Chemistry and Pharmacology of Delta-8-Tetrahydrocannabinol.

Cannabis sativa is one of the oldest plants utilized by humans for both economic and medical purposes. Although the use of cannabis started millennia ago in the Eastern hemisphere, its use has moved and flourished in the Western nations in more recent centuries. C. sativa is the source of psychoactive cannabinoids that are consumed as recreational drugs worldwide. The C21 aromatic hydrocarbons are restricted in their natural occurrence to cannabis (with a few exceptions). Delta-9-tetrahydrocannabinol (Δ9-THC) is the main psychoactive component in cannabis, with many pharmacological effects and various approved medical applications. However, a wide range of side effects are associated with the use of Δ9-THC, limiting its medical use. In 1966, another psychoactive cannabinoid, Delta-8-tetrahydrocannabinol (Δ8-THC) was isolated from marijuana grown in Maryland but in very low yield. Δ8-THC is gaining increased popularity due to its better stability and easier synthetic manufacturing procedures compared to Δ9-THC. The passing of the U.S. Farm Bill in 2018 led to an increase in the sale of Δ8-THC in the United States. The marketed products contain Δ8-THC from synthetic sources. In this review, methods of extraction, purification, and structure elucidation of Δ8-THC will be presented. The issue of whether Δ8-THC is a natural compound or an artifact will be discussed, and the different strategies for its chemical synthesis will be presented. Δ8-THC of synthetic origin is expected to contain some impurities due to residual amounts of starting materials and reagents, as well as side products of the reactions. The various methods of analysis and detection of impurities present in the marketed products will be discussed. The pharmacological effects of Δ8-THC, including its interaction with CB1 and CB2 cannabinoid receptors in comparison with Δ9-THC, will be reviewed.

Adolescent Δ8-THC and Marijuana Use in the US.

Importance: Gummies, flavored vaping devices, and other cannabis products containing psychoactive hemp-derived Δ8-tetrahydrocannabinol (THC) are increasingly marketed in the US with claims of being federally legal and comparable to marijuana. National data on prevalence and correlates of Δ8-THC use and comparisons to marijuana use among adolescents in the US are lacking. Objective: To estimate the self-reported prevalence of and sociodemographic and policy factors associated with Δ8-THC and marijuana use among US adolescents in the past 12 months. Design, Setting, and Participants: This nationally representative cross-sectional analysis included a randomly selected subset of 12th-grade students in 27 US states who participated in the Monitoring the Future Study in-school survey during February to June 2023. Exposures: Self-reported sex, race, ethnicity, and parental education; census region; state-level adult-use (ie, recreational) marijuana legalization (yes vs no); and state-level Δ8-THC policies (regulated vs not regulated). Main Outcomes and Measures: The primary outcome was self-reported Δ8-THC and marijuana use in the past 12 months (any vs no use and number of occasions used). Results: In the sample of 2186 12th-grade students (mean age, 17.7 years; 1054 [48.9% weighted] were female; 232 [11.1%] were Black, 411 [23.5%] were Hispanic, 1113 [46.1%] were White, and 328 [14.2%] were multiracial), prevalence of self-reported use in the past 12 months was 11.4% (95% CI, 8.6%-14.2%) for Δ8-THC and 30.4% (95% CI, 26.5%-34.4%) for marijuana. Of those 295 participants reporting Δ8-THC use, 35.4% used it at least 10 times in the past 12 months. Prevalence of Δ8-THC use was lower in Western vs Southern census regions (5.0% vs 14.3%; risk difference [RD], -9.4% [95% CI, -15.2% to -3.5%]; adjusted risk ratio [aRR], 0.35 [95% CI, 0.16-0.77]), states in which Δ8-THC was regulated vs not regulated (5.7% vs 14.4%; RD, -8.6% [95% CI, -12.9% to -4.4%]; aRR, 0.42 [95% CI, 0.23-0.74]), and states with vs without legal adult-use marijuana (8.0% vs 14.0%; RD, -6.0% [95% CI, -10.8% to -1.2%]; aRR, 0.56 [95% CI, 0.35-0.91]). Use in the past 12 months was lower among Hispanic than White participants for Δ8-THC (7.3% vs 14.4%; RD, -7.2% [95% CI, -12.2% to -2.1%]; aRR, 0.54 [95% CI, 0.34-0.87]) and marijuana (24.5% vs 33.0%; RD, -8.5% [95% CI, -14.9% to -2.1%]; aRR, 0.74 [95% CI, 0.59-0.94]). Δ8-THC and marijuana use prevalence did not differ by sex or parental education. Conclusions and Relevance: Δ8-THC use prevalence is appreciable among US adolescents and is higher in states without marijuana legalization or existing Δ8-THC regulations. Prioritizing surveillance, policy, and public health efforts addressing adolescent Δ8-THC use may be warranted.

