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S. Wayne Mascarella

Bio: S. Wayne Mascarella is an academic researcher from Research Triangle Park. The author has contributed to research in topics: Opioid receptor & Agonist. The author has an hindex of 22, co-authored 76 publications receiving 1996 citations. Previous affiliations of S. Wayne Mascarella include University of New Orleans & University of North Carolina at Chapel Hill.


Papers
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Journal ArticleDOI
17 May 2012-Nature
TL;DR: Analysis of site-directed mutagenesis and ligand structure–activity relationships confirms the interactions observed in the crystal structure, thereby providing a molecular explanation for κ-OR subtype selectivity, and essential insights for the design of compounds with new pharmacological properties targeting the human λ-OR.
Abstract: Here we report the crystal structure of the humank-OR in complex with the selective antagonist JDTic, arranged in parallel dimers, at 2.9 Aresolution. The structure reveals important features of the ligand-binding pocket that contribute to the high affinity and subtype selectivity of JDTic for the human k-OR. Modelling of other important k-OR-selective ligands, including the morphinan-derived antagonists norbinaltorphimine and 59-guanidinonaltrindole, and the diterpene agonist salvinorin A analogue RB-64, reveals both common and distinct features for binding these diverse chemotypes. Analysis of site-directed mutagenesis and ligand structure-activity relationships confirms the interactions observed in the crystal structure, thereby providing a molecular explanation for k-OR subtype selectivity, and essential insights for the design of compounds with new pharmacological properties targeting the human k-OR.

785 citations

Journal ArticleDOI
TL;DR: This review describes how clandestine chemists used the principles of medicinal chemistry to design molecules that elicit the effects of opioids, amphetamine and analogs, cannabinoids, and phencyclidine analogs while circumventing the law.
Abstract: There are numerous medicinal chemistry reports in the literature describing the pharmacological properties of thousands of narcotics, stimulants, hallucinogens, sedative-hypnotic drugs, cannabinoids, and other psychoactive substances as well as synthetic methods for their preparations. This information, while essential for the advancement of science, has been used by clandestine chemists to manufacture and market an endless variety of analogs of so-called designer drugs. In this review, we describe how clandestine chemists used the principles of medicinal chemistry to design molecules, referred to as designer drugs, that elicit the effects of opioids, amphetamine and analogs, cannabinoids, and phencyclidine analogs while circumventing the law.

132 citations

Journal ArticleDOI
TL;DR: It is suggested that sigma 2 receptors mediate the motor effects of sigma ligands in rats following intranigral microinjections.

80 citations

Book ChapterDOI
TL;DR: Bupropion, introduced as an antidepressant in the 1980s, is also effective as a smoking cessation aid and is beneficial in the treatment of methamphetamine addiction, cocaine dependence, addictive behaviors such as pathological gambling, and attention deficit hyperactivity disorder.
Abstract: Bupropion, introduced as an antidepressant in the 1980s, is also effective as a smoking cessation aid and is beneficial in the treatment of methamphetamine addiction, cocaine dependence, addictive behaviors such as pathological gambling, and attention deficit hyperactivity disorder. (2S,3S)-hydroxybupropion is an active metabolite of bupropion produced in humans that contributes to antidepressant and smoking cessation efficacy and perhaps benefits in other CNS disorders. Mechanisms underlying its antidepressant and smoking abstinence remain elusive. However, it seems likely that efficacy is due to a combination of the effects of bupropion and/or its active metabolite (2S,3S)-hydroxybupropion involving the inhibition of reuptake of dopamine (DA) and NE in reward centers of the brain and the noncompetitive antagonism of α4β2- and α3β4*-nAChRs. These combined effects of bupropion and its active metabolite may be responsible for its ability to decrease nicotine reward and withdrawal. Studies directed toward development of a bupropion analog for treatment of cocaine addiction led to compounds, typified by 2-(N-cyclopropylamino)-3'-chloropropiophenone (RTI-6037-39), thought to act as indirect DA agonists. In addition, (2S,3S)-hydroxybupropion analogs were developed, which had varying degrees of DA and NE uptake inhibition and antagonism of nAChRs. These compounds will be valuable tools for animal behavioral studies and as clinical candidates. Here, we review the (1) early studies leading to the development of bupropion, (2) bupropion metabolism and the identification of (2S,3R)-hydroxybupropion as an active metabolite, (3) mechanisms of bupropion and metabolite action, (4) effects in animal behavioral studies, (5) results of clinical studies, and (6) development of bupropion analogs as potential pharmacotherapies for treating nicotine and cocaine addiction.

65 citations

Journal ArticleDOI
TL;DR: So-called "bath salts" largely contain synthetic analogs of the natural compound Khat; spice-related materials, claimed to be "legal marijuana," are mostly synthetic Analogs of cannabinoid receptor ligands that were developed as research tools.

