Jong Yun Hwang

Aspirin prevents TNF-α-induced endothelial cell dysfunction by regulating the NF-κB-dependent miR-155/eNOS pathway: Role of a miR-155/eNOS axis in preeclampsia

ABSTRACT Preeclampsia is an inflammatory disease with endothelial cell dysfunction that occurs via decreased endothelial nitric oxide synthase/nitric oxide (eNOS/NO) activity. Aspirin reduces the incidence of hypertensive pregnancy complications. However, the underlying mechanism has not been clearly explained. Here, we found that tumor necrosis factor (TNF)‐&agr;, microRNA (miR)−155, and eNOS levels as well as endothelial redox phenotype were differentially regulated in preeclamptic patients, implying the involvement of TNF‐&agr;‐ and redox signal‐mediated miR‐155 biogenesis and eNOS downregulation in the pathogenesis of preeclampsia. Aspirin prevented the TNF‐&agr;‐mediated increase in miR‐155 biogenesis and decreases in eNOS expression and NO/cGMP production in cultured human umbilical vein endothelial cells (HUVECs). Similar effects of aspirin were also observed in HUVECs treated with H2O2. The preventive effects of aspirin was associated with the inhibition of nuclear factor‐&kgr;B (NF‐&kgr;B)‐dependent MIR155HG (miR‐155 host gene) expression. Aspirin recovered the TNF‐&agr;‐mediated decrease in wild‐type, but not mutant, eNOS 3′‐untranslated region reporter activity, whose effect was blocked by miR‐155 mimic. Moreover, aspirin prevented TNF‐&agr;‐mediated endothelial cell dysfunction associated with impaired vasorelaxation, angiogenesis, and trophoblast invasion, and the preventive effects were blocked by miR‐155 mimic or an eNOS inhibitor. Aspirin rescued TNF‐&agr;‐mediated eNOS downregulation coupled with endothelial dysfunction by inhibiting NF‐&kgr;B‐dependent transcriptional miR‐155 biogenesis. Thus, the redox‐sensitive NF‐&kgr;B/miR‐155/eNOS axis may be crucial in the pathogenesis of vascular disorders including preeclampsia. HIGHLIGHTSTNF‐&agr;, miR‐155, and eNOS are differentially regulated in preeclamptic patients.Aspirin prevents TNF‐&agr;‐mediated miR‐155 biogenesis and eNOS downregulation.Aspirin preserves vascular function by blocking NF‐kB‐mediated eNOS downregulation.Thus, the NF‐kB/miR‐155/eNOS pathway is crucial for the pathogenesis of preeclampsia.

Diagnosis of fetal femoral fracture by midtrimester three-dimensional ultrasound

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C-peptide protects against hyperglycemic memory and vascular endothelial cell apoptosis.

C-peptide exerts protective effects against diabetic complications; however, its role in inhibiting hyperglycemic memory (HGM) has not been elucidated. We investigated the beneficial effect of C-peptide on HGM-induced vascular damage in vitro and in vivo using human umbilical vein endothelial cells and diabetic mice. HGM induced apoptosis by persistent generation of intracellular ROS and sustained formation of ONOO(-) and nitrotyrosine. These HGM-induced intracellular events were normalized by treatment with C-peptide, but not insulin, in endothelial cells. C-peptide also inhibited persistent upregulation of p53 and activation of mitochondrial adaptor p66(shc) after glucose normalization. Further, C-peptide replacement therapy prevented persistent generation of ROS and ONOO(-) in the aorta of diabetic mice whose glucose levels were normalized by the administration of insulin. C-peptide, but not insulin, also prevented HGM-induced endothelial apoptosis in the murine diabetic aorta. This study highlights a promising role for C-peptide in preventing HGM-induced intracellular events and diabetic vascular damage.