Development and Validation of a GC-FID Method for the Quantitation of Δ 8-Tetrahydrocannabinol and Impurities Found in Synthetic Δ 8-Tetrahydrocannabinol and Vaping Products.

Concerns about health hazards associated with the consumption of trans-delta-8-tetrahydrocannabinol products were highlighted in public health advisories from the U. S. Food and Drug Administration and U. S. Centers for Disease Control and Prevention. Simple and rapid quantitative methods to determine trans-delta-8-tetrahydrocannabinol impurities are vital to analyze such products. In this study, a gas chromatography-flame ionization detection method was developed and validated for the determination of delta-8-tetrahydrocannabinol and some of its impurities (recently published) found in synthesized trans-delta-8-tetrahydrocannabinol raw material and included olivetol, cannabicitran, Δ 8-cis-iso-tetrahydrocannabinol, Δ 4-iso-tetrahydrocannabinol, iso-tetrahydrocannabifuran, cannabidiol, Δ 4,8-iso-tetrahydrocannabinol, Δ 8-iso-tetrahydrocannabinol, 4,8-epoxy-iso-tetrahydrocannabinol, trans-Δ 9-tetrahydrocannabinol, 8-hydroxy-iso-THC, 9α-hydroxyhexahydrocannabinol, and 9ß-hydroxyhexahydrocannabinol. Validation of the method was assessed according to the International Council for Harmonization guidelines and confirmed linearity with R2 ≥ 0.99 for all the target analytes. The limit of detection and limit of quantitation were 1.5 and 5 µg/mL, respectively, except for olivetol, which had a limit of detection of 3 µg/mL and a limit of quantitation of 10 µg/mL. Method precision was calculated as % relative standard deviation and the values were less than 8.4 and 9.9% for the intraday precision and inter-day precision, respectively. The accuracy ranged from 85 to 118%. The method was then applied to the analysis of 21 commercially marketed vaping products claiming to contain delta-8-tetrahydrocannabinol. The products analyzed by this method have various levels of these impurities, with all products far exceeding the 0.3% of trans-Δ 9-tetrahydrocannabinol limit for hemp under the Agriculture Improvement Act of 2018. The developed gas chromatography-flame ionization detection method can be an important tool for monitoring delta-8-tetrahydrocannabinol impurities in commercial products.

Aproximación a la evaluación de la potencia de la resina de cannabis en Madrid: ¿Un riesgo para la salud? / An approach to the evaluation of the potency of cannabis resin in Madrid: A health hazard?

El presente estudio investiga la concentración de Delta(9)-tetrahidrocannabinol (THC), cannabidiol (CBD) y cannabinol (CBN) en 60 muestras de resina de cannabis adquiridas en las calles de Madrid y su potencial riesgo para la salud del consumidor. Adicionalmente, estudiamos la posible asociación entre la potencia de las muestras y sus características organolépticas. El análisis de cannabinoides se llevó a cabo mediante cromatografía líquida de alta resolución (RP-HPLC-UV). Atendiendo al contenido en THC se estableció una escala de potencia para clasificar las muestras. El 76,7% de las muestras tenía un contenido en THC superior al 15%, esta potencia las cataloga como drogas de Grado I con “riesgo inaceptable” para la salud. El 36,7% de las muestras presentaron un contenido medio en THC del 28,8% (potencia muy alta). El contenido medio en CBD fue del 5% y el de CBN 1,74%; ambas ratios, CBD/THC y CBN/THC, mostraron una correlación negativa con la potencia. Al investigar la posible asociación entra potencia y características organolépticas, se observó que las muestras que presentaban a la vez una textura pegajosa, una elasticidad alta y un color marrón claro, tenían una potencia muy alta, con un contenido medio en THC del 28.7%. Nuestro estudio muestra que el contenido en THC de la mayoría de la resina de cannabis que puede adquirirse en Madrid es superior al 15% y supone un elevado riesgo para la salud. Adicionalmente, demostramos por primera vez que solo aquellas muestras con una potencia muy alta pueden asociarse directamente con ciertas características organolépticas. (AU)

