Pre-eclampsia associated with increased lipid peroxidation and decreased serum vitamin E levels.

OBJECTIVE: To evaluate lipid peroxidation and the serum levels of the antioxidant vitamin E in pre-eclampsia according to the disease severity. METHOD: Serum malondialdehyde (MDA) and vitamin E levels were measured in 18 pre-eclamptic, 15 eclamptic and 25 normotensive pregnant women in Ondokuz Mayis University Hospital. The correlation of these levels with the factors indicating disease severity was tested. Mann-Whitney U-test and correlation coefficients were used for the statistical analysis. RESULT: Both the pre-eclamptic and the eclamptic patients had higher MDA and lower vitamin E levels compared with control (P < 0.05); but these values were not significantly different from each other (P > 0.05). MDA levels were significantly correlated with the systolic and diastolic blood pressure (BP) and with serum uric acid levels. There was significant but negative correlation with the vitamin E levels. CONCLUSION: There is an imbalance between lipid peroxidation and serum vitamin E levels in pre-eclampsia and eclampsia. Increased lipid peroxidation is well correlated with the increase in systolic and diastolic BP measurements and serum uric acid levels.     

Total free radical trapping antioxidant potential in pre-eclampsia.

OBJECTIVE: The aim of the present study was to measure serum urate, tocopherol and ascorbate and to calculate total radical trapping antioxidant potential (TRAP) in pre-eclampsia. METHODS: Study samples were taken from 25 pre-eclamptic, 25 normotensive pregnant and 25 non-pregnant healthy females for measuring uric acid, vitamin C and E, total sulfhydryl group. Also lipid peroxidation product malonaldehyde (MDA), the superoxide generation (NBT reduction) were estimated and TRAP was calculated. Data were analyzed statistically using Student's t-test. RESULT: Pre-eclamptic women had significantly increased MDA levels, superoxide generation and uric acid levels as compared to control subjects (P<0.001). Vitamin C and E and total thiols were lower in pre-eclampsia as compared to control subjects (P<0.001). TRAP was significantly higher in pre-eclampsia. CONCLUSION: TRAP provides a means of assessing the total capacity of the chain-breaking antioxidants to prevent lipid peroxidation in plasma.     

Vitamin E and C in preeclampsia

Vascular endothelial damage has been implicated in the pathophysiology of preeclampsia. Lipid peroxidation may be involved in the process and essential nutrients that can scavenge free radicals, such as vitamin E and C, operate in concert. Antioxidant vitamins E and C were estimated in 30 preeclamptic and 30 normotensive pregnant women. Significantly lowered levels of vitamins E and C were observed in preeclamptic women as compared to controls (P<0.001 and P<0.05 respectively). In patients with preeclampsia antioxidant nutrients may be utilized to a greater extent to counteract free radical-mediated cell disturbances, resulting in a reduction in serum antioxidant levels.     

Role of lipid peroxidation and enzymatic antioxidants in pregnancy-induced hypertension

AIMS AND OBJECTIVES: Preeclampsia remains a major cause of maternal mortality and morbidity. It is a leading indication for iatrogenic premature delivery. Oxidative stress is considered to be one of the factors in the disease process. The present study is centered on the concept that elevated levels of lipid peroxidation (malondialdehyde) due to a decline in the efficacy of antioxidant defenses may predispose an individual to preeclampsia. MATERIAL AND METHODS: In the present study we measured lipid peroxidation products (MDA) and the counteracting enzymatic antioxidants. The study comprises 25 healthy non-pregnant women as controls, 25 third trimester normal pregnant women and 25 preeclamptic patients of the same trimester. Estimation of lipid peroxidation by thiobarbituric acid (TBARS) and enzymatic antioxidants were carried out by standard methods. RESULTS: In the preeclamptic group malondialdehyde, a product of lipid peroxidation, was significantly increased while enzymatic antioxidants like superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase were reduced significantly as compared to normal pregnant and non-pregnant controls. CONCLUSION: Increased levels of lipid peroxides and reduced antioxidant activities clearly demonstrate the presence of oxidative stress in preeclampsia.     

