke the responses. Inhibitors of pannexin channels, P2X receptors, or non-selective cation channels failed to attenuate 50-ns-elicited Ca2+ responses, ruling out these Ca2+-permeable channels as secondary Ca2+ entry pathways. Analytical calculations and numerical modeling suggest that the parameter that best determines the response of chromaffin cells to increasing pulse durations is the time the membrane charges to its peak voltage. These results highlight the pronounced sensitivity of a neuroendocrine cell to pulse durations differing by only tens of nanoseconds, which has important implications for the future development of nanosecond pulse technologies enabling electrostimulation applications for spatially focused and graded in vivo neuromodulation.
Collapse
Affiliation(s)
- Sung Hae Yun
- Department of Electrical and Biomedical Engineering, College of Engineering, University of Nevada, Reno, Nevada
| | - Vasilii Mansurov
- Department of Electrical and Biomedical Engineering, College of Engineering, University of Nevada, Reno, Nevada
| | - Lisha Yang
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada
| | - Jihwan Yoon
- Department of Electrical and Biomedical Engineering, College of Engineering, University of Nevada, Reno, Nevada
| | - Normand Leblanc
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada
| | - Gale L Craviso
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada
| | - Josette Zaklit
- Department of Electrical and Biomedical Engineering, College of Engineering, University of Nevada, Reno, Nevada.
| |
Collapse
|
3
|
Weiss N, Zamponi GW. The T-type calcium channelosome. Pflugers Arch 2024; 476:163-177. [PMID: 38036777 DOI: 10.1007/s00424-023-02891-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 12/02/2023]
Abstract
T-type calcium channels perform crucial physiological roles across a wide spectrum of tissues, spanning both neuronal and non-neuronal system. For instance, they serve as pivotal regulators of neuronal excitability, contribute to cardiac pacemaking, and mediate the secretion of hormones. These functions significantly hinge upon the intricate interplay of T-type channels with interacting proteins that modulate their expression and function at the plasma membrane. In this review, we offer a panoramic exploration of the current knowledge surrounding these T-type channel interactors, and spotlight certain aspects of their potential for drug-based therapeutic intervention.
Collapse
Affiliation(s)
- Norbert Weiss
- Department of Pathophysiology, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
| | - Gerald W Zamponi
- Department of Clinical Neurosciences, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| |
Collapse
|
4
|
Maneu V, Borges R, Gandía L, García AG. Forty years of the adrenal chromaffin cell through ISCCB meetings around the world. Pflugers Arch 2023; 475:667-690. [PMID: 36884064 DOI: 10.1007/s00424-023-02793-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/20/2023] [Accepted: 01/28/2023] [Indexed: 03/09/2023]
Abstract
This historical review focuses on the evolution of the knowledge accumulated during the last two centuries on the biology of the adrenal medulla gland and its chromaffin cells (CCs). The review emerged in the context of a series of meetings that started on the Spanish island of Ibiza in 1982 with the name of the International Symposium on Chromaffin Cell Biology (ISCCB). Hence, the review is divided into two periods namely, before 1982 and from this year to 2022, when the 21st ISCCB meeting was just held in Hamburg, Germany. The first historical period extends back to 1852 when Albert Kölliker first described the fine structure and function of the adrenal medulla. Subsequently, the adrenal staining with chromate salts identified the CCs; this was followed by the establishment of the embryological origin of the adrenal medulla, and the identification of adrenaline-storing vesicles. By the end of the nineteenth century, the basic morphology, histochemistry, and embryology of the adrenal gland were known. The twentieth century began with breakthrough findings namely, the experiment of Elliott suggesting that adrenaline was the sympathetic neurotransmitter, the isolation of pure adrenaline, and the deciphering of its molecular structure and chemical synthesis in the laboratory. In the 1950s, Blaschko isolated the catecholamine-storing vesicles from adrenal medullary extracts. This switched the interest in CCs as models of sympathetic neurons with an explosion of studies concerning their functions, i.e., uptake of catecholamines by chromaffin vesicles through a specific coupled transport system; the identification of several vesicle components in addition to catecholamines including chromogranins, ATP, opioids, and other neuropeptides; the calcium-dependence of the release of catecholamines; the underlying mechanism of exocytosis of this release, as indicated by the co-release of proteins; the cross-talk between the adrenal cortex and the medulla; and the emission of neurite-like processes by CCs in culture, among other numerous findings. The 1980s began with the introduction of new high-resolution techniques such as patch-clamp, calcium probes, marine toxins-targeting ion channels and receptors, confocal microscopy, or amperometry. In this frame of technological advances at the Ibiza ISCCB meeting in 1982, 11 senior researchers in the field predicted a notable increase in our knowledge in the field of CCs and the adrenal medulla; this cumulative knowledge that occurred in the last 40 years of history of the CC is succinctly described in the second part of this historical review. It deals with cell excitability, ion channel currents, the exocytotic fusion pore, the handling of calcium ions by CCs, the kinetics of exocytosis and endocytosis, the exocytotic machinery, and the life cycle of secretory vesicles. These concepts together with studies on the dynamics of membrane fusion with super-resolution imaging techniques at the single-protein level were extensively reviewed by top scientists in the field at the 21st ISCCB meeting in Hamburg in the summer of 2022; this frontier topic is also briefly reviewed here. Many of the concepts arising from those studies contributed to our present understanding of synaptic transmission. This has been studied in physiological or pathophysiological conditions, in CCs from animal disease models. In conclusion, the lessons we have learned from CC biology as a peripheral model for brain and brain disease pertain more than ever to cutting-edge research in neurobiology. In the 22nd ISCCB meeting in Israel in 2024 that Uri Asheri is organizing, we will have the opportunity of seeing the progress of the questions posed in Ibiza, and on other questions that undoubtedly will arise.
Collapse
Affiliation(s)
- Victoria Maneu
- Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, Alicante, Spain
| | - Ricardo Borges
- Unidad de Farmacología, Departamento de Medicina Física y Farmacología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
| | - Luis Gandía
- Instituto Fundación Teófilo Hernando, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Instituto Fundación Teófilo Hernando, Madrid, Spain. .,Departamento de Farmacología y Terapéutica, Universidad Autónoma de Madrid, Madrid, Spain. .,Facultad de Medicina, Instituto de Investigación Sanitaria del Hospital Universitario La Princesa, Universidad Autónoma de Madrid, Madrid, Spain.
| |
Collapse
|
5
|
Marcantoni A, Chiantia G, Tomagra G, Hidisoglu E, Franchino C, Carabelli V, Carbone E. Two firing modes and well-resolved Na +, K +, and Ca 2+ currents at the cell-microelectrode junction of spontaneously active rat chromaffin cell on MEAs. Pflugers Arch 2023; 475:181-202. [PMID: 36260174 PMCID: PMC9849155 DOI: 10.1007/s00424-022-02761-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/23/2022] [Accepted: 10/07/2022] [Indexed: 02/01/2023]
Abstract
We recorded spontaneous extracellular action potentials (eAPs) from rat chromaffin cells (CCs) at 37 °C using microelectrode arrays (MEAs) and compared them with intracellularly recorded APs (iAPs) through conventional patch clamp recordings at 22 °C. We show the existence of two distinct firing modes on MEAs: a ~ 4 Hz irregular continuous firing and a frequent intermittent firing mode where periods of high-intraburst frequency (~ 8 Hz) of ~ 7 s duration are interrupted by silent periods of ~ 12 s. eAPs occurred either as negative- or positive-going signals depending on the contact between cell and microelectrode: either predominantly controlled by junction-membrane ion channels (negative-going) or capacitive/ohmic coupling (positive-going). Negative-going eAPs were found to represent the trajectory of the Na+, Ca2+, and K+ currents passing through the cell area in tight contact with the microelectrode during an AP (point-contact junction). The inward Nav component of eAPs was blocked by TTX in a dose-dependent manner (IC50 ~ 10 nM) while the outward component was strongly attenuated by the BK channel blocker paxilline (200 nM) or TEA (5 mM). The SK channel blocker apamin (200 nM) had no effect on eAPs. Inward Nav and Cav currents were well-resolved after block of Kv and BK channels or in cells showing no evident outward K+ currents. Unexpectedly, on the same type of cells, we could also resolve inward L-type currents after adding nifedipine (3 μM). In conclusion, MEAs provide a direct way to record different firing modes of rat CCs and to estimate the Na+, Ca2+, and K+ currents that sustain cell firing and spontaneous catecholamines secretion.
Collapse
Affiliation(s)
- Andrea Marcantoni
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| | - Giuseppe Chiantia
- grid.7605.40000 0001 2336 6580Department of Neuroscience, University of Torino, 10125 Turin, Italy
| | - Giulia Tomagra
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| | - Enis Hidisoglu
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| | - Claudio Franchino
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| | - Valentina Carabelli
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| | - Emilio Carbone
- grid.7605.40000 0001 2336 6580Department of Drug Science, Laboratory of Cell Physiology and Molecular Neuroscience, N.I.S. Centre, University of Torino, Corso Raffaello 30, 10125 Turin, Italy
| |
Collapse
|
6
|
Tamang HK, Yang R, Song Z, Hsu S, Peng C, Tung Y, Tzeng B, Chen C. Ca v 3.2 T-type calcium channel regulates mouse platelet activation and arterial thrombosis. J Thromb Haemost 2022; 20:1887-1899. [PMID: 35490411 PMCID: PMC9541131 DOI: 10.1111/jth.15745] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Cav 3.2 is a T-type calcium channel that causes low-threshold exocytosis. T-type calcium channel blockers reduce platelet granule exocytosis and aggregation. However, studies of the T-type calcium channel in platelets are lacking. OBJECTIVE To examine the expression and role of Cav 3.2 in platelet function. METHODS Global Cav 3.2-/- and platelet-specific Cav 3.2-/- mice and littermate controls were used for this study. Western blot analysis was used to detect the presence of Cav 3.2 and activation of the calcium-responsive protein extracellular signal-regulated kinase (ERK). Fura-2 dye was used to assess platelet calcium. Flow cytometry and light transmission aggregometry were used to evaluate platelet activation markers and aggregation, respectively. FeCl3 -induced thrombosis and a microfluidic flow device were used to assess in vivo and ex vivo thrombosis, respectively. RESULTS Cav 3.2 was expressed in mouse platelets. As compared with wild-type controls, Cav 3.2-/- mouse platelets showed reduced calcium influx. Similarly, treatment with the T-type calcium channel inhibitor Ni2+ decreased the calcium influx in wild-type platelets. As compared with controls, both Cav 3.2-/- and Ni2+ -treated wild-type platelets showed reduced activation of ERK. ATP release, P-selectin exposure, and αIIb β3 activation were reduced in Cav 3.2-/- and Ni2+ -treated wild-type platelets, as was platelet aggregation. On in vivo and ex vivo thrombosis assay, Cav3.2 deletion caused delayed thrombus formation. However, tail bleeding assay showed intact hemostasis. CONCLUSION These results suggest that Cav 3.2 is required for the optimal activation of platelets.
Collapse
Affiliation(s)
- Hem Kumar Tamang
- Taiwan International Graduate Program in Molecular MedicineNational Yang Ming Chiao Tung University and Academia SinicaTaipeiTaiwan
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| | - Ruey‐Bing Yang
- Taiwan International Graduate Program in Molecular MedicineNational Yang Ming Chiao Tung University and Academia SinicaTaipeiTaiwan
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| | - Zong‐Han Song
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| | - Shao‐Chun Hsu
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| | | | - Yi‐Chung Tung
- Research Center for Applied SciencesAcademia SinicaTaipeiTaiwan
| | - Bing‐Hsiean Tzeng
- Division of CardiologyFar Eastern Memorial Hospital and Tri‐Service General HospitalNational Defense Medical CenterTaipeiTaiwan
| | - Chien‐Chang Chen
- Taiwan International Graduate Program in Molecular MedicineNational Yang Ming Chiao Tung University and Academia SinicaTaipeiTaiwan
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| |
Collapse
|
7
|
Yue Q, Wang K, Guan M, Zhao Z, Li X, Yu P, Mao L. Single-Vesicle Electrochemistry Reveals Sex Difference in Vesicular Storage and Release of Catecholamine. Angew Chem Int Ed Engl 2022; 61:e202117596. [PMID: 35112448 DOI: 10.1002/anie.202117596] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Indexed: 12/17/2022]
Abstract
Quantitative measurements of sex difference in vesicle chemistry (i.e., chemical storage and release) at the single-vesicle level are essential to understand sex differences in cognitive behaviors; however, such measurements are very challenging to conventional analytical methods. By using single-vesicle electrochemistry, we find the duration of single exocytotic events of chromaffin cells prepared from male rats is statistically longer than that from female rats, leading to more neurotransmitter released in the male group. Further analysis reveals that a higher percentage of vesicles in the female group release part of the neurotransmitter, i.e., partial release, during exocytosis than that in male group. This sex dimorphism in neurotransmitter release in exocytosis might relate to the sex difference in the expression of voltage-dependent calcium channels and membrane lipid composition. Our finding offers the first experimental evidence that sex dimorphism even exists in vesicle chemistry, providing a brand new viewpoint for understanding the sex dimorphism in exocytosis.
