Low-Protein Infant Formula Enriched with Alpha-Lactalbumin during Early Infancy May Reduce Insulin Resistance at 12 Months: A Follow-Up of a Randomized Controlled Trial.

High protein intake during infancy results in accelerated early weight gain and potentially later obesity. The aim of this follow-up study at 12 months was to evaluate if modified low-protein formulas fed during early infancy have long-term effects on growth and metabolism. In a double-blinded RCT, the ALFoNS study, 245 healthy-term infants received low-protein formulas with either alpha-lactalbumin-enriched whey (α-lac-EW; 1.75 g protein/100 kcal), casein glycomacropeptide-reduced whey (CGMP-RW; 1.76 g protein/100 kcal), or standard infant formula (SF; 2.2 g protein/100 kcal) between 2 and 6 months of age. Breastfed (BF) infants served as a reference. At 12 months, anthropometrics and dietary intake were assessed, and serum was analyzed for insulin, C-peptide, and insulin-like growth factor 1 (IGF-1). Weight gain between 6 and 12 months and BMI at 12 months were higher in the SF than in the BF infants (p = 0.019; p < 0.001, respectively), but were not significantly different between the low-protein formula groups and the BF group. S-insulin and C-peptide were higher in the SF than in the BF group (p < 0.001; p = 0.003, respectively), but more alike in the low-protein formula groups and the BF group. Serum IGF-1 at 12 months was similar in all study groups. Conclusion: Feeding modified low-protein formula during early infancy seems to reduce insulin resistance, resulting in more similar growth, serum insulin, and C-peptide concentrations to BF infants at 6-months post intervention. Feeding modified low-protein formula during early infancy results in more similar growth, serum insulin, and C-peptide concentrations to BF infants 6-months post intervention, probably due to reduced insulin resistance in the low-protein groups.

Degree of hydrolysis is a poor predictor of the sensitizing capacity of whey- and casein-based hydrolysates in a Brown Norway rat model of cow's milk allergy.

The use of infant formulas (IFs) based on hydrolyzed cow's milk proteins to prevent cow's milk allergy (CMA) is highly debated. The risk of sensitization to milk proteins induced by IFs may be affected by the degree of hydrolysis (DH) as well as other physicochemical properties of the cow's milk-based protein hydrolysates within the IFs. The immunogenicity (specific IgG1 induction) and sensitizing capacity (specific IgE induction) of 30 whey- or casein-based hydrolysates with different physicochemical characteristics were compared using an intraperitoneal model of CMA in Brown Norway rats. In general, the whey-based hydrolysates demonstrated higher immunogenicity than casein-based hydrolysates, inducing higher levels of hydrolysate-specific and intact-specific IgG1. The immunogenicity of the hydrolysates was influenced by DH, peptide size distribution profile, peptide aggregation, nano-sized particle formation, and surface hydrophobicity. Yet, only the surface hydrophobicity was found to affect the sensitizing capacity of hydrolysates, as high hydrophobicity was associated with higher levels of specific IgE. The whey- and casein-based hydrolysates exhibited distinct immunological properties with highly diverse molecular composition and physicochemical properties which are not accounted for by measuring DH, which was a poor predictor of sensitizing capacity. Thus, future studies should consider and account for physicochemical characteristics when assessing the sensitizing capacity of cow's milk-based protein hydrolysates.

Low-Protein Formulas with Alpha-Lactalbumin-Enriched or Glycomacropeptide-Reduced Whey: Effects on Growth, Nutrient Intake and Protein Metabolism during Early Infancy: A Randomized, Double-Blinded Controlled Trial.

Protein intake is higher in formula-fed than in breast-fed infants during infancy, which may lead to an increased risk of being overweight. Applying alpha-lactalbumin (α-lac)-enriched whey or casein glycomacropeptide (CGMP)-reduced whey to infant formula may enable further reduction of formula protein by improving the amino acid profile. Growth, nutrient intake, and protein metabolites were evaluated in a randomized, prospective, double-blinded intervention trial where term infants received standard formula (SF:2.2 g protein/100 kcal; n = 83) or low-protein formulas with α-lac-enriched whey (α-lac-EW;1.75 g protein/100 kcal; n = 82) or CGMP-reduced whey (CGMP-RW;1.76 g protein/100 kcal; n = 80) from 2 to 6 months. Breast-fed infants (BF; n = 83) served as reference. Except between 4 and 6 months, when weight gain did not differ between α-lac-EW and BF (p = 0.16), weight gain was higher in all formula groups compared to BF. Blood urea nitrogen did not differ between low-protein formula groups and BF during intervention, but was lower than in SF. Essential amino acids were similar or higher in α-lac-EW and CGMP-RW compared to BF. Conclusion: Low-protein formulas enriched with α-lac-enriched or CGMP-reduced whey supports adequate growth, with more similar weight gain in α-lac-enriched formula group and BF, and with metabolic profiles closer to that of BF infants.

Partially Hydrolysed Whey Has Superior Allergy Preventive Capacity Compared to Intact Whey Regardless of Amoxicillin Administration in Brown Norway Rats.

Background: It remains largely unknown how physicochemical properties of hydrolysed infant formulas influence their allergy preventive capacity, and results from clinical and animal studies comparing the preventive capacity of hydrolysed infant formula with conventional infant formula are inconclusive. Thus, the use of hydrolysed infant formula for allergy prevention in atopy-prone infants is highly debated. Furthermore, knowledge on how gut microbiota influences allergy prevention remains scarce. Objective: To gain knowledge on (1) how physicochemical properties of hydrolysed whey products influence the allergy preventive capacity, (2) whether host microbiota disturbance influences allergy prevention, and (3) to what extent hydrolysed whey products influence gut microbiota composition. Methods: The preventive capacity of four different ad libitum administered whey products was investigated in Brown Norway rats with either a conventional or an amoxicillin-disturbed gut microbiota. The preventive capacity of products was evaluated as the capacity to reduce whey-specific sensitisation and allergic reactions to intact whey after intraperitoneal post-immunisations with intact whey. Additionally, the direct effect of the whey products on the growth of gut bacteria derived from healthy human infant donors was evaluated by in vitro incubation. Results: Two partially hydrolysed whey products with different physicochemical characteristics were found to be superior in preventing whey-specific sensitisation compared to intact and extensively hydrolysed whey products. Daily oral amoxicillin administration, initiated one week prior to intervention with whey products, disturbed the gut microbiota but did not impair the prevention of whey-specific sensitisation. The in vitro incubation of infant faecal samples with whey products indicated that partially hydrolysed whey products might confer a selective advantage to enterococci. Conclusions: Our results support the use of partially hydrolysed whey products for prevention of cow's milk allergy in atopy-predisposed infants regardless of their microbiota status. However, possible direct effects of partially hydrolysed whey products on gut microbiota composition warrants further investigation.

Preclinical Brown Norway Rat Models for the Assessment of Infant Formulas in the Prevention and Treatment of Cow's Milk Allergy.

BACKGROUND: Infant formulas (IFs) based on hydrolysed cow's milk proteins are central in the management of cow's milk allergy (CMA) in infants and small children. New IF compositions with improved prevention and treatment properties are needed, along with appropriate preclinical animal models, to evaluate these properties before introduction into humans. OBJECTIVES: We aimed to develop preclinical models for the assessment of the primary preventive and desensitising capacity of cow's milk IF in allergy-prone, high-IgE responder Brown Norway rats. METHOD: Preventive capacity was assessed in cow's milk-naïve rats given a 2- or 4-week regimen of whey-based extensively hydrolysed IF (eHF), partially hydrolysed IF (pHF), or intact ß-lactoglobulin (BLG) ad libitum in drinking bottles, followed by intraperitoneal (i.p.) immunisation with BLG. Desensitising capacity was assessed in orally BLG-sensitised rats after a 3- or 6-week regimen of eHF, pHF, or intact BLG administration in drinking bottles, followed by i.p. challenge with BLG. Primary preventive and desensitising capacity were analysed by serum BLG-specific IgG1 and IgE. RESULTS: The preventive regimens did not induce detectable BLG-specific IgG1 or IgE in cow's milk-naïve rats. A preventive regimen consisting of pHF or BLG, but not eHF, induced complete tolerance to BLG, as demonstrated by the absence of BLG-specific IgE following i.p. immunisation. Desensitising regimens had a limited effect on BLG-specific IgG1 or IgE when comparing sensitised rats before and after treatment. Challenge with BLG (i.p.) increased BLG-specific IgE in all treatment regimens except for in the BLG group, suggesting a limited desensitising capacity of IF based on hydrolysates and a need for the presence of intact allergen for desensitisation. CONCLUSIONS: The presented models highlight that different mechanisms are at play in the induction of de novo tolerance to cow's milk proteins and the desensitisation of CMA. Different IF products may be needed for the primary prevention and treatment of CMA.

