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Yanase T, Maeda K, Kato T, Nyuta S, Kamata H, Yamakawa M, Tsuda T. The resurgence of Shamonda virus, an African Simbu group virus of the genus Orthobunyavirus, in Japan. Arch Virol 2004; 150:361-9. [PMID: 15503217 DOI: 10.1007/s00705-004-0419-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Accepted: 08/27/2004] [Indexed: 10/26/2022]
Abstract
Six virus isolations were made from Culicoides biting midges and blood samples of sentinel cattle in Kagoshima and Miyazaki Prefectures, the southern part of Japan, in 2002. Serological and genetical tests identified these viruses as isolates of Shamonda virus (SHAV), which belongs to the Simbu group of the genus Orthobunyavirus of the family Bunyaviridae. Initially, SHAV was isolated from cattle and Culicoides biting midges in Nigeria in the 1960s, and its presence has not been reported until this study. The present results indicate a wider distribution of SHAV than previously assumed.
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Nawata H, Shirasawa S, Nakashima N, Araki E, Hashiguchi J, Miyake S, Yamauchi T, Hamaguchi K, Yoshimatsu H, Takeda H, Fukushima H, Sasahara T, Yamaguchi K, Sonoda N, Sonoda T, Matsumoto M, Tanaka Y, Sugimoto H, Tsubouchi H, Inoguchi T, Yanase T, Wake N, Narazaki K, Eto T, Umeda F, Nakazaki M, Ono J, Asano T, Ito Y, Akazawa S, Hazegawa I, Takasu N, Shinohara M, Nishikawa T, Nagafuchi S, Okeda T, Eguchi K, Iwase M, Ishikawa M, Aoki M, Keicho N, Kato N, Yasuda K, Yamamoto K, Sasazuki T. Genome-wide linkage analysis of type 2 diabetes mellitus reconfirms the susceptibility locus on 11p13–p12 in Japanese. J Hum Genet 2004; 49:629-634. [PMID: 15490285 DOI: 10.1007/s10038-004-0199-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Accepted: 08/09/2004] [Indexed: 10/26/2022]
Abstract
Type 2 diabetes mellitus is a heterogeneous disorder, and the development of type 2 diabetes mellitus is associated with both insulin secretion defect and insulin resistance. The primary metabolic defect leading to type 2 diabetes mellitus has been thought to be varied among populations, especially in Japanese and Caucasians. Here, we have done the genome-wide scan for type 2 diabetes mellitus using 102 affected Japanese sib-pairs to identify the genetic factors predisposing to type 2 diabetes mellitus. Nonparametric linkage analysis showed one suggestive evidence for linkage to 11p13-p12 [D11S905: two-point maximum LOD score (MLS) of 2.89 and multipoint MLS of 2.32] and one nominally significant evidence for linkage to 6q15-q16 (D6S462: two-point MLS of 2.02). Interestingly, the 11p13-p12 region was reported to be a susceptibility locus for Japanese type 2 diabetes mellitus with suggestive evidence of linkage, and D11S905 was within 5 cM to D11S935 with the highest MLS in the previous linkage analysis reported. The only overlapped susceptibility region with suggestive evidence of linkage for Japanese type 2 diabetes mellitus was D11S935-D11S905 among the three reports including this study. These results taken together suggest that a susceptibility gene for type 2 diabetes mellitus in Japanese will reside in 11p13-p12.