Lipid peroxidation and antioxidants in preeclampsia

OBJECTIVE: To determine the changes in plasma levels of lipid peroxide, vitamin E and vitamin C in women with preeclampsia and to investigate their relationship with diastolic blood pressure. STUDY DESIGN: Cross sectional study consisting of 22 preeclamptic and 21 healthy pregnant women. Fasting venous blood samples were collected during the antepartum period and plasma levels of malondialdehyde, alpha-tocopherol and ascorbic acid were measured. RESULTS: In the preeclamptic group malondialdehyde, a lipid peroxidation product, was significantly increased, while vitamins E and C were significantly decreased compared to healthy pregnant women. A strong correlation was detected between malondialdehyde and antioxidant factors (vitamins E and C) with blood pressure. CONCLUSION: Our findings are consistent with previous studies suggesting that lipid peroxidation is an important factor in the pathogenesis of preeclampsia. In preeclampsia, antioxidant nutrients are excessively utilised to counteract the cellular changes mediated by free radicals.     

Atherogenic profile in preeclampsia

Atherosis is accepted to underlie the pathogenesis of preeclampsia, therefore we aimed to determine malonyldialdehyde (MDA) levels as a marker of lipid peroxidation, and lipoprotein(a) (Lp(a)), apolipoprotein A-1 (Apo A-1) and apolipoprotein B (Apo B) levels as a marker of atherogenic profile in preeclamptic and normal pregnant women. Twenty preeclamptic and 20 gestational-age matched normal pregnant patients were enrolled in the study, mean gestational ages for the preeclamptic and the control group were 33.9+/-1.4 and 35.5+/-0.7 weeks, respectively. Blood was withdrawn from the patients soon after diagnosis, and from the controls at their routine prenatal visits. MDA levels was significantly higher in preeclamptic patients (P=0.0003), but no difference was observed in Apo A-1 and Apo B and Lp(a) levels between the 2 groups. We consider that higher MDA was due to oxidative stress seen in preeclampsia, and similar Apo A-1 and Apo B and Lp(a) levels were due to lack of systemic atherosis.     

Potential atherogenic roles of lipids, lipoprotein(a) and lipid peroxidation in preeclampsia.

AIMS: To evaluate changes in lipid profile, serum levels of malondialdehyde (MDA) and lipoprotein(a) (Lp(a)) and placental MDA in preeclamptic women, and to evaluate the atherogenic role of these changes in the pathophysiology of pre-eclampsia. METHOD: A cross-sectional study was performed in 20 normal pregnant women, 25 women with mild preeclampsia and 28 women with severe preeclampsia in the third trimester. MDA, which is the endproduct of lipid peroxidation, was measured in placental tissue by the thiobarbituric acid (TBA) method of Ohkawa and colleagues and in serum by the TBA method of Asakawa and Matsushita. Serum lipid levels were measured by with an autoanalyzer, serum apolipoprotein (Apo) A-I and Apo B were measured by nephelometric assay and serum Lp(a) level using a nephelometric agglutination assay method. In preeclamptic and normal pregnant women, multiple comparisons between groups were performed by one-way analysis of variance supplemented with Tukey's HSD post hoc test. The association between placental and serum concentrations among groups was analyzed using the Pearson correlation test. RESULTS: Serum levels of MDA, Lp(a), total cholesterol, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and placental MDA were significantly higher, and high-density lipoprotein cholesterol (HDL-C) and Apo A-I levels were significantly lower, in severely preeclamptic and mildly preeclamptic women than in the normal pregnant women, but no difference was observed in Apo B among groups. Serum level of Lp(a) was positively correlated with body mass index in severely preeclamptic women (r=0.489, p=0.008). A significant positive correlation was also found between serum level of MDA and systolic blood pressure in women with severe preeclampsia (r=0.375, p=0.049). CONCLUSIONS: Our findings suggest that high Lp(a), lipid peroxidation, LDL-C and TG, and low HDL-C and Apo A-I levels, are important risk factors for atherosclerosis among preeclamptic women.     

