Synthetic Cannabinoids: A Pharmacological and Toxicological Overview

Identifying EEG markers related to acute cannabis consumption: A systematic review

BACKGROUND/RATIONALE

Electroencephalography (EEG) has potential to provide a sensitive measure of the acute neurophysiological response to cannabis administration. As delta-9-tetrahydrocannabinol (THC; the psychoactive constituent of cannabis) can induce transient neurocognitive impairments that differ as a function of tolerance and dose, understanding the neural profile related to intoxication would be of great benefit in the wake of increasing recreational and medicinal use. Accordingly, the present systematic review examined the current research literature related to acute cannabis administration and EEG measures.

METHODS

Peer-reviewed articles published from 2000 were assessed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that administered non-synthetic cannabis, containing THC (orally or inhaled) and reported differences in EEG outcomes within the acute time frame (<6 hours post-administration) as compared to baseline or placebo, were eligible for inclusion.

RESULTS/DISCUSSION

A total of 16 studies were eligible for inclusion, of which 11 reported differences in the amplitude/latency of event-related potentials (ERPs) and 9 reported changes in frequency band power. Of the ERPs, the P3 was identified as a potential indicator of recent cannabis consumption, as demonstrated by decreased P3 amplitude across various doses (generally exhibiting small-to-moderate magnitude effects where effect sizes were reported). Oscillatory activity in the theta frequency band power range (typically 4-7 Hz) was impacted following cannabis administration, with some support for a dose-dependent change in power. The present results highlight the potential utility of some EEG measures as markers of recent cannabis consumption, although great heterogeneity in participant characteristics and reported data limits conclusions from these results. It is also evident that EEG changes in highly tolerant user groups (such as those who use cannabis medicinally), require further exploration.

Emerging risk factors for heart failure in younger populations: A growing public health concern

Heart failure (HF) is a growing public health concern, with an increasing incidence among younger populations. Traditionally, HF was considered a condition primarily affecting the elderly, but of late, emerging evidence hints at a rapidly rising HF incidence in youth in the past 2 decades. HF in youth has been linked to a complex interaction between emerging risk factors, such as metabolic syndrome, environmental exposures, genetic predispositions, and lifestyle behaviors. This review examines these evolving determinants, including substance abuse, autoimmune diseases, and the long-term cardiovascular effects of coronavirus disease 2019, which disproportionately affect younger individuals. Through a comprehensive analysis, the study highlights the importance of early detection, targeted prevention strategies, and multidisciplinary management approaches to address this alarming trend. Promoting awareness and integrating age-specific interventions could significantly reduce the burden of HF and improve long-term outcomes among younger populations.

Repeated treatment with JWH-018 progressively increases motor activity and aggressiveness in male mice: involvement of CB1 cannabinoid and D1/D2 dopaminergic receptors

RATIONALE

To date, the exposure to Synthetic Cannabinoids (SCs) has been linked to unanticipated psychiatric symptoms such as agitation, psychosis, and aggressive behavior. In line with this, preclinical studies have shown that acute and long-term exposure to these compounds can result in psychostimulant effects that may be related to CB1-mediated and dopamine-dependent mechanisms.

OBJECTIVES

This study focuses on the progressive effects induced by repeated injection of 1-pentyl-3-(1-naphthoyl)indole JWH-018 (6 mg/kg, i.p.) on the locomotor activity and aggressive behavior in adult male ICR-CD1® mice. Thus, the interaction with the cannabinoid CB1 receptor-preferring antagonist/inverse agonist AM-251 (6 mg/kg, i.p.), the dopamine D1/5 receptor antagonist SCH23390 (0.1 mg/kg, i.p.), and the dopamine D2/3 receptor antagonist haloperidol (0.05 mg/kg, i.p.) have been evaluated. Expression and distribution of D1 and D2 receptors and tyrosine hydroxylase (TH) have been also investigated by immunohistochemistry on brain and cerebellar samples to explore potential neuroplastic events.

RESULTS

The repeated treatment with JWH-018 lead to the exacerbation of unanticipated psychomotor agitation, progressively increasing spontaneous locomotion and aggressiveness. Pre-treatment with AM-251 prevents the effects induced by the SC first, third and seventh injection. SCH23390 and haloperidol significantly attenuate and fully prevent the effects induced by JWH-018 seventh injection when pre-administered, respectively, alone and in combination. Behavioral changes observed in JWH-018-treated mice are accompanied by alterations in cortical, hippocampal, striatal and cerebellar D1, D2 and TH gene expression levels.

CONCLUSION

The present results demonstrated that repeated treatment with high dosage of JWH-018 induces psycho-stimulants effects via both CB1 receptor-mediated and dopamine-dependent mechanisms.

