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Park SK, Sprague DJ, Rohr CM, Chulkov EG, Petrow I, Kumar S, Marchant JS. The anthelmintic meclonazepam activates a schistosome transient receptor potential channel. J Biol Chem 2024; 300:105528. [PMID: 38043794 PMCID: PMC10788528 DOI: 10.1016/j.jbc.2023.105528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 11/15/2023] [Accepted: 11/28/2023] [Indexed: 12/05/2023] Open
Abstract
Parasitic flatworms cause various clinical and veterinary infections that impart a huge burden worldwide. The most clinically impactful infection is schistosomiasis, a neglected tropical disease caused by parasitic blood flukes. Schistosomiasis is treated with praziquantel (PZQ), an old drug introduced over 40 years ago. New drugs are urgently needed, as while PZQ is broadly effective it suffers from several limitations including poor efficacy against juvenile worms, which may prevent it from being completely curative. An old compound that retains efficacy against juvenile worms is the benzodiazepine meclonazepam (MCLZ). However, host side effects caused by benzodiazepines preclude development of MCLZ as a drug and MCLZ lacks an identified parasite target to catalyze rational drug design for engineering out human host activity. Here, we identify a transient receptor potential ion channel of the melastatin subfamily, named TRPMMCLZ, as a parasite target of MCLZ. MCLZ potently activates Schistosoma mansoni TRPMMCLZ through engagement of a binding pocket within the voltage-sensor-like domain of the ion channel to cause worm paralysis, tissue depolarization, and surface damage. TRPMMCLZ reproduces all known features of MCLZ action on schistosomes, including a lower activity versus Schistosoma japonicum, which is explained by a polymorphism within this voltage-sensor-like domain-binding pocket. TRPMMCLZ is distinct from the TRP channel targeted by PZQ (TRPMPZQ), with both anthelmintic chemotypes targeting unique parasite TRPM paralogs. This advances TRPMMCLZ as a novel druggable target that could circumvent any target-based resistance emerging in response to current mass drug administration campaigns centered on PZQ.
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Affiliation(s)
- Sang-Kyu Park
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Daniel J Sprague
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA; Program in Chemical Biology, Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Claudia M Rohr
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Evgeny G Chulkov
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Ian Petrow
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Sushil Kumar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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Sprague DJ, Park SK, Gramberg S, Bauer L, Rohr CM, Chulkov EG, Smith E, Scampavia L, Spicer TP, Haeberlein S, Marchant JS. Target-based discovery of a broad spectrum flukicide. bioRxiv 2023:2023.09.22.559026. [PMID: 37790347 PMCID: PMC10542552 DOI: 10.1101/2023.09.22.559026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Diseases caused by parasitic flatworms impart a considerable healthcare burden worldwide. Many of these diseases - for example, the parasitic blood fluke infection, schistosomiasis - are treated with the drug praziquantel (PZQ). However, PZQ is ineffective against disease caused by liver flukes from the genus Fasciola. This is due to a single amino acid change within the target of PZQ, a transient receptor potential ion channel (TRPMPZQ), in Fasciola species. Here we identify benzamidoquinazolinone analogs that are active against Fasciola TRPMPZQ. Structure-activity studies define an optimized ligand (BZQ) that caused protracted paralysis and damage to the protective tegument of these liver flukes. BZQ also retained activity against Schistosoma mansoni comparable to PZQ and was active against TRPMPZQ orthologs in all profiled species of parasitic fluke. This broad spectrum activity was manifest as BZQ adopts a pose within the binding pocket of TRPMPZQ dependent on a ubiquitously conserved residue. BZQ therefore acts as a universal activator of trematode TRPMPZQ and a first-in-class, broad spectrum flukicide.
