17β-Estradiol Inhibits Lysophosphatidylcholine-Induced Apoptosis in Cultured Vascular Smooth Muscle Cells

Objectives

Coronary heart disease (CHD) risk increases in women after menopause, but menopausal hormone therapy (MHT) helps prevent CHD if started early after menopause. To explore the mechanism underlying the direct vascular actions of estrogen, the effects of 17β-estradiol (E₂) on apoptosis of vascular smooth muscle cells (VSMCs) induced with lysophosphatidylcholine (lysoPC), an active component of oxidized low-density lipoprotein, were investigated in the present study.

Methods

VSMCs were isolated from rat aortas. Apoptosis and protein expression of caspases were assessed using propidium iodide staining and Western blot analysis, respectively. Intracellular formation of reactive oxygen species (ROS) was examined using dichlorofluorescein diacetate, a cell-permeable oxidation-sensitive probe, and quantitated with flow cytometry. Nuclear factor-κB (NF-κB) activation was determined after transfection with a reporter plasmid containing the luciferase reporter gene.

Results

After pre-treatment for 24 hours, 17β-E₂ suppressed lysoPC-induced (15 µM) apoptotic cell death in a dose-dependent manner with statistical significance at near physiological concentration. 17β-E₂ (10⁻⁶ M) also increased protein levels of caspase-9 and -8 precursors and decreased the active form of caspase-3. Western blot analysis using subcellular fractions showed that 17β-E₂ decreased mitochondrial Bax levels and concomitantly increased cytosolic Bax expression. Furthermore, intracellular production of ROS and NF-κB-mediated transcriptional activity were reduced with 17β-E₂. In addition, estrogen effects on apoptosis were partially blocked by ICI 182,780, a specific estrogen receptor antagonist.

Conclusions

In cultured VSMCs treated with lysoPC, 17β-E₂ reduced apoptotic cell death by down-regulating both extrinsic and intrinsic apoptosis pathways, contributing to the preventive action of MHT against CHD.

The Effect of Multidisciplinary Approach on the Birth Rate of Fetuses with Prenatally Diagnosed Congenital Heart Disease

BACKGROUND

This study aimed to determine the effect of a multidisciplinary approach on the birth rate of fetuses with prenatally diagnosed congenital heart diseases (CHDs).

METHODS

Among the fetuses of 724 gravidas who underwent fetal echocardiography in Samsung Medical Center from January 2013 to June 2017, 463 fetuses with normal cardiac structure, arrhythmia or simple left-to-right shunt were excluded, and the remaining 261 were included in the study. The subjects were subdivided into groups based on whether they were consulted multidisciplinarily, that is, consulted simultaneously by pediatric cardiologists, obstetricians and pediatric cardiac surgeons or not. They were also categorized based on the initial fetal echocardiogram results.

RESULTS

Among the fetuses in the multidisciplinary group, 64.5% of the fetuses were given birth to, and the proportion was not different from that in the non-multidisciplinary group (68.6%, P = 0.48). The delivery rate in the multidisciplinary consultation group were 69.2% in the transposition of the great arteries group, 63.6% in the tetralogy of Fallot group, 68.8% in the pulmonary atresia or interrupted aortic arch group, 62.5% in the coarctation of aorta group, 60.0% in the atrioventricular septal defect group, 70.0% in the functional single ventricle group, and 55.6% in the hypoplastic left heart syndrome group; there were no significant differences between the 10 echocardiogram groups. However, when the subjects were categorized into Fontan repair group and biventricular repair group, the Fontan repair group showed a significant increase in the likelihood of delivery when a multidisciplinary approach was taken (P = 0.035).

CONCLUSION

When a fetus was diagnosed with a CHD where Fontan repair should be considered, a multidisciplinary approach resulted in increased possibility of delivery.

Co-transplantation of fetal bone tissue facilitates the development and reconstitution in human B cells in humanized NOD/SCID/IL-2Rγnull (NSG) mice

BACKGROUND

In terms of the function and reconstitution efficacy of human immune cells, co-transplantation of human fetal tissues, such as thymus and liver, with CD34(+) hematopoietic stem cells (HSCs) has potential advantages in the generation of humanized mice.

OBJECTIVE AND METHODS

To examine the effects of bone tissues in the reconstitution of human immune cells, particularly in B cells, we generated a new humanized mice co-transplanted with human fetal thymus (hFT)/fetal bone (hFB) tissues and human fetal liver-derived CD34(+) cells.

