Rapid accumulation of deleted mitochondrial deoxyribonucleic acid in postmenopausal ovaries

To study the aging process in human ovary, we analyzed the accumulation of mitochondrial DNA (mtDNA) mutation in ovary in women of various ages. Thirty-nine tissues from ovaries and abdominal muscles, ranging from those of a fetus to those of a 77-yr-old woman, were collected at artificial abortion or gynecological surgery. Total DNA was extracted from these tissues, and parts of mtDNA were amplified via polymerase chain reaction. Through these experiments, we found a 4977-bp deletion of mtDNA between the ATPase8 and ND5 genes in ovarian samples obtained from menopausal and postmenopausal women and in all muscle samples. Quantitative analysis of the deleted mtDNA also showed that the accumulation of deleted mtDNA in the ovary occurs rapidly around the menopausal period while the accumulation found in abdominal muscle occurs gradually with aging. These results indicated that the mtDNA deletion occurs in muscular tissues even at very young ages but that accumulation of the deletion in ovarian tissue starts at the menopausal period and may have a relationship to dysfunction of the ovary in aging.

Plasma angiotensin I concentration and serum placental leucine aminopeptidase (P-LAP) activities in puerperal hypertension

To elucidate the involvement of angiotensin in puerperal hypertension with and without preeclampsia in the course of prior pregnancy, we measured plasma angiotensin I levels and serum placental leucine aminopeptidase (P-LAP) activities in several puerperal hypertensive patients. Placental leucine aminopeptidase (P-LAP) activities of puerperal hypertensive patients with severe preeclampsia during prior pregnancy were equal to or somewhat lower levels than those in normal puerperal women after a normal pregnancy. However, their angiotensin I levels were higher than those in normal puerperal women after a normal pregnancy. In puerperal hypertensive patients with and without preeclampsia during prior pregnancy, P-LAP activities tended to show much lower levels that those in normal puerperal women, while angiotensin I levels tended to show much higher levels than those in normal puerperal women, respectively. Since serum placental leucine aminopeptidase acts as an angiotensinase via degradation of angiotensin III (A-III), our present data suggest the involvement of angiotensin in puerperal hypertension.

[Descriptive epidemiology of malignant neoplasm of the ovary in Japan]

Descriptive-epidemiological analysis of national mortality statistics on malignant neoplasm of the ovary revealed the following major findings. 1. Crude and age-adjusted mortality rates have gradually and constantly increased from 1947 to 1990 by 8.8 times and 5.4 times, respectively. 2. This increasing mortality trend was concluded to be mainly ascribable to the increasing rate of incidence rate and more accurate diagnosis. Eight background factors are generally considered to be determinants of the mortality trend. 3. Individual effects of age, year and birth cohort on mortality were analyzed and found to be constant after 50 years of age, uniformly increasing in 1950-1990, and clearly decreasing in cohorts born after 1931-1935. 4. A high standardized mortality ratio was detected in prefectures with large cities and in the northern part of Japan, with significant geographical clustering of the low standardized mortality ratio in the southern part, particularly in Kyushu Island. 5. The incidence rate of ovarian cancer was found to be relatively low in Japan as compared to the developed countries in Europe and the U.S.A..

Potentiating effect of amphotericin B on five platinum anticancer drugs in human cis-diamminedichloroplatinum (II) sensitive and resistant ovarian carcinoma cells

We have determined an effect of amphotericin B (AMB), an antifungal drug, on the cytotoxicity of cis-diamminedichloro-platinum (II) (CDDP) and 4 CDDP analogues in a human ovarian carcinoma cell line (NOS2). Intracellular accumulation of CDDP was elevated significantly by treatment with AMB, and AMB significantly potentiated the cytotoxicity of CDDP by MTT assay. Intracellular accumulation of 4 CDDP analogues was also elevated by the treatment with AMB and the order of increasing accumulation rate of platinum drugs was consistent with that of dose modification factor (DMF). AMB also increased the intracellular CDDP accumulation in CDDP resistant cells (NOS2CR), derived from NOS2. The intracellular accumulations of 4 CDDP analogues were elevated slightly by the treatment with AMB in NOS2CR cells. DMFs of 5 platinum drugs in NOS2CR cells, however, were more than those in NOS2 cells. These results indicate that AMB sensitizes NOS2 and NOS2CR cells to platinum drugs, partially due to the increasing intracellular accumulation of these drugs. In addition, CDDP analogues are more effective in NOS2CR cells than CDDP, but the cytotoxicity of CDDP was most potentiated by AMB among the 5 platinum drugs under study.

