Publications (25) View all
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Article: The Interaction of Fatty Acid Amide Hydrolase (FAAH) Inhibitors with an Anandamide Carrier Protein Using (19) F-NMR.
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ABSTRACT: It has been reported that the endocannabinoid anandamide (AEA) binds to a class of fatty acid-binding proteins and serum albumin which can serve as carrier proteins and potentiate the cellular uptake of AEA and its intracellular translocation. Here, we employed (19)F nuclear magnetic resonance spectroscopy to study the interactions of serum albumin with two inhibitors of fatty acid amide hydrolase (FAAH), the enzyme involved in the deactivation of anandamide. We found that, for both inhibitors AM5206 and AM5207, the primary binding site on serum albumin is drug site 1 located at subdomain IIA. Neither inhibitor binds to drug site 2. While AM5207 binds exclusively to drug site 1, AM5206 also interacts with other fatty acid-binding sites on serum albumin. Additionally, AM5206 has an affinity for serum albumin approximately one order of magnitude higher than that of AM5207. The data suggest that interactions of FAAH inhibitors with albumin may provide added advantages for their ability to modulate endocannabinoid levels for a range of applications including analgesia, antiemesis, and neuroprotection.The AAPS Journal 01/2013; · 5.09 Impact Factor -
Article: Sulfonyl Fluoride Inhibitors of Fatty Acid Amide Hydrolase.
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ABSTRACT: Sulfonyl fluorides are known to inhibit esterases. Early work from our laboratory has identified hexadecyl sulfonylfluoride (AM374) as a potent in vitro and in vivo inhibitor of fatty acid amide hydrolase (FAAH). We now report on later generation sulfonyl fluoride analogs that exhibit potent and selective inhibition of FAAH. Using recombinant rat and human FAAH we show that 5-(4-hydroxyphenyl)pentanesulfonyl fluoride (AM3506) has similar inhibitory activity for both the rat and the human enzyme, while rapid dilution assays and mass spectrometry analysis suggest that the compound is a covalent modifier for FAAH and inhibits its action in an irreversible manner. Our SAR results are highlighted by molecular docking of key analogs.Journal of Medicinal Chemistry 10/2012; · 4.80 Impact Factor -
Article: Δ9-Tetrahydrocannabinol acts as a partial agonist/antagonist in mice.
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ABSTRACT: Δ-Tetrahydrocannabinol (THC) has been characterized as a partial agonist at cannabinoid CB1 receptors in vitro; however, it often produces the same maximum effects in vivo as other cannabinoid agonists. This study was carried out to determine whether THC would antagonize the hypothermic effects of another cannabinoid agonist, AM2389, in mice. Male mice were injected with 1-100 mg/kg THC, 0.01-0.1 mg/kg AM2389, or a combination of 30 mg/kg THC and 0.1-1.0 mg/kg AM2389, and rectal temperature was recorded for up to 12 h after injection. THC reduced the temperature by 5.6°C at a dose of 30 mg/kg; further increases in the dose did not produce larger effects, indicating a plateau in the THC dose-effect function. AM2389 reduced temperature by 9.0°C at a dose of 0.1 mg/kg. One hour pretreatment with 30 mg/kg THC attenuated the hypothermic effects of 0.1 mg/kg AM2389; a 10-fold higher dose, 1.0 mg/kg AM2389, was required to further decrease temperature, reflecting a five-fold rightward shift of the lower portion of the AM2389 dose-effect function following THC pretreatment. These results indicate that, in an assay of mouse hypothermia, THC exerts both agonist and antagonist effects following acute administration, and mark the first demonstration of partial agonist/antagonist effects of THC in vivo.Behavioural pharmacology 10/2012; · 2.85 Impact Factor -
Article: Diuretic effects of cannabinoids.
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ABSTRACT: In vivo effects of cannabinoid (CB) agonists are often assessed using four well-established measures: locomotor activity, hypothermia, cataleptic-like effects, and analgesia. The present studies demonstrate that doses of CB agonists that produce these effects also reliably increase diuresis. Diuretic effects of several CB agonists were measured in female rats over 2hrs immediately after drug injection and results were compared to hypothermic effects. Direct-acting CB1 agonists, including Δ(9)-THC, WIN 55,212, AM2389, and AM4054 produced dose-dependent increases in diuresis and decreases in colonic temperature with slightly lower ED50 values for diuresis than for hypothermia. The highest doses of cannabinoid drugs yielded, on average, 26 to 32 g/kg urine; comparable effects were obtained with 10 mg/kg furosemide and 3.0 mg/kg U50 488. Methanandamide, 10.0 mg/kg, had lesser effect than other CB agonists, and the CB2 agonist AM1241, the anandamide transport inhibitor AM404, and the CB antagonist rimonabant did not have diuretic effects. In further studies, the diuretic effects of the CB1 agonist AM4054 were similar in male and female rats, displayed a relatively rapid onset to action, and were dose-dependently antagonized by 30 min pretreatment with rimonabant, but not by the TRPV1 antagonist capsazepine, nor were the effects of WIN 55,212 antagonized by the CB2 antagonist AM630. These data indicate that cannabinoids have robust diuretic effects in rats that are mediated via CB1 receptor mechanisms.Journal of Pharmacology and Experimental Therapeutics 09/2012; · 3.83 Impact Factor -
Article: AM2389, a high-affinity, in vivo potent CB1-receptor-selective cannabinergic ligand as evidenced by drug discrimination in rats and hypothermia testing in mice.
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ABSTRACT: The endocannabinoid signaling system (ECS) has been targeted for developing novel therapeutics since ECS dysfunction has been implicated in various pathologies. Current focus is on chemical modifications of the hexahydrocannabinol (HHC) nabilone (Cesamet(®)). To characterize the novel, high-affinity cannabinoid receptor 1 (CB(1)R) HHC-ligand AM2389 [9β-hydroxy-3-(1-hexyl-cyclobut-1-yl)-hexahydrocannabinol in two rodent pre-clinical assays. CB(1)R mediation of AM2389-induced hypothermia in mice was evaluated with AM251, a CB(1)R-selective antagonist/inverse agonist. Additionally, two groups of rats discriminated the full cannabinergic aminoalkylindole AM5983 (0.18 and 0.56 mg/kg) from vehicle 20 min post-injection in a two-choice operant conditioning task motivated by 0.1% saccharin/water. Generalization/substitution tests were conducted with AM2389, AM5983, and Δ(9)-tetrahydrocannabinol (Δ(9)-THC). Δ(9)-THC (30 mg/kg)-induced hypothermia exhibited a faster onset and shorter duration of action compared with AM2389 (0.1 and 0.3 mg/kg). AM251 (3 and 10 mg/kg) attenuated/blocked hypothermia induced by 0.3 mg/kg AM2389. In drug discrimination, the order of potency was AM2389 > AM5983 > Δ(9)-THC with ED(50) values of 0.0025, 0.0571, and 0.2635 mg/kg, respectively, in the low-dose condition. The corresponding ED(50) values in the high-dose condition were 0.0069, 0.1246, and 0.8438 mg/kg, respectively. Onset of the effects of AM2389 was slow with a protracted time-course; the functional, perceptual in vivo half-life was approximately 17 h. This potent cannabinergic HHC exhibited a slow onset of action with a protracted time-course. The AM2389 chemotype appears well suited for further drug development, and AM2389 currently is used to probe behavioral consequences of sustained ECS activation.Psychopharmacologia 03/2012; 220(2):417-26. · 4.08 Impact Factor
