The Experts below are selected from a list of 12210 Experts worldwide ranked by ideXlab platform
Hani Elnezami - One of the best experts on this subject based on the ideXlab platform.
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immunomodulation of Lactobacillus rhamnosus gg lgg derived soluble factors on antigen presenting cells of healthy blood donors
2016Co-Authors: Fiona Long Yan Fong, Hani Elnezami, Pirkka V KirjavainenAbstract:Lactobacillus rhamnosus GG (LGG) cells have been shown to promote type-1 immune responsiveness; however knowledge of immunomodulation of soluble factors secreted by LGG is limited. This is the first study to investigate whether LGG soluble factors promote a comparable immune responsiveness as the bacterial cells. Both treatments − LGG conditioned medium with (CM + LGG) or without (CM) LGG cells, in this study increased expression of several toll-like receptors (TLRs) in all studied cell types and antigen presentation-associated receptor HLA-DR in macrophages and “intermediate” monocytes; but decreased that of activation markers on monocytes and macrophages and production of IL-10, IL-12 and TNFα in macrophages. In co-culture with mononuclear cells, CM increased Th1-type cytokine profile but not as pronounced as CM + LGG. This study suggests that LGG soluble factors exert similar immunomodulatory effects as the intact cells, but cells may be required for optimal type-1 immune responsiveness polarizing capacity of this probiotic strain.
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Lactobacillus rhamnosus strain gg modulates intestinal absorption fecal excretion and toxicity of aflatoxin b1 in rats
2006Co-Authors: Silvia W Gratz, Martin Taubel, Risto Juvonen, Matti Viluksela, Paul C Turner, Hannu Mykkanen, Hani ElnezamiAbstract:In this study, the modulation of aflatoxin B1 (AFB1) uptake in rats by administration of the probiotic Lactobacillus rhamnosus GG was demonstrated. Fecal AFB1 excretion in GG-treated rats was increased via bacterial AFB1 binding. Furthermore, AFB1-associated growth faltering and liver injury were alleviated with GG treatment.
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Lactobacillus rhamnosus strain gg modulates intestinal absorption fecal excretion and toxicity of aflatoxin b 1 in rats
2006Co-Authors: Silvia Gratz, Martin Taubel, Matti Viluksela, Paul C Turner, Hannu Mykkanen, Risto O Juvonen, Hani ElnezamiAbstract:In this study, the modulation of aflatoxin B1 (AFB1) uptake in rats by administration of the probiotic Lactobacillus rhamnosus GG was demonstrated. Fecal AFB1 excretion in GG-treated rats was increased via bacterial AFB1 binding. Furthermore, AFB1-associated growth faltering and liver injury were alleviated with GG treatment.
Dietrich Knorr - One of the best experts on this subject based on the ideXlab platform.
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comparison of inactivation pathways of thermal or high pressure inactivated Lactobacillus rhamnosus atcc 53103 by flow cytometry analysis
2009Co-Authors: Edwin Ananta, Dietrich KnorrAbstract:The effect of thermal and pressure treatments on Lactobacillus rhamnosus ATCC 53103 was evaluated by flow cytometric analysis in conjunction to standard cultivation techniques. A double staining technique with fluorochromes carboxyfluorescein diacetate (cFDA) and propidium iodide (PI) revealed that depending on temperature regime used heat-killed cells had different fluorescence behaviors. Cells killed at 60 °C were not stained at all whereas heat treatment at 75 °C resulted in a single population entirely labelled by PI. These findings indicated that thermal-induced cell death was achievable with or without membrane degradation. Hydrostatic pressures beyond 400 MPa inactivated L. rhamnosus ATCC 53103 in a different way. It was observed that the irreversible damage of the membrane-bound transport systems could be largely accounted for the cause of high pressure-induced cell death.
