The novel beta-defensin DEFB123 prevents lipopolysaccharide-mediated effects in vitro and in vivo.
Defensins are a family of secreted antimicrobial peptides proposed to directly interfere with bacterial membranes. Here we show a functional analysis of the novel beta-defensin DEFB123. A peptide comprising the beta-defensin core region was synthesized and used for our analysis. Like other beta-defensins, DEFB123 exerted antimicrobial activity against a broad spectrum of Gram-positive and Gram-negative bacteria, which was assessed by microbroth dilution assay and radial diffusion zone assay. In addition, the peptide showed lipopolysaccharide (LPS)-binding activity in a Limulus amoebocyte lysate (LAL) assay. Moreover, DEFB123 prevented LPS-induced tumor necrosis factor (TNF)-alpha secretion in a murine monocyte cell line (RAW264.7). Accordingly, DEFB123 abolished LPS- mediated MAPK induction in these cells. Protection against LPS-mediated effects was then investigated in a murine model of acute sepsis. Our experiments show that synthetic beta-defensin DEFB123 prevents LPS-induced mortality in C57BL/6 mice in a therapeutic approach. We propose that the physiological role of beta-defensins may include interference with LPS-action on macrophages, a function formerly thought to be restricted to the family of cathelicidins, a structurally unrelated group of antimicrobial peptides.[1]References
- The novel beta-defensin DEFB123 prevents lipopolysaccharide-mediated effects in vitro and in vivo. Motzkus, D., Schulz-Maronde, S., Heitland, A., Schulz, A., Forssmann, W.G., Jübner, M., Maronde, E. FASEB J. (2006) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg