scholarly journals Antagonistic Activity againstHelicobacter Infection In Vitro and In Vivo by the HumanLactobacillus acidophilus Strain LB

1998 ◽  
Vol 64 (11) ◽  
pp. 4573-4580 ◽  
Author(s):  
Marie-Helene Coconnier ◽  
Vanessa Lievin ◽  
Elisabeth Hemery ◽  
Alain L. Servin
Keyword(s):  
Lactobacillus Acidophilus ◽  
Urease Activity ◽  
Culture Supernatant ◽  
Oral Treatment ◽  
Antagonistic Activity ◽  
Antibacterial Substance ◽  
Helicobacter Felis ◽  
H Pylori

ABSTRACT The purpose of the present study was to examine the activity of the human Lactobacillus acidophilus strain LB, which secretes an antibacterial substance(s) against Helicobacter pyloriin vitro and in vivo. The spent culture supernatant (SCS) of the strain LB (LB-SCS) dramatically decreased the viability of H. pylori in vitro independent of pH and lactic acid levels. Adhesion of H. pylori to the cultured human mucosecreting HT29-MTX cells decreased in parallel with the viability of H. pylori. In conventional mice, oral treatment with the LB-SCS protected against infection with Helicobacter felis. Indeed, at both 8 and 49 days post-LB-SCS treatment (29 and 70 days postinfection), inhibition of stomach colonization by H. felis was observed, and no evidence of gastric histopathological lesions was found. LB-SCS treatment inhibits theH. pylori urease activity in vitro and in H. pylori that remained associated with the cultured human mucosecreting HT29-MTX cells. Moreover, a decrease in urease activity was detected in the stomach of the mice infected with H. felis and treated with LB-SCS.

scholarly journals Antibacterial effect of the adhering human Lactobacillus acidophilus strain LB.

1997 ◽  
Vol 41 (5) ◽  
pp. 1046-1052 ◽  
Author(s):  
M H Coconnier ◽  
V Liévin ◽  
M F Bernet-Camard ◽  
S Hudault ◽  
A L Servin
Keyword(s):  
Lactobacillus Acidophilus ◽  
Culture Supernatant ◽  
Oral Treatment ◽  
Shigella Flexneri ◽  
Lactic Acid Production ◽  
Heat Stable ◽  
Wide Range ◽  
Production Activity ◽  
Acidic Conditions

The spent culture supernatant of the human Lactobacillus acidophilus strain LB produces an antibacterial activity against a wide range of gram-negative and gram-positive pathogens. It decreased the in vitro viability of Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Shigella flexneri, Escherichia coli, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. In contrast, it did not inhibit lactobacilli and bifidobacteria. The activity was heat stable and relatively sensitive to enzymatic treatments and developed under acidic conditions. The antimicrobial activity was independent of lactic acid production. Activity against S. typhimurium SL1344 infecting human cultured intestinal Caco-2 cells was observed as it was in the conventional C3H/He/oujco mouse model with S. typhimurium C5 infection and oral treatment with the LB spent culture supernatant.

scholarly journals Essential Oils as Components of a Diet-Based Approach to Management of Helicobacter Infection

2003 ◽  
Vol 47 (10) ◽  
pp. 3240-3246 ◽  
Author(s):  
G. E. Bergonzelli ◽  
D. Donnicola ◽  
N. Porta ◽  
I. E. Corthésy-Theulaz
Keyword(s):  
Essential Oils ◽  
Seed Oil ◽  
Oral Treatment ◽  
Food Additives ◽  
Peptic Ulcers ◽  
Carrot Seed ◽  
Bactericidal Activities ◽  
H Pylori

ABSTRACT An increased density of Helicobacter pylori in the gastric mucosa can be associated with more severe gastritis and an increased incidence of peptic ulcers. Therefore, people with asymptomatic gastritis would certainly benefit from a nutritional approach to help them manage the infection and therefore decrease the risk of development of associated pathologies. We analyzed the activities of 60 essential oils against H. pylori P1 and identified 30 oils that affected growth, with in vitro inhibition zones ranging between 0.7 and 6.3 cm in diameter. We further analyzed the effects of 16 oils with different activities on H. pylori P1 viability. Fifteen showed strong bactericidal activities, with minimal bactericidal concentrations after 24 h ranging from 0.02 to 0.1 g/liter at pH 7.4. Even though slight variations in activities were observed, the essential oils that displayed the strongest bactericidal potentials against H. pylori P1 were also active against other Helicobacter strains tested. Among the pure constituents of different essential oils tested, carvacrol, isoeugenol, nerol, citral, and sabinene exhibited the strongest anti-H. pylori activities. Although oral treatment of H. pylori SS1-infected mice with carrot seed oil did not result in significant decreases in the bacterial loads in the treated animals compared to those in the control animals, in all experiments performed, the infection was cleared in 20 to 30% of carrot seed oil-treated animals. Our results indicate that essential oils are unlikely to be efficient anti-Helicobacter agents in vivo. However, their effects may not be irrelevant if one plans to use them as food additives to complement present therapies.

