Association between sn-2 fatty acid profiles of breast milk and development of the infant intestinal microbiome

Abstract

Increasing evidence shows that host diet and gut microbes are related. Previous studies have shown the effects of specific dietary fatty acids (FAs) on intestinal microbiota, but little is known about the effect of the stereospecifically numbered sn-2 position in triglycerides (TG) of human milk on the gut microbiome of infants. This study aimed at examining possible effects of sn-2 FAs of human milk on the gut microbial development of breastfeeding babies. Sn-2 FAs and intestinal microbiota were assessed by GC-MS and high-throughput 16S rRNA sequencing, respectively. The results showed that breast milk from mothers in China contained ten major sn-2 FAs dominated by palmitic acid (C, 54.42%), oleic acid (C n-9, 14.95%), linoleic acid (LA, C n-6, 12.81%), myristic acid (C, 4.50%) and C (3.17%). Total long chain unsaturated fatty acids (LCUFA) decreased from colostrum to mature milk, while total saturated fatty acids (SFA) showed no significant difference during lactation. A significant association between sn-2 FAs in milk and infant gut microbiota was found between decanoic acid (C), myristic acid (C), stearic acid (C), C, arachidonic acid (AA, C n-6), docosahexaenoic acid (DHA, C n-3) with Bacteroides, Enterobacteriaceae, Veillonella, Streptococcus, and Clostridium. These microbes were involved in short-chain fatty acid (SCFA) production and other functions, and significantly increased at 13-15 d after breastfeeding was initiated. C and DHA were relevant to most of the microbes. This study demonstrated the relatively steady profiles of sn-2 FAs in breast milk and gut microbiota of infants, together with their correlation during the breastfeeding period. The above results provided important information for designing the configuration of FAs in next-generation formulas for Chinese infants.

Breast Milk Lipids and Fatty Acids in Regulating Neonatal Intestinal Development and Protecting against Intestinal Injury

“…Compared to sn-1,3 palmitic acids of triglycerides, sn-2 palmitic acids resulted in decreased intestinal injury and inflammation by upregulation of PPAR-γ, antioxidant enzymes (superoxide dismutase, glutathione peroxidase), and induction of an immunosuppressive T-regulatory cell response [43]. These data support the role of the saturated fatty acid, palmitic acid, specifically in sn-2 configuration, as being important for intestinal mucosal homeostasis, gut microbiome, and immune response [44]. However, the lack of evidence in clinical trials to establish a cause and effect relationship between the palmitic acid at sn-2 position and neonatal health outcomes, led the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition to recommend that the inclusion of high sn-2 palmitic acid cannot be considered essential in human infant formula [45,46].…”

Innate Immune Responses and Gut Microbiomes Distinguish HIV-Exposed from HIV-Unexposed Children in a Population-Specific Manner

“…Abundances of SCFA-producing bacteria were reduced in Canadian HEU children compared with Canadian HUU children. We found that gut microbiomes of Canadian HEU children had lower relative abundances of SCFA-producing taxa that have been isolated from breast milk and are associated with breastfeeding-Bifidobacterium and Veillonella (36,37). As well, other prominent SCFA producers normally present in adult microbiomes, Ruminococcus, Lachnospira, Clostridia, Faecalibacterium, and Roseburia (38), were also less abundant in Canadian HEU children.…”

Shaping the Gut Microbiota by Breastfeeding: The Gateway to Allergy Prevention?

“…They are detergents for bacteria explaining, at least in part, the low bacterial count in the duodenum where bile acids are mostly released. Human milk fatty acid profiles were associated with the relative abundance of five taxa ( Bacteroides , Enterobacteriaceae, Veillonella, Streptococcus , and Clostridium ) in the gut microbiota of breastfed neonates (97).…”