Inhibition of vacuolar-type (H+)-ATPase by the cytostatic macrolide apicularen A and its role in apicularen A-induced apoptosis in RAW 264.7 cells.
Apicularen A and the known vacuolar-type (H(+))-ATPase (V-ATPase) inhibitor bafilomycin A(1) induced apoptosis of RAW 264.7 cells, while apicularen B, an N-acetyl-glucosamine glycoside of apicularen A, was far less effective. Apicularen A inhibited vital staining with acridine orange of the intracellular organelles of RAW 264.7 cells, inhibited the ATP-dependent proton transport into inside-out microsome vesicles, and inhibited the bafilomycin A(1)-sensitive ATP hydrolysis. The IC(50) values of the proton transport were 0.58 nM for apicularen A, 13 nM for apicularen B, and 0.95 nM for bafilomycin A(1). Furthermore, apicularen A inhibited the bafilomycin A(1)-sensitive ATP hydrolysis more potently than apicularen B. F-ATPase and P-ATPase were not inhibited by apicularen A. We concluded that apicularen A inhibits V-ATPase, and thus induces apoptosis in RAW 264.7 cells.
Hong
JangJa
J
Laboratory of Pathophysiological Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba Aramaki, Sendai, Miyagi 980-8578, Japan.
Yokomakura
Aya
A
Nakano
Yasuhiro
Y
Ishihara
Kenji
K
Kaneda
Makoto
M
Onodera
Mitsue
M
Nakahama
Ken-ichi
K
Morita
Ikuo
I
Niikura
Kazuaki
K
Ahn
Jong-Woong
JW
Zee
OkPyo
O
Ohuchi
Kazuo
K
D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D018942:Macrolides / Q000737:chemistry / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D051336:Mitochondrial Membranes / Q000187:drug effects; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors* / Q000378:metabolism
D019086:Bridged Bicyclo Compounds, Heterocyclic; D004791:Enzyme Inhibitors; D018942:Macrolides; C117813:apicularen A; C117814:apicularen B; C040929:bafilomycin A1; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases