Probiotics Research

2015 Meta-Analyses on Probiotics

A systematic review and meta-analysis of probiotics for the treatment of allergic rhinitis.

Int Forum Allergy Rhinol. 2015 Jun;5(6):524-32. doi: 10.1002/alr.21492. Epub 2015 Apr 20.

Abstract

BACKGROUND:

Probiotics have proven beneficial in a number of immune-mediated and allergic diseases. Several human studies have evaluated the efficacy of probiotics in allergic rhinitis; however, evidence for their use has yet to be firmly established. The current systematic review seeks to synthesize the results of available randomized trials.

METHODS:

In a systematic review and meta-analysis, the Medline, EMBASE, and Cochrane Library databases were reviewed and randomized controlled trials (RCTs) were extracted based on defined inclusion criteria. The effect of probiotics on Rhinitis Quality of Life (RQLQ) scores, Rhinitis Total Symptom Scores (RTSS), as well as total and antigen-specific serum immunoglobulin E (IgE) levels were evaluated by meta-analysis.

RESULTS:

A total of 23 studies with 1919 patients were identified, including 21 double-blind RCTs and 2 randomized crossover studies. Multiple probiotic strains, study populations, and outcome measures were used in individual trials. Seventeen studies showed a significant clinical benefit from the use of probiotics in at least 1 outcome measure when compared to placebo, whereas 6 trials showed no benefit. Among the trials eligible for meta-analysis, the use of probiotics resulted in a significant improvement in RQLQ scores compared to placebo (standard mean difference [SMD] -2.23; p = 0.02). Probiotics had no effect on RTSS (SMD -0.36; p = 0.13) or total IgE levels (SMD 0.01; p = 0.94), although there was a trend toward a reduction in antigen-specific IgE (SMD 0.20; p = 0.06) in the placebo group compared to probiotic.

CONCLUSION:

Probiotics may be beneficial in improving symptoms and quality of life in patients with allergic rhinitis; however, current evidence remains limited due to study heterogeneity and variable outcome measures. Additional high-quality studies are needed to establish appropriate recommendations.

2015 Research Studies involving Lactobacillus acidophilus

Lactobacillus acidophilus counteracts enteropathogenic E. coli-induced inhibition of butyrate uptake in intestinal epithelial cells.

Am J Physiol Gastrointest Liver Physiol. 2015 Oct 1;309(7):G602-7. doi: 10.1152/ajpgi.00186.2015. Epub 2015 Aug 13.

Butyrate, a key short-chain fatty acid metabolite of colonic luminal bacterial action on dietary fiber, serves as a primary fuel for the colonocytes, ameliorates mucosal inflammation, and stimulates NaCl absorption. Absorption of butyrate into the colonocytes is essential for these intracellular effects.

Monocarboxylate transporter 1 (MCT1) plays a major role in colonic luminal butyrate absorption.

Previous studies (Tan J, McKenzie C, Potamitis M, Thorburn AN, Mackay CR, Macia L. Adv Immunol 121: 91-119, 2014.) showed decreased MCT1 expression and function in intestinal inflammation.

We have previously shown (Borthakur A, Gill RK, Hodges K, Ramaswamy K, Hecht G, Dudeja PK. Am J Physiol Gastrointest Liver Physiol 290: G30-G35, 2006.) impaired butyrate absorption in human intestinal epithelial Caco-2 cells due to decreased MCT1 level at the apical cell surface following enteropathogenic E. coli (EPEC) infection.

Current studies, therefore, examined the potential role of probiotic Lactobacilli in stimulating MCT1-mediated butyrate uptake and counteracting EPEC inhibition of MCT1 function.

Of the five species of Lactobacilli, short-term (3 h) treatment with L. acidophilus (LA) significantly increased MCT1-mediated butyrate uptake in Caco-2 cells. Heat-killed LA was ineffective, whereas the conditioned culture supernatant of LA (LA-CS) was equally effective in stimulating MCT1 function, indicating that the effects are mediated by LA-secreted soluble factor(s).

Furthermore, LA-CS increased apical membrane levels of MCT1 protein via decreasing its basal endocytosis, suggesting that LA-CS stimulation of butyrate uptake could be secondary to increased levels of MCT1 on the apical cell surface. LA-CS also attenuated EPEC inhibition of butyrate uptake and EPEC-mediated endocytosis of MCT1.

Our studies highlight distinct role of specific LA-secreted molecules in modulating colonic butyrate absorption.

Lactobacilli vaginal colonisation after oral consumption of Respecta(®) complex: a randomised controlled pilot study.

Arch Gynecol Obstet. 2015 Oct;292(4):861-7. doi: 10.1007/s00404-015-3711-4. Epub 2015 Apr 9.

The aim of the current pilot study was to determine if oral consumption of a combination of two probiotics; L. acidophilus La-14, L. rhamnosus HN001, and bovine lactoferrin (Respecta(®) complex), would lead to the detection with molecular techniques of the consumed probiotic strains in the vagina.

