Chemopreventive effects of in vitro digested and fermented bread in human colon cells.
OBJECTIVE
Bread as a staple food product represents an important source for dietary fibre consumption. Effects of wheat bread, wholemeal wheat bread and wholemeal rye bread on mechanisms which could have impact on chemoprevention were analysed in colon cells after in vitro fermentation.


METHODS
Effects of fermented bread samples on gene expression, glutathione S-transferase activity and glutathione content, differentiation, growth and apoptosis were investigated using the human colon adenoma cell line LT97. Additionally, apoptosis was studied in normal and tumour colon tissue by determination of caspase activities.


RESULTS
The expression of 76 genes (biotransformation, differentiation, apoptosis) was significantly upregulated (1.5-fold) in LT97 cells. The fermented bread samples were able to significantly increase glutathione S-transferase activity (1.8-fold) and glutathione content (1.4-fold) of the cells. Alkaline phosphatase activity as a marker of differentiation was also significantly enhanced (1.7-fold). The fermented bread samples significantly inhibited LT97 cell growth and increased the level of apoptotic cells (1.8-fold). Only marginal effects on apoptosis in tumour compared to normal tissue were observed.


CONCLUSIONS
This is the first study which presents chemopreventive effects of different breads after in vitro fermentation. In spite of differences in composition, the results were comparable between the bread types. Nevertheless, they indicate a potential involvement of this staple food product regarding the prevention of colon cancer.
Department of Nutritional Toxicology, Institute of Nutrition, Friedrich-Schiller-University Jena, Dornburger Strasse 24, 07743, Jena, Germany. wiebke.schloermann@uni-jena.de
Wiebke
W
Schlörmann
Beate
B
Hiller
Franziska
F
Jahns
Romy
R
Zöger
Isabell
I
Hennemeier
Anne
A
Wilhelm
Meinolf G
MG
Lindhauer
Michael
M
Glei
D000469:Alkaline Phosphatase / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D001939:Bread; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D018890:Chemoprevention / Q000379:methods*; D003106:Colon / Q000166:cytology*; D003110:Colonic Neoplasms / Q000473:pathology; D005285:Fermentation; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D046228:Microarray Analysis; D012334:RNA, Neoplasm / Q000235:genetics; D012434:Secale / Q000737:chemistry; D014908:Triticum / Q000737:chemistry; D015854:Up-Regulation
D012334:RNA, Neoplasm; D005982:Glutathione Transferase; D000469:Alkaline Phosphatase; D005978:Glutathione