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Dinh LTQ, Do GTC, Ngo TK, Nguyen TD, Nguyen HM, Nguyen PQ, Khe NH, Dang HP, Nguyen VT, Dao NH, Truong ULN, Vu PM. A 15-Year Experience With Total Anomalous Pulmonary Venous Connection in Vietnam. World J Pediatr Congenit Heart Surg 2024:21501351231215256. [PMID: 38263638 DOI: 10.1177/21501351231215256] [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] [Indexed: 01/25/2024]
Abstract
BACKGROUND This article aims to demonstrate the morphology of 261 total anomalous pulmonary venous connection (TAPVC) cases operated at Children's Hospital 1 with in-hospital mortality of 19.5% (51/261). METHODS All the surgical protocols of TAPVC cases repaired between 2008 and June 2023 were reviewed. The descriptions of TAPVC were based on operative findings by surgeons. RESULTS A total of 261 TAPVC patients were operated, including 124 (47.5%) supra, 83 (31.8%) intra, 41 (15.7%) infra, and 13 (5%) mixed cases. The in-hospital mortality was 19.5% (51/261). Fifteen cases are associated with other anomalies of the heart. Four subtypes of 124 supra TAPVC were found, with 42 (33.9%) obstructed cases. The standard was all pulmonary veins (PVs) forming a common vein (CV) and draining into the innominate veins, then going to the superior vena cava (SVC) (100/124, 80.6%). Eleven supra TAPVC cases were vascular vise type. Ten cases had the vertical vein running from the right of the CV and draining directly into the SVC. Of 83 intracardiac TAPVCs with 9 (10.8%) obstructed cases, the most common was all PVs draining directly into the coronary sinus (60/83, 72.3%). The second was all PVs draining directly into the right atrium (RA) via separated ostia or forming a CV before entering the RA (17/83, 20.5%). Also, there were three cases with rare variants and 100% obstruction when the diagnosis was explored. The in-hospital mortality of intracardiac type was 13.3% (11/83) 41 infra TAPVC with obstructed rate of 61% (25/41) and in-hospital mortality of 29.3% (12/41). Thirteen mixed TAPVCs were repaired, with most cases having three PVs forming a CV. CONCLUSION This article provides valuable information about the morphology of TAPVC types in Asian patients.
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Affiliation(s)
- Le-Thanh Q Dinh
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Giang T C Do
- Cardiology Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Thoi K Ngo
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Tuan D Nguyen
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Hai M Nguyen
- Cardiology Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Phat Q Nguyen
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Nguyen H Khe
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Hung P Dang
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Vu T Nguyen
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Nha H Dao
- Cardiac Surgery Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Uy-Linh N Truong
- Pediatric Surgery Department, University of Medicine and Pharmacy in HCMC, Ho Chi Minh City, Vietnam
| | - Phuc M Vu
- Cardiology Department, Children's Hospital 1, Ho Chi Minh City, Vietnam
- Cardiology Department, University of Medicine and Pharmacy in HCMC, Ho Chi Minh City, Vietnam
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Lee RD, Chen YJ, Singh L, Nguyen HM, Wulff H. Immunocytoprotection after reperfusion with Kv1.3 inhibitors has an extended treatment window for ischemic stroke. Front Pharmacol 2023; 14:1190476. [PMID: 37180699 PMCID: PMC10166874 DOI: 10.3389/fphar.2023.1190476] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 04/17/2023] [Indexed: 05/16/2023] Open
Abstract
Introduction: Mechanical thrombectomy has improved treatment options and outcomes for acute ischemic stroke with large artery occlusion. However, as the time window of endovascular thrombectomy is extended there is an increasing need to develop immunocytoprotective therapies that can reduce inflammation in the penumbra and prevent reperfusion injury. We previously demonstrated, that by reducing neuroinflammation, KV1.3 inhibitors can improve outcomes not only in young male rodents but also in female and aged animals. To further explore the therapeutic potential of KV1.3 inhibitors for stroke therapy, we here directly compared a peptidic and a small molecule KV1.3 blocker and asked whether KV1.3 inhibition would still be beneficial when started at 72 hours after reperfusion. Methods: Transient middle cerebral artery occlusion (tMCAO, 90-min) was induced in male Wistar rats and neurological deficit assessed daily. On day-8 infarction was determined by T2-weighted MRI and inflammatory marker expression in the brain by quantitative PCR. Potential interactions with tissue plasminogen activator (tPA) were evaluated in-vitro with a chromogenic assay. Results: In a direct comparison with administration started at 2 hours after reperfusion, the small molecule PAP-1 significantly improved outcomes on day-8, while the peptide ShK-223 failed to reduce infarction and neurological deficits despite reducing inflammatory marker expression. PAP-1 still provided benefits when started 72 hours after reperfusion. PAP-1 does not reduce the proteolytic activity of tPA. Discussion: Our studies suggest that KV1.3 inhibition for immunocytoprotection after ischemic stroke has a wide therapeutic window for salvaging the inflammatory penumbra and requires brain-penetrant small molecules.
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Affiliation(s)
- Ruth D. Lee
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Yi-Je Chen
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
- Animal Models Core, Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Latika Singh
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Hai M. Nguyen
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
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3
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Lee RD, Chen YJ, Nguyen HM, Singh L, Dietrich CJ, Pyles BR, Cui Y, Weinstein JR, Wulff H. Repurposing the K Ca3.1 Blocker Senicapoc for Ischemic Stroke. Transl Stroke Res 2023:10.1007/s12975-023-01152-6. [PMID: 37088858 DOI: 10.1007/s12975-023-01152-6] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/25/2023]
Abstract
Senicapoc, a small molecule inhibitor of the calcium-activated potassium channel KCa3.1, was safe and well-tolerated in clinical trials for sickle cell anemia. We previously reported proof-of-concept data suggesting that both pharmacological inhibition and genetic deletion of KCa3.1 reduces infarction and improves neurologic recovery in rodents by attenuating neuroinflammation. Here we evaluated the potential of repurposing senicapoc for ischemic stroke. In cultured microglia, senicapoc inhibited KCa3.1 currents with an IC50 of 7 nM, reduced Ca2+ signaling induced by the purinergic agonist ATP, suppressed expression of pro-inflammatory cytokines and enzymes (iNOS and COX-2), and prevented induction of the inflammasome component NLRP3. When transient middle cerebral artery occlusion (tMCAO, 60 min) was induced in male C57BL/6 J mice, twice daily administration of senicapoc at 10 and 40 mg/kg starting 12 h after reperfusion dose-dependently reduced infarct area determined by T2-weighted magnetic resonance imaging (MRI) and improved neurological deficit on day 8. Ultra-high-performance liquid chromatography/mass spectrometry analysis of total and free brain concentrations demonstrated sufficient KCa3.1 target engagement. Senicapoc treatment significantly reduced microglia/macrophage and T cell infiltration and activation and attenuated neuronal death. A different treatment paradigm with senicapoc started at 3 h and MRI on day 3 and day 8 revealed that senicapoc reduces secondary infarct growth and suppresses expression of inflammation markers, including T cell cytokines in the brain. Lastly, we demonstrated that senicapoc does not impair the proteolytic activity of tissue plasminogen activator (tPA) in vitro. We suggest that senicapoc could be repurposed as an adjunctive immunocytoprotective agent for combination with reperfusion therapy for ischemic stroke.
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Affiliation(s)
- Ruth D Lee
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Yi-Je Chen
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
- Animal Models Core, Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Hai M Nguyen
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Latika Singh
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Connor J Dietrich
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Benjamin R Pyles
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Yanjun Cui
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Jonathan R Weinstein
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, 95616, USA.
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4
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Nguyen PT, Nguyen HM, Wagner KM, Stewart R, Singh V, Thapa P, Tuan Ton A, Kondo RP, Ghetti A, Pennington MW, Hammock B, Griffith TN, Sack JT, Wulff H, Yarov-Yarovoy V. Computational design of peptides to target Na v1.7 channel with high potency and selectivity for the treatment of pain. Biophys J 2023; 122:309a. [PMID: 36783550 DOI: 10.1016/j.bpj.2022.11.1739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Affiliation(s)
- Phuong T Nguyen
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | - Hai M Nguyen
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Karen M Wagner
- Department of Entomology and Nematology, University of California Davis, Davis, CA, USA; Comprehensive Cancer Center, University of California Davis, Davis, CA, USA
| | - Robert Stewart
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | - Vikrant Singh
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Parashar Thapa
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | | | | | | | | | - Bruce Hammock
- Department of Entomology and Nematology, University of California Davis, Davis, CA, USA; Comprehensive Cancer Center, University of California Davis, Davis, CA, USA
| | - Theanne N Griffith
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | - Jon T Sack
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | - Heike Wulff
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Vladimir Yarov-Yarovoy
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
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5
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Srinivasan SR, Huang H, Chang WC, Nasburg JA, Nguyen HM, Strassmaier T, Wulff H, Shakkottai VG. Discovery of Novel Activators of Large-Conductance Calcium-Activated Potassium Channels for the Treatment of Cerebellar Ataxia. Mol Pharmacol 2022; 102:438-449. [PMID: 35489717 PMCID: PMC9341255 DOI: 10.1124/molpharm.121.000478] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 04/07/2022] [Indexed: 01/11/2023] Open
Abstract
Impaired cerebellar Purkinje neuron firing resulting from reduced expression of large-conductance calcium-activated potassium (BK) channels is a consistent feature in models of inherited neurodegenerative spinocerebellar ataxia (SCA). Restoring BK channel expression improves motor function and delays cerebellar degeneration, indicating that BK channels are an attractive therapeutic target. Current BK channel activators lack specificity and potency and are therefore poor templates for future drug development. We implemented an automated patch clamp platform for high-throughput drug discovery of BK channel activators using the Nanion SyncroPatch 384PE system. We screened over 15,000 compounds for their ability to increase BK channel current amplitude under conditions of lower intracellular calcium that is present in disease. We identified several novel BK channel activators that were then retested on the SyncroPatch 384PE to generate concentration-response curves (CRCs). Compounds with favorable CRCs were subsequently tested for their ability to improve irregular cerebellar Purkinje neuron spiking, characteristic of BK channel dysfunction in SCA1 mice. We identified a novel BK channel activator, 4-chloro-N-(5-chloro-2-cyanophenyl)-3-(trifluoromethyl)benzene-1-sulfonamide (herein renamed BK-20), that exhibited a more potent half-maximal activation of BK current (pAC50 = 4.64) than NS-1619 (pAC50 = 3.7) at a free internal calcium concentration of 270 nM in a heterologous expression system and improved spiking regularity in SCA1 Purkinje neurons. BK-20 had no activity on small-conductance calcium-activated potassium (SK)1-3 channels but interestingly was a potent blocker of the T-type calcium channel, Cav3.1 (IC50 = 1.05 μM). Our work describes both a novel compound for further drug development in disorders with irregular Purkinje spiking and a unique platform for drug discovery in degenerative ataxias. SIGNIFICANCE STATEMENT: Motor impairment associated with altered Purkinje cell spiking due to dysregulation of large-conductance calcium-activated potassium (BK) channel expression and function is a shared feature of disease in many degenerative ataxias. BK channel activators represent an outstanding therapeutic agent for ataxia. We have developed a high-throughput platform to screen for BK channel activators and identified a novel compound that can serve as a template for future drug development for the treatment of these disabling disorders.
