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1.
Dokl Biochem Biophys ; 488(1): 354-356, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31768859

RESUMO

A mass spectrometric method has been developed for determining the content of dopamine and serotonin derivatives, which allows evaluating the efficiency of their penetration through artificial membranes depending on the structure of their peptide fragment. In this case, the diffusion of dopamine and serotonin derivatives through the membrane occurred as a result of competitive interactions. It was shown which compounds in this mixture more easily penetrate through artificial membranes. It was found that the most promising in terms of overcoming the BBB are Boc-Pro-Srt and Boc-Pro-DOPA.


Assuntos
Dopamina , Membranas Artificiais , Peptídeos , Serotonina , Barreira Hematoencefálica/química , Barreira Hematoencefálica/metabolismo , Dopamina/análogos & derivados , Dopamina/química , Dopamina/farmacocinética , Dopamina/farmacologia , Humanos , Peptídeos/química , Peptídeos/farmacocinética , Peptídeos/farmacologia , Serotonina/análogos & derivados , Serotonina/química , Serotonina/farmacocinética , Serotonina/farmacologia
2.
Domest Anim Endocrinol ; 69: 42-50, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31280025

RESUMO

Peripheral serotonin has been shown to regulate important physiological functions such as energy homeostasis and immunity, particularly in rodent and humans, but its role is poorly understood in livestock species. Herein, we tested the safety and effectiveness of increasing serotonin bioavailability in preweaned dairy calves by oral supplementation of a serotonin precursor (5-hydroxytryptophan, 5-HTP) or a serotonin reuptake inhibitor (fluoxetine, FLX). Bull Holstein calves (21 ± 2 d old; N = 24) were fed milk replacer (8 L/d) supplemented with either saline as control (CON, 8 mL/d, n = 8), FLX (40 mg/d, approx. 0.8 mg/kg; n = 8), or 5-HTP (90 mg/d, approx. 1.8 mg/kg; n = 8) for 10 consecutive days in a complete randomized block design. Heart rate (HR), respiration rate, rectal temperature, and health scores were recorded daily. Hip height and body weight were measured at d 1, 5, and 10 relative to initiation of supplementation. Blood samples were collected once before the supplementation period (d 1), during the 10-d supplementation period (daily), and during a 14-d withdrawal period (d 2, 3, 4, 7, and 14 relative to initiation of withdrawal). Cerebrospinal fluid and muscle tissue were collected from a subset of calves (n = 12) that were euthanized after the 10-d supplementation or 14-d withdrawal period. Whole blood serotonin concentrations increased in 5-HTP calves and decreased in FLX calves compared with CON (P < 0.001), indicating that serotonin bioavailability was increased in both groups. Whole blood serotonin concentrations of 5-HTP and FLX calves returned to CON levels after 7 d of withdrawal. All calves grew and were considered healthy throughout the study. In fact, calves fed 5-HTP had higher average daily gain compared with CON (0.87 vs 0.66 ± 0.12 kg/d, P = 0.05). Calves fed FLX had lower HR (P = 0.02) and greater red blood cells and hemoglobin counts on d 10 of supplementation compared with CON (P < 0.01). After the 14-d withdrawal period, FLX was not detected in circulation of FLX calves, but was still present in the muscle tissue. Our results demonstrate that manipulation of the serotonin pathway by supplementing FLX or 5-HTP is a feasible and safe approach in preweaned dairy calves; however, it takes more than 14 d for FLX to be completely withdrawn from the body.


Assuntos
Comportamento Animal/fisiologia , Bovinos/crescimento & desenvolvimento , Fluoxetina/farmacologia , Inibidores de Captação de Serotonina/farmacologia , Serotonina/farmacologia , Animais , Bovinos/sangue , Bovinos/fisiologia , Suplementos Nutricionais , Fezes/química , Fluoxetina/sangue , Fluoxetina/líquido cefalorraquidiano , Fluoxetina/farmacocinética , Serotonina/sangue , Serotonina/farmacocinética , Distribuição Tecidual
3.
Pharmacol Rep ; 69(5): 846-850, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28623708

RESUMO

BACKGROUND: The aim of this experiment was to investigate a long-lasting local anesthetic bupivacaine combined with serotonin at inducing cutaneous antinociception. METHODS: The skin antinociception, characterized by an inhibition of the cutaneous trunci muscle reflex (CTMR) following the pinprick on the dorsal skin of rats, was evaluated. The cutaneous antinociceptive effects of bupivacaine alone, serotonin alone, or bupivacaine co-injected with serotonin in a dose-dependent fashion were constructed, while the drug-drug interactions were evaluated by isobologram. RESULTS: Subcutaneous serotonin, as well as the local anesthetic bupivacaine provoked dose-related cutaneous antinociception. On an equipotent basis (50% effective dose [ED50]), the relative potency was bupivacaine (0.43 [0.37-0.50] µmol)>serotonin (1.27 [1.15-1.40] µmol) (p<0.01). At the equi-anesthetic doses (ED75, ED50 and ED25), the duration of bupivacaine was similar to that of serotonin at producing cutaneous antinociceptive effects. Co-administration of bupivacaine and serotonin displayed a synergistic antinociception. CONCLUSIONS: The preclinical data demonstrated that serotonin is less potent in eliciting cutaneous antinociceptive effects but has the similar duration of action, compared with bupivacaine. We also found a more significant depth of the sensory block with bupivacaine+serotonin than bupivacaine alone.


