Clinical endocannabinoid deficiency (CECD): can this concept explain therapeutic benefits of cannabis in migraine, fibromyalgia, irritable bowel syndrome and other treatment-resistant conditions?

Abstract

“OBJECTIVES:

This study examines the concept of clinical endocannabinoid deficiency (CECD), and the prospect that it could underlie the pathophysiology of migraine, fibromyalgia, irritable bowel syndrome, and other functional conditions alleviated by clinical cannabis.

METHODS:

Available literature was reviewed, and literature searches pursued via the National Library of Medicine database and other resources.

RESULTS:

Migraine has numerous relationships to endocannabinoid function. Anandamide (AEA) potentiates 5-HT1A and inhibits 5-HT2A receptors supporting therapeutic efficacy in acute and preventive migraine treatment. Cannabinoids also demonstrate dopamine-blocking and anti-inflammatory effects. AEA is tonically active in the periaqueductal gray matter, a migraine generator. THC modulates glutamatergic neurotransmission via NMDA receptors. Fibromyalgia is now conceived as a central sensitization state with secondary hyperalgesia. Cannabinoids have similarly demonstrated the ability to block spinal, peripheral and gastrointestinal mechanisms that promote pain in headache, fibromyalgia, IBS and related disorders. The past and potential clinical utility of cannabis-based medicines in their treatment is discussed, as are further suggestions for experimental investigation of CECD via CSF examination and neuro-imaging.

CONCLUSION:

Migraine, fibromyalgia, IBS and related conditions display common clinical, biochemical and pathophysiological patterns that suggest an underlying clinical endocannabinoid deficiency that may be suitably treated with cannabinoid medicines.”

http://www.ncbi.nlm.nih.gov/pubmed/18404144

The endocannabinoid system and migraine.

Abstract

“The recently discovered endocannabinoid system (ECS), which includes endocannabinoids and the proteins that metabolize and bind them, has been implicated in multiple regulatory functions both in health and disease. Several studies have suggested that ECS is centrally and peripherally involved in the processing of pain signals. This finding is corroborated by the evidence that endocannabinoids inhibit, through a cannabinoid type-1 receptor (CB1R)-dependent retrograde mechanism, the release of neurotransmitters controlling nociceptive inputs and that the levels of these lipids are high in those regions (such as sensory terminals, skin, dorsal root ganglia) known to be involved in transmission and modulation of pain signals. In this review we shall describe experimental and clinical data that, intriguingly, demonstrate the link between endocannabinoids and migraine, a neurovascular disorder characterized by recurrent episodic headaches and caused by abnormal processing of sensory information due to peripheral and/or central sensitization. Although the exact ECS-dependent mechanisms underlying migraine are not fully understood, the available results strongly suggest that activation of ECS could represent a promising therapeutical tool for reducing both the physiological and inflammatory components of pain that are likely involved in migraine attacks.”

http://www.ncbi.nlm.nih.gov/pubmed/20353780

Endocannabinoids in Chronic Migraine: CSF Findings Suggest a System Failure

Abstract

“Based on experimental evidence of the antinociceptive action of endocannabinoids and their role in the modulation of trigeminovascular system activation, we hypothesized that the endocannabinoid system may be dysfunctional in chronic migraine (CM). We examined whether the concentrations of N-arachidonoylethanolamide (anandamide, AEA), palmitoylethanolamide (PEA), and 2-arachidonoylglycerol (2-AG) in the CSF of patients with CM and with probable CM and probable analgesic-overuse headache (PCM+PAOH) are altered compared with control subjects. The above endocannabinoids were measured by high-performance liquid chromatography (HPLC), and quantified by isotope dilution gas-chromatography/mass-spectrometry. Calcitonin gene-related peptide (CGRP) levels were also determined by RIA method and the end products of nitric oxide (NO), the nitrites, by HPLC. CSF concentrations of AEA were significantly lower and those of PEA slightly but significantly higher both in patients with CM and PCM+PAOH than in nonmigraineur controls (p<0.01 and p<0.02, respectively). A negative correlation was found between AEA and CGRP levels in CM and PCM+PAOH patients (r=0.59, p<0.01 and r=-0.65, p<0.007; respectively). A similar trend was observed between this endocannabinoid and nitrite levels. Reduced levels of AEA in the CSF of CM and PCM+PAOH patients may reflect an impairment of the endocannabinoid system in these patients, which may contribute to chronic head pain and seem to be related to increased CGRP and NO production. These findings support the potential role of the cannabinoid (CB)1 receptor as a possible therapeutic target in CM.

