Details of a Researcher - Tanaka, Mamoru

Papers - Tanaka, Mamoru

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Effects of maternal and fetal choline concentrations on the fetal growth and placental DNA methylation of 12 target genes related to fetal growth, adipogenesis, and energy metabolism

Nakanishi M., Funahashi N., Fukuoka H., Nammo T., Sato Y., Yoshihara H., Oishi H., Tanaka M., Yano T., Minoura S., Kato N., Yasuda K.

Journal of Obstetrics and Gynaecology Research (Journal of Obstetrics and Gynaecology Research) 47 ( 2 ) 734 - 744 2021.02

ISSN 13418076

© 2020 Japan Society of Obstetrics and Gynecology Aim: We performed a birth cohort study involving 124 mother–infant pairs to investigate whether placental DNA methylation is associated with maternal choline status and fetal development. Methods: Plasma choline concentration was assayed longitudinally in the 1st and 3rd trimesters and at term-pregnancy in mothers and cord blood. Placental DNA methylation was measured for 12 target candidate genes that are related to fetal growth, adipogenesis, lipid and energy metabolism, or long interspersed nuclear elements. Results: Higher maternal plasma and cord blood choline levels at term tended to associate with lower birthweight (r = −0.246, P < 0.013; r = −0.290, P < 0.002) and body mass index (BMI) at birth (r = 0.344, P < 1E−3; r = −0.360, P < 1E−3). The correlation between maternal plasma choline level and cord blood choline level was relatively modest (r = 0.049, P = 0.639). There was an inverse correlation between placental DNA methylation at the retinoid X receptor alpha (RXRA) gene and maternal plasma choline level (r = −0.188 to r = −0.452, P = 0.043 to P < 1E−3 at three points). RXRA methylation level was positively associated with birthweight and BMI at birth (r = 0.306, P = 0.001; r = 0.390, P < 1E−3). Further, RXRA methylation was inversely correlated with RXRA gene expression level (r = 0.333, P < 1E−3). Conclusion: Our results suggest that the association between maternal choline status and placental RXRA methylation represents a potential fetal programing mechanism contributing to fetal growth.

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Amniotic fluid stem cells as a novel strategy for the treatment of fetal and neonatal neurological diseases

Abe Y., Ochiai D., Sato Y., Otani T., Fukutake M., Ikenoue S., Kasuga Y., Tanaka M.

Placenta (Placenta) 104 247 - 252 2021.01

ISSN 01434004

© 2021 Elsevier Ltd Even in the context of modern medicine, infants with fetal and neonatal neurological diseases such as cerebral palsy and myelomeningocele suffer serious long-lasting impairment due to the irreversible neuronal damage. The promotion of neurologically intact survival in patients with perinatal intractable neurological diseases requires the development of novel strategies. One promising strategy involves the use of human amniotic fluid stem cells (hAFSCs), which have attracted much attention in recent years and are known to exert anti-inflammatory and neuroprotective effects. In recent years, the therapeutic effects of hAFSCs on fetal-neonatal neurological diseases have become evident as per intense research efforts by our group and others. Specifically, hAFSCs administered into the nasal cavity migrated to the brain and controlled local inflammation in a rodent model of neonatal hypoxic-ischemic encephalopathy. In contrast, hAFSCs administered intraperitoneally did not migrate to the brain; they rather formed spheroids in the abdominal cavity, resulting in the suppression of systemic inflammation (including in the brain) via the secretion of anti-inflammatory cytokines in concert with peritoneal macrophages in a rodent model of periventricular leukomalacia. Moreover, studies in a rat model of myelomeningocele suggested that hAFSCs administered in utero secreted hepatocyte growth factor and protected the exposed spinal cord during pregnancy. Importantly, autologous hAFSCs, whose use for fetal-neonatal treatment does not raise ethical issues, can be collected during pregnancy and prepared in sufficient numbers for therapeutic use. This article outlines the results of preclinical research on fetal stem cell therapy, mainly involving hAFSCs, in the context of perinatal neurological diseases.

