Molecular Fingerprints of the Human Fecal Microbiota From 9 to 18 Months Old and the Effect of Fish Oil Supplementation
ABSTRACT The aim of this study was to monitor changes in the fecal microbiota from 9 to 18 months and to investigate the effect of increasing dietary n-3 polyunsaturated fatty acids on the fecal microbiota.
In a double-blind controlled trial with random allocation to daily supplementation with 5 mL of fish oil (FO) or sunflower oil (SO) from 9 to 18 months of age, stool samples were collected from 132 healthy Danish infants. Molecular fingerprints of the bacterial DNA were obtained by terminal restriction fragment length polymorphism (T-RFLP).
The T-RFLP profiles indicated that a few T-RFs became dominant with age (bp100 and 102, both presumed to be Bacteroidetes) concomitantly with an overall increase in the microbial diversity (P = 0.04). Breast-feeding influenced both the T-RFLP profiles at 9 months and the changes from 9 to 18 months, and breast-feeding cessation during the trial modified the response to the dietary oils. In the FO group, the increase in bp102 was significantly reduced among children weaned before compared with those weaned during the trial (P = 0.027), whereas the increase in bp100 was reduced in the preweaned children of the SO group relative to those weaned during the trial (P = 0.004). This was supported by intervention group differences in the changes in bp102 and bp100 among the earlier weaned children (P = 0.06 and P = 0.09, respectively).
Cessation of breast-feeding played a dominant role relative to developmental changes in the fecal microbiota from 9 to 18 months. FO compared with SO supplementation affected changes in large bacterial groups, but only among children who had stopped breast-feeding before 9 months of age.
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ABSTRACT: Even though the Pacific white shrimp is a very important culture species, there is little information on the effect of feed nutrients on the intestinal microbiota. In shrimp, dietary fatty acids largely affect the growth and immune system of Litopenaeus vannamei in part by changing the intestinal bacterial profile. Therefore, an Illumina-based sequencing method was used to examine the intestinal bacterial composition of L. vannamei following six diets with different lipid sources. The bacterial communities in the culture water and shrimp intestinal contents were also compared. The results revealed that shrimp fed a diet with an equal combination of soybean oil, beef tallow, and linseed oil (SBL) had significantly higher weight gain and survival rate than those fed with soybean oil or beef tallow. Proteobacteria and Tenericutes were dominant in the intestines of L. vannamei regardless of the diet. There was a significant prevalence of Rhizobiaceae in shrimp fed the SBL diet than in shrimp fed diets with soybean oil or beef tallow. Proteobacteria dominated in both the culture water and shrimp intestinal samples of L. vannamei. These results suggest that the host intestinal environment imposes selective pressure on the establishment of microbial communities. Lipid sources with different fatty acid compositions could affect the composition of the intestinal microbiota of L. vannamei.Aquaculture 10/2014; 434:449–455. DOI:10.1016/j.aquaculture.2014.09.008 · 1.83 Impact Factor
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ABSTRACT: We investigated whether n-3LCPUFA affected immune function in late infancy and explored effect-modification by single nucleotide polymorphisms (SNPs) and links to intestinal microbiota. Infants (n=105) were randomized to fish oil (FO, 1.2 g/d n-3LCPUFA) or sunflower oil (SO)-supplements from age 9–18 months. Immune function was assessed by ex vivo cytokine production in stimulated blood and plasma immunoglobulinE (IgE). We genotyped functional SNPs in PPARG2 and COX2 and analyzed fecal microbiota by 16 S-rRNA terminal restriction fragment length polymorphism. FO compared to SO reduced L. paracasei-stimulated IL-6 at 18 months (P=0.03, n=104). This effect was most pronounced among infants wild-type for PPARG2-Pro12Ala and/or COX2-T8473C (P<0.05). Predominant bacterial fragments were associated with 18 months IgE in all infants (P=0.004) (bp100) and with IL-6 production among infants weaned before 9 months (P=0.047) (bp102). Thus, FO reduced IL-6 in a genotype-modified manner. The microbiota was partly linked to IL-6 and IgE, not directly to FO.Prostaglandins Leukotrienes and Essential Fatty Acids 11/2014; 94. DOI:10.1016/j.plefa.2014.10.007 · 1.98 Impact Factor
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ABSTRACT: Patients with inflammatory bowel disease (IBD) have an increased risk of 10%-15% developing colorectal cancer (CRC) that is a common disease of high economic costs in developed countries. the CRC has been increasing in recent years and its mortality rates are very high. Multiple biological and biochemical factors are responsible for the onset nad progression of this pathology. moreover, it appears absolutely necessary to investigate the environmental factors favoring the onset of CRC and the production of colonic healt. the gut microflora, or microbiota, has an extensive diversity both quantitatively and qualitatively. in utero, the intestine of the mammalian fetus is sterile. Al birth, the intestinal microbiota in acquired by ingestion maternal anal or vaginal organisms, ultimately developing into a stable community, with marked variations in microbial composition between individuals. the development of IBD is often associated with qualitative and quantitative disorders of the intestinal microbial flora (dysbiosis). the healthy human gut arbours about 10 different bacterial species distributed in colony forming units which colonize the gastrointestinal tract. The intestinal microbiota plays a fundamental role in helath and the progeression of diseases such as IBD and CRC. in Healthy subjects, the main control of intestinal bacterial colonization occurs through gastric acidity but other factors such as endoluminal temperature, competition between different bacterial strains, peristalsis and drugs can influence the intestinal microenvironment. the microbiota exerts diverse physiological functions to include; growth inhibition of pathogenic microrganisms, synthesis of compounds useful for the trophysm of colonic mucosa, regulation of the intestinal lymphoid tissue and synthesis of amino acids. furthermopre, mucus seems to play an important role in protecting the intestinal mucosa and maintaining its integrity. changes in the microbiota composition are mainly influenced by diet and age, as well as genetic factors. Increasing evidence indicates that dysbiosis favors the production of genotoxins and metabolities associated with carcinogeneasis and induces dysregulation of the immune response wich promotes and sustains inflammation in IBD leading to carcinogenesis. a disequilibrium in gut microflora composition leads to the specific activation of gut associated lymphoid tissue. the associated chronic inflammatory process associated increases the risk of developing CRC. Ulcerative colitis and Crohn's diasease are the two major IBDs characterized by an early onset and extraintestinal manifestations, such as rheumatoid arthtritis. the pathogenesis of both diseases is complex and not yet fully known. however, it is widely accepted that an inappropriate immune response to microbial flora can play a pivotal role in IBD pathogenesis.