“The discovery of endocannabinoid’s role within the central nervous system and its potential therapeutic benefits have brought forth rising interest in the use of cannabis for medical purposes. The present review aimed to synthesize and evaluate the available evidences on the efficacy of cannabis and its derivatives for psychiatric, neurodegenerative and movement disorders. A systematic search of randomized controlled trials of cannabis and its derivatives were conducted via databases (PubMed, Embase and the Cochrane Central Register of Controlled Trials). A total of 24 reports that evaluated the use of medical cannabis for Alzheimer’s disease, anorexia nervosa, anxiety, dementia, dystonia, Huntington’s disease, Parkinson’s disease, post-traumatic stress disorder (PTSD), psychosis and Tourette syndrome were included in this review. Trial quality was assessed with the Cochrane risk of bias tool. There is a lack of evidence on the therapeutic effects of cannabinoids for amyotrophic lateral sclerosis and dystonia. Although trials with positive findings were identified for anorexia nervosa, anxiety, PTSD, psychotic symptoms, agitation in Alzheimer’s disease and dementia, Huntington’s disease, and Tourette syndrome, and dyskinesia in Parkinson’s disease, definitive conclusion on its efficacy could not be drawn. Evaluation of these low-quality trials, as rated on the Cochrane risk of bias tools, was challenged by methodological issues such as inadequate description of allocation concealment, blinding and underpowered sample size. More adequately powered controlled trials that examine the long and short term efficacy, safety and tolerability of cannabis for medical use, and the mechanisms underpinning the therapeutic potential are warranted.”
“The use of medical cannabis (MC) is controversial. Support for its benefits is based on small clinical series.
The aim of this study was to report the results of a standardized interview study that retrospectively assessed the effects of MC on symptoms of Parkinson disease (PD) and its adverse effects in patients treated for at least 3 months.
The survey used telephone interviews using a structured questionnaire based on subjective global impressions of change for various parkinsonian symptoms and yes/no questions on adverse effects.
Forty-seven nondemented patients with PD (40 men) participated. Their mean age was 64.2 ± 10.8 years, mean disease duration was 10.8 ± 8.3 years, median Hoehn and Yahr (H&Y) was stage III. The duration of MC use was 19.1 ± 17.0 months, and the mean daily dose was 0.9 ± 0.5 g. The delivery of MC was mainly by smoking cigarettes (38 cases, 80.9%). Effect size (r) improvement for falls was 0.89, 0.73 for pain relief, 0.64 for depression, 0.64 for tremor, 0.62 for muscle stiffness, and 0.60 for sleep. The most frequently reported adverse effects from MC were cough (34.9%) in those who used MC by smoking and confusion and hallucinations (reported by 17% each) causing 5 patients (10.6%) to stop treatment.
Medical cannabis was found to improve symptoms of PD in the initial stages of treatment and did not cause major adverse effects in this pilot, 2-center, retrospective survey. The extent of use and the reported effects lend support to further development of safer and more effective drugs derived from Cannabis sativa.”
“The main pathological feature of Parkinson’s disease (PD) is the loss of dopaminergic neurons in the substantia nigra. In this study, we investigated the role of cannabinoid receptor 2 (CB2R) agonist AM1241 on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in a mouse model of PD.
Upon treatment with AM1241, the decreased CB2R level in the PD mouse brain was reversed and the behavior score markedly elevated, accompanied with a dose-dependent increase of dopamine and serotonin. In addition, western blot assay and immunostaining results suggested that AM1241 significantly activated PI3K/Akt/MEK phosphorylation and increased the expression of Parkin and PINK1, both in the substantia nigra and hippocampus. The mRNA expression analysis further demonstrated that AM1241 increased expression of the CB2R and activated Parkin/PINK1 signaling pathways. Furthermore, the increased number of TH-positive cells in the substantia nigra indicated that AM1241 regenerated DA neurons in PD mice, and could therefore be a potential candidate for PD treatment. The clear co-localization of CB2R and DA neurons suggested that AM1241 targeted CB2R, thus also identifying a novel target for PD treatment.
In conclusion, the selective CB2 agonist AM1241 has a significant therapeutic effect on PD mice and resulted in regeneration of DA neurons following MPTP-induced neurotoxicity. The possible mechanisms underlying the neurogenesis effect of AM1241 might be the induction of CB2R expression and an increase in phosphorylation of the PI3K/AKT signaling pathway.”
