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One-Pot Phosphate-Mediated Synthesis of Novel 1,3,5-Trisubstituted Pyridinium Salts: A New Family of S. aureus Inhibitors. Molecules 2017; 22:molecules22040626. [PMID: 28417945 PMCID: PMC6153997 DOI: 10.3390/molecules22040626] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 04/07/2017] [Accepted: 04/09/2017] [Indexed: 11/16/2022] Open
Abstract
Polysubstituted pyridinium salts are valuable pharmacophores found in many biologically active molecules. Their synthesis typically involves the use of multistep procedures or harsh reaction conditions. Here, we report water-based phosphate mediated reaction conditions that promote the condensation of arylacetaldehydes with amines to give 1,3,5-pyridinium salts. The reaction, carried out at pH 6, provides conditions suitable for the use of less stable aldehydes and amines in this Chichibabin pyridine condensation. The evaluation of selected 1,3,5-trisubstituted pyridinium salts highlighted that they can inhibit the growth of S. aureus in the low μg/mL range. The synthetic accessibility of these compounds and preliminary growth inhibition data may pave the way towards the discovery of new anti-bacterials based on the 1,3,5-trisubstituted pyridinium scaffold.
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Liu K, Xu H, Xiang H, Sun P, Xie J. Protective effects of Ndfip1 on MPP(+)-induced apoptosis in MES23.5 cells and its underlying mechanisms. Exp Neurol 2015; 273:215-24. [PMID: 26300475 DOI: 10.1016/j.expneurol.2015.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 07/22/2015] [Accepted: 08/18/2015] [Indexed: 12/29/2022]
Abstract
Apoptosis has been implicated as one of the important mechanisms involved in the degeneration of dopaminergic neurons in Parkinson's disease (PD). Increasing evidence suggests that Ndfip1 is a neuroprotective protein, and Ndfip1-mediated protein ubiquitination might be a possible survival strategy in neuronal injury. The aim of the present study is to investigate the neuroprotective effect of Ndfip1 on 1-methyl-4-phenylpyridinium (MPP(+))-treated MES23.5 cells and the underlying mechanisms. Results showed that overexpression of Ndfip1 could significantly attenuate MPP(+)-induced cell loss and nuclear condensation. Further experiments demonstrated that Ndfip1 could increase Bcl-2/Bax ratio, suppress cytochrome c release from the mitochondria to cytoplasm and decrease caspase-3 activation induced by MPP(+). These results suggested that Ndfip1 protected MES23.5 cells against MPP(+) by its anti-apoptotic effect. In addition, we found that Ndfip1 overexpression could decrease the protein level of dopamine transporter (DAT). In parallel, proteasome inhibitor MG132 could markedly reverse Ndfip1-induced degradation of DAT. These data suggest that Ndfip1 exerts its inhibitory effect on DAT by modulating DAT degradation, in which ubiquitin-proteasome system activation might be involved. Collectively, our study indicated that the ability to decrease the DAT of Ndfip1 might be one of the mechanisms underlying its protective effect on MPP(+)-induced cell damage in MES23.5 cells.
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Affiliation(s)
- Kai Liu
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China
| | - Huamin Xu
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China
| | - Hengwei Xiang
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China
| | - Peng Sun
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
| | - Junxia Xie
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China.
