Expression of miR-133a-5p and ROCK2 in Heart in Methamphetamine-Induced Rats and Intervention of Rhynchophylline.

INTRODUCTION: Rhynchophylline, as a traditional Chinese medicine, was used for the treatment of drug addiction. OBJECTIVE: To investigate miRNAs expression profile in the rat hearts of methamphetamine dependence and the intervention mechanisms of rhynchophylline. MATERIALS AND METHODS: This study detected the expression profile of miRNAs in the methamphetamine-induced rat hearts by microarray and verified the expression of miR-133a-5P and Rho-associated, coiled-coil containing protein kinase 2 (ROCK2) protein. RESULTS: After conditioned place preference training, methamphetamine significantly increased the time spent in the drug-paired compartment, while rhynchophylline and MK-801 could reduce the time. Cluster analysis results of miRNAs showed that compared with the control group, the expression of miR-133a-5p in methamphetamine-induced rat hearts was decreased significantly; rhynchophylline could significantly increase the expression of miR-133a-5p. The result was verified by real-time polymerase chain reaction. The results of target gene predictive software and related research showed that ROCK2 protein may be the target gene of miR-133a-5p. The immunohistochemistry results of heart tissues showed that the expression of ROCK2 protein was significantly upregulated in the methamphetamine group and downregulate in the rhynchophylline group; the difference between the MK-801 group and the methamphetamine group was not significant. The result of western blot was consistent with the immunohistochemistry. CONCLUSION: The active ingredient of Chinese herbal medicine rhynchophylline can effectively inhibit the formation of methamphetamine-dependent conditional place preference (CPP) effect in rats to some extent. MiR-133a-5p may participate in the cardioprotective effects of CPP rats by targeting ROCK2.

Mindfulness-based relapse prevention combined with virtual reality cue exposure for methamphetamine use disorder: Study protocol for a randomized controlled trial.

BACKGROUND: Mindfulness-based relapse prevention (MBRP) is a method that combines cognitive behavioral relapse prevention with mindfulness practice. Research suggests that MBRP can effectively reduce withdrawal/craving in people with substance use disorder (SUD). An important part of MBRP is to practice mindfulness meditation to cope with high-risk situations for relapse, such as stimuli and situations associated with drug taking. Virtual reality cue exposure (VRCE) may be a complementary approach to MBRP as it allows for controlled and graded presentations of various high-risk situations with distal and proximal drug cues. The aim of the study is to investigate the effects of MBRP combined with VRCE, in comparison to MBRP alone or treatment as usual, on craving and emotional responses in people with methamphetamine use disorders. METHOD/DESIGN: The study is a parallel randomized controlled study including 180 participants with methamphetamine use disorder. Three parallel groups will receive 8 weeks of MBRP combined with VRCE, MBRP alone, or treatment as usual, respectively. Craving, virtual cue reactivity, anxiety, depression, emotion regulation, mindfulness and drug-related attention bias will be assessed at pre-treatment, post-treatment, and 3 and 6 months of follow-up. DISCUSSION: This innovative study aims at investigating the effects of MBRP combined with VRCE in people with SUD. The combined intervention may have important clinical implications for relapse prevention due to its ease of application and high cost-effectiveness. This study may also stimulate research on the neuronal and psychological mechanisms of MBRP in substance use disorder. TRIAL REGISTRATION NUMBER: ChiCTR-INR-17013041.

Extended-Release Injectable Naltrexone (XR-NTX) With Intensive Psychosocial Therapy for Amphetamine-Dependent Persons Seeking Treatment: A Placebo-Controlled Trial.

OBJECTIVE: Explore the efficacy of extended-release injectable naltrexone (XR-NTX) for preventing relapse to amphetamine use. METHOD: Clinical trial of 100 amphetamine-dependent, treatment-seeking patients who were randomized to 6 monthly 380 mg doses of XR-NTX or matching placebo before entering intensive outpatient after varying lengths of inpatient treatment in Reykjavik, Iceland. Weekly urine drug tests, retention, and standardized instruments assessed efficacy. RESULTS: Of 169 approached, 100 were randomized. Although amphetamine dependence was the main reason for seeking treatment, three-quarters or more of participants had 1 or more other substance dependencies. Of 51 randomized to XR-NTX, 20 received 4 or more injections; of 49 assigned to placebo, 26 received 4 or more injections. Of the planned 2400 weekly urine drug tests, 1247 were collected (52%); 4% of these were positive for amphetamine, 8% for benzodiazepine, 7% for marijuana, 1% for cocaine, and 1% for opioid. XR-NTX had no effect on amphetamine-positive tests, retention, or other outcomes. Those providing half or more of their tests attended more weeks of treatment than those providing less than half of their tests (m = 10.76 vs 3.31; t (92) = 5.91, P < 0.0001), and 92 participants provided at least 1 test. CONCLUSIONS: Adding XR-NTX to the usual combination of inpatient and intensive outpatient treatment did not reduce amphetamine use. The low prevalence of substance use among collected urine samples, and the association between collected samples and weeks in treatment, was consistent with other studies showing that staying in treatment is associated with better outcomes.

