Methamphetamine Research Articles

Adolescent alcohol binge drinking and withdrawal: behavioural, brain GFAP-positive astrocytes and acute methamphetamine effects in adult female rats.

Alcopop beverages are generally the first alcoholic beverage that young females drink which contain high levels of sugar and alcohol. The over-consumption of these drinks may encourage alcohol co-administration with methamphetamine (METH) impacting on drinking behaviour and glial function. The aims of this study were to evaluate the effect of adolescent binge alcohol exposure on consumption level, anxiety-like behaviour, cross-sensitization with METH and on astrocyte expression in reward related brain regions. Adolescent female Sprague-Dawley rats had daily 1-hour oral alcohol consumption of alcopop (ALCP; with sucrose) or ethanol-only (ETOH; without sucrose), transitioned from 5 to 15% (v/v) ethanol content for 34 days. Water and sucrose groups act as controls. During alcohol withdrawal, rats were tested for anxiety on the elevated plus maze (EPM) and locomotor activity following saline or METH (1mg/kg i.p) treatment. Brains were then collected to assess astrocyte immunofluorescence for glial fibrillary acidic protein (GFAP) in reward-related brain regions. Rats pretreated with 5% ALCP consumed significantly more volume and ethanol intake when compared to 5% EtOH rats. Both ALCP and EtOH groups had a higher preference ratio for 5% than 15% alcohol solutions and ALCP rats had greater ethanol intake at 15% than EtOH rats. Alcohol withdrawal showed no significant differences between groups on anxiety, METH cross-sensitization effects or GFAP intensity in the regions studied. Overall, the addition of sucrose to alcoholic solutions encouraged female rats to consume larger volumes and greater ethanol intake compared to ethanol-only solutions, yet did not have long lasting effects on behaviour and astrocytes.

Identification of the circRNA-miRNA-mRNA network for treating methamphetamine-induced relapse and behavioral sensitization with cannabidiol.

This study aims to investigate the pharmacological effects and the underlying mechanism of cannabidiol (CBD) on methamphetamine (METH)-induced relapse and behavioral sensitization in male mice. The conditioned place preference (CPP) test with a biased paradigm and open-field test were used to assess the effects of CBD on METH-induced relapse and behavioral sensitization in male mice. RNA sequencing and bioinformatics analysis was employed to identify differential expressed (DE) circRNAs, miRNAs, and mRNAs in the nucleus accumbens (NAc) of mice, and the interaction among them was predicted using competing endogenous RNAs (ceRNAs) network analysis. Chronic administration of CBD (40 mg/kg) during the METH withdrawal phase alleviated METH (2 mg/kg)-induced CPP reinstatement and behavioral sensitization in mice, as well as mood and cognitive impairments following behavioral sensitization. Furthermore, 42 DEcircRNAs, 11 DEmiRNAs, and 40 DEmRNAs were identified in the NAc of mice. The circMeis2-miR-183-5p-Kcnj5 network in the NAc of mice is involved in the effects of CBD on METH-induced CPP reinstatement and behavioral sensitization. This study constructed the ceRNAs network for the first time, revealing the potential mechanism of CBD in treating METH-induced CPP reinstatement and behavioral sensitization, thus advancing the application of CBD in METH use disorders.

Methamphetamine and the Synthetic Cathinone 3,4-Methylenedioxypyrovalerone (MDPV) Produce Persistent Effects on Prefrontal and Striatal Microglial Morphology and Neuroimmune Signaling Following Repeated Binge-like Intake in Male and Female Rats

