John W. Huffman

Clemson University, Anderson, Indiana, United States

Are you John W. Huffman?

Claim your profile

Publications (87)239.31 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Context: Beta-arrestins are known to couple to some G-protein-coupled receptors (GPCRs) to regulate receptor internalization, G-protein coupling and signal transduction, but have not been investigated for most receptors, and for very few receptors in vivo. Previous studies have shown that beta-arrestin2 deletion enhances the efficacy of specific cannabinoid agonists. Objective: The present study hypothesized that brain cannabinoid CB1 receptors are regulated by beta-arrestin2. Methods: Beta-arrestin2+/+ and -/- mice were used. Western blotting was used to determine the relative levels of each beta-arrestin subtype in mouse brain. Receptor binding was measured to determine whether deletion of beta-arrestin2 influences agonist binding to brain CB1 receptors, or the subcellular localization of CB1 in brain membranes subjected to differential centrifugation. A variety of cannabinoid agonists from different chemical classes were investigated for their ability to activate G-proteins in the presence and absence of beta-arrestin2 in cerebellum, hippocampus and cortex. Results: No differences were found in the density of beta-arrestin1 or cannabinoid CB1 receptors in several brains of beta-arrestin2+/+ versus -/- mice. Differences between genotypes were found in the proportion of high- and low-affinity agonist binding sites in brain areas that naturally express higher levels of beta-arrestin2. Cortex from beta-arrestin2-/- mice contained less CB1 in the P1 fraction and more CB1 in the P2 fraction compared to beta-arrestin2+/+. Of the agonists assayed for activity, only Δ(9)-tetrahydrocannabinol (THC) exhibited a difference between genotypes, in that it was less efficacious in beta-arrestin2-/- than +/+ mouse membranes. Conclusion: Beta-arrestin2 regulates cannabinoid CB1 receptors in brain.
    Journal of Receptor and Signal Transduction Research 10/2013; DOI:10.3109/10799893.2013.838787 · 1.61 Impact Factor
  • Jenny L Wiley, Julie A Marusich, John W Huffman
    [Show abstract] [Hide abstract]
    ABSTRACT: Originally synthesized for research purposes, indole- and pyrrole-derived synthetic cannabinoids are the most common psychoactive compounds contained in abused products marketed as "spice" or "herbal incense." While CB1 and CB2 receptor affinities are available for most of these research chemicals, in vivo pharmacological data are sparse. In mice, cannabinoids produce a characteristic profile of dose-dependent effects: antinociception, hypothermia, catalepsy and suppression of locomotion. In combination with receptor binding data, this tetrad battery has been useful in evaluation of the relationship between the structural features of synthetic cannabinoids and their in vivo cannabimimetic activity. Here, published tetrad studies are reviewed and additional in vivo data on synthetic cannabinoids are presented. Overall, the best predictor of likely cannabimimetic effects in the tetrad tests was good CB1 receptor affinity. Further, retention of good CB1 affinity and in vivo activity was observed across a wide array of structural manipulations of substituents of the prototypic aminoalkylindole molecule WIN55,212-2, including substitution of an alkyl for the morpholino group, replacement of an indole core with a pyrrole or phenylpyrrole, substitution of a phenylacetyl or tetramethylcyclopropyl group for JWH-018's naphthoyl, and halogenation of the naphthoyl group. This flexibility of cannabinoid ligand-receptor interactions has been a particular challenge for forensic scientists who have struggled to identify and regulate each new compound as it has appeared on the drug market. One of the most pressing future research needs is determination of the extent to which the pharmacology of these synthetic cannabinoids may differ from those of classical cannabinoids.
