Cannabidiol is a negative allosteric modulator of the cannabinoid CB1 receptor

The impact of cannabis use on local anesthetic dosing during hair restoration surgery: a case report, proposed mechanisms, and clinical recommendations

Cannabis use has increased significantly in the last decade. This article presents a case where a patient needed more local anesthetic (LA) than usual to induce effective anesthesia during hair transplant surgery. The reason cannabis users often need more LA is poorly understood. One possibility is that cannabis withdrawal effect makes patients more sensitive to pain and stress. Additionally, vasodilatory property of cannabis may speed up LA clearance from the application site. The interactions of two major cannabinoids, cannabidiol (CBD) and tetrahydrocannabinol (THC), with cannabinoid receptor type 1 (CB1), cannabinoid receptor type 2 (CB2), and transient receptor potential vanilloid 1 (TRPV1) receptors are also complex. Furthermore, CBD and THC function as cytochrome P450 enzyme inhibitors potentially impacting systemic metabolism. When planning to administer LA during hair restoration surgery in cannabis users, clinicians should obtain a detailed history of prior consumption (type of cannabis, frequency, dosage). Preoperative planning should consider the anticipated duration of surgery and calculate the maximum safe LA dose to avoid the risk of toxicity. Also, patients should be carefully monitored for vital signs during surgery. If a patient requires frequent re-injection to remain pain free, the surgeon may need to re-assess the surgical plan to avoid toxicity.

Cannabidiol and cognition: a literature review of human randomized controlled trials

Cannabidiol (CBD) is a phytocannabinoid without intoxicating properties. While CBD can improve neurophysiological functions and subjective symptoms, its effect on cognitive function remains unclear. We summarized the available randomized controlled trials investigating CBD administration and cognitive function. A review of the literature was conducted using the following keywords on PubMed/Medline: (cannabis OR cannabidiol OR cannabinoid OR CBD OR Δ9-tetrahydrocannabinol OR tetrahydrocannabinol) AND (neurology OR brain OR psychiatric OR neuroscience OR psychology OR cognition) AND (human) AND (randomized controlled trial OR RCT). The search yielded 1038 articles with 36 total included for this literature review. The articles included healthy participants, neurological disease, psychiatric disease, psychosis, paranoia, schizophrenia, and drug-use disorders. Studies with healthy participants included a variety of dosing strategies, suggesting an effect on cognitive function and sleep quality. In Parkinson's disease, 75-300 mg CBD resulted in mild improvements in daily life activities. Decreases in subjective anxiety were found in patients with psychiatric disease using CBD doses ranging from 300 to 400 mg. In patients with psychosis and paranoia, 600 mg CBD showed inconsistent results in cognitive function. In patients with schizophrenia, up to 1000 mg CBD per day had minimal effects on cognition. Finally, up to 800 mg CBD had minimal effects on cognitive function in patients with substance use disorders. The findings are limited by utilization of acute dosing, variations in CBD dose, and different routes of administration. Standardized dosing and CBD formulations are needed to assess its efficacy for improving cognition.

Advances in cannabinoid receptors pharmacology: from receptor structural insights to ligand discovery

The medicinal and recreational uses of Cannabis sativa have been recognized for thousands of years. Today, cannabis-derived medicines are used to treat a variety of conditions, including chronic pain, epilepsy, multiple sclerosis, and chemotherapy-induced nausea. However, cannabis use disorder (CUD) has become the third most prevalent substance use disorder globally. Cannabinoid receptors are the primary targets that mediate the effects of cannabis and its analogs. Despite their importance, the mechanisms of modulation and the full therapeutic potential of cannabinoid receptors remain unclear, hindering the development of the next generation of cannabinoid-based drugs. This review summarizes the discovery and medicinal potential of phytocannabinoids and explores the distribution, signaling pathways, and functional roles of cannabinoid receptors. It also discusses classical cannabinoid drugs, as well as agonists, antagonists, and inverse agonists, which serve as key therapeutic agents. Recent advancements in the development of allosteric drugs are highlighted, with a focus on positive and negative allosteric modulators (PAMs and NAMs) that target CB1 and CB2 receptors. The identification of multiple allosteric sites on the CB1 receptor and the structural basis for allosteric modulation are emphasized, along with the structure-based discovery of ago-BAMs for CB1. This review concludes by examining the future potential of allosteric modulators in cannabinoid drug development, noting that ongoing progress in cannabinoid-derived drugs continues to open new avenues for therapeutic use and paves the way for future research into their full medicinal potential.

Cannabidiolic Acid Rescues Deficits in Hippocampal Long-Term Potentiation in Models of Alzheimer's Disease: An Electrophysiological and Proteomic Analysis

In this study, we have examined the neuroprotective effects of cannabidiolic acid (CBDA) in models of Alzheimer's disease (AD). We used in vitro electrophysiological recording in hippocampal slices and performed proteomic analysis of cortical tissue from APPswe/PS1dE9 (APP/PS1) mice. In wild-type (WT) slices from C57BL6 mice, acute treatment with CBDA (10 μM) did not alter levels of hippocampal long-term potentiation (LTP); however, it did reverse the attenuation of LTP produced by acute beta amyloid peptide (Aβ42). We also examined the effects of CBDA or vehicle in APP/PS1 mice and WT littermates over a 5-week period at 8 months. LTP levels recorded in slices from WT mice treated with CBDA at 1, 10, or 30 mg/kg (IP) or vehicle were similar. LTP was attenuated in slices from vehicle-treated APP/PS1 compared to vehicle-treated WT mice, while treatment of APP/PS1 mice with all doses of CBDA reversed the deficits in LTP. There was also a deficit in paired-pulse facilitation (PPF) in vehicle-treated APP/PS1 compared to WT, indicating altered synaptic function and transmitter release; this was reversed in slices from CBDA-treated APP/PS1 mice. Levels of cortical soluble Aβ42 were similar across CBDA- and vehicle-treated groups; however, the level of aggregated Aβ42 was decreased in the CBDA-treated group. Proteomic analysis of cortical tissue from APP/PS1 cortex compared to WT revealed alterations in protein expression, with pathway enrichment analyses suggesting implicated canonical pathways, including mitochondrial dysfunction, protein sorting, and synaptogenesis; all were significantly improved by CBDA treatment. These changes likely facilitate the improvement in synaptic transmission and LTP we observed following CBDA treatment in APP/PS1 mice. This research suggests that CBDA should be considered a novel therapy for AD.

Cannabidiol as a multifaceted therapeutic agent: mitigating Alzheimer's disease pathology and enhancing cognitive function

BACKGROUND

Cannabidiol (CBD), the second most abundant phytocannabinoid in Cannabis sativa, has garnered significant interest due to its non-psychoactive nature and diverse receptor interactions.

METHODS

This study employs in vitro and in vivo methodologies to validate CBD's potential as a treatment for Alzheimer's disease (AD) by addressing key hallmarks of the condition and promoting neuroprotective effects on spatial memory.

RESULTS

Our findings demonstrate CBD's ability to decrease pTau and Aβ aggregation and to mitigate their axonal transport between cortical and hippocampal neurons. Moreover, CBD treatment was shown to reduce neuroinflammation, as CBD was able to skew microglia towards a neuroprotective M2 phenotype while attenuating proinflammatory cytokine release in the 5xFAD AD mouse model. Notably, daily CBD injections (10 mg/Kg) for 28 days in 5xFAD mice resulted in significant improvements in both short- and long-term spatial memory. The study also reveals CBD's capacity to partially revert neurite formation loss induced by Aβ, Tau, and pTau proteins, suggesting a potential role in promoting neuronal plasticity. Additionally, CBD treatment led to a reduction in reactive oxygen species (ROS) formation and increased neuronal viability in the presence of AD-associated protein aggregates.

CONCLUSIONS

These multifaceted effects of CBD, ranging from molecular-level modulation to behavioral improvements, underscore its potential as a comprehensive therapeutic approach for AD. The findings not only support CBD's neuroprotective properties but also highlight its ability to target multiple pathological processes simultaneously, offering a promising avenue for future AD treatment strategies.

Profiling Allosteric Modulators of CB1R with an Allosteric Fluoroprobe

Allosteric modulation of cannabinoid receptor type 1 (CB1R) offers a promising alternative to conventional therapeutic approaches using orthosteric ligands (OLs). Currently, CB1R allosteric modulators (AMs) are characterized based on their ability to modulate binding or functional response of OLs, preventing isolation of individual contributions by allosteric and orthosteric ligands. Herein, we develop the first allosteric fluoroprobe and attendant FRET-based assay allowing for the direct profiling of CB1R AMs without coincubation with an OL. Our allosteric tracer enables differentiation of allosteric and orthosteric ligands as well as their pharmacological profiling at CB1R. The utility of this work is highlighted by addressing ambiguities surrounding the binding of cannabidiol (CBD). CBD was found to interact with both allosteric and orthosteric sites of CB1R with comparable affinity (pKi=5.34 and 5.67, respectively).

Beyond the hype: a comprehensive exploration of CBD's biological impacts and mechanisms of action

BACKGROUND

Cannabidiol (CBD) is the primary non-psychoactive component of cannabis. Consumption of CBD is increasing rapidly as it is federally legal and widely available in the United States, Europe, Mexico, Canada, and Asia. CBD is gaining traction in medical and biochemical research, though a comprehensive classification of CBD receptor interactions is yet to be elucidated.

METHODS

A comprehensive literature search across PubMed, Web of Science, and Google Scholar identified studies reporting cannabidiol (CBD) interactions with receptors, enzymes, and biological processes. Eligible articles included cell culture, animal model, biochemical, and clinical studies. Findings were thematically synthesized by body system, emphasizing mechanisms and implications for health and disease.

