Prebiotics may stop early stage colon cancer: Study

The products of prebiotic fermentation in the gut may prevent the growth, and promote the death of cancer cells in the colon, says a new study from Germany.

When human colon cells representing early and late stages of colon cancer were exposed to short chain fatty acids, which are produced during the fermentation of prebiotic fibres by gut bacteria, the early stage cells “responded more sensitively”, according to findings published in the British Journal of Nutrition.

“Since early [cancer] cells were found to be more sensitive, this may have important implications for chemoprevention when translated to the in vivo situation, because survival of early transformed cells could be reduced,” wrote the researchers, led by Daniel Scharlau from the Institute for Nutrition at the Friedrich-Schiller-University in Jena.

Prebiotics are defined as: “A selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora, that confers benefits upon health wellbeing and health.” (2004)

The German researchers used fermentation products prepared by incubating bacterial samples from faeces with a Beneo Orafti’s Synergy1 prebiotic, which is composed of a mixture of inulin enriched with oligofructose.

Interpret with caution

Commenting on the study, Anke Sentko, VP of regulatory affairs and nutrition communication for the Beneo Group told NutraIngredients that while the study is “an interesting in vitro study it should not be over interpreted”.

“Inulin, fermented in the lower gut, contributes to a healthy gut environment. This study supports this," added Sentko.

The most extensive research to date is with these inulin-type fructans, and the reported health benefits of prebiotics relate to improving bones health, reducing the risk of colorectal cancer, boosting immunity, and enhancing satiety and aiding weight management.

The most extensive research to date is with these inulin-type fructans, and the reported health benefits of prebiotics relate to improving bones health, reducing the risk of colorectal cancer, boosting immunity, and enhancing satiety and aiding weight management.

In terms of colon cancer, numerous animal studies have reported that prebiotic and/or probiotic intake may reduce the risk of developing the disease. The results of the EU-sponsored SynCan project show that the combination of pre- and probiotics (BeneoOrafti's Synergy1 plus Lactobacillus GG and Bifidobacteria) could favourably shift the populations of faecal bacteria, with larger populations of protective bacteria and reduced numbers of cancer-promoting bacteria. (Am. J. Clin. Nutr., 2007, Vol. 85, pp. 488-496).

Study details

Dr Scharlau and his co-workers used two sets of human colon cell lines, one as a model early stage colon cancer and the other as a model of late stage colon cancer. The cells were then exposed to the prebiotic fermentation products, obtained from incubating bacterial samples from faeces with Synergy1, or a synthetic fermentation mixture.

Upon incubation with Synergy1, the researchers noted a 2.5-fold increase in short chain fatty acid levels, and a 3.4-fold decrease in deoxycholic acid (DCA), a bile acid, compared to a control sample.

“In comparison with HT29 cells, LT97 cells responded more sensitively to the growth-inhibitory activities,” wrote the researchers.

Moreover, a significant increase in the action of a protein associated with programmed cell death (apoptosis).

“The present results indicate growth-inhibiting and apoptosis-inducing effects of fermentation supernatant fractions of inulin,” concluded the researchers.

Source: British Journal of Nutrition

September 2009, Volume 102, Issue 05, pp 663-671, doi:10.1017/S0007114509274770

“Fermentation products of inulin-type fructans reduce proliferation and induce apoptosis in human colon tumour cells of different stages of carcinogenesis”

Authors: U. Munjal, M. Glei, B.L. Pool-Zobel, D. Scharlau