Hirobumi Asakura

Hydroxysteroid (17-β) Dehydrogenase 1 Is Dysregulated by Mir-210 and Mir-518c That Are Aberrantly Expressed in Preeclamptic Placentas: A Novel Marker for Predicting Preeclampsia

In this study, to search for novel preeclampsia (PE) biomarkers, we focused on microRNA expression and function in the human placenta complicated with PE. By comprehensive analyses of microRNA expression, we identified 22 microRNAs significantly upregulated in preeclamptic placentas, 5 of which were predicted in silico to commonly target the mRNA encoding hydroxysteroid (17-&bgr;) dehydrogenase 1 (HSD17B1), a steroidogenetic enzyme expressed predominantly in the placenta. In vivo HSD17B1 expression, at both the mRNA and protein levels, was significantly decreased in preeclamptic placentas. Of these microRNAs, miR-210 and miR-518c were experimentally validated to target HSD17B1 by luciferase assay, real-time PCR, and ELISA. Furthermore, we found that plasma HSD17B1 protein levels in preeclamptic pregnant women reflected the decrease of its placental expression. Moreover, a prospective cohort study of plasma HSD17B1 revealed a significant reduction of plasma HSD17B1 levels in pregnant women at 20 to 23 and 27 to 30 weeks of gestation before PE onset compared with those with normal pregnancies. The sensitivities/specificities for predicting PE at 20 to 23 and 27 to 30 weeks of gestation were 0.75/0.67 (cutoff value=21.9 ng/mL) and 0.88/0.51 (cutoff value=30.5 ng/mL), and the odds ratios were 6.09 (95% CI: 2.35–15.77) and 7.83 (95% CI: 1.70–36.14), respectively. We conclude that HSD17B1 is dysregulated by miR-210 and miR-518c that are aberrantly expressed in preeclamptic placenta and that reducing plasma level of HSD17B1 precedes the onset of PE and is a potential prognostic factor for PE.

Developmental changes in mitochondrial activity and energy metabolism in fetal and neonatal rat brain

Experiments were undertaken to investigate mitochondrial activity and energy metabolism in the developing rat brain from the late fetal stage to the neonatal stage. Samples of cerebral cortical tissue were obtained from fetuses at 14, 16, 18, and 20 days of gestation, and from pups at 1 h, 1 day and 7 days after birth. Mitochondrial respiration was measured polarographically using homogenates. Fetal and neonatal brains were frozen in situ and fluorometric enzymatic techniques were used for the analysis of ATP, ADP, AMP, and lactate. In the fetal brain, there was a gradual increase in stimulated (+ADP) and uncoupled respiratory rates using glutamate and malate as substrates, from 14 days to 20 days of gestation, together with a moderate increase in ATP concentration and in the sum total of adenine nucleotides, and a significant decrease in lactate. Since non-stimulated (-ADP) respiratory rates did not change with increasing gestational age, the respiratory control ratio appeared to increase over the same period. An increase in mitochondrial activity was more pronounced immediately after birth, together with a marked increase in ATP concentration and in the sum total of adenine nucleotides. The highest rate of mitochondrial respiration was observed in 1-hour-old pups. These results indicate that, in the rat brain, there is maturation of oxidative metabolism in mitochondria that is initiated in late gestation. Acceleration in mitochondrial respiration occurs immediately after birth in order to maintain high-energy phosphate levels, and this may be crucial for the successful outcome of the newborn.

Effect of α-phenyl-N-tert-butyl nitrone (PBN) on fetal cerebral energy metabolism during intrauterine ischemia and reperfusion in rats

The objective of the present study was to explore whether a free radical spin trap agent, α-phenyl-N-tert-butyl nitrone (PBN), influences bioenergetic failure induced in the 20-day-old fetal brain by 30 min of intrauterine ischemia in Wistar rats. Fetal brains were frozen in situ at the end of ischemia and after 1, 2, and 4 h of recirculation for analysis of ATP, ADP, AMP, and lactate. PBN or vehicle was given 1 h after recirculation. Tissue oxygen tension was evaluated in placental and fetal cerebral tissues throughout the whole periods of 30 min of ischemia and 4 h of recirculation. Ischemia was associated with a decrease in ATP concentration and an increase in lactate concentration (p < 0.001). Recirculation (1 and 2 h) led to a recovery of ATP concentration, but continued reflow (4 h) was associated with a secondary deterioration of high-energy phosphates (p < 0.01). Lactate concentration increased during this recovery period. This deterioration was prevented by PBN (p < 0.05). After 30 min of ischemia, tissue oxygen tension in placenta and fetal brain decreased to about 30% and 50% of control, respectively. However, recirculation brought about a recovery of oxygen delivery. The results indicate that although during the early time period after ischemia fetal cerebral energy metabolism is maintained by an acceleration of the anaerobic glycolytic rate, secondary deterioration of cellular bioenergetic state develops in the immature fetal brain. This deterioration may be due to mitochondrial dysfunction, which may be induced by oxygen-derived free radicals, and not by compromised microcirculation.