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the protective effect of monosodium glutamate on survival of Lactobacillus rhamnosus gg and Lactobacillus rhamnosus e 97800 e800 strains during spray drying and storage in trehalose containing powders
2009Co-Authors: Elizabeth Oluwaseun Sunnyroberts, Dietrich KnorrAbstract:Abstract The use of trehalose as a means of preserving Lactobacillus rhamnosus GG (LGG) and L. rhamnosus E-97800 (E800) during spray-drying and the effects of incorporated monosodium glutamate (MSG) in the carrier medium on the survival rates during drying and storage were examined. E800 was more resistant to heat than LGG in 20%, w/w, trehalose; the d -values at 65 °C were 14 s and 5.1 s, respectively. An air outlet temperature of 65–70 °C was taken as optimal for the drying process, as the resultant moisture levels in trehalose containing these bacteria were 4.1% (w/w) and 3.79% (w/w) with corresponding viable counts of 3.65 × 108 cfu mL−1 and 1.80 × 109 cfu mL−1, respectively. The presence of MSG increased the final viable counts of LGG and E800 to 3.05 × 109 cfu mL−1 and 1.30 × 109 cfu mL−1, respectively. Survival of LGG and E800 remained constant at a minimum level of ∼108 cfu mL−1 during storage at 25 °C in trehalose–MSG medium.
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cellular injuries and storage stability of spray dried Lactobacillus rhamnosus gg
2005Co-Authors: Edwin Ananta, Marcus Volkert, Dietrich KnorrAbstract:The objective of this work was to evaluate the applicability of spray drying in the production of skim milk-based preparations containing probiotic bacteria Lactobacillus rhamnosus GG (ATCC 53103). Furthermore, oligofructose-based or polydextrose-based prebiotic substances were also included in the carrier matrix to assess their protection capacity. When reconstituted, skim milk was used as a spray drying carrier; a microbial survival rate of 60% was achieved at an outlet temperature of 80 °C. Partial substitution of the solids content of the reconstituted skim milk by prebiotic substances also resulted in a high level of survival. However, the storage stability of the dried powder was reduced as the amount of skim milk solids in the carrier was lowered. The spray drying media were further calorimetrically characterized in terms of their glass transition temperatures so as to evaluate the contribution of glassy state on the maintenance of bacterial survival during storage. Although all evaluated carriers were in the glassy state, differences were observed in their capacity to confer protection on the probiotic bacteria. Flow cytometric assessment in combination with functional dyes was applied as a diagnostic tool to evaluate the type of cellular injuries which occurred upon spray-drying. Cell death was caused mainly by damage to cell membranes and the degree of membrane disintegration increased progressively as the outlet temperatures increased.
Sami Nikoskelainen - One of the best experts on this subject based on the ideXlab platform.
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immune enhancement in rainbow trout oncorhynchus mykiss by potential probiotic bacteria Lactobacillus rhamnosus
2003Co-Authors: Sami Nikoskelainen, Seppo Salminen, Arthur C Ouwehand, Goran Bylund, Esamatti LiliusAbstract:Abstract The present study assessed the immune enhancement of fish by a lactic acid bacterium (LAB) Lactobacillus rhamnosus (ATCC 53103). The bacterium was administered orally at five different doses 7.9×10 4 (LAB4), 2.1×10 6 (LAB6), 2.8×10 8 (LAB8), 1.9×10 10 (LAB10) and 9.7×10 10 (LAB11) CFU/g feed to rainbow trout for two weeks and the feed was changed to un-supplemented diet. From the onset of feeding supplemented diets at 1, 2, 3 and 4 weeks, blood and mucus samples were taken. During the LAB feeding period L. rhamnosus persisted in the fish intestine and in the tank water in high numbers. However, L. rhamnosus disappeared from the intestine, skin mucus and tank water within one week after the change to the non-supplemented feed. In comparison to untreated control fish, respiratory burst activity of blood cells was raised significantly in the LAB4 treated group on week 2. Serum-mediated killing of Escherichia coli was increased significantly in group LAB6 on week 2. Serum immunoglobulin levels were significantly raised only in LAB8 group on week 1 and in LAB4 and LAB8 at the end of the trial. The results show that rainbow trout immune parameters were enhanced by using probiotic bacteria.
