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Carrie Haskell-luevano - One of the best experts on this subject based on the ideXlab platform.
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An in Vitro and in Vivo Investigation of Bivalent Ligands That Display Preferential Binding and Functional Activity for Different Melanocortin Receptor Homodimers.
Journal of medicinal chemistry, 2016Co-Authors: Cody J. Lensing, Katie T. Freeman, Sathya M. Schnell, Danielle N. Adank, Robert C. Speth, Carrie Haskell-luevanoAbstract:Pharmacological probes for the Melanocortin Receptors have been utilized for studying various disease states including cancer, sexual function disorders, Alzheimer’s disease, social disorders, cachexia, and obesity. This study focused on the design and synthesis of bivalent ligands to target Melanocortin Receptor homodimers. Lead ligands increased binding affinity by 14- to 25-fold and increased cAMP signaling potency by 3- to 5-fold compared to their monovalent counterparts. Unexpectedly, different bivalent ligands showed preferences for particular Melanocortin Receptor subtypes depending on the linker that connected the binding scaffolds, suggesting structural differences between the various dimer subtypes. Homobivalent compound 12 possessed a functional profile that was unique from its monovalent counterpart providing evidence of the discrete effects of bivalent ligands. Lead compound 7 significantly decreased feeding in mice after intracerebroventricular administration. To the best of our knowledge, t...
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The 1,4-benzodiazepine-2,5-dione small molecule template results in Melanocortin Receptor agonists with nanomolar potencies.
Journal of medicinal chemistry, 2008Co-Authors: Christine G. Joseph, Krista R. Wilson, Michael S. Wood, Nicholas B. Sorenson, Dong V. Phan, Zhimin Xiang, Rachel M. Witek, Carrie Haskell-luevanoAbstract:The Melanocortin system consists of five seven-transmembrane spanning G-protein coupled Receptors (MC1-5) that are stimulated by endogenous agonists and antagonized by the only two known endogenous antagonists of GPCRs, agouti and agouti-related protein (AGRP). These Receptors have been associated with many physiological functions, including the involvement of the MC4R in feeding behavior and energy homeostasis, making this system an attractive target for the treatment of obesity. Small-molecule mimetics of endogenous ligands may result in the development of compounds with properties more suitable for use as therapeutic agents. The research presented herein involves the synthesis and analysis of 12 Melanocortin Receptor agonists using the 1,4-benzodiazepine-2,5-dione template and is the first report of these derivatives as Melanocortin Receptor agonists. Structure-activity relationship studies using this privileged structure template has resulted in molecules with molecular weights around 400 that possess nanomolar agonist potency at the Melanocortin Receptors examined in this study.
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A review of Melanocortin Receptor small molecule ligands
Peptides, 2005Co-Authors: Aleksandar Todorovic, Carrie Haskell-luevanoAbstract:Abstract The Melanocortin system (MC) is implicated in the regulation of a variety of physiological pathways including pigmentation, steroid function, energy homeostasis, food intake, obesity, cardiovascular, sexual function, and normal gland regulation. The Melanocortin system consists of five Receptors identified to date (MC1–5R), Melanocortin agonists derived from the pro-opioMelanocortin prohormone (POMC) and two naturally existing antagonists. Melanocortin Receptor ligand structure–activity studies have been performed since the 1960s, primarily focused on the pigmentation aspect of physiology. During the 1990s, the Melanocortin-4 Receptor was identified to play a significant physiological role in the regulation of both food intake and obesity. Subsequently, a concerted drug design effort has focused on the design and discovery of Melanocortin Receptor small molecules. Herein, we present an overview of Melanocortin Receptor heterocyclic small molecules.
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In Vitro Mutagenesis Studies of Melanocortin Receptor Coupling and Ligand Binding
The Melanocortin Receptors, 2000Co-Authors: Carrie Haskell-luevanoAbstract:The melanocyte stimulating hormone Receptor (MSH-R); Melanocortin 1 Receptor (MC1-R) and the adrenocorticotropin hormone (ACTH) Receptor (MC2-R) were the first Melanocortin Receptors cloned and characterized (1,2). Subsequently, three other Melanocortin Receptor subtypes have been cloned and designated the MC3-R, MC4-R, and MC5-R. The MC1-R has been clearly demonstrated to be involved in pigmentation and animal coat coloration (3,4). The efficacy of Melanocortin peptides at the MC1-R can be summarized as 4-norleucine, 7-d-phenylalanine (NDP-MSH) > α-MSH > ACTH >γ-MSH. With the availability of the cloned Melanocortin Receptors, several questions can now be studied. In vitro investigations using these cloned Receptors may include identifying critical ligand features resulting in Receptor selectivity, ligand residues responsible for differing efficacies, and how these ligand residues interact with the Receptor for recognition and activation. In lieu of X-ray crystal structures, three-dimensional (3D) homology Receptor modeling has become a tool to attempt to identify noteworthy ligand and Receptor features. Furthermore, knowledge of the molecular mechanism responsible for the initial intracellular signal transduction cascade would be potentially important for the design of antagonists. This chapter is designed to attempt to address these issues from the available literature.