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Affiliation(s)
- Sharan R Srinivasan
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Haoran Huang
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Wei-Chih Chang
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Joshua A Nasburg
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Hai M Nguyen
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Tim Strassmaier
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Heike Wulff
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
| | - Vikram G Shakkottai
- Brigham and Women's Hospital, Department of Neurology, Boston, Massachusetts (S.R.S.); University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas (H.H., V.G.S.); University of Michigan, Department of Neurology, Ann Arbor, Michigan (S.R.S., W.-C.C.); University of California, Davis, Department of Pharmacology, Davis, California (J.A.N., H.M.N., H.W.); and Nanion Technologies, Munich, Germany (T.S.)
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Thompson DR, Bohn N, Brodrick PG, Carmon N, Eastwood ML, Eckert R, Fichot CG, Harringmeyer JP, Nguyen HM, Simard M, Thorpe AK. Atmospheric Lengthscales for Global VSWIR Imaging Spectroscopy. J Geophys Res Biogeosci 2022; 127:e2021JG006711. [PMID: 35859986 PMCID: PMC9285454 DOI: 10.1029/2021jg006711] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Future global Visible Shortwave Infrared Imaging Spectrometers, such as the Surface Biology and Geology (SBG) mission, will regularly cover the Earth's entire terrestrial land area. These missions need high fidelity atmospheric correction to produce consistent maps of terrestrial and aquatic ecosystem traits. However, estimation of surface reflectance and atmospheric state is computationally challenging, and the terabyte data volumes of global missions will exceed available processing capacity. This article describes how missions can overcome this bottleneck using the spatial continuity of atmospheric fields. Contemporary imaging spectrometers oversample atmospheric spatial variability, so it is not necessary to invert every pixel. Spatially sparse solutions can train local linear emulators that provide fast, exact inversions in their vicinity. We find that estimating the atmosphere at 200 m scales can outperform traditional atmospheric correction, improving speed by one to two orders of magnitude with no measurable penalty to accuracy. We validate performance with an airborne field campaign, showing reflectance accuracies with RMSE of 1.1% or better compared to ground measurements of diverse targets. These errors are statistically consistent with retrieval uncertainty budgets. Local emulators can close the efficiency gap and make rigorous model inversion algorithms feasible for global missions such as SBG.
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Affiliation(s)
- David R Thompson
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Niklas Bohn
- Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam Germany
| | - Philip G Brodrick
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Nimrod Carmon
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Michael L Eastwood
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Regina Eckert
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Cédric G Fichot
- Department of Earth and Environment Boston University Boston MA USA
| | | | - Hai M Nguyen
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Marc Simard
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - Andrew K Thorpe
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
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7
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Nguyen HM, Cui Y, Wulff H. Differential effects of cell-permeable and cell-impermeable Kv1.3 inhibitors on microglial calcium signaling. Biophys J 2022. [DOI: 10.1016/j.bpj.2021.11.269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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8
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Nguyen PT, Nguyen HM, Wagner KM, Stewart RG, Singh V, Thapa P, Chen YJ, Lillya MW, Ton AT, Kondo R, Ghetti A, Pennington MW, Hammock B, Griffith TN, Sack JT, Wulff H, Yarov-Yarovoy V. Computational design of peptides to target Na V1.7 channel with high potency and selectivity for the treatment of pain. eLife 2022; 11:81727. [PMID: 36576241 PMCID: PMC9831606 DOI: 10.7554/elife.81727] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
The voltage-gated sodium NaV1.7 channel plays a key role as a mediator of action potential propagation in C-fiber nociceptors and is an established molecular target for pain therapy. ProTx-II is a potent and moderately selective peptide toxin from tarantula venom that inhibits human NaV1.7 activation. Here we used available structural and experimental data to guide Rosetta design of potent and selective ProTx-II-based peptide inhibitors of human NaV1.7 channels. Functional testing of designed peptides using electrophysiology identified the PTx2-3127 and PTx2-3258 peptides with IC50s of 7 nM and 4 nM for hNaV1.7 and more than 1000-fold selectivity over human NaV1.1, NaV1.3, NaV1.4, NaV1.5, NaV1.8, and NaV1.9 channels. PTx2-3127 inhibits NaV1.7 currents in mouse and human sensory neurons and shows efficacy in rat models of chronic and thermal pain when administered intrathecally. Rationally designed peptide inhibitors of human NaV1.7 channels have transformative potential to define a new class of biologics to treat pain.
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Affiliation(s)
- Phuong T Nguyen
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States
| | - Hai M Nguyen
- Department of Pharmacology, University of California DavisDavisUnited States
| | - Karen M Wagner
- Department of Entomology and Nematology & Comprehensive Cancer Center, University of California DavisDavisUnited States
| | - Robert G Stewart
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States
| | - Vikrant Singh
- Department of Pharmacology, University of California DavisDavisUnited States
| | - Parashar Thapa
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States
| | - Yi-Je Chen
- Department of Pharmacology, University of California DavisDavisUnited States
| | - Mark W Lillya
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States
| | | | | | | | | | - Bruce Hammock
- Department of Entomology and Nematology & Comprehensive Cancer Center, University of California DavisDavisUnited States
| | - Theanne N Griffith
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States
| | - Jon T Sack
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States,Department of Anesthesiology and Pain Medicine, University of California DavisDavisUnited States
| | - Heike Wulff
- Department of Pharmacology, University of California DavisDavisUnited States
| | - Vladimir Yarov-Yarovoy
- Department of Physiology and Membrane Biology, University of California DavisDavisUnited States,Department of Anesthesiology and Pain Medicine, University of California DavisDavisUnited States,Biophysics Graduate Group, University of California DavisDavisUnited States
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9
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Sarkar S, Nguyen HM, Malovic E, Luo J, Langley M, Palanisamy BN, Singh N, Manne S, Neal M, Gabrielle M, Abdalla A, Anantharam P, Rokad D, Panicker N, Singh V, Ay M, Charli A, Harischandra D, Jin LW, Jin H, Rangaraju S, Anantharam V, Wulff H, Kanthasamy AG. Kv1.3 modulates neuroinflammation and neurodegeneration in Parkinson's disease. J Clin Invest 2021; 130:4195-4212. [PMID: 32597830 DOI: 10.1172/jci136174] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [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: 01/09/2020] [Accepted: 04/29/2020] [Indexed: 12/15/2022] Open
Abstract
Characterization of the key cellular targets contributing to sustained microglial activation in neurodegenerative diseases, including Parkinson's disease (PD), and optimal modulation of these targets can provide potential treatments to halt disease progression. Here, we demonstrated that microglial Kv1.3, a voltage-gated potassium channel, was transcriptionally upregulated in response to aggregated α-synuclein (αSynAgg) stimulation in primary microglial cultures and animal models of PD, as well as in postmortem human PD brains. Patch-clamp electrophysiological studies confirmed that the observed Kv1.3 upregulation translated to increased Kv1.3 channel activity. The kinase Fyn, a risk factor for PD, modulated transcriptional upregulation and posttranslational modification of microglial Kv1.3. Multiple state-of-the-art analyses, including Duolink proximity ligation assay imaging, revealed that Fyn directly bound to Kv1.3 and posttranslationally modified its channel activity. Furthermore, we demonstrated the functional relevance of Kv1.3 in augmenting the neuroinflammatory response by using Kv1.3-KO primary microglia and the Kv1.3-specific small-molecule inhibitor PAP-1, thus highlighting the importance of Kv1.3 in neuroinflammation. Administration of PAP-1 significantly inhibited neurodegeneration and neuroinflammation in multiple animal models of PD. Collectively, our results imply that Fyn-dependent regulation of Kv1.3 channels plays an obligatory role in accentuating the neuroinflammatory response in PD and identify Kv1.3 as a potential therapeutic target for PD.
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Affiliation(s)
- Souvarish Sarkar
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Hai M Nguyen
- Department of Pharmacology, School of Medicine, UCD, Davis, California, USA
| | - Emir Malovic
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Jie Luo
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Monica Langley
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Bharathi N Palanisamy
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Neeraj Singh
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Sireesha Manne
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Matthew Neal
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Michelle Gabrielle
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
| | - Ahmed Abdalla
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Poojya Anantharam
- Department of Veterinary Diagnostic and Production Animal Medicine, Veterinary Medicine Building, ISU, Ames, Iowa, USA
| | - Dharmin Rokad
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Nikhil Panicker
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Vikrant Singh
- Department of Pharmacology, School of Medicine, UCD, Davis, California, USA
| | - Muhammet Ay
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Adhithiya Charli
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Dilshan Harischandra
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Lee-Way Jin
- M.I.N.D. Institute, Alzheimer's Disease Center, Department of Pathology and Laboratory Medicine, UCD, Davis, California, USA
| | - Huajun Jin
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Srikant Rangaraju
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Vellareddy Anantharam
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, UCD, Davis, California, USA
| | - Anumantha G Kanthasamy
- Parkinson Disorders Research Laboratory, Department of Biomedical Sciences, Iowa State University (ISU), Ames, Iowa, USA
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10
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Abstract
In the last 5 years inhibitors of the potassium channel KV1.3 have been shown to reduce neuroinflammation in rodent models of ischemic stroke, Alzheimer’s disease, Parkinson’s disease and traumatic brain injury. At the systemic level these beneficial actions are mediated by a reduction in microglia activation and a suppression of pro-inflammatory cytokine and nitric oxide production. However, the molecular mechanisms for the suppressive action of KV1.3 blockers on pro-inflammatory microglia functions was not known until our group recently demonstrated that KV1.3 channels not only regulate membrane potential, as would be expected of a voltage-gated potassium channel, but also play a crucial role in enabling microglia to resist depolarizations produced by the danger signal ATP thus regulating calcium influx through P2X4 receptors. We here review the role of KV1.3 in microglial signaling and show that, similarly to their role in T cells, KV1.3 channels also regulated store-operated calcium influx in microglia.