scholarly journals Helicobacter pylori Containing Only Cytoplasmic Urease Is Susceptible to Acid

1998 ◽  
Vol 66 (11) ◽  
pp. 5060-5066 ◽  
Author(s):  
Partha Krishnamurthy ◽  
Mary Parlow ◽  
Jason B. Zitzer ◽  
Nimish B. Vakil ◽  
Harry L. T. Mobley ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Acid Resistance ◽  
Etiologic Agent ◽  
Stationary Phase Culture ◽  
Colonization Factor ◽  
Acid Environment ◽  
H Pylori

ABSTRACT Helicobacter pylori, an important etiologic agent in a variety of gastroduodenal diseases, produces large amounts of urease as an essential colonization factor. We have demonstrated previously that urease is located within the cytoplasm and on the surface of H. pylori both in vivo and in stationary-phase culture. The purpose of the present study was to assess the relative contributions of cytoplasmic and surface-localized urease to the ability of H. pylori to survive exposure to acid in the presence of urea. Toward this end, we compared the acid resistance in vitro of H. pylori cells which possessed only cytoplasmic urease to that of bacteria which possessed both cytoplasmic and surface-localized or extracellular urease. Bacteria with only cytoplasmic urease activity were generated by using freshly subcultured bacteria or by treating repeatedly subcultured H. pylori with flurofamide (1 μM), a potent, but poorly diffusible urease inhibitor. H. pyloriwith cytoplasmic and surface-located urease activity survived in an acid environment when 5 mM urea was present. In contrast, H. pylori with only cytoplasmic urease shows significantly reduced survival when exposed to acid in the presence of 5 mM urea. Similarly,Escherichia coli SE5000 expressing H. pyloriurease and the Ni2+ transport protein NixA, which expresses cytoplasmic urease activity at levels similar to those in wild-typeH. pylori, survived minimally when exposed to acid in the presence of 5 to 50 mM urea. We conclude that cytoplasmic urease activity alone is not sufficient (although cytoplasmic urease activity is likely to be necessary) to allow survival of H. pyloriin acid; the activity of surface-localized urease is essential for resistance of H. pylori to acid under the assay conditions used. Therefore, the mechanism whereby urease becomes associated with the surface of H. pylori, which involves release of the enzyme from bacteria due to autolysis followed by adsorption of the enzyme to the surface of intact bacteria (“altruistic autolysis”), is essential for survival of H. pylori in an acid environment. The ability of H. pylori to survive exposure to low pH is likely to depend on a combination of both cytoplasmic and surface-associated urease activities.

scholarly journals The Helicobacter pylori UreI Protein Is Not Involved in Urease Activity but Is Essential for Bacterial Survival In Vivo

1998 ◽  
Vol 66 (9) ◽  
pp. 4517-4521 ◽  
Author(s):  
Stéphane Skouloubris ◽  
Jean-Michel Thiberge ◽  
Agnès Labigne ◽  
Hilde De Reuse
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Saline Solution ◽  
Integral Membrane Protein ◽  
Bacterial Survival ◽  
Acidic Conditions ◽  
H Pylori ◽  
Phosphate Buffered Saline

ABSTRACT We produced defined isogenic Helicobacter pylori ureImutants to investigate the function of UreI, the product of one of the genes of the urease cluster. The insertion of a catcassette had a strong polar effect on the expression of the downstream urease genes, resulting in very weak urease activity. Urease activity, measured in vitro, was normal in a strain in which ureI was almost completely deleted and replaced with a nonpolar cassette. In contrast to previous reports, we thus found that the product ofureI was not necessary for the synthesis of active urease. Experiments with the mouse-adapted H. pylori SS1 strain carrying the nonpolar ureI deletion showed that UreI is essential for H. pylori survival in vivo and/or colonization of the mouse stomach. The replacement of ureIwith the nonpolar cassette strongly reduced H. pylorisurvival in acidic conditions (1-h incubation in phosphate-buffered saline solution at pH 2.2) in the presence of 10 mM urea. UreI is predicted to be an integral membrane protein and may therefore be involved in a transport process essential for H. pylori survival in vivo.