Poly (adenosine diphosphate-ribose) synthesis in the anterior pituitary of the female rat throughout the estrous cycle: study of possible relation to cell proliferation and prolactin gene expression

To investigate whether cell proliferation and PRL gene expression in female rat pituitary during estrous cycle were mediated by the poly (ADP)-ribosylation of chromatin proteins, anterior pituitaries at different estrous cycle were obtained from female Wistar rats, and poly (ADP-ribose) synthesis, DNA synthesis, PRL and GH messenger RNAs and PRL content in the pituitary, and serum concentrations of PRL and estradiol were analyzed. From diestrus to proestrus, poly (ADP-ribose) synthesis, the contents of PRL messenger RNA and PRL in the pituitary increased significantly, and decreased at estrus. However, DNA synthesis and serum concentration of PRL showed a significant increase from proestrus to estrus. Serum estradiol concentration increased from diestrus to proestrus. No significant change was observed in the pituitary GH messenger RNA content during estrous cycle. The increase of PRL messenger RNA from diestrus to proestrus was abolished completely by the administration of nicotinamide, an inhibitor of poly (ADP-ribose) synthesis, to rats at diestrus. These results indicate that poly (ADP)-ribosylation of chromatin proteins may play some role in cell proliferation and transcription of PRL gene during rat estrous cycle.

Detection of human papillomaviruses from histologically normal lymph nodes of Japanese cervical cancer patients by nested polymerase chain-reaction assay

To determine the prognostic significance of human papilloma virus (HPV) DNA in histologically normal lymph nodes, we developed a nested polymerase chain-reaction (PCR) method on HPV16,18 and 33 DNAs for formalin-fixed, paraffin-embedded tissues. We investigated 370 histologically normal lymph nodes from 15 patients treated for stage-IB/IIB (FIGO) invasive cervical cancer. HPV16 DNA was detected in 7 (47%) and HPV18 DNA in 3 (20%) of the cervical cancers. Examination of histologically normal lymph nodes from these 10 patients by nested PCR revealed HPV DNA in 5 (50%) of them; in all cases HPV type in lymph nodes and tumor was the same. Two of these 5 patients had a recurrence (pelvic cavity or lung) and died of cancer, although all 5 had had pelvic radiotherapy after radical hysterectomy and lymphadenectomy. These findings indicate that nested PCR is useful for evaluating early lymph-node involvement retrospectively in HPV-positive cases.

Pregnancy and successful delivery in a patient with triple heart valve prosthesis

A 42-year-old patient had a history of rheumatic fever in childhood. At 37 years of age, she underwent a triple heart valve replacement; thereafter, she was followed with the administration of warfarin and methyldigoxin. Her third pregnancy occurred with the last menstruation on 12 March 1990. At the 30th gestational week, she was admitted to the Nagoya University Hospital for the control of anticoagulation and rest. She delivered by cesarean section a healthy male infant weighing 2070 g at 34 weeks of gestation. The post-operative course was uneventful. This report shows that a patient with a three heart valve prosthesis tolerated pregnancy well under intense medical supervision.

Enhanced proliferation of fetal rat hepatocytes in primary culture induced by ritodrine

OBJECTIVE

Although ritodrine crosses the placenta, its direct effect on fetal cell proliferation has not been reported. We hypothesized that beta 2-adrenergic receptor stimulation could promote fetal liver growth.

STUDY DESIGN

Ritodrine was added to serum- and hormone-free primary cultures of fetal, neonatal, or adult rat hepatocytes. We measured both tritiated thymidine incorporation into deoxyribonucleic acid and nucleus number. The effect of ritodrine on cell cycle was also analyzed with flow cytometry.

RESULTS

Ritodrine enhanced the proliferation of fetal rat hepatocytes. Ritodrine remarkably stimulated deoxyribonucleic acid synthesis of fetal and neonatal but not adult hepatocytes. The effect was dose dependent and was antagonized by propranolol. Analysis of the nuclear deoxyribonucleic acid content derived from flow cytometry revealed that cells stimulated by ritodrine entered S phase.

CONCLUSION

These results indicate that ritodrine may promote the proliferation of fetal hepatocytes through the stimulation of beta 2-adrenergic receptors, followed by induction of deoxyribonucleic acid synthesis.

