Tag Archives: Cannabinoids

Medical Marijuana-Opportunities and Challenges

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“Over the recent years, public and political opinions have demonstrated increasing support for the legalization of medical marijuana.

To date, 24 states as well as the District of Columbia have legalized cannabis for medical use, 4 states have legalized the recreational use of Marijuana.

Marijuana is derived from the hemp plant Cannabis sativa. Δ-9-tetrahydrocannabinol (THC) is the major psychoactive constituent of cannabis, while cannabidiol (CBD) is the major non-psychoactive constituent. THC is a partial agonist at CB1 and CB2 receptors, while CBD at high levels is an antagonist CB1 and CB2.

CB1 is abundantly expressed in the brain, and CB2 is expressed on immune cells (expression of CB2 on neurons remains controversial). The brain also produces endogenous cannabis-like substances (endocannabinoids) that bind and activate the CB1/CB2 receptors.

There is tremendous interest in harnessing the therapeutic potential of plant-derived and synthetic cannabinoids.

This Editorial provides an overview of diseases that may be treated by cannabinoids.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4948749/

Effective treatment of spasticity using dronabinol in pediatric palliative care.

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“Cannabis extracts have a wide therapeutic potential but in many countries they have not been approved for treatment in children so far.

We conducted an open, uncontrolled, retrospective study on the administration of dronabinol to determine the value, efficacy, and safety of cannabis-based medicines in the treatment of refractory spasticity in pediatric palliative care.

Sixteen children, adolescents and young adults having complex neurological conditions with spasticity (aged 1.3-26.6 years, median 12.7 years) were treated with dronabinol by our specialized pediatric palliative care team between 01.12.2010 and 30.04.2015 in a home-care setting. Therapeutic efficacy and side effects were closely monitored.

RESULTS:

Drops of the 2.5% oily tetrahydrocannabinol solution (dronabinol) were administered. A promising therapeutic effect was seen, mostly due to abolishment or marked improvement of severe, treatment resistant spasticity (n = 12). In two cases the effect could not be determined, two patients did not benefit. The median duration of treatment was 181 days (range 23-1429 days). Dosages to obtain a therapeutic effect varied from 0.08 to 1.0 mg/kg/d with a median of 0.33 mg/kg/d in patients with a documented therapeutic effect. When administered as an escalating dosage scheme, side effects were rare and only consisted in vomiting and restlessness (one patient each).

No serious and enduring side effects occurred even in young children and/or over a longer period of time.

CONCLUSIONS:

In the majority of pediatric palliative patients the treatment with dronabinol showed promising effects in treatment resistant spasticity.”

http://www.ncbi.nlm.nih.gov/pubmed/27506815

Cannabinoids As Potential Treatment for Chemotherapy-Induced Nausea and Vomiting.

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“Despite the advent of classic anti-emetics, chemotherapy-induced nausea is still problematic, with vomiting being somewhat better managed in the clinic.

If post-treatment nausea and vomiting are not properly controlled, anticipatory nausea-a conditioned response to the contextual cues associated with illness-inducing chemotherapy-can develop. Once it develops, anticipatory nausea is refractive to current anti-emetics, highlighting the need for alternative treatment options.

One of the first documented medicinal uses of Δ(9)-tetrahydrocannabinol (Δ(9)-THC) was for the treatment of chemotherapy-induced nausea and vomiting (CINV), and recent evidence is accumulating to suggest a role for the endocannabinoid system in modulating CINV.

Here, we review studies assessing the therapeutic potential of cannabinoids and manipulations of the endocannabinoid system in human patients and pre-clinical animal models of nausea and vomiting.”

http://www.ncbi.nlm.nih.gov/pubmed/27507945

The Effect of Muscarinic Receptor Modulators on the Antinociception Induced by CB2 Receptor Agonist, JWH133 in Mice.

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“There is no published study regarding the interaction between muscarinic receptor modulators and antinociception induced by cannabinoidreceptor (CB2) agonist. The effect of pilocarpine (a muscarinic agonist) and atropine (a muscarinic antagonist) on JWH-133 (a CB2 agonist) induced analgesia in mice was studied. First the analgesic effect of JWH-133 (0.001-1 mg/Kg) or pilocarpine (2.5-20 mg/kg) or atropine (0.2-5 mg/kg) was evaluated. Subsequently, the effect of co-administration of pilocarpine (2.5 mg/kg) or atropine (5 mg/kg) and JWH-133 (0.001-1 mg/Kg) were studied too. JWH-133 and pilocarpine provoked antinociception in mice but atropine did not. Pilocarpine potentiated the analgesic effect of JWH-133 but atropine antagonized that. It can be concluded that JWH-133 induced antinociception is affected by muscarinic receptor modulators in mice.”

http://www.ncbi.nlm.nih.gov/pubmed/27504865

The impact of drugs for multiple sclerosis on sleep.

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“Although there is a growing literature on the presence of sleep disorders in multiple sclerosis (MS), few studies have specifically addressed the impact of drugs on sleep of these patients. Moreover, even when sleep is considered, quantitative assessment by standardized questionnaires or polysomnography is lacking.

The studies that have been done highlight that interferon-beta and some symptomatic medications may affect sleep, thus contributing to fatigue, depression, and poor quality of life; conversely, natalizumab and cannabinoids may improve sleep.

Common limitations of the literature reviewed here are small sample size, selection bias, and often a lack of objective outcome measures. Clinicians need to remember to ask about sleep in all MS patients and intervene when appropriate. A systematic approach that takes sleep into account is recommended to enhance recognition and appropriate management of sleep disruption, including disorders related to medication. Consideration of the impact on sleep should also be part of the design of trials of new therapies.”

http://www.ncbi.nlm.nih.gov/pubmed/27503906

Endocannabinoid signaling enhances visual responses through modulation of intracellular chloride levels in retinal ganglion cells.