scholarly journals Helicobacter pylori rocF Is Required for Arginase Activity and Acid Protection In Vitro but Is Not Essential for Colonization of Mice or for Urease Activity

1999 ◽  
Vol 181 (23) ◽  
pp. 7314-7322 ◽  
Author(s):  
David J. McGee ◽  
Fiona J. Radcliff ◽  
George L. Mendz ◽  
Richard L. Ferrero ◽  
Harry L. T. Mobley
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Geometric Mean ◽  
Acid Exposure ◽  
Arginase Activity ◽  
Gene Encoding ◽  
Acid Sensitivity ◽  
H Pylori

ABSTRACT Arginase of the Helicobacter pylori urea cycle hydrolyzes l-arginine to l-ornithine and urea.H. pylori urease hydrolyzes urea to carbon dioxide and ammonium, which neutralizes acid. Both enzymes are involved inH. pylori nitrogen metabolism. The roles of arginase in the physiology of H. pylori were investigated in vitro and in vivo, since arginase in H. pylori is metabolically upstream of urease and urease is known to be required for colonization of animal models by the bacterium. The H. pylori genehp1399, which is orthologous to the Bacillus subtilis rocF gene encoding arginase, was cloned, and isogenic allelic exchange mutants of three H. pylori strains were made by using two different constructs: 236-2 androcF::aphA3. In contrast to wild-type (WT) strains, all rocF mutants were devoid of arginase activity and had diminished serine dehydratase activity, an enzyme activity which generates ammonium. Compared with WT strain 26695 of H. pylori, the rocF::aphA3 mutant was ∼1,000-fold more sensitive to acid exposure. The acid sensitivity of the rocF::aphA3 mutant was not reversed by the addition of l-arginine, in contrast to the WT, and yielded a ∼10,000-fold difference in viability. Urease activity was similar in both strains and both survived acid exposure equally well when exogenous urea was added, indicating that rocF is not required for urease activity in vitro. Finally, H. pylorimouse-adapted strain SS1 and the 236-2 rocF isogenic mutant colonized mice equally well: 8 of 9 versus 9 of 11 mice, respectively. However, the rocF::aphA3 mutant of strain SS1 had moderately reduced colonization (4 of 10 mice). The geometric mean levels of H. pylori recovered from these mice (in log10 CFU) were 6.1, 5.5, and 4.1, respectively. Thus,H. pylori rocF is required for arginase activity and is crucial for acid protection in vitro but is not essential for in vivo colonization of mice or for urease activity.

scholarly journals Novel in vitro and in vivo anti-Helicobacter pylori effects of pomegranate peel ethanol extract

2021 ◽  
Vol 14 (1) ◽  
pp. 120-128
Author(s):  
Amal Mayyas ◽  
Mohammad Abu-Sini ◽  
Rula Amr ◽  
Rand T. Akasheh ◽  
Waleed Zalloum ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Synergistic Effect ◽  
Oral Treatment ◽  
Antimicrobial Properties ◽  
Complementary Therapy ◽  
Gastric Ulcers ◽  
Pomegranate Peel ◽  
H Pylori

Background and Aim: Interest in plants with antimicrobial properties has been revived due to emerging problems associated with using antibiotics to eradicate Helicobacter pylori. Accordingly, this study aims to assess the antibacterial effects of Punica granatum and the possible synergistic effect of its extract along with metronidazole against H. pylori. Materials and Methods: Pomegranate peel ethanol extracts (PPEE) was tested against a control strain of H. pylori (NCTC 11916) in vitro and in vivo in female Wistar rats. Moreover, the synergistic effect of PPEE in combination with metronidazole was tested in vitro. Results: The PPEE exhibited a remarkable activity against H. pylori with a minimum inhibitory concentration (MIC) of 0.156 mg/mL. Furthermore, the extract exhibited a pronounced urease inhibitory activity (IC50 ∼6 mg/mL) against the tested strain. A synergistic effect between PPEE and metronidazole was also observed (fractional inhibitory concentrations <0.5). Oral treatment of rats with PPEE for 8 days produced a significant reduction in H. pylori gastritis and a significant decrease in both lymphocytic and positive chronicity. Conclusion: Pomegranate extract is probably safe and represents a potential alternative and complementary therapy for reducing H. pylori associated with gastric ulcers.

scholarly journals The human Lactobacillus acidophilus strain LA1 secretes a nonbacteriocin antibacterial substance(s) active in vitro and in vivo.