Binding Affinity of Synthetic Cannabinoids to Human Serum Albumin: Site Characterization and Interaction Insights

Background/Objectives: High-performance affinity chromatography (HPAC) was used to investigate the binding affinity of a series of synthetic cannabinoids, a widely abused class of new psychoactive substances, to human serum albumin (HSA) and obtain insights into the binding sites. To better understand the recognition mechanisms, molecular docking studies were conducted. Methods: Binding affinity was assessed through zonal elution approach Additionally, displacement chromatography with site-specific probes provided insights into the HSA binding sites of five synthetic cannabinoids. Results: That these drugs exhibit extensive binding to HSA, with values ranging from 98.7% to 99.9%. Competition for site I was observed between warfarin and four synthetic cannabinoids (5F-AMB, AB-PINACA, AMB-FUBINACA, and AB-CHMINACA). Furthermore, AB-CHMINACA also competed with L-tryptophan for site II. The binding affinity of all synthetic cannabinoids increased in the presence of (S)-ibuprofen. Molecular docking studies supported the experimental findings, reinforcing the insights gained. Conclusions: The key novelty of this study lies in analyzing, for the first time, the binding affinity of synthetic cannabinoids to HSA through HPAC and molecular docking. These results may improve our understanding of their toxicokinetic behavior and help in predicting possible competitive interactions that could influence HSA binding and, consequently, their activity and toxicity. This study is the first to describe the binding affinity of synthetic cannabinoids to HSA, elucidate their recognition mechanisms, identify binding sites, and characterize their interactions with the protein.

Acute cannabis intoxication among the paediatric population

This narrative review synthesizes the toxicological, clinical and medico-legal aspects of paediatric cannabis intoxication. By providing a comprehensive overview, it aims to inform future research, guide policymaking, and enhance clinical and toxicological practice in addressing this growing public health concern. The pharmacokinetics of cannabinoid ingestion in children are significantly influenced by the immaturity of their gastrointestinal tract and metabolic enzyme systems, resulting in altered oral bioavailability. Clinical data indicate that Δ9-tetrahydrocannabinol (THC)-related effects in paediatricpaediatric patients typically emerge within 2 hours of ingestion, with more severe symptoms developing within 4 hours. The endocannabinoid system (ECS) undergoes significant developmental changes, with marked differences in cannabinoid receptor expression and distribution across fetal, neonatal, and adult brains. During neurodevelopment, CB1 receptors exhibit unique expression patterns, including transient localization in brainstem regions critical for neurovegetative functions. These developmental dynamics likely explain children's heightened sensitivity to THC's neurological and neurovegetative effects, often resulting in more severe outcomes compared to adults. The reliable detection of cannabinoids involves integrating screening methods with confirmatory analytical techniques. Urine immunoassay testing is widely considered an helpful toolto assess a previous exposure, becoming positive within 3-4 h of ingestion. However, this method is prone to false positives. Plasma THC concentration, when measured close to the event, offers valuable insights into the quantity ingested and the correlation between exposure and clinical outcomes in the impairment window. Hair analysis, while useful for distinguishing between acute and chronic use, is susceptible to various biases. The rising incidence of acute cannabis intoxication in children underscores the urgent need for targeted public health interventions and stricter regulatory frameworks. Preventive measures such as child-resistant packaging, public education campaigns, and cannabis use screening during pregnancy are essential to mitigate risks. Clinicians should consider THC exposure in the differential diagnosis of children presenting with unexplained neurological, immune, or metabolic symptoms.

ADB-FUBINACA-induced developmental toxicity, neurotoxicity, and cardiotoxicity in embryonic zebrafish (Danio rerio)

As an emerging pollutant, the synthetic cannabinoid N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (ADB-FUBINACA) is widely abused and frequently detected in metropolitan wastewater. However, its effect on aquatic organisms remains unexplored. In this study, embryonic and larval zebrafish were exposed to sublethal concentrations of ADB-FUBINACA to assess its toxic effects via behavioral, biochemical, and metabolomic analyses. The observed morphological defects included reduced heartbeat, shorter body length, spinal deformation, and pericardial edema. Transgenic zebrafish exhibited cardiac developmental defects and apoptosis, indicating that cardiotoxicity is associated with dysregulated gene expression. Impaired motor activity and disrupted neuronal development suggested neurotoxicity. Elevated reactive oxygen species (ROS) and malondialdehyde (MDA) levels indicate oxidative stress, whereas transcriptional changes in immune-related genes reflect a dysregulated inflammatory response. Metabolomic analyses revealed disruptions in pathways related to alanine, purine, and pyrimidine metabolism, and arginine biosynthesis, which correlated with oxidative damage, cardiotoxicity, and neurodevelopmental effects. In conclusion, ADB-FUBINACA induces developmental toxicity in zebrafish embryos via oxidative stress and metabolic disruption, highlighting the potential environmental risks posed by this emerging pollutant.

An Outbreak of Synthetic Cannabinoid-Adulterated Tianeptine Products in New Jersey - Case Series

BACKGROUND

Tianeptine, an atypical antidepressant not approved in the United States, is readily purchased from unregulated markets such as the internet and gas stations. We became aware of a cluster of 34 patients in New Jersey who became ill following ingestion of the tianeptine containing-product Neptune's Fix, the rate of which (4.6 cases per month) far exceeded the background rate for this substance of 0.5 cases per year.

METHODS

We retrospectively identified tianeptine exposures reported to the New Jersey Poison Information and Education System (NJPIES) prior to June 2023 to determine the background rate of tianeptine exposure. From June 2023- February 2024 we prospectively surveilled tianeptine exposures reported to NJPIES, recorded demographic and clinical information, and recruited samples for testing. Six samples of the ingested products were obtained and analyzed using gas chromatography mass spectrometry (GC-MS) and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Whole blood samples from two patients were tested for tianeptine and synthetic cannabinoids.