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“Type 1 cannabinoid receptors (CB1Rs) are widely expressed in the vertebrate retina but the role of endocannabinoids in vision is not fully understood. Here we identified a novel mechanism underlying a CB1R-mediated increase in retinal ganglion cell (RGC) intrinsic excitability acting through AMPK-dependent inhibition of NKCC1 activity.

Clomeleon imaging and patch clamp recordings revealed that inhibition of NKCC1 downstream of CB1R activation reduces intracellular Cl– levels in RGCs, hyperpolarizing the resting membrane potential. We confirmed that such hyperpolarization enhances RGC action potential firing in response to subsequent depolarization, consistent with the increased intrinsic excitability of RGCs observed with CB1R activation.

Using a dot avoidance assay in freely swimming Xenopus tadpoles we demonstrate that CB1R activation markedly improves visual contrast sensitivity under low light conditions.

These results highlight a role for endocannabinoids in vision, and present a novel mechanism for cannabinoid modulation of neuronal activity through Cl– regulation.”

http://www.ncbi.nlm.nih.gov/pubmed/27501334

Mice Expressing a “Hyper-Sensitive” Form of the Cannabinoid Receptor 1 (CB1) Are Neither Obese Nor Diabetic.

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“Multiple lines of evidence implicate the endocannabinoid signaling system in the modulation of metabolic disease.

Genetic or pharmacological inactivation of CB1 in rodents leads to reduced body weight, resistance to diet-induced obesity, decreased intake of highly palatable food, and increased energy expenditure.

Cannabinoid agonists stimulate feeding in rodents and increased levels of endocannabinoids can disrupt lipid metabolism. Therefore, the hypothesis that sustained endocannabinoid signaling can lead to obesity and diabetes was examined in this study using S426A/S430A mutant mice expressing a desensitization-resistant CB1 receptor.

These mice display exaggerated and prolonged responses to acute administration of phytocannabinoids, synthetic cannabinoids, and endocannabinoids. As a consequence these mice represent a novel model for determining the effect of enhanced endocannabinoid signaling on metabolic disease.

Our results indicate that S426A/S430A mutant mice expressing the desensitization-resistant form of CB1 do not exhibit differences in body weight, food intake, glucose homeostasis, or re-feeding following a fast.”

http://www.ncbi.nlm.nih.gov/pubmed/27501235

Inhibition of interleukin-8 release in the human colonic epithelial cell line HT-29 by cannabinoids.

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“We have investigated the effects of cannabinoid agonists and antagonists on tumour necrosis factor-alpha (TNF-alpha)-induced secretion of interleukin-8 from the colonic epithelial cell line, HT-29.

The cannabinoid receptor agonists [(-)-3-[2-hydroxy-4-(1,1-dimethyl-heptyl)-phenyl]4-[3-hydroxypropyl]cyclo-hexan-1-ol] (CP55,940); Delta-9-tetrahydrocannabinol; [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl) methyl] pyrrolo[1,2,3-de]1,4-benzoxazin-6-yl](1-naphthyl) methanone mesylate] (WIN55,212-2) and 1-propyl-2-methyl-3-naphthoyl-indole (JWH 015) inhibited TNF-alpha induced release of interleukin-8 in a concentration-dependent manner.

We conclude that in HT-29 cells, TNF-alpha-induced interleukin-8 release is inhibited by cannabinoids through activation of cannabinoid CB(2) receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/12498928

“Essential involvement of interleukin-8 (IL-8) in acute inflammation.”  http://www.ncbi.nlm.nih.gov/pubmed/7964163

“Interleukin-8 (IL-8) is known to possess tumorigenic and proangiogenic properties. Overexpression of IL-8 has been detected in many human tumors, including colorectal cancer (CRC). IL-8 promotes tumor growth, metastasis, chemoresistance and angiogenesis, implying IL-8 to be an important therapeutic target in CRC.”  http://www.ncbi.nlm.nih.gov/pubmed/20648559

Cannabinoid signalling in TNF-alpha induced IL-8 release.

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“The molecular events mediating the immunomodulatory properties of cannabinoids have remained largely unresolved.

We have therefore investigated the molecular mechanism(s) through which R-(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl] pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-napthanlenyl) methanone (WIN55212-2) modulate production of interleukin-8 (IL-8) in HT-29 cells.

Release of IL-8 induced by tumor necrosis factor-alpha (TNF-alpha) was determined by enzyme-linked immunosorbent assay (ELISA). Changes in expression of inhibitory kappa B (IkappaB) were monitored by Western blotting and activation of nuclear factor-kappa B (NF-kappaB) was determined in electrophoretic mobility shift assay (EMSAs).

TNF-alpha induced release of IL-8 was inhibited by WIN55212-2 which also blocked the degradation of IkappaB-alpha and activation of NF-kappaB induced by TNF-alpha.

These data provide strong evidence that WIN55212-2 may modulate IL-8 release by negatively regulating the signaling cascade leading to the activation of NF-kappaB.

These findings highlight a potential mechanism for the immunomodulatory properties of cannabinoids and contribute towards acquiring a clear understanding of the role of cannabinoids in inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/16714014

“Essential involvement of interleukin-8 (IL-8) in acute inflammation.”  http://www.ncbi.nlm.nih.gov/pubmed/7964163

“Cannabinoids as novel anti-inflammatory drugs”  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2828614/