Anticonvulsant effect of cannabidiol in the pentylenetetrazole model: Pharmacological mechanisms, electroencephalographic profile, and brain cytokine levels.

Posted on August 19, 2017 by David

“Cannabidiol (CBD), the main nonpsychotomimetic compound from Cannabis sativa, inhibits experimental seizures in animal models and alleviates certain types of intractable epilepsies in patients.

Here we tested the hypothesis that CBD anticonvulsant mechanisms are prevented by cannabinoid (CB₁ and CB₂) and vanilloid (TRPV1) receptor blockers. We also investigated its effects on electroencephalographic (EEG) activity and hippocampal cytokines in the pentylenetetrazole (PTZ) model.

Pretreatment with CBD (60mg/kg) attenuated seizures induced by intraperitoneal, subcutaneous, and intravenous PTZ administration in mice. The effects were reversed by CB₁, CB₂, and TRPV1 selective antagonists (AM251, AM630, and SB366791, respectively). Additionally, CBD delayed seizure sensitization resulting from repeated PTZ administration (kindling). This cannabinoid also prevented PTZ-induced EEG activity and interleukin-6 increase in prefrontal cortex.

In conclusion, the robust anticonvulsant effects of CBD may result from multiple pharmacological mechanisms, including facilitation of endocannabinoid signaling and TRPV1 mechanisms. These findings advance our understanding on CBD inhibition of seizures, EEG activity, and cytokine actions, with potential implications for the development of new treatments for certain epileptic syndromes.”

https://www.ncbi.nlm.nih.gov/pubmed/28821005

http://www.epilepsybehavior.com/article/S1525-5050(17)30322-0/fulltext

Could Cannabidiol be a Treatment Option for Intractable Childhood and Adolescent Epilepsy?

Posted on August 5, 2017 by David

“Epilepsy is an important disease that affects brain function, particularly in those under 3 years old. Uncontrolled seizures can affect cognitive function and quality of life. For these reasons, many trials have been conducted to investigate treatments for pediatric epilepsy. Currently, many antiepileptic drugs are available for the treatment of epilepsy, but cases of intractable epilepsy continue to exist.

In the past, cannabis has been tested as a potential treatment of intractable epilepsy.

Since 2013, 10 epilepsy centers in America have conducted research regarding the efficacy of cannabis to treat epilepsy. Cannabis has many components, including cannabidiol (CBD) and Δ⁹-tetrahydrocannabinol (THC). THC has psychoactive properties exerted through its binding of the cannabinoid receptor (CBR) whereas CBD is a CBR antagonist. The inhibition of epilepsy by CBD may therefore be caused by various mechanisms, although the detailed mechanisms of CBD actions have not yet been well defined. In most studies, trial doses of CBD were 2-5 mg/kg/day.

Several such studies have shown that CBD does have efficacy for treatment of epilepsy.

Reported adverse effects of CBD were mostly mild, including drowsiness, diarrhea, and decreased appetite. Severe adverse reactions requiring treatment, such as status epilepticus, have also been reported but it is not clear that this is related to CBD. Furthermore, many previous studies have been limited by an open-label or survey design. In future, double-blind, controlled trials are required and the use of CBD to treat other neurological problems should also be investigated.” https://www.ncbi.nlm.nih.gov/pubmed/28775950

“Most studies suggest anticonvulsant effects of CBD, and consider most adverse effects to be mild. It must be borne in mind that CBD is still illegal in many contexts. However, it has the potential to treat various neurological problems, including epilepsy.” http://www.j-epilepsy.org/journal/view.php?doi=10.14581/jer.17003

Anticonvulsant effect of cannabinoid receptor agonists in models of seizures in developing rats.

Posted on July 12, 2017 by David

Epilepsia

“Although drugs targeting the cannabinoid system (e.g., CB1 receptor agonists) display anticonvulsant efficacy in adult animal models of seizures/epilepsy, they remain unexplored in developing animal models. However, cannabinoid system functions emerge early in development, providing a rationale for targeting this system in neonates.

We examined the therapeutic potential of drugs targeting the cannabinoid system in three seizure models in developing rats.

