Differences in Plasma 25-Hydroxyvitamin D Levels at Diagnosis of Celiac Disease and Type 1 Diabetes.

AIM: The aim of this work is to assess the vitamin D levels, evaluated as plasma 25-hydroxyvitamin D of children with a new diagnosis of celiac disease (CD), of children with a new onset of type 1 diabetes (T1D) and in children with CD at diagnosis of T1D (T1D&CD). METHODS: In this single-center observational study, we collected data for four groups of children and adolescents: T1D, CD, T1D&CD, and a control group (CG). The CG included schoolchildren who had negative results during a mass screening campaign for CD and were not diagnosed for T1D, according to RIDI Marche registry data, were considered for the purposes of this study. Plasma 25-hydroxyvitamin D, 25(OH)D2, and 25(OH)D3 were considered as the parameters for evaluating vitamin D nutritional status, and the date of measurement was recorded to analyze vitamin D level seasonality. Vitamin D nutritional status was categorized as follows: severe deficiency (<10 ng/mL), deficiency (<20 ng/mL), insufficiency (20-29 ng/mL), or sufficiency/adequacy (≥30 ng/mL). The Kruskal-Wallis test was used to compare the groups. The association of 25(OH)D levels with health conditions and seasonal differences of 25(OH)D levels was analyzed using a multiple linear regression model. RESULTS: The number of children enrolled for the present study was 393: 131 in the CG, 131 CD, 109 T1D, and 22 T1D&CD. Significantly lower levels of vitamin D were displayed for children with CD, T1D, or both the diseases. Interestingly, severe vitamin D deficiency was detected in no children with CD, 1.5% of children in the CG, in 24.4% with T1D, and 31.8% with T1D&CD (p < 0.001). As expected, the CG children vitamin D levels were significantly influenced by seasonality. Contrarily, no seasonal differences were reported in children with CD, T1D, and T1D&CD. Multiple regression analysis showed that children with T1D and T1D&CD had lower 25(OH)D levels of 9.9 ng/mL (95% CI: 5.4; 14.5) and 14.4 ng/mL (95% CI: 6.2-22.7) compared to CG children (p < 0.001). CONCLUSIONS: Our results showed low levels of vitamin D diagnosis of T1D, CD, and T1D&CD; however, severe deficiency was only reported in children with T1D and T1D&CD. More studies are needed to better understand the role of this deficiency in children newly diagnosed with CD and T1D.

First experience of combined enzyme replacement therapy and hematopoietic stem cell transplantation in alpha-mannosidosis.

We describe the first case of bridge therapy in alpha-mannosidosis (AM) in an infant diagnosed at only 5 months of life who underwent enzyme replacement therapy (ERT) in the pre- and peri-transplant phases. Eight ERT infusions were administered before hematopoietic stem cell transplantation (HSCT) and continued for additional 90 days until complete engraftment. The clinical and laboratory data after 3 years post-HSCT show that the early combined intervention may reduce the disease progression and the urine and plasma content of mannosyl-oligosaccharides (OS) monitored by liquid chromatography tandem mass spectrometry (LC-MS/MS). This report highlights that early diagnosis and prompt initiation of such treatments in AM are the best chance to minimize the progression of symptoms.

Vitamin D status in healthy Italian school-age children: a single-center cross-sectional study.

BACKGROUND: Vitamin D is involved in calcium homeostasis and bone metabolism, although its extra-skeletal actions are also well-known. Low serum 25(OH)D levels are common both in adults and children worldwide. METHODS: The purpose of this cross-sectional study was to determine the distribution of 25(OH)D levels in a cohort of healthy Italian school-age children, aged 5-10 years, in relationship to determinants of vitamin D deficiency such as season, BMI, gender, age and ethnicity. RESULTS: The mean serum 25(OH) D level was 28.2 ng/mL; the prevalence of 25(OH)D sufficiency (> 30 ng/mL), insufficiency (20-30 ng/mL), deficiency (10-20 ng/mL) and severe deficiency (< 10 ng/mL) was 36%, 37%, 21% and 6% of the study-group population, respectively. The lower serum 25(OH)D values were observed during winter (21.6 ng/mL) and spring (22.9 ng/mL), as compared to summer (46.7 ng/mL) (p < 0.001). Higher BMI z-scores were associated with lower 25(OH)D level while no statistical difference was observed as related to gender and age groups. CONCLUSIONS: Healthy Italian schoolchildren show low 25(OH)D levels, particularly during winter and spring time. Seasonality, ethnicity and overweight/obesity were confirmed to influence the vitamin D status, thus indicating the need for effective initiatives to support adequate vitamin D status in this population group.

