1
|
Burda PC, Ramaprasad A, Bielfeld S, Pietsch E, Woitalla A, Söhnchen C, Singh MN, Strauss J, Sait A, Collinson LM, Schwudke D, Blackman MJ, Gilberger TW. Global analysis of putative phospholipases in Plasmodium falciparum reveals an essential role of the phosphoinositide-specific phospholipase C in parasite maturation. mBio 2023; 14:e0141323. [PMID: 37489900 PMCID: PMC10470789 DOI: 10.1128/mbio.01413-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 07/26/2023] Open
Abstract
For its replication within red blood cells, the malaria parasite depends on a highly active and regulated lipid metabolism. Enzymes involved in lipid metabolic processes such as phospholipases are, therefore, potential drug targets. Here, using reverse genetics approaches, we show that only 1 out of the 19 putative phospholipases expressed in asexual blood stages of Plasmodium falciparum is essential for proliferation in vitro, pointing toward a high level of redundancy among members of this enzyme family. Using conditional mislocalization and gene disruption techniques, we show that this essential phosphoinositide-specific phospholipase C (PI-PLC, PF3D7_1013500) has a previously unrecognized essential role during intracellular parasite maturation, long before its previously perceived role in parasite egress and invasion. Subsequent lipidomic analysis suggests that PI-PLC mediates cleavage of phosphatidylinositol bisphosphate (PIP2) in schizont-stage parasites, underlining its critical role in regulating phosphoinositide levels in the parasite. IMPORTANCE The clinical symptoms of malaria arise due to repeated rounds of replication of Plasmodium parasites within red blood cells (RBCs). Central to this is an intense period of membrane biogenesis. Generation of membranes not only requires de novo synthesis and acquisition but also the degradation of phospholipids, a function that is performed by phospholipases. In this study, we investigate the essentiality of the 19 putative phospholipase enzymes that the human malaria parasite Plasmodium falciparum expresses during its replication within RBCs. We not only show that a high level of functional redundancy exists among these enzymes but, at the same time, also identify an essential role for the phosphoinositide-specific phospholipase C in parasite development and cleavage of the phospholipid phosphatidylinositol bisphosphate.
Collapse
Affiliation(s)
- Paul-Christian Burda
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Abhinay Ramaprasad
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Sabrina Bielfeld
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Emma Pietsch
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Anna Woitalla
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Christoph Söhnchen
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Mehar Nihal Singh
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London, United Kingdom
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Jan Strauss
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| | - Aaron Sait
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Lucy M. Collinson
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
- German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany
- German Center for Lung Research (DZL), Airway Research Center North (ARCN), Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Michael J. Blackman
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London, United Kingdom
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Tim-Wolf Gilberger
- Centre for Structural Systems Biology, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- University of Hamburg, Hamburg, Germany
| |
Collapse
|
2
|
Feldthouse MG, Vyleta NP, Smith SM. PLC regulates spontaneous glutamate release triggered by extracellular calcium and readily releasable pool size in neocortical neurons. Front Cell Neurosci 2023; 17:1193485. [PMID: 37260580 PMCID: PMC10228687 DOI: 10.3389/fncel.2023.1193485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 04/26/2023] [Indexed: 06/02/2023] Open
Abstract
Introduction Dynamic physiological changes in brain extracellular calcium ([Ca2+]o) occur when high levels of neuronal activity lead to substantial Ca2+ entry via ion channels reducing local [Ca2+]o. Perturbations of the extracellular microenvironment that increase [Ca2+]o are commonly used to study how [Ca2+] regulates neuronal activity. At excitatory synapses, the Ca2+-sensing receptor (CaSR) and other G-protein coupled receptors link [Ca2+]o and spontaneous glutamate release. Phospholipase C (PLC) is activated by G-proteins and is hypothesized to mediate this process. Methods Patch-clamping cultured neocortical neurons, we tested how spontaneous glutamate release was affected by [Ca2+]o and inhibition of PLC activity. We used hypertonic sucrose (HS) to evaluate the readily releasable pool (RRP) and test if it was affected by inhibition of PLC activity. Results Spontaneous glutamate release substantially increased with [Ca2+]o, and inhibition of PLC activity, with U73122, abolished this effect. PLC-β1 is an abundant isoform in the neocortex, however, [Ca2+]o-dependent spontaneous release was unchanged in PLC-β1 null mutants (PLC-β1-/-). U73122 completely suppressed this response in PLC-β1-/- neurons, indicating that this residual [Ca2+]o-sensitivity may be mediated by other PLC isoforms. The RRP size was substantially reduced after incubation in U73122, but not U73343. Phorbol esters increased RRP size after PLC inhibition. Discussion Together these data point to a strong role for PLC in mediating changes in spontaneous release elicited by [Ca2+]o and other extracellular cues, possibly by modifying the size of the RRP.
Collapse
Affiliation(s)
- Maya G. Feldthouse
- Section of Pulmonary and Critical Care Medicine and Research and Development, VA Portland Health Care System, Portland, OR, United States
| | - Nicholas P. Vyleta
- Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, United States
| | - Stephen M. Smith
- Section of Pulmonary and Critical Care Medicine and Research and Development, VA Portland Health Care System, Portland, OR, United States
- Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, United States
| |
Collapse
|
3
|
Expression of the C-Terminal Domain of Phospholipase Cβ3 Inhibits Signaling via Gαq-Coupled Receptors and Transient Receptor Potential Channels. Int J Mol Sci 2022; 23:ijms23179590. [PMID: 36076982 PMCID: PMC9455670 DOI: 10.3390/ijms23179590] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/20/2022] [Accepted: 08/21/2022] [Indexed: 11/22/2022] Open
Abstract
Transient receptor potential (TRP) channels are cation channels that play a regulatory role in pain and thermosensation, insulin secretion, and neurotransmission. It has been proposed that activation of TRP channels requires phosphatidylinositol 4,5-bisphosphate, the major substrate for phospholipase C (PLC). We investigated whether inhibition of PLCβ has an impact on TRP channel signaling. A genetic approach was used to avoid off-target effects observed when using a pharmacological PLCβ inhibitor. In this study, we show that expression of PLCβ1ct and PLCβ3ct, truncated forms of PLCβ1 or PLCβ3 that contain the C-terminal membrane binding domains, almost completely blocked the signal transduction of a Gαq-coupled designer receptor, including the phosphorylation of ERK1/2. In contrast, expression of the helix-turn-helix motif (Hα1—Hα2) of the proximal C-terminal domain of PLCβ3 did not affect Gαq-coupled receptor signaling. PLCβ3ct expression impaired signaling of the TRP channels TRPM3 and TRPM8, stimulated with either prognenolone sulfate or icilin. Thus, the C-terminal domain of PLCβ3 interacts with plasma membrane targets, most likely phosphatidylinositol 4,5-bisphosphate, and in this way blocks the biological activation of TRPM3 and TRPM8, which require interaction with this phospholipid. PLCβ thus regulates TRPM3 and TRPM8 channels by masking phosphatidylinositol 4,5-bisphosphate with its C-terminal domain.
Collapse
|
4
|
Tappia PS, Ramjiawan B, Dhalla NS. Role of Phospholipase C in Catecholamine-induced Increase in Myocardial Protein Synthesis. Can J Physiol Pharmacol 2022; 100:945-955. [PMID: 35767883 DOI: 10.1139/cjpp-2022-0189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of the α1-adrenoceptor-(α1-AR) by norepinephrine results in the G-protein (Gqα) mediated increase in the phosphoinositide-specific phospholipase C (PLC) activity. The byproducts of PLC hydrolytic activity, namely, 1,2-diacylglycerol and inositol-1,4,5-trisphosphate, are important downstream signal transducers for increased protein synthesis in the cardiomyocyte and the subsequent hypertrophic response. In this article, evidence is outlined to demonstrate the role of cardiomyocyte PLC isozymes in the catecholamine-induced increase in protein synthesis by using a blocker of α1-AR and an inhibitor of PLC. The discussion will be focused on the α1-AR-Gqα-PLC-mediated hypertrophic signaling pathway from the viewpoint that it may compliment the other β1-AR-Gs protein-adenylyl cyclase signal transduction mechanisms in the early stages of cardiac hypertrophy development, but may become more relevant at the late stage of cardiac hypertrophy. From the information provided here, it is suggested that some specific PLC isozymes may potentially serve as important targets for the attenuation of cardiac hypertrophy in the vulnerable patient population at-risk for heart failure.
Collapse
Affiliation(s)
- Paramjit S Tappia
- Asper Clinical Research Institute, St. Boniface Hospital, Office of Clinical Research, Winnipeg, Manitoba, Canada;
| | - Bram Ramjiawan
- University of Manitoba, Faculty of Medicine, Winnipeg, Manitoba, Canada;
| | - Naranjan S Dhalla
- St Boniface Hospital Research, 120927, Institute of Cardiovascular Sciences, Albrechtsen Research Centre, Winnipeg, Manitoba, Canada;
| |
Collapse
|
5
|
Kovács ZM, Dienes C, Hézső T, Almássy J, Magyar J, Bányász T, Nánási PP, Horváth B, Szentandrássy N. Pharmacological Modulation and (Patho)Physiological Roles of TRPM4 Channel—Part 1: Modulation of TRPM4. Pharmaceuticals (Basel) 2022; 15:ph15010081. [PMID: 35056138 PMCID: PMC8781449 DOI: 10.3390/ph15010081] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/06/2022] [Indexed: 02/06/2023] Open
Abstract
Transient receptor potential melastatin 4 is a unique member of the TRPM protein family and, similarly to TRPM5, is Ca2+-sensitive and permeable to monovalent but not divalent cations. It is widely expressed in many organs and is involved in several functions by regulating the membrane potential and Ca2+ homeostasis in both excitable and non-excitable cells. This part of the review discusses the pharmacological modulation of TRPM4 by listing, comparing, and describing both endogenous and exogenous activators and inhibitors of the ion channel. Moreover, other strategies used to study TRPM4 functions are listed and described. These strategies include siRNA-mediated silencing of TRPM4, dominant-negative TRPM4 variants, and anti-TRPM4 antibodies. TRPM4 is receiving more and more attention and is likely to be the topic of research in the future.
Collapse
Affiliation(s)
- Zsigmond Máté Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Hézső
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence:
| |
Collapse
|
6
|
Mandal S, Bandyopadhyay S, Tyagi K, Roy A. Recent advances in understanding the molecular role of phosphoinositide-specific phospholipase C gamma 1 as an emerging onco-driver and novel therapeutic target in human carcinogenesis. Biochim Biophys Acta Rev Cancer 2021; 1876:188619. [PMID: 34454048 DOI: 10.1016/j.bbcan.2021.188619] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/04/2021] [Accepted: 08/21/2021] [Indexed: 02/07/2023]
Abstract
Phosphoinositide metabolism is crucial intracellular signaling system that regulates a plethora of biological functions including mitogenesis, cell proliferation and division. Phospholipase C gamma 1 (PLCγ1) which belongs to phosphoinositide-specific phospholipase C (PLC) family, is activated by many extracellular stimuli including hormones, neurotransmitters, growth factors and modulates several cellular and physiological functions necessary for tumorigenesis such as cell survival, migration, invasion and angiogenesis by generating inositol 1,4,5-triphosphate (IP3) and diacylglycerol (DAG) via hydrolysis of phosphatidylinositol 4,5-biphosphate (PIP2). Cancer remains as a leading cause of global mortality and aberrant expression and regulation of PLCγ1 is linked to a plethora of deadly human cancers including carcinomas of the breast, lung, pancreas, stomach, prostate and ovary. Although PLCγ1 cross-talks with many onco-drivers and signaling circuits including PI3K, AKT, HIF1-α and RAF/MEK/ERK cascade, its precise role in carcinogenesis is not completely understood. This review comprehensively discussed the status quo of this ubiquitously expressed phospholipase as a tumor driver and highlighted its significance as a novel therapeutic target in cancer. Furthermore, we have highlighted the significance of somatic driver mutations in PLCG1 gene and molecular roles of PLCγ1 in several major human cancers, a knowledgebase that can be utilized to develop novel, isoform-specific small molecule inhibitors of PLCγ1.
