Pro-oxidant environment of the colon compared to the small intestine may contribute to greater cancer susceptibility.
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.
Sanders
Lisa M
LM
Faculty of Nutrition, Texas A & M University, 2471 TAMU, College Station, TX 77843-2471, USA.
Henderson
Cara E
CE
Hong
Mee Young
MY
Barhoumi
Rola
R
Burghardt
Robert C
RC
Carroll
Raymond J
RJ
Turner
Nancy D
ND
Chapkin
Robert S
RS
Lupton
Joanne R
JR
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
D017382:Reactive Oxygen Species; D002374:Catalase