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Mitochondrial replacement by genome transfer in human oocytes: Efficacy, concerns, and legality

Yamada M., Sato S., Ooka R., Akashi K., Nakamura A., Miyado K., Akutsu H., Tanaka M.

Reproductive Medicine and Biology (Reproductive Medicine and Biology) 20 ( 1 ) 53 - 61 2021.01

ISSN 14455781

© 2020 The Authors. Reproductive Medicine and Biology published by John Wiley & Sons Australia, Ltd on behalf of Japan Society for Reproductive Medicine. Background: Pathogenic mitochondrial (mt)DNA mutations, which often cause life-threatening disorders, are maternally inherited via the cytoplasm of oocytes. Mitochondrial replacement therapy (MRT) is expected to prevent second-generation transmission of mtDNA mutations. However, MRT may affect the function of respiratory chain complexes comprised of both nuclear and mitochondrial proteins. Methods: Based on the literature and current regulatory guidelines (especially in Japan), we analyzed and reviewed the recent developments in human models of MRT. Main findings: MRT does not compromise pre-implantation development or stem cell isolation. Mitochondrial function in stem cells after MRT is also normal. Although mtDNA carryover is usually less than 0.5%, even low levels of heteroplasmy can affect the stability of the mtDNA genotype, and directional or stochastic mtDNA drift occurs in a subset of stem cell lines (mtDNA genetic drift). MRT could prevent serious genetic disorders from being passed on to the offspring. However, it should be noted that this technique currently poses significant risks for use in embryos designed for implantation. Conclusion: The maternal genome is fundamentally compatible with different mitochondrial genotypes, and vertical inheritance is not required for normal mitochondrial function. Unresolved questions regarding mtDNA genetic drift can be addressed by basic research using MRT.

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Differences in fetal fractional limb volume changes in normal and gestational diabetic pregnancies: an exploratory observational study

Akiba Y., Ikenoue S., Endo T., Kasuga Y., Ochiai D., Miyakoshi K., Ishii R., Yakubo K., Tanaka M.

BJOG: An International Journal of Obstetrics and Gynaecology (BJOG: An International Journal of Obstetrics and Gynaecology) 128 ( 2 ) 329 - 335 2021.01

ISSN 14700328

© 2020 Royal College of Obstetricians and Gynaecologists Objective: Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation. Design: Exploratory observational study. Setting: Saitama Municipal Hospital. Sample: A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women. Methods: AVol and TVol were assessed between 20 and 37 weeks’ gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology. Main outcome measures: AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks’ gestation). Results: Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks’ gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks’ gestation (P < 0.05). TVol was not statistically different between the groups across gestation. Conclusions: Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM. Tweetable abstract: AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks’ gestation.

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Risk of preterm birth after the excisional surgery for cervical lesions: a propensity-score matching study in Japan

Miyakoshi K., Itakura A., Abe T., Kondoh E., Terao Y., Tabata T., Hamada H., Tanaka K., Tanaka M., Kanayama N., Takeda S.

Journal of Maternal-Fetal and Neonatal Medicine (Journal of Maternal-Fetal and Neonatal Medicine) 34 ( 6 ) 845 - 851 2021

