The 'entourage effect' or 'hodge-podge hashish': the questionable rebranding, marketing, and expectations of cannabis polypharmacy

Vaporized D-limonene selectively mitigates the acute anxiogenic effects of Δ9-tetrahydrocannabinol in healthy adults who intermittently use cannabis

BACKGROUND

Cannabis contains hundreds of chemical constituents beyond delta-9-tetrahydrocannabinol (THC), which is believed to drive most of its acute pharmacodynamic effects. The entourage effect theory asserts that non-THC constituents can impact acute cannabis effects, but few empirical studies have systematically evaluated this theory in humans. This study assessed whether the cannabis terpenoid d-limonene mitigates the acute anxiogenic effects of THC.

METHODS

Twenty healthy adults completed nine, double-blind outpatient sessions in which they inhaled vaporized THC alone (15mg or 30mg), d-limonene alone (1mg or 5mg), the same doses of THC and d-limonene together, or placebo; a subset of participants (n=12) completed a tenth session in which 30mg THC+15mg d-limonene was administered. Outcomes included subjective drug effects, cognitive/psychomotor performance, vital signs, and plasma THC and d-limonene concentrations.

RESULTS

When d-limonene was administered alone, pharmacodynamic outcomes did not differ from placebo. Administration of 15mg and 30mg THC alone produced subjective, cognitive, and physiological effects typical of acute cannabis exposure. Ratings of anxiety-like subjective effects qualitatively decreased as d-limonene dose increased and concurrent administration of 30mg THC+15mg d-limonene significantly reduced ratings of "anxious/nervous" and "paranoid" compared with 30mg THC alone. Other pharmacodynamic effects were unchanged by d-limonene. D-limonene plasma concentrations were dose orderly, and concurrent administration of d-limonene did not alter THC pharmacokinetics.

CONCLUSIONS

D-limonene selectively attenuated THC-induced anxiogenic effects, suggesting this terpenoid could increase the therapeutic index of THC. Future research should determine whether this effect extends to oral dose formulations and evaluate the interactions between other cannabis terpenoids or cannabinoids and THC.

The Neurotherapeutic Arsenal in Cannabis sativa: Insights into Anti-Neuroinflammatory and Neuroprotective Activity and Potential Entourage Effects

Cannabis, renowned for its historical medicinal use, harbours various bioactive compounds-cannabinoids, terpenes, and flavonoids. While major cannabinoids like delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have received extensive scrutiny for their pharmacological properties, emerging evidence underscores the collaborative interactions among these constituents, suggesting a collective therapeutic potential. This comprehensive review explores the intricate relationships and synergies between cannabinoids, terpenes, and flavonoids in cannabis. Cannabinoids, pivotal in cannabis's bioactivity, exhibit well-documented analgesic, anti-inflammatory, and neuroprotective effects. Terpenes, aromatic compounds imbuing distinct flavours, not only contribute to cannabis's sensory profile but also modulate cannabinoid effects through diverse molecular mechanisms. Flavonoids, another cannabis component, demonstrate anti-inflammatory, antioxidant, and neuroprotective properties, particularly relevant to neuroinflammation. The entourage hypothesis posits that combined cannabinoid, terpene, and flavonoid action yields synergistic or additive effects, surpassing individual compound efficacy. Recognizing the nuanced interactions is crucial for unravelling cannabis's complete therapeutic potential. Tailoring treatments based on the holistic composition of cannabis strains allows optimization of therapeutic outcomes while minimizing potential side effects. This review underscores the imperative to delve into the intricate roles of cannabinoids, terpenes, and flavonoids, offering promising prospects for innovative therapeutic interventions and advocating continued research to unlock cannabis's full therapeutic potential within the realm of natural plant-based medicine.

An observational study of clinical outcome measures in patients treated with cannabis-based medicinal products on the UK Medical Cannabis Registry

INTRODUCTION

While there is increasing evidence of the effects of cannabis-based medicinal products (CBMPs) on health-related quality of life (HRQoL), a major limitation of the current literature is the heterogeneity of studied CBMPs. This study aims to analyze changes in HRQoL in patients prescribed a homogenous selection of CBMPs.

