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Mar Drugs
2014 Mar 28;124:1859-75. doi: 10.3390/md12041859.
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Marine natural products acting on the acetylcholine-binding protein and nicotinic receptors: from computer modeling to binding studies and electrophysiology.
Kudryavtsev D, Makarieva T, Utkina N, Santalova E, Kryukova E, Methfessel C, Tsetlin V, Stonik V, Kasheverov I.
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For a small library of natural products from marine sponges and ascidians, in silico docking to the Lymnaea stagnalis acetylcholine-binding protein (AChBP), a model for the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs), was carried out and the possibility of complex formation was revealed. It was further experimentally confirmed via competition with radioiodinated α-bungarotoxin ([¹²⁵I]-αBgt) for binding to AChBP of the majority of analyzed compounds. Alkaloids pibocin, varacin and makaluvamines С and G had relatively high affinities (K(i) 0.5-1.3 μM). With the muscle-type nAChR from Torpedo californica ray and human neuronal α7 nAChR, heterologously expressed in the GH4C1 cell line, no competition with [¹²⁵I]-αBgt was detected in four compounds, while the rest showed an inhibition. Makaluvamines (K(i) ~ 1.5 μM) were the most active compounds, but only makaluvamine G and crambescidine 359 revealed a weak selectivity towards muscle-type nAChR. Rhizochalin, aglycone of rhizochalin, pibocin, makaluvamine G, monanchocidin, crambescidine 359 and aaptamine showed inhibitory activities in electrophysiology experiments on the mouse muscle and human α7 nAChRs, expressed in Xenopus laevis oocytes. Thus, our results confirm the utility of the modeling studies on AChBPs in a search for natural compounds with cholinergic activity and demonstrate the presence of the latter in the analyzed marine biological sources.
Figure 1. Chemical structures of compounds from marine sponges and ascidians (1–13), for which putative cholinergic activities were examined by computational and experimental methods.
Figure 2. Inhibition of [125I]-αBgt binding to L. stagnalis AChBP with the most active compounds studied. Numbering the compounds corresponds to the numbering in Figure 1. The corresponding curves are marked with symbols: 1—filled circles; 2—open circles; 3—filled squares; 4—open squares; 5—filled diamonds; 6—open diamonds; 9—open triangles; 12—filled triangles; 13—stars. Each point is a mean ± s.e.m value of two or three measurements for each concentration. The curves were calculated from the means ± s.e.m. using ORIGIN 7.5 program (see Experimental Section). The respective Ki values are listed in Table 1.
Figure 3. Schematic planar image of the model of makaluvamine G (6) docked to HEPES-bound form of L. stagnalis AChBP binding site (a) in comparison with the same presentation of the X-ray structure of the complex of the same protein with clothianidin (PDB ID—2ZJV) (b); intermolecular bonds in ligands are colored in magenta; the same links in the AChBP amino acid residues involved in the formation of hydrogen bonds (green lines) are shown in orange. The AChBP amino acid residues forming hydrophobic contacts with ligands are presented as red combs. Those of them that are the same for both ligands are encircled by red lines. Atoms of carbon, oxygen, nitrogen, and sulfur are colored in black, red, blue and yellow, respectively. Water molecule involved in the formation of hydrogen bonds is shown in cyan; (c) superposition of 3D structures of makaluvamine G (6), docked to AChBP and crystal structure of clothianidine AChBP complex. Carbons of makaluvamine G (6), clothianidine and AChBP are shown in light blue, pink and grey respectively; oxygens are shown red, nitrogens are shown blue; hydrogen bonds are brown; (d) superposition of α-cobratoxin structure (blue) (PDB ID—1YI5) and the best solution for debromohymenialdesine (7) (magenta) in silico docked to L. stagnalis AChBP (gray).
Figure 4. Inhibition of initial rate for [125I]-αBgt binding to T. californica nAChR (a) or human α7 nAChR (b) with the most active compounds studied. Numbering the compounds and their symbols correspond to the numbering in Figure 1 and symbols in Figure 2, respectively. Each point is a mean ± s.e.m value of two or three measurements for each concentration. The curves were calculated from the means ± s.e.m. using the ORIGIN 7.5 program (see Experimental Section). The respective Ki values are listed in Table 2.
Figure 5. Relative inhibition of agonist-evoked current by 10 μM compounds on murine muscle-type nAChR (a) and on human α7 nAChR (b). Numbering the compounds in x axis corresponds to the numbering in Figure 1. Asterisks indicate significant (p < 0.05, according to Student’s test) differences between inhibition effects on murine muscle- and human α7 nAChRs for compounds (4), (6) and (11).
Figure 6. Electrophysiological measurements of 10 μM rhizochalin (1) (a) and makaluvamine G (6) (b) activity on muscle nAChR. Black and grey rectangles represent application of acetylcholine and tested compound, respectively. From left to right: control acetylcholine-evoked current, acetylcholine-evoked current in the presence of tested compound and acetylcholine-evoked current after 15 min of wash out. Current inhibition dose-response curves (c): concentrations of tested compounds from 1 to 100 μM were used to evaluate IC50 (values placed on figure according to numbering from Figure 1). The symbols used for the respective compounds are the same as in Figure 2 and Figure 4.
Akdemir,
Acetylcholine binding protein (AChBP) as template for hierarchical in silico screening procedures to identify structurally novel ligands for the nicotinic receptors.
2011, Pubmed
Akdemir,
Acetylcholine binding protein (AChBP) as template for hierarchical in silico screening procedures to identify structurally novel ligands for the nicotinic receptors.
2011,
Pubmed Bourne,
Structural determinants in phycotoxins and AChBP conferring high affinity binding and nicotinic AChR antagonism.
