“Cannabinoids impact human body by binding to cannabinoids receptors (CB1 and CB2). The two main phytocannabinoids are Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC interacts with CB1 receptors occurring in central nervous system and is responsible for psychoactive properties of marijuana. CBD has low affinity to CB1 receptor, has no psychoactive characteristics and its medical applications can be wider. CB receptors are part of a complex machinery involved in regulation of many physiological processes – endocannabinoid system. Cannabinoids have found some applications in palliative medicine, but there are many reports concerning their anticancer affects. Agonists of CB1 receptors stimulate accumulation of ceramides in cancer cells, stress of endoplasmic reticulum (ER stress) and, in turn, apoptosis. Effects of cannabinoids showing low affinity to CB receptors is mediated probably by induction of reactive oxygen species production. Knowledge of antitumor activity of cannabinoids is still based only on preclinical studies and there is a necessity to conduct more experiments to assess the real potential of these compounds.” https://content.sciendo.com/view/journals/fobio/12/1/article-p11.xml]]>
Tag Archives: agonists
Repeated social defeat-induced neuroinflammation, anxiety-like behavior and resistance to fear extinction were attenuated by the cannabinoid receptor agonist WIN55,212-2.
“Psychosocial stress contributes to the development of psychiatric disorders. Repeated social defeat (RSD) is a murine stressor that causes a release of inflammatory monocytes into circulation. Moreover, RSD-induced anxiety-like behavior is dependent on the recruitment of these monocytes to the brain.
Activation of the endocannabinoid (ECB) system may modulate both neuroendocrine and inflammatory responses mediated by stress. Therefore, we hypothesized that a cannabinoid receptor agonist would attenuate RSD-induced inflammation, anxiety, and stress sensitization.
In conclusion, activation of cannabinoid receptors limited the immune and neuroinflammatory responses to RSD and reversed the short-term and long-term behavioral deficits associated with RSD.”
https://www.ncbi.nlm.nih.gov/pubmed/29786066
https://www.nature.com/articles/s41386-018-0064-2
Controlled-Deactivation CB1 Receptor Ligands as a Novel Strategy to Lower Intraocular Pressure.
“Nearly half a century has passed since the demonstration that cannabis and its chief psychoactive component Δ⁸-THC lowers intraocular pressure (IOP).
Elevated IOP remains the chief hallmark and therapeutic target for glaucoma, a condition that places millions at risk of blindness. It is likely that Δ⁸-THC exerts much of its IOP-lowering effects via the activation of CB1 cannabinoid receptors.
However, the initial promise of CB1 as a target for treating glaucoma has not thus far translated into a credible therapeutic strategy. We have recently shown that blocking monoacylglycerol lipase (MAGL), an enzyme that breaks the endocannabinoid 2-arachidonoyl glycerol (2-AG), substantially lowers IOP.
Another strategy is to develop cannabinoid CB1 receptor agonists that are optimized for topical application to the eye. Recently we have reported on a controlled-deactivation approach where the “soft” drug concept of enzymatic deactivation was combined with a “depot effect” that is commonly observed with Δ⁸-THC and other lipophilic cannabinoids.
This approach allowed us to develop novel cannabinoids with a predictable duration of action and is particularly attractive for the design of CB1 activators for ophthalmic use with limited or no psychoactive effects.
We have tested a novel class of compounds using a combination of electrophysiology in autaptic hippocampal neurons, a well-characterized model of endogenous cannabinoid signaling, and measurements of IOP in a mouse model.
We now report that AM7410 is a reasonably potent and efficacious agonist at CB1 in neurons and that it substantially (30%) lowers IOP for as long as 5 h after a single topical treatment. This effect is absent in CB1 knockout mice.