RESULTS

During the period of interest, NJPIES received 41 exposure calls, with 37 reporting acute toxicity in 34 unique patients, two reporting chronic tianeptine use, and two reporting withdrawal. Among the 37 exposures resulting in acute toxicity, commonly reported effects included altered mental status, tachycardia, hypotension, and seizures. 43% (n = 16) were intubated, and 65% (n = 24) were admitted to the ICU. Analytical testing of six samples identified variable product composition, containing various xenobiotics including tianeptine, kava alkaloids, natural cannabinoids, and the synthetic cannabinoids MDMB-4en-PINACA and ADB-4en-PINACA. MDMB-4en-PINACA was detected in one of the two patient blood specimens.

CONCLUSIONS

These cases represent a marked increase in tianeptine exposures compared with the poison center's historical average. Analytical testing revealed variable product composition, including the presence of synthetic cannabinoids. Clinicians should be aware that tianeptine containing products are widely available, unregulated, and can be adulterated.

Long-term consequences of adolescent exposure to the synthetic cannabinoid AB-FUBINACA in male and female mice

The consumption of synthetic cannabinoids during adolescence is reported to be a risk factor for the appearance of psychiatric disorders later in life. AB-FUBINACA is a member of the indazole carboxamide family of synthetic cannabinoids present in Spice/K2 preparations. The present study sought to investigate the long-term effects of AB-FUBINACA consumption during adolescence in both male and female mice. AB-FUBINACA revealed several sex-dependent behavioral alterations. In this sense, the administration of this synthetic cannabinoid in female, but not male, mice induced psychotic-like symptoms which were associated with changes in dendritic arborization and density of mature dendritic spines in pyramidal neurons of the prefrontal cortex, as well as with an up-regulation of differentially expressed genes in this brain area. This study helps to clarify the potential late detrimental effects of this potent synthetic cannabinoid that may derive from its use during adolescence.

International Symposium on Ruminant Physiology: The involvement of the endocannabinoid system in metabolic and inflammatory responses in dairy cows during negative energy balance

The endocannabinoid system (ECS) is involved in the regulation of energy metabolism, immune function and reproduction in mammals. The ECS is consisted of the endocannabinoid (eCB) ligands, enzymes, and cannabinoid receptors. In mammals, the cannabinoid-1 receptor (CB1/CNR1) is expressed in the central nervous system and in peripheral tissues; and its activation increases anabolic processes. The cannabinoid-2 receptor (CB2/CNR2) is most highly expressed in immune cells, and its activation exerts mainly anti-inflammatory effects. Until recently, little was known about the involvement of the ECS in physiological responses in dairy cows. As peripartum dairy cows undergo vast changes in energy metabolism and immune function, processes that are regulated by the ECS, several studies characterized ECS components in transition cows. Concentrations of eCB in the adipose tissue were higher postpartum (PP), and levels of the eCB N-arachidonoylethanolamide (AEA) were increased PP compared with prepartum. Exogenous injections of AEA to transition cows may increase adipose deposition, but did not affect feed intake. In vitro models showed that bovine adipocyte metabolism was differentially affected by CB1 agonists and antagonists in nonlactating non-gestating compared with PP cows. Thus, the responses of the PP dairy cows to ECS modulations may be related to the physiological and reproductive stage of the cow. Currently, whole-body ECS activation via agonists is mostly not feasible in vivo in livestock. Alternatively, downregulation of ECS activation can be achieved by supplementation of omega-3 (n-3) fatty acids. Indeed, in vivo studies with transition cows supplemented with n-3 showed a moderate downregulation of ECS components in the blood, adipose and liver, improved systemic insulin sensitivity, but evidently reduced insulin sensitivity in the adipose tissue PP. The abundance of CB1 was lower in immune cells, and anti-inflammatory effects were found in PP cows supplemented with n-3; possibly associating ECS downregulation with immune function. The physiological impact of ECS activation is an exciting and complex area of research, that could influence the physiology of dairy cows during metabolic and inflammatory challenges. Dairy cows may be an experimental model for ECS modulations, with broader relevance to female mammals. More research is required on how selective ECS activation/downregulation in tissues could affect immune-metabolic function in dairy cows.

Renal Outcomes and Other Adverse Effects of Cannabinoid Supplementation

This narrative review explores the benefits and risks of cannabinoids in kidney health, particularly in individuals with pre-existing renal conditions. It discusses the roles of cannabinoid receptor ligands (phytocannabinoids, synthetic cannabinoids, and endocannabinoids) in kidney physiology. The metabolism and excretion of these substances are also highlighted, with partial elimination occurring via the kidneys. The effects of cannabinoids on kidney function are examined, emphasizing both their potential to offer nephroprotection and the risks they may pose, such as cannabinoid hyperemesis syndrome and ischemia-reperfusion injury. These complexities underscore the intricate interactions between cannabinoids and renal health. Furthermore, this review highlights the association between chronic synthetic cannabinoid use and acute kidney injury, stressing the need for further research into their mechanisms and risks. This article also highlights the growing prevalence of edible cannabis and hemp seed consumption, emphasizing their nutritional benefits, legal regulations, and challenges such as inconsistent labeling, potential health risks, and implications for kidney health. The review delves into the roles of CB1 and CB2 receptors in diabetic nephropathy, chronic kidney disease, and obesity-related kidney dysfunction, discussing the therapeutic potential of CB2 agonists and CB1 antagonists. Additionally, it examines the potential diuretic and anti-inflammatory effects of cannabinoids in preventing kidney stones, suggesting that cannabinoids could reduce crystal retention and lower the risk of stone formation. Cannabinoids' effects on kidneys depend heavily on the characteristics of individual substances, as synthetic cannabinoids pose a major threat to the health of users. Cannabinoids offer therapeutic potential but require more research to confirm their benefits. Distinguishing between therapeutic cannabinoids and harmful synthetic variants is crucial for safe clinical application.

