Category Archives: Parkinson’s Disease

Marijuana-Like Compounds May Aid Array Of Debiliatiing Conditions Ranging From Parkinson’s Disease To Pain

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“Oct. 27, 2004 — No longer a pipe dream, new animal research now indicates that marijuana-like compounds can aid a bevy of debilitating conditions, ranging from brain disorders such as amyotrophic lateral sclerosis (ALS) and Parkinson’s disease, to pain and obesity.

Research from California Pacific Medical Center in San Francisco points to the promise of marijuana-like treatments for those with the fatal brain disorder ALS, also known as Lou Gehrig’s disease.

“Our research indicates that select marijuana compounds, including THC, significantly slow the disease process and extend the life of mice with ALS,” says study author Mary Abood, PhD.

The study extends earlier work from Abood’s group that found that THC also can alleviate some ALS symptoms, like muscle spasms, in patients.

ALS wreaks its havoc by harming nerve cells that control muscles. As a consequence of the damage, an estimated 5,000 Americans afflicted annually experience progressive muscle weakness that can hinder movement, speech, even swallowing and breathing. New treatments for ALS are desperately needed…

“For the first time, our research shows the neuroprotective value of marijuana-like compounds in a well-established animal model of Parkinson’s disease,” says study author Andrea Giuffrida, PhD, of the University of Texas Health Science Center in San Antonio.

Parkinson’s afflicts some 1 million Americans. Symptoms include slowness of movement, muscle stiffness, and shaky tremors, which can harm a person’s ability to walk, talk, write, and eat. This havoc results from the death or injury of brain cells that produce the chemical dopamine.

“There are therapies that can help replenish depleted levels of dopamine and provide symptomatic relief, but none can reverse, prevent, or delay the progression of Parkinson’s disease,” says Giuffrida. “Our research shows that marijuana-like compounds may be able to answer this need.””

Read more: http://www.sciencedaily.com/releases/2004/10/041027102621.htm

 

Effects of cannabinoids Δ(9)-tetrahydrocannabinol, Δ(9)-tetrahydrocannabinolic acid and cannabidiol in MPP+ affected murine mesencephalic cultures.

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Abstract

“Cannabinoids derived from Cannabis sativa demonstrate neuroprotective properties in various cellular and animal models. Mitochondrial impairment and consecutive oxidative stress appear to be major molecular mechanisms of neurodegeneration. Therefore we studied some major cannabinoids, i.e. delta-9-tetrahydrocannabinolic acid (THCA), delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in mice mesencephalic cultures for their protective capacities against 1-methyl-4-phenyl pyridinium (MPP(+)) toxicity. MPP(+) is an established model compound in the research of parkinsonism that acts as a complex I inhibitor of the mitochondrial respiratory chain, resulting in excessive radical formation and cell degeneration. MPP(+) (10 μM) was administered for 48 h at the 9th DIV with or without concomitant cannabinoid treatment at concentrations ranging from 0.01 to 10 μM. All cannabinoids exhibited in vitro antioxidative action ranging from 669 ± 11.1 (THC), 16 ± 3.2 (THCA) to 356 ± 29.5 (CBD) μg Trolox (a vitamin E derivative)/mg substance in the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay. Cannabinoids were without effect on the morphology of dopaminergic cells stained by tyrosine hydroxylase (TH) immunoreaction. THC caused a dose-dependent increase of cell count up to 17.3% at 10 μM, whereas CBD only had an effect at highest concentrations (decrease of cell count by 10.1-20% at concentrations of 0.01-10 μM). It influenced the viability of the TH immunoreactive neurons significantly, whereas THCA exerts no influence on dopaminergic cell count. Exposure of cultures to 10 μM of MPP(+) for 48 h significantly decreased the number of TH immunoreactive neurons by 44.7%, and shrunken cell bodies and reduced neurite lengths could be observed. Concomitant treatment of cultures with cannabinoids rescued dopaminergic cells. Compared to MPP(+) treated cultures, THC counteracted toxic effects in a dose-dependent manner. THCA and CBD treatment at a concentration of 10 μM lead to significantly increased cell counts to 123% and 117%, respectively. Even though no significant preservation or recovery of neurite outgrowth to control values could be observed, our data show that cannabinoids THC and THCA protect dopaminergic neurons against MPP(+) induced cell death.”

http://www.ncbi.nlm.nih.gov/pubmed/22571976

Therapeutic potential of cannabinoids in the treatment of neuroinflammation associated with Parkinson’s disease.