Collapse
Affiliation(s)
- Qingwei Yue
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kai Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Ming Guan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xianchan Li
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Ping Yu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.,College of Chemistry, Beijing Normal University, Beijing, 100875, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| |
Collapse
|
8
|
Alterations of the Sympathoadrenal Axis Related to the Development of Alzheimer’s Disease in the 3xTg Mouse Model. BIOLOGY 2022; 11:biology11040511. [PMID: 35453710 PMCID: PMC9027376 DOI: 10.3390/biology11040511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 12/02/2022]
Abstract
Simple Summary Alzheimer’s disease (AD), the most common form of dementia, is becoming a global health problem and public health priority. In the advanced stages of AD, besides the initial cognitive symptoms, behavioral problems, particularly agitation and aggressiveness, become prevalent in AD patients. These non-cognitive symptoms could be related to alterations in the regulatory mechanism of the sympathetic nervous system. In this study, we used chromaffin cells (CCs) isolated from the adrenal gland of 3xTg (an AD mouse model) mice to characterize potential alterations in the regulation of the responses to stress mediated by the secretion of catecholamines. We compared these regulatory mechanisms in mice at two different ages: in 2-month-old mice, where no AD symptoms were observed, and in mice over 12 months of age, when AD-related cognitive impairment related was fully established. We found that the modulation of neurotransmitter release was stronger in CCs isolated from the adrenal medulla of 3xTg mice older than 12 months of age, an effect likely related to disease progression as it was not observed in CCs from age-matched wild-type (WT) mice. This enhanced modulation leads to an increased catecholamine release in response to stressful situations, which may explain the non-cognitive behavioral problems found in AD patients. Abstract Alzheimer’s disease (AD), the most common form of dementia, is becoming a global health problem and public health priority. In the advanced stages of AD, besides the initial cognitive symptoms, behavioral problems, particularly agitation and aggressiveness, become prevalent in AD patients. These non-cognitive symptoms could be related to a noradrenergic overactivation. In this study, we used chromaffin cells (CCs) isolated from the adrenal gland of 3xTg AD model mice to characterize potential alterations in the autocrine-paracrine modulation of voltage-dependent calcium channels (VDCCs), which in turn serve to regulate the release of catecholamines. We used mice at the presymptomatic stage (2 months) and mice over 12 months of age, when AD-related cognitive impairment was fully established. We found that the modulation of inward currents through VDCCs induced by extracellular ATP was stronger in CCs isolated from the adrenal medulla of 3xTg mice older than 12 months of age, an effect likely related to disease progression as it was not observed in CCs from age-matched WT mice. This enhanced modulation leads to increased catecholamine release in response to stressful situations, which may explain the non-cognitive behavioral problems found in AD patients.
Collapse
|
9
|
Cho H, Park HJ, Choi JH, Nam MH, Jeong JS, Seo YK. Sound affects the neuronal maturation of neuroblastoma cells and the repair of damaged tissues. ELECTRON J BIOTECHN 2022. [DOI: 10.1016/j.ejbt.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
10
|
Yue Q, Wang K, Guan M, Zhao Z, Li X, Yu P, Mao L. Single‐Vesicle Electrochemistry Reveals Sex Difference in Vesicular Storage and Release of Catecholamine. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202117596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Qingwei Yue
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Kai Wang
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Ming Guan
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xianchan Li
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Ping Yu
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- College of Chemistry Beijing Normal University Beijing 100875 China
- University of Chinese Academy of Sciences Beijing 100049 China
| |
Collapse
|
11
|
Gauberg J, Elkhatib W, Smith CL, Singh A, Senatore A. Divergent Ca 2+/calmodulin feedback regulation of Ca V1 and Ca V2 voltage-gated calcium channels evolved in the common ancestor of Placozoa and Bilateria. J Biol Chem 2022; 298:101741. [PMID: 35182524 PMCID: PMC8980814 DOI: 10.1016/j.jbc.2022.101741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 02/10/2022] [Accepted: 02/13/2022] [Indexed: 11/04/2022] Open
Abstract
CaV1 and CaV2 voltage-gated calcium channels evolved from an ancestral CaV1/2 channel via gene duplication somewhere near the stem animal lineage. The divergence of these channel types led to distinguishing functional properties that are conserved among vertebrates and bilaterian invertebrates and contribute to their unique cellular roles. One key difference pertains to their regulation by calmodulin (CaM), wherein bilaterian CaV1 channels are uniquely subject to pronounced, buffer-resistant Ca2+/CaM-dependent inactivation, permitting negative feedback regulation of calcium influx in response to local cytoplasmic Ca2+ rises. Early diverging, nonbilaterian invertebrates also possess CaV1 and CaV2 channels, but it is unclear whether they share these conserved functional features. The most divergent animals to possess both CaV1 and CaV2 channels are placozoans such as Trichoplax adhaerens, which separated from other animals over 600 million years ago shortly after their emergence. Hence, placozoans can provide important insights into the early evolution of CaV1 and CaV2 channels. Here, we build upon previous characterization of Trichoplax CaV channels by determining the cellular expression and ion-conducting properties of the CaV1 channel orthologue, TCaV1. We show that TCaV1 is expressed in neuroendocrine-like gland cells and contractile dorsal epithelial cells. In vitro, this channel conducts dihydropyridine-insensitive, high-voltage–activated Ca2+ currents with kinetics resembling those of rat CaV1.2 but with left-shifted voltage sensitivity for activation and inactivation. Interestingly, TCaV1, but not TCaV2, exhibits buffer-resistant Ca2+/CaM-dependent inactivation, indicating that this functional divergence evolved prior to the emergence of bilaterian animals and may have contributed to their unique adaptation for cytoplasmic Ca2+ signaling within various cellular contexts.
Collapse
Affiliation(s)
- Julia Gauberg
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - Wassim Elkhatib
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - Carolyn L Smith
- NINDS, National Institutes of Health, Bethesda Maryland, 20892 USA
| | - Anhadvir Singh
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - Adriano Senatore
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada.
| |
Collapse
|
12
|
Soucy JR, Burchett G, Brady R, Nichols K, Breault DT, Koppes AN, Koppes RA. Innervated adrenomedullary microphysiological system to model nicotine and opioid exposure. ORGANS-ON-A-CHIP 2021; 3:100009. [PMID: 38650595 PMCID: PMC11034938 DOI: 10.1016/j.ooc.2021.100009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Transition to extrauterine life results in a surge of catecholamines necessary for increased cardiovascular, respiratory, and metabolic activity. Mechanisms mediating adrenomedullary catecholamine release are poorly understood. Important mechanistic insight is provided by newborns delivered by cesarean section or subjected to prenatal nicotine or opioid exposure, demonstrating impaired release of adrenomedullary catecholamines. To investigate mechanisms regulating adrenomedullary innervation, we developed compartmentalized 3D microphysiological systems (MPS) by exploiting GelPins, capillary pressure barriers between cell-laden hydrogels. The MPS comprises discrete cultures of adrenal chromaffin cells and preganglionic sympathetic neurons within a contiguous bioengineered microtissue. Using this model, we demonstrate that adrenal chromaffin innervation plays a critical role in hypoxia-mediated catecholamine release. Opioids and nicotine were shown to affect adrenal chromaffin cell response to a reduced oxygen environment, but neurogenic control mechanisms remained intact. GelPin containing MPS represent an inexpensive and highly adaptable approach to study innervated organ systems and improve drug screening platforms.
Collapse
Affiliation(s)
| | | | - Ryan Brady
- Chemical Engineering, Northeastern University, Boston, MA, USA
| | - Kyla Nichols
- Chemical Engineering, Northeastern University, Boston, MA, USA
| | - David T. Breault
- Division of Endocrinology, Boston Children’s Hospital, Center for Life Sciences, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Abigail N. Koppes
- Chemical Engineering, Northeastern University, Boston, MA, USA
- Biology, Northeastern University, Boston, MA, USA
| | - Ryan A. Koppes
- Chemical Engineering, Northeastern University, Boston, MA, USA
| |
Collapse
|
13
|
El Ghaleb Y, Schneeberger PE, Fernández-Quintero ML, Geisler SM, Pelizzari S, Polstra AM, van Hagen JM, Denecke J, Campiglio M, Liedl KR, Stevens CA, Person RE, Rentas S, Marsh ED, Conlin LK, Tuluc P, Kutsche K, Flucher BE. CACNA1I gain-of-function mutations differentially affect channel gating and cause neurodevelopmental disorders. Brain 2021; 144:2092-2106. [PMID: 33704440 PMCID: PMC8422349 DOI: 10.1093/brain/awab101] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 12/11/2022] Open
Abstract
T-type calcium channels (Cav3.1 to Cav3.3) regulate low-threshold calcium spikes, burst firing and rhythmic oscillations of neurons and are involved in sensory processing, sleep, and hormone and neurotransmitter release. Here, we examined four heterozygous missense variants in CACNA1I, encoding the Cav3.3 channel, in patients with variable neurodevelopmental phenotypes. The p.(Ile860Met) variant, affecting a residue in the putative channel gate at the cytoplasmic end of the IIS6 segment, was identified in three family members with variable cognitive impairment. The de novo p.(Ile860Asn) variant, changing the same amino acid residue, was detected in a patient with severe developmental delay and seizures. In two additional individuals with global developmental delay, hypotonia, and epilepsy, the variants p.(Ile1306Thr) and p.(Met1425Ile), substituting residues at the cytoplasmic ends of IIIS5 and IIIS6, respectively, were found. Because structure modelling indicated that the amino acid substitutions differentially affect the mobility of the channel gate, we analysed possible effects on Cav3.3 channel function using patch-clamp analysis in HEK293T cells. The mutations resulted in slowed kinetics of current activation, inactivation, and deactivation, and in hyperpolarizing shifts of the voltage-dependence of activation and inactivation, with Cav3.3-I860N showing the strongest and Cav3.3-I860M the weakest effect. Structure modelling suggests that by introducing stabilizing hydrogen bonds the mutations slow the kinetics of the channel gate and cause the gain-of-function effect in Cav3.3 channels. The gating defects left-shifted and increased the window currents, resulting in increased calcium influx during repetitive action potentials and even at resting membrane potentials. Thus, calcium toxicity in neurons expressing the Cav3.3 variants is one likely cause of the neurodevelopmental phenotype. Computer modelling of thalamic reticular nuclei neurons indicated that the altered gating properties of the Cav3.3 disease variants lower the threshold and increase the duration and frequency of action potential firing. Expressing the Cav3.3-I860N/M mutants in mouse chromaffin cells shifted the mode of firing from low-threshold spikes and rebound burst firing with wild-type Cav3.3 to slow oscillations with Cav3.3-I860N and an intermediate firing mode with Cav3.3-I860M, respectively. Such neuronal hyper-excitability could explain seizures in the patient with the p.(Ile860Asn) mutation. Thus, our study implicates CACNA1I gain-of-function mutations in neurodevelopmental disorders, with a phenotypic spectrum ranging from borderline intellectual functioning to a severe neurodevelopmental disorder with epilepsy.
Collapse
Affiliation(s)
- Yousra El Ghaleb
- Institute of Physiology, Medical University Innsbruck, Innsbruck 6020, Austria
| | - Pauline E Schneeberger
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg 20251, Germany
| | - Monica L Fernández-Quintero
- Institute of Physiology, Medical University Innsbruck, Innsbruck 6020, Austria
- Institute of Theoretical Chemistry, University of Innsbruck, Innsbruck 6020, Austria
| | - Stefanie M Geisler
- Department of Pharmacology, University of Innsbruck, Innsbruck 6020, Austria
| | - Simone Pelizzari
- Institute of Physiology, Medical University Innsbruck, Innsbruck 6020, Austria
| | - Abeltje M Polstra
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, 1012 WX, The Netherlands
| | - Johanna M van Hagen
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, 1012 WX, The Netherlands
| | - Jonas Denecke
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg 20251, Germany
| | - Marta Campiglio
- Institute of Physiology, Medical University Innsbruck, Innsbruck 6020, Austria
| | - Klaus R Liedl
- Institute of Theoretical Chemistry, University of Innsbruck, Innsbruck 6020, Austria
| | - Cathy A Stevens
- Department of Pediatrics, University of Tennessee College of Medicine, Chattanooga, TN 37403, USA
| | | | - Stefan Rentas
- Division of Genomic Diagnostics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Eric D Marsh
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Laura K Conlin
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Petronel Tuluc
- Department of Pharmacology, University of Innsbruck, Innsbruck 6020, Austria
| | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg 20251, Germany
| | - Bernhard E Flucher
- Institute of Physiology, Medical University Innsbruck, Innsbruck 6020, Austria
| |
Collapse
|
14
|
Martínez-Ramírez C, Gil-Gómez I, G de Diego AM, García AG. Acute reversible SERCA blockade facilitates or blocks exocytosis, respectively in mouse or bovine chromaffin cells. Pflugers Arch 2021; 473:273-286. [PMID: 33108514 DOI: 10.1007/s00424-020-02483-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/03/2020] [Accepted: 10/20/2020] [Indexed: 11/29/2022]
Abstract
Pre-blockade of the sarco-endoplasmic reticulum (ER) calcium ATPase (SERCA) with irreversible thapsigargin depresses exocytosis in adrenal bovine chromaffin cells (BCCs). Distinct expression of voltage-dependent Ca2+-channel subtypes and of the Ca2+-induced Ca2+ release (CICR) mechanism in BCCs versus mouse chromaffin cells (MCCs) has been described. We present a parallel study on the effects of the acute SERCA blockade with reversible cyclopizonic acid (CPA), to repeated pulsing with acetylcholine (ACh) at short (15 s) and long intervals (60 s) at 37 °C, allowing the monitoring of the initial size of a ready-release vesicle pool (RRP) and its depletion and recovery in subsequent stimuli. We found (i) strong depression of exocytosis upon ACh pulsing at 15-s intervals and slower depression at 60-s intervals in both cell types; (ii) facilitation of exocytosis upon acute SERCA inhibition, with back to depression upon CPA washout in MCCs; (iii) blockade of exocytosis upon acute SERCA inhibition and pronounced rebound of exocytosis upon CPA washout in BCCs; (iv) basal [Ca2+]c elevation upon stimulation with ACh at short intervals (but not at long intervals) in both cell types; and (v) augmentation of basal [Ca2+]c and inhibition of peak [Ca2+]c amplitude upon CPA treatment in both cell types, with milder effects upon stimulation at 60-s intervals. These results are compatible with the view that while in MCCs the uptake of Ca2+ via SERCA contributes to the mitigation of physiological ACh triggered secretion, in BCCs the uptake of Ca2+ into the ER facilitates such responses likely potentiating a Ca2+-induced Ca2+ release mechanism. These drastic differences in the regulation of ACh-triggered secretion at 37 °C may help to understand different patterns of the regulation of exocytosis by the circulation of Ca2+ at a functional ER Ca2+ store.