METHODS

Primary outcomes were changes in patient-reported outcomes (PROMs) at 1, 3, 6, and 12 months from baseline. The secondary outcome was an adverse events analysis. Statistical significance was defined as p < 0.050.

RESULTS

1378 patients prescribed Adven® CBMPs (Curaleaf International, Guernsey, UK) were included in the final analysis. 581 (42.16%) participants were current users of cannabis at baseline. 641 (46.51%), 235 (17.05%), and 502 (36.43%) patients were treated with oils, dried flowers, or a combination of the two, respectively. Improvements were found in all PROMs in each route of administration at 1, 3, 6, and 12 months from baseline (p < 0.010). Those prescribed dried flower only or both oils and dried flower experienced greater improvements in GAD-7, SQS, and EQ-5D-5L index values at 12 months (p < 0.050). There was no difference in outcomes between those prescribed dried flower only or dried flower with oils (p > 0.050). 3663 (265.82%) adverse events were reported by 297 (21.55%) patients.

CONCLUSION

There was an associated improvement in self-reported anxiety, sleep quality, and HRQoL in patients treated with the CBMPs. Those prescribed treatment formulations including dried flower were most likely to show a clinical improvement. However, these results must be interpreted with caution given the limitations of study design.

Decoding the Postulated Entourage Effect of Medicinal Cannabis: What It Is and What It Isn't

The 'entourage effect' term was originally coined in a pre-clinical study observing endogenous bio-inactive metabolites potentiating the activity of a bioactive endocannabinoid. As a hypothetical afterthought, this was proposed to hold general relevance to the usage of products based on Cannabis sativa L. The term was later juxtaposed to polypharmacy pertaining to full-spectrum medicinal Cannabis products exerting an overall higher effect than the single compounds. Since the emergence of the term, a discussion of its pharmacological foundation and relevance has been ongoing. Advocates suggest that the 'entourage effect' is the reason many patients experience an overall better effect from full-spectrum products. Critics state that the term is unfounded and used primarily for marketing purposes in the Cannabis industry. This scoping review aims to segregate the primary research claiming as well as disputing the existence of the 'entourage effect' from a pharmacological perspective. The literature on this topic is in its infancy. Existing pre-clinical and clinical studies are in general based on simplistic methodologies and show contradictory findings, with the clinical data mostly relying on anecdotal and real-world evidence. We propose that the 'entourage effect' is explained by traditional pharmacological terms pertaining to other plant-based medicinal products and polypharmacy in general (e.g., synergistic interactions and bioenhancement).

Does the "Entourage Effect" in Cannabinoids Exist? A Narrative Scoping Review

Background: The concept of an "entourage" effect in the cannabis and cannabinoids' field was first introduced in the late 1990s, during a period when most research on medical cannabinoids focused on the effects of isolated cannabinoids, such as cannabidiol and Δ9-tetrahydrocannabinol. Over the past decade, however, with the increased understanding of the endocannabinoid system, the discovery of other phytocannabinoids and their potential therapeutic uses, the term has gained widespread use in scientific reviews and marketing campaigns. Objective: Critically review the application of the term "entourage effect (EE)" in the literature and its endorsement by certain sectors of the cannabis market. Also, explore the perspectives for further interpretation and elaboration of the term based on current evidence, aiming to contribute to a more nuanced understanding of the concept and its implications for cannabinoid-based medicine. Methods: A comprehensive review of the literature was conducted to evaluate the current state of knowledge regarding the entourage effect. Relevant studies and scientific reviews were analyzed to assess the evidence of clinical efficacy and safety, as well as the regulation of cannabinoid-containing product production. Results: The EE is now recognized as a synergistic phenomenon in which multiple components of cannabis interact to modulate the therapeutic actions of the plant. However, the literature provides limited evidence to support it as a stable and predictable phenomenon. Hence, there is also limited evidence to support clinical efficacy, safety, and appropriate regulation for cannabinoid-containing products based on a "entourage" hypothesis. Conclusion: The EE has significant implications for the medical use of cannabinoid-containing products and their prescription. Nevertheless, a critical evaluation of the term's application is necessary. Further research and evidence are needed to establish the clinical efficacy, safety, and regulatory framework for these products. It's crucial that regulators, the pharmaceutical industry, the media, and health care providers exercise caution and avoid prematurely promoting the entourage effect hypothesis as a scientific proven phenomenon for cannabinoids and other cannabis-derived compound combinations.

