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1.
Neurochem Res ; 44(10): 2435-2447, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31535355

RESUMO

Vinpocetine is considered as neuroprotectant drug and used for treatment of brain ischemia and cognitive deficiencies for decades. A number of enzymes, channels and receptors can bind vinpocetine, however the mechanisms of many effects' are still not clear. The present study investigated the effects of vinpocetine from the mitochondrial bioenergetic aspects. In primary brain capillary endothelial cells the purinergic receptor-stimulated mitochondrial Ca2+ uptake and efflux were studied. Vinpocetine exerted a partial inhibition on the mitochondrial calcium efflux. In rodent brain synaptosomes vinpocetine (30 µM) inhibited respiration in uncoupler stimulated synaptosomes and decreased H2O2 release from the nerve terminals in resting and in complex I inhibited conditions, respectively. In isolated rat brain mitochondria using either complex I or complex II substrates leak respiration was stimulated, but ADP-induced respiration was inhibited by vinpocetine. The stimulation of oxidation was associated with a small extent of membrane depolarization. Mitochondrial H2O2 production was inhibited by vinpocetine under all conditions investigated. The most pronounced effects were detected with the complex II substrate succinate. Vinpocetine also mitigated both Ca2+-induced mitochondrial Ca2+-release and Ca2+-induced mitochondrial swelling. It lowered the rate of mitochondrial ATP synthesis, while increasing ATPase activity. These results indicate more than a single mitochondrial target of this vinca alkaloid. The relevance of the affected mitochondrial mechanisms in the anti ischemic effect of vinpocetine is discussed.


Assuntos
Encéfalo/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos , Alcaloides de Vinca/farmacologia , Animais , Encéfalo/metabolismo , Cálcio/metabolismo , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos Wistar , Sinaptossomos/metabolismo
2.
Neurochem Res ; 44(8): 2020-2029, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31264110

RESUMO

The neurotoxic effects of aluminum are generally associated with reduced antioxidant capacity, increased oxidative stress and apoptosis, which lead to the induction of neurodegenerative processes. Curcumin has a lipophilic polyphenol character and effects of antioxidant and anti-apoptotic. The present study was undertaken to examine possible aluminum exposure in rats brain synaptosomes and to investigate whether protective and therapeutic effects of curcumin on biochemical and morphological changes in both pre- and post-treated groups. Aluminum chloride (AlCl3) at 50 µM concentration and curcumin at 5 and 10 µg/mL doses were applied to hippocampal synaptosomes of rats according to experimental design. Biochemical effects were evaluated by MTT cytotoxicity, malondialdehyde (MDA) levels, nitric oxide (NO) levels, glutathione (GSH) levels, caspase 3 activities, cytochrome c levels, DNA fragmentation values and protein levels. Morphological examinations were done by TEM analysis. AlCI3 exposure in the synaptosomes enhanced oxidative stress, triggered apoptosis and caused ultrastructural alterations which were well reflected in the TEM images. Curcumin pre-treatment slightly ameliorated the MDA levels, NO levels, cytochrome c levels and caspase 3 activities in AlCI3-exposed synaptosomes, but these results were not statistically significant. Furthermore, curcumin post-treatment significantly improved oxidative damage and morphological alterations, and suppressed cytochrome c and caspase 3 activities. Taken together, our data showed that curcumin had more therapeutic effects than protective effects in AlCI3-induced neurotoxicity. Nevertheless, the therapeutic (post-protective) effects of curcumin should be further investigated in in vivo neurodegenerative models involving behavioral tests.


Assuntos
Alumínio/efeitos adversos , Curcumina/uso terapêutico , Hipocampo/efeitos dos fármacos , Síndromes Neurotóxicas/tratamento farmacológico , Sinaptossomos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/prevenção & controle , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
3.
Pharmacol Res Perspect ; 7(3): e00484, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31149340