Assuntos
Anestésicos Locais/farmacologia , Bupivacaína/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Serotonina/farmacologia , Analgesia , Anestesia Local , Anestésicos Locais/administração & dosagem , Anestésicos Locais/farmacocinética , Animais , Bupivacaína/administração & dosagem , Bupivacaína/farmacocinética , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Injeções Subcutâneas , Masculino , Dor/tratamento farmacológico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Serotonina/administração & dosagem , Serotonina/farmacocinética , Agonistas do Receptor de Serotonina/administração & dosagem , Agonistas do Receptor de Serotonina/farmacocinética
4.
Neuropharmacology ; 113(Pt A): 89-99, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27671323

RESUMO

The FDA-approved antidepressant and smoking cessation drug bupropion is known to inhibit dopamine and norepinephrine reuptake transporters, as well as nicotinic acetylcholine receptors (nAChRs) which are cation-conducting members of the Cys-loop superfamily of ion channels, and more broadly pentameric ligand-gated ion channels (pLGICs). In the present study, we examined the ability of bupropion and its primary metabolite hydroxybupropion to block the function of cation-selective serotonin type 3A receptors (5-HT3ARs), and further characterized bupropion's pharmacological effects at these receptors. Mouse 5-HT3ARs were heterologously expressed in HEK-293 cells or Xenopus laevis oocytes for equilibrium binding studies. In addition, the latter expression system was utilized for functional studies by employing two-electrode voltage-clamp recordings. Both bupropion and hydroxybupropion inhibited serotonin-gated currents from 5-HT3ARs reversibly and dose-dependently with inhibitory potencies of 87 µM and 112 µM, respectively. Notably, the measured IC50 value for hydroxybupropion is within its therapeutically-relevant concentrations. The blockade by bupropion was largely non-competitive and non-use-dependent. Unlike its modulation at cation-selective pLGICs, bupropion displayed no significant inhibition of the function of anion-selective pLGICs. In summary, our results demonstrate allosteric blockade by bupropion of the 5-HT3AR. Importantly, given the possibility that bupropion's major active metabolite may achieve clinically relevant concentrations in the brain, our novel findings delineate a not yet identified pharmacological principle underlying its antidepressant effect.


Assuntos
Antidepressivos de Segunda Geração/farmacocinética , Bupropiona/análogos & derivados , Bupropiona/farmacocinética , Receptores 5-HT3 de Serotonina/metabolismo , Antagonistas do Receptor 5-HT3 de Serotonina/farmacocinética , Serotonina/metabolismo , Regulação Alostérica , Animais , Relação Dose-Resposta a Droga , Granisetron/farmacocinética , Células HEK293 , Humanos , Camundongos , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Serotonina/análise , Serotonina/farmacocinética , Xenopus laevis
5.
Cephalalgia ; 37(11): 1017-1025, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27493234

RESUMO

Background Application of inflammatory mediators to the cranial dura has been used as a method to activate and sensitize neurons in the meningeal sensory pathway in preclinical behavioral studies of headache mechanisms. However, the relatively high concentrations and volumes used in these studies raise the question of whether the applied agents might pass through the dura to act directly on central neurons, thus bypassing the dural afferent pathway. Methods We used a radiolabeling approach to quantify the meningeal permeability of two of the inflammatory mediators, 5-HT and PGE2, when applied to the cranial dura as part of an inflammatory mixture used in preclinical headache models. Results Both agents could be detected in samples taken four hours after dural application in the cerebrospinal fluid (CSF) and, in measurements made only for PGE2, in the central nervous system (CNS) as well. Based on our measurements, we made estimates of the CSF and CNS levels that would be attained with the higher concentrations and volumes of 5HT and PGE2 that were exogenously applied in previous pre-clinical headache studies. These estimated levels were comparable to or larger than normal endogenous levels, potentially large enough to have physiological effects. Conclusions The finding that the cranial meninges are permeable to the two tested inflammatory mediators PGE2 and 5-HT raises some uncertainty about whether the behavioral changes observed in prior pre-clinical headache studies with these as well as other agents can be attributed entirely to the activation of dural nociceptors, particularly when the agents are applied at concentrations several orders of magnitude above physiological levels.