The present study investigates the concentration of Delta (9)-tetrahidrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) in 60 samples of cannabis resin acquired on the streets of Madrid region and its potential danger to consumers’ health. Additionally, we study the possible correlation between the potency of samples and their organoleptic characteristics. The analysis of cannabinoids was carried out using a high performance liquid chromatography (RP-HPLC-UV). To classify samples, a strength scale based on THC content was established. THC content in 76.7% of the samples was higher than 15%. This potency allows these samples to be classified as Schedule I or drugs with “unacceptable risk” for human health. THC content in 36.7% of the samples was 28.8% on average, which means very high potency. The mean CBD content was 5%, while the correlation between the CBD/THC ratio and potency was negative. The mean content of CBN was 1.74% and the CBN/THC ratio also showed a negative correlation in respect to potency. When investigating the possible correlation between sample potency and organoleptic characteristics, those samples which simultaneously presented sticky texture, high elasticity and light brown colour had very high potency, with an average THC content of 28.7%. Our study shows that the THC content of most of the cannabis that can be purchased in Madrid region is over 15% and poses a health hazard. Additionally, we demonstrate for the first time that only those samples with very high potency can be directly associated with certain organoleptic characteristics. (AU)

Two new 22-membered macrolides from Streptomyces sp. HU210.

Two new 22-membered macrolide metabolites, phthoramycins B (1) and C (2), were isolated from the fermentation broth of Streptomyces sp. HU210. Their structures were elucidated based on extensive spectroscopic techniques including 1D, 2D NMR and HRESIMS data. Compounds 1 and 2 showed moderate cytotoxic activity against human leukemia cell line K562 and lung carcinoma cell line A549.

Cis-Δ9-tetrahydrocannabinolic acid occurrence in Cannabis sativa L.

Cannabidiolic acid (CBDA) and trans-Δ9-tetrahydrocannabinolic acid (trans-Δ9-THCA) are known to be the major phytocannabinoids in Cannabis sativa L., along with their decarboxylated derivatives cannabidiol (CBD) and trans-Δ9-tetrahydrocannabinol (trans-Δ9-THC). The cis isomer of Δ9-THC has been recently identified, characterized and quantified in several Cannabis sativa varieties, which had been heated (decarboxylated) before the analysis. Since decarboxylation alters the original phytocannabinoids composition of the plant, this work reports the identification and characterization of the carboxylated precursor cis-Δ9-THCA. The compound was also synthesized and used as analytical standard for the development and validation of a liquid chromatography coupled to high resolution mass spectrometry-based method for its quantification in ten Cannabis sativa L. samples from different chemotypes. The highest concentrations of cis-Δ9-THCA were found in CBD-rich varieties, lower levels were observed in cannabigerol (CBG)-rich varieties (chemotype IV) and in those varieties with a balanced level of both CBD and THC (chemotype III), while its levels were not detectable in cannabichromene (CBC)-rich varieties (chemotype VI). The presence of the cis isomer of THC and THCA raises the question on whether to include or not this species in the calculation of the total amount of THC to classify a cannabis variety as a drug-type or a fiber-type (hemp).

Unexpected short- and long-term effects of chronic adolescent HU-210 exposure on emotional behavior.