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Three-dimensional molecular models of the hMC1R Melanocortin Receptor: complexes with melanotropin peptide agonists.
Drug Design and Discovery, 1996Co-Authors: Carrie Haskell-luevano, Ira Gantz, Tomi K. Sawyer, Susanne Trumpp-kallmeyer, Jack A. Bikker, Christine Humblet, Victor J. HrubyAbstract:Three-dimensional molecular models of the human Melanocortin Receptor (hMCIR) have been developed based upon the electron cryo-microscopic structure of bacteriorhodopsin and the electron density footprint of bovine rhodopsin. a-Melanocyte-stimulating hormone, Ac-Ser-Tyr-Ser-Met 4 -Glu-His-Phe 7 -Arg-Trp-Gly-Lys-Pro-Val-NH 2 (α-MSH, α-melanotropin), and the superpotent, prolonged acting agonists, Ac-Ser-Tyr-Ser-Nle 4 -Glu-His-DPhe 7 -Arg-Trp-Gly-Lys-Pro-Val-NH 2 (NDP-MSH) and Ac-Nle 4 -c[Asp 5 -His 6 - 6-DPhe 7 -Arg 8 -Trp 9 -Lys l0 ]-NH 2 (MTII), have been modeled into the proposed binding sites with specific ligand-Receptor interactions identified. The melanotropin sidechain pharmacophores, DPhe 7 and Trp 9 , are proposed to interact with a hydrophobic network of Receptor aromatic residues in transmembrane regions 4, 5, 6, and 7. In addition, a hydrophilic network involving the ligand Arg 8 and polar Receptor residues located in transmembrane regions 2 and 3 were identified. Biological studies on α-MSH, NDP-MSH, MTII, and related peptides have been correlated with the proposed hMC1R model in terms of agonism, affinity, and prolongation. Finally, limited MC1R mutagenesis studies comparing α-MSH and NDP-MSH are interpreted within the context of the proposed hMC1R models.
Jarl E. S. Wikberg - One of the best experts on this subject based on the ideXlab platform.
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adalimumab humira r normalizes Melanocortin Receptor subtype 2 3 and 4 expression in cd8 cd14 and cd19 leucocyte subsets in rheumatoid arthritis
Scandinavian Journal of Rheumatology, 2014Co-Authors: Marlene Andersen, Jarl E. S. Wikberg, Michael Kruse Olesen, Ivan Nagaev, Olga Nagaeva, Lucia Minchevanilsson, Grethe AndersenAbstract:Adalimumab (Humira (R)) normalizes Melanocortin Receptor subtype 2, 3, and 4 expression in CD8+, CD14+, and CD19+leucocyte subsets in rheumatoid arthritis
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Functional Evaluation of THIQ, a Melanocortin 4 Receptor Agonist, in Models of Food Intake and Inflammation
Basic & Clinical Pharmacology & Toxicology, 2007Co-Authors: Ruta Muceniece, Larisa Baumane, Ivars Kalvinsh, Jarl E. S. Wikberg, Edgars Liepinsh, Liga Zvejniece, Reinis Vilskersts, Maija DambrovaAbstract:Abstract: The central Melanocortinergic system plays an important role in regulating different aspects of energy homeostasis and the immunomodulatory response. In the present study, we evaluated the in vivo activities of food intake suppression and anti-inflammatory activity of THIQ, which has been proposed to possess high and selective Melanocortin-4 Receptor agonistic activity in vitro. The results showed that THIQ (0.1, 0.3 and 1 nmol/rat, intracerebroventricularly) is less effective in reducing food intake and body weights of rats than the non-selective Melanocortin Receptor agonist melanotan II. Electron paramagnetic resonance measurements in mice brain tissue showed that THIQ at doses of 0.001 and 0.01 nmol/mouse (intracisternally) increased the concentration of nitric oxide, which is not typical for Melanocortin Receptor agonists. In an experimental brain inflammation model, THIQ only weakly antagonized lipopolysaccharide-induced nitric oxide overproduction in brain tissue at a dose of 0.01 nmol/mouse. Our findings provide new insight into the in vivo pharmacological profile of the in vitro selective Melanocortin-4 Receptor agonist THIQ and give grounds for caution when interpreting and predicting Melanocortin Receptor selective agonist activity in vivo.
