Lactobacillus Research Today is a free monthly online journal that collates and summarizes the latest research about Lactobacillus, including details on probiotics, digestion, diet, health, lactobacillus acidophilus.

Conjugated linoleic acids produced by Lactobacillus dissociates IKK-gamma and Hsp90 complex in Helicobacter pylori-infected gastric epithelial cells.

Kim JM, Kim JS, Kim YJ, Oh YK, Kim IY, Chee YJ, Han JS, Jung HC

Department of Microbiology, Hanyang University College of Medicine, Seoul, South Korea. jungmogg@hanyang.ac.kr

Although probiotics have been reported to reduce the gastric inflammatory response to Helicobacter pylori infection, little information is available regarding the molecular mechanisms behind this reduction. This study investigates the role of conjugated linoleic acids (CLA) produced by probiotics in interactions of IkappaB kinase (IKK) and heat shock protein 90 (Hsp90) to activate the nuclear factor-kappaB (NF-kappaB) signaling pathway in human gastric epithelial cells infected with H. pylori. Conditioned medium (CM) containing Lactobacillus acidophilus-producing CLA significantly inhibited the activated NF-kappaB signals and the upregulated expression of interleukin-8 (IL-8) in MKN-45 cells infected with H. pylori. Pretreatment with CM with CLA attenuated the increased IKK activity induced by H. pylori. Transfection of siRNA for IKK-beta dramatically reduced H. pylori-induced IkappaBalpha phosphorylation, but siRNA for IKK-alpha had little effect on IkappaBalpha phosphorylation, although the siRNA for IKK-alpha significantly decreased IL-8 production. Furthermore, Hsp90 was associated with IKK-alpha and IKK-gamma in H. pylori-infected cells, and CM with CLA dissociated the complex between Hsp90 and IKK-gamma. These results suggest that CLA produced by probiotics has anti-inflammatory activity in gastric epithelial cells infected with H. pylori via dissociation of the IKK-gamma and Hsp90 complex.

Published 24 April 2008 in Lab Invest, 88(5): 541-52.
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Articles on Lactobacillus published 16 April 2008:

Mucosal delivery of therapeutic and prophylactic molecules using lactic acid bacteria.   Nat Rev Microbiol, 6(5): 349-62.

Studies of lactic acid bacteria (LAB) as delivery vehicles have focused mainly on the development of mucosal vaccines, with much effort being devoted to the generation of genetic tools for antigen expression in different bacterial locations. Subsequently, interleukins have been co-expressed with antigens in LAB to enhance the immune response that is raised against the antigen. LAB have also been used as a delivery system for a range of molecules that have different applications, including ... [Abstract] [Full-text]

Articles on Lactobacillus published 2 April 2008:

Randomized, double-blind, placebo-controlled trial of probiotics for primary prevention: no clinical effects of Lactobacillus GG supplementation.   Pediatrics, 121(4): e850-6.

BACKGROUND: The value of probiotics for primary prevention is controversial. Published trials vary considerably in study design and the applied probiotics, thereby limiting comparability of the results. OBJECTIVE: The purpose of this trial was to study the preventive effect of the probiotic Lactobacillus GG on the development of atopic dermatitis. METHODS: In a double-blind, placebo-controlled prospective trial, 105 pregnant women from families with > or = 1 member (mother, father, or child) ... [Abstract] [Full-text]

Articles on Lactobacillus published 21 March 2008:

Lactobacillus sakei/curvatus is the prevailing lactic acid bacterium group in spoiled maatjes herring.   Food Microbiol, 25(3): 529-33.

A total of 164 lactic acid bacteria (LAB) isolated from spoiled maatjes herring stored in air and under modified atmosphere at 4 or 10 degrees C were characterised and identified using an rRNA gene restriction pattern (ribotype) database. The isolates were initially grouped according to their HindIII restriction endonuclease profiles and further identified to species level using numerical analysis. Lactobacillus sakei, Lactobacillus curvatus and strains of the L. curvatus spp./Lactobacillus ... [Abstract] [Full-text]

Microbiological study of lactic acid bacteria in kefir grains by culture-dependent and culture-independent methods.   Food Microbiol, 25(3): 492-501.

Lactic acid bacteria (LAB) in different original kefir grains were first assessed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) by a culture-dependent way, and were further confirmed by DNA sequencing techniques. Results indicated that a combined method of cultivation with PCR-DGGE and subsequent DNA sequencing could successfully identify four LAB strains from three kefir grains from Taiwan (named Hsinchu, Mongolia and Ilan). Lactobacillus kefiri accounted, ... [Abstract] [Full-text]

Whey fermentation by thermophilic lactic acid bacteria: evolution of carbohydrates and protein content.   Food Microbiol, 25(3): 442-51.

Whey, a by-product of the cheese industry usually disposed as waste, is a source of biological and functional valuable proteins. The aim of this work was to evaluate the potentiality of three lactic acid bacteria strains to design a starter culture for developing functional whey-based drinks. Fermentations were performed at 37 and 42 degrees C for 24h in reconstituted whey powder (RW). Carbohydrates, organic acids and amino acids concentrations during fermentation were evaluated by RP-HPLC. ... [Abstract] [Full-text]

Protection mechanisms of sugars during different stages of preparation process of dried lactic acid starter cultures.   Food Microbiol, 25(3): 429-41.

Sugars are recognized protectants used in the preparation of dried starter cultures for fermented food industries, particularly as additives for the drying media. They increase viability of the starter cultures during drying and storage. This review intends to summarize and discuss their roles in each step of the preparation process. The main topics cover the role of sugars in the induction of compatible solutes and alteration of fermentation metabolites during growing of cells, the reduction ... [Abstract] [Full-text]

Articles on Lactobacillus published 19 March 2008:

Strain-specific inhibition of Helicobacter pylori by Lactobacillus salivarius and other lactobacilli.   J Antimicrob Chemother, 61(4): 831-4.

OBJECTIVES: To investigate the anti-Helicobacter pylori activity of 28 strains of Lactobacillus salivarius and 12 other lactobacilli, isolated from different sites and from different geographical regions. METHODS: An in vitro agar plate diffusion assay was employed to assess the Lactobacillus anti-H. pylori activity. RESULTS: Nine out of 28 L. salivarius strains and 3/12 other Lactobacillus species tested inhibited H. pylori growth. There was no correlation between ecological niche/geographical ... [Abstract] [Full-text]

Selective pressure affects transfer and establishment of a Lactobacillus plantarum resistance plasmid in the gastrointestinal environment.   J Antimicrob Chemother, 61(4): 845-52.

OBJECTIVES AND METHODS: A Lactobacillus plantarum strain recently isolated from French raw-milk cheese was tested for its ability to transfer a small plasmid pLFE1 harbouring the erythromycin resistance gene erm(B) to Enterococcus faecalis. Mating was studied in vitro and in different gastrointestinal environments using gnotobiotic rats as a simple in vivo model and streptomycin-treated mice as a more complex model. Transfer and establishment of transconjugants in the intestine were ... [Abstract] [Full-text]

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