“Liver fatty acid binding protein (FABP1, L-FABP) has high affinity for and enhances uptake of arachidonic acid (ARA, C20:4, n-6) which, when esterified to phospholipids, is the requisite precursor for synthesis of endocannabinoids (EC) such as arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG). The brain derives most of its ARA from plasma, taking up ARA and transporting it intracellularly via cytosolic fatty acid binding proteins (FABPs 3,5, and 7) localized within the brain. In contrast, the much more prevalent cytosolic FABP1 is not detectable in the brain but is instead highly expressed in the liver. Therefore, the possibility that FABP1 outside the central nervous system may regulate brain AEA and 2-AG was examined in wild-type (WT) and FABP1 null (LKO) male mice. LKO increased brain levels of AA-containing EC (AEA, 2-AG), correlating with increased free and total ARA in brain and serum. LKO also increased brain levels of non-ARA that contain potentiating endocannabinoids (EC*) such as OEA, PEA, 2-OG, and 2-PG. Concomitantly, LKO decreased serum total ARA-containing EC, but not non-ARA endocannabinoids. LKO did not elicit these changes in the brain EC and EC* due to compensatory upregulation of brain protein levels of enzymes in EC synthesis (NAPEPLD, DAGLα) or cytosolic EC chaperone proteins (FABPs 3, 5, 7, SCP-2, HSP70), or cannabinoid receptors (CB1, TRVP1). These data show for the first time that the non-CNS fatty acid binding protein FABP1 markedly affected brain levels of both ARA-containing endocannabinoids (AEA, 2-AG) as well as their non-ARA potentiating endocannabinoids.”
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FABP1 in wonderland.
“Cannabinoid receptors hold a core position in the brain and control memory, cognition, movement, and pain sensitivity. sn-2 arachidonoylglycerol (2-AG) activates neuronal cannabinoid receptors as a full agonist. The brain may rely on circulating arachidonic acid to synthesize endogenous cannabinoids. This Editorial highlights a study by Martin and coworkers in the current issue of the Journal of Neurochemistry in which the authors describe, for the first time, that liver acts as a pool of arachidonic acid that under certain conditions feeds the brain to produce endocannabinoids. Therapeutics affecting liver FABP1 levels should take into account that FABP1 represents a fatty acid reservoirs for the brain. Read the highlighted article “FABP-1 gene ablation impacts brain endocannabinoid system in male mice”” http://www.ncbi.nlm.nih.gov/pubmed/27329821
Activation of cannabinoid CB1 receptors suppresses the ROS-induced hypersensitivity of rat vagal lung C-fiber afferents.
“Reactive oxygen species (ROS), including H2O2, have been shown to induce hypersensitivity of vagal lung C-fibers (VLCFs) mainly through receptor potential ankyrin 1 (TRPA1) and P2X receptors.
Cannabinoids (CBs) exert antinociceptive effects by binding to specific CB receptors, designated CB1 and CB2 (type 2) for type 1 and type 2, respectively.
We investigated whether activation of CB receptors can suppress ROS-mediated VLCF hypersensitivity and, if so, what type(s) of CB receptors are involved.
:Our results suggest that activation of CB1 receptors may suppress the ROS-mediated VLCF hypersensitivity through a mechanism that is at least partly distinct from the function of TRPA1 and P2X receptors.”
Basolateral amygdala CB1 cannabinoid receptors are involved in cross state-dependent memory retrieval between morphine and ethanol.
“Ethanol and morphine are largely co-abused and affect memory formation.
The present study intended to investigate the involvement of cannabinoid CB1 receptors of the basolateral amygdala (BLA) in cross state-dependent memory retrieval between morphine and ethanol.
Taken together, it can be concluded that morphine and ethanol can induce state-dependent memory retrieval.
In addition, the BLA endocannabinoid system mediates via CB1 receptors the functional interaction of morphine and ethanol state-dependent memory retrieval which may depend on the rewarding effects of the drugs.”
Susceptibility of Naegleria fowleri to delta 9-tetrahydrocannabinol.
“Growth of the pathogenic amoeboflagellate Naegleria fowleri is inhibited by delta 9-tetrahydrocannabinol (delta 9-THC).
delta 9-THC is amoebostatic at 5 to 50 micrograms/ml. delta 9-THC prevents enflagellation and encystment, but does not impair amoeboid movement. Calf serum at 10 and 20% (vol/vol) reduces the antiamoeba activity of delta 9-THC.
Only 1-methoxy delta 8-tetrahydrocannabinol, of 17 cannabinoids tested, failed to inhibit growth of N. fowleri.
Antinaeglerial activity was not markedly altered by opening the pyran ring, by converting the cyclohexyl ring to an aromatic ring, or by reversing the hydroxyl and pentyl groups on the benzene ring.
delta 9-THC prevented the cytopathic effect of N. fowleri on African green monkey (Vero) cells and human epithelioma (HEp-2) cells in culture. delta 9-THC afforded modest protection to mice infected with N. fowleri.”
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC352928/
https://aac.asm.org/content/16/5/674?maxtoshow=&hits=80&RESULTFORMAT=&fulltext=ma
“Naegleria fowleri, colloquially known as the “brain-eating amoeba“” https://en.wikipedia.org/wiki/Naegleria_fowleri
Identification of Psychoactive Degradants of Cannabidiol in Simulated Gastric and Physiological Fluid
“The flowering plants of the genus Cannabis, which mainly comprises the sativa and indica species, have been recognized for medical treatment for millennia.