    Life sciences 09/2013; 97(1). DOI:10.1016/j.lfs.2013.09.011 · 2.30 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The increasing prevalence and use of herbal mixtures containing synthetic cannabinoids presents a growing public health concern and legal challenge for society. In contrast to the plant-derived cannabinoids in medical marijuana and other cannabinoid-based therapeutics, the commonly encountered synthetic cannabinoids in these mendaciously labeled products constitute a structurally diverse set of compounds of relatively unknown pharmacology and toxicology. Indeed, the use of these substances has been associated with an alarming number of hospitalizations and emergency room visits. Moreover, there are already several hundred known cannabinoid agonist compounds that could potentially be used for illicit purposes, posing an additional challenge for public health professionals and law enforcement efforts, which often require the detection and identification of the active ingredients for effective treatment or prosecution. A solid-phase microextraction headspace gas chromatography-mass spectrometry method is shown here to allow for rapid and reliable detection and structural identification of many of the synthetic cannabinoid compounds that are currently or could potentially be used in herbal smoking mixtures. This approach provides accelerated analysis and results that distinguish between structural analogs within several classes of cannabinoid compounds, including positional isomers. The analytical results confirm the continued manufacture and distribution of herbal materials with synthetic cannabinoids and provide insight into the manipulation of these products to avoid legal constraints and prosecution.
    Journal of analytical toxicology 06/2012; 36(5):293-302. DOI:10.1093/jat/bks025 · 2.63 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To develop SAR at both the cannabinoid CB(1) and CB(2) receptors for 3-(1-naphthoyl)indoles bearing moderately electron withdrawing substituents at C-4 of the naphthoyl moiety, 1-propyl and 1-pentyl-3-(4-fluoro, chloro, bromo and iodo-1-naphthoyl) derivatives were prepared. To study the steric and electronic effects of substituents at the 8-position of the naphthoyl group, the 3-(4-chloro, bromo and iodo-1-naphthoyl)indoles were also synthesized. The affinities of both groups of compounds for the CB(1) and CB(2) receptors were determined and several of them were evaluated in vivo in the mouse. The effects of these substituents on receptor affinities and in vivo activity are discussed and structure-activity relationships are presented. Although many of these compounds are selective for the CB(2) receptor, only three JWH-423, 1-propyl-3-(4-iodo-1-naphthoyl)indole, JWH-422, 2-methyl-1-propyl-3-(4-iodo-1-naphthoyl)indole, the 2-methyl analog of JWH-423 and JWH-417, 1-pentyl-3-(8-iodo-1-naphthoyl)indole, possess the desirable combination of low CB(1) affinity and good CB(2) affinity.
    Bioorganic & medicinal chemistry 03/2012; 20(6):2067-81. DOI:10.1016/j.bmc.2012.01.038 · 2.95 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Smoking of synthetic cannabinoid-enhanced "herbal incense" is an emerging substance abuse problem. The indole-derived cannabinoids identified in these products were originally developed as research tools and are structurally distinct from cannabinoids in the cannabis plant. Although abused by humans, most published research on this class of compounds has been performed in vitro. The purpose of this study was to evaluate a novel series of 1-pentyl-3-phenylacetylindoles in mice. The potencies of these analogs to produce the cannabinoid agonist effects of antinociception, hypothermia and suppression of locomotion were evaluated in ICR mice. The major structural manipulations in the present series included the type of substituent (i.e., unsubstituted, methyl, methoxy, chloro, bromo, and fluoro) and the position of the substituent on the phenyl ring (i.e., 2-, 3- or 4-position). Potencies of this series of phenylacetylindoles for each cannabinoid effect were highly correlated with CB(1) receptor affinities reported previously. Active compounds produced a profile of effects that resembled that exhibited by Δ(9)-tetrahydrocannabinol (THC). The most critical factor affecting in vivo potency was the position of the substituent. Whereas compounds with 2- and 3-phenylacetyl substituents were efficacious with good potencies, 4-substituents resulted in compounds that had poor potency or were inactive. These results suggest that phenylacetylindoles with good CB(1) binding affinity share pharmacological properties with THC in mice; however, they also emphasize the complexity of molecular interactions of synthetic cannabinoids with CB(1) receptors and suggest that scheduling efforts based solely upon structural features should proceed with caution.
