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Belosludtsev KN, Belosludtseva NV, Agafonov AV, Penkov NV, Samartsev VN, Lemasters JJ, Mironova GD. Effect of surface-potential modulators on the opening of lipid pores in liposomal and mitochondrial inner membranes induced by palmitate and calcium ions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2200-5. [PMID: 26014488 DOI: 10.1016/j.bbamem.2015.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 05/16/2015] [Accepted: 05/18/2015] [Indexed: 02/08/2023]
Abstract
The effect of surface-potential modulators on palmitate/Ca2+-induced formation of lipid pores was studied in liposomal and inner mitochondrial membranes. Pore formation was monitored by sulforhodamine B release from liposomes and swelling of mitochondria. ζ-potential in liposomes was determined from electrophoretic mobility. Replacement of sucrose as the osmotic agent with KCl decreased negative ζ-potential in liposomes and increased resistance of both mitochondria and liposomes to the pore inducers, palmitic acid, and Ca2+. Micromolar Mg2+ also inhibited palmitate/Ca2+-induced permeabilization of liposomes. The rate of palmitate/Ca2+-induced, cyclosporin A-insensitive swelling of mitochondria increased 22% upon increasing pH from 7.0 to 7.8. At below the critical micelle concentration, the cationic detergent cetyltrimethylammonium bromide (10 μM) and the anionic surfactant sodium dodecylsulfate (10-50 μM) made the ζ-potential less and more negative, respectively, and inhibited and stimulated opening of mitochondrial palmitate/Ca2+-induced lipid pores. Taken together, the findings indicate that surface potential regulates palmitate/Ca2+-induced lipid pore opening.
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Affiliation(s)
- Konstantin N Belosludtsev
- Institute of Theoretical and Experimental Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia.
| | - Natalia V Belosludtseva
- Institute of Theoretical and Experimental Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia
| | - Alexey V Agafonov
- Institute of Theoretical and Experimental Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia
| | - Nikita V Penkov
- Institute of Cell Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia
| | - Victor N Samartsev
- Mari State University, pr. Lenina 1, Yoshkar-Ola, Mari El 424001, Russia
| | - John J Lemasters
- Institute of Theoretical and Experimental Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia; Center for Cell Death, Injury & Regeneration, Departments of Drug Discovery & Biomedical Sciences and Biochemistry & Molecular Biology , Medical University of South Carolina, DD504 Drug Discovery Building, 70 President Street, MSC 140, Charleston, SC 29425, USA
| | - Galina D Mironova
- Institute of Theoretical and Experimental Biophysics RAS, Institutskaya 3, Pushchino, Moscow region 142290, Russia
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