Phorbol ester induces elevated oxidative activity and alkalization in a subset of lysosomes.
Phorbol ester induces elevated oxidative activity and alkalization in a subset of lysosomes.
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佛波酯可诱导一部分溶酶体氧化活性升高和碱化。
DOI：
10.1186/1471-2121-3-21
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发表时间：
2002-08-06
期刊：
影响因子：
--
通讯作者：
Chen CS
中科院分区：
文献类型：
--
作者：
Chen CS
溶酶体是酸性细胞器，在各种细胞氧化活性中发挥多种作用，例如细胞毒性杀伤期间的氧化爆发。溶酶体腔氧化活性和pH如何相互作用和调节仍有待确定。在这里，我报告了使用荧光探针来测量用肿瘤促进剂佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）处理的活巨噬细胞中溶酶体的氧化活性和pH，并提供了关于溶酶体氧化活性和pH调节的新见解。用于测量氧化活性的底物是共价偶联到二氢-2 '，4，5，6，7，7 '-六氟荧光素（OxyBURST绿色H2 HFF BSA）。在活巨噬细胞的脉冲追踪程序中，这种还原染料通过内吞途径内化并在溶酶体中积累。该化合物的氧化导致荧光强度急剧增加。通过使用低光水平荧光显微镜，我确定佛波酯治疗的结果增加氧化活性和pH值升高的不同子集的溶酶体。此外，具有较强氧化活性的溶酶体倾向于排除亲酸溶酶体指示剂，因此表现出较高的碱性。结果表明，溶酶体氧化活性与pH之间存在调节机制，佛波醇酯激活溶酶体NADPH氧化酶，可导致溶酶体内O2·-和H2 O2增加，同时消耗H+，产生OH-，使pH升高。此外，佛波酯对氧化活性和pH升高的影响在总溶酶体群体中是不均匀的。较高的氧化活性和/或pH值仅在溶酶体亚群中观察到。
Lysosomes are acidic organelles that play multiple roles in various cellular oxidative activities such as the oxidative burst during cytotoxic killing. It remains to be determined how lysosomal lumen oxidative activity and pH interact and are regulated. Here, I report the use of fluorescent probes to measure oxidative activity and pH of lysosomes in live macrophages upon treatment with the tumor promotor phorbol 12-myristate 13-acetate (PMA), and provide novel insight regarding the regulation of lysosomal oxidative activity and pH. The substrate used to measure oxidative activity was bovine serum albumin covalently coupled to dihydro-2', 4,5,6,7,7'-hexafluorofluorescein (OxyBURST Green H2HFF BSA). During pulse-chase procedures with live macrophages, this reduced dye was internalized via an endocytic pathway and accumulated in the lysosomes. Oxidation of this compound resulted in a dramatic increase of fluorescence intensity. By using low-light level fluorescence microscopy, I determined that phorbol ester treatment results in increased oxidative activity and pH elevation in different subsets of lysosomes. Furthermore, lysosomes with stronger oxidative activity tended to exclude the acidotropic lysosomal indicator, and thus exhibit higher alkalinity. Results indicate that there is a regulatory mechanism between lysosomal oxidative activity and pH. Activation of lysosomal Nicotinamide Adenine Dinucleotide Phosphate (NADPH) oxidase by phorbol ester may result in increase of intralysosomal O2•- and H2O2, concurrent with pH elevation due to consumption of H+ and generation of OH-. Furthermore, the effect of phorbol ester on elevated oxidative activity and pH is heterogeneous among total lysosomal population. Higher oxidative activity and/or pH are only observed in subsets of lysosomes.
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影响因子：
5
作者：
Bach, G;Chen, CS;Pagano, RE
通讯作者：
Pagano, RE
影响因子：
2.2
作者：
RYAN, TC;WEIL, GJ;SIMONS, ER
通讯作者：
SIMONS, ER
影响因子：
4
作者：
Storrie, Brian;Desjardins, Michel
通讯作者：
Desjardins, Michel
DOI：
10.1007/bf02915141
发表时间：
1993-12-01
期刊：
VIRCHOWS ARCHIV B-CELL PATHOLOGY INCLUDING MOLECULAR PATHOLOGY
影响因子：
--
作者：
ZDOLSEK, JM;SVENSSON, I
通讯作者：
SVENSSON, I
影响因子：
9.8
作者：
Aviram, M;Rosenblat, M;Levy, R
通讯作者：
Levy, R