Assuntos
Encéfalo/efeitos dos fármacos , Dinoprostona/farmacocinética , Dura-Máter/efeitos dos fármacos , Transtornos de Enxaqueca/induzido quimicamente , Serotonina/farmacocinética , Animais , Modelos Animais de Doenças , Inflamação/induzido quimicamente , Masculino , Neurônios/efeitos dos fármacos , Permeabilidade , Ratos Sprague-Dawley
6.
Actas esp. psiquiatr ; 45(supl.1): 16-36, 2017. tab
Artigo em Espanhol | IBECS | ID: ibc-172027

RESUMO

Se consideran Trastornos de la Conducta Alimentaria (TCA) a una serie de entidades nosológicas diferenciadas que tienen como nexo común una alteración continuada en la ingesta o bien en la conducta relacionada con la ingesta. Dentro de dicha clasificación destacan los siguientes trastornos: Anorexia Nerviosa (AN) y Bulimia Nerviosa (BN). La AN es un trastorno de curso crónico caracterizado principalmente por una negativa o disminución de la ingesta acompañado de una distorsión de la imagen corporal con el consecuente miedo intenso a la ganancia de peso. Se estima una prevalencia vital en la adolescencia de dicho trastorno de aproximadamente el 0,5-1%1. En la BN la presencia de atracones de comida y la posterior conducta compensatoria (en forma de ejercicio intenso, uso de laxantes, diuréticos...) es lo que prima en el paciente. La prevalencia se estima entre un 2 y un 4% en mujeres jóvenes, iniciándose generalmente en etapas algo posteriores que la AN. Se cree que en su patogenia influyen factores biológicos, psicológicos y ambientales así como una cierta vulnerabilidad genética. Existen distintos tratamientos con eficacia avalada por parte de literatura científica, tanto terapias biológicas como psicológicas, a pesar de ello, nos encontramos con una efectividad parcial de dichas terapias siendo necesaria la búsqueda de nuevas dianas así como de nuevos tratamiento. Aunque la etiopatogenia de los TCA no esté clara, algunas de las disfunciones neurobiológicas encontradas permitirían considerar que la dieta y la administración de nutrientes podría ser relevante en el tratamiento de estos trastornos. Proponemos en este artículo una revisión de nuevos tratamientos enfocados al déficit nutricional (AU)


Eating disorders (EDs) are a series of differentiated nosological entities sharing the common link of a continuous alteration in food intake or in food intake-related behavior. Within this classification, the following disorders are noteworthy: anorexia nerviosa (AN) and bulimia nerviosa (BN). Anorexia nervosa is a chronic disorder characterized mainly by negative or decreased food intake accompanied by a distortion of body image and intense accompanying fear of weight gain. The estimated vital prevalence of this disorder in adolescence is approximately 0.5%-1%.1 The primary feature of BN is the presence of binge eating accompanied by compensatory behavior (in the form of intense exercise and the use of laxatives and diuretics, etc.). The prevalence of BN is estimated to be between 2% and 4% in young women, and it generally starts at somewhat later stages than AN. It is believed that biological, psychological, and environmental factors, as well as genetic vulnerability, influence the pathogenesis of EDs. A variety of therapies exist, both biological and psychological, whose effectiveness is supported by the scientific literature. Nonetheless, we find these therapies only partially effective and new targets as well as new treatments should be sought. Although the etiopathogenesis of EDs is unclear, some of the neurobiological dysfunction found suggests that diet and nutrient supplementation could be relevant in their treatment. We review in this article new treatments focusing on nutritional déficits (AU)


Assuntos
Humanos , Transtornos da Alimentação e da Ingestão de Alimentos/dietoterapia , Anorexia Nervosa/dietoterapia , Bulimia Nervosa/dietoterapia , Ácidos Graxos Ômega-3/uso terapêutico , Triptofano/uso terapêutico , Neurotransmissores/fisiologia , Serotonina/farmacocinética , Dopaminérgicos/farmacocinética , Predisposição Genética para Doença , Desnutrição/dietoterapia , Complexo Vitamínico B/uso terapêutico
7.
Sci Rep ; 6: 24233, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052887

RESUMO

The purpose of this study was to characterize a novel compound, 4-[2-(dimethylamino)-1-(1-hydroxycyclohexyl) ethyl] phenyl 3-nitrophenyl ether, designated LPM580153. We used several well-validated animal models of depression to assess the antidepressant-like activity of LPM580153, followed by a neurotransmitter uptake assay and a corticosterone-induced cell injury model to explore its mechanism of action. In mice, LPM580153 reduced immobility time in the tail suspension test, and in rats subjected to chronic unpredictable mild stress it reversed reductions in body weight gain and ameliorated anhedonia. The neurotransmitter uptake assay results demonstrated that LPM580153 inhibited the uptake of serotonin, norepinephrine and dopamine. Furthermore, LPM580153 protected the SH-SY5Y cells against the cytotoxic activity of corticosterone, an action that might be related to the role of LPM580153 in increasing the protein levels of BDNF, p-ERK1/2, p-AKT, p-CREB and p-mTOR. Together, these findings indicate that LPM580153 is a novel triple reuptake inhibitor with robust antidepressant-like effects.


