Investigation of cannabidiol’s potential targets in limbic seizures. In-silico approach

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“Even though the vast armamentarium of FDA-approved antiepileptic drugs is currently available, over one-third of patients do not respond to medication, which arises a need for alternative medicine. In clinical and preclinical studies, various investigations have shown the advantage of specific plant-based cannabidiol (CBD) products in treating certain groups of people with limbic epilepsy who have failed to respond to conventional therapies. This work aims to investigate possible mechanisms by which CBD possesses its anticonvulsant properties. Molecular targets for CBD’s treatment of limbic epilepsy, including hyperpolarization-activated cyclic nucleotide-gated channel 1 (HCN1), gamma-aminobutyric acid aminotransferase (GABA-AT), and gamma-aminobutyric acid type A receptor (GABAA), were used to evaluate its binding affinity. Interactions with the CB1 receptor were initially modeled as a benchmark, which further proved the efficiency of proposed here approach. Considering the successful benchmark, we further used the same concept for in silico investigation, targeting proteins of interest. As a result of molecular docking, molecular mechanics, and molecular dynamics simulations models of CBD-receptor complexes were proposed and evaluated. While CBD possessed decently high affinity and stability within the binding pockets of GABA-AT and some binding sites of GABAA, the most effective binding was observed in the CBD complex with HCN1 receptor. 100 ns molecular dynamics simulation revealed that CBD binds the open pore of HCN1 receptor, forming a similar pattern of interactions as potent Lamotrigine. Therefore, we can propose that HCN1 can serve as a most potent target for cannabinoid antiepileptic treatment. Communicated by Ramaswamy H. Sarma.”

https://pubmed.ncbi.nlm.nih.gov/36129109/

https://www.tandfonline.com/doi/abs/10.1080/07391102.2022.2124454?journalCode=tbsd20

Cannabidiol effect in pentylenetetrazole-induced seizures depends on PI3K

SpringerLink

“Background: The phytocannabinoid cannabidiol (CBD) has previously shown to have anticonvulsant effects in preclinical and clinical studies. Recently, CBD has been approved to treat certain types of drug-resistant epileptic syndromes. However, the underlying mechanism of action remains unclear. The phosphatidylinositol 3-kinase (PI3K) signaling pathway has been proposed to modulate seizures and might be recruited by CBD. Thus, we tested the hypothesis that the anticonvulsant effect of CBD involves PI3K in a seizure model induced by pentylenetetrazole (PTZ).

Methods: We employed pharmacological and genetic approaches to inhibit PI3K and quantified its effects on seizure duration, latency, and number.

Results: PI3K genetic ablation increased the duration and number of seizures. CBD inhibited PTZ-induced seizures in mice. Genetic deletion of PI3K or pretreatment with the selective inhibitor LY294002 prevented CBD effects.

Conclusion: Our data strengthen the hypothesis that the CBD anticonvulsant effect requires the PI3K signaling pathway.”

https://pubmed.ncbi.nlm.nih.gov/36112318/

https://link.springer.com/article/10.1007/s43440-022-00391-y

Effects of Cannabidiol on Adaptive Behavior and Quality of Life in Pediatric Patients With Treatment-Resistant Epilepsy

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“Background and purpose: Data regarding the effects of cannabidiol (CBD) on the quality of life (QOL) are currently inadequate. We assessed the QOL of pediatric patients with epilepsy who were treated with CBD.

Methods: This prospective, open-label study included pediatric and adolescent patients (aged 2-18 years) with Dravet syndrome or Lennox-Gastaut syndrome. Oral CBD was administered at 10 mg/kg/day. The Korean version of the Quality Of Life in Childhood Epilepsy (QOLCE) questionnaire was administered when CBD treatment began and again after 6 months. Adaptive behavior was measured using the Korean versions of the Child Behavior Checklist (K-CBCL) and the second edition of the Vineland Adaptive Behavior Scales (Vineland-II).

