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Lee YS, Wu HC, Huang SJ, Hsiao G, Chi WC, Lee TH. Anti-inflammatory constituents from a sea anemone-derived fungus Arthrinium arundinis MA30. PHYTOCHEMISTRY 2024; 219:113998. [PMID: 38253160 DOI: 10.1016/j.phytochem.2024.113998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/19/2024] [Accepted: 01/19/2024] [Indexed: 01/24/2024]
Abstract
In this study, preliminary field-sampling of bioactive fungal strains and bioassay-guided selection were conducted. A number of fungal strains were isolated from sea anemones along the northeastern coast of Badouzi, Keelung, Taiwan. Among them, Arthrinium arundinis MA30 showed significant anti-inflammatory activity and was thus selected for further chemical investigation. After a series of purification and isolation using different chromatographic techniques on the fermented products of A. arundinis MA30, thirty-one compounds were identified, five of which were previously unreported, including arthrinoic acid, hexylaconitic anhydride methyl ester, (3S,8R)-8-hydroxy-3-carboxy-2-methylenenonanoic acid, and arthripenoids G and H. These compounds were subjected to comprehensive spectroscopic data analysis. Of all the isolates, 1,3,5,6-tetrahydroxy-8-methylxanthone and arthripenoid C demonstrated the most distinctive inhibitory activities against nitric oxide production in mouse microglial BV-2 cells, with their respective inhibitory rates being 71% and 81% at 10 μM concentration, and their respective IC50 values were further determined to be 5.3 ± 0.6 and 1.6 ± 0.4 μM. These compounds showed no significant cytotoxicity, and curcumin was used as a positive control in this study.
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Affiliation(s)
- Yuen-Sing Lee
- Institute of Fisheries Science, College of Life Science, National Taiwan University, Taipei 106, Taiwan.
| | - Ho-Cheng Wu
- Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan; Ph.D. Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan; School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Shu-Jung Huang
- Institute of Fisheries Science, College of Life Science, National Taiwan University, Taipei 106, Taiwan.
| | - George Hsiao
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan; Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan.
| | - Wei-Chiung Chi
- Department of Food Science, National Quemoy University, Kinmen 892, Taiwan.
| | - Tzong-Huei Lee
- Institute of Fisheries Science, College of Life Science, National Taiwan University, Taipei 106, Taiwan.
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Cheng JH, Wu HC, Yen CH, Hwang TL, Ko HH, Chang HS. Chemical Constituents with Anti-Lipid Droplet Accumulation and Anti-Inflammatory Activity from Elaeagnus glabra. PLANTS (BASEL, SWITZERLAND) 2023; 12:2943. [PMID: 37631155 PMCID: PMC10458971 DOI: 10.3390/plants12162943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a type of steatosis caused by excess lipids accumulating in the liver. The prevalence of NAFLD has increased annually due to modern lifestyles and a lack of adequate medical treatment. Thus, we were motivated to investigate the bioactive components of Formosan plants that could attenuate lipid droplet (LD) accumulation. In a series of screenings of 3000 methanolic extracts from the Formosan plant extract bank for anti-LD accumulation activity, the methanolic extract of aerial parts of Elaeagnus glabra Thunb. showed excellent anti-LD accumulation activity. E. glabra is an evergreen shrub on which only a few phytochemical and biological studies have been conducted. Here, one new flavonoid (1), two new triterpenoids (2 and 3), and 35 known compounds (4-38) were isolated from the ethyl acetate layer of aerial parts of E. glabra via a bioassay-guided fractionation process. Their structures were characterized by 1D and 2D NMR, UV, IR, and MS data. Among the isolated compounds, methyl pheophorbide a (37) efficiently reduced the normalized LD content to 0.3% with a concentration of 20 μM in AML12 cell lines without significant cytotoxic effects. 3-O-(E)-Caffeoyloleanolic acid (13) and methyl pheophorbide a (37) showed inhibitory effects on superoxide anion generation or elastase release in fMLP/CB-treated human neutrophils (IC50 < 3.0 μM); they displayed effects similar to those of the positive control, namely, LY294002. These findings indicate that E. glabra can be used for developing a new botanical drug for managing LD accumulation and against inflammation-related diseases.
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Affiliation(s)
- Ju-Hsin Cheng
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (J.-H.C.); (H.-C.W.); (H.-H.K.)
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan;
| | - Ho-Cheng Wu
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (J.-H.C.); (H.-C.W.); (H.-H.K.)
- Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan
| | - Chia-Hung Yen
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan;
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
| | - Tsong-Long Hwang
- Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Research Center for Chinese Herbal Medicine, Graduate Institute of Health Industry Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan
- Department of Anesthesiology, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Horng-Huey Ko
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (J.-H.C.); (H.-C.W.); (H.-H.K.)
