TY - JOUR
T1 - Structure-Activity Relationship, Pharmacological Characterization, and Molecular Modeling of Noncompetitive Inhibitors of the Betaine/γ-Aminobutyric Acid Transporter 1 (BGT1)
AU - Jørgensen, Lars
AU - Al-Khawaja, Anas
AU - Kickinger, Stefanie
AU - Vogensen, Stine B
AU - Skovgaard-Petersen, Jonas
AU - Rosenthal, Emil
AU - Borkar, Nrupa
AU - Löffler, Rebekka
AU - Madsen, Karsten K
AU - Bräuner-Osborne, Hans
AU - Schousboe, Arne
AU - Ecker, Gerhard F
AU - Wellendorph, Petrine
AU - Clausen, Rasmus P
PY - 2017/11/9
Y1 - 2017/11/9
N2 - N-(1-Benzyl-4-piperidinyl)-2,4-dichlorobenzamide 5 (BPDBA) is a noncompetitive inhibitor of the betaine/GABA transporter 1 (BGT1). We here report the synthesis and structure-activity relationship of 71 analogues. We identify 26m as a more soluble 2,4-Cl substituted 3-pyridine analogue with retained BGT1 activity and an improved off-target profile compared to 5. We performed radioligand-based uptake studies at chimeric constructs between BGT1 and GAT3, experiments with site-directed mutated transporters, and computational docking in a BGT1 homology model based on the newly determined X-ray crystal structure of the human serotonin transporter (hSERT). On the basis of these experiments, we propose a binding mode involving residues within TM10 in an allosteric site in BGT1 that corresponds to the allosteric binding pocket revealed by the hSERT crystal structure. Our study provides first insights into a proposed allosteric binding pocket in BGT1, which accommodates the binding site for a series of novel noncompetitive inhibitors.
AB - N-(1-Benzyl-4-piperidinyl)-2,4-dichlorobenzamide 5 (BPDBA) is a noncompetitive inhibitor of the betaine/GABA transporter 1 (BGT1). We here report the synthesis and structure-activity relationship of 71 analogues. We identify 26m as a more soluble 2,4-Cl substituted 3-pyridine analogue with retained BGT1 activity and an improved off-target profile compared to 5. We performed radioligand-based uptake studies at chimeric constructs between BGT1 and GAT3, experiments with site-directed mutated transporters, and computational docking in a BGT1 homology model based on the newly determined X-ray crystal structure of the human serotonin transporter (hSERT). On the basis of these experiments, we propose a binding mode involving residues within TM10 in an allosteric site in BGT1 that corresponds to the allosteric binding pocket revealed by the hSERT crystal structure. Our study provides first insights into a proposed allosteric binding pocket in BGT1, which accommodates the binding site for a series of novel noncompetitive inhibitors.
KW - Journal Article
U2 - 10.1021/acs.jmedchem.7b00924
DO - 10.1021/acs.jmedchem.7b00924
M3 - Journal article
C2 - 28991462
SN - 0022-2623
VL - 60
SP - 8834
EP - 8846
JO - Journal of Medicinal Chemistry
JF - Journal of Medicinal Chemistry
IS - 21
ER -