Cannabinoid-mediated modulation of neuropathic pain and microglial accumulation in a model of murine type I diabetic peripheral neuropathic pain.

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“Despite the frequency of diabetes mellitus and its relationship to diabetic peripheral neuropathy (DPN) and neuropathic pain (NeP), our understanding of underlying mechanisms leading to chronic pain in diabetes remains poor.

Recent evidence has demonstated a prominent role of microglial cells in neuropathic pain states.

One potential therapeutic option gaining clinical acceptance is the cannabinoids, for which cannabinoidreceptors (CB) are expressed on neurons and microglia. We studied the accumulation and activation of spinal and thalamic microglia in streptozotocin (STZ)-diabetic CD1 mice and the impact of cannabinoid receptor agonism/antagonism during the development of a chronic NeP state.

The prevention of microglial accumulation and activation in the dorsal spinal cord was associated with limited development of a neuropathic pain state.

Cannabinoids demonstrated antinociceptive effects in this mouse model of DPN.

These results suggest that such interventions may also benefit humans with DPN, and their early introduction may also modify the development of the NeP state.”  http://www.ncbi.nlm.nih.gov/pubmed/20236533

“Tetrahydrocannabinol (THC), a component in marijuana, acts at both CB1 and CB2 receptors, but other forms of cannabinoids such as cannabinol and cannabidiol act predominantly at CB2 receptors. Such CB2 agonists may be potential anti-inflammatory therapies, antagonizing the 2-AG-induced recruitment of microglia and impacting upon development of an inflammatory state. Such properties may permit the cannabinoids to act in the prevention of microglial activation, perhaps limiting the development of neuropathic pain.

The present data confirm the efficacy of cannabinoid agonists, both for the CB1 and CB2 receptor, in modulation of acute thermal and tactile hypersensitivity as features of neuropathic pain. Furthermore, CB1 agonism from the onset of the offending stimulus (diabetes) normally leading to neuropathic pain ameliorated the development of a neuropathic pain state.”  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2845559/

http://www.thctotalhealthcare.com/category/neuropathic-pain/

 

The role of cannabinoids in adult neurogenesis.

“Cannabinoids are a unique class of chemical compounds incorporating plant-derived cannabinoids (the active components of Cannabis sativa), the endogenous cannabinoids and synthetic cannabinoid ligands, and these compounds are becoming increasingly recognized for their roles in neural developmental processes.

Indeed, cannabinoids have clear modulatory roles in adult neurogenesis, likely through activation of both CB1 and CB2receptors.

In recent years a large body of literature has deciphered the signalling networks involved in cannabinoid-mediated regulation of neurogenesis. This timely review summarises the evidence that the cannabinoid system is intricately associated with neuronal differentiation and maturation of NPCs, and highlights intrinsic/extrinsic signalling mechanisms that are cannabinoid targets.

Overall these findings identify the central role of the cannabinoid system in adult neurogenesis in the hippocampus and the lateral ventricles, and hence provide insight into the processes underlying post-developmental neurogenesis in the mammalian brain.”

Smoke Your Troubles Away: Exploring the Effects of Death Cognitions on Cannabis Craving and Consumption.

“When reminded of their death, participants craved cannabis, even though there was no change in their conscious negative mood… Results indicate that cannabis served as a buffer and prevented death-related thoughts from entering consciousness, thus acting as a defense mechanism against death anxiety.”  http://www.ncbi.nlm.nih.gov/pubmed/25950588

http://www.thctotalhealthcare.com/category/anxiety-2/

Study: Pot May Improve Cognitive Functioning in Bipolar Disorder

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“Patients with severe psychiatric disorders actually function better in neurocognitive assessments when they have a history of marijuana use.

Patients with bipolar I disorder performed better in neurocognitive assessments when they had a history of marijuana use.”

http://www.theatlantic.com/health/archive/2012/08/study-pot-may-improve-cognitive-functioning-in-bipolar-disorder/261140/

“Cognitive and clinical outcomes associated with cannabis use in patients with bipolar I disorder”  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4408776/

European rating of drug harms.

“The present paper describes the results of a rating study performed by a group of European Union (EU) drug experts using the multi-criteria decision analysis model for evaluating drug harms.

Alcohol, heroin and crack emerged as the most harmful drugs (overall weighted harm score 72, 55 and 50, respectively). The remaining drugs had an overall weighted harm score of 38 or less, making them much less harmful than alcohol.

The outcome of this study shows that the previous national rankings based on the relative harms of different drugs are endorsed throughout the EU.

The results indicates that EU and national drug policy measures should focus on drugs with the highest overall harm, including alcohol and tobacco, whereas drugs such as cannabis and ecstasy should be given lower priority including a lower legal classification.”

http://www.ncbi.nlm.nih.gov/pubmed/25922421

http://www.thctotalhealthcare.com/category/addiction/

Inhaled cannabis reduces pain in diabetic peripheral neuropathy patients, study suggests

“A small study finds that inhaling cannabis could demonstrate a dose-dependent pain reduction in patients with diabetic peripheral neuropathy.

Researchers at the University of California, United States conducted a study in which 16 patients with painful diabetic peripheral neuropathy were given placebo, or single doses of cannabis.

These doses were either low (one per cent tetrahydrocannibinol, THC), medium (four per cent THC) or high (seven per cent THC).