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
| | - Hsun-Shuo Chang
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (J.-H.C.); (H.-C.W.); (H.-H.K.)
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan;
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
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Hsieh CJ, Giannakoulias S, Petersson EJ, Mach RH. Computational Chemistry for the Identification of Lead Compounds for Radiotracer Development. Pharmaceuticals (Basel) 2023; 16:317. [PMID: 37259459 PMCID: PMC9964981 DOI: 10.3390/ph16020317] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/15/2023] [Accepted: 02/16/2023] [Indexed: 11/19/2023] Open
Abstract
The use of computer-aided drug design (CADD) for the identification of lead compounds in radiotracer development is steadily increasing. Traditional CADD methods, such as structure-based and ligand-based virtual screening and optimization, have been successfully utilized in many drug discovery programs and are highlighted throughout this review. First, we discuss the use of virtual screening for hit identification at the beginning of drug discovery programs. This is followed by an analysis of how the hits derived from virtual screening can be filtered and culled to highly probable candidates to test in in vitro assays. We then illustrate how CADD can be used to optimize the potency of experimentally validated hit compounds from virtual screening for use in positron emission tomography (PET). Finally, we conclude with a survey of the newest techniques in CADD employing machine learning (ML).
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Affiliation(s)
- Chia-Ju Hsieh
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sam Giannakoulias
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - E. James Petersson
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert H. Mach
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Juza R, Musilek K, Mezeiova E, Soukup O, Korabecny J. Recent advances in dopamine D 2 receptor ligands in the treatment of neuropsychiatric disorders. Med Res Rev 2023; 43:55-211. [PMID: 36111795 DOI: 10.1002/med.21923] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 07/29/2022] [Accepted: 08/09/2022] [Indexed: 02/04/2023]
Abstract
Dopamine is a biologically active amine synthesized in the central and peripheral nervous system. This biogenic monoamine acts by activating five types of dopamine receptors (D1-5 Rs), which belong to the G protein-coupled receptor family. Antagonists and partial agonists of D2 Rs are used to treat schizophrenia, Parkinson's disease, depression, and anxiety. The typical pharmacophore with high D2 R affinity comprises four main areas, namely aromatic moiety, cyclic amine, central linker and aromatic/heteroaromatic lipophilic fragment. From the literature reviewed herein, we can conclude that 4-(2,3-dichlorophenyl), 4-(2-methoxyphenyl)-, 4-(benzo[b]thiophen-4-yl)-1-substituted piperazine, and 4-(6-fluorobenzo[d]isoxazol-3-yl)piperidine moieties are critical for high D2 R affinity. Four to six atoms chains are optimal for D2 R affinity with 4-butoxyl as the most pronounced one. The bicyclic aromatic/heteroaromatic systems are most frequently occurring as lipophilic appendages to retain high D2 R affinity. In this review, we provide a thorough overview of the therapeutic potential of D2 R modulators in the treatment of the aforementioned disorders. In addition, this review summarizes current knowledge about these diseases, with a focus on the dopaminergic pathway underlying these pathologies. Major attention is paid to the structure, function, and pharmacology of novel D2 R ligands, which have been developed in the last decade (2010-2021), and belong to the 1,4-disubstituted aromatic cyclic amine group. Due to the abundance of data, allosteric D2 R ligands and D2 R modulators from patents are not discussed in this review.
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Affiliation(s)
- Radomir Juza
- Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic.,Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Musilek
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Eva Mezeiova
- Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic.,Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Ondrej Soukup
- Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Jan Korabecny
- Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic.,Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
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Glycoconjugate journal special issue on: the glycobiology of Parkinson's disease. Glycoconj J 2021; 39:55-74. [PMID: 34757539 DOI: 10.1007/s10719-021-10024-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 09/14/2021] [Accepted: 09/24/2021] [Indexed: 10/19/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder that affects over 10 million aging people worldwide. This condition is characterized by the degeneration of dopaminergic neurons in the pars compacta region of the substantia nigra (SNpc) and by aggregation of proteins, commonly α-synuclein (SNCA). The formation of Lewy bodies that encapsulate aggregated proteins in lipid vesicles is a hallmark of PD. Glycosylation of proteins and neuroinflammation are involved in the pathogenesis. SNCA has many posttranslational modifications and interacts with components of membranes that affect aggregation. The large membrane lipid dolichol accumulates in the brain upon age and has a significant effect on membrane structure. The replacement of dopamine and dopaminergic neurons are at the forefront of therapeutic development. This review examines the role of membrane lipids, glycolipids, glycoproteins and dopamine in the aggregation of SNCA and development of PD. We discuss the SNCA-dopamine-neuromelanin-dolichol axis and the role of membranes in neuronal stem cells that could be a regenerative therapy for PD patients.