Assuntos
Anedonia/efeitos dos fármacos , Antidepressivos/farmacologia , Cicloexanóis/farmacologia , Depressão/prevenção & controle , Inibidores da Captação de Neurotransmissores/farmacologia , Fenetilaminas/farmacologia , Animais , Antidepressivos/química , Transporte Biológico/efeitos dos fármacos , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corticosterona/farmacologia , Cicloexanóis/química , Depressão/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Dopamina/farmacocinética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Masculino , Camundongos , Estrutura Molecular , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Inibidores da Captação de Neurotransmissores/química , Norepinefrina/metabolismo , Norepinefrina/farmacocinética , Fenetilaminas/química , Ratos Sprague-Dawley , Serotonina/metabolismo , Serotonina/farmacocinética , Ganho de Peso/efeitos dos fármacos
8.
Behav Brain Res ; 307: 73-83, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27036647

RESUMO

Chronic unpredictable mild stress (CUMS) elicits aspects of cognitive and behavioral alterations that can be used to model comparable aspects of depression in humans. The aim of the present study was to investigate the antidepressant-like potential of 7-fluoro-1,3-diphenylisoquinoline-1-amine (FDPI), a novel isoquinoline compound, in CUMS, a model that meets face, construct and predictive criteria for validity. Swiss mice were subjected to different stress paradigms daily for a period of 35 days to induce the depressive-like behavior. The animals received concomitant FDPI (0.1 and 1mg/kg, intragastric) or paroxetine (8mg/kg, intraperitoneal) and CUMS. The behavioral tests (splash test, tail suspension test, modified forced swimming test and locomotor activity) were performed. The levels of cytokines, corticosterone and adrenocorticotropic (ACTH) hormones were determined in the mouse prefrontal cortex and serum. The synaptosomal [(3)H] serotonin (5-HT) uptake, nuclear factor (NF)-κB, tyrosine kinase receptor (TrkB) and pro-brain-derived neurotrophic factor (BDNF) levels were determined in the mouse prefrontal cortex. CUMS induced a depressive-like behavior in mice, which was demonstrated in the modified forced swimming, tail suspension and splash tests. FDPI at both doses prevented depressive-like behavior induced by CUMS, without altering the locomotor activity of mice. FDPI at the highest dose prevented the increase in the levels of NF-kB, pro-inflammatory cytokines, corticosterone and ACTH and modulated [(3)H]5-HT uptake and the proBDNF/TrkB signaling pathway altered by CUMS. The present findings demonstrated that FDPI elicited an antidepressant-like effect in a model of stress-induced depression.


Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Depressão/etiologia , Quinolinas/uso terapêutico , Estresse Psicológico/complicações , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Antidepressivos/farmacologia , Citocinas/metabolismo , Depressão/metabolismo , Modelos Animais de Doenças , Asseio Animal/efeitos dos fármacos , Elevação dos Membros Posteriores/psicologia , Hormônios/metabolismo , Locomoção , Masculino , Camundongos , Paroxetina/uso terapêutico , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Quinolinas/farmacologia , Serotonina/farmacocinética , Natação/psicologia , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo , Trítio/farmacocinética
9.
Neuropharmacology ; 101: 68-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26362361

RESUMO

In recent years, use of psychoactive synthetic stimulants has grown rapidly. 5-(2-Aminopropyl)indole (5-IT) is a synthetic drug associated with a number of fatalities, that appears to be one of the newest 3,4-methylenedioxymethamphetamine (MDMA) replacements. Here, the monoamine-releasing properties of 5-IT, its structural isomer 6-(2-aminopropyl)indole (6-IT), and MDMA were compared using in vitro release assays at transporters for dopamine (DAT), norepinephrine (NET), and serotonin (SERT) in rat brain synaptosomes. In vivo pharmacology was assessed by locomotor activity and a functional observational battery (FOB) in mice. 5-IT and 6-IT were potent substrates at DAT, NET, and SERT. In contrast with the non-selective releasing properties of MDMA, 5-IT displayed greater potency for release at DAT over SERT, while 6-IT displayed greater potency for release at SERT over DAT. 5-IT produced locomotor stimulation and typical stimulant effects in the FOB similar to those produced by MDMA. Conversely, 6-IT increased behaviors associated with 5-HT toxicity. 5-IT likely has high abuse potential, which may be somewhat diminished by its slow onset of in vivo effects, whereas 6-IT may have low abuse liability, but enhanced risk for adverse effects. Results indicate that subtle differences in the chemical structure of transporter ligands can have profound effects on biological activity. The potent monoamine-releasing actions of 5-IT, coupled with its known inhibition of MAO A, could underlie its dangerous effects when administered alone, and in combination with other monoaminergic drugs or medications. Consequently, 5-IT and related compounds may pose substantial risk for abuse and serious adverse effects in human users.


