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Amoateng P, Tagoe TA, Karikari TK, Kukuia KKE, Osei-Safo D, Woode E, Frenguelli BG, Kombian SB. Synedrella nodiflora Extract Depresses Excitatory Synaptic Transmission and Chemically-Induced In Vitro Seizures in the Rat Hippocampus. Front Pharmacol 2021; 12:610025. [PMID: 33762938 PMCID: PMC7982396 DOI: 10.3389/fphar.2021.610025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/07/2021] [Indexed: 01/14/2023] Open
Abstract
Extracts of the tropical Cinderella plant Synedrella nodiflora are used traditionally to manage convulsive conditions in the West African sub-region. This study sought to determine the neuronal basis of the effectiveness of these plant extracts to suppress seizure activity. Using the hippocampal slice preparation from rats, the ability of the extract to depress excitatory synaptic transmission and in vitro seizure activity were investigated. Bath perfusion of the hydro-ethanolic extract of Synedrella nodiflora (SNE) caused a concentration-dependent depression of evoked field excitatory postsynaptic potentials (fEPSPs) recorded extracellularly in the CA1 region of the hippocampus with maximal depression of about 80% and an estimated IC50 of 0.06 mg/ml. The SNE-induced fEPSP depression was accompanied by an increase in paired pulse facilitation. The fEPSP depression only recovered partially after 20 min washing out. The effect of SNE was not stimulus dependent as it was present even in the absence of synaptic stimulation. Furthermore, it did not show desensitization as repeat application after 10 min washout produced the same level of fEPSP depression as the first application. The SNE effect on fEPSPs was not via adenosine release as it was neither blocked nor reversed by 8-CPT, an adenosine A1 receptor antagonist. In addition, SNE depressed in vitro seizures induced by zero Mg2+ and high K+ -containing artificial cerebrospinal fluid (aCSF) in a concentration-dependent manner. The results show that SNE depresses fEPSPs and spontaneous bursting activity in hippocampal neurons that may underlie its ability to abort convulsive activity in persons with epilepsy.
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Affiliation(s)
- Patrick Amoateng
- Department of Pharmacology and Toxicology, School of Pharmacy, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Thomas A Tagoe
- Department of Physiology, UG Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Thomas K Karikari
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Kennedy K E Kukuia
- Department of Medical Pharmacology, UG Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Dorcas Osei-Safo
- Department of Chemistry, School of Physical and Mathematical Sciences, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana
| | - Eric Woode
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Health and Allied Sciences, Ho, Ghana
| | - Bruno G Frenguelli
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Samuel B Kombian
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Health Science Center, Kuwait University, Safat, Kuwait.,Department of Pharmacology and Toxicology, School of Medicine and Medical Sciences, University for Development Studies, Tamale, Ghana
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Eremina JA, Lider EV, Sukhikh TS, Eltsov IV, Kuratieva NV, Zakharov BA, Sheludyakova LA, Klyushova LS, Ermakova EA, Dotsenko VV. Synthesis, crystal structures, spectroscopic, and cytotoxicity study of Cu(II), Co(II), Ni(II) and Pd(II) complexes with 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione. Polyhedron 2020. [DOI: 10.1016/j.poly.2019.114325] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Khajah MA, Ananthalakshmi KV, Edafiogho I. Anti-Inflammatory Properties of the Enaminone E121 in the Dextran Sulfate Sodium (DSS) Colitis Model. PLoS One 2016; 11:e0168567. [PMID: 27997590 PMCID: PMC5173236 DOI: 10.1371/journal.pone.0168567] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 12/03/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Enaminones are synthetic compounds with an established role in the prevention of various forms of seizures. Recent evidence suggests potent anti-tussive, bronchodilation and anti-inflammatory properties. Pre-treatment with particularly E121 compound resulted in a decrease in leukocyte recruitment in the ovalbumin induced-model of asthma, immune cell proliferation and cytokine release in vitro. We hypothesize that E121 might serve as a therapeutic potential in intestinal inflammation through modulating immune cell functions. METHODS Colitis was induced by daily dextran sulfate sodium (DSS) administration for 5 days, and its severity was determined by gross and histological assessments. The plasma level of various cytokines was measured using flow cytometry-based assay. The colonic expression/ phosphorylation level of various molecules was determined by immunofluorescence and western blotting. The effects of E121 treatment on in vitro neutrophil chemotaxis (under-agarose assay), superoxide release (luminol oxidation assay) and apoptosis (annexin V/7AAD) were also determined. RESULTS DSS-induced colitis in mice was significantly reduced by daily E121 treatment (30-100 mg/kg) at gross and histological levels. This effect was due to modulated plasma levels of interleukin (IL-2) and colonic expression levels of various signaling molecules and proteins involved in apoptosis. In vitro neutrophil survival, chemotaxis, and superoxide release were also reduced by E121 treatment. CONCLUSION Our results indicate important anti-inflammatory actions of E121 in the pathogenesis of IBD.
