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Concept: Probiotics


There are few carefully-designed studies investigating the safety of individual probiotics approved under Investigational New Drug policies.

Concepts: Gut flora, Microbiology, Probiotic, Lactobacillus, Lactobacillaceae, Lactobacillus reuteri, Probiotics


Recent studies suggested that manipulation of the composition of the microbial ecosystem in the gut might be a novel approach in the treatment of obesity. Such treatment might consist of altering the composition of the microbial communities of an obese individual by administration of beneficial microorganisms, commonly known as probiotics. Here, we intend to contribute to the developmental process of probiotic treatment of human obesity. The aim is to review the evidence regarding the potential effect of probiotic strains on reduction of weight and body fat. A literature study was conducted focusing on clinical trials that examined the effect of specific microorganisms on body weight control. Analysis of the eligible articles pointed out that Lactobacillus gasseri SBT 2055, Lactobacillus rhamnosus ATCC 53103, and the combination of L. rhamnosus ATCC 53102 and Bifidobacterium lactis Bb12 may reduce adiposity, body weight, and weight gain. This suggests that these microbial strains can be applied in the treatment of obesity. Furthermore, short chain fatty acid production and low grade inflammation were found as the underlying mechanisms of action that influence metabolism and affect body weight. These findings might contribute to the development of probiotic treatment of obesity. Further research should be directed to the most effective combination and dosage rate of probiotic microorganisms.

Concepts: Gut flora, Nutrition, Microbiology, Obesity, Probiotic, Lactobacillus, Lactobacillus rhamnosus, Probiotics


Two experiments examined probiotic pretreatment (Lactobacillus rhamnosus GG) on obsessive-compulsive disorder (OCD)-like behavior induction by RU 24969 in BALB/cJ house mice. In the first experiment, two groups were defined by their daily pretreatment by oral gavage of either (a) L. rhamnosus (1×10 CFU/day) or (b) the saline vehicle. Both a 2- and 4-week probiotic pretreatment attenuated OCD-like behavior induction (increased perseverative open-field locomotion, stereotypic turning, and marble burying) relative to saline pretreatment. Experiment 2 re-examined the 2-week probiotic pretreatment while also comparing it to a 4-week fluoxetine pretreatment. Again, groups were defined by daily pretreatment of either (a) L. rhamnosus for 2 weeks, (b) the saline vehicle for 2 weeks, or © fluoxetine (10 mg/kg) for 4 weeks. Pretreatment by either L. rhamnosus or fluoxetine blocked the induction of OCD-like behavior compared with saline pretreatment. Thus the 2-week probiotic pretreatment was again effective. Although side effects of fluoxetine or L. rhamnosus on androgen-dependent behaviors could not be demonstrated, L. rhamnosus treatment appeared comparable to fluoxetine treatment in attenuating mouse OCD-like behaviors.

Concepts: Microbiology, Probiotic, Lactobacillus, Mouse, Lactobacillus rhamnosus, Lactobacillaceae, Probiotics


Enniatins (ENs) are secondary metabolites produced by several Fusarium strains, chemically characterized as N-methylated cyclohexadepsipeptides. These compounds are known to act as antifungal and antibacterial agents, but they also possess anti-insect and phytotoxic properties. In this study, the antimicrobial effect of pure fractions of the bioactive compounds ENs A, A1, A2, B, B1, and B4 was tested towards nine probiotic microrganisms, twenty-two Saccharomyces cerevisiae strains and nine Bacillus subtilis strains. Antimicrobial analyses were carried out the disc-diffusion method using ENs concentrations ranging from 0.2 to 20,000 ng. Plates were incubated for 24h at 37°C before reading the diameter of the inhibition spots. ENs A, A1, A2, B, B1 and B4, were active against several microorganisms with inhibition halos ranging from 3 to 12 mm in diameter. The most active mycotoxin was the EN A1, which reduced the microbial growth of 8 strains at the dose of 20,000 ng, with inhibition spots sized between 8 and 12 mm. ENs B and B4 showed no antimicrobial activity towards the microorganisms tested at doses up to 20,000 ng per disc.