Assuntos
Encéfalo/efeitos dos fármacos , Indóis/farmacologia , Proteínas de Transporte de Neurotransmissores/metabolismo , Inibidores da Captação Adrenérgica/farmacologia , Animais , Estimulantes do Sistema Nervoso Central/farmacologia , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Atividade Motora/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Proteínas de Transporte de Neurotransmissores/genética , Ratos , Ratos Sprague-Dawley , Serotonina/farmacocinética , Fatores de Tempo , Trítio/farmacocinética
10.
Sci Rep ; 5: 17324, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26616662

RESUMO

Accumulating evidence shows indigenous gut microbes can interact with the human host through modulation of serotonin (5-HT) signaling. Here we investigate the impact of the probiotic Escherichia coli Nissle 1917 (EcN) on 5-HT signalling in gut tissues. Ex-vivo mouse ileal tissue sections were treated with either EcN or the human gut commensal MG1655, and effects on levels of 5-HT, precursors, and metabolites, were evaluated using amperometry and high performance liquid chromatography with electrochemical detection (HPLC-EC). Exposure of tissue to EcN cells, but not MG1655 cells, was found to increase levels of extra-cellular 5-HT. These effects were not observed when tissues were treated with cell-free supernatant from bacterial cultures. In contrast, when supernatant recovered from untreated ileal tissue was pre-incubated with EcN, the derivative cell-free supernatant was able to elevate 5-HT overflow when used to treat fresh ileal tissue. Measurement of 5-HT precursors and metabolites indicated EcN also increases intracellular 5-HTP and reduces 5-HIAA. The former pointed to modulation of tryptophan hydroxylase-1 to enhance 5-HT synthesis, while the latter indicates an impact on clearance into enterocytes through SERT. Taken together, these findings show EcN is able to enhance 5-HT bioavailability in ileal tissues through interaction with compounds secreted from host tissues.


Assuntos
Escherichia coli/fisiologia , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Serotonina/metabolismo , Animais , Disponibilidade Biológica , Espaço Extracelular/metabolismo , Ácidos Graxos/metabolismo , Masculino , Camundongos , Modelos Biológicos , Serotonina/farmacocinética , Transmissão Sináptica
12.
Int J Neuropsychopharmacol ; 17(11): 1737-50, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24833265

RESUMO

Mouse strain differences in immobility and in sensitivity to antidepressants have been observed in the forced swimming test (FST) and the tail suspension test (TST). However, the neurotransmitter systems and neural substrates that contribute to these differences remain unknown. To investigate the role of the hippocampal serotonin transporter (5-HTT), we measured baseline immobility and the immobility responses to fluoxetine (FLX) in the FST and the TST in male CD-1, C57BL/6, DBA and BALB/c mice. We observed strain differences in baseline immobility time, with CD-1 mice showing the longest and DBA mice showing the shortest. In contrast, DBA and BALB/c mice showed the highest sensitivity to FLX, whereas CD-1 and C57BL/6 mice showed the lowest sensitivity. Also we found strain differences in both the total 5-HTT protein level and the membrane-bound 5-HTT level (estimated by V max) as follows: DBA>BALB/c>CD-1=C57BL/6. The uptake efficiency of the membrane-bound 5-HTT (estimated by 1/K m) was highest in DBA and BALB/c mice and lowest in CD-1 and C57BL/6 mice. A correlation analysis of subregions within the hippocampus revealed that immobility time was negatively correlated with V max and positively correlated with K m in the hippocampus. Therefore a higher uptake capacity of the membrane-bound 5-HTT in the hippocampus was associated with lower baseline immobility and greater sensitivity to FLX. These results suggest that alterations in hippocampal 5-HTT activity may contribute to mouse strain differences in the FST and the TST.


Assuntos
Hipocampo/metabolismo , Resposta de Imobilidade Tônica/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Estatística como Assunto , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Fluoxetina/farmacologia , Elevação dos Membros Posteriores , Hipocampo/efeitos dos fármacos , Resposta de Imobilidade Tônica/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Cintilografia , Serotonina/metabolismo , Serotonina/farmacocinética , Inibidores de Captação de Serotonina/farmacologia , Especificidade da Espécie , Natação/psicologia , Sinaptossomos/diagnóstico por imagem , Sinaptossomos/efeitos dos fármacos , Trítio/farmacocinética
13.
IEEE Trans Biomed Eng ; 61(4): 1054-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24658230

RESUMO

Multiscale computational models can provide systemic evaluation and prediction of neuropharmacological drug effects. To date, little computational modeling work has been done to bridge from intracellular to neuronal circuit level. A complex model that describes the intracellular dynamics of the presynaptic terminal of a serotonergic neuron has been previously proposed. By systematically perturbing the model's components, we identify the slow and fast dynamical components of the model, and the reduced slow or fast mode of the model is computationally significantly more efficient with accuracy not deviating much from the original model. The reduced fast-mode model is particularly suitable for incorporating into neurobiologically realistic spiking neuronal models, and hence for large-scale realistic computational simulations. We also develop user-friendly software based on the reduced models to allow scientists to rapidly test and predict neuropharmacological drug effects at a systems level.


