Sabine Kuntz

Justus-Liebig-Universität Gießen | JLU · Institute of Nutritional Sciences

Inflammasomes are multi-protein complexes, which are formed in response to tissue injury, infections, and metabolic stress. However, aberrant inflammasome activation has been linked to several inflammatory diseases. Anthocyanins have been reported to attenuate NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation, but the influence o...

Scope 2´-Fucosyllactose (2´-FL), the most abundant oligosaccharide in human milk, plays an important role in numerous biological functions, including improved learning. It is not clear, however, whether 2´-FL or a cleavage product could influence neuronal cell activity. Thus, we investigated the effects of 2´-FL, its monosaccharide fucose (Fuc), an...

Pancreatic cancer is primarily considered to be a metastatic disease with a low 5-year survival rate. We aimed to detect if plasma-isolated anthocyanins and their metabolites (PAMs) modulate pancreatic cancer cells migration and to describe molecular targets of PAMs in this process. Plasma metabolites were isolated by solid-phase extraction before...

Cancer mortality is mainly due to metastasis. Therefore, searching for new therapeutic agents suppressing cancer cell migration is crucial. Data from human studies regarding effects of anthocyanins on cancer progression, however, are scarce and it is unclear whether physiological concentrations of anthocyanins and their metabolites reduce cancer ce...

Objectives/Background: Anthocyanins (ACN) are polyphenols present in fruits like blueberries and grapes. The majority of the ingested ACN can reach the large intestine where they are extensively metabolized by gut microbiota. The study aimed to identify biomarkers of ACN intake by a nutrimetabolomics approach in plasma, urine and feces using an UHP...

Scope To further examine the role of the human milk oligosaccharide 2’fucosyllactose (2´FL) and fucose (Fuc) in cognition. Using ¹³C-labelled 2’FL, we previously showed in mice that ¹³C-enrichment of the brain was not caused by ¹³C1-2´FL itself, but rather by microbial metabolites. Here, we applied ¹³C1-Fuc in the same mouse model to investigate it...

Milk sialyllactose (SL) and sialic acids (SA) are considered to be crucial for brain composition and development. To investigate their metabolic fate, we administered ¹³C-labelled 3′SL (¹³C-3′SL) and ¹³C-N-acetylneuraminic acid (¹³C-Neu5Ac) to NMRI mice. From per oral and intravenous (i.v.) applications, an organ specific ¹³C-enrichment can be excl...

Scope 2´‐fucosyllactose (2´FL) is an abundant oligosaccharide in human milk. It is hypothesized that its brain enrichment is associated with improved learning. Accumulation of 2´FL in organs, biological fluids and feces was assessed in wild‐type and germ‐free mice. Methods and results ¹³C‐labelled 2´FL was applied to NMRI wild‐type mice intravenou...

Oligosaccharides are present in human milk (HMO) in large amounts and in a high variety: Among other functions they are considered to influence the gut microbiota and gut maturation in infants. Due to the large volume of milk available bovine milk oligosaccharides (BMO) may be an alternative source of functional ingredients to potentially mimic HMO...

Human milk oligosaccharides (HMO) are major components of breast milk that may have local effects in the gastrointestinal tract and systemic functions after being absorbed, both depending on their metabolism. Using preterm pigs, we investigated the metabolic fate of HMO in three experiments with two different HMO blends. In addition, we examined ef...

Probiotics are considered to have a beneficial impact on humans, but in some cases, administration of live microorganisms might be risky. In the present study, immunomodulatory effects of different Escherichia coli strains and their supernatants were examined under different inflammatory conditions with living and heat-inactivated strains. HT-29 ce...

Purpose: Pancreatic cancer is an aggressive cancer type, of which the most important characteristics are migration and metastasis. Anthocyanins (ACN) are discussed to be protective phytochemicals; however, up to now only scarce data are available regarding their effects on cancer prevention. In this study, we aimed to determine whether ACN and the...

The anti-inflammatory effects of anthocyanins (ACNs) on vascular functions are discussed controversially because of their low bioavailability. This study was performed to determine whether microorganism (MO)-fermented ACNs influence vascular inflammation in vitro. Therefore, MO growth media were supplemented with an ACN-rich grape/berry extract and...

