Cannabis and Health Research: Rapid Progress Requires Innovative Research Designs

The Interplay of Exogenous Cannabinoid Use on Anandamide and 2-Arachidonoylglycerol in Anxiety: Results from a Quasi-Experimental Ad Libitum Study

The public is increasingly reporting using cannabis for anxiety relief. Both cannabis use and the endocannabinoid system have been connected with anxiety relief/anxiolytic properties, but these relationships are complex, and the underlying mechanisms for them are unclear. Background/Objectives: Work is needed to understand how the endocannabinoid system, including the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG), may be impacted by the main constituents of cannabis, Δ9-tetrahydrocannabinol (THC), and cannabidiol (CBD). Methods: The current study examined how the ab libitum use of products differing in THC and CBD affected AEA and 2-AG among 292 individuals randomly assigned to THC-dominant use (N = 92), CBD-dominant use (N = 97), THC + CBD use (N = 74), or non-use (N = 29). Results: The findings suggest that AEA levels do not change differently based on 4 weeks of cannabis use or by cannabinoid content, as AEA similarly increased across all conditions from study weeks 2 to 4. In contrast, AEA decreased at an acute administration session with product conditions containing any THC having greater AEA levels on average than the non-use condition. With regard to 2-AG, its levels appeared to primarily be affected by THC-dominant use, both acutely and over 4 weeks, when controlling for baseline cannabis use and examining study product use frequency among use conditions. Conclusions: Overall, the results continue to shed light on the complicated relationship between cannabinoid content and endocannabinoid production, and highlight the need for continued research on their interplay in human subjects.

Acute and Extended Anxiolytic Effects of Cannabidiol in Cannabis Flower: A Quasi-Experimental ad libitum Use Study

Objective: Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have varying pharmacological actions with differential effects on acute and extended affective states, incuding anxiety. We aimed to study these effects on anxiety in legal market forms of cannabis. Method: This study makes use of a nonequivalent control group quasiexperimental design. Forty-two participants with anxiety symptions who were not using cannabis were compared to 258 participants with anxiety symptoms who used cannabis flower (∼3-4 times per week). Participants who used cannabis were randomly assigned to one of three legal market cannabis conditions; THC-dominant (24% THC, <1% CBD), THC+CBD (12% THC, 12% CBD), or CBD-dominant (<1% THC, 24% CBD). Changes in anxiety symptoms over 4-weeks were measured by the Patient Global Impression of Change (PGIC) scale and the Depression, Anxiety, and Stress Scale (DASS). Acute changes in subjective mood immediately after cannabis use were measured by the Profile of Mood States (POMS) Elation, Tension, and Paranoia subscales and the Addiction Research Center Inventory intoxication scale. Results: While all participants reported anxiety reductions over the 4-week study on the PGIC (F=30.65, p<0.001) and DASS anxiety measures (F=115.88, p<0.001), ad libitum CBD-dominant cannabis use was associated with lower scores on the DASS anxiety subscale compared to THC-dominant use when accounting for frequency of use (difference=-1.03, SE=0.45, p=0.02). Similarly, acute CBD-dominant cannabis use was associated with lower scores on the POMS tension and paranoia subscales (POMS tension: CBD-dominant vs. THC-dominant: difference=-0.41 SE=0.1, p<0.001; CBD-dominant vs. THC+CBD: difference=-0.28, SE=0.07, p=0.04; POMS paranoia: CBD-dominant vs. THC-dominant: difference=-0.49, SE=0.1, p<0.001; CBD-dominant vs. THC+CBD: difference=-0.33, SE=0.09, p=0.01). Participants in all cannabis conditions experienced acute changes in positive mood and subjective drug effects. Conclusions: This study provides novel information on the impacts of legal market cannabis with varying ratios of THC to CBD in indviduals with anxiety symptoms. Findings suggest that THC did not increase anxiety and that CBD-dominant forms of cannabis were associated with acute tension reduction that may translate to longer-term reductions in anxiety symptoms. Clinical Trial Registration: NCT03491384.

