anandamide and Edema

We showed previously that inhibiting fatty acid amide hydrolase (FAAH), an endocannabinoid degrading enzyme, and transient receptor potential vanilloid type-1 (TRPV1) channels with the same molecule, the naturally occurring N-arachidonoyl-serotonin (AA-5-HT), produces more efficacious anti-nociceptive and anti-hyperalgesic actions than the targeting of FAAH or TRPV1 alone. We also reported the synthesis of some piperazinyl carbamates as "dual" FAAH inhibitors and either antagonists at TRPV1 or agonists/desensitizers of the transient receptor potential ankyrin type-1 (TRPA1) cannel, another target for analgesic drugs. We investigated here if two such compounds, the FAAH/TRPV1 blocker OMDM198 and the FAAH inhibitor/TRPA1 agonist, OMDM202, exert anti-nociceptive actions in the formalin test of pain in mice, and through what mechanism. Both compounds inhibited the second phase of the response to formalin, the effect being maximal at 3 mg/kg, i.p. Antagonism of CB1 or CB2 receptors with AM251 or AM630 (1 mg/kg, i.p.), respectively, reversed this effect. A TRPV1 agonist, palvanil (0.1 mg/kg, i.p.), also reversed the analgesic effect of OMDM198. OMDM202 action was also antagonized by a per se inactive dose of the selective TRPA1 blocker, AP-18 (0.05 mg/kg, i.p.), but not by a TRPV1 antagonist. AP-18 at higher doses (0.1-0.2 mg/kg) inhibited both the first and second phase of the formalin response. The effects of OMDM198 and OMDM202 were accompanied by elevation of anandamide levels in the spinal cord. OMDM198 (0.1-5.0 mg/kg, i.p.) also reversed carrageenan-induced oedema and thermal hyperalgesia in mice with efficacy similar to that of AA-5-HT. These data suggest that "dual" fatty acid amide hydrolase and transient receptor potential channel modulators should be clinically evaluated as novel analgesics.

Topics: Amidohydrolases; Analgesics; Animals; Arachidonic Acids; Carbamates; Edema; Endocannabinoids; Male; Mice; Mice, Inbred C57BL; Pain; Pain Measurement; Polyunsaturated Alkamides; Transient Receptor Potential Channels; TRPA1 Cation Channel; TRPV Cation Channels

Hemopressin, a nonapeptide (PVNFKFLSH: HP) derived from the α chain of hemoglobin was shown to interact specifically with brain cannabinoid CB(1) receptors. Therefore, it seems to be the only peptide structure with cannabinoid activities. Our goal in this study was to further characterize this peptide and to clarify the antinociceptive potency of the polyunsaturated fatty acid derivates, 2-arachidonoyl-glycerol (2-AG) and anandamide, by investigating their effects on mechanical allodynia at the spinal level.. HP was prepared on solid phase by in situ neutralization. After chronic intrathecal catheterization, mechanical hypersensitivity was produced in male Wistar rats by injection of carrageenan (300 μg/30 μL) into the tibiotarsal joint of one of the hind legs. Three hours after carrageenan administration, the ligands were administered intrathecally. The mechanical threshold was assessed using a dynamic aesthesiometer.. 2-AG (1-200 μg) and anandamide (10-200 μg) decreased carrageenan-induced mechanical allodynia in a dose-dependent manner, whereas HP had no antinociceptive effect in a wide dose range (0.3-30 μg). The effect of 2-AG was prevented by the CB(1) receptor antagonist AM 251, but not by the CB(2) antagonist SSR144528-2. HP (3 and 30 μg) also inhibited the effect of 2-AG. None of the ligands influenced the degree of edema.. HP posttreatment had no effect on mechanical allodynia, whereas spinally injected 2-AG and anandamide were potent drugs.

Topics: Analgesics; Animals; Arachidonic Acids; Arthralgia; Arthritis, Experimental; Cannabinoid Receptor Modulators; Carrageenan; Dose-Response Relationship, Drug; Edema; Endocannabinoids; Glycerides; Hemoglobins; Hindlimb; Injections, Spinal; Joints; Male; Pain Measurement; Pain Threshold; Peptide Fragments; Polyunsaturated Alkamides; Rats; Rats, Wistar; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Time Factors

While it has long been recognized that Delta(9)-tetrahydrocannabinol (THC), the primary psychoactive constituent of cannabis, and other cannabinoid receptor agonists possess anti-inflammatory properties, their well known CNS effects have dampened enthusiasm for therapeutic development. On the other hand, genetic deletion of fatty acid amide hydrolase (FAAH), the enzyme responsible for degradation of fatty acid amides, including endogenous cannabinoid N-arachidonoyl ethanolamine (anandamide; AEA), N-palmitoyl ethanolamine (PEA), N-oleoyl ethanolamine (OEA), and oleamide, also elicits anti-edema, but does not produce any apparent cannabinoid effects. The purpose of the present study was to investigate whether exogenous administration of FAAs would augment the anti-inflammatory phenotype of FAAH (-/-) mice in the carrageenan model. Thus, we evaluated the effects of the FAAs AEA, PEA, OEA, and oleamide in wild-type and FAAH (-/-) mice. For comparison, we evaluated the anti-edema effects of THC, dexamethasone (DEX), a synthetic glucocorticoid, diclofenac (DIC), a nonselective cyclooxygenase (COX) inhibitor, in both genotypes. A final study determined if tolerance to the anti-edema effects of PEA occurs after repeated dosing. PEA, THC, DEX, DIC elicited significant decreases in carrageenan-induced paw edema in wild-type mice. In contrast OEA produced a less reliable anti-edema effect than these other drugs, and AEA and oleamide failed to produce any significant decreases in paw edema. Moreover, none of the agents evaluated augmented the anti-edema phenotype of FAAH (-/-) mice, suggesting that maximal anti-edema effects had already been established. PEA was the most effective FAA in preventing paw edema and its effects did not undergo tolerance. While the present findings do not support a role for AEA in preventing carrageenan-induced edema, PEA administration and FAAH blockade elicited anti-edema effects of an equivalent magnitude as produced by THC, DEX, and DIC in this assay.

Topics: Amidohydrolases; Analysis of Variance; Animals; Arachidonic Acids; Cannabinoids; Carrageenan; Dexamethasone; Disease Models, Animal; Dose-Response Relationship, Drug; Dronabinol; Drug Interactions; Edema; Endocannabinoids; Ethanolamines; Female; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Oleic Acids; Polyunsaturated Alkamides

We describe herein the discovery of LASSBio-881 (3c) as a novel in vivo antinociceptive, anti-inflammatory, and in vitro antiproliferative and antioxidant compound, with a cannabinoid ligand profile. We observed that LASSBio-881 (3c) was able to bind to CB1 receptors (71% at 100microM) and also to inhibit T-cell proliferation (66% at 10microM) probably by binding to CB2 receptors, in a non-proapoptotic manner, different from anandamide (1). It was also demonstrated that LASSBio-881 (3c) had an important antioxidant profile toward free radicals (DPPH and hydroxyl), probably due to its particular redox behavior, which reflects the presence of both nitro and 3,5-di-tert-butyl-4-hydroxyphenyl sub-units, as demonstrated by cyclic voltammetry studies. In addition, we showed that these structural sub-units are essential for the observed pharmacological activity.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Antioxidants; Arachidonic Acid; Arachidonic Acids; Biphenyl Compounds; Brain; Cannabinoid Receptor Modulators; Carrageenan; Cell Proliferation; Edema; Endocannabinoids; Female; Formaldehyde; Free Radical Scavengers; Hydrazines; Hydrazones; Ligands; Male; Mice; Models, Molecular; Pain; Picrates; Polyunsaturated Alkamides; Pyridines; Rats; Rats, Wistar; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Structure-Activity Relationship; Superoxides; T-Lymphocytes

Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit fatty-acid amide hydrolase (FAAH), the enzyme responsible for the metabolism of anandamide, an endocannabinoid. It has been suggested that the mechanisms of action of NSAIDs could be due to inhibition of cyclooxygenase (COX) and also to an increase in endocannabinoid concentrations. In a previous study we have demonstrated that the local analgesic interaction between anandamide and ibuprofen (a non-specific COX inhibitor) was synergistic for the acute and inflammatory phases of the formalin test. To test this hypothesis further, we repeated similar experiments with rofecoxib (a selective COX-2 inhibitor) and also measured the local concentrations of anandamide, and of two fatty-acid amides, oleoylethanolamide and palmitoylethanolamide. We established the ED(50) for anandamide (34.52 pmol+/-17.26) and rofecoxib (381.72 pmol+/-190.86) and showed that the analgesic effect of the combination was synergistic. We also found that paw tissue levels of anandamide, oleoylethanolamide and palmitoylethanolamide were significantly higher when anandamide was combined with NSAIDs and that this effect was greater with rofecoxib. In conclusion, local injection of anandamide or rofecoxib was antinociceptive in a test of acute and inflammatory pain and the combination of anandamide with rofecoxib was synergistic. Finally, locally injected anandamide with either NSAID (ibuprofen or rofecoxib) generates higher amount of fatty-acid ethanolamides. The exact comprehension of the mechanisms involved needs further investigation.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arachidonic Acids; Capsaicin; Chromatography, High Pressure Liquid; Cyclooxygenase 2 Inhibitors; Dose-Response Relationship, Drug; Drug Synergism; Edema; Endocannabinoids; Formaldehyde; Ibuprofen; Lactones; Male; Mass Spectrometry; Nitrobenzenes; Pain Measurement; Peripheral Nervous System; Polyunsaturated Alkamides; Rats; Rats, Wistar; Sulfonamides; Sulfones; TRPV Cation Channels

Central antinociceptive effects of cannabinoids have been well documented. However, relatively little is known about the peripheral effects of the cannabinoids on inflammation. In the present study, we evaluated the effects of peripherally administered cannabinoids on three indices of inflammation: carrageenan-induced thermal hyperalgesia, carrageenan-induced edema, and capsaicin-induced plasma extravasation. In addition, we determined the effect of cannabinoids on capsaicin-evoked neuropeptide release from isolated rat hindpaw skin. Our results indicate that cannabinoids produce antihyperalgesia via interaction with a peripheral CB1 receptor. Peripheral, but not systemic, administration of 0.01 ng anandamide inhibited the induction of hyperalgesia. Peripheral administration of anandamide also attenuated hyperalgesia after its development via interaction with the CB1 cannabinoid receptor subtype as indicated by its reversal with the CB1 receptor antagonist SR 141716A. Additionally, peripheral, but not systemic, administration of 0.01 ng anandamide inhibited edema. Peripherally administered cannabinoids also interacted with CB1 receptors to inhibit capsaicin-evoked plasma extravasation into the hindpaw. One potential mechanism for the anti-inflammatory actions of the cannabinoids is the inhibition of neurosecretion from the peripheral terminals of nociceptive primary afferent fibers. This hypothesis is supported by the finding that anandamide inhibited capsaicin-evoked release of calcitonin gene-related peptide from isolated hindpaw skin. Collectively, these results indicate that cannabinoids reduce inflammation via interaction with a peripheral CB1 receptor. A potential mechanism for this effect is the inhibition of neurosecretion from capsaicin-sensitive primary afferent fibers.

Topics: Animals; Anti-Inflammatory Agents; Arachidonic Acids; Calcitonin Gene-Related Peptide; Capillary Permeability; Capsaicin; Carrageenan; Edema; Endocannabinoids; Hindlimb; Hyperalgesia; Male; Polyunsaturated Alkamides; Rats; Rats, Sprague-Dawley; Receptors, Cannabinoid; Receptors, Drug; Skin