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Li SY, Shi WJ, Ma DD, Zhang JG, Lu ZJ, Long XB, Liu X, Huang CS, Ying GG. Effects of New Psychoactive Substance Esketamine on Behaviors and Transcription of Genes in Dopamine and GABA Pathways in Zebrafish Larvae. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2024; 112:51. [PMID: 38556558 DOI: 10.1007/s00128-024-03883-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 03/07/2024] [Indexed: 04/02/2024]
Abstract
Esketamine (ESK) is the S-enantiomer of ketamine racemate (a new psychoactive substance) that can result in illusions, and alter hearing, vision, and proprioception in human and mouse. Up to now, the neurotoxicity caused by ESK at environmental level in fish is still unclear. This work studied the effects of ESK on behaviors and transcriptions of genes in dopamine and GABA pathways in zebrafish larvae at ranging from 12.4 ng L- 1 to 11141.1 ng L- 1 for 7 days post fertilization (dpf). The results showed that ESK at 12.4 ng L- 1 significantly reduced the touch response of the larvae at 48 hpf. ESK at 12.4 ng L- 1 also reduced the time and distance of larvae swimming at the outer zone during light period, which implied that ESK might potentially decrease the anxiety level of larvae. In addition, ESK increased the transcription of th, ddc, drd1a, drd3 and drd4a in dopamine pathway. Similarly, ESK raised the transcription of slc6a1b, slc6a13 and slc12a2 in GABA pathway. This study suggested that ESK could affect the heart rate and behaviors accompanying with transcriptional alterations of genes in DA and GABA pathways at early-staged zebrafish, which resulted in neurotoxicity in zebrafish larvae.
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Affiliation(s)
- Si-Ying Li
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Wen-Jun Shi
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China.
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China.
| | - Dong-Dong Ma
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Jin-Ge Zhang
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Zhi-Jie Lu
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Xiao-Bing Long
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Xin Liu
- Anti-Drug Technology Center of Guangdong Province and National Anti-Drug Laboratory Guangdong Regional Center, Guangdong Provincial Key Laboratory of Psychoactive Substances Monitoring and Safety, Guangzhou, 510230, China
| | - Chu-Shu Huang
- Anti-Drug Technology Center of Guangdong Province and National Anti-Drug Laboratory Guangdong Regional Center, Guangdong Provincial Key Laboratory of Psychoactive Substances Monitoring and Safety, Guangzhou, 510230, China
| | - Guang-Guo Ying
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, SCNU Environmental Research Institute, South China Normal University, Guangzhou, 510006, China.
- School of Environment, South China Normal University, University Town, Guangzhou, 510006, China.
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Cho W, Liu F, Hendrix A, McCray B, Asrat T, Connaughton V, Zestos AG. Timed Electrodeposition of PEDOT:Nafion onto Carbon Fiber-Microelectrodes Enhances Dopamine Detection in Zebrafish Retina. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2020; 167:115501. [PMID: 33927449 PMCID: PMC8081298 DOI: 10.1149/1945-7111/aba33d] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Carbon fiber-microelectrodes (CFMEs) are one of the standards for the detection of neurotransmitters such as dopamine (DA). In this study, we demonstrate that CFMEs electrodeposited with poly (3,4-ethylenedioxythiophene) (PEDOT) in the presence of Nafion exhibit enhanced sensitivity for DA detection. Scanning electron microscopy (SEM) revealed the smooth outer surface morphologies of polymer coatings, which filled in the ridges and grooves of the bare unmodified carbon electrode and energy-dispersive X-ray spectroscopy (EDX) confirmed PEDOT:Nafion incorporation. PEDOT:Nafion coated CMFEs exhibited a statistically enhanced two-fold increase in DA sensitivity compared to unmodified microelectrodes, with stability and integrity of the coated microelectrodes maintained for at least 4 h. A scan rate test revealed a linear relationship with peak DA oxidative current (5 μM), indicating adsorption control of DA to the surface of the PEDOT:Nafion electrode. As proof of principle, PEDOT:Nafion coated electrodes were used to detect potassium chloride (KCl)-induced DA release in zebrafish (Danio rerio) retinal tissue ex vivo, thus illustrating their applicability as biosensors.