Psychostimulants alter cellular morphology and activate neuroimmune signaling in a number of brain regions, yet few prior studies have investigated their persistence beyond acute abstinence or following high levels of voluntary drug intake. In this study, we examined the effects of the repeated binge-like self-administration (96 h/week for 3 weeks) of methamphetamine (METH) and 21 days of abstinence in female and male rats on changes in cell density, morphology, and cytokine levels in two addiction-related brain regions—the prefrontal cortex (PFC) and dorsal striatum (DStr). We also examined the effects of similar patterns of intake of the cocaine-like synthetic cathinone derivative 3,4-methylenedioxypyrovalerone (MDPV) or saline as a control. Robust levels of METH and MDPV intake (~500–1000 infusions per 96 h period) were observed in both sexes. We observed no changes in astrocyte or neuron density in either region, but decreases in dendritic spine densities were observed in PFC pyramidal and DStr medium spiny neurons. The microglial cell density was decreased in the PFC of METH self-administering animals, accompanied by evidence of microglial apoptosis. Changes in microglial morphology (e.g., decreased territorial volume and ramification and increased cell soma volume) were also observed, indicative of an inflammatory-like state. Multiplex analyses of PFC and DStr cytokine content revealed elevated levels of various interleukins and chemokines only in METH self-administering animals, with region- and sex-dependent effects. Our findings suggest that voluntary binge-like METH or MDPV intake induces similar cellular perturbations in the brain, but they are divergent neuroimmune responses that persist beyond the initial abstinence phase.

Nrf2 expression, mitochondrial fission, and neuronal apoptosis in the prefrontal cortex of methamphetamine abusers and rats

Methamphetamine (MA), a representative amphetamine-type stimulant, is one of the most abused drugs worldwide. Studies have shown that MA-induced neurotoxicity is strongly associated with oxidative stress and apoptosis. While nuclear factor E2-related factor 2 (Nrf2), an antioxidant transcription factor, is known to exert neuroprotective effects, its role in MA-induced dopaminergic neuronal apoptosis remains incompletely understood. In the present study, we explored the effects of MA on the expression levels of Nrf2, dynamin-related protein 1 (Drp1), mitofusin 1 (Mfn1), cytochrome c oxidase (Cyt-c), and cysteine aspartate-specific protease 3 (Caspase 3), as well as the correlations between Nrf2 and mitochondrial dynamics and apoptosis. Brain tissue from MA abusers was collected during autopsy procedures. An MA-dependent rat model was also established by intraperitoneal administration of MA (10 mg/kg daily) for 28 consecutive days, followed by conditioned place preference (CPP) testing. Based on immunohistochemical staining and western blot analysis, the protein expression levels of Nrf2 and Mfn1 showed a decreasing trend, while levels of Drp1, Cyt-c, and Caspase 3 showed an increasing trend in the cerebral prefrontal cortex of both MA abusers and MA-dependent rats. Notably, the expression of Nrf2 was positively associated with the expression of Mfn1, but negatively associated with the expression levels of Drp1, Cyt-c, and Caspase 3. These findings suggest that oxidative stress and mitochondrial fission contribute to neuronal apoptosis, with Nrf2 potentially playing a critical role in MA-induced neurotoxicity.

The Effects of Mkpuru Mmiri Consumption on Cognitive Performance and Brain Histology in an Animal Study

Mkpuru mmiri, popularly known as ice or methamphetamine (METH) is one of the illegal substances that young people in Nigeria abuse most frequently. The purpose of the study is to determine how methamphetamine affects the cognitive-motor behavior of Wistar rats. In the study, twenty-five Wistar rats weighing between 117 and 138 grams were split into five groups: group A had only rat feed and water, group B - D received doses of METH ranging from 5 mg/kg to 20 mg/kg, and group E received a dose of 5 mg/kg of diazepam. Neurobehavioral tools such as the navigator maze test, elevated plus maze and beam walk were used to assess the rats’ memory, anxiety-related behavior, balance, motor coordination, and working memory respectively. Two weeks after the injection, samples were taken and examined for oxidative stress markers (Malondialdehyde - MDA) and tissue antioxidant indicators (Superoxide dismutase - SOD, Glutathione - GSH, and Total Antioxidant Capacity - TAC). The data were analyzed using SPSS and post hoc LSD and the significance level was established at p<0.05. The results showed that the test groups' body weight was significantly lower than the control groups' (p<0.05). The test groups' relative brain weights increased significantly (p<0.05) when compared to the control group. The data also showed a significantly (p<0.05), level of antioxidant enzymes (SOD, GSH, and TAC levels) and a significantly (p<0.05) greater level of MDA when compared to the control group. When comparing the test groups' cognitive abilities to the controls, the experimental rats' cognitive powers significantly declined. The study's conclusion demonstrated that chronic consumption of methamphetamine may deteriorate cognitive function.

