Katja Hatakka

Effect of long term consumption of probiotic milk on infections in children attending day care centres: double blind, randomised trial

Abstract Objective: To examine whether long term consumption of a probiotic milk could reduce gastrointestinal and respiratory infections in children in day care centres. Design: Randomised, double blind, placebo controlled study over seven months. Setting: 18 day care centres in Helsinki, Finland. Participants: 571 healthy children aged 1-6 years: 282 (mean (SD) age 4.6 (1.5) years) in the intervention group and 289 (mean (SD) age 4.4 (1.5) years) in the control group. Intervention: Milk with or without Lactobacillus GG. Average daily consumption of milk in both groups was 260 ml. Main outcome measures: Number of days with respiratory and gastrointestinal symptoms, absences from day care because of illness, respiratory tract infections diagnosed by a doctor, and course of antibiotics. Results: Children in the Lactobacillus group had fewer days of absence from day care because of illness (4.9 (95% confidence interval 4.4 to 5.5) v 5.8 (5.3 to 6.4) days, 16% difference, P=0.03; age adjusted 5.1 (4.6 to 5.6) v 5.7 (5.2 to 6.3) days, 11% difference, P=0.09). There was also a relative reduction of 17% in the number of children suffering from respiratory infections with complications and lower respiratory tract infections (unadjusted absolute % reduction −8.6 (−17.2 to −0.1), P=0.05; age adjusted odds ratio 0.75 (0.52 to 1.09), P=0.13) and a 19% relative reduction in antibiotic treatments for respiratory infection (unadjusted absolute % reduction −9.6 (−18.2 to −1.0), P=0.03; adjusted odds ratio 0.72 (0.50 to 1.03), P=0.08) in the Lactobacillus group. Conclusions: Lactobacillus GG may reduce respiratory infections and their severity among children in day care. The effects of the probiotic Lactobacillus GG were modest but consistently in the same direction. What is already known on this topic Children attending day care centres are at high risk of respiratory and gastrointestinal infection The successful prevention of respiratory infections could be extremely useful for families and for society in general Short term use of probiotic bacteria has been shown to reduce the severity of rotavirus diarrhoea and the incidence of diarrhoea associated with the use of antibiotics What this study adds In a double blind, randomised, long term study milk containing Lactobacillus GG slightly reduced the incidence of respiratory infections and antibiotic treatment in children

Comparative genomic analysis of Lactobacillus rhamnosus GG reveals pili containing a human- mucus binding protein

To unravel the biological function of the widely used probiotic bacterium Lactobacillus rhamnosus GG, we compared its 3.0-Mbp genome sequence with the similarly sized genome of L. rhamnosus LC705, an adjunct starter culture exhibiting reduced binding to mucus. Both genomes demonstrated high sequence identity and synteny. However, for both strains, genomic islands, 5 in GG and 4 in LC705, punctuated the colinearity. A significant number of strain-specific genes were predicted in these islands (80 in GG and 72 in LC705). The GG-specific islands included genes coding for bacteriophage components, sugar metabolism and transport, and exopolysaccharide biosynthesis. One island only found in L. rhamnosus GG contained genes for 3 secreted LPXTG-like pilins (spaCBA) and a pilin-dedicated sortase. Using anti-SpaC antibodies, the physical presence of cell wall-bound pili was confirmed by immunoblotting. Immunogold electron microscopy showed that the SpaC pilin is located at the pilus tip but also sporadically throughout the structure. Moreover, the adherence of strain GG to human intestinal mucus was blocked by SpaC antiserum and abolished in a mutant carrying an inactivated spaC gene. Similarly, binding to mucus was demonstrated for the purified SpaC protein. We conclude that the presence of SpaC is essential for the mucus interaction of L. rhamnosus GG and likely explains its ability to persist in the human intestinal tract longer than LC705 during an intervention trial. The presence of mucus-binding pili on the surface of a nonpathogenic Gram-positive bacterial strain reveals a previously undescribed mechanism for the interaction of selected probiotic lactobacilli with host tissues.

Effect of Long–Term Consumption of a Probiotic Bacterium, Lactobacillus rhamnosus GG, in Milk on Dental Caries and Caries Risk in Children

Lactobacillus rhamnosus GG, ATCC (LGG), has shown antagonism to many bacteria including mutans streptococci. This randomized, double–blind, placebo–controlled intervention study was designed to examine whether milk containing LGG has an effect on caries and the risk of caries in children when compared with normal milk. 594 children, 1–6 years old, from 18 municipal day–care centres were included. The children received the milk with meals from coded containers 5 days a week in the day–care centres for 7 months. The children’s oral health was recorded at baseline and at the end, using WHO criteria. The caries risk was calculated based on clinical and microbiological data, comprising mutans streptococcus levels from dental plaque and saliva. The risk was classified as high if the child had a dmft/DMFT or initial caries score >0, and a mutans streptococcus count ≧105 CFU/ml. The results showed less dental caries in the LGG group and lower mutans streptococcus counts at the end of the study. LGG was found to reduce the risk of caries significantly (OR = 0.56, p = 0.01; controlled for age and gender, OR = 0.51, p = 0.004). The effect was particularly clear in the 3– to 4–year–olds. Thus, milk containing the probiotic LGG bacteria may have beneficial effects on children’s dental health.

