Glomerular endothelial injury associated with free radical production induced by a fungal cell wall component, (1→3) β-D glucan

[摘要] Clinical evidence suggests that microangiopathy may be induced by fungal infection. The present study evaluated the toxic effect of (1-->3) beta-D glucan, a major component of fungal cell wall, on cultured transformed glomerular endothelial cells (TF-GEN). When TF-G;EN were exposed to increasing concentrations of (1-->3) beta-D glucan (beta-DG; 115 to 430 pg/ml) for 1 to 3 hours, concentration-and time-dependent increases in hydroxyl radical production were demonstrated by electron paramagnetic resonance spectrometry using 5, 5-dimethyl-1-pyrrolyne-N-oxide as a spin trap agent. The amount of radicals induced by 230 or 430 pg/ml beta-DG was comparable to that induced by E. coli LPS (1 or 10 mu g/ml). The beta-DG-induced free radical production was associated with a subsequent increase in LDH release from TF-GEN. When TF-GEN pretreated with U78517F (0.1 or 1.0 mu M), a lipophilic antioxidant, were stimulated with LPS (1 or 10 mu g/ml) or beta-DG (230 pg/ml) for 3 hours, free radical production by TF-GEN was significantly reduced in cells pretreated with the higher concentration of U78517F. Thus, fungal (1-->3) beta-D glucan induces glomerular endothelial injury by stimulating cellular free radical production. Such a mechanism may underlie microangiopathy in systemic fungal infections.

[发布日期] 1997-12-12

[关键词] beta-D glucan;free radicals;glomerular endothelial injury;antioxidant;electron paramagnetic resonance