The Role of Nutrition in Immune-Mediated, Inflammatory Skin Disease: A Narrative Review.

Immune-mediated inflammatory skin diseases are characterized by a complex multifactorial etiology, in which genetic and environmental factors interact both in genesis and development of the disease. Nutrition is a complex and fascinating scenario, whose pivotal role in induction, exacerbation, or amelioration of several human diseases has already been well documented. However, owing to the complexity of immune-mediated skin disease clinical course and breadth and variability of human nutrition, their correlation still remains an open debate in literature. It is therefore important for dermatologists to be aware about the scientific basis linking nutrition to inflammatory skin diseases such as psoriasis, atopic dermatitis, hidradenitis suppurativa, bullous diseases, vitiligo, and alopecia areata, and whether changes in diet can influence the clinical course of these diseases. The purpose of this narrative review is to address the role of nutrition in immune-mediated inflammatory skin diseases, in light of the most recent and validate knowledge on this topic. Moreover, whether specific dietary modifications could provide meaningful implementation in planning a therapeutic strategy for patients is evaluated, in accordance with regenerative medicine precepts, a healing-oriented medicine that considers the whole person, including all aspects of the lifestyle.

Quantification of Accidental Gluten Contamination in the Diet of Children with Treated Celiac Disease.

A strict gluten-free diet is extremely difficult to maintain. Protracted ingestion of gluten traces (>10 mg/day) is sufficient to cause significant damage in the architecture of the small intestinal mucosa in patients on treatment for celiac disease. The aim of this study was to directly measure the level of contaminating gluten in the daily diet of celiac children following a gluten-free diet. From April 2019 to December 2019, celiac disease children (2-18 years old) on a gluten-free diet for ≥6 months were offered to participate in this prospective-observational study. Patients and their caregivers were invited to provide a representative portion (about 10 g) of all meals consumed during a 24-h period. Participants were requested to weigh all ingested food and report items in a 24-h food diary. The gluten content was quantified by the R5 sandwich enzyme-linked immunosorbent assay method. Sixty-nine children completed the protocol. Overall, 12/448 (2.7%) food samples contained detectable amounts of gluten; of them, 11 contained 5-20 ppm and 1 >20 ppm. The 12 contaminated food samples belonged to 5/69 enrolled patients. In these 5 children, the daily gluten intake was well below the safety threshold of 10 mg/day. The present findings suggest that in a country characterized by high celiac disease awareness, the daily unintended exposure to gluten of treated celiac children on regular follow-up is very low; reassuringly, the presence of gluten traces did not lead to exceed the tolerable threshold of 10 mg/day of gluten intake in the gluten-free diet.

Lower Level of Plasma 25-Hydroxyvitamin D in Children at Diagnosis of Celiac Disease Compared with Healthy Subjects: A Case-Control Study.

OBJECTIVE: To evaluate the vitamin D status of children with a new diagnosis of celiac disease compared with healthy controls. STUDY DESIGN: This was a case-control study. Cases were consecutive children with newly diagnosed celiac disease. Controls were healthy children matched for age, sex, ethnicity, and month of blood testing. Plasma 25-hydroxyvitamin D (25-OHD) was measured as the index of vitamin D nutritional status. The Student t test was used for comparisons. Differences in frequencies were evaluated with the χ2 test. Associations between variables were estimated by calculating Pearson correlation coefficients. RESULTS: There were 131 children with celiac disease enrolled (62% females; mean age 8.1 ± 1.1 years). The control group included 131 healthy children (62% females; mean age 8.2 ± 1.2). All were of European origin. Plasma 25-OHD levels were significantly lower in patients than in controls (25.3 ± 8.0 and 31.6 ± 13.7 ng/mL; P < .0001). The percentage of children with vitamin D deficiency (<20 ng/mL) was significantly higher in children with celiac diseaseas compared with controls (31% vs 12%; P < .0001). The concentration of 25-OHD was significantly lower in patients than in controls during summer (P < .01) and autumn (P < .0001). CONCLUSIONS: In this case-control study, at diagnosis, children with celiac disease showed lower levels of plasma 25-OHD compared with healthy subjects. Vitamin D status should be checked at diagnosis of celiac disease, particularly during summer and fall months.

