1
|
Alkassar M, Tudó À, Rambla-Alegre M, Ferreres L, Diogène J, Sureda FX, Campàs M. First record of paralytic shellfish toxins in marine pufferfish from the Spanish Mediterranean coast using cell-based assay, automated patch clamp and HPLC-FLD. CHEMOSPHERE 2024; 364:143053. [PMID: 39121960 DOI: 10.1016/j.chemosphere.2024.143053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 08/06/2024] [Accepted: 08/06/2024] [Indexed: 08/12/2024]
Abstract
Pufferfish is one of the most poisonous marine organisms, responsible for numerous poisoning incidents and some human fatalities due to its capability to accumulate potent neurotoxins such as tetrodotoxins (TTXs) and paralytic shellfish toxins (PSTs). In this study, tissue extracts (muscle, skin, liver, intestinal tract and gonads) obtained from sixteen pufferfish specimens of the Lagocephalus lagocephalus and Sphoeroides pachygaster species, collected along the Spanish Mediterranean coast, were analysed for the presence of voltage-gated sodium channel (also known as Nav channel) blockers using cell-based assay (CBA) and automated patch clamp (APC). No toxicity was observed in any of the S. pachygaster specimens, but toxicity was detected in the liver of most L. lagocephalus specimens. Instrumental analysis of these specimens, as well as in one Lagocephalus sceleratus specimen, by high-performance liquid chromatography coupled to fluorescence detection (HPLC-FLD) was performed, which confirmed the presence of PSTs only in L. lagocephalus specimens. This analysis reported the presence of saxitoxin (STX) and decarbamoylsaxitoxin (dcSTX) in all positive samples, being dcSTX the major analogue. These results demonstrate the ability of this species to accumulate PSTs, being the first report of the presence of PSTs in Mediterranean L.lagocephalus specimens. Furthermore, the presence of high PSTs contents in all five tested tissues of one L. lagocephalus specimen pointed the risk that the presence of this toxic fish in the Mediterranean Sea may represent for seafood safety and human health in case of accidental consumption.
Collapse
Affiliation(s)
- Mounira Alkassar
- IRTA, Ctra. Poble Nou Km 5.5, 43540, La Ràpita, Spain; Universitat Rovira I Virgili, Av. Països Catalans 26, 43007, Tarragona, Spain
| | - Àngels Tudó
- Universitat Rovira I Virgili, Av. Països Catalans 26, 43007, Tarragona, Spain
| | | | | | - Jorge Diogène
- IRTA, Ctra. Poble Nou Km 5.5, 43540, La Ràpita, Spain
| | - Francesc X Sureda
- Universitat Rovira I Virgili, Av. Països Catalans 26, 43007, Tarragona, Spain
| | - Mònica Campàs
- IRTA, Ctra. Poble Nou Km 5.5, 43540, La Ràpita, Spain.
| |
Collapse
|
2
|
Elleman AV, Milicic N, Williams DJ, Simko J, Liu CJ, Haynes AL, Ehrlich DE, Makinson CD, Du Bois J. Behavioral control through the direct, focal silencing of neuronal activity. Cell Chem Biol 2024; 31:1324-1335.e20. [PMID: 38729162 PMCID: PMC11260259 DOI: 10.1016/j.chembiol.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 01/02/2024] [Accepted: 04/09/2024] [Indexed: 05/12/2024]
Abstract
The ability to optically stimulate and inhibit neurons has revolutionized neuroscience research. Here, we present a direct, potent, user-friendly chemical approach for optically silencing neurons. We have rendered saxitoxin (STX), a naturally occurring paralytic agent, transiently inert through chemical protection with a previously undisclosed nitrobenzyl-derived photocleavable group. Exposing the caged toxin, STX-bpc, to a brief (5 ms) pulse of light effects rapid release of a potent STX derivative and transient, spatially precise blockade of voltage-gated sodium channels (NaVs). We demonstrate the efficacy of STX-bpc for parametrically manipulating action potentials in mammalian neurons and brain slice. Additionally, we show the effectiveness of this reagent for silencing neural activity by dissecting sensory-evoked swimming in larval zebrafish. Photo-uncaging of STX-bpc is a straightforward method for non-invasive, reversible, spatiotemporally precise neural silencing without the need for genetic access, thus removing barriers for comparative research.
Collapse
Affiliation(s)
- Anna V Elleman
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA
| | - Nikola Milicic
- Department of Integrative Biology, University of Wisconsin-Madison, 121 Integrative Biology Research Building, 1117 W Johnson St, Madison, WI 53706, USA
| | - Damian J Williams
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, 710 W 168th St, New York, NY 10032, USA
| | - Jane Simko
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, 710 W 168th St, New York, NY 10032, USA
| | - Christine J Liu
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, 710 W 168th St, New York, NY 10032, USA; Department of Neuroscience, Columbia University, Jerome L. Greene Science Center, 3227 Broadway, MC 9872, New York, NY 10027, USA
| | - Allison L Haynes
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA
| | - David E Ehrlich
- Department of Integrative Biology, University of Wisconsin-Madison, 121 Integrative Biology Research Building, 1117 W Johnson St, Madison, WI 53706, USA.
| | - Christopher D Makinson
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, 710 W 168th St, New York, NY 10032, USA; Department of Neuroscience, Columbia University, Jerome L. Greene Science Center, 3227 Broadway, MC 9872, New York, NY 10027, USA.
| | - J Du Bois
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA.
| |
Collapse
|
3
|
Campàs M, Reverté J, Tudó À, Alkassar M, Diogène J, Sureda FX. Automated Patch Clamp for the Detection of Tetrodotoxin in Pufferfish Samples. Mar Drugs 2024; 22:176. [PMID: 38667793 PMCID: PMC11050952 DOI: 10.3390/md22040176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/10/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Tetrodotoxin (TTX) is a marine toxin responsible for many intoxications around the world. Its presence in some pufferfish species and, as recently reported, in shellfish, poses a serious health concern. Although TTX is not routinely monitored, there is a need for fast, sensitive, reliable, and simple methods for its detection and quantification. In this work, we describe the use of an automated patch clamp (APC) system with Neuro-2a cells for the determination of TTX contents in pufferfish samples. The cells showed an IC50 of 6.4 nM for TTX and were not affected by the presence of muscle, skin, liver, and gonad tissues of a Sphoeroides pachygaster specimen (TTX-free) when analysed at 10 mg/mL. The LOD achieved with this technique was 0.05 mg TTX equiv./kg, which is far below the Japanese regulatory limit of 2 mg TTX equiv./kg. The APC system was applied to the analysis of extracts of a Lagocephalus sceleratus specimen, showing TTX contents that followed the trend of gonads > liver > skin > muscle. The APC system, providing an in vitro toxicological approach, offers the advantages of being sensitive, rapid, and reliable for the detection of TTX-like compounds in seafood.
Collapse
Affiliation(s)
- Mònica Campàs
- IRTA, Marine and Continental Waters (AMiC) Programme, Ctra. Poble Nou del Delta, km. 5.5, 43540 La Ràpita, Spain; (J.R.); (M.A.); (J.D.)
| | - Jaume Reverté
- IRTA, Marine and Continental Waters (AMiC) Programme, Ctra. Poble Nou del Delta, km. 5.5, 43540 La Ràpita, Spain; (J.R.); (M.A.); (J.D.)
- Department of Basic Medical Sciences, Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus, Spain;
| | - Àngels Tudó
- Department of Basic Medical Sciences, Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus, Spain;
| | - Mounira Alkassar
- IRTA, Marine and Continental Waters (AMiC) Programme, Ctra. Poble Nou del Delta, km. 5.5, 43540 La Ràpita, Spain; (J.R.); (M.A.); (J.D.)