ISSN 14767058

© 2019 Informa UK Limited, trading as Taylor & Francis Group. Introduction: There is a paucity of data on the risk of preterm birth subcategorized by gestational age in pregnancies after the pre-pregnancy excisional treatment for cervical lesions. In addition, little is known about the effect of prophylactic cerclage on the risk of preterm birth. The aim of this study was to investigate the risk of preterm birth stratified by gestational period and its reduction by the prophylactic cerclage in women with prior excisional surgery. Materials and methods: We retrospectively analyzed a cohort of singleton pregnancies in the Japan Perinatal Registry Network Database (2013–2014, n = 307,001). Cases included pregnancies after the surgery (i.e. conization and loop electrosurgical excision procedure). Controls comprised the propensity-score matched pregnancies without pre-pregnancy surgery. The main outcome was the occurrence of preterm birth. The effect of prophylactic cervical cerclage on the risk of preterm birth after the excisional surgery was also examined using cases. Results: In the propensity-score matched population (cases, n = 1389; controls, n = 1389), cases exhibited a higher risk of preterm birth and preterm prelabor rupture of membranes (PROM), compared with controls (preterm birth: 25.3 versus 10.6%; preterm PROM: 14.0 versus 3.5%: both p <.0001). Odds ratios (OR; 95% confidence interval [CI]) for preterm birth at 22–27 weeks, 28–31 weeks, 32–33 weeks, and 34–36 weeks were 3.4 [1.8–6.5], 4.6 [2.7–7.7], 2.2 [1.4–3.5], and 2.1 [1.6–2.7], respectively. The association was stronger for preterm PROM at earlier gestational age (22–27 weeks, 28–31 weeks, 32–33 weeks, and 34–36 weeks: 5.2 [2.3–11.8], 7.1 [3.4–15.0], 3.8 [1.7–8.3], and 3.9 [1.8–4.6], respectively). In cases, 171 underwent the prophylactic cervical cerclage. The occurrence of preterm birth and preterm PROM was comparable between those with and without the cerclage (28.7 versus 24.2, and 12.9 versus 13.3%, respectively). Conclusions: Pre-pregnancy excisional cervical surgery was associated with the increased risk of preterm birth, especially before 32 weeks of gestation. The prophylactic cerclage did not reduce the risk of preterm birth.

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Prophylactic therapy with human amniotic fluid stem cells improves long-term cognitive impairment in rat neonatal sepsis survivors

Abe Y., Ochiai D., Sato Y., Kanzaki S., Ikenoue S., Kasuga Y., Tanaka M.

International Journal of Molecular Sciences (International Journal of Molecular Sciences) 21 ( 24 ) 1 - 12 2020.12

ISSN 16616596

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. A systemic inflammatory response induces multiple organ dysfunction and results in poor long-term neurological outcomes in neonatal sepsis. However, there is no effective therapy for treating or preventing neonatal sepsis besides antibiotics and supportive care. Therefore, a novel strategy to improve neonatal sepsis-related morbidity and mortality is desirable. Recently, we reported that prophylactic therapy with human amniotic stem cells (hAFSCs) improved survival in a rat model of lipopolysaccharide (LPS)-induced neonatal sepsis through immunomodulation. Besides improving the mortality, increasing survival without major morbidities is an important goal of neonatal intensive care for neonatal sepsis. This study investigated long-term neurological outcomes in neonatal sepsis survivors treated with hAFSCs using the LPS-induced neonatal sepsis model in rats. We found that prophylactic therapy with hAFSCs improved spatial awareness and memory-based behavior in neonatal sepsis survivors at adolescence in rats. The treatment suppressed acute reactive gliosis and subsequently reduced astrogliosis in the hippocampal region over a long period of assessment. To the best of our knowledge, this is the first report that proves the concept that hAFSC treatment improves cognitive impairment in neonatal sepsis survivors. We demonstrate the efficacy of hAFSC therapy in improving the mortality and morbidity associated with neonatal sepsis.

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UDP-glucose, a cellular danger signal, and nucleotide receptor P2Y14 enhance the invasion of human extravillous trophoblast cells

Katakura S., Takao T., Arase T., Yoshimasa Y., Tomisato S., Uchida S., Masuda H., Uchida H., Tanaka M., Maruyama T.

