Êxtase (MDMA): efeitos farmacológicos e tóxicos, mecanismo de ação e abordagem clínica

BACKGROUND: The consumption of the amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) by young people increased in the past years. OBJECTIVES: To conduct a literature review on the pharmacology of MDMA and particularly with respect to the putative mechanism of action implicated in the acute and long-term toxicity and neurotoxic effects. METHODS: A literature review using the key words: 3,4-methylenedioxymethamphetamine, ecstasy, neurotoxicity, intoxication, abuse drugs was performed in the databases MEDLINE and LILACS. The search covered all articles published between 1985 and 2007. RESULTS: There were still many unanswered questions regarding the pharmacology of ecstasy and the pathophysiology of its toxic effects. The fundamental mechanism of action is insufficient to explain all effects induced by the drug. The exact mechanism responsible for mediating the toxic effects of MDMA on 5-HT neurons remain to be elucidated. DISCUSSION: There is limited information in published literature about the underlying pharmacology and mechanism of action that could account for the neurotoxic and other phathophysiological effect of MDMA.CONTEXTO: O 3,4-metilenodioximetanfetamina (MDMA, êxtase) é um derivado da anfetamina, cujo consumo por jovens tem aumentado. OBJETIVOS: Conduzir uma revisão de literatura sobre os aspectos farmacológicos e fisiopatológicos do MDMA, incluindo o mecanismo de ação que possa explicar os efeitos neurotóxicos e a toxicidade aguda e a longo prazo. MÉTODOS: Revisão da literatura usando as palavras-chave: 3,4-methylenedioxymethamphetamine, ecstasy, neurotoxicity, intoxication, drug abuse, por intermédio do MEDLINE e LILACS. A busca incluiu todos os artigos publicados no período entre 1985 e 2007. RESULTADOS: Ainda existem muitas questões sem respostas sobre a farmacologia do êxtase e a fisiopatologia dos efeitos tóxicos dessa substância. A simples descrição do mecanismo de ação é insuficiente para explicar todos os efeitos induzidos pelo êxtase. O mecanismo exato responsável por mediar os efeitos tóxicos do MDMA sobre os neurônios da serotonina precisa ser elucidado. CONCLUSÕES: Existem poucas informações na literatura sobre a farmacologia e o mecanismo de ação do MDMA que possam explicar os efeitos neurotóxicos e outros efeitos fisiopatológicos. São necessários mais estudos para que o profissional de saúde possa obter informações e conhecimentos a fim de combater os efeitos terríveis do êxtase na população jovem vulnerável

Time course of the effects of lipopolysaccharide on prepulse inhibition and brain nitrite content in mice

AbstractThe systemic administration of lipopolysaccharide (LPS) induces time-dependent behavioral alterations, which are related to sickness behavior and depression. The time-course effects of LPS on prepulse inhibition (PPI) remain unknown. Furthermore, the time-dependent effects of LPS on central nitrite content had not been investigated. Therefore, we studied alterations induced by single LPS (0.5mg/kg, i.p.) administration to mice on parameters, such as PPI, depressive- and anxiety-like behaviors, working memory, locomotor activity and motor coordination, 1.5 and 24h post-LPS administration. IL-1β and TNFα in the blood and brain as well as brain nitrite levels were evaluated in the prefrontal cortex (PFC), hippocampus (HC) and striatum (ST). An overall hypolocomotion was observed 1.5h post-LPS, along with depressive-like behaviors and deficits in working memory. Increments in IL-1β content in plasma and PFC, TNFα in plasma and decreases in nitrite levels in the ST and PFC were also verified. Twenty-four hours post-LPS treatment, depressive-like behaviors and working memory deficits persisted, while PPI levels significantly reduced along with increases in IL-1β content in the PFC and a decrease in nitrite levels in the HC, ST and PFC. Our data demonstrate that a delayed increase (i.e., 24h post-LPS) in PPI levels ensue, which may be useful behavioral parameter for LPS-induced depression. A decrease in nitrergic neurotransmission was associated with these behavioral findings

Reações adversas causadas por fármacos que atuam no sistema nervoso: análise de registros de um centro de farmacovigilância do Brasil