RESULTS

Herein, I compile the literature to date of known interactions between CBD and various receptors, enzymes, and processes. I discuss the impact of CBD exposure on multiple processes, including endocannabinoid receptors, ion channels, cytochrome 450 enzymes, inflammatory pathways, and sex hormone regulation. I explain the potential effects of CBD on psychiatric disorders, seizure activity, nausea and vomiting, pain sensation, thermal regulation, neuronal signaling, neurodegenerative diseases, reproductive aging, drug metabolism, inflammation, sex hormone regulation, and energy homeostasis.

CONCLUSIONS

Understanding how CBD functions and how it can interact with other recreational or pharmaceutical medications is necessary for proper clinical management of patients who consume CBD.

Effects of cannabidiol (CBD) treatment on age-related cognitive decline in C57 mice

Aging is associated with cognitive decline, and currently, there are no approved medications that can prevent these impairments. Recently, cannabinoids derived from Cannabis sativa have emerged as promising therapeutic compounds with neuroprotective, anti-inflammatory, and cognitive-enhancing properties. Despite their benefits, further research is needed to fully understand their efficacy across various conditions. This study investigates the effects of cannabidiol (CBD) on memory impairment and brain inflammation in aging mice. Fourteen-month-old C57 mice were administered CBD orally for 7 months and subsequently evaluated between 19 and 21 months of age using behavioral tasks that are sensitive to dysfunction of the perirhinal cortex, hippocampus, amygdala, and various brain regions that are crucial for motor control and coordination. The findings of this study indicate that CBD reduces inflammatory response in the brain and improves cognitive decline associated with aging.

Crosstalk Between Signaling Stroke Cascade and Therapeutic Receptors PPAR-γ, ROCK, CB1R, and CB2R: From Mechanism to Therapies

Stroke remains a leading cause of disability and mortality worldwide, primarily due to the complex and multifaceted nature of its pathophysiology. This review aims to provide a comprehensive and mechanistic understanding of the crosstalk between key signaling pathways activated during stroke and the therapeutic potential of specific receptors: PPAR-γ, ROCK, CB1R, and CB2R. We delve into the intricate signaling cascades that occur post-stroke, including excitotoxicity, oxidative stress, and inflammation, highlighting the pivotal molecular players involved. PPAR-γ, known for its neuroprotective and anti-inflammatory properties, emerges as a critical modulator in stroke therapy. ROCK, a central component in the Rho/ROCK pathway, is implicated in vascular and neuronal damage, making its inhibition a promising therapeutic strategy. The roles of CB1R and CB2R within the endocannabinoid system are explored, with a focus on their dualistic nature in neuroprotection and neurotoxicity. The review further examines the interconnectivity of these receptors within the stroke signaling network, proposing that their synergistic modulation could enhance therapeutic outcomes. Current therapeutic approaches, including pharmacological and multi-target strategies, are critically evaluated, addressing the challenges in translating mechanistic insights into clinical practice. Additionally, the identification and utilization of biomarkers for stroke diagnosis and therapy monitoring are discussed, offering a glimpse into future prospects. Emerging therapies, novel drug developments, and personalized medicine approaches are presented as potential game-changers in stroke treatment.

UK medical cannabis registry: an updated clinical outcomes analysis of patients with post-traumatic stress disorder

BACKGROUND

Cannabis-based medicinal products (CBMPs) are a potential treatment for post-traumatic stress disorder (PTSD), but their long-term efficacy and safety need further investigation. This study assessed the changes in health-related quality of life (HRQoL) and adverse events in PTSD patients prescribed CBMPs.

RESEARCH DESIGN AND METHODS

This observational cohort study included PTSD patients enrolled on the UK Medical Cannabis Registry for 18 months or longer. Changes in PTSD-specific symptoms (IES-R), anxiety (GAD-7), sleep quality (SQS), and general HRQoL (EQ-5D-5 L) were assessed at 1, 3, 6, 12, and 18 months.

RESULTS

In 269 patients, significant improvements in PTSD symptoms, anxiety, sleep quality, and HRQoL were observed at all follow-up points (p < 0.001). On multivariate logistic regression, male gender (OR = 0.51; 95% CI:0.28-0.94; p = 0.034) was associated with a reduced chance of reporting improvements in IES-R. Adverse events were reported by 70 (26.02%) patients, with insomnia (n = 42, 15.61%) and fatigue (n = 40, 14.87%) being the most common.

CONCLUSIONS

CBMPs were associated with improvements in PTSD symptoms, anxiety, sleep, and HRQoL at up to 18 months. Although the study's observational nature limits causal conclusions, these findings support further assessment of medical cannabis.

TRIAL REGISTRATION

This is an observational study and is not registered as a clinical trial.

Cannabidiol oil delays pancreatic islet dysfunction in Wistar rats under hypercaloric diet

Hypercaloric diet (HCD) intake can lead to metabolic alterations, such as metabolic syndrome and type-2 diabetes mellitus. Phytocannabinoid cannabidiol (CBD) is a GPR55 receptor antagonist involved in insulin secretion and other functions in pancreatic islet. The therapeutic use of CBD has been suggested for diabetes, but little is known regarding its effects on pancreatic islet physiology. Our aim was to evaluate the effects of CBD oil on pancreatic islets, from Wistar rats under HCD. Male rats were divided in 4 groups: Normal diet vehicle-treated (control) and CBD-treated group. Rats under HCD were subdivided in treated with vehicle (HCD) and with CBD oil administered 21 mg/Kg orally, 0.5 ml in 3 days per week; controls received coconut oil as vehicle. Body weight, food intake, and water consumption were recorded. After 20 weeks, glucose tolerance curve was performed; serum insulin was determined by ELISA, and pancreas was removed for histological and gene expression analysis for insulin, glucagon, PDX-1, MafA and GPR55 receptor. CBD treatment reduced body weight and food intake but increased fluid consumption, independently of diets. In control group, CBD did not alter blood glucose and serum insulin, but modified expression for GPR55 receptor, glucagon, insulin and MafA. Rats under HCD and treated with CBD decreased glycaemia, insulinaemia, islets relative area, GPR55-positive cells, PDX-1 and MafA gene expression, meanwhile insulin and glucagon expression was increased. In conclusion, CBD ameliorated HCD effects through changes in insulin, glucagon and GPR55 receptor expressions. We assume CBD interacts with other receptors beside GPR55.

Development of Squaramides as Allosteric Modulators of the CB1 Receptor: Synthesis, Computational Studies, Biological Characterization, and Effects against Cocaine-Induced Behavioral Sensitization and Reinstatement in Rats

Cannabinoid receptor type 1 (CB1) negative allosteric modulators have emerged as an alternate approach to CB1 orthosteric antagonists/inverse agonists for cocaine addiction treatment. This study explores aryl-alkyl squaramides as CB1 allosteric modulators, featuring RTICBM-262 (3) with good in vitro potencies in CB1 calcium mobilization, [35S]GTPγS binding, and cAMP assays. Molecular modeling studies suggest 3 bound in a similar pocket as Org27569, forming π-stacking with key residues H1542.41 and W2414.50, and the potential C98-C107 disulfide bond had limited impact on its binding or receptor activation. ADME and in vivo pharmacokinetic studies suggest that 3 had reasonable metabolic stability, brain penetration, and selectivity against a panel of ∼ 50 targets but poor solubility and high protein binding. At 5.6 mg/kg (i.p.), 3 significantly attenuated both cocaine-seeking behavior specific to cue-induced reinstatement and cocaine-induced behavioral sensitization without altering locomotor activity. These results support squaramides as promising candidates for further investigation for cocaine addiction treatment.

Considering Long-Acting Synthetic Cannabidiol for Chronic Pain: A Narrative Review

Chronic pain is prevalent and challenging to treat. Cannabinoids, in particular cannabidiol (CBD), have been evaluated as analgesics without the issues of tolerance or dependence. Side effects tend to be mild and infrequent. These products have multiple routes of administration and composition, and some are available over the counter, allowing pain patients to self-medicate. Most self-medicated CBD are plant-derived extracts administered as either oils, pills, or by inhalation. During the early 1960s, CBD was chemically synthesized for the first time, but it was not yet approved for medical use; synthetic CBD has been and continues to be studied in clinical trials for numerous indications, including chronic pain, neuropathic pain, and pain in cancer. However, studies are often small, populations heterogeneous, and some results are equivocal. Research is lively, with over 60 studies reported on ClinicalTrials.gov. Multimodal CBD therapy may hold promise, particularly in combination with palmitoylethanolamide. Greater patient education and training for physicians and other healthcare providers are needed along with more comprehensive studies. Considering the problem of chronic pain, further intensive study of synthetic CBD for pain control is warranted to meet this unmet clinical need. This is particularly important in the context of long-lasting administration methods that enable easy dosing and support long-term use for patients dealing with persistent and often debilitating symptoms.

Cannabidiol reverses myeloperoxidase hyperactivity in the prefrontal cortex and striatum, and reduces protein carbonyls in the hippocampus in a ketamine-induced schizophrenia rat model

BACKGROUND

Schizophrenia (SCZ) has limited treatment options, often with significant side effects. Cannabidiol (CBD), a non-euphoric phytocannabinoid, has shown potential as a novel therapeutic option in SCZ due to antipsychotic-like, anti-inflammatory, and antioxidant properties. We compared the therapeutic effects of CBD and risperidone (RISP) in a rat model of SCZ induced by sub-chronic ketamine (KET), focusing on inflammatory and oxidative stress, and behavioral phenotypes.

