Cannabinoid receptor-1 antagonism: a new perspective on treating a murine schistosomal liver fibrosis model.

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 SciELO - Scientific Electronic Library Online“Formation of schistosomal granulomata surrounding the ova can result in schistosomiasis-associated liver fibrosis (SSLF). The current standard of treatment is praziquantel (PZQ), which cannot effectively reverse SSLF.

The role of the cannabinoid (CB) receptor family in liver fibrosis has recently been highlighted.

This study aimed to assess the therapeutic effect of CB1 receptor antagonism in reversing SSLF in a murine model of Schistosoma mansoni infection.

MAIN CONCLUSIONS:

Combining PZQ with CB1 receptor antagonists yielded the best results in reversing SSLF. To our knowledge, this is the first study to test this regimen in S. mansoni infection.”

https://www.ncbi.nlm.nih.gov/pubmed/31389521

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762019000100338&tlng=en

Cannabinoid CB2 Receptor Modulation by the Transcription Factor NRF2 is Specific in Microglial Cells.

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 “Nuclear factor erythroid 2-related factor 2 (NRF2) is a pleiotropic transcription factor that has neuroprotective and anti-inflammatory effects, regulating more than 250 genes. As NRF2, cannabinoid receptor type 2 (CB2) is also implicated in the preservation of neurons against glia-driven inflammation. To this concern, little is known about the regulation pathways implicated in CB2 receptor expression. In this study, we analyze whether NRF2 could modulate the transcription of CB2 in neuronal and microglial cells. Bioinformatics analysis revealed an antioxidant response element in the promoter sequence of the CB2 receptor gene. Further analysis by chemical and genetic manipulations of this transcription factor demonstrated that NRF2 is not able to modulate the expression of CB2 in neurons. On the other hand, at the level of microglia, the expression of CB2 is NRF2-dependent. These results are related to the differential levels of expression of both genes regarding the brain cell type. Since modulation of CB2 receptor signaling may represent a promising therapeutic target with minimal psychotropic effects that can be used to modulate endocannabinoid-based therapeutic approaches and to reduce neurodegeneration, our findings will contribute to disclose the potential of CB2 as a novel target for treating different pathologies.”

https://www.ncbi.nlm.nih.gov/pubmed/31385133

https://link.springer.com/article/10.1007%2Fs10571-019-00719-y

Δ9-Tetrahydrocannabinol suppresses monocyte-mediated astrocyte production of MCP-1 and IL-6 in a TLR7-stimulated human co-culture.

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Journal of Pharmacology and Experimental Therapeutics“Cannabis is widely used in the United States with an estimated prevalence of 9.5%. Certain cannabinoids in Cannabis sativa, in particular, Δ9-tetrahydrocannabinol (THC), possess immune modulating and anti-inflammatory activity. Depending on the context, the anti-inflammatory activity of cannabinoids may be beneficial, such as in treating inflammatory diseases, or detrimental to normal immune defense against pathogens. The potential beneficial impact of cannabinoids on chronic neuroinflammation has gained recent attention. Monocyte migration to the brain has been implicated as a key event in chronic neuroinflammation and in the etiology of central nervous system diseases including viral infection (e.g., HIV-associated neurocognitive disorder). In the brain, monocytes can contribute to neuroinflammation through interactions with astrocytes, including inducing astrocyte secretion of cytokines and chemokines. In a human co-culture system, monocyte-derived IL-1β due to toll-like receptor 7 (TLR7)-activation, has been identified to promote astrocyte production of MCP-1 and IL-6. THC treatment of TLR7-stimulated co-culture suppressed monocyte secretion of IL-1β resulting in decreased astrocyte production of MCP-1 and IL-6. Furthermore, THC displayed direct inhibition of monocytes, as TLR7-stimulated monocyte monocultures treated with THC also showed suppressed IL-1β production. The cannabinoid receptor 2 (CB2) agonist, JWH-015, impaired monocyte IL-1β production similar to that of THC, suggesting THC is, in part, acting through CB2. THC also suppressed key elements of the IL-1β production pathway, including IL1B mRNA levels and caspase-1 activity. Collectively, this study demonstrates that the anti-inflammatory properties of THC suppress TLR7-induced monocyte secretion of IL-1β, through CB2, which results in decreased astrocyte secretion of MCP-1 and IL-6.

SIGNIFICANCE STATEMENT: As cannabis use is highly prevalent in the United States and has putative anti-inflammatory properties, it is important to investigate the effect of cannabinoids on immune cell function. Furthermore, cannabinoids have garnered particular interest due to their potential beneficial effects on attenuating viral-induced chronic neuroinflammation. This study utilized a primary human co-culture system to demonstrate that the major psychotropic cannabinoid in cannabis, Δ9-tetrahydrocannabinol (THC) and a cannabinoid receptor-2 (CB2) selective agonist, suppress specific monocyte-mediated astrocyte inflammatory responses. In the context of viral-induced chronic neuroinflammation, the findings presented here suggest that cannabinoids via CB2 ligation may have beneficial anti-inflammatory effects.”

https://www.ncbi.nlm.nih.gov/pubmed/31383729

http://jpet.aspetjournals.org/content/early/2019/08/05/jpet.119.260661

Cannabis and Epilepsy.