    Drug and alcohol dependence 11/2011; 123(1-3):148-53. DOI:10.1016/j.drugalcdep.2011.11.001 · 3.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Gathering and communicating knowledge are important aspects of the scientific endeavor. Yet presentation of data in public forums such as scientific meetings and publications makes it available not only to scientists, but also to others who may have different ideas about how to use research findings. A recent example of this type of hijacking is the introduction of synthetic cannabinoids that are sprayed on herbal products and subsequently smoked for their marijuana-like intoxicating properties. Originally developed for the legitimate research purpose of furthering understanding of the cannabinoid system, these synthetic cannabinoids are being abused worldwide, creating issues for regulatory and law enforcement agencies that are struggling to keep up with the growing number of compounds of various structural motifs. Basic and clinical scientists need to provide advice now to facilitate decision-making about the health threats posed by this emerging problem.
  • Jianhong Chen, Valerie J. Smith, John W. Huffman
    ChemInform 02/2011; 42(7):no-no. DOI:10.1002/chin.201107122
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rimonabant, the prototypic antagonist of cannabinoid CB(1) receptors, has been reported to have inverse agonist properties at higher concentrations, which may complicate its use as a tool for mechanistic evaluation of cannabinoid pharmacology. Consequently, recent synthesis efforts have concentrated on discovery of a neutral antagonist using a variety of structural templates. The purpose of this study was to evaluate the pharmacological properties of the putative neutral cannabinoid CB(1) receptor antagonist O-2050, a sulfonamide side chain analog of Δ(8)-tetrahydrocannabinol. O-2050 and related sulfonamide cannabinoids exhibited good affinity for both cannabinoid CB(1) and CB(2) receptors. While the other sulfonamide analogs produced cannabinoid agonist effects in vivo (e.g., activity suppression, antinociception, and hypothermia), O-2050 stimulated activity and was inactive in the other two tests. O-2050 also decreased food intake in mice, an effect that was reminiscent of that produced by rimonabant. Unlike rimonabant, however, O-2050 did not block the effects of cannabinoid agonists in vivo, even when administered i.c.v. In contrast, O-2050 antagonized the in vitro effects of cannabinoid agonists in [(35)S]GTPγS and mouse vas deferens assays without having activity on its own in either assay. Further evaluation revealed that O-2050 fully and dose-dependently substituted for Δ(9)-tetrahydrocannabinol in a mouse drug discrimination procedure (a cannabinoid agonist effect) and that it inhibited forskolin-stimulated cyclic AMP signaling with a maximum efficacy of approximately half that of the full agonist CP55,940 [(-)-cis-3-[2-hydroxy-4(1,1-dimethyl-heptyl)phenyl]-trans-4-(3-hydroxy-propyl)cyclohexanol]. Together, these results suggest that O-2050 is not a viable candidate for classification as a neutral cannabinoid CB(1) receptor antagonist.
    European journal of pharmacology 01/2011; 651(1-3):96-105. DOI:10.1016/j.ejphar.2010.10.085 · 2.68 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 12/2010; 29(51). DOI:10.1002/chin.199851225
  • J. W. HUFFMAN, M.-J. WU, J. LU
    [Show abstract] [Hide abstract]
    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 11/2010; 29(47). DOI:10.1002/chin.199847130
  • Source
    Jianhong Chen, Valerie J Smith, John W Huffman
    Organic Preparations and Procedures International 10/2010; 42(5):490-493. DOI:10.1080/00304948.2010.514799 · 1.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Δ(8)-Tetrahydrocannabinol (26), 3-(1',1'-dimethylbutyl)- (12), 3-(1',1'-dimethylpentyl)- (13), 3-(1',1'-dimethylhexyl)- (14) and 3-(1',1'-dimethylheptyl)-Δ(8)-tetrahydrocannabinol (15) have been converted into the corresponding 1-bromo-1-deoxy-Δ(8)-tetrahydrocannabinols (25, 8-11). This was accomplished using a protocol developed in our laboratory in which the trifluoromethanesulfonate of a phenol undergoes palladium mediated coupling with pinacolborane. Reaction of this dioxaborolane with aqueous-methanolic copper(II) bromide provides the aryl bromide. The affinities of these bromo cannabinoids for the cannabinoid CB(1) and CB(2) receptors were determined. All of these compounds showed selectivity for the CB(2) receptor and one of them, 1-bromo-1-deoxy-3-(1',1'-dimethylhexyl)-Δ(8)-tetrahydrocannabinol (10), exhibits 52-fold selectivity for this receptor with good (28nM) affinity.
    Bioorganic & medicinal chemistry 09/2010; 18(22):7809-15. DOI:10.1016/j.bmc.2010.09.061 · 2.95 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Three 1-methoxy analogs of CP-47,497 (7, 8, and 19) have been synthesized and their affinities for the cannabinoid CB1 and CB2 receptors have been determined. Although these compounds exhibit selectivity for the CB2 receptor none have significant affinity for either receptor. Modeling and receptor docking studies were carried out, which provide a rationalization for the weak affinities of these compounds for either receptor.