Placenta (Placenta) 101 194 - 203 2020.11

ISSN 01434004

© 2020 The Authors Introduction: P2Y14, one of the P2Y purinergic G-protein coupled receptors, is expressed in a variety of cells and tissues. Its ligand, UDP-glucose (UDPG), is released from damaged and stress-stimulated cells and acts as a danger signal via P2Y14. Thus, P2Y14 plays an important role in immunological defense systems. Here, we aimed to elucidate the expression, localization, and role of P2Y14 in human trophoblasts and the placenta. Methods: Human chorionic villus and placental tissues were subjected to immunostaining for P2Y14 protein and an extravillous trophoblast (EVT) marker, HLA-G. We examined the expression of P2Y14 and the effect of UDPG on cell proliferation and invasion in an EVT cell line, HTR-8/SVneo, using an MTS assay and a Transwell assay, respectively. We tested the effect of UDPG on cell invasion in P2Y14-underexpressing HTR-8/SVneo clones established by the lentiviral introduction of shRNA for P2RY14 mRNA. Results: Immunostaining revealed that P2Y14 was exclusively expressed by EVTs. P2RY14 mRNA and P2Y14 protein were expressed in HTR-8/SVneo cells. UDPG did not affect cell proliferation but it did enhance invasion. Inhibition of P2Y14 and decreasing the expression of P2Y14 suppressed UDPG-mediated invasive activity. Conclusions: These results showed that EVT selectively expressed P2Y14 and that P2Y14 was positively involved in UDPG-enhanced EVT invasion. It suggests the possible existence of a danger signal-mediated physiological system at the fetomaternal interface where UDPG released from maternal tissues through destruction by EVT invasion may accelerate EVT invasion, allowing EVTs to undergo successful placentation and vascular remodeling.

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Universal screening for SARS-CoV-2 in asymptomatic obstetric patients in Tokyo, Japan

Ochiai D., Kasuga Y., Iida M., Ikenoue S., Tanaka M.

International Journal of Gynecology and Obstetrics (International Journal of Gynecology and Obstetrics) 150 ( 2 ) 268 - 269 2020.08

ISSN 00207292

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Prophylactic therapy with human amniotic fluid stem cells improved survival in a rat model of lipopolysaccharide-induced neonatal sepsis through immunomodulation via aggregates with peritoneal macrophages

Sato Y., Ochiai D., Abe Y., Masuda H., Fukutake M., Ikenoue S., Kasuga Y., Shimoda M., Kanai Y., Tanaka M.

Stem Cell Research and Therapy (Stem Cell Research and Therapy) 11 ( 1 ) 2020.07

© 2020 The Author(s). Background: Despite recent advances in neonatal care, sepsis remains a leading cause of mortality in neonates. Mesenchymal stem cells derived from various tissues, such as bone marrow, umbilical cord, and adipose tissue, have beneficial effects on adult sepsis. Although human amniotic fluid stem cells (hAFSCs) have mesenchymal stem cell properties, the efficacy of hAFSCs on neonatal sepsis is yet to be elucidated. This study aimed to investigate the therapeutic potential of hAFSCs on neonatal sepsis using a rat model of lipopolysaccharide (LPS)-induced sepsis. Methods: hAFSCs were isolated as CD117-positive cells from human amniotic fluid. Three-day-old rat pups were intraperitoneally treated with LPS to mimic neonatal sepsis. hAFSCs were administered either 3 h before or at 0, 3, or 24 h after LPS exposure. Serum inflammatory cytokine levels, gene expression profiles from spleens, and multiple organ damage were analyzed. hAFSC localization was determined in vivo. In vitro LPS stimulation tests were performed using neonatal rat peritoneal macrophages co-cultured with hAFSCs in a cell-cell contact-dependent/independent manner. Immunoregulation in the spleen was determined using a DNA microarray analysis. Results: Prophylactic therapy with hAFSCs improved survival in the LPS-treated rats while the hAFSCs transplantation after LPS exposure did not elicit a therapeutic response. Therefore, hAFSC pretreatment was used for all subsequent studies. Inflammatory cytokine levels were elevated after LPS injection, which was attenuated by hAFSC pretreatment. Subsequently, inflammation-induced damages in the brain, lungs, and liver were ameliorated. hAFSCs aggregated with peritoneal macrophages and/or transiently accumulated in the liver, mesentery, and peritoneum. Paracrine factors released by hAFSCs induced M1-M2 macrophage polarization in a cell-cell contact-independent manner. Direct contact between hAFSCs and peritoneal macrophages further enhanced the polarization. Microarray analysis of the spleen showed that hAFSC pretreatment reduced the expression of genes involved in apoptosis and inflammation and subsequently suppressed toll-like receptor 4 signaling pathways. Conclusions: Prophylactic therapy with hAFSCs improved survival in a rat model of LPS-induced neonatal sepsis. These effects might be mediated by a phenotypic switch from M1 to M2 in peritoneal macrophages, triggered by hAFSCs in a cell-cell contact-dependent/independent manner and the subsequent immunomodulation of the spleen.