- Department of Basic Medical Sciences, Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus, Spain;
| | - Jorge Diogène
- IRTA, Marine and Continental Waters (AMiC) Programme, Ctra. Poble Nou del Delta, km. 5.5, 43540 La Ràpita, Spain; (J.R.); (M.A.); (J.D.)
| | - Francesc X. Sureda
- Department of Basic Medical Sciences, Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus, Spain;
| |
Collapse
|
4
|
Chen J, Noorlander A, Wesseling S, Bouwmeester H, Kramer NI, Rietjens IMCM. Integrating In Vitro Data and Physiologically Based Kinetic Modeling to Predict and Compare Acute Neurotoxic Doses of Saxitoxin in Rats, Mice, and Humans. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37478462 PMCID: PMC10399293 DOI: 10.1021/acs.est.3c01987] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Current climate trends are likely to expand the geographic distribution of the toxigenic microalgae and concomitant phycotoxins, making intoxications by such toxins a global phenomenon. Among various phycotoxins, saxitoxin (STX) acts as a neurotoxin that might cause severe neurological symptoms in mammals following consumptions of contaminated seafood. To derive a point of departure (POD) for human health risk assessment upon acute neurotoxicity induced by oral STX exposure, a physiologically based kinetic (PBK) modeling-facilitated quantitative in vitro to in vivo extrapolation (QIVIVE) approach was employed. The PBK models for rats, mice, and humans were built using parameters from the literature, in vitro experiments, and in silico predictions. Available in vitro toxicity data for STX were converted to in vivo dose-response curves via the PBK models established for these three species, and POD values were derived from the predicted curves and compared to reported in vivo toxicity data. Interspecies differences in acute STX toxicity between rodents and humans were found, and they appeared to be mainly due to differences in toxicokinetics. The described approach resulted in adequate predictions for acute oral STX exposure, indicating that new approach methodologies, when appropriately integrated, can be used in a 3R-based chemical risk assessment paradigm.
Collapse
Affiliation(s)
- Jiaqi Chen
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| | - Annelies Noorlander
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| | - Sebastiaan Wesseling
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| | - Hans Bouwmeester
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| | - Nynke I Kramer
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University and Research, Stippeneng 4, Wageningen, Gelderland 6708 WE, The Netherlands
| |
Collapse
|
5
|
Hinzpeter J, Barahona M, Aliste J, Barrientos C, Zamorano A, Palet M, Catalan J, Campo MD, Lagos N. Gonyautoxins 2/3 Local Periarticular Injection for Pain Management after Total Knee Arthroplasty: A Double-Blind, Randomized Study. J Knee Surg 2023; 36:389-396. [PMID: 34507361 DOI: 10.1055/s-0041-1735312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to compare the efficacy of periarticular infiltration of gonyautoxin 2/3 (GTX 2/3) and a mixture of levobupivacaine, ketorolac, and epinephrine for pain management after total knee arthroplasty (TKA). Forty-eight patients were randomly allocated to receive periarticular infiltration of 40 µg GTX 2/3 (n = 24) diluted in 30 mL of sodium chloride 0.9% (study group) or a combination of 300 mg of levobupivacaine, 1 mg of epinephrine, and 60 mg ketorolac (n = 24) diluted in 150 mL of sodium chloride 0.9% (control group). Intraoperative anesthetic and surgical techniques were identical for both groups. Postoperatively, all patients received patient-controlled analgesia (morphine bolus of 1 mg; lockout interval of 8 minutes), acetaminophen, and ketoprofen for 72 hours. A blinded investigator recorded morphine consumption, which was the primary outcome. Also, the range of motion (ROM) and static and dynamic pain were assessed at 6, 12, 36, and 60 hours after surgery. The incidence of adverse events, time to readiness for discharge, and length of hospital stay were also recorded. The median of total cumulative morphine consumption was 16 mg (range, 0-62 mg) in the GTX 2/3 group and 9 mg (range, 0-54 mg) in control group, which did not reach statistical difference (median test, p = 0.40). Furthermore, static and dynamic pain scores were similar at all time intervals. GTX 2/3 was inferior in range of motion at 6 and 12 hours; nevertheless, we noted no difference after 36 hours. No differences between groups were found in terms of complications, side effects, or length of hospital stay. No significant differences were found between groups in terms of breakthrough morphine requirement. However, local anesthetic use resulted in an increased ROM in the first 12 hours. This prospective randomized clinical trial shows that GTX 2/3 is a safe and efficient drug for pain control after TKA; nevertheless, more studies using GTX 2/3 with larger populations are needed to confirm the safety profile and efficiency. This is level 1 therapeutic study, randomized, double-blind clinical trial.
Collapse
Affiliation(s)
- Jaime Hinzpeter
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Maximiliano Barahona
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Julián Aliste
- Department of Anesthesiology and Perioperative Medicine, Hospital Clínico Universidad de Chile, Santiago, Chile
| | - Cristian Barrientos
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile.,Department of Orthopedics, Clínica Santa María, Santiago, Chile
| | - Alvaro Zamorano
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Miguel Palet
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Jaime Catalan
- Department of Orthopedics, Hospital Clinico Universidad de Chile, Santiago, Chile
| | - Miguel Del Campo
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine Universidad de Chile, Santiago, Chile
| | - Néstor Lagos
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine Universidad de Chile, Santiago, Chile
| |
Collapse
|
6
|
Pajouhesh H, Delwig A, Beckley JT, Klas S, Monteleone D, Zhou X, Luu G, Du Bois J, Hunter JC, Mulcahy JV. Discovery of Selective Inhibitors of Na V1.7 Templated on Saxitoxin as Therapeutics for Pain. ACS Med Chem Lett 2022; 13:1763-1768. [PMID: 36385936 PMCID: PMC9661704 DOI: 10.1021/acsmedchemlett.2c00378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 10/05/2022] [Indexed: 11/28/2022] Open
Abstract
The voltage-gated sodium channel isoform NaV1.7 has drawn widespread interest as a target for non-opioid, investigational new drugs to treat pain. Selectivity over homologous, off-target sodium channel isoforms, which are expressed in peripheral motor neurons, the central nervous system, skeletal muscle and the heart, poses a significant challenge to the development of small molecule inhibitors of NaV1.7. Most inhibitors of NaV1.7 disclosed to date belong to a class of aryl and acyl sulfonamides that preferentially bind to an inactivated conformation of the channel. By taking advantage of a sequence variation unique to primate NaV1.7 in the extracellular pore of the channel, a series of bis-guanidinium analogues of the natural product, saxitoxin, has been identified that are potent against the resting conformation of the channel. A compound of interest, 25, exhibits >600-fold selectivity over off-target sodium channel isoforms and is efficacious in a preclinical model of acute pain.
