Blockade of the Dopamine D3 Receptor Attenuates Opioids-Induced Addictive Behaviours Associated with Inhibiting the Mesolimbic Dopamine System / 神经科学通报·英文版

Opioid use disorder (OUD) has become a considerable global public health challenge; however, potential medications for the management of OUD that are effective, safe, and nonaddictive are not available. Accumulating preclinical evidence indicates that antagonists of the dopamine D3 receptor (D3R) have effects on addiction in different animal models. We have previously reported that YQA14, a D3R antagonist, exhibits very high affinity and selectivity for D3Rs over D2Rs, and is able to inhibit cocaine- or methamphetamine-induced reinforcement and reinstatement in self-administration tests. In the present study, our results illustrated that YQA14 dose-dependently reduced infusions under the fixed-ratio 2 procedure and lowered the breakpoint under the progressive-ratio procedure in heroin self-administered rats, also attenuated heroin-induced reinstatement of drug-seeking behavior. On the other hand, YQA14 not only reduced morphine-induced expression of conditioned place preference but also facilitated the extinguishing process in mice. Moreover, we elucidated that YQA14 attenuated opioid-induced reward or reinforcement mainly by inhibiting morphine-induced up-regulation of dopaminergic neuron activity in the ventral tegmental area and decreasing dopamine release in the nucleus accumbens with a fiber photometry recording system. These findings suggest that D3R might play a very important role in opioid addiction, and YQA14 may have pharmacotherapeutic potential in attenuating opioid-induced addictive behaviors dependent on the dopamine system.

Methamphetamine: Mechanism of Action and Chinese Herbal Medicine Treatment for Its Addiction / 中国结合医学杂志

With the proliferation of synthetic drugs, research on the mechanism of action of addictive drugs and treatment methods is of great significance. Among them, methamphetamine (METH) is the most representative amphetamine synthetic drug, and the treatment of METH addiction has become an urgent medical and social problem. In recent years, the therapeutic effects of Chinese herbal medicines on METH addiction have gained widespread attention because of their non-addictiveness, multiple targets, low side effects, low cost, and other characteristics. Previous studies have identified a variety of Chinese herbal medicines with effects on METH addiction. Based on the research on METH in recent years, this article summarizes the mechanism of action of METH as the starting point and briefly reviews the Chinese herbal medicine-based treatment of METH.

Systematic review of N-acetylcysteine in the treatment of addictions

Objective: To conduct the first systematic literature review of clinical trials of N-acetylcysteine (NAC) for the treatment of substance abuse disorders and addictive behaviors. Methods: A search of the MEDLINE, Embase and PsycINFO databases was conducted. The inclusion criteria for the review were clinical trials that used NAC in the treatment of a disorder related to substance use and/or addictive behaviors, limited to texts in English, Spanish, or French. The selected studies were evaluated with respect to type of trial, sample size, diagnostic input, intervention, length of follow-up, outcome variables, and results. Results: Nine studies analyzing a total of 165 patients met the eligibility criteria and were included in qualitative analysis. These studies evaluated the role of NAC in cocaine dependence (three studies), cannabis dependence (two studies), nicotine dependence (two studies), methamphetamine addiction (one study), and pathological gambling (one study). Five of these trials were double-blind, randomized, and placebo-controlled. Conclusions: The studies analyzed suggest a potential role for NAC in the treatment of addiction, especially of cocaine and cannabis dependence. These results are concordant with the hypothesis of the involvement of glutamatergic pathways in the pathophysiology of addiction. .

Changes of Functional MRI Findings in a Patient Whose Pathological Gambling Improved with Fluvoxamine

Legalized gambling is a growing industry, and is probably a factor in the presently increasing prevalence of pathological gambling. We present a case of a 36-year-old pathological gambler who was treated with fluvoxamine, a selective serotonin reuptake inhibitor, and who was assessed by functional MRI before and after drug administration. During activation periods, the pathological gambler was shown cards as stimuli, and fMRI results in several brain regions showed differential effects before and after medication and a maintenance period. This case demonstrates that the treatment response to fluvoxamine in a pathological gambler was observed not only by subjective self-report, but also by objective fMRI results. Therefore, fMRI may be a useful tool in the diagnosis and prediction of treatment response in patients afflicted with pathological gambling.