The mixed CB1/2 agonist and the CB1-specific agonist, but no other drugs, displayed anticonvulsant effects against clonic seizures in the DMCM model. By contrast, both CB1 and CB2 antagonism increased seizure severity. Similarly, we found that the CB1/2 agonist displayed antiseizure efficacy against acute hypoxia-induced seizures (automatisms, clonic and tonic-clonic seizures) and tonic-clonic seizures evoked by PTZ.

Early life seizures represent a significant cause of morbidity, with 30-40% of infants and children with epilepsy failing to achieve seizure remission with current pharmacotherapy. Identification of new therapies for neonatal/infantile epilepsy syndromes is thus of high priority.

These data indicate that the anticonvulsant action of the CB system is specific to CB1 receptor activation during early development and provide justification for further examination of CB1 receptor agonists as novel antiepileptic drugs targeting epilepsy in infants and children.” https://www.ncbi.nlm.nih.gov/pubmed/28691158

http://onlinelibrary.wiley.com/doi/10.1111/epi.13842/abstract

Assessing the role of serotonergic receptors in cannabidiol’s anticonvulsant efficacy.

Posted on June 19, 2017 by David

“Cannabidiol (CBD) is a phytocannabinoid that has demonstrated anticonvulsant efficacy in several animal models of seizure. The current experiment validated CBD’s anticonvulsant effect using the acute pentylenetetrazol (PTZ) model.

While this work further confirms the anticonvulsant efficacy of CBD and supports its application in the treatment of human seizure disorders, additional research on CBD’s mechanism of action must be conducted.”

https://www.ncbi.nlm.nih.gov/pubmed/28624721

http://www.epilepsybehavior.com/article/S1525-5050(17)30122-1/fulltext

Cannabidiol Treatment for Refractory Seizures in Sturge-Weber Syndrome.

Posted on April 30, 2017 by David

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“Sturge-Weber syndrome results in leptomeningeal vascular malformations, medically refractory epilepsy, stroke(s), and cognitive impairments. Cannabidiol, a cannabinoid without psychoactive properties, has been demonstrated in preclinical models to possibly have anticonvulsant, antioxidant, and neuroprotective actions.

CONCLUSION:

This study suggests that cannabidiol may be well tolerated as adjunctive medication for seizure management and provides initial data supporting further study of cannabidiol in individuals with Sturge-Weber syndrome.”

https://www.ncbi.nlm.nih.gov/pubmed/28454984

Protective Effects of Cannabidiol against Seizures and Neuronal Death in a Rat Model of Mesial Temporal Lobe Epilepsy.

Posted on April 4, 2017 by David

“The present study reports the behavioral, electrophysiological, and neuropathological effects of cannabidiol (CBD), a major non-psychotropic constituent of Cannabis sativa, in the intrahippocampal pilocarpine-induced status epilepticus (SE) rat model. Our findings demonstrate anticonvulsant and neuroprotective effects of CBD preventive treatment in the intrahippocampal pilocarpine epilepsy model, either as single or multiple administrations, reinforcing the potential role of CBD in the treatment of epileptic disorders.” https://www.ncbi.nlm.nih.gov/pubmed/28367124

“This study showed that CBD treatment reduces the behavioral severity and oscillatory electrographic changes of SE, the post-ictal lethargy, and the neuronal loss associated with the pilocarpine-induced SE rat model. More studies are needed to understand the specific mechanisms of action related to the neuroprotective and anticonvulsant effects of CBD in epilepsy.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5355474/

The Direct Actions of Cannabidiol and 2-Arachidonoyl Glycerol at GABAA Receptors.

Posted on March 3, 2017 by David

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“Cannabidiol (CBD) is a major non-intoxicating component of cannabis and possesses anti-epileptic, anxiolytic and anti-hyperalgesic properties.

Despite evidence that some endogenous and synthetic cannabinoids interact with GABA_A receptors, no-one has yet investigated the effects of CBD.

Here we used two-electrode voltage clamp electrophysiology to compare the actions of CBD with those of the major central endocannabinoid, 2-arachidonoyl glycerol (2-AG) on human recombinant GABA_A receptors (synaptic α1-6βg2 and extrasynaptic α4β2δ) expressed on Xenopus oocytes.