RESUMO

Mutations in leucine-rich repeat kinase 2 (LRRK2) gene have been pathogenically linked to Parkinson's disease, and pharmacological inhibition of LRRK2 is being pursued to tackle nigro-striatal dopaminergic neurodegeneration. However, LRRK2 kinase inhibitors may have manifold actions, affecting not only pathological mechanisms in dopaminergic neurons but also physiological functions in nondopaminergic neurons. Therefore, we investigated whether LRRK2 kinase inhibitors differentially modulate dopamine and glutamate release from the mouse striatum and cerebral cortex. Spontaneous and KCl-evoked [3H]-dopamine and glutamate release from superfused synaptosomes obtained from wild-type and LRRK2 knock-out, kinase-dead or G2019S knock-in mice was measured. Two structurally unrelated inhibitors, LRRK2-IN-1 and GSK2578215A, were tested. LRRK2, phosphoSerine1292 and phosphoSerine935 LRRK2 levels were measured in all genotypes, and target engagement was evaluated by monitoring phosphoSerine935 LRRK2. LRRK2-IN-1 inhibited striatal glutamate but not dopamine release; GSK2578215A inhibited striatal dopamine and cortical glutamate but enhanced striatal glutamate release. LRRK2-IN-1 reduced striatal and cortical phosphoSerine935 levels whereas GSK2578215A inhibited only the former. Neither LRRK2 inhibitor affected neurotransmitter release in LRRK2 knock-out and kinase-dead mice; however, they facilitated dopamine without affecting striatal glutamate in G2019S knock-in mice. GSK2578215A inhibited cortical glutamate release in G2019S knock-in mice. We conclude that LRRK2-IN-1 and GSK2578215A modulate exocytosis by blocking LRRK2 kinase activity, although their effects vary depending on the nerve terminal examined. The G2019S mutation unravels a dopamine-promoting action of LRRK2 inhibitors while blunting their effects on glutamate release, which highlights their positive potential for the treatment of PD, especially of LRRK2 mutation carriers.


Assuntos
Aminopiridinas/farmacologia , Benzamidas/farmacologia , Benzodiazepinonas/farmacologia , Corpo Estriado/citologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Pirimidinas/farmacologia , Córtex Visual/citologia , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Exocitose , Técnicas de Introdução de Genes , Ácido Glutâmico/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Masculino , Camundongos , Fosforilação , Serina/metabolismo , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Córtex Visual/efeitos dos fármacos , Córtex Visual/metabolismo
4.
Toxicol In Vitro ; 60: 389-399, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31195087

RESUMO

A well-known cationic biocide of guanidine polymer family, polyhexamethylene guanidine hydrochloride (PHMG) has been tested against smooth muscle cells isolated from swine myometrium, synaptosomes of rat brain nerve terminals and rat blood platelets for the membrane action. It was established that PHMG blocked the activity of Na+,K+-ATPase of smooth muscle cells plasma membrane by 82.2 ±â€¯0.9% at a concentration of 7 ppm, whilst a dose-dependent depolarization of synaptosomes and platelets became appreciable at 100-500 ppm. Comparative studies by the methods of mass spectrometry (MALDI-TOF and PDMS-TOF), viscosimetry, dynamic light scattering and model phospholipid membranes revealed PHMG oligomers with various number of repeat units (8-16) that formed K+-selective potential-dependent pores in sterol-free phosphatidylethanolamine-containing phospholipid bilayers at a concentration of 1 ppm. Obtained results suggest that besides acidic lipids and membrane proteins phosphatidylethanolamine and cholesterol are the other major factors responsible for the differences between PHMG-induced plasma membrane depolarization of microbial and eukaryotic cells and thus, diverse modes of PHMG membrane action.


Assuntos
Plaquetas/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Desinfetantes/toxicidade , Guanidinas/toxicidade , Miócitos de Músculo Liso/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos , Animais , Bicamadas Lipídicas/metabolismo , Masculino , Fosfolipídeos/metabolismo , Porosidade , Ratos Wistar
5.
Eur J Pharmacol ; 855: 65-74, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059709

RESUMO

Neuropathic pain is a common type of chronic pain caused by trauma or chemotherapy. However, this type of pain is undertreated. TsNTxP is a non-toxic protein isolated from the venom of the scorpion Tityus serrulatus, and it is structurally similar to neurotoxins that interact with voltage-gated sodium channels. However, the antinociceptive properties of this protein have not been characterized. The purpose of this study was to investigate the antinociceptive effects of TsNTxP in acute and neuropathic pain models. Male and female Swiss mice (25-30 g) were exposed to different models of acute pain (tail-flick test and nociception caused by capsaicin intraplantar injection) or neuropathic pain (chronic pain syndrome induced by paclitaxel or chronic constriction injury of the sciatic nerve). Hypersensitivity to mechanical or cold stimuli were evaluated in the models of neuropathic pain. The ability of TsNTxP to alter the release of glutamate in mouse spinal cord synaptosomes was also evaluated. The results showed that TsNTxP exerted antinociceptive effects in the tail-flick test to a thermal stimulus and in the intraplantar capsaicin administration model. Furthermore, TsNTxP was non-toxic and exerted antiallodynic effects in neuropathic pain models induced by chronic constriction injury of the sciatic nerve and administration of paclitaxel. TsNTxP reduced glutamate release from mouse spinal cord synaptosomes following stimulation with potassium chloride (KCl) or capsaicin. Thus, this T. serrulatus protein may be a promising non-toxic drug for the treatment of neuropathic pain.