Postmortem findings of organ damage in novel psychoactive substances users: A comprehensive review

INTRODUCTION

Despite the rising number of NPS-related deaths, comprehensive data on their prevalence, identification, and associated organ damage remain scarce.

MATERIALS AND METHODS

A literature search was conducted. Predefined inclusion and exclusion criteria were applied, resulting in the identification of 197 articles.

RESULTS

We identified 446 cases of NPS-related deaths, involving a total of 176 different substances. Synthetic opioids were the most prevalent class (34 %), followed by synthetic cannabinoids (22 %) and cathinones (21 %). Co-ingestion of NPS with other substances occurred in 77 % of cases. Macroscopic findings varied across organs, with congestion and edema most observed in the brain (23 %) and lung (56 %), respectively.

DISCUSSION

The existing literature lacks comprehensive descriptions of organs subjected to autopsy and histological examination in NPS-positive subjects. Despite this limitation, our findings underscore the prominence of lung pathology. Moreover, the prevalence of normal organs in cases of acute intoxication is a significant observation. We advocate for future research to provide more detailed insights to enhance our understanding of the multifaceted landscape of NPS-related deaths.

Synthetic cannabinoid identification in cases associated with blue lotus and valerian root vaping products

Synthetic cannabinoids emerged in the early 21st century and have continued to evolve and flourish to present day. Like other novel psychoactive substances (NPS), synthetic cannabinoids have been sold under the guise of legitimate products. Some examples include "potpourri," "incense," and herbal material. Between May 2020 and December 2023, the United States Army Criminal Investigation Laboratory, Drug Chemistry Division (USACIL) received 29 seized drug cases mentioning "blue lotus" or "valerian root." In 90% of these cases, at least one exhibit contained one or more synthetic cannabinoids. During the same timeframe, the Armed Forces Medical Examiner System, Division of Forensic Toxicology received 65 toxicology cases that contained synthetic cannabinoids and/or their corresponding metabolites where case history mentioned "blue lotus." The most frequently observed synthetic cannabinoids between laboratories were 5F-MDMB-PICA, ADB-BUTINACA, and MDMB-4en-PINACA. Innocuous branding and marketing may deceive law enforcement, investigators, and healthcare providers into believing that the adverse effects of erratic behavior, sedation, slurred speech, and hallucinations are a result of toxicity from botanical extracts (e.g. apomorphine and nuciferine in blue lotus). Due to the dangerous nature of these NPS, synthetic cannabinoid screening is recommended for all cases where there is suspected use of vaping products suggested to contain "blue lotus" or "valerian root" as vendors continue to conceal the presence of these compounds.

Retinoids and retinoid-binding proteins: Unexpected roles in metabolic disease

Alterations in tissue expression levels of both retinol-binding protein 2 (RBP2) and retinol-binding protein 4 (RBP4) have been associated with metabolic disease, specifically with obesity, glucose intolerance and hepatic steatosis. Our laboratories have shown that this involves novel pathways not previously considered as possible linkages between impaired retinoid metabolism and metabolic disease development. We have established both biochemically and structurally that RBP2 binds with very high affinity to very long-chain unsaturated 2-monoacylglycerols like the canonical endocannabinoid 2-arachidonoyl glycerol (2-AG) and other endocannabinoid-like substances. Binding of retinol or 2-MAGs involves the same binding pocket and 2-MAGs are able to displace retinol binding. Consequently, RBP2 is a physiologically relevant binding protein for endocannabinoids and endocannabinoid-like substances and is a nexus where the very potent retinoid and endocannabinoid signaling pathways converge. When Rbp2-null mice are challenged orally with fat, this gives rise to elevated levels in the proximal small intestine of both 2-AG and the incretin hormone glucose-dependent insulinotropic polypeptide (GIP) in the proximal small intestine. We propose that elevation of GIP concentrations upon high fat diet feeding gives rise to obesity and the other elements of metabolic disease seen in Rbp2-null mice. Unexpectedly, we observed that RBP4 is present in secretory granules of the GIP-secreting intestinal K-cells and is co-secreted with GIP in response to a stimulus that provokes GIP secretion. Moreover, RBP4 is co-secreted along with glucagon from pancreatic alpha-cells in response to a secretory stimulus. The association during the secretory process of RBP4 with potent hormones that regulate metabolism (GIP and glucagon) accounts for at least some of the metabolic disease seen upon overexpression of Rbp4.

