A synergistic interaction of 17-β-estradiol with specific cannabinoid receptor type 2 antagonist/inverse agonist on proliferation activity in primary human osteoblasts.

“The bone remodeling process is influenced by various factors, including estrogens and transmitters of the endocannabinoid system. In osteoblasts, cannabinoid receptors 2 (CB-2) are expressed at a much higher level compared to CB-1 receptors. Previous studies have shown that estrogens could influence CB-2 receptor expression.

In the present study, the possible interactions of a specific CB-2 agonist and a specific CB-2 antagonist/inverse agonist with 17-β-estradiol were investigated in primary human osteoblasts (HOB)…

In conclusion, for the first time a synergistic interaction between 17-β-estradiol and specific CB-2 antagonist/inverse agonist was observed in HOB.

Understanding the molecular pathways of this interaction would be of great importance in developing more efficient and safer drugs for treating or preventing bone diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26171165

CB2 receptor agonists protect human dopaminergic neurons against damage from HIV-1 gp120.

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“The global pandemic of HIV infection currently afflicts 34 million individuals, has killed over 25 million people since 1981, and is the cause of death in an estimated 1.8 million people per year.

Despite the therapeutic impact of anti-retroviral therapy, HIV-1-associated neurocognitive disorder (HAND) remains a serious threat to AIDS patients…

Synthetic cannabinoids inhibit HIV-1 expression in human microglia, suppress production of inflammatory mediators in human astrocytes, and there is substantial literature demonstrating the neuroprotective properties of cannabinoids in other neuropathogenic processes.

Based on these data, experiments were designed to test the hypothesis that synthetic cannabinoids will protect dopaminergic neurons against the toxic effects of the HIV-1 protein gp120. Using a human mesencephalic neuronal/glial culture model…

These data suggest that synthetic cannabinoids are capable of protecting human dopaminergic neurons from gp120 in a variety of ways, acting principally through the CB2 receptors and microglia.

Overall, this study confirms that gp120 is capable of damaging human dopaminergic neurons, that this damage involves human microglia, and that synthetic cannabinoids can alleviate this damage through mechanisms involving human microglia.

Thus, the results of these experiments set the stage for further studies designed to tease out the role human microglia have in the mechanisms underlying the toxic effects of HIV-1 on human dopaminergic neurons and understanding the microglial-centered mechanisms underlying the protective effects of selected synthetic cannabinoids.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3798286/

Signaling Mechanism of Cannabinoid Receptor-2 Activation-Induced β-Endorphin Release.

“Activation of cannabinoid receptor-2 (CB2) results in β-endorphin release from keratinocytes, which then acts on primary afferent neurons to inhibit nociception.

Our data also suggest that stimulation of MAPK contributes to the peripheral analgesic effect of CB2 receptor agonists.”

http://www.ncbi.nlm.nih.gov/pubmed/26108183

CB(2) cannabinoid receptor activation is cardioprotective in a mouse model of ischemia/reperfusion.

“Preventive treatment with cannabinoid agonists has been reported to reduce the infarct size in a mouse model of myocardial ischemia/reperfusion.

Here we investigated the possible cardioprotective effect of selective CB(2) cannabinoid receptor activation during ischemia.

Our data suggest that administration during ischemia reduces the infarct size in a mouse model of myocardial ischemia/reperfusion through a direct cardioprotective activity on cardiomyocytes and neutrophils.”

http://www.ncbi.nlm.nih.gov/pubmed/19162037

The cannabinoid receptor type 2 promotes cardiac myocyte and fibroblast survival and protects against ischemia/reperfusion-induced cardiomyopathy

“Post-myocardial infarction (MI) heart failure is a major public health problem in Western countries and results from ischemia/reperfusion (IR)-induced cell death, remodeling, and contractile dysfunction.

Ex vivo studies have demonstrated the cardioprotective anti-inflammatory effect of the cannabinoid type 2 (CB2) receptor agonists within hours after IR.

Herein, we evaluated the in vivo effect of CB2 receptors on IR-induced cell death, fibrosis, and cardiac dysfunction and investigated the target role of cardiac myocytes and fibroblasts… CB2 receptor activation may protect against post-IR heart failure through direct inhibition of cardiac myocyte and fibroblast death and prevention of myofibroblast activation…

In conclusion, modulation of the endocannabinoid system is emerging as a novel approach for the therapy of various inflammatory, metabolic, cardiovascular, hepatic, and neurodegenerative disorders.

CB1 receptors exert cardioprotective effects in cirrhotic rats and against doxorubicin toxicity. Pharmacological inhibition of the endocannabinoid degradative pathway, fatty acid aminohydrolase, represents a novel protective strategy against chronic inflammation, oxidative and nitrative stresses, and apoptosis associated with cardiovascular aging and atherosclerosis.

CB2 receptor activation is thought to be anti-inflammatory and involved in protective mechanisms during atherosclerosis. In addition, selective CB2 agonists protect against cerebral and hepatic IR injuries.