Collapse
Affiliation(s)
- Supratim Mandal
- Department of Microbiology, University of Kalyani, Kalyani, Nadia, West Bengal 741235, India.
| | - Shrabasti Bandyopadhyay
- Department of Microbiology, University of Kalyani, Kalyani, Nadia, West Bengal 741235, India
| | - Komal Tyagi
- Amity Institute of Molecular Medicine & Stem Cell Research, Amity University, Sector 125, Noida, Uttar Pradesh 201303, India
| | - Adhiraj Roy
- Amity Institute of Molecular Medicine & Stem Cell Research, Amity University, Sector 125, Noida, Uttar Pradesh 201303, India.
| |
Collapse
|
7
|
Thein W, Po WW, Kim DM, Sohn UD. The Altered Signaling on EFS-Induced Colon Contractility in Diabetic Rats. Biomol Ther (Seoul) 2020; 28:328-336. [PMID: 32126734 PMCID: PMC7327146 DOI: 10.4062/biomolther.2019.181] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/24/2019] [Accepted: 01/07/2020] [Indexed: 01/18/2023] Open
Abstract
Diabetes mellitus affects the colonic motility developing gastrointestinal symptoms, such as constipation. The aim of the study was to examine the role of intracellular signaling pathways contributing to colonic dysmotility in diabetes mellitus. To generate diabetes mellitus, the rats were injected by a single high dose of streptozotocin (65 mg/kg) intraperitoneally. The proximal colons from both normal and diabetic rats were contracted by applying an electrical field stimulation with pulse voltage of 40 V in amplitude and pulse duration of 1 ms at frequencies of 1, 2, 4, and 6 Hz. The muscle strips from both normal rats and rats with diabetes mellitus were pretreated with different antagonists and inhibitors. Rats with diabetes mellitus had lower motility than the control group. There were significant differences in the percentage of inhibition of contraction between normal rats and rats with diabetes mellitus after the incubation of tetrodotoxin (neuronal blocker), atropine (muscarinic receptor antagonist), prazosin (α1 adrenergic receptor antagonist), DPCPX (adenosine A1 receptor antagonist), verapamil (L-type Ca2+ channel blocker), U73122 (PLC inhibitor), ML-9 (MLCK inhibitor), udenafil (PDE5 inhibitor), and methylene blue (guanylate cyclase inhibitor). The protein expression of p-MLC and PDE5 were decreased in the diabetic group compared to the normal group. These results showed that the reduced colonic contractility resulted from the impaired neuronal conduction and decreased muscarinic receptor sensitivity, which resulted in decreased phosphorylation of MLC via MLCK, and cGMP activity through PDE5.
Collapse
Affiliation(s)
- Wynn Thein
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Wah Wah Po
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Dong Min Kim
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Uy Dong Sohn
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| |
Collapse
|
8
|
Simonowski A, Wilhelm T, Habib P, Zorn CN, Huber M. Differential use of BTK and PLC in FcεRI- and KIT-mediated mast cell activation: A marginal role of BTK upon KIT activation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1867:118622. [PMID: 31837347 DOI: 10.1016/j.bbamcr.2019.118622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 11/16/2019] [Accepted: 12/08/2019] [Indexed: 02/04/2023]
Abstract
In mast cells (MCs), the TEC family kinase (TFK) BTK constitutes a central regulator of antigen (Ag)-triggered, FcεRI-mediated PLCγ phosphorylation, Ca2+ mobilization, degranulation, and pro-inflammatory cytokine production. Less is known about the function of BTK in the context of stem cell factor (SCF)-induced KIT signaling. In bone marrow-derived MCs (BMMCs), Ag stimulation caused intense phosphorylation of BTK at Y551 in its active center and at Y223 in its SH3-domain, whereas in response to SCF only Y223 was significantly phosphorylated. Further data using the TFK inhibitor Ibrutinib indicated that BTK Y223 is phosphorylated by a non-BTK TFK upon SCF stimulation. In line, SCF-induced PLCγ1 phosphorylation was stronger attenuated by Ibrutinib than by BTK deficiency. Subsequent pharmacological analysis of PLCγ function revealed a total block of SCF-induced Ca2+ mobilization by PLC inhibition, whereas only the sustained phase of Ca2+ flux was curtailed in Ag-stimulated BMMCs. Despite this severe stimulus-dependent difference in inducing Ca2+ mobilization, PLCγ inhibition suppressed Ag- and SCF-induced degranulation and pro-inflammatory cytokine production to comparable extents, suggesting involvement of additional TFK(s) or PLCγ-dependent signaling components. In addition to PLCγ, the MAPKs p38 and JNK were activated by Ag in a BTK-dependent manner; this was not observed upon SCF stimulation. Hence, FcεRI and KIT employ different mechanisms for activating PLCγ, p38, and JNK, which might strengthen their cooperation regarding pro-inflammatory MC effector functions. Importantly, our data clearly demonstrate that analyzing BTK Y223 phosphorylation is not sufficient to prove BTK activation.
Collapse
Affiliation(s)
- Anne Simonowski
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Thomas Wilhelm
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Pardes Habib
- Department of Neurology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Carolin N Zorn
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Michael Huber
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany.
| |
Collapse
|
9
|
The phospholipase C inhibitor U73122 is a potent agonist of the polymodal transient receptor potential ankyrin type 1 (TRPA1) receptor channel. Naunyn Schmiedebergs Arch Pharmacol 2019; 393:177-189. [DOI: 10.1007/s00210-019-01722-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/26/2019] [Indexed: 01/07/2023]
|
10
|
Ibeh CL, Yiu AJ, Kanaras YL, Paal E, Birnbaumer L, Jose PA, Bandyopadhyay BC. Evidence for a regulated Ca 2+ entry in proximal tubular cells and its implication in calcium stone formation. J Cell Sci 2019; 132:jcs.225268. [PMID: 30910829 DOI: 10.1242/jcs.225268] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 03/14/2019] [Indexed: 12/14/2022] Open
Abstract
Calcium phosphate (CaP) crystals, which begin to form in the early segments of the loop of Henle (LOH), are known to act as precursors for calcium stone formation. The proximal tubule (PT), which is just upstream of the LOH and is a major site for Ca2+ reabsorption, could be a regulator of such CaP crystal formation. However, PT Ca2+ reabsorption is mostly described as being paracellular. Here, we show the existence of a regulated transcellular Ca2+ entry pathway in luminal membrane PT cells induced by Ca2+-sensing receptor (CSR, also known as CASR)-mediated activation of transient receptor potential canonical 3 (TRPC3) channels. In support of this idea, we found that both CSR and TRPC3 are physically and functionally coupled at the luminal membrane of PT cells. More importantly, TRPC3-deficient mice presented with a deficiency in PT Ca2+ entry/transport, elevated urinary [Ca2+], microcalcifications in LOH and urine microcrystals formations. Taken together, these data suggest that a signaling complex comprising CSR and TRPC3 exists in the PT and can mediate transcellular Ca2+ transport, which could be critical in maintaining the PT luminal [Ca2+] to mitigate formation of the CaP crystals in LOH and subsequent formation of calcium stones.
Collapse
Affiliation(s)
- Cliff-Lawrence Ibeh
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, 50 Irving Street, NW, Washington DC, DC 20422, USA
| | - Allen J Yiu
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, 50 Irving Street, NW, Washington DC, DC 20422, USA.,Department of Medicine, Division of Renal Diseases & Hypertension, The George Washington University, Washington DC, DC 20037, USA
| | - Yianni L Kanaras
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, 50 Irving Street, NW, Washington DC, DC 20422, USA
| | - Edina Paal
- Pathology and Laboratory Service, Veterans Affairs Medical Center, 50 Irving Street, NW, Washington DC, DC 20422, USA
| | - Lutz Birnbaumer
- Division of Intramural Research, NIEHS, Research Triangle Park, Durham, NC 27709, USA.,Institute for Biomedical Research (BIOMED), Catholic University of Argentina, C1107AFF Buenos Aires, Argentina
| | - Pedro A Jose
- Department of Medicine, Division of Renal Diseases & Hypertension, The George Washington University, Washington DC, DC 20037, USA.,Department of Pharmacology and Physiology, The George Washington University, Washington DC, DC 20037, USA
| | - Bidhan C Bandyopadhyay
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, 50 Irving Street, NW, Washington DC, DC 20422, USA .,Department of Medicine, Division of Renal Diseases & Hypertension, The George Washington University, Washington DC, DC 20037, USA.,Department of Pharmacology and Physiology, The George Washington University, Washington DC, DC 20037, USA
| |
Collapse
|
11
|
Torres-Cruz FM, César Vivar-Cortés I, Moran I, Mendoza E, Gómez-Pineda V, García-Sierra F, Hernández-Echeagaray E. NT-4/5 antagonizes the BDNF modulation of corticostriatal transmission: Role of the TrkB.T1 receptor. CNS Neurosci Ther 2019; 25:621-631. [PMID: 30666798 PMCID: PMC6488875 DOI: 10.1111/cns.13091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 11/14/2018] [Accepted: 11/19/2018] [Indexed: 12/14/2022] Open
Abstract
Neurotrophins are related to survival, growth, differentiation and neurotrophic maintenance as well as modulation of synaptic transmission in different regions of the nervous system. BDNF effects have been studied in the striatum due to the trophic role of BDNF in medium spiny neurons; however, less is known about the effects of NT‐4/5, which is also present in the striatum and activates the TrkB receptor along with BDNF. If both neurotrophins are present in the striatum, the following question arises: What role do they play in striatal physiology? Thus, the aim of this study was to determine the physiological effect of the sequential application and coexistence of BDNF and NT‐4/5 on the modulation of corticostriatal synapses. Our data demonstrated that neurotrophins exhibit differential effects depending on exposure order. BDNF did not modify NT‐4/5 effect; however, NT‐4/5 inhibited the effects of BDNF. Experiments carried out in COS‐7 cells to understand the mechanisms of this antagonism, indicated that NT‐4/5 exerts its inhibitory effect on BDNF by upregulating the TrkB.T1 and downregulating the TrkB‐FL isoforms of the TrkB receptor.
Collapse
Affiliation(s)
- Francisco M Torres-Cruz
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Israel César Vivar-Cortés
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Isaac Moran
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Ernesto Mendoza
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Victor Gómez-Pineda
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | | | - Elizabeth Hernández-Echeagaray
- Laboratorio de Neurofisiología del Desarrollo y la Neurodegeneración, UBIMED, FES-Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| |
Collapse
|
12
|
Lunz V, Romanin C, Frischauf I. STIM1 activation of Orai1. Cell Calcium 2019; 77:29-38. [PMID: 30530091 DOI: 10.1016/j.ceca.2018.11.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/20/2018] [Accepted: 11/28/2018] [Indexed: 11/23/2022]
Abstract
A primary calcium (Ca2+) entry pathway into non-excitable cells is through the store-operated Ca2+ release activated Ca2+ (CRAC) channel. Ca2+ entry into cells is responsible for the initiation of diverse signalling cascades that affect essential cellular processes like gene regulation, cell growth and death, secretion and gene transcription. Upon depletion of intracellular Ca2+ stores within the endoplasmic reticulum (ER), the CRAC channel opens to refill depleted stores. The two key limiting molecular players of the CRAC channel are the stromal interaction molecule (STIM1) embedded in the ER-membrane and Orai1, residing in the plasma membrane (PM), respectively. Together, they form a highly Ca2+ selective ion channel complex. STIM1 senses the Ca2+ content of the ER and confers Ca2+ store-depletion into the opening of Orai1 channels in the PM for triggering Ca2+-dependent gene transcription, T-cell activation or mast cell degranulation. The interplay of Orai and STIM proteins in the CRAC channel signalling cascade has been the main focus of research for more than twelve years. This chapter focuses on current knowledge and main experimental advances in the understanding of Orai1 activation by STIM1, thereby portraying key mechanistic steps in the CRAC channel signalling cascade.
