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T Yanaihara

Publications and source records attributed to T Yanaihara.

At least 19 recordsLinked to original sources
PubMed2000

Effect of interleukin-1beta on aromatase activity and cell proliferation in human osteoblast-like cells (HOS).

Osteoblast cells have a capacity to produce estrogen from androgen. It is known that inflammatory cytokines in bone increase during estrogen deficiency. In the present study, the effect of interleukin-1beta (IL-1beta) on aromatase (Arom) activity in human osteoblast-like cells (HOS) was investigated. We also investigated the effect of IL-1beta and estradiol (E2) on cell proliferation in HOS. [(3)H] water method was employed to measure Arom activity. Expression of Arom mRNA was determined by the reverse-transcription polymerase chain reaction (RT-PCR) method. The PCR products were confirmed by Southern blot analysis. Cell proliferation was measured by an ELISA-bromo deoxyuridine (BrdU) kit. Addition of IL-1beta increased Arom activity in a dose-dependent manner and addition of IL-1beta (10 ng/ml) resulted in 40% greater activity than control. Addition of 500 ng/ml of human recombinant IL-1 receptor antagonist neutralized the increased Arom activity to control level. Stimulation of Arom mRNA expression by IL-1beta was also found. IL-1beta and E2 stimulate osteoblastic cell proliferation significantly. These findings suggest for the first time that IL-1beta stimulates Arom activity through the IL-1 receptor and also cell proliferation in osteoblast-like cells. It is also demonstrated that this stimulatory effect may be through the IL-1 receptor. Cell proliferation stimulated by IL-1beta was reduced by the addition of the Arom inhibitor fadrozole-HCL (CGS-16949A). These results imply that IL-1beta has a stimulatory effect on estrogen formation and sequentially cell proliferation in bone, and this mechanism may play an important role in osteoblastic function especially in postmenopausal women.

Aromatase↗
PubMed2000

Cell proliferation effect of lactoferrin in human endometrial stroma cells.

The aim of this study was to evaluate the effect of lactoferrin (LF) on the proliferation of human endometrial stroma cells. In addition, we compared the effect of LF, oestradiol and epidermal growth factor (EGF) on the proliferation of human endometrial stroma cells. Human endometrial tissue was obtained from patients with a normal menstrual cycle in the proliferative phase and the stroma cells were isolated and cultured in vitro. When LF was added to the culture medium, the rate of cell proliferation increased significantly in comparison to controls (P < 0.01). The enhanced rate of proliferation induced by LF was neutralized by the addition of anti-LF monoclonal antibody. The effect of LF on cell proliferation at a concentration of 100 ng/ml was similar to that of 10 nmol/l oestradiol, but less than that of 10 mg/ml EGF. When LF was added in combination with either oestradiol or EGF, no additive effects on cell proliferation were observed. Based on the present results, it is suggested that LF has a potential biological effect in the proliferation of human endometrium.

Cell Division↗
PubMed1999

The effect of vaginal delivery on the pelvic floor.

This study was undertaken to determine the effects of vaginal deliveries on anorectal function, and to analyze the possible clinical, physiological, and radiological risk factors predisposing to damage of the pelvic floor musculature. We studied 25 consecutive women with a mean age of 32 years old, 3 months after vaginal delivery, 17 of whom were primiparae and 8, multiparae. The symptoms of anal incontinence were assessed, and anorectal manometry, rectal sensation, and radiological measurements of the anorectal angle and pelvic floor position at rest, on squeezing, and on straining were performed. As a control, six nulliparous women underwent the same examinations. Pelvic floor descent in both the primiparae and multiparae was significantly greater at rest and on squeezing than that in the nulliparous women. Furthermore, pelvic floor descent on straining was greater in the multiparae than in the nulliparous women (P = 0.028). An analysis of the 17 primiparae showed that prolonged duration of the second stage of labor and third-degree perineal tears were important factors predisposing to pelvic floor descent. In fact, 3 of the 17 primiparae (17%) had anal incontinence. These findings indicate that vaginal delivery may cause pelvic floor descent, an obtuse anorectal angle, and bowel symptoms.

