Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2
Al-Khedhairy, Javed Ahmad · Maqusood Ahamed · Mohd Javed Akhtar ·Salman A Alrokayan · Maqsood A Siddiqui · Javed Musarrat ·Abdulaziz A . 2012
Abstract
Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 μg/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion of glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level.
Background: Nanotechnology and material science have developed enormously fast in recent years. Due to their excellent magnetic properties, iron oxide nanoparticles (IONPs) have been broadly…
Background: Colorectal cancer (CRC) is the third most diagnosed cancer in the world. Artemisia monosperma (family: Asteraceae), a flowering plant species in the genus Artemisia, is widely used in…
Vanadium oxide is largely applied as a chemical and industrial product in various field such as in electro- chemical, photochemical and refining industries. Very limited studies are available for…