The endocannabinoid system: an emotional buffer in the modulation of memory function.

“Extensive evidence indicates that endocannabinoids modulate cognitive processes in animal models and human subjects. However, the results of endocannabinoid system manipulations on cognition have been contradictory. As for anxiety behavior, a duality has indeed emerged with regard to cannabinoid effects on memory for emotional experiences. Here we summarize findings describing cannabinoid effects on memory acquisition, consolidation, retrieval and extinction. Additionally, we review findings showing how the endocannabinoid system modulates memory function differentially, depending on the level of stress and arousal associated with the experimental context. Based on the evidence reviewed here, we propose that the endocannabinoid system is an emotional buffer that moderates the effects of environmental context and stress on cognitive processes.”

http://www.ncbi.nlm.nih.gov/pubmed/24382324

Endocannabinoids: a unique opportunity to develop multitarget analgesics.

“After 4 millennia of more or less documented history of cannabis use, the identification of cannabinoids, and of Δ(9)-tetrahydrocannabinol in particular, occurred only during the early 1960s, and the cloning of cannabinoid CB1 and CB2 receptors, as well as the discovery of endocannabinoids and their metabolic enzymes, in the 1990s.

Despite this initial relatively slow progress of cannabinoid research, the turn of the century marked an incredible acceleration in discoveries on the “endocannabinoid signaling system,” its role in physiological and pathological conditions, and pain in particular, its pharmacological targeting with selective agonists, antagonists, and inhibitors of metabolism, and its previously unsuspected complexity.

The way researchers look at this system has thus rapidly evolved towards the idea of the “endocannabinoidome,” that is, a complex system including also several endocannabinoid-like mediators and their often redundant metabolic enzymes and “promiscuous” molecular targets.

These peculiar complications of endocannabinoid signaling have not discouraged efforts aiming at its pharmacological manipulation, which, nevertheless, now seems to require the development of multitarget drugs, or the re-visitation of naturally occurring compounds with more than one mechanism of action.

In fact, these molecules, as compared to “magic bullets,” seem to offer the advantage of modulating the “endocannabinoidome” in a safer and more therapeutically efficacious way.

This approach has provided so far promising preclinical results potentially useful for the future efficacious and safe treatment of chronic pain and inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/23623250

The Endocannabinoid System and Sex Steroid Hormone-Dependent Cancers.

“The “endocannabinoid system (ECS)” comprises the endocannabinoids, the enzymes that regulate their synthesis and degradation, the prototypicalcannabinoid receptors (CB1 and CB2), some noncannabinoid receptors, and an, as yet, uncharacterised transport system.

Recent evidence suggests that both cannabinoid receptors are present in sex steroid hormone-dependent cancer tissues and potentially play an important role in those malignancies.

Sex steroid hormones regulate the endocannabinoid system and the endocannabinoids prevent tumour development through putative protective mechanisms that prevent cell growth and migration, suggesting an important role for endocannabinoids in the regulation of sex hormone-dependent tumours and metastasis.

Here, the role of the endocannabinoid system in sex steroid hormone-dependent cancers is described and the potential for novel therapies assessed.”

http://www.ncbi.nlm.nih.gov/pubmed/24369462

Endocannabinoid signalling in neuronal migration.

“The endocannabinoid (eCB) system consists of several endogenous lipids, their target CB1 and CB2 receptors and enzymes responsible for their synthesis and degradation. The most abundant eCB in the central nervous system (CNS), 2-arachidonoyl glycerol (2-AG), triggers a broad range of signalling events by acting on CB1, the most abundant G protein-coupled receptor in the CNS. The eCB system regulates many physiological processes including neurogenesis, axon guidance and synaptic plasticity. Recent studies have highlighted an additional important role for eCB signalling in neuronal migration, which is crucial to achieve the complex architecture and efficient wiring of the CNS. Indeed, eCB signalling controls migration both pre- and post-natally, regulating interneuron positioning in the developing cortex and hippocampus and the polarized motility of stem cell-derived neuroblasts. While these effects may contribute to cognitive deficits associated with cannabis consumption, they also provide potential opportunities for endogenous stem cell-based neuroregenerative strategies.”

http://www.ncbi.nlm.nih.gov/pubmed/24361301

The cannabinoid receptor type 2 as mediator of mesenchymal stromal cell immunosuppressive properties.

“Recently, the presence of the endocannabinoid system in hematopoietic and neural stem cells has been demonstrated…

In the present study, we have investigated, through a multidisciplinary approach, the involvement of the endocannabinoids in migration, viability and cytokine release of human mesenchymal stromal cells.

We show, for the first time, that cultures of human mesenchymal stromal cells express all of the components of the endocannabinoid system, suggesting a potential role for the cannabinoid CB2 receptor as a mediator of anti-inflammatory properties of human mesenchymal stromal cells, as well as of their survival pathways and their capability to home and migrate towards endocannabinoid sources.”

http://www.ncbi.nlm.nih.gov/pubmed/24312195

Parkinson’s Symptoms Reduced by Smoking Cannabis – Parkinson Research Foundation

Cannabis_Clones_in_Box

 “Ruth Djaldetti, M.D., of Tel Aviv University in Israel, presented the findings of her research at a recent International Congress on Parkinson’s Disease and Movement Disorders.  She reported improvement in tremor, pain, rigidity and bradykinesia (slowness of movement).  Twenty subjects, all in their mid-sixties, and were rated using the Unified Parkinson’s Disease Rating Scale (UPDRS) both before and after smoking.  Their overall “before” scores were over 30 and within 30 minutes of smoking, their scores dropped to 24..  Their tremor scores averaged 7.5 on the UPDRS before and dropped to a score of 3.5 after smoking cannabis.  Bradykinesia scores dropped from 13.2 to 8.6 and rigidity went from 7.4 to 6.4.  Dr. Djaldetti also saw a marked relief in the pain her subjects were experiencing and this relief of pain led to better sleep and feeling more rested.

