Comparative Studies on the Toxicity of Escherichia Coli Lipopolysaccharide Endotoxin in Various Animal Species

Berczi, István; Bertók, L; Bereznai, T.

doi:10.1139/m66-143

Cited by 244 publications

(123 citation statements)

References 0 publications

Supporting

Mentioning

112

Contrasting

Unclassified

Order By: Relevance

“…This is consistent with previous reports showing that the LPS structure is altered more efficiently by peptide dimers than the respective single monomers (65). Overall, the two synergistic effects between AMPs from the same frog specimen can in part explain the ability of amphibia to protect themselves from infections of a large repertoire of microorganisms as well as their lacking sensitivity to the toxic effects of LPS (66,67). In addition, these studies should help in the future development of non-single peptide-based therapeutic strategies to kill multidrug-resistant Gram-negative bacteria and/or neutralize the effect of their LPS, subsequently released.…”

Section: Discussionsupporting

confidence: 92%

Lipopolysaccharide, a Key Molecule Involved in the Synergism between Temporins in Inhibiting Bacterial Growth and in Endotoxin Neutralization

Mangoni

Epand

Rosenfeld

et al. 2008

Journal of Biological Chemistry

View full text Add to dashboard Cite

Lipopolysaccharide (LPS) is the major structural component of the outer membrane of Gram-negative bacteria and shields them from a variety of host defense factors, including antimicrobial peptides (AMPs). LPS is also recognized by immune cells as a pathogen-associated molecular pattern and stimulates them to secrete pro-inflammatory cytokines that, in extreme cases, lead to a harmful host response known as septic shock. Previous studies have revealed that a few isoforms of the AMP temporin, produced within the same frog specimen, can synergize to overcome bacterial resistance imposed by the physical barrier of LPS. Here we found that temporins can synergize in neutralizing the LPS-induced macrophage activation. Furthermore, the synergism between temporins, to overcome the protective function of LPS as well as its endotoxic effect, depends on the length of the polysaccharide chain of LPS. Importantly, mode of action studies, using spectroscopic and thermodynamic methods, have pointed out different mechanisms underlying the synergism of temporins in antimicrobial and anti-endotoxin activities. To the best of our knowledge, such a dual synergism between isoforms of AMPs from the same species has not been observed before, and it might explain the ability of such amphibians to resist a large repertoire of microorganisms.

show abstract

Section: Discussionsupporting

confidence: 92%

Lipopolysaccharide, a Key Molecule Involved in the Synergism between Temporins in Inhibiting Bacterial Growth and in Endotoxin Neutralization

Mangoni

Epand

Rosenfeld

et al. 2008

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…The rat is normally better able to tolerate large doses of LPS (10-50 mg/kg), given either parenterally or by intraperitoneal injection, with only moderate adverse effects. 21 In the current study it was observed that sham (control) rats could tolerate 2 mg/kg of LPS intraperitoneally without any obvious adverse reactions, and we have previously used doses of up to 20 mg/kg without any appreciable short-term mortality (Unpublished observation, Harry and Moore, December, 1997). By contrast the BDL cirrhotic rats had a marked increase in mortality at the low dose of 0.5 mg/kg of LPS.…”