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Co-operative regulation of ligand binding to Melanocortin Receptor subtypes: evidence for interacting binding sites.
European journal of pharmacology, 2005Co-Authors: Sergei Kopanchuk, Michael Szardenings, Santa Veiksina, Ramona Petrovska, Ilze Mutule, Ago Rinken, Jarl E. S. WikbergAbstract:This study evaluates the binding the melanocyte stimulating hormone peptide analogue [125I]NDP-MSH to Melanocortin Receptors MC1, MC3, MC4 and MC5 in insect cell membranes produced by baculovirus expression systems. The presence of Ca2+ was found to be mandatory to achieve specific [125I]NDP-MSH binding to the Melanocortin Receptors. Although association kinetics of [125I]NDP-MSH followed the regularities of simple bimolecular reactions, the dissociation of [125I]NDP-MSH from the Melanocortin Receptors was heterogeneous. Eleven linear and cyclic MSH peptides studied displaced the [125I]NDP-MSH binding to the studied Melanocortin Receptors, with the shapes of their competition curves varying from biphasic or shallow to super-steep (Hill coefficients ranging from 0.4 to 1.5). Notably the same peptide often gave highly different patterns on different Melanocortin Receptor subtypes; e.g. the MC4 Receptor selective antagonist HS131 gave a Hill coefficient of 1.5 on the MC1 Receptor but 0.5-0.7 on the MC(3-5) Receptors. Adding a mask of one of the peptides to block its high affinity binding did not prevent other competing peptides to yield biphasic competition curves. The data indicate that the binding of MSH peptides to Melanocortin Receptors are governed by a complex dynamic homotropic co-operative regulations.
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quantitative measurement of the levels of Melanocortin Receptor subtype 1 2 3 and 5 and pro opio Melanocortin peptide gene expression in subsets of human peripheral blood leucocytes
Scandinavian Journal of Immunology, 2005Co-Authors: Grethe Andersen, Olga Nagaeva, Lucia Minchevanilsson, M Hagglund, Lars Frangsmyr, R Petrovska, Jarl E. S. WikbergAbstract:Levels of the Melanocortin Receptor (MCR) 1, 2, 3 and 5 subtypes and pro-opio-Melanocortin (POMC) protein mRNA were measured by the real-time quantitative reverse transcriptase polymerase chain reaction method in CD4+ T helper (Th) cells, CD8+ T cytotoxic cells, CD19+ B cells, CD56+ natural killer (NK) cells, CD14+ monocytes and CD15+ granulocytes from healthy donors. We found high levels of all of the MC1, 2, 3 and 5R subtype mRNA in Th cells and moderate levels in NK cells, monocytes and granulocytes. POMC peptide mRNA was found in all examined leucocyte subsets, but only low levels were present in granulocytes. Our findings suggest a co-ordinating role for MCR subtypes and their naturally occurring ligands in the co-operation between innate and adaptive immunity. Moreover, our findings are compatible with earlier finding of MCR-mediated tolerance induction in Th cells.
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Chronic infusion of a Melanocortin Receptor agonist modulates dopamine Receptor binding in the rat brain.
Pharmacological research, 2002Co-Authors: Jonas Lindblom, Ants Kask, Erik Hägg, Linda Härmark, Lena Bergström, Jarl E. S. WikbergAbstract:Chronic infusion of a Melanocortin Receptor agonist modulates dopamine Receptor binding in the rat brain
Rosario Martin - One of the best experts on this subject based on the ideXlab platform.
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differentiation of european wild boar sus scrofa scrofa and domestic swine sus scrofa domestica meats by pcr analysis targeting the mitochondrial d loop and the nuclear Melanocortin Receptor 1 mc1r genes
Meat Science, 2008Co-Authors: Violeta Fajardo, Mari A Rojas, Teresa Garci A, Irene Martinez Martin, Pablo E Hernandez, Isabel Gonzalez, Rosario MartinAbstract:Abstract This work describes the differentiation of European wild boar ( Sus scrofa scrofa ) and domestic swine ( Sus scrofa domestica ) meats by PCR targeting sequences from two molecular markers: the mitochondrial displacement loop (D-loop) region and the nuclear Melanocortin Receptor 1 ( MC1R ) gene. A polymorphic D-loop fragment (∼270 bp) was amplified and sequenced in a number of wild and domestic Sus scrofa meat samples, to find a nucleotide region suitable for PCR–RFLP analysis. Sequence data showed the presence of only a few point mutations across Sus scrofa D-loop sequences, not allowing direct discrimination between wild boar and domestic swine meats. Later, the MC1R gene was targeted and Sus scrofa -specific primers designed to amplify a 795 bp MC1R fragment. Subsequent RFLP analysis of the MC1R swine-specific amplicons allowed selection of BspHI and BstUI endonucleases to carry out intraspecific Sus scrofa differentiation. Digestion of MC1R amplicons with the chosen enzymes generated characteristic PCR–RFLP profiles that allowed discrimination among meats from wild and domestic swine specimens. The technique also enabled the detection of samples that yielded heterozygous profiles, suggesting hybrids resulting from wild boar and domestic pig breeding. The PCR–RFLP reported here, targeting the MC1R gene may be routinely applied to verify the correct labelling of game products.
