Plasmatic dermatan sulfate and chondroitin sulfate determination in mucopolysaccharidoses.

The evaluation of plasmatic galactosaminoglycans, dermatan sulfate (DS) and chondroitin sulfate (CS) can be helpful in the early identification of MPS patients, also considering that primary storage of one type of GAG can lead to secondary accumulation of other lysosomal substrates. We explore the possibility to determine plasmatic DS and CS in numerous healthy pediatric (and sometimes adult) subjects depending on age and in patients affected by various forms of MPS. A highly sensitive HPLC separation and fluorescence detection was applied for plasma/serum DS and CS determination after a specific enzymatic treatment able to release their constituent disaccharides. DS and CS content decrease significantly with age in controls having high values in the first year (~8 µg/mL). A highly significant decrease was observed for 1-5-year-old (∼-33%) and 5-10-year-old (∼-65%) healthy subgroups. No further decrease was determined showing a stabilization after 5 years of age. MPS I Scheie and Hurler patients showed rather similar DS and CS content significantly higher than controls matched for age. Similarly, MPS II, III and IV subjects all presented significantly higher plasmatic DS and CS content compared to healthy subjects matched for age. The same trend was determined for the only patient affected by MPS VI. Plasmatic DS and CS analyzed by the present procedure may be a useful diagnostic and screening marker for various forms of MPS.

Oligosaccharides in 4 different milk groups, Bifidobacteria, and Ruminococcus obeum.

OBJECTIVES: The aim of this study was to identify a link between the total amount of breast milk oligosaccharides and faecal microbiota composition of newborns at the end of the first month of life, with special attention paid to bifidobacteria, and establish the role, if any, of the different oligosaccharides in determining the gut microbiota composition. SUBJECTS AND METHODS: Milk oligosaccharide groups were identified by high-performance anion exchange chromatography analysis. DPCRNA from newborns' faecal samples at 30 days of life was isolated and processed by polymerase chain reaction analyses that allow the identification of 6 species of bifidobacteria (adolescentis, bifidum, breve, catenulatum, longum, infantis) and Ruminococcus spp; denaturing gradient gel electrophoresis analysis was also performed. RESULTS: No substantial differences in bifidobacteria species composition within milk groups 1, 2, and 3 were observed; however, infants fed with group 4 milk show a microbiota characterised by a greater frequency of Bifidobacteria adolescentis and the absence of Bifidobacteria catenulatum. For the first time, a high percentage of the Ruminococcus genus in infants fed with all milk groups was found. CONCLUSIONS: Our data show that milk groups 1, 2, and 3, containing an amount of oligosaccharides ranging within 10 to 15 g/L, share a substantially identical composition of the intestinal microbiota in breast-fed infants, despite quali-quantitative difference in oligosaccharides content. Newborns taking milk with only 5 g/L of oligosaccharides (group 4) harbour a different intestinal microbiota.

Human milk oligosaccharides inhibit the adhesion to Caco-2 cells of diarrheal pathogens: Escherichia coli, Vibrio cholerae, and Salmonella fyris.

Breast-fed children, compared with the bottle-fed ones, have a lower incidence of acute gastroenteritis due to the presence of several antiinfective factors in human milk. The aim of this work is to study the ability of human milk oligosaccharides to prevent infections related to some common pathogenic bacteria. Oligosaccharides of human milk were fractionated by gel-filtration and characterized by thin-layer chromatography and high-performance anion exchange chromatography. Fractions obtained contained, respectively, 1) acidic oligosaccharides, 2) neutral high-molecular-weight oligosaccharides, and 3) neutral low-molecular-weight oligosaccharides. Experiments were carried out to study the ability of oligosaccharides in inhibiting the adhesion of three intestinal microorganisms (enteropathogenic Escherichia coli serotype O119, Vibrio cholerae, and Salmonella fyris) to differentiated Caco-2 cells. The study showed that the acidic fraction had an antiadhesive effect on the all three pathogenic strains studied (with different degrees of inhibition). The neutral high-molecular-weight fraction significantly inhibited the adhesion of E. coli O119 and V. cholerae, but not that of S. fyris; the neutral low-molecular-weight fraction was effective toward E. coli O119 and S. fyris but not V. cholerae. Our results demonstrate that human milk oligosaccharides inhibit the adhesion to epithelial cells not only of common pathogens like E. coli but also for the first time of other aggressive bacteria as V. cholerae and S. fyris. Consequently, oligosaccharides are one of the important defensive factors contained in human milk against acute diarrheal infections of breast-fed infants.