Comparative Pharmacokinetics of Commercially Available Cannabidiol Isolate, Broad-Spectrum, and Full-Spectrum Products

BACKGROUND AND OBJECTIVES

A wide variety of products containing cannabidiol (CBD) are available on the commercial market. One of the most common products, CBD oil, is administered to self-treat a variety of conditions. These oils are available as CBD isolate, broad-spectrum [all terpenes and minor cannabinoids except Δ-9-tetrahydrocannabinol (THC)], or full-spectrum (all terpenes and minor cannabinoids with THC < 0.3% dried weight) products. A systematic pharmacokinetic study was performed to determine whether there are differences in the pharmacokinetic parameters and systemic exposure of CBD after oral dosing as an isolate, broad-spectrum, or full-spectrum product.

METHODS

Male and female Sprague Dawley rats were treated with a single, equivalent oral dose of CBD delivered as isolate, broad-spectrum, or full-spectrum product. An additional study using an in-house preparation of CBD isolate plus 0.2% THC was performed. A permeability assay was also conducted to investigate whether the presence of THC alters the intestinal permeability of CBD.

RESULTS

There was an increase in the oral bioavailability of CBD (12% and 21% in male and female rats, respectively) when administered as a full-spectrum product compared with the isolate and broad-spectrum products. There was no difference in the bioavailability of CBD between the commercially available full-spectrum formulation (3.1% CBD; containing 0.2% THC plus terpenes and other minor cannabinoids) versus the in-house preparation of CBD full-spectrum (CBD isolate 3.2% plus 0.2% THC isolate). In vitro permeability assays demonstrated that the presence of THC increases permeability of CBD while also decreasing efflux through the gut wall.

CONCLUSIONS

The presence of 0.2% THC increased the oral bioavailability of CBD in male and female rats, indicating that full-spectrum products may produce increased effectiveness of CBD due to a greater exposure available systemically.

SELECTED CANNABIS TERPENES SYNERGIZE WITH THC TO PRODUCE INCREASED CB1 RECEPTOR ACTIVATION

The cannabis plant exerts its pharmaceutical activity primarily by the binding of cannabinoids to two G protein-coupled cannabinoid receptors, CB1 and CB2. The role that cannabis terpenes play in this activation has been considered and debated repeatedly, based on only limited experimental results. In the current study we used a controlled in-vitro heterologous expression system to quantify the activation of CB1 receptors by sixteen cannabis terpenes individually, by tetrahydrocannabinol (THC) alone and by THC-terpenes mixtures. The results demonstrate that all terpenes, when tested individually, activate CB1 receptors, at about 10-50% of the activation by THC alone. The combination of some of these terpenes with THC significantly increases the activity of the CB1 receptor, compared to THC alone. In some cases, several fold. Importantly, this amplification is evident at terpene to THC ratios similar to those in the cannabis plant, which reflect very low terpene concentrations. For some terpenes, the activation obtained by THC- terpene mixtures is notably greater than the sum of the activations by the individual components, suggesting a synergistic effect. Our results strongly support a modulatory effect of some of the terpenes on the interaction between THC and the CB1 receptor. As the most effective terpenes are not necessarily the most abundant ones in the cannabis plant, reaching "whole plant" or "full spectrum" composition is not necessarily an advantage. For enhanced therapeutic effects, desired compositions are attainable by enriching extracts with selected terpenes. These compositions adjust the treatment for various desired medicinal and personal needs.

Phase IIb Randomized, Placebo-Controlled, Dose-Escalating, Double-Blind Study of Cannabidiol Oil for the Relief of Symptoms in Advanced Cancer (MedCan1-CBD)

PURPOSE

To determine whether cannabidiol (CBD) oil can improve symptom distress in patients with advanced cancer receiving palliative care.