Investigating the Relationship Between Cannabis Expectancies and Anxiety, Depression, and Pain Responses After Acute Flower and Edible Cannabis Use

Objective: Cannabis has been touted for a host of pharmacological and therapeutic effects and users commonly report reduced symptoms of physical and mental health conditions, including anxiety, depression, and chronic pain. While there is existing empirical evidence supporting these effects of cannabis use, little is known about the extent to which these effects result from pharmacological versus expectancy factors. We evaluated the associations between participants' cannabis expectancies and their acute self-reported reactions after using legal market forms of cannabis with varying levels of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) in three domains: anxiety, depression, and pain. Methods: Fifty-five flower and 101 edible cannabis users were randomly assigned and asked to purchase at a local dispensary one of three products containing varying levels of CBD and THC. Participants completed a baseline assessment where they reported expectancies about general health effects of cannabis use and an experimental mobile laboratory assessment where they administered their assigned products. Edible users also reported their domain-specific expectancies about cannabis use in improving anxiety, depression, and pain. Following administration, participants completed acute indicators of anxiety, depression, and pain operationalized through subjective acute tension, elation, and a single-item measure of pain. Results: Among flower users, more positive expectancies for cannabis to improve general health were correlated with greater reductions in tension at acute post-use. This finding was replicated among edible users. Unlike flower users, more positive expectancies for cannabis to improve general health were also correlated with greater increases in elation and greater reductions in pain among edible users. More positive expectancies for cannabis to improve depression and pain were also correlated with greater increases in elation and greater reductions in pain, respectively, among edible users. Conclusions: Cannabis users' expectancies significantly impacted some of the acute subjective effects of legal market cannabis products. Among both flower and edible users, consistent, significant expectancy effects were found. Results were consistent with prior findings and demonstrate the need to measure and control pre-existing expectancies in future research that involves cannabis administration. Clinical trial registration number: NCT03522103.

Cannabinoid Exposure and Subjective Effects of THC and CBD in Edible Cannabis Products

Background: The popularity of edible cannabis products continues to grow in states with legal cannabis access, but few studies have investigated the acute effects of these commercially available products. The present study sought to explore the effects of three commercially available edible products with different levels of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Methods: A sample of regular cannabis users (N=99) were evaluated. Fifty participants completed the study procedures in-person, whereas 49 participants completed the study procedures remotely via Zoom. Subjective effects and plasma cannabinoid levels (in-person participants only) were assessed before and 2 h after participants self-administered one of three products ad libitum: a THC-dominant edible product, a CBD-dominant edible product, or a THC+CBD edible product. Results: At the 2-h post-use assessment, among in-person participants, plasma THC and CBD levels were robustly correlated with self-reported milligrams of THC and CBD consumed, respectively. Across all three conditions, in-person and remote participants experienced (1) an increase in subjective intoxication and elation, (2) a decrease in tension, and (3) no change in paranoia from pre-use to post-use. At post-use, participants who used a CBD product reported less intoxication relative to participants who used a THC+CBD or THC-only product. Participants who used a THC+CBD product reported consuming less THC-and displayed lower plasma THC levels (in-person participants)-relative to participants who used a THC-only product, despite reporting similar levels of positive (intoxication, elation, liking) and psychotomimetic (paranoia, tension) effects. Psychotomimetic effects were very low among both in-person and remote participants across all three conditions, and there were no post-use differences across conditions. Conclusions: Findings suggest that experienced users who consumed a THC+CBD product reported similar levels of positive and psychotomimetic effects relative to those who consumed a THC-only product, despite consuming less THC and displaying lower plasma THC concentrations. Given the potential harms associated with acute cannabis reward and long-term THC exposure, further research is needed to establish whether edible cannabis products with CBD pose less risk to users. Future studies should examine whether these effects generalize to samples of infrequent users, who may have less experience with edible cannabis use. ClinicalTrials.gov ID: NCT03522103.

The impact of blunt use on smoking abstinence among Black adults: Secondary analysis from randomized controlled smoking cessation clinical trial

INTRODUCTION

People who smoke cigarettes are more likely than people who do not to use cannabis, including blunts, a tobacco product containing nicotine and marijuana. Blunts represent a challenge for cessation trials because nicotine could make stopping cigarettes more difficult. Few studies have examined the impact of blunt use on individuals actively engaged in a cigarette quit attempt.

METHODS

Blunt use was assessed at baseline, Weeks 4, 8, 12, 16, and 26 among Black adult people who smoke enrolled in a double-blind, placebo-controlled, randomized trial of varenicline (VAR, n = 300) versus placebo (PBO, n = 200) for smoking cessation. Participants were categorized as ever blunt (blunt use reported at any timepoint) versus non-blunt (no blunt use reported). The primary outcome was salivary cotinine-verified 7-day point prevalence smoking abstinence at Weeks 12 and 26. Logistic regression examined the effects of treatment and blunt use on abstinence.

RESULTS

75 participants (mean age 45.6 years (SD = 12.5, range: 22,80); 32 (42%) female) reported blunt use. Logistic regression analyses showed no treatment by blunt use interaction or significant main effect of blunt use on smoking abstinence at Weeks 12 or 26 (p > 0.05). After adjusting for treatment, those who used blunts had statistically similar odds of quitting at Week 12 (OR: 0.68, 95% CI: 0.31, 1.5) and Week 26 (OR: 0.84, 95% CI: 0.38, 1.87) as those who never used blunts during the study.