Development of postmolar trophoblastic disease after partial molar pregnancy

We investigated the clinical characteristics of patients with partial molar pregnancy and patients who developed invasive partial mole. Between 1981 and 1990, 349 patients were followed up by the Aichi prefecture trophoblastic disease registration center after partial molar pregnancy. Ten of the 349 patients with partial molar pregnancy developed invasive partial mole, an incidence (2.87%) significantly lower (P < 0.01) than that for the development of invasive complete mole (174/1410, 12.34%) following complete molar pregnancy during the same period. None of the patients had any histologic evidence of choriocarcinoma after partial molar pregnancy. The medical records of these 10 patients were compared with those of 85 of 174 registered patients with invasive complete mole, whose clinical information could be used. The interval from molar delivery to the diagnosis of invasive mole was under 9 weeks (mean, 4.90 weeks) for the patients with invasive partial mole and was significantly shorter than that for the patients with invasive complete mole, from 2 to 18 weeks (mean, 8.12 weeks) (P < 0.01). All 10 patients with invasive partial mole achieved a negative hCG level (< 0.5 mIU/ml) with eight courses or less of chemotherapy (mean, 5.50 courses). The number of courses was the same as that in the invasive complete mole group (mean, 5.70 courses). None of the patients with invasive partial mole developed recurrence. We conclude that all patients with partial molar pregnancy should be followed up as are those with complete molar pregnancy. Some patients with partial molar pregnancy will develop invasive partial mole with a relatively short interval, but remission can be achieved without the recurrence and choriocarcinoma seldom develops after partial molar pregnancy.

Randomised study of immunotherapy with OK-432 in uterine cervical carcinoma

OK-432, a streptococcal preparation, was administered to patients with stage Ib and II cervical carcinoma except for adeno- and adenosquamous carcinomas. To evaluate the efficacy of OK-432 precisely, 177 patients were stratified by clinical stage, radiotherapy, and lymph node metastasis after complete radical hysterectomy and pelvic lymphadenectomy. Within each stratum, patients were divided randomly into OK-432 and control groups. 85 patients received OK-432 and 92 patients did not. No significant difference was observed in overall 5-year disease free rates between the OK-432 and the control groups, although the mean diameter of erythema on SU-polysaccharide (SU-PS) skin test was larger in the OK-432 group than in the control group. In stage IIb, a significant difference was observed between the OK-432 and control groups. This difference, however, could be attributed in part to the different incidence of the lymph node metastasis. In stage II without lymph node metastasis, 5-year disease free rate was significantly higher in the OK-432 group.

Human ovarian aging and mitochondrial DNA deletion

The functions of human ovary change dynamically around the menopausal period. A decrease of the number of primordial follicles and an increase of fibrous tissues are observed histologically in the aged ovary. As endocrinological aspects at menopause, the synthesis and secretion of ovarian steroid hormones such as estrogens and progesterone decrease, followed with the resultant increases of pituitary gonadotropins. However, the mechanism of menopause and ovarian aging is not well understood. Thus, to study the regulatory mechanism of ovarian dysfunction by aging, we analyzed the accumulation of mitochondrial DNA (mtDNA) mutation in the human ovary in women of various ages. The amplification of a 5.5-kb region in mtDNA with polymerase chain reaction revealed a 0.5-kb band in ovarian samples obtained from menopausal and postmenopausal women, which means that the 5.0-kb deletion of mtDNA in ovarian tissue starts at the menopausal period. The close relationship between the occurrence of ovarian mtDNA deletion and the menstrual irregularity was also observed. These observations suggest that the accumulation of the deleted mtDNA may be a regulating factor of dysfunction of the ovary by aging.

Source of prolactin in human follicular fluid

To analyze whether prolactin (PRL) in human follicular fluid (FF) is synthesized locally or derived from the circulation, PRL concentrations of plasma and FF were determined in the patients after ovarian stimulations. The amounts of PRL messenger ribonucleic acid (mRNA) in the follicular tissues during different menstrual phases were also determined. The FF PRL concentration was correlated positively with plasma PRL and highest estradiol levels during the stimulatory cycle. No PRL mRNA sequence was detected in the RNAs extracted from follicles at any stage in the menstrual cycle, although beta-actin mRNA was detected in all samples. In a comparison with pituitary RNA, the PRL mRNA concentration in ovarian follicular tissues seemed to be 10,000 times less than that in the pituitary. These results suggest that FF PRL may not be synthesized locally, but derived from the pituitary via the circulation through passive diffusion, and thus regulated by estrogen.