Chronic adolescent cannabinoid receptor agonist exposure has been shown to lead to persistent increases in depressive-like behaviors. This has been a key obstacle to the development of cannabinoid-based therapeutics. However, most of the published work has been performed with only three compounds, namely Δ9-tetrahydrocannabinol, CP55,940 and WIN55,212-2. Hypothesizing that different compounds may lead to distinct outcomes, we herein used the highly potent CB1R/CB2R full agonist HU-210, and first aimed at replicating cannabinoid-induced long-lasting effects, by exposing adolescent female Sprague-Dawley rats to increasing doses of HU-210, for 11 days and testing them at adulthood, after a 30-day drug washout. Surprisingly, HU-210 did not significantly impact adult anxious- or depressive-like behaviors. We then tested whether chronic adolescent HU-210 treatment resulted in short-term (24h) alterations in depressive-like behavior. Remarkably, HU-210 treatment simultaneously induced marked antidepressant- and prodepressant-like responses, in the modified forced swim (mFST) and sucrose preference tests (SPT), respectively. Hypothesizing that mFST results were a misleading artifact of HU-210-induced behavioral hyperreactivity to stress, we assessed plasmatic noradrenaline and corticosterone levels, under basal conditions and following an acute swim-stress episode. Notably, we found that while HU-210 did not alter basal noradrenaline or corticosterone levels, it greatly augmented the stress-induced increase in both. Our results show that, contrary to previously studied cannabinoid receptor agonists, HU-210 does not induce persisting depressive-like alterations, despite inducing marked short-term increases in stress-induced reactivity. By showing that not all cannabinoid receptor agonists may induce long-term negative effects, these results hold significant relevance for the development of cannabinoid-based therapeutics.

Safety and Efficacy of Lenabasum, a Cannabinoid Receptor Type 2 Agonist, in Patients with Dermatomyositis with Refractory Skin Disease: A Randomized Clinical Trial.

BACKGROUND: Treatment options are limited for skin disease in dermatomyositis. Lenabasum is a cannabinoid receptor type 2 agonist that triggers the resolution of inflammation. OBJECTIVE: The objective of this study was to evaluate the safety and efficacy of lenabasum in patients with refractory cutaneous dermatomyositis. DESIGN: This study was a single-center, double-blind, randomized, placebo-controlled phase 2 study conducted from July 2015 to August 2017. POPULATION: The population included subjects aged ≥18 years with at least moderately active dermatomyositis skin activity by Cutaneous Dermatomyositis Disease Area and Severity Index activity ≥ 14 and failure or intolerance to hydroxychloroquine. INTERVENTION: Participants received 20 mg lenabasum daily for 28 days and then 20 mg twice per day for 56 days or placebo. MAIN OUTCOMES AND MEASURES: The primary outcome was a change in Cutaneous Dermatomyositis Disease Area and Severity Index activity. Safety and other secondary efficacy assessments were performed till day 113. RESULTS: A total of 22 subjects were randomized to lenabasum (n = 11) or placebo (n = 11). No serious or severe adverse events were related to lenabasum, and no participants discontinued the study. The adjusted least-squares mean for Cutaneous Dermatomyositis Disease Area and Severity Index activity decreased more for lenabasum, and the difference was significant on day 113 (least-squares mean [standard error] difference = ‒6.5 [3.1], P = 0.038). Numerically greater improvements were seen in multiple secondary efficacy outcomes and biomarkers with lenabasum. CONCLUSION: Lenabasum treatment was well tolerated and was associated with greater improvement in Cutaneous Dermatomyositis Disease Area and Severity Index activity and multiple efficacy outcomes. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov, NCT02466243.

Review of delta-8-tetrahydrocannabinol (Δ8 -THC): Comparative pharmacology with Δ9 -THC.

The use of the intoxicating cannabinoid delta-8-tetrahydrocannabinol (Δ8 -THC) has grown rapidly over the last several years. There have been dozens of Δ8 -THC studies dating back over many decades, yet no review articles have comprehensively covered these findings. In this review, we summarize the pharmacological studies of Δ8 -THC, including receptor binding, cell signalling, in vivo cannabimimetic activity, clinical activity and pharmacokinetics. We give special focus to studies that directly compared Δ8 -THC to its more commonly studied isomer, Δ9 -THC. Overall, the pharmacokinetics and pharmacodynamics of Δ8 -THC and Δ9 -THC are very similar. Δ8 -THC is a partial agonist of the cannabinoid CB1 receptor and has cannabimimetic activity in both animals and humans. The reduced potency of Δ8 -THC in clinical studies compared with Δ9 -THC can be explained by weaker cannabinoid CB1 receptor affinity, although there are other plausible mechanisms that may contribute. We highlight the gaps in our knowledge of Δ8 -THC pharmacology where further studies are needed, particularly in humans.

Characterizing and Quantifying Extrahepatic Metabolism of (-)-Δ9-Tetrahydrocannabinol (THC) and Its Psychoactive Metabolite, (±)-11-Hydroxy-Δ9-THC (11-OH-THC).

