“In animal studies, four times less morphine and ten times less codeine was needed when cannabinoids were given at the same time.
Monthly Archives: June 2017
The cannabinoid system and pain.
“Chronic pain states are highly prevalent and yet poorly controlled by currently available analgesics, representing an enormous clinical, societal, and economic burden. Existing pain medications have significant limitations and adverse effects including tolerance, dependence, gastrointestinal dysfunction, cognitive impairment, and a narrow therapeutic window, making the search for novel analgesics ever more important. In this article, we review the role of an important endogenous pain control system, the endocannabinoid (EC) system, in the sensory, emotional, and cognitive aspects of pain. Herein, we briefly cover the discovery of the EC system and its role in pain processing pathways, before concentrating on three areas of current major interest in EC pain research; 1. Pharmacological enhancement of endocannabinoid activity (via blockade of EC metabolism or allosteric modulation of CB1receptors); 2. The EC System and stress-induced modulation of pain; and 3. The EC system & medial prefrontal cortex (mPFC) dysfunction in pain states. Whilst we focus predominantly on the preclinical data, we also include extensive discussion of recent clinical failures of endocannabinoid-related therapies, the future potential of these approaches, and important directions for future research on the EC system and pain.”
https://www.ncbi.nlm.nih.gov/pubmed/28625720
http://www.sciencedirect.com/science/article/pii/S002839081730285X
Synaptic functions of endocannabinoid signaling in health and disease.
“Endocannabinoids (eCBs) are a family of lipid molecules that act as key regulators of synaptic transmission and plasticity. They are synthetized “on demand” following physiological and/or pathological stimuli. Once released from postsynaptic neurons, eCBs typically act as retrograde messengers to activate presynaptic type 1 cannabinoid receptors (CB1) and induce short- or long-term depression of neurotransmitter release. Besides this canonical mechanism of action, recent findings have revealed a number of less conventional mechanisms by which eCBs regulate neural activity and synaptic function, suggesting that eCB-mediated plasticity is mechanistically more diverse than anticipated. These mechanisms include non-retrograde signaling, signaling via astrocytes, participation in long-term potentiation, and the involvement of mitochondrial CB1. Focusing on paradigmatic brain areas, such as hippocampus, striatum, and neocortex, we review typical and novel signaling mechanisms, and discuss the functional implications in normal brain function and brain diseases. In summary, eCB signaling may lead to different forms of synaptic plasticity through activation of a plethora of mechanisms, which provide further complexity to the functional consequences of eCB signaling.”
https://www.ncbi.nlm.nih.gov/pubmed/28625718
http://www.sciencedirect.com/science/article/pii/S0028390817302861
Assessing the role of serotonergic receptors in cannabidiol’s anticonvulsant efficacy.
“Cannabidiol (CBD) is a phytocannabinoid that has demonstrated anticonvulsant efficacy in several animal models of seizure. The current experiment validated CBD’s anticonvulsant effect using the acute pentylenetetrazol (PTZ) model.
While this work further confirms the anticonvulsant efficacy of CBD and supports its application in the treatment of human seizure disorders, additional research on CBD’s mechanism of action must be conducted.”
https://www.ncbi.nlm.nih.gov/pubmed/28624721
http://www.epilepsybehavior.com/article/S1525-5050(17)30122-1/fulltext
Metabolism of the Endocannabinoid Anandamide: Open Questions after 25 Years.
“Cannabis extracts have been used for centuries, but its main active principle ∆9-tetrahydrocannabinol (THC) was identified about 50 years ago. Yet, it is only 25 years ago that the first endogenous ligand of the same receptors engaged by the cannabis agents was discovered. This “endocannabinoid (eCB)” was identified as N-arachidonoylethanolamine (or anandamide (AEA)), and was shown to have several receptors, metabolic enzymes and transporters that altogether drive its biological activity. Here I report on the latest advances about AEA metabolism, with the aim of focusing open questions still awaiting an answer for a deeper understanding of AEA activity, and for translating AEA-based drugs into novel therapeutics for human diseases.”
http://journal.frontiersin.org/article/10.3389/fnmol.2017.00166/full
Endocannabinoid System in Neurodegenerative Disorders.
“Most neurodegenerative disorders (NDDs) are characterized by cognitive impairment and other neurological defects. The definite cause of and pathways underlying the progression of these NDDs are not well defined. Several mechanisms have been proposed to contribute to the development of NDDs. These mechanisms may proceed concurrently or successively, and they differ among cell types at different developmental stages in distinct brain regions. The endocannabinoid system, which involves cannabinoid receptors type 1 (CB1R) and type 2 (CB2R), endogenous cannabinoids and the enzymes that catabolize these compounds, has been shown to contribute to the development of NDDs in several animal models and human studies. In this review, we discuss the functions of the endocannabinoid (EC) system in NDDs and converse the therapeutic efficacy of targeting the endocannabinoid system to rescue NDDs.”
https://www.ncbi.nlm.nih.gov/pubmed/28608560
http://onlinelibrary.wiley.com/doi/10.1111/jnc.14098/abstract
Quality of Life in Childhood Epilepsy in pediatric patients enrolled in a prospective, open-label clinical study with cannabidiol.
