Takashi Ohba

Characterization of macrophages in the decidual atherotic spiral artery with special reference to the cytology of foam cells

“Acute atherosis” is characteristic in the spiral arteries of the placental bed of preeclampsia and a wide range of pregnancy disorders. The arterial lesion is histologically characterized by fibrinoid necrosis of the vessel walls with infiltration of foam cells, which under a light microscope appears similar to that seen in atherosclerosis. Although acute atherosis is currently considered as atheromatous-like lesions, the precise cellular mechanisms inducing these changes remain unelucidated. By histochemistry, immunohistochemistry, and electron microscopy, we investigated the decidual spiral arteries obtained by placental bed biopsy from 11 preeclamptic and 15 nonpreeclamptic women. In the decidual spiral arteries of preeclamptic patients, acute atherosis was observed in 23.5% (20/85 arteries). Fibrin deposition and accumulation of foam cells were observed more frequently in preeclamptic patients than in nonpreeclamptic patients. Endothelial cells remained in the atheromatous lesion, while the smooth muscle layer surrounding fibrin and foam cells became thin and was finally destroyed. The foam cells were immunohistochemically shown to be macrophages and neutral fat and phospholipids were histochemically demonstrated in them. Ultrastructurally, their cytoplasm was occupied by variously sized lipid droplets and membrane-bound myelin-like granules (myelinosomes). Plasma concentration of monocyte chemoattractant protein 1 (MCP-1), a potent monocyte chemoattractant factor, was significantly elevated in preeclamptic patients compared with normal healthy controls (P ≪ 0.01). In conclusion, injuries to the smooth muscle layer and intramural fibrinoid necrosis may result in infiltration of monocytes into the arterial walls, their maturation into macrophages, and the transformation into foam cells. Considering that atherosclerosis is developed by accumulation of lipid-laden macrophages and migration and proliferation of smooth muscle cells, the roles of macrophages in acute atherosis differ from those in atherosclerosis.

What we have learned from isolated cells from human ovary

In the ovary, morphodynamics of follicles with cyclic maturation, ovulation and repair occur under the control of various tropic factors. The ovarian functions have been mostly studied by using subhuman primates and non-primate animals because of the limited availability of closely staged human specimens. We have recently established the in vitro culture systems of ovarian surface epithelium (OSE) and granulosa cells of humans, and subsequently developed the immortalization of each cell. The immortalized cell lines may supply us advanced studies on ovarian disorders as well as its physiological functions. On the embryologically putative müllerian potential of coelomic epithelium, endometriosis can be explained by coelomic metaplasia from the peritoneal mesothelium, including OSE. We can microscopically observe a continuity from flat epithelial cells on the ovarian surface or within the cortical inclusion cysts to endometriotic gland cells. The primary human OSE cells exhibited a glandular-stromal structure similar to endometriosis when they were co-cultured with endometrial stromal cells in an estrogen-rich environment. Primary and immortalized OSE cells converted the estrone to estradiol, and expressed the genes for steroidogenic factor-1 (SF-1), p450arom and 17beta-HSDs. This character of OSE was, in part, similar to the granulosa cells. One of the immortalized OSE clone produces disseminated tumors mimicking undifferentiated carcinomas in nude mice. Ovarian granulosa cells play a key role in the functional maturation of the entire follicle. The molecular pathways in granulosa cells responsible for the growth, differentiation, and nursing the oocyte are still largely unknown. Our immortalized human granulosa cell line, GC1a, obtained from developing follicles, showed no steroid hormone biosynthesis, and no detectable expression of the genes for StAR or cytochrome p450 enzymes due to the lack of SF-1. Transfected SF-1 elicited estradiol secretion in GC1a cells with concomitant expression of the genes encoding the proteins for gonadal steroidogenesis. The enzymatic activity of 17beta-HSD was also achieved by SF-1 transgene. These results indicate that SF-1 controls the gene expression required for steroidogenesis in the human developing follicle. Clinically, immortalized GC1a cells from human origin, with steroidogenic capacity, may serve as a feeder layer for in vitro oocyte maturation. Further investigations of our immortalized OSE and granulosa cells of humans will allow us to clarify whether they have a single progenitor cell.

Hypertriglyceridemic acute pancreatitis during pregnancy: Prevention with diet therapy and ω-3 fatty acids in the following pregnancy

Acute pancreatitis complicating pregnancy is rare and has previously been associated with high mortality rates. We report a case of repeated hypertriglyceridemia during pregnancy. During the patients first pregnancy, acute pancreatitis was elicited in the third trimester by pregnancy-induced hypertriglyceridemia. The patient was treated successfully with a conservative treatment course. The hypertriglyceridemia recurred during her second pregnancy. She carried the pregnancy to term without incident while maintaining a diet low in fat diet and high in omega-3 fatty acids. Early diagnosis and intensive treatment can help to preserve the lives of the patient and the fetus. Prophylactic diet therapy and omega-3 fatty acids may prevent recurrent hypertriglyceridemia during pregnancy.

Expression of Cyclooxygenase 2 by Prostaglandin E2 in Human Endometrial Adenocarcinoma Cell Line HEC-1B

Abstract The regulation of expression of cyclooxygenase 2 (COX-2) was investigated by treatment with PGE2 in human endometrial adenocarcinoma cell line HEC-1B. One μM PGE2 could stimulate the expression of COX-2 approximately twofold in this cell line. The same concentration of PGE2 also stimulated activation of mitogen-activated protein kinase (MAP kinase) and protein kinase B (PKB). PGE2-induced MAP kinase activation was sensitive to a MAP kinase kinase (MEK) inhibitor, PD098059, and a protein kinase A inhibitor, H-89. PD098059 and H-89 also partially inhibited the expression of COX-2 stimulated by PGE2. PGE2 could stimulate the activation of PKB, which was sensitive to phosphatidylinositol-3-OH kinase (PI3K) inhibitor, wortmannin. Whereas wortmannin alone partially inhibited the expression of COX-2, a combination of wortmannin and PD098059 totally inhibited PGE2-mediated COX-2 expression. These results suggest that MAP kinase and PI3K pathways are stimulated with PGE2, and that both of these pathways are involved in the expression of COX-2. In addition, they also suggest that protein kinase A remains upstream of PGE2-induced activation of MAP kinase in HEC-1B cells.

Ovarian hyperstimulation syndrome-model rats; the manifestation and clinical implication.

Ovarian hyperstimulation syndrome (OHSS) is the most serious complication of ovulation induction with the gonadotropins. Though vascular endothelial growth factor (VEGF) has been implicated as a prime causative factor of OHSS progression, other factors must also be involved in the pathogenesis of OHSS. We have established an experimental model of OHSS in immature female rats. The ovarian weights and vascular permeability of the OHSS model rats are significantly increased by the ovarian stimulation with human chorionic gonadotropin (hCG). hCG elicits VEGF production in OHSS model rat ovaries. The addition of potent synthetic progesterone antagonist RU486, which reduces the extension of OHSS, attenuates the ovarian kinin and VEGF production dose-dependently whereas the VEGF gene expression was stable. VEGF protein detected in both the lung and the liver of the OHSS model rats is not affected at 24 h after the addition of hCG and RU486 in contrast to the ovary. Our results demonstrate that progesterone is implicated in the development of OHSS, in part, to enhance the ovarian VEGF production by post-transcriptional and organ-specific control.

