Inhibition of inflammatory hyperalgesia by activation of peripheral CB2 cannabinoid receptors.

“BACKGROUND:

Cannabinoid receptor agonists inhibit inflammatory hyperalgesia in animal models. Nonselective cannabinoid receptor agonists also produce central nervous system (CNS) side effects. Agonists selective for CB2 cannabinoid receptors, which are not found in the CNS, do not produce the CNS effects typical of nonselective cannabinoid receptor agonists but do inhibit acute nociception. The authors used the CB2 receptor-selective agonist AM1241 to test the hypothesis that selective activation of peripheral CB2 receptors inhibits inflammatory hyperalgesia.”

“CONCLUSIONS:

Local, peripheral CB2 receptor activation inhibits inflammation and inflammatory hyperalgesia. These results suggest that peripheral CB2 receptors may be an appropriate target for eliciting relief of inflammatory pain without the CNS effects of nonselective cannabinoid receptor agonists.”

http://www.ncbi.nlm.nih.gov/pubmed/14508331

CB2 cannabinoid receptor-mediated peripheral antinociception.

  “Cannabinoid receptor agonists diminish responses to painful stimuli. Extensive evidence implicates the CB(1) receptor in the production of antinociception. However, the capacity of CB(2) receptors, which are located outside the central nervous system (CNS), to produce antinociception is not known. Using AM1241, a CB(2) receptor-selective agonist, we demonstrate that CB(2) receptors produce antinociception to thermal stimuli… Peripheral antinociception without CNS effects is consistent with the peripheral distribution of CB(2) receptors. CB(2) receptor agonists may have promise clinically for the treatment of pain without CNS cannabinoid side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/11514083

CB2 cannabinoid receptor activation produces antinociception by stimulating peripheral release of endogenous opioids.

  “CB(2) cannabinoid receptor-selective agonists are promising candidates for the treatment of pain. CB(2) receptor activation inhibits acute, inflammatory, and neuropathic pain responses but does not cause central nervous system (CNS) effects, consistent with the lack of CB(2) receptors in the normal CNS…

We have demonstrated that antinociception produced by CB2 receptor-selective agonists may be mediated by stimulation of β-endorphin release from CB2-expressing cells. The β-endorphin released thus appears to act at μ-opioid receptors, probably on the terminals of primary afferent neurons, to produce peripheral antinociception. This mechanism allows for the local release of endogenous opioids limited to sites where CB2 receptors are present, thereby leading to anatomical specificity of opioid effects. In this way, CB2 receptor activation may produce peripheral antinociception without CNS side effects.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC549497/

Involvement of peripheral cannabinoid and opioid receptors in β-caryophyllene-induced antinociception.

“BACKGROUND:

  β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis. The present study investigated the contribution of peripheral cannabinoid (CB) and opioid systems in the antinociception produced by intraplantar (i.pl.) injection of BCP. The interaction between peripheral BCP and morphine was also examined.”

“CONCLUSIONS:

The present results demonstrate that antinociception produced by i.pl. BCP is mediated by activation of CB(2) receptors, which stimulates the local release from keratinocytes of the endogenous opioid β-endorphin. The combined injection of morphine and BCP may be an alternative in treating chemogenic pain.”

http://www.ncbi.nlm.nih.gov/pubmed/23138934

Cannabinoid 2 receptor induction by IL-12 and its potential as a therapeutic target for the treatment of anaplastic thyroid carcinoma.

“Anaplastic thyroid carcinoma is the most aggressive type of thyroid malignancies…”

 “These data suggest that CB2 overexpression may contribute to the regression of human anaplastic thyroid tumor… Given that cannabinoids have shown antitumor effects in many types of cancer models, CB2 may be a viable therapeutic target for the treatment of anaplastic thyroid carcinoma.”

http://www.ncbi.nlm.nih.gov/pubmed/18197164

Anti-proliferative and anti-angiogenic effects of CB2R agonist (JWH-133) in non-small lung cancer cells (A549) and human umbilical vein endothelial cells: an in vitro investigation.

 

“Non-small cell lung cancer has one of the highest mortality rates among cancer-suffering patients. It is well known that the unwanted psychotropic effects of cannabinoids (CBs) are mediated via the CB(1) receptor (R), and selective targeting of the CB(2)R would thus avoid side effects in cancer treatment…

the aim of our study was to evaluate the effect of selective CB(2)R agonist, JWH-133, on A549 cells (non-small lung cancer) and human umbilical vein endothelial cells (HUVECs)…

The present study demonstrates the in vitro anti-proliferative and anti-angiogenic potential of CB(2)R agonist, JWH-133, in nonsmall lung cancer cells and HUVECs.

