Current Advances in Structure–Function Relationships and Dose-Dependent Effects of Human Milk Oligosaccharides

Abstract

HMOs (human milk oligosaccharides) are the third most important nutrient in breast milk. As complex glycans, HMOs play an important role in regulating neonatal intestinal immunity, resisting viral and bacterial infections, displaying antiinflammatory characteristics, and promoting brain development. Although there have been some previous reports of HMOs, a detailed literature review summarizing the structure−activity relationships and dose-dependent effects of HMOs is lacking. Hence, after introducing the structures and synthetic pathways of HMOs, this review summarizes and categorizes identified structure− function relationships of HMOs. Differential mechanisms of different structural HMOs utilization by microorganisms are summarized. This review also emphasizes the recent advances in the interactions between different health benefits and the variance of dosage effect based on in vitro cell tests, animal experiments, and human intervention studies. The potential relationships between the chemical structure, the dosage selection, and the physiological properties of HMOs as functional foods are vital for further understanding of HMOs and their future applications.

Patterns of Human Milk Oligosaccharides in Mature Milk Are Associated with Certain Gut Microbiota in Infants

“…In terms of nongenetic factors, the stage of milk maturation is one of the most important influencing factors. Previous studies have reported that the total concentration of HMOs in mature milk was approximately 5-20 g/L [34][35][36][37][38]. In our study, the mean of total concentration of HMOs was consistent with previous reports.…”

Influence of microbially fermented 2´-fucosyllactose on neuronal-like cell activity in an in vitro co-culture system

“…Furthermore, in germ-free mice orally fed with 13 C-labeled 2´-FL, the 13 C bolus remains in the intestinal content and was expelled via the feces, indicating that gut microbial metabolites of 2´-FL or Fuc could be responsible for the observed effects since 13 C enrichment of brain tissue occurred when the 13 C-2´-FL or 13 C-Fuc bolus had reached the lower gut containing microbiota (28,29). In this context, it is wellknown that bifidobacteria were able to utilize fucosylated HMOs to produce metabolites such as short-chain fatty acids (e.g., acetate) and lactate (72)(73)(74). During breastfeeding, B. longum ssp.…”

2′-Fucosyllactose alleviates OVA-induced food allergy in mice by ameliorating intestinal microecology and regulating the imbalance of Th2/Th1 proportion

“…[16][17][18] Previous studies found that 2′-FL modulated the gut microbiota in a structure-dependent manner. 19 2′-FL binds with histo-blood group antigens (HBGAs) or soluble receptors on the intestinal epithelium to recognize or prevent pathogenic bacteria and parasites as an antiadhesive antimicrobial and pathogen decoy receptor. On the other hand, probiotics dominate the infant gut microbiota during breastfeeding via producing transport proteins and intracellular/extracellular glycosidase, which directly participate in the utilization of 2′-FL.…”