The role of CB1 in immune modulation by cannabinoids.

“There is clear evidence that CB(2), historically referred to as the peripheral cannabinoid receptor, mediates many of the immune modulatory effects of cannabinoids.

 However, cannabinoid receptors cannot be classified simply as central or peripheral since CB(2) has been shown to play a role in the central nervous system (CNS) and CB(1) mediates many immune system effects. Although Cnr1 mRNA and CB(1) protein expression is lower than Cnr2 mRNA or CB(2) protein expression in cells of the immune system, several studies have shown direct modulation of immune function via CB(1) by endogenous and exogenous cannabinoids in T cells, innate cells, and to a lesser extent, B cells.

In addition, indirect, but CB(1)-dependent, mechanisms of immune modulation exist. In fact, the mechanism by which cannabinoids attenuate neuroinflammation via CB(1) is likely a combination of immune suppression and neuroprotection.

 Although many studies demonstrate that agonists for CB(1) are immune suppressive and anti-inflammatory, CB(1) antagonists also exhibit anti-inflammatory properties. Overall, the data demonstrate that many of the immune modulatory effects of cannabinoids are mediated via CB(1).”

http://www.ncbi.nlm.nih.gov/pubmed/23261520

Activation of cannabinoid receptor 2 attenuates leukocyte-endothelial cell interactions and blood-brain barrier dysfunction under inflammatory conditions.

“Previous studies have shown that modulation of the receptor-mediated cannabinoid system during neuroinflammation can produce potent neuroprotective and anti-inflammatory effects

…Together, these results suggest that pharmacological CB2R ligands offer a new strategy for BBB protection during neuroinflammation.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3325902/

Emerging role of the cannabinoid receptor CB2 in immune regulation: therapeutic prospects for neuroinflammation.

“There is now a large body of data indicating that the cannabinoid receptor type 2 (CB2) is linked to a variety of immune events. This functional relevance appears to be most salient in the course of inflammation, a process during which there is an increased number of receptors that are available for activation. Studies aimed at elucidating signal transduction events resulting from CB2 interaction with its native ligands, and of the role of exogenous cannabinoids in modulating this process, are providing novel insights into the role of CB2 in maintaining a homeostatic immune balance within the host. Furthermore, these studies suggest that the CB2 may serve as a selective molecular target for therapeutic manipulation of untoward immune responses, including those associated with a variety of neuropathies that exhibit a hyperinflammatory component.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2768535/

Researchers Have Discovered Synthetic Agents Used To Treat HIV Inflammation – Medical News Today

“HIV can cause serious inflammation, regardless of drug therapy, as it develops slowly in immune cells called macrophages. However, new research conducted at the Temple University School of Medicine’s Department of Pathology and Laboratory Medicine and Center for Substance Abuse Research (CSAR) has just found that there are synthetic agents with anti-inflammatory properties, related to the active ingredient in cannabis, THC (tetrahydrocannabinol) which could limit and treat the chronic inflammation.

These findings suggest that CB2 agonists could be used along with antiretroviral drugs which could lead to a new form of therapy for HIV/AIDS.

It also suggests that the human immune system itself could be used to fight off the HIV infection.

According to Persidsky: “Our study suggests that the body’s own natural defenses can be made more powerful to fight some of the worst symptoms of HIV.”

Stimulating CB2 receptors could also be applied for treating other infections.”

More: http://www.medicalnewstoday.com/articles/260152.php

Cannabinoid Receptor 2 Protects against Acute Experimental Sepsis in Mice.

“The systemic inflammatory response syndrome can be self-limited or can progress to severe sepsis and septic shock. Despite significant advances in the understanding of the molecular and cellular mechanisms of septic shock, it is still one of the most frequent and serious problems confronting clinicians in the treatments. And the effects of cannabinoid receptor 2 (CB2R) on the sepsis still remain undefined.

