Author Archives: David Worrell

Alteration of the endocannabinoid system in mouse brain during prion disease.

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“Prion diseases are neurodegenerative disorders characterized by deposition of the pathological prion protein (PrPsc) within the brain of affected humans and animals. Microglial cell activation is a common feature of prion diseases; alterations of various neurotransmitter systems and neurotransmission have been also reported. Owing to its ability to modulate both neuroimmune responses and neurotransmission, it was of interest to study the brain endocannabinoid system in a prion-infected mouse model. The production of the endocannabinoid, 2-arachidonoyglycerol (2-AG), was enhanced 10 weeks post-infection, without alteration of the other endocannabinoid, anandamide. The CB2 receptor expression was up-regulated in brains of prion-infected mice as early as 10 weeks and up to 32 weeks post-infection whereas the mRNAs of other cannabinoid receptors (CBRs) remain unchanged. The observed alterations of the endocannabinoid system were specific for prion infection since no significant changes were observed in the brain of prion-resistant mice, that is, mice devoid of the Prnp gene. Our study highlights important alterations of the endocannabinoid system during early stages of the disease long before the clinical signs of the disease.”  https://www.ncbi.nlm.nih.gov/pubmed/21195746

“Prion diseases are a group of neurodegenerative diseases caused by prions, which are “proteinaceous infectious particles.” Prion diseases are caused by misfolded forms of the prion protein, also known as PrP. These diseases affect a lot of different mammals in addition to humans. The human forms of prion disease are most often the names Creutzfeldt-Jakob disease (CJD), fatal familial insomnia (FFI), Gertsmann-Straussler-Scheinker syndrome (GSS), kuru and variably protease-sensitive prionopathy (VPSPr). All of these diseases are caused by just slightly different versions of the same protein, so we refer to them all as prion diseases.” http://www.prionalliance.org/2013/12/02/what-are-human-prion-diseases/
 
“Eating meat contaminated with bovine spongiform encephalopathy and its hallmark misshapen proteins, called prions, can cause a fatal and untreatable brain disorder,” http://www.sciencemag.org/news/2016/12/mad-cow-disease-remains-threat-new-blood-tests-could-detect-it
 
“Prions are terrifying.”
“Marijuana Kills MRSA and Inhibits Prions That Cause Neurodegenerative Disease; Still Recognized by Feds As a Dangerous Drug.” http://www.medicaldaily.com/marijuana-kills-mrsa-and-inhibits-prions-cause-neurodegenerative-disease-still-recognized-feds
 
 
“Antibacterial cannabinoids from Cannabis sativa: a structure-activity study.” http://www.ncbi.nlm.nih.gov/pubmed/18681481
 
“Nonpsychoactive Cannabidiol Prevents Prion Accumulation and Protects Neurons against Prion Toxicity. Our results suggest that CBD may protect neurons against the multiple molecular and cellular factors involved in the different steps of the neurodegenerative process, which takes place during prion infection. When combined with its ability to target the brain and its lack of toxic side effects, CBD may represent a promising new anti-prion drug. ” http://www.jneurosci.org/content/27/36/9537.full
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Historical perspective on the medical use of cannabis for epilepsy: Ancient times to the 1980s.

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“There has been a dramatic surge in the interest of utilizing cannabis for epilepsy treatment in the US. Yet, access to cannabis for research and therapy is mired in conflicting regulatory policies and shifting public opinion. Understanding the current state of affairs in the medical cannabis debate requires an examination of the history of medical cannabis use. From ancient Chinese pharmacopeias to the current Phase III trials of pharmaceutical grade cannabidiol, this review covers the time span of cannabis use for epilepsy therapy so as to better assess the issues surrounding the modern medical opinion of cannabis use. This article is part of a Special Issue titled Cannabinoids and Epilepsy.” https://www.ncbi.nlm.nih.gov/pubmed/28089286 http://www.thctotalhealthcare.com/category/epilepsy-2/]]>

Oral cannabidiol does not produce a signal for abuse liability in frequent marijuana smokers.

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“Cannabidiol (CBD) is a naturally occurring constituent of the marijuana plant. In the past few years, there has been great interest in the therapeutic effects of isolated CBD and it is currently being explored for numerous disease conditions (e.g., pain, epilepsy, cancer, various drug dependencies). However, CBD remains a Schedule I drug on the U.S. Controlled Substances Act (CSA). Despite its status, there are no well-controlled data available regarding its abuse liability.

Overall, CBD did not display any signals of abuse liability at the doses tested and these data may help inform U.S. regulatory decisions regarding CBD schedule on the CSA.” https://www.ncbi.nlm.nih.gov/pubmed/28088032]]>

Pharmacology of cannabinoids in the treatment of epilepsy.