Collapse
Affiliation(s)
- Victoria Lunz
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria.
| | - Irene Frischauf
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria.
| |
Collapse
|
13
|
Jung HJ, Im SS, Song DK, Bae JH. Effects of chlorogenic acid on intracellular calcium regulation in lysophosphatidylcholine-treated endothelial cells. BMB Rep 2018; 50:323-328. [PMID: 28088946 PMCID: PMC5498143 DOI: 10.5483/bmbrep.2017.50.6.182] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Indexed: 12/31/2022] Open
Abstract
Lysophosphatidylcholine (LPC) is a major phospholipid component of oxidized low-density lipoprotein (ox-LDL) and is implicated in its atherogenic activity. This study investigated the effects of LPC on cell viability, intracellular calcium homeostasis, and the protective mechanisms of chlorogenic acid (CGA) in human umbilical vein endothelial cells (HUVECs). LPC increased intracellular calcium ([Ca2+]i) by releasing Ca2+ from intracellular stores and via Ca2+ influx through store-operated channels (SOCs). LPC also increased the generation of reactive oxygen species (ROS) and decreased cell viability. The mRNA expression of Transient receptor potential canonical (TRPC) channel 1 was increased significantly by LPC treatment and suppressed by CGA. CGA inhibited LPC-induced Ca2+ influx and ROS generation, and restored cell viability. These results suggested that CGA inhibits SOC-mediated Ca2+ influx and ROS generation by attenuating TRPC1 expression in LPC-treated HUVECs. Therefore, CGA might protect endothelial cells against LPC injury, thereby inhibiting atherosclerosis.
Collapse
Affiliation(s)
- Hye-Jin Jung
- Department of Physiology, Keimyung University School of Medicine, Daegu 42601, Korea
| | - Seung-Soon Im
- Department of Physiology, Keimyung University School of Medicine, Daegu 42601, Korea
| | - Dae-Kyu Song
- Department of Physiology, Keimyung University School of Medicine, Daegu 42601, Korea
| | - Jae-Hoon Bae
- Department of Physiology, Keimyung University School of Medicine, Daegu 42601, Korea
| |
Collapse
|
14
|
Muller MS, Taylor CW. ATP evokes Ca 2+ signals in cultured foetal human cortical astrocytes entirely through G protein-coupled P2Y receptors. J Neurochem 2017; 142:876-885. [PMID: 28677119 PMCID: PMC5601250 DOI: 10.1111/jnc.14119] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/15/2017] [Accepted: 06/29/2017] [Indexed: 01/07/2023]
Abstract
Extracellular ATP plays important roles in coordinating the activities of astrocytes and neurons, and aberrant signalling is associated with neurodegenerative diseases. In rodents, ATP stimulates opening of Ca2+‐permeable channels formed by P2X receptor subunits in the plasma membrane. It is widely assumed, but not verified, that P2X receptors also evoke Ca2+ signals in human astrocytes. Here, we directly assess this hypothesis. We showed that cultured foetal cortical human astrocytes express mRNA for several P2X receptor subunits (P2X4, P2X5, P2X6) and G protein‐coupled P2Y receptors (P2Y1, P2Y2, P2Y6, P2Y11). In these astrocytes, ATP stimulated Ca2+ release from intracellular stores through IP3 receptors and store‐operated Ca2+ entry. These responses were entirely mediated by P2Y1 and P2Y2 receptors. Agonists of P2X receptors did not evoke Ca2+ signals, and nor did ATP when Ca2+ release from intracellular stores and store‐operated Ca2+ entry were inhibited. We conclude that ATP‐evoked Ca2+ signals in cultured human foetal astrocytes are entirely mediated by P2Y1 and P2Y2 receptors, with no contribution from P2X receptors. ![]()
Collapse
Affiliation(s)
- Margit S Muller
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| |
Collapse
|
15
|
Qu H, Guan Y, Wang Y, Zhang S. PLC-Mediated Signaling Pathway in Pollen Tubes Regulates the Gametophytic Self-incompatibility of Pyrus Species. FRONTIERS IN PLANT SCIENCE 2017; 8:1164. [PMID: 28729872 PMCID: PMC5498517 DOI: 10.3389/fpls.2017.01164] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 06/16/2017] [Indexed: 05/27/2023]
Abstract
Among the Rosaceae species, the gametophytic self-incompatibility (GSI) is controlled by a single multi-allelic S locus, which is composed of the pistil-S and pollen-S genes. The pistil-S gene encodes a polymorphic ribonuclease (S-RNase), which is essential for identifying self-pollen. However, the S-RNase system has not been fully characterized. In this study, the self-S-RNase inhibited the Ca2+-permeable channel activity at pollen tube apices and the selectively decreased phospholipase C (PLC) activity in the plasma membrane of Pyrus pyrifolia pollen tubes. Self-S-RNase decreased the Ca2+ influx through a PLC-mediated signaling pathway. Phosphatidylinositol-specific PLC has a 26-amino acid insertion in pollen tubes of the 'Jinzhuili' cultivar, which is a spontaneous self-compatible mutant of the 'Yali' cultivar. 'Yali' plants exhibit a typical S-RNase-based GSI. Upon self-pollination, PLC gene expression is significantly higher in 'Jinzhuili' pollen tubes than that in 'Yali' pollen tubes. Moreover, the PLC in pollen tubes can only interact with one of the two types of S-RNase from the style. In the Pyrus x bretschneideri Rehd, the PLC directly interacted with the S7-RNase in the pollen tube, but not with the S34-RNase. Collectively, our results reveal that the effects of S-RNase on PLC activity are required for S-specific pollen rejection, and that PLC-IP3 participates in the self-incompatibility reaction of Pyrus species.
Collapse
Affiliation(s)
- Haiyong Qu
- College of Horticulture, Qingdao Agricultural UniversityQingdao, China
| | - Yaqin Guan
- College of Horticulture, Qingdao Agricultural UniversityQingdao, China
| | - Yongzhang Wang
- College of Horticulture, Qingdao Agricultural UniversityQingdao, China
| | - Shaolin Zhang
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| |
Collapse
|
16
|
Yiu AJ, Ibeh CL, Roy SK, Bandyopadhyay BC. Melamine induces Ca 2+-sensing receptor activation and elicits apoptosis in proximal tubular cells. Am J Physiol Cell Physiol 2017; 313:C27-C41. [PMID: 28381520 DOI: 10.1152/ajpcell.00225.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 03/29/2017] [Accepted: 03/30/2017] [Indexed: 01/06/2023]
Abstract
Melamine causes renal tubular cell injury through inflammation, fibrosis, and apoptosis. Although melamine affects the rise in intracellular Ca2+ concentration ([Ca2+]i), reactive oxygen species (ROS) production, and proapoptotic pathway activation, the mechanism of upstream Ca2+ signaling is unknown. Because melamine has some structural similarities with l-amino acids, which endogenously activate Ca2+-sensing receptors (CSR), we examined the effect of melamine on CSR-induced Ca2+ signaling and apoptotic cell death. We show here that melamine activates CSR, causing a sustained Ca2+ entry in the renal epithelial cell line, LLC-PK1. Moreover, such CSR stimulation resulted in a rise in [Ca2+]i, leading to enhanced ROS production. Furthermore, melamine-induced elevated [Ca2+]i and ROS production caused a dose-dependent increase in apoptotic (by DAPI staining, DNA laddering, and annexin V assay) and necrotic (propidium iodide staining) cell death. Upon examining the downstream mechanism, we found that transforming growth factor β1 (TGF-β1), which increases extracellular matrix genes and proapoptotic signaling, was also upregulated at lower doses of melamine, which could be due to an early event inducing apoptosis. Additionally, cells exposed to melamine displayed a rise in pERK activation and lactate dehydrogenase release resulting in cytotoxicity. These results offer a novel insight into the molecular mechanisms by which melamine exerts its effect on CSR, causing a sustained elevation of [Ca2+]i, leading to ROS generation, fibronectin production, proapoptotic pathway activation, and renal cell damage. Together, these results thus suggest that melamine-induced apoptosis and/or necrosis may subsequently result in acute kidney injury and promote kidney stone formation.
Collapse
Affiliation(s)
- Allen J Yiu
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, District of Columbia.,Department of Pharmacology and Physiology, School of Medicine, George Washington University, Washington, District of Columbia; and
| | - Cliff-Lawrence Ibeh
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, District of Columbia
| | - Sanjit K Roy
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, District of Columbia
| | - Bidhan C Bandyopadhyay
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, District of Columbia; .,Department of Pharmacology and Physiology, School of Medicine, George Washington University, Washington, District of Columbia; and.,Department of Pharmacology and Physiology, Georgetown University, Washington, District of Columbia
| |
Collapse
|
17
|
Han JM, Tanimura A, Kirk V, Sneyd J. A mathematical model of calcium dynamics in HSY cells. PLoS Comput Biol 2017; 13:e1005275. [PMID: 28199326 PMCID: PMC5310762 DOI: 10.1371/journal.pcbi.1005275] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 11/30/2016] [Indexed: 12/03/2022] Open
Abstract
Saliva is an essential part of activities such as speaking, masticating and swallowing. Enzymes in salivary fluid protect teeth and gums from infectious diseases, and also initiate the digestion process. Intracellular calcium (Ca2+) plays a critical role in saliva secretion and regulation. Experimental measurements of Ca2+ and inositol trisphosphate (IP3) concentrations in HSY cells, a human salivary duct cell line, show that when the cells are stimulated with adenosine triphosphate (ATP) or carbachol (CCh), they exhibit coupled oscillations with Ca2+ spike peaks preceding IP3 spike peaks. Based on these data, we construct a mathematical model of coupled Ca2+ and IP3 oscillations in HSY cells and perform model simulations of three different experimental settings to forecast Ca2+ responses. The model predicts that when Ca2+ influx from the extracellular space is removed, oscillations gradually slow down until they stop. The model simulation of applying a pulse of IP3 predicts that photolysis of caged IP3 causes a transient increase in the frequency of the Ca2+ oscillations. Lastly, when Ca2+-dependent activation of PLC is inhibited, we see an increase in the oscillation frequency and a decrease in the amplitude. These model predictions are confirmed by experimental data. We conclude that, although concentrations of Ca2+ and IP3 oscillate, Ca2+ oscillations in HSY cells are the result of modulation of the IP3 receptor by intracellular Ca2+, and that the period is modulated by the accompanying IP3 oscillations.