(-)-Δ9-Tetrahydrocannabinol (THC) is the psychoactive constituent of cannabis, a drug recreationally consumed orally or by inhalation. Physiologically based pharmacokinetic (PBPK) modeling can be used to predict systemic and tissue exposure to THC and its psychoactive metabolite, (±)-11-hydroxy-Δ9-THC (11-OH-THC). To populate a THC/11-OH-THC PBPK model, we previously characterized the depletion clearance of THC (by CYP2C9) and 11-OH-THC (by UDP-glucuronosyltransferase (UGT), CYP3A, and CYP2C9) in adult human liver microsomes. Here we focused on quantifying extrahepatic depletion clearance of THC/11-OH-THC, important after oral (intestine) and inhalational (lung) consumption of THC as well as prenatal THC use (placenta and fetal liver). THC (500 nM) was metabolized in adult human intestinal microsomes (n = 3-5) by CYP2C9 [Vmax: 1.1 ± 0.38 nmol/min/mg; Michaelis-Menten constant (Km): 70 nM; intrinsic clearance (CLint): 15 ± 5.4 ml/min/mg; fraction metabolized (fm): 0.89 ± 0.31 at concentration ≪ 70 nM] and CYP3A (CLint: 2.0 ± 0.86 ml/min/mg; fm: 0.11 ± 0.050). 11-OH-THC (50 nM) was metabolized by CYP3A (CLint: 0.26 ± 0.058 ml/min/mg; fm: 0.51 ± 0.11) and UGT2B7 (CLint: 0.13 ± 0.027 ml/min/mg; fm: 0.25 ± 0.053). THC at 500 nM (CLint: 4.7 ± 0.22 ml/min/mg) and 11-OH-THC at 50 nM (CLint: 2.4 ± 0.13 ml/min/mg) were predominately (fm: 0.99 and 0.80, respectively) metabolized by CYP3A in human fetal liver microsomes (n = 3). However, we did not observe significant depletion of THC/11-OH-THC in adult lung, first trimester, second trimester, or term placentae microsomes. Using PBPK modeling and simulation, these data could be used in the future to predict systemic and tissue THC/11-OH-THC exposure in healthy and special populations. SIGNIFICANCE STATEMENT: This is the first characterization and quantification of (-)-Δ9-tetrahydrocannabinol (THC) and (±)-11-hydroxy-Δ9-THC (11-OH-THC) depletion clearance by cytochrome P450 and UDP-glucuronosyltransferase enzymes in extrahepatic human tissues: intestine, fetal liver, lung, and placenta. These data can be used to predict, through physiologically based pharmacokinetic modeling and simulation, systemic and tissue THC/11-OH-THC exposure after inhalational and oral THC use in both healthy and special populations (e.g., pregnant women).

Cannabinoid type 2 receptor (CB2R) distribution in dermatomyositis skin and peripheral blood mononuclear cells (PBMCs) and in vivo effects of LenabasumTM.

BACKGROUND: Lenabasum is a cannabinoid type 2 receptor (CB2R) reverse agonist that demonstrates anti-inflammatory effects in vivo and in vitro in dermatomyositis (DM) and is currently being investigated for therapeutic potential. The purpose of our study is to investigate CB2R distribution as well as the effects of lenabasum in DM. METHODS: Immunohistochemistry staining (IHC) was utilized to examine immune cell and cytokine production changes in lesional DM skin biopsies from lenabasum and placebo-treated patients. CB2R expression in various immune cell populations within DM skin was investigated with image mass cytometry (IMC), whereas flow cytometry elucidated CB2R expression in DM peripheral blood mononuclear cells (PBMCs) as well as cytokine production by CB2R-expressing cell populations. RESULTS: After 12 weeks of lenabasum treatment, IHC staining showed that CD4+ T cells, CB2R, IL-31, IFN-γ, and IFN-ß cytokines were downregulated. IFN-γ and IFN-ß mRNA decreased in lesional DM skin but not in PBMCs. IMC findings revealed that CB2R was upregulated in DM lesional skin compared to HC skin and DM PBMCs (p<0.05). In DM skin, CB2R was upregulated on dendritic cells, B cells, T cells, and macrophages while dendritic cells had the greatest expression in both DM skin and PBMCs (p<0.05). These CB2R+ cells in the skin produce IL-31, IL-4, IFN-γ, and IFN-ß. CONCLUSION: Our findings of differential CB2R expression based on location and cell type suggest modes by which lenabasum may exert anti-inflammatory effects in DM and highlights dendritic cells as potential therapeutic targets.