Transient receptor potential ankyrin 1 channel modulates the abuse-related mechanisms of methamphetamine through interaction with dopamine transporter.

Methamphetamine (METH) use disorder has risen dramatically over the past decade, and there are currently no FDA-approved medications due, in part, to gaps in our understanding of the pharmacological mechanisms related to METH action in the brain. Here, we investigated whether transient receptor potential ankyrin 1 (TRPA1) mediates each of several METH abuse-related behaviours in rodents: self-administration, drug-primed reinstatement, acquisition of conditioned place preference, and hyperlocomotion. Additionally, METH-induced molecular (i.e., neurotransmitter and protein) changes in the brain were compared between wild-type and TRPA1 knock-out mice. Finally, the relationship between TRPA1 and the dopamine transporter was investigated through immunoprecipitation and dopamine reuptake assays. TRPA1 antagonism blunted METH self-administration and drug-primed reinstatement of METH-seeking behaviour. Further, development of METH-induced conditioned place preference and hyperlocomotion were inhibited by TRPA1 antagonist treatment, effects that were not observed in TRPA1 knock-out mice. Similarly, molecular studies revealed METH-induced increases in dopamine levels and expression of dopamine system-related proteins in wild-type, but not in TRPA1 knock-out mice. Furthermore, pharmacological blockade of TRPA1 receptors reduced the interaction between TRPA1 and the dopamine transporter, thereby increasing dopamine reuptake activity by the transporter. This study demonstrates that TRPA1 is involved in the abuse-related behavioural effects of METH, potentially through its modulatory role in METH-induced activation of dopaminergic neurotransmission. Taken together, these data suggest that TRPA1 may be a novel therapeutic target for treating METH use disorder.

Chemical cousins with contrasting behavioural profiles: MDMA users and methamphetamine users differ in social-cognitive functions and aggression

Methamphetamine (METH, “Crystal Meth”) and 3,4-methylenedioxymethamphetamine (MDMA, “Ecstasy”) share structural-chemical similarities but have distinct psychotropic profiles due to specific neurochemical actions. Previous research has suggested that their impact on social cognitive functions and social behaviour may differ significantly, however, direct comparisons of METH and MDMA users regarding social cognition and interaction are lacking. Performances in cognitive and emotional empathy (Multifaceted Empathy Test) and emotion sensitivity (Face Morphing Task), as well as aggressive social behaviour (Competitive Reaction Time Task) were assessed in samples of n = 40 chronic METH users, n = 39 chronic MDMA users and n = 86 stimulant-naïve controls (total N = 165). Self-reports and hair samples were used to obtain subjective and objective estimates of substance use patterns. METH users displayed diminished cognitive and emotional empathy towards positive stimuli, elevated punitive social behaviour regardless of provocation, and self-reported heightened trait anger relative to controls. MDMA users diverged from the control group only by exhibiting a distinct rise in punitive behaviour when faced with provocation. Correlation analyses indicated that both higher hair concentrations of MDMA and METH may be associated with reduced cognitive empathy. Moreover, greater lifetime MDMA use correlated with increased punitive behaviour among MDMA users. Our findings confirm elevated aggression and empathy deficits in chronic METH users, while chronic MDMA users only displayed more impulsive aggression. Dose-response correlations indicate that some of these deficits might be a consequence of use. Specifically, the dopaminergic mechanism of METH might be responsible for social-cognitive deficits.

The 3,4-methylenedioxymethamphetamine enhances early visual processing for salient socio-emotional stimuli.

The 3,4-methylenedioxymethamphetamine (MDMA) has long been used non-medically, and it is currently under investigation for its potential therapeutic benefits. Both uses may be related to its ability to enhance empathy, sociability, emotional processing and its anxiolytic effects. However, the neural mechanisms underlying these effects, and their specificity to MDMA compared to other stimulants, are not yet fully understood. Here, using electroencephalography (EEG), we investigated the effects of MDMA and a prototypic stimulant, methamphetamine (MA), on early visual processing of socio-emotional stimuli in an oddball emotional faces paradigm. Specifically, we examined whether MDMA or MA enhance the processing of facial expressions, compared to placebo, during the early stages of visual perception. MDMA enhanced an event-related component that is sensitive to detecting faces (N170), specifically for happy and angry expressions compared to neutral faces. MA did not affect this measure, and neither drug altered other components of the response to emotional faces. These findings provide novel insights into the neural mechanisms underlying the effects of MDMA on socio-emotional processing and may have implications for the therapeutic use of MDMA in the treatment of social anxiety and other psychiatric disorders.