Collapse
Affiliation(s)
- Jung Min Han
- Department of Mathematics, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Akihiko Tanimura
- Department of Pharmacology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
| | - Vivien Kirk
- Department of Mathematics, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - James Sneyd
- Department of Mathematics, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| |
Collapse
|
18
|
Khin PP, Zaw TS, Sohn UD. Signal Transduction Underlying the Inhibitory Mechanism of Fluoxetine on Electrical Field Stimulation Response in Rat Ileal Smooth Muscle. Pharmacology 2017; 99:216-225. [DOI: 10.1159/000449528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 09/01/2016] [Indexed: 11/19/2022]
|
19
|
Charles E, Hammadi M, Kischel P, Delcroix V, Demaurex N, Castelbou C, Vacher AM, Devin A, Ducret T, Nunes P, Vacher P. The antidepressant fluoxetine induces necrosis by energy depletion and mitochondrial calcium overload. Oncotarget 2017; 8:3181-3196. [PMID: 27911858 PMCID: PMC5356874 DOI: 10.18632/oncotarget.13689] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/21/2016] [Indexed: 11/25/2022] Open
Abstract
Selective Serotonin Reuptake Inhibitor antidepressants, such as fluoxetine (Prozac), have been shown to induce cell death in cancer cells, paving the way for their potential use as cancer therapy. These compounds are able to increase cytosolic calcium concentration ([Ca2+]cyt), but the involved mechanisms and their physiological consequences are still not well understood. Here, we show that fluoxetine induces an increase in [Ca2+]cyt by emptying the endoplasmic reticulum (ER) through the translocon, an ER Ca2+ leakage structure. Our data also show that fluoxetine inhibits oxygen consumption and lowers mitochondrial ATP. This latter is essential for Ca2+ reuptake into the ER, and we postulated therefore that the fluoxetine-induced decrease in mitochondrial ATP production results in the emptying of the ER, leading to capacitative calcium entry. Furthermore, Ca2+ quickly accumulated in the mitochondria, leading to mitochondrial Ca2+ overload and cell death. We found that fluoxetine could induce an early necrosis in human peripheral blood lymphocytes and Jurkat cells, and could also induce late apoptosis, especially in the tumor cell line. These results shed light on fluoxetine-induced cell death and its potential use in cancer treatment.
Collapse
Affiliation(s)
- Emilie Charles
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Mehdi Hammadi
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Philippe Kischel
- Laboratory of Cellular and Molecular Physiology EA4667, Université de Picardie Jules Verne, SFR CAP-SANTE (FED 4231), Amiens, France
| | - Vanessa Delcroix
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Nicolas Demaurex
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Cyril Castelbou
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Anne-Marie Vacher
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Anne Devin
- Institut de Biochimie et Génétique Cellulaires, UMR 5095, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Thomas Ducret
- INSERM U1045, Centre de Recherche Cardio-Thoracique, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Paula Nunes
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Pierre Vacher
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| |
Collapse
|
20
|
Leitner MG, Michel N, Behrendt M, Dierich M, Dembla S, Wilke BU, Konrad M, Lindner M, Oberwinkler J, Oliver D. Direct modulation of TRPM4 and TRPM3 channels by the phospholipase C inhibitor U73122. Br J Pharmacol 2016; 173:2555-69. [PMID: 27328745 DOI: 10.1111/bph.13538] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 06/10/2016] [Accepted: 06/15/2016] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Signalling through phospholipase C (PLC) controls many cellular processes. Much information on the relevance of this important pathway has been derived from pharmacological inhibition of the enzymatic activity of PLC. We found that the most frequently employed PLC inhibitor, U73122, activates endogenous ionic currents in widely used cell lines. Given the extensive use of U73122 in research, we set out to identify these U73122-sensitive ion channels. EXPERIMENTAL APPROACH We performed detailed biophysical analysis of the U73122-induced currents in frequently used cell lines. KEY RESULTS At concentrations required to inhibit PLC, U73122 modulated the activity of transient receptor potential melastatin (TRPM) channels through covalent modification. U73122 was shown to be a potent agonist of ubiquitously expressed TRPM4 channels and activated endogenous TRPM4 channels in CHO cells independently of PLC and of the downstream second messengers PI(4,5)P2 and Ca(2+) . U73122 also potentiated Ca(2) (+) -dependent TRPM4 currents in human Jurkat T-cells, endogenous TRPM4 in HEK293T cells and recombinant human TRPM4. In contrast to TRPM4, TRPM3 channels were inhibited whereas the closely related TRPM5 channels were insensitive to U73122, showing that U73122 exhibits high specificity within the TRPM channel family. CONCLUSIONS AND IMPLICATIONS Given the widespread expression of TRPM4 and TRPM3 channels, these actions of U73122 must be considered when interpreting its effects on cell function. U73122 may also be useful for identifying and characterizing TRPM channels in native tissue, thus facilitating the analysis of their physiology.
Collapse
Affiliation(s)
- Michael G Leitner
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Niklas Michel
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Marc Behrendt
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Marlen Dierich
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Sandeep Dembla
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Bettina U Wilke
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Maik Konrad
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Moritz Lindner
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany.,Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Johannes Oberwinkler
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| | - Dominik Oliver
- Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps-University Marburg, Marburg, Germany
| |
Collapse
|
21
|
Min CH, Min YS, Lee SJ, Sohn UD. The comparative effects of aminoglycoside antibiotics and muscle relaxants on electrical field stimulation response in rat bladder smooth muscle. Arch Pharm Res 2016; 39:863-70. [PMID: 27260628 DOI: 10.1007/s12272-016-0765-1] [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: 03/23/2016] [Accepted: 05/24/2016] [Indexed: 10/21/2022]
Abstract
It has been reported that several aminoglycoside antibiotics have a potential of prolonging the action of non-depolarizing muscle relaxants by drug interactions acting pre-synaptically to inhibit acetylcholine release, but antibiotics itself also have a strong effect on relaxing the smooth muscle. In this study, four antibiotics of aminoglycosides such as gentamicin, streptomycin, kanamycin and neomycin were compared with skeletal muscle relaxants baclofen, tubocurarine, pancuronium and succinylcholine, and a smooth muscle relaxant, papaverine. The muscle strips isolated from the rat bladder were stimulated with pulse trains of 40 V in amplitude and 10 s in duration, with pulse duration of 1 ms at the frequency of 1-8 Hz, at 1, 2, 4, 6, 8 Hz respectively. To test the effect of four antibiotics on bladder smooth muscle relaxation, each of them was treated cumulatively from 1 μM to 0.1 mM with an interval of 5 min. Among the four antibiotics, gentamicin and neomycin inhibited the EFS response. The skeletal muscle relaxants (baclofen, tubocurarine, pancuronium and succinylcholine) and inhibitory neurotransmitters (GABA and glycine) did not show any significant effect. However, papaverine, had a significant effect in the relaxation of the smooth muscle. It was suggested that the aminoglycoside antibiotics have inhibitory effect on the bladder smooth muscle.
Collapse
Affiliation(s)
- Chang Ho Min
- College of Pharmacy, Chung-Ang University, Seoul, 156-756, Republic of Korea
| | - Young Sil Min
- Department of Medical Plant Science, Jung Won University, Chungbuk, Republic of Korea
| | - Sang Joon Lee
- College of Pharmacy, Chung-Ang University, Seoul, 156-756, Republic of Korea.
| | - Uy Dong Sohn
- College of Pharmacy, Chung-Ang University, Seoul, 156-756, Republic of Korea.
| |
Collapse
|
22
|
Lo Vasco VR, Leopizzi M, Di Maio V, Della Rocca C. U-73122 reduces the cell growth in cultured MG-63 ostesarcoma cell line involving Phosphoinositide-specific Phospholipases C. SPRINGERPLUS 2016; 5:156. [PMID: 27026853 PMCID: PMC4766154 DOI: 10.1186/s40064-016-1768-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 02/12/2016] [Indexed: 11/24/2022]
Abstract
The definition of the number and nature of the signal transduction pathways involved in the pathogenesis and the identification of the molecules promoting metastasis spread might improve the knowledge of the natural history of osteosarcoma, also allowing refine the prognosis and opening the way to novel therapeutic strategies. Phosphatydil inositol (4,5) bisphosphate (PIP2), belonging to the Phosphoinositide (PI) signal transduction pathway, was related to the regulation of ezrin, an ezrin-radixin-moesin protein involved in metastatic osteosarcoma spread. The levels of PIP2 are regulated by means of the PI-specific Phospholipase C (PLC) enzymes. Recent literature data suggested that in osteosarcoma the panel of expression of PLC isoforms varies in a complex and unclear manner and is related to ezrin, probably networking with Ras GTPases, such as RhoA and Rac1. We analyzed the expression and the subcellular localization of PLC enzymes in cultured human osteosarcoma MG-63 cells, commonly used as an experimental model for human osteoblasts, using U-73122 PLC inhibitor, U-73343 inactive analogue, and by silencing ezrin. The treatment with U-73122 significantly reduces the number of MG-63 viable cells and contemporarily modifies the expression and the subcellular localization of selected PLC isoforms. U-73122 reduces the cell growth in cultured MG-63 ostesarcoma cell line involving PI-specific Phospholipases C.
Collapse
Affiliation(s)
- Vincenza Rita Lo Vasco
- />Sensory Organs Department, Policlinico Umberto I, Faculty of Medicine and Dentistry, Sapienza University of Rome, viale dell’Università, 33, 00157 Rome, Italy
| | - Martina Leopizzi
- />Medico-Surgical Sciences and Biotechnology Department, Polo Pontino- Sapienza University of Rome, 04100 Latina, Italy
| | - Valeria Di Maio
- />Medico-Surgical Sciences and Biotechnology Department, Polo Pontino- Sapienza University of Rome, 04100 Latina, Italy
| | - Carlo Della Rocca
- />Medico-Surgical Sciences and Biotechnology Department, Polo Pontino- Sapienza University of Rome, 04100 Latina, Italy
| |
Collapse
|
23
|
Expressing an inhibitor of PLCβ1b sustains contractile function following pressure overload. J Mol Cell Cardiol 2016; 93:12-7. [PMID: 26906633 DOI: 10.1016/j.yjmcc.2016.02.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 01/29/2016] [Accepted: 02/17/2016] [Indexed: 01/19/2023]
Abstract
The activity of phospholipase Cβ1b (PLCβ1b) is selectively elevated in failing myocardium and cardiac expression of PLCβ1b causes contractile dysfunction. PLCβ1b can be selectively inhibited by expressing a peptide inhibitor that prevents sarcolemmal localization. The inhibitory peptide, PLCβ1b-CT was expressed in heart from a mini-gene using adeno-associated virus (rAAV6-PLCβ1b-CT). rAAV6-PLCβ1b-CT, or blank virus, was delivered IV (4×10(9)vg/g body weight) and trans-aortic-constriction (TAC) or sham-operation was performed 8weeks later. Expression of PLCβ1b-CT prevented the loss of contractile function, eliminated lung congestion and improved survival following TAC with either a 'moderate' or 'severe' pressure gradient. Hypertrophy was attenuated but not eliminated. Expression of the PLCβ1b-CT peptide 2-3weeks after TAC reduced contractile dysfunction and lung congestion, without limiting hypertrophy. PLCβ1b inhibition ameliorates pathological responses following acute pressure overload. The targeting of PLCβ1b to the sarcolemma provides the basis for the development of a new class of inotropic agent.
Collapse
|
24
|
Brochet M, Billker O. Calcium signalling in malaria parasites. Mol Microbiol 2016; 100:397-408. [PMID: 26748879 DOI: 10.1111/mmi.13324] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2016] [Indexed: 12/24/2022]
Abstract
Ca(2+) is a ubiquitous intracellular messenger in malaria parasites with important functions in asexual blood stages responsible for malaria symptoms, the preceding liver-stage infection and transmission through the mosquito. Intracellular messengers amplify signals by binding to effector molecules that trigger physiological changes. The characterisation of some Ca(2+) effector proteins has begun to provide insights into the vast range of biological processes controlled by Ca(2+) signalling in malaria parasites, including host cell egress and invasion, protein secretion, motility and cell cycle regulation. Despite the importance of Ca(2+) signalling during the life cycle of malaria parasites, little is known about Ca(2+) homeostasis. Recent findings highlighted that upstream of stage-specific Ca(2+) effectors is a conserved interplay between second messengers to control critical intracellular Ca(2+) signals throughout the life cycle. The identification of the molecular mechanisms integrating stage-transcending mechanisms of Ca(2+) homeostasis in a network of stage-specific regulator and effector pathways now represents a major challenge for a meaningful understanding of Ca(2+) signalling in malaria parasites.