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Affiliation(s)
- Alla F Fomina
- Department of Physiology and Membrane Biology, University of California , Davis, CA, USA
| | - Hai M Nguyen
- Department of Pharmacology, University of California , Davis, CA, USA
| | - Heike Wulff
- Department of Pharmacology, University of California , Davis, CA, USA
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11
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Nguyen HM, di Lucente J, Chen YJ, Cui Y, Ibrahim RH, Pennington MW, Jin LW, Maezawa I, Wulff H. Biophysical basis for Kv1.3 regulation of membrane potential changes induced by P2X4-mediated calcium entry in microglia. Glia 2020; 68:2377-2394. [PMID: 32525239 PMCID: PMC7540709 DOI: 10.1002/glia.23847] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [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: 12/06/2019] [Revised: 04/17/2020] [Accepted: 05/07/2020] [Indexed: 12/02/2022]
Abstract
Microglia‐mediated inflammation exerts adverse effects in ischemic stroke and in neurodegenerative disorders such as Alzheimer's disease (AD). Expression of the voltage‐gated potassium channel Kv1.3 is required for microglia activation. Both genetic deletion and pharmacological inhibition of Kv1.3 are effective in reducing microglia activation and the associated inflammatory responses, as well as in improving neurological outcomes in animal models of AD and ischemic stroke. Here we sought to elucidate the molecular mechanisms underlying the therapeutic effects of Kv1.3 inhibition, which remain incompletely understood. Using a combination of whole‐cell voltage‐clamp electrophysiology and quantitative PCR (qPCR), we first characterized a stimulus‐dependent differential expression pattern for Kv1.3 and P2X4, a major ATP‐gated cationic channel, both in vitro and in vivo. We then demonstrated by whole‐cell current‐clamp experiments that Kv1.3 channels contribute not only to setting the resting membrane potential but also play an important role in counteracting excessive membrane potential changes evoked by depolarizing current injections. Similarly, the presence of Kv1.3 channels renders microglia more resistant to depolarization produced by ATP‐mediated P2X4 receptor activation. Inhibiting Kv1.3 channels with ShK‐223 completely nullified the ability of Kv1.3 to normalize membrane potential changes, resulting in excessive depolarization and reduced calcium transients through P2X4 receptors. Our report thus links Kv1.3 function to P2X4 receptor‐mediated signaling as one of the underlying mechanisms by which Kv1.3 blockade reduces microglia‐mediated inflammation. While we could confirm previously reported differences between males and females in microglial P2X4 expression, microglial Kv1.3 expression exhibited no gender differences in vitro or in vivo. Main Points The voltage‐gated K+ channel Kv1.3 regulates microglial membrane potential. Inhibition of Kv1.3 depolarizes microglia and reduces calcium entry mediated by P2X4 receptors by dissipating the electrochemical driving force for calcium.
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Affiliation(s)
- Hai M Nguyen
- Department of Pharmacology, University of California, Davis, California, USA
| | - Jacopo di Lucente
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California, USA
| | - Yi-Je Chen
- Department of Pharmacology, University of California, Davis, California, USA
| | - Yanjun Cui
- Department of Pharmacology, University of California, Davis, California, USA
| | - Rania H Ibrahim
- Department of Pharmacology, University of California, Davis, California, USA
| | | | - Lee-Way Jin
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California, USA
| | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California, USA
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California, USA
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12
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Ong ST, Bajaj S, Tanner MR, Chang SC, Krishnarjuna B, Ng XR, Morales RAV, Chen MW, Luo D, Patel D, Yasmin S, Ng JJH, Zhuang Z, Nguyen HM, El Sahili A, Lescar J, Patil R, Charman SA, Robins EG, Goggi JL, Tan PW, Sadasivam P, Ramasamy B, Hartimath SV, Dhawan V, Bednenko J, Colussi P, Wulff H, Pennington MW, Kuyucak S, Norton RS, Beeton C, Chandy KG. Modulation of Lymphocyte Potassium Channel K V1.3 by Membrane-Penetrating, Joint-Targeting Immunomodulatory Plant Defensin. ACS Pharmacol Transl Sci 2020; 3:720-736. [PMID: 32832873 DOI: 10.1021/acsptsci.0c00035] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Indexed: 12/23/2022]
Abstract
We describe a cysteine-rich, membrane-penetrating, joint-targeting, and remarkably stable peptide, EgK5, that modulates voltage-gated KV1.3 potassium channels in T lymphocytes by a distinctive mechanism. EgK5 enters plasma membranes and binds to KV1.3, causing current run-down by a phosphatidylinositol 4,5-bisphosphate-dependent mechanism. EgK5 exhibits selectivity for KV1.3 over other channels, receptors, transporters, and enzymes. EgK5 suppresses antigen-triggered proliferation of effector memory T cells, a subset enriched among pathogenic autoreactive T cells in autoimmune disease. PET-CT imaging with 18F-labeled EgK5 shows accumulation of the peptide in large and small joints of rodents. In keeping with its arthrotropism, EgK5 treats disease in a rat model of rheumatoid arthritis. It was also effective in treating disease in a rat model of atopic dermatitis. No signs of toxicity are observed at 10-100 times the in vivo dose. EgK5 shows promise for clinical development as a therapeutic for autoimmune diseases.
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Affiliation(s)
- Seow Theng Ong
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Saumya Bajaj
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Mark R Tanner
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States
| | - Shih Chieh Chang
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Xuan Rui Ng
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Rodrigo A V Morales
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Ming Wei Chen
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Dharmeshkumar Patel
- School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Sabina Yasmin
- School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Jeremy Jun Heng Ng
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Zhong Zhuang
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Hai M Nguyen
- Department of Pharmacology, University of California, Davis, California 95616, United States
| | - Abbas El Sahili
- School of Biological Sciences, Nanyang Institute of Structural Biology, Experimental Medicine building, Singapore 636921
| | - Julien Lescar
- School of Biological Sciences, Nanyang Institute of Structural Biology, Experimental Medicine building, Singapore 636921
| | - Rahul Patil
- Centre for Drug Candidate Optimisation, Monash University, Parkville, Victoria 3052, Australia
| | - Susan A Charman
- Centre for Drug Candidate Optimisation, Monash University, Parkville, Victoria 3052, Australia
| | - Edward G Robins
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667.,Singapore Bioimaging Consortium, NUS Clinical Imaging Research Centre (CIRC), Centre for Life Sciences, Singapore 117599
| | - Julian L Goggi
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Peng Wen Tan
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Pragalath Sadasivam
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Boominathan Ramasamy
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Siddana V Hartimath
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Vikas Dhawan
- Peptides International, Inc., Louisville, Kentucky 40269, United States.,AmbioPharm Inc., North Augusta, South Carolina 29842, United States
| | - Janna Bednenko
- TetraGenetics Inc, Arlington, Massachusetts 02474, United States
| | - Paul Colussi
- TetraGenetics Inc, Arlington, Massachusetts 02474, United States
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California 95616, United States
| | - Michael W Pennington
- Peptides International, Inc., Louisville, Kentucky 40269, United States.,AmbioPharm Inc., North Augusta, South Carolina 29842, United States
| | - Serdar Kuyucak
- School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia.,ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria 3052, Australia
| | - Christine Beeton
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States
| | - K George Chandy
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
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13
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Chen YJ, Nguyen HM, Cui Y, Wulff H. Kv1.3 Constitutes a Valid Target for Reducing Neuroinflammation in the Wake of Ischemic Stroke in Male, Female and Aged Mice. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.03005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Maezawa I, Nguyen HM, Di Lucente J, Jenkins DP, Singh V, Hilt S, Kim K, Rangaraju S, Levey AI, Wulff H, Jin LW. Kv1.3 inhibition as a potential microglia-targeted therapy for Alzheimer's disease: preclinical proof of concept. Brain 2019; 141:596-612. [PMID: 29272333 DOI: 10.1093/brain/awx346] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [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: 07/14/2017] [Accepted: 10/30/2017] [Indexed: 12/14/2022] Open
Abstract
Microglia significantly contribute to the pathophysiology of Alzheimer's disease but an effective microglia-targeted therapeutic approach is not yet available clinically. The potassium channels Kv1.3 and Kir2.1 play important roles in regulating immune cell functions and have been implicated by in vitro studies in the 'M1-like pro-inflammatory' or 'M2-like anti-inflammatory' state of microglia, respectively. We here found that amyloid-β oligomer-induced expression of Kv1.3 and Kir2.1 in cultured primary microglia. Likewise, ex vivo microglia acutely isolated from the Alzheimer's model 5xFAD mice co-expressed Kv1.3 and Kir2.1 as well as markers traditionally associated with M1 and M2 activation suggesting that amyloid-β oligomer induces a microglial activation state that is more complex than previously thought. Using the orally available, brain penetrant small molecule Kv1.3 blocker PAP-1 as a tool, we showed that pro-inflammatory and neurotoxic microglial responses induced by amyloid-β oligomer required Kv1.3 activity in vitro and in hippocampal slices. Since we further observed that Kv1.3 was highly expressed in microglia of transgenic Alzheimer's mouse models and human Alzheimer's disease brains, we hypothesized that pharmacological Kv1.3 inhibition could mitigate the pathology induced by amyloid-β aggregates. Indeed, treating APP/PS1 transgenic mice with a 5-month oral regimen of PAP-1, starting at 9 months of age, when the animals already manifest cognitive deficits and amyloid pathology, reduced neuroinflammation, decreased cerebral amyloid load, enhanced hippocampal neuronal plasticity, and improved behavioural deficits. The observed decrease in cerebral amyloid deposition was consistent with the in vitro finding that PAP-1 enhanced amyloid-β uptake by microglia. Collectively, these results provide proof-of-concept data to advance Kv1.3 blockers to Alzheimer's disease clinical trials.