A probiotic mixture alleviates symptoms in irritable bowel syndrome patients: a controlled 6-month intervention

Background : Irritable bowel syndrome is a gastrointestinal disorder of unknown aetiology. The effect of probiotics in this syndrome remains unclear.

Probiotics Reduce the Prevalence of Oral Candida in the Elderly : a Randomized Controlled Trial

Overgrowth of oral yeast is a common problem among the elderly. Probiotic bacteria are known to inhibit the growth of pathogenic microbes. We tested the hypothesis that cheese containing probiotic bacteria can reduce the prevalence of oral Candida. During this 16-week, randomized, double-blind, placebo-controlled study, 276 elderly people consumed daily 50 g of either probiotic (n = 136) or control cheese (n = 140). The primary outcome measure was the prevalence of a high salivary yeast count (≥ 104 cfu/mL) analyzed by the Dentocult® method. The prevalence decreased in the probiotic group from 30% to 21% (32% reduction), and increased in the control group from 28% to 34%. Probiotic intervention reduced the risk of high yeast counts by 75% (OR = 0.25, 95%CI 0.10–0.65, p = 0.004), and the risk of hyposalivation by 56% (OR = 0.44, 95%CI 0.19–1.01, p = 0.05). Thus, probiotic bacteria can be effective in controlling oral Candida and hyposalivation in the elderly.

Effects of probiotic therapy on the activity and activation of mild rheumatoid arthritis-a pilot study

Objective: To study the effects of Lactobacillus rhamnosus GG (LGG) on rheumatoid arthritis (RA). Methods: Twenty‐one RA patients were randomised to receive 2 capsules of LGG or a placebo twice daily in double‐blind fashion for 12 months. Arthritis activity was evaluated by clinical examination, HAQ index, and laboratory tests (e.g. ESR, CRP, pro‐ and anti‐inflammatory cytokines). Results: There were no statistical differences in the clinical parameters, biochemical variables and HAQ index between the study groups over the intervention period. The mean number of tender and swollen joints decreased from 8.3 to 4.6 in the Lactobacillus group and from 5.5 to 4.8 in the placebo group (p=0.41). According to the global assessment the RA activity was reduced in 71% (LGG group) vs. 30% (controls) (p=0.15). Serum IL‐1β increased slightly in the LGG group (p=0.07), but no differences were seen in IL‐6, TNF‐α, MPO, IL‐10 or 1L‐12. Conclusions: Although there were no statistical significant differences in the activity of RA, more subjects in the LGG group reported subjective well being. More studies on the effects of probiotic bacteria in RA are needed.

Persistence of probiotic strains in the gastrointestinal tract when administered as capsules, yoghurt, or cheese

Most clinical studies of probiotics use freeze-dried, powdered bacteria or bacteria packed in capsules. However, probiotics are commercially available in various food matrices, which may affect their persistence in the gastrointestinal tract. The objective of the study was to compare oral and faecal recovery during and after administration of a combination of Lactobacillus rhamnosus GG and LC705, Propionibacterium freudenreichii subsp. shermanii JS, and Bifidobacterium animalis subsp. lactis Bb12 as capsules, yoghurt, or cheese. This randomized, parallel-group, open-label trial (n=36) included a 4-week run-in, 2-week intervention, and 3-week follow-up period. Participants consumed 10(10)cfu/day of probiotic combination and provided saliva and faecal samples before, during, and after the intervention. Strain-specific real-time PCR was used to quantify the strains. L. rhamnosus GG was the only probiotic strain regularly recovered in saliva samples. During the intervention period it was recovered in the saliva of 88% of the volunteers at least once. No difference was found between the yoghurt and cheese groups. At the end of the intervention, L. rhamnosus GG and LC705 counts were high in faecal samples of all product groups (8.08 and 8.67log(10) genome copies/g, respectively). There was no matrix effect on strain quantity in faeces or the recovery time after ceasing the intervention. For P. freudenreichii subsp. shermanii JS and B. animalis subsp. lactis Bb12, a matrix effect was found at the end of the intervention (P<0.01 and P<0.001, respectively) and in the recovery time during follow-up (P<0.05 for both). Yoghurt yielded the highest faecal quantity of JS and Bb12 strains (8.01 and 9.89log(10) genome copies/g, respectively). The results showed that the administration matrix did not influence the faecal quantity of lactobacilli, but affected faecal counts of propionibacteria and bifidobacteria that were lower when consumed in cheese. Thus, the consumption of probiotics in yoghurt matrix is highly suitable for studying potential health benefits and capsules provide a comparable means of administration when the viability of the strain in the capsule product is confirmed.

