Inhibition of Helicobacter pylori infection by bovine milk glycoconjugates in a BALB/cA mouse model

Abstract

The attachment of Helicobacter pylori to the human gastric mucosa is a complex process involving several speci®c structures recognised by the cell surface receptors. Sialylated multivalent high mol. wt glycoproteins have been shown to inhibit H. pylori sialic acidspeci®c haemagglutination. This study explored whether sialylated glycoconjugates from bovine milk could inhibit an experimental H. pylori infection in a mouse model. BALB=cA mice (6±8 weeks old) were inoculated with a mouse-passaged H. pylori strain 317p. Four weeks after infection the mice were given lactoferrin (iron-free LF or 20% iron-saturated LF) or bovine milk fat globule membrane fractions (MFGM or defatted MFGM) orally (400 mg=kg body weight) once daily for 10 days and then killed to examine for bacterial colonisation and gastritis. Mice treated with iron-free LF, 20% iron-saturated LF, MFGM or defatted MFGM showed 30%, 10%, 20% or 20% healing rates, respectively, when compared with the H. pylori-infected control. Gastric colonisation by H. pylori was remarkably decreased in all mice treated with bovine milk glycoconjugates and the in¯ammation score was also signi®cantly lower in treated mice than in infected control animals. The fact that there was no signi®cant difference between iron-free LF and iron-saturated LF or MFGM and defatted MFGM suggested that iron is not crucial for inhibition of H. pylori by lactoferrin and that the lipid part of MFGM is not important for anti-H. pylori activity. In conclusion, bovine milk glycoconjugates showed potencies to inhibit H. pylori infection in this mouse model and, therefore, could be considered as candidates for non-antibiotic strategies against H. pylori infection in man.

Use of Proteomic Methodology for the Characterization of Human Milk Fat Globular Membrane Proteins

“…For instance, lactotransferrin is only partly saturated with iron in its native state and can therefore have a bacteriostatic effect by competing with bacteria for iron (8). Lactotransferrin may also function as an antibiotic agent by virtue of its structural properties (13). The glycosylation of lactotransferrin has been characterized previously (14) and differs from that normally found in serum transferrin.…”

PspA Protects Streptococcus pneumoniae from Killing by Apolactoferrin, and Antibody to PspA Enhances Killing of Pneumococci by Apolactoferrin

“…The bacteriostatic activity of ALF is due in part to its iron chelating ability, which can deplete iron and restrict bacterial growth (48). ALF is also bactericidal against a wide range of bacteria, including Escherichia coli, Vibrio cholerae, Streptococcus mutans, and S. pneumoniae (4,24,58). The bactericidal activity of ALF is associated with the N-terminal 47 amino acids of the protein, which is part of the N-lobe (55).…”

Bovine lactoferrin is effective to suppress Helicobacter pylori colonization in the human stomach: A randomized, double-blind, placebo-controlled study

“…11 The administration of bLF to H. pylori-infected mice resulted in marked decrease of bacterial colonization, attachment, and inflammation irrespective of iron-free or partially iron-saturated preparations. 12,13 In humans with H. pylori infection, Di Mario et al showed that bLF combined in a triple eradication regimen (rabeprazole, clarithromycin, and tinidazole) significantly improved the eradication rate. 14 In the present study, we investigated the efficacy of a single administration of bLF in a randomized, double-blind, placebo-controlled trial.…”