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Impaired fetal growth in mothers with inadequate gestational weight gain: a retrospective study in Japanese uncomplicated pregnancy

Ikenoue S., Miyakoshi K., Kasuga Y., Ochiai D., Matsumoto T., Tanaka M.

Journal of Maternal-Fetal and Neonatal Medicine (Journal of Maternal-Fetal and Neonatal Medicine) 33 ( 13 ) 2227 - 2231 2020.07

ISSN 14767058

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. Introduction: The average birth weight in Japan has gradually decreased and the number of low birth weight infant has increased over the last 30 years. Japanese pregnant women are characterized with lower prevalence of obesity than those in other developed countries, and maternal underweight before pregnancy is independently associated with low birth weight. However, the association between maternal inadequate gestational weight gain (GWG) and the risk of small for gestational age (SGA) in Japanese uncomplicated pregnant women has not been fully understood. This study aimed to examine the effect of maternal inadequate GWG on the risk of SGA in Japanese uncomplicated pregnancies. Methods: We retrospectively analyzed uncomplicated Japanese singleton pregnancies that delivered at term gestation in our institution from 2006 to 2016. The association between GWG and birth weight was analyzed by multiple linear regression. Potential confounding factors included maternal age, parity, prepregnancy BMI, and neonatal sex. The association between inadequate GWG and SGA was also examined by logistic regression. Results: A total of 3837 mother–neonate dyads were analyzed. Maternal GWG was 10.1 ± 3.7 kg (mean ± SD), and 2529 (66%) had inadequate GWG. After adjusting for confounding factors, GWG significantly correlated with birth weight (standardized β = 0.199, p <.001). Inadequate GWG increased the risk of delivering SGA neonate (adjusted odds ratio (aOR) = 1.97 [1.45–2.68], p <.001). This association was particularly pronounced in underweight (aOR = 2.95 [1.38–6.29], p =.005) and normal weight mothers (aOR = 1.79 [1.27–2.52], p =.001), and not in overweight/obese mothers (p =.115). Conclusion: Maternal GWG is associated with birth weight in Japanese women with uncomplicated singleton pregnancies. Inadequate GWG is an important risk factor of SGA, particularly in non-obese women. The present finding would potentially provide further evidence that promoting adequate gestational weight gain in Japanese underweight and normal weight mothers would reduce SGA, as well as metabolic dysfunction in later life.

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The impact of parental unaffected allele combination on the diagnostic outcome in the preimplantation genetic testing for myotonic dystrophy type 1 in Japanese ancestry

Senba H., Sueoka K., Sato S., Higuchi N., Mizuguchi Y., Sato K., Tanaka M.

Reproductive Medicine and Biology (Reproductive Medicine and Biology) 19 ( 3 ) 265 - 269 2020.07

ISSN 14455781

© 2020 The Authors. Reproductive Medicine and Biology published by John Wiley & Sons Australia, Ltd on behalf of Japan Society for Reproductive Medicine. Purpose: The objective is to clarify the practical problem of the preimplantation genetic testing (PGT) for myotonic dystrophy type 1 (DM1) in Japanese subjects. Methods: For the 32 couples who consented to participate in PGT for DM1, CTG repeats number on the unaffected alleles was analyzed. Based on the allele combination, they were classified into 3 groups by the number of diagnostic allelic pattern; “full informative,” “semi informative,” and “noninformative.” According to the Japan Society of Obstetrics and Gynecology (JSOG) principle, PGT was performed using the direct diagnosis to the 288 embryos from the 17 couples who received the ethical approval from both our institution and JSOG. Results: In the 32 couples, the frequency of CTG repeats on the unaffected alleles showed bimodal distribution. The “full informative,” “semi informative,” and “noninformative” couples accounted for 46.9% (15/32 couples), 46.9% (15/32 couples) and 6.2% (2/32 couples), respectively. The transferable embryos accounted for 28.9% (33/114 embryos) in the “full informative” couples, although it was limited to 12.6% (22/174 embryos) in the “semi informative” couples. Conclusion: The loss of unaffected embryos which cannot be diagnosed as transferable was a clinically major problem and implied an increase in oocyte retrieval, especially for “semi informative” couples.