Early biochemical effects of velmanase alfa in a 7-month-old infant with alpha-mannosidosis.

Alpha mannosidosis is an ultrarare pathology with variable phenotypic manifestations, characterized by the deficiency of lysosomal alpha mannosidase which causes accumulation of neutral oligosaccharides. Until recently, the hematopoietic stem cell transplantation was the only clinical feasible therapeutic option. Only in 2018, the European Medicines Agency's committee approved the recombinant enzyme velmanase alfa for long-term treatment of non-neurological manifestations in mild and moderate forms of alpha-mannosidosis. In this study, the very early biochemical effects of enzyme replacement therapy in in a 7-month-old patient with alpha-mannosidosis were described. Velmanase alpha was administered as supporting therapy awaiting for hematopoietic stem cell transplantation, the treatment chosen for the patient because of the early onset form. The results showed that the enzyme replacement therapy was able to reduce the content of three different mannosyl-oligosaccharides monitored by tandem mass spectrometry after 2 months of treatment. In particular, the mean relative changes from baseline values were -67% in urine and -53% in serum at the latest observation. The study also showed that the enzymatic activity detected in serum 1 week after the first infusion was four times higher than the normal values and constant in the following points of observation. These findings led us to assume that velmanase alfa might be biologically active in this young patient.

Increased Prevalence of Celiac Disease in School-age Children in Italy.

BACKGROUND & AIMS: Celiac disease is one of the most common diseases worldwide, with an apparent trend of increasing prevalence. We investigated the prevalence of celiac disease in children in Italy in 2015-2016 and compared that with data from 25 years ago. METHODS: We screened 4570 children (5-11 years old, 80.1% of the eligible population) from metropolitan areas of Ancona and Verona for HLA genes associated with increased risk of celiac disease, and for total serum levels of IgA and IgA class anti-tissue transglutaminase in HLA positives. Diagnoses of celiac disease were confirmed by detection of anti-endomysial antibody and analysis of intestinal biopsies. The prevalence of celiac autoimmunity and celiac disease were calculated and compared with values from the same geographical area during the years 1993-1995, after adjustment for the different diagnostic algorithm. RESULTS: We identified 1960 children with celiac disease-associated haplotypes (43% of children screened; 95% CI, 40.8%-45.2%). The prevalence of celiac disease autoimmunity in the HLA-positive subjects was 96/1706 (5.62%; 95% CI, 4.53%-6.71%) and 54 of these children satisfied the diagnostic criteria for celiac disease. In the eligible population there were other 23 known cases of celiac disease. The overall estimated prevalence of celiac disease was 1.58% (95% CI, 1.26%-1.90%); this value is significantly higher than the 1993-1995 adjusted prevalence (0.88%; 95% CI, 0.74%-1.02%). CONCLUSIONS: We found the prevalence of celiac disease in children in Italy to be greater than 1.5%; this value has increased significantly over the past 25 years. Studies are needed to determine the causes of this large increase.

False positive screen test for mucopolysaccharidoses in healthy female newborns.

BACKGROUND: In total, 930 urine samples obtained on 2nd and 3rd day from birth have been analyzed for the early diagnosis of Mucopolysaccharidoses. METHODS: Dimethylmethylene blue (DMB) assay and one-dimensional electrophoresis were performed in all urine samples. Agarose gel electrophoresis, before and after treatment with chondroitinase ABC and heparinases, was used for a comprehensive characterization. RESULTS: Out of 930 urine samples 7 showed anomalous electrophoretic pattern; 5 of them had high GAG levels by DMB test. Atypical samples (n = 7) were analyzed by agarose gel electrophoresis. After enzymatic digestion, some slow bands were still visible. A second urine sample of the above 7 newborns was analyzed at the age of 1 month, demonstrating both a normal pattern and normal GAG levels. Additional urine and vaginal mucus samples from 10 term neonates with vaginal bleeding showed the same electrophoretic pattern observed in the 7 false positive samples. CONCLUSIONS: The altered electrophoretic pattern may be due to the presence of glycoproteins and not to specific GAGs, due to high levels of maternal hormones exposure during pregnancy. To our knowledge, this is the first time maternal estrogen hormones are proposed as a likely cause of false-positive urinary glycosaminoglycan screen test in healthy newborns.