Community-based harm reduction substance abuse treatment with methamphetamine-using men who have sex with men.

Harm reduction approaches endeavor to assist individuals with avoiding the most detrimental consequences of risk taking behaviors, but limited research has documented the outcomes of harm reduction substance abuse treatment. In total, 211 methamphetamine-using men who have sex with men (MSM) enrolled in two outcome studies of substance abuse treatment programs that were implementing an evidence-based, cognitive-behavioral intervention (i.e., the Matrix Model) from a harm reduction perspective. Study 1 (N = 123) examined changes in self-reported substance use, Addiction Severity Index (ASI) composite scores, and HIV care indicators over a 12-month follow-up. Study 2 (N = 88) assessed changes in substance use, sexual risk taking, and HIV care indicators over a 6-month follow-up. Participants in study 1 reported reductions in cocaine/crack use as well as decreases in the ASI drug and employment composite scores. Among HIV-positive participants in study 1 (n = 75), 47 % initiated or consistently utilized anti-retroviral therapy and this was paralleled by significant increases in self-reported undetectable HIV viral load. Study 2 participants reported reductions in methamphetamine use, erectile dysfunction medication use in combination with other substances, and sexual risk-taking behavior while using methamphetamine. Participants in both studies reported concurrent increases in marijuana use. Taken together, these studies are among the first to observe that clients may reduce stimulant use and concomitant sexual risk-taking behavior during harm reduction substance abuse treatment. Randomized controlled trials are needed to examine the differential effectiveness of harm reduction and abstinence-based approaches to substance abuse treatment.

Effect of rhynchophylline on the expression of p-CREB and sc-Fos in triatum and hippocampal CA1 area of methamphetamine-induced conditioned place preference rats.

To explore the effect of rhynchophylline (Rhy) on the expression of p-CREB and c-Fos in the striatum and hippocampal CA1 area of methamphetamine-induced conditioned place preference (CPP) rat, methamphetamine (2 mg/kg) was injected to rats and the conditioned place preference was observed in these rats treated with or without Rhy. An immunohistochemistry assay was used to determine the expression of p-CREB and c-Fos in the striatum and hippocampal CA1 area. Methamphetamine induced significant behavior alteration in CPP, while after pretreatment with rhynchophylline or ketamine, the time of staying in methamphetamine-paired compartment of rats was significantly reduced. Methamphetamine also increased the number of p-CREB positive cells in the striatum and hippocampal CA1 zone, as well as p-Fos positive cells. However, the compound Rhy could attenuate the effect. These findings show that Rhy can suppress the acquisition of CPP in rats induced by methamphetamine and the action may be related with the reduced expression of p-CREB and p-Fos in the striatum and hippocampus.

Partial recovery of brain metabolism in methamphetamine abusers after protracted abstinence.

OBJECTIVE: Methamphetamine is a highly addictive drug of abuse that is neurotoxic to dopamine terminals. The authors recently reported that decreases in dopamine transporters (used as markers of dopamine terminals) in the striatum of methamphetamine abusers recover with protracted abstinence and that relative to comparison subjects, recently detoxified methamphetamine abusers have lower metabolism in the striatum and thalamus. In this study, the authors assessed whether metabolism recovers with protracted abstinence. METHOD: Brain glucose metabolism was measured with positron emission tomography and [18F]fluorodeoxyglucose in five methamphetamine abusers who were evaluated after both a short (<6 months) and protracted (12-17 months) abstinence interval, eight methamphetamine abusers tested only after protracted abstinence, and 11 comparison subjects who were not drug users. RESULTS: Significantly greater thalamic, but not striatal, metabolism was seen following protracted abstinence relative to metabolism assessed after a short abstinence interval, and this increase was associated with improved performance in motor and verbal memory tests. Relative to the comparison subjects, the methamphetamine abusers tested after protracted abstinence had lower metabolism in the striatum (most accentuated in the caudate and nucleus accumbens) but not in the thalamus. CONCLUSIONS: The persistent decreases in striatal metabolism in methamphetamine abusers could reflect long-lasting changes in dopamine cell activity, and decreases in the nucleus accumbens could account for the persistence of amotivation and anhedonia in detoxified methamphetamine abusers. The recovery of thalamic metabolism could reflect adaptation responses to compensate for the dopamine deficits, and the associated improvement in neuropsychological performance further indicates its functional significance. These results suggest that while protracted abstinence may reverse some of the methamphetamine-induced alterations in brain function, other deficits persist.