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Affiliation(s)
- Daniel J. Sprague
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Program in Chemical Biology, Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Sang-Kyu Park
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Svenja Gramberg
- BFS, Institute of Parasitology, Justus Liebig University Giessen, Schubertstr. 81, 35392, Giessen, Germany
| | - Lisa Bauer
- BFS, Institute of Parasitology, Justus Liebig University Giessen, Schubertstr. 81, 35392, Giessen, Germany
| | - Claudia M. Rohr
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Evgeny G. Chulkov
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Emery Smith
- UF Scripps Molecular Screening Center, Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL, 33458, USA
| | - Louis Scampavia
- UF Scripps Molecular Screening Center, Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL, 33458, USA
| | - Timothy P. Spicer
- UF Scripps Molecular Screening Center, Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL, 33458, USA
| | - Simone Haeberlein
- BFS, Institute of Parasitology, Justus Liebig University Giessen, Schubertstr. 81, 35392, Giessen, Germany
| | - Jonathan S. Marchant
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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Chulkov EG, Palygin O, Yahya NA, Park SK, Marchant JS. Electrophysiological characterization of a schistosome transient receptor potential channel activated by praziquantel. Int J Parasitol 2023; 53:415-425. [PMID: 36610556 PMCID: PMC10258134 DOI: 10.1016/j.ijpara.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/12/2022] [Accepted: 11/16/2022] [Indexed: 01/06/2023]
Abstract
Ion channels have proved to be productive targets for anthelmintic chemotherapy. One example is the recent discovery of a parasitic flatworm ion channel targeted by praziquantel (PZQ), the main clinical therapy used for treatment of schistosomiasis. The ion channel activated by PZQ - a transient receptor potential ion channel of the melastatin subfamily, named TRPMPZQ - is a Ca2+-permeable ion channel expressed in all parasitic flatworms that are PZQ-sensitive. However, little is currently known about the electrophysiological properties of this target that mediates the deleterious action of PZQ on many trematodes and cestodes. Here, we provide a detailed biophysical characterization of the properties of Schistosoma mansoni TRPMPZQ channel (Sm.TRPMPZQ) in response to PZQ. Single channel electrophysiological analysis demonstrated that Sm.TRPMPZQ when activated by PZQ is a non-selective, large conductance, voltage-insensitive cation channel that displays distinct properties from human TRPM paralogs. Sm.TRPMPZQ is Ca2+-permeable but does not require Ca2+ for channel gating in response to PZQ. TRPMPZQ from Schistosoma japonicum (Sj.TRPMPZQ) and Schistosoma haematobium (Sh.TRPMPZQ) displayed similar characteristics. Profiling Sm.TRPMPZQ responsiveness to PZQ has established a biophysical signature for this channel that will aid future investigation of endogenous TRPMPZQ activity, as well as analyses of endogenous and exogenous regulators of this novel, druggable antiparasitic target.
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Affiliation(s)
- Evgeny G Chulkov
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Oleg Palygin
- Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Nawal A Yahya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA; Department of Pharmacology, University of Minnesota Medical School, 312 Church St. SE, Minneapolis, MN 55455, USA
| | - Sang-Kyu Park
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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Chulkov EG, Isaeva E, Stucky CL, Marchant JS. Use the force, fluke: Ligand-independent gating of Schistosoma mansoni ion channel TRPM PZQ. Int J Parasitol 2023:S0020-7519(22)00185-0. [PMID: 36610555 DOI: 10.1016/j.ijpara.2022.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/12/2022] [Accepted: 11/16/2022] [Indexed: 01/06/2023]
Abstract
The parasitic flatworm ion channel, TRPMPZQ, is a non-selective cation channel that mediates Ca2+ entry and membrane depolarization when activated by the anthelmintic drug, praziquantel (PZQ). TRPMPZQ is conserved in all platyhelminth genomes scrutinized to date, with the sensitivity of TRPMPZQ in any particular flatworm correlating with the overall sensitivity of the worm to PZQ. Conservation of this channel suggests it plays a role in flatworm physiology, but the nature of the endogenous cues that activate this channel are currently unknown. Here, we demonstrate that TRPMPZQ is activated in a ligand-independent manner by membrane stretch, with the electrophysiological signature of channel opening events being identical whether evoked by negative pressure, or by PZQ. TRPMPZQ is therefore a multimodal ion channel gated by both physical and chemical cues. The mechanosensitivity of TRPMPZQ is one route for endogenous activation of this ion channel that holds relevance for schistosome physiology given the persistent pressures and mechanical cues experienced throughout the parasite life cycle.
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Affiliation(s)
- Evgeny G Chulkov
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Elena Isaeva
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Cheryl L Stucky
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA.