Popularity of Delta-8 THC on the Internet Across US States, 2021.

Objectives. To assess the popularity of an emergent drug, delta-8 tetrahydrocannabinol (THC), and compare interest levels between US states with or without legalized recreational cannabis. Methods. We used Google Trends to assess the growth of interest among delta-8 THC-related search terms from May 17, 2020, to May 9, 2021. We examined differences between states with or without legalized cannabis using state-level Google Trends data from February 13 to May 13, 2021, and policy data from the National Conference of State Legislatures. Results. Interest in delta-8 THC increased starting in mid-June 2020, with search volumes for delta-8 THC queries currently at 35% of the "marijuana" query. States where recreational cannabis is illegal had higher relative queries than did states with legalized recreational cannabis (52.3 vs 14.8; t = 40.9; P < .001). Conclusions. There has been rapid growth in interest in delta-8 THC. Findings between state policy contexts likely indicate delta-8 THC's role as a substitute good for delta-9 THC. Public Health Implications. Digital signals such as search volumes may point to an emergent use trend in the substance delta-8 THC. Further studies are needed to assess potential harms and correlates of delta-8 THC use. (Am J Public Health. 2022;112(2):296-299. https://doi.org/10.2105/AJPH.2021.306586).

Improved cyclobutyl nabilone analogs as potent CB1 receptor agonists.

In earlier work, we explored the SAR for the C3 side chain pharmacophore in the hexahydrocannabinol template represented by the drug nabilone, which resulted in the development of AM2389. In an effort for further optimization, we have merged features of nabilone and AM2389 and explored the C3 side chain with varying chain lengths and terminal substitutions. Of the compounds described here, a nabilone analog, AM8936, with the C6'-cyano-substituted side chain, was identified as the most successful analog capable of serving as a potential candidate for further development and a valuable tool for further in vivo studies. AM8936 behaved as a balanced and potent CB1 agonist in functional assays and was a potent and efficacious CB1 agonist in vivo. Our SAR studies are highlighted with the docking of AM8936 on the crystal structure of the hCB1 receptor.

Analytical and medico-legal problems linked to the presence of delta-8-tetrahydrocannabinol (delta-8-THC): Results from urine drug testing in Sweden.

During routine urine drug testing for cannabis use targeting delta-9-tetrahydrocannabinol carboxylic acid (delta-9-THC-COOH) at the Karolinska University Laboratory in Sweden, an unknown interfering peak was observed in the liquid-chromatographic-tandem mass-spectrometric (LC-MS/MS) confirmative analysis. The peak showed the same exact mass and most abundant fragments as delta-9-THC-COOH but a slightly shorter retention time, thereby not fulfilling all requirements for a positive identification. The analytical results suggested that it was a similar compound, and with access to reference material, it could be identified as the double bond isomer delta-8-THC-COOH. Delta-8-THC has recently become popular as a recreational drug, although its legality varies and is sometimes unclear. In Sweden, all THC isomers are classified substances. The slight difference in retention times was sufficient to distinguish the THC-COOH isomers in the routine LC-MS/MS method, but another LC method allowed better peak separation and individual quantification. At the Karolinska University Laboratory, delta-8-THC-COOH was first observed in April 2020, and the highest incidence was noted in June 2020 when it was present in 5.3% of all THC-COOH-positive samples. The incidence later decreased to today only occasional findings. Large differences in the relative presence of the isomers in the urine samples indicated different origin, for example, synthetically produced pure delta-8-THC, or mixtures of both THC isomers formed during combustion of cannabidiol (CBD). In conclusion, the appearance of delta-8-THC and other isomers on the recreational drug market risks causing analytical and medico-legal problems, due to confusion with delta-9-THC.

Prenatal Nicotine or Cannabis Exposure and Offspring Neurobehavioral Outcomes.

