“The endocannabinoid system (ECS), comprising two G protein-coupled receptors (the cannabinoid receptors 1 and 2 [CB1 and CB2] for marijuana’s psychoactive principle ∆(9)-tetrahydrocannabinol [∆(9)-THC]), their endogenous small lipid ligands (namely anandamide [AEA] and 2-arachidonoylglycerol [2-AG], also known as endocannabinoids), and the proteins for endocannabinoid biosynthesis and degradation, has been suggested as a pro-homeostatic and pleiotropic signaling system activated in a time- and tissue-specific way during physiopathological conditions. In the brain activation of this system modulates the release of excitatory and inhibitory neurotransmitters and of cytokines from glial cells. As such, the ECS is strongly involved in neuropsychiatric disorders, particularly in affective disturbances such as anxiety and depression. It has been proposed that synthetic molecules that inhibit endocannabinoid degradation can exploit the selectivity of endocannabinoid action, thus activating cannabinoid receptors only in those tissues where there is perturbed endocannabinoid turnover due to the disorder, and avoiding the potential side effects of direct CB1 and CB2 activation. However, the realization that endocannabinoids, and AEA in particular, also act at other molecular targets, and that these mediators can be deactivated by redundant pathways, has recently led to question the efficacy of such approach, thus opening the way to new multi-target therapeutic strategies, and to the use of non-psychotropic cannabinoids, such as cannabidiol (CBD), which act via several parallel mechanisms, including indirect interactions with the ECS. The state of the art of the possible therapeutic use of endocannabinoid deactivation inhibitors and phytocannabinoids in mood disorders is discussed in this review article.”
Tag Archives: cannabidiol
The anxiolytic effect of cannabidiol on chronically stressed mice depends on hippocampal neurogenesis: involvement of the endocannabinoid system.
“Cannabidiol (CBD), the main non-psychotomimetic component of the plant Cannabis sativa, exerts therapeutically promising effects on human mental health such as inhibition of psychosis, anxiety and depression. However, the mechanistic bases of CBD action are unclear. Here we investigate the potential involvement of hippocampal neurogenesis in the anxiolytic effect of CBD in mice subjected to 14 d chronic unpredictable stress (CUS). Repeated administration of CBD (30 mg/kg i.p., 2 h after each daily stressor) increased hippocampal progenitor proliferation and neurogenesis in wild-type mice. Ganciclovir administration to GFAP-thymidine kinase (GFAP-TK) transgenic mice, which express thymidine kinase in adult neural progenitor cells, abrogated CBD-induced hippocampal neurogenesis. CBD administration prevented the anxiogenic effect of CUS in wild type but not in GFAP-TK mice as evidenced in the novelty suppressed feeding test and the elevated plus maze. This anxiolytic effect of CBD involved the participation of the CB1 cannabinoid receptor, as CBD administration increased hippocampal anandamide levels and administration of the CB1-selective antagonist AM251 prevented CBD actions. Studies conducted with hippocampal progenitor cells in culture showed that CBD promotes progenitor proliferation and cell cycle progression and mimics the proliferative effect of CB1 and CB2 cannabinoid receptor activation. Moreover, antagonists of these two receptors or endocannabinoid depletion by fatty acid amide hydrolase overexpression prevented CBD-induced cell proliferation.
These findings support that the anxiolytic effect of chronic CBD administration in stressed mice depends on its proneurogenic action in the adult hippocampus by facilitating endocannabinoid-mediated signalling.”
Cannabidiol: an overview of some chemical and pharmacological aspects. Part I: chemical aspects.
“Over the last few years considerable attention has focused on cannabidiol (CBD), a major non-psychotropic constituent of Cannabis. In Part I of this review we present a condensed survey of the chemistry of CBD; in Part II, to be published later, we shall discuss the anti-convulsive, anti-anxiety, anti-psychotic, anti-nausea and anti-rheumatoid arthritic properties of CBD. CBD does not bind to the known cannabinoid receptors and its mechanism of action is yet unknown. In Part II we shall also present evidence that it is conceivable that, in part at least, its effects are due to its recently discovered inhibition of anandamide uptake and hydrolysis and to its anti-oxidative effect.”