“Spasticity is a common neurologic condition in patients with multiple sclerosis, stroke, cerebral palsy or an injured spinal cord. Animal studies suggest that THC has an inhibitory effect on polysynaptic reflexes.
Some spastic patients claim improvement after inhaling cannabis. We tested muscle tone, reflexes, strength and performed EMGs before and after double-blinded oral administration of either 10 or 5 mg THC or placebo.
10 mg THC significantly reduced spasticity by clinical measurement (P less than 0.01).
Responses varied, but benefit was seen in three of three patients with “tonic spasms.””
“The endocannabinoid system plays a regulatory role in a number of physiological processes and has been found altered in different pathological conditions, including movement disorders. The interactions between cannabinoids and dopamine in the basal ganglia are remarkably complex and involve both the modulation of other neurotransmitters (γ-aminobutyric acid, glutamate, opioids, peptides) and the activation of different receptors subtypes (cannabinoid receptor type 1 and 2).
In the last years, experimental studies contributed to enrich this scenario reporting interactions between cannabinoids and other receptor systems (transient receptor potential vanilloid type 1 cation channel, adenosine receptors, 5-hydroxytryptamine receptors). The improved knowledge, adding new interpretation on the biochemical interaction between cannabinoids and other signaling pathways, may contribute to develop new pharmacological strategies.
A number of preclinical studies in different experimental Parkinson’s disease (PD) models demonstrated that modulating the cannabinoid system may be useful to treat some motor symptoms. Despite new cannabinoid-based medicines have been proposed for motor and nonmotor symptoms of PD, so far, results from clinical studies are controversial and inconclusive. Further clinical studies involving larger samples of patients, appropriate molecular targets, and specific clinical outcome measures are needed to clarify the effectiveness of cannabinoid-based therapies.” https://www.ncbi.nlm.nih.gov/pubmed/28861502
“Cannabis is a psychoactive compound widely used along history for recreational and therapeutic purposes. Although many open questions remain, cannabis-based therapies have become increasingly common raising considerable interest in politics as well as in general public for legalization of medical cannabis.” http://online.liebertpub.com/doi/10.1089/can.2017.0002
“Phytocannabinoids are produced in Cannabis sativa L. in acidic form and are decarboxylated upon heating, processing, and storage. While the biological effects of decarboxylated cannabinoids such as Δ9 -tetrahydrocannabinol (Δ9 -THC) have been extensively investigated, the bioactivity of Δ9 -THCA is largely unknown, despite its occurrence in different Cannabis preparations. The aim of this study was to determine whether Δ9 -THCA modulates the PPARγ pathway and has neuroprotective activity.
The effects of six phytocannabinoids on PPARγ binding and transcriptional activity were investigated. The effect of Δ9 -THCA on mitochondrial biogenesis and PGC-1α expression was investigated in N2a cells. The neuroprotective effect was analysed in STHdhQ111/Q111 cells expressing a mutated form of the huntingtin protein, and in N2a cells infected with an adenovirus carrying human huntingtin containing 94 polyQ repeats (mHtt-q94). In vivo neuroprotective activity of Δ9 -THCA was investigated in mice intoxicated with the mitochondrial toxin 3-nitropropionic acid (3-NP).
Cannabinoid acids bind and activate PPARγ with higher potency than their decarboxylated products. Δ9 -THCA increases mitochondrial mass in neuroblastoma N2a cells, and prevents cytotoxicity induced by serum deprivation in STHdhQ111/Q111cells and by mutHtt-q94 in N2a cells. Δ9 -THCA, through a PPARγ-dependent pathway, was neuroprotectant in mice intoxicated with 3-NP, improving motor deficits and preventing striatal degeneration. In addition, Δ9 -THCA attenuated microgliosis, astrogliosis and the upregulation of proinflammatory markers induced by 3-NP.
CONCLUSION AND IMPLICATIONS:
Δ9 -THCA shows potent neuroprotective activity, worth consideration for the treatment of Huntington´s Disease and possibly other neurodegenerative and neuroinflammatory diseases.”
“Endocannabinoids are important regulators of neurotransmission and, acting on activated microglia, they are postulated as neuroprotective agents. Endocannabinoid action is mediated by CB1 and CB2 receptors, which may form heteromeric complexes (CB1-CB2Hets) with unknown function in microglia.