Assuntos
Analgésicos/farmacologia , Proteínas de Artrópodes/farmacologia , Ácido Glutâmico/metabolismo , Venenos de Escorpião/química , Escorpiões , Analgésicos/uso terapêutico , Animais , Proteínas de Artrópodes/uso terapêutico , Feminino , Masculino , Camundongos , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Medula Espinal/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
6.
Food Funct ; 10(5): 2720-2728, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31033966

RESUMO

Piperine is the crucial alkaloid component of black pepper (Piper nigrum Linn.) and has neuroprotective effects. Because inhibition of glutamatergic excitatory neurotransmission is a possible mechanism involved in neuroprotection, we investigated the effect of piperine on the 4-aminopyridine (4-AP)-evoked release of glutamate from rat hippocampal synaptosomes. Piperine inhibited 4-AP-evoked glutamate release, and the inhibition was prevented by the chelation of extracellular Ca2+ ions and a vesicular transporter inhibitor. Piperine reduced the 4-AP-evoked elevation of intrasynaptosomal Ca2+ levels but did not affect the synaptosomal membrane potential. In the presence of ω-conotoxin MVIIC, an N- and P/Q-type channel blocker, the piperine-mediated inhibition of 4-AP-evoked glutamate release was markedly reduced; however, dantrolene and CGP37157, which are intracellular Ca2+-release inhibitors, did not alter the piperine effect. In addition, immunocytochemical analysis confirmed the presence of presynaptic 5-hydroxytryptamine 1A (5-HT1A) receptor proteins. The glutamate release-inhibiting effect of piperine was discovered to be prevented by the 5-HT1A receptor antagonist WAY100635 and the G protein ßγ subunit inhibitor gallein; however, it was unaffected by the adenylate cyclase inhibitor SQ22536 or the protein kinase A inhibitor PKI622. These results suggest that piperine inhibits glutamate release from rat hippocampal nerve terminals by reducing Ca2+ influx through N- and P/Q-type Ca2+ channels and that the activation of presynaptic 5-HT1A receptors and the G protein ßγ subunit is involved in this effect.


Assuntos
Alcaloides/farmacologia , Benzodioxóis/farmacologia , Cálcio/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Receptor 5-HT1A de Serotonina/metabolismo , 4-Aminopiridina/metabolismo , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/genética , Subunidades gama da Proteína de Ligação ao GTP/genética , Hipocampo/efeitos dos fármacos , Masculino , Piper nigrum/química , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor 5-HT1A de Serotonina/genética , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
7.
J Med Food ; 22(7): 696-702, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30985232

RESUMO

Evidence indicates that indirect inhibitory regulation of glutamatergic transmission, via reducing glutamate release, may induce neuroprotection. The present work was designed to examine whether allicin, a major component of garlic with neuroprotective effects, affected the release of glutamate evoked by 4-aminopyridine in rat cerebrocortical nerve terminals (synaptosomes). Allicin caused a potent inhibition on the release of glutamate evoked by 4-aminopyridine, and this inhibitory effect was abolished in the presence of Ca2+-free medium and vesicular transporter inhibitor. Allicin decreased the 4-aminopyridine-evoked elevation of intrasynaptosomal Ca2+ levels, but had no effect on the synaptosomal plasma membrane potential. The allicin-mediated inhibition of glutamate release was prevented by the N- and P/Q-type channel blocker and the protein kinase C (PKC) inhibitor, but was not affected by the intracellular Ca2+-release inhibitors, mitogen-activated protein kinase inhibitor, and protein kinase A inhibitor. Western blotting data also showed that allicin significantly reduced the phosphorylation of PKC. Together, these data indicate that in rat cerebrocortical nerve terminals, allicin depresses glutamate release and appears to decrease N- and P/Q-type Ca2+ channel and PKC activity.


Assuntos
Cálcio/metabolismo , Córtex Cerebral/metabolismo , Ácido Glutâmico/metabolismo , Terminações Nervosas/metabolismo , Proteína Quinase C/metabolismo , Ácidos Sulfínicos/farmacologia , Animais , Córtex Cerebral/efeitos dos fármacos , Masculino , Terminações Nervosas/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteína Quinase C/genética , Ratos , Ratos Sprague-Dawley , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
8.
J Pharmacol Exp Ther ; 369(3): 328-336, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30898867

