| Abstract: |
Cigarette smoking is a pervasive personal habit that is highly addictive (Fayed, 1990). With strong appeal among teenagers and young adult, since the number of young smokers is increasing steadily worldwide (Rubes et al.,1998).Tobacco smoking may induce its dependence through mechanisms involving opiate receptors and peptides (Fayed, 1990).Cigarette smoking is associated with increase incidence and severity of many diseases e.g. chronic obstructive lung disease, bronchogenic carcinoma, atherosclerosis...etc. (Traber et al., 2000).In 1996, Miller reported that air pollution, alcohol, cigarette smoking, non-ionizing irradiation, and psychological stress seem to increase oxidative stress.Morrow in 1995, stated that smoking leads to oxidative stress by multiple mechanism including aqueous extract of cigarette smoke that contain stable oxidant which oxidize human plasma protein. Secondly the gas phase of smoke contain unstable reactive oxygen species such as superoxide (O2•) and Hydrogen peroxide(H2O2).On the other hand the interaction between oxygen free radicals (O2•/H2O2/OH•) of the gas phase and some component of the tar phase produce stable oxidant during burning of tobacco (Panda et al., 1999).A free radical is defined as a molecular species capable of independent existence and contains one or more unpaired electron, such molecules are generally highly reactive (Ward and Peters, 1995) which through their interaction with lipids, proteins, carbohydrates and DNA producecellular damage (Rowe, 1992).
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