Results: This study included 41 patients (11 with Dravet syndrome and 30 with Lennox-Gastaut syndrome), of which 25 were male. The median age was 4.1 years. After 6 months, 26.8% (11/41) of patients experienced a ≥50% reduction in the number of seizures. The total score for the QOLCE questionnaire did not change from baseline to after 6 months of CBD treatment (85.71±39.65 vs. 83.12±48.01, respectively; p=0.630). The score in the motor skills domain of Vineland-II reduced from 48.67±13.43 at baseline to 45.18±14.08 after 6 months of treatment (p=0.005). No other Vineland-II scores and no K-CBCL scores had changed after 6 months of CBD treatment.

Conclusions: CBD is an efficacious antiseizure drug used to treat Dravet syndrome and Lennox-Gastaut syndrome. However, it did not improve the patient QOL in our study, possibly because all of our patients had profound intellectual disabilities.”

https://pubmed.ncbi.nlm.nih.gov/36062772/

https://thejcn.com/DOIx.php?id=10.3988/jcn.2022.18.5.547

The Long-Term Effectiveness and Safety of Cannabidiol-Enriched Oil in Children With Drug-Resistant Epilepsy

Pediatrics | Journal of Pediatric Neurology

“Background: Several retrospective studies on pediatric epilepsy reported positive effects of cannabidiol-enriched artisanal cannabis oil and pure cannabidiol oil on seizure reduction.

Methods: This is a retrospective study of children and adolescents with refractory epilepsy caused by various etiologies who were treated with artisanal cannabis oil during January 2014 to June 2019, with at least one year follow-up.

Results: Of 114 patients, 84 (73.3%) reported some improvement in seizure frequency at some point during treatment. Fifty-one (59%) of the 86 patients who continued treatment for at least one year showed >50% improvement in seizure frequency. Seizure etiology, seizure type, and patients’ age and sex were not found to be associated with the response to cannabidiol-enriched cannabis oil. Side effects were minor, and positive effects beyond seizure reduction were noted.

Conclusions: Artisanal cannabidiol-enriched cannabis may be an effective and safe long-term treatment for refractory epilepsy.”

https://pubmed.ncbi.nlm.nih.gov/36049378/

https://www.pedneur.com/article/S0887-8994(22)00122-9/fulltext

Interacting binding insights and conformational consequences of the differential activity of cannabidiol with two endocannabinoid-activated G-protein-coupled receptors

“Cannabidiol (CBD), the major non-psychoactive phytocannabinoid present in the plant Cannabis sativa, has displayed beneficial pharmacological effects in the treatment of several neurological disorders including, epilepsy, Parkinson’s disease, and Alzheimer’s disease. In particular, CBD is able to modulate different receptors in the endocannabinoid system, some of which belong to the family of G-protein-coupled receptors (GPCRs). Notably, while CBD is able to antagonize some GPCRs in the endocannabinoid system, it also seems to activate others. The details of this dual contrasting functional feature of CBD, that is, displaying antagonistic and (possible) agonistic ligand properties in related receptors, remain unknown. Here, using computational methods, we investigate the interacting determinants of CBD in two closely related endocannabinoid-activated GPCRs, the G-protein-coupled receptor 55 (GPR55) and the cannabinoid type 1 receptor (CB1). While in the former, CBD has been demonstrated to function as an antagonist, the way by which CBD modulates the CB1 receptor remains unclear. Namely, CBD has been suggested to directly trigger receptor’s activation, stabilize CB1 inactive conformations or function as an allosteric modulator. From microsecond-length unbiased molecular dynamics simulations, we found that the presence of the CBD ligand in the GPR55 receptor elicit conformational changes associated with antagonist-bound GPCRs. In contrast, when the GPR55 receptor is simulated in complex with the selective agonist ML186, agonist-like conformations are sampled. These results are in agreement with the proposed modulatory function of each ligand, showing that the computational techniques utilized to characterize the GPR55 complexes correctly differentiate the agonist-bound and antagonist-bound systems. Prompted by these results, we investigated the role of the CBD compound on the CB1 receptor using similar computational approaches. The all-atom MD simulations reveal that CBD induces conformational changes linked with agonist-bound GPCRs. To contextualize the results we looked into the CB1 receptor in complex with a well-established antagonist. In contrast to the CBD/CB1 complex, when the CB1 receptor is simulated in complex with the ligand antagonist AM251, inactive conformations are explored, showing that the computational techniques utilized to characterize the CB1 complexes correctly differentiate the agonist-bound and antagonist-bound systems. In addition, our results suggest a previously unknown sodium-binding site located in the extracellular domain of the CB1 receptor. From our detailed characterization, we found particular interacting loci in the binding sites of the GPR55 and the CB1 receptors that seem to be responsible for the differential functional features of CBD. Our work will pave the way for understanding the CBD pharmacology at a molecular level and aid in harnessing its potential therapeutic use.”

