CB2 receptors regulate natural killer cells that limit allergic airway inflammation in a murine model of asthma.

Image result for allergy journal

“Allergic asthma is a chronic airway inflammatory disease involving the complementary actions of innate and adaptive immune responses.

Endogenously generated cannabinoids, acting via CB2 receptors play important roles in both homeostatic and inflammatory processes. However, the contribution of CB2-acting eicosanoids to the innate events preceding sensitization to the common house dust mite (HDM) allergen, remain to be elucidated. We investigated the role of CB2 activation during allergen-induced pulmonary inflammation and NK cell effector function.

CONCLUSIONS:

Collectively, these results reveal that CB2 activation is crucial in regulating pulmonary NK cell function, and suggest that NK cells serve to limit ILC2 activation and subsequent allergic airway inflammation. CB2 inhibition may present an important target to modulate NK cell response during pulmonary inflammation.”

https://www.ncbi.nlm.nih.gov/pubmed/27992060

Δ9-Tetrahydrocannabinol Reverses TNFα-induced Increase in Airway Epithelial Cell Permeability through CB2 Receptors.

Image result for Biochem Pharmacol

“Despite pharmacological treatment, bronchial hyperresponsiveness continues to deteriorate as airway remodelling persists in airway inflammation.

Previous studies have demonstrated that the phytocannabinoid Δ9-tetrahydrocannabinol (THC) reverses bronchoconstriction with an anti-inflammatory action.

The aim of this study was to investigate the effects of THC on bronchial epithelial cell permeability after exposure to the pro-inflammatory cytokine, TNFα. Calu-3 bronchial epithelial cells were cultured at air-liquid interface.

These data indicate that THC prevents cytokine-induced increase in airway epithelial permeability through CB2 receptor activation.

This highlights that THC, or other cannabinoid receptor ligands, could be beneficial in the prevention of inflammation-induced changes in airway epithelial cell permeability, an important feature of airways diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/27641813

The effect of cannabinoids on dinitrofluorobenzene-induced experimental asthma in mice.

“Cannabinoids have anti-inflammatory effects and can produce bronchodilation in the airways.

We have investigated the effects of cannabinoids on tracheal hyperreactivity and airway inflammation in dinitrofluorobenzene (DNFB)-induced experimental non-atopic asthma in mice.

These results show that cannabinoid CB1 receptor agonist can prevent tracheal hyperreactivity to 5-HT in DNFB-induced non-atopic asthma in mice.”

http://www.ncbi.nlm.nih.gov/pubmed/27216000

ENDOCANNABINOID SYSTEM: A multi-facet therapeutic target.

Image result for Curr Clin Pharmacol.

“Cannabis sativa is also popularly known as marijuana. It is being cultivated and used by man for recreational and medicinal purposes from many centuries.

Study of cannabinoids was at bay for very long time and its therapeutic value could not be adequately harnessed due to its legal status as proscribed drug in most of the countries.

The research of drugs acting on endocannabinoid system has seen many ups and down in recent past. Presently, it is known that endocannabinoids has role in pathology of many disorders and they also serve “protective role” in many medical conditions.

Several diseases like emesis, pain, inflammation, multiple sclerosis, anorexia, epilepsy, glaucoma, schizophrenia, cardiovascular disorders, cancer, obesity, metabolic syndrome related diseases, Parkinson’s disease, Huntington’s disease, Alzheimer’s disease and Tourette’s syndrome could possibly be treated by drugs modulating endocannabinoid system.

Presently, cannabinoid receptor agonists like nabilone and dronabinol are used for reducing the chemotherapy induced vomiting. Sativex (cannabidiol and THC combination) is approved in the UK, Spain and New Zealand to treat spasticity due to multiple sclerosis. In US it is under investigation for cancer pain, another drug Epidiolex (cannabidiol) is also under investigation in US for childhood seizures. Rimonabant, CB1 receptor antagonist appeared as a promising anti-obesity drug during clinical trials but it also exhibited remarkable psychiatric side effect profile. Due to which the US Food and Drug Administration did not approve Rimonabant in US. It sale was also suspended across the EU in 2008.