METHODS

Rats were pre-treated with KET or saline (SAL) for 10 days followed by CBD or RISP for 8 days. Locomotion, anxiety- and anhedonia-like behavior, and recognition memory were assessed. Oxidative damage as measured by protein carbonyls, thiobarbituric acid reactive substances, and catalase activity, and the inflammation markers myeloperoxidase (MPO) activity and nitrite/nitrate (N/N) concentration ratio were assessed in the prefrontal cortex (PFC), hypothalamus (HYP), hippocampus (HPC), and striatum, brain areas relevant to SCZ.

RESULTS

CBD restored the KET-induced decreased rearing behavior in the OFT, while RISP further decreased rearing. RISP treatment in control rats decreased rearing and elicited an anhedonic-like phenotype, while CBD did not. CBD, but not RISP restored the KET-induced increased levels of MPO activity in the PFC and the striatum, and protein carbonyls in the HPC. Post-KET treatment with RISP but not CBD decreased protein carbonyls in the PFC, and decreased the N/N concentration ratio in the HYP.

CONCLUSION

CBD restored the KET-induced decrease in rearing behavior without inducing an anhedonic-like phenotype as observed with RISP. CBD, and to a lesser extent RISP restored the oxidative stress and neuroinflammation elicited by KET in the striatum, HPC, and PFC. These findings support the possibility that the antipsychotic effects of CBD might be mediated by its antioxidant and anti-inflammatory effects.

Repeated Administration of a Full-Spectrum Cannabidiol Product, Not a Cannabidiol Isolate, Reverses the Lipopolysaccharide-Induced Depressive-Like Behavior and Hypolocomotion in a Rat Model of Low-Grade Subchronic Inflammation

Background: Mounting evidence suggests that the phytocannabinoid cannabidiol (CBD) holds promise as an antidepressant agent in conditions underlined by inflammation. Full-spectrum CBD extracts might provide greater behavioral efficacy than CBD-only isolates and might require lower doses to achieve the same outcomes due to the presence of other cannabinoids, terpenes, and flavonoids. However, investigations in this area remain limited. Methods: We evaluated the behavioral response to the administration for 7 days of 15 and 30 mg/kg of a CBD isolate and a full-spectrum CBD product in a rat model of subchronic lipopolysaccharide (LPS, 0.5 mg/kg/day/7 days, intraperitoneal)-induced depressive-like and sickness behavior. The forced swim test was used to assess depressive-like behavior, the open field test (OFT) to assess locomotion, and the elevated plus maze to assess anxiety-like behavior. Results: The full-spectrum CBD extract at both doses, but not the CBD isolate, reversed the LPS-induced depressive-like behavior in the forced swim test. Moreover, the full-spectrum CBD extract at the higher dose but not the CBD isolate restored the subchronic LPS-induced hypolocomotion in the OFT. Repeated administration of both formulations elicited an anxiogenic-like trend in the elevated plus maze. Conclusion: Full-spectrum CBD products might have greater therapeutic efficacy in resolving inflammation-induced depressive and sickness behavior compared to a CBD-only isolate.

Unlocking the Antidiabetic Potential of CBD: In Vivo Preclinical Studies

Background/Objectives: Diabetes mellitus is a growing global health concern, driving the exploration of new therapies like cannabidiol (CBD), which shows potential in improving insulin sensitivity and glycemic control, though its effects on glucose metabolism remain unclear. This study evaluates CBD's dose-dependent effects on glycemia, insulin, and hepatic carbohydrate metabolism in diabetic rats. Methods: The Oral Glucose Tolerance Test (OGTT) was performed in healthy rats to compare intragastric vs. intraperitoneal CBD (0.5, 5, 50 mg/kg). Diabetic rats were treated with intragastric CBD (25, 50, 100 mg/kg) or metformin (70 mg/kg) for 8 days. Blood glucose, insulin, lipid profiles, and key carbohydrate-metabolizing enzymes were analyzed. Results: In the OGTT, intragastric CBD reduced glycemic AUC, with 50 mg/kg showing the strongest effect, while intraperitoneal CBD had no impact. In diabetic rats, metformin and 25 mg/kg CBD lowered blood glucose, but only CBD increased insulin. The 50 mg/kg dose caused the greatest glucose reduction and moderate insulin rise, while 100 mg/kg had no effect. At 25 mg/kg, CBD inhibited glucose-6-phosphatase and increased glucose-6-phosphate. The 50 mg/kg dose further suppressed gluconeogenic enzymes, reduced glycogen phosphorylase and liver glucose, and enhanced glucose-6-phosphate, showing the strongest metabolic effects. The 100 mg/kg dose increased hexokinase but had weaker metabolic effects. Metformin improved glucose utilization and glycogen storage. CBD at 25 and 50 mg/kg reduced triacylglycerols and increased HDL, while 100 mg/kg had no effect. Conclusions: This study provides strong evidence of CBD's antidiabetic potential, especially at 50 mg/kg, particularly through its modulation of glucose metabolism and tendency to regulate insulin levels.

Cannabidiol attenuates precuneus activation during appetitive cue exposure in individuals with alcohol use disorder

Alcohol use disorder (AUD) is a prevalent psychiatric condition characterised by problematic alcohol consumption and craving, necessitating the exploration of novel therapeutic interventions. Cannabidiol (CBD), a non-psychoactive component of cannabis, has shown potential in modulating neural processes associated with substance use disorders including AUD. This study aimed to investigate the effect of CBD on alcohol cue-induced activation of neurocircuitry associated with alcohol craving, and impact on mood, craving, and cognitive functioning in individuals with AUD. In a cross-over, double-blind, randomized trial, 22 non-treatment seeking individuals (M = 29 years) diagnosed with AUD (DSM-V) received either 800 mg of CBD or a matched placebo, completing two respective fMRI sessions. The primary outcome was neural activation in response to alcohol versus control visual cues, measured using a functional magnetic resonance imaging (fMRI) alcohol cue reactivity task. Secondary outcomes included assessments of mood, craving, and cognitive functioning. Region of interest analyses showed no differences in alcohol cue-elicited activation between the CBD and placebo conditions. However, exploratory whole-brain analysis indicated a significant treatment effect of CBD in the precuneus which was independent of cue specificity. There were no significant treatment effects of CBD compared to placebo on acute craving, mood, or cognitive functioning. In non treatment seeking individuals with AUD, CBD modulates precuneus activity during alcohol cue exposure. Further studies examining the effect of CBD on treatment-seeking AUD individuals are warranted.

Impact of cannabinoids on cancer outcomes in patients receiving immune checkpoint inhibitor immunotherapy

Cannabinoids relieve pain, nausea, anorexia and anxiety, and improve quality of life in several cancer patients. The immunotherapy with checkpoint inhibitors (ICIs), although very successful in a subset of patients, is accompanied by moderate to severe immune-related adverse events (ir-AE) that often necessitate its discontinuation. Because of their role in symptomatic relief, cannabinoids have been used in combination with immune checkpoint inhibitor (ICI) immunotherapy. A few studies strongly suggest that the use of medicinal cannabis in cancer patients attenuates many of the ir-AE associated with the use of ICI immunotherapy and increase its tolerability. However, no significant beneficial effects on overall survival, progression free survival or cancer relapses were observed; rather, some of the studies noted adverse effects of concurrent administration of cannabinoids with ICI immunotherapy on the clinical benefits of the latter. Because of cannabinoids' well documented immunosuppressive effects mediated through the cannabinoid recptor-2 (CB2), we propose considering this receptor as an inhibitory immune checkpoint per se. A simultaneous neutralization of CB2, concurrent with cannabinoid treatment, may lead to better clinical outcomes in cancer patients receiving ICI immunotherapy. In this regard, cannabinoids such as cannabidiol (CBD) and cannabigerol (CBG), with little agonism for CB2, may be better therapeutic choices. Additional strategies e.g., the use of monoacylglycerol lipase (MAGL) inhibitors that degrade some endocannabinoids as well as lipogenesis and formation of lipid bilayers in cancer cells may also be explored. Future studies should take into consideration gut microbiota, CYP450 polymorphism and haplotypes, cannabinoid-drug interactions as well as genetic and somatic variations occurring in the cannabinoid receptors and their signaling pathways in cancer cells for personalized cannabis-based therapies in cancer patients receiving ICIs. This may lead to rational knowledge-based regimens tailored to individual cancer patients.

An Overview of the Potential for Pharmacokinetic Interactions Between Drugs and Cannabis Products in Humans

Cannabis is the most commonly used illicit substance worldwide. Recent years have seen an increase in cannabis consumption, and with new approvals and therapeutic indications, there are challenges in minimizing the risks and interactions between cannabis-based products, cannabis prescription drugs, other approved prescription drugs, and other substances of abuse. Thus, identifying the enzymes metabolizing cannabinoid drugs and their relationship with other prescription drugs is crucial for understanding the potential interactions and effects of their simultaneous use. This article offers a comprehensive review of cannabis and the pharmacokinetic interactions between cannabis products, cannabis prescription drugs, and other approved prescription drugs, as well as other substances of abuse. It also compiles existing evidence of these interactions and describes the clinical outcomes associated with the inhibition or induction of various enzymes.

Alternative and Complimentary Medication Use in Singers: A Pilot Survey

OBJECTIVE

Cannabidiol (CBD) is an active ingredient in marijuana that has demonstrated anti-inflammatory properties. It's therapeutic potential and accessibility has made the product popular. Over the counter products (OTC) products have also demonstrated therapeutic potential and have been accessible in public markets for a long time. The objective was to better understand the use of CBD and OTC products amongst singers with varying singing styles.

METHODS

An anonymous online survey was distributed to 1053 singers via The Research Electronic Data Capture (RED-Cap) program in association with Drexel University. The survey aimed to obtain information regarding singing proficiency, styles, if respondents used CBD/OTC products, reasons for use, perceived effects on the voice due to use of these products, and how informed were they in regards to use of these products.