The goal of eating five servings of fruits and vegetables a day has not yet been achieved. The intake of polyphenols such as anthocyanins (ACN) could be improved by consuming smoothies and juices that are increasingly popular, especially in children; however, bioavailability data concerning food matrix effects are scarce. Thus, we conducted a rando...

Background: Anthocyanins (ACNs) are the most prevalent flavonoids in berries and their health promoting effects on vascular functions are still discussed. The aim of the present study was to identify the anti-inflammatory effect of ACNs on activated human umbilical vein endothelial cells (HUVECs) after their transport across an epithelial monolaye...

Anthocyanins (ACN) can exert beneficial health effects not only through their antioxidative potential but also through modulation of inflammatory parameters that play a major role in CVD. A randomised cross-over study was carried out to investigate the effects of ACN-rich beverage ingestion on oxidation- and inflammation-related parameters in thirt...

The beneficial effects of vegetables such as leafy cabbage (Brassica oleracea) on health are attributed to their anti-oxidative and anti-inflammatory potential. Therefore, we investigated whether curly kale extracts affect cytokine induced expression of endothelial cell adhesion molecules as well as the adhesion of leukocytes to endothelial cells d...

Since the discovery of human milk oligosaccharides (HMO) more than 60 years ago, research has faced major challenges including (i) the development of methods to identify and characterize these components, (ii) the need to use HMO fractions for functional studies since single HMO were not available, (iii) the uncertainty of the purity of HMO fractio...

Pancreatic tumor cell migration has important roles in cancer progression and is associated with poor prognosis. We investigated whether circulating plasma anthocyanins and their metabolites (PAM) deriving from fruit juice intake affect cell migration through modulation of the expression of matrix metalloproteinases MMP‐2 and MMP‐9. Ten healthy sub...

The global trend of the phenomenon of population ageing has dramatic consequences on public health and the incidence of neurodegenerative diseases. Physiological changes that occur during normal ageing of the brain may exacerbate and initiate pathological processes that may lead to neurodegenerative disorders, especially Alzheimer's disease (AD). H...

The carbonyl compounds methylglyoxal (MG) and glyoxal (GL) are reactive intermediates of glucose degradation pathways and capable of inducing cellular damage. Although immune-stimulating activity has been investigated in endothelial cells, little is known about the signaling pathways of cytokine induction of these compounds in the intestine. Hence,...

ATP-driven efflux pumps such as phosphoglycoprotein-170 (P-gp), multidrug-resistance-associated protein-2 (MRP-2), or breast cancer resistance protein (BCRP) play a crucial role in limiting the efficacy of tumor pharmacotherapy. Selected flavonoids have been suggested to inhibit individual efflux-transporters and to act therefore as multidrug-resis...

The carbonyl compounds methylglyoxal (MG) and glyoxal (G) are reactive intermediates generated in a variety of foods and beverages during processing and prolonged storage. We investigated direct effects of these compounds on intestinal cells determining the basal and stimulated secretion of IL-8 and IL-6 in vitro. MG or G induced a concentration de...

Oligosaccharides are present in human milk in large amounts and in a high variety. We have previously shown that these oligosaccharides are strong inhibitors of proliferation and inducers of differentiation in intestinal cell lines. To elucidate the molecular mechanism, we investigated the influence on cell cycle events via flow cytometry and expre...

Background Intestinal epithelial cells play an important role in mucosal immune reactions via production and expression of chemokines such as interleukin‐8 (IL‐8) being involved in carbohydrate mediated neutrophil adhesion and infiltration. Sialylated milk oligosaccharides have previously been shown to inhibit these inflammatory processes. Methods...

Background The nutritional impact of vegetables such as kale (Brassica oleraceae) has long been expected to reveal anti‐inflammatory potential. Therefore, we investigated whether water (ws) and fat soluble (fs) extracts of green cabbage affects cytokine induced expression of endothelial cell adhesion molecules as well as the adhesion of leukocytes...

The intestinal colonisation with a balanced microflora is of major importance for an appropriate development of the immune system. In recent years, there has been increasing scientific and commercial interest in modifying the flora for health promotion. Dietary factors that are thought to be effective in that context are the so-called prebiotics, i...

