Cannabinoids and autoimmune diseases: A systematic review.

Posted on February 17, 2016 by David

“Cannabinoids have shown to have a variety effects on body systems. Through CB1 and CB2 receptors, amongst other, they exert an effect by modulating neurotransmitter and cytokine release.

Current research in the role of cannabinoids in the immune system shows that they possess immunosuppressive properties. They can inhibit proliferation of leucocytes, induce apoptosis of T cells and macrophages and reduce secretion of pro-inflammatory cytokines.

In mice models, they are effective in reducing inflammation in arthritis, multiple sclerosis, have a positive effect on neuropathic pain and in type 1 diabetes mellitus.

They are effective as treatment for fibromyalgia and have shown to have anti-fibrotic effect in scleroderma.

Studies in human models are scarce and not conclusive and more research is required in this field.

Cannabinoids can be therefore promising immunosuppressive and anti-fibrotic agents in the therapy of autoimmune disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/26876387

http://www.thctotalhealthcare.com/category/autoimmune-disease/

Attenuation of cue-induced reinstatement of nicotine seeking by URB597 through cannabinoid CB1 receptor in rats.

Posted on February 13, 2016 by David

“The endocannabinoid system is composed of endocannabinoids (such as anandamide), their target receptors (CB₁ and CB₂ receptors, CB₁Rs and CB₂Rs), the enzymes that degrade them (fatty-acid-amide-hydrolase (FAAH) for anandamide), and an endocannabinoid transporter. FAAH inhibition has been recently identified as having a critical involvement in behaviors related to nicotine addiction and has been shown to reduce the effect of nicotine on the mesolimbic dopaminergic system via CB₁R and peroxisome proliferator-activated receptor alpha (PPARα). Thus, inhibition of FAAH may represent a novel strategy for smoking cessation, but its mechanism of action on relapse to nicotine seeking is still unknown.

OBJECTIVE:

The study aims to explore the mechanism of action of the inhibitor of FAAH activity, URB597, on relapse to nicotine seeking by evaluating the effect of the CB₁R, CB₂R, and PPARα antagonists on the attenuating effect of URB597 on cue-induced reinstatement of nicotine seeking in rats.

RESULTS:

URB597 reduced cue-induced reinstatement of nicotine seeking, an effect that was reversed by the CB₁R antagonist rimonabant, but not by the CB₂R or PPARα antagonists AM630 and MK886, respectively.

CONCLUSIONS:

These results indicate that URB597 reduces cue-induced reinstatement in rats through a CB₁ receptor-dependent mechanism, and not via CB₂R or PPARα. Since FAAH inhibition represent a novel and promising strategy for tobacco smoking cessation, dissecting how it produces its action may lead to a better understanding of the neurobiological mechanisms underlying nicotine addiction.”

http://www.ncbi.nlm.nih.gov/pubmed/26864774

A systematic review of plant-derived natural compounds for anxiety disorders.

Posted on February 5, 2016 by David

“Anxiety disorders are the most common mental illnesses affecting human beings. They range from panic to generalized anxiety disorders upsetting the well-being and psychosocial performance of patients. Several conventional anxiolytic drugs are being used which in turn result in several adverse effects. Therefore, studies to find suitable safe medicines from natural sources are being conducted by researchers.

The aim of the present study is to comprehensively review phytochemical compounds with well-established anxiolytic activities and their structure-activity relationships as well as neuropsychopharmacological aspects. Results showed that phytochemicals like; alkaloids, flavonoids, phenolic acids, lignans, cinnamates, terpenes and saponins possess anxiolytic effects in a wide range of animal models of anxiety.

The involved mechanisms include interaction with γ-aminobutyric acid (GABA)A receptors at benzodiazepine (BZD) and non-BZD sites with various affinity to different subunits, serotonergic 5-hydrodytryptamine (5-HT)1A and 5-HT2A/C receptors, noradrenergic and dopaminergic systems, glycine and glutamate receptors, and κ-opioid receptor as well as cannabinoid (CB)1 and CB2 receptors.

Phytochemicals also modulate the hypothalamo-pituitary-adrenal (HPA) axis, the levels of pro-inflammatory cytokines like interleukin (IL)-2, IL-6, IL-1β and tumor necrosis factor (TNF)-α, and improve brain derived neurotrophic factor (BDNF) levels. Transient receptor potential cation channel subfamily V (TRPV)3, nitric oxide cyclic guanosine monophosphate (NO-cGMP) pathway and monoamine oxidase enzymes are other targets of phytochemicals with anxiolytic activity.

