title: Antagonistic activity against Helicobacter infection in vitro and in vivo by the human Lactobacillus acidophilus strain LB.
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 pylori in 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 the H. 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.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, CJF 94. 07, UFR de Pharmacie, Université Paris XI, F-92296 Châtenay-Malabry, France.
authors.forename: M H
authors.initials: MH
authors.lastname: Coconnier
authors.forename: V
authors.initials: V
authors.lastname: Lievin
authors.forename: E
authors.initials: E
authors.lastname: Hemery
authors.forename: A L
authors.initials: AL
authors.lastname: Servin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000633:toxicity; D001422:Bacterial Adhesion; D002460:Cell Line; D005753:Gastric Mucosa / Q000201:enzymology / Q000473:pathology*; D016998:Helicobacter / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D016481:Helicobacter Infections / Q000201:enzymology / Q000473:pathology / Q000628:therapy*; D016480:Helicobacter pylori / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D006801:Humans; D007779:Lactobacillus acidophilus / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008826:Microbial Sensitivity Tests; D008854:Microscopy, Electron; D013997:Time Factors; D014510:Urease / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D014510:Urease