Cnr2 is one of two cannabinoid receptors known to regulate bone metabolism. Here, we compared the whole bone properties of femora and tibiae from three-month-old Cnr2−/− mice with wild-type controls using a C57BL/6 background. Bending stiffness was measured by three-point bending. The elastic modulus, density and mineral content were measured using ultrasound, Archimedes’ principle and ashing. Micro-CT was used to measure the second moment of area, inner and outer perimeters of the cortical shaft and trabecular parameters. Deleting Cnr2 increased the bending stiffness by increasing the second moment of area. Bone from affected male mice had a greater modulus than controls, although no difference...

Endogenous and synthetic cannabinoids exert antiproliferative and proapoptotic effects in various types of cancer and in mantle cell lymphoma (MCL). In this study, we evaluated the expression of cannabinoid receptors type 1 and type 2 (CB1 and CB2) in nonHodgkin lymphomas of B cell type (n 5 62). A majority of the lymphomas expressed higher mRNA levels of CB1 and/or CB2 as compared to reactive lymphoid tissue. With the exception of MCL, which uniformly overexpresses both CB1 and CB2, the levels of cannabinoid receptors within other lymphoma entities were highly variable, ranging from 0.1 to 224 times the expression in reactive lymph nodes. Low...

Abstract Two proteins with seven transmembrane-spanning domains typical of guanosine-nucleotide-binding-protein-coupled receptors have been identified as cannabinoid receptors; the central cannabinoid receptor, CB1, and the peripheral cannabinoid receptor, CB2, initially described in rat brain and spleen, respectively. Here, we report the distribution patterns for both CB1 and CB2 transcripts in human immune cells and in several human tissues, as analysed using a highly sensitive and quantitative PCR-based method. CB1 was mainly expressed in the central nervous system and, to a lower extent, in several peripheral tissues such as adrenal gland, heart, lung, prostate, uterus, ovary, testis, bone marrow, thymus and tonsils. In contrast, the CB2...

The development of new therapeutic strategies is essential for the management of gliomas, one of the most malignant forms of cancer. We have shown previously that the growth of the rat glioma C6 cell line is inhibited by psychoactive cannabinoids (I. Galve-Roperh et al., Nat. Med., 6: 313–319, 2000). These compounds act on the brain and some other organs through the widely expressed CB1 receptor. By contrast, the other cannabinoid receptor subtype, the CB2 receptor, shows a much more restricted distribution and is absent from normal brain. Here we show that local administration of the selective CB2 agonist JWH-133 at 50 mg/day to Rag-22/2...

BACKGROUND: We have previously shown that cannabinoids induce growth inhibition and apoptosis in prostate cancer PC-3 cells, which express high levels of cannabinoid receptor types 1 and 2 (CB1 and CB2). In this study, we investigated the role of CB2 receptor in the anti-proliferative action of cannabinoids and the signal transduction triggered by receptor ligation. METHODS: The human prostate cancer cell lines, namely PC-3, DU-145 and LNCaP, were used for this study. Cell proliferation was measured using MTT proliferation assay, [3 H]-thymidine incorporation assay and cell-cycle study by flow cytometry. Ceramide quantification was performed using the DAG kinase method. The CB2 receptor was silenced...

Introduction: Cannabinoid compounds, both nonspecific as well as agonists selective for either cannabinoid receptor 1 (CB1 ) or cannabinoid receptor 2 (CB2 ), have been shown to modulate the tumor microenvironment by inducing apoptosis in tumor cells in several model systems. The mechanism of this modulation remains only partially delineated, and activity induced via the CB1 and CB2 receptors may be distinct despite significant sequence homology and structural similarity of ligands. Methods: The CB2 -selective agonist JWH-015 was used to investigate mechanisms downstream of CB2 activation in mouse and human breast cancer cell lines in vitro and in a murine mammary tumor model. Results:...

The goal of the current investigation was to evaluate the mechanisms through which administration of a selective cannabinoid-2 (CB2) agonist (O-1966) modifies inflammatory responses and helps to improve function following spinal cord injury. A comparison of motor function, autonomic function, and inflammatory responses was made between animals treated with O-1966 (5 mg/kg IP) and animals treated with vehicle 1 h and 24 h following contusion injury to the spinal cord. Motor function was significantly improved in the treated animals at each time point during the 14 days of evaluation. The percentage of animals able to spontaneously void their bladder was also greater over the...

Cannabinoids, the active components of marijuana and their endogenous counterparts, act on the brain and many other organs through the widely expressed CB1 cannabinoid receptor. In contrast, the CB2 cannabinoid receptor is abundant in the immune system and shows a restricted expression pattern in brain cells. CB2-selective agonists are, therefore, very attractive therapeutic agents as they do not cause CB1-mediated psychoactive effects. CB2 receptor expression in brain has been partially examined in differentiated cells, while its presence and function in neural progenitor cells remain unknown. Here we show that the CB2 receptor is expressed, both in vitro and in vivo, in neural progenitors from...

The endogenous cannabinoids bind to and activate two G proteincoupled receptors, the predominantly central cannabinoid receptor type 1 (CB1) and peripheral cannabinoid receptor type 2 (CB2). Whereas CB1 mediates the cannabinoid psychotropic, analgesic, and orectic effects, CB2 has been implicated recently in the regulation of liver fibrosis and atherosclerosis. Here we show that CB2-deficient mice have a markedly accelerated age-related trabecular bone loss and cortical expansion, although cortical thickness remains unaltered. These changes are reminiscent of human osteoporosis and may result from differential regulation of trabecular and cortical bone remodeling. The CB2 / phenotype is also characterized by increased activity of trabecular osteoblasts (bone-forming...

Cough, a reflex defense mechanism, is a common symptom of many airway inflammatory diseases. At present there are no satisfactory treatments for cough that have an acceptable side effect profile. Recent data have described the inhibitory effect of selective cannabinoid CB2 receptor agonists on sensory nerve activity in vitro and the cough reflex in a guinea pig model. CB2 receptor expression is limited in the central nervous system (CNS) and hence the development of selective agonists may provide a new therapeutic strategy for treatment of cough devoid of the CNS-mediated side effects that are normally associated with nonselective cannabinoid agonists.