Neonatal brain inflammation enhances methamphetamine-induced reinstated behavioral sensitization in adult rats analyzed with explainable machine learning

Neonatal brain inflammation produced by intraperitoneal (i.p.) injection of lipopolysaccharide (LPS) results in long-lasting brain dopaminergic injury and motor disturbances in adult rats. The goal of the present work is to investigate the effect of neonatal systemic LPS exposure (1 or 2 mg/kg, i.p. injection in postnatal day 5, P5, male rats)-induced dopaminergic injury to examine methamphetamine (METH)-induced behavioral sensitization as an indicator of drug addiction. On P70, subjects underwent a treatment schedule of 5 once daily subcutaneous (s.c.) administrations of METH (0.5 mg/kg) (P70–P74) to induce behavioral sensitization. Ninety-six hours following the 5th treatment of METH (P78), the rats received one dose of 0.5 mg/kg METH (s.c.) to reintroduce behavioral sensitization. Hyperlocomotion is a critical index caused by drug abuse, and METH administration has been shown to produce remarkable locomotor-enhancing effects. Therefore, a random forest model was used as the detector to extract the feature interaction patterns among the collected high-dimensional locomotor data. Our approaches identified neonatal systemic LPS exposure dose and METH-treated dates as features significantly associated with METH-induced behavioral sensitization, reinstated behavioral sensitization, and perinatal inflammation in this experimental model of drug addiction. Overall, the analysis suggests that the implementation of machine learning strategies is sensitive enough to detect interaction patterns in locomotor activity. Neonatal LPS exposure also enhanced METH-induced reduction of dopamine transporter expression and [3H]dopamine uptake, reduced mitochondrial complex I activity, and elevated interleukin-1β and cyclooxygenase-2 concentrations in the P78 rat striatum. These results indicate that neonatal systemic LPS exposure produces a persistent dopaminergic lesion leading to a long-lasting change in the brain reward system as indicated by the enhanced METH-induced behavioral sensitization and reinstated behavioral sensitization later in life. These findings indicate that early-life brain inflammation may enhance susceptibility to drug addiction development later in life, which provides new insights for developing potential therapeutic treatments for drug addiction.

Dextromethorphan moderates reward deficiency associated with central serotonin transporter availability in 3,4-methylenedioxy-methamphetamine-treated animals.

The neurotoxicity of 3,4-methylenedioxy-methamphetamine (MDMA) to the serotonergic system is well-documented. Dextromethorphan (DM), an antitussive drug, decreased morphine- or methamphetamine (MA)-induced reward in rats and may prevent MDMA-induced serotonergic deficiency in primates, as indicated by increased serotonin transporter (SERT) availability. We aimed to investigate the effects of DM on reward, behavioral sensitization, and neurotoxicity associated with loss of SERT induced by chronic MDMA administration in rats. Conditioned place preference (CPP) and locomotor activity tests were used to evaluate drug-induced reward and behavioral sensitization; 4-[18F]-ADAM/animal-PET and immunohistochemistry were used to explore the effects of DM on MDMA-induced loss of SERT. MDMA significantly reduced SERT binding in the rat brain; however, co-administration of DM significantly restored SERT, enhancing the recovery rate at day 14 by an average of ~23% compared to the MDMA group. In confirmation of the PET findings, immunochemistry revealed MDMA reduced SERT immunoactivity in all brain regions, whereas DM markedly increased the serotonergic fiber density after MDMA induction. Behavioral tests and in vivo longitudinal PET imaging demonstrated the CPP indexes and locomotor activities of the reward system correlate negatively with PET 4-[18F]ADAM SERT activity in the reward system. Our findings suggest MDMA induces functional abnormalities in a network of brain regions important to decision-making processes and the motivation circuit. DM may exert neuroprotective effects to reverse MDMA-induced neurotoxicity.