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Right aortic arch with an aberrant left subclavian artery: Sonographic features by HDlive Flow imaging

Endo T., Ochiai D., Tanaka M.

Cardiology in the Young (Cardiology in the Young) 30 ( 6 ) 892 - 893 2020.06

ISSN 10479511

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Transvaginal ultrasound features of the residual cervix in pregnancy after radical trachelectomy

Kasuga Y., Miyakoshi K., Tanaka M.

Journal of Medical Ultrasonics (Journal of Medical Ultrasonics) 47 ( 2 ) 335 - 337 2020.04

ISSN 13464523

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Impaired early phase insulin secretion associated with gestational diabetes mellitus in underweight women

Kasuga Y., Miyakoshi K., Saisho Y., Ikenoue S., Ochiai D., Tanaka M.

Journal of Maternal-Fetal and Neonatal Medicine (Journal of Maternal-Fetal and Neonatal Medicine) 2020

ISSN 14767058

© 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group. Background: No reports have focused on the clinical and metabolic characteristics of gestational diabetes (GDM) in underweight women. The aim of this study is to investigate the clinical and metabolic features of underweight GDM (pregravid BMI, <18.5 kg/m2: U-GDM). Materials and methods: Women diagnosed with GDM were categorized based on their pre-pregnancy BMI as either underweight (n = 49) or normal weight (pregravid BMI, 18.5–25.0 kg/m2: n = 271: N-GDM). During the study period, GDM was diagnosed using the International Association of Diabetes in Pregnancy Study Group criteria. Women with multi-fetal pregnancies, fetal congenital anomalies, overt diabetes in pregnancy, and pre-gestational diabetes mellitus were excluded. Results: There were no notable differences in maternal age at delivery and the rate of nulliparous between the U-GDM and N-GDM groups. Regarding antepartum oral glucose tolerance test profiles, women with U-GDM exhibited significantly lower fasting plasma glucose (FPG) levels than those with N-GDM (p <.01). The Insulinogenic Index of women with U-GDM was significantly lower than that of women with N-GDM (p <.05). Conclusion: Impaired early phase insulin secretion was associated with GDM onset in underweight women.

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Changes in bone metabolic profile associated with pregnancy or lactation

Miyamoto T., Miyakoshi K., Sato Y., Kasuga Y., Ikenoue S., Miyamoto K., Nishiwaki Y., Tanaka M., Nakamura M., Matsumoto M.

Scientific Reports (Scientific Reports) 9 ( 1 ) 2019.12

© 2019, The Author(s). Calcium and nutrients are transferred from mothers to fetuses or infants during pregnancy or lactation, respectively, promoting metabolic changes in the mother, many uncharacterized. To evaluate these changes, we undertook two parallel studies. In one we analyzed fourteen clinical cases of vertebral fragility fractures, at or before three months after partum, in mothers who breastfed their infants. In the other, we enrolled 79 additional pregnant subjects, some who chose to breastfeed and others who did not, and analyzed changes in bone metabolic status starting between 34 and 36 weeks of gestation and ending one month after partum. In the larger group, bone-resorbing and bone-forming parameters such as serum TRACP5b and osteocalcin, respectively, significantly increased after partum. Among parameters that changed after partum, serum PTH and the bone-resorbing markers serum TRACP5b and urine NTX were significantly higher in mothers who only breastfed infants compared to mothers who fed infants formula or a mix of both. However, bone-forming parameters were comparable between breastfeeding and non-breast-feeding groups after partum, suggesting that elevated bone-resorption occurs only in the breastfeeding group. Radiographic analysis after partum demonstrated that no subject among the 79 analyzed showed vertebral fractures, even those who breastfed exclusively. Among fracture cases analyzed, subjects exhibited significantly lower bone mineral density than did non-fracture cases in breastfeeding-only subjects. We conclude that bone metabolic status significantly changes over the period between pregnancy and post-partum lactation, and that low bone mineral density seen in a small subset of breastfeeding-only cases likely causes post-partum vertebral fragility fractures.