Composition and structure of glycosaminoglycans in DBS from 2-3-day-old newborns for the diagnosis of mucopolysaccharidosis.

Dried blood spot (DBS) technology is a cheap and easy method largely applied in newborn screening. Mucopolysaccharidoses (MPS) are characterized by the deficit of enzymes that degrade glycosaminoglycans (GAGs) characterized by progressive worsening of the conditions. For a possible early diagnosis of MPS, we developed a method of uronic acid (UA)-GAGs determination in DBS of 600 healthy newborns and from a small group of MPS subjects matched for age. Spotted blood UA-GAGs of the normal newborns are composed of 67.2% chondroitin sulfate (CS), 28.6% heparan sulfate (HS) and 4.4% hyaluronic acid with a CS/HS ratio of 2.35 and a total GAGs content of 0.43 µg/DBS. A chemical evaluation of CS and HS structure was performed by measuring their disaccharide composition, sulfation and the overall charge density. The DBS of four different MPS types presented an increase of total or single UA-GAGs content and/or modifications of the CS and HS disaccharide composition as well as chemical signature also related to the MPS enzymatic defect. The modifications of the UA-GAGs composition, parameters and structure of healthy newborns determined in DBS would be useful for a possible early diagnosis of various MPS types.

Safety of Oats in Children with Celiac Disease: A Double-Blind, Randomized, Placebo-Controlled Trial.

OBJECTIVE: To evaluate the long-term validity and safety of pure oats in the treatment of children with celiac disease. STUDY DESIGN: This noninferiority clinical trial used a double-blind, placebo-controlled, crossover design extended over 15 months. Three hundred six children with a biopsy-proven diagnosis of celiac disease on a gluten-free diet for ≥2 years were randomly assigned to eat specifically prepared gluten-free food containing an age-dependent amount (15-40 g) of either placebo or purified nonreactive varieties of oats for 2 consecutive 6-month periods separated by washout standard gluten-free diet for 3 months. Clinical (body mass index, Gastrointestinal Symptoms Rating Scale score), serologic (IgA antitransglutaminase antibodies, and IgA anti-avenin antibodies), and intestinal permeability data were measured at baseline, and after 6, 9, and 15 months. Direct treatment effect was evaluated by a nonparametric approach using medians (95% CI) as summary statistic. RESULTS: After the exclusion of 129 patients who dropped out, the cohort included 177 children (79 in the oats-placebo and 98 in the placebo-oats group; median, 0.004; 95% CI, -0.0002 to 0.0089). Direct treatment effect was not statistically significant for clinical, serologic, and intestinal permeability variables (body mass index: median, -0.5; 95% CI, -0.12 to 0.00; Gastrointestinal Symptoms Rating Scale score: median, 0; 95% CI, -2.5 to 0.00; IgA antitransglutaminase antibodies: median, -0.02; 95% CI, -0.25 to 0.23; IgA anti-avenin antibodies: median, -0.0002; 95% CI, -0.0007 to 0.0003; intestinal permeability test: median, 0.004; 95% CI, -0.0002 to 0.0089). CONCLUSIONS: Pure nonreactive oat products are a safe dietary choice in the treatment of children with celiac disease. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00808301.

Validation of a novel single-drop rapid human leukocyte antigen-DQ2/-DQ8 typing method to identify subjects susceptible to celiac disease.

