title: Pro-oxidant environment of the colon compared to the small intestine may contribute to greater cancer susceptibility.
abstract: The colon and small intestine have inherent differences (e.g. redox status) that may explain the variation in cancer occurrence at these two sites. This study examined basal and induced (oxidative challenge) reactive oxygen species (ROS) generation, antioxidant enzyme activity and oxidative DNA damage. Basal ROS and antioxidant enzyme activities in the colon were greater than in the small intestine. During oxidative stress, 8-oxo-deoxyguanosine (8-oxodG) DNA adducts in the colon exceeded levels in the small intestine concomitant with increased ROS. Thus the colon responds to oxidative stress less effectively than the small intestine, possibly contributing to increased cancer incidence at this site.
authors.affiliation: Faculty of Nutrition, Texas A & M University, 2471 TAMU, College Station, TX 77843-2471, USA.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Sanders
authors.forename: Cara E
authors.initials: CE
authors.lastname: Henderson
authors.forename: Mee Young
authors.initials: MY
authors.lastname: Hong
authors.forename: Rola
authors.initials: R
authors.lastname: Barhoumi
authors.forename: Robert C
authors.initials: RC
authors.lastname: Burghardt
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Carroll
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Turner
authors.forename: Robert S
authors.initials: RS
authors.lastname: Chapkin
authors.forename: Joanne R
authors.initials: JR
authors.lastname: Lupton
mesh_terms: D000818:Animals; D002374:Catalase / Q000378:metabolism; D003106:Colon / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000209:etiology*; D004249:DNA Damage; D004198:Disease Susceptibility; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species
chemical_list: D017382:Reactive Oxygen Species; D002374:Catalase