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“The use of cannabis products in the treatment of epilepsy has long been of interest to researchers and clinicians alike; however, until recently very little published data were available to support its use. This article summarizes the available scientific data of pharmacology from human and animal studies on the major cannabinoids which have been of interest in the treatment of epilepsy, including ∆9-tetrahydrocannabinol (∆9-THC), cannabidiol (CBD), ∆9-tetrahydrocannabivarin (∆9-THCV), cannabidivarin (CBDV), and ∆9-tetrahydrocannabinolic acid (Δ9-THCA). It has long been known that ∆9-THC has partial agonist activity at the endocannabinoid receptors CB1 and CB2, though it also binds to other targets which may modulate neuronal excitability and neuroinflammation. The actions of Δ9-THCV and Δ9-THCA are less well understood. In contrast to ∆9-THC, CBD has low affinity for CB1 and CB2 receptors and other targets have been investigated to explain its anticonvulsant properties including TRPV1, voltage gated potassium and sodium channels, and GPR55, among others. We describe the absorption, distribution, metabolism, and excretion of each of the above mentioned compounds. Cannabinoids as a whole are very lipophilic, resulting in decreased bioavailability, which presents challenges in optimal drug delivery. Finally, we discuss the limited drug-drug interaction data available on THC and CBD. As cannabinoids and cannabis-based products are studied for efficacy as anticonvulsants, more investigation is needed regarding the specific targets of action, optimal drug delivery, and potential drug-drug interactions.” https://www.ncbi.nlm.nih.gov/pubmed/28087250]]>

Developmental Role of Macrophage Cannabinoid-1 Receptor Signaling in Type-2 Diabetes.

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“Islet inflammation promotes β-cell loss and type-2 diabetes (T2D), a process replicated in Zucker Diabetic Fatty (ZDF) rats in which β-cell loss has been linked to cannabinoid-1 receptor (CB1R)-induced pro-inflammatory signaling in macrophages infiltrating pancreatic islets. Here, we analyzed CB1R signaling in macrophages and its developmental role in T2Dα. ZDF rats with global deletion of CB1R are protected from β-cell loss, hyperglycemia and nephropathy present in ZDF littermates. Adoptive transfer of CB1R-/- bone marrow to ZDF rats also prevents β-cell loss and hyperglycemia, but not nephropathy. ZDF islets contain elevated levels of CB1R, IL-1β, TNF-α, the chemokine CCL2 and interferon regulatory factor-5 (IRF5), a marker of M1 inflammatory macrophage polarization. In primary cultured rodent and human macrophages, CB1R activation increased Irf5 expression, whereas knockdown of Irf5 blunted CB1R-induced secretion of inflammatory cytokines without affecting CCL2 expression, which was p38MAPKα-dependent. Macrophage-specific in vivo knockdown of Irf5 protected ZDF rats from β-cell loss and hyperglycemia. Thus, IRF5 is a crucial downstream mediator of diabetogenic CB1R signaling in macrophages and a potential therapeutic target.” https://www.ncbi.nlm.nih.gov/pubmed/28082458]]>

Influence of history of cannabis smoking in selected donors on the outcomes of lung transplantation.

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“Cannabis is the most commonly abused illicit drug and the smokers are at the risk of lung infections, bullous emphysema and lung cancer. However, no evidence about the outcomes of lung transplantation (LTx) utilizing the lungs from such donors is available in the literature. The history of donor cannabis smoking does not appear to affect early and mid-term outcomes after LTx and potentially improve the donor pool. As it does not seem to negatively affect the outcomes after LTx, it should not be per se considered a contraindication for lung donation.” https://www.ncbi.nlm.nih.gov/pubmed/28077504 “Transplantation is one critical area of medicine that requires the use of immunosuppressants. Cannabinoids have emerged as powerful drug candidates for the treatment of inflammatory and autoimmune diseases due to their immunosuppressive properties. Cannabinoids are the tetrophenolic compounds found in the plant, Cannabis sativa.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2923447/]]>

Manipulation of the Endocannabinoid System in Colitis: A Comprehensive Review.

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Image result for inflammatory bowel diseases journal “Inflammatory bowel disease (IBD) is a lifelong disease of the gastrointestinal tract whose annual incidence and prevalence is on the rise. Current immunosuppressive therapies available for treatment of IBD offer limited benefits and lose effectiveness, exposing a significant need for the development of novel therapies. In the clinical setting, cannabis has been shown to provide patients with IBD symptomatic relief, although the underlying mechanisms of their anti-inflammatory effects remain unclear.

RESULTS:

Cannabinoid receptors 1 and 2, endogenous cannabinoids, and atypical cannabinoids are upregulated in inflammation, and their presence and stimulation attenuate murine colitis, whereas cannabinoid receptor antagonism and cannabinoid receptor deficient models reverse these anti-inflammatory effects. In addition, inhibition of endocannabinoid degradation through monoacylglycerol lipase and fatty acid amide hydrolase blockade can also attenuate colitis development, and is closely linked to cannabinoid receptor expression.

CONCLUSIONS:

Although manipulation of the endocannabinoid system in murine colitis has proven to be largely beneficial in attenuating inflammation, there is a paucity of human study data. Further research is essential to clearly elucidate the specific mechanisms driving this anti-inflammatory effect for the development of therapeutics to target inflammatory disease such as IBD.” https://www.ncbi.nlm.nih.gov/pubmed/28079617 “Plant cannabinoids THC and CBD proved beneficial in DNBS-induced colitis in a bell-shaped dose-related response, but more importantly, the effects of the phytocannabinoids were additive, as CBD increased an ineffective THC dose to the level of an effective one.” https://academic.oup.com/ibdjournal/article/23/2/192/4347176
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