Modulation of colonic biomarkers by different types of dietary fat and fiber during tumorigenesis /
Maintenance of a healthy colonic epithelium is a delicate balance between cell birth, differentiation and death, which may be disrupted during the tumorigenic process. The effects of specific types of dietary fats (corn oil and fish oil) and fibers (cellulose and pectin) on cell proliferation, diff...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1997.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739887671&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Maintenance of a healthy colonic epithelium is a delicate balance between cell birth, differentiation and death, which may be disrupted during the tumorigenic process. The effects of specific types of dietary fats (corn oil and fish oil) and fibers (cellulose and pectin) on cell proliferation, differentiation, and apoptosis in rat colon carcinogenesis were examined. The percentage of rats with adenocarcinomas was: corn/cellulose 75.6%; corn/pectin 63.6%; fish/cellulose 60.6%; fish/pectin 51.5%. No tumors were found in saline-injected control rats. In the model of dietary effect on colon tumorigenesis, both lectin DBA binding (differentiation marker) and apoptosis were better predictors of tumor development. Cell proliferation indices could detect the carcinogenic effect of AOM, but not the protective effect of fish oil/pectin. The carcinogenic effect of AOM was best represented by the ratio of cell proliferation vs apoptosis, which was higher in both proximal and distal with P <0.0 1 5 as compared to saline. Fish oil also resulted in a lower ratio of cell proliferation vs apoptosis as compared to corn oil in both proximal (P = 0.0001) and distal (P = 0.0003) colon. The combined effect of fat and fiber was best explained through apoptosis. Fish oil/pectin diet resulted in an increase of number of apoptotic cells per crypt column in both proximal and distal (P < 0.05), and an increase of apoptotic index in the distal colon (P < 0.05) as compared to the other three diets. Fish oil/pectin also resulted in the highest concentration of lumenal butyrate in both proximal and distal colon (P < 0.015). There was a site specific relationship between lumenal butyrate concentration and cell differentiation/apoptosis, which was positive (P < 0.05) in the proximal colon but there was no correlation in the distal colon. These data suggest that dietary fats and fibers may modulate colon carcinogenesis through apoptosis and cell differentiation, in addition to their effect on cell proliferation. |
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| Item Description: | Vita. "Major Subject: Nutrition". |
| Physical Description: | xii, 225 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 127-160. |