Transvaginal Methotrexate Injection for the Treatment of Cesarean Scar Pregnancy: Efficacy and Subsequent Fecundity

STUDY OBJECTIVE To investigate the efficacy of local methotrexate (MTX) injections under transvaginal ultrasound guidance for treatment of cesarean scar pregnancy (CSP) and to assess fecundity after treatment. DESIGN Retrospective review (Canadian Task Force classification II-3). SETTING University hospital. PATIENTS Eight women with CSP. INTERVENTION Transvaginal MTX injection. MEASUREMENTS AND MAIN RESULTS We retrospectively reviewed 8 CSP cases treated with local MTX injection under transvaginal ultrasonographic guidance. In all cases, the serum human chorionic gonadotropin concentration was monitored and the gestational sac was evaluated using ultrasonography after treatment. Magnetic resonance imaging was performed as necessary. Patient clinical characteristics, clinical course after treatment, treatment efficacy, and fecundity after treatment in patients desiring subsequent pregnancies were evaluated. All 8 women were successfully treated without the need for blood transfusions or surgical procedures, although 2 required additional MTX therapy via local injection or systemic administration. The mean (SD) time to human chorionic gonadotropin normalization was 78.5 (37.7) days (range, 42-166 days). Four of 5 patients desiring subsequent pregnancies after the treatment had uneventful parturition, and recurrent CSP was diagnosed in 1 patient. CONCLUSIONS Transvaginal MTX injection was effective and safe as sole treatment of CSP. Although the treatment course tended to be long, this method can be considered the first choice of treatment in patients desiring future pregnancies. However, careful attention should be paid to the possibility of CSP recurrence.

Endometrioid adenocarcinoma arising in adenomyosis: elucidation by periodic magnetic resonance imaging evaluations

There are several case reports of adenocarcinomas developing within adenomyosis. However, there is no report demonstrating the natural course from adenomyosis to adenocarcinoma. We report a patient (a 41-year-old Japanese woman) who was observed every 6 months after being diagnosed with adenomyosis at our University Hospital. Although she went through menopause at age 51, she occasionally complained subsequently of abnormal genital bleeding. Eleven years after the initial diagnosis, endometrial cytology revealed the presence of malignant cells. Pelvic magnetic resonance imaging (MRI) demonstrated replacement of the adenomyotic lesion by a poorly demarcated lesion, compared to the findings on prior MRI. Consequently, we performed a modified radical hysterectomy and pelvic lymph node dissection, under a presumptive diagnosis of adenocarcinoma arising in adenomyosis. Histological diagnosis revealed an endometrioid adenocarcinoma (G3) transformed from adenomyotic epithelium, which was classified, according to the International Federation of Gynecology and Obstetrics, as stage Ic, pT1cN0M0. In this patient, periodic MRI evaluations, in conjunction with pathological examination, identified the transformation from adenomyosis to adenocarcinoma.

Fetal cell-free DNA fraction in maternal plasma is affected by fetal trisomy.

The purpose of this noninvasive prenatal testing (NIPT) study was to compare the fetal fraction of singleton gestations by gestational age, maternal characteristics and chromosome-specific aneuploidies as indicated by z-scores. This study was a multicenter prospective cohort study. Test data were collected from women who underwent NIPT by the massively parallel sequencing method. We used sequencing-based fetal fraction calculations in which we estimated fetal DNA fraction by simply counting the number of reads aligned within specific autosomal regions and applying a weighting scheme derived from a multivariate model. Relationships between fetal fractions and gestational age, maternal weight and height, and z-scores for chromosomes 21, 18 and 13 were assessed. A total of 7740 pregnant women enrolled in the study, of which 6993 met the study criteria. As expected, fetal fraction was inversely correlated with maternal weight (P<0.001). The median fetal fraction of samples with euploid result (n=6850) and trisomy 21 (n=70) were 13.7% and 13.6%, respectively. In contrast, the median fetal fraction values for samples with trisomies 18 (n=35) and 13 (n=9) were 11.0% and 8.0%, respectively. The fetal fraction of samples with trisomy 21 NIPT result is comparable to that of samples with euploid result. However, the fetal fractions of samples with trisomies 13 and 18 are significantly lower compared with that of euploid result. We conclude that it may make detecting these two trisomies more challenging.