BACKGROUND: The morbi-mortality by the use of medicines is a major health problem. The drug adverse reactions may result in death, increased hospitalizations and healthcare costs. OBJECTIVES: Describe and analyze reports of suspected adverse reactions caused by drugs that act on the nervous system (SN-ADR), registered in the database of the Pharmacovigilance Centre of Ceará, from January 1997 to March 2008. METHODS: All the NS-ADRs were classified according to criteria of the World Health Organization. The causality between the drug administered and the adverse reaction was established, as well as the analysis regarding to the severity of the reaction. RESULTS: The Centre recorded 176 notifications of RAM-SN. The most of the reactions occurred in the hospital. The main reporter was the pharmacist. All the RAM-SN were classified as possible (n = 110), probable (n = 37) and definite (n = 17). With regard to severity, the NS-ADRs were considered: light (n = 21), moderate (n = 127), serious (n = 15) and fatal (n = 1). The fatal case was reported by physician, and involved anesthetic drugs. In general the adverse reactions observed were caused predominantly by analgesics, anesthetics and antiepileptics. DISCUSSION: The data demonstrate the potential values of accessing to a local system of pharmacovigilance to report possible risks with the use of nervous system drugs.CONTEXTO: A morbimortalidade por uso de medicamentos é um grande problema de saúde. As reações adversas a medicamentos podem resultar em óbito, aumento de internações hospitalares e dos custos com a saúde. OBJETIVOS: Descrever e analisar as notificações de suspeitas de reações adversas causadas por medicamentos que atuam no sistema nervoso (RAM-SN), registradas no Centro de Farmacovigilância do Ceará, de janeiro de 1997 a março de 2008. MÉTODOS: As RAM-SN foram classificadas segundo os critérios da Organização Mundial da Saúde. Uma relação de causalidade entre o fármaco administrado e a reação adversa identificada foi realizada, bem como a análise da reação quanto à gravidade. RESULTADOS: Foram registradas 176 notificações de RAM-SN. A maioria (n = 145; 82,4%) ocorreu no ambiente hospitalar. O principal notificador foi o farmacêutico. As RAM-SN foram classificadas como: possíveis (n = 110), prováveis (n = 37) e definidas (n = 17). Quanto à gravidade, foram consideradas: leves (n = 21), moderadas (n = 127), graves (n = 15) e fatais (n = 1). O caso fatal foi notificado por médico e envolveu medicamentos anestésicos. Geralmente, as reações adversas observadas foram causadas predominantemente por analgésicos, anestésicos e antiepilépticos. DISCUSSÃO: Os dados demonstram o valor potencial de se ter acesso a sistemas de farmacovigilância local para registrar possíveis riscos com o uso de fármacos

Effects of botulinum toxin type A for spastic foot in post-stroke patients enrolled in a rehabilitation program

The objective of this study was to evaluate the effects of botulinum toxin type A (BTX-A) on spastic foot in stroke patients in a rehabilitation program. Method: Hemiparetic stroke patients (n=21) enrolled in a rehabilitation program were divided into two groups. The first group (n=11) received a total of 300UI BTX-A, and the second group (n=10) received 100 UI BTX-A. All patients were assessed at baseline and 2, 4, 8 and 12 weeks after injection for Modified Ashworth Score, time walking 10 meters, and the Functional Independence Measure (mFIM) motor score. Results: The higher-dose group exhibited a significant improvement in spasticity, and both groups showed an improvement in time walking 10 meters and mFIM, with no significant differences between them. Conclusions: Our findings suggest that gains in gait velocity and functional independence were not correlated to BTX-A dose

Esquizofrenia: uma doença inflamatória?

OBJETIVO: Neste estudo, o objetivo foi revisar o papel de um possível processo inflamatório na gênese da esquizofrenia. MÉTODO: Foram selecionados os trabalhos publicados em revistas indexadas nas bases de dados Lilacs e MedLine, sob os unitermos "esquizofrenia", "inflamação" e "estresse oxidativo", nos últimos 10 anos até dezembro de 2009, nos idiomas inglês e português. Foram excluídos os artigos que tratavam de aspectos fisiopatológicos da doença fora do interesse da psiquiatria. RESULTADOS: Sessenta e um artigos foram selecionados. Doze abordavam o envolvimento do estresse oxidativo na esquizofrenia, nove tratavam de alterações no sistema imunológico de pacientes esquizofrênicos, dezesseis da infecção pré-natal como desencadeador da doença e sete mostravam a ação antioxidante e anti-inflamatória de fármacos antipsicóticos. CONCLUSÃO: Os estudos enfatizam o envolvimento do sistema imunológico (isto é, interleucinas e ação anti-inflamatória dos antipsicóticos), das infecções, do estresse oxidativo e da função mitocondrial na fisiopatologia da esquizofrenia. Portanto, esses novos achados são importantes para a melhor compreensão e, consequentemente, a elaboração de terapias mais específicas e eficazes no combate dessa doença mental

Reações adversas causadas por fármacos que atuam no sistema nervoso: análise de registros de um centro de farmacovigilância do Brasil Adverse reaction caused by drugs acting in nervous system: records analysis of a farmacovigilance center in Brazil