Assuntos
Simulação por Computador , Modelos Neurológicos , Neurotransmissores , Serotonina , Humanos , Neurônios/metabolismo , Neurofarmacologia , Neurotransmissores/metabolismo , Neurotransmissores/farmacocinética , Neurotransmissores/farmacologia , Serotonina/metabolismo , Serotonina/farmacocinética , Serotonina/farmacologia , Biologia de Sistemas
14.
Neuroscience ; 259: 194-202, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24321511

RESUMO

The 20 amino acid (AA) N-terminus of the vesicular monoamine transporter 2 (VMAT2) was examined as a regulator of VMAT2 function. Removal of the first 16 or 19 AAs of the N-terminus resulted in a molecule with reduced ability to sequester [(3)H]-5HT. A glutathione-S-transferase-construct of the N-terminus underwent phosphorylation in the presence of PKC at serines 15 and 18. These putative phosphorylation sites were examined for effects on function. Phospho-mimetic substitution of serines 15 and 18 with aspartate in the full-length VMAT2 resulted in reduced [(3)H]-5HT sequestration and reduced methamphetamine (METH)-stimulated efflux of preloaded [(3)H]-5HT. In contrast, mutation of serines 15 and 18 to alanines maintained intact net substrate sequestration but eliminated METH-stimulated efflux of pre-accumulated [(3)H]-5HT. In summary, these data suggest a model in which the VMAT2 N-terminus regulates monoamine sequestration.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Metanfetamina/farmacologia , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Inibidores da Captação Adrenérgica/farmacocinética , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática , Modelos Biológicos , Mutação/genética , Neuroblastoma , Fosforilação/efeitos dos fármacos , Serotonina/farmacocinética , Tetrabenazina/farmacocinética , Transfecção , Trítio/farmacocinética , Proteínas Vesiculares de Transporte de Monoamina/química , Proteínas Vesiculares de Transporte de Monoamina/genética
15.
Neuropharmacology ; 75: 138-44, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23916479

RESUMO

Iptakalim is an ATP-sensitive potassium channel opener, as well as an α4ß2-containing nicotinic acetylcholine receptor (nAChR) antagonist. Pretreatment with iptakalim diminishes nicotine-induced dopamine (DA) and glutamate release in the nucleus accumbens. This neuropharmacological profile suggests that iptakalim may be useful for treatment of nicotine dependence. Thus, we examined the effects of iptakalim in two preclinical models. First, the impact of iptakalim on the interoceptive stimulus effect of nicotine was evaluated by training rats in a discriminated goal-tracking task that included intermixed nicotine (0.4 mg/kg, SC) and saline sessions. Sucrose was intermittently presented in a response-independent manner only on nicotine sessions. On intervening test days, rats were pretreated with iptakalim (10, 30, 60 mg/kg, IP). Results revealed that iptakalim attenuated nicotine-evoked responding controlled by the nicotine stimulus in a dose-dependent manner. In a separate study, the impact of iptakalim on the reinforcing effects of nicotine was investigated by training rats to lever-press to self-administer nicotine (0.01 mg/kg/infusion) [Dosage error corrected]. Results revealed that pretreatment with iptakalim (1, 3, 6 mg/kg, IV) decreased nicotine intake (i.e., less active lever responding). Neither behavioral effect was due to a non-specific motor effect of iptakalim, nor to an ability of iptakalim to inhibit DA transporter (DAT) or serotonin transporter (SERT) function. Together, these finding support the notion that iptakalim may be an effective pharmacotherapy for increasing smoking cessation and a better understanding of its action could contribute to medication development.


Assuntos
Objetivos , Moduladores de Transporte de Membrana/administração & dosagem , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Propilaminas/administração & dosagem , Animais , Condicionamento Operante/efeitos dos fármacos , Dopamina/farmacocinética , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Interações Medicamentosas , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Autoadministração , Serotonina/farmacocinética , Trítio/farmacocinética
16.
Life Sci ; 93(1): 30-37, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23727352

