Methamphetamine and amphetamine pharmacokinetics in oral fluid and plasma after controlled oral methamphetamine administration to human volunteers

Effects of congeners of amphetamine on the human heart

Central stimulatory and hallucinogenic drugs of abuse like amphetamine and most congeners of amphetamine can have cardiac harmful effects. These cardiac side effects can lead to morbidities and death. In this paper, we review current knowledge on the direct and indirect effects of these amphetamine congeners on the mammalian heart-more specifically, the isolated human heart muscle preparation. In detail, we address the question of whether and how these drugs affect cardiac contractility and their mechanisms of action. Based on this information, further research areas are defined, and further research efforts are proposed.

Dog and cat exposures to drugs of abuse identified by the California animal health and food safety laboratory system 2013-2023

Introduction

While known animal exposures to human "drugs of abuse" (DA) were previously considered relatively uncommon in veterinary medicine, the trends are changing. Marijuana and amphetamines are among the 20 toxicants most frequently consulted about with the Pet Poison Helpline. When such exposures occur, they are typically considered emergencies.

Methods

This retrospective study describes confirmed cases of DA exposure in pets from the California Animal Health and Food Safety Laboratory System (CAHFS), 2013-2023.

Results

Fifty-seven samples tested positive for DA through liquid chromatography with tandem mass spectrometry analysis (qualitative method). In 75% (43/57) of the DA screen tests, the detected drugs included amphetamine-type stimulants and metabolites (methamphetamine, amphetamine, or both). In 47% (27/57) of cases, a combination of more than one drug group was found. Most cases were diagnosed from a urine specimen. In at least 32% (18/57) of cases, the samples were submitted due to suspicions of animal cruelty, and at least 41% (23/57) of the patients were deceased when the samples were submitted.

Discussion

More studies on the prevalence of illicit drugs in small animals, using confirmatory testing, are warranted to fully understand the significance of this emerging toxicological hazard in veterinary medicine.

Efficacy of On-line Hemodiafiltration for Rhabdomyolysis Presenting with Acute Kidney Injury Due to Unexpected Drug Abuse

Myoglobin is a well-known cause of acute kidney injury (AKI) due to rhabdomyolysis. However, whether or not removing serum myoglobin by on-line hemodiafiltration (OHDF) improves the kidney function remains unclear. We herein report a patient with a history of methamphetamine abuse who developed AKI due to rhabdomyolysis. A urinalysis and blood collection results obtained before and after OHDF demonstrated that OHDF improved the kidney function by removing a large amount of serum myoglobin rather than via urinary excretion. In conclusion, OHDF may prevent AKI progression effectively when the urine volume is insufficient.

Methamphetamine increases force of contraction in isolated human atrial preparations through the release of noradrenaline

We measured the cardiac contractile effects of the sympathomimetic amphetamine-like drug methamphetamine alone and in the presence of cocaine or propranolol in human atrial preparations. For a more comprehensive analysis, we also examined the effects of methamphetamine in preparations from the left and right atria of mice and, for comparison, analyzed the cardiac effects of amphetamine itself. In human atrial preparations, methamphetamine and amphetamine increased the contractile force, the relaxation rate, and the rate of tension development, and shortened the time to maximum tension and the time to relaxation. Likewise, in mice preparations, methamphetamine and amphetamine increased the contractile force in the left atrium and increased the beating rate in the right atrium. The effect in human atrial preparations started at 1µM, therefore methamphetamine was less effective and potent than isoproterenol in increasing contractile force. These positive inotropic effects of methamphetamine were greatly attenuated by 10µM cocaine and abolished by 10µM propranolol. The inotropic effects of methamphetamine in human atrial preparations were associated with, and are believed to be mediated at least in part by, an increase in the phosphorylation state of the inhibitory subunit of troponin. In conclusion, the sympathomimetic central stimulant drug methamphetamine (as well as amphetamine) increased contractile force and protein phosphorylation, presumably through a release of noradrenaline in isolated human atrial preparations. Thus, methamphetamine acts as an indirect sympathomimetic in the human atrium.

Development of paper-immobilized molecularly imprinted polymers by laser pointer activation for methamphetamine extraction with analysis by ion mobility spectrometry

A fast, simple, cheap, and versatile strategy has been proposed for the synthesis of paper-immobilized molecularly imprinted polymers (MIPs) by photoactivated bulk polymerization over a piece of nitrocellulose using a 405 nm laser pointer. Polymerization was carried out using a mixture of methacrylic acid and ethylene glycol dimethacrylate, using methamphetamine as template molecule and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide as radical initiator. After investigation of different polymerization parameters, the following experimental conditions were found to give best results: size of nitrocellulose strip (13.5 × 4.0 × 0.8 mm), type of porogen (acetonitrile), polymerization mixture volume (75 µL), and irradiation times (10 min). Experimental conditions (such as sample pH, extraction and desorption time, and type and volume of desorption solvent) were also adjusted for the extraction of methamphetamine using the proposed paper-MIP. Methamphetamine determination was carried out by ion mobility spectrometry providing a limit of detection of 14 µg L^-1 and quantitative recoveries from 81 to 95% using spiked urine and oral fluid samples. The proposed paper-immobilized MIP device allows a simple and selective sample extraction procedure for the determination of methamphetamine in oral fluids and urine with a high portability, minimal solvent consumption, and reduced costs compared to other conventional approaches.

Analysis of 2,5-dimethoxy-amphetamines and 2,5-dimethoxy-phenethylamines aiming their determination in biological matrices: a review

PURPOSE

The present review aims to provide an overview of methods for the quantification of 2,5-dimethoxy-amphetamines and -phenethylamines in different biological matrices, both traditional and alternative ones.

METHODS

A complete literature search was carried out with PubMed, Scopus and the World Wide Web using relevant keywords, e.g., designer drugs, amphetamines, phenethylamines, and biological matrices.

RESULTS

Synthetic phenethylamines represent one of the largest classes of "designer drugs", obtained through chemical structure modifications of psychoactive substances to increase their pharmacological activities. This practice is also favored by the fact that every new synthetic compound is not considered illegal by existing legislation. Generally, in a toxicological laboratory, the first monitoring of drugs of abuse is made by rapid screening tests that sometimes can occur in false positive or false negative results. To reduce evaluation errors, it is mandatory to submit the positive samples to confirmatory methods, such as gas chromatography or liquid chromatography combined to mass spectrometry, for a more specific qualitative and quantitative analysis.

CONCLUSIONS

This review highlights the great need for updated comprehensive analytical methods, particularly when analyzing biological matrices, both traditional and alternative ones, for the search of newly emerging designer drugs.