BACKGROUND AND AIM: Human leukocyte antigen (HLA)-DQ2 and/or -DQ8 is an essential risk factor for celiac disease (CD). About 90-95% of patients with CD carry HLA-DQ2/-DQ8 alleles, and HLA-DQ typing is considered an additional diagnostic test. Conventional polymerase chain reaction (PCR)-based HLA-DQ typing methods are expensive, complex, and a time-consuming process. We assessed the efficacy of a novel HLA-DQ typing method, "Celiac Gene Screen," for the detection of CD-associated HLA haplotypes. METHODS: To assess the diagnostic performance of the Celiac Gene Screen test, 100 ethylenediaminetetraacetic acid (EDTA) blood samples, already characterized by the conventional HLA-DQ typing method, that is, PCR sequence-specific oligonucleotide probes (PCR-SSOP), a concordance between both the methods were explored. For validity, a further 300 EDTA blood samples with unknown HLA-DQ status were genotyped using the Celiac Gene Screen test, including 141 samples from CD, 56 first-degree relatives (FDRs) of CD and 103 samples from controls. RESULTS: Of the 100 samples with known status of HLA-DQ alleles, 79 samples were HLA-DQ2 and/or -DQ8 positive, and 21 samples were HLA-DQ2 and/or -DQ8 negative by conventional PCR. These 100 samples were re-typed using the Celiac Gene screen kit; all 79 positives were typed positive, and 21 negatives were typed negative for HLA-DQ alleles. Among 300 samples with unknown HLA-DQ status, 118 of 141 (84%) patients with CD, 48 of 56 (86%) FDRs of CD, and 52 of 103 (50%) controls typed positive for HLA-DQ alleles. CONCLUSIONS: The Celiac Gene Screen HLA-DQ typing method showed excellent concordance with the conventional HLA-DQ typing method and could be a cost-reducing and effective method for CD-associated HLA screening.

Age-related modulation of plasmatic beta-Galactosidase activity in healthy subjects and in patients affected by T2DM.

ß-Galactosidase (ß-Gal) activity has been the most extensively utilized biomarker for the detection of cellular senescence. It can be measured also in plasma, and few recent evidence showed an altered plasmatic ß-Gal activity in patients affected by some age-related diseases (ARDs). Since T2DM is one of the most common ARDs, we aimed to investigate if plasmatic ß-Gal activity is modulated in T2DM patients and if "age" could affect such modulation. To gain mechanistic insights we paralleled this investigation with the evaluation of ß-Gal activity in young and senescent endothelial cells (HUVECs) cultured in normo- and hyper-glycaemic environment. A significant age-related increase of plasmatic ß-Gal activity was observed in healthy subjects (n. 230; 55-87 years), whereas the enzymatic activity was significantly reduced in T2DM patients (n. 230; 55-96 years) compared to healthy subjects. ß-Gal activity detectable both in cells and in the culture medium was significantly increased in senescent cells compared to the younger ones, both under normo- and hyper-glycaemic condition. However, the hyper-glycaemic condition was not associated with an increased ß-Gal activity in milieu compared to normo-glycaemic condition. Overall our data reinforce the notion that plasmatic ß-Gal activity could be a systemic biomarker of aging, whereas T2DM patients are characterized by a different age-releated trend.

Effects of the Exclusive Enteral Nutrition on the Microbiota Profile of Patients with Crohn's Disease: A Systematic Review.

The mechanisms behind the efficacy of exclusive enteral nutrition (EEN) in Crohn's disease (CD) remain poorly understood, despite the high rate of treatment response. Evidence accumulated in the last 20 years suggests that a positive shift of the disrupted microbiota is one of the treatment effects. The purpose of this study was to critically review and summarize data reporting the microbiological effects of EEN in patients with CD. Fourteen studies were considered in the review, overall involving 216 CD patients on EEN. The studies were heterogeneous in methods of microbiota analysis and exclusion criteria. The most frequently reported effect of EEN was a reduction in microbiota diversity, reversible when patients returned to a normal diet. The effect of EEN on specific bacteria was very variable in the different studies, partially due to methodological limitations of the mentioned studies. The EEN seem to induce some metabolomic changes, which are different in long-term responder patients compared to patients that relapse earlier. Bacterial changes can be relevant to explaining the efficacy of EEN; however, microbiological data obtained from rigorously performed studies and derived from last generation techniques are largely inconsistent.

Gluten Contamination in Naturally or Labeled Gluten-Free Products Marketed in Italy.

BACKGROUND: A strict and lifelong gluten-free diet is the only treatment of celiac disease. Gluten contamination has been frequently reported in nominally gluten-free products. The aim of this study was to test the level of gluten contamination in gluten-free products currently available in the Italian market. METHOD: A total of 200 commercially available gluten-free products (including both naturally and certified gluten-free products) were randomly collected from different Italian supermarkets. The gluten content was determined by the R5 ELISA Kit approved by EU regulations. RESULTS: Gluten level was lower than 10 part per million (ppm) in 173 products (86.5%), between 10 and 20 ppm in 9 (4.5%), and higher than 20 ppm in 18 (9%), respectively. In contaminated foodstuff (gluten > 20 ppm) the amount of gluten was almost exclusively in the range of a very low gluten content. Contaminated products most commonly belonged to oats-, buckwheat-, and lentils-based items. Certified and higher cost gluten-free products were less commonly contaminated by gluten. CONCLUSION: Gluten contamination in either naturally or labeled gluten-free products marketed in Italy is nowadays uncommon and usually mild on a quantitative basis. A program of systematic sampling of gluten-free food is needed to promptly disclose at-risk products.

