Scientists from the Universidad Complutense de Madrid and Probisearch S.L.U. in Spain report that supplementation with Bifidobacterium longum subsp. infantis R0033, Lactobacillus helveticus R0052 or Bifidobacterium bifidum R0071 led to shifts in the gut microbiomes of healthy infants to that of a younger (unweaned) infant.
“High levels of bifidobacteria in the infant gut have been associated with timely and appropriate development and maturation of the immune system,” wrote the researchers in the journal Beneficial Microbes.
“Our results may be a starting point to understand why different probiotic strains may modulate the microbiota composition and the immune system associated to the gastrointestinal tract of infants during their first year of life.”
The infant microbiome
Attention is increasing on how the microbiome develops during the first 1,000 days of life. It is well reported that the gut microbiome of a baby delivered vaginally is different from that of a baby delivered via C-section. Feeding also impacts the microbiome with the gut microbiome of breast-fed babies different to formula-fed babies.
The new study examined how the gut microbiota composition and fecal immune compounds could be impacted by probiotic strains over an eight-week period.
“The effect of probiotic strains on the gut microbial composition and immune parameters has been widely studied in children with health issues such as allergy, colics, celiac disease or preterm infants,” explained the researchers. “However, few studies have focused on healthy infants and to our knowledge none have used 16S rDNA sequencing or studied such a wide range of immune compounds.”
Study details
The researchers recruited 202 healthy infants to participate in their study. The infants were aged between three and 12 months and included both breastfed and/or formula fed infants.
Data showed that the most abundant genus in all four groups of infants before and after intervention was Bifidobacterium (approximately 50% of the sequences). While no significant changes in composition were observed in the probiotic groups, the placebo group displayed decreases in different Bifidobacterium species, including B. bifidum and B. breve. In addition, Bacteroides, Blautia, Clostridium, Coprococcus and Faecalibacterium genera increased in the placebo group.
Immune factors measured in fecal samples showed that infants in the B. infantis R0033 group experienced increases in the anti-inflammatory ratio of interleukin (IL)-10 to IL-12, while infants in the L. helveticus R0052 group experienced increases in the pro-inflammatory ratio of TNF-alpha to IL-10. This latter effect was also recorded in the placebo group.
“In conclusion, the species profile of the microbiome observed in all three probiotic groups resembled that of a younger infant, similar to an unweaned infant, when compared to the placebo group which may also be related with an anti-inflammatory effect,” wrote the researchers.
Source: Beneficial Microbes
Volume 9, Number 4, Pages: 573 – 584, doi: 10.3920/BM2017.0132
“Modulatory effect of three probiotic strains on infants’ gut microbial composition and immunological parameters on a placebo-controlled, double-blind, randomised study”
Authors: J. De Andrés et al.