“Cannabinoids are emerging as promising antitumor drugs. However, complete tumor eradication solely by cannabinoid therapy remains challenging. In this study, we developed a far-red light activatable cannabinoid prodrug, which allows for tumor-specific and combinatory cannabinoid and photodynamic therapy. This prodrug consists of a phthalocyanine photosensitizer (PS), reactive oxygen species (ROS)-sensitive linker, and cannabinoid. It targets the type-2 cannabinoid receptor (CB2R) overexpressed in various types of cancers. Upon the 690-nm light irradiation, the PS produces cytotoxic ROS, which simultaneously cleaves the ROS-sensitive linker and subsequently releases the cannabinoid drug. We found that this unique multifunctional prodrug design offered dramatically improved therapeutic efficacy, and therefore provided a new strategy for targeted, controlled, and effective antitumor cannabinoid therapy.”
Tag Archives: cannabinoid receptors
Anandamide Effects in a Streptozotocin-Induced Alzheimer’s Disease-Like Sporadic Dementia in Rats.
“Alzheimer’s disease (AD) is characterized by multiple cognitive deficits including memory and sensorimotor gating impairments as a result of neuronal and synaptic loss.
The endocannabinoid system plays an important role in these deficits but little is known about its influence on the molecular mechanism regarding phosphorylated tau (p-tau) protein accumulation – one of the hallmarks of AD -, and on the density of synaptic proteins.
Thus, the aim of this study was to investigate the preventive effects of anandamide (N-arachidonoylethanolamine, AEA) on multiple cognitive deficits and on the levels of synaptic proteins (syntaxin 1, synaptophysin and synaptosomal-associated protein, SNAP-25), cannabinoid receptor type 1 (CB1) and molecules related to p-tau degradation machinery (heat shock protein 70, HSP70), and Bcl2-associated athanogene (BAG2) in an AD-like sporadic dementia model in rats using intracerebroventricular (icv) injection of streptozotocin (STZ).
This study showed, for the first time, that the administration of an endocannabinoid can prevent AD-like effects induced by STZ, boosting further investigations about the modulation of endocannabinoid levels as a therapeutic approach for AD.”
Translational potential of allosteric modulators targeting the cannabinoid CB1 receptor.
“The cannabinoid type-1 (CB1) receptor, a G-protein-coupled receptor, is an attractive target for drug discovery due to its involvement in many physiological processes. Historically, drug discovery efforts targeting the CB1 receptor have focused on the development of orthosteric ligands that interact with the active site to which endogenous cannabinoids bind. Research performed over the last several decades has revealed substantial difficulties in translating CB1 orthosteric ligands into druggable candidates. The difficulty is mainly due to the adverse effects associated with orthosteric CB1 ligands. Recent discoveries of allosteric CB1 modulators provide tremendous opportunities to develop CB1 ligands with novel mechanisms of action; these ligands may potentially improve the pharmacological effects and enhance drug safety in treating the disorders by regulating the functions of the CB1 receptor. In this paper, we review and summarize the complex pharmacological profiles of each class of CB1 allosteric modulators, the development of new classes of CB1 allosteric modulators and the results from in vivo assessments of their therapeutic value.”
Structure-Based Identification of Potent Natural Product Chemotypes as Cannabinoid Receptor 1 Inverse Agonists.
“Natural products are an abundant source of potential drugs, and their diversity makes them a rich and viable prospective source of bioactive cannabinoid ligands.
Cannabinoid receptor 1 (CB1) antagonists are clinically established and well documented as potential therapeutics for treating obesity, obesity-related cardiometabolic disorders, pain, and drug/substance abuse, but their associated CNS-mediated adverse effects hinder the development of potential new drugs and no such drug is currently on the market. This limitation amplifies the need for new agents with reduced or no CNS-mediated side effects.
We are interested in the discovery of new natural product chemotypes as CB1 antagonists, which may serve as good starting points for further optimization towards the development of CB1 therapeutics.