Collapse
Affiliation(s)
- Carmen Martínez-Ramírez
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
- Fundación Teófilo Hernando, Parque científico de Madrid, Madrid, Spain
| | - Irene Gil-Gómez
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
- Fundación Teófilo Hernando, Parque científico de Madrid, Madrid, Spain
| | - Antonio M G de Diego
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain.
- Departamento de Farmacología, Universidad Autónoma de Madrid, Madrid, Spain.
- Fundación Teófilo Hernando, Parque científico de Madrid, Madrid, Spain.
- Instituto de Investigación Sanitaria del Hospital de La Princesa, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.
- DNS Neuroscience, Instituto Teófilo Hernando, Department of Pharmacology, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Antonio G García
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
- Fundación Teófilo Hernando, Parque científico de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital de La Princesa, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- DNS Neuroscience, Instituto Teófilo Hernando, Department of Pharmacology, Universidad Autónoma de Madrid, Madrid, Spain
| |
Collapse
|
15
|
|
16
|
Yang L, Fomina AF. Ca 2+ influx and clearance at hyperpolarized membrane potentials modulate spontaneous and stimulated exocytosis in neuroendocrine cells. Cell Calcium 2020; 87:102184. [PMID: 32151786 DOI: 10.1016/j.ceca.2020.102184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/10/2020] [Accepted: 02/21/2020] [Indexed: 01/09/2023]
Abstract
Neuroendocrine adrenal chromaffin cells release neurohormones catecholamines in response to Ca2+ entry via voltage-gated Ca2+ channels (VGCCs). Adrenal chromaffin cells also express non-voltage-gated channels, which may conduct Ca2+ at negative membrane potentials, whose role in regulation of exocytosis is poorly understood. We explored how modulation of Ca2+ influx at negative membrane potentials affects basal cytosolic Ca2+ concentration ([Ca2+]i) and exocytosis in metabolically intact voltage-clamped bovine adrenal chromaffin cells. We found that in these cells, Ca2+ entry at negative membrane potentials is balanced by Ca2+ extrusion by the Na+/Ca2+ exchanger and that this balance can be altered by membrane hyperpolarization or stimulation with an inflammatory hormone bradykinin. Membrane hyperpolarization or application of bradykinin augmented Ca2+-carrying current at negative membrane potentials, elevated basal [Ca2+]i, and facilitated synchronous exocytosis evoked by the small amounts of Ca2+ injected into the cell via VGCCs (up to 20 pC). Exocytotic responses evoked by the injections of the larger amounts of Ca2+ via VGCCs (> 20 pC) were suppressed by preceding hyperpolarization. In the absence of Ca2+ entry via VGCCs and Ca2+ extrusion via the Na+/Ca2+ exchanger, membrane hyperpolarization induced a significant elevation in [Ca2+]i and asynchronous exocytosis. Our results indicate that physiological interferences, such as membrane hyperpolarization and/or activation of non-voltage-gated Ca2+ channels, modulate basal [Ca2+]i and, consequently, segregation of exocytotic vesicles and their readiness to be released spontaneously and in response to Ca2+ entry via VGCCs. These mechanisms may play role in homeostatic plasticity of neuronal and endocrine cells.
Collapse
Affiliation(s)
- Lukun Yang
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, CA, 95616, USA; Department of Anesthesiology, The 5th Affiliated Hospital of SUN YAT-SEN University, Zhuhai, 519000, China.
| | - Alla F Fomina
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, CA, 95616, USA.
| |
Collapse
|
17
|
Hone AJ, Rueda-Ruzafa L, Gordon TJ, Gajewiak J, Christensen S, Dyhring T, Albillos A, McIntosh JM. Expression of α3β2β4 nicotinic acetylcholine receptors by rat adrenal chromaffin cells determined using novel conopeptide antagonists. J Neurochem 2020; 154:158-176. [PMID: 31967330 DOI: 10.1111/jnc.14966] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/17/2019] [Accepted: 01/13/2020] [Indexed: 01/07/2023]
Abstract
Adrenal chromaffin cells release neurotransmitters in response to stress and may be involved in conditions such as post-traumatic stress and anxiety disorders. Neurotransmitter release is triggered, in part, by activation of nicotinic acetylcholine receptors (nAChRs). However, despite decades of use as a model system for studying exocytosis, the nAChR subtypes involved have not been pharmacologically identified. Quantitative real-time PCR of rat adrenal medulla revealed an abundance of mRNAs for α3, α7, β2, and β4 subunits. Whole-cell patch-clamp electrophysiology of chromaffin cells and subtype-selective ligands were used to probe for nAChRs derived from the mRNAs found in adrenal medulla. A novel conopeptide antagonist, PeIA-5469, was created that is highly selective for α3β2 over other nAChR subtypes heterologously expressed in Xenopus laevis oocytes. Experiments using PeIA-5469 and the α3β4-selective α-conotoxin TxID revealed that rat adrenal medulla contain two populations of chromaffin cells that express either α3β4 nAChRs alone or α3β4 together with the α3β2β4 subtype. Conclusions were derived from observations that acetylcholine-gated currents in some cells were sensitive to inhibition by PeIA-5469 and TxID, while in other cells, currents were sensitive only to TxID. Expression of functional α7 nAChRs was determined using three α7-selective ligands: the agonist PNU282987, the positive allosteric modulator PNU120596, and the antagonist α-conotoxin [V11L,V16D]ArIB. The results of these studies identify for the first time the expression of α3β2β4 nAChRs as well as functional α7 nAChRs by rat adrenal chromaffin cells.
Collapse
Affiliation(s)
- Arik J Hone
- George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,School of Biological Sciences and University of Utah, Salt Lake City, Utah, USA.,Departament of Pharmacology and Therapeutics, Universidad Autónoma de Madrid, Madrid, Spain
| | - Lola Rueda-Ruzafa
- Departament of Pharmacology and Therapeutics, Universidad Autónoma de Madrid, Madrid, Spain.,Biomedical Research Center (CINBIO), University of Vigo, Vigo, Spain
| | - Thomas J Gordon
- School of Biological Sciences and University of Utah, Salt Lake City, Utah, USA
| | - Joanna Gajewiak
- School of Biological Sciences and University of Utah, Salt Lake City, Utah, USA
| | - Sean Christensen
- School of Biological Sciences and University of Utah, Salt Lake City, Utah, USA
| | | | - Almudena Albillos
- Departament of Pharmacology and Therapeutics, Universidad Autónoma de Madrid, Madrid, Spain
| | - J Michael McIntosh
- George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,School of Biological Sciences and University of Utah, Salt Lake City, Utah, USA.,Department of Psychiatry, University of Utah, Salt Lake City, Utah, USA
| |
Collapse
|
18
|
Carbone E, Borges R, Eiden LE, García AG, Hernández‐Cruz A. Chromaffin Cells of the Adrenal Medulla: Physiology, Pharmacology, and Disease. Compr Physiol 2019; 9:1443-1502. [DOI: 10.1002/cphy.c190003] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
19
|
de Pascual R, Álvarez-Ortego N, de Los Ríos C, Jacob-Mazariego G, García AG. Tetrabenazine Facilitates Exocytosis by Enhancing Calcium-Induced Calcium Release through Ryanodine Receptors. J Pharmacol Exp Ther 2019; 371:219-230. [PMID: 31209099 DOI: 10.1124/jpet.119.256560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/04/2019] [Indexed: 11/22/2022] Open
Abstract
Vesicular monoamine transporter-2 is expressed in the presynaptic secretory vesicles membrane in the brain. Its blockade by tetrabenazine (TBZ) causes depletion of dopamine at striatal basal ganglia; this is the mechanism underlying its long-standing use in the treatment of Huntington's disease. In the frame of a project aimed at investigating the kinetics of exocytosis from vesicles with partial emptying of their neurotransmitter, we unexpectedly found that TBZ facilitates exocytosis; thus, we decided to characterize such effect. We used bovine chromaffin cells (BCCs) challenged with repeated pulses of high K+ Upon repeated K+ pulsing, the exocytotic catecholamine release responses were gradually decaying. However, when cells were exposed to TBZ, responses were mildly augmented and decay rate delayed. Facilitation of exocytosis was not due to Ca2+ entry blockade through voltage-activated calcium channels (VACCs) because, in fact, TBZ mildly blocked the whole-cell Ca2+ current. However, TBZ mimicked the facilitatory effects of exocytosis elicited by BayK8644 (L-subtype VACC agonist), an effect blocked by nifedipine (VACC antagonist). On the basis that TBZ augmented the secretory responses to caffeine (but not those of histamine), we monitored its effects on cytosolic Ca2+ elevations ([Ca2+]c) triggered by caffeine or histamine. While the responses to caffeine were augmented twice by TBZ, those of histamine were unaffected; the same happened in rat cortical neurons. Hence, we hypothesize that TBZ facilitates exocytosis by increasing Ca2+ release through the endoplasmic reticulum ryanodine receptor channel (RyR). Confirming this hypothesis are docking results, showing an interaction of TBZ with RyRs. This is consonant with the existence of a healthy Ca2+-induced-Ca2+-release mechanism in BCCs. SIGNIFICANCE STATEMENT: A novel mechanism of action for tetrabenazine (TBZ), a drug used in the therapy of Huntington's disease (HD), is described here. Such mechanism consists of facilitation by combining TBZ with the ryanodine receptor of the endoplasmic reticulum, thereby increasing Ca2+-induced Ca2+ release. This novel mechanism should be taken into account when considering the efficacy and/or safety of TBZ in the treatment of chorea associated with HD and other disorders. Additionally, it could be of interest in the development of novel medicines to treat these pathological conditions.