The evaluation of lipid peroxidation products and antioxidative enzymes activity in cord blood and placental homogenates of pregnant diabetic women]

The aim of our study was to estimate the concentration of lipid peroxidation products and antioxidant system activity in cord blood and placental homogenates of 13 pregnant women with type I diabetes, 15 patients with gestational diabetes and 16 healthy pregnant women. Malondialdehyde (MDA) concentration, glutathione (GSH) content and the activity of CuZn superoxide dismutase (SOD) (Bioxytech, Oxis International S. A.) were measured. MDA and GSH levels increased significantly, whereas SOD activity was markedly diminished in diabetics, especially in these with type I, in comparison with the control group. Our results support the hypothesis that diabetic pregnant women and their fetuses/neonates are exposed to an increased oxidative stress. Moreover, we suggest that the measurement of oxidative stress level may be useful in clinical practice to assess fetus/neonate state and the risk of possible complications.     

Altered thiol status in preeclampsia

Thirty preeclamptic, 30 normotensive pregnant and 25 healthy nonpregnant women were analyzed with regard to the antioxidant system (thiols and superoxide dismutase, SOD). In preeclampsia both plasma and lysate thiol levels were significantly lower compared to controls (p < 0.001). SOD levels were higher in normotensive pregnant women, but were lower in preeclamptic compared to nonpregnant women. This finding of antioxidant changes in the red blood cell suggests that red cell dysfunction is fundamental in the development of preeclampsia, and similar alterations in the balance of the thiol could be present across the endothelial cell membrane.     

Significance of changes in lipid peroxides and antioxidant enzyme activities in pregnant women with preeclampsia and eclampsia

This review addresses the general hypothesis that the pathogenesis of preeclampsia and eclampsia are related to an imbalance of increased oxidative stress and lipid peroxidation coupled with a deficiency of antioxidant protection. Accordingly, this study was initiated to assess total antioxidant status and free-radical activity in preeclampsia and eclampsia. The patients studied were 44 healthy pregnant women and 45 women with hypertension classified as having preeclampsia (n=27), and eclampsia (n=18). The serum levels of lipid peroxide were significantly increased (p<0.0001) and antioxidant enzyme activities (superoxide dismutase and glutathione levels) in erythrocytes were significantly decreased (p<0.0001) in women with preeclampsia and eclampsia compared with the controls. The groups of preeclampsia and eclampsia had similar values of catalase activities as the controls (p>0.05). There were no correlations between serum levels of lipid peroxide and antioxidant enzyme activities or systolic-diastolic blood pressure of pregnant women with preeclampsia and eclampsia. The mean systolic and diastolic blood pressure, the serum lactate dehydrogenase (LDH) and aspartate transaminase (AST) levels of preeclamptic and eclamptic women were high, whereas haemoglobin (Hb), Hematocrit (Htc) and platelet levels were lower than those of the control subjects (p<0.0001). There were no differences in mean gestational week, whereas the mean age of eclamptic women was lower than that of the other two groups (p<0.001). The serum levels of Alanine-transaminase (ALT) and urea in eclamptic women were significantly higher compared with the other two groups (p<0.0001), whereas creatinine levels were lower than those of the other two groups (p<0.05). Our findings give support to those few studies considering lipid peroxidation as an important factor in the pathogenesis of preeclampsia and eclampsia. Further studies are needed to clarify the relations between lipid peroxidation and antioxidative function and their pathophysiological significance in preeclampsia and eclampsia.     

Association of Maternal Serum CRP,IL-6, TNF-α, Homocysteine,Folic Acid and Vitamin B12 Levels with the Severity of Preeclampsia and Fetal Birth Weight

Objective: To assess the levels and clinical significance of high sensitive(hs)-CRP (C‐reactive protein), IL-6(interleukin-6), TNF-α(tumor necrosis factor-α), homocysteine, folic acid and vitamin B12 in normotensive healthy pregnant women, mild and severe preeclamptic patients, and to evaluate the correlations between these markers and the severity of preeclampsia and fetal birth weight. Study design: Using a cross-sectional study design, hs-CRP, IL-6, TNF-α, homocysteine and vitamin B12 were measured in the third trimester of pregnancy from normotensive healthy women with uncomplicated pregnancies (n = 62), mild (n = 61) and severe (n = 60) preeclamptic patients. Results: There were statistically significant differences between three groups for hs-CRP (p = 0.012), TNF- α (p = 0.046), IL-6 (p = 0.015), homocysteine (p < 0.001) and fetal birth weight (p < 0.001). Fetal birth weights in mild (2477 ± 746) and severe (2435 ± 768) preeclamptic patients were significantly lower than controls (3485 ± 365) (p < 0.001). No significant difference was found between the three groups for folic acid (p = 0.066) and vitamin B12 (p = 0.286). Bonferroni adjusted multiple comparison test showed that the statistical differences with respect to TNF-α, IL-6 and homocysteine were mainly created by control and severe preeclampsia groups. Hs-CRP levels still remained higher in severe preeclampsia patients than mild preeclampsia and normotensive patients except for overweight patients in the previous two groups after Bonferroni post hoc adjustment test. Conclusion: Elevated maternal serum levels of hs-CRP, TNF- α, IL-6 and homocysteine in preeclamptic women correlate with fetal birth weight in the early third trimester.     