Collapse
Affiliation(s)
- Hassan Pajouhesh
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - Anton Delwig
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - Jacob T. Beckley
- SiteOne
Therapeutics, Inc., Bozeman, Montana 59715, United States
| | - Sheri Klas
- SiteOne
Therapeutics, Inc., Bozeman, Montana 59715, United States
| | - Dennis Monteleone
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - Xiang Zhou
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - George Luu
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - J. Du Bois
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - John C. Hunter
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| | - John V. Mulcahy
- SiteOne
Therapeutics, Inc., South San Francisco, California 94080, United States
| |
Collapse
|
7
|
Louzao MC, Vilariño N, Vale C, Costas C, Cao A, Raposo-Garcia S, Vieytes MR, Botana LM. Current Trends and New Challenges in Marine Phycotoxins. Mar Drugs 2022; 20:md20030198. [PMID: 35323497 PMCID: PMC8950113 DOI: 10.3390/md20030198] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/04/2022] [Accepted: 03/05/2022] [Indexed: 02/04/2023] Open
Abstract
Marine phycotoxins are a multiplicity of bioactive compounds which are produced by microalgae and bioaccumulate in the marine food web. Phycotoxins affect the ecosystem, pose a threat to human health, and have important economic effects on aquaculture and tourism worldwide. However, human health and food safety have been the primary concerns when considering the impacts of phycotoxins. Phycotoxins toxicity information, often used to set regulatory limits for these toxins in shellfish, lacks traceability of toxicity values highlighting the need for predefined toxicological criteria. Toxicity data together with adequate detection methods for monitoring procedures are crucial to protect human health. However, despite technological advances, there are still methodological uncertainties and high demand for universal phycotoxin detectors. This review focuses on these topics, including uncertainties of climate change, providing an overview of the current information as well as future perspectives.
Collapse
Affiliation(s)
- Maria Carmen Louzao
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
- Correspondence: (M.C.L.); (L.M.B.)
| | - Natalia Vilariño
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
| | - Carmen Vale
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
| | - Celia Costas
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
| | - Alejandro Cao
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
| | - Sandra Raposo-Garcia
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
| | - Mercedes R. Vieytes
- Departamento de Fisiologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain;
| | - Luis M. Botana
- Departamento de Farmacologia, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (N.V.); (C.V.); (C.C.); (A.C.); (S.R.-G.)
- Correspondence: (M.C.L.); (L.M.B.)
| |
Collapse
|
8
|
Boundy MJ, Harwood DT, Tommasi E, Burger E, van Ginkel R, Waugh C, Selwood AI, Finch S. Acute toxicity of decarbamoyl gonyautoxin 1&4 to mice by various routes of administration. Toxicon 2021; 204:56-63. [PMID: 34742781 DOI: 10.1016/j.toxicon.2021.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/08/2021] [Accepted: 11/02/2021] [Indexed: 11/16/2022]
Abstract
Saxitoxin and its derivatives, the paralytic shellfish toxins (PSTs), are well known to be toxic to humans, and maximum permitted levels in seafood have been established by regulatory authorities in many countries. Monitoring of PSTs is typically performed using chemical methods which quantify the concentration of the individual PST analogues, of which there are many. However, since the toxicities of analogues are different, they do not equally contribute to the overall toxicity of the sample. To account for these differences, toxicity equivalency factors (TEFs) need to be determined for each analogue and applied. Currently there are no established TEFs for decarbamoyl gonyautoxin 1&4 (dcGTX1&4), which occurs in some clam species such as Mactra chinensis contaminated with PSTs due to metabolism within the shellfish. In this study the median lethal dose of purified, equilibrated epimeric mixture of dcGTX1&4 has been determined by intraperitoneal injection (i.p.) (4.75 μmol/kg) and by feeding (34.9 μmol/kg). The most relevant route of exposure is orally with feeding being more representative of human consumption and more reliable than gavage. Based on the median lethal dose by feeding, a TEF of 0.1 is recommended for dcGTX1&4. Receptor binding activity and i.p. toxicity results showed dcGTX1&4 to be much less toxic than STX (140-170-fold). However, by feeding a much smaller difference in toxicity was observed with dcGTX1&4 being only 11-fold less toxic than STX. Analysis of the gut contents of mice dosed with dcGTX1&4 showed the presence of decarbamoyl gonyautoxin 2&3, decarbamoyl saxitoxin and decarbamoyl neosaxitoxin, all of which are of greater toxicity. This conversion of dcGTX1&4 within the digestive track to more toxic congeners may explain the high relative toxicity of dcGTX1&4 by feeding compared to that determined by i.p. and by sodium channel activity.
Collapse
Affiliation(s)
| | - D Tim Harwood
- Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
| | - Elena Tommasi
- Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
| | - Emillie Burger
- Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
| | - Roel van Ginkel
- Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
| | - Craig Waugh
- Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
| | | | - Sarah Finch
- AgResearch Limited, Ruakura Research Centre, Private Bag 3123, Hamilton, 3240, New Zealand
| |
Collapse
|
9
|
Montero C, Riquelme G, Del Campo M, Lagos N. Neosaxitoxin, a Paralytic Shellfish Poison phycotoxin, blocks pain and inflammation in equine osteoarthritis. Toxicon 2021; 204:5-8. [PMID: 34666135 DOI: 10.1016/j.toxicon.2021.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/04/2021] [Accepted: 10/12/2021] [Indexed: 11/28/2022]
Abstract
The Osteoarthritis is a chronic disease characterized by a progressive deterioration of the articular cartilage producing a strong inflammatory activity and chronic pain in patients. Horses also show osteoarthritis. Since the activation and progression of the disease are similar to that of human we developed a study model in horses. In this study, we test the effect of Neosaxitoxin, a phycotoxin from Paralytic Shellfish Poison, in the remediation of osteoarthritis equine clinical symptoms such as pain (showed in lameness) and inflammation quantifying the amounts of pro-inflammatory markers like cellular infiltration, TNF-alpha and nitric oxide in the synovial fluid obtained from the horse damaged joint. The outcomes show that Neosaxitoxin blocks pain for long lasting period (average 24.7 days). Furthermore, the amounts of pro-inflammatory markers were reduced and consequently an enhanced horse's well-being was obtained. Neosaxitoxin showed to be a candidate for establishing treatment protocols for OA, being safe and effective as a pain blocker in equine osteoarthritis.
Collapse
Affiliation(s)
- Cecilia Montero
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, 8380000, Santiago, Chile
| | - Gricel Riquelme
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, 8380000, Santiago, Chile
| | - Miguel Del Campo
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, 8380000, Santiago, Chile
| | - Néstor Lagos
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, 8380000, Santiago, Chile.
| |
Collapse
|
10
|
Leal JF, Cristiano MLS. Marine paralytic shellfish toxins: chemical properties, mode of action, newer analogues, and structure-toxicity relationship. Nat Prod Rep 2021; 39:33-57. [PMID: 34190283 DOI: 10.1039/d1np00009h] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Up to the end of 2020Every year, the appearance of marine biotoxins causes enormous socio-economic damage worldwide. Among the major groups of biotoxins, paralytic shellfish toxins, comprising saxitoxin and its analogues (STXs), are the ones that cause the most severe effects on humans, including death. However, the knowledge that currently exists on their chemistry, properties and mode of toxicological action is disperse and partially outdated. This review intends to systematically compile the dispersed information, updating and complementing it. With this purpose, it addresses several aspects related to the molecular structure of these toxins. Special focus is given to the bioconversion reactions that may occur in the different organisms (dinoflagellates, bivalves, and humans) and the possible mediators involved. A critical review of the most recently discovered analogues, the M-series toxins, is presented. Finally, a deep discussion about the relationship between the molecular structure (e.g., effect of the substituting groups and the net charge of the molecules) and the toxic activity of these molecules is performed, proposing the concept of "toxicological traffic light" based on the toxicity equivalency factors (TEFs).
