Competitive inhibition of cytosolic Ca2+-dependent phospholipase A2 by acteoside in RBL-2H3 cells.
The aim of this study was to investigate whether acteoside isolated from Clerodendron trichotomum Thunberg may act as a selective inhibitor of phospholipase A(2) in RBL-2H3 cells. Acteoside dose-dependently inhibited 0.5 μM melittin-induced release of [(3)H]arachidonic acid, which was due to the inhibition of cytosolic Ca(2+)-dependent phospholipase A(2) (cPLA(2)) rather than secretory PLA(2) (sPLA(2)). In Dixon plots, the apparent K ( i ) value of acteoside on cPLA(2) was 5.9 μM and the inhibitory pattern appeared to be a competitive inhibitor. The above data, suggests that acteoside acts as a competitive inhibitor of cPLA(2) in RBL-2H3 cells.
College of Pharmacy, Chung-Ang University, Seoul, Korea.
Ho Sun
HS
Song
Mi Young
MY
Choi
Myoung Soo
MS
Ko
Jae Min
JM
Jeong
Yong Ho
YH
Kim
Beom Hyeon
BH
Jang
Ji Hoon
JH
Sung
Min Gyu
MG
Kim
Wan Kyunn
WK
Whang
Sang Soo
SS
Sim
D000818:Animals; D001514:Bee Venoms; D001516:Bees; D001667:Binding, Competitive / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D032409:Clerodendrum; D005960:Glucosides / Q000302:isolation & purification / Q000494:pharmacology*; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*; D054510:Phospholipases A2, Cytosolic / Q000037:antagonists & inhibitors* / Q000378:metabolism; D051381:Rats; D029648:Verbenaceae; D059808:Polyphenols
D001514:Bee Venoms; D005960:Glucosides; D010636:Phenols; D054510:Phospholipases A2, Cytosolic; C058956:acteoside; D059808:Polyphenols