RESUMO

ß-Methylphenethylamine [(BMPEA), 2-phenylpropan-1-amine] is a structural isomer of amphetamine (1-phenylpropan-2-amine) that has been identified in preworkout and weight loss supplements, yet little information is available about its pharmacology. Here, the neurochemical and cardiovascular effects of BMPEA and its analogs, N-methyl-2-phenylpropan-1-amine (MPPA) and N,N-dimethyl-2-phenylpropan-1-amine (DMPPA), were compared with structurally related amphetamines. As expected, amphetamine and methamphetamine were potent substrate-type releasing agents at dopamine transporters (DATs) and norepinephrine transporters (NETs) in rat brain synaptosomes. BMPEA and MPPA were also substrates at DATs and NETs, but they were at least 10-fold less potent than amphetamine. DMPPA was a weak substrate only at NETs. Importantly, the releasing actions of BMPEA and MPPA were more potent at NETs than DATs. Amphetamine produced significant dose-related increases in blood pressure (BP), heart rate (HR), and locomotor activity in conscious rats fitted with surgically implanted biotelemetry transmitters. BMPEA, MPPA, and DMPPA produced increases in BP that were similar to the effects of amphetamine, but the compounds failed to substantially affect HR or activity. The hypertensive effect of BMPEA was reversed by the α-adrenergic antagonist prazosin but not the ganglionic blocker chlorisondamine. Radioligand binding at various G protein-coupled receptors did not identify nontransporter sites of action that could account for cardiovascular effects of BMPEA or its analogs. Our results show that BMPEA, MPPA, and DMPPA are biologically active. The compounds are unlikely to be abused due to weak effects at DATs, but they could produce adverse cardiovascular effects via substrate activity at peripheral NET sites.


Assuntos
Anfetaminas/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais/efeitos adversos , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Animais , Frequência Cardíaca/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Temperatura Ambiente
9.
Neurochem Int ; 126: 59-63, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30858017

RESUMO

We investigated the impact of the prolonged exposure of rat hippocampal synaptosomes to CXCL12 (3 nM) on the NMDA-mediated release of [3H]D-aspartate ([3H]D-Asp) or [3H]noradrenaline ([3H]NA). Synaptosomes were stimulated twice with NMDA/CXCL12 and the amount of the NMDA-evoked tritium release (S1 and S2) quantified to calculate the S2/S1 ratio. The S2/S1 ratio for both transmitters was drastically decreased by 3 nM CXCL12 between the two stimuli (CXCL12-treated synaptosomes) in a AMD3100-sensitive manner. The phosphorylation of the GluN1 subunit in Ser 896 was reduced in CXCL12-treated synaptosomes, while the overall amount of GluN1 and GluN2B proteins as well as the GluN2B insertion in synaptosomal plasmamembranes were unchanged. We conclude that the CXCR4/NMDA cross-talk is dynamically regulated by the time of activation of the CXCR4s. Our results unveil a functional cross-talk that might account for the severe impairments of central transmission that develop in pathological conditions characterized by CXCL12 overproduction.


Assuntos
Hipocampo/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptores CXCR4/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptossomos/metabolismo , Animais , Quimiocina CXCL12/farmacologia , Hipocampo/efeitos dos fármacos , N-Metilaspartato/farmacologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores CXCR4/agonistas , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sinaptossomos/efeitos dos fármacos
10.
Toxicol Lett ; 307: 72-80, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30858090

RESUMO

We hypothesized that supraphysiological administration of the anabolic-androgenic steroids (AAS) like testosterone (TEST) and nandrolone decanoate (NAND) might differentially affect synaptic and extrasynaptic components of mitochondrial bioenergetics, thereby resulting in memory impairment. Oil (VEH), NAND or TEST (15 mg/Kg) were daily administered to male CF-1 albino mice for 19-days. We evaluated in the synaptosomes and extrasynaptic mitochondria, Ca2+ influx/efflux, membrane potential ΔÑ°m, oxidative respiratory states, dehydrogenases activity, H2O2 production, Tau phosphorylation, and spatial memory in the Morris water maze (MWM). In synaptosomes, both AAS increased Ca2+ influx and Na+ dependent efflux. In extrasynaptic mitochondria, NAND increased the Ca2+ influx. NAND prominently impaired ΔÑ°m formation and dissipation in synaptosomal and extrasynaptic mitochondria, while the effect of TEST was less pronounced. TEST increased the Reserve Respiratory Capacity in synaptosomes, and NAND decreased dehydrogenases activity in synaptic and extrasynaptic mitochondria. Also, NAND increased H2O2 production by synaptosomes and extrasynaptic mitochondria. NAND increased pTauSer396 in synaptosomes. Both AAS did not impair memory performance on MWM. We highlight that high doses of NAND cause neurotoxic effects to components of synaptic and extrasynaptic mitochondrial bioenergetics, like calcium influx, membrane potential and H2O2 production. TEST was less neurotoxic to synaptic and extrasynaptic mitochondrial bioenergetics responses.