64 citations


Cited by
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Journal ArticleDOI
14 Feb 2013-Nature
TL;DR: Through a systematic analysis of high-resolution GPCR structures, a conserved network of non-covalent contacts that defines the G PCR fold is uncovered and characteristic features of ligand binding and conformational changes during receptor activation are revealed.
Abstract: G-protein-coupled receptors (GPCRs) are physiologically important membrane proteins that sense signalling molecules such as hormones and neurotransmitters, and are the targets of several prescribed drugs. Recent exciting developments are providing unprecedented insights into the structure and function of several medically important GPCRs. Here, through a systematic analysis of high-resolution GPCR structures, we uncover a conserved network of non-covalent contacts that defines the GPCR fold. Furthermore, our comparative analysis reveals characteristic features of ligand binding and conformational changes during receptor activation. A holistic understanding that integrates molecular and systems biology of GPCRs holds promise for new therapeutics and personalized medicine.

1,296 citations

Journal ArticleDOI
01 Jun 2002-Proteins
TL;DR: The docking field has come of age, and the time is ripe to present the principles of docking, reviewing the current state of the field from both the computational and the biological points of view.
Abstract: The docking field has come of age. The time is ripe to present the principles of docking, reviewing the current state of the field. Two reasons are largely responsible for the maturity of the computational docking area. First, the early optimism that the very presence of the "correct" native conformation within the list of predicted docked conformations signals a near solution to the docking problem, has been replaced by the stark realization of the extreme difficulty of the next scoring/ranking step. Second, in the last couple of years more realistic approaches to handling molecular flexibility in docking schemes have emerged. As in folding, these derive from concepts abstracted from statistical mechanics, namely, populations. Docking and folding are interrelated. From the purely physical standpoint, binding and folding are analogous processes, with similar underlying principles. Computationally, the tools developed for docking will be tremendously useful for folding. For large, multidomain proteins, domain docking is probably the only rational way, mimicking the hierarchical nature of protein folding. The complexity of the problem is huge. Here we divide the computational docking problem into its two separate components. As in folding, solving the docking problem involves efficient search (and matching) algorithms, which cover the relevant conformational space, and selective scoring functions, which are both efficient and effectively discriminate between native and non-native solutions. It is universally recognized that docking of drugs is immensely important. However, protein-protein docking is equally so, relating to recognition, cellular pathways, and macromolecular assemblies. Proteins function when they are bound to other molecules. Consequently, we present the review from both the computational and the biological points of view. Although large, it covers only partially the extensive body of literature, relating to small (drug) and to large protein-protein molecule docking, to rigid and to flexible. Unfortunately, when reviewing these, a major difficulty in assessing the results is the non-uniformity in the formats in which they are presented in the literature. Consequently, we further propose a way to rectify it here.

1,251 citations

Journal ArticleDOI
TL;DR: New features in the fifth major GPCRdb release are highlighted, including G PCR crystal structure browsing, superposition and display of ligand interactions, direct deposition by users of point mutations and their effects on ligand binding.
Abstract: Recent developments in G protein-coupled receptor (GPCR) structural biology and pharmacology have greatly enhanced our knowledge of receptor structure-function relations, and have helped improve the scientific foundation for drug design studies. The GPCR database, GPCRdb, serves a dual role in disseminating and enabling new scientific developments by providing reference data, analysis tools and interactive diagrams. This paper highlights new features in the fifth major GPCRdb release: (i) GPCR crystal structure browsing, superposition and display of ligand interactions; (ii) direct deposition by users of point mutations and their effects on ligand binding; (iii) refined snake and helix box residue diagram looks; and (iii) phylogenetic trees with receptor classification colour schemes. Under the hood, the entire GPCRdb front- and back-ends have been re-coded within one infrastructure, ensuring a smooth browsing experience and development. GPCRdb is available at http://www.gpcrdb.org/ and it's open source code at https://bitbucket.org/gpcr/protwis.

993 citations

Journal ArticleDOI
TL;DR: The final recommendations recognize that obesity is a complex, adiposity-based chronic disease, where management targets both weight-related complications and adiposity to improve overall health and quality of life.

978 citations

Journal ArticleDOI
TL;DR: High-resolution crystallography of G protein-coupled receptors shows the receptors as allosteric machines that are controlled not only by ligands but also by ions, lipids, cholesterol, and water, and helps redefine knowledge of how GPCRs recognize such a diverse array of ligands.
Abstract: During the past few years, crystallography of G protein–coupled receptors (GPCRs) has experienced exponential growth, resulting in the determination of the structures of 16 distinct receptors—9 of them in 2012 alone. Including closely related subtype homology models, this coverage amounts to approximately 12% of the human GPCR superfamily. The adrenergic, rhodopsin, and adenosine receptor systems are also described by agonist-bound active-state structures, including a structure of the receptor–G protein complex for the β2-adrenergic receptor. Biochemical and biophysical techniques, such as nuclear magnetic resonance and hydrogen-deuterium exchange coupled with mass spectrometry, are providing complementary insights into ligand-dependent dynamic equilibrium between different functional states. Additional details revealed by high-resolution structures illustrate the receptors as allosteric machines that are controlled not only by ligands but also by ions, lipids, cholesterol, and water. This wealth of data ...

939 citations