Collapse
Affiliation(s)
- Ricardo de Pascual
- Instituto Teófilo Hernando, Madrid, Spain (R.d.P., N.Á.-O., C.d.l.R., G.J.-M., A.G.G.); and Departamento de Farmacología y Terapéutica (R.d.P., N.Á.-O., G.J.-M., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa (C.d.l.R., A.G.G.), Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Nuria Álvarez-Ortego
- Instituto Teófilo Hernando, Madrid, Spain (R.d.P., N.Á.-O., C.d.l.R., G.J.-M., A.G.G.); and Departamento de Farmacología y Terapéutica (R.d.P., N.Á.-O., G.J.-M., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa (C.d.l.R., A.G.G.), Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Cristóbal de Los Ríos
- Instituto Teófilo Hernando, Madrid, Spain (R.d.P., N.Á.-O., C.d.l.R., G.J.-M., A.G.G.); and Departamento de Farmacología y Terapéutica (R.d.P., N.Á.-O., G.J.-M., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa (C.d.l.R., A.G.G.), Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Gema Jacob-Mazariego
- Instituto Teófilo Hernando, Madrid, Spain (R.d.P., N.Á.-O., C.d.l.R., G.J.-M., A.G.G.); and Departamento de Farmacología y Terapéutica (R.d.P., N.Á.-O., G.J.-M., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa (C.d.l.R., A.G.G.), Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Instituto Teófilo Hernando, Madrid, Spain (R.d.P., N.Á.-O., C.d.l.R., G.J.-M., A.G.G.); and Departamento de Farmacología y Terapéutica (R.d.P., N.Á.-O., G.J.-M., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa (C.d.l.R., A.G.G.), Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| |
Collapse
|
20
|
Calorio C, Gavello D, Guarina L, Salio C, Sassoè-Pognetto M, Riganti C, Bianchi FT, Hofer NT, Tuluc P, Obermair GJ, Defilippi P, Balzac F, Turco E, Bett GC, Rasmusson RL, Carbone E. Impaired chromaffin cell excitability and exocytosis in autistic Timothy syndrome TS2-neo mouse rescued by L-type calcium channel blockers. J Physiol 2019; 597:1705-1733. [PMID: 30629744 DOI: 10.1113/jp277487] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 12/19/2018] [Indexed: 12/30/2022] Open
Abstract
KEY POINTS Tymothy syndrome (TS) is a multisystem disorder featuring cardiac arrhythmias, autism and adrenal gland dysfunction that originates from a de novo point mutation in the gene encoding the Cav1.2 (CACNA1C) L-type channel. To study the role of Cav1.2 channel signals in autism, the autistic TS2-neo mouse has been generated bearing the G406R point-mutation associated with TS type-2. Using heterozygous TS2-neo mice, we report that the G406R mutation reduces the rate of inactivation and shifts leftward the activation and inactivation of L-type channels, causing marked increase of resting Ca2+ influx ('window' Ca2+ current). The increased 'window current' causes marked reduction of NaV channel density, switches normal tonic firing to abnormal burst firing, reduces mitochondrial metabolism, induces cell swelling and decreases catecholamine release. Overnight incubations with nifedipine rescue NaV channel density, normal firing and the quantity of catecholamine released. We provide evidence that chromaffin cell malfunction derives from altered Cav1.2 channel gating. ABSTRACT L-type voltage-gated calcium (Cav1) channels have a key role in long-term synaptic plasticity, sensory transduction, muscle contraction and hormone release. A point mutation in the gene encoding Cav1.2 (CACNA1C) causes Tymothy syndrome (TS), a multisystem disorder featuring cardiac arrhythmias, autism spectrum disorder (ASD) and adrenal gland dysfunction. In the more severe type-2 form (TS2), the missense mutation G406R is on exon 8 coding for the IS6-helix of the Cav1.2 channel. The mutation causes reduced inactivation and induces autism. How this occurs and how Cav1.2 gating-changes alter cell excitability, neuronal firing and hormone release on a molecular basis is still largely unknown. Here, using the TS2-neo mouse model of TS we show that the G406R mutation altered excitability and reduced secretory activity in adrenal chromaffin cells (CCs). Specifically, the TS2 mutation reduced the rate of voltage-dependent inactivation and shifted leftward the activation and steady-state inactivation of L-type channels. This markedly increased the resting 'window' Ca2+ current that caused an increased percentage of CCs undergoing abnormal action potential (AP) burst firing, cell swelling, reduced mitochondrial metabolism and decreased catecholamine release. The increased 'window' Ca2+ current caused also decreased NaV channel density and increased steady-state inactivation, which contributed to the increased abnormal burst firing. Overnight incubation with the L-type channel blocker nifedipine rescued the normal AP firing of CCs, the density of functioning NaV channels and their steady-state inactivation. We provide evidence that CC malfunction derives from the altered Cav1.2 channel gating and that dihydropyridines are potential therapeutics for ASD.
Collapse
Affiliation(s)
- Chiara Calorio
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Daniela Gavello
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Laura Guarina
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Chiara Salio
- Department of Veterinary Sciences, University of Torino, Torino, Italy
| | - Marco Sassoè-Pognetto
- Department of Neuroscience Rita Levi Montalcini, University of Torino, Torino, Italy
| | - Chiara Riganti
- Department of Oncology, University of Torino, Torino, Italy
| | | | - Nadja T Hofer
- Department of Pharmacology and Toxicology, Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Petronel Tuluc
- Department of Pharmacology and Toxicology, Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Gerald J Obermair
- Department of Physiology & Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Paola Defilippi
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Fiorella Balzac
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Emilia Turco
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Glenna C Bett
- Department of Physiology & Biophysics, State University of New York, Buffalo, NY, USA
| | - Randall L Rasmusson
- Department of Physiology & Biophysics, State University of New York, Buffalo, NY, USA
| | - Emilio Carbone
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| |
Collapse
|
21
|
de Diego AMG, García AG. Altered exocytosis in chromaffin cells from mouse models of neurodegenerative diseases. Acta Physiol (Oxf) 2018; 224:e13090. [PMID: 29742321 DOI: 10.1111/apha.13090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 04/19/2018] [Accepted: 04/25/2018] [Indexed: 12/26/2022]
Abstract
Chromaffin cells from the adrenal gland (CCs) have extensively been used to explore the molecular structure and function of the exocytotic machinery, neurotransmitter release and synaptic transmission. The CC is integrated in the sympathoadrenal axis that helps the body maintain homoeostasis during both routine life and in acute stress conditions. This function is exquisitely controlled by the cerebral cortex and the hypothalamus. We propose the hypothesis that damage undergone by the brain during neurodegenerative diseases is also affecting the neurosecretory function of adrenal medullary CCs. In this context, we review here the following themes: (i) How the discharge of catecholamines is centrally and peripherally regulated at the sympathoadrenal axis; (ii) which are the intricacies of the amperometric techniques used to study the quantal release of single-vesicle exocytotic events; (iii) which are the alterations of the exocytotic fusion pore so far reported, in CCs of mouse models of neurodegenerative diseases; (iv) how some proteins linked to neurodegenerative pathologies affect the kinetics of exocytotic events; (v) finally, we try to integrate available data into a hypothesis to explain how the centrally originated neurodegenerative diseases may alter the kinetics of single-vesicle exocytotic events in peripheral adrenal medullary CCs.
Collapse
Affiliation(s)
- A. M. García de Diego
- Instituto Teófilo Hernando; Universidad Autónoma de Madrid; Madrid Spain
- Instituto de Investigación Sanitaria; Hospital Universitario de la Princesa; Universidad Autónoma de Madrid; Madrid Spain
- DNS Neuroscience; Parque Científico de Madrid; Madrid Spain
| | - A. García García
- Instituto Teófilo Hernando; Universidad Autónoma de Madrid; Madrid Spain
- Instituto de Investigación Sanitaria; Hospital Universitario de la Princesa; Universidad Autónoma de Madrid; Madrid Spain
- DNS Neuroscience; Parque Científico de Madrid; Madrid Spain
- Departamento de Farmacología y Terapéutica; Facultad de Medicina; Universidad Autónoma de Madrid; Madrid Spain
| |
Collapse
|
22
|
Nanclares C, Gameiro-Ros I, Méndez-López I, Martínez-Ramírez C, Padín-Nogueira JF, Colmena I, Baraibar AM, Gandía L, García AG. Dual Antidepressant Duloxetine Blocks Nicotinic Receptor Currents, Calcium Signals and Exocytosis in Chromaffin Cells Stimulated with Acetylcholine. J Pharmacol Exp Ther 2018; 367:28-39. [PMID: 30006476 DOI: 10.1124/jpet.118.250969] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 07/12/2018] [Indexed: 01/09/2023] Open
Abstract
The inhibition of nicotinic acetylcholine receptors (nAChRs) has been proposed as a potential strategy to develop new antidepressant drugs. This is based on the observation that antidepressants that selectively block noradrenaline (NA) or serotonin (5-HT) reuptake also inhibit nAChRs. Dual antidepressants blocking both NA and 5-HT reuptake were proposed to shorten the delay in exerting their clinical effects; whether duloxetine, a prototype of dual antidepressants, also blocks nAChRs is unknown. Here we explored this question in bovine chromaffin cells (BCCs) that express native α3, α5, and α7 nAChRs and in cell lines expressing human α7, α3β4, or α4β2 nAChRs. We have found that duloxetine fully blocked the acetylcholine (ACh)-elicited nicotinic currents in BCCs with an IC50 of 0.86 µM. Such blockade seemed to be noncompetitive, voltage dependent, and partially use dependent. The ACh-elicited membrane depolarization, the elevation of cytosolic calcium ([Ca2+]c), and catecholamine release in BCCs were also blocked by duloxetine. This blockade developed slowly, and the recovery of secretion was also slow and gradual. Duloxetine did not affect Na+ or Ca2+ channel currents neither the high-K+-elicited [Ca2+]c transients and secretion. Of interest was that in cell lines expressing human α7, α3β4, and α4β2 nAChRs, duloxetine blocked nicotinic currents with IC50 values of 0.1, 0.56, and 0.85 µM, respectively. Thus, in blocking α7 receptors, which are abundantly expressed in the brain, duloxetine exhibited approximately 10-fold to 100- fold higher potency with respect to reported IC50 values for various antidepressant drugs. This may contribute to the antidepressant effect of duloxetine.
Collapse
Affiliation(s)
- Carmen Nanclares
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Isabel Gameiro-Ros
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Iago Méndez-López
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Carmen Martínez-Ramírez
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - J Fernando Padín-Nogueira
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Inés Colmena
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Andrés M Baraibar
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Luis Gandía
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| | - Antonio G García
- Instituto Teófilo Hernando and Departamento de Farmacología, Facultad de Medicina (C.N., I.G.-R., I.M.-L., C.M.-R., J.F.P.-N., I.C., A.M.B., L.G., A.G.G.) and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa (A.G.G.), Universidad Autónoma de Madrid, Madrid, Spain; and Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla La Mancha (UCLM), Ciudad Real, Spain (J.F.P.-N.)
| |
Collapse
|
23
|
Baraibar AM, de Pascual R, Camacho M, Domínguez N, David Machado J, Gandía L, Borges R. Distinct patterns of exocytosis elicited by Ca 2+, Sr 2+ and Ba 2+ in bovine chromaffin cells. Pflugers Arch 2018; 470:1459-1471. [PMID: 29926228 DOI: 10.1007/s00424-018-2166-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/24/2018] [Accepted: 06/07/2018] [Indexed: 10/28/2022]
Abstract
Three divalent cations can elicit secretory responses in most neuroendocrine cells, including chromaffin cells. The extent to which secretion is elicited by the cations in intact depolarized cells was Ba2+ > Sr2+ ≥ Ca2+, contrasting with that elicited by these cations in permeabilized cells (Ca2+ > Sr2+ > Ba2+). Current-clamp recordings show that extracellular Sr2+ and Ba2+ cause membrane depolarization and action potentials, which are not blocked by Cd2+ but that can be mimicked by tetra-ethyl-ammonium. When applied intracellularly, only Ba2+ provokes action potentials. Voltage-clamp monitoring of Ca2+-activated K+ channels (KCa) shows that Ba2+ reduces outward currents, which were enhanced by Sr2+. Extracellular Ba2+ increases cytosolic Ca2+ concentrations in Fura-2-loaded intact cells, and it induces long-lasting catecholamine release. Conversely, amperometric recordings of permeabilized cells show that Ca2+ promotes the longest lasting secretion, as Ba2+ only provokes secretion while it is present and Sr2+ induces intermediate-lasting secretion. Intracellular Ba2+ dialysis provokes exocytosis at concentrations 100-fold higher than those of Ca2+, whereas Sr2+ exhibits an intermediate sensitivity. These results are compatible with the following sequence of events: Ba2+ blocks KCa channels from both the outside and inside of the cell, causing membrane depolarization that, in turn, opens voltage-sensitive Ca2+ channels and favors the entry of Ca2+ and Ba2+. Although Ca2+ is less permeable through its own channels, it is more efficient in triggering exocytosis. Strontium possesses both an intermediate permeability and an intermediate ability to induce secretion.
Collapse
Affiliation(s)
- Andrés M Baraibar
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Ricardo de Pascual
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Marcial Camacho
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.,Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Natalia Domínguez
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.,INTEGRARE, Généthon, Inserm, Univ Evry, Université Paris-Saclay, 91002, Evry, France
| | - J David Machado
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain
| | - Luis Gandía
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Ricardo Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain. .,Instituto Universitario de BioOrgánica Antonio González, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.
| |
Collapse
|
24
|
MacDougall DD, Lin Z, Chon NL, Jackman SL, Lin H, Knight JD, Anantharam A. The high-affinity calcium sensor synaptotagmin-7 serves multiple roles in regulated exocytosis. J Gen Physiol 2018; 150:783-807. [PMID: 29794152 PMCID: PMC5987875 DOI: 10.1085/jgp.201711944] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/07/2018] [Indexed: 12/19/2022] Open
Abstract
MacDougall et al. review the structure and function of the calcium sensor synaptotagmin-7 in exocytosis. Synaptotagmin (Syt) proteins comprise a 17-member family, many of which trigger exocytosis in response to calcium. Historically, most studies have focused on the isoform Syt-1, which serves as the primary calcium sensor in synchronous neurotransmitter release. Recently, Syt-7 has become a topic of broad interest because of its extreme calcium sensitivity and diversity of roles in a wide range of cell types. Here, we review the known and emerging roles of Syt-7 in various contexts and stress the importance of its actions. Unique functions of Syt-7 are discussed in light of recent imaging, electrophysiological, and computational studies. Particular emphasis is placed on Syt-7–dependent regulation of synaptic transmission and neuroendocrine cell secretion. Finally, based on biochemical and structural data, we propose a mechanism to link Syt-7’s role in membrane fusion with its role in subsequent fusion pore expansion via strong calcium-dependent phospholipid binding.