We aimed at establishing the expression and signaling properties of cannabinoidreceptors in resting and LPS/IFN-γ-activated microglia. Unlike CB1, CB2 receptors and CB1-CB2Hets were upregulated in activated microglia. Resting cell refractory CB2 receptors became robustly coupled to Gi in activated cells, in which CB1-CB2Hets mediated a positive cross-talk. Resting cells were refractory while activated cells were highly responsive to cannabinoids. Interestingly, similar results were obtained in cultures treated with ß-amyloid (Aß1-42). Activation microglial markers were detected in the striatum of a Parkinson’s disease (PD) model and, remarkably, in primary microglia cultures from the hippocampus of mutant β-amyloid precursor protein (APPSw,Ind) mice, a transgenic Alzheimer’s disease (AD) model. Also of note was the similar cannabinoid receptor signaling found in primary cultures of microglia from APPSw,Ind and in cells from control animals activated using LPS plus IFN- γ. Expression of CB1-CB2Hets was increased in the striatum from rats rendered dyskinetic by chronic levodopa treatment.
In summary, our results showed sensitivity of activated microglial cells to cannabinoids, increased CB1-CB2Het expression in activated microglia and in microglia from the hippocampus of an AD model, and a correlation between levodopa-induced dyskinesia and striatal microglial activation in a PD model. Cannabinoid receptors and the CB1-CB2 heteroreceptor complex in activated microglia have potential as targets in the treatment of neurodegenerative diseases.”
“The GPR55 receptor is expressed abundantly in the brain, especially in the striatum, suggesting it might fulfill a role in motor function. Indeed, motor behavior is impaired in mice lacking GPR55, which also display dampened inflammatory responses.
Abnormal-cannabidiol (Abn-CBD), a synthetic cannabidiol (CBD) isomer, is a GPR55 agonist that may serve as a therapeutic agent in the treatment of inflammatory diseases.
In this study, we explored whether modulating GPR55 could also represent a therapeutic approach for the treatment of Parkinson’s disease (PD).
These results demonstrate for the first time that activation of GPR55 might be beneficial in combating PD.”
“Cannabis has been used for medicinal purpose for thousands of years; however the positive and negative effects of cannabis use in Parkinson’s disease (PD) and Multiple Sclerosis (MS) are mostly unknown. Our aim was to assess cannabis use in PD and MS and compare results of self-reported assessments of neurological disability between current cannabis users and non-users.
Current users reported high efficacy of cannabis, 6.4 (SD 1.8) on a scale from 0 to 7 and 59% reported reducing prescription medication since beginning cannabis use. Current cannabis users were younger and less likely to be classified as obese. Cannabis users reported lower levels of disability, specifically in domains of mood, memory, and fatigue.
Cannabis may have positive impacts on mood, memory, fatigue, and obesity status in people with PD and MS. Further studies using clinically and longitudinally assessed measurements of these domains are needed to establish if these associations are causal and determine the long-term benefits and consequences of cannabis use in people with PD and MS.”
“The main pathological feature of Parkinson’s disease (PD) is the loss of dopaminergic neurons in the substantia nigra. In this study, we investigated the role of cannabinoid receptor 2 (CB2R) agonist AM1241 on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in a mouse model of PD. Upon treatment with AM1241, the decreased CB2R level in the PD mouse brain was reversed and the behavior score markedly elevated, accompanied with a dose-dependent increase of dopamine and serotonin. In addition, western blot assay and immunostaining results suggested that AM1241 significantly activated PI3K/Akt/MEK phosphorylation and increased the expression of Parkin and PINK1, both in the substantia nigra and hippocampus. The mRNA expression analysis further demonstrated that AM1241 increased expression of the CB2R and activated Parkin/PINK1 signaling pathways. Furthermore, the increased number of TH-positive cells in the substantia nigra indicated that AM1241 regenerated DA neurons in PD mice, and could therefore be a potential candidate for PD treatment. The clear co-localization of CB2R and DA neurons suggested that AM1241 targeted CB2R, thus also identifying a novel target for PD treatment. In conclusion, the selective CB2 agonist AM1241 has a significant therapeutic effect on PD mice and resulted in regeneration of DA neurons following MPTP-induced neurotoxicity. The possible mechanisms underlying the neurogenesis effect of AM1241 might be the induction of CB2R expression and an increase in phosphorylation of the PI3K/AKT signaling pathway.”