Collapse
Affiliation(s)
- Mathieu Brochet
- Faculty of Medicine, Department of Microbiology and Molecular Medicine, University of Geneva, 1 Rue Michel-Servet, CH-1211 Geneva 4, Switzerland.,UMR5235 CNRS-Université Montpellier 2, 34095, Montpellier, France
| | - Oliver Billker
- Wellcome Trust Sanger Institute, Malaria Programme, CB10 1SA, Hinxton, UK
| |
Collapse
|
25
|
Meireles M, Moura E, Vieira-Coelho MA, Santos-Buelga C, Gonzalez-Manzano S, Dueñas M, Mateus N, Faria A, Calhau C. Flavonoids as dopaminergic neuromodulators. Mol Nutr Food Res 2016; 60:495-501. [PMID: 26582321 DOI: 10.1002/mnfr.201500557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/28/2015] [Accepted: 10/31/2015] [Indexed: 12/25/2022]
Abstract
SCOPE The present study aimed to characterize and evaluate flavonoids effects on organic cation uptake in neuronal cells. METHODS AND RESULTS Uptake experiments were conducted using radiolabeled methyl-4-phenylpyridinuim ([(3) H]-MPP(+) ), in human neuronal dopaminergic cells, SH-SY5Y. Catechin did not alter [(3) H]-MPP(+) uptake, however its metabolite 4'-methyl-catechin decreased it by almost 50%. Epicatechin and its methylated metabolites also decreased [(3) H]-MPP(+) uptake. Interestingly, the quercetin flavonol and its metabolite conjugated with glucuronic acid, as well as the flavanones naringenin and hesperitin, increased [(3) H]-MPP(+) uptake. CONCLUSION These results showed that different classes of flavonoids, as well as its metabolites, differently influence neuronal organic cation uptake. Several xeno- and endobiotics, including neurotransmitters, are organic cations. Specific food recommendations may be beneficial in pathological conditions where levels of neurotransmitters, as dopamine, are either increased or decreased.
Collapse
Affiliation(s)
- Manuela Meireles
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Eduardo Moura
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Porto, Portugal
| | | | - Celestino Santos-Buelga
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Susana Gonzalez-Manzano
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Montserrat Dueñas
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Nuno Mateus
- REQUIMTE/LAQV, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Ana Faria
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal.,REQUIMTE/LAQV, Faculty of Sciences, University of Porto, Porto, Portugal.,Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal
| | - Conceição Calhau
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal.,CINTESIS - Center for Research in Health Technologies and Information Systems, Faculty of Medicine, University of Porto, Porto, Portugal
| |
Collapse
|
26
|
Binding of alphaherpesvirus glycoprotein H to surface α4β1-integrins activates calcium-signaling pathways and induces phosphatidylserine exposure on the plasma membrane. mBio 2015; 6:e01552-15. [PMID: 26489864 PMCID: PMC4620472 DOI: 10.1128/mbio.01552-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Intracellular signaling connected to integrin activation is known to induce cytoplasmic Ca2+ release, which in turn mediates a number of downstream signals. The cellular entry pathways of two closely related alphaherpesviruses, equine herpesviruses 1 and 4 (EHV-1 and EHV-4), are differentially regulated with respect to the requirement of interaction of glycoprotein H (gH) with α4β1-integrins. We show here that binding of EHV-1, but not EHV-4, to target cells resulted in a rapid and significant increase in cytosolic Ca2+ levels. EHV-1 expressing EHV-4 gH (gH4) in lieu of authentic gH1 failed to induce Ca2+ release, while EHV-4 with gH1 triggered significant Ca2+ release. Blocking the interaction between gH1 and α4β1-integrins, inhibiting phospholipase C (PLC) activation, or blocking binding of inositol 1,4,5-triphosphate (IP3) to its receptor on the endoplasmic reticulum (ER) abrogated Ca2+ release. Interestingly, phosphatidylserine (PS) was exposed on the plasma membrane in response to cytosolic calcium increase after EHV-1 binding through a scramblase-dependent mechanism. Inhibition of both Ca2+ release from the ER and scramblase activation blocked PS scrambling and redirected virus entry to the endocytic pathway, indicating that PS may play a role in facilitating virus entry directly at the plasma membrane. Herpesviruses are a large family of enveloped viruses that infect a wide range of hosts, causing a variety of diseases. These viruses have developed a number of strategies for successful entry into different cell types. We and others have shown that alphaherpesviruses, including EHV-1 and herpes simplex virus 1 (HSV-1), can route their entry pathway and do so by manipulation of cell signaling cascades to ensure viral genome delivery to nuclei. We show here that the interaction between EHV-1 gH and cellular α4β1-integrins is necessary to induce emptying of ER calcium stores, which induces phosphatidylserine exposure on the plasma membrane through a scramblase-dependent mechanism. This change in lipid asymmetry facilitates virus entry and might help fusion of the viral envelope at the plasma membrane. These findings will help to advance our understanding of herpesvirus entry mechanism and may facilitate the development of novel drugs that can be implemented for prevention of infection and disease.
Collapse
|
27
|
Kim MJ, Rah SY, An JH, Kurokawa K, Kim UH, Lee BL. Human anti-peptidoglycan-IgG-mediated opsonophagocytosis is controlled by calcium mobilization in phorbol myristate acetate-treated U937 cells. BMB Rep 2015; 48:36-41. [PMID: 24856825 PMCID: PMC4345640 DOI: 10.5483/bmbrep.2015.48.1.080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 04/30/2014] [Accepted: 04/30/2014] [Indexed: 12/11/2022] Open
Abstract
Recently, we demonstrated that human serum amyloid P component (SAP) specifically recognizes exposed bacterial peptidoglycan (PGN) of wall teichoic acid (WTA)-deficient Staphylococcus aureus ΔtagO mutant cells and then induces complement-independent phagocytosis. In our preliminary experiments, we found the existence of human serum immunoglobulins that recognize S. aureus PGN (anti-PGNIgGs), which may be involved in complement-dependent opsonophagocytosis against infected S. aureus cells. We assumed that purified serum anti-PGN-IgGs and S. aureus ΔtagO mutant cells are good tools to study the molecular mechanism of anti-PGN-IgG-mediated phagocytosis. Therefore, we tried to identify the intracellular molecule(s) that is involved in the anti-PGN-IgG-mediated phagocytosis using purified human serum anti-PGN-IgGs and different S. aureus mutant cells. Here, we show that anti-PGN-IgG-mediated phagocytosis in phorbol myristate acetate-treated U937 cells is mediated by Ca2(+) release from intracellular Ca2(+) stores and anti-PGN-IgG dependent Ca2(+) mobilization is controlled via a phospholipase Cγ-2-mediated pathway.
Collapse
Affiliation(s)
- Min Jung Kim
- The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea
| | - So-Young Rah
- Department of Biochemistry, Chonbuk National University Medical School, Jeonju 561-180, Korea
| | - Jang-Hyun An
- The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea
| | - Kenji Kurokawa
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Nagasaki 859-3298, Japan
| | - Uh-Hyun Kim
- Department of Biochemistry, Chonbuk National University Medical School, Jeonju 561-180, Korea
| | - Bok Luel Lee
- The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea
| |
Collapse
|
28
|
Min CH, Wang Y, Bae J, Han JH, Sohn UD. The Inhibitory Mechanism of Gentamicin on Electrical Field Stimulation Response in Rat Bladder Smooth Muscle. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2015; 19:473-8. [PMID: 26330761 PMCID: PMC4553408 DOI: 10.4196/kjpp.2015.19.5.473] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/27/2015] [Accepted: 07/31/2015] [Indexed: 11/15/2022]
Abstract
To see the inhibitory mechanism of gentamicin in response to electrical field stimulation (EFS) using the rat bladder smooth muscle, atropine or guanethidine was treated but had no effect. Methylsergide, a non-selective 5-HT1, 5-HT2 receptor antagonist was also treated but had on effect. Kinase inhibitors, such as chelerythrine (PKC inhibitor), ML-9 (MLCK inhibitor), or Y27632 (rho kinase inhibitor) were pretreated before gentamicin treatment, but did not have effect. For U73122, a phospholipase C (PLC) inhibitor however, the inhibitory effect to gentamicin was significantly attenuated in all frequencies given by the EFS. Therefore gentamicin induced inhibitory effect on EFS response in rat bladder smooth muscle was not mediated by the activation of adrenergic, cholinergic, or serotonergic receptor. The inhibition of gentamicin might be mediated through the PLC dependent pathway, but not through the PKC, MLCK or rho kinase dependent pathway.
Collapse
Affiliation(s)
- Chang Ho Min
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - YiYi Wang
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Jinhyung Bae
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Jung Hoon Han
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Uy Dong Sohn
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| |
Collapse
|
29
|
Phosphoinositide dynamics in the postsynaptic membrane compartment: Mechanisms and experimental approach. Eur J Cell Biol 2015; 94:401-14. [DOI: 10.1016/j.ejcb.2015.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
30
|
Kamato D, Thach L, Bernard R, Chan V, Zheng W, Kaur H, Brimble M, Osman N, Little PJ. Structure, Function, Pharmacology, and Therapeutic Potential of the G Protein, Gα/q,11. Front Cardiovasc Med 2015; 2:14. [PMID: 26664886 PMCID: PMC4671355 DOI: 10.3389/fcvm.2015.00014] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/11/2015] [Indexed: 11/19/2022] Open
Abstract
G protein coupled receptors (GPCRs) are one of the major classes of cell surface receptors and are associated with a group of G proteins consisting of three subunits termed alpha, beta, and gamma. G proteins are classified into four families according to their α subunit; Gαi, Gαs, Gα12/13, and Gαq. There are several downstream pathways of Gαq of which the best known is upon activation via guanosine triphosphate (GTP), Gαq activates phospholipase Cβ, hydrolyzing phosphatidylinositol 4,5-biphosphate into diacylglycerol and inositol triphosphate and activating protein kinase C and increasing calcium efflux from the endoplasmic reticulum. Although G proteins, in particular, the Gαq/11 are central elements in GPCR signaling, their actual roles have not yet been thoroughly investigated. The lack of research of the role on Gαq/11 in cell biology is partially due to the obscure nature of the available pharmacological agents. YM-254890 is the most useful Gαq-selective inhibitor with antiplatelet, antithrombotic, and thrombolytic effects. YM-254890 inhibits Gαq signaling pathways by preventing the exchange of guanosine diphosphate for GTP. UBO-QIC is a structurally similar compound to YM-254890, which can inhibit platelet aggregation and cause vasorelaxation in rats. Many agents are available for the study of signaling downstream of Gαq/11. The role of G proteins could potentially represent a novel therapeutic target. This review will explore the range of pharmacological and molecular tools available for the study of the role of Gαq/11 in GPCR signaling.
