Writing Exercise #7

Diet: Pregnancy imposes changes in the bacterial composition of pregnant women. In the article “Pregnancy-related changes in the maternal gut microbiota are dependent upon the mother’s periconceptional diet”, the authors did a study about diet and pregnancy interaction, high-fat diet intake before and during pregnancy leads typical shifts in the pregnant gut microbiota. This causes the major differences in the abundance of genes related to lipid metabolism, gluconeogenic and glycolysis metabolic pathways during pregnancy period. In the infants, the transition from milk to solid food changes in their microbial population and species. The infant’s gut microbiota has an abundance of Bacteroidetes and Firmicutes same as adults’ microbiota [4].

Antibiotic use: the antibiotic use cause change in maternal microbiota and abundance of some taxonomic groups. The use of B antibiotic including azithromycin, amoxicillin, and cefaclor triggers the increase of Proteobacteria and Enterobacter and decrease of Firmicutes and Lactobacillus [1]. Besides, similar effects with normal people, antibiotic contributes in reducing bacterial diversity in the gut microbiota of pregnant women. Antibiotic also causes weight gain [4]

Probiotic use: the pregnant women who used probiotics 14 days before C-section showed modulation of the infant microbiota as well as offspring’s microbiota. The probiotic treatments on pregnant women gave advantages to the offspring to have the immune system to respond to pathogens and commensal after birth and reduce the risk of eczema as well. The immune modulation affects the microbial components.

Mode of delivery: The gut microbiota of infants has a relationship with mode of delivery [3]. The gut microbiota of vaginally born infant is colonized by bacteria from maternal vagina including the enrichment in the Prevotella, Sneathia, and Lactobacillus group which is a positive factor to infant microbiota [2]. The infant born by C- section has delayed colonization of the phylum Bacteroidetes and alpha diversity during first 2 years of life. Also, the infant born by C-section has higher number of antibiotic-resistance genes compared with infants born vaginally [4]

The method of infant feedings: There are differences in gut microbiota between breastfed infants and formula-fed infant. The major organism in breastfed infant is Bifidobacteria while the formula-fed infants have Enterococci and Clostridia mostly. Besides, the breastfed infants have more bacterial cells and less species diversity. The methods of feeding have effects on infant’s oral microbiome also. The study shows that the three-month-old breastfed infants consist of oral lactobacilli with antimicrobial properties which didn’t appear in formula-fed infants [4].

Sources:

Gonzalez-Perez G., Hicks A. L., Tekieli T. M., Radens C. M., Williams B. L., Lamouse-Smith E. S. 2016. Maternal antibiotic treatment impacts development of the neonatal intestinal microbiome and antiviral immunity. J. Immunol. 196, 3768–3779. 10.4049/jimmunol.1502322

Jakobsson H. E., Abrahamsson T. R., Jenmalm M. C., Harris K., Quince C., Jernberg C., et al. . (2014). Decreased gut microbiota diversity, delayed Bacteroidetes colonisation and reduced Th1 responses in infants delivered by caesarean section. Gut 63, 559–566. 10.1136/gutjnl-2012-303249

Khan I., Azhar E. I., Abbas A. T., Kumosani T., Barbour E. K., Raoult D., et al. . 2016. Metagenomic analysis of antibiotic-induced changes in gut microbiota in a pregnant rat model. Front. Pharmacol. 7:104. 10.3389/fphy.2016.00104

Sela D. A., Li Y., Lerno L., Wu S., Marcobal A. M., German J. B., et al. . (2011). An infant-associated bacterial commensal utilizes breast milk sialyloligosaccharides. J. Biol. Chem. 286, 11909–11918. 10.1074/jbc.M110.193359