DISCUSSION

Blunt use had no statistically significant impact on cessation among participants in a smoking cessation clinical trial. Future trials are needed in which the target of cessation is all combustible products.

Effects of historical inequity and institutional power on cannabis research: Moving toward equity and inclusion

Given historical inequities in cannabis laws and policies, there is an obligation on the part of researchers and policy makers to actively work toward improving equity in cannabis research at a time when the field is rapidly expanding. We wish to propose a way forward for cannabis research that acknowledges this history of discrimination and misuse of institutional power and embraces equity and inclusion. This article provides a brief perspective on historical drug policy, recent legalization trends that have disproportionately benefitted some groups over others, and the repercussions of those trends for the cannabis research enterprise. In addition, it proposes five key actions in both policy and research domains that are necessary to move the field of cannabis research, and perhaps biomedical research in substance use more broadly, forward in a productive and inclusionary way. Specifically, recommendations focus on equity-focused legislation and policy, supporting the entry and retention of scientists of color into the field, engaging in more ethical research practices, and practicing intentionally inclusive recruitment of participants will help to move the field of cannabis research forward. These efforts will ensure that scientific gains are shared equitably moving forward.

A small clinical trial of vaporized cannabis for PTSD: suggestive results and directions for future study

The last few decades have seen increasing interest in the use of cannabis for post-traumatic stress disorder (PTSD). Recent attempts to evaluate the clinical efficacy of cannabis for PTSD were inconclusive and generalizability was limited by undesirable features of the study drug. The present clinical trial evaluated the effects of a commercially available chemovar that was delivered by vaporization. The study was designed as a randomized placebo-controlled cross-over study with three conditions; however, only five individuals completed the trial, and analysis of the placebo effect was not possible. Results identified positive changes consistent with medium-sized within-subject effects for cannabis in the treatment of PTSD. Positive trending results and high patient need mandate future studies of cannabis for the treatment of PTSD.

Pharmacokinetics of delta-9-tetrahydrocannabinol following acute cannabis smoke exposure in mice; effects of sex, age, and strain

Increased use of cannabis and cannabinoids for recreational and medical purposes has led to a growth in research on their effects in animal models. The majority of this work has employed cannabinoid injections; however, smoking remains the most common route of cannabis consumption. To better model real-world cannabis use, we exposed mice to cannabis smoke to establish the pharmacokinetics of Δ9THC and its metabolites in plasma and brain. To determine the time course of Δ9THC and two major metabolites [11-hydroxy-delta-9-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (11-COOH-THC)], male and female C57BL/6J mice were exposed to smoke from sequentially burning 5 cannabis cigarettes. Following smoke exposure, trunk blood and brains were collected at 6 time points (10-240 min). Plasma and brain homogenates were analyzed for Δ9THC and metabolites using a validated ultraperformance liquid chromatography-tandem mass spectrometry method. To assess effects of age, sex, and mouse strain, we exposed mice of four strains (C57BL/6J, FVB, Swiss Webster, and 129S6/SvEv, aged 4-24 months) to cannabis using the same smoke regimen. Samples were collected 10 and 40 min following exposure. Lastly, to assess effects of dose, C57BL/6J mice were exposed to smoke from burning 3 or 5 cannabis cigarettes, with samples collected 40 min following exposure. The pharmacokinetic study revealed that maximum plasma Δ9THC concentrations (Cmax) were achieved at 10 and 40 min for males and females, respectively, while Cmax for brain Δ9THC was observed at 20 and 40 min for males and females, respectively. There were no age or strain differences in plasma Δ9THC concentrations at 10 or 40 min; however, 129S6/SvEv mice had significantly higher brain Δ9THC concentrations than FVB mice. Additionally, 3 cigarettes produced significantly lower plasma 11-COOH-THC concentrations compared to 5 cigarettes, although dose differences were not evident in plasma or brain concentrations of Δ9THC or 11-OH-THC. Across all experiments, females had higher levels of 11-COOH-THC in plasma compared to males. The results reveal robust sex differences in Δ9THC pharmacokinetics, and lay the groundwork for future studies using mice to model the pharmacodynamics of smoked cannabis.

A daily diary investigation of cannabis use and its diet and exercise correlates

Background

The increasing availability of legal-market cannabis products has raised many questions about potential harms and benefits of increased use. In particular, concerns have been raised about the possible negative impact of cannabis use on behavioral determinants of obesity and chronic disease, including diet and exercise. However, previous research is mixed and has largely relied on cross-sectional survey data and coarse measurements of cannabis use, underscoring the need for more rigorous research designs.