Most importantly, these bioactive compounds represent structurally new natural product chemotypes in the area of cannabinoid research and could be considered for further structural optimization as CB1 ligands.”
Atypical Pharmacodynamic Properties and Metabolic Profile of the Abused Synthetic Cannabinoid AB-PINACA: Potential Contribution to Pronounced Adverse Effects Relative to Δ9-THC
“Recreational use of marijuana is associated with few adverse effects, but abuse of synthetic cannabinoids (SCBs) can result in anxiety, psychosis, chest pain, seizures and death.
To potentially explain higher toxicity associated with SCB use, we hypothesized that AB-PINACA, a common second generation SCB, exhibits atypical pharmacodynamic properties at CB1 cannabinoid receptors (CB1Rs) and/or a distinct metabolic profile when compared to Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive cannabinoid present in marijuana.
Taken collectively, the atypical pharmacodynamic properties of AB-PINACA at CB1Rs relative to Δ9-THC (e.g., higher potency/efficacy and greater production of desensitization), coupled with an unusual metabolic profile (e.g., production of metabolically stable active phase I metabolites) may contribute to the pronounced adverse effects observed with abuse of this SCB compared to marijuana.
““K2” or “Spice” is a popular drug of abuse that is heavily marketed to young teens and first-time drug users as “safe” and/or “legal” marijuana”. Most K2 preparations consist of plant materials laced with a mixture of one or more SCB compounds possessing psychoactive properties similar to those produced by Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive compound found in marijuana. However, in contrast to the low incidence of adverse effects reported following use of marijuana, recreational abuse of SCBs can additionally result in anxiety, psychosis, chest pain, seizures and death.
In marked contrast to K2/Spice products, marijuana contains only a single psychoactive compound Δ9-THC and a second natural constituent known as cannabidiol, that appears to blunt adverse effects produced by Δ9-THC. In fact, the beneficial combination of cannabidiol with Δ9-THC led to development of Sativex, a drug currently in clinical trials to treat a variety of indications including spasticity associated with multiple sclerosis.
In addition to Δ9-THC and cannabidiol, the cannabis plant contains hundreds of other phytocannabinoids and constituents not present in K2/Spice products that may help mitigate harmful and/or adverse effects ”
https://www.ncbi.nlm.nih.gov/pubmed/30319418
https://www.frontiersin.org/articles/10.3389/fphar.2018.01084/full
Molecular Imaging of the Cannabinoid System in Idiopathic Parkinson’s Disease.
“The endocannabinoid system is a modulator of neurotransmitter release and is involved in several physiological functions. Hence, it has been increasingly studied as a potential pharmacologic target of Parkinson’s disease.
Several preclinical and clinical studies evidenced a substantial rearrangement of the endocannabinoid system in the basal ganglia circuit following dopamine depletion. The endocannabinoid system has been additionally implicated in the regulation of neuroinflammation and neuroprotection through the activation of CB2 receptors, suggesting a potential target for disease modifying therapies in Parkinson’s disease.
In this chapter, current pharmacological and physiological knowledge on the role of the endocannabinoid system will be reviewed, focusing on preclinical studies animal models and clinical studies in patients with idiopathic Parkinson’s disease. The main strategies for imaging the brain cannabinoid system will be summarized to finally focus on in vivo imaging of patients with Parkinson’s disease.”
https://www.ncbi.nlm.nih.gov/pubmed/30314601
https://www.sciencedirect.com/science/article/pii/S0074774218300692?via%3Dihub
Neural stem cell lineage-specific cannabinoid type-1 receptor regulates neurogenesis and plasticity in the adult mouse hippocampus.
“Neural stem cells (NSCs) in the adult mouse hippocampus occur in a specific neurogenic niche, where a multitude of extracellular signaling molecules converges to regulate NSC proliferation as well as fate and functional integration. However, the underlying mechanisms how NSCs react to extrinsic signals and convert them to intracellular responses still remains elusive.