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203
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Iwamoto T, Yanase T, Koh E, Horie H, Baba K, Namiki M, Nawata H. [Reference ranges of total serum and free testosterone in Japanese male adults]. Nihon Hinyokika Gakkai Zasshi 2004; 95:751-60. [PMID: 15508699 DOI: 10.5980/jpnjurol1989.95.751] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
PURPOSE To establish reference range of serum Total Testosterone (T-T) and Free Testosterone (F-T) in Japanese male adults. SUBJECTS AND METHOD Among 1,172 male adults, who daily lived their healthy life, 1,143 subjects in the year range from 20 to 77 years old, who had serum LH concentration within its reference range (For 20-70 years old: 1.1-25.9 mIU/mL), were selected. As diurnal rhythm of both T-T and F-T was observed, blood samples were collected in the morning when T-T and F-T concentration were relatively stable at their high concentration levels. The collected samples were stored at -20 degree C until they were used for assays. RESULTS Reference range for T-T has decided to express by the mean +/- 2SD calculated from the entire test results, because influence of aging on the results was negligible, Reference range of T-T has established as 2.01-7.50 ng/mL. The other hand, reference ranges of F-T classified for every decade have decided to express by the mean +/- 2SD of each decade subgroup, because great influence of aging on F-T was observed. For each decade from 20 years on and > 70 years, reference ranges of F-T have established as: 8.5-27.9 pg/mL, 7.6-23.1 pg/mL, 7.7-21.6 pg/mL, 6.9-18.4 pg/mL, 5.4-16.7 pg/mL, and 4.5-13.8 pg/ mL, respectively. CONCLUSION Reference ranges of serum T-T and F-T in Japanese male adults have established. And the value of Young Adult Mean (YAM) of F-T calculated for a group of the ages between 20 and 39 years have been proposed as a guideline of requirement for the Androgen Replacement Therapy (HRT). The value of 80% and 70% of YAM were 12.4 pg/mL and 10.9 pg/mL, respectively.
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Chu S, Nishi Y, Yanase T, Nawata H, Fuller PJ. Transrepression of Estrogen Receptor β Signaling by Nuclear Factor-κB in Ovarian Granulosa Cells. Mol Endocrinol 2004; 18:1919-28. [PMID: 15155785 DOI: 10.1210/me.2004-0021] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Estrogen receptor (ER) beta is the predominant ER in granulosa cells of the ovary. ERbeta is expressed at high levels in granulosa cell tumors (GCT) and in the human GCT-derived cell lines, COV434 and KGN. To gain insight into ERbeta function in granulosa cells and in GCT, we have used the COV434 and KGN cell lines. Although the cells bind estradiol (E2), transcriptional activation of a transfected estrogen-responsive reporter vector construct (ERE2-luc) by E2 was not observed. Transactivation was also not observed with cotransfected ERalpha or beta. This transcriptional resistance is specific to steroid receptor transactivation; reporter plasmids that are activated by the transcription factors activator protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) demonstrate both constitutive and inducible transactivation. AP-1 and NF-kappaB are known to cause transrepression of both ERalpha- and glucocorticoid receptor-mediated transcription. We therefore examined the possibility that activation of these pathways was responsible for the lack of a response to estrogen by using inhibitors of AP-1 or NF-kappaB. The AP-1 inhibitors alone had no effect, whereas inhibition of NF-kappaB signaling allowed a 3- to 4-fold E2-mediated induction of ERE2-luc. This response was both ligand and ER dependent. Repression of ERbeta signaling by NF-kappaB has not previously been reported. Recent evidence suggests that ERbeta may function to promote differentiation. The inhibition of ERbeta in combination with the antiapoptotic properties of NF-kappaB may therefore contribute to pathogenesis of GCT.
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Liu W, Fan WQ, Yanase T, Saitoh M, Wu Y. Activation of protein kinase A alters subnuclear distribution pattern of human steroidogenic factor 1 in living cells. Chin Med J (Engl) 2004; 117:1017-22. [PMID: 15265375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
BACKGROUND The aim of this study was to identify the subnuclear distribution pattern of human orphan nuclear receptor steroidogenic factor 1 (SF-1) in living cells with and without the activation of protein kinase A (PKA) signal pathway, and thus try to explain the unknown mechanism by which PKA potentiates SF-1 transactivation. METHODS Full-length cDNAs of wild type and a naturally occurring mutant (G35E) human SF-1 were cloned and fused with green fluorescent protein (GFP). Subcellular distribution pattern of human SF-1 in living cells, whose PKA signaling was either activated or not, was studied by laser confocal microscopy after the validity of the gene sequence was confirmed. RESULTS The transactivation ability of the GFP-SF-1 chimeric protein was highly conserved. Wild type human SF-1 diffused homogeneously within the nuclei of cells when PKA was not active, and converged to clear foci when PKA was activated. Mutant SF-1 diffused within the nuclei even in the presence of PKA activation, surprisingly aggregating as fluorescent dots inside the nucleoli, a phenomenon not altered by PKA. CONCLUSIONS Activation of PKA causes wild type, but not mutant SF-1 to alter its subnuclear distribution pattern to a transactivationally active form (foci formation). This finding may throw new light on the mechanism by which PKA activates the orphan nuclear receptor.