Purpose

The present study utilized longitudinal daily diary data to assess whether exercise and diet patterns differed between cannabis users and non-users and, within cannabis users, whether legal-market cannabis use, diet, and exercise covaried within individuals across time and based on cannabinoid content.

Methods

A sample of 98 participants (77 cannabis users, 21 non-users) completed a baseline appointment and a 30-day daily diary study assessing their daily cannabis use, diet, and exercise. Cannabis users were quasi-randomly assigned to use either a THC-dominant flower product (n = 36) or a CBD-containing flower product (n = 41) ad libitum over the course of the daily diary study. Participants were between the ages of 21 and 41 (M = 29.28) and were majority male (61.2%).

Results

At baseline, there were no differences in BMI or exercise behavior between users and non-users. Likelihood of exercising and exercise minutes per day over the 30-day period also did not differ between users and non-users, nor did these outcomes differ on cannabis use vs. non-use days among cannabis using participants. In contrast, there was some evidence for a relationship between cannabis use and dietary measures. At baseline, non-users scored higher on the Healthy Eating Index than users. Daily data also indicated that users consumed marginally more salty snacks and fast food per day relative to non-users, and users consumed more fruits/vegetables and marginally more salty snacks on cannabis use days vs. non-use days. Interestingly, among users, no associations were dependent on the cannabinoid content of their assigned product.

Conclusion

Findings suggest little association between cannabis use and exercise but underscore the need for further research on how cannabis use may impact dietary patterns. Future research should examine the impact of cannabis on non-behavioral pathways to obesity and chronic disease (e.g., metabolism).

Protocol for a mobile laboratory study of co-administration of cannabis concentrates with a standard alcohol dose in humans

Cannabis is commonly used among people who drink alcohol, yet evidence on acute effects of co-use is conflicting. Two important variables that may influence the effects of cannabis and alcohol are cannabinoid content (i.e., the ratio of cannabidiol [CBD] and 9-tetrahydrocannabinol [THC]) as well as the order of use (i.e., cannabis before alcohol vs. alcohol before cannabis). Research is mixed regarding the acute imapct of cannabis on alcohol consumption and intoxication, with some studies suggesting additive effects of alcohol and cannabis, and others demonstrating negligible effects of combining these substances. Further complicating this, high-THC-content cannabis concentrates are increasingly popular on the legal-market, but to our knowledge, no studies have explored concentrate and alcohol co-use. In addition to cannabinoid content, order of use may influence intoxication and other acute effects, but is also understudied. Co-use studies typically administer a fixed dose of alcohol before cannabis, and there is a lack of data on the acute effects of cannabis before alcohol. Thus, there is a need for experimental co-use studies exploring the impact of cannabinoid content (particularly of highly potent cannabis concentrates) and order effects on intoxication. This study uses a federally-compliant mobile laboratory procedure to explore the effects of co-administration of legal-market cannabis concentrates with a moderate alcohol dose (.8g/kg) in a sample of community participants who regularly use alcohol and cannabis. The study will also explore alcohol and cannabis order effects (cannabis before alcohol vs. alcohol before cannabis). Outcomes are objective intoxication (measured using blood cannabinoid level, heart rate, psychomotor performance and breath alcohol level [BrAC]) and subjective intoxication (assessed via self-report measures). Overall, this study may influence harm-reduction recommendations for individuals who drink alcohol and use cannabis.

Differences in Attitudes Toward Medical Cannabis With Humanized Patient Scenarios

Introduction Attitudes toward medical cannabis are shaped by a number of factors, such as religion, previous use, and political affiliation. Individuals with less supportive beliefs toward cannabis, in general, may be more open to its therapeutic applications in a humanized patient scenario (PS). Methods A modified medical cannabis attitude scale was used to measure participants' attitudes toward medical cannabis. Two humanized patient scenarios were presented to the participants, and their level of agreement with the patient having access to medical cannabis was measured. After the scales were standardized, a Wilcoxon signed-rank test (WSR) was utilized to determine whether a difference between medical cannabis attitudes and approval of medical cannabis use in the humanized PS exists. Results A total of 645 participants completed the full survey and were included in the data analysis. Most participants were supportive of the patients in the humanized scenarios having access to medical cannabis; 76.1% and 75.7% of respondents, in each of the scenarios, selected the highest level of approval. There was a significantly higher approval for medical cannabis with the PS than attitudes toward medical cannabis in general (Z=-17.415, p<0.0005). Conclusion Individuals were more supportive of patient access to medical cannabis when exposed to humanized PS than their general attitudes toward medical cannabis indicated. Applying the results of this current research, a viable plan to reduce the stigma surrounding cannabis is to use patient testimonials in public-facing advocacy efforts regarding medical cannabis.