Serum from pregnant women with gestational diabetes mellitus increases the expression of FABP4 mRNA in primary subcutaneous human pre-adipocytes

Objective Gestational diabetes mellitus (GDM) is defined as glucose intolerance first detected during pregnancy. It can result in pregnancy complications such as birth injury, stillbirth. Fatty acid-binding protein 4 (FABP4), found in adipose tissue, is associated with insulin resistance, and type 2 diabetes. The aim of this study was to investigate whether FABP4 in the placenta and decidua of pregnant women with GDM is higher than that in normal pregnant women, and whether serum from pregnant women with GDM may cause adipocytes to secrete more FABP4 than does serum from a normal pregnant group. Methods We obtained placentas, deciduas, and serum from 12 pregnant women with GDM and 12 normal pregnant women and performed enzyme-linked immunosorbent assay, real time quantitative-polymerase chain reaction. We cultured human pre-adipocytes for 17 days with GDM and non-GDM serum and performed western blot, real time quantitative-polymerase chain reaction, and oil red O staining. Results Expression of FABP4 in serum, placenta and decidua of pregnant women with GDM was significantly higher than that in normal pregnant women. Serum from pregnant women with GDM increased the expression of FABP4 mRNA and decreased the expression of adiponectin mRNA in human pre-adipocytes significantly. Adipocyte cultured in GDM serum showed significantly greater lipid accumulation than those cultured in normal serum. Conclusion Our results suggest that FABP4 is higher in placenta and decidua from pregnant women with GDM. Increased circulating FABP4 in maternal serum from pregnant women with GDM may originate from adipocytes and the placenta. Circulating FABP4 can induce increased insulin resistance and decreased insulin sensitivity.

Carbon monoxide prevents TNF-α-induced eNOS downregulation by inhibiting NF-κB-responsive miR-155-5p biogenesis

Heme oxygenase-1-derived carbon monoxide prevents inflammatory vascular disorders. To date, there is no clear evidence that HO-1/CO prevents endothelial dysfunction associated with the downregulation of endothelial NO synthesis in human endothelial cells stimulated with TNF-α. Here, we found that the CO-releasing compound CORM-2 prevented TNF-α-mediated decreases in eNOS expression and NO/cGMP production, without affecting eNOS promoter activity, by maintaining the functional activity of the eNOS mRNA 3′-untranslated region. By contrast, CORM-2 inhibited MIR155HG expression and miR-155-5p biogenesis in TNF-α-stimulated endothelial cells, resulting in recovery of the 3′-UTR activity of eNOS mRNA, a target of miR-155-5p. The beneficial effect of CORM-2 was blocked by an NF-κB inhibitor, a miR-155-5p mimic, a HO-1 inhibitor and siRNA against HO-1, indicating that CO rescues TNF-α-induced eNOS downregulation through NF-κB-responsive miR-155-5p expression via HO-1 induction; similar protective effects of ectopic HO-1 expression and bilirubin were observed in endothelial cells treated with TNF-α. Moreover, heme degradation products, except iron and N-acetylcysteine prevented H2O2-mediated miR-155-5p biogenesis and eNOS downregulation. These data demonstrate that CO prevents TNF-α-mediated eNOS downregulation by inhibiting redox-sensitive miR-155-5p biogenesis through a positive forward circuit between CO and HO-1 induction. This circuit may play an important preventive role in inflammatory endothelial dysfunction associated with human vascular diseases.

Mirror syndrome associated with fetal leukemia

Mirror syndrome describes the association of fetal and placental hydrops with maternal edema. This case is the first reported case of mirror syndrome relative to fetal leukemia. We suggest that fetal leukemia can have a major impact on mirror syndrome, and provide a brief review of the literature related to this syndrome.