Effects of 3,4-methylenedioxymethamphetamine and methamphetamine on motor vehicle driving performance: A systematic review of experimental and observational studies

Methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA) are common drugs of abuse and driving under their influence may occur in 1 million people yearly in the United States. This systematic review fills the currently unmet need in understanding the effects of METH and MDMA on motor vehicle driving performance (MVP) and provides insight into the forensic community. A PubMed search on September 24, 2020, for experimental and observational studies, which evaluated the impact of METH and MDMA on MVP was performed. After a review of 208 abstracts, 103 were considered potentially interesting and full texts were obtained. After the exclusion of non-English articles, review articles, single case reports, and articles which did not evaluate METH or MDMA on MVP, a total of nine experimental studies, 10 traditional observational studies, and 35 case series were included. The clinical rigor of experimental studies was evaluated using the Jadad scale. Experimental studies often demonstrated no significant MVP safety signals for METH or MDMA use, which was contrary to the overwhelming MVP safety risks found in observational studies. Common driving behaviors while using METH or MDMA include: errors in judgment, traveling at high speeds, failure to stop, merging inappropriately, lane weaving, and crashes. Limitations of experimental studies that led to dissimilar MVP outcomes from observational studies include: the common use of driving simulators, as opposed to actual driving examinations, and doses of METH or MDMA administered may not be representative of blood concentrations seen in observational studies. This systematic review has no funding source and was not registered.

Suitability of SoToxa® Oral Fluid Screening Over Time: Re-examination of Drugged Driving in Wisconsin

Drug impaired driver detection is a critical element of traffic safety. However, shifting drug use patterns over time and geography may limit long-term reliability of assay-based screening tools. In this work, we compare qualitative results from the Abbott SoToxa® oral fluid (OF) screening device to Quantisal™ OF and whole blood. Our objective was to examine these three qualitative toxicological approaches, scope applicability of OF collection at the roadside, and compare to a previous analysis of SoToxa® in Wisconsin. OF specimens were screened with the SoToxa® for six drugs or drug classes including amphetamine, benzodiazepines, cocaine, methamphetamine, opioids, and tetrahydrocannabinol (THC). OF and blood specimens were collected from 106 participants. Quantisal™ OF and blood specimens were screened for drugs on ultra-performance liquid chromatography coupled to quadrupole time-of-flight high-resolution mass spectrometry (UPLC-QToF-HRMS) using a data independent acquisition mode. UPLC-QToF-HRMS data was compared to comprehensive spectral libraries and drugs were qualitatively identified. Drug Recognition Expert evaluations were performed, and face sheets submitted for 21 participants in this work. In general, the SoToxa® results were consistent with the combined qualitative results observed in Quantisal™ OF specimens and whole blood specimens. Limitations were uncovered for benzodiazepines, opioids, and THC. The SoToxa® benzodiazepine assay has high cutoff concentrations for diazepam and clonazepam, limiting its sensitivity and positive predictive value when considering these drugs. SoToxa® opioid screening did not detect fentanyl, which is increasingly prevalent among drug users. Finally, ∆9-THC and its major metabolite 11-nor-9-carboxy-∆9-THC are lipophilic, limiting partitioning into oral fluid. Despite these limitations, the SoToxa® instrument may be useful in assisting law enforcement with identifying individuals driving under the influence of drugs and establishing probable cause at roadside for making impaired driving arrests. Furthermore, Quantisal™ OF may be useful as screening specimens due to their ease of collection and results consistent with whole blood.

Effects and associated transcriptomic landscape changes of methamphetamine on immune cells

Background

Methamphetamine (METH) abuse causes serious health problems, including injury to the immune system, leading to increased incidence of infections and even making withdrawal more difficult. Of course, immune cells, an important part of the immune system, are also injured in methamphetamine abuse. However, due to different research models and the lack of bioinformatics, the mechanism of METH injury to immune cells has not been clarified.

Methods

We examined the response of three common immune cell lines, namely Jurkat, NK-92 and THP-1 cell lines, to methamphetamine by cell viability and apoptosis assay in vitro, and examined their response patterns at the mRNA level by RNA-sequencing. Differential expression analysis of two conditions (control and METH treatment) in three types of immune cells was performed using the DESeq2 R package (1.20.0). And some of the differentially expressed genes were verified by qPCR. We performed Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of differentially expressed genes by the clusterProfiler R package (3.14.3). And gene enrichment analysis was also performed using MetaScape (www.metascape.org).

Results

The viability of the three immune cells was differentially affected by methamphetamine, and the rate of NK-cell apoptosis was significantly increased. At the mRNA level, we found disorders of cholesterol metabolism in Jurkat cells, activation of ERK1 and ERK2 cascade in NK-92 cells, and disruption of calcium transport channels in THP-1 cells. In addition, all three cells showed changes in the phospholipid metabolic process.

Conclusions

The results suggest that both innate and adaptive immune cells are affected by METH abuse, and there may be commonalities between different immune cells at the transcriptome level. These results provide new insights into the potential effects by which METH injures the immune cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01295-9.

Methamphetamine Dysregulates Macrophage Functions and Autophagy to Mediate HIV Neuropathogenesis

HIV-neurocognitive impairment (HIV-NCI) can be a debilitating condition for people with HIV (PWH), despite the success of antiretroviral therapy (ART). Substance use disorder is often a comorbidity with HIV infection. The use of methamphetamine (meth) increases systemic inflammation and CNS damage in PWH. Meth may also increase neuropathogenesis through the functional dysregulation of cells that harbor HIV. Perivascular macrophages are long-lived reservoirs for HIV in the CNS. The impaired clearance of extracellular debris and increased release of reactive oxygen species (ROS) by HIV-infected macrophages cause neurotoxicity. Macroautophagy is a vital intracellular pathway that can regulate, in part, these deleterious processes. We found in HIV-infected primary human macrophages that meth inhibits phagocytosis of aggregated amyloid-β, increases total ROS, and dysregulates autophagic processes. Treatment with widely prescribed ART drugs had minimal effects, although there may be an improvement in phagocytosis when co-administered with meth. Pharmacologically inhibited lysosomal degradation, but not induction of autophagy, further increased ROS in response to meth. Using mass spectrometry, we identified the differentially expressed proteins in meth-treated, HIV-infected macrophages that participate in phagocytosis, mitochondrial function, redox metabolism, and autophagy. Significantly altered proteins may be novel targets for interventional strategies that restore functional homeostasis in HIV-infected macrophages to improve neurocognition in people with HIV-NCI using meth.