Cannabidiol enhances consolidation of explicit fear extinction in humans.
“Whilst Cannabidiol (CBD), a non-psychotomimetic cannabinoid, has been shown to enhance extinction learning in rats, its effects on fear memory in humans have not previously been studied. These findings provide the first evidence that CBD can enhance consolidation of extinction learning in humans and suggest that CBD may have potential as an adjunct to extinction-based therapies for anxiety disorders.”
The role of the endocannabinoid system in Alzheimer’s disease: facts and hypotheses.
“Unlike other neuroinflammatory disorders, like Parkinson’s disease, Huntington’s disease and multiple sclerosis, little is still known of the role of the endocannabinoid system in Alzheimer’s disease (AD). This is partly due to the poor availability of animal models that are really relevant to the human disease, and to the complexity of AD as compared to other neurological states. Nevertheless, the available data indicate that endocannabinoids are likely to play in this disorder a role similar to that suggested in other neurodegenerative diseases, that is, to represent an endogenous adaptive response aimed at counteracting both the neurochemical and inflammatory consequences of beta-amyloid-induced tau protein hyperactivity, possibly the most important underlying cause of AD.
Furthermore, plant and synthetic cannabinoids, and particularly the non-psychotropic cannabidiol, might also exert other, non-cannabinoid receptor-mediated protective effects, including, but not limited to, anti-oxidant actions. There is evidence, from in vivo studies on beta-amyloid-induced neurotoxicity, also for a possible causative role of endocannabinoids in the impairment in memory retention, which is typical of AD.
This might open the way to the use of cannabinoid receptor antagonists as therapeutic drugs for the treatment of cognitive deficits in the more advanced phases of this disorder. The scant, but nevertheless important literature on the regulation and role of the endocannabinoid system in AD, and on the potential treatment of this disorder with cannabinoids and endocannabinoid-based drugs, are discussed in this mini-review.”
Cannabidiol affects the expression of genes involved in zinc homeostasis in BV-2 microglial cells.
“Cannabidiol (CBD) has been shown to exhibit anti-inflammatory, antioxidant and neuroprotective properties. Unlike Δ(9)-tetrahydrocannabinol (THC), CBD is devoid of psychotropic effects and has very low affinity for both cannabinoid receptors, CB(1) and CB(2). We have previously reported that CBD and THC have different effects on anti-inflammatory pathways in lipopolysaccharide-stimulated BV-2 microglial cells, in a CB(1)/CB(2) independent manner. Moreover, CBD treatment of BV-2 cells, was found to induce a robust change in the expression of genes related to oxidative stress, glutathione deprivation and inflammation. Many of these genes were shown to be controlled by Nrf2 and ATF4 transcription factors. Using the Illumina MouseRef-8 BeadChip platform, DAVID Bioinformatics and Ingenuity Pathway Analysis, we identified functional sets of genes and networks affected by CBD. A subset of genes was found to be regulated by the metal responsive element (MRE)-binding transcription factor-1 (MTF-1) and is shown to be related to zinc homeostasis. We found that CBD upregulates the expression of the mRNAs for metallothionein 2 (Mt2), N-myc-downstream regulated gene 1 and matrix metalloproteinase 23 as well as of the zinc transporters ZnT1/Slc30a1 and Zip4/Slc39a4 but downregulates the expression of the mRNA for the zinc transporter Zip10/Slc39a10 as well as for the zinc finger protein 472. Among these genes, ZnT1, Mt2 and the zinc transporters ZIPs are known to function together to control the intracellular zinc concentration. These results show that CBD, but much less so THC, affects the expression of genes involved in zinc homeostasis and suggest that the regulation of zinc levels could have an important role through which CBD may exert its antioxidant and anti-inflammatory effects.”
Cannabidiol as an Emergent Therapeutic Strategy for Lessening the Impact of Inflammation on Oxidative Stress
“Growing evidence suggests that the endocannabinoid system, which includes the CB1 and CB2 G protein-coupled receptors and their endogenous lipid ligands, may be an area that is ripe for therapeutic exploitation. In this context, the related nonpsychotropic cannabinoid cannabidiol, which may interact with the endocannabinoid system, but has actions that are distinct, offers promise as a prototype for anti-inflammatory drug development.