RESULTS

From 1053 singers, we obtained 144 respondents (response rate of 13.7%). The average age of respondents was 51.8 years; There were 47 males, 93 females, and four who were nonbinary or preferred not to provide their gender. The majority of respondents (63.2%) were professional singers. Primary singing styles included operatic (18.1%), sacred (20.8%), and musical theater (20.1%). Eighty-seven point five percent of respondents reported warming up before singing and 22.9% reported cooling down after singing. Thirteen respondents reported use of a cannabidiol (CBD) product. Information resources for CBD used primarily came from an online website (38.5%). Among the 13 respondents who reported use of CBD products, 46.2% of these respondents did not notice any positive effects and 46.2% reported no negative effects on the voice when using CBD products. Eighty-two respondents (56.9%) reported use of an OTC, supplement, or alternative medicine product. Majority received Information resources from a physician or other healthcare provider (81.7%). The most frequently reported OTC or complimentary medications used were reflux medications, antihistamines, acetaminophen, and NSAIDs. Reduced inflammation, improved voice recovery, improved voice quality, and improved voice endurance were commonly reported positive effects on the voice with OTC/AM use. Vocal strain, hoarseness, and dryness were the most commonly reported negative effects on the voice with OTC/AM use.

CONCLUSIONS

Stress, anxiety, or chronic pain was often the primary reason for CBD use amongst singers. The most common OTC medications were used reflux medications, antihistamines, acetaminophen, and NSAIDs.

[Recommendations of the DGRh Committee on Complementary Medicine and Nutrition on the application of selected phytotherapeutic drugs and herbal medicines in rheumatology]

BACKGROUND

Herbal preparations and phytotherapeutic substances are offered for symptoms and diseases of the rheumatic spectrum and are often intensively advertised in the lay press. The German Society for Rheumatology and Clinical Immunology (DGRh) Committee on Complementary Medicine and Nutrition reviewed the scientific literature on selected over the counter preparations and prescription phytotherapeutic substances and examined the possibilities for their use in rheumatology.

METHODS

In an online meeting of the Committee on 8 February 2023 a list of herbal preparations that are frequently used in rheumatology (mostly as self-medication) was drawn up. Each member of the committee then carried out a literature search on one or two substances and summarized the results according to a defined matrix. Research was carried out on borage oil, stinging nettle preparations, cannabis preparations and preparations of dog rose, rosemary, saffron and willow bark. The data on the mixed preparation Phytodolor® (Bayer Vital GmbH, Germany) were also examined. The results were reviewed by a circulation procedure and approved in two further online meetings of the Committee. After review by the DGRh board, the recommendations were transferred to the professional organization's website.

RESULTS

Even though there are reports of anti-inflammatory or immunological effects in vitro and/or in animal models for all the plant substances examined, the evidence for a clinically relevant benefit is sparse. None of the preparations investigated has a therapeutic efficacy that justifies its use in inflammatory joint diseases. Herbal preparations based on saffron and rosemary are generally not recommended. Borage oil from seeds can be taken in standardized form as part of a health-conscious diet but is not expected to have any significant anti-inflammatory effect. Rheumatologists need not advise against Phytodolor® or preparations based on stinging nettle, willow bark or dog rose, which are taken on the patient's initiative for degenerative joint diseases, if a sensible therapy concept is otherwise adhered to. There is insufficient evidence to prescribe medicinal cannabis for inflammatory rheumatic diseases for disease modification or symptomatic therapy. In individual cases, however, its use to reduce chronic pain, particularly neuropathic pain and sleep disorders and to reduce opiate consumption may be justified.

CONCLUSION

Even if the herbal preparations presented here must be considered in a differentiated manner for rheumatology practice, the value of phytotherapy for the discipline is low.

CBD and the 5-HT1A receptor: A medicinal and pharmacological review

Cannabidiol (CBD), a phytocannabinoid, has emerged as a promising candidate for addressing a wide array of symptoms. It has the ability to bind to multiple proteins and receptors, including 5-HT1AR, transient receptor potential vanilloid 1 (TRPV1), and cannabinoid receptors. However, CBD's pharmacodynamic interaction with 5-HT1AR and its medicinal outcomes are still debated. This review explores recent literature to elucidate these questions, highlighting the neurotherapeutic outcomes of this pharmacodynamic interaction and proposing a signaling pathway underlying the mechanism by which CBD desensitizes 5-HT1AR signaling. A comprehensive survey of the literature underscores CBD's multifaceted neurotherapeutic effects, which include antidepressant, anxiolytic, neuroprotective, antipsychotic, antiemetic, anti-allodynic, anti-epileptic, anti-degenerative, and addiction-treating properties, attributable in part to its interactions with 5-HT1AR. Furthermore, evidence suggests that the pharmacodynamic interaction between CBD and 5-HT1AR is contingent upon dosage. Moreover, we propose that CBD can induce desensitization of 5-HT1AR via both homologous and heterologous mechanisms. Homologous desensitization involves the recruitment of G protein-coupled receptor kinase 2 (GRK2) and β-arrestin, leading to receptor endocytosis. In contrast, heterologous desensitization is mediated by an elevated intracellular calcium level or activation of protein kinases, such as c-Jun N-terminal kinase (JNK), through the activity of other receptors.

Ion channels and G protein-coupled receptors: Cannabidiol actions on disorders of excitability and synaptic excitatory-inhibitory ratio

Brain excitability is dysfunctional in epilepsy and overlapping neuropsychiatric conditions including autism spectrum disorder (ASD). Epilepsy and ASD are often attributed to malfunctioning coordination between synaptic excitation and inhibition. Dravet syndrome (DS) is a severe form of epilepsy arising from haploinsufficiency of the SCN1A gene that encodes the voltage-gated sodium channel Nav1.1. A DS mouse model (Scn1a+/-) recapitulated essential features of DS and revealed that sodium current density was profoundly reduced in GABAergic inhibitory interneurons while pyramidal cells were spared, suggesting that DS is an "interneuronopathy." Further studies from the Catterall group and others have expanded this picture: DS symptoms, which include recurrent seizures, ataxia, cognitive impairment, ASD, and premature death, could be assigned in part to brain region-specific effects; the Nav1.1 mutations cause dysfunction in some subtypes of interneurons, not others, and are temporally restricted; DS-causing sodium channel mutations were found throughout SCN1A as well as in SCN1B, encoding the β1 subunit. Interest in therapeutic approaches was sparked by preclinical studies of cannabidiol (CBD) that led to the 2018 US Food and Drug Administration approval for treatment of seizures in patients with DS. Independent evidence showed that CBD antagonized GPR55, a G protein-coupled receptor activated by the lipid signaling molecule lysophosphatidylinositol (LPI). We summarized evidence from our group and others that CBD has a dual mechanism of action, targeting both ion channels and GPR55. CBD quells an epileptogenic vicious cycle: seizures strengthen LPI-GPR55 signaling while LPI-GPR55 signaling elevates the synaptic excitatory-inhibitory ratio, thereby promoting further seizures. SIGNIFICANCE STATEMENT: Modern medicine relies on ion channels and G protein-coupled receptors (GPCRs) as key targets. In studies of Dravet syndrome, a devastating genetic disorder with features of epilepsy and autism, William Catterall connected NaV1.1 mutations to deficient excitability of inhibitory neurons. He and his colleagues explored preclinical interventions using cannabidiol (CBD) and clobazam, opening the way to a current understanding of CBD's therapeutic mechanism. CBD affects both ion channels and GPR55, a GPCR activated by lysophosphatidylinositol, an activity-dependent lipid messenger, readjusting the synaptic excitatory-inhibitory ratio.

Cannabidiol induces autophagy via CB1 receptor and reduces α-synuclein cytosolic levels

Numerous studies have explored the role of cannabinoids in neurological conditions, chronic pain and neurodegenerative diseases. Restoring autophagy has been proposed as a potential target for the treatment of neurodegenerative diseases. In our study, we used a neuroblastoma cell line that overexpresses wild-type α-synuclein to investigate the effects of cannabidiol on autophagy modulation and reduction in the level of cytosolic α-synuclein. Our results demonstrated that cannabidiol enhances the accumulation of LC3-II- and GFP-LC3-positive vesicles, which indicates an increase in autophagic flux. In addition, cannabidiol-treated cells showed a reduction in cytosolic α-synuclein levels. These effects were inhibited when the cells were treated with a CB1 receptor-selective antagonist, which indicates that the biological effects of cannabidiol are mediated via its interaction with CB1 receptor. Additionally, we also observed that cannabinoid compounds induce autophagy and α-synuclein degradation after they interact with the CB1 receptor. In summary, our data suggest that cannabidiol induces autophagy and reduces cytosolic α-synuclein levels. These biological effects are mediated preferentially through the interaction of cannabidiol with CB1 receptors, and therefore, cannabinoid compounds that act selectively on this receptor could represent a new approach for autophagy modulation and degradation of protein aggregates.