Feature-Based Molecular Network for New Psychoactive Substance Identification: The Case of Synthetic Cannabinoids in a Seized e-Liquid and Biological Samples

The comprehensive detection of new psychoactive substances, including synthetic cannabinoids along with their associated metabolites in biological samples, remains an analytical challenge. To detect these chemicals, untargeted approaches using appropriate bioinformatic tools such as molecular networks are useful, albeit it necessitates as a prerequisite the identification of a node of interest within the cluster. To illustrate it, we reported in this study the identification of synthetic cannabinoids and some of their metabolites in seized e-liquid, urine, and hair collected from an 18-year-old poisoned patient hospitalized for neuropsychiatric disorders. A comprehensive analysis of the seized e-liquid was performed using gas chromatography coupled with electron ionization mass spectrometry, 1H NMR, and liquid chromatography coupled with high resolution tandem mass spectrometry combined with data processing based on molecular network strategy. It allowed researchers to detect in the e-liquid known synthetic cannabinoids including MDMB-4en-PINACA, EDMB-4en-PINACA, MMB-4en-PINACA, and MDMB-5F-PICA. Compounds corresponding to transesterification of MDMB-4en-PINACA with pentenol, glycerol, and propylene glycol were also identified. Regarding the urine sample of the patient, metabolites of MDMB-4en-PINACA were detected, including MDMB-4en-PINACA butanoic acid, dihydroxylated MDMB-4en-PINACA butanoic acid, and glucurono-conjugated MDMB-4en-PINACA butanoic acid. Hair analysis of the patient allowed the detection of MDMB-4en-PINACA and MDMB-5F-PICA in the two investigated hair segments. This untargeted analysis of seized materials and biological samples demonstrates the utility of the molecular network strategy in identifying closely related compounds and metabolites of synthetic cannabinoids. It also emphasizes the need for developing strategies to anchor molecular networks, especially for new psychoactive substances.

Cannabinoids in Integumentary Wound Care: A Systematic Review of Emerging Preclinical and Clinical Evidence

This systematic review critically evaluates preclinical and clinical data on the antibacterial and wound healing properties of cannabinoids in integument wounds. Comprehensive searches were conducted across multiple databases, including CINAHL, Cochrane library, Medline, Embase, PubMed, Web of Science, and LILACS, encompassing records up to May 22, 2024. Eighteen studies met the inclusion criteria. Eleven were animal studies, predominantly utilizing murine models (n = 10) and one equine model, involving 437 animals. The seven human studies ranged from case reports to randomized controlled trials, encompassing 92 participants aged six months to ninety years, with sample sizes varying from 1 to 69 patients. The studies examined the effects of various cannabinoid formulations, including combinations with other plant extracts, crude extracts, and purified and synthetic cannabis-based medications administered topically, intraperitoneally, orally, or sublingually. Four animal and three human studies reported complete wound closure. Hemp fruit oil extract, cannabidiol (CBD), and GP1a resulted in complete wound closure in twenty-three (range: 5-84) days with a healing rate of 66-86% within ten days in animal studies. One human study documented a wound healing rate of 3.3 cm2 over 30 days, while three studies on chronic, non-healing wounds reported an average healing time of 54 (21-150) days for 17 patients by oral oils with tetrahydrocannabinol (THC) and CBD and topical gels with THC, CBD, and terpenes. CBD and tetrahydrocannabidiol demonstrated significant potential in reducing bacterial loads in murine models. However, further high-quality research is imperative to fully elucidate the therapeutic potential of cannabinoids in the treatment of bacterial skin infections and wounds. Additionally, it is crucial to delineate the impact of medicinal cannabis on the various phases of wound healing. This study was registered in PROSPERO (CRD42021255413).

Cannabinoids and monoaminergic system: implications for learning and memory

Cannabinoids and the endocannabinoid system (ECS) have been intensively studied for their neuroregulatory roles in the central nervous system (CNS), especially in regulating learning and memory. However, many experimental and clinical studies obtained conflicting results indicating a complex network of interaction underlying the regulation of learning and memory by different cannabinoids and the ECS. The ECS influences neuronal synaptic communications, and therefore may exert different regulation via their different impact on other neurotransmitters. The monoaminergic system includes a variety of neurotransmitters, such as dopamine, norepinephrine, and serotonin, which play important roles in regulating mood, cognition, and reward. The interaction among cannabinoids, ECS and the monoaminergic system has drawn particular attention, especially their contributions to learning and memory. In this review, we summarized the current understanding of how cannabinoids, ECS and the monoaminergic system contribute to the process of learning and memory, and discussed the influences of monoaminergic neurotransmission by cannabinoids and ECS during this process.

The State of Synthetic Cannabinoid Medications for the Treatment of Pain

Synthetic cannabinoids are compounds made in the laboratory to structurally and functionally mimic phytocannabinoids from the Cannabis sativa L. plant, including delta-9-tetrahydrocannabinol (THC). Synthetic cannabinoids (SCs) can signal via the classical endogenous cannabinoid system (ECS) and the greater endocannabidiome network, highlighting their signalling complexity and far-reaching effects. Dronabinol and nabilone, which mimic THC signalling, have been approved by the Food and Drug Administration (FDA) for treating nausea associated with cancer chemotherapy and/or acquired immunodeficiency syndrome (AIDS). However, there is ongoing interest in these two drugs as potential analgesics for a variety of other clinical conditions, including neuropathic pain, spasticity-related pain, and nociplastic pain syndromes including fibromyalgia, osteoarthritis, and postoperative pain, among others. In this review, we highlight the signalling mechanisms of FDA-approved synthetic cannabinoids, discuss key clinical trials that investigate their analgesic potential, and illustrate challenges faced when bringing synthetic cannabinoids to the clinic.