https://pubmed.ncbi.nlm.nih.gov/36016551/

https://www.frontiersin.org/articles/10.3389/fphar.2022.945935/full

Efficacy and safety of cannabidivarin treatment of epilepsy in girls with Rett syndrome: A phase 1 clinical trial

“Objective: Rett syndrome (RTT), commonly caused by methyl-CpG-binding protein 2 (MECP2) pathogenic variants, has many comorbidities. Fifty to ninety percent of children with RTT have epilepsy, which is often drug-resistant. Cannabidivarin (CBDV), a non-hallucinogenic phytocannabinoid, has shown benefit in MECP2 animal models. This phase 1 trial assessed the safety and tolerability of CBDV in female children with RTT and drug-resistant epilepsy, as well as the effect on mean monthly seizure frequency (MMSF), the electroencephalogram (EEG), and non-epilepsy comorbid symptoms.

Methods: Five female children with drug-resistant epilepsy and a pathogenic MECP2 variant were enrolled. Baseline clinical and laboratory assessments, including monthly seizure frequency, were recorded. CBDV oral solution (50 mg/ml) was prescribed and titrated to 10 mg/kg/day. Data collected included pharmacokinetics, seizure type and frequency, adverse events, EEG, and responses to the Rett Syndrome Behaviour Questionnaire and Rett Syndrome Symptom Severity Index, and were compared to baseline data.

Results: All five children reached the maximum CBDV dose of 10 mg/kg/day and had a reduction in MMSF (median = 79% reduction). Three children had MMSF reduction > 75%. This corresponded to an overall reduction in seizure frequency from 32 to 7.2 seizures per month. Ninety-one percent of adverse events were mild or moderate, and none required drug withdrawal. Sixty-two percent were judged to be unrelated to CBDV. Thirty-one percent of adverse events were identified as possibly related, of which nearly all were mild, and the remainder were later assessed as RTT symptoms. Hypersomnolence and drooling were identified as related to CBDV. No serious adverse events reported were related to CBDV. No significant change was noted in EEG or non-epilepsy-related symptoms of RTT.

Significance: A dose of 10 mg/kg/day of CBDV is safe and well tolerated in a pediatric RTT cohort and suggests improved seizure control in children with MECP2-related RTT.”

https://pubmed.ncbi.nlm.nih.gov/35364618/

“This extends current data to confirm tolerability in a pediatric population and to support trials investigating the use of CBDV in other neurodevelopmental conditions associated with drug-resistant epilepsy.”

https://onlinelibrary.wiley.com/doi/10.1111/epi.17247

Medical cannabinoids: a pharmacology-based systematic review and meta-analysis for all relevant medical indications

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“Background: Medical cannabinoids differ in their pharmacology and may have different treatment effects. We aimed to conduct a pharmacology-based systematic review (SR) and meta-analyses of medical cannabinoids for efficacy, retention and adverse events.

Results: In total, 152 RCTs (12,123 participants) were analysed according to the type of the cannabinoid, outcome and comparator used, resulting in 84 comparisons. Significant therapeutic effects of medical cannabinoids show a large variability in the grade of evidence that depends on the type of cannabinoid. CBD has a significant therapeutic effect for epilepsy (SMD – 0.5[CI – 0.62, – 0.38] high grade) and Parkinsonism (- 0.41[CI – 0.75, – 0.08] moderate grade). There is moderate evidence for dronabinol for chronic pain (- 0.31[CI – 0.46, – 0.15]), appetite (- 0.51[CI – 0.87, – 0.15]) and Tourette (- 1.01[CI – 1.58, – 0.44]) and moderate evidence for nabiximols on chronic pain (- 0.25[- 0.37, – 0.14]), spasticity (- 0.36[CI – 0.54, – 0.19]), sleep (- 0.24[CI – 0.35, – 0.14]) and SUDs (- 0.48[CI – 0.92, – 0.04]). All other significant therapeutic effects have either low, very low, or even no grade of evidence. Cannabinoids produce different adverse events, and there is low to moderate grade of evidence for this conclusion depending on the type of cannabinoid.