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protection of rainbow trout oncorhynchus mykiss from furunculosis by Lactobacillus rhamnosus
2001Co-Authors: Seppo Salminen, Sami Nikoskelainen, Arthur C Ouwehand, Goran BylundAbstract:The present study aimed to investigate the potential probiotic properties in fish of a lactic acid bacterium intended for human use: Lactobacillus rhamnosus (ATCC 53103). A probiotic for human use was specifically chosen since it is known to be safe for human use, which is of major importance because the fish are meant for human consumption. The bacterium was administered at two different doses (109 and 1012 CFU/g feed) to rainbow trout for 51 days. Sixteen days after the start of the Lactobacillus feeding, the fish were challenged with Aeromonas salmonicida ssp. salmonicida, which causes furunculosis. During the challenge trial the mortality was monitored. L. rhamnosus reduced the fish mortality significantly, from 52.6% in the control to 18.9% and 46.3% in the 109 CFU/g feed and the 1012 CFU/g feed groups, respectively. From this, it was concluded that the tested strain may be a promising probiotic for fish without subsequent risk for human consumption.
Seppo Salminen - One of the best experts on this subject based on the ideXlab platform.
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probiotic Lactobacillus rhamnosus gg therapy and microbiological programming in infantile colic a randomized controlled trial
2015Co-Authors: Anna Partty, Seppo Salminen, Liisa Lehtonen, Marko Kalliomaki, Erika IsolauriAbstract:Probiotic Lactobacillus rhamnosus GG therapy and microbiological programming in infantile colic: a randomized, controlled trial
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impact of orally administered lozenges with Lactobacillus rhamnosus gg and bifidobacterium animalis subsp lactis bb 12 on the number of salivary mutans streptococci amount of plaque gingival inflammation and the oral microbiome in healthy adults
2015Co-Authors: Aino Toiviainen, Heli Jalasvuori, Emilia Lahti, Ulvi Kahraman Gursoy, Seppo Salminen, Margherita Fontana, Susan E Flannagan, George Eckert, Alexis Kokaras, Bruce J PasterAbstract:Objectives The aim was to evaluate the effects of orally administered Lactobacillus rhamnosus GG (LGG) and Bifidobacterium animalis subsp. lactis BB-12 (BB-12) on the number of salivary mutans streptococci (MS), amount of plaque, gingival inflammation and the oral microbiota in healthy young adults.
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binding of aflatoxin b1 to cell wall components of Lactobacillus rhamnosus strain gg
2004Co-Authors: Sampo J Lahtinen, Seppo Salminen, Arthur C Ouwehand, Carolyn Haskard, J T AhokasAbstract:The surface of Lactobacillus rhamnosus strain GG (LGG) has previously been shown to bind aflatoxin B1 (AFB1) effectively, it being a food-borne carcinogen produced by certain species of Aspergillus fungi. To establish which components of the cell envelope are involved in the AFB1 binding process, exopolysaccharides and a cell wall isolate containing peptidoglycan were extracted from LGG and its AFB1 binding properties were tested. LGG was also subjected to various enzymatic and chemical treatments and their effects on the binding of AFB1 by LGG were examined. No evidence was found for exopolysaccharides, cell wall proteins, Ca2+ or Mg2+ being involved in AFB1 binding. The AFB1 binding activity of the cell wall isolate indicates that AFB1 binds to the cell wall peptidoglycan of LGG or compounds tightly associated with the peptidoglycan.
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immune enhancement in rainbow trout oncorhynchus mykiss by potential probiotic bacteria Lactobacillus rhamnosus
2003Co-Authors: Sami Nikoskelainen, Seppo Salminen, Arthur C Ouwehand, Goran Bylund, Esamatti LiliusAbstract:Abstract The present study assessed the immune enhancement of fish by a lactic acid bacterium (LAB) Lactobacillus rhamnosus (ATCC 53103). The bacterium was administered orally at five different doses 7.9×10 4 (LAB4), 2.1×10 6 (LAB6), 2.8×10 8 (LAB8), 1.9×10 10 (LAB10) and 9.7×10 10 (LAB11) CFU/g feed to rainbow trout for two weeks and the feed was changed to un-supplemented diet. From the onset of feeding supplemented diets at 1, 2, 3 and 4 weeks, blood and mucus samples were taken. During the LAB feeding period L. rhamnosus persisted in the fish intestine and in the tank water in high numbers. However, L. rhamnosus disappeared from the intestine, skin mucus and tank water within one week after the change to the non-supplemented feed. In comparison to untreated control fish, respiratory burst activity of blood cells was raised significantly in the LAB4 treated group on week 2. Serum-mediated killing of Escherichia coli was increased significantly in group LAB6 on week 2. Serum immunoglobulin levels were significantly raised only in LAB8 group on week 1 and in LAB4 and LAB8 at the end of the trial. The results show that rainbow trout immune parameters were enhanced by using probiotic bacteria.
