Colonic availability of apple polyphenols - A study in ileostomy subjects

Abstract

Nutrition is thought to play an essential role in the pathogenesis of inflammatory and malignant gastrointestinal diseases. It is well known that plant ingredients such as polyphenols and flavonoids show anticarcinogenic effects both in vitro and in animal experiments, and may thus reduce the risk of colorectal cancer in man. The aim of the study was to determine the amount of polyphenols reaching the colon after oral intake of apple juice. After consumption of a polyphenol-free diet 11 healthy ileostomy volunteers drank 1 L of a polyphenol-rich cloudy apple juice. Ileostomy effluent was collected immediately before and 1, 2, 4, 6, and 8 h after consumption of apple juice. A broad spectrum of polyphenols was identified using HPLC-diode array detection (HPLC-DAD) as well as HPLC-ESI-MS/MS; quantitation was performed with HPLC-DAD. Most of the orally administered apple polyphenols were absorbed from or metabolized in the small intestine. Between 0 and 33% of the oral dose was recovered in the ileostomy bags with a maximum of excretion after 2 h. Phloretin glucuronide as product of polyphenol metabolism was detected in the ileostomy effluent. The present results show that most of the apple juice polyphenols are absorbed in the small intestine. Minor amounts of unmetabolized polyphenols are recovered in the ileostomy effluent, which would reach the colon under physiologic circumstances. These data have to be considered when polyphenols are used in model systems to show preventive effects in colorectal carcinogenesis.

Human intestinal hydrolysis of phenol glycosides – a study with quercetin and p‐nitrophenol glycosides using ileostomy fluid

“…In our recent ileostomy study only Q3rha and traces of Q3ara, but no Q3glc, Q3gal or Q3xyl were recovered in the ileostomy bag after ingestion and therefore would reach the colon under physiological circumstances [21]. In our present study, in which effects that happen in the oral cavity and in the stomach [26] were not considered, we observed a clearcut difference in the hydrolysis rates of quercetin glycosides depending on the sugar moiety, which is in agreement with [15] and [25].…”

“…Most of the orally administered polyphenols are absorbed or metabolized in the small intestine. In our previous studies carried out with apple polyphenols and ileostomy subjects, between 0 and 33% of the oral dose was recovered in the ileostomy bag [21]. There is evidence from the literature that quercetin glucosides are completely hydrolyzed to quercetin in the small intestine and are mostly absorbed (64.5-80.7%) [12,22] before conjugation and circulation in the plasma [23].…”

The Ussing type chamber model to study the intestinal transport and modulation of specific tight‐junction genes using a colonic cell line

“…1 and 2) in T84 model cell cultures in Ussing chambers (which are well established for in vitro studies of intestinal ion transport, drug absorption, and permeability to variously sized marker molecules and antigens in gut mucosa [25]). Polyphenol concentrations used in the incubations were comparable to physiological concentrations found in ileostomy bags of patients following consumption of cloudy apple juice [3]. Several groups have reported that some polyphenols are unstable under cell culture conditions [26 -28].…”

“…The availability of polyphenols in the gastrointestinal tract of humans has been evaluated in studies in which cloudy apple juice was consumed by ileostomists, and up to 30% of the oral dose was recovered in their ileostomy bags [3]. Metabolites of the ingested polyphenols, such as D-( -)-quinic acid, the methyl esters of caffeic acid and p-coumaric acid, 1-caffeoylquinic acid, 3-caffeoylquinic acid, phloretin 29-O-glucuronide, and the aglycone phloretin were also recovered in the effluents [4].…”

Impact of apple polyphenols on GSTT2 gene expression, subsequent protection of DNA and modulation of proliferation using LT97 human colon adenoma cells

“…Kahle et al [58] have shown that after apple juice intake only a limited amount of ingested polyphenols reach the colon unmetabolized in healthy ileostomy patients, e.g., recovery of chlorogenic acid and 3-p-coumaroylquinic acid in ileostomy bags was 10.2% and 33.1%, respectively. Therefore, regarding single compounds, 128 lg/mL AE seems to be quite high.…”