 The present study was aimed to explore the role and mechanism of CB2R in acute sepsis model of mice. Here, we found that mice were more vulnerable for lipopolysaccharide- (LPS-) induced death and inflammation after CB2R deletion (CB2R(-/-)). CB2R agonist, GW405833, could significantly extend the survival rate and decrease serum proinflammatory cytokines in LPS-treated mice. GW405833 dose-dependently inhibits proinflammatory cytokines release in splenocytes and peritoneal macrophages as well as splenocytes proliferation, and these effects were partly abolished in CB2R(-/-) splenocytes but completely abolished in CB2R(-/-) peritoneal macrophages. Further studies showed that GW405833 inhibits LPS-induced phosphorylation of ERK1/2 and STAT3 and blocks I κ B α degradation and NF- κ B p65 nuclear translocation in macrophages.

 All data together showed that CB2R provides a protection and is a potential therapeutic target for the sepsis.”

http://www.ncbi.nlm.nih.gov/pubmed/23781122

Expression, surface immobilization, and characterization of functional recombinant cannabinoid receptor CB2.

Human peripheral cannabinoid receptor CB2, a G protein-coupled receptor (GPCR) involved in regulation of immune response has become an important target for pharmaceutical drug development.

 Structural and functional studies on CB2 may benefit from immobilization of the purified and functional receptor onto a suitable surface at a controlled density and, preferably in a uniform orientation. The goal of this project was to develop a generic strategy for preparation of functional recombinant CB2 and immobilization at solid interfaces. Expression of CB2 as a fusion with Rho-tag (peptide composed of the last nine amino acids of rhodopsin) in E. coli was evaluated in terms of protein levels, accessibility of the tag, and activity of the receptor. The structural integrity of CB2 was tested by ligand binding to the receptor solubilized in detergent micelles, captured on tag-specific monoclonal 1D4 antibody-coated resin. Highly pure and functional CB2 was obtained by sequential chromatography on a 1D4- and Ni-NTA- resin and its affinity to the 1D4 antibody characterized by surface plasmon resonance (SPR). Either the purified receptor or fusion CB2 from the crude cell extract was captured onto a 1D4 -coated CM4 chip (Biacore) in a quantitative fashion at uniform orientation as demonstrated by the SPR signal. Furthermore, the accessibility of the extracellular surface of immobilized CB2 and the affinity of interaction with a novel monoclonal antibody NAA-1 was studied by SPR.

 In summary, we present an integral strategy for purification, surface immobilization, ligand- and antibody binding studies of functional cannabinoid receptor CB2.”

http://www.ncbi.nlm.nih.gov/pubmed/23777860

Synthetic Compounds From Marijuana Appear to Fight HIV

“Synthetic anti-inflammatory compounds derived from the active ingredient of marijuana appear to show potential as anti-HIV agents, Wired.co.uk reports. Publishing their findings in the Journal of Leukocyte Biology, researchers from Temple University School of Medicine’s Department of Pathology and Laboratory Medicine and Center for Substance Abuse Research (CSAR) studied synthetic derivations of THC, or tetrahydrocannabinol, a key chemical compound in marijuana, in cultures of HIV-infected cells.

Cannabinoids, which are the primary active compounds in marijuana, bind to proteins called CB2 receptors on the surface of macrophage immune cells. The CB2 site may play a role in reducing inflammation in the central nervous system, which is a major concern for people living with HIV, even those whose virus is fully suppressed thanks to antiretrovirals (ARVs). It is the CB1 receptors, mostly found in neurons in the brain, however, that cause marijuana’s psychoactive effects. So synthetic THC that has been developed to bind only to CB2 receptors should not make people stoned.

It is believed that macrophage cells, which are found throughout the body, are a major component of the HIV reservoir and are probably the first cells infected after sexual transmission of the virus.

Using a non-clinical cell model, the investigators treated HIV-infected macrophages with one of three different synthetic compounds that bind to CB2. By periodically measuring the activity of the enzyme reverse transcriptase, which HIV needs to replicate itself, the investigators concluded after a seven-day period that all three compounds fought HIV replication.