Craving decrease with topiramate in outpatient treatment for cocaine dependence: an open label trial / Diminuição da fissura com topiramato no tratamento ambulatorial para dependência de cocaína: um ensaio clínico aberto

OBJECTIVE: To evaluate anticraving action and tolerability of topiramate in cocaine user treatment. METHOD: Male users of inhaled cocaine which met criteria for cocaine dependence (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) were selected for outpatient 12-week, open label trial with topiramate; individual dosage ranged between 25-300 mg/day. Main clinical variables were abstinence rate, craving intensity, frequency and duration, adherence, dropouts, side effects and impulsivity measure through Barratt Impulsivity Scale. Patients received assertive strategic counseling for abstinence assistance and medication monitoring evaluation every two weeks. Comparative analysis was made with intention to treat, missing values were replaced (last observation carried forward), and significance level was 5 percent. RESULTS: Adherence to treatment was 57 percent (at least three evaluations), 32 percent dropped out (one evaluation). There were no severe side effects. Negative test average was 25.4 percent (31.2). Significant reduction in craving intensity and duration was observed in 25 percent of the sample. No statistical significant reduction in craving frequency was observed in 7.1 percent. Increase in frequency was observed in 10.7 percent and 82.1 percent did not present any variation. No significant statistical variations in Barratt Impulsivity Scale or in the total score were found in the final evaluation when compared to baseline. CONCLUSION: More randomized placebo-controlled trials with topiramate for cocaine dependants should be performed to evaluate preliminary evidence.

OBJETIVO: Avaliar a ação anticraving e tolerabilidade do topiramato em usuários de cocaína. MÉTODO: Homens usuários de cocaína inalada que preenchiam critérios para dependência de cocaína (Manual Diagnóstico e Estatístico de Desordens Mentais, quarta edição) foram selecionados para 12 semanas de tratamento ambulatorial, em ensaio clínico aberto com topiramato; dosagens escalonadas entre 25-300 mg/dia. As principais variáveis clínicas foram taxa de abstinência, intensidade, freqüência e duração do craving, aderência, perdas, efeitos colaterais e impulsividade medida por meio da Escala de Impulsividade Barratt. Os pacientes receberam estratégias assertivas de aconselhamento para manutenção da abstinência e monitoramento da medicação avaliada a cada duas semanas. Análises comparativas foram feitas com intenção de tratar, valores perdidos foram substituídos (última observação carregada ao final) e o nível de significância de 5 por cento. RESULTADOS: A aderência ao tratamento foi de 57 por cento (pelo menos três avaliações), 32 por cento de perdas (uma avaliação). Não houve efeitos colaterais graves. A média de testes negativos foi 25,4 por cento (31,2). Significante redução na intensidade e duração do craving foi observada em 25 por cento da amostra. Nenhuma redução significativa na freqüência do craving foi observada em 7,1 por cento. Aumento na freqüência foi observado em 10,7 por cento e 82,1 por cento não apresentaram nenhuma variação. Nenhuma variação estatisticamente significativa na Escala de Impulsividade Barratt ou na pontuação total foi encontrada no final da avaliação quando comparado à inicial. CONCLUSÃO: Mais ensaios clínicos placebo-controlados com o topiramato para dependentes de cocaína deveriam ser conduzidos a fim de avaliar a evidência preliminar.

Baclofen in maintenance treatment of opioid dependence: a randomized double-blind clinical trial with placebo-controlled

This project was aimed to evaluate the efficacy of baclofen in keeping opioid dependents in maintenance treatment and in reduction of their opioid use. It also assessed its superiority over placebo. In this double blind experimental study, 40 patients with the diagnosis of opioid dependence [DSM- IV based criteria] were inserted randomly in two groups following the detoxification phase. In one group, 20 patients took baclofen [60 mg daily in three divided doses] and in the other one, 20 patients took placebo for a total of 12 weeks. The primary measuring factors included retention of patients in maintenance treatment and positive urine analysis. The project's data were analyzed via statistical Mann-Whitney and chi-square tests. The retention of patients in treatment was significantly more in baclofen group than the placebo group. baclofen group patients exhibited less opioid withdrawal and depressive symptoms than the placebo group. There were no significant differences between the two groups in terms of the rate of positive urine analysis, intensity of craving for opioid use, medication side effects, and the average days of opioid and alcohol consumption during treatment. Baclofen is considerably superior to placebo in keeping the patients in treatment and also in reduction of opioid withdrawal and depressive symptoms