Impulsivity and self-harm behavior in patients with synthetic cannabinoids dependence

BACKGROUND

Synthetic cannabinoids (SCs) dependence is increasingly prevalent among young individuals globally, with limited understanding of their potential detrimental effects. Therefore, we conducted this comparative study to assess impulsivity and non-suicidal self-harm behavior in patients with SCs dependence.

SUBJECTS AND METHOD

We conducted this comparative, case-control study in the outpatient clinics of (Beni-suef University Hospital). We recruited 30 patients with SCs dependence and the 30 healthy subjects as a control group. Psychometric scales, including Addiction Severity Index (ASI), Barratt Impulsivity Scale-11 (BIS-11), Deliberate Self-harm Inventory-Short Version (DSHI), SCID I, SCID II, and drug urine screen, were applied to compare the two study arms.

RESULTS

DSHI-s scores were significantly higher between the two study arms (3.23 ± 4.97 vs. 0.0 ± 0.0, p < 0.001, for cases and controls, respectively). Similarly, the mean ± SD score of the BIS scale was significantly higher in cases 68.13 ± 9.75 compared to the control group (45.67 ± 5.12) with a statistically significant difference (p < 0.001). Using the regression analysis, we observed a significant positive linkage between age, duration of substance use, DSHI-s, and the Barratt scale.

CONCLUSION

Patients with synthetic cannabis addiction exhibited more impulsivity and self-harm behaviors compared to healthy controls. The adverse effects of substance use disorder escalated, notably in individuals classified as having severe addiction based on the Addiction Severity Index. Age and length of substance use were found to be potential factors influencing the level of impulsivity and self-harm actions.

Possible cannabinoid-induced lactic acidosis requiring emergent dialysis

Lactic acidosis is a common finding in the intensive care unit and is associated with increased mortality. We present the case of a 42-year-old male with alcohol use disorder and cirrhosis who developed sudden onset shortness of breath while smoking marijuana. He was found to have a lactic acid level of 25.6 mmol/L with a significant anion gap metabolic acidosis requiring emergent dialysis. He was hypertensive without evidence of tissue hypoperfusion. His profound type B lactic acidosis was primarily attributed to a rare manifestation of cannabinoid toxicity. At a clinic visit 3 months later, he was doing well and had not smoked marijuana since his discharge.

An Internet Snapshot Survey Assessing the sale of Synthetic Cannabinoid Receptor Agonists for use with Electronic Vaping Devices

INTRODUCTION

Synthetic cannabinoid receptor agonists (SCRAs) are associated with significant toxicity and are increasingly used in electronic vaping devices. We assessed the availability of SCRA vaping products to UK purchasers on the surface web.

METHODS

An internet snapshot survey was performed between October 2022 and January 2023 on 'google.com' using the search terms "buy c-liquid vape", "buy herbal incense vape liquid", "buy cannabis vape liquid", "buy hashish vape liquid", "buy K2 vape liquid".

RESULTS

62 websites selling 128 SCRA vaping brands were identified. Most were purportedly based in the USA (41 websites, 66%) and most sold other controlled substances. Purchase incentives offered included discreet packaging (38, 61%), discounts for bulk purchase (34, 55%) and tracked delivery (30, 48%). Many websites stated SCRA products were: not for human consumption (41, 66%), for research purposes only (15, 24%), or legal (28, 45%). Websites sold a median (IQR) of 16 (7-25) SCRA vaping brands. Almost all were bottles of vaping liquid (1220/1225, 99.6%). The most common bottle size was 5mL (60%), the median (IQR) total volume of SCRA liquid per sale was 50mL (10-200mL). Median (IQR) price was £3.39/mL (£2.01/mL- £5.29/mL). Price decreased with increasing volume purchased (£6.58/mL for ≤ 5mL, £1.60/mL for > 200mL).

CONCLUSION

SCRA vaping products are easily obtainable online, in both small and bulk quantities. Information provided to purchasers on safety and legality is lacking or misleading. Further studies are needed to confirm the chemistry of these products. Policymakers should consider steps to limit the potential harm caused by the purchase and use of these products.

Acute and subacute toxic effects of CUMYL-4CN-BINACA on male albino rats

PURPOSE

There is very little information about the toxicological and pathological effects of synthetic cannabinoids, which have cannabis-like properties. This study was carried out to histopathologically, hematologically, and biochemically determine the toxic effects of acute and subacute exposure to a novel synthetic cannabinoid 1-(4-cyanobutyl)-N-(2-phenylpropan-2-yl)indazole-3-carboxamide in internal organs of adult male rats.

METHODS

The cannabinoid was injected intraperitoneally at three doses (0.5, 1.0, and 2.0 mg/kg, body weight). The cannabinoid was administered to acute groups for 2 days and to subacute groups for 14 days. Observations were made for 14 days and various changes such as mortality, injury, and illness were recorded daily. Hematological and biochemical changes were evaluated and histopathological analyses in lung, liver, and kidney tissues were also performed.

RESULTS

No mortality was observed. It was observed that there were fluctuations in hematological and serum biochemical parameters. Among the oxidative stress parameters, significant decreases in superoxide dismutase, catalase levels and significant increases in lipid peroxidation levels were determined. Serious pathological changes such as necrosis, vacuolation, congestion, and fibrosis were observed in the internal organs in a dose-dependent and time-dependent manner. It was also found that the synthetic cannabinoid triggered apoptosis in the organs. The results demonstrated that the most affected organ by the cannabinoid was the kidney.