RESUMO

AIMS: Several studies suggested an association between dysregulation of immune mediators and behavioural, neuroendocrine and neurochemical features of depression. Available data showed that cytokines affect the serotonin transporter (SERT) activity through p38 MAP kinase (MAPK)-dependent mechanisms in some cell lines and mice neurons (Zhu et al., Neuropsychopharmacology, 2006; 31:2121-31). The aim of this study was to investigate the interaction of Interleukin-1ß (IL-1ß) or p38 MAPK with SERT activity in rat brain and cell lines. MAIN METHODS: Synaptosomes or cells were treated with IL-1ß or the p38 MAPK activator anisomycin at different concentrations and end-points and the modulation of SERT activity as Km and Vmax was evaluated. KEY FINDINGS: Treatments with IL-1ß or anisomycin did not affect serotonin uptake and p38 MAPK activation in rat synaptosomes, in contrast to reports in mice (Zhu et al., Neuropsychopharmacology, 2010; 35:2510-20). The same treatments activated p38 MAPK phosphorylation in HeLa cells used as positive controls. Similarly, no changes after anisomycin treatment could be detected in [(3)H]serotonin uptake rate in LLC-PK cells expressing human SERT, although phosphorylated p38 MAPK levels augmented significantly. Direct cytokine release in brain was induced by intracerebroventricular administration of bacterial lipopolysaccaride. Although pro-inflammatory cytokines, such as IL-1ß, IL6, and Tumor Necrosis Factor α, showed significant increases in brain cortex, modulation of SERT activity in term of Km and Vmax was not detected. SIGNIFICANCE: These results imply that the stimulation of serotonin uptake by cytokines may not be a unique and fundamental mechanism in the pathology of depression induced by altered immune response.


Assuntos
Encéfalo/metabolismo , Depressão/fisiopatologia , Comportamento de Doença/fisiologia , Serotonina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Análise de Variância , Animais , Anisomicina/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Citocinas/metabolismo , Depressão/imunologia , Depressão/metabolismo , Ativação Enzimática/fisiologia , Ensaio de Imunoadsorção Enzimática , Células HeLa , Humanos , Interleucina-1beta/farmacologia , Análise dos Mínimos Quadrados , Masculino , Ratos , Ratos Sprague-Dawley , Serotonina/farmacocinética , Sinaptossomos/metabolismo
17.
Neurología (Barc., Ed. impr.) ; 28(4): 212-218, mayo 2013. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-112726

RESUMO

Introducción: Los receptores de la acetilcolina de tipo nicotínico (R-Ach-n) son expresados ampliamente en diferentes regiones del cerebro. Particularmente, la conformación de los subtipos α4β2 y la α7 ha sido involucrada con la organización de diferentes tipos de memoria. Además, debido a su localización, estos pueden controlar la liberación de diferentes tipos de neurotransmisores, así como su participación en la plasticidad sináptica. Métodos: Se conformaron 3 grupos de trabajo, un grupo experimental (E), un grupo control (C) y un grupo testigo (T). Al grupo E se le realizó la lesión farmacológica por vía estereotáxica en la región anteroventral del núcleo del rafe dorsal (NRD) con 1μ/μl de 5,7-dihidroxitriptamina. Al grupo C, se le sometió a cirugía y se le aplicó la solución vehículo y finalmente el grupo T no recibió ningún tratamiento; 20 días después de la cirugía, los animales de los 3 grupos fueron sacrificados por decapitación para el análisis de la expresión de las subunidades, α4 y α7 de los R-Ach-n mediante la técnica de biología molecular. Resultados: La denervación 5-HTérgica a la CPF de la rata modifica la expresión de los receptores α4 y α7 de manera diferencial. La expresión de las subunidades α4 se incrementa, mientras que las subunidades α7 disminuyen. Conclusión: Las diferencias de expresión que tuvieron las 2 subunidades podrían deberse a la localización que presentan. La subunidad α4 se localiza en sitios post sinápticos y podría estar relacionada con cambios post sinápticos adaptativos, en tanto que la de la α7 se localiza en sitios presinápticos, por lo que la lesión y eliminación de fibras 5-HTérgicas en la CPF provoca su disminución (AU)


Introduction: Nicotinic acetylcholine receptors (nAChRs) are widely expressed throughout several brain regions. Formation of the α4β2 and α7 subtypes in particular is involved in the organisation of different types of memory. Furthermore, due to their location, these receptors can control the release of various types of neurotransmitters and contribute to synaptic plasticity. Methods: Rats were divided into three groups, an experimental group (E), a sham-operated group, (S) and an intact group (T). In group E, stereotactic guidance was used to induce a chemical lesion with 1 μ/μL of 5,7-dihydroxytryptamine (5,7-DHT) in the anteroventral part of the dorsal raphe nucleus (DRN). In the sham-operated group (S), animals underwent surgery including delivery of the same excipient solution to the same site. The intact group (T) received no treatment whatsoever. Twenty days after surgery, animals in all groups were euthanised by decapitation to evaluate the expression of α4 and α7 nAChRs by means of molecular biology techniques. Results: 5-HT denervation of the rat PFC differentially modified the expression of α4 and α7 receptors: while α4 receptor expression increased, α7 expression decreased. Conclusion: Expression differences observed between the two subtypes may be due to their separate locations. The α4 subtype is found in postsynaptic locations and may be related to adaptive changes in postsynaptic cells, while the location of α7 is presynaptic. This explains why the lesion and the elimination of 5-HT fibres in the CPF would cause a decrease in α7 expression (AU)


Assuntos
Animais , Ratos , Denervação , Serotonina/farmacocinética , Receptores Colinérgicos/análise , Receptores Nicotínicos/análise , Córtex Pré-Frontal , Subunidades alfa de Fatores de Ligação ao Core/fisiologia , 5,7-Di-Hidroxitriptamina/análise
18.
ACS Chem Neurosci ; 4(1): 161-70, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23336055

