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bioRxiv · 10.1101/2021.02.18.431888

Platinum nanoparticles inhibit intracellular ROS generation and protect against Cold Atmospheric Plasma-induced cytotoxicity

Gunes, S.·He, Z.·Malone, R.·Cullen, P. J.·Curtin, J. F.
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Abstract

Platinum nanoparticles (PtNPs) have been investigated for their antioxidant abilities in a range of biological and other applications. The ability to reduce off-target CAP cytotoxicity would be useful in Plasma Medicine, however, little has been published to date about the ability of PtNPs to reduce or inhibit the effects of CAP. Here we investigate whether PtNPs can protect against CAP-induced cytotoxicity in cancerous and non-cancerous cell lines. PtNPs were shown to dramatically reduce intracellular reactive species (RONS) production in human U-251 MG cells. However, RONS generation was unaffected by PtNPs in medium without cells. PtNPs protect against CAP induced mitochondrial membrane depolarization, but not cell membrane permeabilization which is a CAP-induced RONS-independent event. PtNPs act as potent intracellular scavengers of reactive species and can protect both cancerous U-251 MG cells and non-cancerous HEK293 cells against CAP induced cytotoxicity. PtNPs may be useful as a catalytic antioxidant for healthy tissue and for protecting against CAP-induced tissue damage. Graphical AbstractPtNPs are potent catalase and superoxide dismutase mimetics which makes them strong antioxidant candidates for the protection of cells against oxidative stress. CAP was generated using a Dielectric Barrier Device (DBD) system with a voltage output of 75 kV at a frequency of 50 Hz. A range of concentrations of 3nm uncoated PtNPs combined with CAP were examined in human U-251 MG Glioblastoma (GBM) cells and non-cancerous human embryonic kidney HEK293 cells. The protective effects of PtNPs against CAP were explored using several biochemical indicators of oxidative stress and cytotoxicity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/431888v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@128a9f9org.highwire.dtl.DTLVardef@af1f21org.highwire.dtl.DTLVardef@124d6dborg.highwire.dtl.DTLVardef@196040c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Gunes, S., He, Z., Malone, R., Cullen, P. J., Curtin, J. F.. 2021-02-18. Platinum nanoparticles inhibit intracellular ROS generation and protect against Cold Atmospheric Plasma-induced cytotoxicity. https://doi.org/10.1101/2021.02.18.431888

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