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Affiliation(s)
- Whirang Cho
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Favian Liu
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Aaron Hendrix
- Department of Biology, American University, Washington, D.C. 20016, United States of America
| | - Brazil McCray
- Department of Biology, American University, Washington, D.C. 20016, United States of America
| | - Thomas Asrat
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Victoria Connaughton
- Department of Biology, American University, Washington, D.C. 20016, United States of America
- Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States of America
| | - Alexander G. Zestos
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
- Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States of America
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Wonnenberg PM, Zestos AG. Polymer-Modified Carbon Fiber Microelectrodes for Neurochemical Detection of Dopamine and Metabolites. ECS TRANSACTIONS 2020; 97:901-927. [PMID: 33953827 PMCID: PMC8096166 DOI: 10.1149/09707.0901ecst] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Carbon-fiber microelectrodes (CFMEs) are considered to be the standard electrodes for neurotransmitter detection. Fast-scan cyclic voltammetry (FSCV), an electro analytical method, has the ability to follow neurochemical dynamics in real time using CFMEs. Improvements in neurochemical detection with CFMEs were previously made through the coating of polymers onto the surface of the carbon-fiber. Polymers such as PEI, PEDOT, and Nafion were electrodeposited onto the surface of the electrodes to enhance neurochemical detection. This work demonstrates applications for enhancements in co-detection of similarly structured neurochemicals such as dopamine, DOPAL, 3-methoxytyramine, DOPAC, and other neurotransmitters. Manipulating the charge and surface structure of the carbon electrode allows for the improvement of sensitivity and selectivity of neurotransmitter detection. The analytes are detected and differentiated by the shape and the peak positions of their respective cyclic voltammograms.
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Affiliation(s)
- P M Wonnenberg
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, District of Columbia 20016, USA
| | - A G Zestos
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, District of Columbia 20016, USA
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Zhang L, Qu X. The Effects of High Lighting on the Development of Form-Deprivation Myopia in Guinea Pigs. Invest Ophthalmol Vis Sci 2020; 60:4319-4327. [PMID: 31622468 DOI: 10.1167/iovs.18-25258] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate the effects of high ambient lighting on refraction and ocular biometry in guinea pig models of form-deprivation myopia (FDM). Methods Forty 3-week-old guinea pigs were randomly assigned to groups exposed to either high light (HL, 10,000 lux) or normal light (NL, 500 lux) with normal vision or form deprivation. Throughout the 10-week rearing period, animals were exposed to high light or normal light for 12 hours with a 12-hour light/dark cycle. Refraction, axial length (AL), and radius of corneal curvature (CCR) were measured by cycloplegic retinoscopy, A-scan ultrasonography, and keratometer, respectively. Results At the end of treatment, form-deprived eyes under high ambient lighting exhibited more hyperopic refraction and shorter AL than those under normal ambient lighting (2.06 ± 1.68 diopters [D; mean ± SD] vs. -0.59 ± 1.56 D, P < 0.001; 8.36 ± 0.13 mm vs. 8.56 ± 0.16 mm, P < 0.001). Deprived eyes under high ambient lighting were relatively more myopic than their contralateral control eyes at the end of treatment (2.06 ± 1.68 D vs. 5.44 ± 0.66 D, P < 0.001). High lighting induced a significant hyperopic shift in normal eyes after 4 weeks of exposure. There were no significant differences in CCR between eyes exposed to high and normal light, nor between deprived eyes and contralateral eyes. Conclusions High ambient lighting could retard, but not fully inhibit, the development of FDM. High light levels contributed to a greater hyperopic shift in normal eyes during the first 4 weeks of treatment. Corneal curvature was unaffected by either high ambient lighting or form deprivation.
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Affiliation(s)
- Luoli Zhang
- Department of Ophthalmology and Vision Science, Eye & ENT Hospital, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Fudan University, Shanghai, China.,Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Xiaomei Qu
- Department of Ophthalmology and Vision Science, Eye & ENT Hospital, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Fudan University, Shanghai, China.,Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
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Lahne M, Piekos SM, O'Neill J, Ackerman KM, Hyde DR. Photo-regulation of rod precursor cell proliferation. Exp Eye Res 2018; 178:148-159. [PMID: 30267656 DOI: 10.1016/j.exer.2018.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/18/2018] [Accepted: 09/26/2018] [Indexed: 11/29/2022]
Abstract
Teleosts are unique in their ability to undergo persistent neurogenesis and to regenerate damaged and lost retinal neurons in adults. This contrasts with the human retina, which is incapable of replacing lost retinal neurons causing vision loss/blindness in the affected individuals. Two cell populations within the adult teleost retina generate new retinal neurons throughout life. Stem cells within the ciliary marginal zone give rise to all retinal cell types except for rod photoreceptors, which are produced by the resident Müller glia that are located within the inner nuclear layer of the entire retina. Understanding the mechanisms that regulate the generation of photoreceptors in the adult teleost retina may ultimately aid developing strategies to overcome vision loss in diseases such as retinitis pigmentosa. Here, we investigated whether photic deprivation alters the proliferative capacity of rod precursor cells, which are generated from Müller glia. In dark-adapted retinas, rod precursor cell proliferation increased, while the number of proliferating Müller glia and their derived olig2:EGFP-positive neuronal progenitor cells was not significantly changed. Cell death of rod photoreceptors was excluded as the inducer of rod precursor cell proliferation, as the number of TUNEL-positive cells and l-plastin-positive microglia in both the outer (ONL) and inner nuclear layer (INL) remained at a similar level throughout the dark-adaptation timecourse. Rod precursor cell proliferation in response to dark-adaptation was characterized by an increased number of EdU-positive cells, i.e. cells that were undergoing DNA replication. These proliferating rod precursor cells in dark-adapted zebrafish differentiated into rod photoreceptors at a comparable percentage and in a similar time frame as those maintained under standard light conditions suggesting that the cell cycle did not stall in dark-adapted retinas. Inhibition of IGF1-receptor signaling reduced the dark-adaptation-mediated proliferation response; however, caloric restriction which has been suggested to be integrated by the IGF1/growth hormone signaling axis did not influence rod precursor cell proliferation in dark-adapted retinas, as similar numbers were observed in starved and normal fed zebrafish. In summary, photic deprivation induces cell cycle entry of rod precursor cells via IGF1-receptor signaling independent of Müller glia proliferation.
