Differential effects of mitochondrial Complex I inhibitors on production of reactive oxygen species.
Differential effects of mitochondrial Complex I inhibitors on production of reactive oxygen species.
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DOI：
10.1016/j.bbabio.2008.11.003
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发表时间：
2009-05
影响因子：
4.3
通讯作者：
Lenaz, Giorgio
中科院分区：
文献类型：
--
作者：
Fato, Romana;Bergamini, Christian;Bortolus, Marco;Maniero, Anna Lisa;Leoni, Serena;Ohnishi, Tomoko;Lenaz, Giorgio
关键词：
我们用2′，7 ′-二氯二氢荧光素二乙酸酯（2′，7 ′-Dichlorodihydrofluorescein diacetate，2′，7 ′-Dichlorodihydrofluorescein diacetate，2′，7 ′-Dichlorodihydrofluorescein diacetate）作探针，研究了在NADH存在下，牛离体心脏亚线粒体膜碎片在正向电子传递过程中复合物I产生活性氧（reactive oxygen species，ROS）的情况。复合物I的ROS产生与其抑制状态严格相关。我们的研究结果表明，不同的复合物I抑制剂可以分为两类：A类抑制剂（鱼藤酮，杀粉蝶菌素A和Rolliniastatin 1和2）增加ROS的产生; B类抑制剂（Stigmatellin，粘蛋白，辣椒素和辅酶Q2）防止ROS的产生也在A类抑制剂的存在下。添加亲水性辅酶Q1作为电子受体可增强鱼藤酮样抑制剂增加ROS产生的作用，但在Stigmatellin样抑制剂存在下无作用;该作用不被更疏水的醌类（如癸基鲁比醌）共享。这种行为涉及到一个亲水性电子逃逸网站的促氧化辅酶Q1活性。此外，两类复合物I抑制剂对由短链醌诱导的NADH-DCIP还原的增加具有相反的作用：仅B类抑制剂允许这种增加，表明在酶的活性位点存在鱼藤酮敏感但Stigmatellin不敏感的半醌物质。这种半醌的存在也建议由初步EPR数据。结果表明，电子转移从铁硫簇（N2）辅酶Q发生在两个步骤门控由两种不同的构象，前者是敏感的鱼藤酮和后者Stigmatellin。
We have investigated the production of reactive oxygen species (ROS) by Complex I in isolated open bovine heart submitochondrial membrane fragments during forward electron transfer in presence of NADH, by means of the probe 2′,7′-Dichlorodihydrofluorescein diacetate. ROS production by Complex I is strictly related to its inhibited state. Our results indicate that different Complex I inhibitors can be grouped into two classes: Class A inhibitors (Rotenone, Piericidin A and Rolliniastatin 1 and 2) increase ROS production; Class B inhibitors (Stigmatellin, Mucidin, Capsaicin and Coenzyme Q2) prevent ROS production also in the presence of Class A inhibitors. Addition of the hydrophilic Coenzyme Q1 as an electron acceptor potentiates the effect of Rotenone-like inhibitors in increasing ROS production, but has no effect in the presence of Stigmatellin-like inhibitors; the effect is not shared by more hydrophobic quinones such as decylubiquinone. This behaviour relates the prooxidant CoQ1 activity to a hydrophilic electron escape site. Moreover the two classes of Complex I inhibitors have an opposite effect on the increase of NADH–DCIP reduction induced by short chain quinones: only Class B inhibitors allow this increase, indicating the presence of a Rotenone-sensitive but Stigmatellin-insensitive semiquinone species in the active site of the enzyme. The presence of this semiquinone was also suggested by preliminary EPR data. The results suggest that electron transfer from the iron–sulphur clusters (N2) to Coenzyme Q occurs in two steps gated by two different conformations, the former being sensitive to Rotenone and the latter to Stigmatellin.
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影响因子：
7
作者：
Carroll, J;Fearnley, IM;Walker, JE
通讯作者：
Walker, JE
影响因子：
3
作者：
Kerscher, S;Kashani-Poor, N;Brandt, U
通讯作者：
Brandt, U
DOI：
10.1073/pnas.0510977103
发表时间：
2006-05-16
影响因子：
11.1
作者：
Kussmaul, Lothar;Hirst, Judy
通讯作者：
Hirst, Judy
DOI：
10.1006/bbrc.1993.1161
发表时间：
1993-02-15
影响因子：
3.1
作者：
ESPOSTI, MD;GHELLI, A;LENAZ, G
通讯作者：
LENAZ, G
影响因子：
4.8
作者：
Garofano, A;Zwicker, K;Brandt, U
通讯作者：
Brandt, U