RESULTS

Humanized mice exhibited effective reconstitution of human immune cells earlier compared to control humanized mice. In terms of quantity, the number of immune cells, such as human T, B, and monocyte/macrophages was significantly increased. Furthermore, significant increase of B cell progenitors and immature/naïve B cells could be detected in the bone marrow and spleen of humanized mice.

CONCLUSION

Our results demonstrate that co-transplantation of hFB tissue may facilitate the reconstitution of human B and T cells, and therefore the humanized model may be used to develop therapeutic human antibodies for clinical use.

Changes of nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9) in human myometrium before and during term labor

OBJECTIVE

To investigate the changes of nuclear factor kappa B (NF-kappaB), cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9) in human term myometrium before and during term labor.

STUDY DESIGN

Myometrium was obtained from women undergoing cesarean delivery at term before (n=16) and after labor (n=12). Immunostaining of NF-kappaB subunits (p65/p50) and Western blot analysis of NF-kappaB subunits, MMP-9 and COX-2 proteins were compared. Human term myocyte cultures were stimulated with IL-1beta. Activation of NF-kappaB was assessed by evaluating changes in the inhibitory protein IkappaB; regulation of COX-2 and MMP-9 levels was studied using Western blot analysis and gelatin zymography.

RESULTS

In contrast to a significant increase in the level of COX-2 and MMP-9 proteins, p65 and p50 decreased significantly in the after-labor group compared to the before-labor group. After treatment with IL-1beta, IkappaB was degraded by almost 90% within 5 min and became undetectable by 15 min. IL-1beta stimulation increased the levels of COX-2 protein and the gelatinolytic activities of MMP-9, both of which were inhibited by NF-kappaB inhibitors.

CONCLUSIONS

Human term labor is associated with changes in NF-kappaB and increased expression of COX-2 and MMP-9 in the myometrium. NF-kappaB pathway activation and subsequent increments of COX-2 and MMP-9 were observed in human term myocyte cultures.

Expression of CD44 adhesion molecules on human placentae

OBJECTIVE

This study was performed to characterize CD44 expression in human placentae.

STUDY DESIGN

We conducted reverse transcriptase polymerase chain reaction (RT-PCR) analyses of CD44H (hematopoietic form, also called CD44s) and CD44R1 (epithelial form) in 14 normal term placentae, and immunohistochemical analysis of CD44H and CD44v6 in 31 placentae (25 term and 6 first-trimester).

RESULTS

All 14 term placentae expressed CD44H (double bands) suggesting expression of alternative isoforms on the placentae. CD44R1 was expressed on 3 of 14 (21.4%) term placentae. Immunohistochemical analysis revealed expression of CD44H in all the placentae examined. However, positive staining for CD44v6 was observed in 3 of 6 (50%) first-trimester and only 6 of 25 (24%) term placentae showing decreased expression on term placentae. Positive staining for CD44v6 was observed on the trophoblast surface of immature villi especially in the sub-chorionic area where hypoxic conditions prevail.

CONCLUSION

These results suggest that CD44 splicing variants might play a role in the invasion of trophoblast into maternal tissue in early pregnancy.

Multiple courses of antenatal corticosteroid therapy in patients with preterm premature rupture of membranes

OBJECTIVE

This study was performed to determine the benefits and risks of multiple courses of corticosteroids in patients with preterm premature rupture of membranes (PPROM).

METHOD

We retrospectively evaluated the pregnancy and neonatal outcomes of women with singleton pregnancies, who were admitted at 24-32 weeks of gestation due to PPROM. Patients were categorized into 3 groups according to antenatal corticosteoid exposure: (1) a non-user group, (2) a single-course group, and (3) a multiple-course group.

RESULT

A total of 170 patients were included in the study, with 50 in the non-use group, 76 in the single-course group, and 44 in the multiple-course group. Univariate analyses showed that clinical chorioamnionitis occurred with highest incidence in multiple-course group (chi2=6.20, p<0.05) and the incidence of neonatal respiratory distress syndrome (RDS) was lowest in the multiple-course group (chi2=10.0, p<0.01). Multiple logistic regression analyses showed that multiple courses of corticosteroids were independently associated with clinical chorioamnionitis (odds ratio=13.15, p<0.05) whereas no significant association was found between RDS and multiple-course corticosteroids after adjusting for confounding variables (odds ratio=0.28, p=0.06).

CONCLUSION

Multiple courses of antenatal corticosteroid therapy were found to be associated with an increased risk of clinical chorioamnionitis and seemed not to reduce the incidence of RDS and other neonatal morbidities in patients with PPROM.