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protection of rainbow trout oncorhynchus mykiss from furunculosis by Lactobacillus rhamnosus
2001Co-Authors: Seppo Salminen, Sami Nikoskelainen, Arthur C Ouwehand, Goran BylundAbstract:The present study aimed to investigate the potential probiotic properties in fish of a lactic acid bacterium intended for human use: Lactobacillus rhamnosus (ATCC 53103). A probiotic for human use was specifically chosen since it is known to be safe for human use, which is of major importance because the fish are meant for human consumption. The bacterium was administered at two different doses (109 and 1012 CFU/g feed) to rainbow trout for 51 days. Sixteen days after the start of the Lactobacillus feeding, the fish were challenged with Aeromonas salmonicida ssp. salmonicida, which causes furunculosis. During the challenge trial the mortality was monitored. L. rhamnosus reduced the fish mortality significantly, from 52.6% in the control to 18.9% and 46.3% in the 109 CFU/g feed and the 1012 CFU/g feed groups, respectively. From this, it was concluded that the tested strain may be a promising probiotic for fish without subsequent risk for human consumption.
Sarah Lebeer - One of the best experts on this subject based on the ideXlab platform.
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Towards a better understanding of Lactobacillus rhamnosus GG - host interactions
2014Co-Authors: Marijke E Segers, Sarah LebeerAbstract:Lactobacillus rhamnosus GG (LGG) is one of the most widely used probiotic strains. Various health effects are well documented including the prevention and treatment of gastro-intestinal infections and diarrhea, and stimulation of immune responses that promote vaccination or even prevent certain allergic symptoms. However, not all intervention studies could show a clinical benefit and even for the same conditions, the results are not univocal. Clearly, the host phenotype governed by age, genetics and environmental factors such as the endogenous microbiota, plays a role in whether individuals are responders or non-responders. However, we believe that a detailed knowledge of the bacterial physiology and the LGG molecules that play a key role in its host-interaction capacity is crucial for a better understanding of its potential health benefits. Molecules that were yet identified as important factors governing host interactions include its adhesive pili or fimbriae, its lipoteichoic acid molecules, its major secreted proteins and its galactose-rich exopolysaccharides, as well as specific DNA motifs. Nevertheless, future studies are needed to correlate specific health effects to these molecular effectors in LGG, and also in other probiotic strains.
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adhesion and nanomechanics of pili from the probiotic Lactobacillus rhamnosus gg
2013Co-Authors: Prachi Tripathi, Sarah Lebeer, Ingmar Claes, Willem M De Vos, Airi Palva, Audrey Beaussart, David Alsteens, Vincent Dupres, Ingemar Von Ossowski, Jos VanderleydenAbstract:Knowledge of the mechanisms by which bacterial pili adhere to host cells and withstand external forces is critical to our understanding of their functional roles and offers exciting avenues in biomedicine for controlling the adhesion of bacterial pathogens and probiotics. While much progress has been made in the nanoscale characterization of pili from Gram-negative bacteria, the adhesive and mechanical properties of Gram-positive bacterial pili remain largely unknown. Here, we use single-molecule atomic force microscopy to unravel the binding mechanism of pili from the probiotic Gram-positive bacterium Lactobacillus rhamnosus GG (LGG). First, we show that SpaC, the key adhesion protein of the LGG pilus, is a multifunctional adhesin with broad specificity. SpaC forms homophilic trans-interactions engaged in bacterial aggregation and specifically binds mucin and collagen, two major extracellular components of host epithelial layers. Homophilic and heterophilic interactions display similar binding strengths and dissociation rates. Next, pulling experiments on living bacteria demonstrate that LGG pili exhibit two unique mechanical responses, that is, zipper-like adhesion involving multiple SpaC molecules distributed along the pilus length and nanospring properties enabling pili to resist high force. These mechanical properties may represent a generic mechanism among Gram-positive bacterial pili for strengthening adhesion and withstanding shear stresses in the natural environment. The single-molecule experiments presented here may help us to design molecules capable of promoting or inhibiting bacterial-host interactions. © 2013 American Chemical Society.