Recent discontinuation of clinical trial related to FAAH inhibitor due to occurrence of serious adverse events in the participating subjects could be discouraging for the research fraternity. Despite of some mishaps in clinical trials related to drugs acting on endocannabinoid system, still lot of research is being carried out to explore and establish the therapeutic targets for both cannabinoid receptor agonists and antagonists.

One challenge is to develop drugs that target only cannabinoid receptors in a particular tissue and another is to invent drugs that acts selectively on cannabinoid receptors located outside the blood brain barrier. Besides this, development of the suitable dosage forms with maximum efficacy and minimum adverse effects is also warranted.

Another angle to be introspected for therapeutic abilities of this group of drugs is non-CB1 and non-CB2 receptor targets for cannabinoids.

In order to successfully exploit the therapeutic potential of endocannabinoid system, it is imperative to further characterize the endocannabinoid system in terms of identification of the exact cellular location of cannabinoid receptors and their role as “protective” and “disease inducing substance”, time-dependent changes in the expression of cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27086601

Stimulation of cannabinoid CB1 receptors prevents nerve-mediated airway hyperreactivity in NGF-induced inflammation in mouse airways.

“In the present study, we tested the hypothesis that cannabinoids have both acute and chronic modulatory effects on nerve-mediated contractions in NGF-induced airway inflammation.

This study shows that stimulation of cannabinoid CB1 receptors modifies the increase of neuronal activity and density in NGF-induced airway inflammation and directly inhibits cholinergic contractions in the airways by a presynaptic mechanism.

These findings indicate a protective role of CB1 receptors in airway inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/26896777

Biomedical benefits of cannabinoids?

“Cannabinoids appear to be of therapeutic value as antiemetics, antispasmodics, analgesics and appetite stimulants and may have potential uses in epilepsy, glaucoma and asthma.

This paper reviews the clinical trials which have been carried out with cannabinoids including Δ⁹-tetrahydrocannabinol (THC) and synthetic cannabinoids such as nabilone and levonantradol, and discusses the advantages and adverse effects of cannabinoids in clinical use.

The place of cannabinoids in modern medicine remains to be properly evaluated, but present evidence suggests that they could be valuable, particularly as adjuvants, for symptom control in a range of conditions for which standard drugs are not fully satisfactory.”

Activation of cannabinoid receptors prevents antigen-induced asthma-like reaction in guinea pigs.

“In this study we evaluated the effects of the CB1/CB2 cannabinoid receptor agonist on antigen-induced asthma-like reaction in sensitized guinea pigs…

These findings suggest that targeting cannabinoid receptors could be a novel preventative therapeutic strategy in asthmatic patients.”

http://www.ncbi.nlm.nih.gov/pubmed/18266975

Evaluation of Serum Cytokines Levels and the Role of Cannabidiol Treatment in Animal Model of Asthma.

Image result for hindawi

“Asthma represents a public health problem and traditionally is classified as an atopic disease, where the allergen can induce clinical airway inflammation, bronchial hyperresponsiveness, and reversible obstruction of airways.

Studies have demonstrated the presence of T-helper 2 lymphocytes in the lung of patients with asthma. These cells are involved in cytokine production that regulates immunoglobulin synthesis.

Recognizing that T cell interaction with antigens/allergens is key to the development of inflammatory diseases, the aim of this study is to evaluate the anti-inflammatory potential of cannabidiol (CBD) in this setting.

CBD treatment was able to decrease the serum levels of all analyzed cytokines except for IL-10 levels.

CBD seems to be a potential new drug to modulate inflammatory response in asthma.” http://www.ncbi.nlm.nih.gov/pubmed/26101464

“In conclusion, we here demonstrate that the administration of CBD in an animal model of asthma could blunt the serum cytokine response to OVA in sensitized animals. These effects suggest a potential for a new asthma treatment since CBD controls the exaggerated inflammatory response observed in this model.” https://www.hindawi.com/journals/mi/2015/538670/

Antihistaminic action of (–)-trans-delta 9-tetrahydrocannabinol.

