“Phytocannabinoids are produced in Cannabis sativa L. in acidic form and are decarboxylated upon heating, processing, and storage. While the biological effects of decarboxylated cannabinoids such as Δ9 -tetrahydrocannabinol (Δ9 -THC) have been extensively investigated, the bioactivity of Δ9 -THCA is largely unknown, despite its occurrence in different Cannabis preparations. The aim of this study was to determine whether Δ9 -THCA modulates the PPARγ pathway and has neuroprotective activity.
The effects of six phytocannabinoids on PPARγ binding and transcriptional activity were investigated. The effect of Δ9 -THCA on mitochondrial biogenesis and PGC-1α expression was investigated in N2a cells. The neuroprotective effect was analysed in STHdhQ111/Q111 cells expressing a mutated form of the huntingtin protein, and in N2a cells infected with an adenovirus carrying human huntingtin containing 94 polyQ repeats (mHtt-q94). In vivo neuroprotective activity of Δ9 -THCA was investigated in mice intoxicated with the mitochondrial toxin 3-nitropropionic acid (3-NP).
Cannabinoid acids bind and activate PPARγ with higher potency than their decarboxylated products. Δ9 -THCA increases mitochondrial mass in neuroblastoma N2a cells, and prevents cytotoxicity induced by serum deprivation in STHdhQ111/Q111cells and by mutHtt-q94 in N2a cells. Δ9 -THCA, through a PPARγ-dependent pathway, was neuroprotectant in mice intoxicated with 3-NP, improving motor deficits and preventing striatal degeneration. In addition, Δ9 -THCA attenuated microgliosis, astrogliosis and the upregulation of proinflammatory markers induced by 3-NP.
CONCLUSION AND IMPLICATIONS:
Δ9 -THCA shows potent neuroprotective activity, worth consideration for the treatment of Huntington´s Disease and possibly other neurodegenerative and neuroinflammatory diseases.”
“The endocannabinoid system consists of endogenous lipid mediators and cannabinoid receptors (CB) 1 and 2. It has previously been demonstrated that activation of the leukocyte-expressed CB2 has anti-inflammatory effects in vivo. Here, we report its role under baseline conditions and in a model of low-dose endotoxemia by comparing CB2 knockout to littermate control mice. CB2-deficient mice displayed significantly more neutrophils and fewer monocytes in the bone marrow under steady state. In initial validation experiments, administration of 1 mg/kg LPS to male C57BL/6J mice was shown to transiently upregulate systemic proinflammatory mediators (peaked at 2 hours) and mobilise bone marrow neutrophils and monocytes into circulation. In CB2 knockout mice, the level of the metalloproteinase MMP-9 was significantly elevated by 2 hours and we also observed augmented recruitment of neutrophils to the spleen in addition to increased levels of Ccl2, Ccl3, Cxcl10, and Il6. Collectively, our data show that the absence of CB2 receptor increases the levels of innate immune cell populations in the bone marrow under steady state. Furthermore, during an acute systemic inflammatory insult, we observe a highly reproducible and site-specific increase in neutrophil recruitment and proinflammatory chemokine expression in the spleen of CB2 knockout mice.” https://www.ncbi.nlm.nih.gov/pubmed/28852269
“In summary, we found that the lack of this GPCR leads to enhanced retention of neutrophils and increased release of monocytes in the bone marrow under steady state. We highlight a critical role for CB2 in regulating neutrophil infiltration to the spleen during acute systemic inflammation. A potential mechanism for this effect is the increased secretion of MMP-9 and Ccl3/Cxcl10 expression in the spleens of CB2 knockout mice. Taken together, we propose a novel role for CB2 in suppressing neutrophil migration to lymphoid organs under inflammatory conditions which we believe warrants further investigation.” https://www.hindawi.com/journals/mi/2017/4315412/
“Neurogenesis in the adult mammalian brain occurs mainly in two neurogenic niches, the subventricular zone (SVZ) and the subgranular zone (SGZ) of the dentate gyrus (DG). Cannabinoid type 1 and 2 receptors (CB1R and CB2R) have been shown to differently modulate neurogenesis. However, low attention has been given to the interaction between CB1R and CB2R in modulating postnatal neurogenesis (proliferation, neuronal differentiation and maturation).
We focused on a putative crosstalk between CB1R and CB2R to modulate neurogenesis and cultured SVZ and DG stem/progenitor cells from early postnatal (P1-3) Sprague-Dawley rats. Data showed that the non-selective cannabinoid receptor agonist WIN55,212-2 promotes DG cell proliferation (measured by BrdU staining), an effect blocked by either CB1R or CB2R selective antagonists. Experiments with selective agonists showed that facilitation of DG cell proliferation requires co-activation of both CB1R and CB2R. Cell proliferation in the SVZ was not affected by the non-selective receptor agonist, but it was enhanced by CB1R selective activation. However, either CB1R or CB2R selective antagonists abolished the effect of the CB1R agonist in SVZ cell proliferation. Neuronal differentiation (measured by immunocytochemistry against neuronal markers of different stages and calcium imaging) was facilitated by WIN55,212-2 at both SVZ and DG. This effect was mimicked by either CB1R or CB2R selective agonists and blocked by either CB1R or CB2R selective antagonists, cross-antagonism being evident.