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Affiliation(s)
- Manuela Lahne
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Samantha M Piekos
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - John O'Neill
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Kristin M Ackerman
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - David R Hyde
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA.
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Tsang B, Ansari R, Azhar A, Gerlai R. Drinking in the morning versus evening: Time-dependent differential effects of acute alcohol administration on the behavior of zebrafish. Pharmacol Biochem Behav 2018; 175:174-185. [PMID: 30153446 DOI: 10.1016/j.pbb.2018.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022]
Abstract
Alcohol (ethanol) abuse remains to be a leading cause of medical, including mental, problems throughout the world. Whether alcohol consumption leads to chronic use, and subsequent alcohol dependency and abuse is known to be influenced by the acute effects of this drug. Numerous factors may influence how alcohol administered acutely affects the individual. For example, the mechanisms engaged by drugs of abuse, e.g. cocaine as well as alcohol, have been shown to overlap with those underlying circadian rhythm, and conversely, the effects of these drugs may be dependent upon the time of day of their consumption. To investigate the interaction between circadian rhythm and alcohol, here we employ a simple vertebrate model organism that was previously successfully utilized in other aspects of alcohol research, the zebrafish. We expose zebrafish to alcohol for 20 min in the morning or in the evening, and analyze the effects of this treatment by comparing 1% (vol/vol) alcohol-treated and control (alcohol naive) zebrafish. We record numerous swim path parameters, and report, for the first time, that the time of day of alcohol administration differentially affects certain behavioral parameters, enhancing some while blunting others. Our results suggest a complex interaction between circadian dependent and alcohol engaged mechanisms, findings that represent both practical complications as well as opportunities for understanding how alcohol affects brain function and behavior of vertebrates.
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Affiliation(s)
- Benjamin Tsang
- Department of Psychology, University of Toronto Mississauga, Canada
| | - Rida Ansari
- Department of Psychology, University of Toronto Mississauga, Canada
| | - Amna Azhar
- Department of Psychology, University of Toronto Mississauga, Canada
| | - Robert Gerlai
- Department of Psychology, University of Toronto Mississauga, Canada; Cell and Systems Biology Department, University of Toronto, Canada.
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Rodrigues NR, Macedo GE, Martins IK, Gomes KK, de Carvalho NR, Posser T, Franco JL. Short-term sleep deprivation with exposure to nocturnal light alters mitochondrial bioenergetics in Drosophila. Free Radic Biol Med 2018; 120:395-406. [PMID: 29655867 DOI: 10.1016/j.freeradbiomed.2018.04.549] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/26/2018] [Accepted: 04/11/2018] [Indexed: 02/07/2023]
Abstract
Many studies have shown the effects of sleep deprivation in several aspects of health and disease. However, little is known about how mitochondrial bioenergetics function is affected under this condition. To clarify this, we developed a simple model of short-term sleep deprivation, in which fruit-flies were submitted to a nocturnal light condition and then mitochondrial parameters were assessed by high resolution respirometry (HRR). Exposure of flies to constant light was able to alter sleep patterns, causing locomotor deficits, increasing ROS production and lipid peroxidation, affecting mitochondrial activity, antioxidant defense enzymes and caspase activity. HRR analysis showed that sleep deprivation affected mitochondrial bioenergetics capacity, decreasing respiration at oxidative phosphorylation (OXPHOS) and electron transport system (ETS). In addition, the expression of genes involved in the response to oxidative stress and apoptosis were increased. Thus, our results suggest a connection between sleep deprivation and oxidative stress, pointing to mitochondria as a possible target of this relationship.