Collapse
Affiliation(s)
| | - Zesen Lin
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | - Nara L Chon
- Department of Chemistry, University of Colorado, Denver, CO
| | - Skyler L Jackman
- Vollum Institute, Oregon Health & Science University, Portland, OR
| | - Hai Lin
- Department of Chemistry, University of Colorado, Denver, CO
| | | | - Arun Anantharam
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| |
Collapse
|
25
|
Calorio C, Donno D, Franchino C, Carabelli V, Marcantoni A. Bud extracts from Salix caprea L. inhibit voltage gated calcium channels and catecholamines secretion in mouse chromaffin cells. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2017; 36:168-175. [PMID: 29157811 DOI: 10.1016/j.phymed.2017.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/07/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Salix caprea L. is an ornamental plant with prominent antioxidant activity. In the last decades Salix caprea bud extracts (SCBEs) have been used for the treatment of oxidative stress related disorders. PURPOSE A large part of cellular functions depends on the amount of intracellular Ca2+ concentration which in turn is mainly determined by Ca2+ ions movements across plasma membrane as well as by Ca2+ released from the stores. For better evaluating the mechanism of action of SCBEs, we focused on the effect of SCBEs on voltage gated Ca2+ channels (VGCCs) functioning and related catecholamines secretion in mouse chromaffin cells (MCCs). These latter are neuroendocrine cells that share a wide variety of functions with neurons. They are particularly interesting for studying the relationship between VGCCs activation and catecholamines secretion both in control and under stressful conditions. STUDY DESIGN AND METHODS We focused on the effect of SCBEs on VGCCs being these latter considered one of the main pathway of Ca2+ influx across plasma membrane. Ca2+ currents and capacitance changes were measured in patch clamp experiments performed in voltage clamp configuration. RESULTS We show that SCBEs inhibited VGCCs in a dose dependent manner. On average, the saturating concentration of SCBEs (SCBEsmax) is able to block 36% of the maximum Ca2+ current amplitude (ICa) without selectivity for L (ICa, L) or non-L type (ICa, non-L) Ca2+ channels. Furthermore, ICa inhibition is not followed by alteration of VGCCs gating kinetics, but is responsible for a marked decrease of Ca2+ dependent catecholamines secretion. CONCLUSION We conclude that the ability of SCBEs to inhibit VGCCs function, known to be potentiated during oxidative stress, could contribute to the already known antioxidant properties of Salix caprea L. We finally suggest that the inhibitory effect of SCBEs on catecholamines secretion may contribute to treat stress dependent cellular dysfunctions.
Collapse
Affiliation(s)
- Chiara Calorio
- Department of Drug Science and Technology, University of Torino, Corso Raffaello 30, 10125 Torino, Italy.
| | - Dario Donno
- Department of Agricultural, Forest and Food Sciences (DiSAFA), University of Torino, Largo Braccini 2, 10095 Grugliasco, To, Italy.
| | - Claudio Franchino
- Department of Drug Science and Technology, University of Torino, Corso Raffaello 30, 10125 Torino, Italy.
| | - Valentina Carabelli
- Department of Drug Science and Technology, University of Torino, Corso Raffaello 30, 10125 Torino, Italy.
| | - Andrea Marcantoni
- Department of Drug Science and Technology, University of Torino, Corso Raffaello 30, 10125 Torino, Italy.
| |
Collapse
|
26
|
L-type calcium channels in exocytosis and endocytosis of chromaffin cells. Pflugers Arch 2017; 470:53-60. [DOI: 10.1007/s00424-017-2064-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 08/22/2017] [Accepted: 08/23/2017] [Indexed: 11/25/2022]
|
27
|
Roles of Na +, Ca 2+, and K + channels in the generation of repetitive firing and rhythmic bursting in adrenal chromaffin cells. Pflugers Arch 2017; 470:39-52. [PMID: 28776261 DOI: 10.1007/s00424-017-2048-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 07/23/2017] [Indexed: 12/30/2022]
Abstract
Adrenal chromaffin cells (CCs) are the main source of circulating catecholamines (CAs) that regulate the body response to stress. Release of CAs is controlled neurogenically by the activity of preganglionic sympathetic neurons through trains of action potentials (APs). APs in CCs are generated by robust depolarization following the activation of nicotinic and muscarinic receptors that are highly expressed in CCs. Bovine, rat, mouse, and human CCs also express a composite array of Na+, K+, and Ca2+ channels that regulate the resting potential, shape the APs, and set the frequency of AP trains. AP trains of increasing frequency induce enhanced release of CAs. If the primary role of CCs is simply to relay preganglionic nerve commands to CA secretion, why should they express such a diverse set of ion channels? An answer to this comes from recent observations that, like in neurons, CCs undergo complex firing patterns of APs suggesting the existence of an intrinsic CC excitability (non-neurogenically controlled). Recent work has shown that CCs undergo occasional or persistent burst firing elicited by altered physiological conditions or deletion of pore-regulating auxiliary subunits. In this review, we aim to give a rationale to the role of the many ion channel types regulating CC excitability. We will first describe their functional properties and then analyze how they contribute to pacemaking, AP shape, and burst waveforms. We will also furnish clear indications on missing ion conductances that may be involved in pacemaking and highlight the contribution of the crucial channels involved in burst firing.
Collapse
|
28
|
Rao TC, Santana Rodriguez Z, Bradberry MM, Ranski AH, Dahl PJ, Schmidtke MW, Jenkins PM, Axelrod D, Chapman ER, Giovannucci DR, Anantharam A. Synaptotagmin isoforms confer distinct activation kinetics and dynamics to chromaffin cell granules. J Gen Physiol 2017; 149:763-780. [PMID: 28687607 PMCID: PMC5560776 DOI: 10.1085/jgp.201711757] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/15/2017] [Accepted: 06/12/2017] [Indexed: 01/09/2023] Open
Abstract
Chromaffin cells release transmitters from populations of granules to which synaptotagmin-1 and synaptotagmin-7 are selectively sorted. Rao et al. characterize the functional properties of these granules and show that synaptotagmin-7 confers fast kinetics and high efficacy to the exocytotic event. Adrenomedullary chromaffin cells respond to sympathetic nervous system activation by secreting a cocktail of potent neuropeptides and hormones into the circulation. The distinct phases of the chromaffin cell secretory response have been attributed to the progressive fusion of distinct populations of dense core granules with different activation kinetics. However, it has been difficult to define what distinguishes these populations at the molecular level. Functional segregation of granule pools may depend on selective sorting of synaptotagmin-1 (Syt-1) and synaptotagmin-7 (Syt-7), which our previous work showed are rarely cosorted to the same granule. Here we assess the consequences of selective sorting of Syt isoforms in chromaffin cells, particularly with respect to granule dynamics and activation kinetics. Upon depolarization of cells expressing fluorescent Syt isoforms using elevated K+, we find that Syt-7 granules fuse with faster kinetics than Syt-1 granules, irrespective of stimulation strength. Pharmacological blockade of Ca2+ channels reveals differential dependence of Syt-1 versus Syt-7 granule exocytosis on Ca2+ channel subtypes. Syt-7 granules also show a greater tendency to fuse in clusters than Syt-1 granules, and granules harboring Syt-1 travel a greater distance before fusion than those with Syt-7, suggesting that there is spatial and fusion-site heterogeneity among the two granule populations. However, the greatest functional difference between granule populations is their responsiveness to Ca2+. Upon introduction of Ca2+ into permeabilized cells, Syt-7 granules fuse with fast kinetics and high efficacy, even at low Ca2+ levels (e.g., when cells are weakly stimulated). Conversely, Syt-1 granules require a comparatively larger increase in intracellular Ca2+ for activation. At Ca2+ concentrations above 30 µM, activation kinetics are faster for Syt-1 granules than for Syt-7 granules. Our study provides evidence for functional specialization of chromaffin cell granules via selective expression of Syt isoforms with different Ca2+ sensitivities.
Collapse
Affiliation(s)
- Tejeshwar C Rao
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | | | - Mazdak M Bradberry
- Howard Hughes Medical Institute, Department of Neuroscience, University of Wisconsin, Madison, WI
| | | | - Peter J Dahl
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | | | - Paul M Jenkins
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | - Daniel Axelrod
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | - Edwin R Chapman
- Howard Hughes Medical Institute, Department of Neuroscience, University of Wisconsin, Madison, WI
| | - David R Giovannucci
- Department of Neurosciences, University of Toledo Medical School, Toledo, OH
| | - Arun Anantharam
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
| |
Collapse
|
29
|
López-Gil A, Nanclares C, Méndez-López I, Martínez-Ramírez C, de Los Rios C, Padín-Nogueira JF, Montero M, Gandía L, García AG. The quantal catecholamine release from mouse chromaffin cells challenged with repeated ACh pulses is regulated by the mitochondrial Na + /Ca 2+ exchanger. J Physiol 2017; 595:2129-2146. [PMID: 27982456 DOI: 10.1113/jp273339] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 11/30/2016] [Indexed: 01/09/2023] Open
Abstract
KEY POINTS Upon repeated application of short ACh pulses to C57BL6J mouse chromaffin cells, the amperometrically monitored secretory responses promptly decayed to a steady-state level of around 25% of the initial response. A subsequent K+ pulse, however, overcame such decay. These data suggest that mouse chromaffin cells have a ready release-vesicle pool that is selectively recruited by the physiological neurotransmitter ACh. The ACh-sensitive vesicle pool is refilled and maintained by the rate of Ca2+ delivery from mitochondria to the cytosol, through the mitochondrial Na+ /Ca2+ exchanger (mNCX). ITH12662, a novel blocker of the mNCX, prevented the decay of secretion elicited by ACh pulses and delayed the rate of [Ca2+ ]c clearance. This regulatory pathway may be physiologically relevant in situations of prolonged stressful conflicts where a sustained catecholamine release is regulated by mitochondrial Ca2+ circulation through the mNCX, which couples respiration and ATP synthesis to long-term stimulation of chromaffin cells by endogenously released ACh. ABSTRACT Using caged-Ca2+ photorelease or paired depolarising pulses in voltage-clamped chromaffin cells (CCs), various pools of secretory vesicles with different readiness to undergo exocytosis have been identified. Whether these pools are present in unclamped CCs challenged with ACh, the physiological neurotransmitter at the splanchnic nerve-CC synapse, is unknown. We have explored here whether an ACh-sensitive ready-release vesicle pool (ASP) is present in C57BL6J mouse chromaffin cells (MCCs). Single cells were fast perfused with a Tyrode solution at 37°C, and challenged with 12 sequential ACh pulses (100 μm, 2 s, every 30 s) plus a K+ pulse given at the end (75 mm K+ ). After the first 2-3 ACh pulses the amperometrically monitored secretory responses promptly decayed to a steady-state level of around 25% of the initial response. The last K+ pulse, however, overcame such decay. Repeated ACh pulses to voltage-clamped cells elicited non-desensitising nicotinic currents. Also, the [Ca2+ ]c transients elicited by repeated ACh pulses that were superimposed on a stable baseline elevation did not undergo decay. The novel blocker of the mitochondrial Na+ /Ca2+ exchanger (mNCX) ITH12662 prevented the decay of secretion elicited by ACh pulses and delayed the rate of [Ca2+ ]c clearance. The experiments are compatible with the idea that C57BL6J MCCs have an ASP vesicle pool that is selectively recruited by the physiological neurotransmitter ACh and is regulated by the rate of Ca2+ delivery from mitochondria to the cytosol, through the mNCX.
Collapse
Affiliation(s)
- Angela López-Gil
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Carmen Nanclares
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Iago Méndez-López
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Carmen Martínez-Ramírez
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Cristóbal de Los Rios
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, c/ Diego de León, 62, 28006, Madrid, Spain
| | - J Fernando Padín-Nogueira
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Mayte Montero
- Instituto de Biologia y Genética Molecular, Universidad de Valladolid, c/ Sanz y Forés, 3, 47003, Valladolid, Spain
| | - Luis Gandía
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain
| | - Antonio G García
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, C/ Arzobispo Morcillo, 4, 28029, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, c/ Diego de León, 62, 28006, Madrid, Spain
| |
Collapse
|
30
|
Calvo-Gallardo E, López-Gil Á, Méndez-López I, Martínez-Ramírez C, Padín JF, García AG. Faster kinetics of quantal catecholamine release in mouse chromaffin cells stimulated with acetylcholine, compared with other secretagogues. J Neurochem 2016; 139:722-736. [PMID: 27649809 DOI: 10.1111/jnc.13849] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 08/16/2016] [Accepted: 08/31/2016] [Indexed: 11/27/2022]
Abstract
Adrenal chromaffin cells (CCs) have been used extensively in studies aimed at revealing the intricacies of the Ca2+ -dependent early and late steps of regulated exocytosis. They have also served as invaluable models to study the kinetics of single-vesicle exocytotic events to infer the characteristics of opening and closing of the exocytotic fusion pore. We have here tested the hypothesis that stimulation at room temperature of CCs from mice C57BL/6 with physiological acetylcholine (ACh) and with other secretagogues (dimethylphenylpiperazinium, high K+ , muscarine, histamine, caffeine), alone or in combination, could trigger amperometric spike events with different kinetics. We found that mean secretory spike events in CCs stimulated with ACh had a fast rise rate of 25 pA/ms and a rapid decay time of 6.2 ms, with a small quantal size (0.31 pC). Surprisingly, these parameters considerably differed from those found in CCs stimulated with all other secretagogues that triggered secretory responses with spike events having smaller rise rates, longer decay times and higher quantal sizes. ACh spikes were unaltered by atropine but mitochondrial protonophore carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone markedly slowed down the rate rise and decay time, and augmented the quantal size of mean secretory events. We conclude that the physiological neurotransmitter ACh triggers a fast and efficient exocytotic response that cannot be mimicked by other secretagogues; such response is regulated by the mitochondrial circulation of calcium ions.