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Liu L, Xu H, Jiang H, Wang J, Song N, Xie J. Ghrelin prevents 1-methyl-4-phenylpyridinium ion-induced cytotoxicity through antioxidation and NF-κB modulation in MES23.5 cells. Exp Neurol 2010; 222:25-9. [DOI: 10.1016/j.expneurol.2009.11.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2009] [Revised: 11/06/2009] [Accepted: 11/11/2009] [Indexed: 02/06/2023]
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Gromov SP, Fomina MV. Advances in the synthesis of 4-aryl- and 4-hetarylpyridines. RUSSIAN CHEMICAL REVIEWS 2009. [DOI: 10.1070/rc2008v077n12abeh003783] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ruan H, Yang Y, Zhu X, Wang X, Chen R. Neuroprotective effects of (±)-catechin against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurotoxicity in mice. Neurosci Lett 2009; 450:152-7. [DOI: 10.1016/j.neulet.2008.12.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 11/16/2008] [Accepted: 12/03/2008] [Indexed: 11/16/2022]
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Wimalasena DS, Perera RP, Heyen BJ, Balasooriya IS, Wimalasena K. Vesicular monoamine transporter substrate/inhibitor activity of MPTP/MPP+ derivatives: a structure-activity study. J Med Chem 2008; 51:760-8. [PMID: 18220329 DOI: 10.1021/jm070875p] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The active metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), N-methyl-4-phenylpyridinium (MPP(+)), selectively destroys the dopaminergic neurons and induces the symptoms of Parkinson's disease. Inhibition of mitochondrial complex I and/or the perturbation of dopamine metabolism through cellular and granular accumulation have been proposed as some of the major causes of neurotoxicity. In the present study we have synthesized and characterized a number of MPTP and MPP(+) derivatives that are suitable for the comparative neurotoxicity and complex I inhibition versus dopamine metabolism perturbation studies. Structure-activity studies with bovine chromaffin granule ghosts show that 3'-hydroxy-MPP(+) is one of the best known substrates for the vesicular monoamine transporter (VMAT). A series of compounds that combine the structural features of MPP(+) and a previously characterized VMAT inhibitor, 3-amino-2-phenyl-propene, have been identified as the most effective VMAT inhibitors. These derivatives have been used to define the structural requirements of the VMAT substrate and inhibitor activities.
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Sarnico I, Boroni F, Benarese M, Sigala S, Lanzillotta A, Battistin L, Spano P, Pizzi M. Activation of NF-kappaB p65/c-Rel dimer is associated with neuroprotection elicited by mGlu5 receptor agonists against MPP(+) toxicity in SK-N-SH cells. J Neural Transm (Vienna) 2007; 115:669-76. [PMID: 18094921 DOI: 10.1007/s00702-007-0007-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Accepted: 12/04/2007] [Indexed: 12/25/2022]
Abstract
Nuclear factor-kappaB (NF-kappaB) is a transcriptional regulator of neuron survival eliciting diverse effects according to the specific composition of its active dimer. While p50/p65 mediates neurodegenerative events, c-Rel-containing dimers promote cell survival. Stimulation of metabotropic glutamate receptors type 5 (mGlu5) reduces neuron vulnerability to amyloid-beta through activation of anti-apoptotic, c-Rel-dependent transcription of Bcl-X(L) pathway. We here evaluated the protective activity of mGlu5 agonists in dopaminergic SK-N-SH cells exposed to 1-methyl-4-phenylpyridinium (MPP(+)), the active metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causing parkinsonism in experimental animals. MPP(+) produced a concentration-dependent cell loss. Activation of mGlu5 receptors by CHPG (1 mM) and 3HPG (50 microM) abolished the toxic effect produced by 3 microM MPP(+). The neuroprotection was associated with activation of NF-kappaB p65/c-Rel dimer and reduction of p50/p65. These effects were prevented by the mGlu5 receptor antagonist MPEP (5 microM). It is suggested that mGlu5 receptor agonists through activation of a c-Rel-dependent anti-apoptotic pathway can rescue dopaminergic cell from mitochondrial toxicity.
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Affiliation(s)
- I Sarnico
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, Brescia, Italy
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Zhang D, Zhang JJ, Liu GT. The novel squamosamide derivative (compound FLZ) attenuated 1-methyl, 4-phenyl-pyridinium ion (MPP+)-induced apoptosis and alternations of related signal transduction in SH-SY5Y cells. Neuropharmacology 2007; 52:423-9. [PMID: 17055540 DOI: 10.1016/j.neuropharm.2006.08.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Revised: 07/27/2006] [Accepted: 08/01/2006] [Indexed: 11/24/2022]
Abstract
Compound FLZ (cFLZ) is a synthetic novel derivative of natural squamosamide. Previous pharmacological study found that cFLZ improved the abnormal behavior and the decrease of dopamine content in striatum in 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP) model mice. 1-Methyl 4-phenylpyridinium (MPP+) is the active metabolite of MPTP to cause Parkinsonism in experimental animals. The purpose of this paper was to further study the protective action of cFLZ against MPP+-induced apoptosis and alternations of related signaling transduction. The results indicated that cFLZ at concentrations of 0.1 microM and 1 microM prevented 100 microM MPP+-induced apoptosis of SH-SY5Y cells, and inhibited the release of cytochrome C and apoptosis-inducing factor (AIF), and the activation of caspase 3 and NF-kappaB as well as alpha-synuclein gene and protein expressions. The results suggest that cFLZ possesses potent neuroprotective activity and may be a potential anti-Parkinson's disease drug worthy for further study.