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Abstract

“The cannabinoid system is represented by two principal receptor subtypes, termed CB1 and CB2, along with several endogenous ligands. In the central nervous system it is involved in several processes. CB1 receptors are mainly expressed by neurons and their activation is primarily implicated in psychotropic and motor effects of cannabinoids. CB2 receptors are expressed by glial cells and are thought to participate in regulation of neuroimmune reactions. This review aims to highlight several reported properties of cannabinoids that could be used to inhibit the adverse neuroinflammatory processes contributing to Parkinson’s disease and possibly other neurodegenerative disorders. These include anti-oxidant properties of phytocannabinoids and synthetic cannabinoids as well as hypothermic and antipyretic effects. However, cannabinoids may also trigger signaling cascades leading to impaired mitochondrial enzyme activity, reduced mitochondrial biogenesis, and increased oxidative stress, all of which could contribute to neurotoxicity. Therefore, further pharmacological studies are needed to allow rational design of new cannabinoid-based drugs lacking detrimental in vivo effects.”

http://www.ncbi.nlm.nih.gov/pubmed/21699489

Cannabidiol for the treatment of psychosis in Parkinson’s disease.

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Abstract

“The management of psychosis in Parkinson’s disease (PD) has been considered a great challenge for clinicians and there is a need for new pharmacological intervention. Previously an antipsychotic and neuroprotective effect of Cannabidiol (CBD) has been suggested. Therefore, the aim of the present study was to directly evaluate for the first time, the efficacy, tolerability and safety of CBD on PD patients with psychotic symptoms. This was an open-label pilot study. Six consecutive outpatients (four men and two women) with the diagnosis of PD and who had psychosis for at least 3 months were selected for the study. All patients received CBD in flexible dose (started with an oral dose of 150 mg/day) for 4 weeks, in addition to their usual therapy. The psychotic symptoms evaluated by the Brief Psychiatric Rating Scale and the Parkinson Psychosis Questionnaire showed a significant decrease under CBD treatment. CBD did not worsen the motor function and decreased the total scores of the Unified Parkinson’s Disease Rating Scale. No adverse effect was observed during the treatment. These preliminary data suggest that CBD may be effective, safe and well tolerated for the treatment of the psychosis in PD.”

http://www.ncbi.nlm.nih.gov/pubmed/18801821

Cannabinoid CB1 antagonists possess antiparkinsonian efficacy only in rats with very severe nigral lesion in experimental parkinsonism.

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Abstract

“We have observed that systemic administration of cannabinoid CB1 antagonists exerts antiparkinsonian effects in rats with very severe nigral lesion (>95% cell loss), but not in rats with less severe lesion (85-95% cell loss). Local injections into denervated striatum and corresponding globus pallidus reduced parkinsonian asymmetry. Infusions into lesioned substantia nigra enhanced motor asymmetries, but this effect was absent after very severe nigral lesion. At the striatal level, CB1 antagonists act enhancing dopamine D1 receptor function and reducing D2 receptor function. Striatal dopaminergic denervation did not affect cannabinoid CB1 receptor coupling to G proteins. These results suggest that (i) systemic administration of CB1 antagonists in rats with severe nigral degeneration is ineffective because striatopallidal-mediated motor effects are antagonized by nigra-mediated activity, and (ii) CB1 antagonists exert antiparkinsonian effects after very severe nigral degeneration because nigra-mediated inhibition disappears. CB1 receptor antagonists that lack psychoactive effects might be of therapeutic value in the control of very advanced stage of Parkinson’s disease in humans.”

http://www.ncbi.nlm.nih.gov/pubmed/15755685

Cannabinoid receptor agonist protects cultured dopaminergic neurons from the death by the proteasomal dysfunction.