METHODS:

Healthy volunteers (40) consumed the study product twice daily for 2 weeks. Vaginal swabs were collected at 0, 1, 2 and 3 weeks and analysed for the consumed organisms by qPCR.

RESULTS:

Vaginal L. rhamnosus and L. acidophilus levels were significantly increased on days 14 and 21. On days 14 and 21 a significant number of women had increased levels of vaginal L. acidophilus and on days 7 and 21 a significant number of women had increased levels of vaginal L. rhamnosus.

CONCLUSIONS:

Consumption of L. acidophilus La-14, L. rhamnosus HN001 in combination with bovine lactoferrin leads to vaginal detection; even 1 week after consumption was stopped. This provides a basis for future studies on urogenital tract health.

2015 Research Studies involving Lactobacillus plantarum

Does Lactobacillus plantarum or ultrafiltration process improve Ca, Mg, Zn and P bioavailability from fermented goats’ milk?

Food Chem. 2015 Nov 15;187:314-21. doi: 10.1016/j.foodchem.2015.04.051. Epub 2015 Apr 21.

Ca, Mg, Zn and P bioavailability from two experimental ultrafiltered fermented goats’ milks (one of them with the probiotic Lactobacillus plantarum and another one without it), and fermented goats’ milk samples available in the market were evaluated.

Solubility, dialysability and a model combining simulated gastrointestinal digestion and mineral retention, transport and uptake by Caco-2 cells were used to assess bioavailability.

The highest Ca, Mg, Zn and P bioavailability values always corresponded to the fermented milk developed by our research group, which could be explained by the effect of milk ultrafiltration.

The fermented milk with L. plantarum showed higher Ca retention than the ones without the microorganism, and major Ca uptake when compared to commercial products.

This fact could be attributed to a positive effect exerted by the probiotic strain.

Probiotic strain Lactobacillus plantarum 299v increases iron absorption from an iron-supplemented fruit drink: a double-isotope cross-over single-blind study in women of reproductive age.

Br J Nutr. 2015 Oct 28;114(8):1195-202. doi: 10.1017/S000711451500241X.

Iron deficiency is common, especially among young women. Adding probiotics to foods could be one way to increase iron absorption.

The aim of this study was to test the hypothesis that non-haem iron absorption from a fruit drink is improved by adding Lactobacillus plantarum 299v (Lp299v).

Iron absorption was studied in healthy women of reproductive age using a single-blind cross-over design in two trials applying the double-isotope (55Fe and 59Fe) technique.

  • In Trial 1, iron absorption from a fruit drink containing 109 colony-forming units (CFU) Lp299v was compared with that from a control drink without Lp299v.
  • Trial 2 had the same design but 1010 CFU were used.
  • The test and control drinks contained approximately 5 mg of iron as ferrous lactate and were labelled with 59Fe (B) and 55Fe (A), respectively, and consumed on 4 consecutive days in the order AABB.
  • Retention of the isotopes was measured with whole-body counting and in blood.
  • Mean iron absorption from the drink containing 109 CFU Lp299v (28·6(sd 12·5) %) was significantly higher than from the control drink (18·5(sd 5·8) %), n 10, P<0·028).
  • The fruit drink with 1010 CFU Lp299v gave a mean iron absorption of 29·1(sd 17·0) %, whereas the control drink gave an absorption of (20·1(sd 6·4) %) (n 11, P<0·080).
  • The difference in iron absorption between the 109 CFU Lp299v and the 1010 CFU Lp299v drinks was not significant (P=0·941).

In conclusion, intake of probiotics can increase iron absorption by approximately 50% from a fruit drink having an already relatively high iron bioavailability.

2015 Research Studies involving Lactobacillus rhamnosus

Lactobacilli vaginal colonisation after oral consumption of Respecta(®) complex: a randomised controlled pilot study.

Arch Gynecol Obstet. 2015 Oct;292(4):861-7. doi: 10.1007/s00404-015-3711-4. Epub 2015 Apr 9.

The aim of the current pilot study was to determine if oral consumption of a combination of two probiotics; L. acidophilus La-14, L. rhamnosus HN001, and bovine lactoferrin (Respecta(®) complex), would lead to the detection with molecular techniques of the consumed probiotic strains in the vagina.

METHODS:

Healthy volunteers (40) consumed the study product twice daily for 2 weeks. Vaginal swabs were collected at 0, 1, 2 and 3 weeks and analysed for the consumed organisms by qPCR.

RESULTS:

Vaginal L. rhamnosus and L. acidophilus levels were significantly increased on days 14 and 21. On days 14 and 21 a significant number of women had increased levels of vaginal L. acidophilus and on days 7 and 21 a significant number of women had increased levels of vaginal L. rhamnosus.

CONCLUSIONS:

Consumption of L. acidophilus La-14, L. rhamnosus HN001 in combination with bovine lactoferrin leads to vaginal detection; even 1 week after consumption was stopped. This provides a basis for future studies on urogenital tract health.