Arabinoxylan-oligosaccharides (AXOS) reduce preneoplastic lesions in the colon of rats treated with 1,2-dimethylhydrazine (DMH)

Abstract

BackgroundPrebiotics are non-digestible compounds that beneficially affect the host by stimulating the growth and/or activity of one
or a limited number of resident colonic bacteria in the gut. Reported beneficial effects of prebiotics include reduced gut
infections, better absorption of minerals, and notably, antitumorigenic effects. Arabinoxylan (AX)-oligosaccharides (AXOS)
have been suggested to exert prebiotic effects in the gut, but their effect on colon carcinogenesis has not been studied so
far.

Aim of the studyTo test the effect of AXOS in a rat colon carcinogenesis model.

MethodsWe determined the occurrence of two types of preneoplastic lesions [aberrant crypt foci (ACF) and mucin depleted foci (MDF)]
in the colon of rats treated with the colon carcinogen 1,2-dimethylhydrazine (DMH) and fed either a control diet or a diet
containing AXOS (4.8% w/w) (15 rats in each group).

ResultsThirteen weeks after DMH treatment, MDF counts were significantly lower in the entire colon of AXOS fed rats (MDF/colon were
7.5±0.6 and 5.5±0.6, in Control and AXOS groups, respectively, means±SE, P<0.05). Although the number of ACF in the entire colon was not significantly different between Control and AXOS fed rats,
AXOS fed rats had significantly fewer ACF in the distal part of the colon than Control group rats (ACF/distal colon were 135.5±15
and 84.4±11, in Control and AXOS groups, respectively, means±SE, P<0.05).

ConclusionsThe present study shows that dietary intake of AXOS by rats reduces the occurrence of two types of preneoplastic lesions,
thus suggesting a chemopreventive effect on colon carcinogenesis that should be confirmed in a long-term carcinogenesis experiment.