Food industries are increasingly oriented toward new foods to improve nutritional status and/or to combat nutritional deficiency diseases. In this context, silicon biofortification could be an ...innovative tool for obtaining new foods with possible positive effects on bone mineralization. In this paper, an alternative and quick in vitro approach was applied in order to evaluate the potential health-promoting effects of five silicon-biofortified leafy vegetables (tatsoi, mizuna, purslane, Swiss chard and chicory) on bone mineralization compared with a commercial silicon supplement. The silicon bioaccessibility and bioavailability of the five leafy vegetables (biofortified or not) and of the supplement were assessed by applying a protocol consisting of in vitro gastrointestinal digestion coupled with a Caco-2 cell model. Silicon bioaccessibility ranged from 0.89 to 8.18 mg/L and bioavailability ranged from 111 to 206 μg/L of Si for both vegetables and supplement. Furthermore, the bioavailable fractions were tested on a human osteoblast cell model following the expression of type 1 collagen and alkaline phosphatase. The results obtained highlighted that the bioavailable fraction of biofortified purslane and Swiss chard improved the expression of both osteoblast markers compared with the supplement and other vegetables. These results underline the potentially beneficial effect of biofortified leafy vegetables and also indicate the usefulness of in vitro approaches for selecting the best vegetable with positive bone effects for further in vivo research.
The intestinal absorption of verbascoside (VB), a phenylpropanoid glycoside, extracted and purified from olive mill waste water (OMWW), was investigated using viable and healthy human colonic ...tissues, mounted in an Ussing chamber. Additionally, VB absorption and transport through the intestinal mucosa were quantified using permeability coefficients. VB absorption was time-dependent and varied in relation to the specific colonic segments considered. In particular, major uptake/absorption (0.50μg/cm2) occurred between 5 and 15min in the proximal tract of the colon, followed by descending colon (0.38μg/cm2) between 30 and 60min, and sigmoid–rectum colon (0.34μg/cm2) at 60min. Overall, VB was absorbed rapidly, with an average uptake of 0.29μg VB per cm2, corresponding to a total accumulation efficiency of ~0.12%. Moreover, the presence of the VB in the basolateral side supported the hypothesis of its bioavailability in the extent of 0.1%. In addition, the permeability coefficient calculation has contributed in a deeper understanding of VB absorption and transport across the human intestinal barrier and could be utilized for other polyphenols present in food and in dietary supplements.
•Assessment of VB absorption and transport by human colonic tissue.•Time-dependent VB absorption related to colonic tract.•Assessment of Intestinal permeability coefficients for VB on human colon.
The gastrointestinal tract is the main target of exposure to mycotoxin fumonisin B^sub 1^ (FB^sub 1^), common natural contaminant in food. Previous studies reported that proliferating cells are more ...sensitive than confluent cells to the toxic effect of FB^sub 1^. This study aims to investigate, by dose- and time-dependent experiments on human colon proliferating intestinal cell line (HT-29), the modifications induced by FB^sub 1^ at concentrations ranging from 0.25 to 69 muM. The choice of highest FB^sub 1^ concentration considered the low toxicity previously reported on intestinal cell lines, whereas the lowest one corresponded to the lower FB^sub s^ levels permitted by European Commission Regulation. Different functional parameters were tested such as cell proliferation, oxidative status, immunomodulatory effect and changes in membrane microviscosity. In addition FB^sub 1^-FITC localization in this cell line was assessed by using confocal laser scanning microscopy. Lipid peroxidation induction was the main and early (12 h) effect induced by FB^sub 1^ at concentrations ranging from 0.5 to 69 muM, followed by inhibition of cell proliferation (up to 8.6 muM), the immunomodulatory effect (up to 17.2 muM), by assessing IL-8 secretion, and increase in membrane microviscosity (up to 34.5 muM). The toxic effects observed in different functional parameters were not dose-dependent and could be the consequence of the FB^sub 1^ intracytoplasmatic localization as confirmed by confocal microscopy results. The different timescales and concentrations active of different functional parameters could suggest different cellular targets of FB^sub 1^.PUBLICATION ABSTRACT
