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A kinetics study of pig erythrocyte hemolysis induced by polyene antibiotics
Agnieszka Knopik-Skrocka1, Józef Bielawski, Marta Głab
1Department of Cytology and Histology, A. Mickiewicz University, Fredry 10, 61-701 Poznań, Poland. askro@amo.edu.pl
Abstract:
The kinetics of the hemolysis induced by filipin is of the damage type, indicating the formation of large nonselective perforations of erythrocyte membranes. The process is relatively independent of the ionic composition of the incubation medium, and the differences between the hemolysis induced by filipin in pig and human erythrocytes are not significant. In a sucrose medium, filipin-induced hemolysis is inhibited in humans, whereas it is stimulated in pig erythrocytes. It is suggested that low ionic strength is the reason for the different modifications of complexation of filipin in pig and human erythrocyte membranes in a sucrose medium. The kinetics of the hemolysis induced in pig erythrocytes by amphotericin B and nystatin is of the permeability type, indicating the formation of selective channels in erythrocyte membranes and colloid osmotic hemolysis. The rate of the hemolysis, which is high in a KCl medium, is decreased in all the other media tested (CaCl2, MgCl2, potassium phosphate buffer, K2SO4, sucrose), although there are no changes in the kinetics of hemolysis. The results are interpreted as the formation of highly selective channels at a low concentration of the antibiotics. At increasing concentrations, channels of decreasing selectivity occur. The resistances of pig erythrocytes to amphotericin B and nystatin are lower than those of human erythrocytes.
Insights
Filipin causes large erythrocyte membrane perforations, while amphotericin B and nystatin form selective channels. Ionic strength affects filipin-induced hemolysis differently in pig and human red blood cells.
Area of Science:
- Biochemistry
- Cell Biology
- Membrane Biophysics
Background:
- Erythrocyte membranes are susceptible to damage by various agents.
- Polyene antibiotics like amphotericin B and nystatin, and the polyene macrolide filipin, interact with cell membranes.
- Understanding the mechanisms of membrane damage and permeability changes is crucial for pharmacology and toxicology.
Purpose of the Study:
- To investigate the kinetics and mechanisms of hemolysis induced by filipin, amphotericin B, and nystatin in pig and human erythrocytes.
- To elucidate the role of ionic composition and concentration of agents on hemolysis.
- To compare the susceptibility of pig and human erythrocytes to these agents.
Main Methods:
- Kinetics studies of hemolysis.
- Incubation of erythrocytes in various ionic media (KCl, CaCl2, MgCl2, potassium phosphate buffer, K2SO4, sucrose).
- Comparative analysis of hemolysis in pig and human erythrocytes.
Main Results:
- Filipin induces damage-type hemolysis via large, nonselective membrane perforations, largely independent of ionic strength.
- Filipin-induced hemolysis is inhibited in human erythrocytes but stimulated in pig erythrocytes in sucrose medium.
- Amphotericin B and nystatin induce permeability-type hemolysis, forming selective channels that become less selective at higher concentrations.
- Hemolysis rate by amphotericin B and nystatin is high in KCl but reduced in other media, with pig erythrocytes showing lower resistance than human erythrocytes.
Conclusions:
- Filipin's mechanism involves membrane damage, with differential effects based on species and ionic environment.
- Amphotericin B and nystatin form concentration-dependent selective channels, leading to colloid osmotic hemolysis.
- Pig erythrocytes exhibit lower resistance to amphotericin B and nystatin compared to human erythrocytes, suggesting species-specific membrane interactions.