Evidence for Gender Differences in the Amphetamine/Methamphetamine Ratio in the Hair of Subjects undergoing Fitness-to-Drive Testing

BACKGROUND AND AIMS

Retrospective analysis of hair testing data provides insights in drugs abuse patterns and improves results interpretation. Cases from subjects undergoing driving fitness assessment (2010-2020) were examined to evidence patterns in methamphetamine (MA) abuse.

MATERIALS AND METHODS

All cases with positive MA (≥0.025 ng/mg) were included (n=585). Data available were gender, age, MA and A (amphetamine) in hair (h), hair color/treatment, length of proximal hair. Cases with Ah/MAh≤0.35 (n=469) were arbitrarily selected to remove as many combined A, MA users. ANOVA was performed to detect Ah/MAh predictors.

RESULTS

No predictors affected Ah/MAh. A bimodal frequency distribution was observed. We clustered cases in two groups (1, Ah/MAh 0.025-0.070; 2, Ah/MAh 0.071-0.120) and performed logistic regression. Only gender exhibited significant difference across groups (p=0.0080). Odds ratio for females falling into group 2 was 2.86 times higher (CI97.5 1.34-6.44).

CONCLUSION

Literature data support the hypothesis that the two Ah/MAh groups represent different phenotypes of the CYP2D6-mediated MA N-demethylation. Whether gender plays a role in such difference could not be confirmed. However, these results provide further suggestion of an association of gender and pharmacogenomics with MA disposition, requiring these factors to be considered in future research.

Dried matrix spots: an evolving trend in the toxicological field

Dried matrix spot (DMS) is a sampling technique, primarily used to analyze blood to diagnose metabolic diseases in newborns. As this technique has several advantages, DMS has started to be employed for other purposes using other biological matrices and increasingly in toxicology over the last decade. The aim of this work was to review the analytical methods using DMS which can be applied to drugs of abuse and which have been published since 2010. Three different databases were searched, using dried, spots, and drugs of abuse as the descriptors and using a snowball search. After applying the exclusion criteria, 39 papers remained. The most common publications were related to the use of blood, which corresponded to 77% of the papers, followed by urine and oral fluid, which corresponded to 13 and 10% of the papers, respectively. The selected studies covered different illicit drugs, sample sizes of 5 to 250 µL and spot sizes ranging from 3 to 18 mm in diameter. This review also examined the extraction techniques and the methods employed to analyze various biological matrices and drugs of abuse, mostly by liquid-extraction and liquid chromatography-tandem mass spectrometry. The benefits of DMS include: a simple sample pretreatment, better stability than liquid matrices, a simple extraction procedure, lower costs, and environmental benefits. DMS appears to be a promising technique in the field of toxicology and provides new perspectives for use in forensic laboratories.

A General Picture of Cucurbit[8]uril Host-Guest Binding

Describing, understanding, and designing complex interaction networks within macromolecular systems remain challenging in modern chemical research. Host-guest systems, despite their relative simplicity in both the structural feature and interaction patterns, still pose problems in theoretical modeling. The barrel-shaped supramolecular container cucurbit[8]uril (CB8) shows promising functionalities in various areas, e.g., catalysis and molecular recognition. It can stably coordinate a series of structurally diverse guests with high affinities. In this work, we examine the binding of seven commonly abused drugs to the CB8 host, aiming at providing a general picture of CB8-guest binding. Extensive sampling of the configurational space of these host-guest systems is performed, and the binding pathway and interaction patterns of CB8-guest complexes are investigated. A thorough comparison of widely used fixed-charge models for drug-like molecules is presented. Iterative refitting of the atomic charges suggests significant conformation dependence of charge generation. The initial model generated at the original conformation could be inaccurate for new conformations explored during conformational search, and the newly fitted charge set improves the prediction-experiment correlation significantly. Our investigations of the configurational space of CB8-drug complexes suggest that the host-guest interactions are more complex than expected. Despite the structural simplicities of these molecules, the conformational fluctuations of the host and the guest molecules and orientations of functional groups lead to the existence of an ensemble of binding modes. The insights of the binding thermodynamics, performance of fixed-charge models, and binding patterns of the CB8-guest systems are useful for studying and elucidating the binding mechanism of other host-guest complexes.

Methamphetamine facilitates HIV infection of primary human monocytes through inhibiting cellular viral restriction factors

Background

Methamphetamine (METH), a potent addictive psychostimulant, is highly prevalent in HIV-infected individuals. Clinically, METH use is implicated in alteration of immune system and increase of HIV spread/replication. Therefore, it is of importance to examine whether METH has direct effect on HIV infection of monocytes, the major target and reservoir cells for the virus.

Results

METH-treated monocytes were more susceptible to HIV infection as evidenced by increased levels of viral proteins (p24 and Pr55Gag) and expression of viral GAG gene. In addition, using HIV Bal with luciferase reporter gene (HIV Bal-eLuc), we showed that METH-treated cells expressed higher luciferase activities than untreated monocytes. Mechanistically, METH inhibited the expression of IFN-λ1, IRF7, STAT1, and the antiviral IFN-stimulated genes (ISGs: OAS2, GBP5, ISG56, Viperin and ISG15). In addition, METH down-regulated the expression of the HIV restriction microRNAs (miR-28, miR-29a, miR-125b, miR-146a, miR-155, miR-223, and miR-382).

Conclusions

METH compromises the intracellular anti-HIV immunity and facilitates HIV replication in primary human monocytes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00703-4.

Increasing emergency department attendances in central London with methamphetamine toxicity and associated harms

BACKGROUND

Methamphetamine is a stimulant drug of abuse with increasing prevalence of use worldwide leading to public health concern. While previous research by our group a decade ago found no evidence of increasing harms associated with methamphetamine use in the UK, there are conflicting data on whether or not this is still the case. This paper aims to identify trends in methamphetamine-related harms and characterise the clinical features of ED presentations involving methamphetamine with gamma-hydroxybutyrate/gamma-butyrolactone (GHB/GBL).

METHODS

We retrospectively interrogated a database of all toxicology-related presentations to two central London EDs, extracting data on drugs involved for presentations relating to methamphetamine between 2005 and 2018 to enable analysis of trends. Further clinical data were extracted for presentations between 2014 and 2018 to give a 4-year case series.

RESULTS

A total of 1244 presentations involving the use of methamphetamine were identified. The number of presentations rose from 4 in 2005 (1.9% of all recreational drug presentations) to 294 (16.2%) in 2018. A total of 850 cases were identified for the 2014-2018 case series, 94.9% were male with a median (range) age of 35.1 (16-67) years. The most common clinical features in the methamphetamine presentations were neuropsychiatric: agitation (41.5%), anxiety (35.2%), hallucinations (16.5%) and psychosis (14.8%). GHB/GBL was co-used in 54.2% of presentations and appeared to attenuate the neuropsychiatric features seen. Use of GHB/GBL was associated with a higher Poisoning Severity Score and requirement for level 2/3 (high dependency unit/intensive care unit (ICU)) care.

CONCLUSION

ED attendances in central London relating to methamphetamine use have risen over the last decade. Combining methamphetamine with GHB/GBL is common and is associated with a higher Poisoning Severity Score and need for ICU level care. Further work is required to establish whether further resources need to be directed at this clinical and public health problem.

Relationship Between Amphetamine Concentrations in Saliva and Serum in Children and Adolescents With Attention-Deficit/Hyperactivity Disorder

BACKGROUND

Therapeutic drug monitoring (TDM) is a valid tool for the optimization of psychopharmacotherapy; however, in child and adolescent psychiatry, uncomfortable intravenous sample collection is the main challenge and restricts the use of TDM. Therefore, it is important to evaluate alternate specimens to facilitate TDM. The aim of this study was to evaluate the feasibility of using saliva for the TDM of amphetamine in children and adolescents with attention-deficit/hyperactivity disorder.

METHODS

In this study, 28 patient samples (mean age, 11.3 years; boys, 23; and girls, 5) treated with lisdexamfetamine were included. The active compound amphetamine was extracted and derivatized before quantification by high-performance liquid chromatography with fluorescence detection. Nonparametric Spearman rank correlations were used for correlation analyses; for clinical validation, Bland-Altman analysis was applied.

RESULTS

The median amphetamine concentrations in saliva were 2.7 times higher (range 0.7-23.6) than those in serum (257.8 ng/mL versus 77.2 ng/mL; z = -4.51, P < 0.001). A strong positive linear correlation was observed between saliva and serum concentrations (ρ = 0.628, P < 0.001). The ratio of saliva-to-serum concentration was strongly pH dependent (ρ = -0.712, P < 0.001). Therefore, a transformation formula, factoring in salivary pH, to calculate serum concentrations from the measured saliva concentrations was applied. Theoretical and measured serum amphetamine concentrations were subjected to Bland-Altman analysis. Using an acceptance limit of 20%, only 21% (n = 6) of samples fulfilled this criterion.

CONCLUSIONS

Amphetamine paired saliva-to-serum concentrations were highly variable and strongly affected by salivary pH, indicating that saliva is an inappropriate sampling matrix for TDM of amphetamine. Furthermore, Bland-Altman analysis did not support saliva as a suitable matrix for TDM.

Electrochemiluminescent screening for methamphetamine metabolites

The abuse of methamphetamine (MA) is to date detected and subsequently verified through the monitoring of MA and its metabolites within biological specimens. Current approaches require complex sample purification strategies alongside significant analysis time. Given the high prevalence of MA within the global drug market, there remains a need for rapid, portable and alternative screening approaches appropriate for direct detection within biological matrices for employment across the forensic and clinical environments. This contribution illustrates the use of an electrochemiluminescence (ECL) strategy for the screening of MA, amphetamine (AMP) and para hydroxy-methamphetamine (pOH-MA) for such applications. The sensing system showed ideal analytical performance with linear ranges at forensically relevant concentrations of 0.1 μM to 0.5 mM for MA, 10 μM to 1 mM AMP and 10 μM to 5 mM for pOH-MA, and superb detection limits of 74.6 nM, 6 μM and 82. μM for MA, AMP and pOH-MA respectively. Furthermore, the sensor was successful in the detection of MA, AMP and pOH-AMP within human pooled serum, artificial urine and saliva, without any prior purification strategies. Here a portable ECL sensor is detailed for the successful employment of the direct screening of these amphetamine type substances and their corresponding metabolites at clinically and forensically relevant concentrations within a range of biological matrices. This approach successfully represents a strong proof-of-concept, for a novel, simple and rapid screening method with significant potential for high-throughput screening of biological samples for drug metabolites, widening the avenues where ECL sensors could be employed.

Psychostimulant use disorder emphasizing methamphetamine and the opioid -dopamine connection: Digging out of a hypodopaminergic ditch

BACKGROUND

Approved food and drug administration (FDA) medications to treat Psychostimulant Use Disorder (PUD) are needed. Both acute and chronic neurological deficits related to the neurophysiological effects of these powerfully addictive drugs can cause stroke and alterations in mood and cognition.

OBJECTIVE

This article presents a brief review of the psychiatric and neurobiological sequelae of methamphetamine use disorder, some known neurogenetic associations impacted by psychostimulants, and explores treatment modalities and outcomes.

HYPOTHESIS

The authors propose that gentle D2 receptor stimulation accomplished via some treatment modalities can induce dopamine release, causing alteration of D2-directed mRNA and thus enhanced function of D2 receptors in the human. This proliferation of D2 receptors, in turn, will induce the attenuation of craving behavior, especially in genetically compromised high-risk populations.

DISCUSSION

A better understanding of the involvement of molecular neurogenetic opioid, mesolimbic dopamine, and psychostimulant connections in "wanting" supports this hypothesis. While both scientific and, clinical professionals search for an FDA approved treatment for PUD the induction of dopamine homeostasis, via activation of the brain reward circuitry, offers treatment for underlying neurotransmitter functional deficits, potential prophylaxis, and support for recovery efforts.

CONCLUSION

Dopamine regulation may help people dig out of their hypodopaminergia ditch.

Entrapment of drugs in dental calculus - Detection validation based on test results from post-mortem investigations

For prospective investigation of drugs and metabolites in archaeological and contemporary dental calculus, a sensitive, broadly applicable ultra-high-performance liquid chromatography-tandem mass spectrometry method using pneumatically assisted electrospray ionisation (UHPLC-ESI-MS/MS) was developed. The dental calculus was treated with citric acid and the dissolution extracts were cleaned using weak and strong polymeric cation-exchange sorbents. The method was validated on hydroxyapatite for the analysis of 67 drugs and metabolites. Typically, the lower limits of quantification were in the range of 0.01-0.05ng for the sample mass extracted. The general applicability of the method was tested using dental calculus material sampled from 10 corpses undergoing forensic autopsy. The calculus material was washed several times before dissolution to remove residual substances originating from saliva, gingival crevicular fluid and blood. The wash extracts and the calculus samples (cleaned calculus material) were analysed using the same instrumental conditions. The dry mass of the calculus samples ranged from 1 to 10mg. The total number of drug detections was 131 in the dental calculus samples and 117 in the whole blood samples. From the analyses of the wash extracts and calculus samples, it was proven that drug residues were trapped in the interior of the calculus material. In 82 of the drug detections, the drug concentrations were higher in the dental calculus than in the blood. Among substances detected in the dental calculus but not in the blood were cocaine, heroin, 6-MAM and THCA-A.