Human milk oligosaccharides (HMO) are considered to influence the composition of the gut microflora in breastfed infants. We investigated direct effects of milk HMO fractions or individual oligosaccharides on proliferation, differentiation and apoptosis in transformed human intestinal cells (HT-29 and Caco-2) and non-transformed small intestinal ep...

Induction of Unscheduled DNA Synthesis by the Mycotoxin Ochratoxin A in Cultured Urothelial Cells from Pigs and Humans In vitro Covalent Binding as a Possible Quantitative Indicator for the Genotoxic Potency of Aflatoxin B1 in Rat and Human N-Palmitoyl-HFB1: A New Metabolite of Hydrolyzed Fumonisin (HFB1) in Rat Liver Microsomes Are Nitroso Bile Ac...

Pulmonary surfactant given to infants and adults with respiratory failure is metabolized and recycled to a large extent. A small proportion also enters the circulation in cases of increased permeability of the alveolar-capillary membrane. We therefore investigated whether exogenous surfactants such as a natural bovine (natSF) or a synthetic (synSF)...

A high dietary intake of plant foods is thought to contribute to the prevention of colorectal cancers in humans and flavonoids as part of such a diet are considered to contribute to those protective effects. Quercetin is a major dietary flavonoid consumed with a diet rich in onions, tea, and apples. We used HT-29 human colon cancer cells and invest...

Development of resistance of cells toward proapoptotic signals is regarded as one of the key processes that allow tumor development. To identify proteins that are crucial for the initiation of apoptosis in NCOL-1 human preneoplastic colonocytes, we analyzed the proteome of cells exposed to the flavonoids flavone and quercetin that differ in their a...

The efficacy of antineoplastic compounds can depend heavily on the genetic background of the cells exposed to the drugs. This becomes evident by the fact that HT-29 human colon cancer cells but not primary murine nontransformed colonocytes are efficiently submitted to apoptosis by the flavonoid flavone. By determining caspase-3 activation, plasma m...

In cells lacking a functional p53 tumor suppressor protein, the endogenous free radical nitric oxide (NO) appears to inhibit apoptosis, and thereby promotes growth of cancer cells. In order to elucidate the underlying mechanisms on a molecular basis, we used HT-29 human colon carcinoma cells, carrying a p53 loss-of-function mutation, and examined t...

Ca2+ channel blockers like nifedipine have been shown to increase the oral bioavailability of β-lactam antibiotics, such as cefixime, in humans. The molecular mode of action of Ca2+ channel blockers on β-lactam absorption, however, has not yet been defined. Using the Caco-2 human intestinal epithelial cell line, we assessed whether alterations in i...

We have tested 33 flavonoids, occurring ubiquitously in foods of plant origin, for their ability to alter the transport of the beta-lactam antibiotic cefixime via the H+-coupled intestinal peptide transporter PEPT1 in the human intestinal epithelial cell line Caco-2. Of the flavonoids tested, quercetin, genistein, naringin, diosmin, acacetin, and c...

Flavonoids are polyphenolic compounds that occur ubiquitously in plants. They are discussed to represent cancer preventive food components in a human diet that is rich in fruits and vegetables. To understand the molecular basis of the putative anticancer activity of flavonoids, we investigated whether and how the core structure of the flavones, 2-p...

Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Their proposed protective role in tumor development may prevail especially in the intestinal tract due to direct exposure of intestinal epithelia to these dietary ingredients. We have screened more than 30 flavonoids for their effects on cell proliferation and p...

Di- and tripeptides and peptide mimetics such as beta-lactam antibiotics are efficiently reabsorbed from the tubular lumen by a high-affinity peptide transporter. We have recently identified and characterized this H+-coupled high-affinity peptide transport system in the porcine proximal tubular cell line LLC-PK1. Here we describe for the first time...

Reabsorption of filtered di- and tripeptides and peptide mimetics from the tubular lumen into renal epithelial cells is mediated by a H+-coupled high affinity transport process. Here we describe the characteristics of uptake of the radiolabeled dipeptide 3H-D-Phe-L-Ala into porcine proximal tubule LLC-PK1 cells. Saturable dipeptide influx occurs wi...