“Recent clinical trials indicate that cannabidiol (CBD) may reduce seizure frequency in pediatric patients with certain forms of treatment-resistant epilepsy. Many of these patients experience significant impairments in quality of life (QOL) in physical, mental, and social dimensions of health. In this study, we measured the caregiver-reported Quality of Life in Childhood Epilepsy (QOLCE) in a subset of patients enrolled in a prospective, open-label clinical study of CBD. Results from caregivers of 48 patients indicated an 8.2 ± 9.9-point improvement in overall patient QOLCE (p < 0.001) following 12 weeks of CBD. Subscores with improvement included energy/fatigue, memory, control/helplessness, other cognitive functions, social interactions, behavior, and global QOL. These differences were not correlated to changes in seizure frequency or adverse events. The results suggest that CBD may have beneficial effects on patient QOL, distinct from its seizure-reducing effects; however, further studies in placebo-controlled, double-blind trials are necessary to confirm this finding.”
https://www.ncbi.nlm.nih.gov/pubmed/28617940
http://onlinelibrary.wiley.com/doi/10.1111/epi.13815/abstract
A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study.
“Cannabidiol (CBD) is a nonpsychoactive phytocannabinoid used in multiple sclerosis and intractable epilepsies. Preclinical studies show CBD has numerous cardiovascular benefits, including a reduced blood pressure (BP) response to stress. The aim of this study was to investigate if CBD reduces BP in humans.
CONCLUSIONS:
This data shows that acute administration of CBD reduces resting BP and the BP increase to stress in humans, associated with increased HR. These hemodynamic changes should be considered for people taking CBD. Further research is required to establish whether CBD has a role in the treatment of cardiovascular disorders.”
https://www.ncbi.nlm.nih.gov/pubmed/28614793
“Our data show that a single dose of CBD reduces resting blood pressure and the blood pressure response to stress. This may reflect the anxiolytic and analgesic effects of CBD, as well as any potential direct cardiovascular effects. CBD has multiple desirable effects on the cardiovascular system” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5470879/
Cannabidiol upregulates melanogenesis through CB1 dependent pathway by activating p38 MAPK and p42/44 MAPK.
“Melanogenesis plays a critical role in the protection of skin against external stresses such as ultraviolet irradiation and oxidative stressors. This study was aimed to investigate the effects of cannabidiol on melanogenesis and its mechanisms of action in human epidermal melanocytes. We found that cannabidiol increased both melanin content and tryrosinase activity. The mRNA levels of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein (TRP) 1, and TRP2 were increased following cannabidiol treatment. Likewise, cannabidiol increased the protein levels of MITF, TRP 1, TRP 2, and tyrosinase. Mechanistically, we found that cannabidiol regulated melanogenesis by upregulating MITF through phosphorylation of p38 mitogen-activated protein kinase (MAPK) and p42/44 MAPK, independent of cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling. In addition, the melanogenic effect of cannabidiol was found to be mediated by cannabinoid CB1 receptor, not by CB2receptor. Taken together, these findings indicate that cannabidiol-induced melanogenesis is cannabinoid CB1 receptor-dependent, and cannabidiol induces melanogenesis through increasing MITF gene expression which is mediated by activation of p38 MAPK and p42/44 MAPK. Our results suggest that cannabidiol might be useful as a protective agent against external stresses.”
https://www.ncbi.nlm.nih.gov/pubmed/28601556
http://www.sciencedirect.com/science/article/pii/S0009279716304343
Regulation of human glioblastoma cell death by combined treatment of cannabidiol, γ-radiation and small molecule inhibitors of cell signaling pathways.
“Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. The challenging problem in cancer treatment is to find a way to upregulate radiosensitivity of GBM while protecting neurons and neural stem/progenitor cells in the brain. The goal of the present study was upregulation of the cytotoxic effect of γ-irradiation in GBM by non-psychotropic and non-toxic cannabinoid, cannabidiol (CBD).
We emphasized three main aspects of signaling mechanisms induced by CBD treatment (alone or in combination with γ-irradiation) in human GBM that govern cell death: 1) CBD significantly upregulated the active (phosphorylated) JNK1/2 and MAPK p38 levels with the subsequent downregulation of the active phospho-ERK1/2 and phospho-AKT1 levels. MAPK p38 was one of the main drivers of CBD-induced cell death, while death levels after combined treatment of CBD and radiation were dependent on both MAPK p38 and JNK. Both MAPK p38 and JNK regulate the endogenous TRAIL expression. 2) NF-κB p65-P(Ser536) was not the main target of CBD treatment and this transcription factor was found at high levels in CBD-treated GBM cells. Additional suppression of p65-P(Ser536) levels using specific small molecule inhibitors significantly increased CBD-induced apoptosis. 3) CBD treatment substantially upregulated TNF/TNFR1 and TRAIL/TRAIL-R2 signaling by modulation of both ligand and receptor levels followed by apoptosis.
Our results demonstrate that radiation-induced death in GBM could be enhanced by CBD-mediated signaling in concert with its marginal effects for neural stem/progenitor cells and astrocytes. It will allow selecting efficient targets for sensitization of GBM and overcoming cancer therapy-induced severe adverse sequelae.”