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Affiliation(s)
| | | | - Ivan Edafiogho
- Department of Pharmaceutical Sciences, University of Saint Joseph School of Pharmacy, Hartford, Connecticut, United States of America
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Allosteric Modulation of GABAA Receptors by an Anilino Enaminone in an Olfactory Center of the Mouse Brain. Pharmaceuticals (Basel) 2014; 7:1069-90. [PMID: 25525715 PMCID: PMC4276907 DOI: 10.3390/ph7121069] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 11/24/2014] [Accepted: 12/04/2014] [Indexed: 12/28/2022] Open
Abstract
In an ongoing effort to identify novel drugs that can be used as neurotherapeutic compounds, we have focused on anilino enaminones as potential anticonvulsant agents. Enaminones are organic compounds containing a conjugated system of an amine, an alkene and a ketone. Here, we review the effects of a small library of anilino enaminones on neuronal activity. Our experimental approach employs an olfactory bulb brain slice preparation using whole-cell patch-clamp recording from mitral cells in the main olfactory bulb. The main olfactory bulb is a key integrative center in the olfactory pathway. Mitral cells are the principal output neurons of the main olfactory bulb, receiving olfactory receptor neuron input at their dendrites within glomeruli, and projecting glutamatergic axons through the lateral olfactory tract to the olfactory cortex. The compounds tested are known to be effective in attenuating pentylenetetrazol (PTZ) induced convulsions in rodent models. One compound in particular, KRS-5Me-4-OCF3, evokes potent inhibition of mitral cell activity. Experiments aimed at understanding the cellular mechanism underlying the inhibitory effect revealed that KRS-5Me-4-OCF3 shifts the concentration-response curve for GABA to the left. KRS-5Me-4-OCF3 enhances GABA affinity and acts as a positive allosteric modulator of GABAA receptors. Application of a benzodiazepine site antagonist blocks the effect of KRS-5Me-4-OCF3 indicating that KRS-5Me-4-OCF3 binds at the classical benzodiazepine site to exert its pharmacological action. This anilino enaminone KRS-5Me-4-OCF3 emerges as a candidate for clinical use as an anticonvulsant agent in the battle against epileptic seizures.