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Affiliation(s)
- Dan Zhang
- Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China
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Yu LB, Chen D, Li J, Ramirez J, Wang PG, Bott SG. Lanthanide-Promoted Reactions of Aldehydes and Amine Hydrochlorides in Aqueous Solution. Synthesis of 2,3-Dihydropyridinium and Pyridinium Derivatives. J Org Chem 1997; 62:208-211. [PMID: 11671385 DOI: 10.1021/jo961175n] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Li-Bing Yu
- Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
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Matsubara K, Idzu T, Kobayashi Y, Gonda T, Okunishi H, Kimura K. Differences in dopamine efflux induced by MPP+ and beta-carbolinium in the striatum of conscious rats. Eur J Pharmacol 1996; 315:145-51. [PMID: 8960877 DOI: 10.1016/s0014-2999(96)00630-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of N-methyl-4-phenylpyridinium cation (MPP+) and of an endogenously formed analog, 2,9-di-methyl-norharmanium cation (2,9-Me2NH+), on extracellular dopamine were studied in the striatum of freely moving rats. Perfusion of either 2,9-Me2NH+ or MPP+ through a microdialysis probe evoked a marked and dose-dependent increase of dopamine levels. Tetrodotoxin and Ca(2+)-free medium prevented the increase in dopamine levels induced by 2,9-Me2NH+, but not that induced by MPP+. Cocaine, 3 microM, intensified the 2,9-Me2 NH(+)-induced increase in extracellular dopamine and slightly attenuated the MPP(+)-induced efflux. S(-)-3-(3-Hydroxy-phenyl)-N-propylpiperidine, that acts as an antagonist of dopamine autoreceptors in the presence of a dopamine reuptake inhibitor, markedly enhanced the increase in extracellular dopamine elicited by 2,9-Me2NH+, but not that by MPP+. These results suggested that 2,9-Me2NH+ was a potent dopamine reuptake blocker, whereas MPP+ acts as an amphetamine-like dopamine releaser rather than a reuptake inhibitor on the membrane transporter.
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Affiliation(s)
- K Matsubara
- Department of Legal Medicine, Shimane Medical University, Izumo, Japan
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McNaught KS, Thull U, Carrupt PA, Altomare C, Cellamare S, Carotti A, Testa B, Jenner P, Marsden CD. Inhibition of [3H]dopamine uptake into striatal synaptosomes by isoquinoline derivatives structurally related to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Biochem Pharmacol 1996; 52:29-34. [PMID: 8678905 DOI: 10.1016/0006-2952(96)00133-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Isoquinoline derivatives structurally related to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 1-methyl-4-phenylpyridinium (MPP+) may be endogenous neurotoxins causing nigral cell death in Parkinson's disease. These compounds inhibit mitochondrial function but, like MPP+, require accumulation in dopaminergic neurones via the dopamine reuptake system to exert toxicity. We, now, examine the substrate affinity of 14 neutral and quaternary isoquinoline derivatives (7 isoquinolines, 2 dihydroisoquinolines and 5 1,2,3,4-tetrahydroisoquinolines) for the dopamine reuptake system by their ability to inhibit the uptake of [3H]dopamine into rat striatal synaptosomes. Ten isoquinoline derivatives and MPP+ inhibited [3H]dopamine uptake in a concentration-dependent manner. Only 5 isoquinoline derivatives produced 50% inhibition of [3H]dopamine uptake (IC50 = 8.0-50.0 microM), none of which were as potent as MPP+ (IC50 = 0.33 microM). These findings suggest that isoquinoline derivatives are moderate to poor substrates for the dopamine reuptake system and that high concentrations of, or prolonged exposure to, isoquinoline derivatives may be necessary to cause neurodegeneration.