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Park SK, Friedrich L, Yahya NA, Rohr CM, Chulkov EG, Maillard D, Rippmann F, Spangenberg T, Marchant JS. Mechanism of praziquantel action at a parasitic flatworm ion channel. Sci Transl Med 2021; 13:eabj5832. [PMID: 34936384 DOI: 10.1126/scitranslmed.abj5832] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Sang-Kyu Park
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Lukas Friedrich
- Computational Chemistry and Biology, Global Research & Development, Discovery Technologies, Merck Healthcare, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Nawal A Yahya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA.,Department of Pharmacology, University of Minnesota Medical School, 312 Church Street, Minneapolis, MN 55455, USA
| | - Claudia M Rohr
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Evgeny G Chulkov
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - David Maillard
- Central Process Development - Downstream Processing Services, Merck Performance Materials, Frankfurter Street 250, 64293 Darmstadt, Germany
| | - Friedrich Rippmann
- Computational Chemistry and Biology, Global Research & Development, Discovery Technologies, Merck Healthcare, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading S.A., a subsidiary of Merck KGaA, Darmstadt, Germany, 1262 Eysins, Switzerland
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee WI 53226, USA
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Chulkov EG, Smith E, Rohr CM, Yahya NA, Park SK, Scampavia L, Spicer TP, Marchant JS. Identification of novel modulators of a schistosome transient receptor potential channel targeted by praziquantel. PLoS Negl Trop Dis 2021; 15:e0009898. [PMID: 34731172 PMCID: PMC8565742 DOI: 10.1371/journal.pntd.0009898] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/11/2021] [Indexed: 12/24/2022] Open
Abstract
Given the worldwide burden of neglected tropical diseases, there is ongoing need to develop novel anthelmintic agents to strengthen the pipeline of drugs to combat these burdensome infections. Many diseases caused by parasitic flatworms are treated using the anthelmintic drug praziquantel (PZQ), employed for decades as the key clinical agent to treat schistosomiasis. PZQ activates a flatworm transient receptor potential (TRP) channel within the melastatin family (TRPMPZQ) to mediate sustained Ca2+ influx and worm paralysis. As a druggable target present in many parasitic flatworms, TRPMPZQ is a promising target for a target-based screening campaign with the goal of discovering novel regulators of this channel complex. Here, we have optimized methods to miniaturize a Ca2+-based reporter assay for Schistosoma mansoni TRPMPZQ (Sm.TRPMPZQ) activity enabling a high throughput screening (HTS) approach. This methodology will enable further HTS efforts against Sm.TRPMPZQ as well as other flatworm ion channels. A pilot screen of ~16,000 compounds yielded a novel activator of Sm.TRPMPZQ, and numerous potential blockers. The new activator of Sm.TRPMPZQ represented a distinct chemotype to PZQ, but is a known chemical entity previously identified by phenotypic screening. The fact that a compound prioritized from a phenotypic screening campaign is revealed to act, like PZQ, as an Sm.TRPMPZQ agonist underscores the validity of TRPMPZQ as a druggable target for antischistosomal ligands.