A study on postpartum symptoms and their related factors in Korea

OBJECTIVEnThis study was aimed to identify the physical and mental state of women after delivery, to investigate the factors that influence those, and to examine the effects of postpartum care performance, which is traditionally believed to be appropriate care in Korea, on womens physical and mental status.nnnMATERIALS AND METHODSnA total of 148 women who visited our hospital for postpartum check-up on the 2(nd) week or 6(th) week after delivery were selected. We researched postpartum care methods using a questionnaire and had the women self-evaluate their postpartum symptoms. Depression was evaluated using the Beck Depression Inventory.nnnRESULTSnThe average points of the 27 postpartum symptoms was 2.70 points (from 1 = very good to 5 = very bad). Seventy-two women had depression. Factors related to postpartum symptoms and depression were smoking before pregnancy, low marital satisfaction, bad mood during and after pregnancy, lack of support from husbands, and bad quality of sleep during puerperium. Treating the joints of hands carefully when milking breasts, and avoiding squatting down, demonstrated a negative correlation with the average points of postpartum symptoms. Multivariate linear regression analysis showed that mood during puerperium and Beck Depression Inventory points were significant factors related to the average points of postpartum symptoms and that the degree of support from husbands and mood during pregnancy were statistically related with depression.nnnCONCLUSIONnMany women complained of postpartum discomfort. Although, while some postpartum care methods which are traditionally believed to be appropriate care in Korea can be helpful to womens recovery, most of them are not. We confirmed that physical symptoms and depression are closely related to each other.

Huge Fetal Cervicomediastinal Thymic Cyst: Successful Antenatal Intervention for Vaginal Delivery

The thymus is located in front of the heart and is an important immune organ that produces T cells. Congenital thymic cysts result from the degeneration of aberrant thymic tissue after the arrest of thymic primordium migration along the thymopharyngeal tract.1 Although congenital thymic cysts can occur anywhere from the neck to the mediastinum, most are in the neck.2 If such a cyst is in the cervicomediastinal area, it is difficult to distinguish from other cystic masses, such as lymphangiomas and bronchogenic cysts.3 They are often diagnosed as a result of the deformity that develops with cyst growth because congenital thymic cysts are asymptomatic.4 A large cyst can compress the adjacent organs and cause tracheal obstruction and a mediastinal shift. Such cysts need to be removed surgically.5 To our knowledge, 2 cases of fetal thymic cysts have been reported prenatally. Those cases did not need any additional intervention in utero because one cyst did not produce a mass effect,6 and the other did not change in size until delivery.2 There is no consensus on the in utero obstetric management of thymic cysts and which delivery mode is better because most are detected postnatally. Here we report antenatal intervention to prevent immediate postnatal complications from a large cervicomediastinal thymic cyst that extended from the upper neck to the diaphragm with a mediastinal shift, tracheal compression, and tachycardia. A 28-year-old healthy primigravida was referred after detection of a huge fetal mediastinal cystic mass during a sonographic examination at 38 weeks’ gestation. There was no history of medical, surgical, or familial disease. The initial fetal sonography (Accuvix XQ; Medison Co, Ltd, Hongcheon, Korea) showed a huge hypoechoic cystic mass with a septum measuring 64 × 23 × 32 mm extending from the neck into the diaphragm. The mass had welldefined borders with no connection to the heart, great vessels, or trachea. However, the mass displaced the heart to the left posterior thorax and compressed the trachea (Figure 1A). Fetal tachycardia was also present. Color Doppler sonography showed no blood flow in the mass. Fetal biometric measurements were appropriate for gestational age, and no other fetal findings were identified. Fetal magnetic resonance imaging (MRI) was performed the same day to evaluate the characteristics and anatomic connections of the mass to the surrounding tissues. It showed a 60 × 21 × 34-mm tubular cystic mass with a linear septum extending from the anterior neck beneath the tongue base to the anterior mediastinum above the diaphragm. It compressed the heart to the left posterior thorax (Figure 1B). The differential diagnosis of the cyst included a thymic cyst, lymphangioma, and a bronchogenic cyst. There was difficulty distinguishing these diagnoses because the cyst was too large for its origin to be established, and it had two septa. On the basis of the fetal sonography and MRI, we concluded that the cyst had a mass effect, causing the fetal tachycardia and mediastinal shift, and that the huge cyst would trigger respiratory distress immediately after delivery. Therefore, if we did not reduce the size of the cyst, we would have to perform a cesarean delivery for ex utero intrapartum treatment to avoid respiratory distress. In addition, the cyst might have ruptured during a normal vaginal delivery. Therefore, we performed sonographically guided aspiration to decompress the cyst immediately before vaginal delivery. Because percutaneous fetal intervention can be associated with complications, such as placental hemorrhage, rupture of the chorioamniotic membrane, maternal infection, and maternal-fetal hemorrhage,7 we obtained informed consent from the parents. The skin was prepared with a povidone-iodine solution and draped using standard sterile techniques, and the procedure was performed with sterile gel. A 22-gauge, 89-mm spinal needle (Hakko Co, Tokyo, Japan) was advanced into the cyst under direct sonographic guidance through the fetal anterior neck. Thirty milliliters of clear viscous fluid were aspirated from the cyst through the spinal needle. Cytologic examination revealed some mature squamous cells. After aspiration, fetal MRI and sonography were repeated and showed a marked decrease in the size of the cystic mass, which now measured 29 × 11 × 17 mm, and mass effects were now absent in the anterior neck and mediastinum (Figure 1, C and D). In addition, the tachycardia disappeared. Three days after the intervention, a female neonate weighing 3670 g was born by a normal vaginal delivery at 40 weeks’ gestation with Apgar scores of 8 and 9 at 1 and 5 minutes, respectively. Her condition was stable with no signs of respiratory distress. On physical examination, there was no palpable mass in the neck. Postnatal sonography showed a small cystic mass measuring 30 × 12 × 19 mm. At 31 days of age, a painless mass in the neck was noted. Sonography of the neck and chest showed a recurrence of the mass, measuring 78 × 31 × 40 mm. At 3 months of age, the cyst was removed surgically because it had collapsed the left lung totally and caused atelectasis of the right lower lung. The histologic findings confirmed the diagnosis of a unilocular thymic cyst with a stratified squamous epithelial lining.