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Yanase T, Fukutomi T, Yoshida K, Kato T, Ohashi S, Yamakawa M, Tsuda T. The emergence in Japan of Sathuperi virus , a tropical Simbu serogroup virus of the genus Orthobunyavirus. Arch Virol 2004; 149:1007-13. [PMID: 15098114 DOI: 10.1007/s00705-003-0266-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Accepted: 10/27/2003] [Indexed: 10/26/2022]
Abstract
In 1999, two viruses were isolated from blood samples of sentinel cattle in the Western part of Japan. The physiochemical and morphological properties of these viruses indicated that they belonged to the family Bunyaviridae. Sequence analysis of the S segment indicates that the two viruses are closely related to Sathuperi virus (SATV). The N-terminal 168 amino acid of the G2 protein of the M segment was highly homologous with that of SATV (98.2%). Given these results, we conclude that the newly isolated viruses are closest to SATV, which was initially isolated in India and Nigeria over 30 years ago.
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Abstract
Coregulators are a group of proteins, which modulate the nuclear receptor transactivation function. In this study, a new "coregulator disease" concept was proposed from observations of a case of androgen insensitivity syndrome (AIS) and cases involving Rubinstein-Taybi syndrome and X-linked dementia and hypothyroidism syndrome. In addition, coregulators are thought to be closely associated with the pathogenesis of several diseases such as hormone-dependent cancers and leukemia. Based on these observations, the clinical disorders associated with some coregulator abnormalities were reviewed.
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Morinaga H, Yanase T, Nomura M, Okabe T, Goto K, Harada N, Nawata H. A benzimidazole fungicide, benomyl, and its metabolite, carbendazim, induce aromatase activity in a human ovarian granulose-like tumor cell line (KGN). Endocrinology 2004; 145:1860-9. [PMID: 14691014 DOI: 10.1210/en.2003-1182] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endocrine disruptor chemicals are known to cause a range of abnormalities in sexual differentiation and reproduction. One mechanism underlying such effects may be via alteration of aromatase activity, which is responsible for estrogen production. A good screening system for identifying endocrine disruptors has long been desired. We have recently established a human ovarian granulosa-like tumor cell line, KGN, which possesses a relatively high level of aromatase expression and is considered a useful mammalian model for investigating the in vitro effects of various chemicals on aromatase activity. In this study we screened 55 different candidate chemicals for endocrine disruptors by assaying aromatase activity. Only benomyl, known as both a benzimidazole fungicide and a microtubule-interfering agent, was found to induce aromatase activity in association with increased levels of aromatase mRNA in KGN cells. The effect of benomyl was presumed to be mediated by its metabolite carbendazim, because it produced an effect equivalent to that of benomyl. The mechanism underlying the benomyl-induced increase in aromatase activity appears independent of the cAMP-protein kinase A pathway. Treatment with taxol, another class of microtubule-interfering agents, also caused induction of aromatase in KGN cells. Both benomyl and taxol changed KGN cell morphology, including the development of cell roundness and a disorganized network of microtubules. These results indicate that benomyl is a potential endocrine disruptor that provides a novel estrogenicity and operates through a microtubule-interfering mechanism.
