TY - JOUR
T1 - Dietary fiber decreases colonic epithelial cell proliferation and protein synthetic rates in human subjects
AU - Weerasooriya, Viraine
AU - Rennie, Michael J.
AU - Anant, Shri
AU - Alpers, David H.
AU - Patterson, Bruce W.
AU - Klein, Samuel
PY - 2006
Y1 - 2006
N2 - Although it has been proposed that high fiber consumption can prevent proliferative diseases of the colon, the clinical data to support this hypothesis have been inconsistent. To provide a more robust measure of the effects of fiber on colonic mucosal growth than previous studies, we evaluated both cell proliferation and colonic mucosal protein synthesis in nine healthy volunteers after they consumed a typical Western diet (<20 g fiber/day) or a Western diet supplemented with wheat bran (24 g/day) in a randomized crossover design. Biopsies taken from the sigmoid colon were used to assess mucosal proliferation by determining proliferating cell nuclear antigen (PCNA) in crypt cells and to assess mucosal protein synthetic rate using stable isotopically labeled leucine infusion. Fiber supplementation produced a 12% decrease in labeling index (%crypt cells stained with PCNA) (P < 0.001) and an 11% decrease in mucosal protein fractional synthetic rate (FSR; P < 0.05). Moreover, mucosal protein FSR correlated directly with labeling index (r 2 = 0.22, P < 0.05). These data demonstrate that increased wheat bran consumption decreases colonic mucosal proliferation and support the potential importance of dietary fiber in preventing proliferative diseases of the colon.
AB - Although it has been proposed that high fiber consumption can prevent proliferative diseases of the colon, the clinical data to support this hypothesis have been inconsistent. To provide a more robust measure of the effects of fiber on colonic mucosal growth than previous studies, we evaluated both cell proliferation and colonic mucosal protein synthesis in nine healthy volunteers after they consumed a typical Western diet (<20 g fiber/day) or a Western diet supplemented with wheat bran (24 g/day) in a randomized crossover design. Biopsies taken from the sigmoid colon were used to assess mucosal proliferation by determining proliferating cell nuclear antigen (PCNA) in crypt cells and to assess mucosal protein synthetic rate using stable isotopically labeled leucine infusion. Fiber supplementation produced a 12% decrease in labeling index (%crypt cells stained with PCNA) (P < 0.001) and an 11% decrease in mucosal protein fractional synthetic rate (FSR; P < 0.05). Moreover, mucosal protein FSR correlated directly with labeling index (r 2 = 0.22, P < 0.05). These data demonstrate that increased wheat bran consumption decreases colonic mucosal proliferation and support the potential importance of dietary fiber in preventing proliferative diseases of the colon.
KW - Cancer
KW - Metabolism
KW - Short-chain fatty acids
UR - http://www.scopus.com/inward/record.url?scp=33744920304&partnerID=8YFLogxK
U2 - 10.1152/ajpendo.00557.2005
DO - 10.1152/ajpendo.00557.2005
M3 - Article
C2 - 16682486
AN - SCOPUS:33744920304
SN - 0193-1849
VL - 290
SP - E1104-E1108
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 6
ER -