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Qaddoumi MG, Ananthalakshmi KVV, Phillips OA, Edafiogho IO, Kombian SB. Evaluation of anticonvulsant actions of dibromophenyl enaminones using in vitro and in vivo seizure models. PLoS One 2014; 9:e99770. [PMID: 24945912 PMCID: PMC4063795 DOI: 10.1371/journal.pone.0099770] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 05/15/2014] [Indexed: 12/16/2022] Open
Abstract
Epilepsy and other seizure disorders are not adequately managed with currently available drugs. We recently synthesized a series of dibromophenyl enaminones and demonstrated that AK6 and E249 were equipotent to previous analogs but more efficacious in suppressing neuronal excitation. Here we examined the actions of these lead compounds on in vitro and in vivo seizure models. In vitro seizures were induced in the hippocampal slice chemically (zero Mg2+ buffer and picrotoxin) and electrically using patterned high frequency stimulation (HFS) of afferents. In vivo seizures were induced in rats using the 6 Hz and the maximal electroshock models. AK6 (10 µM) and E249 (10 µM) depressed the amplitude of population spikes recorded in area CA1 of the hippocampus by -50.5±4.3% and -40.1±3.1% respectively, with partial recovery after washout. In the zero Mg2+ model, AK6 (10 µM) depressed multiple population spiking (mPS) by -59.3±6.9% and spontaneous bursts (SBs) by -65.9±7.2% and in the picrotoxin-model by -43.3±7.2% and -50.0±8.3%, respectively. Likewise, E249 (10 µM) depressed the zero-Mg2+-induced mPS by -48.8±9.5% and SBs by -55.8±15.5%, and in the picrotoxin model by -37.1±5.5% and -56.5±11.4%, respectively. They both suppressed post-HFS induced afterdischarges and SBs. AK6 and E249 dose-dependently protected rats in maximal electroshock and 6 Hz models of in vivo seizures after 30 min pretreatment. Their level of protection in both models was similar to that obtained with phenytoin Finally, while AK6 had no effect on locomotion in rats, phenytoin significantly decreased locomotion. AK6 and E249, suppressed in vitro and in vivo seizures to a similar extent. Their in vivo activities are comparable with but not superior to phenytoin. The most efficacious, AK6 produced no locomotor suppression while phenytoin did. Thus, AK6 and E249 may be excellent candidates for further investigation as potential agents for the treatment of epilepsy syndromes with possibly less CNS side effects.
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Affiliation(s)
- Mohamed G. Qaddoumi
- Department of Pharmacology & Therapeutics, Faculty of Pharmacy, Kuwait University, Safat, Kuwait
| | | | - Oludotun A. Phillips
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Kuwait University, Safat, Kuwait
| | - Ivan O. Edafiogho
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Saint Joseph, Hartford, Connecticut, United States of America
| | - Samuel B. Kombian
- Department of Pharmacology & Therapeutics, Faculty of Pharmacy, Kuwait University, Safat, Kuwait
- * E-mail:
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Synthesis, neuronal activity and mechanisms of action of halogenated enaminones. Eur J Med Chem 2014; 76:20-30. [DOI: 10.1016/j.ejmech.2014.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 01/22/2014] [Accepted: 02/03/2014] [Indexed: 11/23/2022]
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The anticonvulsant enaminone E139 attenuates paclitaxel-induced neuropathic pain in rodents. ScientificWorldJournal 2013; 2013:240508. [PMID: 24385872 PMCID: PMC3872104 DOI: 10.1155/2013/240508] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 11/20/2013] [Indexed: 11/30/2022] Open
Abstract
The enaminone methyl 4-(4′-bromophenyl)aminocyclohex-3-en-6-methyl-2-oxo-1-oate (E139) has anticonvulsant activities. It has been reported to have a better safety profile than some anticonvulsant drugs. Since some anticonvulsant drugs are used in the management of neuropathic pain, we evaluated the effects of E139 in rodent models of acute pain and paclitaxel-induced neuropathic pain. The reaction latency to thermal stimuli (hot-plate test) of BALB/c mice was recorded before and after intraperitoneal treatment with paclitaxel (2 mg/kg, i.p. for 5 consecutive days), and after treatment with E139 (0.1–40 mg/kg), amitriptyline (10 mg/kg), and gabapentin (10 and 30 mg/kg). Mechanical allodynia in paclitaxel-treated Sprague Dawley (SD) rats was measured using a dynamic plantar aesthesiometer before and after treatment with E139 (10 and 20 mg/kg) or its vehicle for four consecutive days from day 7 after first administration of paclitaxel (16 mg/kg on two alternate days). Administration of E139 (10–40 mg/kg) produced antinociceptive activity against thermal nociception in naïve mice. Treatment with E139, amitriptyline, or gabapentin reduced paclitaxel-induced thermal hyperalgesia. E139 reduced paclitaxel-induced mechanical allodynia, with the effects lasting longer (24 h) after repetitive dosing. Our results indicate that E139 has antinociceptive activity and attenuates paclitaxel-induced neuropathic pain in rodents.