1997 ◽  
Vol 63 (7) ◽  
pp. 2747-2753 ◽  
Author(s):  
M F Bernet-Camard ◽  
V Liévin ◽  
D Brassart ◽  
J R Neeser ◽  
A L Servin ◽  
...  
Keyword(s):  
Lactobacillus Acidophilus ◽  
Antibacterial Substance

scholarly journals In Vivo Complementation of ureB Restores the Ability of Helicobacter pylori To Colonize

2002 ◽  
Vol 70 (2) ◽  
pp. 771-778 ◽  
Author(s):  
Kathryn A. Eaton ◽  
Joanne V. Gilbert ◽  
Elizabeth A. Joyce ◽  
Amy E. Wanken ◽  
Tracy Thevenot ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Wild Type ◽  
Colonization Density ◽  
H Pylori ◽  
Epithelial Lesions ◽  
Derivatives Of ◽  
Colonizing Ability

ABSTRACT The objective of this study was to determine (i) if complementation of ureB-negative Helicobacter pylori restores colonization and (ii) if urease is a useful reporter for promoter activity in vivo. Strains used were M6, M6ΔureB, and 10 recombinant derivatives of M6 or M6ΔureB in which urease expression was under the control of different H. pylori promoters. Mice were orally inoculated with either the wild type or one of the mutant strains, and colonization, in vivo urease activity, and extent of gastritis were determined. Of eight M6ΔureB recombinants tested, four colonized mice. Of those, three had the highest in vitro urease activity of any of the recombinants, significantly different from that of the noncolonizing mutants. The fourth colonizing recombinant, with ureB under control of the cag-15 promoter, had in vitro urease activity which did not differ significantly from the noncolonizing strains. In vivo, urease activities of the four colonizing transformants and the wild-type control were indistinguishable. There were no differences in gastritis or epithelial lesions between mice infected with M6 and those infected with the transformants. These results demonstrate that recovery of urease activity can restore colonizing ability to urease-negative H. pylori. They also suggest that cag-15 is upregulated in vivo, as was previously suggested by demonstrating that it is upregulated upon contact with epithelial cells. Finally, our results suggest that total urease activity and colonization density do not contribute to gastritis due to H. pylori.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

VIABILITAS LACTOBACILLUS ACIDOPHILUS DALAM PAKAN AYAM BROILER UNTUK MENGHAMBAT PENYAKIT PULLORUM

2018 ◽  
Vol 16 (1) ◽  
pp. 47-52
Author(s):  
Ida Ningrumsari ◽  
Lina Herlinawati
Keyword(s):  
Lactobacillus Acidophilus ◽  
Salmonella Pullorum

Penyakit pullorum dikenal dengan nama berak kapur atau berak putih (Bacilary white Diarrchae)yang banyak menimbulkan kerugian bagi peternak, oleh karena itu dilakukan penelitian dengantujuan untuk mengetahui ketahanan (viabilitas) L acidophilus dalam pakan ayam broiler untukmenghambat penyakit pullorum. Rancangan penelitian menggunakan eksperimentallaboratorium, persamaan kuadratik dan Rancangan Acak Lengkap (RAL) 1 faktorial dengan polaperlakuan konsentrasi L acidophilus dari 106-109 . Pertumbuhan terbaik dari L acidophilus yaituyang berumur 12 jam digunakan untuk menghambat Salmonella pullorum,sedangkanpertumbuhan S pullorum yang dapat menginfeksi ayam yaitu pada umur 15 jam.KonsentrasiL acidophilus yang dapat menghambat S pullorum secara in vitro yaitu 107, LD50 Salmonellapullorum in vivo ayam broiler pada 108. Viabilitas (ketahanan) L acidophilus dalam pakan bisabertahan hidup di atas 35 hari.

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