“THC has an antagonistic effect against histamine on the isolated perfused guinea-pig lung and rabbit kidney. This antagonism seems to be a competitive one at the concentrations used and interacts with histamine at H1-receptors. THC also antagonizes the effect of acetylcholine, PGE2, angiotensis II and histamine in the isolated continuously superfused guinea-pig ileum by a non-competitive manner. The antagonism between THC and histamine on the isolated superfused rabbit aortic strips was found to be highly specific, since 100% relaxation was obtained when the muscle contracted by histamine but not by the equipotent doses of angiotensin II and noradrenaline. THC also causes a significant increase in survival time of guinea-pigs when the animals were exposed to histamine aerosol. These results indicate a specific antagonism of THC against histamine in the preparations used in this investigation.”

http://www.ncbi.nlm.nih.gov/pubmed/239651

“antihistaminic /an·ti·his·ta·min·ic/ (-his-tah-min´ik)

1. counteracting the effect of histamine.
Tending to neutralize or antagonize the action of histamine or inhibit its production in the body.

Cannabinoid-induced apoptosis in immune cells as a pathway to immunosuppression.

Fig. 1

“Cannabinoids are a group of compounds found in the marijuana plant (Cannabis sativaL.). Marijuana has been used both for recreational and medicinal purposes for several centuries.

Cannabinoids have been shown to be effective in the treatment of nausea and vomiting associated with cancer chemotherapy, anorexia and cachexia seen in HIV/AIDS patients, as well as neuropathic pain, and spasticity in multiple sclerosis.

More recently, the anti-inflammatory properties of cannabinoids are drawing significant attention. In the last 15 years, studies with marijuana cannabinoids led to the discovery of cannabinoid receptors (CB1 and CB2) and their endogenous ligands, which make up what is known as the endocannabinoid system.

Cannabinoids are a group of compounds present in Cannabis plant (Cannabis sativa L.). They mediate their physiological and behavioral effects by activating specific cannabinoid receptors. With the recent discovery of the cannabinoid receptors (CB1 and CB2) and the endocannabinoid system, research in this field has expanded exponentially.

Cannabinoids have been shown to act as potent immunosuppressive and anti-inflammatory agents and have been shown to mediate beneficial effects in a wide range of immune-mediated diseases such as multiple sclerosis, diabetes, septic shock, rheumatoid arthritis, and allergic asthma.

Cannabinoid receptor 1 (CB1) is mainly expressed on the cells of the central nervous system as well as in the periphery. In contrast, cannabinoid receptor 2 (CB2) is predominantly expressed on immune cells. The precise mechanisms through which cannabinoids mediate immunosuppression is only now beginning to be understood…

In this review, we will focus on apoptotic mechanisms of immunosuppression mediated by cannabinoids on different immune cell populations and discuss how activation of CB2 provides a novel therapeutic modality against inflammatory and autoimmune diseases as well as malignancies of the immune system, without exerting the untoward psychotropic effects…

…cannabinoids do induce apoptosis in immune cells, alleviating inflammatory responses and protecting the host from acute and chronic inflammation.

The cumulative effect of cannabinoids on all cell populations of the immune system can be beneficial, when there is a need for immune suppression.

For example, in patients with autoimmune diseases such as multiple sclerosis, arthritis and lupus, or in those with septic shock, where the disease is caused by activated immune cells, targeting the immune cells via CB2 agonists may trigger apoptosis and act as anti-inflammatory therapy.

CB2 select agonists are not psychoactive and because CB2 is expressed primarily in immune cells, use of CB2 agonists could provide a novel therapeutic modality against autoimmune and inflammatory diseases.

In addition to the use of exogenous cannabinoids, in vivo manipulation of endocannabinoids may also offer novel treatment opportunities against cancer and autoimmune diseases.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3005548/