Pharmacological characterization of cannabidiol as a negative allosteric modulator of the 5-HT2A receptor

Promising clinical evidence suggests that psychedelic compounds, like lysergic acid diethylamide (LSD), have therapeutic value for treatment of psychiatric disorders. However, they often produce hallucinations and dissociative states, likely mediated by the serotonin (5-HT) receptor 5-HT2A, raising challenges regarding therapeutic scalability. Given the reported antipsychotic effects of cannabidiol (CBD) and its promiscuous binding at many receptors, we assessed whether CBD could modulate 5-HT2A signalling. Activation of the 5-HT2A intracellular signalling events were assessed using resonance energy transfer- or fluorescence-based biosensors in HEK 293 cells and in rat primary cortical neurons. In 5-HT2A-transfected HEK 293 T cells, CBD antagonized LSD-mediated Gq activation in a saturable way, while leaving β-arrestin2 recruitment unaffected. CBD decreased Gq activation mediated by the 5-HT2A-specific agonist DOI as well as LSD-mediated activity in primary rat neonatal cortical neurons. Using Site Identification by Ligand Competitive Saturation (SILCS) simulations, we also predicted that the putative binding site of CBD overlapped with that of oleamide, a positive allosteric modulator of 5-HT2A, and could displace the binding of orthosteric ligands toward the external binding pocket. Based on these findings, we propose that CBD acts as a negative allosteric modulator of 5-HT2A.

Isobolographic interactions of cannabidiol and AM 1172 with cisplatin in human neuroblastoma and glioblastoma cell lines: An in vitro study

Glioblastoma is the most aggressive brain cancer in humans with very poor prognosis and high mortality rate. Despite advances in treatment, glioblastoma almost always recurs and new therapeutic methods are urgently needed. This study aimed at assessing the cytotoxic and antiproliferative effects of AM 1172 and cannabidiol (two cannabinoid receptor ligands) in vitro, when used alone and in combination with cisplatin (a standard cytotoxic drug), in various human neuroblastoma (CHP-134, KELLY), human glioblastoma (U-87MG and T98G) and rat glioblastoma (C6) cell lines. Our experiments showed that AM 1172 and cannabidiol inhibited cell proliferation with IC50 values in the range of 2.29-17.21 μM (for AM 1172) and 11.61-20.35 μM (for cannabidiol), respectively. The selectivity index for AM 1172 ranged from 0.61 to 4.60 and that for cannabidiol ranged from 1.45 to 2.55 in the studied glioblastoma and neuroblastoma cell lines. With isobolographic analysis, it was found that AM 1172 combined with cisplatin exerted a synergistic interaction in the CHP-134 cell line (p < 0.01). In contrast, AM 1172 when combined with cisplatin produced an antagonistic interaction in the C6 cell line (p < 0.01). The remaining combinations of AM 1172 with cisplatin in the U-87MG, KELLY and T98G cell lines were additive. In case of cannabidiol, its combination with cisplatin produced an antagonistic interaction in the T98G cell line (p < 0.0001), whereas the combinations of cannabidiol with cisplatin in the CHP-134, U-87MG, KELLY, and C6 cell lines were additive in nature. The synergistic and additive interactions for the combination of AM 1172 and cannabidiol with cisplatin seem to be a promising direction in glioblastoma therapy. Unfortunately, the combinations producing antagonistic interactions (AM 1172+cisplatin in C6, and cannabidiol + cisplatin in T98G cell lines) should be avoided due to the antagonistic antiproliferative effect of two-drug mixtures.

Determination of the Negative Allosteric Binding Site of Cannabidiol at the CB1 Receptor: A Combined Computational and Site-Directed Mutagenesis Study

Cannabinoid receptor 1 (CB1R) has been extensively studied as a potential therapeutic target for various conditions, including pain management, obesity, emesis, and metabolic syndrome. Unlike orthosteric agonists such as Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD) has been identified as a negative allosteric modulator (NAM) of CB1R, among its other pharmacological targets. Previous computational and structural studies have proposed various binding sites for CB1R NAMs. An X-ray crystal structure revealed a binding site for the NAM, ORG27569, at an extrahelical location within the inner leaflet of the membrane. In contrast, multiple computational studies have previously proposed several potential allosteric binding sites for CBD within the CB1R structure. Given that a prior structural study suggested CBD might occupy the same site as ORG27569, we conducted a comprehensive investigation of potential CBD binding sites using molecular docking, molecular dynamics (MD) simulations, metadynamics (MTD) simulations, binding free-energy calculations, and in vitro mutagenesis experiments. Molecular docking, MD, and MTD simulations results, along with binding free-energy calculations, suggest that CBD may potentially bind to either the same extrahelical site as ORG27569 or a previously unidentified intracellular site located near TMHs 2, 6, and 7 and helix 8. This intracellular site is consistent with allosteric binding sites observed in other G protein-coupled receptors (GPCRs). To establish the most favorable allosteric site for CBD, we conducted site-directed mutagenesis of key residues at each site. Mutations at S4018.47ΔA and D4038.49ΔA augmented the binding of [3H]-SR141716A, suggesting these residues play critical roles in CBD binding. As a result, the combined computational and mutagenesis results identified a binding site for CBD between TMHs 2, 6, and 7 and helix 8, involving residues Y1532.40, I1562.43, M3376.29, L3416.33, S4018.47, and D4038.49. These findings provide valuable insights into how CBD binds to CB1R, thereby informing the rational design of new, selective, and potent NAMs. Moreover, the elucidation of this previously unexplored allosteric site might explain the polypharmacology of CBD due to structural conservation among Class A GPCRs.

Combined effects of cannabidiol and Δ9-tetrahydrocannabinol alleviate migraine-like symptoms in mice

BACKGROUND

The therapeutic use of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) to treat migraine has been understudied. Using three mouse models, we examined the impact of CBD and THC on migraine-relevant behaviors triggered by: 1) calcitonin gene-related peptide (CGRP), 2) sodium nitroprusside (SNP), and 3) cortical spreading depolarization (CSD).

METHODS

Both male and female CD1 mice were treated with CBD (100 mg/kg) or THC (1 mg/kg) alone or in combinations of CBD (1, 30 or 100 mg/kg) and THC (1 mg/kg) prior to injection of CGRP or SNP. The mice were assessed for light aversion (photophobia), squint (non-evoked pain), and periorbital tactile hypersensitivity, as well as possible adverse effects. In a separate set of experiments, CSD events were optogenetically induced in familial hemiplegic migraine 1 (FHM1) mutant and wildtype littermates (WT) mice (C57BL/6 background), followed by grimace and motor assessments with and without combinations of CBD (30 or 100 mg/kg) and THC (1 mg/kg).

RESULTS

In CD1 mice, a 100:1 CBD:THC combination mitigated light aversion induced by CGRP and SNP in males and females. Rescue of CGRP- and SNP-induced squint was observed only in male mice with 100:1 CBD:THC. None of the treatments rescued periorbital tactile hypersensitivity in either sex. In FHM1 mutant and WT mice, the 100:1 CBD:THC ratio did not affect CSD characteristics but did reduce CSD-induced grimace features (i.e., head pain mimic). No adverse effects of any of the cannabinoid treatments were observed using cognitive, emotional, or motor tests.

CONCLUSIONS

A 100:1 ratio of CBD:THC has a beneficial effect on some of the most bothersome migraine-related symptoms in three mouse models. Our findings support a potential therapeutic efficacy of combined CBD and THC treatments.

Acute cannabidiol treatment reverses behavioral impairments induced by embryonic valproic acid exposure in male mice

Cannabidiol (CBD), the major non-psychotomimetic compound of the Cannabis sativa plant, has shown promising effects in addressing various symptoms associated with autism spectrum disorder (ASD). This neurodevelopmental disorder typically impacts cognitive, behavioral, social communication, and motor skills domains. However, effective treatments for the wide range of symptoms associated with the disorder are limited and may trigger undesirable effects. Embryonic exposure to valproic acid (VPA, 500 mg/kg at 12° day embryonic age) in rodents is a consolidated environmental model for studying behavioral and molecular characteristics related to ASD. Therefore, this study aimed to evaluate whether acute CBD could reverse behavioral impairments in adult mice (eight weeks) exposed to VPA in the embryonic period in four distinct trials. In independent groups of animals, the following assays were conducted: I) Pre-Pulse Inhibition Test (PPI), II) Marble Burying, III) Social Interaction, IV) Actimeter Test, and V) Novel Object Recognition Test (NOR). In the PPI paradigm, mice exposed to VPA showed PPI impairment, and CBD (30 and 60 mg/kg) reversed this disruption. CBD (60 mg/kg) respectively decreased the number of buried marbles, improved social interaction time, but failed to reduce stereotyped-like movements in the VPA group. In NOR test CBD at both doses reversed the impairment in index of recognition induced in VPA group. These findings suggest that acute CBD administration can ameliorate behavioral impairments associated with ASD in a well-established animal model for studying this neurodevelopmental disorder.

Cannabidiol enhances socially transmitted food preference: a role of acetylcholine in the mouse basal forebrain

RATIONALE AND OBJECTIVE

Rodents acquire food information from their conspecifics and display a preference for the conspecifics' consumed food. This social learning of food information from others promotes the survival of a species, and it is introduced as the socially transmitted food preference (STFP) task. The cholinergic system in the basal forebrain plays a role in the acquisition of STFP. Cannabidiol (CBD), one of the most abundant phytocannabinoids, exerts its therapeutic potential for cognitive deficits through versatile mechanisms of action, including its interaction with the cholinergic system. We hypothesize a positive relationship between CBD and STFP because acetylcholine (ACh) is involved in STFP, and CBD increases the ACh levels in the basal forebrain.

MATERIALS AND METHODS

Male C57BL/6J mice were trained to acquire the STFP task. We examined whether CBD affects STFP memory by administering CBD (20 mg/kg, i.p.) before the STFP social training. The involvement of cholinergic system in CBD's effect on STFP was examined by knockdown of brain acetylcholinesterase (AChE), applying a nonselective muscarinic antagonist SCO (3 mg/kg, i.p.) before CBD treatment, and measuring the basal forebrain ACh levels in the CBD-treated mice.