A clinical endocannabinoid deficiency (CECD) has been hypothesized to underlie the pathophysiology of migraine, fibromyalgia, irritable bowel syndrome (IBS), and other functional conditions alleviated by clinical cannabis but no clear evidence to support this deficiency has been reported until now in this regard (Russo, 2004).”

http://www.nature.com/npp/journal/v32/n6/full/1301246a.html

Interictal type 1 cannabinoid receptor binding is increased in female migraine patients.

“BACKGROUND:

It has been suggested that endocannabinoid deficiency may play a role in the pathophysiology of migraine. Nonetheless, biochemical studies substantiating this idea remain scarce and are faced with methodological shortcomings partly because of the difficulty to perform measurements of endocannabinoids within the central nervous system itself.

CONCLUSION:

The increased interictal CB1R binding, especially in brain regions that exert top-down influences to modulate pain, supports the idea that endocannibinoid deficiency is present in female patients suffering from episodic migraine.”

http://www.ncbi.nlm.nih.gov/pubmed/22077199

 

Cannabinoids, Endocannabinoids and Cancer

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“The endocannabinoid system consists of an array of endogenously produced bioactive lipids that activate cannabinoid receptors. Although the primary focus of endocannabinoid biology has been on neurological and psychiatric effects, recent work has revealed several important interactions between the endocannabinoid system and cancer. Several different types of cancer have abnormal regulation of the endocannabinoid system that contributes to cancer progression and correlates to clinical outcomes.

Modulation of the endocannabinoid system by pharmacological agents in various cancer types reveals that it can mediate antiproliferative and apoptotic effects by both cannabinoid receptor-dependent and -independent pathways. Selective agonists and antagonists of the cannabinoid receptors, inhibitors of endocannabinoid hydrolysis, and cannabinoid analogs have been utilized to probe the pathways involved in the effects of the endocannabinoid system on cancer cell apoptosis, proliferation, migration, adhesion, and invasion. The antiproliferative and apoptotic effects produced by some of these pharmacological probes reveal that the endocannabinoid system is a promising new target for the development of novel chemotherapeutics to treat cancer.”

Although there is a strong set of data in vitro, in cellular model systems, and in mouse model systems, there is a dearth of clinical data on the effects of cannabinoids in the treatment of cancer in humans. This fact is quite surprising considering the large library of compounds that have been developed and used to study the effects of cannabinoids on cancer in model systems.

Despite the lack of preclinical and clinical data, there is a strong agreement that pharmacological targeting of the endocannabinoid system is emerging as one of the most promising new methods for reducing the progression of cancer. In particular, combination therapy utilizing both traditional chemotherapeutics and molecules targeting the endocannabinoid system may be an excellent next generation treatment for cancer.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3366283/

The endocannabinoid system in cancer-potential therapeutic target?

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“Endogenous arachidonic acid metabolites with properties similar to compounds of Cannabis sativa Linnaeus, the so-called endocannabinoids, have effects on various types of cancer. Although endocannabinoids and synthetic cannabinoids may have pro-proliferative effects, predominantly inhibitory effects on tumor growth, angiogenesis, migration and metastasis have been described. Remarkably, these effects may be selective for the cancer cells, while normal cells and tissues are spared. Such apparent tumor cell selectivity makes the endocannabinoid system an attractive potential target for cancer therapy. In this review we discuss various means by which the endocannabinoid system may be targeted in cancer and the current knowledge considering the regulation of the endocannabinoid system in malignancy.”  http://www.ncbi.nlm.nih.gov/pubmed/18249558

http://www.sciencedirect.com/science/article/pii/S1044579X07001058

Cannabimimetic fatty acid derivatives in cancer and inflammation.

“Evidence for the role of the cannabimimetic fatty acid derivatives (CFADs), i.e. anandamide (arachidonoylethanolamide, AEA), 2-arachidonoylglycerol (2-AG) and palmitoylethanolamide (PEA), in the control of inflammation and of the proliferation of tumor cells is reviewed here. The biosynthesis of AEA, PEA, or 2-AG can be induced by stimulation with either Ca(2+) ionophores, lipopolysaccharide, or platelet activating factor in macrophages, and by ionomycin or antigen challenge in rat basophilic leukemia (RBL-2H3) cells (a widely used model for mast cells). These cells also inactivate CFADs through re-uptake and/or hydrolysis and/or esterification processes. AEA and PEA modulate cytokine and/or arachidonate release from macrophages in vitro, regulate serotonin secretion from RBL-2H3 cells, and are analgesic in some animal models of inflammatory pain. However, the involvement of endogenous CFADs and cannabinoid CB(1) and CB(2) receptors in these effects is still controversial. In human breast and prostate cancer cells, AEA and 2-AG, but not PEA, potently inhibit prolactin and/or nerve growth factor (NGF)-induced cell proliferation. Vanillyl-derivatives of anandamide, such as olvanil and arvanil, exhibit even higher anti-proliferative activity. These effects are due to suppression of the levels of the 100 kDa prolactin receptor or of the high affinity NGF receptors (trk), are mediated by CB(1)-like cannabinoid receptors, and are enhanced by other CFADs. Inhibition of adenylyl cyclase and activation of mitogen-activated protein kinase underlie the anti-mitogenic actions of AEA. The possibility that CFADs act as local inhibitors of the proliferation of human breast cancer is discussed here.”