Our results generate a rationale for further in vivo efficacy studies with this compound in preclinical cancer models.”

http://www.ncbi.nlm.nih.gov/pubmed/22578958

Cannabinoid receptor type 2 activation induces a microglial anti-inflammatory phenotype and reduces migration via MKP induction and ERK dephosphorylation

“Cannabinoid receptor type 2 (CBR2) inhibits microglial reactivity through a molecular mechanism yet to be elucidated. We hypothesized that CBR2 activation induces an anti-inflammatory phenotype in microglia by inhibiting extracellular signal-regulated kinase (ERK) pathway, via mitogen-activated protein kinase-phosphatase (MKP) induction. MKPs regulate mitogen activated protein kinases, but their role in the modulation of microglial phenotype is not fully understood.”

“Our results uncover a cellular microglial pathway triggered by CBR2 activation. These data suggest that the reduction of pro-inflammatory factors and microglial migration via MKP-3 induction is part of the mechanism of action of CBR2 agonists. These findings may have clinical implications for further drug development.”

“In summary, our current results uncovered a cellular mechanism of action of CBR2 agonists that produces a microglial anti-inflammatory phenotype, which may modulate microglial motility in vivo. We identified MKP-3 and microglial migration as potential new targets for drug development. The clinical utility of CBR2 agonists is supported by their analgesic efficacy and their lack of neurological side effects in animal models of postoperative or neuropathic pain.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2704199/

Selective activation of cannabinoid CB(2) receptors suppresses spinal fos protein expression and pain behavior in a rat model of inflammation.

“Activation of cannabinoid CB(2) receptors attenuates thermal nociception in untreated animals while failing to produce centrally mediated effects such as hypothermia and catalepsy. The present study was conducted to test the hypothesis that activation of CB(2) in the periphery suppresses the development of inflammatory pain as well as inflammation-evoked neuronal activity at the level of the CNS…”

“These data provide evidence that actions at cannabinoid CB(2) receptors are sufficient to suppress inflammation-evoked neuronal activity at rostral levels of processing in the spinal dorsal horn…”

http://www.ncbi.nlm.nih.gov/pubmed/12809695

Involvement of cannabinoid CB2 receptor in alcohol preference in mice and alcoholism in humans.

Abstract

“We tested if cannabinoid type 2 receptor (CB2) in the central nervous system plays a role in alcohol abuse/dependence in animal model and then examined an association between the CB2 gene polymorphism and alcoholism in human. Mice experiencing more alcohol preference by drinking showed reduced Cb2 gene expression, whereas mice with little preference showed no changes of it in ventral midbrain. Alcohol preference in conjunction with chronic mild stress were enhanced in mice treated with CB2 agonist JWH015 when subjected to chronic stress, whereas antagonist AM630 prevented development of alcohol preference. There is an association between the Q63R polymorphism of the CB2 gene and alcoholism in a Japanese population (P=0.007; odds ratio 1.25, 95% CI, (1.06-1.47)). CB2 under such environment is associated with the physiologic effects of alcohol and CB2 antagonists may have potential as therapies for alcoholism.”

http://www.ncbi.nlm.nih.gov/pubmed/17189959

Cannabinoid CB1 receptor antagonists as potential pharmacotherapies for drug abuse disorders.

Abstract

“Since the discovery of the cannabinoid CB1 receptor (CB1R) in 1988, and subsequently of the CB2 receptor (CB2R) in 1993, there has been an exponential growth of research investigating the functions of the endocannabinoid system. The roles of CB1Rs have been of particular interest to psychiatry because of their selective presence within the CNS and because of their association with brain-reward circuits involving mesocorticolimbic dopamine systems. One potential role that has become of considerable focus is the ability of CB1Rs to modulate the effects of the drugs of abuse. Many drugs of abuse elevate dopamine levels, and the ability of CB1R antagonists or inverse agonists to modulate these elevations has suggested their potential application as pharmacotherapies for treating drug abuse disorders. With the identification of the selective CB1R antagonist, rimonabant, in 1994, and subsequently of other CB1R antagonists, there has been a rapid expansion of research investigating their ability to modulate the effects of the drugs of abuse. This review highlights some of the preclinical and clinical studies that have examined the effects of CB1R antagonists under conditions potentially predictive of their therapeutic efficacy as treatments for drug abuse disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/19367507