Collapse
Affiliation(s)
- Danielle Kamato
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| | - Lyna Thach
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| | - Rebekah Bernard
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| | - Vincent Chan
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| | - Wenhua Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre , Guangzhou , China ; Faculty of Health Sciences, University of Macau , Macau , China
| | - Harveen Kaur
- Department of Chemistry, University of Auckland , Auckland , New Zealand
| | - Margaret Brimble
- Department of Chemistry, University of Auckland , Auckland , New Zealand
| | - Narin Osman
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| | - Peter J Little
- Discipline of Pharmacy, Diabetes Complications Group, School of Medical Sciences, Health Innovations Research Institute, RMIT University , Bundoora, VIC , Australia
| |
Collapse
|
31
|
Michel MC, Seifert R. Selectivity of pharmacological tools: implications for use in cell physiology. A review in the theme: Cell signaling: proteins, pathways and mechanisms. Am J Physiol Cell Physiol 2015; 308:C505-20. [PMID: 25631871 DOI: 10.1152/ajpcell.00389.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 01/24/2015] [Indexed: 01/08/2023]
Abstract
Pharmacological inhibitors are frequently used to identify the receptors, receptor subtypes, and associated signaling pathways involved in physiological cell responses. Based on the effects of such inhibitors conclusions are drawn about the involvement of their assumed target or lack thereof. While such inhibitors can be useful tools for a better physiological understanding, their uncritical use can lead to incorrect conclusions. This article reviews the concept of inhibitor selectivity and its implication for cell physiology. Specifically, we discuss the implications of using inhibitor vs. activator approaches, issues of direct vs. indirect pathway modulation, implications of inverse agonism and biased signaling, and those of orthosteric vs. allosteric, competitive vs. noncompetitive, and reversible vs. irreversible inhibition. Additional problems can result from inconsistent estimates of inhibitor potency and differences in potency between cell-free systems and intact cells. These concepts are illustrated by several examples of inhibitors displaying affinity for related but distinct targets or even unrelated targets. Of note, many of the issues being addressed are also applicable to genetic inhibition strategies. The main practical conclusion following from these concepts is that investigators should be critical in the choice of inhibitor, its concentrations, and its mode of application. When this advice is adhered to, small-molecule pharmacological inhibitors can be important experimental tools in the hand of physiologists.
Collapse
Affiliation(s)
- Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany; and
| | - Roland Seifert
- Department of Pharmacology, Hannover Medical School, Hannover, Germany
| |
Collapse
|
32
|
Kalachova T, Kravets V, Zachowski A, Ruelland E. Importance of phosphoinositide-dependent signaling pathways in the control of gene expression in resting cells and in response to phytohormones. PLANT SIGNALING & BEHAVIOR 2015; 10:e1019983. [PMID: 26039482 PMCID: PMC4623109 DOI: 10.1080/15592324.2015.1019983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 02/12/2015] [Accepted: 02/12/2015] [Indexed: 05/20/2023]
Abstract
"Phosphoinositide" refers to phosphorylated forms of phosphatidylinositol, including phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate. Both of these molecules could be in vivo substrates of plant phospholipase C. These phosphoinositides can also be biologically active "per se," by directly binding to proteins and thus altering their location and/or activity. The use of pharmacological agents in Arabidopsis suspension cells allowed us to identify genes whose expression was positively or negatively controlled, in the basal state, by products of phosphoinositide-dependent phospholipase C. In this basal state, it seems that no genes exhibit a phosphoinositide-dependent expression "per se." However, many genes whose expression is altered in the presence of phospholipase C inhibitors appeared to be responsive to salicylic acid. This allowed us to show that salicylic acid acts both by increasing the phosphoinositide pool and by inhibiting the phospholipase C. In response to salicylic acid it is possible to identify genes whose expression is controlled by products of PI-PLC, but also genes whose expression is controlled by phosphoinositides "per se." Our data highlight the importance of phosphoinositide-dependent pathways in gene expression in resting cells and in response to phytohormones.
Collapse
Key Words
- Arabidopsis cells in suspension
- DAG, diacylglycerol (DAG); PA, phosphatidic acid; PI, Phosphatidylinositol; PI-4-P, phosphatidylinositol-4-phosphate; PI4K, PI-4-kinase; PI-4, 5-P2, phosphatidylinositol-4, 5-bisphosphate; PI-PLC, phosphoinositide dependent-phospholipases C; PLD, phosphol
- diacylglycerol kinase
- phosphatidylinositol-4-kinase
- phosphoinositide
- phospholipase
- salicylic acid
- transcriptomic
Collapse
Affiliation(s)
- Tetiana Kalachova
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement; Paris, France; Centre National de la Recherche Scientifique; Institut d'Ecologie et des Sciences de l'Environnement; Paris, France
- Institute of Bioorganic Chemistry and Petrochemistry; National Academy of Sciences; Kyiv, Ukraine
| | - Volodymyr Kravets
- Institute of Bioorganic Chemistry and Petrochemistry; National Academy of Sciences; Kyiv, Ukraine
| | - Alain Zachowski
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement; Paris, France; Centre National de la Recherche Scientifique; Institut d'Ecologie et des Sciences de l'Environnement; Paris, France
| | - Eric Ruelland
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement; Paris, France; Centre National de la Recherche Scientifique; Institut d'Ecologie et des Sciences de l'Environnement; Paris, France
- Correspondence to: Eric Ruelland;
| |
Collapse
|
33
|
Mori MX, Inoue R. New experimental trends for phosphoinositides research on ion transporter/channel regulation. J Pharmacol Sci 2014; 126:186-97. [PMID: 25367262 DOI: 10.1254/jphs.14r14cp] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Phosphoinositides(4,5)-bisphosphates [PI(4,5)P2] critically controls membrane excitability, the disruption of which leads to pathophysiological states. PI(4,5)P2 plays a primary role in regulating the conduction and gating properties of ion channels/transporters, through electrostatic and hydrophobic interactions that allow direct associations. In recent years, the development of many molecular tools have brought deep insights into the mechanisms underlying PI(4,5)P2-mediated regulation. This review summarizes the methods currently available to manipulate the cell membrane PI(4,5)P2 level including pharmacological interventions as well as newly designed molecular tools. We concisely introduce materials and experimental designs suitable for the study of PI(4,5)P2-mediated regulation of ion-conducting molecules, in order to assist researchers who are interested in this area. It is our further hope that the knowledge introduced in this review will help to promote our understanding about the pathology of diseases such as cardiac arrhythmias, bipolar disorders, and Alzheimer's disease which are somehow associated with a disruption of PI(4,5)P2 metabolism.
Collapse
Affiliation(s)
- Masayuki X Mori
- Department of Synthetic Chemistry and Biological Chemistry, School of Engineering, Kyoto University, Japan
| | | |
Collapse
|
34
|
Bolnick JM, Karana R, Chiang PJ, Kilburn BA, Romero R, Diamond MP, Smith SM, Armant DR. Apoptosis of alcohol-exposed human placental cytotrophoblast cells is downstream of intracellular calcium signaling. Alcohol Clin Exp Res 2014; 38:1646-53. [PMID: 24889927 DOI: 10.1111/acer.12417] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 02/22/2014] [Indexed: 11/26/2022]
Abstract
BACKGROUND Apoptosis is induced by ethanol (EtOH) in human placental trophoblast cells, possibly disrupting placentation and contributing to intrauterine growth restriction in fetal alcohol spectrum disorder (FASD). EtOH induces programmed cell death in several embryonic tissues by raising intracellular Ca(2+) . Therefore, the role of Ca(2+) signaling in EtOH-induced apoptosis was examined using human first trimester cytotrophoblast cell lines, examining the hypothesis that apoptosis is dependent on intracellular Ca(2+) signaling. METHODS Using HTR-8/SVneo and SW.71 cytotrophoblast cell lines, real-time intracellular Ca(2+) concentration was monitored by fluo-4 epifluorescence microscopy and apoptosis was assessed by flow cytometry of cells fluorescently labeled for DNA fragmentation (TUNEL) and annexin V binding. RESULTS Intracellular Ca(2+) concentrations increased synchronously in all cells within 10 seconds of exposure to 50 mM EtOH, but not at lower EtOH concentrations (10 to 25 mM) incapable of inducing apoptosis. Trophoblast cells treated with inhibitors of Ca(2+) signaling (BAPTA-AM, U73122, xestospongin D, BAPTA, SKF-96365) produced no intracellular Ca(2+) transients after exposure to 50 mM EtOH and were protected from cell death induced by EtOH. CONCLUSIONS EtOH-induced apoptosis in human cytotrophoblast cells, identified by DNA fragmentation and externalized phosphatidylserine, was dependent upon Ca(2+) signaling. Both intracellular Ca(2+) mobilization and extracellular Ca(2+) influx were required, as well as phosphatidylinositol signaling. Inhibition by SKF-96365 suggests that the capacitative Ca(2+) entry mechanism that utilizes TRPC channels was activated by EtOH. Apoptosis occurs downstream of Ca(2+) signaling in trophoblasts and may contribute to placental insufficiency and poor fetal growth associated with FASD.
Collapse
Affiliation(s)
- Jay M Bolnick
- Department of Obstetrics and Gynecology, Wayne State University, C.S. Mott Center for Human Growth and Development, Detroit, Michigan
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Ruelland E, Pokotylo I, Djafi N, Cantrel C, Repellin A, Zachowski A. Salicylic acid modulates levels of phosphoinositide dependent-phospholipase C substrates and products to remodel the Arabidopsis suspension cell transcriptome. FRONTIERS IN PLANT SCIENCE 2014; 5:608. [PMID: 25426125 PMCID: PMC4227474 DOI: 10.3389/fpls.2014.00608] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/19/2014] [Indexed: 05/05/2023]
Abstract
Basal phosphoinositide-dependent phospholipase C (PI-PLC) activity controls gene expression in Arabidopsis suspension cells and seedlings. PI-PLC catalyzes the production of phosphorylated inositol and diacylglycerol (DAG) from phosphoinositides. It is not known how PI-PLC regulates the transcriptome although the action of DAG-kinase (DGK) on DAG immediately downstream from PI-PLC is responsible for some of the regulation. We previously established a list of genes whose expression is affected in the presence of PI-PLC inhibitors. Here this list of genes was used as a signature in similarity searches of curated plant hormone response transcriptome data. The strongest correlations obtained with the inhibited PI-PLC signature were with salicylic acid (SA) treatments. We confirm here that in Arabidopsis suspension cells SA treatment leads to an increase in phosphoinositides, then demonstrate that SA leads to a significant 20% decrease in phosphatidic acid, indicative of a decrease in PI-PLC products. Previous sets of microarray data were re-assessed. The SA response of one set of genes was dependent on phosphoinositides. Alterations in the levels of a second set of genes, mostly SA-repressed genes, could be related to decreases in PI-PLC products that occur in response to SA action. Together, the two groups of genes comprise at least 40% of all SA-responsive genes. Overall these two groups of genes are distinct in the functional categories of the proteins they encode, their promoter cis-elements and their regulation by DGK or phospholipase D. SA-regulated genes dependent on phosphoinositides are typical SA response genes while those with an SA response that is possibly dependent on PI-PLC products are less SA-specific. We propose a model in which SA inhibits PI-PLC activity and alters levels of PI-PLC products and substrates, thereby regulating gene expression divergently.