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Affiliation(s)
- K S McNaught
- Neurodegenerative Diseases Research Centre, King's College, London, UK
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Cobuzzi RJ, Neafsey EJ, Collins MA. Differential cytotoxicities of N-methyl-beta-carbolinium analogues of MPP+ in PC12 cells: insights into potential neurotoxicants in Parkinson's disease. J Neurochem 1994; 62:1503-10. [PMID: 8133278 DOI: 10.1046/j.1471-4159.1994.62041503.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
N-Methylated beta-carbolinium cations that can form in vivo from environmental or endogenous beta-carbolines are putative neurotoxic factors in Parkinson's disease. The cytotoxicities of 11 N-methylated beta-carbolinium cations and N-methyl-4-phenylpyridinium cation (MPP+), the experimental parkinsonian neurotoxicant which the carbolinium cations structurally resemble, were examined using rat pheochromocytoma (PC12) cells cultured in "low energy" N-5 medium; cell death was estimated by released lactate dehydrogenase activity and viable cell protein. Of the eight N2-monomethylated beta-carbolinium cations utilized, only 2-methyl-harmalinium (harmaline-2-methiodide) was as cytotoxic as MPP+. Also, three N2(beta), N9(indole)-dimethylated beta-carbolinium cations displayed cytotoxic effects, with the simplest, 2,9-dimethylnorharmanium, approaching the effectiveness of MPP+ in PC12 cells cultured in N-5 medium. However, when PC12 cells grown in higher energy Dulbecco's modified Eagle's medium were utilized with selected effective cations, it was observed that the cultures were relatively resistant to MPP+ and 2,9-dimethylnorharmanium, but remained vulnerable to 2-methylharmalinium. The results are interpreted to mean that different cytotoxic mechanisms exist for the two most potent beta-carbolinium cations--namely, a mechanism for the 2,9-dimethyl-beta-carbolinium species that, as with MPP+, is conditional on mitochondrial ATP depletion, but a different (or additional) mechanism for 2-methylharmalinium that is independent of mitochondrial inhibition. The possible accumulation of these cytotoxic cations in Parkinson's disease is discussed in the context of these findings.
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Affiliation(s)
- R J Cobuzzi
- Department of Molecular and Cellular Biochemistry, Loyola University Stritch School of Medicine, Maywood, Illinois
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Liptrot J, Holdup D, Phillipson O. 1,2,3,4-Tetrahydro-2-methyl-4,6,7-isoquinolinetriol depletes catecholamines in rat brain. J Neurochem 1993; 61:2199-206. [PMID: 7504086 DOI: 10.1111/j.1471-4159.1993.tb07460.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
1,2,3,4-Tetrahydro-2-methyl-4,6,7-isoquinolinetriol (TMIQ) was synthesised and tested for activity as a dopamine-depleting agent in rat brain. After intracerebroventricular infusion, TMIQ caused reductions in dopamine concentrations in substantia nigra, striatum, hypothalamus, and dorsal raphe, and reduction in noradrenaline concentrations in locus coeruleus. TMIQ also reduced 5-hydroxytryptamine concentrations in dorsal raphe and substantia nigra, although with a lower potency. Comparisons between TMIQ and MPTP showed that they were approximately equipotent in depleting dopamine in the substantia nigra, hypothalamus, and dorsal raphe. Pretreatment of animals with a combination of monoamine oxidase A and B inhibitors completely prevented the TMIQ-induced reductions in dopamine concentrations in substantia nigra and hypothalamus. Direct unilateral intrastriatal injections of TMIQ produced marked ipsilateral reductions in striatal dopamine, correlating with a behavioural response consisting of turning towards the side of injection. The results suggest that TMIQ should be evaluated further as a possible MPTP-like compound, which may derive from endogenous beta-hydroxylated catecholamines.