http://www.ncbi.nlm.nih.gov/pubmed/10785541

The endogenous cannabinoid anandamide inhibits human breast cancer cell proliferation

“Anandamide was the first brain metabolite shown to act as a ligand of “central” CB1 cannabinoid receptors. Here we report that the endogenous cannabinoid potently and selectively inhibits the proliferation of human breast cancer cells in vitro. Anandamide dose-dependently inhibited the proliferation of MCF-7 and EFM-19 cells with IC50 values between 0.5 and 1.5 microM and 83-92% maximal inhibition at 5-10 microM. The proliferation of several other nonmammary tumoral cell lines was not affected by 10 microM anandamide. The anti-proliferative effect of anandamide was not due to toxicity or to apoptosis of cells but was accompanied by a reduction of cells in the S phase of the cell cycle. A stable analogue of anandamide (R)-methanandamide, another endogenous cannabinoid, 2-arachidonoylglycerol, and the synthetic cannabinoid HU-210 also inhibited EFM-19 cell proliferation, whereas arachidonic acid was much less effective. These cannabimimetic substances displaced the binding of the selective cannabinoid agonist [3H]CP 55, 940 to EFM-19 membranes with an order of potency identical to that observed for the inhibition of EFM-19 cell proliferation. Moreover, anandamide cytostatic effect was inhibited by the selective CB1 receptor antagonist SR 141716A. Cell proliferation was arrested by a prolactin mAb and enhanced by exogenous human prolactin, whose mitogenic action was reverted by very low (0.1-0.5 microM) doses of anandamide. Anandamide suppressed the levels of the long form of the prolactin receptor in both EFM-19 and MCF-7 cells, as well as a typical prolactin-induced response, i.e., the expression of the breast cancer cell susceptibility gene brca1. These data suggest that anandamide blocks human breast cancer cell proliferation through CB1-like receptor-mediated inhibition of endogenous prolactin action at the level of prolactin receptor.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC20983/

Omega-3 N-acylethanolamines are endogenously synthesised from omega-3 fatty acids in different human prostate and breast cancer cell lines.

“Omega-3 (n-3) fatty acids inhibit breast and prostate cancer cell growth. We previously showed that N-acylethanolamine derivatives of n-3 (n-3-NAE) are endocannabinoids, which regulate cancer cell proliferation. These n-3-NAE are synthesised in certain cells/tissues, after supplementing with fatty acids, however, no one has assessed whether and to what extent this occurs in cancer cells. We determined levels of endogenous n-3-NAEs in hormone sensitive and insensitive prostate and breast cancer cells and subsequent effects on other endocannabinoids (anandamide and 2-arachidonoylglycerol), before and after supplementing with DHA and EPA fatty acids, using HPLC tandem mass spectrometry. This is the first study reporting that n-3-NAEs are synthesised from their parent n-3 fatty acids in cancer cells, regardless of tumour type, hormone status or the presence of fatty acid amide hydrolase. This could have important implications for the use of n-3 fatty acids as therapeutic agents in breast and prostate cancers expressing cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/21995886

Anandamide inhibits Cdk2 and activates Chk1 leading to cell cycle arrest in human breast cancer cells.

“This study was designed to determine the molecular mechanisms underlying the anti-proliferative effect of the endocannabinoid anandamide on highly invasive human breast cancer cells, MDA-MB-231. We show that a metabolically stable analogue of anandamide, Met-F-AEA, induces an S phase growth arrest correlated with Chk1 activation, Cdc25A degradation and suppression of Cdk2 activity. These findings demonstrate that Met-F-AEA induced cell cycle blockade relies on modulated expression and activity of key S phase regulatory proteins. The observed mechanism of action, already reported for well-known chemotherapeutic drugs, provides strong evidence for a direct role of anandamide related compounds in the activation of cell cycle checkpoints.”

http://www.ncbi.nlm.nih.gov/pubmed/17055492