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Ultrasound Findings of Varices at the Site of Uterovaginal Anastomosis in a Pregnant Woman After Radical Trachelectomy

Kasuga Y., Miyakoshi K., Tanaka M.

Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine (Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine) 38 ( 12 ) 3363 - 3364 2019.12

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Impact of Oxidative Stress on Age-Associated Decline in Oocyte Developmental Competence

Sasaki H., Hamatani T., Kamijo S., Iwai M., Kobanawa M., Ogawa S., Miyado K., Tanaka M.

Frontiers in Endocrinology (Frontiers in Endocrinology) 10 2019.11

© Copyright © 2019 Sasaki, Hamatani, Kamijo, Iwai, Kobanawa, Ogawa, Miyado and Tanaka. Reproductive capacity in women starts to decline beyond their mid-30s and pregnancies in older women result in higher rates of miscarriage with aneuploidy. Age-related decline in fertility is strongly attributed to ovarian aging, diminished ovarian reserves, and decreased developmental competence of oocytes. In this review, we discuss the underlying mechanisms of age-related decline in oocyte quality, focusing on oxidative stress (OS) in oocytes. The primary cause is the accumulation of spontaneous damage to the mitochondria arising from increased reactive oxygen species (ROS) in oocytes, generated by the mitochondria themselves during daily biological metabolism. Mitochondrial dysfunction reduces ATP synthesis and influences the meiotic spindle assembly responsible for chromosomal segregation. Moreover, reproductively aged oocytes produce a decline in the fidelity of the protective mechanisms against ROS, namely the ROS-scavenging metabolism, repair of ROS-damaged DNA, and the proteasome and autophagy system for ROS-damaged proteins. Accordingly, increased ROS and increased vulnerability of oocytes to ROS lead to spindle instability, chromosomal abnormalities, telomere shortening, and reduced developmental competence of aged oocytes.

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In Utero Amniotic Fluid Stem Cell Therapy Protects Against Myelomeningocele via Spinal Cord Coverage and Hepatocyte Growth Factor Secretion

Abe Y., Ochiai D., Masuda H., Sato Y., Otani T., Fukutake M., Ikenoue S., Miyakoshi K., Okano H., Tanaka M.

Stem Cells Translational Medicine (Stem Cells Translational Medicine) 8 ( 11 ) 1170 - 1179 2019.11

ISSN 21576564

© 2019 The Authors. Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press Despite the poor prognosis associated with myelomeningocele (MMC), the options for prenatal treatments are still limited. Recently, fetal cellular therapy has become a new option for treating birth defects, although the therapeutic effects and mechanisms associated with such treatments remain unclear. The use of human amniotic fluid stem cells (hAFSCs) is ideal with respect to immunoreactivity and cell propagation. The prenatal diagnosis of MMC during early stages of pregnancy could allow for the ex vivo proliferation and modulation of autologous hAFSCs for use in utero stem cell therapy. Therefore, we investigated the therapeutic effects and mechanisms of hAFSCs-based treatment for fetal MMC. hAFSCs were isolated as CD117-positive cells from the amniotic fluid of 15- to 17-week pregnant women who underwent amniocentesis for prenatal diagnosis and consented to this study. Rat dams were exposed to retinoic acid to induce fetal MMC and were subsequently injected with hAFSCs in each amniotic cavity. We measured the exposed area of the spinal cord and hepatocyte growth factor (HGF) levels at the lesion. The exposed spinal area of the hAFSC-treated group was significantly smaller than that of the control group. Immunohistochemical analysis demonstrated a reduction in neuronal damage such as neurodegeneration and astrogliosis in the hAFSC-treated group. Additionally, in lesions of the hAFSC-treated group, HGF expression was upregulated and HGF-positive hAFSCs were identified, suggesting that these cells migrated to the lesion and secreted HGF to suppress neuronal damage and induce neurogenesis. Therefore, in utero hAFSC therapy could become a novel strategy for fetal MMC. Stem Cells Translational Medicine 2019;8:1170–1179.

