Search results

Sort By:

Limit search:

Novel properties of antimicrobial peptides.

100%

Kamysz W., Okrój M., Łukasiak J.

2003

vol. 50

issue 2

461-469

Endogenous peptide antibiotics are known as evolutionarily old components of innate immunity. Due to interaction with cell membrane these peptides cause permeabilization of the membrane and lysis of invading microbes. However, some studies proved that antimicrobial peptides are universal multifunctional molecules and their functions extend far beyond simple antibiotics. In this review we present an overview of the general mechanism of action of antimicrobial peptides and discuss some of their additional properties, like antitumour activity, mitogenic activity, role in signal transduction pathways and adaptive immune response.

Antitumor activity of antimicrobial peptides against U937 histiocytic cell line

88%

Koszałka P., Kamysz E., Wejda M., Kamysz W., Bigda J.

We investigated cytotoxic activity of antimicrobial peptides of different origin (both naturally occurring and synthetic), structure and known mechanisms of action against human histiocytic lymphoma cell line U937. The strongest cytotoxic activity against U937 cell line was shown by Pexiganan MSI-78, followed by Citropin 1.1, Protegrin 1 and a synthetic lipopeptide, N-α-palmitoyl-l-lysyl-l-lysine amide (Pal-Lys-Lys-NH2). The cytotoxic activity of the peptides was more dependent on the time of incubation than concentration. Only for the lipopeptide, whose mode of action was restricted to disruption of electric potential of the cell membrane, the correlation between cytotoxicity and concentration was almost linear. The high cytotoxicity of Pexiganan MSI-78, Protegrin 1 and the lipopeptide could be basically explained by their membranolytic activity leading to necrosis. However, in the case of Citropin 1.1, the cell membrane integrity was disrupted only slightly and independently of the peptide concentration. Therefore, some other mechanism of action might be responsible for its strong dose-dependent cytotoxic activity, e.g., membranolytic activity leading to apoptosis. Furthermore, TNF-α production due to LPS (lipopolysaccharide) stimulation was suppressed by the presence of Citropin 1.1, Pexiganan MSI-78 or Protegrin 1, but not by Buforin 2 or the lipopeptide. Our experiments have shown that cytotoxic activity is not limited to some specific molecular structure of a peptide, but rather to the length of the peptide chain as it is likely to affect the efficiency of the tumor cell membrane disruption and interaction with LPS.

Refine search results

2 Acta Biochimica Polonica

1 2011

1 2003

2 Kamysz W.

1 Bigda J.

1 Kamysz E.

1 Koszałka P.

1 Okrój M.

1 Wejda M.

1 Łukasiak J.

Search results

Novel properties of antimicrobial peptides.

Antitumor activity of antimicrobial peptides against U937 histiocytic cell line