Collapse
Affiliation(s)
- Enrique Calvo-Gallardo
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ángela López-Gil
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Iago Méndez-López
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Carmen Martínez-Ramírez
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Juan Fernando Padín
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Servicio de Farmacología Clínica, Hospital Universitario de La Princesa, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Madrid, Spain
| |
Collapse
|
31
|
Toft-Bertelsen TL, Ziomkiewicz I, Houy S, Pinheiro PS, Sørensen JB. Regulation of Ca2+ channels by SNAP-25 via recruitment of syntaxin-1 from plasma membrane clusters. Mol Biol Cell 2016; 27:3329-3341. [PMID: 27605709 PMCID: PMC5170865 DOI: 10.1091/mbc.e16-03-0184] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 09/01/2016] [Indexed: 12/20/2022] Open
Abstract
SNAP-25 regulates Ca2+ channels in an unknown manner. Endogenous and exogenous SNAP-25 inhibit Ca2+ currents indirectly by recruiting syntaxin-1 from clusters on the plasma membrane, thereby making it available for Ca2+ current inhibition. Thus the cell can regulate Ca2+ influx by expanding or contracting syntaxin-1 clusters. SNAP-25 regulates Ca2+ channels, with potentially important consequences for diseases involving an aberrant SNAP-25 expression level. How this regulation is executed mechanistically remains unknown. We investigated this question in mouse adrenal chromaffin cells and found that SNAP-25 inhibits Ca2+ currents, with the B-isoform being more potent than the A-isoform, but not when syntaxin-1 is cleaved by botulinum neurotoxin C. In contrast, syntaxin-1 inhibits Ca2+ currents independently of SNAP-25. Further experiments using immunostaining showed that endogenous or exogenous SNAP-25 expression recruits syntaxin-1 from clusters on the plasma membrane, thereby increasing the immunoavailability of syntaxin-1 and leading indirectly to Ca2+ current inhibition. Expression of Munc18-1, which recruits syntaxin-1 within the exocytotic pathway, does not modulate Ca2+ channels, whereas overexpression of the syntaxin-binding protein Doc2B or ubMunc13-2 increases syntaxin-1 immunoavailability and concomitantly down-regulates Ca2+ currents. Similar findings were obtained upon chemical cholesterol depletion, leading directly to syntaxin-1 cluster dispersal and Ca2+ current inhibition. We conclude that clustering of syntaxin-1 allows the cell to maintain a high syntaxin-1 expression level without compromising Ca2+ influx, and recruitment of syntaxin-1 from clusters by SNAP-25 expression makes it available for regulating Ca2+ channels. This mechanism potentially allows the cell to regulate Ca2+ influx by expanding or contracting syntaxin-1 clusters.
Collapse
Affiliation(s)
- Trine Lisberg Toft-Bertelsen
- Neurosecretion Group, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Iwona Ziomkiewicz
- Neurosecretion Group, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Sébastien Houy
- Neurosecretion Group, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Paulo S Pinheiro
- Neurosecretion Group, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jakob B Sørensen
- Neurosecretion Group, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| |
Collapse
|
32
|
Regulation by L channels of Ca(2+)-evoked secretory responses in ouabain-treated chromaffin cells. Pflugers Arch 2016; 468:1779-92. [PMID: 27558258 DOI: 10.1007/s00424-016-1866-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/21/2016] [Accepted: 08/08/2016] [Indexed: 10/21/2022]
Abstract
It is known that the sustained depolarisation of adrenal medullary bovine chromaffin cells (BCCs) with high K(+) concentrations produces an initial sharp catecholamine release that subsequently fades off in spite depolarisation persists. Here, we have recreated a sustained depolarisation condition of BCCs by treating them with the Na(+)/K(+) ATPase blocker ouabain; in doing so, we searched experimental conditions that permitted the development of a sustained long-term catecholamine release response that could be relevant during prolonged stress. BCCs were perifused with nominal 0Ca(2+) solution, and secretion responses were elicited by intermittent application of short 2Ca(2+) pulses (Krebs-HEPES containing 2 mM Ca(2+)). These pulses elicited a biphasic secretory pattern with an initial 30-min period with secretory responses of increasing amplitude and a second 30-min period with steady-state, non-inactivating responses. The initial phase was not due to gradual depolarisation neither to gradual increases of the cytosolic calcium transients ([Ca(2+)]c) elicited by 2Ca(2+) pulses in BBCs exposed to ouabain; both parameters increased soon after ouabain addition. Νifedipine blocked these responses, and FPL64176 potentiated them, suggesting that they were triggered by Ca(2+) entry through non-inactivating L-type calcium channels. This was corroborated by nifedipine-evoked blockade of the L-type Ca(2+) channel current and the [Ca(2+)]c transients elicited by 2Ca(2+) pulses. Furthermore, the plasmalemmal Na(+)/Ca(2+) exchanger (NCX) blocker SEA0400 caused a mild inhibition followed by a large rebound increase of the steady-state secretory responses. We conclude that these two phases of secretion are mostly contributed by Ca(2+) entry through L calcium channels, with a minor contribution of Ca(2+) entry through the reverse mode of the NCX.
Collapse
|
33
|
Stanika RI, Flucher BE, Obermair GJ. Regulation of Postsynaptic Stability by the L-type Calcium Channel CaV1.3 and its Interaction with PDZ Proteins. Curr Mol Pharmacol 2016; 8:95-101. [PMID: 25966696 PMCID: PMC5384370 DOI: 10.2174/1874467208666150507103716] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 01/29/2015] [Accepted: 04/20/2015] [Indexed: 01/24/2023]
Abstract
Alterations in dendritic spine morphology and postsynaptic structure are a hallmark of neurological disorders. Particularly spine pruning of striatal medium spiny neurons and aberrant rewiring of corticostriatal synapses have been associated with the pathology of Parkinson’s disease and L-DOPA induced dyskinesia, respectively. Owing to its low activation threshold the neuronal L-type calcium channel CaV1.3 is particularly critical in the control of neuronal excitability and thus in the calcium-dependent regulation of neuronal functions. CaV1.3 channels are located in dendritic spines and contain a C-terminal class 1 PDZ domain-binding sequence. Until today the postsynaptic PDZ domain proteins shank, densin-180, and erbin have been shown to interact with CaV1.3 channels and to modulate their current properties. Interestingly experimental evidence suggests an involvement of all three PDZ proteins as well as CaV1.3 itself in regulating dendritic and postsynaptic morphology. Here we briefly review the importance of CaV1.3 and its proposed interactions with PDZ proteins for the stability of dendritic spines. With a special focus on the pathology associated with Parkinson’s disease, we discuss the hypothesis that CaV1.3 L-type calcium channels may be critical modulators of dendritic spine stability.
Collapse
Affiliation(s)
| | | | - Gerald J Obermair
- Division of Physiology, Department of Physiology and Medical Physics, Medical University Innsbruck, Fritz-Pregl-Str. 3, 6020 Innsbruck, Austria.
| |
Collapse
|
34
|
Bedford C, Sears C, Perez-Carrion M, Piccoli G, Condliffe SB. LRRK2 Regulates Voltage-Gated Calcium Channel Function. Front Mol Neurosci 2016; 9:35. [PMID: 27242426 PMCID: PMC4876133 DOI: 10.3389/fnmol.2016.00035] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/06/2016] [Indexed: 11/16/2022] Open
Abstract
Voltage-gated Ca2+ (CaV) channels enable Ca2+ influx in response to membrane depolarization. CaV2.1 channels are localized to the presynaptic membrane of many types of neurons where they are involved in triggering neurotransmitter release. Several signaling proteins have been identified as important CaV2.1 regulators including protein kinases, G-proteins and Ca2+ binding proteins. Recently, we discovered that leucine rich repeat kinase 2 (LRRK2), a protein associated with inherited Parkinson’s disease, interacts with specific synaptic proteins and influences synaptic transmission. Since synaptic proteins functionally interact with CaV2.1 channels and synaptic transmission is triggered by Ca2+ entry via CaV2.1, we investigated whether LRRK2 could impact CaV2.1 channel function. CaV2.1 channel properties were measured using whole cell patch clamp electrophysiology in HEK293 cells transfected with CaV2.1 subunits and various LRRK2 constructs. Our results demonstrate that both wild type (wt) LRRK2 and the G2019S LRRK2 mutant caused a significant increase in whole cell Ca2+ current density compared to cells expressing only the CaV2.1 channel complex. In addition, LRRK2 expression caused a significant hyperpolarizing shift in voltage-dependent activation while having no significant effect on inactivation properties. These functional changes in CaV2.1 activity are likely due to a direct action of LRRK2 as we detected a physical interaction between LRRK2 and the β3 CaV channel subunit via coimmunoprecipitation. Furthermore, effects on CaV2.1 channel function are dependent on LRRK2 kinase activity as these could be reversed via treatment with a LRRK2 inhibitor. Interestingly, LRRK2 also augmented endogenous voltage-gated Ca2+ channel function in PC12 cells suggesting other CaV channels could also be regulated by LRRK2. Overall, our findings support a novel physiological role for LRRK2 in regulating CaV2.1 function that could have implications for how mutations in LRRK2 contribute to Parkinson’s disease pathophysiology.
Collapse
Affiliation(s)
- Cade Bedford
- Department of Physiology, University of Otago Dunedin, New Zealand
| | - Catherine Sears
- Department of Physiology, University of Otago Dunedin, New Zealand
| | | | - Giovanni Piccoli
- Center for Integrative Biology (CIBIO), University of TrentoTrento, Italy; Dulbecco Telethon InstituteTrento, Italy
| | | |
Collapse
|
35
|
Gavello D, Carbone E, Carabelli V. Leptin-mediated ion channel regulation: PI3K pathways, physiological role, and therapeutic potential. Channels (Austin) 2016; 10:282-96. [PMID: 27018500 DOI: 10.1080/19336950.2016.1164373] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Leptin is produced by adipose tissue and identified as a "satiety signal," informing the brain when the body has consumed enough food. Specific areas of the hypothalamus express leptin receptors (LEPRs) and are the primary site of leptin action for body weight regulation. In response to leptin, appetite is suppressed and energy expenditure allowed. Beside this hypothalamic action, leptin targets other brain areas in addition to neuroendocrine cells. LEPRs are expressed also in the hippocampus, neocortex, cerebellum, substantia nigra, pancreatic β-cells, and chromaffin cells of the adrenal gland. It is intriguing how leptin is able to activate different ionic conductances, thus affecting excitability, synaptic plasticity and neurotransmitter release, depending on the target cell. Most of the intracellular pathways activated by leptin and directed to ion channels involve PI3K, which in turn phosphorylates different downstream substrates, although parallel pathways involve AMPK and MAPK. In this review we will describe the effects of leptin on BK, KATP, KV, CaV, TRPC, NMDAR and AMPAR channels and clarify the landscape of pathways involved. Given the ability of leptin to influence neuronal excitability and synaptic plasticity by modulating ion channels activity, we also provide a short overview of the growing potentiality of leptin as therapeutic agent for treating neurological disorders.
Collapse
Affiliation(s)
- Daniela Gavello
- a Department of Drug Science , Lab of Cellular Physiology and Molecular Neuroscience, NIS Center of Excellence, University of Torino , Torino , Italy
| | - Emilio Carbone
- a Department of Drug Science , Lab of Cellular Physiology and Molecular Neuroscience, NIS Center of Excellence, University of Torino , Torino , Italy
| | - Valentina Carabelli
- a Department of Drug Science , Lab of Cellular Physiology and Molecular Neuroscience, NIS Center of Excellence, University of Torino , Torino , Italy
| |
Collapse
|
36
|
De-Miguel FF, Leon-Pinzon C, Noguez P, Mendez B. Serotonin release from the neuronal cell body and its long-lasting effects on the nervous system. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0196. [PMID: 26009775 PMCID: PMC4455765 DOI: 10.1098/rstb.2014.0196] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Serotonin, a modulator of multiple functions in the nervous system, is released predominantly extrasynaptically from neuronal cell bodies, axons and dendrites. This paper describes how serotonin is released from cell bodies of Retzius neurons in the central nervous system (CNS) of the leech, and how it affects neighbouring glia and neurons. The large Retzius neurons contain serotonin packed in electrodense vesicles. Electrical stimulation with 10 impulses at 1 Hz fails to evoke exocytosis from the cell body, but the same number of impulses at 20 Hz promotes exocytosis via a multistep process. Calcium entry into the neuron triggers calcium-induced calcium release, which activates the transport of vesicle clusters to the plasma membrane. Exocytosis occurs there for several minutes. Serotonin that has been released activates autoreceptors that induce an inositol trisphosphate-dependent calcium increase, which produces further exocytosis. This positive feedback loop subsides when the last vesicles in the cluster fuse and calcium returns to basal levels. Serotonin released from the cell body is taken up by glia and released elsewhere in the CNS. Synchronous bursts of neuronal electrical activity appear minutes later and continue for hours. In this way, a brief train of impulses is translated into a long-term modulation in the nervous system.