Cultured rat hepatocytes and human hepatoma HepG2 cells were used to evaluate the hepatoprotective properties of polyphenolic extracts from the edible part of artichoke (AE). The hepatocytes were ...exposed to H2O2generated in situ by glucose oxidase and were treated with either AE, or pure chlorogenic acid (ChA) or with the well known antioxidant, N, N'-diphenyl-p-phenilenediamine (DPPD). Addition of glucose oxidase to the culture medium caused depletion of intracellular glutathione (GSH) content, accumulation of malondialdehyde (MDA) in the cultures, as a lipid peroxidation indicator, and cell death. These results demonstrated that AE protected cells from the oxidative stress caused by glucose oxidase, comparable to DPPD. Furthermore, AE, as well as ChA, prevented the loss of total GSH and the accumulation of MDA. Treatment of HepG2 cells for 24 h with AE reduced cell viability in a dose-dependent manner, however, ChA had no prominent effects on the cell death rate. Similarly, AE rather than ChA induced apoptosis, measured by flow cytometric analysis of annexin and by activation of caspase-3, in HepG2 cells. Our findings indicate that AE had a marked antioxidative potential that protects hepatocytes from an oxidative stress. Furthermore, AE reduced cell viability and had an apoptotic activity on a human liver cancer cell line.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Artichoke is a rich source of health promoting compounds such as polyphenols, important for their pharmaceutical and nutritional properties. In this study, the potential for bioavailability of the ...artichoke polyphenols was estimated by using both in vitrodigestion and Caco-2 human intestinal cell models. In vitrodigestive recoveries (bio-accessibility) were found to be 55.8% for total artichoke phenolics and in particular, 70.0% for chlorogenic acid, 41.3% for 3,5-O-dicaffeoylquinic acid, and 50.3% for 1,5-O-dicaffeoylquinic acid, highlighting potential sensitivity of these compounds to gastric and small intestinal digestive conditions. Uptake of artichoke polyphenols was rapid with peak accumulation occurring after 30 min with an efficiency of 0.16%, according to the poor uptake of dietary polyphenols. Some compounds, such as coumaric acid, caffeic acid and caffeic acid derivatives, were also detected in the basolateral side assuming extra and intracellular esterase activities on chlorogenic acid. Only apigenin-7-O-glucoside was transported through the Caco-2 monolayer demonstrating its bioavailability to the extent of 1.15% at 60 min. In addition, permeability coefficient (P sub(app) = 2.29 10 super(-5) cm s super(-1)), involving apical to basolateral transport of apigenin 7-O-glucoside, was calculated to facilitate estimation of transport through the Caco-2 monolayer. Finally, the mono and dicaffeoylquinic acids present in artichoke heads exert an antioxidant activity on the human low density lipoprotein system correlated to their chemical structure. In conclusion, the utilized in vitromodels, although not fully responding to the morphological and physiological features of human in vivoconditions, could be a useful tool for investigating mechanistic effects of polyphenols released from the food matrix.
The gastrointestinal tract is the main target of exposure to mycotoxin fumonisin B sub(1) (FB sub(1)), common natural contaminant in food. Previous studies reported that proliferating cells are more ...sensitive than confluent cells to the toxic effect of FB sub(1). This study aims to investigate, by dose- and time-dependent experiments on human colon proliferating intestinal cell line (HT-29), the modifications induced by FB sub(1) at concentrations ranging from 0.25 to 69 mu M. The choice of highest FB sub(1) concentration considered the low toxicity previously reported on intestinal cell lines, whereas the lowest one corresponded to the lower FB sub(s) levels permitted by European Commission Regulation. Different functional parameters were tested such as cell proliferation, oxidative status, immunomodulatory effect and changes in membrane microviscosity. In addition FB sub(1)-FITC localization in this cell line was assessed by using confocal laser scanning microscopy. Lipid peroxidation induction was the main and early (12 h) effect induced by FB sub(1) at concentrations ranging from 0.5 to 69 mu M, followed by inhibition of cell proliferation (up to 8.6 mu M), the immunomodulatory effect (up to 17.2 mu M), by assessing IL-8 secretion, and increase in membrane microviscosity (up to 34.5 mu M). The toxic effects observed in different functional parameters were not dose-dependent and could be the consequence of the FB sub(1) intracytoplasmatic localization as confirmed by confocal microscopy results. The different timescales and concentrations active of different functional parameters could suggest different cellular targets of FB sub(1).