    Bioorganic & medicinal chemistry 08/2010; 18(15):5475-5482. DOI:10.1016/j.bmc.2010.06.054 · 2.95 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A completely regioselective synthesis of (±)-11-nor-9-carboxy-Δ9-tetrahydrocannabmol (1), a principal human metabolite of Δ9-tetrahydrocannabinol (2), has been carried out in seven steps and 14% overall yield from apoverbenone (9) and the bis-MOM ether of olivetol. Condensation of 9 with the arylhthium derived from the bis-MOM ether of olivetol gives an unstable tertiary allylic alcohol that undergoes oxidative rearrangement to give enone 42. Reaction of 42 with acid results in hydrolysis of the MOM ethers and cyclization to benzopyranone 21. Conversion to MOM ether 39 followed by Li/NH3 reduction and trapping of the enolate with N-phenyltriflimide gives vinyl triflate 40 plus the isomer with a cis ring fusion. Palladium-catalyzed carboxylation, hydrolysis of the MOM ether, and separation from cis acid 41 gives pure 1. Model experiments employing unsubsututed resorcinol derivatives that lead to ester 27 are described, as are a number of alternative approaches to acid 1.
    ChemInform 07/2010; 22(29):170-170. DOI:10.1002/chin.199129170
  • [Show abstract] [Hide abstract]
    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 07/2010; 26(29). DOI:10.1002/chin.199529326
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 'Spice' is an herbal blend primarily marketed in Europe as a mild hallucinogen with prominent cannabis-like effects and as a legal alternative to cannabis. However, a recent report identified a number of synthetic additives in samples of 'Spice'. One of these, the indole derivative JWH018, is a ligand for the cannabinoid receptor 1 (CB(1)) cannabinoid receptor and inhibits cAMP production in CB(1) receptor-expressing CHO cells. Other effects of JWH018 on CB(1) receptor-mediated signalling are not known, particularly in neurons. Here we have evaluated the signalling pathways activated by JWH018 at CB(1) receptors. We investigated the effects of JWH018 on neurotransmission in cultured autaptic hippocampal neurons. We further analysed its activation of ERK1/2 mitogen activated protein kinase (MAPK) and internalization of CB(1) receptors in HEK293 cells stably expressing this receptor. In cultured autaptic hippocampal neurons, JWH018 potently inhibited excitatory postsynaptic currents (IC(50)= 14.9 nM) in a concentration- and CB(1) receptor-dependent manner. Furthermore, it increased ERK1/2 MAPK phosphorylation (EC(50)= 4.4 nM). We also found that JWH018 potently induced rapid and robust CB(1) receptor internalization (EC(50)= 2.8 nM; t(1/2)= 17.3 min). JWH018, a prominent component of several herbal preparations marketed for their psychoactivity, is a potent and effective CB(1) receptor agonist that activates multiple CB(1) receptor signalling pathways. Thus, it is likely that the subjective effects of 'Spice' are due to activation of cannabinoid CB(1) receptors by JWH018, added to this herbal preparation.
    British Journal of Pharmacology 06/2010; 160(3):585-93. DOI:10.1111/j.1476-5381.2009.00582.x · 4.99 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 05/2010; 28(20). DOI:10.1002/chin.199720126
  • [Show abstract] [Hide abstract]
    ABSTRACT: The four diastereomers of 1′,2′-dimethylheptyl-Δ8-THC (2) have been synthesized. Pharmacology both in vitro and in vivo indicated that all four isomers were very potent cannabinoids. The 1′R,2′S and 1′S,2′R are considerably more potent than the other two isomers, and are among the most potent traditional cannabinoids known.
    ChemInform 02/2010; 29(8). DOI:10.1002/chin.199808232
  • J. W. HUFFMAN, M.‐J. WU, W. K. BANNER, D. DAI
    [Show abstract] [Hide abstract]
    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 02/2010; 29(5). DOI:10.1002/chin.199805239
  • [Show abstract] [Hide abstract]
    ABSTRACT: The reaction of 2-aminocyclohex-2-en-1-ones with cyclic nitroolefins has been investigated as a possible synthetic route to polyquinanes. Figure optionsView in workspace
    ChemInform 01/2010; 24(1):149-149. DOI:10.1002/chin.199301149

Publication Stats

3k Citations
239.31 Total Impact Points

Institutions

  • 1987–2013
    • Clemson University
      • Department of Chemistry
      Anderson, Indiana, United States
  • 2003
    • Centro Investigaciones Energéticas, Medioambientales y Tecnológicas
      Madrid, Madrid, Spain
  • 2001
    • Complutense University of Madrid
      • Departamento de Bioquímica y Biología Molecular I
      Madrid, Madrid, Spain
  • 1998
    • Virginia Commonwealth University
      • Department of Pharmacology and Toxicology
      Richmond, VA, United States