Collapse
Affiliation(s)
- Eric Ruelland
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- *Correspondence: Eric Ruelland, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Université Paris-Est Créteil, Faculté des Sciences, 61 Avenue du Général de Gaulle, 94010 Créteil, France e-mail:
| | - Igor Pokotylo
- Molecular Mechanisms of Plant Cell Regulation, Institute of Bioorganic Chemistry and Petrochemistry, National Academy of SciencesKyiv, Ukraine
| | - Nabila Djafi
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
| | - Catherine Cantrel
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
| | - Anne Repellin
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
| | - Alain Zachowski
- Université Paris-Est Créteil, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7618, Institut d'Ecologie et des Sciences de l'Environnement de ParisCréteil, France
| |
Collapse
|
36
|
PI-PLC: Phosphoinositide-Phospholipase C in Plant Signaling. SIGNALING AND COMMUNICATION IN PLANTS 2014. [DOI: 10.1007/978-3-642-42011-5_2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
37
|
Djafi N, Vergnolle C, Cantrel C, Wietrzyñski W, Delage E, Cochet F, Puyaubert J, Soubigou-Taconnat L, Gey D, Collin S, Balzergue S, Zachowski A, Ruelland E. The Arabidopsis DREB2 genetic pathway is constitutively repressed by basal phosphoinositide-dependent phospholipase C coupled to diacylglycerol kinase. FRONTIERS IN PLANT SCIENCE 2013; 4:307. [PMID: 23964284 PMCID: PMC3737466 DOI: 10.3389/fpls.2013.00307] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 07/22/2013] [Indexed: 05/02/2023]
Abstract
Phosphoinositide-dependent phospholipases C (PI-PLCs) are activated in response to various stimuli. They utilize substrates provided by type III-Phosphatidylinositol-4 kinases (PI4KIII) to produce inositol triphosphate and diacylglycerol (DAG) that is phosphorylated into phosphatidic acid (PA) by DAG-kinases (DGKs). The roles of PI4KIIIs, PI-PLCs, and DGKs in basal signaling are poorly understood. We investigated the control of gene expression by basal PI-PLC pathway in Arabidopsis thaliana suspension cells. A transcriptome-wide analysis allowed the identification of genes whose expression was altered by edelfosine, 30 μM wortmannin, or R59022, inhibitors of PI-PLCs, PI4KIIIs, and DGKs, respectively. We found that a gene responsive to one of these molecules is more likely to be similarly regulated by the other two inhibitors. The common action of these agents is to inhibit PA formation, showing that basal PI-PLCs act, in part, on gene expression through their coupling to DGKs. Amongst the genes up-regulated in presence of the inhibitors, were some DREB2 genes, in suspension cells and in seedlings. The DREB2 genes encode transcription factors with major roles in responses to environmental stresses, including dehydration. They bind to C-repeat motifs, known as Drought-Responsive Elements that are indeed enriched in the promoters of genes up-regulated by PI-PLC pathway inhibitors. PA can also be produced by phospholipases D (PLDs). We show that the DREB2 genes that are up-regulated by PI-PLC inhibitors are positively or negatively regulated, or indifferent, to PLD basal activity. Our data show that the DREB2 genetic pathway is constitutively repressed in resting conditions and that DGK coupled to PI-PLC is active in this process, in suspension cells and seedlings. We discuss how this basal negative regulation of DREB2 genes is compatible with their stress-triggered positive regulation.
Collapse
Affiliation(s)
- Nabila Djafi
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Chantal Vergnolle
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Catherine Cantrel
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | | | - Elise Delage
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Françoise Cochet
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Juliette Puyaubert
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Ludivine Soubigou-Taconnat
- Unité de Recherche en Biologie Végétale, UMR INRA 1165, Université d'Evry Val d'Essonne, ERL CNRS 8196Evry Cedex, France
| | - Delphine Gey
- Unité de Recherche en Biologie Végétale, UMR INRA 1165, Université d'Evry Val d'Essonne, ERL CNRS 8196Evry Cedex, France
| | - Sylvie Collin
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Sandrine Balzergue
- Unité de Recherche en Biologie Végétale, UMR INRA 1165, Université d'Evry Val d'Essonne, ERL CNRS 8196Evry Cedex, France
| | - Alain Zachowski
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| | - Eric Ruelland
- Physiologie Cellulaire et Moléculaire des Plantes, CNRS EAC7180Paris, France
- Physiologie Cellulaire et Moléculaire des Plantes, UPMC-Univ Paris06 UR5Paris, France
| |
Collapse
|
38
|
Abstract
The objective of this study was to elucidate the signalling pathways initiated by cAMP once inside the Xenopus laevis oocyte, where it triggers and maintains vitellogenin endocytic uptake. Our results showed the presence of Xepac transcripts at all stages of oogenesis and we demonstrated that a cAMP analogue that exclusively activates Xepac, 8-CPT, was able to rescue the endocytic activity in oocytes with uncoupled gap junctions. Inhibition experiments for the IP3/Ca2+ signalling pathway showed either a complete inhibition or a significant reduction of the vitellogenic process. These results were confirmed with the rescue capability of the A-23187 ionophore in those oocyte batches in which the IP3/Ca2+ pathway was inhibited. Taking our findings into account, we propose that the cAMP molecule binds Xepac protein enabling it to activate the IP3/Ca2+ pathway, which is necessary to start and maintain X. laevis vitellogenin uptake.
Collapse
|
39
|
Saha K, Kim ST, Yan B, Miranda OR, Alfonso FS, Shlosman D, Rotello VM. Surface functionality of nanoparticles determines cellular uptake mechanisms in mammalian cells. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:300-305. [PMID: 22972519 PMCID: PMC4070423 DOI: 10.1002/smll.201201129] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 07/04/2012] [Indexed: 04/14/2023]
Abstract
Nanoparticles (NPs) are versatile scaffolds for numerous biomedical applications including drug delivery and bioimaging. The surface functionality of NPs essentially dictates intracellular NP uptake and controls their therapeutic action. Using several pharmacological inhibitors, it is demonstrated that the cellular uptake mechanisms of cationic gold NPs in both cancer (HeLa) and normal cells (MCF10A) strongly depend on the NP surface monolayer, and mostly involve caveolae and dynamin-dependent pathways as well as specific cell surface receptors (scavenger receptors). Moreover, these NPs show different uptake mechanisms in cancer and normal cells, providing an opportunity to develop NPs with improved selectivity for delivery applications.
Collapse
|
40
|
Dallal Bashi Z, Rimmer SR, Khachatourians GG, Hegedus DD. Factors governing the regulation of Sclerotinia sclerotiorum cutinase A and polygalacturonase 1 during different stages of infection. Can J Microbiol 2012; 58:605-16. [PMID: 22524557 DOI: 10.1139/w2012-031] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sclerotinia sclerotiorum releases hydrolytic enzymes that sequentially degrade the plant cuticle, middle lamellae, and primary and secondary cell walls. The cuticle was found to be a barrier to S. sclerotiorum infection, as leaves stripped of epicuticular wax were more rapidly colonized. Consequently, the factors affecting the regulation of genes encoding polygalacturonase 1 (SsPG1) and a newly identified cutinase (SsCUTA) were examined. In vitro, SsCutA transcripts were detected within 1 h postinoculation of leaves, and expression was primarily governed by contact of mycelia with solid surfaces. Expression of SsPg1 was moderately induced by contact with solid surfaces including the leaf, and expression was restricted to the expanding margin of the lesion as the infection progressed. SsPg1 expression was induced by carbohydrate starvation but repressed by galacturonic acid. Glucose supported a basal level of SsPg1 expression but accentuated expression when provided to mycelia used to inoculate leaves. These observations were contrary to earlier reports indicating that glucose repressed SsPg1 expression while galacturonic acid induced expression. Pharmacological studies showed that disruption of calcium signalling affected SsCutA and SsPg1 expression and decreased S. sclerotiorum virulence, whereas elevated cAMP levels reduced virulence without affecting gene expression. The mechanisms involved in coordinating the expression of S. sclerotiorum hydrolytic enzymes throughout the various stages of the infection are discussed.
Collapse
Affiliation(s)
- Zafer Dallal Bashi
- Agriculture and Agri-Food Canada, 107 Science Place Saskatoon, SK S7N 0X2, Canada
| | | | | | | |
Collapse
|
41
|
The CatSper channel: a polymodal chemosensor in human sperm. EMBO J 2012; 31:1654-65. [PMID: 22354039 DOI: 10.1038/emboj.2012.30] [Citation(s) in RCA: 174] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 01/18/2012] [Indexed: 01/10/2023] Open
Abstract
The sperm-specific CatSper channel controls the intracellular Ca(2+) concentration ([Ca(2+)](i)) and, thereby, the swimming behaviour of sperm. In humans, CatSper is directly activated by progesterone and prostaglandins-female factors that stimulate Ca(2+) influx. Other factors including neurotransmitters, chemokines, and odorants also affect sperm function by changing [Ca(2+)](i). Several ligands, notably odorants, have been proposed to control Ca(2+) entry and motility via G protein-coupled receptors (GPCRs) and cAMP-signalling pathways. Here, we show that odorants directly activate CatSper without involving GPCRs and cAMP. Moreover, membrane-permeable analogues of cyclic nucleotides that have been frequently used to study cAMP-mediated Ca(2+) signalling also activate CatSper directly via an extracellular site. Thus, CatSper or associated protein(s) harbour promiscuous binding sites that can host various ligands. These results contest current concepts of Ca(2+) signalling by GPCR and cAMP in mammalian sperm: ligands thought to activate metabotropic pathways, in fact, act via a common ionotropic mechanism. We propose that the CatSper channel complex serves as a polymodal sensor for multiple chemical cues that assist sperm during their voyage across the female genital tract.
Collapse
|
42
|
Petersen OH, Gerasimenko OV, Tepikin AV, Gerasimenko JV. Aberrant Ca(2+) signalling through acidic calcium stores in pancreatic acinar cells. Cell Calcium 2011; 50:193-9. [PMID: 21435718 DOI: 10.1016/j.ceca.2011.02.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 02/25/2011] [Accepted: 02/27/2011] [Indexed: 12/13/2022]
Abstract
Pancreatic acinar cells possess a very large Ca(2+) store in the endoplasmic reticulum, but also have extensive acidic Ca(2+) stores. Whereas the endoplasmic reticulum is principally located in the baso-lateral part of the cells, although with extensions into the granular area, the acidic stores are exclusively present in the apical part. The two types of stores can be differentiated pharmacologically because the endoplasmic reticulum accumulates Ca(2+) via SERCA pumps, whereas the acidic pools require functional vacuolar H(+) pumps in order to maintain a high intra-organellar Ca(2+) concentration. The human disease acute pancreatitis is initiated by trypsinogen activation in the apical pole and this is mostly due to either complications arising from gall bladder stones or excessive alcohol consumption. Attention has therefore been focussed on assessing the acute effects of bile acids as well as alcohol metabolites. The evidence accumulated so far indicates that bile acids and fatty acid ethyl esters - the non-oxidative products of alcohol and fatty acids - exert their pathological effects primarily by excessive Ca(2+) release from the acidic stores. This occurs by opening of the very same release channels that are also responsible for normal stimulus-secretion coupling, namely inositol trisphosphate and ryanodine receptors. The inositol trisphosphate receptors are of particular importance and the results of gene deletion experiments indicate that the fatty acid ethyl esters mainly utilize sub-types 2 and 3.
