Effects of Simulated Human Gastrointestinal Digestion of Two Purple-Fleshed Potato Cultivars on Anthocyanin Composition and Cytotoxicity in Colonic Cancer and Non-Tumorigenic Cells

Abstract

A dynamic human gastrointestinal (GI) model was used to digest cooked tubers from purple-fleshed Amachi and Leona potato cultivars to study anthocyanin biotransformation in the stomach, small intestine and colonic vessels. Colonic Caco-2 cancer cells and non-tumorigenic colonic CCD-112CoN cells were tested for cytotoxicity and cell viability after 24 h exposure to colonic fecal water (FW) digests (0%, 10%, 25%, 75% and 100% FW in culture media). After 24 h digestion, liquid chromatography-mass spectrometry identified 36 and 15 anthocyanin species throughout the GI vessels for Amachi and Leona, respectively. The total anthocyanin concentration was over thirty-fold higher in Amachi compared to Leona digests but seven-fold higher anthocyanin concentrations were noted for Leona versus Amachi in descending colon digests. Leona FW showed greater potency to induce cytotoxicity and decrease viability of Caco-2 cells than observed with FW from Amachi. Amachi FW at 100% caused cytotoxicity in non-tumorigenic cells while FW from Leona showed no effect. The present findings indicate major variations in the pattern of anthocyanin breakdown and release during digestion of purple-fleshed cultivars. The differing microbial anthocyanin metabolite profiles in colonic vessels between cultivars could play a significant role in the impact of FW toxicity on tumor and non-tumorigenic cells.

The Influence of In Vitro Gastrointestinal Digestion on the Anticancer Activity of Manuka Honey

“…Similar results were also found in the work of Ariza et al, in which the IC 50 of the HepG2 (human liver carcinoma cells) of the digested samples of strawberries and achenes were lower than the respective raw fruits [36]. Kubow et al reported that, after the digestion of two different species of purple-fleshed potatoes, their cytotoxicity on Caco-2 cells increased [37]. The higher cytotoxic effect of the digested fraction, despite the lower amount of phenolic compounds, flavonoids and antioxidant capacity, could be due to the production of metabolites with a more antiproliferative effect, but more studies will have to be carried out to understand the real effect of digestion on the production of potentially cytotoxic metabolites from the compounds initially present in the food matrix.…”

“…cancer cell line (LoVo) where a concentration of 50 mg/mL reduced colony formation by up to 80% [37], and in one breast cancer line (MDA-MB-231), where the higher concentration of MH decreased this value by up to 60% [59]. Similar results were obtained with propolis, which decreased the colonigenic capacity of two cell lines of glioblastoma (U251, U343) [60].…”

“…In the other two concentrations tested (16 and 24 mg/mL), the decrease in the number of formed colonies for both treatments was almost similar, up to a decrease of about 65% compared to the control. This activity of MH has also been confirmed in another colon cancer cell line (LoVo) where a concentration of 50 mg/mL reduced colony formation by up to 80% [37], and in one breast cancer line (MDA-MB-231), where the higher concentration of MH decreased this value by up to 60% [59]. Similar results were obtained with propolis, which decreased the colonigenic capacity of two cell lines of glioblastoma (U251, U343) [60].…”

Antioxidant Status, Antidiabetic Properties and Effects on Caco-2 Cells of Coloured and Non-Coloured Enriched Extracts of Sweet Cherry Fruits

“…in the course of oxidative stress [48]. Phenolics, essentially due to their hydroxyl and carboxyl groups exhibit promising and strong antioxidant activities being capable of capturing these radicals and chelating metals before they attack the mitochondrial membrane [42]. Particularly, 50 μM of quercetin derivatives already showed similar protective effects at preventing Caco-2 damage induced by t-BHP [50].…”

“…necrotic process in the lowest concentrations (≤ 200 μg/mL) and its occurrence in the highest concentrations (400 and 800 μg/mL), which is accompanied by an elevation of LDH in culture medium [42][43][44]. Indeed, phenolics can interfere in different steps of carcinogenesis (promotion, initiation and progression) acting as a blocking agent or as a cancer suppressor, inhibiting the metabolic action of the pre-carcinogens, and consequently, blocking the tumour initiation [44,45].…”