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Affiliation(s)
- Nathane Rosa Rodrigues
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil; Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
| | - Giulianna Echeverria Macedo
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil
| | - Illana Kemmerich Martins
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil
| | - Karen Kich Gomes
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil
| | - Nélson Rodrigues de Carvalho
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil
| | - Thaís Posser
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil
| | - Jeferson Luis Franco
- Oxidative Stress and Cell Signaling Research Group, Centro Interdisciplinar de Pesquisas em Biotecnologia - CIPBIOTEC, Universidade Federal do Pampa, Campus São Gabriel, RS, Brazil; Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
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Peimani AR, Zoidl G, Rezai P. A microfluidic device to study electrotaxis and dopaminergic system of zebrafish larvae. BIOMICROFLUIDICS 2018; 12:014113. [PMID: 29464011 PMCID: PMC5803004 DOI: 10.1063/1.5016381] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
The zebrafish is a lower vertebrate model organism offering multiple applications for both fundamental and biomedical research into the nervous system from genes to behaviour. Investigation of zebrafish larvae's movement in response to various stimuli, which involves the dopaminergic system, is of interest in the field of sensory-motor integration. Nevertheless, the conventional methods of movement screening in Petri dishes and multi-well plates are mostly qualitative, uncontrollable, and inaccurate in terms of stimulus delivery and response analysis. We recently presented a microfluidic device built as a versatile platform for fluid flow stimulation and high speed time-lapse imaging of rheotaxis behaviour of zebrafish larvae. Here, we describe for the first time that this microfluidic device can also be used to test zebrafish larvae's sense of the electric field and electrotaxis in a systemic manner. We further show that electrotaxis is correlated with the dopamine signalling pathway in a time of day dependent manner and by selectively involving the D2-like dopamine receptors. The primary outcomes of this research opens avenues to study the molecular and physiological basis of electrotaxis, the effects of known agonist and antagonist compounds on the dopaminergic system, and the screen of novel pharmacological tools in the context of neurodegenerative disorders. We propose that this microfluidic device has broad application potential, including the investigation of complex stimuli, biological pathways, behaviors, and brain disorders.
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Affiliation(s)
- Amir Reza Peimani
- Department of Mechanical Engineering, York University, Toronto, Ontario M3J 1P3, Canada
| | - Georg Zoidl
- Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Pouya Rezai
- Department of Mechanical Engineering, York University, Toronto, Ontario M3J 1P3, Canada
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Semenova S, Rozov S, Panula P. Distribution, properties, and inhibitor sensitivity of zebrafish catechol-O-methyl transferases (COMT). Biochem Pharmacol 2017; 145:147-157. [PMID: 28844929 DOI: 10.1016/j.bcp.2017.08.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/14/2017] [Indexed: 12/24/2022]
Abstract
Catechol-O-methyltransferase (COMT; EC 2.1.1.6) is an enzyme with multiple functions in vertebrates. COMT methylates and thus inactivates catecholamine neurotransmitters and metabolizes xenobiotic catechols. Gene polymorphism rs4680 that influences the enzymatic activity of COMT affects cognition and behavior in humans. The zebrafish is widely used as an experimental animal in many areas of biomedical research, but most aspects of COMT function in this species have remained uncharacterized. We hypothesized that both comt genes play essential roles in zebrafish. Both comt-a and comt-b were widely expressed in zebrafish tissues, but their relative abundance varied considerably. Homogenates of zebrafish organs, including the brain, showed enzymatic COMT activity that was the highest in the liver and kidney. Treatment of larval zebrafish with the COMT inhibitor Ro41-0960 shifted the balance of catecholamine metabolic pathways towards increased oxidative metabolism. Whole-body concentrations of dioxyphenylacetic acid (DOPAC), a product of dopamine oxidation, were increased in the inhibitor-treated larvae, although the dopamine levels were unchanged. Thus, COMT is likely to participate in the processing of catecholamine neurotransmitters in the zebrafish, but the inhibition of COMT in larval fish is compensated efficiently and does not have pronounced effects on dopamine levels.
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Affiliation(s)
- Svetlana Semenova
- Department of Anatomy and Neuroscience Center, University of Helsinki, FI-00014 Helsinki, Finland
| | - Stanislav Rozov
- Department of Anatomy and Neuroscience Center, University of Helsinki, FI-00014 Helsinki, Finland
| | - Pertti Panula
- Department of Anatomy and Neuroscience Center, University of Helsinki, FI-00014 Helsinki, Finland.
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