CONCLUSION

This study showed for the first time that CUMYL-4CN-BINACA adversely affects healthy male albino rats. It can be estimated that the abuse of the cannabinoid may harm human health in the same way.

Delineating the molecular mechanisms of hippocampal neurotoxicity induced by chronic administration of synthetic cannabinoid AB-FUBINACA in mice

Chronic use of synthetic cannabinoids (SCs) has been associated with cognitive and behavioural deficits and an increased risk of neuropsychiatric disorders. The underlying molecular and cellular mechanisms of the neurotoxic effects of long-term use of SCs have not been well investigated in the literature. Herein, we evaluated the in vivo effects of chronic administration of AB-FUBINACA on the hippocampus in mice. Our results revealed that the administration of AB-FUBINACA induced a significant impairment in recognition memory associated with histopathological changes in the hippocampus. These findings were found to be correlated with increased level of oxidative stress, neuroinflammation, and apoptosis markers, and reduced expression of brain-derived neurotrophic factor (BDNF), which plays an essential role in modulating synaptic plasticity integral for promoting learning and memory in the hippocampus. Additionally, we showed that AB-FUBINACA significantly decreased the expression of NR1, an important functional subunit of glutamate/NMDA receptors and closely implicated in the development of toxic psychosis. These findings shed light on the long-term neurotoxic effects of SCs on hippocampus and the underlying mechanisms of these effects. This study provided new targets for possible medical interventions to improve the treatment guidelines for SCs addiction.

Complexity of Translating Analytics to Recent Cannabis Use and Impairment

While current analytical methodologies can readily identify cannabis use, definitively establishing recent use within the impairment window has proven to be far more complex, requiring a new approach. Recent studies have shown no direct relationship between impairment and Δ9-tetra-hydrocannabinol (Δ9-THC) concentrations in blood or saliva, making legal "per se" Δ9-THC limits scientifically unjustified. Current methods that focus on Δ9-THC and/or metabolite concentrations in blood, saliva, urine, or exhaled breath can lead to false-positive results for recent use due to the persistence of Δ9-THC well outside of the typical 3-4 h window of potential impairment following cannabis inhalation. There is also the issue of impairment due to other intoxicating substances-just because a subject exhibits signs of impairment and cannabis use is detected does not rule out the involvement of other drugs. Compounding the matter is the increasing popularity of hemp-derived cannabidiol (CBD) products following passage of the 2018 Farm Bill, which legalized industrial hemp in the United States. Many of these products contain varying levels of Δ9-THC, which can lead to false-positive tests for cannabis use. Furthermore, hemp-derived CBD is used to synthesize Δ8-THC, which possesses psychoactive properties similar to Δ9-THC and is surrounded by legal controversy. For accuracy, analytical methods must be able to distinguish the various THC isomers, which have identical masses and exhibit immunological cross-reactivity. A new testing approach has been developed based on exhaled breath and blood sampling that incorporates kinetic changes and the presence of key cannabinoids to detect recent cannabis use within the impairment window without the false-positive results seen with other methods. The complexity of determining recent cannabis use that may lead to impairment demands such a comprehensive method so that irresponsible users can be accurately detected without falsely accusing responsible users who may unjustly suffer harsh, life-changing consequences.

The synthetic cannabinoids menace: a review of health risks and toxicity

Synthetic cannabinoids (SCs) are chemically classified as psychoactive substances that target the endocannabinoid system in many body organs. SCs can initiate pathophysiological changes in many tissues which can be severe enough to damage the normal functionality of our body systems. The majority of SCs-related side effects are mediated by activating Cannabinoid Receptor 1 (CB1R) and Cannabinoid Receptor 2 (CB2R). The activation of these receptors can enkindle many downstream signalling pathways, including oxidative stress, inflammation, and apoptosis that ultimately can produce deleterious changes in many organs. Besides activating the cannabinoid receptors, SCs can act on non-cannabinoid targets, such as the orphan G protein receptors GPR55 and GPR18, the Peroxisome Proliferator-activated Receptors (PPARs), and the Transient receptor potential vanilloid 1 (TRPV1), which are broadly expressed in the brain and the heart and their activation mediates many pharmacological effects of SCs. In this review, we shed light on the multisystem complications found in SCs abusers, particularly discussing their neurologic, cardiovascular, renal, and hepatic effects, as well as highlighting the mechanisms that intermediate SCs-related pharmacological and toxicological consequences to provide comprehensive understanding of their short and long-term systemic effects.

Exploring the therapeutic potential of natural compounds modulating the endocannabinoid system in various diseases and disorders: review

Cannabinoid receptors, endogenous cannabinoids (endocannabinoids), and the enzymes involved in the biosynthesis and degradation of the endocannabinoids make up the endocannabinoid system (ECS). The components of the ECS are proven to modulate a vast bulk of various physiological and pathological processes due to their abundance throughout the human body. Such discoveries have attracted the researchers' attention and emerged as a potential therapeutical target for the treatment of various diseases. In the present article, we reviewed the discoveries of natural compounds, herbs, herbs formula, and their therapeutic properties in various diseases and disorders by modulating the ECS. We also summarize the molecular mechanisms through which these compounds elicit their properties by interacting with the ECS based on the existing findings. Our study provides the insight into the use of natural compounds that modulate ECS in various diseases and disorders, which in turn may facilitate future studies exploiting natural lead compounds as novel frameworks for designing more effective and safer therapeutics.

