Proinflammatory cytokines as an intermediate factor enhancing lipid sperm membrane peroxidation in in vitro conditions.
We have examined the effect of white blood cells (WBCs), various proinflammatory cytokines, or a combination of the two on the peroxidation of human sperm membrane lipids in in vitro conditions. Six recombinant cytokines, such as interleukin-1beta (IL-1beta), IL-6, IL-8, IL-12, IL-18, and tumor necrosis factor alpha (TNF-alpha), used singly or in combinations, were analyzed. WBCs were isolated from the whole heparinized blood using a density gradient technique (Histopaque 1.077). Spermatozoa were isolated from semen samples with normal sperm parameters by both the swim-up technique (swim-up fraction) and by a discontinuous Percoll gradient centrifugation (90% and 47% Percoll fractions). Peroxidative damage to sperm membrane lipids was assessed by determining the concentration of malondialdehyde (MDA) in lysates of spermatozoa using high-performance liquid chromatography (HPLC). There were no statistically significant differences in MDA concentrations between sperm fractions incubated with cytokines and respective controls (spermatozoa alone). In spermatozoa isolated by the swim-up technique, the MDA level was significantly higher only after incubation with IL-6 and IL-8 plus WBCs when compared to sperm incubated with leukocytes alone (0.62 +/- 0.21 micromol/L and 0.42 +/- 0.22 micromol/L, respectively; P < .05). In spermatozoa recovered from the 47% Percoll, only a combination of IL-12 and IL-18 used together with WBCs was linked with a significant increase in MDA concentration (from 0.41 +/- 0.13 micromol/L to 0.65 +/- 0.19 micromol/L; P < .05). The results obtained suggest that cytokines produced during the inflammatory process intensify the level of oxidative stress caused by leukocytes, which may have serious consequences for sperm membrane integrity.
Fraczek
Monika
M
Institute of Human Genetics, Polish Academy of Sciences, Strzeszynska 32, 60-479 Poznan, Poland.
Sanocka
Dorota
D
Kamieniczna
Marzena
M
Kurpisz
Maciej
M
D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007249:Inflammation / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D018664:Interleukin-12 / Q000378:metabolism; D020382:Interleukin-18 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015227:Lipid Peroxidation / Q000276:immunology*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D013094:Spermatozoa / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism