Role Of Milkvetch Root, Savia Miltiorrhiza And Selenite In Protection Against Nano Titanium Oxide-induced Cell Damage

While nanotechnology has brought huge economic and social benefits to human, ithas also posed great threats to the environment and the organism itself, which explains theimportance and value of reducing the biotoxicity. Via researching the paroxysmmechanism of pneumoconiosis, this paper establishes a vitro model by addingnanometer-scale TiO₂to treat HepG2cells, intervene the process by Milkvetch Root,Savia miltiorrhiza and Sodium Selenite. By observing the treatment results and analysingthe mechanism, this paper draws key conclusions as follow:1. The toxic effect of nano TiO₂of different concentration on the survival of HepG2was assessed by MTT assay. The results showed that the dust of TiO₂can significantlysuppress the cell growth. Cell viability was decreased to58.8%（P<0.01） of the normalcontrol under the treatment of0.25g/L TiO₂, and the viability was decreasing with the increasingof concentration of nano TiO₂.2. By MTT assay, this paper figures out the most appropriate concentrations for thedrugs under a certain concentration of nano TiO₂,It is found that the three drugs,Milkvetch Root, Savia miltiorrhiza and Sodium Selenite （under100nmol/L） can allprotect the decrease of the cell viability. As the drug concentration increased, the cellviabilities increased. The results indicates that those drugs play an protective role in thedevelopment of Pneumoconiosis, and the best ingredient in this research is1000mg/mLfor Milkvetch Root,750mg/mL for Savia miltiorrhiza and100nmol/L for SodiumSelenite.3. Preliminarily investigated the mechanism of reducing the injury caused bynano TiO₂under single component and multicomponent intervence in terms ofantioxidizability. The result showed that the apoptotic body, intracellular ROS, MDA andNO and iNOS levels reduced significantly（P<0.01） after the medicine intervence;multicomponent is more effective than single component（P<0.01）and the activities ofSOD and GPx increased prominently; compared with the single component of the sameconcentration, the activities are also relatively higher; there was no conflicting effect when the three drugs were used together. Those results also indicated that nano TiO₂initiatescell apoptosis by oxidative stress, which led to low cell survival, and the ingredient ofMilkvetch Roo, Savia miltiorrhiza and Sodium Selenite can reduce the harm which nanoTiO₂cast to cells by promoting the oxidation resistance.Those conclusions are preliminary, but they provide beneficial enlightenments toreduce the damage of nano dust, especially, by traditional Chinese medicine of medicinefood homology and trace element Selenium.