Collapse
Affiliation(s)
- Joana F Leal
- Centre of Marine Sciences (CCMAR), Department of Chemistry and Pharmacy, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
| | - Maria L S Cristiano
- Centre of Marine Sciences (CCMAR), Department of Chemistry and Pharmacy, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
| |
Collapse
|
11
|
Dillon M, Zaczek-Moczydlowska MA, Edwards C, Turner AD, Miller PI, Moore H, McKinney A, Lawton L, Campbell K. Current Trends and Challenges for Rapid SMART Diagnostics at Point-of-Site Testing for Marine Toxins. SENSORS (BASEL, SWITZERLAND) 2021; 21:2499. [PMID: 33916687 PMCID: PMC8038394 DOI: 10.3390/s21072499] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/21/2021] [Accepted: 03/24/2021] [Indexed: 12/26/2022]
Abstract
In the past twenty years marine biotoxin analysis in routine regulatory monitoring has advanced significantly in Europe (EU) and other regions from the use of the mouse bioassay (MBA) towards the high-end analytical techniques such as high-performance liquid chromatography (HPLC) with tandem mass spectrometry (MS). Previously, acceptance of these advanced methods, in progressing away from the MBA, was hindered by a lack of commercial certified analytical standards for method development and validation. This has now been addressed whereby the availability of a wide range of analytical standards from several companies in the EU, North America and Asia has enhanced the development and validation of methods to the required regulatory standards. However, the cost of the high-end analytical equipment, lengthy procedures and the need for qualified personnel to perform analysis can still be a challenge for routine monitoring laboratories. In developing regions, aquaculture production is increasing and alternative inexpensive Sensitive, Measurable, Accurate and Real-Time (SMART) rapid point-of-site testing (POST) methods suitable for novice end users that can be validated and internationally accepted remain an objective for both regulators and the industry. The range of commercial testing kits on the market for marine toxin analysis remains limited and even more so those meeting the requirements for use in regulatory control. Individual assays include enzyme-linked immunosorbent assays (ELISA) and lateral flow membrane-based immunoassays (LFIA) for EU-regulated toxins, such as okadaic acid (OA) and dinophysistoxins (DTXs), saxitoxin (STX) and its analogues and domoic acid (DA) in the form of three separate tests offering varying costs and benefits for the industry. It can be observed from the literature that not only are developments and improvements ongoing for these assays, but there are also novel assays being developed using upcoming state-of-the-art biosensor technology. This review focuses on both currently available methods and recent advances in innovative methods for marine biotoxin testing and the end-user practicalities that need to be observed. Furthermore, it highlights trends that are influencing assay developments such as multiplexing capabilities and rapid POST, indicating potential detection methods that will shape the future market.
Collapse
Affiliation(s)
- Michael Dillon
- Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (M.D.); (M.A.Z.-M.)
- Faculty of Health, Peninsula Medical School, University of Plymouth, Plymouth PL4 8AA, UK
| | - Maja A. Zaczek-Moczydlowska
- Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (M.D.); (M.A.Z.-M.)
| | - Christine Edwards
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK; (C.E.); (L.L.)
| | - Andrew D. Turner
- Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK;
| | - Peter I. Miller
- Plymouth Marine Laboratory, Remote Sensing Group, Prospect Place, Plymouth PL1 3DH, UK;
| | - Heather Moore
- Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, Northern Ireland BT9 5PX, UK; (H.M.); (A.M.)
| | - April McKinney
- Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, Northern Ireland BT9 5PX, UK; (H.M.); (A.M.)
| | - Linda Lawton
- School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK; (C.E.); (L.L.)
| | - Katrina Campbell
- Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (M.D.); (M.A.Z.-M.)
| |
Collapse
|
12
|
Gao J, Liao C, Liu S, Xia T, Jiang G. Nanotechnology: new opportunities for the development of patch-clamps. J Nanobiotechnology 2021; 19:97. [PMID: 33794903 PMCID: PMC8017657 DOI: 10.1186/s12951-021-00841-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/23/2021] [Indexed: 12/29/2022] Open
Abstract
The patch-clamp technique is one of the best approaches to investigate neural excitability. Impressive improvements towards the automation of the patch-clamp technique have been made, but obvious limitations and hurdles still exist, such as parallelization, volume displacement in vivo, and long-term recording. Nanotechnologies have provided opportunities to overcome these hurdles by applying electrical devices on the nanoscale. Electrodes based on nanowires, nanotubes, and nanoscale field-effect transistors (FETs) are confirmed to be robust and less invasive tools for intracellular electrophysiological recording. Research on the interface between the nanoelectrode and cell membrane aims to reduce the seal conductance and further improve the recording quality. Many novel recording approaches advance the parallelization, and precision with reduced invasiveness, thus improving the overall intracellular recording system. The combination of nanotechnology and the present intracellular recording framework is a revolutionary and promising orientation, potentially becoming the next generation electrophysiological recording technique and replacing the conventional patch-clamp technique. Here, this paper reviews the recent advances in intracellular electrophysiological recording techniques using nanotechnology, focusing on the design of noninvasive and greatly parallelized recording systems based on nanoelectronics.
Collapse
Affiliation(s)
- Jia Gao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chunyang Liao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China. .,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Sijin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tian Xia
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| |
Collapse
|
13
|
Cho Y, Hidema S, Omura T, Koike K, Koike K, Oikawa H, Konoki K, Oshima Y, Yotsu-Yamashita M. SxtA localizes to chloroplasts and changes to its 3'UTR may reduce toxin biosynthesis in non-toxic Alexandrium catenella (Group I) ✰. HARMFUL ALGAE 2021; 101:101972. [PMID: 33526188 DOI: 10.1016/j.hal.2020.101972] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/14/2020] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
SxtA is the enzyme that catalyses the first step of saxitoxin biosynthesis. We developed an immunofluorescent method to detect SxtA using antibodies against SxtA peptides. Confocal microscopy revealed the presence of abundant, sub-cellularly localized signal in cells of toxic species and its absence in non-toxic species. Co-localization of SxtA with Rubisco II and ultra-structural observation by transmission electron microscopy strongly suggested the association of SxtA with chloroplasts. We also characterized a non-toxic sub-clone of Alexandrium catenella (Group I) to elucidate the mutation responsible for its loss of toxicity. Although sxtA4 gene copy number was indistinguishable in toxic and non-toxic sub-clones, mRNA and protein expression were significantly reduced in the non-toxic sub-clone and we uncovered sequence variation at the 3' untranslated region (3'UTR) of sxtA4 mRNA. We propose that differences in the sxtA4 mRNA 3'UTR lead to down-regulation of STX biosynthesis post-transcriptionally, thereby explaining the differences in toxicity amongst different A. catenella (Group I) sub-clones.
Collapse
Affiliation(s)
- Yuko Cho
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan.