2010,
Pubmed
,
Xenbase Bourne,
Crystal structure of a Cbtx-AChBP complex reveals essential interactions between snake alpha-neurotoxins and nicotinic receptors.
2005,
Pubmed Braekman,
Novel polycyclic guanidine alkaloids from two marine sponges of the genus Monanchora.
2000,
Pubmed Brams,
A structural and mutagenic blueprint for molecular recognition of strychnine and d-tubocurarine by different cys-loop receptors.
2011,
Pubmed Celie,
Nicotine and carbamylcholine binding to nicotinic acetylcholine receptors as studied in AChBP crystal structures.
2004,
Pubmed Chang,
Looking back on the discovery of alpha-bungarotoxin.
1999,
Pubmed Changeux,
The nicotinic acetylcholine receptor: the founding father of the pentameric ligand-gated ion channel superfamily.
2012,
Pubmed Guzii,
Monanchocidin: a new apoptosis-inducing polycyclic guanidine alkaloid from the marine sponge Monanchora pulchra.
2010,
Pubmed Halai,
Conotoxins: natural product drug leads.
2009,
Pubmed Hanwell,
Avogadro: an advanced semantic chemical editor, visualization, and analysis platform.
2012,
Pubmed Ihara,
Crystal structures of Lymnaea stagnalis AChBP in complex with neonicotinoid insecticides imidacloprid and clothianidin.
2008,
Pubmed Jeong,
1,3-dimethylisoguaninium, an antiangiogenic purine analog from the sponge Amphimedon paraviridis.
2003,
Pubmed Kalamida,
Muscle and neuronal nicotinic acetylcholine receptors. Structure, function and pathogenicity.
2007,
Pubmed Kasheverov,
Interaction of alpha-conotoxin ImII and its analogs with nicotinic receptors and acetylcholine-binding proteins: additional binding sites on Torpedo receptor.
2009,
Pubmed
,
Xenbase Kasheverov,
Alpha-conotoxin analogs with additional positive charge show increased selectivity towards Torpedo californica and some neuronal subtypes of nicotinic acetylcholine receptors.
2006,
Pubmed Kasheverov,
Naturally occurring and synthetic peptides acting on nicotinic acetylcholine receptors.
2009,
Pubmed Kasheverov,
Design of new α-conotoxins: from computer modeling to synthesis of potent cholinergic compounds.
2011,
Pubmed Kini,
Structure, function and evolution of three-finger toxins: mini proteins with multiple targets.
2010,
Pubmed Laskowski,
LigPlot+: multiple ligand-protein interaction diagrams for drug discovery.
2011,
Pubmed Lewis,
Conus venom peptide pharmacology.
2012,
Pubmed Liao,
Effects of cartap on isolated mouse phrenic nerve diaphragm and its related mechanism.
2000,
Pubmed Lyukmanova,
Water-soluble LYNX1 residues important for interaction with muscle-type and/or neuronal nicotinic receptors.
2013,
Pubmed Makarieva,
Varacin and three new marine antimicrobial polysulfides from the far-eastern ascidian Polycitor sp.
1995,
Pubmed Molinski,
(-)-Rhizochalin is a Dimeric Enantiomorphic (2R)-Sphingolipid: Absolute Configuration of Pseudo-C(2v)-Symmetric Bis-2-amino-3-alkanols by CD We thank Jeff de Ropp and John MacMillan (University of California, Davis) for assistance with the 600 and 400 MHz (1)H NMR spectra, respectively; Gillian Nicholas (University of California, Davis) for measurement of the CD spectra of 7 a, b; Rich Kondrat (University of California, Riverside Mass Spectrometry Facility) for chemical ionization MS; and Carlito Lebrilla
2000,
Pubmed Morris,
AutoDock4 and AutoDockTools4: Automated docking with selective receptor flexibility.
2009,
Pubmed Prickaerts,
EVP-6124, a novel and selective α7 nicotinic acetylcholine receptor partial agonist, improves memory performance by potentiating the acetylcholine response of α7 nicotinic acetylcholine receptors.
2012,
Pubmed Rucktooa,
Insight in nAChR subtype selectivity from AChBP crystal structures.
2009,
Pubmed Santalova,
Dibromotyrosine and histamine derivatives from the tropical marine sponge Aplysina sp.
2010,
Pubmed Shahsavar,
Crystal structure of Lymnaea stagnalis AChBP complexed with the potent nAChR antagonist DHβE suggests a unique mode of antagonism.
2012,
Pubmed Shubina,
Aaptamine alkaloids from the Vietnamese sponge Aaptos sp.
2009,
Pubmed Sine,
Recent advances in Cys-loop receptor structure and function.
2006,
Pubmed Teichert,
Natural products and ion channel pharmacology.
2010,
Pubmed Tsetlin,
Nicotinic acetylcholine receptors at atomic resolution.
2009,
Pubmed Tsetlin,
Snake venom alpha-neurotoxins and other 'three-finger' proteins.
1999,
Pubmed Tsuneki,
Marine alkaloids (-)-pictamine and (-)-lepadin B block neuronal nicotinic acetylcholine receptors.
2005,
Pubmed
,
Xenbase Ulens,
Use of acetylcholine binding protein in the search for novel alpha7 nicotinic receptor ligands. In silico docking, pharmacological screening, and X-ray analysis.
2009,
Pubmed
,
Xenbase Utkin,
"Weak toxin" from Naja kaouthia is a nontoxic antagonist of alpha 7 and muscle-type nicotinic acetylcholine receptors.
2001,
Pubmed
,
Xenbase Yakel,
Gating of nicotinic ACh receptors: latest insights into ligand binding and function.
2010,
Pubmed