Lipid and protein oxidation and antioxidant function in women with mild and severe preeclampsia

OBJECT: The aim of this study was to evaluate the lipid and protein oxidation and antioxidant function in preeclampsia patients and in normotensive pregnant women, as well as, to assess an association with the severity of the disease. METHOD: The study was carried out in 30 patients with mild preeclampsia, 30 with severe preeclampsia, and in 50 normotensive pregnant women during the third trimester of pregnancy. Lipid peroxides in serum, placental and decidual tissues and serum protein carbonyls and some of the antioxidants were measured by spectrophotometric methods. One-way analysis of variance, chi-square test and Pearson correlation test were used for the statistical analyses. Logistic regression procedures were used to calculate odds ratios (OR). RESULTS: Lipid peroxides in serum, placenta and decidua basalis and protein carbonyls in serum were significantly increased, and vitamin E and total carotene levels in serum were significantly decreased especially in women with severe preeclampsia compared with mild preeclampsia and controls. A significant correlation was detected between diastolic blood pressure and lipid peroxides in serum, placental and decidual tissues and serum protein carbonyls. Furthermore, there was significant correlation between antioxidant vitamins and lipid and protein oxidation products in severe preeclamptic patients. Also, logistic regression analysis showed that changes in serum, placental and decidual lipid peroxides and serum protein carbonyls, vitamin E and total carotene concentrations were significantly associated with preeclampsia. CONCLUSION: Our findings suggest that lipid and protein oxidation may be an important factor in the pathogenesis of preeclampsia. Since antioxidant vitamins are significantly decreased in both severe and mild preeclamptic pregnants, early supplementation with antioxidants may be beneficial in preeclamptic patients.     

Lipid peroxidation, antioxidant defense, status of trace metals and leptin levels in preeclampsia

OBJECTIVE: To investigate the changes in enzyme activities of erythrocyte superoxide dismutase (SOD), catalase, and placental glutathione peroxidase (GSH-Px), and analyze the levels of serum malondialdehyde (MDA), copper (Cu), zinc (Zn), selenium (Se), leptin and placental MDA and glutathione (GSH). STUDY DESIGN: Cross-sectional prospective study consisting of 32 preeclamptic (PE) pregnant, 25 non-pregnant (NP) women, 28 healthy pregnant (HP) women. Levels of lipid peroxides in serum and placenta, and activities of SOD, catalase in erythrocyte and placental GSH level, placental GSH-Px activity were measured by spectrophotometric methods. Serum levels of Cu, Zn, Se measured by atomic absorption spectrophotometry. Serum levels of leptin was measured by enzyme immunoassay by using the Cayman chemical kit. One-way analysis of variance and post hoc Tukey-HSD test and Pearson correlation test were used for the statistical analyses. RESULTS: Serum levels of MDA, Cu, Leptin were markedly higher (P < 0.001); and serum level of Se was markedly lower (P < 0.001) in PE women compared with HP women and NP women. Also, placental MDA level was higher (P < 0.001) and placental GSH-Px activity was lower in PE women compared with HP women. In preeclamptic women erythrocyte catalase activity was markedly increased (P < 0.001), while erythrocyte SOD activity was markedly decreased (P < 0.001) compared to HP women and NP women. Placental GSH level was decreased compared to HP women (P < 0.001). Serum level of Zn was markedly decreased compared to NP women (P < 0.001) but no significant difference was observed in PE pregnant when compared with HP women (P > 0.05). Placental MDA level in PE women had significant negative correlation with serum Se level (r = -0.353, P < 0.05). A negative correlation was found between erythrocyte catalase activity with birth weight (r = -0.528, P < 0.001). Also, there were a significant negative correlation between serum levels of Cu and Se in the preeclamptic women (r = -0.407, P < 0.05). CONCLUSION: Our data demonstrate that elevation of lipid peroxides together with impaired antioxidant defense mechanisms and status of trace metals and the presence of possible interrelationship and crosstalk between those parameters may be related at least partly to the pathogenesis of preeclampsia. Additionally, lipid peroxides and blood oxidative imbalance could be part of the cytotoxic mechanisms leading to endothelial cell injury.     