| | - Shizu Hidema
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University, 1 Hikariga-oka, Fukushima 960-1295, Japan
| | - Takuo Omura
- Laboratory of Aquatic Science Consultant Co., Ltd. 2-30-17, Higashikamata, Ota-ku, Tokyo 144-0031, Japan
| | - Kazuhiko Koike
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8528, Japan
| | - Kanae Koike
- Natural Science Center for Basic Research and Development, Hiroshima University, 1-4-4 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8528, Japan
| | - Hiroshi Oikawa
- Japan Fisheries Research and Education Agency, Fisheries Technology Institute, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan
| | - Keiichi Konoki
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Yasukatsu Oshima
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Mari Yotsu-Yamashita
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| |
Collapse
|
14
|
Gao J, Zhang H, Xiong P, Yan X, Liao C, Jiang G. Application of electrophysiological technique in toxicological study: From manual to automated patch-clamp recording. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.116082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
15
|
Collaço RDC, Hyslop S, Rocha T, Dorce VAC, Rowan EG, Antunes E. Neurotoxicity of Tityus bahiensis (brown scorpion) venom in sympathetic vas deferens preparations and neuronal cells. Arch Toxicol 2020; 94:3315-3327. [PMID: 32548756 PMCID: PMC7415753 DOI: 10.1007/s00204-020-02799-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/28/2020] [Indexed: 01/04/2023]
Abstract
Systemic scorpion envenomation is characterized by massive neurotransmitter release from peripheral nerves mediated primarily by scorpion venoms neurotoxins. Tityus bahiensis is one of the medically most important species in Brazil, but its venom pharmacology, especially regarding to peripheral nervous system, is poorly understood. Here, we evaluated the T. bahiensis venom activity on autonomic (sympathetic) neurotransmission by using a variety of approaches, including vas deferens twitch-tension recordings, electrophysiological measurements (resting membrane potentials, spontaneous excitatory junctional potentials and whole-cell patch-clamp), calcium imaging and histomorphological analysis. Low concentrations of venom (≤ 3 μg/mL) facilitated the electrically stimulated vas deferens contractions without affecting postsynaptic receptors or damaging the smooth muscle cells. Transient TTX-sensitive sustained contractions and resting membrane depolarization were mediated mainly by massive spontaneous ATP release. High venom concentrations (≥ 10 μg/mL) blocked the muscle contractions and induced membrane depolarization. In neuronal cells (ND7-23wt), the venom increased the peak sodium current, modified the current-voltage relationship by left-shifting the Nav-channel activation curve, thereby facilitating the opening of these channels. The venom also caused a time-dependent increase in neuronal calcium influx. These results indicate that the sympathetic hyperstimulation observed in systemic envenomation is presynaptically driven, probably through the interaction of α- and β-toxins with neuronal sodium channels.
Collapse
Affiliation(s)
- Rita de Cássia Collaço
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil.
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK.
| | - Stephen Hyslop
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Thalita Rocha
- São Francisco University (USF), Bragança Paulista, SP, Brazil
| | - Valquiria A C Dorce
- Laboratory of Pharmacology, Division for Scientific Development, Butantan Institute, São Paulo, SP, Brazil
| | - Edward G Rowan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil
| |
Collapse
|
16
|
Adachi K, Yamada T, Ishizuka H, Oki M, Tsunogae S, Shimada N, Chiba O, Orihara T, Hidaka M, Hirokawa T, Odagi M, Konoki K, Yotsu‐Yamashita M, Nagasawa K. Synthesis of C12‐Keto Saxitoxin Derivatives with Unusual Inhibitory Activity Against Voltage‐Gated Sodium Channels. Chemistry 2020; 26:2025-2033. [DOI: 10.1002/chem.201904184] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 11/04/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Kanna Adachi
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| | - Tomoshi Yamada
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Hayate Ishizuka
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| | - Mana Oki
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| | - Shunsuke Tsunogae
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Noriko Shimada
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Osamu Chiba
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Tatsuya Orihara
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| | - Masafumi Hidaka
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Takatsugu Hirokawa
- Transborder Medical Research Center University of Tsukuba 1-1-1 Tennodai Tsukuba 305-8575 Japan
- Division of Biomedical Science University of Tsukuba 1-1-1 Tennodai Tsukuba 305-8575 Japan
- Molecular Profiling Research Center for Drug Discovery National Institute of Advanced Industrial Science and Technology 2-4-7 Aomi, Koto-ward Tokyo 135-0064 Japan
| | - Minami Odagi
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| | - Keiichi Konoki
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Mari Yotsu‐Yamashita
- Graduate School of Agriculture Science Tohoku University 468-1 Aramaki-Aza-Aoba, Aoba-ku Sendai 980-8572 Japan
| | - Kazuo Nagasawa
- Department of Biotechnology and Life Science Faculty of Technology Tokyo University of Agriculture and Technology 2-24-16 Naka-cho Koganei Tokyo 184-8588 Japan
| |
Collapse
|
17
|
Yi X, Zhang K, Liu R, Giesy JP, Li Z, Li W, Zhan J, Liu L, Gong Y. Transcriptomic responses of Artemia salina exposed to an environmentally relevant dose of Alexandrium minutum cells or Gonyautoxin2/3. CHEMOSPHERE 2020; 238:124661. [PMID: 31472350 DOI: 10.1016/j.chemosphere.2019.124661] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/10/2019] [Accepted: 08/23/2019] [Indexed: 06/10/2023]
Abstract
Toxicities of the marine algae Alexandrium minutum and its excreted gonyautoxins (GTXs) to the marine crustacean Artemia salina were investigated. Mortality was observed for neither larvae nor adult A. salina exposed to A. minutum at a density of 5000 cells/mL or 0.5 μM GTX2/3. After exposure, the full transcriptome of adult A. salina was assembled and functionally annotated. A total of 599,286 transcripts were obtained, which were clustered into 515,196 unigenes. Results of the transcriptional effect level index revealed that direct exposure to the toxic algae A. minutum caused greater alterations in the transcriptome than did exposure to the extracellular product GTX2/3. Mechanisms of effects were different between exposure of A. salina to A. minutum cells or GTX2/3. Exposure to A. minutum modulated formation of the ribonucleoprotein complex and metabolism of amino acids and lipids in A. salina. Exposure to GTX2/3 exposure inhibited expression of genes related to metabolism of chitin, which might result in disruption of molting process or disturbed sheath morphogenesis. Overall, effects on transcription observed in this study represent the first report based on application of next generation sequencing techniques to investigate the transcriptomic response of A. salina exposed to an environmentally realistic level of A. minutum or GTX2/3.
Collapse
Affiliation(s)
- Xianliang Yi
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Keke Zhang
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Renyan Liu
- National Marine Environmental Monitoring Center, Dalian City, Liaoning, China.
| | - John P Giesy
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon SK, S7N 5B4, Saskatchewan, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon SK, S7N 5B4, Saskatchewan, Canada; Department of Environmental Science, Baylor University, Waco, TX, United States
| | - Zhaochuan Li
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Wentao Li
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Jingjing Zhan
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Lifen Liu
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China
| | - Yufeng Gong
- School of Food and Environment, Dalian University of Technology, Panjin Campus, Panjin City, Liaoning, China; Toxicology Centre, University of Saskatchewan, Saskatoon SK, S7N 5B4, Saskatchewan, Canada.
| |
Collapse
|
18
|
Aballay-González A, Gallardo-Rodriguez JJ, Silva-Higuera M, Rivera A, Ulloa V, Delgado-Rivera L, Rivera-Belmar A, Astuya A. Neuro-2a cell-based assay for toxicity equivalency factor - proposal and evaluation in Chilean contaminated shellfish samples. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2019; 37:162-173. [DOI: 10.1080/19440049.2019.1676919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ambbar Aballay-González
- Laboratorio de Biotoxinas UdeC, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Centro de Investigación Oceanográfica COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| | | | - Macarena Silva-Higuera
- Laboratorio de Biotoxinas UdeC, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Centro de Investigación Oceanográfica COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| | - Alejandra Rivera
- Laboratorio de Biotoxinas UdeC, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Centro de Investigación Oceanográfica COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| | - Viviana Ulloa
- Laboratorio de Biotoxinas UdeC, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Lorena Delgado-Rivera
- Laboratorio de Toxinas Marinas y Micotoxinas, Sección de Química de Alimentos, Departamento de Salud Ambiental, Instituto de Salud Pública de Chile, Ñuñoa, Chile
| | - Andrea Rivera-Belmar
- Departamento de Alimentación y Nutrición, División de Salud y Política Pública, Subsecretaría de Salud Pública, Ministerio de Salud, Santiago, Chile
| | - Allisson Astuya
- Laboratorio de Biotoxinas UdeC, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Centro de Investigación Oceanográfica COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| |
Collapse
|
19
|
Mulcahy JV, Pajouhesh H, Beckley JT, Delwig A, Bois JD, Hunter JC. Challenges and Opportunities for Therapeutics Targeting the Voltage-Gated Sodium Channel Isoform Na V1.7. J Med Chem 2019; 62:8695-8710. [PMID: 31012583 PMCID: PMC6786914 DOI: 10.1021/acs.jmedchem.8b01906] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Voltage-gated sodium ion channel subtype 1.7 (NaV1.7) is a high interest target for the discovery of non-opioid analgesics. Compelling evidence from human genetic data, particularly the finding that persons lacking functional NaV1.7 are insensitive to pain, has spurred considerable effort to develop selective inhibitors of this Na+ ion channel target as analgesic medicines. Recent clinical setbacks and disappointing performance of preclinical compounds in animal pain models, however, have led to skepticism around the potential of selective NaV1.7 inhibitors as human therapeutics. In this Perspective, we discuss the attributes and limitations of recently disclosed investigational drugs targeting NaV1.7 and review evidence that, by better understanding the requirements for selectivity and target engagement, the opportunity to deliver effective analgesic medicines targeting NaV1.7 endures.