Collapse
Affiliation(s)
- Francisco F De-Miguel
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Distrito Federal, Mexico
| | - Carolina Leon-Pinzon
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Distrito Federal, Mexico
| | - Paula Noguez
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Distrito Federal, Mexico
| | - Bruno Mendez
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Distrito Federal, Mexico
| |
Collapse
|
37
|
Frolov RV, Weckström M. Harnessing the Flow of Excitation: TRP, Voltage-Gated Na(+), and Voltage-Gated Ca(2+) Channels in Contemporary Medicine. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 103:25-95. [PMID: 26920687 DOI: 10.1016/bs.apcsb.2015.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cellular signaling in both excitable and nonexcitable cells involves several classes of ion channels. Some of them are of minor importance, with very specialized roles in physiology, but here we concentrate on three major channel classes: TRP (transient receptor potential channels), voltage-gated sodium channels (Nav), and voltage-gated calcium channels (Cav). Here, we first propose a conceptual framework binding together all three classes of ion channels, a "flow-of-excitation model" that takes into account the inputs mediated by TRP and other similar channels, the outputs invariably provided by Cav channels, and the regenerative transmission of signals in the neural networks, for which Nav channels are responsible. We use this framework to examine the function, structure, and pharmacology of these channel classes both at cellular and also at whole-body physiological level. Building on that basis we go through the pathologies arising from the direct or indirect malfunction of the channels, utilizing ion channel defects, the channelopathies. The pharmacological interventions affecting these channels are numerous. Part of those are well-established treatments, like treatment of hypertension or some forms of epilepsy, but many other are deeply problematic due to poor drug specificity, ion channel diversity, and widespread expression of the channels in tissues other than those actually targeted.
Collapse
Affiliation(s)
- Roman V Frolov
- Division of Biophysics, Department of Physics, University of Oulu, Oulun Yliopisto, Finland.
| | - Matti Weckström
- Division of Biophysics, Department of Physics, University of Oulu, Oulun Yliopisto, Finland
| |
Collapse
|
38
|
Tight mitochondrial control of calcium and exocytotic signals in chromaffin cells at embryonic life. Pflugers Arch 2015; 467:2589-601. [PMID: 26254593 DOI: 10.1007/s00424-015-1724-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 07/06/2015] [Accepted: 07/20/2015] [Indexed: 01/11/2023]
Abstract
Calcium buffering by mitochondria plays a relevant physiological function in the regulation of Ca(2+) and exocytotic signals in mature chromaffin cells (CCs) from various adult mammals. Whether a similar or different role of mitochondrial Ca(2+) buffering is present in immature CCs at early life has not been explored. Here we present a comparative study in rat embryonic CCs and rat mother CCs, of various physiological parameters that are known to be affected by mitochondrial Ca(2+) buffering during cell activation. We found that the clearance of cytosolic Ca(2+) transients ([Ca(2+)]c) elicited by high K(+) was 7-fold faster in embryo CCs compared to mother CCs. This strongly suggests that at embryonic life, the mitochondria play a more significant role in the clearance of [Ca(2+)]c loads compared to adult life. Consistent with this view are the following results concerning the transient suppression of mitochondrial Ca(2+) buffering by protonophore FCCP, in embryonic CCs compared to mother CCs: (i) faster and greater inactivation of inward calcium currents, (ii) higher K(+)-elicited [Ca(2+)]c transients with 25-fold faster clearance, (iii) higher increase of basal catecholamine release and (iv) higher potentiation of K(+)-evoked secretion. These pronounced differences could be explained by two additional features (embryo versus mother CCs): (a) slower recovery of mitochondrial resting membrane potential after the application of a transient FCCP pulse and (b) greater relative density of the mitochondria in the cytosol. This tighter control by the mitochondria of Ca(2+) and exocytotic signals may be relevant to secure a healthy catecholamine secretory response at early life.
Collapse
|
39
|
Albiñana E, Segura-Chama P, Baraibar AM, Hernández-Cruz A, Hernández-Guijo JM. Different contributions of calcium channel subtypes to electrical excitability of chromaffin cells in rat adrenal slices. J Neurochem 2015; 133:511-21. [DOI: 10.1111/jnc.13055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 12/22/2014] [Accepted: 01/22/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Elisa Albiñana
- Departament of Pharmacology and Therapeutics; University Autónoma de Madrid; Madrid Spain
- Instituto Teófilo Hernando; University Autónoma de Madrid; Madrid Spain
- Facultad de Medicina; University Autónoma de Madrid; Madrid Spain
| | - Pedro Segura-Chama
- Unidad de Investigación de Medicina Experimental; Facultad de Medicina; Universidad Nacional Autónoma de México; Ciudad Universitaria; México City México
| | - Andres M. Baraibar
- Departament of Pharmacology and Therapeutics; University Autónoma de Madrid; Madrid Spain
- Instituto Teófilo Hernando; University Autónoma de Madrid; Madrid Spain
- Facultad de Medicina; University Autónoma de Madrid; Madrid Spain
| | - Arturo Hernández-Cruz
- Departamento de Neurociencia Cognitiva; Instituto de Fisiología Celular; Universidad Nacional Autónoma de México; Ciudad Universitaria; México City México
| | - Jesus M. Hernández-Guijo
- Departament of Pharmacology and Therapeutics; University Autónoma de Madrid; Madrid Spain
- Instituto Teófilo Hernando; University Autónoma de Madrid; Madrid Spain
- Facultad de Medicina; University Autónoma de Madrid; Madrid Spain
| |
Collapse
|
40
|
Fernández-Morales JC, Fernando Padín J, Vestring S, Musial DC, de Diego AMG, García AG. Blockade by NNC 55-0396, mibefradil, and nickel of calcium and exocytotic signals in chromaffin cells: Implications for the regulation of hypoxia-induced secretion at early life. Eur J Pharmacol 2015; 751:1-12. [DOI: 10.1016/j.ejphar.2015.01.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 12/11/2022]
|
41
|
Vandael DHF, Marcantoni A, Carbone E. Cav1.3 Channels as Key Regulators of Neuron-Like Firings and Catecholamine Release in Chromaffin Cells. Curr Mol Pharmacol 2015; 8:149-61. [PMID: 25966692 PMCID: PMC5384372 DOI: 10.2174/1874467208666150507105443] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 01/31/2015] [Accepted: 04/20/2015] [Indexed: 12/19/2022]
Abstract
Neuronal and neuroendocrine L-type calcium channels (Cav1.2, Cav1.3) open readily at relatively low membrane potentials and allow Ca(2+) to enter the cells near resting potentials. In this way, Cav1.2 and Cav1.3 shape the action potential waveform, contribute to gene expression, synaptic plasticity, neuronal differentiation, hormone secretion and pacemaker activity. In the chromaffin cells (CCs) of the adrenal medulla, Cav1.3 is highly expressed and is shown to support most of the pacemaking current that sustains action potential (AP) firings and part of the catecholamine secretion. Cav1.3 forms Ca(2+)-nanodomains with the fast inactivating BK channels and drives the resting SK currents. These latter set the inter-spike interval duration between consecutive spikes during spontaneous firing and the rate of spike adaptation during sustained depolarizations. Cav1.3 plays also a primary role in the switch from "tonic" to "burst" firing that occurs in mouse CCs when either the availability of voltage-gated Na channels (Nav) is reduced or the β2 subunit featuring the fast inactivating BK channels is deleted. Here, we discuss the functional role of these "neuron-like" firing modes in CCs and how Cav1.3 contributes to them. The open issue is to understand how these novel firing patterns are adapted to regulate the quantity of circulating catecholamines during resting condition or in response to acute and chronic stress.
Collapse
Affiliation(s)
| | | | - Emilio Carbone
- Department of Drug Science, Corso Raffaello 30, I - 10125 Torino, Italy.
| |
Collapse
|
42
|
McDavid S, Bauer MB, Brindley RL, Jewell ML, Currie KPM. Butanol isomers exert distinct effects on voltage-gated calcium channel currents and thus catecholamine secretion in adrenal chromaffin cells. PLoS One 2014; 9:e109203. [PMID: 25275439 PMCID: PMC4183593 DOI: 10.1371/journal.pone.0109203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Accepted: 09/08/2014] [Indexed: 12/20/2022] Open
Abstract
Butanol (C4H10OH) has been used both to dissect the molecular targets of alcohols/general anesthetics and to implicate phospholipase D (PLD) signaling in a variety of cellular functions including neurotransmitter and hormone exocytosis. Like other primary alcohols, 1-butanol is a substrate for PLD and thereby disrupts formation of the intracellular signaling lipid phosphatidic acid. Because secondary and tertiary butanols do not undergo this transphosphatidylation, they have been used as controls for 1-butanol to implicate PLD signaling. Recently, selective pharmacological inhibitors of PLD have been developed and, in some cases, fail to block cellular functions previously ascribed to PLD using primary alcohols. For example, exocytosis of insulin and degranulation of mast cells are blocked by primary alcohols, but not by the PLD inhibitor FIPI. In this study we show that 1-butanol reduces catecholamine secretion from adrenal chromaffin cells to a much greater extent than tert-butanol, and that the PLD inhibitor VU0155056 has no effect. Using fluorescent imaging we show the effect of these drugs on depolarization-evoked calcium entry parallel those on secretion. Patch-clamp electrophysiology confirmed the peak amplitude of voltage-gated calcium channel currents (ICa) is inhibited by 1-butanol, with little or no block by secondary or tert-butanol. Detailed comparison shows for the first time that the different butanol isomers exert distinct, and sometimes opposing, effects on the voltage-dependence and gating kinetics of ICa. We discuss these data with regard to PLD signaling in cellular physiology and the molecular targets of general anesthetics.
Collapse
Affiliation(s)
- Sarah McDavid
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Mary Beth Bauer
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Rebecca L. Brindley
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Mark L. Jewell
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Kevin P. M. Currie
- Department of Anesthesiology, Department of Pharmacology, and Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- * E-mail:
| |
Collapse
|
43
|
Todorovic SM, Jevtovic-Todorovic V. Redox regulation of neuronal voltage-gated calcium channels. Antioxid Redox Signal 2014; 21:880-91. [PMID: 24161125 PMCID: PMC4116091 DOI: 10.1089/ars.2013.5610] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
SIGNIFICANCE Voltage-gated calcium channels are ubiquitously expressed in neurons and are key regulators of cellular excitability and synaptic transmitter release. There is accumulating evidence that multiple subtypes of voltage-gated calcium channels may be regulated by oxidation and reduction. However, the redox mechanisms involved in the regulation of channel function are not well understood. RECENT ADVANCES Several studies have established that both T-type and high-voltage-activated subtypes of voltage-gated calcium channel can be redox-regulated. This article reviews different mechanisms that can be involved in redox regulation of calcium channel function and their implication in neuronal function, particularly in pain pathways and thalamic oscillation. CRITICAL ISSUES A current critical issue in the field is to decipher precise mechanisms of calcium channel modulation via redox reactions. In this review we discuss covalent post-translational modification via oxidation of cysteine molecules and chelation of trace metals, and reactions involving nitric oxide-related molecules and free radicals. Improved understanding of the roles of redox-based reactions in regulation of voltage-gated calcium channels may lead to improved understanding of novel redox mechanisms in physiological and pathological processes. FUTURE DIRECTIONS Identification of redox mechanisms and sites on voltage-gated calcium channel may allow development of novel and specific ion channel therapies for unmet medical needs. Thus, it may be possible to regulate the redox state of these channels in treatment of pathological process such as epilepsy and neuropathic pain.