RESULTS

We first showed that CBD enhanced STFP memory. Knockdown of brain AChE also enhanced STFP memory, which mimicked CBD's effect on STFP. SCO blocked CBD's memory-enhancing effect on STFP. Our most significant finding is that the basal forebrain ACh levels in the CBD-treated mice, but not their control counterparts, were positively correlated with mice's STFP memory performance.

CONCLUSION

This study indicates that CBD enhances STFP memory in mice. Specifically, those which respond to CBD by increasing the muscarinic-mediated ACh signaling perform better in their STFP memory.

Oral cannabidiol did not impair learning and memory in healthy adults

BACKGROUND

The effect of oral Cannabidiol (CBD) on interference during learning and memory (L&M) in healthy human volunteers has not been studied.

METHOD

A two-arm crossover, randomized, double-blind, placebo-controlled trial was conducted at Colorado State University Pueblo (CSU Pueblo) to evaluate the effects of 246 mg oral CBD on L&M in healthy adults. Among 57 healthy volunteers enrolled, 35 were included in the analyses. For assessment of L&M, Montreal Cognitive Assessment (MOCA) was used to evaluate verbal baseline cognitive function; RAVLT-R tests (List A and List B recalls, Proactive and Retroactive Interference ratios, and Forgetting Speed ratio) were used to evaluate verbal declarative memory; and total prose recall was used to evaluate verbal logical memory. Linear Mixed Models with Bonferroni Corrections were used to compare L&M results between primary outcomes (CBD vs. placebo) and secondary demographic outcomes, with a two-tailed statistical significance of P < 0.05.

RESULTS

CBD administration did not affect any of the dependent variables measured compared to the placebo group. There were no effects of THC, history of CBD use, or sex on CBD's modulation of L&M. However, a highly significant interaction effect between treatment groups (CBD vs. placebo) and age of subjects was observed for the PI ratio (P = 0.008; n = 35).

CONCLUSIONS

The results of this study suggest that administration of oral CBD alone does not significantly impair L&M in healthy adults. However, age might influence CBD related modulation of proactive interference during human L&M. Future research involving a larger group of older adults is needed to confirm this potential effect.

TRIAL REGISTRATION

The study was approved by the CSU Pueblo IRB, conducted in accordance with the Declaration of Helsinki, and registered with ClinicalTrials.gov (NCT06074172).

Do Delta-9-tetrahydrocannabinol and Cannabidiol have opposed effects on male fertility?

Cannabis sativa is a complex plant, renowned for its diverse array of bioactive compounds, the most prominent of which are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). These compounds exhibit markedly opposing pharmacological effects, with THC being primarily psychoactive and CBD known for its non-psychoactive properties. In recent years, there has been growing interest in the potential health implications of these compounds, particularly concerning male reproductive health. Accumulating evidence over the past decade has alluded to the potential negative effects of THC, including its association with reduced sperm quality, altered hormone levels, changes in genetic and epigenetic profiles, and potential impacts on fertility. Conversely, emerging studies suggest that CBD may exert protective and beneficial effects on male reproductive health, possibly through its anti-inflammatory and antioxidant properties. This review aims to provide a comprehensive analysis of the current scientific literature, delineating the mechanisms by which THC and CBD influence male reproductive health, highlighting the disparities in their effects, and discussing the clinical and therapeutic implications of these findings.

Stereoisomers of cannabidiols and their pharmacological activities - A potentially novel direction for cannabinoids

Cannabidiol (CBD), a bicyclic non-psychoactive cannabinoid biosynthesized by Cannabis spp. of plants, has attracted significant interest in the past decade due to its therapeutic properties. In 2018, the US FDA approved Epidiolex®, a CBD-based drug for the treatment of two rare epileptic seizure disorders. CBD possesses two chiral centers at C3 and C4 on its terpenoid moiety and exhibits cis-trans stereoisomerism along the C3-C4 bond axis. (-)-trans-(3R,4R)-CBD, the natural CBD, is biosynthesized by the cannabis plant, while the unnatural (+)-trans-(3S,4S)-CBD is obtained via chemical synthesis. Both trans isomers exhibit broad in vitro and in vivo biological activities; typically, the unnatural stereoisomer (+)-trans-CBD and its derivatives exhibited more potent activities in comparison to the corresponding (-)-trans isomers. On the other hand, cis-CBD isomers have only been reported recently and can undergo epimerization into trans isomers. There is a significant opportunity to explore unique synthetic methods and biological activities of stereoisomers of CBD that may pave the path for the development of novel therapeutics. Herein, as a novel direction in cannabinoids, we review the chemistry of CBD stereoisomers, their structure-activity relationships, target selectivity and efficacy in animal models.

Chronic cannabidiol treatment induces cardiovascular improvement in renovascular hypertensive rats

BACKGROUND

Cannabidiol (CBD) is increasingly studied for its therapeutic potential in neurodegenerative diseases. Previous research on acute CBD administration has demonstrated cardiovascular benefits in hypertensive rats, including reduced mean blood pressure and oxidative stress.

AIM

To investigate the long-term cardiovascular effects of chronic CBD treatment in renovascular hypertension induced by the 2-kidney-1-clip (2K1C) model.

METHODS

Male Wistar rats (180-200 g, 8 weeks old) underwent 2K1C or SHAM surgery. Six weeks later, rats received chronic CBD treatment (20 mg/kg, twice daily for 14 days). A combination of ex vivo, in vitro, and in vivo methods was used to assess CBD's cardiovascular effects in 2K1C hypertensive rats.

RESULTS

Chronic CBD treatment significantly reduced blood pressure and the depressor response to hexamethonium (a ganglionic blocker). It also normalized variability in low-frequency (LF) power and LF/high-frequency (HF) ratio. CBD enhanced vasodilation and reduced vasoconstriction in the mesenteric artery of 2K1C rats, accompanied by decreased expression of aortic reactive oxygen species (ROS).

CONCLUSION

Our findings suggest that chronic CBD treatment exerts antihypertensive effects by improving baroreflex sensitivity and vascular function while decreasing arterial ROS levels and sympathetic nerve activity. These results underscore CBD's potential therapeutic role in managing cardiovascular complications associated with renovascular hypertension.

Decoding the Therapeutic Potential of Cannabis and Cannabinoids in Neurological Disorders

For millennia, Cannabis sativa has served diverse roles, from medicinal applications to recreational use. Despite its extensive historical use, only a fraction of its components have been explored until recent times. The therapeutic potential of Cannabis and its constituents has garnered attention, with suggestions for treating various conditions such as Parkinson's disease, epilepsy, Alzheimer's disease, and other neurological disorders. Recent research, particularly on animal experimental models, has unveiled the neuroprotective properties of cannabis. This neuroprotective effect is orchestrated through numerous G protein-coupled receptors (GPCRs) and the two cannabinoid receptors, CB1 and CB2. While the capacity of cannabinoids to safeguard neurons is evident, a significant challenge lies in determining the optimal cannabinoid receptor agonist and its application in clinical trials. The intricate interplay of cannabinoids with the endocannabinoid system, involving CB1 and CB2 receptors, underscores the need for precise understanding and targeted approaches. Unravelling the molecular intricacies of this interaction is vital to harness the therapeutic potential of cannabinoids effectively. As the exploration of cannabis components accelerates, there is a growing awareness of the need for nuanced strategies in utilizing cannabinoid receptor agonists in clinical settings. The evolving landscape of cannabis research presents exciting possibilities for developing targeted interventions that capitalize on the neuroprotective benefits of cannabinoids while navigating the complexities of receptor specificity and clinical applicability.

The Role of Cannabinoids and the Endocannabinoid System in the Treatment and Regulation of Nausea and Vomiting

Despite using the recommended anti-emetic treatments, control of nausea and vomiting is still an unmet need for cancer patients undergoing chemotherapy treatment. Few properly controlled clinical trials have evaluated the potential of exogenously administered cannabinoids or manipulations of the endogenous cannabinoid (eCB) system to treat nausea and vomiting. In this chapter, we explore the pre-clinical and human clinical trial evidence for the potential of exogenous cannabinoids and manipulations of the eCB system to reduce nausea and vomiting. Although there are limited high-quality human clinical trials, pre-clinical evidence suggests that cannabinoids and manipulations of the eCB system have anti-nausea/anti-emetic potential. The pre-clinical anti-nausea/anti-emetic evidence highlights the need for further evaluation of cannabinoids and manipulations of eCBs and other fatty acid amides in clinical trials.

Renal Outcomes and Other Adverse Effects of Cannabinoid Supplementation

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

Cannabinoids for treating psychiatric disorders in youth: a systematic review of randomized controlled trials

BACKGROUND

Cannabinoids have been of increasing interest mainly due to their putative efficacy in a wide array of psychiatric, psychosomatic, and neurological conditions.

AIMS

This systematic review aims to synthesize results from randomized placebo-controlled trials regarding the efficacy and the dosage of cannabinoids as therapeutics in psychiatric disorders in children, adolescents, and young adults.

METHODS

All publications up to June 30th, 2024, were included from PubMed and Embase. Eligibility criteria in accordance with the PRISMA-guidelines was applied. RCTs providing pre- and post-treatment parameters on cannabinoid therapies for mental disorders in comparison to controls in an age range from 0 to 25 years were included. Effect sizes were calculated as Hedges' g for primary outcomes, and a multilevel random-effects meta-analysis was conducted to account for dependent outcomes from same study populations.