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Affiliation(s)
- J Liptrot
- Department of Anatomy, School of Medical Sciences, University of Bristol, England
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Matsubara K, Collins MA, Akane A, Ikebuchi J, Neafsey EJ, Kagawa M, Shiono H. Potential bioactivated neurotoxicants, N-methylated beta-carbolinium ions, are present in human brain. Brain Res 1993; 610:90-6. [PMID: 8518935 DOI: 10.1016/0006-8993(93)91221-d] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Potential bioactivated neurotoxicants, 2-N-methyl-beta-carbolinium and 2,9-N,N'-dimethyl-beta-carbolinium ions, as well as N-methylation activities which form these charged species, were analyzed for the first time in the parietal association cortex and the substantia nigra of human brain using GC/MS and HPLC. The brains were taken during forensic autopsies from corpses without obvious degeneration of substantia nigra. In the cortex, 2-methyl-norharmanium ion (2-MeNH) and 2,9-dimethyl-norharmanium ion (2,9-Me2NH) were detected in almost all samples. 2-Methyl-harmanium ions (2-MeHA) and 2,9-dimethyl-harmanium ions (2,9-Me2HA) were detectable in only two samples. In substantia nigra samples pooled from 3 or 4 brains for analysis, 2-MeNH and 2,9-Me2NH levels were higher than those in the cortex, whereas 2-MeHA and 2,9-Me2HA were below detection limits. Their precursors, norharman (NH) and harman (HA), were also measured using HPLC/fluorescence detection. In both regions, NH and HA were present in almost all samples; levels of NH and HA were also significantly higher in the nigra than in the cortex. Using 9-methyl-NH and 2-MeNH as substrates, in vitro N-methylation of the 2[beta] and 9[indole] nitrogens toward beta-carbolines was measured both in the cortex and in the nigra. 2[beta]-N-Methylation activity was significantly higher than 9[indole]-N-methylation activity in both regions. Recent studies show that beta-carbolinium ions resemble the synthetic parkinsonian toxicant, MPP+, with respect to structure and neurotoxic activity. Such 'bioactivated' carbolinium ions could be endogenous causative factors in Parkinson's disease.
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Affiliation(s)
- K Matsubara
- Department of Legal Medicine, Shimane Medical University, Izumo, Japan
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Matsubara K, Neafsey EJ, Collins MA. Novel S-adenosylmethionine-dependent indole-N-methylation of beta-carbolines in brain particulate fractions. J Neurochem 1992; 59:511-8. [PMID: 1629724 DOI: 10.1111/j.1471-4159.1992.tb09400.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Guinea pig brain S-adenosylmethionine (SAM)-dependent N-methyltransferase activity toward physiologically relevant beta-carboline (BC) substrates was examined with reverse-phase HPLC and radiochemical detection. Representative BCs, norharman and harmine, were enzymatically methylated on the 2[beta]-nitrogen by [3H]CH3-SAM in undialyzed homogenates to yield 2[beta]-methylated BCs and subsequently on the 9[indole]-nitrogen to generate 2,9-dimethylated BC products. This may be the first account of mammalian indole N-methyl transfer. There was no HPLC evidence for 9-methyl BC or (from carbon methylation) 2,6-dimethyl BC products. Capillary gas chromatography-mass spectrometry analysis confirmed the structures of the 2,9-dimethyl and 2-methyl products of norharman. The 2[beta]- and 9[indole]-N-methylation activities were mainly in the nuclear fractions and were negligible in undialyzed cytosol. This differs from the cytosolic SAM-dependent N-methylations reported with other azaheterocyclics, including 1,2,3,4-tetrahydro-BCs. The involvement of a single enzyme was suggested because the two N-methyl transfers with BC substrate had similar subcellular activity patterns, regional brain distributions, and Km and Vmax values. Sequential N-methylation of various BCs that have been observed in vivo may be a unique route to centrally retained N2,N9-dimethylated beta-carbolinium ions. Because they resemble the synthetic parkinsonian toxicant, N-methyl-4-phenylpyridinium, with respect to structure and neurotoxic activity, such "bioactivated" carbolinium ions could be endogenous causative factors in Parkinson's disease.