The influence of Lactobacillus rhamnosus LC705 together with Propionibacterium freudenreichii ssp. shermanii JS on potentially carcinogenic bacterial activity in human colon

The bacterial enzymes beta-glucosidase, beta-glucuronidase, and urease may contribute to the development of colon cancer by generating carcinogens. A reduction in the activity of these enzymes by certain lactic acid bacteria is considered to be beneficial. This study examined fecal beta-glucosidase, beta-glucuronidase, and urease activities during administration of Lactobacillus rhamnosus LC705 (LC705) together with Propionibacterium freudenreichii ssp shermanii JS (PJS). Thirty-eight healthy men participated in this randomized, double-blind, placebo-controlled, two-period crossover study with treatment periods of 4 weeks. Subjects consumed daily bacterial or placebo capsules. Bacterial capsules contained viable LC705 and PJS (2x10(10) CFU of each strain daily). The activities of beta-glucosidase, beta-glucuronidase and urease, recovery of LC705 and PJS, and counts of total lactobacilli and propionibacteria were determined from feces. The mean fecal counts of total lactobacilli and propionibacteria as well as strains LC705 and PJS were significantly increased during the administration of bacteria (3.5-, 13-, 80- and 11-fold, respectively). beta-glucosidase activity decreased by 10% (P=0.18) and urease activity by 13% (P=0.16) during bacterial supplementation versus placebo. The change in beta-glucosidase activity was negatively correlated with the change in propionibacteria counts (R=-0.350, P=0.039), being -2.68 versus 0.94 nmol/min/mg protein in subjects with increased and unchanged/decreased propionibacteria, respectively (P=0.003). To conclude, the administration of LC705 and PJS was followed by an increase in the fecal counts of lactobacilli and propionibacteria and a decrease in the activity of beta-glucosidase with increasing counts of propionibacteria.

Lactobacillus rhamnosus LC705 Together with Propionibacterium freudenreichii ssp shermanii JS Administered in Capsules Is Ineffective in Lowering Serum Lipids

Objective: The aim of this study was to examine the effect of the administration of Lactobacillus rhamnosus strain LC705 and Propionibacterium freudenreichii ssp shermanii strain JS in capsules on serum cholesterol and triglyceride levels in mildly or moderately hypercholesterolemic men. Methods: Thirty-eight basically healthy men, mean age 42 years (range 24–55), mean cholesterol 6.2 mmol/L (5.3–8.2 mmol/L), participated in this double-blind, randomised, placebo-controlled, two-period crossover study with 4-week treatment periods. The subjects consumed daily two probiotic capsules containing viable Lactobacillus rhamnosus LC705 and Propionibacterium freudenreichii ssp shermanii JS (2 × 1010 colony forming units of each strain daily) or two placebo capsules. Serum lipids were assessed before the intervention, at the end of both 4-week treatment periods, and 2 weeks after the second treatment period. Dietary and lifestyle habits were carefully monitored. Results: All the subjects completed the study, and the probiotic capsules were well tolerated. Dietary habits and the intake of energy and nutrients, such as saturated fatty acids and cholesterol, did not differ between the treatment groups. No changes in total cholesterol, HDL cholesterol, LDL cholesterol or triglyceride levels were observed during the consumption of the probiotics compared to placebo. Conclusions: The administration of Lactobacillus rhamnosus LC705 and Propionibacterium freudenreichii ssp shermanii JS did not affect serum lipids.

Milk containing probiotic Lactobacillus rhamnosus GG and respiratory illness in children: a randomized, double-blind, placebo-controlled trial

Background/Objectives:To determine whether long-term daily consumption of milk containing probiotic Lactobacillus rhamnosus GG (GG) decreases respiratory illness in children.Subjects/Methods:A randomized, double-blind, placebo-controlled trial was conducted with 523 children aged 2–6 years attending day care centers in Finland. Subjects received either normal milk or the same milk with GG on three daily meals for 28 weeks. Daily recording of childrens’ symptoms was done by parents. Primary outcome data from 501 subjects were available for analysis, and data from 128 subjects were analyzed as completed cases in terms of recovery of GG in fecal samples.Results:Number of days with at least one respiratory symptom in all subjects was 5.03/month (95% confidence interval (CI): 4.92–5.15) in the GG group and 5.17/month (95% CI: 5.05–5.29) in the placebo group incidence rate ratio (IRR) 0.97; 95% CI: 0.94–1.00; P=0.098). In the completed cases, the figures were 4.71 days/month (95% CI: 4.52–4.90) in the GG group and 5.67 days/month (95% CI: 5.40–5.94) in the placebo group (IRR 0.83; 95% CI: 0.78–0.88; P<0.001).Conclusions:Consumption of GG reduced the occurence of respiratory illness in children attending day care centers in the completed cases subgroup, but not in the total population. Thus, future clinical trials are warranted to clarify the association between fecal recovery of a probiotic and the symptom prevalence.