The anti-platelet effects of apocynin in mice are not mediated by inhibition of NADPH oxidase activity

被引:24
作者
Dharmarajah, Janahan [1 ]
Arthur, Jane F. [2 ]
Sobey, Christopher G. [1 ]
Drummond, Grant R. [1 ]
机构
[1] Monash Univ, Dept Pharmacol, Vasc Biol & Immunopharmacol Grp, Clayton, Vic 3800, Australia
[2] Monash Univ, Australian Ctr Blood Dis, Melbourne, Vic 3004, Australia
基金
英国医学研究理事会; 澳大利亚国家健康与医学研究理事会;
关键词
NADPH oxidase; Nox2; Reactive oxygen species; Apocynin; Platelets; Collagen; PLATELET ACTIVATION; RHO-KINASE; INVOLVEMENT; DISEASE; ROLES;
D O I
10.1007/s00210-010-0552-3
中图分类号
R9 [药学];
学科分类号
1007 ;
摘要
Apocynin, or a (myelo)peroxidase-derived product thereof, is a powerful inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Apocynin has also been shown to prevent aggregation of platelets in response to agonists such as collagen and thrombin. The aims of this study were to establish whether NADPH oxidase activity is required for aggregation of murine platelets to collagen and other agonists and whether the anti-aggregatory effects of apocynin are due to an inhibitory action against this enzyme. Washed platelets were isolated from male C57BL6 (wild-type), Nox2-deficient (Nox2(-/y) ), and p47phox-deficient (p47phox(-/-)) mice for assessment of aggregation and NADPH oxidase subunit (Nox2, p47phox) expression. Collagen and U46619 elicited aggregation of murine platelets, and these responses were inhibited by apocynin at concentrations a parts per thousand yen100 mu M. By contrast, aggregations to a direct protein kinase C activator, phorbol-12,13-dibutyrate, were insensitive to apocynin. Immunoblotting of platelet protein homogenates from wild-type mice with anti-Nox2 or p47phox antibodies revealed strong bands at 58 and 50 kDa, respectively. While expression of these immunoreactive bands was greatly diminished in platelets from Nox2(-/y) and p47phox(-/-) mice, collagen still elicited aggregations that were similar to those observed in platelets from wild-types. Moreover, apocynin was an equally effective inhibitor of aggregation in platelets from all three mouse strains. In conclusion, these data suggest that NADPH oxidase-derived reactive oxygen species play no role in the aggregation response of washed murine platelets to collagen. Thus, our observation that apocynin is a powerful inhibitor of platelet aggregation raises further questions about the selectivity of this drug as an NADPH oxidase inhibitor.
引用
收藏
页码:377 / 384
页数:8
相关论文
共 33 条
[1]   Noxal is a central component of the smooth muscle NADPH oxidase in mice [J].
Ambasta, Rashmi K. ;
Schreiber, Judith G. ;
Janiszewski, Mariano ;
Busse, Rudi ;
Brandes, Ralf P. .
FREE RADICAL BIOLOGY AND MEDICINE, 2006, 41 (02) :193-201
[2]   Platelet physiology and thrombosis [J].
Andrews, RK ;
Berndt, MC .
THROMBOSIS RESEARCH, 2004, 114 (5-6) :447-453
[3]   Platelet receptor redox regulation [J].
Arthur, Jane F. ;
Gardiner, Elizabeth E. ;
Kenny, Dermot ;
Andrews, Robert K. ;
Berndt, Michael C. .
PLATELETS, 2008, 19 (01) :1-8
[4]   Inhibitory effect of reinioside C on monocyte-endothelial cell adhesion induced by oxidized low-density lipoprotein via inhibiting NADPH oxidase/ROS/NF-κB pathway [J].
Bai, Yong-Ping ;
Hu, Chang-ping ;
Chen, Mei-Fang ;
Xu, Kang-Ping ;
Tan, Gui-Shan ;
Shi, Rui-Zhen ;
Li, Yuan-Jian ;
Zhang, Guo-Gang .
NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY, 2009, 380 (05) :399-406
[5]   Spatially distinct production of reactive oxygen species regulates platelet activation [J].
Bakdash, Nadia ;
Williams, Mark S. .
FREE RADICAL BIOLOGY AND MEDICINE, 2008, 45 (02) :158-166
[6]   Platelet NAD(P)H-oxidase-generated ROS production regulates αIIbβ3-integrin activation independent of the NO/cGMP pathway [J].
Begonja, AJ ;
Gambaryan, S ;
Geiger, J ;
Aktas, B ;
Pozgajova, M ;
Nieswandt, B ;
Walter, U .
BLOOD, 2005, 106 (08) :2757-2760
[7]   Cloning of murine gp91(phox) cDNA and functional expression in a human X-linked chronic granulomatous disease cell line [J].
Bjorgvinsdottir, H ;
Zhen, L ;
Dinauer, MC .
BLOOD, 1996, 87 (05) :2005-2010
[8]   Nox proteins in signal transduction [J].
Brown, David I. ;
Griendling, Kathy K. .
FREE RADICAL BIOLOGY AND MEDICINE, 2009, 47 (09) :1239-1253
[9]   Segmental differences in the roles of rho-kinase and protein kinase C in mediating vasoconstriction [J].
Budzyn, K ;
Paull, M ;
Marley, PD ;
Sobey, CG .
JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS, 2006, 317 (02) :791-796
[10]   Functional role of NADPH oxidase in activation of platelets [J].
Chlopicki, S ;
Olszanecki, R ;
Janiszewski, M ;
Laurindo, FRM ;
Panz, T ;
Miedzobrodzki, J .
ANTIOXIDANTS & REDOX SIGNALING, 2004, 6 (04) :691-698