Cannabinoid receptor type 2 agonist JWH-133 decreases cathepsin B secretion and neurotoxicity from HIV-infected macrophages

HIV-associated neurocognitive disorders (HAND) are prevalent despite combined antiretroviral therapy (cART), affecting 52% of people living with HIV. Our laboratory has demonstrated increased expression of cathepsin B (CATB) in postmortem brain tissue with HAND. Increased secretion of CATB from in vitro HIV-infected monocyte-derived macrophages (MDM) induces neurotoxicity. Activation of cannabinoid receptor type 2 (CB2R) inhibits HIV-1 replication in macrophages and the neurotoxicity induced by viral proteins. However, it is unknown if CB2R agonists affect CATB secretion and neurotoxicity in HIV-infected MDM. We hypothesized that HIV-infected MDM exposed to CB2R agonists decrease CATB secretion and neurotoxicity. Primary MDM were inoculated with HIV-1ADA and treated with selective CB2R agonists JWH-133 and HU-308. HIV-1 p24 and CATB levels were determined from supernatants using ELISA. MDM were pre-treated with a selective CB2R antagonist SR144528 before JWH-133 treatment to determine if CB2R activation is responsible for the effects. Neuronal apoptosis was assessed using a TUNEL assay. Results show that both agonists reduce HIV-1 replication and CATB secretion from MDM in a time and dose-dependent manner and that CB2R activation is responsible for these effects. Finally, JWH-133 decreased HIV/MDM-CATB induced neuronal apoptosis. Our results suggest that agonists of CB2R represent a potential therapeutic strategy against HIV/MDM-induced neurotoxicity.

Development of [18F]LU14 for PET Imaging of Cannabinoid Receptor Type 2 in the Brain

Cannabinoid receptors type 2 (CB2R) represent an attractive therapeutic target for neurodegenerative diseases and cancer. Aiming at the development of a positron emission tomography (PET) radiotracer to monitor receptor density and/or occupancy during a CB2R-tailored therapy, we herein describe the radiosynthesis of cis-[18F]1-(4-fluorobutyl-N-((1s,4s)-4-methylcyclohexyl)-2-oxo-1,2-dihydro-1,8-naphthyridine-3-carboxamide ([18F]LU14) starting from the corresponding mesylate precursor. The first biological evaluation revealed that [18F]LU14 is a highly affine CB2R radioligand with >80% intact tracer in the brain at 30 min p.i. Its further evaluation by PET in a well-established rat model of CB2R overexpression demonstrated its ability to selectively image the CB2R in the brain and its potential as a tracer to further investigate disease-related changes in CB2R expression.

Cannabinoid receptor type 2 ligands: an analysis of granted patents since 2010

The G-protein-coupled cannabinoid receptor type 2 (CB2R) is a key element of the endocannabinoid (EC) system. EC/CB2R signaling has significant therapeutic potential in major pathologies affecting humans such as allergies, neurodegenerative disorders, inflammation or ocular diseases. CB2R agonism exerts anti-inflammatory and tissue protective effects in preclinical animal models of cardiovascular, gastrointestinal, liver, kidney, lung and neurodegenerative disorders. Existing ligands can be subdivided into endocannabinoids, cannabinoid-like and synthetic CB2R ligands that possess various degrees of potency on and selectivity against the cannabinoid receptor type 1. This review is an account of granted CB2R ligand patents from 2010 up to the present, which were surveyed using Derwent Innovation®.

Endocannabinoidome and its role in neurological disorders-A comprehensive update of existing literature

Medical benefits of cannabis and related compounds is widely known. Discovery of psychotropic plant cannabinoid Δ9-tetrahydrocannabinol have urged researchers to study more about the cannabinoid system and related therapeutics in the field of neurology and medicine. Where activation of cannabinoid receptor type 1 (CB1R) yielded in unwanted and serious side effects, discovery of cannabinoid receptor type 2 (CB2R) and its ligands gave a new hope. Till now there is limited success in this field because of complex expanded endocannabinoid system comprising of receptors, ligands and enzymes. In this review we will update about the role of endocannabinoidome relevant to neurological disorders.

Premature delivery and cannabinoid receptor expression in the placenta after delivery: an observational study.

Objective: To investigate the relationship between cannabinoid receptor expression within the placenta after delivery and the problem of preterm delivery. Design, setting, and participants: The retrospective, observational study was conducted on a multicenter material of 150 women. The study group included 115 women after premature delivery. The control group consisted of 35 women after term delivery. Methods. To determine the expression of cannabinoid receptors after the end of the third stage of labour, several sections were taken from the placenta. RNA isolation, reverse transcription, and Real-Time PCR were performed to assess the expression of the cannabinoid receptors in the placenta. Results: Cannabinoid receptor type 2 expression was lower in the placentas of women after preterm delivery. Urinary tract infections and bleeding at any stage of pregnancy occurred statistically more frequently in the study group and correlated with cannabinoid receptor type 2 expression. In the study group, the history of preterm labor, history of intrauterine fetal deaths, pregnancies terminated by a Caesarean section, and uterine tenderness correlated with lower expression of cannabinoid receptor type 2 and 1a. Conclusions: Cannabinoid receptors mRNA were present in human placental tissue during pregnancy. Decreased cannabinoid receptor type 2 expression in preterm delivered placentas should be further investigated, as perinatal endocannabinoid receptor expression could serve as a predicting tool of preterm birth. For example, liquid-based cytology could be used as a noninvasive perinatal method of measuring the expression level of cannabinoid receptors in decidual cells during pregnancy. KEYWORDS: Cannabinoid receptor; CB2; endocannabinoid system; preterm delivery; PTB