Cannabis Seeds Authentication by Chloroplast and Nuclear DNA Analysis Coupled with High-Resolution Melting Method for Quality Control Purposes

Background: Cannabis plants and their seed have been used in many cultures as a source of medicine and feeding during history. Today, there is an increasing demand for cannabis seeds for medical use. Moreover, a seed sales market with no legal regulations has also grown. This may pose some issues if a quality control is not set in place. Identification of cannabis strains is important for quality control purposes in a nonregulated growing market and in cases of illegal traffic and medical use. Owing to the high price as a pharmacological drug, commercial products of cannabis plants and seeds for medical users are often subjected to adulterations, either when packing or distributing certified seeds in the market. Materials and Methods: Cannabis commercial seeds and cannabis seeds for medical use were analyzed with high-resolution melting (HRM) analysis using barcoding markers. Humulus lupulus L. plants from a local market were used as outgroup control. DNA barcoding uses specific regions of the genome to identify differences in the genetic sequence of conserved regions such as internal transcribed spacer (ITS) and rbcL. DNA barcoding data can be generated with real-time polymerase chain reaction combined with HRM analysis to distinguish specific conserved DNA regions of closely related species. HRM analysis is the method of choice for rapid analysis of sequence variation. Results: The melting temperature (Tm) of homogeneous packages was consistent with single genotypes. However, packages containing contaminating seeds showed Tm differences of 0.2°C on average. Conclusions: An effective, rapid, and low-cost method based on ITS nuclear DNA and on chloroplast rbcL regions for screening and detection of contamination in commercial cannabis seeds was developed and applied for the analysis of different samples. This approach can be used as a quality control tool for cannabis seeds or other plant material.

The cannabidiol and marijuana research expansion act: Promotion of scientific knowledge to prevent a national health crisis

While the use of medical and recreational cannabis is rapidly expanding under state jurisdiction, the convolution of federal regulations is obstructing research progress to the detriment of healthcare equity and the protection of vulnerable populations, such as the underaged. U.S. Senate bill S.253 is designed to accelerate the development of trusted preclinical and clinical principles based on scientific data to guide physicians in their daily practice, inform lawmakers, and thereby protect public health. This goes together with a reinforcement of the legal protection that practitioners have acquired over years of litigation with the federal government when working with their patients. S.253 supports open communication between physicians and their patients when discussing cannabis as a treatment option. The bill passed the U.S. Senate on March 24, 2022.

Funding

This work was supported by intramural funding (NYIT College of Osteopathic Medicine) to the corresponding author, Dr. Joerg R. Leheste.

Cannabis Use and Resting State Functional Connectivity in the Aging Brain

Several lines of evidence suggest that older adults (aged 65+) sharply increased their cannabis use over the last decade, highlighting a need to understand the effects of cannabis in this age group. Pre-clinical models suggest that cannabinoids affect the brain and cognition in an age-dependent fashion, having generally beneficial effects on older animals and deleterious effects on younger ones. However, there is little research on how cannabis affects the brains of older adults or how older adults differ from younger adults who use cannabis. Resting state functional connectivity (rsFC) measures provide sensitive metrics of age-related cognitive decline. Here we compared rsFC in older adults who are either regular users of cannabis or non-users. We found stronger connectivity between sources in the hippocampus and parahippocampal cortex, and targets in the anterior lobes of the cerebellum in older adult cannabis users relative to non-users. A similar pattern of strengthened connectivity between hippocampal and cerebellar structures was also present in 25-35 year old non-users in comparison to 60-88 year old non-users. These findings suggest that future studies should examine both the potential risks of cannabinoids, as well as a potential benefits, on cognition and brain health for older adults.

Effects of cannabidiol in cannabis flower: Implications for harm reduction

Using a federally compatible, naturalistic at-home administration procedure, the present study examined the acute effects of three cannabis flower chemovars with different tetrahydrocannabinol (THC) to cannabidiol (CBD) ratios, in order to test whether chemovars with a higher CBD content produce different effects. Participants were randomly assigned to ad libitum administration of one of three chemovars (THC-dominant: 24% THC, 1% CBD; THC+CBD: 9% THC, 10% CBD; CBD-dominant: 1% THC, 23% CBD); 159 regular cannabis users (male = 94, female = 65) were assessed in a mobile pharmacology lab before, immediately after, and 1 h after ad libitum administration of their assigned chemovar. Plasma cannabinoids as well as positive (e.g., high, elation) and negative (e.g., paranoia and anxiety) subjective effects were assessed at each time points. Participants who used the CBD-dominant and THC + CBD chemovars had significantly less THC and more CBD in plasma samples compared to participants who used the THC-dominant chemovar. Further, the THC + CBD chemovar was associated with similar levels of positive subjective effects, but significantly less paranoia and anxiety, as compared to the THC-dominant chemovar. This is one of the first studies to examine the differential effects of various THC to CBD ratios using chemovars that are widely available in state-regulated markets. Individuals using a THC + CBD chemovar had significantly lower plasma THC concentrations and reported less paranoia and anxiety while also reporting similar positive mood effects as compared to individuals using THC only, which is intriguing from a harm reduction perspective. Further research is needed to clarify the harm reduction potential of CBD in cannabis products.