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Affiliation(s)
- Izumi Maezawa
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, 2805 50th Street, Sacramento, CA 95817, USA
| | - Hai M Nguyen
- Department of Pharmacology, University of California Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
| | - Jacopo Di Lucente
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, 2805 50th Street, Sacramento, CA 95817, USA
| | - David Paul Jenkins
- Department of Pharmacology, University of California Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
| | - Vikrant Singh
- Department of Pharmacology, University of California Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
| | - Silvia Hilt
- Department of Biochemistry and Molecular Medicine, University of California Davis, 2700 Stockton Blvd, Sacramento, CA 95817, USA
| | - Kyoungmi Kim
- Department of Public Health Sciences, University of California Davis, One Shields Avenue, Med Sci 1-C, Davis, CA 95616, USA
| | - Srikant Rangaraju
- Department of Neurology and Alzheimer's Disease Research Center, Emory University, 201 Dowman Drive, Atlanta, GA 30322, USA
| | - Allan I Levey
- Department of Neurology and Alzheimer's Disease Research Center, Emory University, 201 Dowman Drive, Atlanta, GA 30322, USA
| | - Heike Wulff
- Department of Pharmacology, University of California Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
| | - Lee-Way Jin
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, 2805 50th Street, Sacramento, CA 95817, USA.,Alzheimer's Disease Center, University of California Davis Medical Center, 4860 Y Street, Suite 3900, Sacramento, CA 95817, USA
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15
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Jin LW, Lucente JD, Nguyen HM, Singh V, Singh L, Chavez M, Bushong T, Wulff H, Maezawa I. Repurposing the KCa3.1 inhibitor senicapoc for Alzheimer's disease. Ann Clin Transl Neurol 2019; 6:723-738. [PMID: 31019997 PMCID: PMC6469250 DOI: 10.1002/acn3.754] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/06/2019] [Accepted: 02/10/2019] [Indexed: 01/01/2023] Open
Abstract
Objective Microglia play a pivotal role in the initiation and progression of Alzheimer's disease (AD). We here tested the therapeutic hypothesis that the Ca2+‐activated potassium channel KCa3.1 constitutes a potential target for treating AD by reducing neuroinflammation. Methods To determine if KCa3.1 is relevant to AD, we tested if treating cultured microglia or hippocampal slices with Aβ oligomer (AβO) activated KCa3.1 in microglia, and if microglial KCa3.1 was upregulated in 5xFAD mice and in human AD brains. The expression/activity of KCa3.1 was examined by qPCR, Western blotting, immunohistochemistry, and whole‐cell patch‐clamp. To investigate the role of KCa3.1 in AD pathology, we resynthesized senicapoc, a clinically tested KCa3.1 blocker, and determined its pharmacokinetic properties and its effect on microglial activation, Aβ deposition and hippocampal long‐term potentiation (hLTP) in 5xFAD mice. Results We found markedly enhanced microglial KCa3.1 expression/activity in brains of both 5xFAD mice and AD patients. In hippocampal slices, microglial KCa3.1 expression/activity was increased by AβO treatment, and its inhibition diminished the proinflammatory and hLTP‐impairing activities of AβO. Senicapoc exhibited excellent brain penetrance and oral availability, and in 5xFAD mice, reduced neuroinflammation, decreased cerebral amyloid load, and enhanced hippocampal neuronal plasticity. Interpretation Our results prompt us to propose repurposing senicapoc for AD clinical trials, as senicapoc has excellent pharmacological properties and was safe and well‐tolerated in a prior phase‐3 clinical trial for sickle cell anemia. Such repurposing has the potential to expedite the urgently needed new drug discovery for AD.
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Affiliation(s)
- Lee-Way Jin
- Department of Pathology and Laboratory Medicine University of California Davis Medical Center Sacramento California
| | - Jacopo Di Lucente
- Department of Pathology and Laboratory Medicine University of California Davis Medical Center Sacramento California
| | - Hai M Nguyen
- Department of Pharmacology University of California Davis Davis California
| | - Vikrant Singh
- Department of Pharmacology University of California Davis Davis California
| | - Latika Singh
- Department of Pharmacology University of California Davis Davis California
| | - Monique Chavez
- Department of Pathology and Laboratory Medicine University of California Davis Medical Center Sacramento California
| | - Trevor Bushong
- Department of Pathology and Laboratory Medicine University of California Davis Medical Center Sacramento California
| | - Heike Wulff
- Department of Pharmacology University of California Davis Davis California
| | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine University of California Davis Medical Center Sacramento California
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16
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Ma P, Kang EL, Braverman AJ, Nguyen HM. Spatial Statistical Downscaling for Constructing High-Resolution Nature Runs in Global Observing System Simulation Experiments. Technometrics 2019. [DOI: 10.1080/00401706.2018.1524791] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Pulong Ma
- The Statistical and Applied Mathematical Sciences Institute and Duke University, Durham, NC
| | - Emily L. Kang
- Department of Mathematical Sciences, University of Cincinnati, Cincinnati, OH
| | - Amy J. Braverman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA
| | - Hai M. Nguyen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA
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17
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Theng Ong S, Thomas G, Kannan S, Her Z, Rui Ng X, Chew X, Nguyen HM, Wulff H, Verma C, Chen Q, Ahmed M, Chandy KG. Novel Inhibitors of the Calcium-Activated K+ Channel KCa3.1 to Treat Non-Alcoholic Fatty Liver Disease and Liver Fibrosis. Biophys J 2019. [DOI: 10.1016/j.bpj.2018.11.1362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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18
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Wulff H, Di Lucente J, Nguyen HM, Singh V, Jin LW, Maezawa I. Repursposing the Kca3.1 Blocker Senicapoc as a Microglia-Targeted Therapeutic for Alzheimer's Disease. Biophys J 2019. [DOI: 10.1016/j.bpj.2018.11.1345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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19
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Abstract
As their name implies, cation channels allow the regulated flow of cations such as sodium, potassium, calcium, and magnesium across cellular and intracellular membranes. Cation channels have long been known for their fundamental roles in controlling membrane potential and excitability in neurons and muscle. In this review, we provide an update on the recent advances in our understanding of the structure–function relationship and the physiological and pathophysiological role of cation channels. The most exciting developments in the last two years, in our opinion, have been the insights that cryoelectron microscopy has provided into the inner life and the gating of not only voltage-gated channels but also mechanosensitive and calcium- or sodium-activated channels. The mechanosensitive Piezo channels especially have delighted the field not only with a fascinating new type of structure but with important roles in blood pressure regulation and lung function.
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Affiliation(s)
- Brandon M Brown
- Department of Pharmacology, School of Medicine, University of California, Davis, USA
| | - Hai M Nguyen
- Department of Pharmacology, School of Medicine, University of California, Davis, USA
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, USA
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20
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Di Lucente J, Nguyen HM, Wulff H, Jin LW, Maezawa I. The voltage-gated potassium channel Kv1.3 is required for microglial pro-inflammatory activation in vivo. Glia 2018; 66:1881-1895. [PMID: 30043400 DOI: 10.1002/glia.23457] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [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: 10/10/2017] [Revised: 04/26/2018] [Accepted: 05/02/2018] [Indexed: 11/09/2022]
Abstract
Microglia show a rich repertoire of activation patterns regulated by a complex ensemble of surface ion channels, receptors, and transporters. We and others have investigated whether microglia vary their K+ channel expression as a means to achieve functional diversity. However, most of the prior studies were conducted using in vitro models such as BV2 cells, primary microglia, or brain slices in culture, which may not accurately reflect microglia physiology in adult individuals. Here we employed an in vivo mouse model of selective innate immune activation by intracerebroventricular injection of lipopolysaccharides (ICV-LPS) to determine the role of the voltage-gated Kv1.3 channel in LPS-induced M1-like microglial activation. Using microglia acutely isolated from adult brains, we detected Kv1.3 and Kir2.1 currents, and found that ICV-LPS increased the current density and RNA expression of Kv1.3 but did not affect those of Kir2.1. Genetic knockout of Kv1.3 abolished LPS-induced microglial activation exemplified by Iba-1 immunoreactivity and expression of pro-inflammatory mediators such as IL-1β, TNF-α, IL-6, and iNOS. Moreover, Kv1.3 knockout mitigated the LPS-induced impairment of hippocampal long-term potentiation (hLTP), suggesting that Kv1.3 activity regulates pro-inflammatory microglial neurotoxicity. Pharmacological intervention using PAP-1, a small molecule that selectively blocks homotetrameric Kv1.3 channels, achieved anti-inflammatory and hLTP-recovery effects similar to Kv1.3 knockout. We conclude that Kv1.3 is required for microglial M1-like pro-inflammatory activation in vivo. A significant implication of our in vivo data is that Kv1.3 blockers could be therapeutic candidates for neurological diseases where microglia-mediated neurotoxicity is implicated in the pathogenesis.
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Affiliation(s)
- Jacopo Di Lucente
- From the Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California
| | - Hai M Nguyen
- Department of Pharmacology, University of California, Davis, California
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California
| | - Lee-Way Jin
- From the Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California
| | - Izumi Maezawa
- From the Department of Pathology and Laboratory Medicine and M.I.N.D. Institute, University of California Davis Medical Center, Sacramento, California
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21
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Bednenko J, Harriman R, Mariën L, Nguyen HM, Agrawal A, Papoyan A, Bisharyan Y, Cardarelli J, Cassidy-Hanley D, Clark T, Pedersen D, Abdiche Y, Harriman W, van der Woning B, de Haard H, Collarini E, Wulff H, Colussi P. A multiplatform strategy for the discovery of conventional monoclonal antibodies that inhibit the voltage-gated potassium channel Kv1.3. MAbs 2018; 10:636-650. [PMID: 29494279 PMCID: PMC5973702 DOI: 10.1080/19420862.2018.1445451] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [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] [Indexed: 11/19/2022] Open
Abstract
Identifying monoclonal antibodies that block human voltage-gated ion channels (VGICs) is a challenging endeavor exacerbated by difficulties in producing recombinant ion channel proteins in amounts that support drug discovery programs. We have developed a general strategy to address this challenge by combining high-level expression of recombinant VGICs in Tetrahymena thermophila with immunization of phylogenetically diverse species and unique screening tools that allow deep-mining for antibodies that could potentially bind functionally important regions of the protein. Using this approach, we targeted human Kv1.3, a voltage-gated potassium channel widely recognized as a therapeutic target for the treatment of a variety of T-cell mediated autoimmune diseases. Recombinant Kv1.3 was used to generate and recover 69 full-length anti-Kv1.3 mAbs from immunized chickens and llamas, of which 10 were able to inhibit Kv1.3 current. Select antibodies were shown to be potent (IC50<10 nM) and specific for Kv1.3 over related Kv1 family members, hERG and hNav1.5.