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Zscan5b Deficiency Impairs DNA Damage Response and Causes Chromosomal Aberrations during Mitosis

Ogawa S., Yamada M., Nakamura A., Sugawara T., Nakamura A., Miyajima S., Harada Y., Ooka R., Okawa R., Miyauchi J., Tsumura H., Yoshimura Y., Miyado K., Akutsu H., Tanaka M., Umezawa A., Hamatani T.

Stem Cell Reports (Stem Cell Reports) 12 ( 6 ) 1366 - 1379 2019.06

ISSN 22136711

© 2019 The Authors Zygotic genome activation (ZGA) begins after fertilization and is essential for establishing pluripotency and genome stability. However, it is unclear how ZGA genes prevent mitotic errors. Here we show that knockout of the ZGA gene Zscan5b, which encodes a SCAN domain with C2H2 zinc fingers, causes a high incidence of chromosomal abnormalities in embryonic stem cells (ESCs), and leads to the development of early-stage cancers. After irradiation, Zscan5b-deficient ESCs displayed significantly increased levels of γ-H2AX despite increased expression of the DNA repair genes Rad51l3 and Bard. Re-expression of Zscan5b reduced γ-H2AX content, implying a role for Zscan5b in DNA damage repair processes. A co-immunoprecipitation analysis showed that Zscan5b bound to the linker histone H1, suggesting that Zscan5b may protect chromosomal architecture. Our report demonstrates that the ZGA gene Zscan5b is involved in genomic integrity and acts to promote DNA damage repair and regulate chromatin dynamics during mitosis. In this article, Yamada and colleagues show that Zscan5b deficiency increases DNA stress, compromises chromosomal structure during mitosis, and leads to the development of early-stage cancers. Zscan5b deficiency may offer a murine model of human chromosomal breakage syndromes.

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The orientation of a decellularized uterine scaffold determines the tissue topology and architecture of the regenerated uterus in rats

Miki F., Maruyama T., Miyazaki K., Takao T., Yoshimasa Y., Katakura S., Hihara H., Uchida S., Masuda H., Uchida H., Nagai T., Shibata S., Tanaka M.

Biology of Reproduction (Biology of Reproduction) 100 ( 5 ) 1215 - 1227 2019.05

ISSN 00063363

© 2019 The Author(s) 2019. Published by Oxford University Press on behalf of Society for the Study of Reproduction. A decellularized uterine scaffold (DUS) prepared from rats permits recellularization and regeneration of uterine tissues when placed onto a partially excised uterus and supports pregnancy in a fashion comparable to the intact uterus. The underlying extracellular matrix (ECM) together with an acellular, perfusable vascular architecture preserved in DUS is thought to be responsible for appropriate regeneration of the uterus. To investigate this concept, we examined the effect of the orientation of the DUS-preserving ECM and the vascular architecture on uterine regeneration through placement of a DUS onto a partially defective uterine area in the reversed orientation such that the luminal face of the DUS was outside and the serosal face was inside. We characterized the tissue structure and function of the regenerated uterus, comparing the outcome to that when the DUS was placed in the correct orientation. Histological analysis revealed that aberrant structures including ectopic location of glands and an abnormal lining of smooth muscle layers were observed significantly more frequently in the reversed group than in the correct group (70% vs. 30%, P < 0.05). Despite the changes in tissue topology, the uteri regenerated with an incorrectly oriented DUS could achieve pregnancy in a way similar to uteri regenerated with a correctly oriented DUS. These results suggest that DUS-driven ECM orientation determines the regenerated uterus structure. Using DUS in the correct orientation is preferable when clinically applied. The disoriented DUS may deteriorate the tissue topology leading to structural disease of the uterus even though the fertility potential is not immediately affected.

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