Whether drug detection in urine and oral fluid is similar? A systematic review

Urine has been a biological matrix of choice for drug screening, but recent advances in technology and the introduction of commercial oral fluid assays have effectively established oral fluid as a viable alternative matrix. This systematic review aimed to evaluate the sensitivity of oral fluid in detecting some illicit drugs compared to urine, and to compare the initial and final detection times of these drugs in both fluids. The electronic search in MEDLINE, Cochrane Library, Scopus, and Web of Science was carried out covering studies published from January 2003 and June 2019, in order to find all valid studies that detected drugs in oral fluid and urine in the same patient. Studies about illicit drugs, such as tetrahydrocannabinol, cocaine, amphetamines and illicit opioids, with fluids collection at the same day, controlled drug administration during the study, reported administration interval and time of collection were favored. Out of 2598 studies identified by electronic search, 7 studies were selected for qualitative analysis. Five were clinical trials and 2 were crossover trials. In total, 74 patients aged 20-52 years underwent a diagnostic examination (4 studies with tetrahydrocannabinol, 1 with methamphetamine, and 2 with cocaine) after drug administration. Illicit drug detection in oral fluid is similar to urine but oral fluid has a strong potential for the immediate detection of recent marijuana use compared to urine. In relation to cocaine and methamphetamine, the largest drugs detection window is obtained through urine analysis. Oral fluids cannot replace urine for most of the purposes of drug testing.

Investigating the New Zealand policy response to methamphetamine-contaminated houses

The contamination of houses from clandestine methamphetamine manufacture emerged as an issue in New Zealand in the early 2000s. This perspective reviews and discusses the series of policies developed to address methamphetamine contamination in New Zealand houses over a 15-year period, ending with the reversal of the established policy approach in 2018. The policies addressing methamphetamine contamination of New Zealand properties were influenced by a range of sources including overseas scientific guidelines, local scientific reviews, public housing agency policies, and the local methamphetamine testing industry. A post-remediation methamphetamine level of 0.5 μg/100 cm² was initially implemented in 2010, leading to the termination of public housing tenancies, suspensions from the public housing list, and financial charges for decontamination on public housing tenants. Subsequent reviews of the policy led to some increase in the thresholds (up to 1.5-3.8 μg/100 cm² ) and the adoption of less punitive sanction processes. A scientific review in 2018 recommended a substantial threshold increase to 15 μg/100 cm² (a 30-fold increase on the 2010 standard), resulting in HNZ initiating a plan to compensate previously sanctioned tenants. Overreliance on the "precautionary principle"; strict interpretation of scientific guidelines; and the public housing agency's "zero tolerance approach" to drug use, contributed to an overly punitive policy approach to methamphetamine contamination in New Zealand that negatively impacted vulnerable public housing tenants, landlords, and property owners. Investigation into the extent that all possible influences had on the development of the policies, as well as the consequences of their implementation, should be undertaken.

Oral Fluid Drug Testing: Analytical Approaches, Issues and Interpretation of Results

With advances in analytical technology and new research informing result interpretation, oral fluid (OF) testing has gained acceptance over the past decades as an alternative biological matrix for detecting drugs in forensic and clinical settings. OF testing offers simple, rapid, non-invasive, observed specimen collection. This article offers a review of the scientific literature covering analytical methods and interpretation published over the past two decades for amphetamines, cannabis, cocaine, opioids, and benzodiazepines. Several analytical methods have been published for individual drug classes and, increasingly, for multiple drug classes. The method of OF collection can have a significant impact on the resultant drug concentration. Drug concentrations for amphetamines, cannabis, cocaine, opioids, and benzodiazepines are reviewed in the context of the dosing condition and the collection method. Time of last detection is evaluated against several agencies' cutoffs, including the proposed Substance Abuse and Mental Health Services Administration, European Workplace Drug Testing Society and Driving Under the Influence of Drugs, Alcohol and Medicines cutoffs. A significant correlation was frequently observed between matrices (i.e., between OF and plasma or blood concentrations); however, high intra-subject and inter-subject variability precludes prediction of blood concentrations from OF concentrations. This article will assist individuals in understanding the relative merits and limitations of various methods of OF collection, analysis and interpretation.

Simultaneous Determination of Selegiline, Desmethylselegiline, R/S-methamphetamine, and R/S-amphetamine on Dried Urine Spots by LC/MS/MS: Application to a Pharmacokinetic Study in Urine

Objective: Chiral analysis is a crucial method to differentiate selegiline intake from drug abuse. A dried urine spot (DUS) analytical method based on spotting urine samples (10 μL) onto dried spot collection cards, and followed by air-drying and extraction, was developed and validated for the determination of selegiline, desmethylselegiline, R/S-methamphetamine, and R/S-amphetamine. Methods: Methanol (0.5 mL) was found to be the ideal extraction solvent for target extraction from DUSs under orbital-horizontal stirring on a lateral shaker at 1,450 rpm for 30 min. Determinations were performed by direct electrospray ionization tandem mass spectrometry (ESI-MS/MS) under positive electrospray ionization conditions using multiple reaction monitoring mode. The chromatographic system consisted of a ChirobioticTM V2 column (2.1 × 250 mm, 5 μm) and a mobile phase of methanol containing 0.1% (v/v) glacial acetic acid and 0.02% (v/v) ammonium hydroxide. Results and conclusions: The calibration curves were linear from 50 to 5,000 ng/mL, with r > 0.995 for all analytes, imprecisions ≤ 15% and accuracies between -11.4 and 11.7%. Extraction recoveries ranged from 48.6 to 105.4% with coefficients of variation (CV) ≤ 13.7%, and matrix effects ranged from 45.4 to 104.1% with CV ≤ 10.3%. The lower limit of quantification was 50 ng/mL for each analyte. The present method is simple, rapid (accomplished in 12 min), sensitive, and validated by a pharmacokinetic study in human urine collected after a single oral administration of SG.