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Affiliation(s)
| | - Rian Harriman
- b Department of Immunology , Crystal Bioscience , Emeryville , California , USA
| | | | - Hai M Nguyen
- d Department of Pharmacology , University of California , Davis , California , USA
| | - Alka Agrawal
- a TetraGenetics Inc , Arlington , Massachusetts , USA
| | - Ashot Papoyan
- a TetraGenetics Inc , Arlington , Massachusetts , USA
| | | | | | - Donna Cassidy-Hanley
- e Department of Immunology and Microbiology , Cornell University , Ithaca , New York , USA
| | - Ted Clark
- a TetraGenetics Inc , Arlington , Massachusetts , USA.,e Department of Immunology and Microbiology , Cornell University , Ithaca , New York , USA
| | | | | | | | | | | | | | - Heike Wulff
- d Department of Pharmacology , University of California , Davis , California , USA
| | - Paul Colussi
- a TetraGenetics Inc , Arlington , Massachusetts , USA
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22
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Wulff H, Nguyen HM, Brown BM, Shim H, Yarov‐Yarovoy V. Structure Assisted Design of Small Molecule KCa Channel Modulators. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.556.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Heike Wulff
- PharmacologyUniversity of CaliforniaDavisDavisCA
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Wulff H, Chen YJ, Nguyen HM, Maezawa I, Jin LW. Inhibition of the Potassium Channel Kv1.3 Reduces Infarction and Inflammation in Ischemic Stroke. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.1133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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24
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Bednenko J, Harriman R, Mariën L, Nguyen HM, Agrawal A, Papoyan A, Bisharyan Y, Cardarelli J, Clark T, Cassidy-Hanley D, der Woning BV, de Haard H, Collarini E, Wulff H, Colussi P. Development of KV1.3-Blocking Monoclonal Antibodies using Tetrahymena thermophila. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.1749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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25
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Schwandner FM, Gunson MR, Miller CE, Carn SA, Eldering A, Krings T, Verhulst KR, Schimel DS, Nguyen HM, Crisp D, O'Dell CW, Osterman GB, Iraci LT, Podolske JR. Spaceborne detection of localized carbon dioxide sources. Science 2018; 358:358/6360/eaam5782. [PMID: 29026015 DOI: 10.1126/science.aam5782] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 07/06/2017] [Indexed: 11/03/2022]
Abstract
Spaceborne measurements by NASA's Orbiting Carbon Observatory-2 (OCO-2) at the kilometer scale reveal distinct structures of atmospheric carbon dioxide (CO2) caused by known anthropogenic and natural point sources. OCO-2 transects across the Los Angeles megacity (USA) show that anthropogenic CO2 enhancements peak over the urban core and decrease through suburban areas to rural background values more than ~100 kilometers away, varying seasonally from ~4.4 to 6.1 parts per million. A transect passing directly downwind of the persistent isolated natural CO2 plume from Yasur volcano (Vanuatu) shows a narrow filament of enhanced CO2 values (~3.4 parts per million), consistent with a CO2 point source emitting 41.6 kilotons per day. These examples highlight the potential of the OCO-2 sensor, with its unprecedented resolution and sensitivity, to detect localized natural and anthropogenic CO2 sources.
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Affiliation(s)
- Florian M Schwandner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. .,Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Michael R Gunson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Charles E Miller
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Simon A Carn
- Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, MI 49931, USA
| | - Annmarie Eldering
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Thomas Krings
- Institute of Environmental Physics, University of Bremen, 28334 Bremen, Germany
| | - Kristal R Verhulst
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.,Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - David S Schimel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Hai M Nguyen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - David Crisp
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Christopher W O'Dell
- Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523, USA
| | - Gregory B Osterman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Laura T Iraci
- NASA Ames Research Center, Moffett Field, CA 94035, USA
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Chen YJ, Nguyen HM, Maezawa I, Jin LW, Wulff H. Inhibition of the potassium channel Kv1.3 reduces infarction and inflammation in ischemic stroke. Ann Clin Transl Neurol 2017; 5:147-161. [PMID: 29468176 PMCID: PMC5817832 DOI: 10.1002/acn3.513] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/10/2017] [Accepted: 11/20/2017] [Indexed: 12/26/2022] Open
Abstract
Objective Inhibitors of the voltage‐gated K+ channel Kv1.3 are currently in development as immunomodulators for the treatment of autoimmune diseases. As Kv1.3 is also expressed on microglia and has been shown to be specifically up‐regulated on “M1‐like” microglia, we here tested the therapeutic hypothesis that the brain‐penetrant small‐molecule Kv1.3‐inhibitor PAP‐1 reduces secondary inflammatory damage after ischemia/reperfusion. Methods We studied microglial Kv1.3 expression using electrophysiology and immunohistochemistry, and evaluated PAP‐1 in hypoxia‐exposed organotypic hippocampal slices and in middle cerebral artery occlusion (MCAO) with 8 days of reperfusion in both adult male C57BL/6J mice (60 min MCAO) and adult male Wistar rats (90 min MCAO). In both models, PAP‐1 administration was started 12 h after reperfusion. Results We observed Kv1.3 staining on activated microglia in ischemic infarcts in mice, rats, and humans and found higher Kv1.3 current densities in acutely isolated microglia from the infarcted hemisphere than in microglia isolated from the contralateral hemisphere of MCAO mice. PAP‐1 reduced microglia activation and increased neuronal survival in hypoxia‐exposed hippocampal slices as effectively as minocycline. In mouse MCAO, PAP‐1 dose‐dependently reduced infarct area, improved neurological deficit score, and reduced brain levels of IL‐1β and IFN‐γ without affecting IL‐10 and brain‐derived nerve growth factor (BDNF) levels or inhibiting ongoing phagocytosis. The beneficial effects on infarct area and neurological deficit score were reproduced in rats providing confirmation in a second species. Interpretation Our findings suggest that Kv1.3 constitutes a promising therapeutic target for preferentially inhibiting “M1‐like” inflammatory microglia/macrophage functions in ischemic stroke.
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Affiliation(s)
- Yi-Je Chen
- Department of Pharmacology University of California Davis 95616 California
| | - Hai M Nguyen
- Department of Pharmacology University of California Davis 95616 California
| | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine University of California Davis, Sacramento 95817 California.,M.I.N.D. Institute University of California Davis 95817 California
| | - Lee-Way Jin
- Department of Pathology and Laboratory Medicine University of California Davis, Sacramento 95817 California.,M.I.N.D. Institute University of California Davis 95817 California
| | - Heike Wulff
- Department of Pharmacology University of California Davis 95616 California
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27
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Barnych B, Vasylieva N, Joseph T, Hulsizer S, Nguyen HM, Cajka T, Pessah I, Wulff H, Gee SJ, Hammock BD. Development of Tetramethylenedisulfotetramine (TETS) Hapten Library: Synthesis, Electrophysiological Studies, and Immune Response in Rabbits. Chemistry 2017; 23:8466-8472. [PMID: 28411375 PMCID: PMC5808876 DOI: 10.1002/chem.201700783] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [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: 02/17/2017] [Revised: 04/08/2017] [Indexed: 11/06/2022]
Abstract
There is a need for fast detection methods for the banned rodenticide tetramethylenedisulfotetramine (TETS), a highly potent blocker of the γ-aminobutyric acid (GABAA ) receptors. General synthetic approach toward two groups of analogues was developed. Screening of the resulting library of compounds by FLIPR or whole-cell voltage-clamp revealed that, despite the structural differences, some of the TETS analogues retained GABAA receptor inhibition; however, their potency was an order of magnitude lower. Antibodies raised in rabbits against some of the TETS analogues conjugated to protein recognized free TETS and will be used for the development of an immunoassay for TETS.
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Affiliation(s)
- Bogdan Barnych
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, 95616, United States
| | - Natalia Vasylieva
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, 95616, United States
| | - Tom Joseph
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, 95616, United States
| | - Susan Hulsizer
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California, 95616, United States
| | - Hai M Nguyen
- Department of Pharmacology, School of Medicine, University of California Davis, Davis, California, 95616, United States
| | - Tomas Cajka
- UC Davis Genome Center-Metabolomics, University of California Davis, Davis, California, 95616, United States
| | - Isaac Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California, 95616, United States
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California Davis, Davis, California, 95616, United States
| | - Shirley J Gee
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, 95616, United States
| | - Bruce D Hammock
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, 95616, United States
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Vasylieva N, Barnych B, Wan D, El-Sheikh ESA, Nguyen HM, Wulff H, McMahen R, Strynar M, Gee SJ, Hammock BD. Hydroxy-fipronil is a new urinary biomarker of exposure to fipronil. Environ Int 2017; 103:91-98. [PMID: 28343720 PMCID: PMC5432128 DOI: 10.1016/j.envint.2017.03.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 06/01/2023]
Abstract
Occupational medical surveillance is highly desirable in manufacturing facilities where exposure to chemicals is significant. The insecticide fipronil is generally considered safe for humans but with increasing use, exposure to fipronil is of concern. Identification of urinary metabolites of fipronil may allow development of affordable, cheap and rapid procedures for human exposure evaluation. In this study we developed a fast and easy approach for synthesis of hydroxy-fipronil, a potential urinary metabolite of fipronil. This standard was used to develop a sensitive analytical LC-MS/MS method with a limit of quantification (LOQ) of 0.4ng/mL. Fipronil sulfone, a known metabolite, and hydroxy-fipronil were quantified in urine samples from rats treated with a fipronil containing diet. Fipronil sulfone concentration centered around 20ng/mL, while the concentration of hydroxy-fipronil was dose-dependent ranging in 10-10,000ng/mL and thus being a more sensitive marker of fipronil exposure. A fipronil immunoassay with cross-reactivity to hydroxy-fipronil showed a good correlation in signal intensity with LC-MS data. It was also used to demonstrate the applicability of the method for sample screening in the evaluation of exposure levels.
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Affiliation(s)
- Natalia Vasylieva
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, United States
| | - Bogdan Barnych
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, United States
| | - Debin Wan
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, United States
| | | | - Hai M Nguyen
- Department of Pharmacology, University of California Davis, Davis, CA 95616, United States
| | - Heike Wulff
- Department of Pharmacology, University of California Davis, Davis, CA 95616, United States
| | - Rebecca McMahen
- United States Environmental Protection Agency, National Exposure Research Laboratory, Research Triangle Park, NC, United States
| | - Mark Strynar
- United States Environmental Protection Agency, National Exposure Research Laboratory, Research Triangle Park, NC, United States
| | - Shirley J Gee
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, United States
| | - Bruce D Hammock
- Department of Entomology and Nematology, and UCD Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, United States.