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Affiliation(s)
- Evgeny G. Chulkov
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Emery Smith
- Department of Molecular Medicine, Scripps Research, Jupiter, Florida, United States of America
| | - Claudia M. Rohr
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Nawal A. Yahya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Sang-Kyu Park
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Louis Scampavia
- Department of Molecular Medicine, Scripps Research, Jupiter, Florida, United States of America
| | - Timothy P. Spicer
- Department of Molecular Medicine, Scripps Research, Jupiter, Florida, United States of America
| | - Jonathan S. Marchant
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
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Klemens CA, Chulkov EG, Wu J, Hye Khan MA, Levchenko V, Flister MJ, Imig JD, Kriegel AJ, Palygin O, Staruschenko A. Loss of Chloride Channel 6 (CLC-6) Affects Vascular Smooth Muscle Contractility and Arterial Stiffness via Alterations to Golgi Calcium Stores. Hypertension 2021; 77:582-593. [PMID: 33390052 DOI: 10.1161/hypertensionaha.120.16589] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Genome-wide association studies have found a number of potential genes involved in blood pressure regulation; however, the functional role of many of these candidates has yet to be established. One such candidate gene is CLCN6, which encodes the transmembrane protein, chloride channel 6 (ClC-6). Although the CLCN6 locus has been widely associated with human blood pressure regulation, the mechanistic role of ClC-6 in blood pressure homeostasis at the molecular, cellular, and physiological levels is completely unknown. In this study, we demonstrate that rats with a functional knockout of ClC-6 on the Dahl Salt-Sensitive rat background (SS-Clcn6) have lower diastolic but not systolic blood pressures. The effect of diastolic blood pressure attenuation was independent of dietary salt exposure in knockout animals. Moreover, SS-Clcn6 rats are protected from hypertension-induced cardiac hypertrophy and arterial stiffening; however, they have impaired vasodilation and dysregulated intracellular calcium handling. ClC-6 is highly expressed in vascular smooth muscle cells where it is targeted to the Golgi apparatus. Using bilayer electrophysiology, we provide evidence that recombinant human ClC-6 protein can function as a channel. Last, we demonstrate that loss of ClC-6 function reduces Golgi calcium stores, which may play a previously unidentified role in vascular contraction and relaxation signaling in vascular smooth muscle cells. Collectively, these data indicate that ClC-6 may modulate blood pressure by regulating Golgi calcium reserves, which in turn contribute to vascular smooth muscle function.
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Affiliation(s)
- Christine A Klemens
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Evgeny G Chulkov
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Department of Cell Biology, Neurobiology and Anatomy (E.G.C.), Medical College of Wisconsin
| | - Jing Wu
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Md Abdul Hye Khan
- Department of Pharmacology (M.A.H.K., J.D.I.), Medical College of Wisconsin
| | - Vladislav Levchenko
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - Michael J Flister
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - John D Imig
- Department of Pharmacology (M.A.H.K., J.D.I.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Alison J Kriegel
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - Oleg Palygin
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Alexander Staruschenko
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin.,Clement J. Zablocki VA Medical Center, Milwaukee (A.S.)
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Park SK, Gunaratne GS, Chulkov EG, Moehring F, McCusker P, Dosa PI, Chan JD, Stucky CL, Marchant JS. The anthelmintic drug praziquantel activates a schistosome transient receptor potential channel. J Biol Chem 2019; 294:18873-18880. [PMID: 31653697 PMCID: PMC6901322 DOI: 10.1074/jbc.ac119.011093] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/24/2019] [Indexed: 11/06/2022] Open
Abstract
The anthelmintic drug praziquantel (PZQ) is used to treat schistosomiasis, a neglected tropical disease that affects over 200 million people worldwide. PZQ causes Ca2+ influx and spastic paralysis of adult worms and rapid vacuolization of the worm surface. However, the mechanism of action of PZQ remains unknown even after 40 years of clinical use. Here, we demonstrate that PZQ activates a schistosome transient receptor potential (TRP) channel, christened SmTRPMPZQ, present in parasitic schistosomes and other PZQ-sensitive parasites. Several properties of SmTRPMPZQ were consistent with known effects of PZQ on schistosomes, including (i) nanomolar sensitivity to PZQ; (ii) stereoselectivity toward (R)-PZQ; (iii) mediation of sustained Ca2+ signals in response to PZQ; and (iv) a pharmacological profile that mirrors the well-known effects of PZQ on muscle contraction and tegumental disruption. We anticipate that these findings will spur development of novel therapeutic interventions to manage schistosome infections and broader interest in PZQ, which is finally unmasked as a potent flatworm TRP channel activator.
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Affiliation(s)
- Sang-Kyu Park
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Gihan S Gunaratne
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Evgeny G Chulkov
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Francie Moehring
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Paul McCusker
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Peter I Dosa
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414
| | - John D Chan
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Cheryl L Stucky
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226.