Gonadotropin induces expression of c-fos and c-jun genes in rat ovaries

It has been shown that the expression of protooncogenes, c-fos and c-jun, induced by growth factors and hormones plays important roles in cellular proliferation, tissue differentiation and transcription of certain genes. Since gonadotropin stimulates ovarian steroidogenesis and cellular proliferation, we investigated whether gonadotropin affects the expression of c-fos and c-jun genes in rat ovaries. The expression of mRNA coding side chain cleavage enzyme (P450scc), the rate limiting enzyme in ovarian steroidogenesis was also studied. The effect of gonadotropin was examined in female rats whose gonadotrophs were medically ablated by GnRH agonist (TAP-144-SR). After intravenous administration of pregnant mare's serum gonadotropin (PMSG:30 IU/rat), their ovaries were dissected out at various time intervals and total RNA was extracted. Changes in the levels of c-fos, c-jun and P450scc mRNAs were determined by Northern blot analysis. The levels of c-fos and c-jun mRNAs increased rapidly and transiently with the peak levels at 15 min after PMSG administration. The levels of both mRNAs were decreased by 30 to 60 min. On the other hand, the levels of P450scc mRNA started to increase 60 min after PMSG. These results indicate that gonadotropin-induced increase in the expression of c-fos and c-jun genes may play important roles in mediating the action of gonadotropin on the ovaries.

[Effect of chemotherapy on the prognosis of ovarian cancer]

Through the collaboration of 22 institutions nationwide, a total of 1,185 cases of ovarian cancer treated between January, 1980 and December, 1987, were investigated as to their prognosis from the aspect of the chemotherapeutic effect. (1) An excellent effect of the remission-induction chemotherapy was observed in a group receiving combination therapy with CDDP as the main ingredient. In particular a significant effect was seen in stages III and IV. In addition, the effect on the remaining tumors by diameter also showed a significant difference in cases of tumors of not less than 2 cm in diameter. (2) As to the effect on histological types, a comparison in stage III showed a favourable effect on endometroid, serous and mucinous adenocarcinomas, while no effect was observed in clear cell adenocarcinoma. (3) The effect of the remission induction chemotherapy did not always give rise to an improvement in the long-term prognosis of ovarian cancer, and the establishment of a therapeutic method aimed at the prevention of recurrence was desired. (4) To improve the long-term prognosis, intermittent (or cyclic) chemotherapy with CDDP as the main ingredient was found to be very effective, but maintenance chemotherapy with orally administered of 5-Fluorouracil or Tegaful was not effective. (5) The effect of the conventional immunotherapy was not observed at all.

Prophylactic effect of bestatin on the onset of invasive mole--clinical and fundamental studies

This study was performed to determine whether bestatin (Ubenimex) has clinical prophylactic effects on the onset of invasive mole and a direct inhibitory effect on the growth of hydatidiform molar cells. A total of 49 patients with hydatidiform mole treated at Nagoya University Hospital from 1984 to 1990 were randomly divided into two groups, a bestatin administered-group and a bestatin non-administered group. Patients in the bestatin group were given 30 mg of bestatin orally and daily for three months just after their molar deliveries. There was no significant difference in age, gravidity, parity and gestational weeks between the two groups. There was also no significant difference in the duration of human chorionic gonadotropin (hCG) negative conversion in patients without invasive mole between the two groups. However, the incidence of invasive mole in the bestatin group (2/25, 8%) was significantly lower than that of the non-bestatin group (7/24, 29.2%). Nevertheless, there was no significant difference between the two groups in such immunological parameters as PHA skin test, PPD skin test, PHA stimulation index (PHA-SI), white blood cell (WBC) count lymphocytes % per WBC, OKT 3% per lymphocytes, OKT 4% per lymphocytes, OKT4/OKT8 and Leu 11% per lymphocytes. In vitro studies were performed with primary cultured hydatidiform moles. The result was that bestatin inhibited the secretion of hCG and 3H-thymidine uptake of hydatidiform molar cells. Thus, a possibility was suggested that bestatin directly inhibits the growth of hydatidiform molar cells and prevents the onset of invasive mole.

Rapid determination of fetal sex using amniotic fluid cells and the polymerase chain reaction

We determined the sex of 50 fetuses by an amplification of the Y-chromosome specific fragment using the polymerase chain reaction (PCR). Amniotic fluid cells were collected by amniocentesis from pregnant women at 14 to 17 weeks of gestation. Total DNA was purified from cells in 1 ml of amniotic fluid. When only the expected 130 base pair X-chromosome specific fragment was detected, we identified the fetus as female, while when both the expected 170 base pair Y-chromosome specific and X-chromosome specific fragments were detected, we identified it as male. In all cases, identification was confirmed either by chromosome analysis or post partum.