Assuntos
Mitocôndrias/efeitos dos fármacos , Nandrolona/farmacologia , Sinapses/efeitos dos fármacos , Congêneres da Testosterona/farmacologia , Testosterona/farmacologia , Animais , Western Blotting , Cálcio/metabolismo , Metabolismo Energético/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Nandrolona/efeitos adversos , Consumo de Oxigênio/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Sinapses/metabolismo , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Testosterona/efeitos adversos , Congêneres da Testosterona/efeitos adversos , Proteínas tau/metabolismo
11.
Mol Brain ; 12(1): 11, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736828

RESUMO

We aimed to test the therapeutic effects of baicalin on attention deficit hyperactivity disorder (ADHD) in an animal model and to explain the potential mechanism. We investigated the therapeutic effects and mechanisms of baicalin in a spontaneously hypertensive rat (SHR) model of ADHD depending on the dopamine (DA) deficit theory. In this study, fifty SHRs were randomly divided into five groups: methylphenidate (MPH), baicalin (50 mg/kg, 100 mg/kg, or 150 mg/kg), and saline-treated. Ten Wistar Kyoto (WKY) rats were used as controls. All rats were orally administered the treatment for four weeks. Motor activity, spatial learning and memory ability were assessed with the open-field and Morris water-maze tests. The mRNA and protein levels of tyrosine hydroxylase (TH), vesicular monoamine transporter 2 (VMAT2), synaptosomal-associated protein of molecular mass 25kD (SNAP25) and synataxin 1a in synaptosomes were detected with real-time polymerase chain reaction (PCR) and Western blot. In addition, DA levels were measured in the prefrontal cortex and striatum. The results indicated that both MPH and baicalin at doses of 150 mg/kg and 100 mg/kg significantly decreased the hyperactivity and improved the spatial learning memory deficit in the SHRs and increased the synaptosomal mRNA and protein levels of TH, SNAP25, VMAT2 and synataxin 1a compared with saline treatment. MPH significantly increased DA levels in both the prefrontal cortex (PFC) and striatum, while baicalin significantly increased DA levels only in the striatum. The results of the present study showed that baicalin treatment was effective for controlling the core symptoms of ADHD. Baicalin increased DA levels only in the striatum, which suggested that baicalin may target the striatum. The increased DA levels may partially be attributed to the increased mRNA and protein expression of TH, SNAP25, VMAT2, and syntaxin 1a. Therefore, these results suggested that the pharmacological effects of baicalin were associated with the synthesis, vesicular localization, and release of DA and might be effective in treating ADHD. However, further studies are required to better understand the molecular mechanisms underlying these findings.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Dopamina/metabolismo , Flavonoides/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos , Flavonoides/farmacologia , Crescimento e Desenvolvimento/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Movimento , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Endogâmicos SHR , Tempo de Reação/efeitos dos fármacos , Aprendizagem Espacial/efeitos dos fármacos , Natação , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Sinaptossomos/ultraestrutura
12.
Fitoterapia ; 133: 180-185, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659875

RESUMO

Aquilariaenes A-H (1-8), eight new diterpenoids and nor-diterpenoids (1-8) belonging to abietane or pimarane, were isolated from the petroleum ether extract of Chinese eaglewood. Their structures were elucidated on the basis of extensive spectroscopic methods including HRESIMS, IR, 1D and 2D NMR spectroscopic data analyses. Antidepressant activities of isolates for in vitro inhibition of serotonin and norepinephrine reuptake in rat brain synaptosomes were evaluated.


Assuntos
Antidepressivos/farmacologia , Diterpenos/farmacologia , Sinaptossomos/efeitos dos fármacos , Thymelaeaceae/química , Animais , Antidepressivos/isolamento & purificação , Diterpenos/isolamento & purificação , Estrutura Molecular , Norepinefrina/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Ratos , Serotonina/metabolismo
13.
J Enzyme Inhib Med Chem ; 34(1): 500-509, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30696301

RESUMO

Several ellagitannins inhibited the activity of protein phosphatase-1 (PP1) and -2 A (PP2A) catalytic subunits (PP1c and PP2Ac) with preferential suppression of PP1c over PP2Ac. The inhibitory potency for PP1c followed the order of tellimagrandin I > mahtabin A > praecoxin B > 1.2-Di-O-galloyl-4.6-(S)-HHDP-ß-D-glucopyranose > pedunculagin with IC50 values ranging from 0.20 µM to 2.47 µM. The interaction of PP1c and tellimagrandin I was assessed by NMR saturation transfer difference, surface plasmon resonance, isothermal titration calorimetry, and microscale thermophoresis based binding techniques. Tellimagrandin I suppressed viability and phosphatase activity of HeLa cells, while mahtabin A was without effect. Conversely, mahtabin A increased the phosphorylation level of SNAP-25Thr138 and suppressed exocytosis of cortical synaptosomes, whereas tellimagrandin I was without influence. Our results establish ellagitannins as partially selective inhibitors of PP1 and indicate that these polyphenols may act distinctly in cellular systems depending on their membrane permeability and/or their actions on cell membranes.