RESULTS

We identified 7603 records, of which 8 independent clinical trials (reported in 9 publications) met the pre-established eligibility criteria, comprising 474 unique participants (245 treatment, 229 control). Analysis of 13 primary outcomes (of 7 clinical trials) revealed a modest positive overall effect for symptom improvement or normalization of brain physiology (Hedges' g = 0.308, 95% CI: 0.167, 0.448). Autism spectrum disorder studies showed the most consistent evidence (g = 0.264, 95% CI: 0.107, 0.421), while other conditions showed wider confidence intervals. Age-stratified analysis showed that adult populations (mean age 23.3 years, n = 5 outcomes) demonstrated higher effect sizes (g = 0.463, SD = 0.402) compared to pediatric populations (mean age 11.8 years, n = 8 outcomes; g = 0.318, SD = 0.212). Whole plant preparations (g = 0.328, 95% CI: 0.083, 0.573) and pharmaceutical cannabinoids (g = 0.292, 95% CI: 0.069, 0.515) showed comparable effects. CBD dosages ranged from 17.5 mg to 600 mg per day, with no significant correlation between dosage and effect size (ρ = -0.014, p = 0.963). Mild to moderate side effects were reported, but no serious adverse events. Risk of bias assessment ranged from low (n = 3) to high (n = 5).

CONCLUSION

While meta-analysis of effect sizes for primary outcomes revealed modest positive effects, particularly for autism spectrum disorders, the current evidence remains insufficient to broadly recommend cannabinoids for treating mental disorders in youth populations. Larger, controlled studies with standardized outcomes are needed to establish definitive clinical recommendations.

Medicinal Cannabis and the Intestinal Microbiome

Historically, the multiple uses of cannabis as a medicine, food, and for recreational purposes as a psychoactive drug span several centuries. The various components of the plant (i.e., seeds, roots, leaves and flowers) have been utilized to alleviate symptoms of inflammation and pain (e.g., osteoarthritis, rheumatoid arthritis), mood disorders such as anxiety, and intestinal problems such as nausea, vomiting, abdominal pain and diarrhea. It has been established that the intestinal microbiota progresses neurological, endocrine, and immunological network effects through the gut-microbiota-brain axis, serving as a bilateral communication pathway between the central and enteric nervous systems. An expanding body of clinical evidence emphasizes that the endocannabinoid system has a fundamental connection in regulating immune responses. This is exemplified by its pivotal role in intestinal metabolic and immunity equilibrium and intestinal barrier integrity. This neuromodulator system responds to internal and external environmental signals while also serving as a homeostatic effector system, participating in a reciprocal association with the intestinal microbiota. We advance an exogenous cannabinoid-intestinal microbiota-endocannabinoid system axis potentiated by the intestinal microbiome and medicinal cannabinoids supporting the mechanism of action of the endocannabinoid system. An integrative medicine model of patient care is advanced that may provide patients with beneficial health outcomes when prescribed medicinal cannabis.

Research and Clinical Practice Involving the Use of Cannabis Products, with Emphasis on Cannabidiol: A Narrative Review

BACKGROUND

Emerging evidence supports cannabidiol (CBD) as a promising therapeutic compound for various health conditions, despite its approval as a medication (product for medical purposes) remaining restricted to a limited range of clinical indications. Simultaneously, the regulation of cannabis-derived products for medicinal and recreational use has expanded their global market availability to meet local community demands. This scenario presents a complex challenge for clinicians, researchers, and industry, as the global appeal of therapeutic uses of CBD is growing more rapidly than the scientific evidence supporting its safety and effectiveness.

OUTCOMES

A narrative review was conducted to discuss the best evidence regarding the pharmacological profile of CBD, its efficacy, and safety within the context of regulation and perspectives on the development of new cannabinoid-based drugs. Key articles addressing the various facets of this issue were selected for comprehensive analysis.

CONCLUSIONS

Clinicians and researchers may face unique challenges in understanding the pharmacological profile of CBD and the prospects for developing its clinical indications, given the heterogeneity of clinical terminologies and the quality and composition of cannabis-based medical products available on the market. More basic and clinical research that complies with regulatory agencies' testing guidelines, such as good manufacturing practices (GMPs), good laboratory practices (GLPs), and good clinical practices (GCPs), is needed to obtain approval for CBD or any other cannabinoid as a therapeutic for broader clinical indications.

ESCAPE Study: Cannabidiol Use in Patients Treated for Substance Use Disorders, Prevalence of Use, and Characteristics of Users

INTRODUCTION

Cannabidiol (CBD) is one of the two primary phytocannabinoids found in cannabis. Its diverse pharmacological properties suggest potential benefits for a wide range of medical conditions. The primary objective of this study was to estimate the prevalence of CBD use among patients being treated for substance use disorder. Additionally, we aimed to characterize the pattern of CBD use and describe the profiles of users.

METHODS

Patients admitted to two substance use disorder departments between May 6, 2020, and July 23, 2021, were included in the study. Sociodemographic, medical and substance use data, including CBD use, were collected. A multiple correspondence analysis (MCA) was performed to identify substance uses most frequently correlated with CBD use. Multivariate analyses were also conducted to identify factors associated with CBD use.

RESULTS

The prevalence of CBD use in the past 12 months among the 183 patients was 38.2%. However, at the time of the study, 63% had stopped using CBD, primarily due to its perceived ineffectiveness and cost. CBD was commonly consumed via inhalation, either by smoking the plant or using e-cigarette liquids. The MCA revealed that while there is no typical profile of CBD users, they were more likely to use sedative substances rather than stimulants. CBD users were younger and more likely to have psychiatric comorbidities.

CONCLUSION

The prevalence of CBD use was notably high. Given the significant risk of drug interactions with CBD and its wide variability in composition, it is crucial for clinicians to routinely inquire about CBD use. The potential for self-therapeutic or recreational use in these patients appears to be underestimated.

Cannabinoid Hyperemesis Syndrome (CHS) - An emerging gastrointestinal disorder and clinical challenge

Nausea and vomiting are not uncommon symptoms resulting in emergency department (ED) or primary care visits. One of the emerging etiologies - Cannabinoid Hyperemesis Syndrome (CHS) remains significantly under-diagnosed, often resulting in unnecessary repeat ED visits and testing. This is in part due to lack of experience with and knowledge about CHS by health care professionals. Characterized by cyclic vomiting, often severe and intractable, it is frequently associated with a form of self-treatment; the compulsive need to take hot showers, and in the context of chronic cannabis use. With increased legalization and resultant accessibility to cannabis containing products, the risk of adverse events is significantly rising. Lack of clinical familiarity with the range of potential deleterious physical and mental health effects associated with cannabis leads to delays in appropriate diagnosis and effective treatment of CHS. Moreover, commonly utilized anti-emetics, such as ondansetron, and similar 5 HT drugs may not fully attenuate symptoms of CHS, and other interventions may be necessary; ultimately abstinence being the most effective long term clinical preventive approach. The objective of this review article is to assist the clinician in identifying the specific clinical characteristics of CHS, distinguishing it from other causes of CVS or nausea and vomiting, to facilitate more rapid, effective interventions. Collaboration with substance use professionals should also be considered during CHS treatment.

In the weeds: A comprehensive review of cannabis; its chemical complexity, biosynthesis, and healing abilities

For millennia, various cultures have utilized cannabis for food, textile fiber, ethno-medicines, and pharmacotherapy, owing to its medicinal potential and psychotropic effects. An in-depth exploration of its historical, chemical, and therapeutic dimensions provides context for its contemporary understanding. The criminalization of cannabis in many countries was influenced by the presence of psychoactive cannabinoids; however, scientific advances and growing public awareness have renewed interest in cannabis-related products, especially for medical use. Described as a 'treasure trove,' cannabis produces a diverse array of cannabinoids and non-cannabinoid compounds. Recent research focuses on cannabinoids for treating conditions such as anxiety, depression, chronic pain, Alzheimer's, Parkinson's, and epilepsy. Additionally, secondary metabolites like phenolic compounds, terpenes, and terpenoids are increasingly recognized for their therapeutic effects and their synergistic role with cannabinoids. These compounds show potential in treating neuro and non-neuro disorders, and studies suggest their promise as antitumoral agents. This comprehensive review integrates historical, chemical, and therapeutic perspectives on cannabis, highlighting contemporary research and its vast potential in medicine.

Multi-level therapeutic actions of cannabidiol in ketamine-induced schizophrenia psychopathology in male rats

Repeated administration of ketamine (KET) has been used to model schizophrenia-like symptomatology in rodents, but the psychotomimetic neurobiological and neuroanatomical underpinnings remain elusive. In parallel, the unmet need for a better treatment of schizophrenia requires the development of novel therapeutic strategies. Cannabidiol (CBD), a major non-addictive phytocannabinoid has been linked to antipsychotic effects with unclear mechanistic basis. Therefore, this study aims to clarify the neurobiological substrate of repeated KET administration model and to evaluate CBD's antipsychotic potential and neurobiological basis. CBD-treated male rats with and without prior repeated KET administration underwent behavioral analyses, followed by multilevel analysis of different brain areas including dopaminergic and glutamatergic activity, synaptic signaling, as well as electrophysiological recordings for the assessment of corticohippocampal and corticostriatal network activity. Repeated KET model is characterized by schizophrenia-like symptomatology and alterations in glutamatergic and dopaminergic activity mainly in the PFC and the dorsomedial striatum (DMS), through a bi-directional pattern. These observations are accompanied by glutamatergic/GABAergic deviations paralleled to impaired function of parvalbumin- and cholecystokinin-positive interneurons, indicative of excitation/inhibition (E/I) imbalance. Moreover, CBD counteracted the schizophrenia-like behavioral phenotype as well as reverted prefrontal abnormalities and ventral hippocampal E/I deficits, while partially modulated dorsostriatal dysregulations. This study adds novel insights to our understanding of the KET-induced schizophrenia-related brain pathology, as well as the CBD antipsychotic action through a region-specific set of modulations in the corticohippocampal and costicostrtiatal circuitry of KET-induced profile contributing to the development of novel therapeutic strategies focused on the ECS and E/I imbalance restoration.