Concepts: Bacteria, Microbiology, Fungus, Saccharomyces cerevisiae, Brewing, Bacillus, Bacillus subtilis, Probiotics


The beneficial effects of probiotics are now widely reported, although there are only a few studies on their anti-aging effects. We have found that Lactobacillus plantarum HY7714 (HY7714) improves skin hydration and has anti-photoaging effects, and in the present study, we have further evaluated the anti-aging effect of HY7714 via a randomized, double blind, placebo-controlled clinical trial. The trial included 110 volunteers aged 41 and 59 years who have dry skin and wrinkles. Participants took 1 × 10(10) CFU/day of HY7714 (probiotic group) or a placebo (placebo group) for 12 weeks. Skin hydration, wrinkles, skin gloss, and skin elasticity were measured every 4 weeks during the study period. There were significant increases in the skin water content in the face (p<0.01) and hands (p<0.05) at week 12 in the probiotic group. Transepidermal water loss decreased significantly in both groups at weeks 4, 8, and 12 (p<0.001 compared to baseline), and was suppressed to a greater extent in the face and forearm in the probiotic group at week 12. Volunteers in the probiotic group had a significant reduction in wrinkle depth at week 12, and skin gloss was also significantly improved by week 12. Finally, skin elasticity in the probiotic group improved by 13.17% (p<0.05 vs. controls) after 4 weeks and by 21.73% (p<0.01 vs. controls) after 12 weeks. These findings are the preliminary confirmation of the anti-aging benefit to the skin of L. plantarum HY7714 as a nutricosmetic agent.

Concepts: Clinical trial, Microbiology, Effectiveness, Skin, Placebo, Lactobacillus, Lactobacillus plantarum, Probiotics


Celiac disease is characterized by enhanced intestinal paracellular permeability due to alterations of function and expression of tight junction (TJ) proteins including ZO-1, Claudin-1 and Occludin. Polyamines are pivotal in the control of intestinal barrier function and are also involved in the regulation of intercellular junction proteins. Different probiotic strains may inhibit gliadin-induced toxic effects and the Lactobacillus rhamnosus GG (L.GG) is effective in the prevention and treatment of gastrointestinal diseases. Aims of the study were to establish in epithelial Caco-2 cells whether i) gliadin affects paracellular permeability and polyamine profile; ii) co-administration of viable L.GG, heat-killed L.GG (L.GG-HK) or its conditioned medium (L.GG-CM) preserves the intestinal epithelial barrier integrity. Additionally, the effects of L.GG on TJ protein expression were tested in presence or absence of polyamines.

Concepts: DNA, Microbiology, Digestive system, Probiotic, Lactobacillus, Lactobacillus rhamnosus, Lactobacillaceae, Probiotics


IMPORTANCE Excessive infant crying is common, distressing, but without proven effective prevention or management options. Probiotics may be a promising solution. OBJECTIVE To examine whether probiotics are effective in the prevention/management of crying (“colic”) in infants 3 months or younger. DATA SOURCES A systematic search of MEDLINE, EMBASE, and the Cochrane Library, supplemented by the metaRegister of Controlled Trials. STUDY SELECTION Studies that randomized infants 3 months or younger to oral probiotics vs placebo or no or standard treatment with the outcome of infant crying, measured as the duration or number of episodes of infant crying/distress or diagnosis of “infant colic.” Twelve of the 1180 initially identified studies were selected. DATA EXTRACTION AND SYNTHESIS This review/meta-analysis was conducted according to guidelines from the Cochrane Handbook for Systematic Reviews of Interventions, with reporting following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Data were independently extracted by 3 of us. MAIN OUTCOME(S) AND MEASURE(S) Infant crying, measured as the duration or number of episodes of infant crying/distress, or diagnosis of “infant colic.” RESULTS Of the 12 trials (1825 infants) reviewed, 6 suggested probiotics reduced crying, and 6 did not. Three of the 5 management trials concluded probiotics effectively treat colic in breastfed babies; 1 suggested possible effectiveness in formula-fed babies with colic, and 1 suggested ineffectiveness in breastfed babies with colic. Meta-analysis of 3 small trials of breastfed infants with colic found that Lactobacillus reuteri markedly reduced crying time at 21 days (median difference, -65 minutes/d; 95% CI, -86 to -44). However, all trials had potential biases. Meanwhile, of 7 prevention trials, 2 suggested possible benefits. Considerable variability in the study populations, study type, delivery mode/dose of probiotic supplementation, and outcomes precluded meta-analysis. CONCLUSIONS AND RELEVANCE Although L reuteri may be effective as treatment for crying in exclusively breastfed infants with colic, there is still insufficient evidence to support probiotic use to manage colic, especially in formula-fed infants, or to prevent infant crying. Results from larger rigorously designed studies applicable to all crying infants will help draw more definitive conclusions.