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Yanase T. [Hypertension secondary to adrenal steroidogenic enzyme deficiency]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2004; 62 Suppl 3:531-5. [PMID: 15171430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Mu YM, Oba K, Yanase T, Ito T, Ashida K, Goto K, Morinaga H, Ikuyama S, Takayanagi R, Nawata H. Human pituitary tumor transforming gene (hPTTG) inhibits human lung cancer A549 cell growth through activation of p21(WAF1/CIP1 ). Endocr J 2003; 50:771-81. [PMID: 14709851 DOI: 10.1507/endocrj.50.771] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Pituitary tumor transforming gene (PTTG) is a proto-oncogene cloned from rat GH4 cells. This gene was able to induce cell transformation in vitro and is also associated with p53-dependent and -independent apoptosis. In this study, we cloned human PTTG (hPTTG) from a pituitary tumor and then stably transfected the hPTTG into HeLa and A549 cells. An overexpression of hPTTG significantly inhibited cell growth, which was determined by the adherent cell growth properties, colony formation in soft agar and [3H] thymidine incorporation, respectively, in HeLa and A549 cells. The inhibitory effect on cell growth was associated with the activation of p21WAF1/CIP1 in A549 cells, but not in HeLa cells. The hPTTG overexpression increased both the p21WAF1/CIP1 mRNA and protein expression levels as determined by both Northern and Western blot analysis, respectively, in A549 cells. The increased expression of p21WAF1/CIP1 mRNA was regulated at the transcription level and was independent on p53 expression because the luciferase activity increased after the co-transfection of hPTTG and p21WAF1/CIP1 promoter fragments with and without a p53 binding sequence. The subcellular distribution of hPTTG was dependent on cell type, and was predominantly in the nucleus in HeLa, Cos-7 and DU145 cells, but showed a diffuse distribution in both the nucleus and cytoplasm in A549, DLD-1 and NIH3T3 cells. These results indicate that an overexpression of hPTTG inhibits the cell growth due to different mechanisms, which are p21WAF1/CIP1 -dependent and -independent.
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WuQiang F, Yanase T, Wei L, Oba K, Nomura M, Okabe T, Goto K, Nawata H. Functional characterization of a new human Ad4BP/SF-1 variation, G146A. Biochem Biophys Res Commun 2003; 311:987-94. [PMID: 14623279 DOI: 10.1016/j.bbrc.2003.10.096] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ad4BP/SF-1 plays key roles at all levels of the hypothalamic-pituitary-steroidogenic organ axis and its functional disruption causes endocrine disorders of these organs. However, only three human subjects with Ad4BP/SF-1 mutations have been reported to date, suggesting limited clinical significance as a cause of inborn adrenal or sexual abnormalities. We report the first functional characterization of a new variation found in the hinge region of human Ad4BP/SF-1, G146A. Resulting from a single nucleotide shift (GGG-->GCG), G146A bears slightly diminished transactivation activity evidenced by both adrenal specific cyp11A promoter and ovary specific cyp19 promoter II. The variation does not affect protein expression or stability, exhibiting no dominant negative effect. G146A has a normal interaction pattern with standard co-regulators and subnuclear distribution pattern, and can be considered as a nonsynonymous single nucleotide polymorphism, since it occurs in normals and patients with adrenal diseases. In normal Japanese the allele C frequency is 8%, while in a preliminary population of patients with adrenal diseases it is elevated to 30%; suggesting the G146A variation might be of clinical importance.
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Yanase T, Suzuki S, Goto K, Nawata H, Takayanagi R. [DHEA and bone metabolism]. CLINICAL CALCIUM 2003; 13:1419-1424. [PMID: 15775227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A strong positive correlation of serum dehydroepiandrosterone sulfate (DHEA-S) and estrone (E1) with bone mineral density (BMD) in postmenopausal women but no correlation between serum estradiol (E2) and BMD in the same group suggest that circulating adrenal androgen may be converted to estrogen in peripheral tissues including osteoblast and may contribute to BMD maintenance. Actually, in cultured human osteoblast cells, DHEA can be converted to androstenedione and then androstenedione to estrone through the apparent aromatase activity. In human bone cells, intracrine mechanism through aromatase activity may contribute to the local production of estrogens, thus leading to protective effect against osteoporosis especially after menopause.