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“Cannabinoids (CBs) from the Cannabis sativa L. plant, including tetrahydrocannabinol, the principal psychoactive component of marijuana, produce euphoria and relaxation and also impair motor coordination, perception of time, and short-term memory. The principal actions of CBs are mediated by activation of their cognate receptors on presynaptic nerve ends. Various types of cannabinoid receptors, including the orphan G-protein coupled receptors CB1 and CB2, are found in blood vessels, the central nervous system, and immune cells. While CB1 is expressed abundantly in several areas in the brain as well as in peripheral tissues, CB2 is primarily expressed in the immune system, although it was recently detected at low levels in peripheral nerve endings, microglial cells, and astrocytes, as well as in the cerebellum and brain stem. CB1 receptor activation is involved in the control of neural cell fate and mediates neuroprotectivity in different in vivo models of brain injury, including excitotoxicity and ischemia.

In recent years, the capacity of CBs to effect neuroprotection and neurotoxicity has received increasing attention. Evidence of possible neuroprotective effects has accumulated in vitro from models of neurodegenerative diseases, including Alzheimer’s and Parkinson’s diseases and multiple sclerosis, as well as from in vivo clinical trial data. These compounds are also able to decrease inflammation by acting on glial cells that influence neuronal survival. The molecular mechanisms underlying cannabinoid-mediated neuroprotection are still poorly understood, but may include the direct activation of neuronal survival signaling pathways through cannabinoid receptors or indirect effects mediated by microglial CB2-receptor stimulation.

Here, we investigated the neuroprotective function of a synthetic cannabinoid-receptor agonist (WIN55.212.2)… These results indicate that WIN55.212.2 may be a candidate for treatment of neurodegenerative diseases, including Parkinson’s disease.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145842/

Latest advances in cannabinoid receptor agonists.

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“Since the discovery of cannabinoid receptors and their endogenous ligands in early 1990s, the endocannabinoid system has been shown to play a vital role in several pathophysiological processes. It has been targeted for the treatment of several diseases including neurodegenerative diseases (Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and MS), cancer, obesity, inflammatory bowel disease, neuropathic and inflammatory pain. The last decade has witnessed remarkable advances in the development of cannabinergic ligands displaying high selectivity and potency towards two subtypes of cannabinoid receptors, namely CB1 and CB2.”

 “…we highlight the latest advances made in the development of cannabinoid agonists and summarize recently disclosed, novel chemical scaffolds as CB-selective agonists…”

 

“CONCLUSIONS:

Our analysis reveals prolific patenting activity mainly in the CB2 selective agonist area. Limiting the BBB penetrability, thereby, leading to peripherally restricted CB1/CB2 agonists and enhancing CB2-selectivity emerge as likely prerequisites for avoidance of adverse central CB1 mediated side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/19939187

Loss of cannabinoid CB1 receptor expression in the 6-hydroxydopamine-induced nigrostriatal terminal lesion model of Parkinson’s disease in the rat.