Assuntos
Calorimetria/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/farmacologia , Proteína Fosfatase 1/antagonistas & inibidores , Proteína Fosfatase 2/antagonistas & inibidores , Animais , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Exocitose/efeitos dos fármacos , Células HeLa , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Camundongos , Músculo Esquelético/enzimologia , Fosforilação , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície , Proteína 25 Associada a Sinaptossoma/metabolismo , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
14.
Mol Neurobiol ; 56(1): 56-60, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29675577

RESUMO

The synthesis of brain metabolic DNA (BMD) is modulated by learning and circadian oscillations and is not involved in cell division or DNA repair. Data from rats have highlighted its prevalent association with the mitochondrial fraction and its lack of identity with mtDNA. These features suggested that BMD could be localized in synaptosomes that are the major contaminants of brain mitochondrial fractions. The hypothesis has been examined by immunochemical analyses of the large synaptosomes of squid optic lobes that are readily prepared and identified. Optic lobe slices were incubated with 5-bromo-2-deoxyuridine (BrdU) and the isolated synaptosomal fraction was exposed to the green fluorescent anti-BrdU antibody. This procedure revealed that newly synthesized BrdU-labeled BMD is present in a significant percent of the large synaptosomes derived from the nerve terminals of retinal photoreceptor neurons and in synaptosomal bodies of smaller size. Synaptosomal BMD synthesis was strongly inhibited by actinomycin D. In addition, treatment of the synaptosomal fraction with Hoechst 33258, a blue fluorescent dye specific for dsDNA, indicated that native DNA was present in all synaptosomes. The possible role of synaptic BMD is briefly discussed.


Assuntos
DNA/metabolismo , Decapodiformes/metabolismo , Sinaptossomos/metabolismo , Animais , DNA/biossíntese , Dactinomicina/farmacologia , Sinaptossomos/efeitos dos fármacos
15.
Psychopharmacology (Berl) ; 236(3): 953-962, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30345459

RESUMO

RATIONALE: Synthetic cathinones continue to emerge in recreational drug markets worldwide. 1-(1,3-Benzodioxol-5-yl)-2-(methylamino)butan-1-one (butylone) and 1-(1,3-benzodioxol-5-yl)-2-(methylamino)pentan-1-one (pentylone) are derivatives of the cathinone compound, 1-(1,3-benzodioxol-5-yl)-2-(methylamino)propan-1-one (methylone), that are being detected in drug products and human casework. OBJECTIVES: The purpose of the present study was to examine the neuropharmacology of butylone and pentylone using in vitro and in vivo methods. METHODS: In vitro uptake and release assays were carried out in rat brain synaptosomes and in cells expressing human dopamine transporters (DAT) and 5-HT transporters (SERT). In vivo microdialysis was performed in the nucleus accumbens of conscious rats to assess drug-induced changes in neurochemistry. RESULTS: Butylone and pentylone were efficacious uptake blockers at DAT and SERT, though pentylone was more DAT-selective. Both drugs acted as transporter substrates that evoked release of [3H]5-HT at SERT, while neither evoked release at DAT. Consistent with the release data, butylone and pentylone induced substrate-associated inward currents at SERT but not DAT. Administration of butylone or pentylone to rats (1 and 3 mg/kg, i.v.) increased extracellular monoamines and motor activity, but pentylone had weaker effects on 5-HT and stronger effects on motor stimulation. CONCLUSIONS: Our data demonstrate that increasing the α-carbon chain length of methylone creates "hybrid" transporter compounds which act as DAT blockers but SERT substrates. Nevertheless, butylone and pentylone elevate extracellular dopamine and stimulate motor activity, suggesting both drugs possess significant risk for abuse.


Assuntos
Alcaloides/farmacologia , Anfetaminas/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Antagonistas de Dopamina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/antagonistas & inibidores , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Medicamentos Sintéticos/farmacologia , 3,4-Metilenodioxianfetamina/análogos & derivados , 3,4-Metilenodioxianfetamina/química , 3,4-Metilenodioxianfetamina/farmacologia , Alcaloides/química , Anfetaminas/química , Animais , Estimulantes do Sistema Nervoso Central/química , Antagonistas de Dopamina/química , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Masculino , Metanfetamina/análogos & derivados , Metanfetamina/química , Metanfetamina/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Medicamentos Sintéticos/química
16.
Psychopharmacology (Berl) ; 236(3): 915-924, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30341459