Collapse
Affiliation(s)
- O H Petersen
- MRC Secretory Control Group, Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, Wales, UK.
| | | | | | | |
Collapse
|
43
|
Jiang ZL, Ripamonte P, Buratini J, Portela VM, Price CA. Fibroblast growth factor-2 regulation of Sprouty and NR4A genes in bovine ovarian granulosa cells. J Cell Physiol 2011; 226:1820-7. [PMID: 21506113 DOI: 10.1002/jcp.22509] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Fibroblast growth factors (FGFs) alter ovarian function, at least in part by inhibiting steroid hormone secretion and affecting survival of granulosa cells. The mechanism of action of FGFs in ovarian follicle cells is largely unknown; in the present study we identified the major pathways used by FGF2 in non-luteinizing granulosa cells cultured under serum-free conditions. FGF2 increased abundance of mRNA encoding SPRY1, 2, and 4, but not SPRY3. Common pathways employed by FGF2 in the regulation of SPRY1, 2, and 4, as demonstrated by immunoblot and inhibitor studies, included ERK1/2 and Akt signaling. In contrast, PKC activation was necessary for FGF2-stimulated expression of SPRY1 and 4, but not for SPRY2. Intracellular calcium flux is critical and sufficient for SPRY2 expression, but not for SPRY1 and 4. We also identified the orphan nuclear receptor NR4A1 as a potential early response gene in FGF2 signaling, whose expression, like that of SPRY2, is critically dependent on calcium signaling. Together, these data identify FGF2-target genes in follicular granulosa cells, and demonstrate alternative pathway use for the differential control of SPRY genes.
Collapse
Affiliation(s)
- Z L Jiang
- College of Animal Science and Technology, Northwestern A&F University, Yangling, Shaanxi, China
| | | | | | | | | |
Collapse
|
44
|
Zhao H, Kinch DC, Simasko SM. Pharmacological investigations of the cellular transduction pathways used by cholecystokinin to activate nodose neurons. Auton Neurosci 2011; 164:20-6. [PMID: 21664195 DOI: 10.1016/j.autneu.2011.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 05/18/2011] [Accepted: 05/19/2011] [Indexed: 11/25/2022]
Abstract
Cholecystokinin (CCK) directly activates vagal afferent neurons resulting in coordinated gastrointestinal functions and satiation. In vitro, the effects of CCK on dissociated vagal afferent neurons are mediated via activation of the vanilloid family of transient receptor potential (TRPV) cation channels leading to membrane depolarization and an increase in cytosolic calcium. However, the cellular transduction pathway(s) involved in this process between CCK receptors and channel opening have not been identified. To address this question, we monitored CCK-induced cytosolic calcium responses in dissociated nodose neurons from rat in the presence or absence of reagents that interact with various intracellular signaling pathways. We found that the phospholipase C (PLC) inhibitor U-73122 significantly attenuated CCK-induced responses, whereas the inactive analog U-73433 had no effect. Responses to CCK were also cross-desensitized by a brief pretreatment with m-3M3FBS, a PLC stimulator. Together these observations strongly support the participation of PLC in the effects of CCK on vagal afferent neurons. In contrast, pharmacological antagonism of phospholipase A(2), protein kinase A, and phosphatidylinositol 3-kinase revealed that they are not critical in the CCK-induced calcium response in nodose neurons. Further investigations of the cellular pathways downstream of PLC showed that neither protein kinase C (PKC) nor generation of diacylglycerol (DAG) or release of calcium from intracellular stores participates in the response to CCK. These results suggest that alteration of membrane phosphatidylinositol 4,5-bisphosphate (PIP(2)) content by PLC activity mediates CCK-induced calcium response and that this pathway may underlie the vagally-mediated actions of CCK to induce satiation and alter gastrointestinal functions.
Collapse
Affiliation(s)
- Huan Zhao
- Program in Neuroscience, Dept of Veterinary and Comparative Anatomy, Pharmacology, and Physiology, Washington State University, Pullman, WA 99164, USA.
| | | | | |
Collapse
|
45
|
Raabe AC, Wengelnik K, Billker O, Vial HJ. Multiple roles for Plasmodium berghei phosphoinositide-specific phospholipase C in regulating gametocyte activation and differentiation. Cell Microbiol 2011; 13:955-66. [PMID: 21518218 PMCID: PMC3132445 DOI: 10.1111/j.1462-5822.2011.01591.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Critical events in the life cycle of malaria parasites are controlled by calcium-dependent signalling cascades, yet the molecular mechanisms of calcium release remain poorly understood. The synchronized development of Plasmodium berghei gametocytes relies on rapid calcium release from internal stores within 10 s of gametocytes being exposed to mosquito-derived xanthurenic acid (XA). Here we addressed the function of phosphoinositide-specific phospholipase C (PI-PLC) for regulating gametocyte activation. XA triggered the hydrolysis of PIP2 and the production of the secondary messenger IP3 in gametocytes. Both processes were selectively blocked by a PI-PLC inhibitor, which also reduced the early Ca2+ signal. However, microgametocyte differentiation into microgametes was blocked even when the inhibitor was added up to 5 min after activation, suggesting a requirement for PI-PLC beyond the early mobilization of calcium. In contrast, inhibitors of calcium release through ryanodine receptor channels were active only during the first minute of gametocyte activation. Biochemical determination of PI-PLC activity was confirmed using transgenic parasites expressing a fluorescent PIP2/IP3 probe that translocates from the parasite plasmalemma to the cytosol upon cell activation. Our study revealed a complex interdependency of Ca2+ and PI-PLC activity, with PI-PLC being essential throughout gamete formation, possibly explaining the irreversibility of this process.
Collapse
Affiliation(s)
- Andreas C Raabe
- UMR5235, CNRS-Université Montpellier 2, Place Eugène Bataillon, Montpellier cedex 5, France
| | | | | | | |
Collapse
|
46
|
Moustafa A, Sakamoto KQ, Habara Y. A fundamental role for NO-PLC signaling pathway in mediating intracellular Ca2+ oscillation in pancreatic acini. Nitric Oxide 2011; 24:139-50. [DOI: 10.1016/j.niox.2011.02.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 01/21/2011] [Accepted: 02/02/2011] [Indexed: 11/17/2022]
|
47
|
Lo Vasco VR, Fabrizi C, Panetta B, Fumagalli L, Cocco L. Expression pattern and sub-cellular distribution of phosphoinositide specific phospholipase C enzymes after treatment with U-73122 in rat astrocytoma cells. J Cell Biochem 2010; 110:1005-12. [PMID: 20564200 DOI: 10.1002/jcb.22614] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Phosphoinositide specific phospholipase C (PI-PLC) enzymes interfere with the metabolism of inositol phospholipids (PI), molecules involved in signal transduction, a complex process depending on various components. Many evidences support the hypothesis that, in the glia, isoforms of PI-PLC family display different expression and/or sub cellular distribution under non-physiological conditions such as the rat astrocytes activation during neurodegeneration, the tumoural progression of some neoplasms and the inflammatory cascade activation after lipopolysaccharide administration, even if their role remains not completely elucidated. Treatment of a cultured established glioma cell line (C6 rat astrocytoma cell line) induces a modification in the pattern of expression and of sub cellular distribution of PI-PLCs compared to untreated cells. Special attention require PI-PLC beta3 and PI-PLC gamma2 isoforms, whose expression and sub cellular localization significantly differ after U-73122 treatment. The meaning of these modifications is unclear, also because the use of this N-aminosteroid compound remains controversial, inasmuch it has further actions which might contribute to the global effect recorded on the treated cells.
Collapse
Affiliation(s)
- Vincenza Rita Lo Vasco
- Department of Otorinolaringoiatria, Audiologia and Foniatria "G. Ferreri", Policlinico Umberto I, Rome, Italy.
| | | | | | | | | |
Collapse
|
48
|
Hollywood MA, Sergeant GP, Thornbury KD, McHale NG. The PI-PLC inhibitor U-73122 is a potent inhibitor of the SERCA pump in smooth muscle. Br J Pharmacol 2010; 160:1293-4. [PMID: 20590620 DOI: 10.1111/j.1476-5381.2010.00795.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In this issue MacMillan and McCarron in 2010 demonstrated that the phospholipase C (PLC) inhibitor U-73122 can potently inhibit Ca(2+) release from isolated smooth muscle cells independent of its effect on PLC. Their data suggest that the PLC inhibitor can block the sarcoplasmic/endoplasmic reticulum calcium ATPase pump in smooth muscle and cast doubt on the reliability of U-73122 as the main pharmacological tool to assess the role of the phosphotidyl inositol-PLC pathway in cellular signalling.
Collapse
Affiliation(s)
- M A Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Co. Louth, Ireland.
| | | | | | | |
Collapse
|
49
|
Burgdorf C, Schäfer U, Richardt G, Kurz T. U73122, an aminosteroid phospholipase C inhibitor, is a potent inhibitor of cardiac phospholipase D by a PIP2-dependent mechanism. J Cardiovasc Pharmacol 2010; 55:555-9. [PMID: 20179606 DOI: 10.1097/fjc.0b013e3181d8bec5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The aminosteroid 1-[6-({17beta-3-methoxyestra-1,3,5(10)-trien-17-yl}amino)hexyl]-1H-pyrrole-2,5-dione (U73122) has been extensively used as a pharmacologic inhibitor of phospholipase C (PLC). The inhibitory effect of U73122 on PLC activity is most likely the result of decreased availability of phosphatidylinositol 4,5-bisphosphate (PIP2), the substrate of the PLC signal transduction pathway, rather than direct inhibition of the enzyme. PIP2 is a phospholipid with pleiotropic cellular functions, including a pivotal role in regulating cardiac phospholipase D (PLD) signal transduction. Here, we hypothesized that U73122 acts as an inhibitor of cardiac PLD activity by interference with PIP2. U73122 concentration-dependently inhibited PLD activity in rat myocardial membranes. The inhibitory effect of U73122 was significantly attenuated when assayed on solubilized PLD activity and was completely restored if solubilized PLD activity was assayed in the presence of PIP2. U73122 had no inhibitory effect on purified PLD indicating that the substance does not interact with PLD directly. These data highlight a mechanism of action of U73122 as an inhibitor of myocardial PLD by interaction with PIP2 as a cofactor for optimal PLD activity. Hence, studies using U73122 as a specific inhibitor of PLC have to take into account that PLD may be involved in some of the effects ascribed to PLC.
Collapse
Affiliation(s)
- Christof Burgdorf
- Department of Internal Medicine II, University Hospital Schleswig-Holstein, Lübeck, Germany.
| | | | | | | |
Collapse
|
50
|
The opening of maitotoxin-sensitive calcium channels induces the acrosome reaction in human spermatozoa: differences from the zona pellucida. Asian J Androl 2010; 13:159-65. [PMID: 20835262 DOI: 10.1038/aja.2010.80] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The acrosome reaction (AR), an absolute requirement for spermatozoa and egg fusion, requires the influx of Ca²(+) into the spermatozoa through voltage-dependent Ca²(+) channels and store-operated channels. Maitotoxin (MTx), a Ca²(+)-mobilizing agent, has been shown to be a potent inducer of the mouse sperm AR, with a pharmacology similar to that of the zona pellucida (ZP), possibly suggesting a common pathway for both inducers. Using recombinant human ZP3 (rhZP3), mouse ZP and two MTx channel blockers (U73122 and U73343), we investigated and compared the MTx- and ZP-induced ARs in human and mouse spermatozoa. Herein, we report that MTx induced AR and elevated intracellular Ca²(+) ([Ca²(+)](i)) in human spermatozoa, both of which were blocked by U73122 and U73343. These two compounds also inhibited the MTx-induced AR in mouse spermatozoa. In disagreement with our previous proposal, the AR triggered by rhZP3 or mouse ZP was not blocked by U73343, indicating that in human and mouse spermatozoa, the AR induction by the physiological ligands or by MTx occurred through distinct pathways. U73122, but not U73343 (inactive analogue), can block phospholipase C (PLC). Another PLC inhibitor, edelfosine, also blocked the rhZP3- and ZP-induced ARs. These findings confirmed the participation of a PLC-dependent signalling pathway in human and mouse zona protein-induced AR. Notably, edelfosine also inhibited the MTx-induced mouse sperm AR but not that of the human, suggesting that toxin-induced AR is PLC-dependent in mice and PLC-independent in humans.
Collapse
|