Effects of systemic pretreatment with the NAALADase inhibitor 2-PMPA on oral methamphetamine reinforcement in C57BL/6J mice.

Repeated exposure to methamphetamine (MA) in laboratory rodents induces a sensitization of glutamate release within the corticoaccumbens pathway that drives both the rewarding and reinforcing properties of this highly addictive drug. Such findings argue the potential for pharmaceutical agents inhibiting glutamate release or its postsynaptic actions at glutamate receptors as treatment strategies for MA use disorder. One compound that may accomplish both of these pharmacological actions is the N-acetylated-alpha-linked-acidic dipeptidase (NAALADase) inhibitor 2-(phosphonomethyl)pentanedioic acid (2-PMPA). 2-PMPA elevates brain levels of the endogenous agonist of glutamate mGluR3 autoreceptors, N-acetyl-aspartatylglutamate (NAAG), while potentially acting as an NMDA glutamate receptor antagonist. Of relevance to treating psychomotor stimulant use disorders, 2-PMPA is reported to reduce indices of both cocaine and synthetic cathinone reward, as well as cocaine reinforcement in preclinical rodent studies. Herein, we conducted three experiments to pilot the effects of systemic pretreatment with 2-PMPA (0-100 mg/kg, IP) on oral MA self-administration in C57BL/6J mice. The first experiment employed female mice with a prolonged history of MA exposure, while the mice in the second (females) and third (males and females) experiment were MA-naïve prior to study. In all experiments, mice were trained daily to nose-poke for delivery of unadulterated MA solutions until responding stabilized. Then, mice were pretreated with 2-PMPA prior to operant-conditioning sessions in which nose-poking behavior was reinforced by delivery of 120 mg/L or 200 mg/L MA (respectively, in Experiments 1 and 2/3). Contrary to our expectations, 30 mg/kg 2-PMPA pretreatment altered neither appetitive nor consummatory measures related to MA self-administration. In Experiment 3, 100 mg/kg 2-PMPA reduced responding in the MA-reinforced hole, as well as the number of reinforcers earned, but did not significantly lower drug intake. These results provide mixed evidenced related to the efficacy of this NAALADase inhibitor for reducing oral MA reinforcement in female mice.

Methamphetamine intoxication and suicidal ideation/behavior in the emergency department

Background This study investigates the association between Methamphetamine (MA) intoxication and suicidal ideation/behavior in patients presenting to emergency departments. Amidst rising MA use and co-use with opioids, this "twin epidemic" has manifested in increasing admissions for MA intoxication, often accompanied by psychiatric symptoms that can escalate to suicidal behaviors. Method This retrospective study utilized patient records and analyzed data from 629 patients admitted to a Texas emergency department in 2020, with MA intoxication confirmed via urine tests and patient interviews. The suicidal tendencies were assessed using the Columbia-Suicide Severity Scale. The 629 patients were divided into three groups for analysis: Group I (n = 188), MA positive with suicidal ideation (SI) (MA + SI+); Group II (n = 202), MA-positive without SI (MA + SI–); and Group III (n = 239), MA-negative with SI (MA– SI+). Multiple regression analysis was used to elicit clinical features predicting patients presenting to the emergency department with acute MA intoxication. Results Results reveal that approximately half of patients with acute MA intoxication reported suicidal thoughts, indicating a significant association between MA use and suicidal tendencies. Females exhibited higher rates of suicidal thoughts, behavior, and subsequent medical attention compared to males. Sociodemographic characteristics and clinical features differed among MA-positive patients with and without SI. Multivariable regression analysis identified factors influencing MA use, including cannabis use, male gender, agitation, and an inverse association with alcohol use. Notably, the severity and potential lethality of suicidal behavior in MA-intoxicated patients paralleled those observed in psychiatric patients without MA use. Conclusion These results underscore the urgent need for targeted interventions to address the complex interplay between MA use and suicidal risks in the emergency department setting, as well as broader public health strategies to combat the increasing prevalence of MA use.

Hereditary and cortical morphological biomarker of sensitivity to reward in short-term withdrawal methamphetamine abusers.

