Photoexcited fullerene C₆₀ disturbs prooxidant‐antioxidant balance in leukemic L1210 cells

Abstract

According to the data of laser‐correlation spectroscopy of the pristine fullerene C60 water colloid solution used in the study the average hydrodynamic radius of nanoparticles was 50 nm and no agglomeration was observed. With the use of the fluorescent probe 2′,7′‐dichlorofluorescein the production of reactive oxygen species (ROS) in rat thymocytes and in human leukemic cells L1210 pretreated with 10–5 M fullerene C60 and irradiated in a diapason 320–600 nm was estimated. Irradiation per se is shown to be followed by slight increase of ROS production. No further increase of fluorescent signal was detected in thymocytes during 3 h of incubation after combined action of C60 and irradiation. In contrast leukemic cells respond to combined action of C60 and irradiation by pronounced intensification of ROS production. This phenomenon is shown to be connected with prooxidant‐antioxidant imbalance induced by photoexcited fullerene C60 in L1210 cells, enhancement of the first superoxide dismutase against decreasing of the second glutathione peroxidase steps of antioxidant defense. The prooxidant effect of photoexcited fullerene C60 leading to oxidative stress could be used for elaborating the strategies of targeted oxidative injury of leukemic cells.

Structural Features of Highly Stable Reproducible C60Fullerene Aqueous Colloid Solution Probed by Various Techniques

“…N u m ero u s experim ental investi gations have dem onstrated the polydisperse n atu re o f C 60FA S, including either m onom ers or aggregates having diam eters ranging from several to hundreds o f nanom eters (26,28,29), w hich fully agrees w ith our A F M /S T M results presented above. correlation spectroscopy o f pristine C 60 fullerene w ater col loid solution, w hich confirm th a t the average hydrodynam ic radius o f nanoparticles is 50 nm and no further agglom era tion is observed (31).…”

Activation of store – operated Ca(2+) entry in cisplatin resistant leukemic cells after treatment with photoexcited fullerene C(60) and cisplatin

“…As it was previously shown, photoexcitation of fullerene C 60 accumulated by human lymphoma Jurkat cells was also accompanied by enhancement of SOCE and cell death by apoptosis [27]. We assume that the observed enhancement of SOCE in leukemic cells of both lines could be mediated in part by intense ROS production after fullerene C 60 photoexcitation [28]. Prevoius studies have revealed a cross-talk between ROS and components of Ca 2+regulating system [29].…”

Fullerene C60 Penetration into Leukemic Cells and Its Photoinduced Cytotoxic Effects

“…Considering the fact that our previous study has demonstrated substantial increase of ROS production in L1210 cells after pristine fullerene C 60 photoexcitation in UV/Vis spectrum [41], we suggested that C 60 interaction with mitochondrial membranes and ROS generation after its photoexcitation are followed by essential uncoupling of electron-transporting chain components, proton leak across inner mitochondrial membrane, and Δψ drop.…”