Akihiko Wakatsuki

Melatonin preserves fetal growth in rats by protecting against ischemia/reperfusion-induced oxidative/nitrosative mitochondrial damage in the placenta.

Abstract:u2002 We have previously demonstrated that melatonin protects against ischemia/reperfusion‐induced oxidative damage to mitochondria in the fetal rat brain. The purpose of the present study was to evaluate the effects of maternally administered melatonin on ischemia/reperfusion‐induced oxidative placental damage and fetal growth restriction in rats. The utero‐ovarian arteries were occluded bilaterally for 30u2003min in rats on day 16 of pregnancy to induce fetal ischemia. Reperfusion was achieved by releasing the occlusion and restoring circulation. Melatonin solution (20u2003μg/mL) or the vehicle alone was administered orally during pregnancy. A sham operation was performed in control rats, which were treated with vehicle alone. Laparotomy was performed on day 20 of pregnancy and the number and weight of fetal rats and placentas were measured. Placental mitochondrial respiratory control index (RCI), a marker of mitochondrial respiratory activity, was also calculated for each group. Using immunohistochemistry, we investigated the degree of immunostaining of 8‐hydroxy‐2‐deoxyguanosine (8‐OHdG), a marker of oxidative DNA damage, and redox factor‐1(ref‐1), which repairs DNA damage and acts as a redox‐modifying factor in rat placenta. Predictably, the ischemia/reperfusion operation significantly decreased the weight of fetal rats and placentas and the RCI. Melatonin prevented ischemia/reperfusion‐induced changes in RCI (1.55u2003±u20030.05 to 1.83u2003±u20030.09, Pu2003<u20030.05) and fetal growth (3.04u2003±u20030.17 to 3.90u2003±u20030.1, Pu2003<u20030.0001). Immunohistochemistry revealed significant positive staining for 8‐OHdG and ref‐1 following ischemia/reperfusion; these effects were also reduced by melatonin treatment. Results indicated that ischemia/reperfusion‐induced oxidative placental DNA and mitochondrial damage and fetal growth restriction can be prevented by maternally administered melatonin.

Placental oxidative DNA damage and its repair in preeclamptic women with fetal growth restriction

Preeclampsia is frequently accompanied by fetal growth restriction (FGR). Preeclampsia increases oxygen free radical production, and the resulting oxidative stress impairs placental blood flow. To determine whether placental oxidative stress is associated with FGR in preeclamptic women, we evaluated placental oxidative DNA damage and its repair in 13 preeclamptic women with FGR, 10 preeclamptic women without FGR, and 11 healthy pregnant women without complications. We measured maternal and umbilical serum derivatives of reactive oxygen metabolites (d-ROMs), as a marker of oxygen free radicals, and pulsatility index (PI) of uterine and umbilical arteries, and performed an immunohistochemical analysis to measure the proportion of nuclei in the placental trophoblast that stained positive for 8-hydroxy-2-deoxyguanosin (8-OHdG), an indicator of oxidative DNA damage, and redox factor-1 (ref-1), indicative of the repair function towards oxidative DNA damage. D-ROMs were increased in the maternal blood of both preeclamptic groups (with FGR, 687.3 ± 50.4 CARR U, p < 0.01; without FGR, 750.4 ± 87.2 CARR U, p < 0.001) compared with controls (504.7 ± 25.0 CARR U). In contrast, d-ROM levels in the umbilical artery were elevated in preeclamptic women with FGR (134.9 ± 13.3 CARR U, p < 0.01), but not in preeclamptic women without FGR (44.0 ± 7.3 CARR U) compared with controls (38.2 ± 5.0 CARR U). Mean PI for uterine arteries was significantly increased in both preeclamptic groups, and the PI in preeclamptic women with FGR was significantly greater than that in women without FGR (0.94 ± 0.07 vs. 1.31 ± 0.07, p < 0.001). The PI for umbilical arteries was significantly increased in preeclamptic women with FGR (0.90 ± 0.05vs. 1.19 ± 0.07, p < 0.001), but not in preeclamptic women without FGR. The proportion of nuclei positive for 8-OHdG was higher in both groups of preeclamptic women than in the control group, but was higher in preeclamptic women with FGR (0.21 ± 0.05 vs. 0.87 ± 0.01, p < 0.001). The proportion of nuclei positive for ref-1 was higher in preeclamptic women without FGR (0.54 ± 0.06, p < 0.001) than in the control group, whereas the proportion did not differ significantly between normal and preeclamptic women with FGR. Our findings indicate that increased oxidative stress and disrupted compensatory reaction against placental oxidative DNA damage may be associated with FGR in preeclamptic women.