Conclusions: Cannabinoids are effective therapeutics for several medical indications if their specific pharmacological properties are considered. We suggest that future systematic studies in the cannabinoid field should be based upon their specific pharmacology.”

https://pubmed.ncbi.nlm.nih.gov/35982439/

“Cannabinoids are effective therapeutics for several medical indications if their specific pharmacological properties are considered. We suggest that future systematic studies in the cannabinoid field should be based upon their specific pharmacology.”

https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-022-02459-1

Cannabidiol and epilepsy in Brazil: a current review

SciELO - Wikipedia

“Background: Cannabidiol (CBD) has become a promising therapeutic option in the treatment of epilepsy. Recent studies provide robust evidence that CBD is effective and safe. Limitations in current knowledge and regulatory issues still limit CBD use. CBD use regarding epilepsy types still lacks clear guidelines.

Objective: To critically review the main current pharmacological features and clinical issues regarding CBD use in epilepsy, to provide current regulatory background regarding CBD use in Brazil, and to suggest a practical CBD therapeutic guide in Brazil.

Methods: Non-systematic literature review (up to February 2022) of current concepts of CBD and epilepsy, including the authors’ personal experience.

Results: Five pivotal trials have led to CBD approval as an adjunctive treatment for Dravet and Lennox-Gastaut syndromes, and for the tuberous sclerosis complex. Efficacy of CBD in other drug-resistant epilepsies remains not completely understood. CBD adverse event profile and drug interactions are better understood. CBD is well tolerated. In Brazil, CBD is not classified as a medication, but as a product subject to a distinct regulatory legislation. CBD is still not offered by the National Brazilian health system, but can be purchased in authorized pharmacies or imported under prescription and signed informed consent.

Conclusion: CBD is a recognized novel treatment for epilepsy. Future well-designed studies and public health strategies are needed to offer widespread access to CBD, and to improve the quality of life of people living with epilepsy in Brazil.”

https://pubmed.ncbi.nlm.nih.gov/35976327/

“In conclusion, epilepsy burden, especially medically refractory epilepsy, affects patients and families, particularly for medically refractory epilepsy. CBD offers hope in treating epilepsy. Current evidence demonstrates efficacy and safety in prescribing CBD for Dravet and Lennox-Gastaut syndrome and Tuberous Sclerosis Complex.”

https://www.scielo.br/j/anp/a/Hw3WJKnhvbxvdCqxc9tNDNd/?lang=en

Safety and efficacy of cannabidiol-cannabidiolic acid rich hemp extract in the treatment of refractory epileptic seizures in dogs

Archive of "Frontiers in Veterinary Science". - PMC

“The use of cannabidiol (CBD) in childhood refractory seizures has become a common therapeutic approach for specific seizure disorders in human medicine. Similarly, there is an interest in using CBD, cannabidiolic acid (CBDA) or cannabinoid-rich hemp products in the treatment of idiopathic epilepsy in dogs.

We aimed to examine a small cohort in a pilot investigation using a CBD and CBDA-rich hemp product for the treatment of refractory epileptic seizures in dogs.

Fourteen dogs were examined in a 24-week randomized cross-over study being provided placebo or CBD/CBDA-rich hemp extract treatment at 2 mg/kg orally every 12 h for each 12-week arm of the study. Serum chemistry, complete blood counts, serum anti-seizure medication (ASM) concentrations and epileptic seizure frequency were followed over both arms of the cross-over trial.

Results demonstrated that besides a mild increase in alkaline phosphatase, there were no alterations observed on routine bloodwork at 2, 6, and 12 weeks during either arm of the study.