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Kombian SB, Phillips OA. Novel actions of oxazolidinones: in vitro screening of a triazolyloxazolidinone for anticonvulsant activity. Med Princ Pract 2013; 22:340-5. [PMID: 23257573 PMCID: PMC5586748 DOI: 10.1159/000346005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 11/21/2012] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To test the hypothesis that a triazolyloxazolidinone (PH084) has anticonvulsant activity by examining its effects on in vitro seizure models in the rat hippocampus. MATERIALS AND METHODS Whole-cell synaptic currents, action potentials and extracellular population spikes (PS) were recorded in the cell body area of rat hippocampal CA1 region in acutely prepared slices. Chemical [picrotoxin (100 µM) and zero magnesium] and electrical seizures were induced and the effect of PH084 (10 µM) was tested on cellular responses, multiple spikes and spontaneous bursting frequencies. RESULTS PH084 depressed evoked excitatory postsynaptic currents, action potential firing frequency and PS amplitude. All of these responses did not recover to baseline after 15-20 min washout of PH084. Perfusion with zero magnesium ion (Mg(2+))-containing buffer converted a single PS to multiple PS (mPS) accompanied by spontaneous burst. PH084 suppressed the mPS and the spontaneous burst frequency and it also suppressed the picrotoxin-induced mPS number. However, it did not affect the frequency of stimulus train-induced after discharge or bursts. Furthermore, 8-10 min pretreatment with PH084 did not affect the ability of zero Mg(2+) buffer, picrotoxin or stimulus train to induce epileptiform activity. CONCLUSIONS Thus, while PH084 may have potential for anticonvulsant activity against chemically induced seizures, it has little or no potential against electrically induced seizures or in preventing epileptiform discharge.
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Affiliation(s)
- Samuel B Kombian
- Department of Pharmacology and Therapeutics Faculty of Pharmacy, Kuwait University, Safat, Kuwait.
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Glotova TE, Dvorko MY, Ushakov IA, Shabalin DA, Schmidt EY, Trofimov BA. Modification of g-Aminobutyric Acid with Acylacetylenes: Stereoselective C-Vinylation of the Primary Adducts and Transformation to Acylpyridines. MENDELEEV COMMUNICATIONS 2012. [DOI: 10.1016/j.mencom.2012.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Nashawi H, Bartl T, Bartl P, Novotny L, Oriowo M, Kombian S. TH-9 (a theophylline derivative) induces long-lasting enhancement in excitatory synaptic transmission in the rat hippocampus that is occluded by frequency-dependent plasticity in vitro. Neuroscience 2012; 220:70-84. [DOI: 10.1016/j.neuroscience.2012.06.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 06/10/2012] [Accepted: 06/11/2012] [Indexed: 11/24/2022]