MiR-21 is Enriched in the RNA-Induced Silencing Complex and Targets COL4A1 in Human Granulosa Cell Lines

MicroRNAs (miRNAs) are noncoding small RNAs that play important roles in a variety of physiological and pathological events. In this study, we performed large-scale profiling of EIF2C2-bound miRNAs in 3 human granulosa-derived cell lines (ie, KGN, HSOGT, and GC1a) by high-throughput sequencing and found that miR-21 accounted for more than 80% of EIF2C2-bound miRNAs, suggesting that it was enriched in the RNA-induced silencing complex (RISC) and played a functional role in human granulosa cell (GC) lines. We also found high expression levels of miR-21 in primary human GCs. Assuming that miR-21 target mRNAs are enriched in RISC, we performed cDNA cloning of EIF2C2-bound mRNAs in KGN cells. We identified COL4A1 mRNA as a miR-21 target in the GC lines. These data suggest that miR-21 is involved in the regulation of the synthesis of COL4A1, a component of the basement membrane surrounding the GC layer and granulosa-embedded extracellular structure.

Short RNA Duplexes Elicit RIG-I–Mediated Apoptosis in a Cell Type– and Length-Dependent Manner

Short double-stranded RNAs induce death in certain cell types without knocking down gene expression. Apoptosis Induced by dsRNAs Sequence-specific short interfering RNAs (siRNAs) are double-stranded RNAs (dsRNAs) that knock down the expression of target genes and have been used therapeutically, for example, to treat age-related macular degeneration. Although some of their effects depend on sequence-specific knockdown, some may be mediated by the innate immune system. Thus, a better understanding of cellular responses to various types of dsRNAs may help in the development of better therapies. Ishibashi et al. found that short dsRNAs induced apoptosis in cells derived from a human granulosa cell tumor (an ovarian cancer) without silencing gene expression. Apoptosis depended on the length of the dsRNAs but was independent of their sequence. The short dsRNAs stimulated expression of the gene encoding the cytosolic RNA sensor retinoic acid–inducible protein I (RIG-I). Increasing the abundance of RIG-I rendered previously resistant cells susceptible to dsRNA-induced apoptosis. Despite not having structures characteristic of dsRNAs that are detected by RIG-I, the apoptosis-inducing dsRNAs bound to and activated RIG-I, leading to activation of the kinase p38, which was required for apoptosis. Together, these data suggest an expanded role for cytosolic RNA sensors in mediating cellular responses to dsRNAs. Short double-stranded RNAs (dsRNAs) induce type I interferon (IFN)–mediated innate immune responses. In functional studies with short interfering RNAs or synthetic mimics of microRNA precursors in vitro, we found that short dsRNAs readily induced apoptosis in cells derived from human granulosa cell tumors, but not in other cell types. Apoptosis was independent of the sequence of the dsRNA, but depended on its length, and was induced by 23- and 24-nucleotide (nt) dsRNAs, but not by shorter dsRNAs (<22 nt) or by the long dsRNA polyinosinic-polycytidylic acid. Microarray analysis revealed that apoptosis was accompanied by the increased expression of IFN-stimulated genes; however, several lines of evidence showed that IFNs did not directly induce apoptosis. Subsequent analyses revealed that the short dsRNAs increased the expression of retinoic acid–inducible gene I (RIG-I) through dsRNA-activated protein kinase (PKR). Although these dsRNAs bore 3′ overhangs and nontriphosphate 5′ termini, which are not thought to be RIG-I–activating structures, the dsRNAs bound to RIG-I and triggered proapoptotic signaling mostly by activating RIG-I, which was followed by activation of the mitogen-activated protein kinase p38. Thus, we suggest that ligand recognition and subsequent signaling by RNA sensors are more complicated than previously believed. In addition, short dsRNAs may serve as pharmacological agents to target specific tumors, such as granulosa cell tumors.