P-benzosemiquinone of cigarette smokecauses protein modification apotosis and emphysematous leung damage; prevention by activated charged filter

摘要

We had indicated before that p-benzosemiquinone (p-BSQ), a major highly reactive harmful long-lived radical occurring in high concentrations in cigarette smoke, is responsible for proteins and DNA damage, leading to various degenerative diseases (US Patent No. 6929012, dated August, 2005). In the said patent we described the process of isolation, identification, general properties and assay of p- benzosemiquinone (p-BSQ) from an Indian commercial cigarette. Here we present data to show that, besides the Indian commercial cigarette, p-BSQ is present in the smoke from a variety of international cigarettes. We had also indicated that p-BSQ content in the smoke might be a parameter of toxicity of a particular brand of cigarette and that elimination of p-BSQ from the mainstream smoke would produce potentially less hazardous safer cigarettes. Accordingly, we had devised activated charcoal filter for effectively reducing p-BSQ from the mainstream smoke of an Indian commercial cigarette (US Patent No. 7,025,067 B2). Here we further show that the charcoal filter also effectively reduces p-BSQ from the smoke of a variety of international brands of cigarettes examined. Since different international brands of cigarettes are made from different blends of tobacco, our findings indicate that our charcoal filter effectively reduces p-BSQ from different blends of tobacco. It is well known that the most important cause of pulmonary emphysema is cigarette smoking, which is preceded by protein modification and apoptosis. Here we demonstrate that p- BSQ mimics CS in causing protein modification and apoptosis in vitro and ex vivo in cultured human lung epithelial cells (A549). Using a guinea model, here we further demonstrate that p-BSQ of cigarette smoke causes apoptosis of alveolar cells and pulmonary emphysema in vivo and that by reducing p-BSQ from the mainstream smoke, the charcoal filter prevents cigarette smoke-induced apoptosis and emphysema in guinea pigs in vivo. Since activated charcoal filter is also known to absorb many of the toxic components of cigarette smoke, the said activated charcoal filter is expected to prevent cigarette smoke-induced cardiovascular diseases and cancer and thereby producing less hazardous safer cigarettes.