Taking together, these phytochemicals may be considered as supplements to conventional anxiolytic therapies in order to improve efficacy and reduce adverse effects.

Further preclinical and clinical studies are still needed in order to recognize the structure-activity relationships, metabolism, absorption, and neuropsychopharmacological mechanisms of plant-derived natural agents.”

http://www.ncbi.nlm.nih.gov/pubmed/26845556

The Cannabinoid CB1/CB2 Agonist WIN55212.2 Promotes Oligodendrocyte Differentiation In Vitro and Neuroprotection During the Cuprizone-Induced Central Nervous System Demyelination.

Posted on February 5, 2016 by David

“Different types of insults to the CNS lead to axon demyelination. Remyelination occurs when the CNS attempts to recover from myelin loss and requires the activation of oligodendrocyte precursor cells.

With the rationale that CB1 receptor is expressed in oligodendrocytes and marijuana consumption alters CNS myelination, we study the effects of the cannabinoid agonist WIN55212.2 in (1) an in vitro model of oligodendrocyte differentiation and (2) the cuprizone model for demyelination.

The cannabinoid agonist WIN55212.2 promotes oligodendrocyte differentiation in vitro.

Moreover, 0.5 mg/kg of the drug confers neuroprotection during cuprizone-induced demyelination, while 1 mg/kg aggravates the demyelination process.”

http://www.ncbi.nlm.nih.gov/pubmed/26842941

Expression and Function of the Endocannabinoid System in the Retina and the Visual Brain.

Posted on February 4, 2016 by David

“Endocannabinoids are important retrograde modulators of synaptic transmission throughout the nervous system.

Cannabinoid receptors are seven transmembrane G-protein coupled receptors favoring Gi/o protein. They are known to play an important role in various processes, including metabolic regulation, craving, pain, anxiety, and immune function.

In the last decade, there has been a growing interest for endocannabinoids in the retina and their role in visual processing.

The purpose of this review is to characterize the expression and physiological functions of the endocannabinoid system in the visual system, from the retina to the primary visual cortex, with a main interest regarding the retina, which is the best-described area in this system so far.

It will show that the endocannabinoid system is widely present in the retina, mostly in the through pathway where it can modulate neurotransmitter release and ion channel activity, although some evidence also indicates possible mechanisms via amacrine, horizontal, and Müller cells.

The presence of multiple endocannabinoid ligands, synthesizing and catabolizing enzymes, and receptors highlights various pharmacological targets for novel therapeutic application to retinal diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26839718

Regulation of Stem Cells by the Endocannabinoid System

Posted on January 30, 2016 by David

“The endocannabinoids, endogenous lipid mediators of related chemical structure to the prototype exogenous cannabinoid Δ⁹-THC found in marijuana, have emerged as important mediators that regulate central and peripheral neural functions as well as immune responses.

Endogenous and exogenous cannabinoid ligands bind to cannabinoid receptors: the predominant central cannabinoid receptor type 1 (CB₁) and the peripheral cannabinoid receptor type 2 (CB₂). CB₁ and CB₂ are members of the G-protein coupled receptor family.

Cannabinoids were shown to modulate the immune system and to affect the migration of blood cells, such as T-cells, monocytes and myeloid leukemia cells, through CB receptors.

Recent data indicate the potential role of cannabinoid ligands and receptors in the regulation of hematopoiesis and hematopoietic stem cell (HSC) migration and trafficking.

These studies may lead to clinical applications of cannabinoid-based compounds as new HSC-mobilizer agents for therapeutic intervention in bone marrow failure.”

http://link.springer.com/chapter/10.1007/978-94-007-2993-3_30

Cannabinoid receptor signaling in progenitor/stem cell proliferation and differentiation.

Posted on January 30, 2016 by David

“Cannabinoids, the active components of cannabis (Cannabis sativa) extracts, have attracted the attention of human civilizations for centuries, much earlier than the discovery and characterization of their substrate of action, the endocannabinoid system (ECS).

The latter is an ensemble of endogenous lipids, their receptors [in particular type-1 (CB1) and type-2 (CB2) cannabinoid receptors] and metabolic enzymes.

Cannabinoid signaling regulates cell proliferation, differentiation and survival, with different outcomes depending on the molecular targets and cellular context involved.

Cannabinoid receptors are expressed and functional from the very early developmental stages, when they regulate embryonic and trophoblast stem cell survival and differentiation, and thus may affect the formation of manifold adult specialized tissues derived from the three different germ layers (ectoderm, mesoderm and endoderm).