We demonstrated a highly protective role of CB2 receptors in post-IR cardiac remodeling, potentially related to activation of antiapoptotic, prosurvival, and antifibrogenic pathways.

Our results infer that CB2 agonists may be useful in preventing reperfusion injury in acute coronary syndrome and provide novel evidence for the pivotal role of CB2 receptors in post-IR-induced cardiomyopathy.”

http://www.fasebj.org/content/23/7/2120.long

The endocannabinoid-CB2 receptor axis protects the ischemic heart at the early stage of cardiomyopathy.

“Ischemic heart disease is associated with inflammation, interstitial fibrosis and ventricular dysfunction prior to the development of heart failure.

Endocannabinoids and the cannabinoid receptor CB2 have been claimed to be involved, but their potential role in cardioprotection is not well understood. We therefore explored the role of the cannabinoid receptor CB2 during the initial phase of ischemic cardiomyopathy development prior to the onset of ventricular dysfunction or infarction.

… the endocannabinoid-CB2 receptor axis plays a key role in cardioprotection during the initial phase of ischemic cardiomyopathy development.”

http://www.ncbi.nlm.nih.gov/pubmed/24980781

CB2R orchestrates fibrogenesis through regulation of inflammatory response during the repair of skeletal muscle contusion.

“Skeletal muscle injuries repair typically is an overlapping event between inflammation and tissue repair.

Our previous study has demonstrated that activation of cannabinoid receptor type 2 (CB2R) alleviates fibrosis in the repair of rat skeletal muscle contusion. Meanwhile, accumulated data show that CB2R stimulation exerts anti-inflammatory property in sepsis and cystitis…

In this study, we used selective agonist or antagonist of CB2R to observe the role of CB2R on inflammation and fibrogenesis during the repair of contused skeletal muscles in rats…

Our study demonstrated that CB2R orchestrates fibrogenesis through regulation of inflammatory response during the repair of skeletal muscle contusion.”

http://www.ncbi.nlm.nih.gov/pubmed/26097533

 

Anandamide, Acting via CB2 Receptors, Alleviates LPS-Induced Neuroinflammation in Rat Primary Microglial Cultures.

“Microglial activation is a polarized process divided into potentially neuroprotective phenotype M2 and neurotoxic phenotype M1, predominant during chronic neuroinflammation.

Endocannabinoid system provides an attractive target to control the balance between microglial phenotypes.

Anandamide as an immune modulator in the central nervous system acts via not only cannabinoid receptors (CB1 and CB2) but also other targets (e.g., GPR18/GPR55).

In summary, we showed that the endocannabinoid system plays a crucial role in the management of neuroinflammation by dampening the activation of an M1 phenotype. This effect was primarily controlled by the CB2 receptor, although functional cross talk with GPR18/GPR55 may occur.”

http://www.ncbi.nlm.nih.gov/pubmed/26090232

Cannabinoid CB2 Receptors in a Mouse Model of Aβ Amyloidosis: Immunohistochemical Analysis and Suitability as a PET Biomarker of Neuroinflammation.

“In Alzheimer’s disease (AD), one of the early responses to Aβ amyloidosis is recruitment of microglia to areas of new plaque. Microglial receptors such as cannabinoid receptor 2 (CB2) might be a suitable target for development of PET radiotracers that could serve as imaging biomarkers of Aβ-induced neuroinflammation…

The presence of CB2 immunoreactivity in neurons does not likely contribute to the enhanced CB2 PET signal in amyloid-bearing mice due to a lack of significant neuronal loss in this model. However, significant loss of neurons as seen at late stages of AD might decrease the CB2 PET signal due to loss of neuronally-derived CB2.

Thus this study in mouse models of AD indicates that a CB2-specific radiotracer can be used as a biomarker of neuroinflammation in the early preclinical stages of AD, when no significant neuronal loss has yet developed.”

http://www.ncbi.nlm.nih.gov/pubmed/26086915

http://www.thctotalhealthcare.com/category/alzheimers-disease-ad/

In vivo inflammation imaging using a CB2R-targeted near infrared fluorescent probe.

“Chronic inflammation is considered as a critical cause of a host of disorders, such as cancer, rheumatoid arthritis, atherosclerosis, and neurodegenerative diseases…

Imaging tools that can specifically target inflammation are therefore important to help reveal the role of inflammation in disease progression, and allows for developing new therapeutic strategies to ultimately improve patient care.

The purpose of this study was to develop a new in vivo inflammation imaging approach by targeting the cannabinoid receptor type 2 (CB2R), an emerging inflammation biomarker, using a unique near infrared (NIR) fluorescent probe…

The combined evidence indicates that NIR760-mbc94 is a promising inflammation imaging probe. Moreover, in vivo CB2R-targeted fluorescence imaging may have potential in the study of inflammation-related diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26069858