CONCENTRATIONS OF APOLIPOPROTEINS E,C2 AND C3 AND LIPID PROFILE IN PREECLAMPSIA

Objective: Preeclampsia is associated with an abnormal lipid profile and high apolipoprotein E (Apo E) levels. Apo E may favor lipid uptake by macrophages and is thought to increase triglycerides clearance. However, high Apo E levels may interfere with lipolysis by interacting with the lipoprotein lipase (LPL) activator, apolipoprotein C₂ (Apo C₂). LPL activity may also be impaired by high levels of the LPL inhibitor apolipoprotein C₃ (Apo C₃). Therefore, lipid profile depends on the balance between the opposing effects of Apo C₂ and Apo C₃ and on interference due to Apo E. We investigated the involvement of these three lipoproteins in lipid disorders associated with preeclampsia. Methods: Blood samples were taken from 25 normotensive and 24 preeclamptic pregnant women after a 12-hr fasting period. These samples were analyzed for standard lipid profile and Apo E, C₂, C₃ concentrations. Results: Concentrations of triglycerides, total cholesterol, LDL, HDL, and LDL cholesterol did not differ significantly between preeclamptic women and pregnant controls. Apo C₂ concentration and Apo E/Apo C₂ ratio did not differ between the two groups of women but Apo C₃ and Apo E concentrations were higher in preeclamptic than in pregnant controls. The ratio of triglycerides to Apo E was similar in the two groups of women. In both groups, triglycerides levels were positively correlated with Apo E (p=0.0429), Apo C₂ (p=0.0045) and Apo C₃ (p=0.0004) concentrations, but not with Apo E/Apo C₂ ratio (p=0.760). Conclusions: In preeclamptic women, the increase in Apo E concentration may not increase triglycerides clearance because LPL activity seems to be inhibited by high Apo C₃ concentration.     

SERUM ANTIBODIES TO OXIDIZED LOW-DENSITY LIPOPROTEIN IN PREGNANT WOMEN WITH PREECLAMPSIA AND CHRONIC HYPERTENSION: LACK OF CORRELATION WITH LIPID PEROXIDES

Objectives: To evaluate the circulating levels of antibodies to oxidized low-density lipoprotein (LDL) and their correlation with the lipid peroxide/vitamin E ratio in pregnant women with preeclampsia and chronic hypertension.

Methods: Antibodies to oxidized LDL were measured by enzyme-linked immunoassay, lipid peroxides (malondialdehyde), and vitamin E were measured by high-pressure liquid chromatography. Patients were 25 healthy pregnant women, 20 previously nonhypertensive women diagnosed with preeclampsia, and 20 women with uncomplicated chronic hypertension.

Results: Serum levels of antibodies to LDL in preeclamptic patients were similar to controls, whereas women with chronic hypertension showed a trend for increased mean levels. Lipid peroxides in serum were significantly increased and vitamin E levels were significantly decreased in preeclampsia with respect to nonhypertensive pregnancy, but no differences were observed for chronic hypertensive women.

Conclusions: Our results suggest that preeclampsia is not accompanied by increased levels of antibodies to oxidized LDL. By contrast, and according to previous studies in nonpregnant patients, chronic hypertensive patients showed a trend for elevated levels.     

