The role of cannabinoids and leptin in neurological diseases.

Posted on April 17, 2015 by David

“Cannabinoids exert a neuroprotective influence on some neurological diseases, including Alzheimer’s, Parkinson’s, Huntington’s, multiple sclerosis and epilepsy.

Synthetic cannabinoid receptor agonists/antagonists or compounds can provide symptom relief or control the progression of neurological diseases. However, the molecular mechanism and the effectiveness of these agents in controlling the progression of most of these diseases remain unclear.

Cannabinoids may exert effects via a number of mechanisms and interactions with neurotransmitters, neurotropic factors and neuropeptides.

Leptin is a peptide hormone involved in the regulation of food intake and energy balance via its actions on specific hypothalamic nuclei. Leptin receptors are widely expressed throughout the brain, especially in the hippocampus, basal ganglia, cortex and cerebellum. Leptin has also shown neuroprotective properties in a number of neurological disorders, such as Parkinson’s and Alzheimer’s.

Therefore, cannabinoid and leptin hold therapeutic potential for neurological diseases.

Further elucidation of the molecular mechanisms underlying the effects on these agents may lead to the development of new therapeutic strategies for the treatment of neurological disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/25880465

Cannabidiol, a non-psychoactive cannabinoid, leads to EGR2-dependent anergy in activated encephalitogenic T cells.

Posted on April 17, 2015 by David

“Cannabidiol (CBD), the main non-psychoactive cannabinoid, has been previously shown by us to ameliorate clinical symptoms and to decrease inflammation in myelin oligodendrocyte glycoprotein (MOG)35-55-induced mouse experimental autoimmune encephalomyelitis model of multiple sclerosis as well as to decrease MOG35-55-induced T cell proliferation and IL-17 secretion. However, the mechanisms of CBD anti-inflammatory activities are unclear.

We found that CBD leads to upregulation of CD69 and lymphocyte-activation gene 3 (LAG3) regulatory molecules on CD4+CD25-accessory T cells. This subtype of CD4+CD25-CD69+LAG3+ T cells has been recognized as induced regulatory phenotype promoting anergy in activated T cells.

Indeed, we observed that CBD treatment results in upregulation of EGR2 (a key T cell anergy inducer) mRNA transcription in stimulated TMOG cells. This was accompanied by elevated levels of anergy promoting genes such as IL-10 (anti-inflammatory cytokine), STAT5 (regulatory factor), and LAG3 mRNAs, as well as of several enhancers of cell cycle arrest (such as Nfatc1, Casp4, Cdkn1a, and Icos).

Moreover, CBD exposure leads to a decrease in STAT3 and to an increase in STAT5 phosphorylation in TMOG cells, positive and negative regulators of Th17 activity, respectively. In parallel, we observed decreased levels of major histocompatibility complex class II (MHCII), CD25, and CD69 on CD19+ B cells following CBD treatment, showing diminished antigen presenting capabilities of B cells and reduction in their pro-inflammatory functions.

CONCLUSIONS:

Our data suggests that CBD exerts its immunoregulatory effects via induction of CD4+CD25-CD69+LAG3+ cells in MOG35-55-activated APC/TMOG co-cultures. This is accompanied by EGR2-dependent anergy of stimulated TMOG cells as well as a switch in their intracellular STAT3/STAT5 activation balance leading to the previously observed decrease in Th17 activity.”

http://www.ncbi.nlm.nih.gov/pubmed/25880134

Full-text: http://www.jneuroinflammation.com/content/12/1/52

Regulation of inflammation by cannabinoids, the endocannabinoids 2-arachidonoyl-glycerol and arachidonoyl-ethanolamide, and their metabolites.

Posted on April 17, 2015 by David

“2-Arachidonoyl-glycerol (2-AG) and arachidonyl-ethanolamide (AEA) are endocannabinoids that have been implicated in many physiologic disorders, including obesity, metabolic syndromes, hepatic diseases, pain, neurologic disorders, and inflammation.