Higher sensitivity to reward (SR) and weaker sensitivity to punishment (SP) construct the fundamental craving characteristics of methamphetamine abuse. However, few studies have appraised relationships between SR/SP (SR or SP) and cortical morphological alterations in methamphetamine abusers and whether hereditary factors take effects on SR/SP is unclear. Based on surface-based morphometric analysis, cortical discrepancy was investigated between 38 methamphetamine abusers and 37 healthy controls. Within methamphetamine abusers, correlation profiling was performed to discover associations among aberrant neuroimaging substrates, SR, SP, and craving. According to nine single nucleotide polymorphism sites of dopamine-related genes, we conducted univariate general linear model to find different effects of genotypes on cortical alterations and SR/SP/craving (SR, SP, or craving). Ultimately, mediation analyses were conducted among single nucleotide polymorphism sites, SR/SP/craving, and cortical morphological alterations to discover their association pathways. Compared to healthy controls, thinner cortices in inferior temporal gyrus, lateral orbitofrontal cortex, medial orbitofrontal cortex, inferior parietal lobule, and lateral occipital cortex in the left hemisphere were found in methamphetamine abusers (P < 0.05, family-wise error corrected). Cortical thickness in the inferior temporal gyrus was negatively correlated with SR scores. We found that rs1800497 A-containing genotypes had lower cortical thickness in the left inferior parietal lobule than the GG genotype. The rs5751876 had effects on SR scores. This study would provide convincing biomarkers for SR in methamphetamine abusers and offer potential genetic targets for personalizing relapse prevention.

Chronic Administration of Methamphetamine Aggravates Atherosclerotic Vulnerable Plaques in Apolipoprotein E Knockout Mice Fed with a High-cholesterol Diet.

It has been observed previously that chronic methamphetamine (METH) administration could upregulate neuropeptide Y (NPY) expression and promote atherosclerotic formation in apolipoprotein E knockout (ApoE-/-) mice fed with a normal cholesterol or high diet and NPY might be involved in the pathogenesis of METH-induced atherogenic effects through NPY Y1 receptor pathway. Vulnerable coronary atherosclerotic plaque (VP) is a critical pathological finding responsible for the acute coronary syndrome (ACS). In this study, we explored whether METH abuse could aggravate the formation of VP in ApoE-/- mice fed with high cholesterol diet. The purpose of this study was to observe if chronic METH administration could aggravate vulnerable plaque (VP) formation in ApoE-/- mice fed with a high-cholesterol diet. Male ApoE-/- mice fed with a high-cholesterol diet were intraperitoneally injected with normal saline (NS) or 8 mg/kg/day METH (M8) for 24 weeks. Body weight was monitored from baseline to 24 weeks at 2 weeks intervals. After 24 weeks of treatment, plasma lipid variables were measured. Movat's staining and immunohistochemical staining were performed on frozen sections of the aortic roots to calculate VP percentage and intraplaque hemorrhage (IPH) percentage and detect expression of NPY, vascular endothelial growth factor (VEGF), and CD31. In vitro, the expressions of Y2R, VEGF, and CD31 were detected by immunofluorescence staining in aortic endothelial cells incubated with PBS, 100μM METH, 10nmol NPY, or 100μM METH plus 10nmol NPY for 12 hours. The CD31 positive area, percentage of IPH, VP, and the expressions of NPY and VEGF were significantly increased in the M8 group than in the NS group. In vitro, the expressions of Y2R, VEGF, and CD31 were significantly increased in the METH+NPY group than in the PBS, METH, and NPY groups and these effects could be blunted by treatment with a Y2R antagonist or DPPIV inhibitor. Chronic METH administration could aggravate VP in ApoE-/- mice fed with a high-cholesterol diet, possibly through upregulating vascular NPY and VEGF expression and promoting angiogenesis and vessel rupture in atherosclerotic plaques. Our findings indicated that increased VP formation might contribute to the development of acute coronary syndrome post-chronic METH abuse by activating DPPIV/NPY/Y2R pathway.