METHODS

Participants were adults with advanced cancer and symptom distress (Edmonton Symptom Assessment Scale [ESAS] total score of ≥ 10/90) who received titrated CBD oil 100 mg/mL, 0.5 mL once daily to 2 mL three times a day, or matched placebo for 28 days. The primary outcome was ESAS total symptom distress score (TSDS) at day 14. Response was defined as a decrease in TSDS by ≥ 6 at day 14. Secondary outcomes were ESAS TSDS over time, individual symptom scores, patient-determined effective dose, opioid use, Global Impression of Change, depression, anxiety, quality of life, and adverse events.

RESULTS

Of the 144 patients randomly assigned, the planned sample size of 58 participants on CBD and 63 on placebo reached the primary analysis point (day 14). The unadjusted change in TSDS from baseline to day 14 was -6.2 (standard deviation, 14.5) for placebo and -3.0 (standard deviation, 15.2) for CBD with no significant difference between arms (P = .24). Similarly, there was no detected difference in proportion of responders (placebo: 37 of 63 [58.7%], CBD: 26 of 58 [44.8%], P = .13). All components of ESAS improved (fell) over time with no difference between arms. The median dose of participant-selected CBD was 400 mg per day with no correlation with opioid dose. There was no detectable effect of CBD on quality of life, depression, or anxiety. Adverse events did not differ significantly between arms apart from dyspnea that was more common with CBD. Most participants reported feeling better or much better at days 14 (53% CBD and 65% placebo) and 28 (70% CBD and 64% placebo).

CONCLUSION

CBD oil did not add value to the reduction in symptom distress provided by specialist palliative care alone.

Secondary Terpenes in Cannabis sativa L.: Synthesis and Synergy

Cannabis is a complex biosynthetic plant, with a long history of medicinal use. While cannabinoids have received the majority of the attention for their psychoactive and pharmacological activities, cannabis produces a diverse array of phytochemicals, such as terpenes. These compounds are known to play a role in the aroma and flavor of cannabis but are potent biologically active molecules that exert effects on infectious as well as chronic diseases. Furthermore, terpenes have the potential to play important roles, such as synergistic and/or entourage compounds that modulate the activity of the cannabinoids. This review highlights the diversity and bioactivities of terpenes in cannabis, especially minor or secondary terpenes that are less concentrated in cannabis on a by-mass basis. We also explore the question of the entourage effect in cannabis, which studies to date have supported or refuted the concept of synergy in cannabis, and where synergy experimentation is headed, to better understand the interplay between phytochemicals within Cannabis sativa L.

Identification of minimum essential therapeutic mixtures from cannabis plant extracts by screening in cell and animal models of Parkinson’s disease

Medicinal cannabis has shown promise for the symptomatic treatment of Parkinson’s disease (PD), but patient exposure to whole plant mixtures may be undesirable due to concerns around safety, consistency, regulatory issues, and psychoactivity. Identification of a subset of components responsible for the potential therapeutic effects within cannabis represents a direct path forward for the generation of anti-PD drugs. Using an in silico database, literature reviews, and cell based assays, GB Sciences previously identified and patented a subset of five cannabinoids and five terpenes that could potentially recapitulate the anti-PD attributes of cannabis. While this work represents a critical step towards harnessing the anti-PD capabilities of cannabis, polypharmaceutical drugs of this complexity may not be feasible as therapeutics. In this paper, we utilize a reductionist approach to identify minimal essential mixtures (MEMs) of these components that are amenable to pharmacological formulation. In the first phase, cell-based models revealed that the cannabinoids had the most significant positive effects on neuroprotection and dopamine secretion. We then evaluated the ability of combinations of these cannabinoids to ameliorate a 6-hydroxydopmamine (OHDA)-induced change in locomotion in larval zebrafish, which has become a well-established PD disease model. Equimolar mixtures that each contained three cannabinoids were able to significantly reverse the OHDA mediated changes in locomotion and other advanced metrics of behavior. Additional screening of sixty-three variations of the original cannabinoid mixtures identified five highly efficacious mixtures that outperformed the original equimolar cannabinoid MEMs and represent the most attractive candidates for therapeutic development. This work highlights the strength of the reductionist approach for the development of ratio-controlled, cannabis mixture-based therapeutics for the treatment of Parkinson’s disease.