Section: Discussionmentioning

confidence: 67%

Increased sensitivity to endotoxemia in the bile duct-ligated cirrhotic rat

et al. 1999

View full text Add to dashboard Cite

Sepsis is a common complication of cirrhosis with a high mortality. In this study, we have investigated some of the pathways that may be involved in tissue injury and death. Bile duct-ligated (BDL) cirrhotic and control rats were challenged with lipopolysaccharide (LPS). Sensitivity to LPS was markedly enhanced in the BDL group, and was associated with increased liver injury and mortality. There was a 5-fold constitutive activation of nuclear factor B (NFB) in the liver of BDL rat controls (P F .001), and this was activated further, but to a similar extent, in the liver of both sham and BDL rats after injection of LPS. Plasma tumor necrosis factor ␣ (TNF-␣) increased more markedly in the BDL cirrhotic rats (2,463 ؎ 697 pg/mL in BDL rats versus 401 ؎ 160 pg/mL in the controls at 3 hours; P F .01). Plasma nitrite/nitrate concentrations were increased in the BDL controls at baseline, and increased further after LPS (P F .05), but did not differ from sham controls at 6 hours. Plasma F 2 -isoprostanes increased 6-fold in the cirrhotic rats and 2-fold in the controls (P F .01) indicative of lipid peroxidation. Esterified F 2 -isoprostanes in the liver increased 2-to 3-fold at 1 hour in control and BDL rats, but returned to baseline levels by 3 hours. Esterified F 2 -isoprostanes in the kidney increased by 2-fold in the BDL rats after LPS administration, but remained unchanged in sham controls. We conclude that there is a marked increase in sensitivity to LPS in BDL cirrhotic rats. This is associated with an enhanced TNF-␣ response and increased lipid peroxidation. These may be directly and causally related to mortality. (HEPATOLOGY 1999;30:1198-1205.)Sepsis and associated endotoxemia occur in approximately 40% of hospitalized patients with cirrhosis and is a major cause of death.

show abstract

“…Fish have no or a poor inflammatory immune response to LPS (Berczi et al, 1966;Iliev et al, 2005;Swain et al, 2008). However, there are, to our knowledge, no studies about fish intestinal gut inflammation related to Edwardsiella LPS.…”

Section: Discussionmentioning

confidence: 99%

Mechanisms of intrinsic resistance to antimicrobial peptides of Edwardsiella ictaluri and its influence on fish gut inflammation and virulence

et al. 2013

View full text Add to dashboard Cite

The genus Edwardsiella comprises a genetically distinct taxon related to other members of the family Enterobacteriaceae. It consists of bacteria differing strongly in their biochemical and physiological features, natural habitats, and pathogenic properties. Intrinsic resistance to cationic antimicrobial peptides (CAMPs) is a specific property of the genus Edwardsiella. In particular, Edwardsiella ictaluri, an important pathogen of the catfish (Ictalurus punctatus) aquaculture and the causative agent of a fatal systemic infection, is highly resistant to CAMPs. E. ictaluri mechanisms of resistance to CAMPs are unknown. We hypothesized that E. ictaluri lipopolysaccharide (LPS) plays a role in both virulence and resistance to CAMPs. The putative genes related to LPS oligo-polysaccharide (O-PS) synthesis were in-frame deleted. Individual deletions of wibT, gne and ugd eliminated synthesis of the O-PS, causing auto-agglutination, rough colonies, biofilm-like formation and motility defects. Deletion of ugd, the gene that encodes the UDP-glucose dehydrogenase enzyme responsible for synthesis of UDP-glucuronic acid, causes sensitivity to CAMPs, indicating that UDP-glucuronic acid and its derivatives are related to CAMP intrinsic resistance. E. ictaluri OP-S mutants showed different levels of attenuation, colonization of lymphoid tissues and immune protection in zebrafish (Danio rerio) and catfish. Orally inoculated catfish with O-PS mutant strains presented different degrees of gut inflammation and colonization of lymphoid tissues. Here we conclude that intrinsic resistance to CAMPs is mediated by Ugd enzyme, which has a pleiotropic effect in E. ictaluri influencing LPS synthesis, motility, agglutination, fish gut inflammation and virulence.

show abstract

Comparative Studies on the Toxicity of Escherichia Coli Lipopolysaccharide Endotoxin in Various Animal Species

Cited by 244 publications

References 0 publications

Lipopolysaccharide, a Key Molecule Involved in the Synergism between Temporins in Inhibiting Bacterial Growth and in Endotoxin Neutralization

Lipopolysaccharide, a Key Molecule Involved in the Synergism between Temporins in Inhibiting Bacterial Growth and in Endotoxin Neutralization

Increased sensitivity to endotoxemia in the bile duct-ligated cirrhotic rat

Mechanisms of intrinsic resistance to antimicrobial peptides of Edwardsiella ictaluri and its influence on fish gut inflammation and virulence

Contact Info

Product

Resources

About