Intervention with cloudy apple juice results in altered biological activities of ileostomy samples collected from individual volunteers.
BACKGROUND
Apple juice is considered to be an important component of the healthy diet, with anticancer activities in colon cancer animal models and key ingredients have numerous chemoprotective activities in human colon cells in vitro.


OBJECTIVE
Since only little is known on comparable activities in the human colon in vivo, here a pilot study was performed to assess related mechanisms caused by ileostomy samples from volunteers that had consumed apple juice.


METHODS
Ileostomy samples were collected after intervention (0-8 h) with cloudy apple juice (1 l). They were characterized analytically for major apple polyphenols and biologically in HT29 colon cells for their potential to cause genotoxic damage, protect from the genotoxic insult by hydrogen peroxide (H(2)O(2)) and modulate the expression of GSTT2, an enzyme related to antioxidative defence against different peroxides.


RESULTS
The analytical determination of polyphenols in the ileostomy samples revealed that the majority of the compounds were recovered in the samples collected 2 h after intervention. The comparison of genotoxic effects of samples before intervention and 2 h after intervention revealed a considerable variation of genotoxic response, but there was a trend for reduced genotoxicity in three of eight persons (P) after intervention. Samples collected at 2 h protected HT29 cells from genotoxic damage by H(2)O(2) (for 4 of 8 persons), resulted in an increased GSTT2 expression (for 2 of 6 persons) and of GSTT2 promotor activity (2 of 6 persons).


CONCLUSIONS
The intervention with apple juice results in bioavailable concentrations of related polyphenols in the gut lumen, which could contribute to reduced genotoxicity, enhanced antigenotoxicity and favorable modulation of GSTT2 gene expression in some individuals. The pilot study for the first time used this combination of faecal biomarkers which in larger cohorts may either reveal overall significant alterations of chemoprotection or may be used to identify individuals which could particularly benefit from a personalized nutrition.
Veeriah
Selvaraju
S
Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA. veeriahs@mskcc.org
Balavenkatraman
Kamal Kumar
KK
Böhmer
Frank- D
F
Kahle
Kathrin
K
Glei
Michael
M
Richling
Elke
E
Scheppach
Wolfgang
W
Pool-Zobel
Beatrice L
BL
D019540:Area Under Curve; D001628:Beverages; D001682:Biological Availability; D003106:Colon / Q000378:metabolism; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000032:analysis* / Q000493:pharmacokinetics*; D005638:Fruit / Q000737:chemistry; D005982:Glutathione Transferase / Q000378:metabolism*; D019073:HT29 Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D007081:Ileostomy; D027845:Malus / Q000737:chemistry*; D009152:Mutagenicity Tests; D010636:Phenols / Q000032:analysis* / Q000493:pharmacokinetics*; D010865:Pilot Projects; D059808:Polyphenols
D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D006861:Hydrogen Peroxide; C491107:GSTT2 protein, human; D005982:Glutathione Transferase