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 Publication Cover“In recent years, the use of cannabidiol in the treatment of refractory epilepsy has been increasingly investigated and has been gaining public support as a novel way to treat these disorders.

Marijuana has been used for medical purposes for thousands of years, and a lot of research has been conducted over the last several decades into the chemistry and pharmacology of marijuana and its many compounds, including cannabidiol.

There are historical and recent scientific developments that support the use of cannabidiol in rare severe epilepsy syndromes.”

https://www.ncbi.nlm.nih.gov/pubmed/31385740

https://www.tandfonline.com/doi/abs/10.1080/15504263.2019.1645372?journalCode=wjdd20

Cannabidiol Regulates the Expression of Keratinocyte Proteins Involved in the Inflammation Process through Transcriptional Regulation.

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cells-logo “Cannabidiol (CBD), a natural phytocannabinoid without psychoactive effect, is a well-known anti-inflammatory and antioxidant compound.

The possibility of its use in cytoprotection of cells from harmful factors, including ultraviolet (UV) radiation, is an area of ongoing investigation. Therefore, the aim of this study was to evaluate the effect of CBD on the regulatory mechanisms associated with the redox balance and inflammation in keratinocytes irradiated with UVA [30 J/cm2] and UVB [60 mJ/cm2].

Spectrophotometric results show that CBD significantly enhances the activity of antioxidant enzymes such as superoxide dismutase and thioredoxin reductase in UV irradiated keratinocytes. Furthermore, despite decreased glutathione peroxidase and reductase activities, CBD prevents lipid peroxidation, which was observed as a decreased level of 4-HNE and 15d-PGJ2 (measured using GC/MS and LC/MS). Moreover, Western blot analysis of protein levels shows that, under stress conditions, CBD influences interactions of transcription factors Nrf2- NFκB by inhibiting the NFκB pathway, increasing the expression of Nrf2 activators and stimulating the transcription activity of Nrf2.

In conclusion, the antioxidant activity of CBD through Nrf2 activation as well as its anti-inflammatory properties as an inhibitor of NFκB should be considered during design of new protective treatments for the skin.”

https://www.ncbi.nlm.nih.gov/pubmed/31382646

https://www.mdpi.com/2073-4409/8/8/827

THE EFFECTS OF MEDICAL MARIJUANA DISPENSARIES ON ADVERSE OPIOID OUTCOMES

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 Publication cover image“As more states enact laws liberalizing marijuana use and the U.S. opioid epidemic surges to unprecedented levels, understanding the relationship between marijuana and opioids is growing increasingly important.

Using a unique self‐constructed marijuana dispensary dataset, I estimate the impact of increased marijuana access on opioid‐related harms.

I exploit within‐ and across‐state variation in dispensary openings and find county‐level prescription opioid‐related fatalities decline by 11% following the opening a dispensary.

The estimated dispensary effects are qualitatively similar for opioid‐related admissions to treatment facilities. These results are strongest for males and suggest a substitutability between marijuana and opioids.”

https://onlinelibrary.wiley.com/doi/full/10.1111/ecin.12825

“I find that core-based statistical areas (CBSAs) with dispensary openings experience a 20 percentage point relative decrease in painkiller treatment admissions over the first two years of dispensary operations.”

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3012381

“Access to medical marijuana reduces opioid prescriptions”  https://www.health.harvard.edu/blog/access-to-medical-marijuana-reduces-opioid-prescriptions-2018050914509

THE EFFECTS OF RECREATIONAL MARIJUANA LEGALIZATION AND DISPENSING ON OPIOID MORTALITY

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Publication cover image“This study documents how the changing legal status of marijuana has impacted mortality in the United States over the past two decades.

We use a difference‐in‐difference approach to estimate the effect of medical marijuana laws (MML) and recreational marijuana laws (RML) on fatalities from opioid overdoses, and we find that marijuana access induces sharp reductions in opioid mortality rates.

Our research corroborates prior findings on MMLs and offers the first causal estimates of RML impacts on opioid mortality to date, the latter of which is particularly important given that RMLs are far more expansive in scope and reach than MMLs.

In our preferred econometric specification, we estimate that RMLs reduce annual opioid mortality in the range of 20%–35%, with particularly pronounced effects for synthetic opioids. In further analysis, we demonstrate how RML impacts vary among demographic groups, shedding light on the distributional consequences of these laws.

Our findings are especially important and timely given the scale of the opioid crisis in the United States and simultaneously evolving attitudes and regulations on marijuana use.”

https://onlinelibrary.wiley.com/doi/full/10.1111/ecin.12819

“Marijuana legalization reduces opioid deaths. A new Economic Inquiry study finds that marijuana access leads to reductions in opioid-related deaths.” https://medicalxpress.com/news/2019-08-marijuana-legalization-opioid-deaths.html

Endocannabinoid System and Alcohol Abuse Disorders.