Collapse
Affiliation(s)
- John V. Mulcahy
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - Hassan Pajouhesh
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - Jacob T. Beckley
- SiteOne Therapeutics, 351 Evergreen Drive, Suite B1, Bozeman, MT 59715
| | - Anton Delwig
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - J. Du Bois
- Stanford University, Lokey Chemistry and Biology, 337 Campus Drive, Stanford, CA 94305
| | - John C. Hunter
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| |
Collapse
|
20
|
Lukowski AL, Denomme N, Hinze ME, Hall S, Isom LL, Narayan ARH. Biocatalytic Detoxification of Paralytic Shellfish Toxins. ACS Chem Biol 2019; 14:941-948. [PMID: 30983320 PMCID: PMC6528162 DOI: 10.1021/acschembio.9b00123] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
Small molecules that bind to voltage-gated
sodium channels (VGSCs)
are promising leads in the treatment of numerous neurodegenerative
diseases and pain. Nature is a highly skilled medicinal chemist in
this regard, designing potent VGSC ligands capable of binding to and
blocking the channel, thereby offering compounds of potential therapeutic
interest. Paralytic shellfish toxins (PSTs), produced by cyanobacteria
and marine dinoflagellates, are examples of these naturally occurring
small molecule VGSC blockers that can potentially be leveraged to
solve human health concerns. Unfortunately, the remarkable potency
of these natural products results in equally exceptional toxicity,
presenting a significant challenge for the therapeutic application
of these compounds. Identifying less potent analogs and convenient
methods for accessing them therefore provides an attractive approach
to developing molecules with enhanced therapeutic potential. Fortunately,
Nature has evolved tools to modulate the toxicity of PSTs through
selective hydroxylation, sulfation, and desulfation of the core scaffold.
Here, we demonstrate the function of enzymes encoded in cyanobacterial
PST biosynthetic gene clusters that have evolved specifically for
the sulfation of highly functionalized PSTs, the substrate scope of
these enzymes, and elucidate the biosynthetic route from saxitoxin
to monosulfated gonyautoxins and disulfated C-toxins. Finally, the
binding affinities of the nonsulfated, monosulfated, and disulfated
products of these enzymatic reactions have been evaluated for VGSC
binding affinity using mouse whole brain membrane preparations to
provide an assessment of relative toxicity. These data demonstrate
the unique detoxification effect of sulfotransferases in PST biosynthesis,
providing a potential mechanism for the development of more attractive
PST-derived therapeutic analogs.
Collapse
Affiliation(s)
| | | | | | - Sherwood Hall
- United States Food and Drug Administration, College Park, Maryland 20740, United States
| | | | | |
Collapse
|
21
|
Valenzuela C, Torres C, Muñoz V, Simbaina JC, Sánchez A, Bustamante T, Sepúlveda JM, Piron R, Del Campo M, Lagos N. Evaluation of Neosaxitoxin as a local anesthetic during piglet castration: A potential alternative for Lidocaine. Toxicon 2019; 164:26-30. [PMID: 30951754 DOI: 10.1016/j.toxicon.2019.03.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 03/08/2019] [Accepted: 03/31/2019] [Indexed: 11/18/2022]
Abstract
OBJETIVE To evaluate Neosaxitoxin (NeoSTX) as a local anesthetic drug, for pain control during and after piglet castration. STUDY DESIGN Prospective, randomized and double-blind study. ANIMALS 24 commercial hybrids, males, 23-day-old piglets. METHODS The piglets were randomized into two groups: a Lidocaine group and a NeoSTX group. One minute before castration, they were injected intra-scrotally with a single dose of Lidocaine (20 mg, in 1 mL) and NeoSTX (0.1 μg, in 1 mL), respectively. RESULTS NeoSTX does not generate vasoconstriction or scrotal contraction, unlike Lidocaine, where a decrease in temperature and scrotal size is observed within 5 min after the procedure. After 24 h, wound inflammation, as measured by scrotal size, was lower in the NeoSTX group. No significant difference could be shown between the vocalizations and facial expressions of pain of both groups during the castration procedure. CONCLUSIONS A single dose of NeoSTX is safe and effective for pain management during and after piglet castration. NeoSTX treated piglets were less affected by castration than those in the Lidocaine group, thus reducing piglet stress and enhancing the quality of piglet convalescence.
Collapse
Affiliation(s)
- Carolina Valenzuela
- Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, 8820808, Chile.
| | - Cristian Torres
- Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, 8820808, Chile.
| | - Vanina Muñoz
- Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, 8820808, Chile.
| | - Juan Carlos Simbaina
- Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, 8820808, Chile.
| | - Andrella Sánchez
- Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, 8820808, Chile.
| | - Tamara Bustamante
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Joaquín M Sepúlveda
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Robin Piron
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Miguel Del Campo
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, Santiago, 8389100, Chile.
| | - Néstor Lagos
- Membrane Biochemistry Laboratory, Department of Physiology and Biophysics, Faculty of Medicine, University of Chile, Independencia 1027, Santiago, 8389100, Chile.
| |
Collapse
|
22
|
Reis Costa P, Braga AC, Turner AD. Accumulation and Elimination Dynamics of the Hydroxybenzoate Saxitoxin Analogues in Mussels Mytilus galloprovincialis Exposed to the Toxic Marine Dinoflagellate Gymnodinium catenatum. Toxins (Basel) 2018; 10:toxins10110428. [PMID: 30373104 PMCID: PMC6267569 DOI: 10.3390/toxins10110428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 10/09/2018] [Accepted: 10/23/2018] [Indexed: 01/23/2023] Open
Abstract
Paralytic shellfish poisoning (PSP) is a severe food-borne illness, caused by the ingestion of seafood containing paralytic shellfish toxins (PST), which are naturally produced by marine dinoflagellates and accumulate in shellfish during algae blooms. Novel PST, designated as hydroxybenzoate analogues (also known as GC toxins), was relatively recently discovered in Gymnodinium catenatum strains worldwide. However, to date, there have been no studies examining their accumulation in shellfish. In this study, mussels (Mytilus galloprovincialis) were exposed to G. catenatum for five days and then exposed to a non-toxic diet for 24 h, to investigate the toxin’s accumulation/elimination dynamics. As determined by UHPLC-HILIC-MS/MS, the hydroxybenzoate analogues, GC1 to GC6, comprised 41% of the algae toxin profile and only 9% in mussels. Elimination of GC toxins after 24 h was not evident. This study highlights that a relevant fraction of PST in mussels are not routinely analysed in monitoring programs and that there is a need to better understand the toxicological potential of the hydroxybenzoate analogues, in order to properly address the risk of G. catenatum blooms.