C. elegans as a test system to study relevant compounds that contribute to the specific health-related effects of different cannabis varieties

Background

The medicinal effects of cannabis varieties on the market cannot be explained solely by the presence of the major cannabinoids Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). Evidence for putative entourage effects caused by other compounds present in cannabis is hard to obtain due to the subjective nature of patient experience data. Caenorhabditis elegans (C. elegans) is an objective test system to identify cannabis compounds involved in claimed health and entourage effects.

Methods

From a medicinal cannabis breeding program by MariPharm BV, the Netherlands a set of 12 varieties were selected both THC rich varieties as well as CBD rich varieties. A consecutive extraction process was applied resulting in a non-polar (cannabinoid-rich) and polar (cannabinoid-poor) extract of each variety. The test model C. elegans was exposed to these extracts in a broad set of bioassays for appetite control, body oscillation, motility, and nervous system function.

Results

Exposing C. elegans to extracts with a high concentration of cannabinoids (> 1 μg/mL) reduces the life span of C. elegans dramatically. Exposing the nematodes to the low-cannabinoid (< 0.005 μg/mL) polar extracts, however, resulted in significant effects with respect to appetite control, body oscillation, motility, and nervous system-related functions in a dose-dependent and variety-dependent manner.

Discussion

C. elegans is a small, transparent organism with a complete nervous system, behavior and is due to its genetic robustness and short life cycle highly suitable to unravel entourage effects of Cannabis compounds. Although C. elegans lacks an obvious CB1 and CB2 receptor it has orthologs of Serotonin and Vanilloid receptor which are also involved in (endo)cannabinoid signaling.

Conclusion

By using C. elegans, we were able to objectively distinguish different effects of different varieties despite the cannabinoid content. C. elegans seems a useful test system for studying entourage effects, for targeted medicinal cannabis breeding programs and product development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-022-00162-9.

A Critical Evaluation of Terpenoid Signaling at Cannabinoid CB1 Receptors in a Neuronal Model

In addition to phytocannabinoids, cannabis contains terpenoids that are claimed to have a myriad of effects on the body. We tested a panel of five common cannabis terpenoids, myrcene, linalool, limonene, α-pinene and nerolidol, in two neuronal models, autaptic hippocampal neurons and dorsal root ganglion (DRG) neurons. Autaptic neurons express a form of cannabinoid CB1 receptor-dependent retrograde plasticity while DRGs express a variety of transient receptor potential (TRP) channels. Most terpenoids had little or no effect on neuronal cannabinoid signaling. The exception was nerolidol, which inhibited endocannabinoid signaling. Notably, this is not via inhibition of CB1 receptors but by inhibiting some aspect of 2-arachidonoylglycerol (2-AG) production/delivery; the mechanism does not involve reducing the activity of the 2-AG-synthesizing diacylglycerol lipases (DAGLs). Nerolidol was also the only terpenoid that activated a sustained calcium response in a small (7%) subpopulation of DRGs. In summary, we found that only one of five terpenoids tested had notable effects on cannabinoid signaling in two neuronal models. Our results suggest that a few terpenoids may indeed interact with some components of the cannabinoid signaling system and may therefore offer interesting insights upon further study.

Patterns and correlates of cannabidiol product and marijuana co-use in a sample of U.S. young adults

OBJECTIVE

Cannabis-derived products containing cannabidiol with no or minimal levels of delta 9-tetrahydrocannabinol (CBD products) are widely available in the United States and use of these products is common among young adults and those who use marijuana. The purpose of this study was to examine patterns and correlates of CBD product use and co-use with marijuana in a sample of young adults.

METHOD

The study used cross-sectional survey data collected in 2019-2020 from a cohort of young adults (n = 2534; mean age 23) based primarily in California. The survey assessed lifetime, past-year, and past-month frequency and type of CBD products used, frequency and amount of marijuana consumption and indicators of marijuana use-related problems. Linear, Poisson, and logistic regression models compared individuals reporting past month CBD-only use, marijuana-only use, concurrent CBD + marijuana use (co-use), and use of neither product. Among those reporting co-use, we examined associations between CBD use frequency and marijuana use frequency and heaviness of use (occasions per day) and indicators of problem marijuana use (e.g., Cannabis Use Disorder Identification Test Short-Form, solitary use, marijuana consequences).