The findings suggest that these “CB2 agonists” could be a potential addition to ARV therapy, and also that the human immune system could be prompted to fight the virus using similar mechanisms.”

http://www.aidsmeds.com/articles/pot_CB2_1667_23905.shtml

Compounds That Stimulate The Cannabinoid Type 2 Receptor In White Blood Cells Can Weaken HIV-1 Infection – MedicalNewsToday

“A new use for compounds related in composition to the active ingredient in marijuana may be on the horizon: a new research report published in the Journal of Leukocyte Biology shows that compounds that stimulate the cannabinoid type 2 (CB2) receptor in white blood cells, specifically macrophages, appear to weaken HIV-1 infection. The CB2 receptor is the molecular link through which the pharmaceutical properties of cannabis are manifested. Diminishing HIV-1 infection in this manner might make current anti-viral therapies more effective and provide some protection against certain HIV-1 complications.”

More:  http://www.medicalnewstoday.com/releases/259885.php

Synthetic derivatives of THC may weaken HIV-1 infection to enhance antiviral therapies – MedicalXpress

“A new use for compounds related in composition to the active ingredient in marijuana may be on the horizon: a new research report published in the Journal of Leukocyte Biology shows that compounds that stimulate the cannabinoid type 2 (CB2) receptor in white blood cells, specifically macrophages, appear to weaken HIV-1 infection. The CB2 receptor is the molecular link through which the pharmaceutical properties of cannabis are manifested. Diminishing HIV-1 infection in this manner might make current anti-viral therapies more effective and provide some protection against certain HIV-1 complications.

“The synthetic compounds we used in our study may show promise in helping the body fight HIV-1 infection,'” said Yuri Persidsky, M.D., Ph.D., a researcher involved in the work from the Department of Pathology and Laboratory Medicine at Temple University School of Medicine in Philadelphia, PA. “As compounds like these are improved further and made widely available, we will continue to explore their potential to fight other viral diseases that are notoriously difficult to treat.”

To make this discovery, scientists used a cell culture model to infect human macrophages with HIV-1 and added synthetic compounds similar to the active ingredient in marijuana to activate the CB2 receptor. At different times during the infection, samples from the culture were taken to see if the replication of the HIV virus was decreased. The researchers observed diminished HIV growth and a possible protective effect from some HIV-1 complications.

“HIV/AIDS has posed one of the most significant health challenges in modern medicine,” said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. “Recent high profile vaccine failures mean that all options need to be on the table to prevent or treat this devastating infection. Research on the role of cannabinoid type 2 receptors and viral infection may one day allow targeting these receptors to be part of combination therapies that use exploit multiple weaknesses of the virus simultaneously.””

http://medicalxpress.com/news/2013-04-synthetic-derivatives-thc-weaken-hiv-.html

Scientists weaken HIV infection in immune cells using synthetic agents – MedicalXpress

“HIV, the virus that causes AIDS, is notorious for hiding within certain types of cells, where it reproduces at a slowed rate and eventually gives rise to chronic inflammation, despite drug therapy. But researchers at Temple University School of Medicine’s Department of Pathology and Laboratory Medicine and Center for Substance Abuse Research (CSAR) recently discovered that synthetic anti-inflammatory substances distantly related to the active ingredient of marijuana may be able to take the punch out of HIV while inside one of its major hideouts – immune cells known as macrophages.

The results suggest that selective CB2 agonists could potentially be used in tandem with existing antiretroviral drugs, opening the door to the generation of new drug therapies for HIV/AIDS. The data also support the idea that the human immune system could be leveraged to fight HIV infection.

“Our study suggests that the body’s own natural defenses can be made more powerful to fight some of the worst symptoms of HIV,” Persidsky explained. He also noted that stimulating CB2 receptors in white blood cells could produce similar benefits against other viral infections.

 The most promising compounds are those derived from THC (tetrahydrocannabinol), the main active substance in cannabis.”

More: http://medicalxpress.com/news/2013-05-scientists-weaken-hiv-infection-immune.html