Concepts: Infant, Evidence-based medicine, Systematic review, Probiotic, Lactobacillus, Lactobacillus reuteri, Probiotics, Baby colic


We previously demonstrated that short-term oral administration of the probiotic Lactobacillus reuteri 6475 enhanced bone density in male but not female mice. We also established that L. reuteri 6475 enhanced bone health and prevented bone loss in estrogen-deficient female mice. In this study, we tested whether a mild inflammatory state and/or a long-term treatment with the probiotic was required to promote a positive bone effect in estrogen-sufficient female mice.

Concepts: Gut flora, Female, Microbiology, Probiotic, Lactobacillus, Lactobacillaceae, Lactobacillus reuteri, Probiotics


A limited number of studies have investigated the potential of probiotics to promote wound healing in the digestive tract. The aim of the current investigation was to determine whether probiotic bacteria or their extracts could be beneficial in cutaneous wound healing. A keratinocyte monolayer scratch assay was used to assess re-epithelialization; which comprises keratinocyte proliferation and migration. Primary human keratinocyte monolayers were scratched then exposed to lysates of Lactobacillus (L) rhamnosus GG, L. reuteri, L. plantarum or L. fermentum. Re-epithelialization of treated monolayers was compared to that of untreated controls. Lysates of L. rhamnosus GG and L. reuteri significantly increased the rate of re-epithelialization, with L. rhamnosus GG being the most efficacious. L. reuteri increased keratinocyte proliferation while L. rhamnosus GG lysate significantly increased proliferation and migration. Microarray analysis of L. rhamnosus GG treated scratches showed increased expression of multiple genes including the chemokine CXCL2 and its receptor CXCR2. These are involved in normal wound healing where they stimulate keratinocyte proliferation and/or migration. Increased protein expression of both CXCL2 and CXCR2 were confirmed by ELISA and immunoblotting. These data demonstrate that L. rhamnosus GG lysate accelerates re-epithelialization of keratinocyte scratch assays, potentially via chemokine receptor pairs that induce keratinocyte migration.

Concepts: Microbiology, Digestive system, Probiotic, Lactobacillus, Lactobacillus rhamnosus, Lactobacillaceae, Bacteriology, Probiotics


Objective The aim of this study was to determine effects of probiotic yogurt and multispecies probiotic capsule supplementation on mental health and hypothalamic-pituitary-adrenal axis in petrochemical workers. Methods The present randomized double-blind, placebo-controlled trial was conducted on 70 petrochemical workers. Subjects were randomly divided into three groups to receive 100 g/day probiotic yogurt + one placebo capsule (n = 25) or one probiotic capsule daily + 100 g/day conventional yogurt (n = 25) or 100 g/day conventional yogurt + one placebo capsule (n = 20) for 6 weeks. Mental health parameters including general health questionnaire (GHQ) and depression anxiety and stress scale (DASS) scores were measured. Fasting blood samples were obtained at the beginning and 6 weeks after the intervention to quantify hypothalamic-pituitary-adrenal axis. Results After 6 weeks of intervention, a significant improvement of GHQ was observed in the probiotic yogurt (18.0 ± 1.5 vs. 13.5 ± 1.9, P = 0.007) and in the probiotic capsule group (16.9 ± 1.8 vs. 9.8 ± 1.9, P = 0.001), as well as a significant improvement in DASS scores in the probiotic yogurt (23.3 ± 3.7 vs. 13.0 ± 3.7, P = 0.02) and the probiotic capsule group (18.9 ± 3.2 vs. 9.4 ± 4.0, P = 0.006). However, there was no significant improvement in the conventional yogurt group (P = 0.05 for GHQ and P = 0.08 for DASS). Discussion The consumption of probiotic yogurt or a multispecies probiotic capsule had beneficial effects on mental health parameters in petrochemical workers.

Concepts: Anxiety, Placebo, Randomness, Probiotic, Lactobacillus, Diarrhea, Probiotics