title: Proinflammatory cytokines as an intermediate factor enhancing lipid sperm membrane peroxidation in in vitro conditions.
abstract: 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.
authors.affiliation: Institute of Human Genetics, Polish Academy of Sciences, Strzeszynska 32, 60-479 Poznan, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Fraczek
authors.forename: Dorota
authors.initials: D
authors.lastname: Sanocka
authors.forename: Marzena
authors.initials: M
authors.lastname: Kamieniczna
authors.forename: Maciej
authors.initials: M
authors.lastname: Kurpisz
mesh_terms: 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