RESUMO

The serotonin transporter (SERT), a primary target for many antidepressants, is expressed in the brain and also in peripheral blood cells. Although platelet SERT function is well accepted, lymphocyte SERT function has not been definitively characterized. Due to their small size, platelets often are found in peripheral blood mononuclear cell preparations aimed at isolating lymphocytes, monocytes, and macrophages. The presence of different cells makes it difficult to assign SERT expression and function to specific cell types. Here, we use flow cytometry and IDT307, a monoamine transporter substrate that fluoresces after uptake into cells, to investigate SERT function in lymphocyte and platelet populations independently, as well as simultaneously without prior isolation. We find that murine lymphocytes exhibit temperature-dependent IDT307 transport but uptake is independent of SERT. Lack of measurable SERT function in lymphocytes was corroborated by chronoamperometry using serotonin as a substrate. When we examined rhesus and human mixed blood cell populations, we found that platelets, and not lymphocytes, were primary contributors to SERT function. Overall, these findings indicate that lymphocyte SERT function is minimal. Moreover, flow cytometry, in conjunction with the fluorescent transporter substrate IDT307, can be widely applied to investigate SERT in platelets from populations of clinical significance.


Assuntos
Plaquetas/metabolismo , Leucócitos Mononucleares/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Serotonina/farmacocinética , Animais , Fluorescência , Células HEK293 , Humanos , Camundongos , Inibidores de Captação de Serotonina/farmacologia , Proteínas Vesiculares de Transporte de Monoamina/farmacologia
19.
Bioorg Med Chem ; 20(21): 6344-55, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23022052

RESUMO

A group of spirocyclic tropanyl-Δ(2)-isoxazolines was synthesized exploiting the 1,3-dipolar cycloaddition of nitrile oxides to olefins. Their interaction with the dopamine and serotonin transporters (DAT and SERT, respectively) was evaluated through binding experiments. The majority of the compounds had no inhibitory effects (IC(50) >> 10 µM), while some had an IC(50) value in the range 5-10 µM (8a-c, 10b and 11c on DAT, 12b on SERT). Unexpectedly, one of the tertiary amines under investigation, that is 3'-methoxy-8-methyl-spiro{8-azabicyclo[3.2.1]octane-3,5'(4'H)-isoxazole 7a, was able to enhance at a concentration of 10 µM both [(3)H]citalopram and [(3)H]paroxetine binding to SERT in rat brain homogenate (up to 25%, due to an increase of B(max)) and [(3)H]serotonin uptake (up to 30%) in cortical synaptosomes. This peculiar pharmacological profile of 7a suggests it binds to an allosteric site on SERT, and positions derivative 7a as a very useful tool to investigate SERT machinery.


Assuntos
Citalopram/farmacologia , Isoxazóis/farmacologia , Paroxetina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Serotonina/farmacocinética , Compostos de Espiro/farmacologia , Animais , Sítios de Ligação/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Citalopram/química , Proteínas da Membrana Plasmática de Transporte de Dopamina/antagonistas & inibidores , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Relação Dose-Resposta a Droga , Isoxazóis/síntese química , Isoxazóis/química , Estrutura Molecular , Paroxetina/química , Ratos , Serotonina/química , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
20.
Proc Natl Acad Sci U S A ; 109(29): 11510-5, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22778401

RESUMO

Dopamine and serotonin (5-hydroxytryptamine or 5-HT) are neurotransmitters that are implicated in many psychological disorders. Although dopamine transmission in the brain has been studied extensively in vivo with fast scan cyclic voltammetry, detection of 5-HT using in vivo voltammetric methods has only recently been established. In this work we use two carbon-fiber microelectrodes to simultaneously measure dopamine release in the nucleus accumbens and 5-HT release in the substantia nigra pars reticulata, using a common stimulation in a single rat. We find that 5-HT release is profoundly restricted in comparison with dopamine release despite comparable tissue content levels. Using physiological and pharmacological analysis, we find that 5-HT transmission is mostly sensitive to uptake and metabolic degradation mechanisms. In contrast, dopamine transmission is constrained by synthesis and repackaging. Finally, we show that disruption of serotonergic regulatory mechanisms by simultaneous inhibition of uptake and metabolic degradation can have severe physiological consequences that mimic serotonin syndrome.


Assuntos
Dopamina/metabolismo , Técnicas Eletroquímicas/métodos , Núcleo Accumbens/metabolismo , Serotonina/metabolismo , Substância Negra/metabolismo , Análise de Variância , Animais , Carbono/química , Dopamina/biossíntese , Estimulação Elétrica , Microeletrodos , Inibidores da Monoaminoxidase/farmacologia , Ratos , Ratos Sprague-Dawley , Serotonina/farmacocinética , Inibidores de Captação de Serotonina/farmacologia
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