In summary, our findings indicate a tight interaction between CB1R and CB2R to modulate neurogenesis in the two major neurogenic niches, thus contributing to further unraveling the mechanisms behind the action of endocannabinoids in the brain.”
“Cannabinoids, as multi‑target mediators, activate cannabinoid receptors and transient receptor potential vanilloid (TRPV) channels. There is evidence to support a functional interaction of cannabinoid receptors and TRPV channels when they are coexpressed.
Human conjunctiva demonstrates widespread cannabinoid receptor type 1 (CB1), CB2 and TRPV channel localization. The aim of the present study was to investigate the expression profile for cannabinoid receptors (CB1 and CB2) and TRPV channels in pterygium, an ocular surface lesion originating from the conjunctiva.
The differentiated expression of cannabinoid receptors in combination with the presence of TRPV channels, in primary and recurrent pterygia, imply a potential role of these cannabinoidtargets in the underlying mechanisms of pterygium.”
“Marijuana is a commonly used recreational substance with purported analgesic and mood enhancing properties. Many people living with HIV identify marijuana as a palliative substance.
However, through its main psychoactive component, tetrahydrocannabinol (THC), is known to influence the immune system. The effects of marijuana use in people with HIV are still controversial, with very scant literature in Black adults.
“These results extend previous HIV-related immunity findings in an underrepresented group, and suggest that THC use does not reduce immune function as measured by CD count. Further research is warranted on the overall effects of THC on immune function in HIV positive patients.” https://www.ncbi.nlm.nih.gov/pubmed/28850903
“Adverse effects of moderate Cannabis use on physical health are subtle and rarely fatal, while Cannabis use is associated with decreased rates of obesity, diabetes mellitus, mortality from traumatic brain injury, use of alcohol and prescription drugs, driving fatalities, and opioid overdose deaths.
These data suggest that Cannabis use may decrease premature deaths.
To date, no studies have attempted to estimate impacts of Cannabis use on premature death that include both adverse and beneficial effects on physical health. Marijuana use is estimated to reduce premature deaths from diabetes mellitus, cancer, and traumatic brain injury by 989 to 2,511 deaths for each 1% of the population using Cannabis. The analysis predicts an estimated 23,500 to 47,500 deaths prevented annually if medical marijuana were legal nationwide. A number of other potential causes of reduced mortality due to Cannabis use were revealed, but were excluded from the analysis because quantitative data were lacking. These estimates thus substantially underestimate the actual impact of Cannabis use on premature death.
Overall, prohibition is estimated to lead to similar numbers of premature deaths as drunk driving, homicide, or fatal opioid overdose. Cannabis use prevents thousands of premature deaths each year, and Cannabis prohibition is revealed as a major cause of premature death in the U.S.”
“Endocannabinoids are important regulators of neurotransmission and, acting on activated microglia, they are postulated as neuroprotective agents. Endocannabinoid action is mediated by CB1 and CB2 receptors, which may form heteromeric complexes (CB1-CB2Hets) with unknown function in microglia.
We aimed at establishing the expression and signaling properties of cannabinoidreceptors in resting and LPS/IFN-γ-activated microglia. Unlike CB1, CB2 receptors and CB1-CB2Hets were upregulated in activated microglia. Resting cell refractory CB2 receptors became robustly coupled to Gi in activated cells, in which CB1-CB2Hets mediated a positive cross-talk. Resting cells were refractory while activated cells were highly responsive to cannabinoids. Interestingly, similar results were obtained in cultures treated with ß-amyloid (Aß1-42). Activation microglial markers were detected in the striatum of a Parkinson’s disease (PD) model and, remarkably, in primary microglia cultures from the hippocampus of mutant β-amyloid precursor protein (APPSw,Ind) mice, a transgenic Alzheimer’s disease (AD) model. Also of note was the similar cannabinoid receptor signaling found in primary cultures of microglia from APPSw,Ind and in cells from control animals activated using LPS plus IFN- γ. Expression of CB1-CB2Hets was increased in the striatum from rats rendered dyskinetic by chronic levodopa treatment.
In summary, our results showed sensitivity of activated microglial cells to cannabinoids, increased CB1-CB2Het expression in activated microglia and in microglia from the hippocampus of an AD model, and a correlation between levodopa-induced dyskinesia and striatal microglial activation in a PD model. Cannabinoid receptors and the CB1-CB2 heteroreceptor complex in activated microglia have potential as targets in the treatment of neurodegenerative diseases.”
