Publications (8) View all
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Article: Sulfonyl Fluoride Inhibitors of Fatty Acid Amide Hydrolase.
Shakiru O Alapafuja, Spyros P Nikas, Indu Bharatan, Vidyanand G Shukla, Mahmoud L Nasr, Anna L Bowman, Nikolai Zvonok, Jing Li, Xiaomeng Shi, John R Engen, Alexandros Makriyannis[show abstract] [hide abstract]
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: A new generation fatty acid amide hydrolase inhibitor protects against kainate-induced excitotoxicity.
Vinogran Naidoo, Spyros P Nikas, David A Karanian, Jeannie Hwang, Jianhong Zhao, JodiAnne T Wood, Shakiru O Alapafuja, Subramanian K Vadivel, David Butler, Alexandros Makriyannis, Ben A Bahr[show abstract] [hide abstract]
ABSTRACT: Endocannabinoids, including anandamide (AEA), have been implicated in neuroprotective on-demand responses. Related to such a response to injury, an excitotoxic kainic acid (KA) injection (i.p.) was found to increase AEA levels in the brain. To modulate the endocannabinoid response during events of excitotoxicity in vitro and in vivo, we utilized a new generation compound (AM5206) that selectively inhibits the AEA deactivating enzyme fatty acid amide hydrolase (FAAH). KA caused calpain-mediated spectrin breakdown, declines in synaptic markers, and disruption of neuronal integrity in cultured hippocampal slices. FAAH inhibition with AM5206 protected against the neurodegenerative cascade assessed in the slice model 24 h postinsult. In vivo, KA administration induced seizures and the same neurodegenerative events exhibited in vitro. When AM5206 was injected immediately after KA in rats, the seizure scores were markedly reduced as were levels of cytoskeletal damage and synaptic protein decline. The pre- and postsynaptic proteins were protected by the FAAH inhibitor to levels comparable to those found in healthy control brains. These data support the idea that endocannabinoids are released and converge on pro-survival pathways that prevent excitotoxic progression.Journal of Molecular Neuroscience 11/2010; 43(3):493-502. · 2.50 Impact Factor -
Article: Inhibitor of fatty acid amide hydrolase normalizes cardiovascular function in hypertension without adverse metabolic effects.
Grzegorz Godlewski, Shakiru O Alapafuja, Sándor Bátkai, Spyros P Nikas, Resat Cinar, László Offertáler, Douglas Osei-Hyiaman, Jie Liu, Bani Mukhopadhyay, Judith Harvey-White, Joseph Tam, Karel Pacak, Jacqueline L Blankman, Benjamin F Cravatt, Alexandros Makriyannis, George Kunos[show abstract] [hide abstract]
ABSTRACT: The enzyme fatty acid amide hydrolase (FAAH) catalyzes the in vivo degradation of the endocannabinoid anandamide, thus controlling its action at receptors. A novel FAAH inhibitor, AM3506, normalizes the elevated blood pressure and cardiac contractility of spontaneously hypertensive rats (SHR) without affecting these parameters in normotensive rats. These effects are due to blockade of FAAH and a corresponding rise in brain anandamide levels, resulting in CB₁ receptor-mediated decrease in sympathetic tone. The supersensitivity of SHR to CB₁ receptor-mediated cardiovascular depression is related to increased G protein coupling of CB₁ receptors. Importantly, AM3506 does not elicit hyperglycemia and insulin resistance seen with other FAAH inhibitors or in FAAH⁻/⁻ mice, which is related to its inability to inhibit FAAH in the liver due to rapid hepatic uptake and metabolism. This unique activity profile offers improved therapeutic value in hypertension.Chemistry & biology 11/2010; 17(11):1256-66. · 6.52 Impact Factor -
Article: Novel 1',1'-chain substituted hexahydrocannabinols: 9β-hydroxy-3-(1-hexyl-cyclobut-1-yl)-hexahydrocannabinol (AM2389) a highly potent cannabinoid receptor 1 (CB1) agonist.
Spyros P Nikas, Shakiru O Alapafuja, Ioannis Papanastasiou, Carol A Paronis, Vidyanand G Shukla, Demetris P Papahatjis, Anna L Bowman, Aneetha Halikhedkar, Xiuwen Han, Alexandros Makriyannis[show abstract] [hide abstract]
ABSTRACT: In pursuit of a more detailed understanding of the structural requirements for the key side chain cannabinoid pharmacophore, we have extended our SAR to cover a variety of conformationally modified side chains within the 9-keto and 9-hydroxyl tricyclic structures. Of the compounds described here, those with a seven-atom long side chain substituted with a cyclopentyl ring at C1' position have very high affinities for both CB1 and CB2 (0.97 nM < K(i) < 5.25 nM), with no preference for either of the two receptors. However, presence of the smaller cyclobutyl group at the C1' position leads to an optimal affinity and selectivity interaction with CB1. Thus, two of the C1'-cyclobutyl analogues, namely, (6aR,10aR)-3-(1-hexyl-cyclobut-1-yl)-6,6a,7,8,10,10a-hexahydro-1-hydroxy-6,6-dimethyl-9H-dibenzo[b,d]pyran-9-one and (6aR,9R,10aR)-3-(1-hexyl-cyclobut-1-yl)-6a,7,8,9,10,10a-hexahydro-6,6-dimethyl-6H-dibenzo[b,d]pyran-1,9 diol (7e-β, AM2389), exhibited remarkably high affinities (0.84 and 0.16 nM, respectively) and significant selectivities (16- and 26-fold, respectively) for CB1. Compound 7e-β was found to exhibit exceptionally high in vitro and in vivo potency with a relatively long duration of action.Journal of Medicinal Chemistry 10/2010; 53(19):6996-7010. · 4.80 Impact Factor -
Article: Microwave Assisted Synthesis of Sodium Sulfonates Precursors of Sulfonyl Chlorides and Fluorides.
Shakiru O Alapafuja, Spyros P Nikas, Vidyanand G Shukla, Ioannis Papanastasiou, Alexandros Makriyannis[show abstract] [hide abstract]
ABSTRACT: We describe the use of a microwave reaction for the conversion of various bromides to sodium sulfonates that have been further elaborated to sulfonyl chlorides. This new approach leads to much improved yields and shorter reaction times. Representative sulfonyl chlorides serve as precursors for the respective sulfonyl fluorides that are potent inhibitors of the fatty acid amide hydrolase.Tetrahedron Letters 12/2009; 50(50):7028-7031. · 2.68 Impact Factor