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Affiliation(s)
- K Matsubara
- Department of Molecular and Cellular Biochemistry, Loyola University of Chicago Stritch School of Medicine, Maywood, Illinois 60153
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Mitsumoto A, Nagano T, Hirobe M. Toxicity of 1-methyl-4-phenylpyridinium derivatives in Escherichia coli. Arch Biochem Biophys 1992; 296:482-8. [PMID: 1321585 DOI: 10.1016/0003-9861(92)90601-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Several derivatives of 1-methyl-4-phenylpyridinium (MPP+), i.e., 1-methyl-4-(4'-nitrophenyl)pyridinium (1), 1-methyl-4-(4'-cyanophenyl)pyridinium (2), 1-methyl-4-(3'-nitrophenyl)pyridinium (3), 1-methyl-4-(4'-chlorophenyl)pyridinium (4), 1-methyl-4-(4'-acetamidophenyl)pyridinium (5), and 1-methyl-4-(4'-aminophenyl)pyridinium (6), were synthesized in order to compare their toxicity with that of paraquat (PQ2+) in Escherichia coli. Addition of compounds 1, 2, and 3 to aerobic E. coli cell suspensions caused extracellular ferricytochrome c reduction, which was inhibited by superoxide dismutase in the same manner as that in the case of PQ2+. The rate of the ferricytochrome c (cyt. c) reduction was in the order of PQ2+ greater than 1 greater than 2 greater than 3, which is the same as that of the redox potentials of these compounds. On the other hand, MPP+, 4, 5, and 6, which have more negative potentials, had no effect on the cyt. c reduction. Compound 1 inhibited the growth of E. coli under aerobic conditions, but not under anaerobic conditions. The results show that compound 1 can act as a mediator for production of superoxide (O2-.), which seriously injures E. coli cells. However, though compounds 2 and 3 catalyzed the production of O2-. in E. coli cells, their activity of O2-. production was much lower than that of compound 1 or PQ2+. Thus, compound 3 had no effect on growth or survival of E. coli at 1 mM, while compounds 2 and 4 had both bacteriostatic and bacteriocidal effects which were independent of dioxygen (O2). The results show that the toxic mechanism is different from that of compound 1. MPP+, 5, and 6 had no effect on growth of E. coli. This paper shows that compound 1 is a novel enhancer of intracellular superoxide production, though the mechanism of toxicity of compounds 2 and 4 is not clear yet. The results suggest that the redox potential is a crucial factor for manifestation of the activity.
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Affiliation(s)
- A Mitsumoto
- Faculty of Pharmaceutical Sciences, University of Tokyo, Japan
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Abstract
The present study has examined the effects of systemically administered MPTP and MPP+ upon striatal DA and Dopac of C57 mice, also treated concurrently with either saline or reserpine. MPTP followed by saline did not affect DA level but decreased that of Dopac only at 5.0 mg/kg and higher dosages. The potency of MPTP affecting DA increased greatly when the neurotoxicant was followed by either 5.0 or 10.0 mg/kg reserpine; MPTP at 0.10 mg/kg and higher dosages significantly reversed the DA depleting effects of reserpine. MPP+ (1.0 or 10.0 mg/kg) with saline did not affect either DA or Dopac. In contrast, MPP+ at 0.10 mg/kg and higher dosages, when followed by 10.0 mg/kg reserpine, dose-dependently enhanced the DA depleting effects of reserpine. In agreement with the earlier results obtained in vitro, the present study indicates that MPTP administration at trace level dosages may lead to an inhibition of MAO in vivo. The effect of systemically given MPP+ on DA, however, appears to be more complex in nature, conceivably comprised of actions at the striatal neurones including the intraneuronal vesicles and, possibly, at the substantia nigra which may affect striatum in turn. That MPP+ may have reached brain areas in these experiments is also indicated by the observation of a significant striatal level of 3H-MPP+ after its systemic administration. In conclusion, irrespective of MPTP and MPP+ action mechanisms, trace levels of these neurotoxicants appear to affect brain dopamine neurons.
