Control of excessive neural circuit excitability and prevention of epileptic seizures by endocannabinoid signaling

“Progress in research on endocannabinoid signaling has greatly advanced our understanding of how it controls neural circuit excitability in health and disease. In general, endocannabinoid signaling at excitatory synapses suppresses seizures by inhibiting glutamate release. In contrast, endocannabinoid signaling promotes seizures by inhibiting GABA release at inhibitory synapses. The physiological distribution of endocannabinoid signaling molecules becomes disrupted with the development of epileptic focus in patients with mesial temporal lobe epilepsy and in animal models of experimentally induced epilepsy. Augmentation of endocannabinoid signaling can promote the development of epileptic focus at initial stages. However, at later stages, increased endocannabinoid signaling delays it and suppresses spontaneous seizures. Thus, the regulation of endocannabinoid signaling at specific synapses that cause hyperexcitability during particular stages of disease development may be effective for treating epilepsy and epileptogenesis.” https://link.springer.com/article/10.1007/s00018-018-2834-8 http://www.x-mol.com/paper/661834]]>

Efficacy of CBD-enriched medical cannabis for treatment of refractory epilepsy in children and adolescents – An observational, longitudinal study.

Cover image volume 40, Issue 5 “The objective of this observational study was to evaluate the efficacy of medical cannabis for the treatment of refractory epilepsy. Fifty-seven patients (age 1-20 years) with epilepsy of various etiologies were treated with Cannabis oil extract (CBD/THC ratio of 20:1) for at least 3 months (Median follow up time-18 months). Forty-Six Patients were included in the efficacy analysis. Average CBD dose was11.4 mg/kg/d. Twenty-six patients (56%) had ≤50% reduction in mean monthly seizure frequency. There was no statistically significant difference in response rate among various epilepsy etiologies, and cannabis strain used. Younger age at treatment onset (<10 years) and higher CBD dose (>11 mg/kg/d) were associated with better response to treatment. Adverse reactions were reported in 46% of patients and were the main reason for treatment cessation. Our results suggest that adding CBD-enriched cannabis extract to the treatment regimen of patients with refractory epilepsy may result in a significant reduction in seizure frequency according to parental reports.”
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