Combining brief recall and ketamine treatment prevents stress-primed methamphetamine memory reinstatement via heightening mPFC GABA activity

This study aimed to assess whether brief recall of methamphetamine (MA) memory, when combined with ketamine (KE) treatment, may prevent stress-primed MA memory reinstatement. Combining 3-min recall and KE facilitated MA memory extinction and resistance to subsequent stress-primed reinstatement. Such combination also produced glutamate metabotropic receptor 5 (mGluR5) upregulation in animals’ medial prefrontal cortex (mPFC) γ-amino-butyric acid (GABA) neuron. Accordingly, chemogenetic methods were employed to bi-directionally modulate mPFC GABA activity. Following brief recall and KE-produced MA memory extinction, intra-mPFC mDlx-Gi-coupled-human-muscarinic-receptor 4 (hM4Di)-infused mice receiving compound 21 (C21) treatment showed eminent stress-primed reinstatement, while their GABA mGluR5 expression seemed to be unaltered. Intra-mPFC mDlx-Gq-coupled-human-muscarinic-receptor 3 (hM3Dq)-infused mice undergoing C21 treatment displayed MA memory extinction and resistance to stress-provoked reinstatement. These results suggest that combining a brief recall and KE treatment and exciting mPFC GABA neuron may facilitate MA memory extinction and resistance to stress-primed recall. mPFC GABA neuronal activity plays a role in mediating brief recall/KE-produced effects on curbing the stress-provoked MA seeking.

Iraq's Meth Crisis: Prioritizing Research to Combat Suicidal Ideation

As dedicated readers of Al-Kindy College Medical Journal, we are writing to highlight a critical and profoundly concerning matter that requires urgent research attention: the alarming surge in suicidal ideation among users of Iraqi crystal methamphetamine. Expert psychiatrists at Baghdad Medical City and Ibn-Rushd Psychiatry Teaching Hospital have observed this worrisome trend. In tandem, previous studies regarding suicidal ideation among Iraqi medical students have revealed an unexpectedly high prevalence (64.9%). The escalating global trend in amphetamine-type stimulant (ATS) abuse and the distinct challenges posed by crystal meth addiction necessitate comprehensive investigation into the resultant psychological toll.According to the World Drug Report 2022, amphetamines' popularity and use, including methamphetamine, have surged globally, ranking as the second most commonly abused illicit substance after cannabis. This rise in ATS abuse has not spared Iraq, where illicit methamphetamine and captagon use have dramatically increased, notably in Al-Basrah governorate. The transition from opioid-related overdose deaths to the abuse of stimulants like methamphetamine signifies the urgency for novel strategies to monitor and combat this growing public health concern. As methamphetamine misuse becomes more prevalent, it is imperative to prioritize research that explores the mental health consequences of its abuse.

Efficacy of Interpersonal and Social Rhythm Therapy (IPSRT) on Emotion Regulation, Addiction Severity, and Craving in Methamphetamine Abusers

Background: Emotion dysregulation and cravings play a pivotal role in the relapse of individuals grappling with substance use disorders. Objectives: This study aimed to assess the efficacy of Interpersonal and Social Rhythm Therapy (IPSRT) in ameliorating emotion regulation deficits and cravings among methamphetamine abusers in Tehran city. Methods: The study employed a semi-experimental design, featuring both a control group and intervention group. A sample was selected using convenience sampling, and 40 methamphetamine abusers in Tehran city were selected and randomly allocated into two groups: The intervention group (n = 20) and the control group (n = 20). The assessment tools employed included the Difficulties in Emotion Regulation Scale (DERS), the Desires for Drug Questionnaire (DDQ), and the Severity of Dependence Scale (SDS). Data analysis was conducted through mixed repeated ANOVA, independent t-tests, and chi-square tests. Participants were evaluated at pre, post-intervention, and follow-up. Results: The results demonstrate that IPSRT significantly improves emotion regulation and substantially reduces cravings. This was conclusively indicated by the achievement of statistical significance (P &lt; 0.05). The effects of IPSRT were not only immediate but also enduring, as evidenced by consistent positive outcomes observed during the follow-up period. Conclusions: This investigation demonstrated the significant advantages of IPSRT in enhancing emotion regulation, reducing the severity of drug dependence, and craving tendencies among methamphetamine abusers. The findings of this study offer promising implications for the treatment of substance use disorders, reinforcing the potential adoption of IPSRT as a fundamental therapeutic strategy.

