Xue Zhou
Huazhong University of Science and Technology, China
Title: Cytotoxicity of calcium rectorite micro/nanoparticles before and after organic modification
Biography
Biography: Xue Zhou
Abstract
Organically modified rectorite (OREC) micro/nanoparticles can be synthesized by organic modification from calcium rectorite (Ca2+-REC or REC), a common form of rectorite in nature. Although REC and OREC have potential applications in food packing and drug delivery, their cytotoxicity is not clear. In the present study, we investigated and compared the cytotoxicity of REC and OREC micro/nanoparticles in Chang liver and HepG2 cells. The interlayer spacing of OREC was enlarged after organic modification. REC and OREC could be taken up by Chang liver cells after treatment. REC and OREC induced cytotoxicity in Chang liver and HepG2 cells at almost all doses (1, 2.5, 5, 7.5, and 10μg/mL) after 6, 24, and 48 h of treatment (P<0.05 or P<0.01). OREC was more cytotoxic than REC. However, there was no difference in the cytotoxicity of REC and OREC between the two cell lines. After treatment with REC or OREC at 7.5 and 10μg/mL for 24 h, the apoptotic and necrotic percentages of Chang liver cells were increased (P<0.05 or P<0.01). The levels of apoptosis-related proteins Bax, Bcl-2, and pro-caspase-3 were all decreased in Chang liver cells after 24h of exposure to REC or OREC at 5, 7.5 and 10μg/mL. There was no change in Bax/Bcl-2 ratio after treatment, indicating that REC or OREC-induced apoptosis was not associated with Bax-related mitochondria-mediated apoptotic pathway. Our results suggested that OREC was more cytotoxic than REC, but the underlying mechanisms need further investigation.