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Hayatshahi HS, Luedtke RR, Taylor M, Chen PJ, Blass BE, Liu J. Factors Governing Selectivity of Dopamine Receptor Binding Compounds for D2R and D3R Subtypes. J Chem Inf Model 2021; 61:2829-2843. [PMID: 33988991 DOI: 10.1021/acs.jcim.1c00036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Targeting the D3 dopamine receptor (D3R) is a promising pharmacotherapeutic strategy for the treatment of many disorders. The structure of the D3R is similar to the D2 dopamine receptor (D2R), especially in the transmembrane spanning regions that form the orthosteric binding site, making it difficult to identify D3R selective pharmacotherapeutic agents. Here, we examine the molecular basis for the high affinity D3R binding and D3R vs D2R binding selectivity of substituted phenylpiperazine thiopheneamides. We show that removing the thiophenearylamide portion of the ligand consistently decreases the affinity of these ligands at D3R, while not affecting their affinity at the D2R. Our long (>10 μs) molecular dynamics simulations demonstrated that both dopamine receptor subtypes adopt two major conformations that we refer to as closed or open conformations, with D3R sampling the open conformation more frequently than D2R. The binding of ligands with conjoined orthosteric-allosteric binding moieties causes the closed conformation to populate more often in the trajectories. Also, significant differences were observed in the extracellular loops (ECL) of these two receptor subtypes leading to the identification of several residues that contribute differently to the ligand binding for the two receptors that could potentially contribute to ligand binding selectivity. Our observations also suggest that the displacement of ordered water in the binding pocket of D3R contributes to the affinity of the compounds containing an allosteric binding motif. These studies provide a better understanding of how a bitopic mode of engagement can determine ligands that bind selectively to D2 and D3 dopamine receptor subtypes.
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Affiliation(s)
- Hamed S Hayatshahi
- Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, Texas 76107, United States
| | - Robert R Luedtke
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, Texas 76107, United States
| | - Michelle Taylor
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, Texas 76107, United States
| | - Peng-Jen Chen
- Moulder Center for Drug Discovery Research, Department of Pharmaceutical Sciences, Temple University School of Pharmacy, 3307 North Broad Street, Philadelphia, Pennsylvania 19140, United States
| | - Benjamin E Blass
- Moulder Center for Drug Discovery Research, Department of Pharmaceutical Sciences, Temple University School of Pharmacy, 3307 North Broad Street, Philadelphia, Pennsylvania 19140, United States
| | - Jin Liu
- Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, Texas 76107, United States
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Bashetti N, Shanmukha Kumar J, Seelam NV, Prasanna B, Mintz A, Damuka N, Devanathan S, Solingapuram Sai KK. One-pot synthesis of novel tert-butyl-4-substituted phenyl-1H-1,2,3-triazolo piperazine/piperidine carboxylates, potential GPR119 agonists. Bioorg Med Chem Lett 2019; 29:126707. [DOI: 10.1016/j.bmcl.2019.126707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/12/2019] [Accepted: 09/14/2019] [Indexed: 01/24/2023]
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Hayatshahi HS, Xu K, Griffin SA, Taylor M, Mach RH, Liu J, Luedtke RR. Analogues of Arylamide Phenylpiperazine Ligands To Investigate the Factors Influencing D3 Dopamine Receptor Bitropic Binding and Receptor Subtype Selectivity. ACS Chem Neurosci 2018; 9:2972-2983. [PMID: 30010318 DOI: 10.1021/acschemneuro.8b00142] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We have previously reported on the ability of arylamide phenylpiperazines to bind selectively to the D3 versus the D2 dopamine receptor subtype. For these studies, we used LS-3-134 as the prototypic arylamide phenylpiperazine ligand because it binds with high affinity at D3 dopamine receptor (0.17 nM) and exhibits >150-fold D3 vs D2 receptor binding selectivity. Our goal was to investigate how the composition and size of the nonaromatic ring structure at the piperazine position of substituted phenylpiperazine analogues might influence binding affinity at the human D2 and D3 dopamine receptors. Two factors were identified as being important for determining the binding affinity of bitropic arylamide phenylpiperazines at the dopamine D3 receptor subtype. One factor was the strength of the salt bridge between the highly conserved residue Asp3.32 with the protonated nitrogen of the nonaromatic ring at the piperazine position. The second factor was the configuration of the unbound ligand in an aqueous solution. These two factors were found to be related to the logarithm of the affinities using a simple correlation model, which could be useful when designing high affinity subtype selective bitropic ligands. While this model is based upon the interaction of arylamide phenylpiperazines with the D2 and D3 D2-like dopamine receptor subtypes, it provides insights into the complexity of the factors that define a bitropic mode of the binding at GPCRs.