The severity of hypoxic changes and oxidative DNA damage in the placenta of early-onset preeclamptic women and fetal growth restriction.

Objective: To investigate the relation between the severity of hypoxic changes and oxidative DNA damage in the placenta of early and late-onset preeclampic women and fetal growth restriction (FGR), serum parameters of oxidative stress, placental hypoxic change, and oxidative DNA damage were determined. Methods: We examined 10 participants with uncomplicated pregnancies, 13 with early-onset and 12 with late-onset preeclampsia. Maternal and umbilical plasma derivatives of reactive oxygen metabolites (d-ROMs) were measured as markers of oxygen free radicals. Immunohistochemical analysis was performed to measure the proportion of placental trophoblast cell nuclei staining positive for 8-hydroxy-2’-deoxyguanosine (8-OHdG), redox factor-1 (ref-1), and hypoxia-induced factor-1α (HIF-1α), which are markers of oxidative DNA damage, repair functions, and hypoxia status, respectively. Results: 8-OHdG was higher in both preeclamptic groups, but significantly higher in the early-onset preeclamptic group. Ref-1 was higher in the late-onset preeclamptic group. HIF-1α was higher in both preeclamptic groups, with a tendency towards a higher in the early-onset preeclamptic group. Conclusions: Our findings indicate that the severity of hypoxic changes and oxidative DNA damage are greater in the placenta of women with early-onset preeclampsia, and that the prolonged preeclamptic conditions may reduce placental blood flow, ultimately leading to FGR.

Japan Atherosclerosis Society (JAS) Guidelines for Prevention of Atherosclerotic Cardiovascular Diseases 2017

Toray Industries, Inc., Tokyo, Japan Department of Diabetes, Metabolism and Endocrinology, Chiba University Graduate School of Medicine, Chiba, Japan National Center for Geriatrics and Gerontology, Aichi, Japan Department of Internal Medicine and Cardiology, Gifu Prefectural General Medical Center, Gifu, Japan Division of Diabetes and Metabolism, Department of Internal Medicine, Iwate Medical University, Iwate, Japan Division of Endocrinology and Metabolism, Department of Medicine, Jichi Medical University, Tochigi, Japan Center for Integrated Medical Research, Hiroshima University Hospital, Hiroshima, Japan Egusa Genshi Clinic, Hiroshima, Japan Department of Cardiovascular Medicine, Juntendo University, Tokyo, Japan Preventive Medicine and Public Health, Keio University School of Medicine, Tokyo, Japan Biomedical Informatics, Osaka University, Osaka, Japan Division of Cardiology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan Department of Community Health Systems Nursing, Ehime University Graduate School of Medicine, Ehime, Japan Department of Vascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan Department of Vascular Surgery, Saitama Medical Center, Saitama, Japan Chief Health Management Department, Mitsui Chemicals Inc., Tokyo, Japan Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan Department of Neurology, Kita-Harima Medical Center, Hyogo, Japan Department of Internal Medicine, Mizonokuchi Hospital, Teikyo University School of Medicine, Kanagawa, Japan Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan Tsukasa Health Care Hospital, Kagoshima, Japan Faculty of Nutrition, Division of Clinical Nutrition, Kobe Gakuin University, Hyogo, Japan Department of Food and Nutrition, Faculty of Human Sciences and Design, Japan Women’s University, Tokyo, Japan 25 Department of Preventive Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan Department of Medical Statistics, Toho University, Tokyo, Japan Department of Clinical Innovative Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan Department of Laboratory Medicine, Jikei University Kashiwa Hospital, Chiba, Japan Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Osaka, Japan Department of Obstetrics and Gynecology, Aichi Medical University, Aichi, Japan 31 Department of Community Medicine, Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan Rinku General Medical Center, Osaka, Japan

Prophylactic administration of melatonin to the mother throughout pregnancy can protect against oxidative cerebral damage in neonatal rats

