A prenylated flavonol, sophoflavescenol: a potent and selective inhibitor of cGMP phosphodiesterase 5.
During the search for naturally occurring cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5) inhibitors, it was found that the extracts from Sophora flavescens exhibit potent inhibitory activity against cGMP PDE5 prepared from rat diaphragm. Therefore, the inhibitory activities of five flavonoids, kushenol H (1), kushenol K (2), kurarinol (3), sophoflavescenol (4) and kuraridine (5), isolated from S. flavescens were measured against cGMP PDE5 to identify potent cGMP PDE5 inhibitory constituents. Among tested compounds, sophoflavescenol (4), a C-8 prenylated flavonol, showed the most potent inhibitory activity (IC(50)=0.013 microM) against cGMP PDE5 with 31.5- and 196.2-fold selectivity over PDE3 and PDE4, respectively. Kinetic analysis revealed that sophoflavescenol was a mixed inhibitor of PDE5 with a K(i) value of 0.005 microM.
Shin
Hye Joo
HJ
Division of Life Sciences, Korea Institute of Science & Technology, Cheongryang, Seoul, Republic of Korea.
Kim
Hyoung Ja
HJ
Kwak
Jong Hwan
JH
Chun
Hyung Ok
HO
Kim
Je Hak
JH
Park
Hokoon
H
Kim
Dong Hyun
DH
Lee
Yong Sup
YS
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors; D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000037:antagonists & inhibitors*; D000818:Animals; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D007700:Kinetics; D051381:Rats; D029909:Sophora / Q000737:chemistry; D013329:Structure-Activity Relationship
D004791:Enzyme Inhibitors; D005419:Flavonoids; C117237:sophoflavescenol; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517384:Pde5a protein, rat