| Autor: |
Ruiz-Saavedra S; Department of Microbiology and Biochemistry of Dairy Products, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), 33300 Villaviciosa, Spain.; Diet, Microbiota and Health Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain., Pietilä TK; Department of Food and Nutrition, University of Helsinki, 00014 Helsinki, Finland., Zapico A; Department of Functional Biology, University of Oviedo, 33006 Oviedo, Spain.; Diet, Microbiota and Health Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain., de Los Reyes-Gavilán CG; Department of Microbiology and Biochemistry of Dairy Products, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), 33300 Villaviciosa, Spain.; Diet, Microbiota and Health Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain., Pajari AM; Department of Food and Nutrition, University of Helsinki, 00014 Helsinki, Finland., González S; Department of Functional Biology, University of Oviedo, 33006 Oviedo, Spain.; Diet, Microbiota and Health Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain. |
| Abstrakt: |
Diet is one of the main exogenous sources of potentially carcinogenic nitrosamines (NAs) along with tobacco and cosmetics. Several factors can affect endogenous N-nitroso compounds (NOCs) formation and therefore the potential damage of the intestinal mucosa at initial colorectal cancer stages. To address this issue, 49 volunteers were recruited and classified according to histopathological analyses. Lifestyle and dietary information were registered after colonoscopy. The mutagenicity of fecal supernatants was assayed by a modified Ames test. Fecal heme-derived NOCs and total NOC concentrations were determined by selective denitrosation and chemiluminescence-based detection. Results revealed processed meats as the main source of dietary nitrites and NAs, identifying some of them as predictors of the fecal concentration of heme-derived and total NOCs. Furthermore, increased fecal NOC concentrations were found as the severity of colonic mucosal damage increased from the control to the adenocarcinoma group, these concentrations being strongly correlated with the intake of the NAs N-nitrosodimethylamine, N-nitrosopiperidine, and N-nitrosopyrrolidine. Higher fecal NOC concentrations were also noted in higher fecal mutagenicity samples. These results could contribute to a better understanding of the importance of modulating dietary derived xenobiotics as related with their impact on the intestinal environment and colonic mucosa damage. |