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Affiliation(s)
- S P Bagchi
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York 10962
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Gerlach M, Riederer P, Przuntek H, Youdim MB. MPTP mechanisms of neurotoxicity and their implications for Parkinson's disease. Eur J Pharmacol 1991; 208:273-86. [PMID: 1815982 DOI: 10.1016/0922-4106(91)90073-q] [Citation(s) in RCA: 238] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) gives rise to motor deficits in humans and other primates which closely resemble those seen in patients with Parkinson's disease. These deficits are associated with a relatively selective loss of cells in the pars compacta of the substantia nigra and severe reductions in the concentrations of dopamine, noradrenaline and serotonin in the striatum. Similarly, in mice of various different strains the administration of MPTP also induces a marked loss of dopaminergic cells with severe depletion of biogenic amines, but higher doses of MPTP are required to produce these effects in mice than in primates. This review summarises advances made in understanding the biochemical events which underlie the remarkable neurotoxic action of MPTP. Major steps in the expression of neurotoxicity involve the conversion of MPTP to the toxic agent 1-methyl-4-phenylpyridinium ion (MPP+) by type B monoamine oxidase (MAO-B) in the glia, specific uptake of MPP+ into the nigro-striatal dopaminergic neurones, the intraneuronal accumulation of MPP+, and the neurotoxic action of MPP+. This is exerted mainly through the inhibition of the enzymes of the respiratory chain (Complex I), the disturbance of Ca2+ homeostasis, and possibly by the formation of free radicals. The relevance of the MPTP model to idiopathic Parkinson's disease is discussed.
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Affiliation(s)
- M Gerlach
- Department of Psychiatry, University of Würzburg, F.R.G
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Sayre LM, Wang FJ, Arora PK, Riachi NJ, Harik SI, Hoppel CL. Dopaminergic neurotoxicity in vivo and inhibition of mitochondrial respiration in vitro by possible endogenous pyridinium-like substances. J Neurochem 1991; 57:2106-15. [PMID: 1940917 DOI: 10.1111/j.1471-4159.1991.tb06429.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Elucidation of the mechanism(s) by which 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP) and its active metabolite 1-methyl-4-phenylpyridinium (MPP+) cause parkinsonism in humans and other primates has prompted consideration of possible endogenous MPTP/MPP(+)-like neurotoxins in the etiology of idiopathic Parkinson's disease. Here we examined inhibition of mitochondrial respiration in vitro and neurotoxicity in rats in vivo produced by beta-carbolinium compounds that are presumed to form following Pictet-Spengler cyclization of serotonin. We also evaluated N-methylisoquinolinium, a putative endogenous neurotoxin, in the same manner. The latter compound exhibited MPP(+)-like mitochondrial respiratory inhibition, whereas the beta-carbolinium compounds, although more potent inhibitors of electron transport, exhibited weak accumulation-dependent enhancement of inhibition in intact mitochondria. It is interesting that the beta-carbolinium compounds inhibited succinate- as well as glutamate-supported respiration, and are best described as inhibitor-uncouplers. The results of partitioning experiments suggest that both the low accumulation potential and the inhibition of succinate respiration may be a consequence of the beta-carboliniums being in equilibrium with neutral "anhydro" bases. Relative to MPP+, all compounds tested had weak dopaminergic uptake activity in vitro and weak dopaminergic toxicity in vivo, consistent with other findings of relatively low neurotoxic potential for presumed endogenous pyridiniums.
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Affiliation(s)
- L M Sayre
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
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Hara S, Endo T, Kuriiwa F, Kano S. Effects of MPTP, MPP+, and paraquat on NADPH-dependent lipid peroxidation in mouse brain and lung microsomes. BIOCHEMICAL MEDICINE AND METABOLIC BIOLOGY 1991; 45:292-7. [PMID: 1904747 DOI: 10.1016/0885-4505(91)90033-h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Both MPTP and MPP+ inhibited the NADPH-dependent microsomal LPO in mouse brain and lung. On the other hand, PQ significantly stimulated the LPO in brain microsomes in a dose-dependent manner. The herbicide, however, stimulated lung microsomal LPO only in a narrow concentration range, despite much higher P450 reductase activity in lung microsomes than that in brain microsomes. These findings suggest that the effect of PQ on microsomal LPO is different from those of the analogous neurotoxins, MPTP and MPP+, and is not uniform in brain and lung.