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Abstract

“The endocannabinoid system is emerging as a potential alternative to the dopaminergic system for the treatment of Parkinson’s disease. Like all emerging targets, validation of this system’s potential for treating human Parkinsonism necessitates testing in animal models of the condition. However, if components of the endocannabinoid system are altered by the induction of a Parkinsonian state in animal models, this could have an impact on the interpretation of such preclinical experiments. This study sought to determine if expression of the CB(1) subtype of cannabinoid receptor is altered in the two most commonly used rat models of Parkinson’s disease. Parkinsonian lesions were induced by stereotaxic injection of 6-hydroxydopamine into the axons (medial forebrain bundle) or terminals (striatum) of the nigrostriatal pathway. On days 1, 3, 7, 14 and 28 post-lesion, rats were sacrificed and brains were processed for tyrosine hydroxylase and CB(1) receptor immunohistochemistry. The CB(1) receptor was expressed strongly in the substantia nigra pars reticulata, minimally overlapping with tyrosine hydroxylase immunoreactivity in the pars compacta. Interestingly, while there was little change in CB(1) receptor expression following axonal lesion, expression of the receptor was significantly reduced following terminal lesion. Loss of CB(1) receptor expression in the pars reticulata correlated significantly with the loss of striatal and nigral volume after terminal lesion indicating this may have been due to 6-hydroxydopamine-induced non-specific damage of striatonigral neurons which are known to express CB(1) receptors. Thus, this result has implications for the choice of model and interpretation of studies used to investigate potential cannabinoid-based therapies for Parkinson’s disease as well as striatonigral diseases such as Huntington’s disease and Multiple Systems Atrophy.”

http://www.ncbi.nlm.nih.gov/pubmed/20097273

CB1 cannabinoid receptor signalling in Parkinson’s disease.

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Abstract

“Signalling at CB(1) cannabinoid receptors plays a key role in the control of movement in health and disease. In recent years, an increased understanding of the physiological role of transmission at CB(1) receptors throughout the basal ganglia circuitry has led to the identification of novel therapeutic approaches to both the symptoms of Parkinson’s disease and the side effects of current anti-parkinsonian therapies, especially L(3,4) dihydroxyphenylalamine (levodopa)-induced dyskinesia. Thus, because activation of basal ganglia CB(1) receptors can modulate neurotransmission and contribute to synaptic plasticity in a manner similar to that described in other brain regions, it also appears that endocannabinoids might modulate cell-cell signalling via effects on neurotransmitter re-uptake and postsynaptic actions mediating cross talk between multiple receptor types. Recent studies in animal models and in the clinic suggest that CB(1) receptor antagonists could prove useful in the treatment of parkinsonian symptoms and levodopa-induced dyskinesia, whereas CB(1) receptor agonists could have value in reducing levodopa-induced dyskinesia.”

http://www.ncbi.nlm.nih.gov/pubmed/12550742

Depression in Parkinson’s disease is related to a genetic polymorphism of the cannabinoid receptor gene (CNR1).

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Abstract

“Depression is a common symptom in Parkinson’s disease (PD) and it is present in up to 40% of the patients. The cause of depression in PD is thought to be related to disturbance of monoamine neurotransmission. The endogenous cannabinoid system mediates different brain processes that play a role in the control of behaviour and emotions. Cannabinoid function may be altered in neuropsychiatry diseases, directly or through interactions with monoamine, GABA and glutamate systems. For this reason, we have investigated whether there is a genetic risk factor for depression in PD linked to the polymorphisms of CB1 receptor gene. Depression was more frequent in patients with PD than in controls with osteoarthritis. The presence of depression did not correlate with the stage of the disease but it was more frequent in patients with pure akinetic syndrome than in those with tremoric or mixed type PD. The CB1 receptor gene polymorphism (AAT)n is considered to modify the transcription of the gene and, therefore, it may have functional relevance. We analysed the length of the polymorphic triplet (AAT)n of the gene that encodes CB1 (CNR1) receptor in 89 subjects (48 PD patients and 41 controls). In patients with PD, the presence of two long alleles, with more than 16 repeated AAT trinucleotides in the CNR1 gene, was associated with a reduced prevalence of depression (Fisher’s exact test: P=0.003). This association did not reach significant differences in the control group, but the number of control individuals with depression was too small to allow for statistical analysis. Since the alleles with long expansions may have functional impact in cannabinoid neurotransmission, our data suggest that the pharmacological manipulation of cannabinoid neurotransmission could open a new therapeutic approach for the treatment of depression in PD and possibly in other conditions.”

http://www.ncbi.nlm.nih.gov/pubmed/15668727