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Jiang B, Wang X, Li MY, Wu Q, Ye Q, Xu HW, Tu SJ. A domino synthetic strategy leading to two-carbon-tethered fused acridine/indole pairs and fused acridine derivatives. Org Biomol Chem 2012; 10:8533-8. [DOI: 10.1039/c2ob26315g] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Chikhalikar S, Bhawe V, Jachak M, Ghagare M. Synthesis of Pyridin-2(1H)-one Derivatives: Temperature-Dependent Selectivity. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100800] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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El-Hashim AZ, Edafiogho IO, Jaffal SM, Yousif MH, Ezeamuzie CI, Kombian SB. Anti-tussive and bronchodilator mechanisms of action for the enaminone E121. Life Sci 2011; 89:378-87. [PMID: 21798272 DOI: 10.1016/j.lfs.2011.07.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2010] [Revised: 06/23/2011] [Accepted: 07/07/2011] [Indexed: 11/27/2022]
Abstract
AIMS In this study, we investigated whether the enaminone, E121, has anti-tussive effects in a guinea pig model of cough, and if so, whether this effect is mediated via a central or peripheral site of action. We also assessed whether E121 has bronchodilator effects and the molecular mechanisms underlying any anti-tussive and/or bronchodilator effects. MAIN METHODS Whole body plethysmography was used to assess both cough and airway obstruction. A stereotaxic apparatus was used to administer drugs intracerebroventricularly (i.c.v.). Effects of E121 were examined in vitro on contractile effects in guinea pig bronchioles. KEY FINDINGS Pre-treatment of animals with E121 resulted in a significant inhibition in the citric acid-induced cough and airway obstruction compared to vehicle-pretreated animals. The K(ATP) antagonist, glibenclamide, significantly inhibited the anti-tussive and bronchoprotective effects of E121. Also, intra-tracheal administration of E121 resulted in a significant inhibition of both the citric acid-induced cough response and airway obstruction compared to vehicle-pretreated animals. By contrast, i.c.v. administration had no effect. Finally, E121 significantly inhibited carbachol-induced airway smooth muscle contractions, an effect that was reduced by both glibenclamide and propranolol. Interestingly, E121 enhanced histamine-induced cAMP release in human eosinophils although it did not directly elevate cAMP levels. SIGNIFICANCE The enaminone, E121, has anti-tussive and bronchodilatory effects and is topically, but not centrally, active. The anti-tussive mechanism of action of E121 seems to be K(ATP) channel dependent, whereas its bronchodilatory effects appear to be mediated via activation of both K(ATP) channels and β(2) receptors. Therefore, E121 may potentially represent a novel therapy for cough, particularly cough associated with airway obstruction.
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Affiliation(s)
- Ahmed Z El-Hashim
- Department of Applied Therapeutics, Faculty of Pharmacy, Kuwait University, Kuwait.
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Chikhalikar S, Bhawe V, Ghotekar B, Jachak M, Ghagare M. Synthesis of pyridin-2(1H)-one derivatives via enamine cyclization. J Org Chem 2011; 76:3829-36. [PMID: 21480675 DOI: 10.1021/jo200197g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nucleophilic vinylic substitution reaction of the aliphatic enaminone 3-dimethylamino-2-formyl acrylonitrile 1 with the nucleophiles malononitrile and ethyl cyanoacetate produced the two unusual reaction adducts 3a and 3b in good to moderate yield under milder reaction conditions. Upon reaction with aromatic amines, these adducts yielded enamines 4 and 5, which eventually cyclized in the presence of base to produce the novel pyridin-2(1H)-one derivatives 8 and 9.