RESULTS

Approximately 13% of respondents endorsed past-month CBD use; of these, over three-quarters (79%) indicated past-month co-use of marijuana. Among individuals reporting co-use, more frequent CBD use was associated with more frequent and heavier marijuana use but was not associated with marijuana use-related problems.

CONCLUSIONS

CBD use was common and associated with higher levels of marijuana consumption in this sample. Routinely assessing CBD use may provide a more comprehensive understanding of individuals' cannabis product consumption.

Epilepsy and cannabis: so near, yet so far

Following media attention on children with refractory epilepsies reportedly deriving benefit from cannabis-based medicinal products (CBMPs), the UK government changed the law in 2018 so that CBMPs could be legally prescribed. Subsequently, a pure cannabidiol (CBD) product has been licensed for two epilepsy syndromes. However, despite pressure from campaign groups and allied politicians, almost no children have received unlicensed CBMPs under the UK NHS. This review explores the science behind CBMPs in paediatric epilepsies and highlights the areas that warrant further research. It identifies a lack of level I evidence for efficacy and safety as, currently, the major obstacle to prescribing. Unlicensed medicines are often used in paediatrics but almost all are used 'off-label', with supporting evidence of efficacy and safety derived either from other age-groups or from disease conditions. CBMPs, except for pure CBD, are unique in that they are currently both unlicensed and fall outside the 'off-label' category. The review acknowledges the treatment gap in refractory epilepsies and the potential use of CBMPs. However, it argues against exceptionally circumventing the usual standard of evidence required by regulatory prescribing authorities and warns against allowing vulnerable children to become the 'trojan horse' for deregulation of the commercial cannabis market.

The impact of extraction protocol on the chemical profile of cannabis extracts from a single cultivar

The last two decades have seen a dramatic shift in cannabis legislation around the world. Cannabis products are now widely available and commercial production and use of phytocannabinoid products is rapidly growing. However, this growth is outpacing the research needed to elucidate the therapeutic efficacy of the myriad of chemical compounds found primarily in the flower of the female cannabis plant. This lack of research and corresponding regulation has resulted in processing methods, products, and terminology that are variable and confusing for consumers. Importantly, the impact of processing methods on the resulting chemical profile of full spectrum cannabis extracts is not well understood. As a first step in addressing this knowledge gap we have utilized a combination of analytical approaches to characterize the broad chemical composition of a single cannabis cultivar that was processed using previously optimized and commonly used commercial extraction protocols including alcoholic solvents and super critical carbon dioxide. Significant variation in the bioactive chemical profile was observed in the extracts resulting from the different protocols demonstrating the need for further research regarding the influence of processing on therapeutic efficacy as well as the importance of labeling in the marketing of multi-component cannabis products.

Analgesic Potential of Terpenes Derived from Cannabis sativa

Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.

Topical Use of Cannabis sativa L. Biochemicals

Cannabis sativa L. plant is currently attracting increasing interest in cosmetics and dermatology. In this review, the biologically active compounds of hemp are discussed. Particularly the complex interactions of cannabinoids with the endocannabinoid system of the skin to treat various conditions (such as acne, allergic contact dermatitis, melanoma, and psoriasis) with clinical data. Moreover, the properties of some cannabinoids make them candidates as cosmetic actives for certain skin types. Hemp seed oil and its minor bioactive compounds such as terpenes, flavonoids, carotenoids, and phytosterols are also discussed for their added value in cosmetic formulation.

Cannabidiol treatment in hand osteoarthritis and psoriatic arthritis: a randomized, double-blind placebo-controlled trial