Cannabis and the Cancer Patient

Session 2 of the National Cancer Institute's Cannabis, Cannabinoids, and Cancer Research Workshop opened with testimony from a lymphoma survivor who detailed medicinal cannabis-related improvements in nausea, low appetite, insomnia, and mental health and the limited clinical counsel she received regarding cannabis use. Discussion next turned to the evolution of the legal landscape of cannabis in the United States, one in which state and federal laws frequently conflict and the Controlled Substance Act renders cannabis Schedule I. This legal climate creates conundrums for US medicinal cannabis researchers who contend with limited funding opportunities, avenues to source trial drug, and procedural red tape and for oncology clinicians who recommend medicinal cannabis to patients with some frequency while perceiving themselves as ill equipped to make such clinical recommendations. Ultimately, it creates challenges for cancer patients who find themselves turning to nonmedical and anecdotal information sources. The risks of cannabis use by the cancer patient were discussed next. These include infection, pharmacodynamic and pharmacokinetic drug-botanical interactions, cyclic nausea and vomiting, e-cigarette or vaping product use-associated illness, legal issues, and high cost. The session concluded with a broad survey of the research supporting oncologic cannabinoid use, conclusive evidence for chemotherapy-induced nausea and vomiting, and suggestive evidence for cancer-related pain.

Lipid-based formulations to increase cannabidiol bioavailability: In vitro digestion tests, pre-clinical assessment and clinical trial

Herein, medium-chain triglycerides (MCT), glyceryl monolinoleate (GML), and a self-emulsifying drug delivery system (SEDDS) for cannabidiol (CBD) delivery were compared using in vitro and in vivo (mouse and human) studies. In vitro digestion tests showed that SEDDS yielded the highest CBD recovery in the aqueous phase (86 ± 2%), followed by GML (13 ± 2%) and MCT (5.6% ± 0.8%). In vivo tests (mouse) revealed that SEDDS promoted the highest CBD exposure, exhibiting an area under the plasma concentration-time curve (AUC_0-6h) 1.48 times greater than GML and 3.97 times greater than that of the MCT formulation. A single-dose, open-label, crossover study performed in 11 volunteers showed that SEDDS increased CBD AUC_0-12h by 1.12 and 1.48 times in relation to GML and MCT, respectively. The in vitro-in vivo correlation was r² 0.75 for mice and r² 0.66 for humans. The AUC correlation between mice and humans was 0.98. Collectively, these results indicate that the lipid profile substantially influences CBD delivery and highlights the potential of the SEDDS and GML formulations as candidate solutions for increasing CBD AUC and bioavailability.

Genomic Evidence That Governmentally Produced Cannabis sativa Poorly Represents Genetic Variation Available in State Markets

The National Institute on Drug Abuse (NIDA) is the sole producer of Cannabis for research purposes in the United States, including medical investigation. Previous research established that cannabinoid profiles in the NIDA varieties lacked diversity and potency relative to the Cannabis produced commercially. Additionally, microsatellite marker analyses have established that the NIDA varieties are genetically divergent form varieties produced in the private legal market. Here, we analyzed the genomes of multiple Cannabis varieties from diverse lineages including two produced by NIDA, and we provide further support that NIDA's varieties differ from widely available medical, recreational, or industrial Cannabis. Furthermore, our results suggest that NIDA's varieties lack diversity in the single-copy portion of the genome, the maternally inherited genomes, the cannabinoid genes, and in the repetitive content of the genome. Therefore, results based on NIDA's varieties are not generalizable regarding the effects of Cannabis after consumption. For medical research to be relevant, material that is more widely used would have to be studied. Clearly, having research to date dominated by a single, non-representative source of Cannabis has hindered scientific investigation.

Advancing the science on cannabis concentrates and behavioural health

ISSUES

The Cannabis sativa L. plant contains hundreds of phytocannabinoids, but putatively of highest importance to public health risk is the psychoactive cannabinoid delta-9-tetrahydrocannabinol (THC), which is associated with risk for cannabis use disorder, affective disturbance, cognitive harm and psychomotor impairment. Recently, there has been an increase in the use and availability of concentrated cannabis products (or 'concentrates') that are made by extracting cannabinoids from the plant to form a product with THC concentrations as high as 90-95%. These products are increasingly popular nationwide. The literature on these widely available high potency concentrates is limited and there are many unknowns about their potential harms.