Methamphetamine binge administration dose-dependently enhanced negative affect and voluntary drug consumption in rats following prolonged withdrawal: role of hippocampal FADD

While prior studies have established various interacting mechanisms and neural consequences (i.e. monoaminergic nerve terminal damage) that might contribute to the adverse effects caused by methamphetamine administration, the precise mechanisms that mediate relapse during withdrawal remain unknown. This study evaluated the long-term consequences of binge methamphetamine administration (three pulses/day, every 3 hours, 4 days, i.p.; dose-response: 2.5, 5 and 7.5 mg/kg) in adult Sprague-Dawley rats at two behavioral levels following 25 days of withdrawal: (1) negative affect (behavioral despair-forced-swim test, and anhedonia-1% sucrose consumption, two-bottle choice test) and (2) voluntary methamphetamine consumption (20 mg/l, two-bottle choice test). Striatal and hippocampal brain samples were dissected to quantify monoamines content by high-performance liquid chromatography and to evaluate neurotoxicity (dopaminergic and serotonergic markers) and neuroplasticity markers [i.e. cell fate regulator (Fas-associated protein with death domain) FADD] by Western blot. The results showed that methamphetamine administration induced dose-dependent negative effects during prolonged withdrawal in adult rats. In particular, rats treated repeatedly with methamphetamine (7.5 mg/kg) showed (1) enhanced negative affect-increased anhedonia associated with behavioral despair, (2) increased voluntary methamphetamine consumption, (3) enhanced neurotoxicity-decreased dopamine and metabolites in striatum and decreased serotonin in hippocampus, (4) altered neuroplasticity markers-decreased FADD protein and increased p-FADD/FADD balance selectively in hippocampus and (5) higher consumption rates of methamphetamine that were associated with lower FADD content in hippocampus. These results confirm that methamphetamine withdrawal dose-dependently induced negative affect and decreased monoamines content, while also increased voluntary methamphetamine consumption and suggested a role for hippocampal FADD neuroplasticity in these drug-withdrawal adaptations.

Quantitative surface-enhanced Raman spectroscopy chemical analysis using citrate as an in situ calibrant

Direct detection, or inferring the presence of illicit substances, is of great forensic and toxicological value. Surface-enhanced Raman spectroscopy (SERS) has been shown capable of detecting such molecules in a quick and sensitive manner. Herein we describe an analysis strategy for quantitation of low concentrations of three analytes (methamphetamine, cocaine, and papaverine) by SERS analysis using the citrate capping agent that initially saturates the silver nanoparticles' surface as an in situ standard. The citrate is subsequently displaced by the analyte to an extent dependent on the analyte's concentration in the analyte solution. A general model for the competitive adsorption of citrate and a target analyte was developed and used to determine the relative concentrations of the two species coexisting on the surface of the silver nanoparticles. To apply this model, classical least squares (CLS) was used to extract the relative SERS contribution of each of the two species in a given SERS spectrum, thereby accurately determining the analyte concentration in the sample solution. This approach, in essence, transforms citrate into a local standard against which the concentration of an analyte can be reliably determined.

Tracking narcotics consumption at a Southwestern U.S. university campus by wastewater-based epidemiology

Wastewater-based epidemiology (WBE) was applied to estimate the consumption of twelve narcotics within a Southwestern U.S. university campus. Seven consecutive 24-hour composite raw wastewater samples (n = 80) were obtained once per month from sampling locations capturing >95% of campus-generated wastewater. Samples were analyzed for indicators of consumption of morphine, codeine, oxycodone, heroin, fentanyl, methadone, buprenorphine, amphetamine, methylphenidate, alprazolam, cocaine, and MDMA using LC-MS/MS. Eleven indicator compounds (oxycodone, codeine, norcodeine, 6-acetylmorphine, EDDP, amphetamine, alprazolam, alpha-hydroxyalprazolam, cocaine, benzoylecgonine, and MDMA) occurred at 100% detection frequency across the study, followed by morphine-3-glucuronide (98%), noroxycodone (95%), methylphenidate (90%), heroin (7%), norfentanyl (7%), and fentanyl (5%). Estimates of average narcotics consumption ranked as follows in units of mg/day/1000 persons: heroin (474 ± 32), cocaine (551 ± 49), amphetamine (256 ± 12), methylphenidate (236 ± 28), methadone (72 ± 8), oxycodone (80 ± 6), alprazolam (60 ± 2), MDMA (88 ± 35), codeine (50 ± 4), and morphine (18 ± 3). This campus-based WBE study yielded baseline data on 12 narcotics for a U.S. campus and demonstrated for the first time the feasibility of detecting the fentanyl metabolite norfentanyl in this setting.

Field Detection of Drugs of Abuse in Oral Fluid Using the Alere™ DDS®2 Mobile Test System with Confirmation by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

The collection and analysis of drugs in oral fluid (OF) at the roadside has become more feasible with the introduction of portable testing devices such as the Alere™ DDS®2 Mobile Test System (DDS®2). The objective of this study was to compare the on-site results for the DDS®2 to laboratory-based confirmatory assays with respect to detection of drugs of abuse in human subjects. As part of a larger Institutional Review Board approved study, two OF samples were collected from each participant at a music festival in Miami, FL, USA. One OF sample was field screened using the DDS®2, and a confirmatory OF sample was collected using the Quantisal™ OF collection device and submitted to the laboratory for testing. In total, 124 subjects participated in this study providing two contemporaneous OF samples. DDS®2 field screening yielded positive results for delta-9-tetrahydrocannabinol (THC) (n = 27), cocaine (n = 12), amphetamine (n = 3), methamphetamine (n = 3) and benzodiazepine (n = 1). No opiate-positive OF samples were detected. For cocaine, amphetamine, methamphetamine and benzodiazepines, the DDS®2 displayed sensitivity, specificity and accuracy of 100%. For THC, the DDS®2 displayed sensitivity of 90%, specificity of 100% and accuracy of 97.5%, when the threshold for confirmation matched that of the manufacturers advertised cut-off. When this confirmatory threshold was lowered to the analytical limit of detection (i.e., 1 ng/mL), apparent device performance for THC was poorer due to additional samples testing positive by confirmatory assay that had tested negative on the DDS®2, demonstrating a need for correlation between manufacturer cut-off and analytical reporting limit. These results from drug-using subjects demonstrate the value of field-based OF testing, and illustrate the significance of selecting an appropriate confirmation cut-off concentration with respect to performance evaluation and detection of drug use.