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Affiliation(s)
- Sandip Chikhalikar
- Department of Chemistry, Bharatiya Vidya Bhavan's N.M. Institute of Science, Bhavan's College, Munshi Nagar, Andheri (W), Mumbai 400058, MS India
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Wang ZJ, Sun L, Jackson PL, Scott KR, Heinbockel T. A substituted anilino enaminone acts as a novel positive allosteric modulator of GABA(A) receptors in the mouse brain. J Pharmacol Exp Ther 2010; 336:916-24. [PMID: 21163867 DOI: 10.1124/jpet.110.173740] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A small library of anilino enaminones was analyzed for potential anticonvulsant agents. We examined the effects of three anilino enaminones on neuronal activity of output neurons, mitral cells (MC), in an olfactory bulb brain slice preparation using whole-cell patch-clamp recording. These compounds are known to be effective in attenuating pentylenetetrazol-induced convulsions. Among the three compounds tested, 5-methyl-3-(4-trifluoromethoxy-phenylamino)-cyclohex-2-enone (KRS-5Me-4-OCF₃) showed potent inhibition of MC activity with an EC₅₀ of 24.5 μM. It hyperpolarized the membrane potential of MCs accompanied by suppression of spontaneous firing. Neither ionotropic glutamate receptor blockers nor a GABA(B) receptor blocker prevented the KRS-5Me-4-OCF(3)-evoked inhibitory effects. In the presence of GABA(A) receptor antagonists, KRS-5Me-4-OCF(3) completely failed to evoke inhibition of MC spiking activity, suggesting that KRS-5Me-4-OCF₃-induced inhibition may be mediated by direct action on GABA(A) receptors or indirect action through the elevation of tissue GABA levels. Neither vigabatrin (a selective GABA-T inhibitor) nor 1,2,5,6-tetrahydro-1-[2-[[(diphenylmethylene)amino]oxy]ethyl]-3-pyridinecarboxylic acid hydrochloride (NNC-711) (a selective inhibitor of GABA uptake by GABA transporter 1) eliminated the effect of KRS-5ME-4-OCF₃ on neuronal excitability, indicating that the inhibitory effect of the enaminone resulted from direct activation of GABA(A) receptors. The concentration-response curves for GABA are left-shifted by KRS-5Me-4-OCF₃, demonstrating that KRS-5Me-4-OCF₃ enhanced GABA affinity and acted as a positive allosteric modulator of GABA(A) receptors. The effect of KRS-5Me-4-OCF₃ was blocked by applying a benzodiazepine site antagonist, suggesting that KRS-5Me-4-OCF₃ binds at the classic benzodiazepine site to exert its pharmacological action. The results suggest clinical use of enaminones as anticonvulsants in seizures and as a potential anxiolytic in mental disorders.
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Affiliation(s)
- Ze-Jun Wang
- Department of Anatomy, Howard University College of Medicine, Washington, DC 20059, USA
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El-Hashim A, Yousefi S, Edafiogho I, Raghupathy R, Yousif M, Simon HU. Anti-inflammatory and immunosuppressive effects of the enaminone E121. Eur J Pharmacol 2009; 632:73-8. [PMID: 20006602 DOI: 10.1016/j.ejphar.2009.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 11/19/2009] [Accepted: 12/07/2009] [Indexed: 10/20/2022]
Abstract
Asthma is a chronic inflammatory disease of the airways. The treatment of asthma is far from optimal and hence the need for novel therapeutic agents exists. The purpose of this study was to assess the anti-asthma effects of an enaminone, E121, and also its effects on human peripheral blood mononuclear cell proliferation and cytokine release. The effects of E121 were assessed in an ovalbumin-induced model of airway inflammation and airway hyperresponsiveness. In addition, the effects of E121 on phytohemagglutinin (PHA), anti-CD3 monoclonal antibody and lipopolysaccharide (LPS)-induced human peripheral blood mononuclear cell proliferation and cytokine release, respectively, were assessed. Treatment of mice with E121 significantly decreased the ovalbumin-induced increase in airway total cell influx and eosinophil infiltration and this was associated with an inhibition of ovalbumin-induced airway hyperresponsiveness. Moreover, E121 reduced PHA and anti-CD3-induced human peripheral blood mononuclear cell proliferation in vitro. E121 also inhibited PHA, anti-CD3 monoclonal antibody and LPS-induced cytokine release from human peripheral blood mononuclear cell cultures. These findings indicate that E121 exhibits anti-inflammatory and immunosuppressive activities.
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Affiliation(s)
- Ahmed El-Hashim
- Department of Applied Therapeutics, Kuwait University, Kuwait.
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Chemo-, regio- and stereospecific addition of amino acids to acylacetylenes: a facile synthesis of new N-acylvinyl derivatives of amino acids. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.09.069] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Synthesis and structure–activity relationship studies of theophylline analogs on population responses in the rat hippocampus in vitro. Bioorg Med Chem 2008; 16:8142-50. [DOI: 10.1016/j.bmc.2008.07.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2008] [Revised: 07/15/2008] [Accepted: 07/17/2008] [Indexed: 11/21/2022]
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