In the ectoderm-derived nervous system, both CB1 and CB2 receptors are present in neural progenitor/stem cells and control their self-renewal, proliferation and differentiation. CB1 and CB2 show opposite patterns of expression, the former increasing and the latter decreasing along neuronal differentiation.

Recently, endocannabinoid (eCB) signaling has also been shown to regulate proliferation and differentiation of mesoderm-derived hematopoietic and mesenchymal stem cells, with a key role in determining the formation of several cell types in peripheral tissues, including blood cells, adipocytes, osteoblasts/osteoclasts and epithelial cells.

Here, we will review these new findings, which unveil the involvement of eCB signaling in the regulation of progenitor/stem cell fate in the nervous system and in the periphery.

The developmental regulation of cannabinoid receptor expression and cellular/subcellular localization, together with their role in progenitor/stem cell biology, may have important implications in human health and disease.”

http://www.ncbi.nlm.nih.gov/pubmed/24076098

CB2 cannabinoid receptors promote mouse neural stem cell proliferation.

Posted on January 30, 2016 by David

“Neurospheres are clonal cellular aggregates of neural stem/precursor cells that grow in culture as free-floating clusters. Activation of CB1 cannabinoid receptors, which are expressed by these cells, promotes proliferation.

In the present study we investigated the expression of CB2 cannabinoid receptors and the effect of exogenous cannabinoids on neural stem/precursor cell proliferation.

Neurospheres containing nestin-positive and sn-1 diacylglycerol lipase alpha-positive cells expressed both CB1 and CB2 receptors, which were maintained through several passages…

Together, our results suggest that cannabinoids stimulate proliferation of neural stem/precursor cells acting on both CB1 and CB2 cannabinoid receptors through a phosphoinositide-3 kinase/Akt pathway.”

http://www.ncbi.nlm.nih.gov/pubmed/17328768

Cannabinoid receptor 2 and its agonists mediate hematopoiesis and hematopoietic stem and progenitor cell mobilization.

Posted on January 30, 2016 by David

“Endocannabinoids are arachidonic acid derivatives and part of a novel bioactive lipid signaling system, along with their G-coupled cannabinoid receptors (CB₁ and CB₂) and the enzymes involved in their biosynthesis and degradation.

However, their roles in hematopoiesis and hematopoietic stem and progenitor cell (HSPC) functions are not well characterized. Here, we show that bone marrow stromal cells express endocannabinoids (anandamide and 2-arachidonylglycerol), whereas CB₂ receptors are expressed in human and murine HSPCs.

On ligand stimulation with CB₂ agonists, CB₂ receptors induced chemotaxis, migration, and enhanced colony formation of bone marrow cells, which were mediated via ERK, PI3-kinase, and Gαi-Rac1 pathways.

Taken together, these results demonstrate that the endocannabinoid system is involved in hematopoiesis and that CB₂/CB₂ agonist axis mediates repopulation of hematopoiesis and mobilization of HSPCs.

Thus, CB₂ agonists may be therapeutically applied in clinical conditions, such as bone marrow transplantation.”

http://www.ncbi.nlm.nih.gov/pubmed/21063029

Up-regulation of immunomodulatory effects of mouse bone-marrow derived mesenchymal stem cells by tetrahydrocannabinol pre-treatment involving cannabinoid receptor CB2.

Posted on January 30, 2016 by David

“Chronic pain is commonly and closely correlated with inflammation.

Both cannabinoid signaling and mesenchymal stem cells (MSCs) have been demonstrated to reduce inflammatory pain.

Although cannabinoid signaling is essential for mesenchymal stem cell survival and differentiation, little is known about its role in modulatory effect of MSCs on inflammation and pain sensitivity. Here we showed that mouse bone-marrow derived MSCs (BM-MSCs) expressed both cannabinoid receptor type 1 and 2 (CB1 and CB2). CB2 expression level in BM-MSCs increased with their maturation.

In addition, we found that tetrahydrocannabinol (THC) activated CB2 receptor and ERK signaling, consequently enhancing the modulation of MSCs on inflammation-associated cytokine release from lipopolysaccharides-stimulated microglia.

Consistent with in vitro data, THC pretreatment enhanced the immunomodulatory effects of BM-MSC on thermal hyperalgesia and mechanical allodynia in chronic constriction injury model, by decreasing the release of pro-inflammation cytokines.

Our study revealed the crucial role of THC in promoting the immunomodulatory effects of MSCs and proposed a new strategy to alleviate pain based on stem cells therapy.”

http://www.ncbi.nlm.nih.gov/pubmed/26824325