Collapse
Affiliation(s)
- Slobodan M Todorovic
- 1 Department of Anesthesiology, University of Virginia School of Medicine , Charlottesville, Virginia
| | | |
Collapse
|
44
|
Fernández-Morales JC, Padín JF, Arranz-Tagarro JA, Vestring S, García AG, de Diego AMG. Hypoxia-elicited catecholamine release is controlled by L-type as well as N/PQ types of calcium channels in rat embryo chromaffin cells. Am J Physiol Cell Physiol 2014; 307:C455-65. [PMID: 24990647 DOI: 10.1152/ajpcell.00101.2014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
At early life, the adrenal chromaffin cells respond with a catecholamine surge under hypoxic conditions. This response depends on Ca(2+) entry through voltage-activated calcium channels (VACCs). We have investigated here three unresolved questions that concern this response in rat embryo chromaffin cells (ECCs): 1) the relative contribution of L (α1D, Cav1.3), N (α1B, Cav2.2), and PQ (α1A, Cav2.1) to the whole cell Ca(2+) current (ICa); 2) the relative contribution of L and N/PQ channels to the cytosolic Ca(2+) elevations triggered by hypoxia (Δ[Ca(2+)]c); and 3) the role of L and non-L high-VACCs in the regulation of the catecholamine surge occurring during prolonged (1 min) hypoxia exposure of ECCs. Nimodipine halved peak ICa and blocked 60% the total Ca(2+) entry during a 50-ms depolarizing pulse to 0 mV (QCa). Combined ω-agatoxin IVA plus ω-conotoxin GVIA (Aga/GVIA) blocked 30% of both ICa peak and QCa. This relative proportion of L- and non-L VACCs was corroborated by Western blot that indicated 55, 23, and 25% relative expression of L, N, and PQ VACCs. Exposure of ECCs to hypoxia elicited a mild but sustained Δ[Ca(2+)]c; the area of Δ[Ca(2+)]c was blocked 50% by nifedipine and 10% by Aga/GVIA. Exposure of ECCs to 1-min hypoxia elicited an initial transient burst of amperometric secretory spikes followed by scattered spikes along the time of cell exposure to hypoxia. This bulk response was blocked 85% by nimodipine and 35% by Aga/GVIA. Histograms on secretory spike frequency vs. time indicated a faster initial inactivation when Ca(2+) entry took place through N/PQ channels; more sustained secretion but at a lower rate was associated to Ca(2+) entry through L channels. The results suggest that the HIS response may initially be controlled by L and P/Q channels, but later on, N/PQ channels inactivate and the delayed HIS response is maintained at lower rate by slow-inactivating L channels.
Collapse
Affiliation(s)
- José-Carlos Fernández-Morales
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Juan-Fernando Padín
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Juan-Alberto Arranz-Tagarro
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Stefan Vestring
- Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Antonio G García
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Servicio de Farmacología Clínica, Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Madrid, Spain; and
| | - Antonio Miguel G de Diego
- Instituto Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain;
| |
Collapse
|
45
|
Wen X, Xu S, Liu H, Liang H, Yang C, Wang H. Construction and identification of the pshRNA-CACNA1G-SH-SY5Ycells targeted to silence Cav3.1 mRNA expression. Biomed Rep 2014; 1:669-673. [PMID: 24649007 DOI: 10.3892/br.2013.117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/23/2013] [Indexed: 11/05/2022] Open
Abstract
T-type calcium channels are a class of low voltage-dependent calcium channels that may be activated following minor depolarizations of the cell membrane. Cav3.1 is the dominant subtype of the T-type calcium channel in SH-SY5Y cells. T-type channels play a key role in the regulation of the intracellular calcium concentration, which is involved in the neurotoxic effect of local anesthetics. However, there is a lack of specific inhibitors of T-type calcium channels. The existing T-type calcium channel inhibitors exhibit poor specificity and may block the high voltage-dependent calcium channels, such as the L- and N-type channels. Furthermore, there is no selectivity to the subtype of the T-type calcium channel. Therefore, the development of a specific T-type calcium channel inhibitor may contribute to the elucidation of the functions and characteristics of T-type calcium channels. The aim of this study was to silence the Cav3.1 mRNA expression in SH-SY5Y cells via the RNA interference (RNAi) method in order to construct pshRNA-CACNA1G-SH-SY5Y cells and assess Cav3.1 mRNA and protein expression by western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) to identify the constructed cell line. The results demonstrated that Cav3.1 mRNA and protein expression were significantly reduced following transfection with the SH-SY5Y cells by the supernatant liquors. The results also demonstrated that the pshRNA-CACNA1G-SH-SY5Y cells were successfully constructed. These findings may contribute to the elucidation of the functions of Cav3.1 in SH-SY5Y cells.
Collapse
Affiliation(s)
- Xianjie Wen
- Department of Anesthesiology, Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong 510282, P.R. China ; Department of Anesthesiology, The First People's Hospital of Foshan and Foshan Hospital of Sun Yat-Sen University, Foshan, Guangdong 528000, P.R. China
| | - Shiyuan Xu
- Department of Anesthesiology, Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Hongzhen Liu
- Department of Anesthesiology, The First People's Hospital of Foshan and Foshan Hospital of Sun Yat-Sen University, Foshan, Guangdong 528000, P.R. China
| | - Hua Liang
- Department of Anesthesiology, The First People's Hospital of Foshan and Foshan Hospital of Sun Yat-Sen University, Foshan, Guangdong 528000, P.R. China
| | - Chenxiang Yang
- Department of Anesthesiology, The First People's Hospital of Foshan and Foshan Hospital of Sun Yat-Sen University, Foshan, Guangdong 528000, P.R. China
| | - Hanbing Wang
- Department of Anesthesiology, The First People's Hospital of Foshan and Foshan Hospital of Sun Yat-Sen University, Foshan, Guangdong 528000, P.R. China
| |
Collapse
|
46
|
T-type channel-mediated neurotransmitter release. Pflugers Arch 2014; 466:677-87. [PMID: 24595475 DOI: 10.1007/s00424-014-1489-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 02/18/2014] [Indexed: 10/25/2022]
Abstract
Besides controlling a wide variety of cell functions, T-type channels have been shown to regulate neurotransmitter release in peripheral and central synapses and neuroendocrine cells. Growing evidence over the last 10 years suggests a key role of Cav3.2 and Cav3.1 channels in controlling basal neurosecretion near resting conditions and sustained release during mild stimulations. In some cases, the contribution of low-voltage-activated (LVA) channels is not directly evident but requires either the activation of coupled presynaptic receptors, block of ion channels, or chelation of metal ions. Concerning the coupling to the secretory machinery, T-type channels appear loosely coupled to neurotransmitter and hormone release. In neurons, Cav3.2 and Cav3.1 channels mainly control the asynchronous appearance of "minis" [miniature inhibitory postsynaptic currents (mIPSCs) and miniature excitatory postsynaptic currents (mEPSCs)]. The same loose coupling is evident from membrane capacity and amperometric recordings in chromaffin cells and melanotropes where the low-threshold-driven exocytosis possesses the same linear Ca(2+) dependence of the other voltage-gated Ca(2+) channels (Cav1 and Cav2) that is strongly attenuated by slow calcium buffers. The intriguing issue is that, despite not expressing a consensus "synprint" site, Cav3.2 channels do interact with syntaxin 1A and SNAP-25 and, thus, may form nanodomains with secretory vesicles that can be regulated at low voltages. In this review, we discuss all the past and recent issues related to T-type channel-secretion coupling in neurons and neuroendocrine cells.
Collapse
|
47
|
Michaela P, Mária K, Silvia H, L'ubica L. Bisphenol A differently inhibits CaV3.1, Ca V3.2 and Ca V3.3 calcium channels. Naunyn Schmiedebergs Arch Pharmacol 2013; 387:153-63. [PMID: 24170242 DOI: 10.1007/s00210-013-0932-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 10/16/2013] [Indexed: 01/26/2023]
Abstract
Bisphenol A (BPA) is a widespread environmental contaminant detected in urine of 93 % of investigated US population. Recent epidemiological studies found correlation between BPA exposure and diseases including cardiovascular and neuronal disorders. BPA targets include hormone receptors and voltage-dependent ion channels. T-type calcium channels are important regulatory elements in both cardiovascular and neuronal system. Therefore, we investigated effects of BPA on T-type calcium channels. Calcium current flowing through recombinant T-type calcium channels expressed in HEK 293 cells was measured using whole-cell patch clamp. BPA inhibited the current through individual T-type calcium channel subtypes in a concentration-dependent manner with two distinguishable components in these concentration-dependencies. Nanomolar concentrations of BPA inhibited calcium current through T-type calcium channels in the order of efficiency CaV3.2 ≥ CaV3.1 > CaV3.3 without affecting voltage dependence and kinetics of channel gating. Micromolar concentrations of BPA accelerated kinetics of current decay, shifted voltage dependence of steady-state inactivation towards more negative values and inhibited current amplitudes. We suggest that BPA acts as a modifier of channel gating and directly plugs conductive channel pore at high concentration. Concentration range in which inhibition was observed corresponds to concentrations detected in human fluids and therefore may be relevant for evaluation of health effects of BPA.
Collapse
Affiliation(s)
- Pavlovičová Michaela
- Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Vlárska 5, 833 34, Bratislava, Slovak Republic
| | | | | | | |
Collapse
|
48
|
Rapid responses to reverse T₃ hormone in immature rat Sertoli cells: calcium uptake and exocytosis mediated by integrin. PLoS One 2013; 8:e77176. [PMID: 24130850 PMCID: PMC3795021 DOI: 10.1371/journal.pone.0077176] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 08/31/2013] [Indexed: 11/19/2022] Open
Abstract
There is increasing experimental evidence of the nongenomic action of thyroid hormones mediated by receptors located in the plasma membrane or inside cells. The aim of this work was to characterize the reverse T₃ (rT₃) action on calcium uptake and its involvement in immature rat Sertoli cell secretion. The results presented herein show that very low concentrations of rT₃ are able to increase calcium uptake after 1 min of exposure. The implication of T-type voltage-dependent calcium channels and chloride channels in the effect of rT₃ was evidenced using flunarizine and 9-anthracene, respectively. Also, the rT₃-induced calcium uptake was blocked in the presence of the RGD peptide (an inhibitor of integrin-ligand interactions). Therefore, our findings suggest that calcium uptake stimulated by rT₃ may be mediated by integrin αvβ₃. In addition, it was demonstrated that calcium uptake stimulated by rT₃ is PKC and ERK-dependent. Furthermore, the outcomes indicate that rT₃ also stimulates cellular secretion since the cells manifested a loss of fluorescence after 4 min incubation, indicating an exocytic quinacrine release that seems to be mediated by the integrin receptor. These findings indicate that rT₃ modulates the calcium entry and cellular secretion, which might play a role in the regulation of a plethora of intracellular processes involved in male reproductive physiology.
Collapse
|
49
|
Picollo F, Gosso S, Vittone E, Pasquarelli A, Carbone E, Olivero P, Carabelli V. A new diamond biosensor with integrated graphitic microchannels for detecting quantal exocytic events from chromaffin cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:4696-700. [PMID: 23847004 DOI: 10.1002/adma.201300710] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/07/2013] [Indexed: 05/15/2023]
Abstract
An MeV ion-microbeam lithographic technique can be successfully employed for the fabrication of an all-carbon miniaturized cellular biosensor based on graphitic microchannels embedded in a single-crystal diamond matrix. The device is functionally characterized for the in vitro recording of quantal exocytic events from single chromaffin cells, with high sensitivity and signal-to-noise ratio, opening promising perspectives for the realization of monolithic all-carbon cellular biosensors.
Collapse
Affiliation(s)
- Federico Picollo
- Department of Physics, NIS Centre of Excellence, CNISM Research Unit - University of Torino, INFN Sez. Torino, via P. Giuria 1, Torino, 10125, Italy.
| | | | | | | | | | | | | |
Collapse
|
50
|
Hiersemenzel K, Brown ER, Duncan RR. Imaging large cohorts of single ion channels and their activity. Front Endocrinol (Lausanne) 2013; 4:114. [PMID: 24027557 PMCID: PMC3762133 DOI: 10.3389/fendo.2013.00114] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/16/2013] [Indexed: 01/16/2023] Open
Abstract
As calcium is the most important signaling molecule in neurons and secretory cells, amongst many other cell types, it follows that an understanding of calcium channels and their regulation of exocytosis is of vital importance. Calcium imaging using calcium dyes such as Fluo3, or FRET-based dyes that have been used widely has provided invaluable information, which combined with modeling has estimated the subtypes of channels responsible for triggering the exocytotic machinery as well as inferences about the relative distances away from vesicle fusion sites these molecules adopt. Importantly, new super-resolution microscopy techniques, combined with novel Ca(2+) indicators and imaginative imaging approaches can now define directly the nano-scale locations of very large cohorts of single channel molecules in relation to single vesicles. With combinations of these techniques the activity of individual channels can be visualized and quantified using novel Ca(2+) indicators. Fluorescently labeled specific channel toxins can also be used to localize endogenous assembled channel tetramers. Fluorescence lifetime imaging microscopy and other single-photon-resolution spectroscopic approaches offer the possibility to quantify protein-protein interactions between populations of channels and the SNARE protein machinery for the first time. Together with simultaneous electrophysiology, this battery of quantitative imaging techniques has the potential to provide unprecedented detail describing the locations, dynamic behaviors, interactions, and conductance activities of many thousands of channel molecules and vesicles in living cells.
Collapse
Affiliation(s)
- Katia Hiersemenzel
- Edinburgh Super-Resolution Imaging Consortium (ESRIC), Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Euan R. Brown
- Edinburgh Super-Resolution Imaging Consortium (ESRIC), Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Rory R. Duncan
- Edinburgh Super-Resolution Imaging Consortium (ESRIC), Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
- *Correspondence: Rory R. Duncan, Edinburgh Super-Resolution Imaging Consortium (ESRIC), Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK e-mail:
| |
Collapse
|