Study Title:

Gut Flora Following Birth Influences Celiac, Breast Feeding Helpful

Study Abstract

Celiac disease (CD) is an immune-mediated enteropathy involving genetic and environmental factors whose interaction might influence disease risk. The aim of this study was to determine the effects of milk-feeding practices and the HLA-DQ genotype on intestinal colonization of Bacteroides species in infants at risk of CD development. This study included 75 full-term newborns with at least one first-degree relative suffering from CD. Infants were classified according to milk-feeding practice (breast-feeding or formula feeding) and HLA-DQ genotype (high or low genetic risk). Stools were analyzed at 7 days, 1 month, and 4 months by PCR and denaturing gradient gel electrophoresis (DGGE). The Bacteroides species diversity index was higher in formula-fed infants than in breast-fed infants. Breast-fed infants showed a higher prevalence of Bacteroides uniformis at 1 and 4 months of age, while formula-fed infants had a higher prevalence of B. intestinalis at all sampling times, of B. caccae at 7 days and 4 months, and of B. plebeius at 4 months. Infants with high genetic risk showed a higher prevalence of B. vulgatus, while those with low genetic risk showed a higher prevalence of B. ovatus, B. plebeius, and B. uniformis. Among breast-fed infants, the prevalence of B. uniformis was higher in those with low genetic risk than in those with high genetic risk. Among formula-fed infants, the prevalence of B. ovatus and B. plebeius was increased in those with low genetic risk, while the prevalence of B. vulgatus was higher in those with high genetic risk. The results indicate that both the type of milk feeding and the HLA-DQ genotype influence the colonization process of Bacteroides species, and possibly the disease risk.

From press release:

The autoimmune condition, Celiac disease, afflicts roughly one in 133 Americans. It is caused by a combination of genetic and environmental factors. Now a team of investigators from Spain shows that the level of genetic risk of celiac disease influences the composition of infants' gut microbiota, and confirms earlier studies showing that the type of milk feeding -- breast vs. formula -- also influences the species distribution. Their hypothesis is that these changes in the intestinal microbiota may directly influence the risk of celiac disease, and that if this is so, changes in diet -- particularly breast feeding -- could reduce that risk.

The research is published in the August 2011 issue of the journal Applied and Environmental Microbiology.

The newborn intestine is colonized immediately after birth by microorganisms from the mother and the environment. Earlier research had shown that breast feeding protects against celiac disease as compared to formula feeding, as well as that the intestinal microbiota is less diverse in breast- than in formula-fed infants, with different genera predominating in each. The new research also shows that infants at high genetic risk of celiac disease have a high prevalence of certain Bacteroides spp that is different from the population in those at low genetic risk.

The investigators report further that the type of milk influences Bacteroides species composition, in particular with breast feeding favoring the prevalence of B. uniformis, a species associated with the low risk genotype, and reducing differences in Bacteroides species composition between the two genetic risk groups. "Altogether, this could explain the protective role that breast-feeding plays against development of celiac disease, as reported in previous observational studies," says principal investigator Yolanda Sanz of the Instituto de Agroquimica y Tecnologia de Alimentos, Valencia, Spain.

If associations between the composition of the gut microbiota, the genotype, and incidence of celiac disease are confirmed, "We will be able to recommend breastfeeding, and propose dietary intervention trials to modulate the intestinal microbiota in subjects at risk of developing celiac disease, in order to try to prevent its development," says Sanz.

The study includes 75 full term infants, all with at least one first degree relative suffering from celiac disease, but who had varying degrees of genetic risk. In the study, the researchers sorted the infants into two groups according to genetic risk, a high-risk (7-28 percent) group, and a low-risk (less than one percent) group. They plan to follow the infants long enough to determine who gets the disease, which will shed further light on whether the intestinal flora influence risk.

Study Information

E. Sanchez, G. De Palma, A. Capilla, E. Nova, T. Pozo, G. Castillejo, V. Varea, A. Marcos, J. A. Garrote, I. Polanco, A. Lopez, C. Ribes-Koninckx, M. D. Garcia-Novo, C. Calvo, L. Ortigosa, F. Palau, Y. Sanz
Influence of Environmental and Genetic Factors Linked to Celiac Disease Risk on Infant Gut Colonization by Bacteroides Species.
Applied and Environmental Microbiology
2011 August
Instituto de Agroquimica y Tecnologia de Alimentos, Valencia, Spain.

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