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Nguyen HM, Blomster LV, Christophersen P, Wulff H. Potassium channel expression and function in microglia: Plasticity and possible species variations. Channels (Austin) 2017; 11:305-315. [PMID: 28277939 DOI: 10.1080/19336950.2017.1300738] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [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: 12/31/2022] Open
Abstract
Potassium channels play important roles in microglia functions and thus constitute potential targets for the treatment of neurodegenerative diseases like Alzheimer, Parkinson and stroke. However, uncertainty still prevails as to which potassium channels are expressed and at what levels in different species, how the expression pattern changes upon activation with M1 or M2 polarizing stimuli compared with more complex exposure paradigms, and - most importantly - how these findings relate to the in vivo situation. In this mini-review we discuss the functional potassium channel expression pattern in cultured neonatal mouse microglia in the light of data obtained previously from animal disease models and immunohistochemical studies and compare it with a recent study of adult human microglia isolated from epilepsy patients. Overall, microglial potassium channel expression is very plastic and possibly shows species differences and therefore should be studied carefully in each disease setting and respective animal models.
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Affiliation(s)
- Hai M Nguyen
- a Department of Pharmacology , University of California , Davis, Davis , CA , USA
| | | | | | - Heike Wulff
- a Department of Pharmacology , University of California , Davis, Davis , CA , USA
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30
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Shim H, Brown B, Nguyen HM, Yarov-Yarovoy V, Wulff H. Rational Design of K Ca 2 Channel Activators. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.2567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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31
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Wulff H, Di Lucente J, Nguyen HM, Singh V, Jin LW, Maezawa I. Kv1.3 Inhibition Reduces Amyloid-Beta Induced Microglial Neurotoxicity. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.2961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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32
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Nguyen HM, Grössinger EM, Horiuchi M, Davis KW, Jin LW, Maezawa I, Wulff H. Differential K + Channels Expression in “Classically” and “Alternatively” Activated Microglia. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.1805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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33
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Pressly B, Nguyen HM, Wulff H. Subtype Selectivity of Tets on GABA-A Receptors. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.2572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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34
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Nguyen HM, Singh V, Pressly B, Jenkins DP, Wulff H, Yarov-Yarovoy V. Structural Insights into the Atomistic Mechanisms of Action of Small Molecule Inhibitors Targeting the KCa3.1 Channel Pore. Mol Pharmacol 2017; 91:392-402. [PMID: 28126850 DOI: 10.1124/mol.116.108068] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 01/19/2017] [Indexed: 12/13/2022] Open
Abstract
The intermediate-conductance Ca2+-activated K+ channel (KCa3.1) constitutes an attractive pharmacological target for immunosuppression, fibroproliferative disorders, atherosclerosis, and stroke. However, there currently is no available crystal structure of this medically relevant channel that could be used for structure-assisted drug design. Using the Rosetta molecular modeling suite we generated a molecular model of the KCa3.1 pore and tested the model by first confirming previously mapped binding sites and visualizing the mechanism of TRAM-34 (1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole), senicapoc (2,2-bis-(4-fluorophenyl)-2-phenylacetamide), and NS6180 (4-[[3-(trifluoromethyl)phenyl]methyl]-2H-1,4-benzothiazin-3(4H)-one) inhibition at the atomistic level. All three compounds block ion conduction directly by fully or partially occupying the site that would normally be occupied by K+ before it enters the selectivity filter. We then challenged the model to predict the receptor sites and mechanisms of action of the dihydropyridine nifedipine and an isosteric 4-phenyl-pyran. Rosetta predicted receptor sites for nifedipine in the fenestration region and for the 4-phenyl-pyran in the pore lumen, which could both be confirmed by site-directed mutagenesis and electrophysiology. While nifedipine is thus not a pore blocker and might be stabilizing the channel in a nonconducting conformation or interfere with gating, the 4-phenyl-pyran was found to be a classical pore blocker that directly inhibits ion conduction similar to the triarylmethanes TRAM-34 and senicapoc. The Rosetta KCa3.1 pore model explains the mechanism of action of several KCa3.1 blockers at the molecular level and could be used for structure-assisted drug design.
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Affiliation(s)
- Hai M Nguyen
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
| | - Vikrant Singh
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
| | - Brandon Pressly
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
| | - David Paul Jenkins
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
| | - Heike Wulff
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
| | - Vladimir Yarov-Yarovoy
- Department of Pharmacology (H.M.N, V.S., B.P., D.P.J., H.W.) and Department of Physiology and Membrane Biology (V. Y.-Y.), School of Medicine, University of California at Davis, Davis, California
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Chen YJ, Nguyen HM, Maezawa I, Grössinger EM, Garing AL, Köhler R, Jin LW, Wulff H. The potassium channel KCa3.1 constitutes a pharmacological target for neuroinflammation associated with ischemia/reperfusion stroke. J Cereb Blood Flow Metab 2016; 36:2146-2161. [PMID: 26661208 PMCID: PMC5363659 DOI: 10.1177/0271678x15611434] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 08/25/2015] [Accepted: 09/13/2015] [Indexed: 11/16/2022]
Abstract
Activated microglia/macrophages significantly contribute to the secondary inflammatory damage in ischemic stroke. Cultured neonatal microglia express the K+ channels Kv1.3 and KCa3.1, both of which have been reported to be involved in microglia-mediated neuronal killing, oxidative burst and cytokine production. However, it is questionable whether neonatal cultures accurately reflect the K+ channel expression of activated microglia in the adult brain. We here subjected mice to middle cerebral artery occlusion with eight days of reperfusion and patch-clamped acutely isolated microglia/macrophages. Microglia from the infarcted area exhibited higher densities of K+ currents with the biophysical and pharmacological properties of Kv1.3, KCa3.1 and Kir2.1 than microglia from non-infarcted control brains. Similarly, immunohistochemistry on human infarcts showed strong Kv1.3 and KCa3.1 immunoreactivity on activated microglia/macrophages. We next investigated the effect of genetic deletion and pharmacological blockade of KCa3.1 in reversible middle cerebral artery occlusion. KCa3.1-/- mice and wild-type mice treated with the KCa3.1 blocker TRAM-34 exhibited significantly smaller infarct areas on day-8 after middle cerebral artery occlusion and improved neurological deficit. Both manipulations reduced microglia/macrophage activation and brain cytokine levels. Our findings suggest KCa3.1 as a pharmacological target for ischemic stroke. Of potential, clinical relevance is that KCa3.1 blockade is still effective when initiated 12 h after the insult.
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Affiliation(s)
- Yi-Je Chen
- Department of Pharmacology, University of California, Davis, CA, USA.,Microsurgery Core, University of California, Davis, CA, USA
| | - Hai M Nguyen
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine, University of California, Davis, Sacramento, CA, USA.,M.I.N.D. Institute, University of California, Davis, Sacramento, CA, USA
| | - Eva M Grössinger
- Department of Pharmacology, University of California, Davis, CA, USA
| | - April L Garing
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Ralf Köhler
- Aragon Institute of Health Sciences/IIS and ARAID, Zaragoza, Spain
| | - Lee-Way Jin
- Department of Pathology and Laboratory Medicine, University of California, Davis, Sacramento, CA, USA.,M.I.N.D. Institute, University of California, Davis, Sacramento, CA, USA
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, CA, USA
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36
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Nguyen HM, Grössinger EM, Horiuchi M, Davis KW, Jin LW, Maezawa I, Wulff H. Differential Kv1.3, KCa3.1, and Kir2.1 expression in "classically" and "alternatively" activated microglia. Glia 2016; 65:106-121. [PMID: 27696527 PMCID: PMC5113690 DOI: 10.1002/glia.23078] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [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: 03/10/2016] [Accepted: 09/15/2016] [Indexed: 11/10/2022]
Abstract
Microglia are highly plastic cells that can assume different phenotypes in response to microenvironmental signals. Lipopolysaccharide (LPS) and interferon-γ (IFN-γ) promote differentiation into classically activated M1-like microglia, which produce high levels of pro-inflammatory cytokines and nitric oxide and are thought to contribute to neurological damage in ischemic stroke and Alzheimer's disease. IL-4 in contrast induces a phenotype associated with anti-inflammatory effects and tissue repair. We here investigated whether these microglia subsets vary in their K+ channel expression by differentiating neonatal mouse microglia into M(LPS) and M(IL-4) microglia and studying their K+ channel expression by whole-cell patch-clamp, quantitative PCR and immunohistochemistry. We identified three major types of K+ channels based on their biophysical and pharmacological fingerprints: a use-dependent, outwardly rectifying current sensitive to the KV 1.3 blockers PAP-1 and ShK-186, an inwardly rectifying Ba2+ -sensitive Kir 2.1 current, and a Ca2+ -activated, TRAM-34-sensitive KCa 3.1 current. Both KV 1.3 and KCa 3.1 blockers inhibited pro-inflammatory cytokine production and iNOS and COX2 expression demonstrating that KV 1.3 and KCa 3.1 play important roles in microglia activation. Following differentiation with LPS or a combination of LPS and IFN-γ microglia exhibited high KV 1.3 current densities (∼50 pA/pF at 40 mV) and virtually no KCa 3.1 and Kir currents, while microglia differentiated with IL-4 exhibited large Kir 2.1 currents (∼ 10 pA/pF at -120 mV). KCa 3.1 currents were generally low but moderately increased following stimulation with IFN-γ or ATP (∼10 pS/pF). This differential K+ channel expression pattern suggests that KV 1.3 and KCa 3.1 inhibitors could be used to inhibit detrimental neuroinflammatory microglia functions. GLIA 2016;65:106-121.