Importance of the combined urinary procedure for the diagnosis of Mucopolysaccharidoses.

BACKGROUND: Mucopolysaccharidoses are characterized by the accumulation of undegraded glycosaminoglycans in lysosomes in multiple organs and by their excretion in high amounts in urine. The aim of this study is to determine if this simple, reliable and reproducible method is useful for the diagnosis of Mucopolysaccharidoses. METHODS: The study included 2154 normal urine samples and 210 samples from 73 patients affected by different types of Mucopolysaccharidoses. The glycosaminoglycans were quantified by a dimethylmethylene blue method and size-fractionated by a modified one-dimensional electrophoresis method. RESULTS: The combination of the two methods allowed to identify all the patients affected by the different types of Mucopolysaccharidosis with 100% sensitivity and specificity. CONCLUSION: This combined approach gives fast diagnostic orientation about the different types of Mucopolysaccharidoses, offering an important tool for a better understanding of diagnosis and patient management.

Total and single species of uronic acid-bearing glycosaminoglycans in urine of newborns of 2-3days of age for early diagnosis application.

BACKGROUND: Urine are easily accessible and relatively simple to process and uronic acid-bearing glycosaminoglycans (UA-GAGs) may serve as biomarkers for several diseases, like for mucopolysaccharidosis. METHODS: We report a study from a large cohort of healthy newborns of 2-3days to have a basic profile of total content of urinary UA-GAGs, their composition and structural signatures utilizing a rapid extractive method and sensitive separation of enzymatic released disaccharides by capillary electrophoresis-light induced fluorescence. Results were also compared with those obtained from normal adult subjects. RESULTS: A total of UA-GAGs content of ~35µg/mg creatinine was observed in 331 newborns versus 1.5µg/mg creatinine of adult urine composed of ~90% chondroitin sulfate (CS), ~7% heparan sulfate (HS) and ~3% hyaluronic acid (HA). No significant differences were observed with adults. Specific ratios between the main CS disaccharides were informative of a significant greater 4-sulfation and charge density for newborn compared to adults. The HS from newborn urine was mainly composed by the non-sulfated (~64%) and mono-sulfated (~28%) disaccharides. No significant differences were observed versus adult urine. CONCLUSIONS: The present method is able to measure changes in UA-GAG composition and their structure independently of the age of subjects and rapidly applicable to the newborn diagnosis without necessity to have creatinine levels. Moreover, modifications in charge density values as well as the presence of sulfate groups in specific positions may be indicative of altered conditions.

Metabolic fate of milk glycosaminoglycans in breastfed and formula fed newborns.

In this study, the content, structure and residual percentages of glycosaminoglycans (GAGs) in the feces of seven breastfed newborns after ingesting a known amount of milk were studied. A comparison was made with five newborns fed with formula milk. Characterization of GAGs from milk and feces samples was performed according to previous methodology. Compared to the ingested GAGs present in milk, residual feces GAGs of breastfed newborns were <0.4 %, contrary to formula milk fed children, where the residues were ~4 %. As a consequence, >99 % of human milk GAGs are utilized as opposed to ~96 % of formula milk. Hyaluronic acid utilization was found to be fairly similar contrary to chondroitin sulfate/dermatan sulfate and heparan sulfate, which were found to be ~10-18 times lower in formula milk fed children. Our new results further demonstrate that the elevated content of human milk GAGs passes undigested through the entire digestive system of newborns, possibly protecting the infant from infections. In the distal gastrointestinal tract, these complex macromolecules are catabolized by a cohort of bacterial enzymes and constituent monosaccharides/oligosaccharides utilized for further metabolic purposes potentially useful for bacteria metabolism or internalized by intestinal cells. Thanks to their elevated structural heterogeneity, milk GAGs are used differently depending on their distinct primary structure. Finally, a different utilization and availability was observed for human milk GAGs compared to formula milk due to their various composition and structural heterogeneity.