Transvaginal ultrasonography for cervical assessment before induction of labor

OBJECTIVE

To evaluate the value of ultrasonographic cervical assessment in predicting the outcome of labor induction and to compare its performance against the Bishop score.

METHODS

The Bishop score was determined by digital examination, and transvaginal ultrasonography was performed in 105 women at 37 to 42 weeks' gestation scheduled for labor induction. Ultrasonographic parameters evaluated were cervical length, the presence of funneling, funnel width, and funnel length and were blinded to managing physicians. The primary outcome was the occurrence of active labor within 2 days (successful labor induction). The interval from the onset of induction to active labor (duration of induction) was the secondary outcome. Statistical analysis was performed by the chi2 test, Wilcoxon rank sum test, Pearson correlation, receiver operating characteristic curves, logistic regression, Cox proportional hazards model, and generalized Wilcoxon test for survival data.

RESULTS

Induction of labor was successful in 93 women (89%). The area under the receiver operating characteristic curve for cervical length was greater than that of the Bishop score in predicting a successful labor induction (z = 2.18; P < .05). A cervical length of 3.0 cm or less had sensitivity of 75% (70 of 93) and specificity of 83% (10 of 12). Multiple logistic regression analysis showed a significant relationship between successful labor induction and cervical length but not the Bishop score (odds ratio = 0.24; 95% confidence interval, 0.096-0.59; P = .002). Only parity and cervical length had a significantly independent relationship with the duration of induction.

CONCLUSIONS

Cervical length measured by transvaginal ultrasonography is a useful and independent predictor of successful labor induction and the duration of induction and provides better predictability of successful labor induction than the Bishop score does.

17Beta-estradiol inhibits proliferation of cultured vascular smooth muscle cells induced by lysophosphatidylcholine via a nongenomic antioxidant mechanism

OBJECTIVE

Lysophosphatidylcholine (lysoPC), an active component of oxidized low-density lipoprotein, stimulates proliferation of vascular smooth muscle cells (VSMC). We investigated the direct impact of 17beta-estradiol (E2) on the proliferation of VSMC from rat aorta.

RESULTS

VSMC derived from both female and male rats expressed estrogen receptors alpha and beta. Treatments with 1% fetal bovine serum or 5 microM lysoPC increased the incorporation of [3H]-thymidine in VSMC obtained from female rats. 17Beta-E2 did not alter the response to fetal bovine serum, but significantly suppressed the enhanced deoxyribonucleic acid synthesis which had been induced by lysoPC in a dose-dependent manner (10(-4)-10(-6) M). Estrogen also inhibited the proliferation of VSMC from male animals. ICI 182,780, a specific estrogen receptor antagonist, and 17alpha-E2, an inactive form of estradiol, also decreased the mitogenic response to lysoPC in VSMC. In addition, N-acetyl-L-cysteine, a potent antioxidant, inhibited the lysoPC effect. Flow cytometric analysis using the oxidation-sensitive probe 2',7'-dichlorofluorescin diacetate revealed that elevated intracellular formation of reactive oxygen species elicited with lysoPC was depressed significantly by 17beta-E2, ICI 182,780, or 17alpha-E2 as well as by N-acetyl-L-cysteine.

CONCLUSION

17Beta-E2 inhibits in vitro VSMC proliferation induced by lysoPC via a nongenomic antioxidant mechanism.

Changes in biochemical bone markers during pregnancy and puerperium

To elucidate the changes in bone turnover during pregnancy and puerperium, we measured serially the levels of serum osteocalcin and urine deoxypyridinoline (Dpy) as markers of bone formation and bone resorption, respectively, in 22 healthy women with normal pregnancy. Nineteen non-pregnant women served as control. The Dpy levels increased significantly at 16 weeks of pregnancy and remained elevated thereafter. The levels of osteocalcin, however, were significantly decreased at 16 weeks of pregnancy and elevated later at 6 weeks postpartum. Bone turnover ratio (Dpy/osteocalcin) continued to rise during pregnancy, but returned to control levels 6 weeks after delivery. Dpy levels and bone turnover ratio during puerperium tended to be higher in 17 breast-feeding women than those of 5 exclusive bottle-feeders. In conclusion, bone resorption begins to increase from the second trimester of pregnancy and calcium release from bone tissue might play a major role in calcium homeostasis during the whole period of pregnancy as well as during lactation.

