Crosstalk Between Co-Cultured 3T3-L1 and C2C12 Cells After the Exposure of Nano-Titanium Dioxide.

Nanotechnology is a promptly growing field in this century, and it have been extensively used in several solicitations. Reactive oxygen species (ROS) generation is one of the important mechanism of action of nanoparticles. The excess ROS generation can induce oxidative stress, so the cells are unable to sustain the normal biological redox-regulated tasks. The high oxidative stress and ROS formation condition, damage the biological macromolecules, cell signaling pathways and finally leads to cell death or cancer initiation. The objective of the present study is to reveal the effects of TiO2 nanoparticle on co-culture system. The cell viability, oxidative stress and apoptosis were evaluated in monolayer and co-culture 3T3-L1 cells after the exposure of TiO2. Our results indicated that TiO2 significantly induces the reactive oxygen species (ROS), lipid peroxidation and decrease in the level of glutathione. Additionally, real-time PCR data analysis shown an increased in the expression of p53, Bax, caspase-9, caspase-3 and decreased the level of Bcl-2, by this means specifying that apoptosis induced by TiO2 NPs occurs via the caspase-dependent pathway. This study analytically shows that oxidative stress is the fundamental mechanism by which TiO2 causes apoptosis in a co-culture system even at very low concentrations. In the future, the use of such nanoparticles should be cautiously scrutinized.