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lipoteichoic acid is an important microbe associated molecular pattern of Lactobacillus rhamnosus gg
2012Co-Authors: Ingmar Claes, Jos Vanderleyden, Marijke Segers, Tine Verhoeven, Michiel Dusselier, Bert F Sels, Sigrid C J De Keersmaecker, Sarah LebeerAbstract:Background Probiotic bacteria are increasingly used as immunomodulatory agents. Yet detailed molecular knowledge on the immunomodulatory molecules of these bacteria is lagging behind. Lipoteichoic acid (LTA) is considered a major microbe-associated molecular pattern (MAMP) of Gram-positive bacteria. However, many details and quantitative data on its immune signalling capacity are still unknown, especially in beneficial bacteria. Recently, we have demonstrated that a dltD mutant of the model probiotic Lactobacillus rhamnosus GG (LGG), having modified LTA molecules, has an enhanced probiotic efficacy in a DSS-induced colitis model as compared to wild-type.
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Impact of luxS and suppressor mutations on the gastrointestinal transit of Lactobacillus rhamnosus GG.
2008Co-Authors: Sarah Lebeer, Ingmar Claes, Jos Vanderleyden, Tine Verhoeven, Chong Shen, Ivo Lambrichts, Jan Ceuppens, Sigrid C J De KeersmaeckerAbstract:It is generally believed that probiotic bacteria need to survive gastrointestinal transit to exert a health-promoting effect. In this study, a genuine luxS mutant and a luxS mutant containing unknown suppressor mutations of the probiotic strain Lactobacillus rhamnosus GG were compared to the wild type for survival and persistence in the murine gastrointestinal tract. The LuxS enzyme, catalyzing the production of the autoinducer-2 signaling molecule, also forms an integral part of the activated methyl cycle and the metabolism of methionine and cysteine. The genuine luxS mutant CMPG5412 showed drastically reduced persistence in mice, which was related to less survival in simulated gastric juice, indicating that LuxS metabolism is crucial for the gastric stress resistance of L. rhamnosus GG. The suppressor mutations in the other luxS mutant, CMPG5413, appear to compensate for the metabolic defects of the luxS mutation and to restore the resistance to gastric juice but cause a defect in adherence, biofilm formation, and exopolysaccharide production. The shorter residence time of this suppressor mutant in the murine gastrointestinal tract indicates a role for biofilm formation and exopolysaccharides in the persistence capacity of L. rhamnosus GG.
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impact of environmental and genetic factors on biofilm formation by the probiotic strain Lactobacillus rhamnosus gg
2007Co-Authors: Sarah Lebeer, Jos Vanderleyden, Tine Verhoeven, Monica Perea Velez, Sigrid C J De KeersmaeckerAbstract:Lactobacillus rhamnosus GG (ATCC 53103) is one of the clinically best-studied probiotic organisms. Moreover, L. rhamnosus GG displays very good in vitro adherence to epithelial cells and mucus. Here, we report that L. rhamnosus GG is able to form biofilms on abiotic surfaces, in contrast to other strains of the Lactobacillus casei group tested under the same conditions. Microtiter plate biofilm assays indicated that in vitro biofilm formation by L. rhamnosus GG is strongly modulated by culture medium factors and conditions related to the gastrointestinal environment, including low pH; high osmolarity; and the presence of bile, mucins, and nondigestible polysaccharides. Additionally, phenotypic analysis of mutants affected in exopolysaccharides (wzb), lipoteichoic acid (dltD), and central metabolism (luxS) showed their relative importance in biofilm formation by L. rhamnosus GG.