Assessment of serum creatinine, urea, and aminotransferase levels among methamphetamine addicted individuals in Khartoum State

Introduction and aim. Methamphetamine-use disorder is a pressing global public health issue. In Sudan, the escalating meth amphetamine (METH) consumption has become a significant social and health problem. This study aims to evaluate liver and kidney biomarkers in methamphetamine addicts in Khartoum state Material and methods. The study was an analytical prospective cross-sectional hospital-based study. One hundred partici pants were enrolled in this study, fifty were cases (methamphetamine addicts), and others were healthy non-METH users as a comparative group. Results. METH users had a mean age of (27±7) years and had been using METH for an average of (14±9) months. Urea and cre atinine levels were also significantly elevated in METH users compared to non-users, with p&lt;0.001 and p=0.044, respectively. Their aspartate transaminase (AST) and alanine transaminase (ALT) levels were significantly higher compared to non-users, with p&lt;0.001. Conclusion. There was significant increases in creatinine, urea, and aminotransferases levels in the case group. ALT showed a moderate positive correlation with abuse duration, while AST showed no significant correlation. Urea and creatinine levels had strong and moderate positive correlations with abuse duration, respectively.

Timing of methamphetamine exposure during adolescence differentially influences parvalbumin and perineuronal net immunoreactivity in the medial prefrontal cortex of female, but not male, rats.

Adolescence involves significant reorganization within the medial prefrontal cortex (mPFC), including modifications to inhibitory neurotransmission that may be mediated through parvalbumin (PV) interneurons and their surrounding perineuronal nets (PNNs). These developmental changes, which can result in increased PV neuron activity in adulthood, may be disrupted by drug use resulting in lasting changes in mPFC function and behavior. Methamphetamine (METH), which is a readily available drug used by some adolescents, increases PV neuron activity and could influence the activity-dependent maturational process of these neurons. In the present study, we used male and female Sprague Dawley rats to test the hypothesis that METH exposure influences PV and PNN expression in a sex- and age-specific manner. Rats were injected daily with saline or 3.0 mg/kg METH from early adolescence (EA; 30-38 days old), late adolescence (LA; 40-48 days old), or young adulthood (60-68 days old). One day following exposure, effects of METH on PV cell and PNN expression were assessed using immunofluorescent labeling within the mPFC. METH exposure did not alter male PV neurons or PNNs. Females exposed in early adolescence or adulthood had more PV expressing neurons while those exposed in later adolescence had fewer, suggesting distinct windows of vulnerability to changes induced by METH exposure. In addition, females exposed to METH had more PNNs and more intense PV neuron staining, further suggesting that METH exposure in adolescence uniquely influences development of inhibitory circuits in the female mPFC. This study indicates that the timing of METH exposure, even within adolescence, influences its neural effects in females.

Childhood Sexual Abuse Moderates the Long-Term Effect of an HIV Prevention Intervention Among Men Who Have Sex With Men With Crystal Methamphetamine Use Disorder

Men who have sex with men (MSM) with a history of childhood sexual abuse (CSA) are more likely to report crystal methamphetamine use and condomless anal intercourse (CAI) than MSM without CSA. MSM with CSA may benefit less in HIV prevention interventions due to long-term psychological effects. Data are from a pilot randomized, controlled trial testing an integrated HIV risk reduction and behavioral activation counseling intervention vs standard of care among MSM with methamphetamine use disorder, which showed effects at reducing CAI. We conducted a secondary analysis (N= 38) to preliminarily assess whether CSA moderated the intervention effects on the two primary outcomes: CAI acts with men whose HIV serostatus was either positive or unknown (1) overall (CAI overall) and (2) while under the influence of methamphetamine (CAI with methamphetamine). At the immediate postintervention assessment, the interaction term between CSA and intervention arm was not statistically significant for either outcome, indicating no moderation effect. However, at the 3-month postintervention assessment, the interaction term was significant for both outcomes. At this time point, for those without CSA, there was a significantly lower number of CAI acts in the intervention condition vs the comparison condition for both outcomes. For those with CSA, however, there was no significant difference between the intervention and comparison conditions for CAI overall, although for the outcome CAI with methamphetamine, the intervention condition had higher levels. Future HIV prevention interventions among MSM with methamphetamine use disorder should consider screening for CSA and addressing CSA-related psychological distress, which may potentially preserve intervention effects.