Cholest-3,5-dien-7-one formation in peroxidized human plasma as an indicator of lipoprotein cholesterol peroxidation potential

Lipid peroxidation in the peritoneal fluid of infertile women with peritoneal endometriosis

OBJECTIVE

To assess the level of lipid peroxidation in the peritoneal fluid of infertile women with peritoneal endometriosis and of fertile disease-free controls.

STUDY DESIGN

Level of lipid peroxidation (malondialdeyde, malondialdeyde with copper addition, and cholest-3,5-dien-7-one) was measured in the peritoneal fluid obtained from 21 women with endometriosis-related infertility and from 21 fertile women having tubal ligation.

RESULTS

: The level of lipid peroxidation did not differ significantly (P > 0.05) according to the stage of endometriosis. The level of lipid peroxidation (malondialdeyde, malondialdeyde with the addition of copper, and cholest-3,5-dien-7-one) did not differ significantly (P > 0.05) between patients with endometriosis-related infertility (0.07 nmol/ml, 0.34 nmol/ml, 0.24 microg/ml, respectively) and disease-free controls (0.04 nmol/ml, 0.21 nmol/ml, 0.25 microg/ml, respectively).

CONCLUSION

The level of lipid peroxidation did not differ between women with endometriosis-related infertility and fertile disease-free controls, suggesting that increased reactive oxygen species may not be one of the factors responsible for compromised fertility in patients with endometriosis.

Exercised-induced increase in lipid peroxidation parameters in amenorrheic female athletes

OBJECTIVE

To determine plasma lipid peroxidation parameters in eumenorrheic and amenorrheic athletes and to evaluate differences in their response to exercise-induced oxidative stress. In female athletes, intense physical exercise has been shown to be associated with an increased occurrence of menstrual dysfunction with lower levels of E2. Recently, a protective role has been demonstrated for estrogens as free radical scavengers.

DESIGN

Comparison of eumenorrheic and amenorrheic athletes before and after an acute bout of exercise.

SETTING

Academic Research Environment.

PATIENT(S)

Seven eumenorrheic (normally menstruating) and seven amenorrheic (<3 menses/year) female athletes aged 18 to 35 years participating in regular training.

MAIN OUTCOME MEASURE(S)

Plasma and low-density lipoprotein oxidation parameters, plasma E2 and vitamin E levels, and creatine kinase activity.

RESULT(S)

Both the amenorrheic and eumenorrheic athletes demonstrated a significant decrease in the lag time of conjugated diene formation after exercise (P < 0.01), with greater magnitude of change occurring in the amenorrheic athletes (P < 0.05). In addition, postexercise samples from amenorrheic (but not eumenorrhic) athletes showed a significant (P < 0.01) increase in oxysterol formation as compared to baseline values. Amenorrheic athletes also demonstrated a significantly higher baseline creatine kinase activity and a nonsignificant (P = 0.04) trend of an increase in creatine kinase activity after exercise.

CONCLUSION(S)

The results of this study shows that amenorrheic female athletes demonstrate an increased potential for lipid peroxidation after exercise. This could be related to lower plasma E2 levels in this group, considering the strong free radical scavenging ability of estrogens identified recently.

Review of progress in sterol oxidations: 1987-1995

Material dealing with the chemistry, biochemistry, and biological activities of oxysterols is reviewed for the period 1987-1995. Particular attention is paid to the presence of oxysterols in tissues and foods and to their physiological relevance.