Comparison of Cocaine/Crack Biomarkers Concentrations in Oral Fluid, Urine and Plasma Simultaneously Collected From Drug Users

The use of oral fluid (OF) as an alternative specimen for drug analysis has become very popular in forensic toxicology. Many clinical studies have evaluated the correlations between concentrations of cocaine and its metabolites in OF and other matrices, but results have shown high variability. In addition, there are no data available regarding the correlations between biomarkers of crack-cocaine use in different matrices. This study evaluated the relationship between concentrations of cocaine/crack-cocaine biomarkers in OF, urine and plasma samples collected from cocaine users. All samples were analyzed for the presence of cocaine (COC), benzoylecgonine (BZE) and anhydroecgonine (AEC) by a validated liquid chromatography-mass spectrometry method. Median COC, BZE and AEC concentrations ranged from 4.20 to 33.26 ng/mL, from 13.03 to 3,615.86 ng/mL and from 7.40 to 1,892.5 ng/mL across matrices, respectively. The relationship between drug concentrations in OF versus plasma (OF/P) and OF versus urine (OF/U) was evaluated by their coefficients of determination (R2). Least-squares regression analyses demonstrated significant correlations between OF/P and OF/U for cocaine and BE (P < 0.05), with R2 = 0.17, 0.07 for cocaine and R2 = 0.73, 0.45 for BE, respectively. The correlation coefficients (r) found for BZE, COC and AEC in OF/P and OF/U were 0.85 and 0.67 (P < 0.05); 0.41 and 0.26 (P < 0.05); and 0.30 and -0.37 (P > 0.05), respectively. Many factors contribute to the variability of drug correlation ratios in studies involving random samples, including uncertainty about the time of last administration and dosage. Overall, we found significant R2 values for COC and BZE in OF/P and OF/U, but not for AEC. Despite the good correlations found in some cases, especially for BZE, the large variation in drug concentrations seen in this work suggests that OF concentrations should not be used to estimate concentrations of COC, BZE or AEC in plasma and/or urine.

Epigenetic Effects Induced by Methamphetamine and Methamphetamine-Dependent Oxidative Stress

Methamphetamine is a widely abused drug, which possesses neurotoxic activity and powerful addictive effects. Understanding methamphetamine toxicity is key beyond the field of drug abuse since it allows getting an insight into the molecular mechanisms which operate in a variety of neuropsychiatric disorders. In fact, key alterations produced by methamphetamine involve dopamine neurotransmission in a way, which is reminiscent of spontaneous neurodegeneration and psychiatric schizophrenia. Thus, understanding the molecular mechanisms operated by methamphetamine represents a wide window to understand both the addicted brain and a variety of neuropsychiatric disorders. This overlapping, which is already present when looking at the molecular and cellular events promoted immediately after methamphetamine intake, becomes impressive when plastic changes induced in the brain of methamphetamine-addicted patients are considered. Thus, the present manuscript is an attempt to encompass all the molecular events starting at the presynaptic dopamine terminals to reach the nucleus of postsynaptic neurons to explain how specific neurotransmitters and signaling cascades produce persistent genetic modifications, which shift neuronal phenotype and induce behavioral alterations. A special emphasis is posed on disclosing those early and delayed molecular events, which translate an altered neurotransmitter function into epigenetic events, which are derived from the translation of postsynaptic noncanonical signaling into altered gene regulation. All epigenetic effects are considered in light of their persistent changes induced in the postsynaptic neurons including sensitization and desensitization, priming, and shift of neuronal phenotype.

Correlation between Blood and Oral Fluid Psychoactive Drug Concentrations and Cognitive Impairment in Driving under the Influence of Drugs

BACKGROUND

The effects of drugs on driving performance should be checked with drug concentration in the brain and at the same time with the evaluation of both the behavioural and neurophysiological effects. The best accessible indicator of this information is the concentration of the drug and/or metabolites in blood and, to a certain extent, oral fluid. We sought to review international studies on correlation between blood and oral fluid drug concentrations, neurological correlates and cognitive impairment in driving under the influence of drugs.

METHODS

Relevant scientific articles were identified from PubMed, Cochrane Central, Scopus, Web of Science, Science Direct, EMBASE up to April 2017.

RESULTS

Up to 2010, no epidemiological studies were available on this matter and International scientists suggested that even minimal amounts of parent drugs in blood and oral fluid could affect driving impairment. More recently, epidemiological data, systematic reviews and meta-analysis on drugged drivers allowed the suggestion of impairment concentration limits for the most common illicit drugs. These values were obtained comparing driving disability induced by psychotropic drugs with that of established blood alcohol limits. Differently from ethyl alcohol where both detection methods and concentration limits have been well established even with inhomogeneity of ranges within different countries, in case of drugs of abuse no official cut-offs have yet been established, nor any standardized analytical protocols.

CONCLUSION

Multiple aspects of driving performance can be differently affected by illicit drugs, and even if for few of them some dose/concentration dependent impairment has been reported, a wider knowledge on concentration/impairment relationship is still missing.

Methamphetamine: Putting the Brakes on Speed

In only recent history, illicit use of methamphetamine, once isolated to urban areas on the West Coast, has spread into rural areas of the Midwest and southern United States. Although past and current methamphetamine legislation has increased penalties for methamphetamine manufacturers and tightened restrictions on sales of known precursors, the problem still persists. In fact, a 2004 survey indicates that an alarming 6.2% of high school seniors have tried methamphetamine. A number of biological, genetic, and environmental factors influence children's and adolescents’ paths to substance abuse. Nurses should recognize the symptoms of methamphetamine abuse, which include agitation; aggressive behavior; rapid mood swings; hypertension; tachycardia; and eventually lesion-marked skin, clinical depression, and paranoid psychosis. Treatment for methamphetamine addiction includes behavioral therapy. Research on pharmacologic therapy is lacking. Educating youth on methamphetamine prevention appears to be the best approach to curb the spreading use of this addictive and deadly drug.

Zopiclone concentrations in oral fluid and blood after, administration of therapeutic doses of zopiclone

PURPOSE

Little is known about the relationship between concentrations in oral fluid (OF) and blood for the widely prescribed hypnotic drug zopiclone. The purpose of this study was to investigate the usefulness of OF zopiclone concentrations to predict blood zopiclone concentrations in order to introduce OF testing as an alternative to more cumbersome blood testing.

METHODS

16 healthy young male volunteers received capsules of either 5 or 10mg zopiclone on two different study days separated by at least one week. Blood and OF were collected simultaneously at baseline and 9 times after intake of zopiclone on each study day. In addition an OF sample was collected 24-81h after intake. Lunch was served between samples taken 2.5 and 3.5h after intake. All samples were analysed for zopiclone, and the cut-off was 10ng/ml in blood and 0.2ng/ml in OF-buffer mixture.

RESULTS

Zopiclone was detected in all OF samples during the study day. After 24-81h, all subjects were also positive for zopiclone in OF, except from three subjects ingesting the 5mg dose. In a single case zopiclone was detected in a baseline OF sample 14days after intake on an earlier study day. Zopiclone was detected in both OF and blood in 231 OF/blood pairs, and a significant but weak correlation between OF and blood concentration was seen (R² of 0.30). The median (range) zopiclone OF/blood concentration ratio (ZOBCR) for all samples were 3.3 (0.8-18). The ZOBCR decreased when the OF volume increased. After 30 of 31 given doses of zopiclone, the ZOBCR was higher in samples collected before lunch than samples collected after lunch.