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Affiliation(s)
- Hai M Nguyen
- Department of Pharmacology, University of California, Davis, California
| | - Eva M Grössinger
- Department of Pharmacology, University of California, Davis, California
| | - Makoto Horiuchi
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, Sacramento, California.,M.I.N.D. Institute, University of California Davis Medical Center, Davis, Sacramento, California
| | - Kyle W Davis
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, Sacramento, California
| | - Lee-Way Jin
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, Sacramento, California.,M.I.N.D. Institute, University of California Davis Medical Center, Davis, Sacramento, California
| | - Izumi Maezawa
- Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, Sacramento, California.,M.I.N.D. Institute, University of California Davis Medical Center, Davis, Sacramento, California
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California
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Légeret B, Schulz-Raffelt M, Nguyen HM, Auroy P, Beisson F, Peltier G, Blanc G, Li-Beisson Y. Lipidomic and transcriptomic analyses of Chlamydomonas reinhardtii under heat stress unveil a direct route for the conversion of membrane lipids into storage lipids. Plant Cell Environ 2016; 39:834-47. [PMID: 26477535 DOI: 10.1111/pce.12656] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/01/2015] [Accepted: 10/06/2015] [Indexed: 05/18/2023]
Abstract
Studying how photosynthetic cells modify membrane lipids in response to heat stress is important to understand how plants and microalgae adapt to daily fluctuations in temperature and to investigate new lipid pathways. Here, we investigate changes occurring in lipid molecular species and lipid metabolism genes during early response to heat stress in the model photosynthetic microorganism Chlamydomonas reinhardtii. Lipid molecular species analyses revealed that, after 60 min at 42 °C, a strong decrease in specific polyunsaturated membrane lipids was observed together with an increase in polyunsaturated triacylglycerols (TAGs) and diacylglycerols (DAGs). The fact that decrease in the major chloroplastic monogalactosyldiacylglycerol sn1-18:3/sn2-16:4 was mirrored by an accumulation of DAG sn1-18:3/sn2-16:4 and TAG sn1-18:3/sn2-16:4/sn3-18:3 indicated that newly accumulated TAGs were formed via direct conversion of monogalactosyldiacylglycerols to DAGs then TAGs. Lipidomic analyses showed that the third fatty acid of a TAG likely originated from a phosphatidylethanolamine or a diacylglyceryl-O-4'-(N,N,N,-trimethyl)-homoserine betaine lipid species. Candidate genes for this TAG synthesis pathway were provided through comparative transcriptomic analysis and included a phospholipase A2 homolog and the DAG acyltransferase DGTT1. This study gives insights into the molecular events underlying changes in membrane lipids during heat stress and reveals an alternative route for TAG synthesis.
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Affiliation(s)
- B Légeret
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - M Schulz-Raffelt
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - H M Nguyen
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - P Auroy
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - F Beisson
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - G Peltier
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
| | - G Blanc
- Laboratoire Information Génomique & Structurale, UMR7256 (IMM FR3479) CNRS Aix-Marseille Université, Marseille, France
| | - Y Li-Beisson
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Environnementale et Biotechnologie, CEA Cadarache, Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique, UMR7265, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, UMR7265, Marseille, France
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Nguyen HM, Singh L, Wulff H, Yarov-Yarovoy V. Validation of KCa3.1 Channel Small Molecules Interaction Sites Predicted by Rosetta. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.2405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Chen YJ, Nguyen HM, Maezawa I, Jin LW, Wulff H. The Voltage-Gated Potassium Channel Kv1.3 as a Target for Inhibiting Detrimental M1 Microglia Functions. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.2821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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40
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Nguyen HM, Wulff H, Yarov-Yarovoy V. Validation of KCa3.1 Channel Nifedipine Interaction Site Predicted by Rosetta Modeling Method. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.3181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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41
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Sy BT, Nguyen HM, Toan NL, Song LH, Tong HV, Wolboldt C, Binh VQ, Kremsner PG, Velavan TP, Bock CT. Identification of a natural intergenotypic recombinant hepatitis delta virus genotype 1 and 2 in Vietnamese HBsAg-positive patients. J Viral Hepat 2015; 22:55-63. [PMID: 24548489 DOI: 10.1111/jvh.12228] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/02/2014] [Indexed: 12/18/2022]
Abstract
Hepatitis D virus (HDV) infection is acquired as a co- /superinfection of Hepatitis B virus (HBV) and can modulate the pathophysiology of chronic hepatitis B and related liver diseases including hepatocellular carcinoma. Among the eight distinct HDV genotypes reported, relatively few studies have attempted to investigate the prevalence of HDV mixed genotypes and RNA recombination of HDV. With a recorded prevalence of 10-20% HBV infection in Vietnam, this study investigated the HDV variability, HDV genotypes and HDV recombination among twenty-one HDV isolates in Vietnamese HBsAg-positive patients. HDV subgenomic and full-length genome sequences were obtained using newly established HDV-specific RT-PCR techniques. The nucleotide homology was observed from 74.6% to 99.4% among the investigated full-length genome of the HDV isolates. We observed HDV genotype 1 and HDV genotype 2 in the investigated Vietnamese patients. Although no HDV genotype mixtures were observed, we report here a newly identified recombinant of HDV genotypes (HDV 1 and HDV 2). The identified recombinant HDV isolate C03 revealed sequence homology to both HDV genotype 1 (nt1 to nt907) and HDV genotype 2 (nt908 to nt1675; HDAg coding region) with a breakpoint at nt908. Our findings demonstrate the prevalence of intergenotypic recombination between HDV genotypes 1 and 2 in a Vietnamese HBsAg-positive patient. Extended investigation on the distribution and prevalence of HDV, HDV mixed genotypes and recombinant HDV genotypes in a larger Vietnamese population offers vital insights into understanding of the micro-epidemiology of HDV and subsequent pathophysiology in chronic HBV- /HDV-related liver diseases.
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Affiliation(s)
- B T Sy
- Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany; Vietnam Military Medical University, Ha Noi, Viet Nam
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Coleman N, Nguyen HM, Cao Z, Brown BM, Jenkins DP, Zolkowska D, Chen YJ, Tanaka BS, Goldin AL, Rogawski MA, Pessah IN, Wulff H. The riluzole derivative 2-amino-6-trifluoromethylthio-benzothiazole (SKA-19), a mixed KCa2 activator and NaV blocker, is a potent novel anticonvulsant. Neurotherapeutics 2015; 12:234-49. [PMID: 25256961 PMCID: PMC4322077 DOI: 10.1007/s13311-014-0305-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [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] [Indexed: 10/24/2022] Open
Abstract
Inhibitors of voltage-gated sodium channels (Na(v)) have been used as anticonvulsants since the 1940s, while potassium channel activators have only been investigated more recently. We here describe the discovery of 2-amino-6-trifluoromethylthio-benzothiazole (SKA-19), a thioanalog of riluzole, as a potent, novel anticonvulsant, which combines the two mechanisms. SKA-19 is a use-dependent NaV channel blocker and an activator of small-conductance Ca(2+)-activated K(+) channels. SKA-19 reduces action potential firing and increases medium afterhyperpolarization in CA1 pyramidal neurons in hippocampal slices. SKA-19 is orally bioavailable and shows activity in a broad range of rodent seizure models. SKA-19 protects against maximal electroshock-induced seizures in both rats (ED50 1.6 mg/kg i.p.; 2.3 mg/kg p.o.) and mice (ED50 4.3 mg/kg p.o.), and is also effective in the 6-Hz model in mice (ED50 12.2 mg/kg), Frings audiogenic seizure-susceptible mice (ED50 2.2 mg/kg), and the hippocampal kindled rat model of complex partial seizures (ED50 5.5 mg/kg). Toxicity tests for abnormal neurological status revealed a therapeutic index (TD50/ED50) of 6-9 following intraperitoneal and of 33 following oral administration. SKA-19 further reduced acute pain in the formalin pain model and raised allodynic threshold in a sciatic nerve ligation model. The anticonvulsant profile of SKA-19 is comparable to riluzole, which similarly affects Na(V) and KCa2 channels, except that SKA-19 has a ~4-fold greater duration of action owing to more prolonged brain levels. Based on these findings we propose that compounds combining KCa2 channel-activating and Na(v) channel-blocking activity exert broad-spectrum anticonvulsant and analgesic effects.
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Affiliation(s)
- Nichole Coleman
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - Hai M. Nguyen
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - Zhengyu Cao
- />State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, People’s Republic of China
| | - Brandon M. Brown
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - David Paul Jenkins
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - Dorota Zolkowska
- />Department of Neurology, School of Medicine, University of California, Davis, CA USA
| | - Yi-Je Chen
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - Brian S. Tanaka
- />Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA USA
| | - Alan L. Goldin
- />Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA USA
| | - Michael A. Rogawski
- />Department of Neurology, School of Medicine, University of California, Davis, CA USA
| | - Isaac N. Pessah
- />Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA USA
| | - Heike Wulff
- />Department of Pharmacology, Genome and Biomedical Sciences Facility, School of Medicine, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
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Nishijo M, Pham TT, Nguyen ATN, Tran NN, Nakagawa H, Hoang LV, Tran AH, Morikawa Y, Ho MD, Kido T, Nguyen MN, Nguyen HM, Nishijo H. 2,3,7,8-Tetrachlorodibenzo-p-dioxin in breast milk increases autistic traits of 3-year-old children in Vietnam. Mol Psychiatry 2014; 19:1220-6. [PMID: 24637425 DOI: 10.1038/mp.2014.18] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 01/18/2014] [Accepted: 02/03/2014] [Indexed: 01/29/2023]
Abstract
Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (⩾3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)--the toxic equivalents (TEQ) levels⩾17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).
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Affiliation(s)
- M Nishijo
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - T T Pham
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - A T N Nguyen
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - N N Tran
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - H Nakagawa
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - L V Hoang
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - A H Tran
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - Y Morikawa
- School of Nursing, Kanazawa Medical University, Ishikawa, Japan
| | - M D Ho
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan
| | - T Kido
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan
| | - M N Nguyen
- 1] Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam [2] System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
| | - H M Nguyen
- 1] Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam [2] System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
| | - H Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
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Chhabra S, Chang SC, Nguyen HM, Huq R, Tanner MR, Londono LM, Estrada R, Dhawan V, Chauhan S, Upadhyay SK, Gindin M, Hotez PJ, Valenzuela JG, Mohanty B, Swarbrick JD, Wulff H, Iadonato SP, Gutman GA, Beeton C, Pennington MW, Norton RS, Chandy KG. Kv1.3 channel-blocking immunomodulatory peptides from parasitic worms: implications for autoimmune diseases. FASEB J 2014; 28:3952-64. [PMID: 24891519 DOI: 10.1096/fj.14-251967] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [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: 04/03/2014] [Accepted: 05/12/2014] [Indexed: 12/26/2022]
Abstract
The voltage-gated potassium (Kv) 1.3 channel is widely regarded as a therapeutic target for immunomodulation in autoimmune diseases. ShK-186, a selective inhibitor of Kv1.3 channels, ameliorates autoimmune diseases in rodent models, and human phase 1 trials of this agent in healthy volunteers have been completed. In this study, we identified and characterized a large family of Stichodactyla helianthus toxin (ShK)-related peptides in parasitic worms. Based on phylogenetic analysis, 2 worm peptides were selected for study: AcK1, a 51-residue peptide expressed in the anterior secretory glands of the dog-infecting hookworm Ancylostoma caninum and the human-infecting hookworm Ancylostoma ceylanicum, and BmK1, the C-terminal domain of a metalloprotease from the filarial worm Brugia malayi. These peptides in solution adopt helical structures closely resembling that of ShK. At doses in the nanomolar-micromolar range, they block native Kv1.3 in human T cells and cloned Kv1.3 stably expressed in L929 mouse fibroblasts. They preferentially suppress the proliferation of rat CCR7(-) effector memory T cells without affecting naive and central memory subsets and inhibit the delayed-type hypersensitivity (DTH) response caused by skin-homing effector memory T cells in rats. Further, they suppress IFNγ production by human T lymphocytes. ShK-related peptides in parasitic worms may contribute to the potential beneficial effects of probiotic parasitic worm therapy in human autoimmune diseases.