This bears out the results of other studies.  A study done in Great Britain that was published in 2011 found the principal ingredient in cannabis provided neuroprotection for people with Parkinson’s disease.  Its neuroprotective properties included reduction of inflammation and control of spasms, making it an ideal drug for treating Parkinson’s.  However, its confusing legal status make it very difficult for people to obtain or consider using and for doctors to even recommend to patients.

Another interesting study done in 2010 found that cannabinoid receptors are located in many parts of the brain and that cannabinoids are produced naturally in the brain.  People with Parkinson’s have even higher levels of endocannabinoids (cannabinoids produced within the brain).  The main ingredient in cannabis, Tetrahydrcannibol (THC) actually increases dopamine production temporarily.  Cannabidiol (CBD) another component of cannabis, also provides neuroprotective properties and has been shown to reduce dystonias .  CDB could be a very vital improvement for treating Parkinson’s, and a recent study has shown it useful in treating certain cancers as well.

While there have been many, many people reporting the anecdotal benefits of smoking cannabis, clinical trials are lagging behind.  Laboratory and animal studies have shown many benefits, but perplexing issues around the legality of cannabis are slowing the efforts and impeding progress.”

http://parkinsonresearchfoundation.org/blog/2013/07/11/parkinsons-symptoms-reduced-by-smoking-cannabis/

More surprises lying ahead. The endocannabinoids keep us guessing.

“The objective of this review is to point out some important facts that we don’t know about endogenous cannabinoids – lipid-derived signaling molecules that activate CB1 cannabinoid receptors and play key roles in motivation, emotion and energy balance. The first endocannabinoid substance to be discovered, anandamide, was isolated from brain tissue in 1992. Research has shown that this molecule is a bona fide brain neurotransmitter involved in the regulation of stress responses and pain, but the molecular mechanisms that govern its formation and the neural pathways in which it is employed are still unknown. There is a general consensus that enzyme-mediated cleavage, catalyzed by fatty acid amide hydrolase (FAAH), terminates the biological actions of anandamide, but there are many reasons to believe that other as-yet-unidentified proteins are also involved in this process. We have made significant headway in understanding the second arrived in the endocannabinoid family, 2-arachidonoyl-sn-glycerol (2-AG), which was discovered three years after anandamide. Researchers have established some of the key molecular players involved in 2-AG formation and deactivation, localized them to specific synaptic components, and showed that their assembly into a multi-molecular protein complex (termed the ‘2-AG signalosome’) allows 2-AG to act as a retrograde messenger at excitatory synapses of the brain. Basic questions that remain to be answered pertain to the exact molecular composition of the 2-AG signalosome, its regulation by neural activity and its potential role in the actions of drugs of abuse such as Δ9-THC and cocaine.”

http://www.ncbi.nlm.nih.gov/pubmed/23954677

Evaluation of the role of striatal cannabinoid CB1 receptors on movement activity of parkinsonian rats induced by reserpine.

“It has been observed cannabinoid CB1 receptor signalling and the levels of endocannabinoid ligands significantly increased in the basal ganglia and cerebrospinal fluids of Parkinson’s disease (PD) patients. These evidences suggest that the blocking of cannabinoid CB1 receptors might be beneficial to improve movement disorders as a sign of PD…

 These results support this theory that cannabinoid CB1 receptor antagonists might be useful to alleviate movement disorder in PD…”

http://www.ncbi.nlm.nih.gov/pubmed/23960729

Cannabinoid Receptor CB2 Modulates Axon Guidance.

“Navigation of retinal projections towards their targets is regulated by guidance molecules and growth cone transduction mechanisms. Here, we present in vitro and in vivo evidences that the cannabinoid receptor 2 (CB2R) is expressed along the retino-thalamic pathway and exerts a modulatory action on axon guidance….

Overall, this study demonstrates that the contribution of endocannabinoids to brain development is not solely mediated by CB1R, but also involves CB2R.”

http://www.ncbi.nlm.nih.gov/pubmed/23951024

Anandamide deficiency and heightened neuropathic pain in aged mice.

“Damaging of peripheral nerves may result in chronic neuropathic pain for which the likelihood is increased in the elderly. We assessed in mice if age-dependent alterations of endocannabinoids contributed to the heightened vulnerability to neuropathic pain at old age.

We assessed nociception, endocannabinoids and the therapeutic efficacy of R-flurbiprofen in young and aged mice in the spared nerve injury model of neuropathic pain.

 R-flurbiprofen was used because it is able to reduce neuropathic pain in young mice in part by increasing anandamide.

Aged mice developed stronger nociceptive hypersensitivity after sciatic nerve injury than young mice.

This was associated with low anandamide levels in the dorsal root ganglia, spinal cord, thalamus and cortex, which further decreased after nerve injury…”

 More: http://www.ncbi.nlm.nih.gov/pubmed/23597506