BAT - Inextricably Twinned With Reduced Risk Research

Source from:  Tobacco Reporter 11/19/2010

British American Tobacco says a study of twins has revealed markers of biological effects that could form the basis of a database useful in assessing new products designed to reduce risk. "Studies of adult identical twins could provide valuable tools in the effort to reduce the harm associated with smoking," the company said in a recent press note. "Our study of Italian twins revealed 10 biomarkers of biological effect that might be of assistance in predicting smoking-related risk. These biomarkers could form the basis of a database of biomarkers that could be used to assess any new products designed to be reduced risk." "The development of 'safer' tobacco products is the 'Holy Grail' of tobacco research. But in order to be able to demonstrate reduced risk for one or more smoking-related diseases, scientists must have tools to objectively assess prototype tobacco products against conventional cigarettes." "This is why scientists at British American Tobacco are working to identify biomarkers of biological effect that might help indicate whether the use of a new tobacco product is likely to reduce the risks. For many of these biomarkers, however, genetics are likely to play a role, which is where identical twins come in." "By studying monozygotic twin pairs, genetic variability has been excluded as a possible source of variability in this study and these results should assist the interpretation of other population studies using these biomarkers," explained Dr. Chris Proctor, chief scientific officer at BAT. "A clearer pattern of the effects of lifestyle and environment should also become more apparent," he said. BAT said that it was undertaking several studies to try to identify biomarkers of biological effect that might be of assistance in predicting smoking-related risk. The current study, which is being published in the January issue of the journal, Clinical Chemistry and Laboratory Medicine, involved 24 pairs of identical twins discordant for smoking and examined 30 biomarkers of biological effect and physiological status, as well as biomarkers of exposure to nicotine, carbon monoxide and a tobacco-specific nitrosamine found in tobacco smoke. "As expected, biomarkers indicating exposure to tobacco were elevated in smokers," the press note said. "In addition, there were 10 markers of biological effect found to be significantly elevated in smokers. There was no correlation between smoking status and lipid levels." "The twin pairs were aged between 23 and 46 years, and in each case, one twin did not smoke, and the other did, on average between 13 and14 cigarettes a day. The twin pairs were observed for several days, during which time their eating, drinking and smoking habits were recorded, and blood and urine samples were taken regularly. All biomarkers indicating exposure to tobacco were elevated in smokers, and there were statistically significant elevations in smokers in: 11-dehydrothromboxane B2, 2,3-dinorthromboxane B2; 8-epi-prostaglandin F2α; hydroxyproline and fibrinogen concentrations; exhaled carbon monoxide; total white blood cell, neutrophil and lymphocyte counts; and in heart rate and a shortening of the coronary PT interval. A number of these markers are reported as being associated with inflammatory conditions and possible early stages of vascular disorders." "There was no correlation between smoking status and lipid levels, which are often used as a marker of cardiovascular risk. There was also no statistically significant difference between smokers and non-smokers in the levels of 8-OHdG and cTG, both of which are thought to be indicators of oxidative DNA damage and the initiation of carcinogenic processes." Enditem