A number of chemicals have been established as causes for the premature deaths
of smokers. Carbon monoxide is by far the most
deadly: not because of its direct action of tying up hemoglobin (which in excess
causes death by asphyxiation), but because it is a reactive oxidizing agent that causes a healing response in artery
walls which results in arteriosclerosis. Heart attacks are responsible for more
early deaths among smokers, due to carnary artery disease, than cancer. A major study found that in any given year for
the group of pack-a-day + smokers age 40 to 79, they were 2.09 times more like to die of a heart attack than the control group
of non-smokers. This translated into 2.74 times more deaths from coronary than from cancer. (TABACCO SMOKE: its statistical consequences). The tars in tobacco smoke that accumulate in the lungs contain a number of
carcinogens. The normally pink lungs turn black, which after viewing makes one wonder why the percentage of smokers
who get lung cancer isn't higher. Polonium 210, a radioactive isotope (similar to lead) is found in a minute amount;
however over a period of 20 years for a pack a day smoker, enough accumulates so that it is a major statistical cause
of lung cancer. Another compound is nomicotine which modifies proteins to form
the troublesome glycation endpoducts AGEs)--SEE ARTICLE BELOW.
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October 30, 2002 Proceedings of the National Academy of Sciences
Nicotine By-product 'Cooks' Body's Proteins
In news that could give smokers yet another reason to kick the habit, researchers have
found that a nicotine by-product known as nornicotine modifies the body's proteins in potentially harmful ways. The results
of their study, published online yesterday by the Proceedings of the National Academy of Sciences, indicate that the
chemical may contribute to aging and to the development of a number of diseases.
Specifically, report Tobin J. Dickerson and Kim D. Janda
of the Scripps Research Institute in La Jolla, Calif., nornicotine appears to encourage good proteins to go bad by chemically
"cooking" them. The modified proteins then interact with other chemicals in the body and can form troublesome compounds known
as advanced glycation endproducts (AGEs). "These advanced glycation endproducts are not supposed to be [present in your body]
naturally," Dickerson explains. "Your body is not prepared for them." Indeed, previous work has implicated AGEs in a variety
of diseases, including diabetes, cancer and Alzheimer's.
Importantly, the team
found that smokers had more nornicotine-modified proteins--and more AGEs--in their blood than nonsmokers did. The researchers
also discovered that nornicotine reacts with the commonly prescribed steroids cortisone and prednisone, hinting that it could
compromise drug safety and efficacy. -- Kate
Wong
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