Relationship between the changes in placental blood flow resistance assessed by Doppler technique and maternal serum placental aminopeptidases, which degrade vaso-active peptides, in pre-eclampsia

Our study showed that there were statistically significant correlations between the systolic and diastolic ratio (S/D) of maternal uterine or umbilical artery and the levels of maternal serum aminopeptidase activities in pre-eclampsia. Kininase I was positively correlated with the S/D ratios, whereas placental leucine aminopeptidase (P-LAP) and aminopeptidase A were negatively correlated with the S/D ratios. It is known that the increased S/D ratios reflect the increased utero-placental blood flow resistance. Since our previous study showed that placental aminopeptidases degrade vasoactive peptides such as oxytocin, angiotensin and bradykinin, which the fetus actively produces, our present study suggests that the increased vascular resistance in feto-placental circulation in pre-eclampsia is partly controlled by changes in vaso-active peptides, via degradation by placental aminopeptidases.

Further evaluation of the pregnancy-linked down-regulation of the paternal antigen-specific splenic cytotoxic T lymphocyte activity in allogeneically pregnant mice

Cytotoxic T lymphocyte (CTL) activity directed against paternal alloantigen was examined in allogeneically pregnant mice using various allogeneic combinations. The spleen cells from pregnant C57BL/6 (H-2b) mice mated with BALB/c (H-2d) male mice generated less anti-H-2d CTL after in vitro sensitization than those from unpregnant or syngeneically mated C57BL/6 mice. Different allogeneic combinations including the incompatibility at only D region of H-2 or minor histocompatibility loci were effective for downregulating the anti-paternal CTL activity in pregnancy. The downregulation of anti-paternal CTL activity induced by allogeneic pregnancy occurred at day 10 to day 18 of pregnancy, most extensively at day 14. The allogeneic pregnancy also downregulated the allogeneic CTL activities that had been amplified by injecting alloantigens before mating.

[A group study on prognosis of ovarian cancer in Japan]

An assessment has been made, with the cooperation of 22 institutes, of 1,185 cases of ovarian cancer as subjects who were treated in the period from January, 1980, to December, 1987. As a result, (1) As for distribution by clinical staging at the initial examination, the cases in Stage III were the most numerous, followed by those in Stage I, and if classified according to the histological type, serous cystadenocarcinoma was the most frequently observed in Stage III, and undifferentiated and unclassified carcinomata were observed in Stages III and IV. (2) In the examination of prognostic factors, it was confirmed that the clinical stage, histological type and diameter of the remaining tumor after the initial operation were important factors. (3) A significant difference was observed between the grade of histomorphological differentiation and prognosis, the difference was chiefly due to the deviated distribution of clinical staging in each group of differentiation. (4) A favorable trend was observed in the prognosis by patient's age toward the younger layer. (5) When the starting time of the therapy is considered, a trend toward improvement has been seen year by year, and it is considered that the beneficial effect of chemotherapy with CDDP contributes to this.

Degradation of oxytocin by the human placenta: effect of selective inhibitors

The hydrolysis of oxytocin by human placental subcellular fractions was studied in the presence of selective inhibitors by measuring liberated amino acids by high performance liquid chromatography (HPLC). Oxytocin degradation by microsomal and lysosomal fractions was inhibited by bestatin, amastatin and puromycin. The IC50 values of these inhibitors on oxytocin degradation by both fractions were similar to those of these inhibitors on the human placental aminopeptidase M measured by L-Leu-p-nitroanilide as a substrate (LAP activity), which we reported previously. However, purified aminopeptidase M from human placental microsomal fractions could not liberate any amino acid from oxytocin. Since phosphoramidon (1 μmol/l), a putative metalloendopeptidase inhibitor, and N-benzylcarbonyl-valyl-prolinal (Z-Val-prolinal) (14 μmol/l), a selective inhibitor of post-proline endopeptidase, could not significantly influence the degradation of oxytocin by either subcellular fractions, neither enzyme seems to be actively involved in oxytocin degradation. These results strongly suggested the existence of oxytocinase(s) other than the above three enzymes in microsomal and/or lysosomal fractions of human placenta.

The effect of nifedipine and dipyridamole on the Doppler blood flow waveforms of umbilical and uterine arteries in hypertensive pregnant women

In a study of 45 hypertensive pregnant women, the systolic velocity/diastolic velocity ratio and pulsatility index of the umbilical and uterine arteries showed good correlation with the maternal blood pressure, and they appeared to provide a good parameter for the fetoplacental condition. Using the pulse Doppler method, we studied the effects of the antihypertensive agent nifedipine and of dipyridamole (an agent used to treat proteinuria) on the blood flow of the umbilical and uterine arteries in 16 hypertensive pregnant women. The results proved that both drugs caused a decrease in the vascular resistance of the umbilical artery and suggested that they increased the blood flow volume of this artery and were useful in the treatment of hypertension during pregnancy.