It is now evident that oxidant/antioxidant balance is altered in favor of oxidants in smokers, which play an important role in the pathogenesis of COPD. Therefore, it would be logical to propose the rationale of antioxidant therapy in ameliorating the increased inflammatory response in COPD. Furthermore, proof of concept of the role of oxidative stress in the pathogenesis of COPD will come from studies of effective antioxidant therapy. There are various options to enhance the lung anti-oxidant screen. One approach would be to use specific spin traps such as a-phenyl-N-tert-butyl nitrone to react directly with reactive oxygen and reactive nitrogen species at the site of inflammation (222). The therapeutic purposes of this drug are currently in clinical development. Inhibitors that have a double action, such as the inhibition of lipid peroxidation and quenching radicals, could be developed. Another approach could be the molecular manipulation of antioxidant genes, such as glutathione peroxidase or genes involved in the synthesis of glutathione, such as y-GCS or by developing molecules with an activity similar to these antioxidant enzymes.
Recent animal studies have shown that recombinant SOD treatment can prevent the neutrophil influx to the airspaces and IL-8 release induced by cigarette smoking through a mechanism involving downregulation of NF-kB (223). This holds great promise if compounds can be developed with anti-oxidant enzyme properties, which may be able to act as novel anti-inflammatory drugs by regulating the molecular events in lung inflammation.
Another approach would simply be to administer antiox-idant therapy. This has been attempted in cigarette smokers using various antioxidants such as vitamin C and vitamin E (224,225). The results have been rather disappointing, although as described above the antioxidant vitamin E has been shown to reduce oxidative stress in patients with COPD (226).
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Save Your Lungs And Never Have To Spend A Single Cent Of Ciggies Ever Again. According to a recent report from the U.S. government. Centers for Disease Control and Prevention, more than twenty percent of male and female adults in the U.S. smoke cigarettes, while more than eighty percent of them light up a cigarette daily.