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Efimova SS, Chulkov EG, Ostroumova OS. Lipid-mediated mode of action of local anesthetics on lipid pores induced by polyenes, peptides and lipopeptides. Colloids Surf B Biointerfaces 2018. [PMID: 29525621 DOI: 10.1016/j.colsurfb.2018.02.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effects of local anesthetics (LAs), namely, lidocaine (LDC), prilocaine (PLC), mepivacaine (MPV), bupivacaine (BPV), procaine (PC), and tetracaine (TTC), on the steady-state transmembrane conductance induced by the cis-side addition of the antifungal polyene macrolide antibiotic, nystatin (NYS), in planar lipid bilayers were studied. The addition of TTC to model membranes comprising DOPC and cholesterol (33 mol%) led to a nearly twenty-fold increase in the steady-state NYS-induced membrane conductance. BPV slightly enhanced the channel-forming activity of polyene. LDC, PLC, MPV, and PC did not affect the NYS-induced transmembrane current. We concluded that the effects of LAs on the channel-forming activity of NYS were in agreement with their effects on the elastic properties of model membranes. The ability of aminoamide LAs to promote calcein leakage from large unilamellar DOPC-vesicles was decreased in the following order: BPV >> LDC ≈ PLC ≈ MPV. LDC, PLC, and MPV produced a graded leakage of fluorescent marker from liposomes, up to 10-13%. A initial sharp jump in fluorescence after the introduction of BPV was attributed to the solubilization of liposomes and the formation of mixed DOPC:BPV-micelles. Differential scanning microcalorimetry (DSC) of large unilamellar DPPC-vesicles showed that the main transition temperature (Tm) is continuously decreased upon increasing concentrations of TTC. A sharp drop in the enthalpy of the transition at higher TTC concentrations indicated a formation of anesthetic/lipid mixed micelles. In contrast to TTC, PC slightly decreased Tm, broadened the DSC signal and did not provoke vesicle-to-micelle transition. Both the calcein leakage and DSC data together with the results of measurements of threshold voltages that are required to cause the lipid bilayer breakdown might indicate an alteration in the curvature lipid packing stress, induced by BPV and TTC. The data presented here lend support to a lipid-mediated mode of LAs action on NYS pores via an alteration in curvature stress near the trans-mouth. Similar results were obtained for several lipid pores, formed by polyene amphotericin B, lipopeptide syringomycin E, and the peptides magainin and melittin. This finding further developed the concept of non-specific regulation of lipid pores by LAs. In conclusion, the combination of nystatin with LAs could be a novel treatment for efficient therapy of superficial and mucosal candidiasis.
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Affiliation(s)
- Svetlana S Efimova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg 194064, Russia.
| | - Evgeny G Chulkov
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Olga S Ostroumova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg 194064, Russia
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Chulkov EG, Ostroumova OS. Phloretin modulates the rate of channel formation by polyenes. Biochimica et Biophysica Acta (BBA) - Biomembranes 2016; 1858:289-94. [DOI: 10.1016/j.bbamem.2015.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 11/05/2015] [Accepted: 12/01/2015] [Indexed: 12/12/2022]
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Chulkov EG, Efimova SS, Schagina LV, Ostroumova OS. Direct visualization of solid ordered domains induced by polyene antibiotics in giant unilamellar vesicles. Chem Phys Lipids 2014; 183:204-7. [DOI: 10.1016/j.chemphyslip.2014.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Revised: 07/18/2014] [Accepted: 07/22/2014] [Indexed: 10/25/2022]
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Chulkov EG, Schagina LV, Ostroumova OS. Membrane dipole modifiers modulate single-length nystatin channels via reducing elastic stress in the vicinity of the lipid mouth of a pore. Biochim Biophys Acta 2014; 1848:192-9. [PMID: 25223717 DOI: 10.1016/j.bbamem.2014.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 08/13/2014] [Accepted: 09/08/2014] [Indexed: 10/24/2022]
Abstract
The polyene antifungal antibiotic nystatin confers its biological activity by forming pores in the membranes of target cells. Exposure of only one side of the membrane to nystatin is more relevant than two-side exposure because in vivo antibiotic molecules initially interact with cell membrane from the exterior side. The effect of flavonoids and styryl dyes on the steady-state conductance induced by a cis-side addition of nystatin was investigated by using electrophysiological measurements on artificial membranes. The assessment of changes in membrane dipole potential by dipole modifiers was carried out by their influence on K(+)-nonactin (K(+)-valinomycin) current. The alterations of the phase segregation scenario induced by nystatin and flavonoids were observed via confocal fluorescence microscopy. The introduction of phloretin, phlorizin, biochanin A, myricetin, quercetin, taxifolin, genistin, genistein, and RH 421 leads to a significant increase in the nystatin-induced steady-state transmembrane current through membranes composed of a mixture of DOPC, cholesterol and sphingomyelin (57:33:10 mol%). Conversely, daidzein, catechin, trihydroxyacetophenone, and RH 237 do not affect the transmembrane current. Three possible mechanisms that explain the observed results are discussed: changes in the membrane dipole potential, alterations of the phase separation within the lipid bilayer, and influences of the dipole modifiers on the formation of the lipid mouth of the polyene pore. Most likely, changes in the monolayer curvature in the vicinity of trans-mouth of a nystatin single-length channel prevail over alterations of dipole potential of membrane and the phase segregation scenarios induced by dipole modifiers.