Up-regulation of matrix metalloproteinase-9 in human myometrium during labour: a cytokine-mediated process in uterine smooth muscle cells

The pregnant uterus undergoes dramatic changes of tissue remodelling during the labour and post-partum period. We studied the production of matrix metalloproteinase 9 (MMP-9), as a major contributor of tissue remodelling, in human myometrium at parturition. The regulation of proMMP-9 by interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) was also investigated in human myometrial smooth muscle cells. MMP-9 was present in myometrial smooth muscle cells, interstitial fibroblasts and inflammatory cells. The gelatinolytic activities of proMMP-9 in myometrium increased dramatically during labour. IL-1beta and TNF-alpha induced proMMP-9 in myometrial smooth muscle cells, but these effects did not seem to be mediated by protein kinase C. On the other hand, neither 17beta-oestradiol nor progesterone itself affected proMMP-9 production in myometrial smooth muscle cells. Moreover, progesterone, which is known as a physiological suppressor of MMP-9 in other species, did not decrease the IL-1beta- and TNF-alpha-induced production of proMMP-9. These results suggest that IL-1beta and TNF-alpha are effective up-regulators of proMMP-9 in the tissue remodelling of human myometrium during labour.

Induction of c-Jun mRNA without changes of estrogen and progesterone receptor expression in myometrium during human labor

To elucidate the endocrine mechanism of human parturition, the expression of c-Jun and c-Fos mRNA were examined in relation to estrogen receptor (ER) and progesterone receptor (PR) in human myometrium. c-Jun mRNA was detected in all myometrial tissues (n=5) during labor but not before labor (n=5) and in oxytocin-resistant postterm pregnancy (n=3). c-Fos mRNA was detected in only one myometrial tissue from a woman in labor. The distribution and intensity of immunostaining for ER and PR were semiquantitatively scored. During the late pregnancies, no significant difference was seen in the receptor scores for myometrial ER and PR between the patients who experienced labor and those who did not. Receptor scores for ER and PR were significantly lower in postterm pregnancy than in late pregnancy, regardless of the labor status. These data suggest that there are no changes in ER and PR in human myometrium during parturition. On the other hand, postterm pregnancy is associated with low ER and PR. c-Jun, induced during labor without changes in ER and PR, may play a role as a signaling mechanism in human myometrium.

Relationship between the fetal biophysical profile score, umbilical artery Doppler velocimetry, and fetal blood acid-base status determined by cordocentesis

OBJECTIVE

Fetal hypoxia-acidosis is part of the terminal pathway leading to intrauterine fetal death. A central premise of antepartum surveillance is that identification and timely delivery of the hypoxic or acidotic fetus will prevent intrauterine death and decrease long-term neurologic damage. The optimal method to identify fetal hypoxia-acidosis has not been determined. We attempted to compare the performance of the biophysical profile score and umbilical artery Doppler velocimetry in the identification of fetal acidemia, hypoxemia, and hypercarbia as determined by pH and gas analysis of fetal blood obtained by cordocentesis.

STUDY DESIGN

Fetal biophysical profile and umbilical artery Doppler velocimetry studies were performed before cordocentesis in 24 patients (26 to 40 weeks). Umbilical vein pH and blood gas values were determined in all cases. The pulsatility index of the umbilical artery was obtained with pulsed Doppler equipment. Receiver-operator characteristic curve analysis and stepwise multiple logistic regression were performed to examine the relationship between biophysical profile score, umbilical artery Doppler velocimetry, and acid-base status.

RESULTS

The prevalence of fetal acidemia (pH 2 SD below the mean for gestational age) was 41.7% (10/24). There was a significant relationship between the change in umbilical artery pulsatility index and fetal acidemia (chi 2 = 26.6, p < 0.001) and hypercarbia (chi 2 = 22.9, p < 0.001), but not hypoxemia (chi 2 = 1.0, p > 0.1), and between the biophysical profile score and fetal acidemia (chi 2 = 11.1, p < 0.001) and hypercarbia (chi 2 = 9.0, p < 0.005), but not hypoxemia (chi 2 = 2.3, p > 0.1). Stepwise multiple logistic regression demonstrated that umbilical artery Doppler velocimetry was a better explanatory variable for acidemia and hypercarbia than the biophysical profile score.

CONCLUSION

A strong relationship between the degree of fetal acidemia and hypercarbia and the results of umbilical artery Doppler velocimetry and biophysical profile was found. However, umbilical artery Doppler velocimetry was a better explanatory variable for these outcome than the biophysical profile score.