jwh-133 and Myocardial-Infarction

The administration of cannabinoid receptor 2 (CB2R) agonist has been reported to produce a cardioprotective effect against the pathogenesis and progression of myocardial infarction (MI). Here in this study, we investigated the specific mechanism related to inflammatory suppression. JWH-133 was used for the activation of CB2R. MI mice models and cardiomyocytes under oxygen-glucose deprivation (OGD) challenge were used for the in vivo and in vitro studies, respectively. Detection of cardiac infarct size and levels of myocardial enzymes as well as echocardiographic examination were applied to assess MI severity and cardiac function. Cell viability and lactate dehydrogenase (LDH) release were detected in vitro. Real-time-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to detect the levels of proinflammatory cytokines. Western blot was used for the analysis of the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation. We found that the administration of CB2R agonist attenuated the severity of MI through reducing infarct size ratio and levels of myocardial enzymes and improved cardiac function in ejection fraction (EF), fractional shortening (FS), left ventricular end-systolic diameter (LVESD), and left ventricular end-diastolic diameter (LVEDD) in MI mice. JWH-133 also produced a cardioprotective effect in murine primary cardiomyocytes by improving cell viability and LDH release. JWH-133 largely reduced the production and secretion of proinflammatory cytokines, which was significantly attenuated by AM630. HU308 showed the same effects as JWH-133. Taken together, we demonstrated for the first time the cardioprotective effect of CB2R agonist and its NLRP3 inflammasome-related mechanism in MI.

Topics: Animals; Cannabinoids; Cardiotonic Agents; Cell Survival; Inflammasomes; Mice; Myocardial Infarction; Myocytes, Cardiac; NLR Family, Pyrin Domain-Containing 3 Protein; Receptor, Cannabinoid, CB2

The aim of this study was to investigate whether the mitochondrial permeability transition pore (MPTP) opening was involved in the protective effects of CB2 receptor against ischemia-reperfusion (I-R) injury. For this, isolated perfused rat hearts were subjected to 30 min global ischemia followed by 120 min reperfusion, and left ventricle function was recorded. At the end of reperfusion, the infarct size in the hearts was measured by staining with triphenyltetrazolium chloride. MPTP opening and the mitochondrial membrane potential (ΔΨ(m)) were measured by flow cytometry. Western blot analysis of cytochrome c in the mitochondrion and cytosol, as well as ERK1/2 and p-ERK1/2 were performed. Administration of CB2 receptor agonist JWH133 before ischemia significantly improved the recovery of cardiac ventricular function during reperfusion, increased coronary flow, reduced infarct size, prevented the loss of ΔΨ(m) and MPTP opening, reduced the release of cytochrome c from mitochondria, and increased levels of p-ERK1/2. These effects of JWH133 were abolished by pretreatment with CB2 receptor antagonist AM630, or ERK1/2 inhibitor PD98059. Furthermore, JWH133 reversed the MPTP opening induced by atractyloside. The protective effect of JWH133 on the heart against I-R injury may be through increased ERK1/2 phosphorylation, inhibiting MPTP opening.

Topics: Animals; Cannabinoids; Cytochromes c; Male; MAP Kinase Signaling System; Mitochondria, Heart; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Myocardial Infarction; Myocardial Reperfusion Injury; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB2

Preventive treatment with cannabinoid agonists has been reported to reduce the infarct size in a mouse model of myocardial ischemia/reperfusion. Here we investigated the possible cardioprotective effect of selective CB(2) cannabinoid receptor activation during ischemia. We performed left coronary artery ligature in C57Bl/6 mice for 30 min, followed by 24 h of reperfusion. Five minutes before reperfusion, mice received intraperitoneal injection of the CB(2) selective agonist JWH-133 (20 mg/kg) or vehicle. Infarct size was assessed histologically and by cardiac troponin I (cTnI) ELISA. Immunohistochemical analysis of leukocyte infiltration, oxidative stress in situ quantification, real-time RT-PCR analysis of inflammatory mediators as well as western blots for kinase phosphorylation was also performed. In addition, we studied chemotaxis and integrin expression of human neutrophils in vitro. JWH-133 significantly reduced the infarct size (I/area at risk: 19.27%+/-1.91) as compared to vehicle-treated mice (31.77%+/-2.7). This was associated with a reduction of oxidative stress and neutrophil infiltration in the infarcted myocardium, whereas activation of ERK 1/2 and STAT-3 was increased. Preinjection of PI3K inhibitor LY294002, MEK 1/2 inhibitor U0126 and JAK-2 inhibitor AG-490 partially abrogated the JWH-133 mediated infarct size reduction. No changes in cardiac CXCL1, CXCL2, CCL3, TNF-alpha, and ICAM-1 expression levels were found. Furthermore, JWH-133 inhibited the TNF-alpha induced chemotaxis and integrin CD18/CD11b (Mac-1) upregulation on human neutrophils. Our data suggest that JWH-133 administration during ischemia reduces the infarct size in a mouse model of myocardial ischemia/reperfusion through a direct cardioprotective activity on cardiomyocytes and neutrophils.

Topics: Animals; Cannabinoids; CD11b Antigen; Cell Movement; Chemotactic Factors; Disease Models, Animal; Humans; Intercellular Adhesion Molecule-1; Intracellular Space; Mice; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Neutrophils; Oxidative Stress; Reactive Oxygen Species; Receptor, Cannabinoid, CB2; Signal Transduction; Tumor Necrosis Factor-alpha