Impairment of human polymorphonuclear leukocyte chemotaxis by 2,5-hexanedione

Abstract

The effect of n-hexane metabolites on human polymorphonuclear leukocyte chemotaxis and luminol-dependent chemiluminescence was investigated. No effect was detected when 2-hexanol, 2-hexanone and gamma-valerolactone were used; 2,5-hexanedione at 75 micrograms/ml inhibited chemotaxis and a direct correlation between increasing the xenobiotic concentration and the degree of inhibition was found. Chemotactic peptide-induced chemiluminescence was not affected by 2,5-hexanedione. In order to clarify the phenomenon, plasma membrane fluidity was investigated by fluorescence polarization of the fluorescent probe trimethylammonium diphenylhexatriene. 2,5-hexanedione increased the membrane fluidity, while the other n-hexane metabolites did not change the degree of fluorescence polarization. Results suggest that the cellular functions modulated by membrane-cytoskeletal organization are affected by 2,5-hexanedione also at the low concentrations.

Prevention of chemically induced changes in synaptosomal membrane order by ganglioside GM1 and α-tocopherol

“…Several neurotoxic compounds have been reported to modulate the microviscosity of membranes including those derived from nervous tissue [38). In general, organic solvents including ethanol and anesthetics decrease order [39,40]. Heavy metal cations tend to increase membrane order [40,41) as does calcium [42,43] Lipid peroxidation has been reported to increase the rigidity of phospholipid bilayers [44) and erythrocyte membranes [33].…”

Activation of the alternative complement pathway and generation of stimulating factors for granulocytes by glass fibers

“…A modified Boyden technique was used. As previously described (Governa et al, 1986), 106 PMN were centrifuged against a 5 #m pore-sized cellulose acetate filter (Millipore Corp., Bedford, MA, USA). The upper compartment of the Boyden chamber was filled with RPMI 1640 after the lower one had been similarly filled with the supernatant of the testing serum diluted 1:10 in RPMI 1640.…”

Increased membrane heterogeneity in stimulated human granulocytes

“…PMN cells were isolated from venous blood of healthy volunteers using Ficoll-Hypaque gradient centrifugation [9]. Cells were washed three times and suspended at a concentration of 106/ml in HBSS supplemented with 5 mM glucose and were labeled with TMA-DPH intensity of the two components did not change significantly upon stimulation.…”