Preoperative diagnosis of dehiscence of the lower uterine segment in patients with a single previous Caesarean section

Summary: Preoperative diagnoses were checked during surgery in 39 patients who underwent elective repeat Caesarean section with (n = 20) and without (as control, n = 19) a preoperative diagnosis of wall dehiscence (thinning) of the lower uterine segment (LUS). All patients were examined manually and by ultrasonography at 36 weeks gestation before labour. A preoperative diagnosis of wall dehiscence was made when the wall thickness was less than 2 mm and/or the patient felt pain and tenderness in the LUS. Surgical findings of dehiscence were j defined as a subperitoneal separation of the uterine I scar in the LUS. The sensitivity and specificity of our ultrasonographic evaluations were found to be 100% and 83% (p < 0.05), respectively. On the other hand, there were no surgical findings of dehiscence in patients who felt pain and tenderness in the LUS with a wall thickness greater than 2 mm, nor among those in the control group.

Influence of mild hypothermia on delayed mitochondrial dysfunction after transient intrauterine ischemia in the immature rat brain

The aim of this study was to determine the effect of different maternal thermal conditions during transient intrauterine ischemia on the mitochondrial respiratory activities in the immature rat brain. On 17 days of gestation, transient intrauterine ischemia was induced by 30 min of right uterine artery occlusion under hypothermic (33.5-34.5 degrees C, n=6), normothermic (36.5-37.5 degrees C, n=6), and hyperthermic conditions (39.5-40.5 degrees C, n=6). All of the pups were delivered by cesarean section at 21 days of gestation and cerebral neocortical tissue was sampled 1 h after delivery. The mitochondrial respiration was measured polarographically in homogenates. In the ischemic uterine horn, ADP-stimulated respiration of the normothermia and the hyperthermia groups decreased significantly to 73 and 74% of the non-ischemic controls, respectively. Since non-stimulated respiration remained unchanged, the respiratory control ratio (RCR) of the normothermia and the hyperthermia groups decreased significantly to 59 and 54% of the non-ischemic levels, respectively. In contrast, the mitochondrial respiratory activities of the hypothermia group showed no differences between the non-ischemic and the ischemic uterine horns. The results demonstrate that mild maternal hypothermia ameliorates the cerebral mitochondrial dysfunction in neonatal rats after intrauterine ischemia due to transient uterine artery occlusion and suggest that maternal thermal conditions, particularly during uteroplacental insufficiency, have important implications for the neuropathological outcome of the newborn.

Severity of hyperemesis gravidarum correlates with serum levels of reverse T3.

Abstract To investigate the possible physiological relevance of extra-thyroidal production of reverse T3 (rT3) in hyperemesis gravidarum, measurements of serum rT3, free T3 (FT3), free T4, (FT4), and nonesterified fatty acids (NEFA) were correlated with weight loss of hyperemetic women. All the thyroid hormones, NEFAs and weight loss were significantly higher in hyperemesis gravidarum than in control subjects, and also higher than in those with milder symptoms of morning sickness (p < 0.05). Elevations of FT3, FT4 and NEFAs correlated with the extent of weight loss, the latter taken as the index of the severity of hyperemesis gravidarum (p < 0.05). Only rT3 correlated with both weight loss and the rate of lipolysis, as reflected by elevations of NEFAs (p < 0.05). The data are consistent with a shift from T3 to rT3 as products of 5′-monodeiodination of thyroxine in hyperemesis gravidarum. Because reverse T3 is physiologically inactive a control mechanism may be postulated wherein T3 production is minimized, thereby reducing weight loss and lipolysis in patients with hyperemesis gravidarum.

Significance of cervical gland area in predicting preterm birth for patients with threatened preterm delivery: comparison with cervical length and fetal fibronectin.

