Silica nanoparticles-induced cytotoxicity and genotoxicity in A549 cell lines

Among the myriad of nanoparticles, silica nanoparticles (SiO₂NPs) have gained significant attention since they are extensively produced and used across several kinds of industries. Because of its widespread usage, there has been increasing concern about the potential health effects. This study aims to evaluate the effects of SiO₂NPs on Interleukin-6 (IL-6) gene expression in human lung epithelial cell lines (A549). In this study, A549 cells were exposed to SiO₂NPs at concentrations of 0, 1, 10, 50, 100, and 200 µg/mL for 24 and 48 h. The IL-6 gene expression was assessed using Real-Time RT-PCR. Additionally, the impact of SiO₂NPs on the viability of A549 cells was determined by MTT assay. Statistical analysis was performed using GraphPad Prism software 8.0. MTT assay results indicated a concentration-dependent impact on cell survival. After 24 h, survival decreased from 80 to 68% (1-100 µg/mL), rising to 77% at higher concentrations. After 48 h, survival dropped from 97 to 80%, decreasing to 90% at higher concentrations. RT-PCR showed a dose-response relationship in cellular toxicity up to 10 µg/mL. At higher concentrations, there was increased IL-6 gene expression, mitigating SiO₂NP-induced cytotoxic effects. The study shows that the viability and proliferation of A549 cells are impacted by different SiO₂NPs concentrations. There may be a potential correlation between IL-6 gene expression reduction and a mechanism linked to cellular toxicity. However, at higher concentrations, an unknown mechanism increases IL-6 gene expression, reducing SiO₂NPs' cytotoxic effects. These effects are concentration-dependent and not influenced by exposure times. Further investigation is recommended to determine this mechanism's nature and implications, particularly in cancer research.