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214
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Fan W, Yanase T, Wu Y, Kawate H, Saitoh M, Oba K, Nomura M, Okabe T, Goto K, Yanagisawa J, Kato S, Takayanagi R, Nawata H. Protein kinase A potentiates adrenal 4 binding protein/steroidogenic factor 1 transactivation by reintegrating the subcellular dynamic interactions of the nuclear receptor with its cofactors, general control nonderepressed-5/transformation/transcription domain-associated protein, and suppressor, dosage-sensitive sex reversal-1: a laser confocal imaging study in living KGN cells. Mol Endocrinol 2003; 18:127-41. [PMID: 14555713 DOI: 10.1210/me.2003-0110] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The mechanism through which protein kinase A (PKA) potentiates the transactivation ability of adrenal 4 binding protein/steroidogenic factor 1 (Ad4BP/SF-1) is currently unclear. In the present study, we investigated the mechanism by applying laser confocal microscopy and fluorescence recovery after photobleaching technique. In KGN cells, forskolin (a PKA stimulator) could reorganize wild-type Ad4BP/SF-1, but not mutant Ad4BP/SF-1 (G35E), from a diffuse distribution pattern to foci formation in the nucleus. The subcellular distributions of GCN5 (general control nonderepressed) and TRRAP (transformation/transcription domain-associated protein), both of which were recently proved to be working in the same complex as the third class of nuclear receptor coactivators, were unexpectedly diffuse inside and outside the nucleus, respectively, when they were separately transfected. However TRRAP was translocated into the nucleus in the presence of GCN5, and together with GCN5 colocalized with Ad4BP/SF-1 in the same foci when PKA was activated. A luciferase assay also indicated that these two cofactors enhanced Ad4BP/SF-1 transactivation.Dosage-sensitive sex reversal (DAX-1) interacts with and thus inhibits Ad4BP/SF-1 transactivation. The coexistence of the two proteins dramatically altered their respective subnuclear distributions. They colocalized extensively, suggestive of binding, and Ad4BP/SF-1 was sharply immobilized when DAX-1 was coexpressed, whereas PKA could maintain mobility, as evidenced by Fluorescence Recovery After Photobleaching showing that Ad4BP/SF-1 mobility recovered after forskolin treatment.Therefore, the PKA signal pathway may modify the interaction between Ad4BP/SF-1 and its activators and repressor (GCN5 and TRRAP are integrated, whereas DAX-1 is disassociated), and thus stimulate the Ad4BP/SF-1 transactivation.
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Yanase T. [Clinical significance of dehydroepiandrosterone (DHEA) supplement therapy]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2003; 92:1701-4. [PMID: 14560605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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216
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Yanase T, Suzuki S, Goto K, Nomura M, Okabe T, Takayanagi R, Nawata H. Aromatase in bone: roles of Vitamin D3 and androgens. J Steroid Biochem Mol Biol 2003; 86:393-7. [PMID: 14623536 DOI: 10.1016/s0960-0760(03)00349-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We have mainly focused on the regulatory mechanism of cytochrome P450 aromatize in bone cells. Our previous study demonstrated a strong positive correlation of serum dehydroepiandrosterone sulfate (DHEA-S) and estrone (E1) with BMD in postmenopausal women but no correlation between serum estradiol (E2) and BMD in the same group. In addition, administration of DHEA to ovariectomized rat significantly increased BMD. These in vivo findings strongly suggested that circulating adrenal androgen may be converted to estrogen in osteoblast and may contribute to BMD maintenance. Actually, in cultured human osteoblast cells, DHEA was found to convert to androstenedione by 3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity and then androstenedione to estrone through the apparent aromatase activity. The aromatase activity in cultured human osteoblast cells was significantly increased by dexamethasone (DEX). Interestingly, DEX and 1alpha,25-dihydroxyvitamin D3 (VD3) synergistically enhanced aromatase activity as well as P450arom mRNA expression. A little stronger induction of aromatase activity by DEX and VD3 was observed in cultured human fibroblasts. The increase of the aromatase activity by DEX and VD3 was accompanied with the increase of luciferase activity of fibroblast cells transfected with Exon 1b-promoter-luciferase construct, but not of osteoblasts transfected with the same construct, suggesting a different regulatory mechanism of aromatase by DEX and 1alpha,25-dihydroxyvitamin D3 (VD3) between these two cells despite the same promotor usage. In human bone cells, intracrine mechanism through aromatase activity, together with a positive regulation of aromatase activity by glucocorticoid and VD3, may contribute to the local production of estrogens, thus leading to protective effect against osteoporosis especially after menopause. The effect of sex steroids (estrogen versus testosterone) in bone remodeling was also briefly reviewed based on several recent findings in this field.