APPROACH

This review covers the state of the research on cannabis concentrates and behavioural health-related outcomes and makes recommendations for advancing the science with studies focused on accurately testing the risks in relation to critical public and behavioural health questions.

KEY FINDINGS

Data point to unique behavioural health implications of concentrate use. However, causal, controlled and representative research on the effects of cannabis concentrates is currently limited.

IMPLICATIONS

Future research is needed to explore chronic, acute and developmental effects of concentrates, as well as effects on pulmonary function. We also highlight the need to explore these relationships in diverse populations.

CONCLUSION

While the literature hints at the potential for these highly potent products to increase cannabis-related behavioural health harms, it is important to carefully design studies that more comprehensively evaluate the impact of concentrates on THC exposure and short- and long-term effects across user groups.

Cannabinoids and Terpenes: How Production of Photo-Protectants Can Be Manipulated to Enhance Cannabis sativa L. Phytochemistry

Cannabis sativa L. is cultivated for its secondary metabolites, of which the cannabinoids have documented health benefits and growing pharmaceutical potential. Recent legal cannabis production in North America and Europe has been accompanied by an increase in reported findings for optimization of naturally occurring and synthetic cannabinoid production. Of the many environmental cues that can be manipulated during plant growth in controlled environments, cannabis cultivation with different lighting spectra indicates differential production and accumulation of medically important cannabinoids, including Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabigerol (CBG), as well as terpenes and flavonoids. Ultraviolet (UV) radiation shows potential in stimulating cannabinoid biosynthesis in cannabis trichomes and pre-harvest or post-harvest UV treatment merits further exploration to determine if plant secondary metabolite accumulation could be enhanced in this manner. Visible LED light can augment THC and terpene accumulation, but not CBD. Well-designed experiments with light wavelengths other than blue and red light will provide more insight into light-dependent regulatory and molecular pathways in cannabis. Lighting strategies such as subcanopy lighting and varied light spectra at different developmental stages can lower energy consumption and optimize cannabis PSM production. Although evidence demonstrates that secondary metabolites in cannabis may be modulated by the light spectrum like other plant species, several questions remain for cannabinoid production pathways in this fast-paced and growing industry. In summarizing recent research progress on light spectra and secondary metabolites in cannabis, along with pertinent light responses in model plant species, future research directions are presented.

Widely assumed phenotypic associations in Cannabis sativa lack a shared genetic basis

The flowering plant Cannabis sativa, cultivated for centuries for multiple purposes, displays extensive variation in phenotypic traits in addition to its wide array of secondary metabolite production. Notably, Cannabis produces two well-known secondary-metabolite cannabinoids: cannabidiolic acid (CBDA) and delta-9-tetrahydrocannabinolic acid (THCA), which are the main products sought by consumers in the medical and recreational market. Cannabis has several suggested subspecies which have been shown to differ in chemistry, branching patterns, leaf morphology and other traits. In this study we obtained measurements related to phytochemistry, reproductive traits, growth architecture, and leaf morphology from 297 hybrid individuals from a cross between two diverse lineages. We explored correlations among these characteristics to inform our understanding of which traits may be causally associated. Many of the traits widely assumed to be strongly correlated did not show any relationship in this hybrid population. The current taxonomy and legal regulation within Cannabis is based on phenotypic and chemical characteristics. However, we find these traits are not associated when lineages are inter-crossed, which is a common breeding practice and forms the basis of most modern marijuana and hemp germplasms. Our results suggest naming conventions based on leaf morphology do not correspond to the chemical properties in plants with hybrid ancestry. Therefore, a new system for identifying variation within Cannabis is warranted that will provide reliable identifiers of the properties important for recreational and, especially, medical use.

Cannabis use and sleep: Expectations, outcomes, and the role of age

STUDY OBJECTIVES

Determine relationship between cannabis use with 1) expectations of cannabis being a sleep aid, 2) subjective sleep outcomes, and 3) the influence of age on these relationships.

METHODS

In 152 moderate cannabis users with a wide age range (67% female, mean age = 31.45, SD = 12.96, age range = 21-70; mean days of cannabis use in prior two weeks = 5.54, SD = 5.25) we examined the influence of cannabis use history and behaviors on expectations of cannabis being a sleep aid and sleep outcomes via the Pittsburgh Sleep Quality Index (PSQI). Moderation analysis examined the role of age in the relationship between cannabis use and sleep outcomes.