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Affiliation(s)
- Sandeep Chhabra
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Shih Chieh Chang
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Hai M Nguyen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA; Department of Pharmacology, University of California, Davis, California, USA
| | - Redwan Huq
- Department of Molecular Physiology and Biophysics, Graduate Program in Molecular Physiology and Biophysics, and
| | - Mark R Tanner
- Department of Molecular Physiology and Biophysics, Interdepartmental Graduate Program in Translational Biology and Molecular Medicine, and
| | | | | | - Vikas Dhawan
- Peptides International, Louisville, Kentucky, USA
| | | | - Sanjeev K Upadhyay
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA
| | - Mariel Gindin
- Department of Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington D.C., USA; and Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Peter J Hotez
- Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Jesus G Valenzuela
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Biswaranjan Mohanty
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - James D Swarbrick
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California, USA
| | | | - George A Gutman
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA
| | | | | | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia;
| | - K George Chandy
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA;
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45
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Nguyen HM, Matsumoto J, Tran AH, Ono T, Nishijo H. sLORETA current source density analysis of evoked potentials for spatial updating in a virtual navigation task. Front Behav Neurosci 2014; 8:66. [PMID: 24624067 PMCID: PMC3941310 DOI: 10.3389/fnbeh.2014.00066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 10/28/2013] [Accepted: 02/16/2014] [Indexed: 02/04/2023] Open
Abstract
Previous studies have reported that multiple brain regions are activated during spatial navigation. However, it is unclear whether these activated brain regions are specifically associated with spatial updating or whether some regions are recruited for parallel cognitive processes. The present study aimed to localize current sources of event related potentials (ERPs) associated with spatial updating specifically. In the control phase of the experiment, electroencephalograms (EEGs) were recorded while subjects sequentially traced 10 blue checkpoints on the streets of a virtual town, which were sequentially connected by a green line, by manipulating a joystick. In the test phase of the experiment, the checkpoints and green line were not indicated. Instead, a tone was presented when the subjects entered the reference points where they were then required to trace the 10 invisible spatial reference points corresponding to the checkpoints. The vertex-positive ERPs with latencies of approximately 340 ms from the moment when the subjects entered the unmarked reference points were significantly larger in the test than in the control phases. Current source density analysis of the ERPs by standardized low-resolution brain electromagnetic tomography (sLORETA) indicated activation of brain regions in the test phase that are associated with place and landmark recognition (entorhinal cortex/hippocampus, parahippocampal and retrosplenial cortices, fusiform, and lingual gyri), detecting self-motion (posterior cingulate and posterior insular cortices), motor planning (superior frontal gyrus, including the medial frontal cortex), and regions that process spatial attention (inferior parietal lobule). The present results provide the first identification of the current sources of ERPs associated with spatial updating, and suggest that multiple systems are active in parallel during spatial updating.
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Affiliation(s)
- Hai M Nguyen
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Anh H Tran
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
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Cao Z, Cui Y, Nguyen HM, Jenkins DP, Wulff H, Pessah IN. Nanomolar bifenthrin alters synchronous Ca2+ oscillations and cortical neuron development independent of sodium channel activity. Mol Pharmacol 2014; 85:630-9. [PMID: 24482397 DOI: 10.1124/mol.113.090076] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bifenthrin, a relatively stable type I pyrethroid that causes tremors and impairs motor activity in rodents, is broadly used. We investigated whether nanomolar bifenthrin alters synchronous Ca(2+) oscillations (SCOs) necessary for activity-dependent dendritic development. Primary mouse cortical neurons were cultured 8 or 9 days in vitro (DIV), loaded with the Ca(2+) indicator Fluo-4, and imaged using a Fluorescence Imaging Plate Reader Tetra. Acute exposure to bifenthrin rapidly increased the frequency of SCOs by 2.7-fold (EC50 = 58 nM) and decreased SCO amplitude by 36%. Changes in SCO properties were independent of modifications in voltage-gated sodium channels since 100 nM bifenthrin had no effect on the whole-cell Na(+) current, nor did it influence neuronal resting membrane potential. The L-type Ca(2+) channel blocker nifedipine failed to ameliorate bifenthrin-triggered SCO activity. By contrast, the metabotropic glutamate receptor (mGluR)5 antagonist MPEP [2-methyl-6-(phenylethynyl)pyridine] normalized bifenthrin-triggered increase in SCO frequency without altering baseline SCO activity, indicating that bifenthrin amplifies mGluR5 signaling independent of Na(+) channel modification. Competitive [AP-5; (-)-2-amino-5-phosphonopentanoic acid] and noncompetitive (dizocilpine, or MK-801 [(5S,10R)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate]) N-methyl-d-aspartate antagonists partially decreased both basal and bifenthrin-triggered SCO frequency increase. Bifenthrin-modified SCO rapidly enhanced the phosphorylation of cAMP response element-binding protein (CREB). Subacute (48 hours) exposure to bifenthrin commencing 2 DIV-enhanced neurite outgrowth and persistently increased SCO frequency and reduced SCO amplitude. Bifenthrin-stimulated neurite outgrowth and CREB phosphorylation were dependent on mGluR5 activity since MPEP normalized both responses. Collectively these data identify a new mechanism by which bifenthrin potently alters Ca(2+) dynamics and Ca(2+)-dependent signaling in cortical neurons that have long term impacts on activity driven neuronal plasticity.
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Affiliation(s)
- Zhengyu Cao
- Department of Molecular Biosciences, School of Veterinary Medicine (Z.C., Y.C., I.N.P.), and Department of Pharmacology, School of Medicine (H.M.N., D.P.J., H.W.), University of California Davis, Davis, California
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47
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Nguyen HM, Chhabra S, Chang SC, Huq RU, Tanner MR, Londono LM, Gindin M, Hotez PJ, Mohanty B, Iadonato SP, Gutman GA, Beeton C, Pennington MW, Norton RS, Chandy KG. Kv1.3-Blocking Peptides from Parasitic Worms Exhibit Immunomodulatory Function. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.4073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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48
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Nguyen HM, Hwang IC, Kweon DK, Park HJ. Enhanced payload of lipid nanocarriers using supersaturated solution prepared by solvent-mediated method. J Microencapsul 2013; 30:657-66. [PMID: 23425086 DOI: 10.3109/02652048.2013.774445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
With the aim to effectively enhance the payload for nanocarriers, supersaturated deltamethrin (SSD) solution was prepared using the solvent-mediated method to produce lipid nanocarriers by a combination method of homogenization and sonication. In this study, deltamethrin was used as an active ingredient, corn oil was used as a lipid medium, soybean lecithin and Tween-80 were used as surfactants. At 25°C, the solubility of deltamethrin in SSD solution prepared by solvent-mediated method was 3.4 times and 1.5 times higher than that in saturated deltamethrin (SD) solution and that in SSD solution prepared by thermal-mediated method, respectively. Therefore, compared to the use of SD solution for the production of nanocarriers, the use of SSD solution significantly enhanced the payload, while keeping the encapsulation efficiency high. Particularly, nanocarriers produced from SSD solution prepared by solvent-mediated method had the higher payload of 2.1 times and 4.4 times compared with preparations using SSD solution prepared by thermal-mediated method and SD solution, respectively.
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Affiliation(s)
- H M Nguyen
- School of Life Sciences and Biotechnology, Korea University , Seoul , South Korea
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Nguyen HM, Galea CA, Schmunk G, Smith BJ, Edwards RA, Norton RS, Chandy KG. Intracellular trafficking of the KV1.3 potassium channel is regulated by the prodomain of a matrix metalloprotease. J Biol Chem 2013; 288:6451-64. [PMID: 23300077 DOI: 10.1074/jbc.m112.421495] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Matrix metalloproteases (MMPs) are endopeptidases that regulate diverse biological processes. Synthesized as zymogens, MMPs become active after removal of their prodomains. Much is known about the metalloprotease activity of these enzymes, but noncanonical functions are poorly defined, and functions of the prodomains have been largely ignored. Here we report a novel metalloprotease-independent, channel-modulating function for the prodomain of MMP23 (MMP23-PD). Whole-cell patch clamping and confocal microscopy, coupled with deletion analysis, demonstrate that MMP23-PD suppresses the voltage-gated potassium channel KV1.3, but not the closely related KV1.2 channel, by trapping the channel intracellularly. Studies with KV1.2-1.3 chimeras suggest that MMP23-PD requires the presence of the KV1.3 region from the S5 trans-membrane segment to the C terminus to modulate KV1.3 channel function. NMR studies of MMP23-PD reveal a single, kinked trans-membrane α-helix, joined by a short linker to a juxtamembrane α-helix, which is associated with the surface of the membrane and protected from exchange with the solvent. The topological similarity of MMP23-PD to KCNE1, KCNE2, and KCNE4 proteins that trap KV1.3, KV1.4, KV3.3, and KV3.4 channels early in the secretory pathway suggests a shared mechanism of channel regulation. MMP23 and KV1.3 expression is enhanced and overlapping in colorectal cancers where the interaction of the two proteins could affect cell function.
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Affiliation(s)
- Hai M Nguyen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California92697, USA
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Schmunk G, Nguyen HM, Galea CA, Smith BJ, Edwards RA, Norton R, Chandy GK. Regulation of a Potassium Channel by the Pro-Domain of a Matrix Metalloprotease. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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