RESUMO

RATIONALE: Novel synthetic "bath salt" cathinones continue to appear on the street as abused and addictive drugs. The range of subjective experiences produced by different cathinones suggests that some compounds have primarily dopaminergic activity (possible stimulants) while others have primarily serotonergic activity (possible empathogenics). An understanding of the structure activity relationships (SARs) of these compounds will help in assessing the likely behavioral effects of future novel structures, and to define potential therapeutic strategies to reverse any reinforcing effects. OBJECTIVES: A series of methcathinone analogs was systematically studied for their activity at the dopamine and serotonin transporters. Compound structures varied at the aromatic group, either by substituent or by replacement of the phenyl ring with a naphthalene or indole ring. METHODS: A novel, high-yielding synthesis of methcathinone hydrochlorides was developed which avoids isolation of the unstable free bases. Neurotransmitter transporter release activity was determined in rat brain synaptosomes as previously reported. Compounds were also screened for activity at the norepinephrine transporter. RESULTS: Twenty-eight methcathinone analogs were analyzed and fully characterized in dopamine and serotonin transporter release assays. Compounds substituted at the 2-position (ortho) were primarily dopaminergic. Compounds substituted at the 3-position (meta) were found to be much less dopaminergic, with some substituents favoring serotonergic activity. Compounds substituted at the 4-position (para) were found to be far more serotonergic, as were disubstituted compounds and other large aromatic groups. One exception was the fluoro-substituted analogs which seem to favor the dopamine transporter. CONCLUSIONS: The dopaminergic to serotonergic ratio can be manipulated by choice of substituent and location on the aromatic ring. It is therefore likely possible to tweak the subjective and reinforcing effects of these compounds by adjusting their structure. Certain substituents like a fluoro group tend to favor the dopamine transporter, while others like a trifluoromethyl group favor the serotonin transporter.


Assuntos
Encéfalo/metabolismo , Dopamina/metabolismo , Norepinefrina/metabolismo , Propiofenonas/farmacologia , Serotonina/metabolismo , Sinaptossomos/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/farmacologia , Masculino , Propiofenonas/química , Ratos , Inibidores de Captação de Serotonina/química , Inibidores de Captação de Serotonina/farmacologia , Relação Estrutura-Atividade , Sinaptossomos/efeitos dos fármacos
17.
Psychopharmacology (Berl) ; 236(3): 925-938, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30284596

RESUMO

RATIONALE: MDPV (3,4-methylenedioxypyrovalerone) is a synthetic cathinone present in bath salts. It is a powerful psychostimulant and blocker of the dopamine transporter (DAT), like cocaine. It is known that acute exposure to psychostimulants induces rapid changes in DAT function. OBJECTIVES: To investigate the effects of MDPV on DAT function comparing with cocaine. METHODS: Binding of [3H]WIN 35428 was performed on PC 12 cells treated with MDPV and washed. Rat striatal synaptosomes were incubated with MDPV or cocaine (1 µM) for 1 h and [3H]dopamine (DA) uptake was performed. Also, different treatments with MDPV or cocaine were performed in Sprague-Dawley rats to assess locomotor activity and ex vivo [3H]DA uptake. RESULTS: MDPV increased surface [3H]WIN 35428 binding on PC 12 cells. In vitro incubation of synaptosomes with MDPV produced significant increases in Vmax and KM for [3H]DA uptake. In synaptosomes from MDPV- (1.5 mg/kg, s.c.) and cocaine- (30 mg/kg, i.p.) treated rats, there was a significantly higher and more persistent increase in [3H]DA uptake in the case of MDPV than cocaine. Repeated doses of MDPV developed tolerance to this DAT upregulation and 24 h after the 5-day treatment with MDPV, [3H]DA uptake was reduced. However, a challenge with the same drugs after withdrawal recovered the DAT upregulation by both drugs and showed an increased response to MDPV vs the first dose. At the same time, animals were sensitized to the stereotypies induced by both psychostimulants. CONCLUSIONS: MDPV induces a rapid and reversible functional upregulation of DAT more powerfully and lasting than cocaine.


Assuntos
Benzodioxóis/farmacologia , Cocaína/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/agonistas , Proteínas da Membrana Plasmática de Transporte de Dopamina/biossíntese , Inibidores da Captação de Dopamina/farmacologia , Pirrolidinas/farmacologia , Animais , Benzodioxóis/metabolismo , Estimulantes do Sistema Nervoso Central/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Cocaína/análogos & derivados , Cocaína/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Inibidores da Captação de Dopamina/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Células PC12 , Ligação Proteica/fisiologia , Pirrolidinas/metabolismo , Ratos , Ratos Sprague-Dawley , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
18.
Psychopharmacology (Berl) ; 236(2): 641-655, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30377748

RESUMO

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease. The present study investigated the effects of 50 and 100 mg/kg berberine (BRB) on recognition memory, oxidative stress, and purinergic neurotransmission, in a model of sporadic dementia of the Alzheimer's type induced by intracerebroventricular (ICV) injection of streptozotocin (STZ) in rats. Rats were submitted to ICV-STZ 3 mg/kg or saline, and 3 days later, were started on a treatment of BRB or saline for 21 days. The results demonstrated that BRB was effective in protecting against memory impairment, increased reactive oxygen species, and the subsequent increase in protein and lipid oxidation in the cerebral cortex and hippocampus, as well as δ-aminolevulinate dehydratase inhibition in the cerebral cortex. Moreover, the decrease in total thiols, and the reduced glutathione and glutathione S-transferase activity in the cerebral cortex and hippocampus of ICV-STZ rats, was prevented by BRB treatment. Besides an antioxidant effect, BRB treatment was capable of preventing decreases in ecto-nucleoside triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase (EC-5'-Nt), and adenosine deaminase (ADA) activities in synaptosomes of the cerebral cortex and hippocampus. Thus, our data suggest that BRB exerts a neuroprotective effect on recognition memory, as well as on oxidative stress and oxidative stress-related damage, such as dysfunction of the purinergic system. This suggests that BRB may act as a promising multipotent agent for the treatment of AD.