Objective: The purpose of this study was to investigate whether prophylactic administration of melatonin to the mother throughout pregnancy could protect against ischemia/reperfusion (I/R)-induced oxidative brain damage in neonatal rats. Methods: The utero-ovarian arteries were occluded bilaterally for 30u2009min in female Wistar rats on day 16 of pregnancy to induce fetal ischemia. Reperfusion was achieved by releasing the occlusion and restoring circulation. A sham operation was performed in control rats. Melatonin solution or vehicle alone was administrated orally throughout pregnancy. We collected brain mitochondria from neonatal rats, evaluated mitochondrial structure by electron microscopy, and measured the respiratory control index (RCI) as an indicator of mitochondrial respiratory activity as well as the concentration of thiobarbituric acid-reactive substances (TBARS), a marker of oxidative stress. Histological analysis was performed at the Cornu Ammonis 1 (CA1) and Cornu Ammonis 3 (CA3) regions of the hippocampus. Results: I/R significantly reduced the RCI and significantly elevated the concentration of TBARS. Melatonin treatment reversed these effects, resulting in values similar to that in untreated, sham-ischemic animals. Electron microscopic evaluation showed that the number of intact mitochondria decreased in the I/R group, while melatonin treatment preserved them. Histological analysis revealed a decrease in the ratio of normal to whole pyramidal cell number in the CA1 and CA3 regions in the I/R group. While melatonin administration protected against degeneration. Conclusions: These results indicate that prophylactic administration of melatonin to the mother throughout pregnancy may prevent I/R-induced oxidative brain damage in neonatal rats.

Therapeutic Effects of Maternal Melatonin Administration on Ischemia/Reperfusion-Induced Oxidative Cerebral Damage in Neonatal Rats

Background: We have previously demonstrated that prophylactic administration of melatonin to pregnant rats can protect against ischemia/reperfusion (I/R)-induced oxidative cerebral damage in fetal rats. However, the effects of maternal administration of melatonin after an ischemic episode on the brains of neonatal rats exposed to oxidative stress in utero have not been evaluated. Objectives: The purpose of the present study was to investigate whether maternal administration of melatonin after an ischemic episode can prevent oxidative cerebral damage in neonatal rats. Methods: The utero-ovarian arteries were occluded bilaterally for 30 min in female Wistar rats on day 16 of pregnancy to induce fetal ischemia. Reperfusion was achieved by releasing the occlusion and restoring circulation. Melatonin solution (10 mg/kg) or vehicle was injected intraperitoneally at 0, 1, 3, 6, and 12 h after reperfusion. After surgery, melatonin solution (20 µg/ml) or vehicle was administered freely via drinking water up to vaginal delivery. Control rats underwent a sham operation. We collected brain tissue from neonatal rats that were delivered naturally and measured the respiratory control index (RCI) as indicators of mitochondrial respiratory activity. Histological evaluation was performed on the cornu ammonis (CA1) and CA3 regions of the hippocampus. Results: I/R significantly reduced the RCI, but melatonin administration at postreperfusion hour 0 or 1 reversed I/R-induced reductions in the RCI. In contrast, melatonin administration at postreperfusion hours 3–12 had no protective effect. Histological analysis revealed a decrease in the ratio of normal to whole pyramidal cell number in the CA1 and CA3 regions in the I/R group. While melatonin administration within 3 h protected against degeneration, administration 6 h after reperfusion failed to protect. Conclusions: These results suggest that maternal administration of melatonin within 1 h after an ischemic/oxidative episode can prevent I/R-induced oxidative cerebral damage in neonatal rats.

Increased asymmetric dimethylarginine and enhanced inflammation are associated with impaired vascular reactivity in women with endometriosis

OBJECTIVEnEnhanced inflammatory responses which may inhibit vascular reactivity, are associated with endometriosis development. Asymmetric dimethylarginine (ADMA), an inhibitor of endogenous nitric oxide synthase, is also implicated in endothelial dysfunction. We aimed to determine whether plasma ADMA and systemic inflammation are associated with endothelial function in women with endometriosis.nnnMETHODSnWe evaluated 41 women with and 28 women without endometriosis. Plasma levels of lipids and inflammatory markers such as high sensitive-C reactive protein (hs-CRP), serum amyloid protein A (SAA), and interleukin-6 (IL-6) were measured in the two groups. We also measured levels of ADMA and symmetric dimethylarginine (SDMA). High-resolution ultrasonography measured flow-mediated vasodilation (FMD) to assess vasodilatory responses.nnnRESULTSnFMD was significantly lower in women with endometriosis compared to those without endometriosis (8.39 ± 0.43% vs 10.79 ± 0.54%, P = 0.001). While plasma lipid levels did not differ significantly between groups, levels of AMDA, but not SDMA, were significantly higher in women with endometriosis (409.7 ± 10.1 pmol/L vs 383.0 ± 48.3 pmol/L, P = 0.04). Inflammatory markers were also significantly higher in these women (hs-CRP: 1053.3 ± 252.0 ng/mL vs 272.0 ± 83.3 ng/mL, P = 0.02; SAA: 8.00 ± 1.53 μg/mL vs 3.82 ± 0.42 μg/mL, P = 0.04; IL-6: 2.73 ± 0.75 pg/mL vs 1.05 ± 0.60 pg/mL, P = 0.04). FMD was negatively correlated with plasma levels of ADMA (r = -0.37, P=0.01) and log hs-CRP (r = -0.34, P = 0.01).nnnCONCLUSIONnIncreased plasma ADMA levels and enhanced inflammation are associated with inhibited endothelial function in women with endometriosis.