Fluorinated-Squaramide Covalent Organic Frameworks for High-Performance and Interference-Free Extraction of Synthetic Cannabinoids

Synthetic cannabinoids (SCs), one of the largest groups of new psychoactive substances (NPSs), have emerged as a significant public health threat in different regions worldwide. Analyzing SCs in water samples is critical to estimate their consumption and control. However, due to their low background concentration and the coexistence of complex matrix, the selective and effective enrichment of SCs is still challenging. In this study, a series of fluorinated-squaramide-based covalent organic frameworks (COF: FSQ-2, FSQ-3, and FSQ-4) are synthesized, and the as-prepared FSQ-4 exhibits strong affinity to different SCs. The proper pore size (1.4 nm) and pre-located functional groups (hydrogen-bond donors, hydrogen-bond acceptors, and fluorophilic segments) work synergistically for efficient SCs capture. Remarkably, when coupled FSQ-4 with solid-phase microextraction (SPME), trace-level (part per trillion, 10-9 ) determination of 13 SCs can be easily achieved, representing one of the best results among NPS analyses, and the excellent extraction performance can be maintained under various interfering conditions.

Ultrasensitive electrochemiluminescence sensor for the detection of synthetic cannabinoids based on perovskite as coreaction accelerator and light-scattering effects of photonic crystals

As is common knowledge, a strong electrochemiluminescence (ECL) signal is required to ensure the high sensitivity of trace target detection. Here, a dual signal amplification strategy by integrating of perovskite and photonic crystal was fabricated for quantitative synthetic cannabinoids (AB-PINACA) detection based on Zr-connected PTCA and TCPP (PTCA-TCPP) with excellent ECL performance as luminophores. On the one hand, the co-reaction accelerator perovskite (LaCoO3) improved the effective electroactive area of the electrode and promoted the decomposition of K2S2O8, resulting in a stronger ECL signal value. On the other hand, polystyrene inverse opal (PIOPCs) formed after the swelling of PS microspheres not only taken advantage of the light scattering effect and excellent catalytic property of photonic crystals to amplify the ECL signal, but also could be used as a binder to fix LaCoO3 and PTCA-TCPP on the electrode surface to generate unprecedented ECL response and stable ECL signals. Subsequently, the detection substance AB-PINACA was loaded on the electrode surface via the amide bond with the luminophores PTCA-TCPP, thus quenching the ECL signal, so as to realize the sensitive detection of synthetic cannabinoids. Under the optimal conditions, the proposed sensor achieved highly sensitive AB-PINACA detection with a dynamic range from 1.0 × 10-12 to 1.0 × 10-3 g/L and the detection limit was 1.1 × 10-13 g/L, which had great application potential in the detection of synthetic cannabinoids.

Therapeutic Potential of Cannabinoids in Glaucoma

Glaucoma is a leading cause of irreversible blindness worldwide. To date, intraocular pressure (IOP) is the only modifiable risk factor in glaucoma treatment, but even in treated patients, the disease can progress. Cannabinoids, which have been known to lower IOP since the 1970s, have been shown to have beneficial effects in glaucoma patients beyond their IOP-lowering properties. In addition to the classical cannabinoid receptors CB1 and CB2, knowledge of non-classical cannabinoid receptors and the endocannabinoid system has increased in recent years. In particular, the CB2 receptor has been shown to mediate anti-inflammatory, anti-apoptotic, and neuroprotective properties, which may represent a promising therapeutic target for neuroprotection in glaucoma patients. Due to their vasodilatory effects, cannabinoids improve blood flow to the optic nerve head, which may suggest a vasoprotective potential and counteract the altered blood flow observed in glaucoma patients. The aim of this review was to assess the available evidence on the effects and therapeutic potential of cannabinoids in glaucoma patients. The pharmacological mechanisms underlying the effects of cannabinoids on IOP, neuroprotection, and ocular hemodynamics have been discussed.

Advances in urinary biomarker research of synthetic cannabinoids

New psychoactive substances (NPS) are chemical compounds designed to mimic the action of existing illicit recreational drugs. Synthetic cannabinoids (SCs) are a subclass of NPS which bind to the cannabinoid receptors, CB1 and CB2, and mimic the action of cannabis. SCs have dominated recent NPS seizure reports worldwide. While urine is the most common matrix for drug-of-abuse testing, SCs undergo extensive Phase I and Phase II metabolism, resulting in almost undetectable parent compounds in urine samples. Therefore, the major urinary metabolites of SCs are usually investigated as surrogate biomarkers to identify their consumption. Since seized urine samples after consuming novel SCs may be unavailable in a timely manner, human hepatocytes, human liver microsomes and human transporter overexpressed cell lines are physiologically-relevant in vitro systems for performing metabolite identification, metabolic stability, reaction phenotyping and transporter experiments to establish the disposition of SC and its metabolites. Coupling these in vitro experiments with in vivo verification using limited authentic urine samples, such a two-pronged approach has proven to be effective in establishing urinary metabolites as biomarkers for rapidly emerging SCs.