Cannabidiol attenuates prepulse inhibition disruption by facilitating TRPV1 and 5-HT1A receptor-mediated neurotransmission

Individuals with schizophrenia (SCZ) often present sensorimotor gating impairments that can be investigated by the prepulse inhibition test (PPI). PPI disruption can be mimicked experimentally with psychostimulants such as amphetamine and attenuated/reversed by antipsychotics. Cannabidiol (CBD), the main non-psychotomimetic component of the Cannabis sativa plant, produces antipsychotic-like effects in clinical and preclinical studies. CBD can interact with many pharmacological targets, but the mechanisms involved in its antipsychotic activity are unclear. Using amphetamine-induced PPI disruption in mice, we investigated the involvement of four CBD potential pharmacological targets (CB1, CB2 TRPV1, and 5-HT1A receptors) in its antipsychotic properties. CBD effects were blocked by the TRPV1 antagonist capsazepine and, to a greater extent, by the 5-HT1A receptor antagonist WAY100635. No effect was observed with the CB1 (AM251) or CB2 (AM630) receptor antagonists. These results corroborate findings showing the antipsychotic effects of CBD in the PPI model and indicate that they involve the participation of TRPV1 and 5-HT1A receptors.

Cannabis Sativa Oil Promotes Social Interaction and Ultrasonic Communication by Acting on Oxytocin Pathway

Objective: Cannabis sativa is the most used recreational drug worldwide. In recent years, there has been a growing interest in the potential therapeutic benefits of medicinal cannabis to treat a variety of psychiatric and neurological conditions. In particular, cannabidiol (CBD), a nonpsychoactive cannabis constituent, has been investigated for its potential prosocial effects on behavior, although the molecular mechanisms underlying this effect are still largely unknown. The aim of this study was to investigate the effect of a C. sativa oil CBD rich (CS oil) on social interaction and ultrasonic communication in mice. Study Design: Twenty-seven adult male mice (B6; 129P F2) were treated daily with vehicle or CS oil for 2 weeks. At Day 14, mice were tested for behavior (social interaction test and ultrasonic communication). Forty minutes before the behavioral tests, mice were exposed to intranasal treatment with vehicle or the oxytocin receptor antagonist, L-371,257. After behavioral tests, VH- and CS oil-treated mice were sacrificed, RNA was extracted from the hypothalamus and used for quantitative Real Time-PCR experiments. Results: We found that a 2-week treatment with the CS oil on mice exerted a prosocial effect associated with an increase in ultrasonic vocalizations. These effects were inhibited by pretreating mice with an oxytocin receptor antagonist. In addition, at the molecular level, we found that CS oil treatment caused a significant increase in oxytocin and a decrease in oxytocin receptor expression levels in the brain hypothalamus. Conclusion: Our results suggest that CS oil promotes social behavior by acting on oxytocin pathway.

Current and Potential Use of Biologically Active Compounds Derived from Cannabis sativa L. in the Treatment of Selected Diseases

Cannabis sativa L. contains numerous compounds with antioxidant and anti-inflammatory properties, including the flavonoids and the cannabinoids, particularly Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabinoids have an effect on the endocannabinoid system (ECS), a cellular communication network, and are, hence, widely studied for medical applications. Epidiolex®, a 99% pure oral CBD extract, has been approved by the FDA for the treatment of epilepsy. Nabiximols (Sativex) is an oromucosal spray containing equal volume of THC and CBD, and it is commonly used as an add-on treatment for unresponsive spasticity in multiple sclerosis (MS) patients. Several in vitro and in vivo studies have also shown that cannabinoids can be used to treat various types of cancer, such as melanoma and brain glioblastoma; the first positive clinical trials on the anticancer effect of a THC:CBD blend with temozolomide (TMZ) in the treatment of highly invasive brain cancer are very promising. The cannabinoids exert their anticancer properties in in vitro investigations by the induction of cell death, mainly by apoptosis and cytotoxic autophagy, and the inhibition of cell proliferation. In several studies, cannabinoids have been found to induce tumor regression and inhibit angiogenic mechanisms in vitro and in vivo, as well as in two low-numbered epidemiological studies. They also exhibit antiviral effects by inhibiting ACE2 transcription, blocking viral replication and fusion, and acting as anti-inflammatory agents; indeed, prior CBD consumption (a study of 93,565 persons in Chicago) has also been associated with a much lower incidence of SARS-CoV-2 infections. It is postulated that cannabis extracts can be used in the treatment of many other diseases such as systemic lupus erythematosus, type 1 diabetes, or various types of neurological disorders, e.g., Alzheimer's disease. The aim of this review is to outline the current state of knowledge regarding currently used medicinal preparations derived from C. sativa L. in the treatment of selected cancer and viral diseases, and to present the latest research on the potential applications of its secondary metabolites.

The Entourage Effect in Cannabis Medicinal Products: A Comprehensive Review

This study explores the complementary or synergistic effects of medicinal cannabis constituents, particularly terpenes, concerning their therapeutic potential, known as the entourage effect. A systematic review of the literature on cannabis "entourage effects" was conducted using the PRISMA model. Two research questions directed the review: (1) What are the physiological effects of terpenes and terpenoids found in cannabis? (2) What are the proven "entourage effects" of terpenes in cannabis? The initial approach involved an exploratory search in electronic databases using predefined keywords and Boolean phrases across PubMed/MEDLINE, Web of Science, and EBSCO databases using Medical Subject Headings (MeSH). Analysis of published studies shows no evidence of neuroprotective or anti-aggregatory effects of α-pinene and β-pinene against β-amyloid-mediated toxicity; however, modest lipid peroxidation inhibition by α-pinene, β pinene, and terpinolene may contribute to the multifaceted neuroprotection properties of these C. sativa L. prevalent monoterpenes and the triterpene friedelin. Myrcene demonstrated anti-inflammatory proprieties topically; however, in combination with CBD, it did not show significant additional differences. Exploratory evidence suggests various therapeutic benefits of terpenes, such as myrcene for relaxation; linalool as a sleep aid and to relieve exhaustion and mental stress; D-limonene as an analgesic; caryophyllene for cold tolerance and analgesia; valencene for cartilage protection; borneol for antinociceptive and anticonvulsant potential; and eucalyptol for muscle pain. While exploratory research suggests terpenes as influencers in the therapeutic benefits of cannabinoids, the potential for synergistic or additive enhancement of cannabinoid efficacy by terpenes remains unproven. Further clinical trials are needed to confirm any terpenes "entourage effects."

Cannabidiol Plays a Modulatory Function on the Methamphetamine-Induced Reward Through Hippocampal D2-Like Dopamine Receptors

Methamphetamine (METH), a stimulant that is extremely addictive, directly affects the central nervous system. METH's abuse and consumption are directly linked to mental illnesses, psychosis, and behavioral and cognitive impairments. It may disrupt the reward system and dopaminergic transmission. METH's rewarding qualities are associated with a rise in dopamine. Additionally, cannabidiol (CBD), one of the primary cannabinoid components of the cannabis plant, significantly affects dopaminergic transmission and may aid in reward- and addiction-related behaviors. To shed light on the role of the D2-like dopamine receptor (D2R) in the hippocampal dentate gyrus (DG), the present study examined the effects of CBD on the acquisition and expression of the conditioned place preference (CPP) induced by METH. The function of D2R was ascertained by delivering Sulpiride microinjections, as a D2R antagonist Sulpiride (0.25, 1, and 4 μg/0.5 μL DMSO12%) into the DG. Moreover, an intracerebroventricular injection of CBD at a dose of 10 μg/5 μL for CPP acquisition and 50 μg/5 μL for CPP expression was given to rats. According to the current research, CBD dramatically reduced the acquisition and expression of CPP resulting from METH. However, Sulpiride suppressed the effect of CBD on METH-induced CPP acquisition and expression, with a greater impact on expression experiments. Ultimately, this study proposed that the expression experiment of METH-induced CPP appears to be heavily dependent on D2R in the DG.

Physiological profiling of cannabidiol reveals profound inhibition of sensory neurons

ABSTRACT

Cannabidiol (CBD), the main nonpsychoactive cannabinoid of cannabis, holds promise for nonaddictive treatment of pain. Although preclinical studies have been encouraging, well-controlled human trials have been largely unsuccessful. To investigate this dichotomy and better understand the actions of CBD, we used high-content calcium imaging with automated liquid handling and observed broad inhibition of neuronal activation by a host of ionotropic and metabotropic receptors, including transient receptor potential (Trp) and purinergic receptors, as well as mediators of intracellular calcium cycling. To assess the effect of CBD on overall nociceptor electrical activity, we combined the light-activated ion channel channelrhodposin in TRPV1-positive nociceptors and a red-shifted calcium indicator and found that 1 µM CBD profoundly increased the optical threshold for calcium flux activation. Experiments using traditional whole-cell patch-clamp showed increase of nociceptor activation threshold at submicromolar concentrations, but with unusually slow kinetics, as well as block of voltage-activated currents. To address a more integrated capacity of CBD to influence nociceptor sensitization, a process implicated in multiple pain states, we found that submicromolar concentrations of CBD inhibited sensitization by the chemotherapeutic drug vincristine. Taken together, these results demonstrate that CBD can reduce neuronal activity evoked by a strikingly wide range of stimuli implicated in pain signaling. The extensive effects underscore the need for further studies at substantially lower drug concentrations, which are more likely to reflect physiologically relevant mechanisms. The slow kinetics and block raise biophysical questions regarding the lipophilic properties of CBD and its action on channels and receptors within membranes.