interleukin-8 and anandamide

Phytocannabinoids modulate inflammatory responses by regulating the production of cytokines in several experimental models of inflammation. Cannabinoid type-2 (CB

Topics: Anti-Inflammatory Agents; Arachidonic Acids; Cannabidiol; Cell Line; Chemokine CCL8; Dermatitis, Allergic Contact; Endocannabinoids; Humans; Interleukin-6; Interleukin-8; Polyunsaturated Alkamides; Tumor Necrosis Factor-alpha

Cannabinoids are known to possess both anti-inflammatory and neuroprotective effects. In the present study, we have investigated the ability of cannabinoids to inhibit the transmigration of neutrophils in response to chemotaxic stimuli. The cannabinoid receptor agonist WIN 55,212-2 ((R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)-pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate) significantly decreased the number of migrating neutrophils across a monolayer of tumour necrosis factor alpha (TNF-alpha) activated ECV304 cells at concentrations >or=1 microM. In contrast, the agonists HU210 and CP 55,940 (0.01-1 microM) and the endocannabinoid anandamide (0.1-10 microM) were without significant effect on the response to TNF-alpha. The ability of WIN 55,212-2 to reduce the neutrophil transmigration was still seen in the presence of the cannabinoid CB(1) receptor antagonist/inverse agonist AM251 (0.1-1 microM) and the cannabinoid CB(2) receptor antagonist/inverse agonist AM630 (0.1-1 microM). TNF-alpha treatment of ECV304 cells caused release of interleukin-8 (IL-8), but WIN 55,212-2 did not affect either the ability of neutrophils to migrate across chemotaxis plates in response to an IL-8 stimulus, or to change the percentage of CXC 1 and CXC 2 receptors expressed by the neutrophils. WIN 55,212-2 at a concentration of 1 microM, but not at lower concentrations, produced a significant inhibition of IL-8 release from ECV304 cells in response to TNF-alpha-stimulation. Thus WIN 55,212-2 reduces the transmigration of neutrophils across a monolayer of TNF-alpha-activated ECV304 cells by an indirect action upon the release of IL-8 and/or other chemokine release from the ECV304 cells, and that this effect is brought about mainly by a cannabinoid CB receptor-independent mechanism.

Topics: Analysis of Variance; Arachidonic Acids; Benzoxazines; Cannabinoid Receptor Agonists; Cannabinoid Receptor Antagonists; Cell Line; Cell Movement; Chemotaxis; Cyclohexanols; Dose-Response Relationship, Drug; Dronabinol; Endocannabinoids; Endothelial Cells; Flow Cytometry; Humans; Indoles; Interleukin-8; L-Lactate Dehydrogenase; Morpholines; Naphthalenes; Neutrophils; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Receptors, Cannabinoid; Receptors, Interleukin-8A; Receptors, Interleukin-8B; Thapsigargin; Tumor Necrosis Factor-alpha

2-Arachidonoylglycerol is an endogenous ligand for the cannabinoid receptors (CB1 and CB2). Previously, we provided evidence that 2-arachidonoylglycerol, but not anandamide (N-arachidonoylethanolamine), is the true natural ligand for the cannabinoid receptors. In the present study, we examined in detail the effects of 2-arachidonoylglycerol on the production of chemokines in human promyelocytic leukemia HL-60 cells. We found that 2-arachidonoylglycerol induced a marked acceleration in the production of interleukin 8. The effect of 2-arachidonoylglycerol was blocked by treatment of the cells with SR144528, a cannabinoid CB2 receptor antagonist, indicating that the effect of 2-arachidonoylglycerol is mediated through the CB2 receptor. Augmented production of interleukin 8 was also observed with CP55940, a synthetic cannabinoid, and an ether-linked analog of 2-arachidonoylglycerol. On the other hand, neither anandamide nor the free arachidonic acid induced the enhanced production of interleukin 8. A similar effect of 2-arachidonoylglycerol was observed in the case of the production of macrophage-chemotactic protein-1. The accelerated production of interleukin 8 by 2-arachidonoylglycerol was observed not only in undifferentiated HL-60 cells, but also in HL-60 cells differentiated into macrophage-like cells. Noticeably, 2-arachidonoylglycerol and lipopolysaccharide acted synergistically to induce the dramatically augmented production of interleukin 8. These results strongly suggest that the CB2 receptor and its physiological ligand, i.e., 2-arachidonoylglycerol, play important regulatory roles such as stimulation of the production of chemokines in inflammatory cells and immune-competent cells. Detailed studies on the cannabinoid receptor system are thus essential to gain a better understanding of the precise regulatory mechanisms of inflammatory reactions and immune responses.

Topics: Arachidonic Acid; Arachidonic Acids; Blotting, Northern; Calcitriol; Camphanes; Cell Differentiation; Chemokine CCL2; Chemokines; Cyclohexanols; Dose-Response Relationship, Drug; Endocannabinoids; Enzyme-Linked Immunosorbent Assay; Gene Expression; Glycerides; HL-60 Cells; Humans; Interleukin-8; Lipopolysaccharides; Polyunsaturated Alkamides; Pyrazoles; Receptor, Cannabinoid, CB2; RNA, Messenger; Time Factors