Osteopontin Levels in Human Milk Vary Across Countries and Within Lactation Period: Data From a Multicenter Study.

OBJECTIVES: Osteopontin (OPN) is a multifunctional protein expressed in many cell types, tissues and body fluids with the highest concentrations found in milk; significantly higher in human than in bovine milk. Intervention studies have indicated beneficial effects of supplementing infant formula with bovine OPN. In this multicenter study, we determined the OPN content in human milk samples from 629 Chinese, Danish, Japanese and Korean mothers. METHODS: At each study site, milk samples were collected and analyzed for OPN and protein concentration using ELISA and infrared spectroscopy, respectively. RESULTS: A total of 829 milk samples from 629 women were included. When delivering the first sample, mean maternal age was 31.4 years (SD 4.0), and median infant age was 13.4 weeks (interquartile range 4.6-17.9). The median OPN concentration varied across sites; from 99.7 mg/L in Danish, 185.0 mg/L in Japanese, 216.2 mg/L in Korean to 266.2 mg/L in Chinese mothers (P < 0.001), corresponding to 1.3%, 2.4%, 1.8% and 2.7% of the total protein content (OPN/protein%) (P < 0.05), respectively. Based on 75 Chinese and 33 Japanese mothers delivering more than 1 sample, multilevel (mixed model) linear regression analysis showed a decrease in OPN concentration with infant age (ß = (-11.3), 95% confidence interval (CI) = (-13.9) to (-8.8) and ß = (-2.1), 95% CI = (-3.2) to (-0.9), respectively). CONCLUSIONS: In this large multicenter study, we observed statistically significant differences in the OPN concentration and the OPN/protein% in human milk samples between countries. Based on mothers delivering more than 1 sample, a significant decrease within the lactation period was observed.

Breastfeeding, Infant Formula, and Introduction to Complementary Foods-Comparing Data Obtained by Questionnaires and Health Visitors' Reports to Weekly Short Message Service Text Messages.

BACKGROUND: Studies on prevalence and effects of breastfeeding call for reliable and precise data collection to optimize infant nutrition, growth, and health. Data on breastfeeding and infant nutrition are at risk of, for example, recall bias or social desirability bias. OBJECTIVE: The aim of the present analysis was to compare data on infant nutrition, that is, breastfeeding, use of infant formula, and introduction to complementary foods, obtained by four different methods. We assumed that weekly short message service (SMS) questions were the most reliable method, to which the other methods were compared. DESIGN: The study population was part of the Odense Child Cohort. The four methods used were: (a) self-administered questionnaire 3 months postpartum, (b) self-administered questionnaire 18 months postpartum, (c) registrations from health visitors visiting the families several times within the first year of life, and (d) weekly SMS questions introduced shortly after birth. RESULTS: In total, 639 singleton mothers with data from all four methods were included. The proportion of mothers initiating breastfeeding varied from 86% to 97%, the mean duration of exclusive breastfeeding from 12 to 19 weeks, and the mean age when introduced to complementary foods from 19 to 21 weeks. The mean duration of any breastfeeding was 33 weeks across methods. CONCLUSIONS: Compared with the weekly SMS questions, the self-administered questionnaires and the health visitors' reports resulted in a greater proportion of mothers with an unknown breastfeeding status, a longer duration of exclusive breastfeeding and later introduction to complementary foods, while the duration of any breastfeeding did not differ.