Epileptic seizure frequency decreased across the population from a mean of 8.0 ± 4.8 during placebo treatment to 5.0 ± 3.6 with CBD/CBDA-rich hemp extract (P = 0.02). In addition, epileptic seizure event days over the 12 weeks of CBD/CBDA-rich hemp treatment were 4.1 ± 3.4, which was significantly different than during the 12 weeks of placebo treatment (5.8 ± 3.1; P =0.02). The number of dogs with a 50% reduction in epileptic activity while on treatment were 6/14, whereas 0/14 had reductions of 50% or greater while on the placebo (P = 0.02).

No differences were observed in serum zonisamide, phenobarbital or bromide concentrations while on the treatment across groups. Adverse events were minimal, but included somnolence (3/14) and transient increases in ataxia (4/14) during CBD/CBDA-rich hemp extract treatment; this was not significantly different from placebo. This further indicates that providing CBD/CBDA-rich hemp extract during refractory epilepsy (only partially responsive to ASM), in conjunction with other ASM appears safe.

Based on this information, the use of 2 mg/kg every 12 h of a CBD/CBDA-rich hemp extract can have benefits in reducing the incidence of epileptic seizures, when used concurrently with other ASMs.”

https://pubmed.ncbi.nlm.nih.gov/35967998/

“Since the 1970’s or earlier, cannabinoids have been found to have anti-epileptic effects in animal seizure models. In conclusion, there appears to be a population of dogs that respond favorably to CBD/CBDA-rich hemp products for epileptic seizure reduction similar to other human, dog and rodent data.”

https://www.frontiersin.org/articles/10.3389/fvets.2022.939966/full

Neuroprotection of Cannabidiol, Its Synthetic Derivatives and Combination Preparations against Microglia-Mediated Neuroinflammation in Neurological Disorders

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“The lack of effective treatment for neurological disorders has encouraged the search for novel therapeutic strategies. Remarkably, neuroinflammation provoked by the activated microglia is emerging as an important therapeutic target for neurological dysfunction in the central nervous system. In the pathological context, the hyperactivation of microglia leads to neuroinflammation through the release of neurotoxic molecules, such as reactive oxygen species, proteinases, proinflammatory cytokines and chemokines.

Cannabidiol (CBD) is a major pharmacologically active phytocannabinoids derived from Cannabis sativa L. CBD has promising therapeutic effects based on mounting clinical and preclinical studies of neurological disorders, such as epilepsy, multiple sclerosis, ischemic brain injuries, neuropathic pain, schizophrenia and Alzheimer’s disease.

A number of preclinical studies suggested that CBD exhibited potent inhibitory effects of neurotoxic molecules and inflammatory modulators, highlighting its remarkable therapeutic potential for the treatment of numerous neurological disorders. However, the molecular mechanisms of action underpinning CBD’s effects on neuroinflammation appear to be complex and are poorly understood.

This review summarises the anti-neuroinflammatory activities of CBD against various neurological disorders with a particular focus on their main molecular mechanisms of action, which were related to the downregulation of NADPH oxidase-mediated ROS, TLR4-NFκB and IFN-β-JAK-STAT pathways. We also illustrate the pharmacological action of CBD’s derivatives focusing on their anti-neuroinflammatory and neuroprotective effects for neurological disorders. We included the studies that demonstrated synergistic enhanced anti-neuroinflammatory activity using CBD and other biomolecules.

The studies that are summarised in the review shed light on the development of CBD, including its derivatives and combination preparations as novel therapeutic options for the prevention and/or treatment of neurological disorders where neuroinflammation plays an important role in the pathological components.”

https://pubmed.ncbi.nlm.nih.gov/35956911/

“Cannabinoids are a group of terpenophenolic compounds derived from the Cannabis sativa L. plant. The preclinical studies summarised in this review supported the therapeutic use of CBD in treating neurological disorders from its action in addressing microglia-mediated neuroinflammation. The findings of this review shed light on the development of CBD and relevant compounds as novel and more advantageous therapeutics to prevent or treat neurological disorders by targeting microglia-mediated neuroinflammation.”

https://www.mdpi.com/1420-3049/27/15/4961/htm