Christine G. Joseph - One of the best experts on this subject based on the ideXlab platform.
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The 1,4-benzodiazepine-2,5-dione small molecule template results in Melanocortin Receptor agonists with nanomolar potencies.
Journal of medicinal chemistry, 2008Co-Authors: Christine G. Joseph, Krista R. Wilson, Michael S. Wood, Nicholas B. Sorenson, Dong V. Phan, Zhimin Xiang, Rachel M. Witek, Carrie Haskell-luevanoAbstract:The Melanocortin system consists of five seven-transmembrane spanning G-protein coupled Receptors (MC1-5) that are stimulated by endogenous agonists and antagonized by the only two known endogenous antagonists of GPCRs, agouti and agouti-related protein (AGRP). These Receptors have been associated with many physiological functions, including the involvement of the MC4R in feeding behavior and energy homeostasis, making this system an attractive target for the treatment of obesity. Small-molecule mimetics of endogenous ligands may result in the development of compounds with properties more suitable for use as therapeutic agents. The research presented herein involves the synthesis and analysis of 12 Melanocortin Receptor agonists using the 1,4-benzodiazepine-2,5-dione template and is the first report of these derivatives as Melanocortin Receptor agonists. Structure-activity relationship studies using this privileged structure template has resulted in molecules with molecular weights around 400 that possess nanomolar agonist potency at the Melanocortin Receptors examined in this study.
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the 1 4 benzodiazepine 2 5 dione small molecule template results in Melanocortin Receptor agonists with nanomolar potencies
Journal of Medicinal Chemistry, 2008Co-Authors: Christine G. Joseph, Krista R. Wilson, Michael S. Wood, Nicholas B. Sorenson, Dong V. Phan, Zhimin Xiang, Rachel M. Witek, Carrie HaskellluevanoAbstract:The Melanocortin system consists of five seven-transmembrane spanning G-protein coupled Receptors (MC1−5) that are stimulated by endogenous agonists and antagonized by the only two known endogenous antagonists of GPCRs, agouti and agouti-related protein (AGRP). These Receptors have been associated with many physiological functions, including the involvement of the MC4R in feeding behavior and energy homeostasis, making this system an attractive target for the treatment of obesity. Small-molecule mimetics of endogenous ligands may result in the development of compounds with properties more suitable for use as therapeutic agents. The research presented herein involves the synthesis and analysis of 12 Melanocortin Receptor agonists using the 1,4-benzodiazepine-2,5-dione template and is the first report of these derivatives as Melanocortin Receptor agonists. Structure–activity relationship studies using this privileged structure template has resulted in molecules with molecular weights around 400 that possess...
Peta J Harvey - One of the best experts on this subject based on the ideXlab platform.
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development of novel Melanocortin Receptor agonists based on the cyclic peptide framework of sunflower trypsin inhibitor 1
Journal of Medicinal Chemistry, 2018Co-Authors: Thomas Durek, Philipp M Cromm, Andrew M White, Christina I Schroeder, Quentin Kaas, Joachim Weidmann, Abdullah Ahmad A H Fuaad, Olivier Cheneval, Peta J HarveyAbstract:Ultrastable cyclic peptide frameworks offer great potential for drug design due to their improved bioavailability compared to their linear analogues. Using the sunflower trypsin inhibitor-1 (SFTI-1) peptide scaffold in combination with systematic N-methylation of the grafted pharmacophore led to the identification of novel subtype selective Melanocortin Receptor (MCR) agonists. Multiple bicyclic peptides were synthesized and tested toward their activity at MC1R and MC3–5R. Double N-methylated compound 18 showed a pKi of 8.73 ± 0.08 (Ki = 1.92 ± 0.34 nM) and a pEC50 of 9.13 ± 0.04 (EC50 = 0.75 ± 0.08 nM) at the human MC1R and was over 100 times more selective for MC1R. Nuclear magnetic resonance structural analysis of 18 emphasized the role of peptide bond N-methylation in shaping the conformation of the grafted pharmacophore. More broadly, this study highlights the potential of cyclic peptide scaffolds for epitope grafting in combination with N-methylation to introduce Receptor subtype selectivity in the ...