DISCUSSION

Vast intra- and interindividual differences in ZOBCR were found, and the correlation between OF and blood concentration was less pronounced than reported in former studies. In accordance with earlier studies we found a negative correlation between ZOBCR and OF volume. The ZOBCR decreases in relation to recent intake of a meal, probably because stimulated saliva production causes "dilution" of saliva. OF zopiclone concentration appeared unsuitable for estimation of blood zopiclone concentration. Due to long detection time, analysis of zopiclone in OF might be useful to detect non-recent, previous intake.

Involvement of PUMA in pericyte migration induced by methamphetamine

Mounting evidence indicates that methamphetamine causes blood-brain barrier damage, with emphasis on endothelial cells. The role of pericytes in methamphetamine-induced BBB damage remains unknown. Our study demonstrated that methamphetamine increased the migration of pericytes from the endothelial basement membrane. However, the detailed mechanisms underlying this process remain poorly understood. Thus, we examined the molecular mechanisms involved in methamphetamine-induced pericyte migration. The results showed that exposure of C3H/10T1/2 cells and HBVPs to methamphetamine increased PUMA expression via activation of the sigma-1 receptor, MAPK and Akt/PI3K pathways. Moreover, methamphetamine treatment resulted in the increased migration of C3H/10T1/2 cells and HBVPs. Knockdown of PUMA in pericytes transduced with PUMA siRNA attenuated the methamphetamine-induced increase in cell migration through attenuation of integrin and tyrosine kinase mechanisms, implicating a role of PUMA in the migration of C3H/10T1/2 cells and HBVPs. This study has demonstrated that methamphetamine-mediated pericytes migration involves PUMA up-regulation. Thus, targeted studies of PUMA could provide insights to facilitate the development of a potential therapeutic approach for alleviation of methamphetamine-induced pericyte migration.

Methylphenidate for Treating ADHD: A Naturalistic Clinical Study of Methylphenidate Blood Concentrations in Children and Adults With Optimized Dosage

Background

Methylphenidate (MPH), along with behavioral and psychosocial interventions, is the first-line medication to treat attention-deficit hyperactivity disorder (ADHD) in Sweden. The dose of MPH for good symptom control differs between patients. However, studies of MPH concentration measurement in ADHD treatment are limited.

Objective

To describe blood and oral fluid (OF) concentrations of MPH after administration of medication in patients with well-adjusted MPH treatment for ADHD, and to identify the most suitable matrix for accurate MPH concentration during treatment.

Methods

Patients were recruited from Child and Adolescent Psychiatry (CAP), General Psychiatry (GP), and the Department of Dependency (DD). Blood and OF samples were collected in the morning before MPH administration as well as 1 and 6 h after administration of the prescribed morning dose of MPH.

Results

Fifty-nine patients aged between 9 and 69 years, 76 % males. The daily dose of MPH varied from 18 to 180 mg, but the median daily dose per body weight was similar, approximately 1.0 mg/kg body weight. The median MPH concentration in blood 1 and 6 h after the morning dose was 5.4 and 9.3 ng/mL, respectively. Highly variable OF-to-blood ratios for MPH were found at all time points for all three groups.

Conclusions

Weight is a reliable clinical parameter for optimal dose titration. Otherwise, MPH blood concentration might be used for individual dose optimization and for monitoring of the prescribed dose. Relying only on the outcome in OF cannot be recommended for evaluation of accurate MPH concentrations for treatment monitoring.

Silencing microRNA-143 protects the integrity of the blood-brain barrier: implications for methamphetamine abuse

MicroRNA-143 (miR-143) plays a critical role in various cellular processes; however, the role of miR-143 in the maintenance of blood-brain barrier (BBB) integrity remains poorly defined. Silencing miR-143 in a genetic animal model or via an anti-miR-143 lentivirus prevented the BBB damage induced by methamphetamine. miR-143, which targets p53 unregulated modulator of apoptosis (PUMA), increased the permeability of human brain endothelial cells and concomitantly decreased the expression of tight junction proteins (TJPs). Silencing miR-143 increased the expression of TJPs and protected the BBB integrity against the effects of methamphetamine treatment. PUMA overexpression increased the TJP expression through a mechanism that involved the NF-κB and p53 transcription factor pathways. Mechanistically, methamphetamine mediated up-regulation of miR-143 via sigma-1 receptor with sequential activation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3' kinase (PI3K)/Akt and STAT3 pathways. These results indicated that silencing miR-143 could provide a novel therapeutic strategy for BBB damage-related vascular dysfunction.

Mir143-BBC3 cascade reduces microglial survival via interplay between apoptosis and autophagy: Implications for methamphetamine-mediated neurotoxicity

BBC3 (BCL2 binding component 3) is a known apoptosis inducer; however, its role in microglial survival remains poorly understood. In addition to the classical transcription factor TRP53, Mir143 is involved in BBC3 expression at the post-transcriptional level. Here, we identify unique roles of Mir143-BBC3 in mediating microglial survival via the regulation of the interplay between apoptosis and autophagy. Autophagy inhibition accelerated methamphetamine-induced apoptosis, whereas autophagy induction attenuated the decrease in microglial survival. Moreover, anti-Mir143-dependent BBC3 upregulation reversed the methamphetamine-induced decrease in microglial survival via the regulation of apoptosis and autophagy. The in vivo relevance of these findings was confirmed in mouse models, which demonstrated that the microinjection of anti-Mir143 into the hippocampus ameliorated the methamphetamine-induced decrease in microglia as well as that observed in heterozygous Mir143(+/-) mice. These findings provide new insight regarding the specific contributions of Mir143-BBC3 to microglial survival in the context of drug abuse.

Exposures associated with clandestine methamphetamine drug laboratories in Australia

The clandestine manufacture of methamphetamine in residential homes may represent significant hazards and exposures not only to those involved in the manufacture of the drugs but also to others living in the home (including children), neighbours and first responders to the premises. These hazards are associated with the nature and improper storage and use of precursor chemicals, intermediate chemicals and wastes, gases and methamphetamine residues generated during manufacture and the drugs themselves. Many of these compounds are persistent and result in exposures inside a home not only during manufacture but after the laboratory has been seized or removed. Hence new occupants of buildings formerly used to manufacture methamphetamine may be unknowingly exposed to these hazards. Children are most susceptible to these hazards and evidence is available in the literature to indicate that these exposures may result in immediate and long-term adverse health effects. The assessment of exposure within the home can be undertaken by measuring contaminant levels or collecting appropriate biological data from individuals exposed. To gain a better understanding of the available data and key issues associated with these approaches to the characterisation of exposure, a review of the published literature has been undertaken.