5 research outputs found
Proposing Novel MAO‑B Hit Inhibitors Using Multidimensional Molecular Modeling Approaches and Application of Binary QSAR Models for Prediction of Their Therapeutic Activity, Pharmacokinetic and Toxicity Properties
Monoamine
oxidase (MAO) enzymes MAO-A and MAO-B play a critical role in the
metabolism of monoamine neurotransmitters. Hence, MAO inhibitors are
very important for the treatment of several neurodegenerative diseases
such as Parkinson’s disease (PD), Alzheimer’s disease
(AD), and amyotrophic lateral sclerosis (ALS). In this study, 256 750
molecules from Otava Green Chemical Collection were virtually screened
for their binding activities as MAO-B inhibitors. Two hit molecules
were identified after applying different filters such as high docking
scores and selectivity to MAO-B, desired pharmacokinetic profile predictions
with binary quantitative structure–activity relationship (QSAR)
models. Therapeutic activity prediction as well as pharmacokinetic
and toxicity profiles were investigated using MetaCore/MetaDrug platform
which is based on a manually curated database of molecular interactions,
molecular pathways, gene–disease associations, chemical metabolism,
and toxicity information. Particular therapeutic activity and toxic
effect predictions are based on the ChemTree ability to correlate
structural descriptors to that property using recursive partitioning
algorithm. Molecular dynamics (MD) simulations were also performed
to make more detailed assessments beyond docking studies. All these
calculations were made not only to determine if studied molecules
possess the potential to be a MAO-B inhibitor but also to find out
whether they carry MAO-B selectivity versus MAO-A. The evaluation
of docking results and pharmacokinetic profile predictions together
with the MD simulations enabled us to identify one hit molecule (ligand <b>1</b>, Otava ID: 3463218) which displayed higher selectivity toward
MAO-B than a positive control selegiline which is a commercially used
drug for PD therapeutic purposes
Biological Insights of the Dopaminergic Stabilizer ACR16 at the Binding Pocket of Dopamine D2 Receptor
The
dopamine D2 receptor (D2R) plays an important part in the human
central nervous system and it is considered to be a focal target of
antipsychotic agents. It is structurally modeled in active and inactive
states, in which homodimerization reaction of the D2R monomers is
also applied. The ASP2314 (also known as ACR16) ligand, a D2R stabilizer,
is used in tests to evaluate how dimerization and conformational changes
may alter the ligand binding space and to provide information on alterations
in inhibitory mechanisms upon activation. The administration of the
D2R agonist ligand ACR16 [<sup>3</sup>H]Â(+)-4-propyl-3,4,4<i>a</i>,5,6,10<i>b</i>-hexahydro-2<i>H</i>-naphthoÂ[1,2-<i>b</i>]Â[1,4]Âoxazin-9-ol ((+)ÂPHNO) revealed <i>K</i><sub>i</sub> values of 32 nM for the D2<sup>high</sup>R
and 52 μM for the D2<sup>low</sup>R. The calculated binding
affinities of ACR16 with post processing molecular dynamics (MD) simulations
analyses using MM/PBSA for the monomeric and homodimeric forms of
the D2<sup>high</sup>R were −9.46 and −8.39 kcal/mol,
respectively. The data suggests that the dimerization of the D2R leads
negative cooperativity for ACR16 binding. The dimerization reaction
of the D2<sup>high</sup>R is energetically favorable by −22.95
kcal/mol. The dimerization reaction structurally and thermodynamically
stabilizes the D2<sup>high</sup>R conformation, which may be due to
the intermolecular forces formed between the TM4 of each monomer,
and the result strongly demonstrates dimerization essential for activation
of the D2R
Analysis of the Glutamate Agonist LY404,039 Binding to Nonstatic Dopamine Receptor D2 Dimer Structures and Consensus Docking
Dopamine receptor D2 (D2R) plays
an important role in the human
central nervous system and is a focal target of antipsychotic agents.