Adult↗
PubMed1999

The effect of cytokines on parathyroid hormone-related protein (PTH-rP) production in human amnion cells.

In the present study, the effects of various cytokines on parathyroid hormone-related protein (PTH-rP) production and PTH-rP mRNA expression in human amnion cells were studied. Immunoreactive (ir) PTH-rP was measured by immunoradiometric assay and the expression of PTH-rP mRNA was determined by Northern blot analysis. The addition of interleukin-1beta (IL-1beta, 10 ng/ml) and IL-6 (10 ng/ml) in culture medium for 24 hours resulted in a significant increase in ir-PTH-rP levels by 1.5 and 1.6 fold, respectively. The effects of these agents were dose dependent. In contrast, IL-2 (10 ng/ml) and IL-8 (10 ng/ml) showed no effect on the production of ir-PTH-rP from amnion cells. Treatment with IL-1beta or IL-6 for 6 hours increased the expression of PTH-rP mRNA in amnion cells. The stimulatory effect of IL-1beta was reduced by IL-1 receptor antagonist (IL-1Ra) in a dose dependent manner. Both tetradecanoyl phorbol acetate (TPA), and forskolin increased PTH-rP mRNA levels and the PTH-rP production in amnion cells, and the effect of TPA was much greater than that of forskolin. The findings of the present study suggest of the participation of inflammatory cytokines for the regulation of PTH-rP production in human amnion cells.

Amnion↗
PubMed1998

Lactoferrin and interleukin-6 interaction in amniotic infection.

Lactoferrin (Lf) has been found in most biological fluids including amniotic fluid and cervical mucoids in pregnant women, and released from neutrophils in response to the inflammation. As Lf possesses antimicrobial properties, it is widely considered to be an important component of the host defence against microbial infections. It is known that premature labor is caused by amniotic infection with the increase of prostaglandin production. High concentration of the inflammatory cytokines: interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) in the amniotic fluid has been known. However, changes of Lf in amniotic fluid with infection has not been reported. In the present study, Lf concentrations in amniotic fluid were measured under the intra-uterine infections state and the biological significance of Lf was investigated. The effects of Lf on the IL-6 and IL-6mRNA production in cultured amnion cells were also investigated. The concentrations of Lf and IL-6 in amniotic fluid with CAM were 8.76 +/- 0.65 micrograms/ml and 6.92 +/- 4.88 ng/ml (n = 28) respectively and both were significantly higher (p < 0.01) than those without CAM [0.86 +/- 0.81 microgram/ml and 0.34 +/- 0.25 ng/ml (n = 31)]. Significant positive correlation (r = 0.91, p < 0.01) between Lf and IL-6 levels in amniotic fluid was found. IL-6 production induced by lipopolysaccharide (LPS) (100 ng/ml) in cultured amnion cells was significantly inhibited (p < 0.05) under the physiological concentration of Lf in amnion. Total RNA was extracted from the amniotic cells by guianizine solution. RT-PCR procedure and product analysis were performed from one microgram aliquote of total RNA. beta-actin was used as an international standard and c-DNA samples were followed by 30 cycles of PCR. RT-PCR product of IL-6 mRNA was detected by Southern hybridization. Expression of IL-6 mRNA was inhibited by the addition of Lf. From the results, the possibility that Lf might suppress amniotic IL-6 production under the condition of amniotic infection is suggested. It is also suggested that Lf might act as self defence mechanism from intra-uterine infection.

Amnion↗
PubMed1998

Analysis of HLA-DQ alpha sequences for prenatal diagnosis in single fetal cells from maternal blood.