OBJECTIVE: To study the association between nicotine or cannabis metabolite presence in maternal urine and child neurodevelopmental outcomes. METHODS: We conducted a secondary analysis of two parallel multicenter randomized controlled trials of treatment for hypothyroxinemia or subclinical hypothyroidism among pregnant individuals enrolled at 8-20 weeks of gestation. All maternal-child dyads with a maternal urine sample at enrollment and child neurodevelopmental testing were included (N=1,197). Exposure was urine samples positive for nicotine (cotinine) or cannabis 11-nor-9-carboxy-delta-9-tetrahydrocannabinol [THC-COOH]) or both metabolites. Primary outcome was child IQ at 60 months. Secondary outcomes included cognitive, motor and language, attention, behavioral and social competency, and differential skills assessments at 12, 24, 36, and 48 months. Quantile regression analysis was performed with confounder adjustment. RESULTS: Of 1,197 pregnant individuals, 99 (8.3%) had positive cotinine samples and 47 (3.9%) had positive THC-COOH samples; 33 (2.8%) were positive for both. Groups differed in self-reported race and ethnicity, education, marital status, insurance, and thyroid status. Median IQ was similar between cotinine-exposed and -unexposed children (90 vs 95, adjusted difference in medians -2.47, 95% CI -6.22 to 1.29) and THC-COOH-exposed and -unexposed children (89 vs 95, adjusted difference in medians -1.35, 95% CI -7.76 to 5.05). In secondary outcome analysis, children with THC-COOH exposure compared with those unexposed had higher attention scores at 48 months of age (57 vs 49, adjusted difference in medians 6.0, 95% CI 1.11-10.89). CONCLUSIONS: Neither prenatal nicotine nor cannabis exposure was associated with a difference in IQ. Cannabis exposure was associated with worse attention scores in early childhood. Longitudinal studies assessing associations between child neurodevelopmental outcomes and prenatal nicotine and cannabis exposure with a focus on timing and quantity of exposure are needed. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT00388297.

Evaluation of the Possible Anticonvulsant Effect of Δ9-Tetrahydrocannabinolic Acid in Murine Seizure Models.

Introduction: The cannabinoid Δ9-tetrahydrocannabinolic acid (Δ9-THCA) has long been suggested in review articles and anecdotal reports to be anticonvulsant; yet, there is scant evidence supporting this notion. The objective of this study was to interrogate the anticonvulsant potential of Δ9-THCA in various seizure models-the Scn1a+/- mouse model of Dravet syndrome, the 6-Hz model of psychomotor seizures and the maximal electroshock (MES) model of generalized tonic-clonic seizures. Materials and Methods: We examined the effect of acute Δ9-THCA treatment against hyperthermia-induced seizures, and subchronic treatment on spontaneous seizures and survival in the Scn1a+/- mice. We also studied the effect of acute Δ9-THCA treatment on the critical current thresholds in the 6-Hz and MES tests using outbred Swiss mice. Highly purified Δ9-THCA was used in the studies or a mixture of Δ9-THCA and Δ9-THC. Results: We observed mixed anticonvulsant and proconvulsant effects of Δ9-THCA across the seizure models. Highly pure Δ9-THCA did not affect hyperthermia-induced seizures in Scn1a+/- mice. A Δ9-THCA/Δ9-THC mixture was anticonvulsant in the 6-Hz threshold test, but purified Δ9-THCA and Δ9-THC had no effect. Conversely, both Δ9-THCA and Δ9-THC administered individually were proconvulsant in the MES threshold test but had no effect when administered as a Δ9-THCA/Δ9-THC mixture. The Δ9-THCA/Δ9-THC mixture, however, increased spontaneous seizure severity and increased mortality of Scn1a+/- mice. Discussion: The anticonvulsant profile of Δ9-THCA was variable depending on the seizure model used and presence of Δ9-THC. Because of the unstable nature of Δ9-THCA, further exploration of Δ9-THCA through formal anticonvulsant drug development is problematic without stabilization. Future studies may better focus on determining the mechanisms by which combined Δ9-THCA and Δ9-THC alters seizure thresholds, as this may uncover novel targets for the control of refractory partial seizures.

Modulation of Recombinant Human T-Type Calcium Channels by Δ9-Tetrahydrocannabinolic Acid In Vitro.