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Affiliation(s)
- Evgeny G Chulkov
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky Ave. 4, St. Petersburg 194064, Russia.
| | - Ludmila V Schagina
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky Ave. 4, St. Petersburg 194064, Russia
| | - Olga S Ostroumova
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky Ave. 4, St. Petersburg 194064, Russia
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Ostroumova OS, Chulkov EG, Stepanenko OV, Schagina LV. Effect of flavonoids on the phase separation in giant unilamellar vesicles formed from binary lipid mixtures. Chem Phys Lipids 2013; 178:77-83. [PMID: 24361549 DOI: 10.1016/j.chemphyslip.2013.12.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 11/03/2013] [Accepted: 12/09/2013] [Indexed: 11/30/2022]
Abstract
Confocal fluorescence microscopy have been employed to investigate phase separation in giant unilamellar vesicles prepared from binary mixtures of unsaturated dioleoylphosphocholine with saturated phosphocholines or brain sphingomyelin in the absence and presence of the flavonoids, biochanin A, phloretin, and myricetin. It has been demonstrated that biochanin A and phloretin make uncolored domains more circular or eliminate visible phase separation in liposomes while myricetin remains the irregular shape of fluorescence probe-excluding domains. Influence of the flavonoids on the endotherms of liposome suspension composed of dioleoylphosphocholine and dimyristoylphosphocholine was investigated by the differential scanning calorimetry. Calorimetry data do not contradict to confocal imaging results.
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Affiliation(s)
- Olga S Ostroumova
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky ave. 4, St. Petersburg 194064, Russia.
| | - Evgeny G Chulkov
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky ave. 4, St. Petersburg 194064, Russia
| | - Olga V Stepanenko
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky ave. 4, St. Petersburg 194064, Russia
| | - Ludmila V Schagina
- Institute of Cytology of the Russian Academy of Sciences, Tikhoretsky ave. 4, St. Petersburg 194064, Russia
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Abstract
Recently, we showed that the effect of dipole modifiers (flavonoids and styrylpyridinium dyes) on the conductance of single amphotericin B (AmB) channels in sterol-containing lipid bilayers primarily resulted from changes in the membrane dipole potential. The present study examines the effect of dipole modifiers on the AmB multi-channel activity. The addition of phloretin to cholesterol-containing membranes leads to a significant increase in the steady-state AmB-induced transmembrane current. Quercetin significantly decreases and RH 421 increases the current through ergosterol-containing bilayers. Other tested flavonoids and styrylpyridinium dyes do not affect the channel-forming activity of AmB independently on the sterol composition of the bilayers. The effects obtained in these trials may instead be attributed to the direct interaction of dipole modifiers with AmB/sterol complexes and not to the effect of dipole potential changes. The presence of double bonds in the Δ7 and Δ22 positions of sterol molecules, the number of conjugated double bonds and amino sugar residues in polyene molecules, and the conformation and adsorption plane of dipole modifiers are important factors impacting this interaction.
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Affiliation(s)
- Olga S Ostroumova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, Russia.
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Chulkov EG, Shatunova GA, Onufrienok IP. [Methods of production of standard liquid mud preparations]. Vopr Kurortol Fizioter Lech Fiz Kult 1965; 30:548-50. [PMID: 5874464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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