Abstract 3596: Short-term effect of nose-only cigarette smoke exposure on redox homeostasis and mitochondrial metabolism in mice.

Abstract

Abstract The components of cigarette smoke have been implicated in the development of cancer as well as in cardiovascular diseases. We have previously reported oxidative stress in rat tissues induced by tobacco-specific toxins nicotine and 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Recently, we have also shown increased oxidative stress and associated inflammatory responses in various tissues after exposure to cigarette smoke. In this study, we have further investigated the effects of nose-only cigarette smoke exposure on mitochondrial functions and glutathione-dependent redox metabolism in tissues of BALB/C mice. Liver, kidney, heart and lung tissues were analyzed for oxidative stress, glutathione (GSH) and cytochrome P450 dependent enzyme activities and mitochondrial functions after exposure to smoke generated by 9 cigarettes/day for 4 days. Control mice were exposed to air only. An increase in oxidative stress as observed by an increased production of reactive oxygen species (ROS) and altered GSH metabolism was apparent in all the tissues, but lung and heart appeared to be the main targets affected. Increased expression and activity of CYP450 1A1 and 1A2 were also observed in the tissues after exposure to cigarette smoke. Mitochondrial respiratory functions in the tissues, as observed by alterations in the activities of Complex I and IV enzymes, was also observed after exposure to cigarette smoke when compared with air only exposed mice. SDS-PAGE and Western blot results also indicate that alterations in the expression of enzyme proteins were in accordance with the changes in their catalytic functions. These results suggest that even short term exposure of cigarette smoke have adverse effects on mitochondrial functions and redox homeostasis in tissues which may progress to further complications associated with chronic smoking. (The study is supported by Terry Fox Cancer Research Funds and by the Research Committee Grants from College of Medicine and Health Sciences) Citation Format: Haider Raza, Annie John, Abderrahim Nemmar. Short-term effect of nose-only cigarette smoke exposure on redox homeostasis and mitochondrial metabolism in mice. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3596. doi:10.1158/1538-7445.AM2013-3596