We have extended a previously developed method that allows prenatal DNA diagnosis of female fetuses through the isolation of single nucleated erythrocytes from maternal blood by developing a method that can distinguish between maternal and fetal nucleated erythrocytes. Nucleated erythrocytes were separated by a density-gradient method and then collected by micromanipulation. Sex was determined after primer extension preamplification (PEP) of the entire genome of a single cell, and human leukocyte antigen (HLA)-DQ alpha type was determined after further amplification of this gene. The HLA-DQ alpha genotype of fetal erythrocytes in maternal blood samples and their corresponding paternal and maternal lymphocytes were successfully determined in all cases. The accuracy of the method was determined by using single nucleated erythrocytes from umbilical cord blood from five normal deliveries. This is the first demonstration that the fetal HLA-DQ alpha gene sequences can be identified in a small aliquot of a single nucleated erythrocyte in maternal blood. We believe that this method ushers in a new era in which the reliability and accuracy of noninvasive prenatal DNA diagnosis from maternal blood is markedly improved.

Alleles↗
PubMed1998

Prenatal diagnosis of ornithine transcarbamylase deficiency by using a single nucleated erythrocyte from maternal blood.

We have developed a method that allows the prenatal DNA diagnosis of ornithine transcarbamylase (OTC) deficiency by using a single fetal nucleated erythrocyte (NRBC) isolated from maternal blood. OTC gene analysis of a male patient (TF) with early onset OTC deficiency was performed by single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing. To investigate the possible prenatal diagnosis of OTC deficiency, maternal blood was obtained at 13 weeks of gestation of a subsequent pregnancy, from the mother of patient TF. NRBCs in the maternal blood were separated by using the density gradient method and then collected with a micromanipulator. The entire genome of a single NRBC was amplified by primer extension preamplification (PEP). The human leukocyte antigen (HLA)-DQ alpha genotype and sex were determined from small aliquots of the PEP product. The HLA-DQ alpha genotype of each of the parents of the male patient was also determined. Once a single NRBC had been identified as being of fetal origin, the OTC gene was analyzed by using the restriction fragment length polymorphism (RFLP) method. DNA analysis revealed a point mutation in exon 9 of the OTC gene in the OTC-deficient patient (TF). All NRBCs retrieved from maternal blood were successfully identified as being of fetal origin by HLA-DQ alpha genotyping and sex determination. RFLP analysis demonstrated that the fetal OTC gene was normal. This is the first study to successfully diagnose OTC deficiency prenatally, by using a single fetal NRBC from the maternal circulation. Such prenatal DNA diagnosis is non-invasive and can be applied to other genetic diseases, including autosomal and X-linked diseases.

Erythrocytes↗
PubMed1998

Inhibitory effects of catecholamines and maternal stress on aromatase activity in the fetal rat brain.

OBJECTIVE: Aromatization in the the fetal brain is thought to be involved both in sex differentiation during early development and in adult sexual behavior. Although recently the relationship between aromatase and catecholamine has been discussed, the effect of stress on aromatase in the fetal brain has not been clarified. Therefore, in the present study, localization of aromatase and the inhibitory effects of catecholamines and maternal stress on aromatase activity in the fetal rat brain were examined. METHODS: Localization of aromatase cytochrome P-450 using a specific polyclonal antiserum against human placenta aromatase was examined, and the inhibitory effects of dopamine and norepinephrine on aromatase activity in vitro were studied. Further, the influences of intrauterine stress on aromatase activity in the prenatal rat brain were evaluated in vivo. RESULTS: Aromatase-immunoreactive neurons are located principally in the medial amygdaloid nucleus. Aromatase activity in the fetal rat brain was competitively inhibited by dopamine and norepinephrine, with Ki values of 120 microM and 100 microM, respectively. Aromatase activity in the fetal brain was significantly lower in stressed rats given 1.5% salt water (89.2 +/- 17.5 fmol/mg/hr; n = 4) (p < 0.05) than in the control group (123.1 +/- 10.0 fmol/mg/hr; n = 4). CONCLUSION: Aromatase activity in the prenatal rat brain is influenced by catecholamine metabolism during intrauterine stress.

Amygdala↗
PubMed1997

Steroid sulfatase activity in osteoblast cells.

