title: Time course of hydrogen peroxide induced changes in the lipid peroxidation of human sperm membranes.
abstract: The present study evaluates the changes in sperm motility due to H202 induced membrane damage. Washed human sperm suspended in HAM's F-10  (20-30 x 10 6/ml) were incubated (37 degrees Celsius) with varying concentrations (0-0.05%) of H202 for up to 15 minutes. Sperm were analyzed for % motility, % viability, the ratio of cholesterol to phospholipids (C/PL), and the degree of lipid peroxidation (LPO). Motility was monitored manually and viability was evaluated by the Eosin Y staining method. Total lipids were extracted with chloroform:methanol (1:2) and used in colorimetric determination of cholesterol and phospholipid contents (mcmol/106 sperm). Lipid peroxidation was measured by the production of malondialdehyde (nmol MDA/108 sperm). The results (mean +or- SEM, n=8) indicate a dose a time-dependent effect on % motility during the 15 minute incubation period. In comparison to control (8 +or- 4%), samples incubated with 0.01% H202 exhibited a 25 +or- 3% decrease in % motility, while a complete loss of motility was observed with 0.05% H202. No significant differences in decrease in sperm viability were observed between control (211 +or- 4) and H202 (0.01%) treated samples (14 +or- 2%). An increase of (54 +or- 5%) in lipid peroxidation was observed with 0.01% H202, as compared with an 18 +or- 1% increase in control samples at 15 minutes. The C/PL ratio increased by 46 +or- 4% at 15 minutes in H202 treated samples while showing a 34.3% decrease in control samples. H202 inhibited sperm motility while increasing membrane LPO and C/PL, without altering sperm viability. It would appear that lipid peroxidation and alteration of sperm membrane composition lead to the loss of sperm motility.
authors.forename: M
authors.initials: M
authors.lastname: Bell
authors.forename: S
authors.initials: S
authors.lastname: Sikka
authors.forename: M
authors.initials: M
authors.lastname: Rajasekaran
authors.forename: W
authors.initials: W
authors.lastname: Hellstrom
mesh_terms: D001695:Biology; D019411:Clinical Laboratory Techniques; D003710:Demography; D003933:Diagnosis; D005835:Genitalia; D005854:Germ Cells; D010827:Physiology; D011153:Population; D011157:Population Dynamics; D012098:Reproduction; D012106:Research; D012107:Research Design; D013083:Sperm Transport; D013094:Spermatozoa; D013997:Time Factors; D014566:Urogenital System
keywords: Biology; Demographic Factors; Examinations And Diagnoses; Genitalia; Germ Cells; Laboratory Examinations And Diagnoses; Measurement; Physiology; Population; Population Dynamics; Reproduction; Research Methodology; Sperm Transport--changes; Spermatozoa; Time Factors; Urogenital System