Multi-walled carbon nanotubes induce oxidative stress and apoptosis in human lung cancer cell line-A549.

Abstract

Multi-walled carbon-nanotubes (MWCNTs)-induced apoptotic changes were studied in human lung epithelium cell line-A549. Non-cytotoxic doses of MWCNTs were identified using tetrazolium bromide salt (MTT) and lactate dehydrogenase (LDH) release assays. Cells were exposed to MWCNTs (0.5-100 μg/ml) for 6-72 h. Internalization and characterization of CNTs was performed by electron microscopy. Apoptotic changes were estimated by nuclear condensation, DNA laddering, and confirmed by expression of associated markers: p(53), p(21WAF1/CIP1), Bax, Bcl(2) and activated caspase-3. MWCNTs induced the production of reactive oxygen species and malondialdehyde along with significant decrease in the activity of catalase and glutathione. MWCNTs-induced ROS generation was found not to be associated with the mitochondrial activity. In general, the changes were significant at 10 and 50 μg/ml only. Results indicate the involvement of oxidative stress and apoptosis in A549 cells exposed to MWCNTs. Our studies provide insights of the mechanisms involved in MWCNTs-induced apoptosis at cellular level.

• Authors: Ritesh K Srivastava, Aditya B Pant, Mahendra P Kashyap, Vivek Kumar, Mohathshim Lohani, Ludwig Jonas, Qamar Rahman
• Journal: Nanotoxicology (Nanotoxicology) Vol. 5 Issue 2 Pg. 195-207 (Jun 2011) ISSN: 1743-5404 [Electronic] England
• PMID: 20804439 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Nanotubes, Carbon
• Reactive Oxygen Species
• Uncoupling Agents
• Rotenone

Topics

• Animals
• Apoptosis (drug effects)
• Biomarkers (metabolism)
• Cell Line, Tumor (drug effects)
• Humans
• Lung Neoplasms
• Mitochondria (metabolism)
• Nanotubes, Carbon (adverse effects, ultrastructure)
• Oxidative Stress (drug effects)
• Reactive Oxygen Species (metabolism)
• Rotenone (metabolism)
• Uncoupling Agents (metabolism)