Collapse
Affiliation(s)
- Pedro Reis Costa
- IPMA-Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal.
- CCMAR-Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139 Faro, Portugal.
| | - Ana Catarina Braga
- IPMA-Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal.
- Biology Department and CESAM, Aveiro University, 3810-193 Aveiro, Portugal.
| | - Andrew D Turner
- Centre for Environment Fisheries and Aquaculture Science (CEFAS), Barrack Road, Weymouth, Dorset DT4 8UB, UK.
| |
Collapse
|
23
|
|
24
|
Xu J, Hansen PJ, Nielsen LT, Krock B, Tillmann U, Kiørboe T. Distinctly different behavioral responses of a copepod, Temora longicornis, to different strains of toxic dinoflagellates, Alexandrium spp. HARMFUL ALGAE 2017; 62:1-9. [PMID: 28118883 DOI: 10.1016/j.hal.2016.11.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 11/29/2016] [Accepted: 11/29/2016] [Indexed: 06/06/2023]
Abstract
Zooplankton responses to toxic algae are highly variable, even towards taxonomically closely related species or different strains of the same species. Here, the individual level feeding behavior of a copepod, Temora longicornis, was examined which offered 4 similarly sized strains of toxic dinoflagellate Alexandrium spp. and a non-toxic control strain of the dinoflagellate Protoceratium reticulatum. The strains varied in their cellular toxin concentration and composition and in lytic activity. High-speed video observations revealed four distinctly different strain-specific feeding responses of the copepod during 4h incubations: (i) the 'normal' feeding behavior, in which the feeding appendages were beating almost constantly to produce a feeding current and most (90%) of the captured algae were ingested; (ii) the beating activity of the feeding appendages was reduced by ca. 80% during the initial 60min of exposure, after which very few algae were captured and ingested; (iii) capture and ingestion rates remained high, but ingested cells were regurgitated; and (iv) the copepod continued beating its appendages and captured cells at a high rate, but after 60min, most captured cells were rejected. The various prey aversion responses observed may have very different implications to the prey and their ability to form blooms: consumed but regurgitated cells are dead, captured but rejected cells survive and may give the prey a competitive advantage, while reduced feeding activity of the grazer may be equally beneficial to the prey and its competitors. These behaviors were not related to lytic activity or overall paralytic shellfish toxins (PSTs) content and composition and suggest that other cues are responsible for the responses.
Collapse
Affiliation(s)
- Jiayi Xu
- Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, 2920 Charlottenlund, Denmark; Key and Open Laboratory of Marine and Estuary Fisheries, Ministry of Agriculture of China, East China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, 200090 Shanghai, China.
| | - Per Juel Hansen
- Marine Biological Section, University of Copenhagen, 3000 Helsingør, Denmark
| | - Lasse Tor Nielsen
- Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, 2920 Charlottenlund, Denmark
| | - Bernd Krock
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung, 27570 Bremerhaven, Germany
| | - Urban Tillmann
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung, 27570 Bremerhaven, Germany
| | - Thomas Kiørboe
- Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, 2920 Charlottenlund, Denmark
| |
Collapse
|
25
|
Buratti FM, Manganelli M, Vichi S, Stefanelli M, Scardala S, Testai E, Funari E. Cyanotoxins: producing organisms, occurrence, toxicity, mechanism of action and human health toxicological risk evaluation. Arch Toxicol 2017; 91:1049-1130. [DOI: 10.1007/s00204-016-1913-6] [Citation(s) in RCA: 258] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 12/13/2016] [Indexed: 12/11/2022]
|
26
|
The association of bacterial C 9-based TTX-like compounds with Prorocentrum minimum opens new uncertainties about shellfish seafood safety. Sci Rep 2017; 7:40880. [PMID: 28106083 PMCID: PMC5247728 DOI: 10.1038/srep40880] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/12/2016] [Indexed: 12/23/2022] Open
Abstract
In 2012, Tetrodotoxin (TTX) was identified in mussels and linked to the presence of Prorocentrum minimum (P. minimum) in Greece. The connexion between TTX and P. minimum was further studied in this paper. First, the presence of TTX-producer bacteria, Vibrio and Pseudomonas spp, was confirmed in Greek mussels. In addition these samples showed high activity as inhibitors of sodium currents (INa). P. minimum was before associated with neurotoxic symptoms, however, the nature and structure of toxins produced by this dinoflagellate remains unknown. Three P. minimum strains, ccmp1529, ccmp2811 and ccmp2956, growing in different conditions of temperature, salinity and light were used to study the production of toxic compounds. Electrophysiological assays showed no effect of ccmp2811 strain on INa, while ccmp1529 and ccmp2956 strains were able to significantly reduce INa in the same way as TTX. In these samples two new compounds, m/z 265 and m/z 308, were identified and characterized by liquid chromatography tandem high-resolution mass spectrometry. Besides, two TTX-related bacteria, Roseobacter and Vibrio sp, were observed. These results show for the first time that P. minimum produce TTX-like compounds with a similar ion pattern and C9-base to TTX analogues and with the same effect on INa.
Collapse
|
27
|
Botana LM, Hess P, Munday R, Nathalie A, DeGrasse SL, Feeley M, Suzuki T, van den Berg M, Fattori V, Garrido Gamarro E, Tritscher A, Nakagawa R, Karunasagar I. Derivation of toxicity equivalency factors for marine biotoxins associated with Bivalve Molluscs. Trends Food Sci Technol 2017. [DOI: 10.1016/j.tifs.2016.09.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
28
|
How Safe Is Safe for Marine Toxins Monitoring? Toxins (Basel) 2016; 8:toxins8070208. [PMID: 27399774 PMCID: PMC4963841 DOI: 10.3390/toxins8070208] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 06/27/2016] [Accepted: 07/01/2016] [Indexed: 11/17/2022] Open
Abstract
Current regulation for marine toxins requires a monitoring method based on mass spectrometric analysis. This method is pre-targeted, hence after searching for pre-assigned masses, it identifies those compounds that were pre-defined with available calibrants. Therefore, the scope for detecting novel toxins which are not included in the monitoring protocol are very limited. In addition to this, there is a poor comprehension of the toxicity of some marine toxin groups. Also, the validity of the current approach is questioned by the lack of sufficient calibrants, and by the insufficient coverage by current legislation of the toxins reported to be present in shellfish. As an example, tetrodotoxin, palytoxin analogs, or cyclic imines are mentioned as indicators of gaps in the system that require a solid comprehension to assure consumers are protected.