Assuntos
Berberina/farmacologia , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , /efeitos dos fármacos , 5'-Nucleotidase/efeitos dos fármacos , 5'-Nucleotidase/metabolismo , Adenosina Desaminase/efeitos dos fármacos , Adenosina Desaminase/metabolismo , Doença de Alzheimer/psicologia , Animais , Antibióticos Antineoplásicos/toxicidade , Antioxidantes , Encéfalo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Glutationa , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Injeções Intraventriculares , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Oxirredução/efeitos dos fármacos , Pirofosfatases/efeitos dos fármacos , Pirofosfatases/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Estreptozocina/toxicidade , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/enzimologia
19.
Life Sci ; 216: 215-226, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30447303

RESUMO

Diosmetin is an O­methylated flavone found naturally in citrus fruit, and it was identified in Amphilophium crucigerum (L.), a plant popularly used as an analgesic. This compound had different pharmacological effects and presented a chemical structure like the flavonoid eriodyctiol that exhibited antinociceptive effects by TRPV1 antagonism. However, the possible antinociceptive effect of this compound was not well documented. Thus, the goal of the present study was to evaluate the antinociceptive effect of diosmetin and its mechanism of action. The diosmetin effect on different pain models and its possible adverse effects were assessed on adult Swiss male mice (25-30 g). Mice spinal cord samples were used on calcium influx and binding assays using TRPV1 agonists. First, it was observed that the diosmetin reduced calcium influx mediated by capsaicin in synaptosomes and displace the specific binding to [3H]-resiniferatoxin in membrane fractions from the spinal cord of mice. Diosmetin (0.15 to 1.5 mg/kg, intragastric, i.g.) presented antinociceptive and antiedematogenic effect in the capsaicin intraplantar test and induced antinociception in a noxious heat test (48 °C). Also, treatment with diosmetin reduced mechanical and heat hypersensitivity observed in a model of inflammatory or neuropathic pain. Acute diosmetin administration in mice did not induce locomotor or body temperature changes, or cause liver enzyme abnormalities or alter renal function. Moreover, there were no observed changes in gastrointestinal transit or induction of ulcerogenic activity after diosmetin administration. In conclusion, our results support the antinociceptive properties of diosmetin which seems to occur via TRPV1 antagonist in mice.


Assuntos
Analgésicos/farmacologia , Flavonoides/farmacologia , Neuralgia/tratamento farmacológico , Dor/tratamento farmacológico , Canais de Cátion TRPV/antagonistas & inibidores , Analgésicos/administração & dosagem , Analgésicos/toxicidade , Animais , Cálcio/metabolismo , Capsaicina/farmacologia , Modelos Animais de Doenças , Diterpenos/metabolismo , Relação Dose-Resposta a Droga , Flavonoides/administração & dosagem , Flavonoides/toxicidade , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Camundongos , Neuralgia/fisiopatologia , Dor/fisiopatologia , Medição da Dor , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Testes de Toxicidade
20.
ACS Chem Neurosci ; 10(1): 740-745, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30354055

RESUMO

Methcathinone analogs are appearing on the clandestine market at a rate nearly out-pacing the ability of investigators to examine them on an individual basis. To formulate structure-activity relationship (SAR) generalities, we examined the releasing ability of several simple methcathinone analogs at the three monoamine transporters (i.e., the dopamine, norepinephrine, and serotonin transporters, DAT, NET, and SERT, respectively) using in vitro assay methods. The analogs included methcathinone and 14 other compounds monosubstituted at the 2-, 3-, or 4-position. In general, (a) the 2-substituted analogs were less potent than either the 3- or 4-substituted analogs, (b) the 3- and 4-substituted analogs were relatively similar in potency, (c) methcathinone was the most selective as a DAT-releasing agent, and (d) the 3- and 4-CF3 analogs were the least DAT-selective. For the 15 compounds, there was a significant correlation ( r > 0.9) between DAT and NET potency, suggesting relatively similar structure-activity relationships (at least for the compounds examined here). Several of the compounds have appeared on the clandestine market since our studies were initiated, and the present results provide new information on how they might act.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/efeitos dos fármacos , Propiofenonas/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/efeitos dos fármacos , Inibidores de Captação de Serotonina/farmacologia , Animais , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Masculino , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Propiofenonas/química , Ratos Sprague-Dawley , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Relação Estrutura-Atividade , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
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