Clear-cell adenocarcinoma of the uterine cervix in a 17-year-old adolescent

This report describes the case of the youngest Japanese person to be diagnosed with endocervical clearcell adenocarcinoma. In September 2005, a 17-year-old female adolescent visited a physician because of vaginal bleeding. A cervical tumor was discovered, and the patient was referred to our outpatient department. Vaginal examination showed a bleeding tumor approximately 1.5 cm in size protruding from the cervical os. The cytological finding of the uterine cervix was positive for malignancy, and the histological diagnosis by punch biopsy was clear-cell adenocarcinoma of the uterine cervix. A radical abdominal hysterectomy and pelvic lymphadenectomy were performed on October 30. Macroscopic findings showed a tumor, 1.5 cm in diameter, growing from the right side of the uterine cervix. The pathological diagnosis was clear-cell adenocarcinoma of the cervix (PT1b1NR0M0). The patient was discharged from our hospital without any adjuvant therapy. No signs of recurrence have been detected in the 2-year follow up.

Dexamethasone administration to the neonatal rat results in neurological dysfunction at the juvenile stage even at low doses

Dexamethasone (DEX), a synthetic glucocorticoid, has been widely used to prevent the development of a variety of poor health conditions in premature infants including chronic lung disease, inflammation, circulatory failure, and shock. Although there are some reports of neurologic complications related to DEX exposure, its full effects on the premature brain have not been examined in detail. To investigate the effects of DEX on neural development, we first administered low doses (0.2 mg/kg bodyweight or less) of the glucocorticoid to neonatal rats on a daily basis during the first postnatal week and examined subsequent behavioral alterations at the juvenile stage. DEX-treated rats exhibited not only a significant reduction in both somatic and brain weights but also learning disabilities as revealed in the shuttle avoidance test. The hippocampi of DEX-treated rats displayed a high apoptotic and a low mitotic cell density compared to control rats on day 7 after birth. In a subsequent experiment, neural stem/progenitor cells were cultured in the presence of DEX for 6 days. The glucocorticoid inhibited cell growth without an increase in cell death. These results suggest that administration of DEX to premature infants induces neurological dysfunction via inhibition of the proliferation of neural stem/progenitor cells.

Increased oxidant generation in the metabolism of hypoxanthine to uric acid and endothelial dysfunction in early-onset and late-onset preeclamptic women

Objective: The purpose of this study was to evaluate the association of vascular endothelial dysfunction with increased oxidant generation in the metabolism of hypoxanthine to uric acid in early-onset compared to late-onset preeclampsia. Methods: We investigated 12 women with early-onset preeclampsia, 14 women with late-onset preeclampsia, and 20 women with uncomplicated pregnancies. We measured serum derivatives of reactive oxygen metabolites (d-ROMs) as a marker of oxygen free radicals, serum biological antioxidant potential (BAP), hypoxanthine, uric acid, uric acid clearance (CUA), and flow-mediated vasodilation (FMD) as a marker of endothelial function in preeclamptic women. Results: Concentration of d-ROMs was significantly higher in both preeclamptic groups compared to the control group. Plasma levels of uric acid were significantly elevated in both preeclamptic groups compared to the control group. Plasma levels of hypoxanthine were significantly higher in early-onset preeclamptic women compared to controls, but not in late-onset preeclamptic women. CUA was significantly lower in late-onset preeclamptic women compared to controls, but not in early-onset preeclamptic women. The concentrations of hypoxanthine and uric acid correlated positively with the concentration of d-ROMs in all pregnant women. FMD was significantly lower in both preeclamptic groups compared with controls, but FMD in the early-onset preeclamptic group was significantly lower than in the late-onset preeclamptic group. Conclusions: We found that increased oxidant generation during metabolism of hypoxanthine to uric acid may impair endothelial function in early-onset preeclampsia.