Elevated amniotic fluid leptin levels in pregnant women who are destined to develop preeclampsia

OBJECTIVE: To analyze whether leptin levels of the amniotic fluid elevate during early pregnancy in women destined to develop preeclampsia and to evaluate the relationship between amniotic fluid leptin levels and gestational age, maternal body mass index, and fetal sex. STUDY DESIGN: Leptin levels of the amniotic fluid were compared in two groups of women, preeclamptic (n = 20) and normotensive pregnant (n = 40), matched for fetal sex, maternal body mass index at sampling, gravidity and fetal gestational age at sampling. Furthermore, amniotic leptin levels in 400 normotensive pregnant women were analyzed for their correlation with gestational age, maternal body mass index, and fetal sex. RESULTS: Median leptin concentrations were significantly higher (p < 0.001) in the women with preeclampsia (7.3+/-0.7 ng/ml) than in the normotensive pregnant women (4.1 +/- 0.3 ng/ml), independent of fetal sex. The leptin levels in the amniotic fluid decreased with advanced gestational age (r = 0.24, p < 0.001). Amniotic fluid leptin levels in the pregnant women carrying a female fetus (5.6+/-0.3ng/ml) were significantly higher than those carrying a male fetus (4.7+/-0.2 ng/ml) (p = 0.004). CONCLUSION: Higher amniotic fluid leptin levels were observed in the preeclamptic pregnant women, and they decreased as gestational age advanced. Furthermore, the women with a female fetus were noted to have higher amniotic fluid leptin levels.     

Evaluation of the macula,retinal nerve fiber layer and choroid in preeclampsia,healthy pregnant and healthy non-pregnant women using spectral-domain optical coherence tomography

Objective: To evaluate the macular, retinal nerve fiber layer (RNFL) and choroidal thickness alterations by using spectral-domain optical coherence tomography (SD-OCT) in preeclampsia and compare with healthy pregnant and healthy non-pregnant controls. Method: The study population included healthy pregnant control group (n: 25), healthy non-pregnant control group (n: 26) and study group with preeclampsia (n: 27). Retinal thickness parameters were measured by SD-OCT. Results: There was a statistically significant difference among all of the groups for choroidal thickness (p?p?p?p?=?0.004). Conclusions: This study revealed that choroidal thickness measured using SD-OCT increased in women with preeclampsia and healthy pregnant women but the increase in choroidal thickness in preeclampsia was lower than the healthy pregnant controls. This lower rise in choroidal thickness can be generally attributed to the markedly increased systemic vascular vasospasm secondary to preeclampsia.     

Oxidative stress in pre-eclampsia

BACKGROUND: The objective of this study was to test the hypothesis that maternal plasma, cord plasma and placental tissue lipid peroxidation products are increased and antioxidants are decreased in women with pre-eclampsia. METHODS: Placenta, maternal and cord plasma were collected at delivery from 29 normal, 21 pre-eclamptic and six eclamptic women. Plasma was collected from 21 non-pregnant matched controls. The analyses were measured by HPLC and colorimetric assay. RESULTS: Plasma maternal concentrations of uric acid, LPO, MDA, ascorbic acid, vitamin E and cholesterol were not significantly different in pre-eclampsia as compared with normal pregnancy. Plasma concentrations of ascorbic acid and vitamin E were not significantly different in normal pregnancy as compared with the non-pregnant controls. Cord plasma concentrations of MDA were significantly higher in eclampsia (1.16+/-0.26 micromol/l) as compared with normal pregnancy (0.79+/-0.05 micromol/l, p<0.02) and pre-eclampsia (0.83+/-0.05 micromol/l, p<0.05). Cord plasma concentrations of vitamin E were significantly higher in eclampsia (21.3+/-7.5 micromol/l) as compared with normal pregnancy (10.2+/-1.1 micromol/l, p<0.01) and pre-eclampsia (10.4+/-1.8 micromol/l, p<0.04). Placental concentrations of LPO, MDA and ascorbic acid were not significantly different in pre-eclampsia as compared with normal pregnancy. Plasma cord concentrations of LPO and placental concentrations of vitamin E were undetected for normal pregnant, pre-eclamptic and eclamptic women respectively. Uric acid concentrations were significantly increased in eclampsia as compared with the non-pregnant controls (p<0.0001), normal pregnant controls (p<0.0001) and pre-eclampsia (p<0.008). CONCLUSIONS: The findings in this study do not show any evidence of deficiency in the maternal protective antioxidant systems or increased production of lipid peroxidation products, LPO and MDA in African women with pre-eclampsia as compared with normal pregnancy. However, there was evidence of increased cord plasma concentrations of MDA and vitamin E in eclampsia as compared with normal pregnancy and pre-eclampsia. The placenta may be effective in removing MDA. The antioxidant uric acid serves as a protective role whilst the antioxidant and oxidant capacity in the different study groups remained unchanged.     

