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- Karlsson Videhult, Frida, 1980-
(author)
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Effects of early probiotic supplementation in a pediatric setting : Focus on body composition, metabolism and inflammation
- 2016
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Doctoral thesis (other academic/artistic)abstract
- We aimed to determine the short- and long-term effects on growth, body composition, metabolic and inflammatory markers following supplementation with the probiotic Lactobacillus paracasei ssp. paracasei F19 (LF19) during weaning. Methods: One-hundred and seventy-nine healthy, infants in Umeå city, Västerbotten County were randomised to daily intake of cereals with (n=89) or without (n=90) LF19 108 colony-forming units from 4 to 13 months of age. Weight, length, head circumference and body composition, assessed by skinfold thickness, were examined at 4, 5.5, 6.5, 9, 12 and 13 months of age. Venous blood was drawn at 5.5 and 13 months. In all, 171 infants completed the intervention and were invited to a follow-up at 8-9 years of age between 2009 and 2011, 120 children participated. Weight, height, sagittal abdominal diameter and body composition (using Dual Energy X-ray Absorptiometry-scan) were measured. Data on weight and height at 4 years were collected from medical records. The families filled out a 4-day food record and a food frequency questionnaire, physical activity was assessed using a pedometer for 7 days. At 5.5, 13 months and 8-9 years of age we analysed the serum blood lipid profile. At 8-9 years fasting glucose, insulin, aspartate and alanine transaminases were analysed in serum. Homeostatic Model Assessment index was calculated. At follow-up serum adiponectin, high-sensitivity C-reactive protein and plasma C-peptide, ghrelin, gastric inhibitory polypeptide, glucagon-like peptide 1, glucagon, insulin, leptin, plasminogen activator inhibitor-1, resistin and visfatin were analysed. For characterisation of the plasma metabolome, a subgroup (n=40) was analysed at 5.5 and 13 months of age by gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) analysis and in all (n=112) children at the follow-up using untargeted GC-GC/MS. Results: There were no differences between the LF19 and placebo group regarding body weight, length/height at any assessment from 4 months to 8-9 years of age; nor were there any differences between the groups in body composition. In the LF19 group 19 % were overweight/obese, the corresponding number was 21 % in the placebo group (p=0.78). Analysed metabolic and inflammatory markers, both during the intervention and the follow-up did not differ between the two groups. At 13 months of age lower levels of palmitic acid and palmitoleic acid (both p<0.04) and higher levels of putrescine (p<0.01) were seen in the LF19 compared to the placebo group. These differences did not persist at 8-9 years of age. At that age, we found statistically stronger models when comparing overweight/obese and normal weight children as well as in relation to sex. Conclusion: Early intervention with the probiotic LF19 at the time of weaning exerted transient effects on the metabolome. In a long-term perspective, we found neither benefit nor harm on growth, body composition, metabolic or inflammatory markers following supplementation with LF19 during weaning.
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- West, Christina, 1969-
(author)
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Feeding Lactobacillus paracasei ssp. paracasei strain F19 to infants during weaning : effects on adaptive immunity and gut microbial function
- 2008
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Doctoral thesis (other academic/artistic)abstract
- Introduction: Gut microbial composition has been associated with immune-mediated diseases. Breastfeeding yields a microbiota rich in bifidobacteria and promotes colonization by lactobacilli. Bifidobacteria and lactobacilli are considered health-promoting and are used as probiotics, i.e. live microbial food supplements which when ingested in adequate amounts confer a beneficial effect on the host. During weaning the developing gut immune system is exposed to an increasing variety of antigens from both foods and gut microbiota.Aims: We aimed to determine if daily feeding of 1x108 colony-forming units (CFU) of the probiotic Lactobacillus paracasei ssp. paracasei strain F19 (LF19) to healthy term infants from 4 to 13 months of age could maintain some of the beneficial effects conferred by breastfeeding on gut microbial composition, with possible effects on gut microbial function, T cell function, Th1/Th2 immune balance and eczema incidence.Study design: Infants were randomized to daily intake of cereals with (n=89) or without LF19 (n=90) from 4-13 months of age. Clinical outcome measures were monitored by diaries and a questionnaire. Stool and blood samples were obtained at 4, 6½, 9, 13 and 5½, 6½, 12 and 13 months of age, respectively. Stool samples were analyzed for lactobacilli counts by conventional culture methods and the presence of LF19 was verified by randomly amplified polymerase chain reaction (RAPD-PCR). Fecal short-chain fatty acid (SCFA) pattern, a proxy for gut microbial function, was determined by gas-liquid chromatography. After polyclonal or specific activation of T cells, the cytokine mRNA expression levels [interleukin 2 (IL2), IFN-, IL4 and IL10] were determined on isolated mRNA by quantitative real time reverse transcriptase-PCR. Serum concentrations of total and specific IgE antibodies, Haemophilus influenzae type b, diphtheria and tetanus toxoid specific IgG antibodies were analyzed by enzyme immunoassay.Results: Feeding LF19 maintained high fecal lactobacilli counts during weaning. Persistent colonization with LF19 induced differences in the fecal SCFA pattern. The cumulative incidence of eczema was lower in the probiotic group, in conjunction with a higher IFN-γ/IL4 mRNA ratio in polyclonally activated T cells. Even though there was an effect by LF19 on Th1/Th2 immune balance, there was no effect on IgE sensitization. Infants in both groups increased their capacity to express both Th1 and Th2 cytokines during the second half of infancy but the expression was still lower than that of adults. Infants in the probiotic group had lower IL2 levels after polyclonal T cell activation at 13 months of age compared with infants in the placebo group. Infants fed LF19 did not have fewer infections, but had fewer days with antibiotic prescription compared with infants fed placebo. In addition, compared to placebo, persistent colonization by LF19 enhanced specific vaccine responses to protein antigens during the course of vaccination.Conclusions: We conclude that feeding LF19 was safe, based on no observed adverse effects in our study. Infants in both groups demonstrated maturation of adaptive immune responses during weaning. Adding probiotics in complementary foods during weaning reduced the risk of eczema by 50%, with a concomitant shift towards an enhanced Th1/Th2 ratio. The reduction of eczema might be explained by probiotic effects on both T cell-mediated immune responses and reinforced gut microbial function.
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