This review discusses recent studies suggesting that cannabidiol may have utility in treating a number of human diseases and disorders now known to involve activation of the immune system and associated oxidative stress, as a contributor to their etiology and progression. These include rheumatoid arthritis, types I and II diabetes, atherosclerosis, Alzheimer’s disease, hypertension, the metabolic syndrome, ischemia-reperfusion injury, depression, and neuropathic pain.
Cannabidiol (CBD) is the major nonpsychotropic cannabinoid compound derived from the plant Cannabis sativa, commonly known as marijuana…
Conclusions
Inflammation and oxidative stress are intimately involved in the genesis of many human diseases. Unraveling that relationship therapeutically has proven challenging, in part because inflammation and oxidative stress “feed off” each other. However, CBD would seem to be a promising starting point for further drug development given its anti-oxidant (although relatively modest) and anti-inflammatory actions on immune cells, such as macrophages and microglia. CBD also has the advantage of not having psychotropic side effects. Studies on models of human diseases support the idea that CBD attenuates inflammation far beyond its antioxidant properties, for example, by targeting inflammation-related intracellular signaling events. The details on how CBD targets inflammatory signaling remain to be defined.
The therapeutic utility of CBD is a relatively new area of investigation that portends new discoveries on the interplay between inflammation and oxidative stress, a relationship that underlies tissue and organ damage in many human diseases.”
Cannabidiol: a promising drug for neurodegenerative disorders?
“Neurodegenerative diseases represent, nowadays, one of the main causes of death in the industrialized country. They are characterized by a loss of neurons in particular regions of the nervous system. It is believed that this nerve cell loss underlies the subsequent decline in cognitive and motor function that patients experience in these diseases. A range of mutant genes and environmental toxins have been implicated in the cause of neurodegenerative disorders but the mechanism remains largely unknown. At present, inflammation, a common denominator among the diverse list of neurodegenerative diseases, has been implicated as a critical mechanism that is responsible for the progressive nature of neurodegeneration.
Since, at present, there are few therapies for the wide range of neurodegenerative diseases, scientists are still in search of new therapeutic approaches to the problem. An early contribution of neuroprotective and antiinflammatory strategies for these disorders seems particularly desirable because isolated treatments cannot be effective.
In this contest, marijuana derivatives have attracted special interest, although these compounds have always raised several practical and ethical problems for their potential abuse. Nevertheless, among Cannabis compounds, cannabidiol (CBD), which lacks any unwanted psychotropic effect, may represent a very promising agent with the highest prospect for therapeutic use.”
Israeli Research Shows Cannabidiol May Slow Alzheimer’s Disease
Read more: http://www.israelnationalnews.com/News/News.aspx/125564
Cannabidiol Reduces Aβ-Induced Neuroinflammation and Promotes Hippocampal Neurogenesis through PPARγ Involvement
“CBD blunted neuroinflammation sustained by astrocytes through PPARγ selective activation in vitro and in vivo.
Results from the present study prove the selective involvement of PPARγ in the anti-inflammatory and neuroprotective effects of CBD here observed either in vitro and in vivo. In addition, CBD significantly promoted neurogenesis in Aβ injured rat hippocampi, much expanding its already wide spectrum of beneficial actions exerted in AD models, a non negligible effect, due to its capability to activate PPARγ.
In conclusion, results of the present research demonstrate that CBD may exert protective functions through a PPARγ dependent activation, which leads to a reduction in reactive gliosis and consequently in neurodegeneration. Moreover, in the current experimental conditions this phytocannabinoid appears to stimulate neurogenesis since it increases DCX immunopositive cell proliferation rate in rat DG.
Innovative therapeutic approaches which could significantly improve AD course require new molecules that will be able to have an impact on different pathological pathways, which converge at the progressive neurological decline. CBD has shown a capability to profoundly reduce reactive astrogliosis and to guarantee both direct and indirect neuronal protection in Aβ induced neuroinflammation/neurodegeration. So far, the lack of understanding of the precise molecular mechanism involved in CBD pharmacological actions, has had limited interest and has puzzled investigators.
Currently, findings of the present study throw some light on the issue, and frame CBD as a new PPARγ activator.”