Tests were first performed on baseline spontaneous pain, evoked pain and cognitive function. Subsequently, participants either inhaled the cannabis or placebo, with measurements of pain intensity and cognitive function assessed over a three-hour period.

The higher the content of THC participants inhaled, the less pain they felt. The high dose of THC had a significant effect when researchers evoked pain using foam brush and von Frey.

These are tools used to test neuropathic pain in patients – von Frey are a set of filaments that test the pain of a patients by pushing against the skin to assess when the sensation becomes painful.

Patients on the high dose of THC showed impaired performance on the neuropsychological tests, but researchers concluded the pain reduction of patients adds further evidence on the efficacy of cannabis in treating diabetic peripheral neuropathy.

The results of this study were published in the Journal of Pain and Palliative Care Pharmacology.

Earlier this month, the CBD compound in cannabis was reported by researchers as a potential treatment for diabetes.”

http://www.diabetes.co.uk/news/2015/apr/inhaled-cannabis-reduces-pain-in-diabetic-peripheral-neuropathy-patients,-study-suggests-95680845.html

“Efficacy of Inhaled Cannabis on Painful Diabetic Neuropathy.”  http://www.ncbi.nlm.nih.gov/pubmed/25843054

http://www.thctotalhealthcare.com/category/diabetes/

Critical Role of Mast Cells and Peroxisome Proliferator-Activated Receptor γ in the Induction of Myeloid-Derived Suppressor Cells by Marijuana Cannabidiol In Vivo.

“Cannabidiol (CBD) is a natural nonpsychotropic cannabinoid from marijuana (Cannabis sativa) with anti-epileptic and anti-inflammatory properties.

Effect of CBD on naive immune system is not precisely understood. In this study, we observed that administering CBD into naive mice triggers robust induction of CD11b+Gr-1+ myeloid-derived suppressor cells (MDSC) in the peritoneum, which expressed functional arginase 1, and potently suppressed T cell proliferation ex vivo…

Together, the results suggest that CBD may induce activation of PPAR-γ in mast cells leading to secretion of G-CSF and consequent MDSC mobilization.

CBD being a major component of Cannabis, our study indicates that marijuana may modulate or dysregulate the immune system by mobilizing MDSC.”

http://www.ncbi.nlm.nih.gov/pubmed/25917103

[The role of endocannabinoid system in physiological and pathological processes in the eye].

“Plant of Cannabis sativa/ marihuana except for its psychotropic effects possesses a range of pharmacological properties, that has been utilized for medical purposes over a period of millenia.

Investigations concerning biochemical mechanism of action of the main and most active pharmacological compound of Cannabis sativa, cannabinoid 9-THC, contributed to the discovery of cannabinoid receptors both in the central nervous system (CNS) and peripheral tissues, that mediated actions of this substance.

The discovery made possible identification of a new, endogenous signaling system referred to as the endocannabinoid system.

Besides cannabinoid receptors CB1 and CB2, the system includes it’s endogenic ligands (endocannabinoids) and compounds that participate in their biosynthesis and inactivation. Structure and functioning of the endocannabinoid system is conservative in all vertebrates.

It’s activation with plant, synthetic and endogenous cannabinoids has an influence on multiple physiological and pathological processes within the eye.”

http://www.ncbi.nlm.nih.gov/pubmed/19195174

Tetrahydrocannabinol (THC) interferes with conditioned retching in Suncus murinus: an animal model of anticipatory nausea and vomiting (ANV).

“Little is understood about effective countermeasures to the expression of anticipatory nausea and vomiting (ANV) in chemotherapy patients.

We present a model of ANV based on the emetic reactions of the Suncus murinus (musk shrew). Following two pairings of a novel distinctive contextual cue with the emetic effects of an injection of lithium chloride, the context acquired the potential to elicit retching in the absence of the toxin.

The expression of this conditioned retching reaction was completely suppressed by pretreatment with THC at a dose that did not suppress general activity.

This provides the first experimental evidence in support of anecdotal reports that THC suppresses ANV.”

http://www.ncbi.nlm.nih.gov/pubmed/11277577

http://www.thctotalhealthcare.com/category/nauseavomiting/

Delta-9-tetrahydrocannabinol and cannabidiol, but not ondansetron, interfere with conditioned retching reactions elicited by a lithium-paired context in Suncus murinus: An animal model of anticipatory nausea and vomiting.

“Chemotherapy patients report not only acute nausea and vomiting during the treatment itself, but also report anticipatory nausea and vomiting upon re-exposure to the cues associated with the treatment.

We present a model of anticipatory nausea based on the emetic reactions of the Suncus murinus (musk shrew). Following three pairings of a novel distinctive contextual cue with the emetic effects of an injection of lithium chloride, the context acquired the potential to elicit conditioned retching in the absence of the toxin.

The expression of this conditioned retching reaction was completely suppressed by pretreatment with each of the principal cannabinoids found in marijuana, Delta(9)-tetrahydrocannabinol or cannabidiol, at a dose that did not suppress general activity.

These results support anecdotal claims that marijuana, but not ondansetron, may suppress the expression of anticipatory nausea.”

http://www.ncbi.nlm.nih.gov/pubmed/16197970

http://www.thctotalhealthcare.com/category/nauseavomiting/