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“Δ9-tetrahydrocannabinol (Δ9-THC), the primary active component in Cannabis sativa preparations such as hashish and marijuana, signals by binding to cell surface receptors. Two types of receptors have been cloned and characterized as cannabinoid (CB) receptors. CB1 receptors (CB1R) are ubiquitously present in the central nervous system (CNS) and are present in both inhibitory interneurons and excitatory neurons at the presynaptic terminal. CB2 receptors (CB2R) are demonstrated in microglial cells, astrocytes, and several neuron subpopulations and are present in both pre- and postsynaptic terminals.

The majority of studies on these receptors have been conducted in the past two and half decades after the identification of the molecular constituents of the endocannabinoid (eCB) system that started with the characterization of CB1R. Subsequently, the seminal discovery was made, which suggested that alcohol (ethanol) alters the eCB system, thus establishing the contribution of the eCB system in the motivation to consume ethanol. Several preclinical studies have provided evidence that CB1R significantly contributes to the motivational and reinforcing properties of ethanol and that the chronic consumption of ethanol alters eCB transmitters and CB1R expression in the brain nuclei associated with addiction pathways.

Additionally, recent seminal studies have further established the role of the eCB system in the development of ethanol-induced developmental disorders, such as fetal alcohol spectrum disorders (FASD). These results are augmented by in vitro and ex vivo studies, showing that acute and chronic treatment with ethanol produces physiologically relevant alterations in the function of the eCB system during development and in the adult stage. This chapter provides a current and comprehensive review of the literature concerning the role of the eCB system in alcohol abuse disorders (AUD).”

https://www.ncbi.nlm.nih.gov/pubmed/31332736

https://link.springer.com/chapter/10.1007%2F978-3-030-21737-2_6

“Binge Alcohol Exposure Transiently Changes the Endocannabinoid System: A Potential Target to Prevent Alcohol-Induced Neurodegeneration.”  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742761/

Endogenous cannabinoid levels and suicidality in combat veterans.

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Psychiatry Research“Combat veterans are at elevated suicide risk. The goal of this study was to test the hypothesis that combat veterans who have made a suicide attempt post-deployment can be distinguished from combat veterans who have never made a suicide attempt based on differences in psychological and biological variables. For the latter, we focused on endogenous cannabinoids, neuroendocrine markers that are associated with stress. Demographic and clinical parameters of suicide attempters and non-attempters were assessed. Blood samples were assayed for anandamide (AEA), 2-arachidonoylglycerol (2-AG), and cortisol. Suicide attempters had higher Scale for Suicidal Ideation (SSI) scores in comparison to non-attempters. Controlling for gender, 2-AG levels were higher among suicide attempters in comparison to non-attempters. Cortisol levels positively correlated with 2-AG levels and negatively correlated with SSI scores among non-attempters but not among attempters. AEA levels negatively correlated with SSI scores among attempters but not among non-attempters. Our results indicate that there are psychological and biological differences between combat veterans with or without a history of suicidal attempt. Our findings also suggest that clinically observed differences between the groups may have a neurobiological basis.”

https://www.ncbi.nlm.nih.gov/pubmed/31375282

https://www.sciencedirect.com/science/article/abs/pii/S0165178119315173?via%3Dihub

“Role of the Endocannabinoid System in the Neurobiology of Suicide”  https://www.ncbi.nlm.nih.gov/books/NBK107200/

Stable Adult Hippocampal Neurogenesis in Cannabinoid Receptor CB2 Deficient Mice.

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ijms-logo “The G-protein coupled cannabinoid receptor 2 (CB2) has been implicated in the regulation of adult neurogenesis in the hippocampus. The contribution of CB2 towards basal levels of proliferation and the number of neural progenitors in the subgranular zone (SGZ) of the dentate gyrus, however, remain unclear. We stained hippocampal brain sections of 16- to 17-week-old wildtype and CB2-deficient mice, for neural progenitor and immature neuron markers doublecortin (DCX) and calretinin (CR) and for the proliferation marker Ki67 and quantified the number of positive cells in the SGZ. The quantification revealed that CB2 deficiency neither altered overall cell proliferation nor the size of the DCX+ or DCX and CR double-positive populations in the SGZ compared to control animals. The results indicate that CB2 might not contribute to basal levels of adult neurogenesis in four-month-old healthy mice. CB2 signaling might be more relevant in conditions where adult neurogenesis is dynamically regulated, such as neuroinflammation.”

https://www.ncbi.nlm.nih.gov/pubmed/31374821

“Cannabinoids have been linked to the regulation of adult neurogenesis (AN), a process in the mammalian brain that takes place in stem cell niches in the adult brain and is responsible for the continued generation of new neurons.”

https://www.mdpi.com/1422-0067/20/15/3759/htm