NSCs contain a functional endocannabinoid system, including the cannabinoid type-1 receptor (CB1).
To decipher whether CB1 regulates adult neurogenesis directly or indirectly in vivo, we performed NSC-specific conditional inactivation of CB1 by using triple-transgenic mice.
These results demonstrate that CB1 expressed in NSCs and their progeny controls neurogenesis in adult mice to regulate the NSC stem cell pool, dendritic morphology, activity-dependent plasticity, and behavior.”
https://www.ncbi.nlm.nih.gov/pubmed/30307491
https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhy258/5126794
Cannabidiol affects circadian clock core complex and its regulation in microglia cells.
“Cannabis is often used by consumers for sleep disorders.
Our study suggests that circadian rhythm in microglial cells is deregulated by CBD but not by THC.
It is consistent with clinical observations of the use of therapeutic cannabis to treat insomnia.”
Endocannabinoid Virodhamine is an Endogenous Inhibitor of Human Cardiovascular CYP2J2 Epoxygenase.
“The human body contains endogenous cannabinoids (endocannabinoids) that elicit similar effects as Δ9-tetrahydrocanabinol, the principal bioactive component of cannabis.
The endocannabinoid virodhamine (O-AEA) is the constitutional isomer of the well-characterized cardioprotective and anti-inflammatory endocannabinoid anandamide (AEA).
The chemical structures of O-AEA and AEA contain arachidonic acid (AA) and ethanolamine, however AA in O-AEA is connected to ethanolamine via an ester linkage whereas AA in AEA is connected through an amide linkage. We show that O-AEA is found at 9.6 fold higher levels than AEA in porcine left ventricle and is involved in regulating blood pressure and cardiovascular function.
On a separate note, the cytochrome P450 (CYP) epoxygenase CYP2J2 is the most abundant CYP in the heart where it catalyzes the metabolism of AA and AA-derived eCBs to bioactive epoxides that are involved in diverse cardiovascular functions. Herein, using competitive binding studies, kinetic metabolism measurements, molecular dynamics and wound healing assays we have shown that O-AEA is an endogenous inhibitor of CYP2J2 epoxygenase.
Together, the role of O-AEA as an endogenous eCB inhibitor of CYP2J2 may provide a new mode of regulation to control the activity of cardiovascular CYP2J2 in vivo and suggests a potential cross talk between the cardiovascular endocannabinoids and cytochrome P450 system.”
A systematic review on the neuroprotective perspectives of beta-caryophyllene.
“Beta (β)-caryophyllene (BCAR) is a major sesquiterpene of various plant essential oils reported for several important pharmacological activities, including antioxidant, anti-inflammatory, anticancer, cardioprotective, hepatoprotective, gastroprotective, nephroprotective, antimicrobial, and immune-modulatory activity. Recent studies suggest that it also possesses neuroprotective effect.
This study reviews published reports pertaining to the neuropharmacological activities of BCAR. Databases such as PubMed, Scopus, MedLine Plus, and Google Scholar with keywords “beta (β)-caryophyllene” and other neurological keywords were searched. Data were extracted by referring to articles with information about the dose or concentration/route of administration, test system, results and discussion, and proposed mechanism of action.
A total of 545 research articles were recorded, and 41 experimental studies were included in this review, after application of exclusion criterion. Search results suggest that BCAR exhibits a protective role in a number of nervous system-related disorders including pain, anxiety, spasm, convulsion, depression, alcoholism, and Alzheimer’s disease.
Additionally, BCAR has local anesthetic-like activity, which could protect the nervous system from oxidative stress and inflammation and can act as an immunomodulatory agent. Most neurological activities of this natural product have been linked with the cannabinoid receptors (CBRs), especially the CB2R. This review suggests a possible application of BCAR as a neuroprotective agent.”
https://www.ncbi.nlm.nih.gov/pubmed/30281175
“β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis.” http://www.ncbi.nlm.nih.gov/pubmed/23138934