ABSTRACT

Cannabidiol (CBD) is increasingly used as analgesic medication even though the recent International Association for the Study of Pain presidential task force on cannabis and cannabinoid analgesia found a lack of trials examining CBD for pain management. The present trial examines CBD as add on analgesic therapy in patients with hand osteoarthritis or psoriatic arthritis experiencing moderate pain intensity despite therapy. Using a randomized double-blind, placebo-controlled design, patients received synthetic CBD 20-30mg or placebo daily for 12 weeks. Primary outcome was pain intensity during the last 24 hours (0-100mm); safety outcomes were percentage of patients experiencing adverse events and a characterization of serious adverse events. Explorative outcomes included change in Pittsburgh Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS) and Health Assessment Questionnaire (HAQ-DI).One hundred and thirty-six patients were randomized 129 were included in the primary analysis. Between group difference in pain intensity at 12 weeks was 0.23mm (95%CI -9.41 to 9.90; p = 0.96). 22% patients receiving CBD and 21% receiving placebo experienced a reduction in pain intensity of more than 30mm. We found neither clinically nor statistically significant effect of CBD for pain intensity in patients with hand osteoarthritis and psoriatic arthritis when compared to placebo. Additionally, no statistically significant effects were found on sleep quality, depression, anxiety, or pain catastrophizing scores.

Biosynthesis of Nature-Inspired Unnatural Cannabinoids

Natural products make up a large proportion of medicine available today. Cannabinoids from the plant Cannabis sativa is one unique class of meroterpenoids that have shown a wide range of bioactivities and recently seen significant developments in their status as therapeutic agents for various indications. Their complex chemical structures make it difficult to chemically synthesize them in efficient yields. Synthetic biology has presented a solution to this through metabolic engineering in heterologous hosts. Through genetic manipulation, rare phytocannabinoids that are produced in low yields in the plant can now be synthesized in larger quantities for therapeutic and commercial use. Additionally, an exciting avenue of exploring new chemical spaces is made available as novel derivatized compounds can be produced and investigated for their bioactivities. In this review, we summarized the biosynthetic pathways of phytocannabinoids and synthetic biology efforts in producing them in heterologous hosts. Detailed mechanistic insights are discussed in each part of the pathway in order to explore strategies for creating novel cannabinoids. Lastly, we discussed studies conducted on biological targets such as CB1, CB2 and orphan receptors along with their affinities to these cannabinoid ligands with a view to inform upstream diversification efforts.

Current controversies in medical cannabis: Recent developments in human clinical applications and potential therapeutics

Knowledge about the therapeutic potential of medical cannabis has greatly improved over the past decade, with an ever-increasing range of developments in human clinical applications. A growing body of scientific evidence supports the use of medical cannabis products for some therapeutic indications, whilst for others, the evidence base remains disputed. For this narrative review, we incorporate areas where the current evidence base is substantial, such as intractable childhood epilepsy and multiple sclerosis, as well as areas where the evidence is still controversial, such as PTSD and anxiety. We provide a high-level summary of current developments using findings from recent major reviews, as well as real world evidence (RWE), including global database registries and other patient reported outcomes (PROs). On the one hand, our strongest empirical data supports the use of cannabis-based medicinal products (CBMPs) for conditions with relatively small patient numbers. Yet on the other hand, the conditions, where the highest patient numbers present, often have debatable clinical evidence but good RWE, incorporating PROs of 1000s of patients. The discord between PROs and the respective strength of the evidence from randomised controlled trials (RCTs) highlights the urgent need for further research. The scientific literature examining the efficacy of medical cannabis for many conditions is still developing, whilst large numbers of patients globally have been successfully using medical cannabis to treat a broad range of conditions. We conclude on the importance of systematically developing RWE databases to supplement RCTs and to bridge the current evidence gaps.

Cannabis sativa terpenes are cannabimimetic and selectively enhance cannabinoid activity

Limited evidence has suggested that terpenes found in Cannabis sativa are analgesic, and could produce an "entourage effect" whereby they modulate cannabinoids to result in improved outcomes. However this hypothesis is controversial, with limited evidence. We thus investigated Cannabis sativa terpenes alone and with the cannabinoid agonist WIN55,212 using in vitro and in vivo approaches. We found that the terpenes α-humulene, geraniol, linalool, and β-pinene produced cannabinoid tetrad behaviors in mice, suggesting cannabimimetic activity. Some behaviors could be blocked by cannabinoid or adenosine receptor antagonists, suggesting a mixed mechanism of action. These behavioral effects were selectively additive with WIN55,212, suggesting terpenes can boost cannabinoid activity. In vitro experiments showed that all terpenes activated the CB1R, while some activated other targets. Our findings suggest that these Cannabis terpenes are multifunctional cannabimimetic ligands that provide conceptual support for the entourage effect hypothesis and could be used to enhance the therapeutic properties of cannabinoids.