RESULTS

Endorsing current cannabis use and more days of cannabis use were associated with increased expectations that cannabis use improves sleep (all β > 0.03, p < 0.04). Frequency of recent use and reported average THC or CBD concentration were largely not associated with sleep outcomes. However, endorsing current cannabis use was associated with worse subjective sleep quality (β = 1.34, p = 0.02) and increased frequency of consuming edibles was associated with worse subjective sleep efficiency (β = 0.03, p = 0.04), lower sleep duration (β = 0.03, p = 0.01), and higher global PSQI scores (worse overall sleep) (β = 0.10, p = 0.01). Additionally, age had a moderating influence on the relationship between increased self-reported concentration of CBD and both better sleep duration and sleep quality (both p < 0.03). While the main effects of cannabis use on sleep outcomes did not survive multiple comparisons correction test (all p adj > 0.34), the adjusted p values for the main effects of cannabis behaviors/history on expectations of cannabis as a sleep aid (p adj = 0.07-0.09) and the main effects of CBD concentration on sleep duration (p adj = 0.08), as well as the interaction terms of CBD and age for that model (p adj = 0.07), were trending.

CONCLUSION

Cannabis users have increased expectations of cannabis being a sleep aid, but few associations existed between cannabis use and sleep outcomes. The two exceptions were endorsing any cannabis use and frequency of edible use. Additionally, age may be an important moderator of the potential positive influence CBD concentration can have on sleep.

Development of Gas-Chromatographic Method for Simultaneous Determination of Cannabinoids and Terpenes in Hemp

An original gas chromatographic method has been developed for simultaneous determination of major terpenes and cannabinoids in plant samples and their extracts. The main issues to be addressed were the large differences in polarity and volatility between both groups of analytes, but also the need for an exhaustive decarboxylation of cannabinoid acidic forms. Sample preparation was minimised, also by avoiding any analyte derivatisation. Acetone was found to be the most appropriate extraction solvent. Successful chromatographic separation was achieved by using a medium polarity column. Limits of detection ranged from 120 to 260 ng/mL for terpenes and from 660 to 860 ng/mL for cannabinoids. Parallel testing proved the results for cannabinoids are comparable to those obtained from established HPLC methods. Despite very large differences in concentrations between both analyte groups, a linear range between 1 and 100 µg/mL for terpenes and between 10 and 1500 µg/mL for cannabinoids was determined.

Use of medical marijuana in cystic fibrosis patients

BACKGROUND

The usage and attitudes towards medical marijuana in Cystic Fibrosis (CF) patients is unknown. Through the use of a survey we aim to clarify rates and reasons for use.

METHODS

An anonymous survey was sent out to six centers in the Mid-Atlantic region of the United States. Use of and reason for medical marijuana was assessed, along with attitudes of the perceived utility of medical marijuana.

RESULTS

A total of 637 surveys were sent out, and 193 surveys were returned (30.3% return rate). Three did not give consent, and one was empty, for a total of 189 completed surveys. 31 subjects (16.5%) reported having used marijuana for medical purposes in their lifetime, with 29 (15.4%) of these in the past year. The most used forms were edible and vaporized. The most common indications for usage were pain and stress. 28 out of 31 found marijuana to be a great deal effective for their symptoms. 21 of the 31 rated marijuana very important or important to their health. There were two reported side effects, both mild. Of 156 subjects who responded to the question if they would be interested in medical marijuana if available, 72 (46.2%) replied yes.

CONCLUSION

The use of marijuana for medical reasons was 15.4% in the past year in this sample CF population, although more expressed interest if it was available through prescription. Side effects were rare. CF physicians are going to have to familiarize themselves with advantages and disadvantages of medical marijuana as there is a great deal of interest within the community, and legalization becomes more common.

Cannabis, Cannabinoids, and Brain Morphology: A Review of the Evidence

Cannabis and cannabinoid-based products are increasingly being accepted and commodified globally. Yet there is currently limited understanding of the effect of the varied cannabinoid compounds on the brain. Exogenous cannabinoids interact with the endogenous cannabinoid system that underpins vital functions in the brain and body, and they are thought to perturb key brain and cognitive function. However, much neuroimaging research has been confined to observational studies of cannabis users, without examining the specific role of the various cannabinoids (Δ⁹-tetrahydrocannabinol, cannabidiol, etc.). This review summarizes the brain structural imaging evidence to date associated with cannabis use, its major cannabinoids (e.g., Δ⁹-tetrahydrocannabinol, cannabidiol), and synthetic cannabinoid products that have emerged as recreational drugs. In doing so, we seek to highlight some of the key issues to consider in understanding cannabinoid-related brain effects, emphasizing the dual neurotoxic and neuroprotective role of cannabinoids, and the need to consider the distinct role of the varied cannabinoids in establishing their effect on the brain.