“Epilepsy is one of the world’s oldest recognized and prevalent neurological diseases. It has a great negative impact on patients’ quality of life (QOL) as a consequence of treatment resistant seizures in about 30% of patients together with drugs’ side effects and comorbidities. Therefore, new drugs are needed and cannabinoids, above all cannabidiol, have recently gathered attention.
This review summarizes the scientific data from human and animal studies on the major cannabinoids which have been of interest in the treatment of epilepsy, including drugs acting on the endocannabinoid system.
Despite the fact that cannabis has been used for many purposes over 4 millennia, the development of drugs based on cannabinoids has been very slow. Only recently, research has focused on their potential effects and CBD is the first treatment of this group with clinical evidence of efficacy in children with Dravet syndrome; moreover, other studies are currently ongoing to confirm its effectiveness in patients with epilepsy.
On the other hand, it will be of interest to understand whether drugs acting on the endocannabinoid system will be able to reach the market and prove their known preclinical efficacy also in patients with epilepsy.”
“The human cannabinoid subtype 1 receptor (hCB1R) is highly expressed in the CNS and serves as a therapeutic target for endogenous ligands as well as plant-derived and synthetic cannabinoids. Unfortunately, acute use of hCB1R agonists produces unwanted psychotropic effects and chronic administration results in development of tolerance and dependence, limiting the potential clinical use of these ligands. Studies in β-arrestin knockout mice suggest that interaction of certain GPCRs, including μ-, δ-, κ-opioid and hCB1Rs, with β-arrestins might be responsible for several adverse effects produced by agonists acting at these receptors. Indeed, agonists that bias opioid receptor activation toward G-protein, relative to β-arrestin signaling, produce less severe adverse effects. These observations indicate that therapeutic utility of agonists acting at hCB1Rs might be improved by development of G-protein biased hCB1R agonists. Our laboratory recently reported a novel class of indole quinulidinone (IQD) compounds that bind cannabinoid receptors with relatively high affinity and act with varying efficacy. The purpose of this study was to determine whether agonists in this novel cannabinoid class exhibit ligand bias at hCB1 receptors. Our studies found that a novel IQD-derived hCB1receptor agonist PNR-4-20 elicits robust G protein-dependent signaling, with transduction ratios similar to the non-biased hCB1R agonist CP-55,940. In marked contrast to CP-55,940, PNR-4-20 produces little to no β-arrestin 2 recruitment. Quantitative calculation of bias factors indicates that PNR-4-20 exhibits from 5.4-fold to 29.5-fold bias for G protein, relative to β-arrestin 2 signaling (when compared to G protein activation or inhibition of forskolin-stimulated cAMP accumulation, respectively). Importantly, as expected due to reduced β-arrestin 2 recruitment, chronic exposure of cells to PNR-4-20 results in significantly less desensitization and down-regulation of hCB1Rs compared to similar treatment with CP-55,940. PNR-4-20 (i.p.) is active in the cannabinoid tetrad in mice and chronic treatment results in development of less persistent tolerance and no significant withdrawal signs when compared to animals repeatedly exposed to the non-biased full agoinst JWH-018 or Δ9-THC. Finally, studies of a structurally similar analog PNR- 4-02 show that it is also a G protein biased hCB1R agonist. It is predicted that cannabinoid agonists that bias hCB1R activation toward G protein, relative to β-arrestin 2 signaling, will produce fewer and less severe adverse effects both acutely and chronically.”
“The endocannabinoid system encompassing cannabinoid receptors, endogenous receptor ligands (endocannabinoids), as well as enzymes conferring the synthesis and degradation of endocannabinoids has emerged as a considerable target for pharmacotherapeutical approaches of numerous diseases. Besides palliative effects of cannabinoids used in cancer treatment, phytocannabinoids, synthetic agonists, as well as substances that increase endogenous endocannabinoid levels have gained interest as potential agents for systemic cancer treatment. Accordingly, cannabinoid compounds have been reported to inhibit tumor growth and spreading in numerous rodent models. The underlying mechanisms include induction of apoptosis, autophagy, and cell cycle arrest in tumor cells as well as inhibition of tumor cell invasion and angiogenic features of endothelial cells. In addition, cannabinoids have been shown to suppress epithelial-to-mesenchymal transition, to enhance tumor immune surveillance, and to support chemotherapeutics’ effects on drug-resistant cancer cells. However, unwanted side effects include psychoactivity and possibly pathogenic effects on liver health. Other cannabinoids such as the nonpsychoactive cannabidiol exert a comparatively good safety profile while exhibiting considerable anticancer properties. So far experience with anticarcinogenic effects of cannabinoids is confined to in vitro studies and animal models. Although a bench-to-bedside conversion remains to be established, the current knowledge suggests cannabinoid compounds to serve as a group of drugs that may offer significant advantages for patients suffering from cancer diseases. The present review summarizes the role of the endocannabinoid system and cannabinoid compounds in tumor progression.”