The D2<sup>High</sup>R and D2<sup>Low</sup>R dimeric models previously
developed by our group are used to investigate the prediction of binding
affinity of the LY404,039 ligand and its binding mechanism within
the catalytic domain. The computational data obtained using molecular
dynamics simulations fit well with the experimental results. The calculated
binding affinities of LY404,039 using MM/PBSA for the D2<sup>High</sup>R and D2<sup>Low</sup>R targets were −12.04 and −9.11
kcal/mol, respectively. The experimental results suggest that LY404,039
binds to D2<sup>High</sup>R and D2<sup>Low</sup>R with binding affinities
(<i>K</i><sub>i</sub>) of 8.2 and 1640 nM, respectively.
The high binding affinity of LY404,039 in terms of binding to [<sup>3</sup>H]Âdomperidone was inhibited by the presence of a guanine nucleotide,
indicating an agonist action of the drug at D2<sup>High</sup>R. The
interaction analysis demonstrated that while Asp114 was among the
most critical amino acids for D2<sup>High</sup>R binding, residues
Ser193 and Ser197 were significantly more important within the binding
cavity of D2<sup>Low</sup>R. Molecular modeling analyses are extended
to ensemble docking as well as structure-based pharmacophore model
(E-pharmacophore) development using the bioactive conformation of
LY404,039 at the binding pocket as a template and screening of small-molecule
databases with derived pharmacophore models
Analysis of the Glutamate Agonist LY404,039 Binding to Nonstatic Dopamine Receptor D2 Dimer Structures and Consensus Docking
Dopamine receptor D2 (D2R) plays
an important role in the human
central nervous system and is a focal target of antipsychotic agents.
The D2<sup>High</sup>R and D2<sup>Low</sup>R dimeric models previously
developed by our group are used to investigate the prediction of binding
affinity of the LY404,039 ligand and its binding mechanism within
the catalytic domain. The computational data obtained using molecular
dynamics simulations fit well with the experimental results. The calculated
binding affinities of LY404,039 using MM/PBSA for the D2<sup>High</sup>R and D2<sup>Low</sup>R targets were −12.04 and −9.11
kcal/mol, respectively. The experimental results suggest that LY404,039
binds to D2<sup>High</sup>R and D2<sup>Low</sup>R with binding affinities
(<i>K</i><sub>i</sub>) of 8.2 and 1640 nM, respectively.
The high binding affinity of LY404,039 in terms of binding to [<sup>3</sup>H]Âdomperidone was inhibited by the presence of a guanine nucleotide,
indicating an agonist action of the drug at D2<sup>High</sup>R. The
interaction analysis demonstrated that while Asp114 was among the
most critical amino acids for D2<sup>High</sup>R binding, residues
Ser193 and Ser197 were significantly more important within the binding
cavity of D2<sup>Low</sup>R. Molecular modeling analyses are extended
to ensemble docking as well as structure-based pharmacophore model
(E-pharmacophore) development using the bioactive conformation of
LY404,039 at the binding pocket as a template and screening of small-molecule
databases with derived pharmacophore models
Synthesis, biological activity and multiscale molecular modeling studies for coumaryl-carboxamide derivatives as selective carbonic anhydrase IX inhibitors
<p>New coumaryl-carboxamide derivatives with the thiourea moiety as a linker between the alkyl chains and/or the heterocycle nucleus were synthesized and their inhibitory activity against the human carbonic anhydrase (hCA) isoforms hCA I, II, VII and IX were evaluated. While the hCA I, II and VII isoforms were not inhibited by the investigated compounds, the tumour-associated isoform hCA IX was inhibited in the high nanomolar range. 2-Oxo-<i>N</i>-((2-(pyrrolidin-1-yl)ethyl)carbamothioyl)-<i>2H</i>-chromene-3-carboxamide (<b>e11</b>) exhibited a selective inhibitory action against hCA IX with the <i>K</i><sub>i</sub> of 107.9 nM. In order to better understand the inhibitory profiles of studied molecules, multiscale molecular modeling approaches were used. Different molecular docking algorithms were used to investigate binding poses and predicted binding energies of studied compounds at the active sites of the CA I, II, VII and IX isoforms.</p