We have demonstrated steroid sulfatase activity in osteoblast cells and characteristics of the enzyme were also investigated. Cell free homogenate of rat osteoblast cell line, UMR106-01 and human osteoblast cell lines, MG-63, HOS were incubated with [3H] dehydroepiandrosterone-sulfate (DHEA-sulfate) or [3H] estrone-sulfate (E1-sulfate). The formation of DHEA or E1 from the corresponding substrate was identified by crystallization to constant specific activity. Michaelis constant (K(m)) for DHEA-sulfate was estimated as 2.1 x 10(-8)M in UMR106-01, 7.4 x 10(-7)M in MG-63, 5.8 x 10(-7)M in HOS and that for E1-sulfate was 4.1 x 10(-7)M, 3.0 x 10(-7)M, 9.8 x 10(-7)M, respectively. The expression of steroid sulfatase messenger ribonucleic acid in human osteoblast cells, HOS and MG-63 was first demonstrated by reverse transcription-polymerase chain reaction. The existence of steroid sulfatase in human and rat osteoblast cells suggests that osteoblast cells have the capacity to convert circulating sulfo-conjugated steroids to more active androgens and estrogens. This may indicate an important role of bone in facilitating hormonal action.

Animals↗
PubMed1997

A study of gamma-aminobutyric acid (GABA) in amniotic fluid.

OBJECTIVE: The purpose of the study was to evaluate the role of gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, in amniotic fluid (AF) during fetal distress, because it has been reported that several neurotransmitters, e.g. norepinephrine, are affected by GABA. METHODS: AF was obtained during elective cesarean section (CS, n = 11) and cesarean section due to fetal distress without labor pain (FD, n = 7). Maternal and umbilical-cord blood, as well as the first urine of the neonates, also were collected. GABA, norepinephrine (NE), and epinephrine (EP) concentrations were measured using HPLC. RESULTS: The GABA concentration was higher in the AF than in either maternal or fetal circulation, or in the first urine of neonates. The GABA concentrations in the AF and in the first urine of neonates were significantly higher in the FD group than in the CS group (p < 0.05). Furthermore, significant positive correlations were observed between the NE and GABA concentrations and between the EP and GABA concentrations in the AF. GABA was produced in a time-dependent manner in cultured amnion cells. CONCLUSION: The highest concentration of GABA was found in the AF. The GABA in the AF appeared to be derived from both the amniotic membrane and the fetal urine. The increase in the GABA concentration in cases of fetal distress might be partially derived from the fetus via fetal urine. The positive correlations between the concentrations of GABA and those of NE and EP in the AF, suggest that GABA, NE, and EP might play important roles during fetal distress.

Adrenergic alpha-Agonists↗
PubMed1997

3Beta-hydroxysteroid dehydrogenase activity in human osteoblast-like cells.

This paper describes for the first time the presence of 3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity in osteoblast-like cells and investigates its characteristics. 3beta-HSD activity was detected by the formation of androstenedione from [3H]dehydroepiandrosterone (DHEA) in whole cell assays of human osteoblast-like cells, HOS and MG-63. The radiolabeled product, androstenedione, was purified by thin-layer chromatography and identified by recrystallization on admixture with authentic androstenedione to show constant specific activities. The apparent Michaelis constant (Km) for DHEA in HOS was found to be 9.9 microM and that in MG-63 was 80.4 microM. The expression of the 3beta-HSD messenger ribonucleic acid in HOS and MG-63 was demonstrated through a reverse transcription-polymerase chain reaction. The PCR products were confirmed by Southern blot analysis. The existence of 3beta-HSD in osteoblast-like cells indicates that these cells convert delta5 androgens into more biologically active delta4 3-keto steroids. These results, together with the demonstration of other steroid converting enzyme systems, suggest that the osteoblast cells play an important role in facilitating hormonal action in bone tissue.

3-Hydroxysteroid Dehydrogenases↗
PubMed1997

[Gonadal dysfunction].

Function of hypothalamic-pituitary-ovarian axis is an essential factor for the maintenance of regular cycles in mature women. The disturbance of function of those organs causes gonadal dysfunction such as anovulation, amenorrhea and menstrual disorders. Therefore, the correct diagnosis for the assessment of CNS and ovarian function is clinically important to treat the patients those who have an menstrual disorders. In this review, the mechanism of normal gonadal cycles and the diagnostic method and the treatment of gonadal dysfunction are described.

Amenorrhea↗