Gene expression of heme oxygenase-1 and nitric oxide synthase on trophoblast of preeclampsia

Methods Placenta were obtained from women with normal pregnancies (n=15) and severe preeclamptic (n=15) after informed consent and under the approval of IRB of Kangwon National University Hospital. The severe preeclampsia was diagnosed as high blood pressure and proteinuria. High blood pressure was defi ned as systolic blood pressure of >160 mm Hg or diastolic pressure of >110 mm Hg and proteinuria was defi ned as urine protein of >2 g/24 hr. We investigated mRNA expression of HO-1, iNOS and eNOS in both groups by real time polymerase chain reaction and immunohistochemistry. The Student’s t-test was used for statistical analysis with SPSS ver. 12.0. P<0.05 was considered to be statistically signifi cant.

The Effects of Heme Oxygenase By-Products on the Proliferation and Invasion of HUVECs, HTR-8/SVneo Cells, 3A(tPA 30-1) Cells, and HESCs Under Varying Oxygen Concentrations

Objective: Abnormal spiral artery remodeling during early pregnancy leads to preeclampsia. The proliferation and invasion of trophoblasts in pregnancy are important for spiral artery remodeling. This study examined whether heme oxygenase (HO) by-products (carbon monoxide biliverdin, and iron) play roles in regulating the restoration of proliferation and invasion of human umbilical vein endothelial cells (HUVECs), HTR-8/SV-neo cells originating from first-trimester trophoblasts, 3A(tPA 30-1) obtained from term trophoblasts, and human endometrial stromal cells (HESCs) inhibited by zinc protoporphyrin IX (Znpp-9). Study Design: We explored whether HO by-products restored the proliferation and invasion of HUVECs, HTR-8/SVneo cells, 3A(tPA 30-1) cells, and HESCs inhibited by Znpp-9 depending on the oxygen concentration. Results: Bilirubin promoted proliferation of HUVECs, HTR-8/SVneo cells, 3A(tPA-30-1) cells, and HESCs under both hypoxic and normoxic conditions. Biliverdin also promoted invasion of HUVECs, HTR-8/SVneo cells, 3A(tPA30-1) cells, and HESCs under both hypoxic and normoxic conditions. Carbon monoxide-releasing molecule 2 promoted the proliferation and invasion of specific cell types depending on the oxygen concentration. Conclusion: Our data suggest that HO by-products differentially stimulate the proliferation and invasion of cells involved in pregnancy maintenance. When HO by-products are considered to be stimulants during the invasion and proliferation of such cells, both target cells and the gestational period should be considered.