Our results indicate that the direct targeting of CB1 receptors with controlled-deactivation ligands is a viable approach to lower IOP in a murine model and merits further study in other model systems.”
https://www.ncbi.nlm.nih.gov/pubmed/29786643
http://www.mdpi.com/1424-8247/11/2/50
“Many malignant cancers, including breast cancer, have a propensity to invade bones, leading to excruciating bone pain.
Opioids are the primary analgesics used to alleviate this cancer-induced bone pain (CIBP) but are associated with numerous severe side effects, including enhanced bone degradation, which significantly impairs patients’ quality of life.
In contrast, agonists activating only peripheral CB1 receptors (CB1Rs) have been shown to effectively alleviate multiple chronic pain conditions with limited side effects, yet no studies have evaluated their role(s) in CIBP.
Here, we demonstrate for the first time that a peripherally selective CB1R agonist can effectively suppress CIBP.
Overall, our studies demonstrate that CIBP can be effectively managed by using a peripherally restricted CB1R agonist, PrNMI, without inducing dose-limiting central side effects.
Thus, targeting peripheral CB1Rs could be an alternative therapeutic strategy for the treatment of CIBP.”
“Anandamide is an endogenous ligand at both the inhibitory cannabinoid CB(1) receptor and the excitatory vanilloid receptor 1 (VR1). The CB(1) receptor and vanilloid VR1 receptor are expressed in about 50% and 40% of dorsal root ganglion neurons, respectively. While all vanilloid VR1 receptor-expressing cells belong to the calcitonin gene-related peptide-containing and isolectin B4-binding sub-populations of nociceptive primary sensory neurons, about 80% of the cannabinoid CB(1) receptor-expressing cells belong to those sub-populations. Furthermore, all vanilloid VR1 receptor-expressing cells co-express the cannabinoid CB(1) receptor.
In agreement with these findings, neonatal capsaicin treatment that induces degeneration of capsaicin-sensitive, vanilloid VR1 receptor-expressing, thin, unmyelinated, nociceptive primary afferent fibres significantly reduced the cannabinoid CB(1) receptor immunostaining in the superficial spinal dorsal horn.
Synthetic cannabinoid CB(1) receptor agonists, which do not have affinity at the vanilloid VR1 receptor, and low concentrations of anandamide both reduce the frequency of miniature excitatory postsynaptic currents and electrical stimulation-evoked or capsaicin-induced excitatory postsynaptic currents in substantia gelatinosa cells in the spinal cord without any effect on their amplitude. These effects are blocked by selective cannabinoid CB(1) receptor antagonists. Furthermore, the paired-pulse ratio is increased while the postsynaptic response of substantia gelatinosa neurons induced by alpha-amino-3-hydroxy-5-methylisoxasole-propionic acid (AMPA) in the presence of tetrodotoxin is unchanged following cannabinoid CB(1) receptor activation.
These results strongly suggest that the cannabinoid CB(1) receptor is expressed presynaptically and that the activation of these receptors by synthetic cannabinoid CB(1) receptor agonists or low concentration of anandamide results in inhibition of transmitter release from nociceptive primary sensory neurons. High concentrations of anandamide, on the other hand, increase the frequency of miniature excitatory postsynaptic currents recorded from substantia gelatinosa neurons. This increase is blocked by ruthenium red, suggesting that this effect is mediated through the vanilloid VR1 receptor.
Thus, anandamide at high concentrations can activate the VR1 and produce an opposite, excitatory effect to its inhibitory action produced at low concentrations through cannabinoid CB(1) receptor activation. This “dual”, concentration-dependent effect of anandamide could be an important presynaptic modulatory mechanism in the spinal nociceptive system.”
“2-Arachidonoylglycerol (2-AG) is a signaling lipid in the central nervous system that is a key regulator of neurotransmitter release. 2-AG is an 
“Alzheimer’s disease is a multifactorial disorder for which there is no disease-modifying treatment yet.
CB2 receptors have emerged as a promising therapeutic target for Alzheimer’s disease because they are expressed in neuronal and glial cells and their activation has no psychoactive effects.