Background/Aims: Absent cervical gland area (CGA) has been considered a predictor of preterm delivery (PTD) for women at low risk. Predictive efficacy was analyzed in women at high risk for PTD and compared with cervical length (CL) <20 mm and fetal fibronectin (fFN) in cervicovaginal secretions. Methods: Case notes were reviewed for 108 subjects with gestation of 22–33 weeks who had been admitted to hospital with threatened PTD. The uterine cervix was observed by vaginal sonography and fFN was sampled on admission. Relationships between findings and outcome of PTD at <34 weeks’ gestation were analyzed. Results: Delivery at <34 weeks’ gestation occurred in 14.8% of patients. Absent CGA (68.8%), short CL (75.0%), short CL without CGA (62.5%) and positive fFN (62.5%) were more frequent in these patients than in patients undelivered at <34 weeks’ gestation (p < 0.05). Logistic regression analysis identified positive fFN and short CL with absent CGA as independent predictors for PTD (p < 0.0001). The mean interval from admission to delivery was 2.9 weeks in cases with fFN and both sonographic findings, compared to 9.3 weeks in cases with fFN but both sonographic finding (p = 0.0005). Conclusion: Short CL with absent CGA represents an independent predictor for PTD, as does fFN.

Intrauterine therapy for the acutely enlarging fetal cystic hygroma.

Enlarged fetal cystic hygroma is known to cause life-threatening complications such as fetal hydrops and neonatal respiratory difficulty. A 28-year-old Japanese woman, gravida 0, presented with fetal cystic hygroma at 23 weeks of gestation. There were no other structural malformations or hydrops detected by ultrasonographic examination. In addition, the karyotype was diagnosed as normal through amniotic fluid analysis. The cystic lesion showed acute enlargement and intrauterine sclerotherapy using OK-432 was performed at 26 weeks. The size of the cyst initially decreased, which was followed by a gradual increase. A viable 3,098 g male infant was delivered by cesarean section at 37 weeks without any other complications. The infant had no clinical difficulty during the neonatal period and later underwent a surgical removal of the remaining cystic lesion. Cases of fetal cystic hygroma showing acute enlargement without other complications are considered good candidates for intrauterine therapy to prevent subsequent complications.

Continuous Observation of Nitric Oxide Production in the Fetal Rat Brain during Uteroplacental Ischemia

Objectives: To demonstrate real-time changes in nitric oxide (NO) production within fetal rat brain during uteroplacental ischemia and subsequent reperfusion. Methods: Using a selective microsensor for NO, changes in NO electrocurrent in the brains of 10 fetal rats at gestational day 20 were observed during and after 30 min occlusion of uterine vessels in anesthetized pregnant rats. Results: The NO electrocurrent reached 397 ± 71.0% of the control level 30 min after occlusion and increased throughout the observation (p < 0.05) until placental administration of 1 M of L-NAME. In contrast, no significant changes in NO electrocurrent were found in 7 sham operated rats. Conclusion: An NO-specific microelectric sensor detected excessive NO production by fetal rat brains in response to uteroplacental ischemia.

Expression and role of nestin in human cervical intraepithelial neoplasia and cervical cancer.

Nestin expression reportedly correlates with aggressive growth, metastasis, poor prognosis and presence of cancer stem cells (CSCs) in various tumors. In this study, we determined the expression and role of nestin in cervical intraepithelial neoplasia (CIN) and cervical cancer. We performed immunohistochemical and in situ hybridization analyses of nestin in 26 cases for each stage of CIN and 55 cervical cancer tissue samples. To examine the role of nestin in cervical cancer cells, we stably transfected expression vectors containing nestin cDNA into ME-180 cells. We studied the effects of increased nestin expression on cell proliferation, cell motility, invasion as well as sphere and soft agar formation. Nestin was not localized in the squamous epithelium in normal cervical tissues, but it was weakly expressed in the basal squamous epithelium of CIN 1. In CIN 2, nestin was localized to the basal to lower 2/3 of the squamous epithelium, whereas in CIN 3, it was localized to the majority of the squamous epithelium. Nestin was detected in all cases of invasive cervical cancer. Nestin mRNA was expressed in both ME-180 and CaSki cells. Growth rate, cell motility and invasion ability of stably nestin-transfected ME-180 cells were not different from empty vector-transfected ME-180 (mock cells). However, the nestin-transfected ME-180 cells formed more colonies and spheres compared to the mock cells. These findings suggest that nestin plays important roles in carcinogenesis and tumor formation of cervical cancer cells. Nestin may closely correlate with regulation of CSCs.