Taken together these results reveal a mode of action of CBD on specifically configured GABA_A receptors that may be relevant to the anticonvulsant and anxiolytic effects of the compound.”

https://www.ncbi.nlm.nih.gov/pubmed/28249817

Cannabidiol Prevents Cerebral Infarction Via a Serotonergic 5-Hydroxytryptamine1A Receptor–Dependent Mechanism

Posted on February 23, 2017 by David

Image result for stroke journal

“Cannabis contains ≈80 different cannabinoids, including the psychoactive component Δ⁹-tetrahydrocannabinol, and nonpsychoactive components, which include cannabidiol, cannabinol, and cannabigerol.

In those components, cannabidiol, a nonpsychoactive constituent of cannabis, was found to be an anticonvulsant in animal models of epilepsy and in humans with epilepsy. Moreover, cannabidiol has been shown to have antispasmodic, anxiolytic, antinausea, and antirheumatoid arthritic properties. In addition, cannabidiol has been shown to be protective against global and focal ischemic injury.

Cannabidiol has been reported to be a neuroprotectant, but the neuroprotective mechanism of cannabidiol remains unclear. We studied the neuroprotective mechanism of cannabidiol in 4-hour middle cerebral artery (MCA) occlusion mice.

Cannabidiol significantly reduced the infarct volume induced by MCA occlusion in a bell-shaped curve. Similarly, abnormal cannabidiol but not anandamide or methanandamide reduced the infarct volume.

Cannabidiol and abnormal cannabidiol reduced the infarct volume.

These results suggested that the neuroprotective effect of cannabidiol may be related to the increase in CBF through the serotonergic 5-HT_1A receptor.”

http://stroke.ahajournals.org/content/36/5/1071

http://www.thctotalhealthcare.com/category/stroke-2/

Pharmacology of cannabinoids in the treatment of epilepsy.

Posted on January 15, 2017 by David

Image result for Epilepsy Behav

“The use of cannabis products in the treatment of epilepsy has long been of interest to researchers and clinicians alike; however, until recently very little published data were available to support its use.

This article summarizes the available scientific data of pharmacology from human and animal studies on the major cannabinoids which have been of interest in the treatment of epilepsy, including ∆9-tetrahydrocannabinol (∆9-THC), cannabidiol (CBD), ∆9-tetrahydrocannabivarin (∆9-THCV), cannabidivarin (CBDV), and ∆9-tetrahydrocannabinolic acid (Δ9-THCA).

It has long been known that ∆9-THC has partial agonist activity at the endocannabinoid receptors CB1 and CB2, though it also binds to other targets which may modulate neuronal excitability and neuroinflammation.

The actions of Δ9-THCV and Δ9-THCA are less well understood. In contrast to ∆9-THC, CBD has low affinity for CB1 and CB2 receptors and other targets have been investigated to explain its anticonvulsant properties including TRPV1, voltage gated potassium and sodium channels, and GPR55, among others.

We describe the absorption, distribution, metabolism, and excretion of each of the above mentioned compounds. Cannabinoids as a whole are very lipophilic, resulting in decreased bioavailability, which presents challenges in optimal drug delivery. Finally, we discuss the limited drug-drug interaction data available on THC and CBD.

As cannabinoids and cannabis-based products are studied for efficacy as anticonvulsants, more investigation is needed regarding the specific targets of action, optimal drug delivery, and potential drug-drug interactions.”

https://www.ncbi.nlm.nih.gov/pubmed/28087250

Cannabidiol Mellows Out Resurgent Sodium Current

Posted on November 22, 2016 by David

“Cannabidiol has received abundant media attention as a potential therapy for intractable epilepsy, based mainly on anecdotal evidence.

These findings suggest that cannabidiol could be exerting its anticonvulsant effects, at least in part, through its actions on voltage-gated sodium channels, and resurgent current may be a promising therapeutic target for the treatment of epilepsy syndromes.”

http://www.epilepsycurrents.org/doi/full/10.5698/1535-7511-16.6.399