Their immunomodulatory effects are numerous and are not always mediated by cannabinoid receptors, reflecting the presence of an arachidonic acid (AA) molecule in their structure, the latter being the precursor of numerous bioactive lipids that are pro- or anti-inflammatory.

2-AG and AEA can thus serve as a source of AA but can also be metabolized by most eicosanoid biosynthetic enzymes, yielding additional lipids.

In this regard, enhancing endocannabinoid levels by using endocannabinoid hydrolysis inhibitors is likely to augment the levels of these lipids that could regulate inflammatory cell functions.

This review summarizes the metabolic pathways involved in the biosynthesis and metabolism of AEA and 2-AG, as well as the biologic effects of the 2-AG and AEA lipidomes in the regulation of inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/25877930

Effects of Cannabinoids on T-cell Function and Resistance to Infection.

Posted on April 17, 2015 by David

“This review examines the effects of cannabinoids on immune function, with a focus on effects on T-cells, as well as on resistance to infection. The paper considers the immune modulating capacity of marijuana, of ∆9-THC extracted from the marijuana plant, and synthetic cannabinoids…

The overall conclusion of the studies discussed in this review is that cannabinoids that bind to the CB2 receptor, including ∆9-THC and CB2 selective agonists are immunosuppressive.

The studies provide objective evidence for potentially beneficial effects of marijuana and ∆9-THC on the immune system in conditions where it is desirable to dampen immune responses.

An emerging area of investigation that is reviewed is evidence to support the conclusion that CB2 selective agonists are a new class of immunosuppressive and anti-inflammatory compounds that may have exceptional beneficial effects in a variety of conditions, such as autoimmune diseases and graft rejection, where it is desirable to dampen the immune response without psychoactive effects.”

http://www.ncbi.nlm.nih.gov/pubmed/25876735

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

The dopamine theory of addiction: 40 years of highs and lows.

Posted on April 16, 2015 by David

“For several decades, addiction has come to be viewed as a disorder of the dopamine neurotransmitter system; however, this view has not led to new treatments. In this Opinion article, we review the origins of the dopamine theory of addiction and discuss the ability of addictive drugs to elicit the release of dopamine in the human striatum.

There is robust evidence that stimulants increase striatal dopamine levels and some evidence that alcohol may have such an effect, but little evidence, if any, that cannabis and opiates increase dopamine levels.

Moreover, there is good evidence that striatal dopamine receptor availability and dopamine release are diminished in individuals with stimulant or alcohol dependence but not in individuals with opiate, nicotine or cannabis dependence. These observations have implications for understanding reward and treatment responses in various addictions.”

http://www.ncbi.nlm.nih.gov/pubmed/25873042

http://www.thctotalhealthcare.com/category/addiction/

Endocannabinoids mediate bidirectional striatal spike-timing dependent plasticity.

Posted on April 16, 2015 by David

“Synaptic plasticity, a main substrate for learning and memory, is commonly assessed with prolonged stimulations. Since learning can arise from few or even a single trial, synaptic strength is expected to adapt rapidly. However, it remains elusive whether synaptic plasticity occurs in response to limited event occurrences. To answer this question, we investigated if a low number of paired stimulations can induce plasticity in a major synaptic learning rule, the spike-timing dependent plasticity (STDP). It is known that 100 pairings induce bidirectional STDP, i.e. spike-timing-dependent potentiation (tLTP) and depression (tLTD) at most central synapses. In rodent striatum, we found that tLTD progressively disappears when the number of paired stimulations is decreased (below 50 pairings) whereas tLTP displays a biphasic profile: tLTP is observed for 75-100 pairings, absent for 25-50 pairings and reemerges for 5-10 pairings. This tLTP, induced by very few pairings (∼5-10), depends on the endocannabinoid (eCB) system. This eCB-tLTP involves postsynaptic endocannabinoid synthesis, requires paired activity (post- and presynaptic) and the activation of type-1 cannabinoidreceptor (CB1R) and transient receptor potential vanilloid type-1 (TRPV1) activation. eCB-tLTP occurs in both striatopallidal and striatonigral MSNs and is dopamine-dependent. Lastly, we show that eCB-LTP and eCB-LTD can be induced sequentially in the same neuron, depending on the cellular conditioning paradigm. Thus, while usually considered as simply depressing synaptic function, endocannabinoids constitute a versatile system underlying bidirectional plasticity. Our results reveal a novel form of synaptic plasticity, eCB-tLTP, which may underlie rapid learning capabilities characterizing behavioral flexibility.”

