Document Type

Article

Publication Date

5-2020

Publication Title

International Journal of Molecular Sciences

Volume

21

Issue

9

Pages

3386 (17 pp.)

DOI

10.3390/ijms21093386

Abstract

The principal bioeffect of the nanosecond pulsed electric field (nsPEF) is a lasting cell membrane permeabilization, which is often attributed to the formation of nanometer-sized pores. Such pores may be too small for detection by the uptake of fluorescent dyes. We tested if Ca2+, Cd2+, Zn2+, and Ba2+ ions can be used as nanoporation markers. Time-lapse imaging was performed in CHO, BPAE, and HEK cells loaded with Fluo-4, Calbryte, or Fluo-8 dyes. Ca2+ and Ba2+ did not change fluorescence in intact cells, whereas their entry after nsPEF increased fluorescence within <1 ms. The threshold for one 300-ns pulse was at 1.5–2 kV/cm, much lower than >7 kV/cm for the formation of larger pores that admitted YO-PRO-1, TO-PRO-3, or propidium dye into the cells. Ba2+ entry caused a gradual emission rise, which reached a stable level in 2 min or, with more intense nsPEF, kept rising steadily for at least 30 min. Ca2+ entry could elicit calcium-induced calcium release (CICR) followed by Ca2+ removal from the cytosol, which markedly affected the time course, polarity, amplitude, and the dose-dependence of fluorescence change. Both Ca2+ and Ba2+ proved as sensitive nanoporation markers, with Ba2+ being more reliable for monitoring membrane damage and resealing.

Comments

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.

Original Publication Citation

Bo, W., Silkunas, M., Mangalanathan, U., Novickij, V., Casciola, M., Semenov, I., ... & Pakhomov, A. G. (2020). Probing nanoelectroporation and resealing of the cell membrane by the entry of Ca2+ and Ba2+ Ions. International Journal of Molecular Sciences, 21(9), 3386. doi: 10.3390/ijms21093386

ORCID

0000-0003-4017-8260 (Bo), 0000-0003-0203-0847 (Casciola), 0000-0002-0302-1355 (Semenov), 0000-0003-4950-4130 Pakhomova), 0000-0003-3816-3860 (Pakhomov)

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