Effect of a Polymeric Surfactant on Electron Transport in HL-60 Cells

doi:10.1006/abbi.2000.2104

Archives of Biochemistry and Biophysics

Volume 384, Issue 1, 1 December 2000, Pages 100-108

https://doi.org/10.1006/abbi.2000.2104 Get rights and content

Abstract

To assess the effect of a polymeric surfactant, Pluronic P-105 on the activity of electron transport chains in the mitochondria of HL-60 cells, the bioreduction rates of two membrane-localized lipophilic spin probes, 16-doxylstearic acid methyl ester (16-DSME) and 5-doxylstearic acid (5-DS), were studied. In addition, the effect of Pluronic on the bioreduction rate of the DNA-intercalating spin-labeled anthracyclin drug, Ruboxyl (Rb) was evaluated. For 16-DSME, the bioreduction kinetics was zero order with regard to the nitroxide concentration, indicating that the rate was controlled by the concentration of the reducing enzyme(s), which depends on the activity of the electron transport chains. The introduction of Pluronic at concentrations higher than 0.01% resulted in the decrease of the 16-DSME bioreduction rate. The data suggested that short-term cell incubation with Pluronic resulted in reduced activity of the electron transport chains in the mitochondria of HL-60 cells. This was corroborated by the results of an MTT assay. For 5-DS, the bioreduction kinetics was first order in the absence of Pluronic, but did not follow any simple kinetic law after a short-term cell incubation with Pluronic. For Rb, the degree of nitroxide bioreduction dropped progressively with increasing Pluronic concentration. Thus, incubating cells with polymeric surfactants modulates the intracellular energy metabolism, which can affect the rates of energy-dependent intracellular processes.

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^☆: This work was supported by NIH Grant R01 CA76562-01A1.

²: To whom correspondence and reprint requests should be addressed. Fax: (801) 585-5151. E-mail: [email protected].

³: Current address: Institute of Experimental Cardiology, Russian Academy of Sciences, Moscow, Russia.

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Regular ArticleEffect of a Polymeric Surfactant on Electron Transport in HL-60 Cells☆

Abstract

Colloids Surfaces A: Physicochem. Eng. Aspects

J. Colloid Interface Sci.

Colloids Surfaces B: Biointerfaces

J. Control. Release

Colloids Surfaces B: Biointerfaces

Biochim. Biophys. Acta

Biochim. Biophys. Acta

J. Magn. Res.

J. Immunol. Methods

Biochim. Biophys. Acta

J. Pharmaceut. Sci.

Regular Article
Effect of a Polymeric Surfactant on Electron Transport in HL-60 Cells☆