Selective small molecule inhibitors of glycogen synthase kinase-3 modulate glycogen metabolism and gene transcription.
BACKGROUND
Glycogen synthase kinase-3 (GSK-3) is a serine/threonine protein kinase, the activity of which is inhibited by a variety of extracellular stimuli including insulin, growth factors, cell specification factors and cell adhesion. Consequently, inhibition of GSK-3 activity has been proposed to play a role in the regulation of numerous signalling pathways that elicit pleiotropic cellular responses. This report describes the identification and characterisation of potent and selective small molecule inhibitors of GSK-3.


RESULTS
SB-216763 and SB-415286 are structurally distinct maleimides that inhibit GSK-3alpha in vitro, with K(i)s of 9 nM and 31 nM respectively, in an ATP competitive manner. These compounds inhibited GSK-3beta with similar potency. However, neither compound significantly inhibited any member of a panel of 24 other protein kinases. Furthermore, treatment of cells with either compound stimulated responses characteristic of extracellular stimuli that are known to inhibit GSK-3 activity. Thus, SB-216763 and SB-415286 stimulated glycogen synthesis in human liver cells and induced expression of a beta-catenin-LEF/TCF regulated reporter gene in HEK293 cells. In both cases, compound treatment was demonstrated to inhibit cellular GSK-3 activity as assessed by activation of glycogen synthase, which is a direct target of this kinase.


CONCLUSIONS
SB-216763 and SB-415286 are novel, potent and selective cell permeable inhibitors of GSK-3. Therefore, these compounds represent valuable pharmacological tools with which the role of GSK-3 in cellular signalling can be further elucidated. Furthermore, development of similar compounds may be of use therapeutically in disease states associated with elevated GSK-3 activity such as non-insulin dependent diabetes mellitus and neurodegenerative disease.
Coghlan
M P
MP
Department of Vascular Biology, SmithKline Beecham Pharmaceuticals, Essex, UK. matthew_coghlan-1@sbphrd.com
Culbert
A A
AA
Cross
D A
DA
Corcoran
S L
SL
Yates
J W
JW
Pearce
N J
NJ
Rausch
O L
OL
Murphy
G J
GJ
Carter
P S
PS
Roxbee Cox
L
L
Mills
D
D
Brown
M J
MJ
Haigh
D
D
Ward
R W
RW
Smith
D G
DG
Murray
K J
KJ
Reith
A D
AD
Holder
J C
JC
D000255:Adenosine Triphosphate / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000627:Aminophenols / Q000494:pharmacology*; D001667:Binding, Competitive; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002460:Cell Line; D003598:Cytoskeletal Proteins / Q000235:genetics; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D004789:Enzyme Activation / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects*; D017930:Genes, Reporter; D006003:Glycogen / Q000096:biosynthesis / Q000378:metabolism*; D006006:Glycogen Synthase / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3; D038341:Glycogen Synthase Kinases; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D007700:Kinetics; D008099:Liver / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D008301:Maleimides / Q000494:pharmacology*; D015394:Molecular Structure; D019636:Neurodegenerative Diseases / Q000188:drug therapy; D011494:Protein Kinases / Q000378:metabolism; D011994:Recombinant Proteins; D015398:Signal Transduction / Q000187:drug effects; D015534:Trans-Activators; D014158:Transcription, Genetic / Q000187:drug effects*; D051176:beta Catenin
C417520:3-(3-chloro-4-hydroxyphenylamino)-4-(4-nitrophenyl)-1H-pyrrole-2,5-dione; D000627:Aminophenols; C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D007211:Indoles; D008301:Maleimides; D011994:Recombinant Proteins; C417521:SB 216763; D015534:Trans-Activators; D051176:beta Catenin; D000255:Adenosine Triphosphate; D006003:Glycogen; D006006:Glycogen Synthase; D011494:Protein Kinases; D038341:Glycogen Synthase Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D038362:Glycogen Synthase Kinase 3