Neural Stem Cells and Cannabinoids in the Spotlight as Potential Therapy for Epilepsy

Epilepsy is one of the most common brain diseases worldwide, having a huge burden in society. The main hallmark of epilepsy is the occurrence of spontaneous recurrent seizures, having a tremendous impact on the lives of the patients and of their relatives. Currently, the therapeutic strategies are mostly based on the use of antiepileptic drugs, and because several types of epilepsies are of unknown origin, a high percentage of patients are resistant to the available pharmacotherapy, continuing to experience seizures overtime. Therefore, the search for new drugs and therapeutic targets is highly important. One key aspect to be targeted is the aberrant adult hippocampal neurogenesis (AHN) derived from Neural Stem Cells (NSCs). Indeed, targeting seizure-induced AHN may reduce recurrent seizures and shed some light on the mechanisms of disease. The endocannabinoid system is a known modulator of AHN, and due to the known endogenous antiepileptic properties, it is an interesting candidate for the generation of new antiepileptic drugs. However, further studies and clinical trials are required to investigate the putative mechanisms by which cannabinoids can be used to treat epilepsy. In this manuscript, we will review how cannabinoid-induced modulation of NSCs may promote neural plasticity and whether these drugs can be used as putative antiepileptic treatment.

Lack of evidence for the effectiveness or safety of over-the-counter cannabidiol products

Over the past 5 years, public interest in the potential health benefits of cannabidiol (CBD) has increased exponentially, and a wide range of over-the-counter (OTC) preparations of CBD are now available. A substantial proportion of the population appears to have used these products, yet the extent to which they are effective or safe is unclear. We reviewed the evidence for whether CBD has significant pharmacological and symptomatic effects at the doses typically found in OTC preparations. We found that most of the evidence for beneficial effects is derived from studies of pure, pharmaceutical grade CBD at relatively high doses. Relatively few studies have examined the effect of OTC CBD preparations, or of CBD at low doses. Thus, at present, there is little evidence that OTC CBD products have health benefits, and their safety has not been investigated. Controlled trials of OTC and low-dose CBD preparations are needed to resolve these issues.

Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis

In recent years, and even more since its legalization in several jurisdictions, cannabis and the endocannabinoid system have received an increasing amount of interest related to their potential exploitation in clinical settings. Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.

Differentiating Full-Spectrum Hemp Extracts from CBD Isolates: Implications for Policy, Safety and Science

The passage of the 2018 United States Agriculture Improvement Act removed industrial hemp, defined as Cannabis sativa L. containing less than 0.3% THC content by dry weight, from Schedule I of the Controlled Substances Act and made it an agricultural commodity. Following these changes, the popularity of hemp-derived cannabidiol (CBD) dietary supplements by consumers has greatly exceeded the scientific understanding of purported benefits, safety and composition of these botanical extracts. Further complicating CBD hemp supplement regulation, Food and Drug Administration (FDA) considers CBD to be an approved drug (Epidiolex) in the treatment of severe epilepsy disorders, Dravet and Lennox-Gastaut syndromes. At the same time, hemp-derived CBD supplements can contain a complex phytochemical matrix from the hemp plant, distinguishing the composition of these products from isolated CBD preparations. This work aims to provide clarity on differentiating botanical full-spectrum hemp extracts containing CBD from isolates, from a phytochemical, toxicological and regulatory perspective.

Practical Considerations of Hypotheses and Evidence in Cannabis Pharmacotherapy: Refining Expectations of Clinical Endocannabinoid Deficiency

An Industry founded on the promotion of presumed health and wellness benefits of cannabis use continues to grow in the United States, despite the lack of substantial evidence in support of the many claims being made. Several hypotheses exist regarding the role of endocannabinoids in human health and the pertinence of phytocannabinoids as pharmacotherapies for addressing their dysregulation. An opinion is offered regarding the tenuous nature of these assumptions and questions are raised regarding how best to interpret the complex metabolic interplay of the still vaguely defined endocannabinoid system.