Introduction: Low voltage-activated T-type calcium channels (T-type ICa), CaV3.1, CaV3.2, and CaV3.3, are opened by small depolarizations from the resting membrane potential in many cells and have been associated with neurological disorders, including absence epilepsy and pain. Δ9-tetrahydrocannabinol (THC) is the principal psychoactive compound in Cannabis and also directly modulates T-type ICa; however, there is no information about functional activity of most phytocannabinoids on T-type calcium channels, including Δ9-tetrahydrocannabinolic acid (THCA), the natural nonpsychoactive precursor of THC. The aim of this work was to characterize THCA effects on T-type calcium channels. Materials and Methods: We used HEK293 Flp-In-TREx cells stably expressing CaV3.1, 3.2, or 3.3. Whole-cell patch clamp recordings were made to investigate cannabinoid modulation of ICa. Results: THCA and THC inhibited the peak current amplitude CaV3.1 with pEC50s of 6.0±0.7 and 5.6±0.4, respectively. THC (1 µM) or THC produced a significant negative shift in half activation and inactivation of CaV3.1, and both drugs prolonged CaV3.1 deactivation kinetics. THCA (10 µM) inhibited CaV3.2 by 53%±4%, and both THCA and THC produced a substantial negative shift in the voltage for half inactivation and modest negative shift in half activation of CaV3.2. THC prolonged the deactivation time of CaV3.2, while THCA did not. THCA inhibited the peak current of CaV3.3 by 43%±2% (10 µM) but did not notably affect CaV3.3 channel activation or inactivation; however, THC caused significant hyperpolarizing shift in CaV3.3 steady-state inactivation. Discussion: THCA modulated T-type ICa currents in vitro, with significant modulation of kinetics and voltage dependence at low µM concentrations. This study suggests that THCA may have potential for therapeutic use in pain and epilepsy through T-type calcium channel modulation without the unwanted psychoactive effects associated with THC.

Potent T cell-mediated anti-inflammatory role of the selective CB2 agonist lenabasum in multiple sclerosis.

BACKGROUND: Lenabasum is a synthetic cannabinoid receptor type-2 (CB2) agonist able to exert potent anti-inflammatory effects, but its role on T cells remains unknown. OBJECTIVES: The present study was undertaken to investigate anti-inflammatory mechanisms of lenabasum in T lymphocyte subsets and its in vivo therapeutic efficacy in experimental autoimmune encephalomyelitis (EAE). METHODS: Mononuclear cells from 17 healthy subjects (HS) and 25 relapsing-remitting multiple sclerosis (RRMS) patients were activated in presence or absence of lenabasum and analysed by flow cytometry and qRT-PCR. EAE mice were treated with lenabasum, and clinical score and neuroinflammation were evaluated. RESULTS: Lenabasum significantly reduced TNF-a production from CD4+ T cells and CD8+ T cells in a dose-dependent manner in both HS and RRMS patients. In MS patients, lenabasum also reduced activation marker CD25 and inhibited IL-2 production from both T cell subsets and IFN-γ and IL-17 from committed Th1 and Th17 cells, respectively. These effects were blocked by the pretreatment with selective CB2 inverse agonist SR144528. In vivo treatment of EAE mice with lenabasum significantly ameliorated disease severity, reduced neuroinflammation and demyelination in spinal cord. CONCLUSION: Lenabasum exerts potent T cell-mediated immunomodulatory effects, suggesting CB2 as a promising pharmacological target to counteract neuroinflammation in MS.

Novel Δ8-Tetrahydrocannabinol Vaporizers Contain Unlabeled Adulterants, Unintended Byproducts of Chemical Synthesis, and Heavy Metals.

Cannabis e-cigarettes containing Δ8-tetrahydrocannabinol (Δ8-THC) produced synthetically from hemp-derived cannabidiol (CBD) have recently risen in popularity as a legal means of cannabis consumption, but questions surrounding purity and unlabeled additives have created doubts of their safety. Herein, NMR, GC-MS, and ICP-MS were used to analyze major components of 27 products from 10 brands, and it was determined none of these had accurate Δ8-THC labeling, 11 had unlabeled cutting agents, and all contained reaction side-products including olivetol, Δ4(8)-iso-tetrahydrocannabinol, 9-ethoxyhexahydrocannabinol, Δ9-tetrahydrocannabinol (Δ9-THC), heavy metals, and a novel previously undescribed cannabinoid, iso-tetrahydrocannabifuran.