Collapse
|
29
|
Rey V, Botana AM, Alvarez M, Antelo A, Botana LM. Liquid Chromatography with a Fluorimetric Detection Method for Analysis of Paralytic Shellfish Toxins and Tetrodotoxin Based on a Porous Graphitic Carbon Column. Toxins (Basel) 2016; 8:toxins8070196. [PMID: 27367728 PMCID: PMC4963829 DOI: 10.3390/toxins8070196] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 01/12/2023] Open
Abstract
Paralytic shellfish toxins (PST) traditionally have been analyzed by liquid chromatography with either pre- or post-column derivatization and always with a silica-based stationary phase. This technique resulted in different methods that need more than one run to analyze the toxins. Furthermore, tetrodotoxin (TTX) was recently found in bivalves of northward locations in Europe due to climate change, so it is important to analyze it along with PST because their signs of toxicity are similar in the bioassay. The methods described here detail a new approach to eliminate different runs, by using a new porous graphitic carbon stationary phase. Firstly we describe the separation of 13 PST that belong to different groups, taking into account the side-chains of substituents, in one single run of less than 30 min with good reproducibility. The method was assayed in four shellfish matrices: mussel (Mytillus galloprovincialis), clam (Pecten maximus), scallop (Ruditapes decussatus) and oyster (Ostrea edulis). The results for all of the parameters studied are provided, and the detection limits for the majority of toxins were improved with regard to previous liquid chromatography methods: the lowest values were those for decarbamoyl-gonyautoxin 2 (dcGTX2) and gonyautoxin 2 (GTX2) in mussel (0.0001 mg saxitoxin (STX)·diHCl kg−1 for each toxin), decarbamoyl-saxitoxin (dcSTX) in clam (0.0003 mg STX·diHCl kg−1), N-sulfocarbamoyl-gonyautoxins 2 and 3 (C1 and C2) in scallop (0.0001 mg STX·diHCl kg−1 for each toxin) and dcSTX (0.0003 mg STX·diHCl kg−1 ) in oyster; gonyautoxin 2 (GTX2) showed the highest limit of detection in oyster (0.0366 mg STX·diHCl kg−1). Secondly, we propose a modification of the method for the simultaneous analysis of PST and TTX, with some minor changes in the solvent gradient, although the detection limit for TTX does not allow its use nowadays for regulatory purposes.
Collapse
Affiliation(s)
- Veronica Rey
- Department Analytical Chemistry, Faculty of Sciences, University of Santiago de Compostela, Lugo 27002, Spain.
| | - Ana M Botana
- Department Analytical Chemistry, Faculty of Sciences, University of Santiago de Compostela, Lugo 27002, Spain.
| | | | - Alvaro Antelo
- CIFGA S.A., Plaza Santo Domingo 20-5ª, Lugo 27001, Spain.
| | - Luis M Botana
- Department Pharmacology, Veterinary Faculty, University of Santiago de Compostela, Lugo 27002, Spain.
| |
Collapse
|
30
|
Mutant cycle analysis with modified saxitoxins reveals specific interactions critical to attaining high-affinity inhibition of hNaV1.7. Proc Natl Acad Sci U S A 2016; 113:5856-61. [PMID: 27162340 DOI: 10.1073/pnas.1603486113] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Improper function of voltage-gated sodium channels (NaVs), obligatory membrane proteins for bioelectrical signaling, has been linked to a number of human pathologies. Small-molecule agents that target NaVs hold considerable promise for treatment of chronic disease. Absent a comprehensive understanding of channel structure, the challenge of designing selective agents to modulate the activity of NaV subtypes is formidable. We have endeavored to gain insight into the 3D architecture of the outer vestibule of NaV through a systematic structure-activity relationship (SAR) study involving the bis-guanidinium toxin saxitoxin (STX), modified saxitoxins, and protein mutagenesis. Mutant cycle analysis has led to the identification of an acetylated variant of STX with unprecedented, low-nanomolar affinity for human NaV1.7 (hNaV1.7), a channel subtype that has been implicated in pain perception. A revised toxin-receptor binding model is presented, which is consistent with the large body of SAR data that we have obtained. This new model is expected to facilitate subsequent efforts to design isoform-selective NaV inhibitors.
Collapse
|
31
|
Durán-Riveroll LM, Cembella AD, Band-Schmidt CJ, Bustillos-Guzmán JJ, Correa-Basurto J. Docking Simulation of the Binding Interactions of Saxitoxin Analogs Produced by the Marine Dinoflagellate Gymnodinium catenatum to the Voltage-Gated Sodium Channel Nav1.4. Toxins (Basel) 2016; 8:toxins8050129. [PMID: 27164145 PMCID: PMC4885044 DOI: 10.3390/toxins8050129] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 04/10/2016] [Accepted: 04/13/2016] [Indexed: 01/26/2023] Open
Abstract
Saxitoxin (STX) and its analogs are paralytic alkaloid neurotoxins that block the voltage-gated sodium channel pore (Nav), impeding passage of Na+ ions into the intracellular space, and thereby preventing the action potential in the peripheral nervous system and skeletal muscle. The marine dinoflagellate Gymnodinium catenatum produces an array of such toxins, including the recently discovered benzoyl analogs, for which the mammalian toxicities are essentially unknown. We subjected STX and its analogs to a theoretical docking simulation based upon two alternative tri-dimensional models of the Nav1.4 to find a relationship between the binding properties and the known mammalian toxicity of selected STX analogs. We inferred hypothetical toxicities for the benzoyl analogs from the modeled values. We demonstrate that these toxins exhibit different binding modes with similar free binding energies and that these alternative binding modes are equally probable. We propose that the principal binding that governs ligand recognition is mediated by electrostatic interactions. Our simulation constitutes the first in silico modeling study on benzoyl-type paralytic toxins and provides an approach towards a better understanding of the mode of action of STX and its analogs.
Collapse
Affiliation(s)
- Lorena M Durán-Riveroll
- Departamento de Plancton y Ecología Marina, Centro Interdisciplinario de Ciencias Marinas-Instituto Politécnico Nacional, La Paz, B. C. S. 23096, Mexico.
| | - Allan D Cembella
- Alfred-Wegener-Institut, Helmholtz Zentrum für Polar-und Meeresforschung, Bremerhaven 27570, Germany.
| | - Christine J Band-Schmidt
- Departamento de Plancton y Ecología Marina, Centro Interdisciplinario de Ciencias Marinas-Instituto Politécnico Nacional, La Paz, B. C. S. 23096, Mexico.
| | | | - José Correa-Basurto
- Laboratorio de Modelado Molecular y Diseño de Fármacos, Escuela Superior de Medicina-Instituto Politécnico Nacional, Mexico City 11340, Mexico.
| |
Collapse
|
32
|
Mulcahy JV, Walker JR, Merit JE, Whitehead A, Du Bois J. Synthesis of the Paralytic Shellfish Poisons (+)-Gonyautoxin 2, (+)-Gonyautoxin 3, and (+)-11,11-Dihydroxysaxitoxin. J Am Chem Soc 2016; 138:5994-6001. [PMID: 27138488 DOI: 10.1021/jacs.6b02343] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The paralytic shellfish poisons are a collection of guanidine-containing natural products that are biosynthesized by prokaryote and eukaryote marine organisms. These compounds bind and inhibit isoforms of the mammalian voltage-gated Na(+) ion channel at concentrations ranging from 10(-11) to 10(-5) M. Here, we describe the de novo synthesis of three paralytic shellfish poisons, gonyautoxin 2, gonyautoxin 3, and 11,11-dihydroxysaxitoxin. Key steps include a diastereoselective Pictet-Spengler reaction and an intramolecular amination of an N-guanidyl pyrrole by a sulfonyl guanidine. The IC50's of GTX 2, GTX 3, and 11,11-dhSTX have been measured against rat NaV1.4, and are found to be 22 nM, 15 nM, and 2.2 μM, respectively.
Collapse
Affiliation(s)
- John V Mulcahy
- Department of Chemistry, Stanford University , Stanford, California 94305-0080, United States
| | - James R Walker
- Department of Chemistry, Stanford University , Stanford, California 94305-0080, United States
| | - Jeffrey E Merit
- Department of Chemistry, Stanford University , Stanford, California 94305-0080, United States
| | - Alan Whitehead
- Department of Chemistry, Stanford University , Stanford, California 94305-0080, United States
| | - J Du Bois
- Department of Chemistry, Stanford University , Stanford, California 94305-0080, United States
| |
Collapse
|