Low plasma levels of oxidized low density lipoprotein in preeclampsia

BACKGROUND: Markers of lipid peroxidation are commonly used to assess oxidative stress in preeclampsia. The aim of this study was to assess the concentration of oxidized low density lipoprotein (oxLDL), a novel marker for lipid peroxidation, and that of the thiobarbituric acid reactive substances (TBARS) in the pathogenesis of severe preeclampsia and to investigate the influence of gestational age on these parameters. METHOD: Plasma levels of oxLDL and TBARS were assayed in women with severe preeclampsia (n = 40), normotensive pregnant controls matched for gestational age (n = 24) and normotensive pregnant controls at full term (n = 16). RESULTS: Women with preeclampsia showed lower oxLDL levels (mean +/- SE) than matched controls (181 +/- 12 vs. 219 +/- 14; p = 0.027), whereas no differences were found for the TBARS concentration (3.8 +/- 0.6 vs. 3.7 +/- 0.4). When women with preeclampsia were compared to control women at full term, TBARS were elevated (3.8 +/- 0.6 vs. 1.5 +/- 0.2; p = 0.01). However, in women with normotensive pregnancy TBARS were also lower in full-term control pregnancy compared to early third-trimester values (p < 0.0001). CONCLUSION: Plasma TBARS decreased during the third trimester of pregnancy, underlining the importance of matching for gestational age when studying markers of lipid peroxidation in pregnant women. Women with preeclampsia had lower plasma levels of oxLDL compared to gestational age-matched controls, indicating that oxLDL could be a marker for preeclampsia.     

Levels of stable metabolites of prostacyclin and thromboxane A2 and their ratio in normotensive and preeclamptic pregnant women during the antepartum and postpartum periods

OBJECTIVE: To measure the levels of the circulating metabolites of prostacyclin and thromboxane A2 during the antepartum and postpartum periods in severe preeclamptic and eclamptic patients as well as in normotensive pregnant women. METHODS: 6-Keto-prostaglandin F1alpha (6-keto-PGF1alpha) and thromboxane B2 (TxB2) were measured in the plasma of 15 severe preeclamptic, 15 eclamptic, and 15 normotensive pregnant women during the antepartum and postpartum (5th day) periods. At the same time blood pressure measurements were obtained. Kruskal-Wallis, Wilcoxon rank-sum, and Wilcoxon's signed-rank tests were used for statistical analysis. RESULTS: 1) There was no significant difference in the levels of 6-keto-PGF1alpha and TxB2 of the normotensive pregnant women between the antepartum and the postpartum (5th day) periods. 2) In the severe preeclamptic and eclamptic groups, 6-keto-PGF1alpha levels showed significant increase after the delivery (P < 0.01, and P < 0.001, respectively). 3) In the severe preeclamptic and eclamptic groups TxB2 levels showed significant decrease after delivery (P < 0.01, and P < 0.001, respectively). 4) The 6-keto-PGF1alpha/TxB2 ratio both during the antepartum and the postpartum (5th day) periods showed significant differences between the severe preeclamptic and normotensive, and between the eclamptic and normotensive groups (P < 0.001, and P < 0.001 respectively). 5) No correlation was observed between the mean arterial pressure and the antepartum levels of 6-keto-PGF1alpha TxB2 or their ratios. CONCLUSIONS: Our study was able to demonstrate a significant difference in circulating metabolites of prostacyclin and TxA2 between normotensive pregnant women and those with severe preeclampsia and eclampsia. But no correlation was observed between the blood pressure and the antepartum 6-keto-PGF1alpha, TxB2 levels or their ratios. 6-keto-PGF1alpha levels increased and TxB2 levels decreased in the postpartum period (5th day). However, the 6-keto-PGF1alpha/TxB2 ratio was still low in the severe preeclamptic and eclamptic patients when compared with the control group. This situation shows that the pathophysiologic mechanism does not improve completely within a few days after delivery.