http://www.ncbi.nlm.nih.gov/pubmed/25873197

WIN 55,212-2, Agonist of Cannabinoid Receptors, Prevents Amyloid β1-42 Effects on Astrocytes in Primary Culture.

Posted on April 16, 2015 by David

“Alzheimer´s disease (AD), a neurodegenerative illness involving synaptic dysfunction with extracellular accumulation of Aβ1-42 toxic peptide, glial activation, inflammatory response and oxidative stress, can lead to neuronal death.

Endogenous cannabinoid system is implicated in physiological and physiopathological events in central nervous system (CNS), and changes in this system are related to many human diseases, including AD…

In conclusion cannabinoid WIN 55,212-2 increases cell viability and anti-inflammatory response in cultured astrocytes. Moreover, WIN 55,212-2 increases expression of anti-oxidant Cu/Zn SOD and is able to prevent inflammation induced by Aβ1-42 in cultured astrocytes.

Further studies would be needed to assess the possible beneficial effects of cannabinoids in Alzheimer’s disease patients.”

http://www.ncbi.nlm.nih.gov/pubmed/25874692

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

Cannabis and cardiotoxicity.

Posted on April 16, 2015 by David

“Cannabis is the most commonly consumed illicit drug… Despite the drug’s extreme popularity, reports of cannabis-related stroke and myocardial infarction are so rare as to still be reportable… The observation that cardiotoxicity has never been reported in cancer patients taking dronabinol, the synthetic form of THC, tends to suggest that animal studies may have overstated the cardiovascular risk,” http://www.ncbi.nlm.nih.gov/pubmed/25868498

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

A role for GPR55 in human placental venous endothelial cells.

Posted on April 15, 2015 by David

“Endocannabinoids and their G protein-coupled receptors have been suggested to play a key role in human pregnancy, by regulating important aspects such as implantation, decidualization, placentation and labor.

G protein-coupled receptor 55 (GPR55) was previously postulated to be another cannabinoid receptor, since specific cannabinoids were shown to act independently of the classical cannabinoid receptors CB1 or CB2.

Current knowledge about GPR55 expression and function in human placenta is very limited and motivated us to evaluate human placental GPR55 expression in relation to other human peripheral tissues and to analyze spatiotemporal GPR55 expression in human placenta.

Gene expression analysis revealed low GPR55 levels in human placenta, when compared to spleen and lung, the organs showing highest GPR55 expression.

Moreover, expression analysis showed 5.8 fold increased placental GPR55 expression at term compared to first trimester. Immunohistochemistry located GPR55 solely at the fetal endothelium of first trimester and term placentas. qPCR and immunocytochemistry consistently confirmed GPR55 expression in isolated primary placental arterial and venous endothelial cells. Incubation with L-α-lysophosphatidylinositol (LPI), the specific and functional ligand for GPR55, at a concentration of 1 µM, significantly enhanced migration of venous, but not arterial endothelial cells.

LPI-enhanced migration was inhibited by the GPR55 antagonist O-1918, suggesting a role of the LPI-GPR55 axis in placental venous endothelium function.”

http://www.ncbi.nlm.nih.gov/pubmed/25869640

Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context.

Posted on April 15, 2015 by David

“Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis.

The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study…

Main results indicated that FAAH inhibitor URB597 decreased neural proliferation, glia and apoptosis in a brain region-dependent manner, which were coupled to local changes in Faah and/or Cnr1 expression and a negative energy context.”

http://www.ncbi.nlm.nih.gov/pubmed/25870539