Although Cannabis contains nearly 500 compounds from 18 chemical classes, its physiological effects derive mainly from a family of naturally occurring compounds known as plant cannabinoids or phytocannabinoids. Of the more than 100 phytocannabinoids that have been identified in Cannabis, among the most important and widely studied are its main psychoactive constituent, Δ9-tetrahydrocannabinol (Δ9-THC), and the most important nonpsychoactive component, cannabidiol (CBD). Other biologically active phytocannabinoids that have been isolated in Cannabis include Δ8-THC, cannabinol, Δ9-tetrahydrocannabivarin, and cannabidivarin.
In recent research, orally administered cannabidiol (CBD) showed a relatively high incidence of somnolence in a pediatric population. Previous work has suggested that when CBD is exposed to an acidic environment, it degrades to Δ9-tetrahydrocannabinol (THC) and other psychoactive cannabinoids. To gain a better understanding of quantitative exposure, we completed an in vitro study by evaluating the formation of psychoactive cannabinoids when CBD is exposed to simulated gastric fluid (SGF).
SGF converts CBD into the psychoactive components Δ9-THC and Δ8-THC. The first-order kinetics observed in this study allowed estimated levels to be calculated and indicated that the acidic environment during normal gastrointestinal transit can expose orally CBD-treated patients to levels of THC and other psychoactive cannabinoids that may exceed the threshold for a physiological response. Delivery methods that decrease the potential for formation of psychoactive cannabinoids should be explored.
Despite persistent challenges with dosing and administration, CBD-based therapies have a good safety profile and a potential for efficacy in the treatment of a variety of medical conditions. The rapidly evolving sciences of drug delivery and cannabinoid pharmacology may soon lead to breakthroughs that will improve access to the benefits of this pharmacological class of agents. In addition, current technologies, such as transdermal-based therapy, may be able to eliminate the potential for psychotropic effects due to this acid-catalyzed cyclization by delivering CBD through the skin and into the neutral, nonreactive environment of the systemic circulation.”
Hypothermia induced by delta9-tetrahydrocannabinol in rats with electrolytic lesions of preoptic region.
“The preoptic region (POR) is a primary central site for thermoregulation. Bilateral lesions of POR disrupt thermoregulation, and in rats, produce a characteristic syndrome including hyperthermia.
delta9-Tetrahydrocannabinol (delta9-THC), a potent hypothermic agent, appears to mediate this effect via some central mechanism. The studies reported here suggest that delta9-THC induces hypothermia at a site other than POR.
These data demonstrate that delta9-THC is able to induce a hypothermic response in rats whose body temperatures were elevated by POR ablation. Although delta9-THC does not appear to act primarily at POR to induce hypothermia, it is evident than an intact POR plays a role in modifying the duration and magnitude of delta9-THC induced hypothermia.”
Cannabinoid receptor agonism suppresses tremor, cognition disturbances and anxiety-like behaviors in a rat model of essential tremor.
“Cognitive and motor disturbances are serious consequences of tremor induced by motor disorders. Despite a lack of effective clinical treatment, some potential therapeutic agents have been used to alleviate the cognitive symptoms in the animal models of tremor.
In the current study, the effects of WIN55, 212-2 (WIN), a cannabinoid receptor (CBR) agonist, on harmaline-induced motor and cognitive impairments was studied.
The neuroprotective and anxiolytic effects of WIN demonstrated in the current study can be offered cannabinoid receptor (CBR) agonism as a potential neuroprotective agent in the treatment of patients with tremor that manifest mental dysfunctions.”
Autophagy activation by novel inducers prevents BECN2-mediated drug tolerance to cannabinoids.
“Cannabinoids and related drugs generate profound behavioral effects (such as analgesic effects) through activating CNR1 (cannabinoid receptor 1 [brain]). However, repeated cannabinoid administration triggers lysosomal degradation of the receptor and rapid development of drug tolerance, limiting the medical use of marijuana in chronic diseases.
Here we show that a protein involved in macroautophagy/autophagy (a conserved lysosomal degradation pathway), BECN2 (beclin 2), mediates cannabinoid tolerance by preventing CNR1 recycling and resensitization after prolonged agonist exposure, and deletion of Becn2 rescues CNR1 activity in mouse brain and conveys resistance to analgesic tolerance to chronic cannabinoids.
Overall, our findings demonstrate the functional link among autophagy, receptor signaling and animal behavior regulated by psychoactive drugs, and develop a new strategy to prevent tolerance and improve medical efficacy of cannabinoids by modulating the BECN2 interactome and autophagy activity.”
Indirect modulation of the endocannabinoid system by specific fractions of nutmeg total extract.
“Nutmeg [Myristica fragrans Houtt. (Myristicaceae)] has a long-standing reputation of psychoactivity. Anecdotal reports of nutmeg use as a cheap marijuana substitute, coupled to previous studies reporting a cannabimimetic-like action, suggest that nutmeg may interact with the endocannabinoid system.
The study provides the first piece of evidence that nutmeg interacts with the endocannabinoid system via inhibition of the endocannabinoid catabolizing enzymes. This mechanism provides insight into reported cannabis-like action as well as expands the potential therapeutic utility of nutmeg.”
http://www.ncbi.nlm.nih.gov/pubmed/27296774