CONTEXTO: A morbimortalidade por uso de medicamentos é um grande problema de saúde. As reações adversas a medicamentos podem resultar em óbito, aumento de internações hospitalares e dos custos com a saúde. OBJETIVOS: Descrever e analisar as notificações de suspeitas de reações adversas causadas por medicamentos que atuam no sistema nervoso (RAM-SN), registradas no Centro de Farmacovigilância do Ceará, de janeiro de 1997 a março de 2008. MÉTODOS: As RAM-SN foram classificadas segundo os critérios da Organização Mundial da Saúde. Uma relação de causalidade entre o fármaco administrado e a reação adversa identificada foi realizada, bem como a análise da reação quanto à gravidade. RESULTADOS: Foram registradas 176 notificações de RAM-SN. A maioria (n = 145; 82,4%) ocorreu no ambiente hospitalar. O principal notificador foi o farmacêutico. As RAM-SN foram classificadas como: possíveis (n = 110), prováveis (n = 37) e definidas (n = 17). Quanto à gravidade, foram consideradas: leves (n = 21), moderadas (n = 127), graves (n = 15) e fatais (n = 1). O caso fatal foi notificado por médico e envolveu medicamentos anestésicos. Geralmente, as reações adversas observadas foram causadas predominantemente por analgésicos, anestésicos e antiepilépticos. DISCUSSÃO: Os dados demonstram o valor potencial de se ter acesso a sistemas de farmacovigilância local para registrar possíveis riscos com o uso de fármacos.<br>BACKGROUND: The morbi-mortality by the use of medicines is a major health problem. The drug adverse reactions may result in death, increased hospitalizations and healthcare costs. OBJECTIVES: Describe and analyze reports of suspected adverse reactions caused by drugs that act on the nervous system (SN-ADR), registered in the database of the Pharmacovigilance Centre of Ceará, from January 1997 to March 2008. METHODS: All the NS-ADRs were classified according to criteria of the World Health Organization. The causality between the drug administered and the adverse reaction was established, as well as the analysis regarding to the severity of the reaction. RESULTS: The Centre recorded 176 notifications of RAM-SN. The most of the reactions occurred in the hospital. The main reporter was the pharmacist. All the RAM-SN were classified as possible (n = 110), probable (n = 37) and definite (n = 17). With regard to severity, the NS-ADRs were considered: light (n = 21), moderate (n = 127), serious (n = 15) and fatal (n = 1). The fatal case was reported by physician, and involved anesthetic drugs. In general the adverse reactions observed were caused predominantly by analgesics, anesthetics and antiepileptics. DISCUSSION: The data demonstrate the potential values of accessing to a local system of pharmacovigilance to report possible risks with the use of nervous system drugs

Tyramine exerts hypolipidemic and anti-obesity effects in vivo

Obesity and dyslipidemia are conditions often associated with cardiovascular risk, inflammation, oxidative stress, and death. Thus, a new approach has been highlighted to promote research and development of pharmacological tools derived from natural sources. Among the most widely studied groups of substances, polyphenols such as tyramine stand out. This study investigated hypolipidemic and anti-obesity properties of tyramine. Oral toxicity evaluation, models of dyslipidemia and obesity were used. To induce dyslipidemia, Poloxamer-407 (P-407) was administered intraperitoneally. In the hypercholesterolemic and obesity model, specific diet and oral tyramine were provided. After 24h of P-407 administration, tyramine 2 mg/kg (T2) decreased triglycerides (TG) (2057.0 ± 158.5 mg/dL vs. 2838 ± 168.3 mg/dL). After 48h, TG were decreased by T2 (453.0 ± 35.47 vs. 760.2 ± 41.86 mg/dL) and 4 mg/kg (T4) (605.8 ± 26.61 760.2 ± 41.86 mg/dL). T2 reduced total cholesterol (TC) after 24h (309.0 ± 11.17 mg/dL vs. 399.7 ± 15.7 mg/dL); After 48h, 1 mg/kg (T1) (220.5 ± 12.78 mg/dL), T2 (205.8 ± 7.1 mg/dL) and T4 (216.8 ± 12.79 mg/dL), compared to P-407 (275.5 ± 12.1 mg/dL). The treatment decreased thiobarbituric acid reactive substances and nitrite in liver, increased superoxide dismutase, reduced the diet-induced dyslipidemia, decreasing TC around 15%. Tyramine reduced body mass, glucose, and TC after hypercaloric feed. Treatment with 5 mg/L (0.46 ± 0.04 ng/dL) and 10 mg/L (0.44 ± 0.02 ng/dL) reduced plasma insulin (1.18 ± 0.23 ng/dL). Tyramine increased adiponectin at 5 mg/L (1.02 ± 0.02 vs. 0.83 ± 0.02 ng/mL) and 10mg/L (0.96 ± 0.04 ng/mL). In conclusion, tyramine has low toxicity in rodents, has antioxidant effect, reduces plasma triglycerides and cholesterol levels. However, further studies should be conducted in rodents and non-rodents to better understand the pharmacodynamic and pharmacokinetic properties of tyramine