Olive mill wastewater (OMWW) is an agricultural waste material produced in high quantities in the Mediterranean basin. OMWW may be an inexpensive source of health promoting phytochemicals with ...potential economic value including many low molecular weight compounds such as verbascosides. While promising as antioxidantsin vitro, little information is available on the potential absorption of verbascosides by humans. The main objective of the present study was to characterize the verbascoside content and potential for their bioavailability from a partially purified phenolic fraction (IP) of OMWW. The IP was obtained after ultrafiltration step at 5000 Dalton and gel filtration low-pressure chromatography (LH20) of OMWW. RP-HPLC analysis identified several soluble phenolics compounds including verbascoside and isoverbascoside as major components of OMWW fractions. The potential for bioavailability of these polyphenols was estimated by using bothin vitrodigestion and Caco-2 human intestinal cell models.In vitrodigestive recoveries (bioaccessibility) were found to be 35.5%+/- 0.55% for verbascoside and 9.2%+/- 0.94% for isoverbascoside highlighting potential sensitivity of these phenolics to gastric and small intestinal digestive conditions. Accumulation of verbascosides by highly differentiated Caco-2 monolayers was linear between 10 and 100 mu M of verbascoside and isoverbascoside from IP extract. Uptake of verbascoside and isoverbascoside was rapid with peak accumulation occurring after 30 min with total accumulation efficiency of 0.1% and 0.2% providing intracellular levels of 130 and 80 pmol/mg cell protein for verbascoside and isoverbascoside, respectively. Combined, these data suggest that verbascosides present in OMWW are bioaccessible and provides a rationale for subsequentin vivostudies on the bioavailability and bioactivity of OMWW components.
A cationic soluble peroxidase isoenzyme (CysPrx) has been purified and characterized from artichoke (
Cynara cardunculus subsp.
scolymus (L.) Hegi) leaves by combination of aqueous two phase ...extraction, ion exchange chromatography, and gel filtration. The purification fold was 149 and the activity recovery 5.5%. CysPrx was stable from 5 to 45 °C with a pH optimum around 5.5; the pI was 8.3 and the MW of 37.7 ± 1.5 kDa. MALDI-TOF MS analysis provided partial peptide sequences and resolved CysPrx isoenzyme into two putative isoforms. The presence of these isoforms was confirmed by the isolation of full-length cDNA encoding CysPrx that generate two slightly different sequences coding for two putative CysPrx: CysPrx1 and CysPrx2. The obtained MS peptides showed a 35% coverage with 100% identity with the two CysPrx deduced protein sequences. A molecular modeling analysis was carried out to predict
in silico the protein structure and compare it with other plant Prx structures. Considering that CysPrx is quite stable, the study carried out in this paper will offer new insights for the production of the recombinant protein for utilization of CysPrx as an alternative Prx for food technology, biomedical analysis and bioremediation.
► Purification and biochemical characterization of a soluble cationic peroxidase from artichoke by using aqueous two phase extraction, ion exchange chromatography, gel filtration and MALDI-TOF MS analysis. ► Two isoenzymatic forms of cationic peroxidase have been identified and the full-length cDNA of these isoforms have been sequenced. ► A molecular modeling analysis has been carried out in order to predict the protein structure by using two different computational tools.
PDF