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Affiliation(s)
- S Hara
- Department of Forensic Medicine, Tokyo Medical College, Japan
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Albores R, Neafsey EJ, Drucker G, Fields JZ, Collins MA. Mitochondrial respiratory inhibition by N-methylated beta-carboline derivatives structurally resembling N-methyl-4-phenylpyridine. Proc Natl Acad Sci U S A 1990; 87:9368-72. [PMID: 2251279 PMCID: PMC55166 DOI: 10.1073/pnas.87.23.9368] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mitochondrial accumulation and respiratory inhibition are critical steps in the actions of N-methyl-4-phenylpyridinium ion (MPP+), the toxic metabolite of the parkinsonism-inducing agent, N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. We examined the respiratory characteristics of 2-methylated beta-carbolines (2-Me beta Cs) and 2-methylated 3,4-dihydro-beta-carbolines (2-MeDH beta Cs), which encompass the MPP+ structure. As indoleamine derivatives, they could have endogenous roles in idiopathic parkinsonism. With rat liver mitochondria, the order for inhibition of NAD(+)-linked O2 consumption (6-min preincubations) was as follows: MPP+ = 2-methylharmine greater than 2-methylharmol = 2-methylharmaline much greater than 2-methylharmalol greater than 2-methylnorharman greater than 6-OH-2-methylharmalan much greater than 2-methylharman. Similar to MPP+, 2-MeDH beta C/2-Me beta C inhibition was potentiated by tetraphenylboron and reversed by dinitrophenol, consistent with the involvement of cationic forms. However, the participation of neutral forms was indicated by the 2-MeDH beta C/2-Me beta C inhibitory time courses, which were unlike MPP+. The neutral forms probably arise via indolic nitrogen deprotonation because the characteristics of a cationic beta-carboline that cannot N-deprotonate, 2,9-dimethylnorharman, mirrored MPP+ rather than 2-Me beta Cs. Succinate-supported respiration was also significantly blocked by 2-MeDH beta Cs/2-Me beta Cs, but results with tetraphenylboron and 2,9-dimethylnorharman indicated that cationic forms were less important than in the inhibition of NAD(+)-linked respiration. We suggest that the relatively potent inhibition by certain 2-MeDH beta Cs/2-Me beta Cs involves neutral forms for passive mitochondrial entry and cationic as well as neutral forms that act at several respiratory sites. Respiratory inhibition could reasonably underlie the reported neurotoxicity of 2-Me beta Cs.
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Affiliation(s)
- R Albores
- Department of Molecular, Loyola University Stritch School of Medicine, Maywood, IL 60153
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Youngster SK, Gluck MR, Heikkila RE, Nicklas WJ. 4'-alkylated analogs of 1-methyl-4-phenylpyridinium ion are potent inhibitors of mitochondrial respiration. Biochem Biophys Res Commun 1990; 169:758-64. [PMID: 2357232 DOI: 10.1016/0006-291x(90)90396-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
1-Methyl-4-phenylpyridinium ion, a major brain metabolite of the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, is an inhibitor of Complex I of the mitochondrial respiratory chain. We have synthesized several analogs of 1-methyl-4-phenylpyridinium ion containing various alkyl groups in the 4' position of the phenyl ring and have tested them for their abilities to inhibit the oxidation of NADH-linked substrates by intact mouse liver mitochondria. These compounds are considerably more potent inhibitors than MPP+ itself, with potency increasing as the length of the alkyl chain increases. The most potent inhibitor, 1-methyl-4-(4'heptylphenyl)pyridinium ion, was about 200 times as effective as MPP+. These analogs should prove to be useful tools for studying the nature of the process whereby MPP+ and its pyridinium analogs interact with Complex I to inhibit mitochondrial respiration.
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Affiliation(s)
- S K Youngster
- Department of Neurology, UMDNJ-Robert Wood Johnson Medical School, Piscataway 08854
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