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Affiliation(s)
- Hamed S. Hayatshahi
- Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
| | - Kuiying Xu
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Suzy A. Griffin
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
| | - Michelle Taylor
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
| | - Robert H. Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Jin Liu
- Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
| | - Robert R. Luedtke
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
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Chemical Constituents from the Stems of Tinospora sinensis and Their Bioactivity. Molecules 2018; 23:molecules23102541. [PMID: 30301176 PMCID: PMC6222598 DOI: 10.3390/molecules23102541] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/01/2018] [Accepted: 10/02/2018] [Indexed: 11/23/2022] Open
Abstract
Fifty-seven compounds were purified from the stems of Tinospora sinensis, including three new compounds characterized as a lignan (1), a pyrrole alkaloid (11), and a benzenoid (17), respectively. Their structures were elucidated and established by various spectroscopic and spectrometric analytical methods. Among the isolates, fifteen compounds were examined for their anti-inflammatory potential in vitro. The results showed that several compounds displayed moderate inhibition of N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release.
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Reddy AGK, Krishna J, Satyanarayana G. One-pot Jeffery-Heck and Reduction Sequence: Synthesis of Alcohols and Applied to the Synthesis of Flavan Natural Products. ChemistrySelect 2016. [DOI: 10.1002/slct.201600100] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alavala Gopi Krishna Reddy
- Department of Chemistry; Indian Institute of Technology; Hyderabad; Kandi - 502 285, Sangareddy, Telangana INDIA
| | - Jonnada Krishna
- Department of Chemistry; Indian Institute of Technology; Hyderabad; Kandi - 502 285, Sangareddy, Telangana INDIA
| | - Gedu Satyanarayana
- Department of Chemistry; Indian Institute of Technology; Hyderabad; Kandi - 502 285, Sangareddy, Telangana INDIA
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Rangel-Barajas C, Malik M, Mach RH, Luedtke RR. Pharmacological modulation of abnormal involuntary DOI-induced head twitch response movements in male DBA/2J mice: II. Effects of D3 dopamine receptor selective compounds. Neuropharmacology 2015; 93:179-90. [PMID: 25698528 DOI: 10.1016/j.neuropharm.2014.10.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/28/2014] [Accepted: 10/30/2014] [Indexed: 12/27/2022]
Abstract
We recently reported on the characterization of the hallucinogen 2,5-dimethoxy-4-methylamphetamine's (DOI) ability to elicit a head twitch response (HTR) in DBA/2J mice and the ability of D2 vs. D3 dopamine receptor selective compounds to modulate that response. For these studies, the ability of D3 vs. D2 dopamine receptor selective compounds to attenuate the DOI-dependent HTR was examined. WC 10, a D3 dopamine receptor weak partial agonist with 40-fold binding selectivity for D3 vs. D2 dopamine receptors, produced a dose-dependent decrease in the DOI-induced HTR (IC50 = 3.7 mg/kg). WC 44, a D3 receptor selective full agonist, also inhibited the DOI-induced HTR (IC50 = 5.1 mg/kg). The effect of two D3 receptor selective partial agonists, LAX-4-136 and WW-III-55, were also evaluated. These analogs exhibit 150-fold and 800-fold D3 vs. D2 binding selectivity, respectively. Both compounds inhibited the HTR with similar potency but with different maximum efficacies. At 10 mg/kg WW-III-55 inhibited the HTR by 95%, while LAX-4-136 administration resulted in a 50% reduction. In addition, DOI (5 mg/kg) was administered at various times after LAX-4-136 or WW-III-55 administration to compare the duration of action. The homopiperazine analog LAX-4-136 exhibited greater stability. An assessment of our test compounds on motor performance and coordination was performed using a rotarod test. None of the D3 dopamine receptor selective compounds significantly altered latency to fall, suggesting that these compounds a) did not attenuate the DOI-dependent HTR due to sedative or adverse motor effects and b) may have antipsychotic/antihallucinogenic activity.
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Affiliation(s)
- Claudia Rangel-Barajas
- University of North Texas Health Science Center, Department of Pharmacology and Neuroscience, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
| | - Maninder Malik
- University of North Texas Health Science Center, Department of Pharmacology and Neuroscience, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
| | - Robert H Mach
- Radiochemistry Laboratory, Neurology Department, University of Pennsylvania School of Medicine, Chemistry Building, 231 S. 34th Street, Philadelphia, PA 19104, USA
| | - Robert R Luedtke
- University of North Texas Health Science Center, Department of Pharmacology and Neuroscience, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
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