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Goto K, Zhao Y, Saito M, Tomura A, Morinaga H, Nomura M, Okabe T, Yanase T, Takayanagi R, Nawata H. Activation function-1 domain of androgen receptor contributes to the interaction between two distinct subnuclear compartments. J Steroid Biochem Mol Biol 2003; 85:201-8. [PMID: 12943705 DOI: 10.1016/s0960-0760(03)00196-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The nucleus contains different sets of functional compartments often called "speckles". The splicing factor compartment (SFC) has been speculated to consist of SFs and transcription factors, which thus make transcription-splicing coupling possible at the periphery of SFC. Androgen receptor (AR), as well as glucocorticoid receptor (GR), is unique since most, if not all, of its activities are mediated via the constitutive activity of the activation function-1 (AF-1) function. Transcriptionally active AR produces 250-400 subnuclear fine speckles11 shared with GR or estrogen receptor (ER), which colocalize with chiefly activation function-2 (AF-2)-interacting p160 family- or CBP-related speckles. We herein report the isolation of ANT-1 (AR N-terminal domain (NTD) transactivating protein-1) enhancing autonomous AF-1 transactivation function of AR or GR, but not of estrogen receptor alpha (ERalpha). The ANT-1 was identical to a binding protein of human splicing factor U5 snRNP (U5 snRNP-associated protein). ANT-1 was compartmentalized into 15-20 coarse SFC speckles which were spatially distinct from but surrounded by the AR compartments. Our results suggest that ANT-1 may play a key role in the molecular interaction between two spatially distinct subnuclear compartments in a receptor-specific fashion, and thereby induce the strong autonomous transactivation functions either of AR- or GR-AF-1.
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218
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Lu ZH, Mu YM, Wang BA, Li XL, Lu JM, Li JY, Pan CY, Yanase T, Nawata H. Saturated free fatty acids, palmitic acid and stearic acid, induce apoptosis by stimulation of ceramide generation in rat testicular Leydig cell. Biochem Biophys Res Commun 2003; 303:1002-7. [PMID: 12684033 DOI: 10.1016/s0006-291x(03)00449-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In men, obesity has generally been associated with reduced plasma testosterone levels and with elevation of the plasma free fatty acids (FFAs). In this study, we investigated the effects of saturated FFAs including palmitic acid (PA) and stearic acid (SA), and polyunsaturated FFA arachidonic acid (AA) on the survival of rat testicular Leydig cell cultured in vitro. PA and SA markedly suppressed Leydig cell survival in a time- and dose-dependent manner. In contrast, AA stimulated the cell proliferation at 5-10 times of physiological concentration. The suppressive effect of PA and SA on cell survival was caused by apoptosis evidenced by DNA ladder formation and Annexin V-EGFP/propidium iodide staining of the cells. The apoptotic effect of PA was possibly mediated by ceramide generation because it could be completely blocked by ceramide synthase inhibitor fumonisin B1 and exogenous ceramide itself could directly induce apoptosis in vitro. Surprisingly, the apoptosis induced by PA could be partly prevented by AA. These results indicate that PA and SA induce apoptosis in testicular Leydig cells by ceramide production and these apoptotic effects may be a possible mechanism for reproductive abnormalities in obese men, and AA can partly prevent the apoptotic effect induced by saturated FFA.
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Mukasa C, Nomura M, Tanaka T, Tanaka K, Nishi Y, Okabe T, Goto K, Yanase T, Nawata H. Activin signaling through type IB activin receptor stimulates aromatase activity in the ovarian granulosa cell-like human granulosa (KGN) cells. Endocrinology 2003; 144:1603-11. [PMID: 12639945 DOI: 10.1210/en.2002-220978] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In addition to a stimulatory effect on FSH production by the pituitary gland, activin is thought to have a paracrine or autocrine role in follicular development in the ovary, where it is produced. Recently, we established a human ovarian granulosa tumor cell line, KGN, which possesses in vivo characteristics of granulosa cells, namely the expression of functional FSH receptors and cytochrome P-450 aromatase. Here, we have demonstrated the activin signaling pathway and its role in KGN cells. A series of transient transfection experiments revealed that activin type IB receptor (ActRIB) is an essential component of the activin signaling pathway in KGN cells. Smad2 was found to act downstream of ActRIB as an intracellular signal transmitter. Smad7, but not Smad6, was an inhibitory Smad in the pathway. Finally, we show that FSH receptor expression and cytochrome P-450 (P-450) aromatase activity was up-regulated by activin stimulation through ActRIB in KGN cells. These results show that we have clarified the signaling mechanisms and the roles of activin in the human granulosa cell line, KGN. Activin signaling mediated by ActRIB-Smad2 system in the ovary may thus be essential for the regulation of follicular differentiation.
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Yanase T, Gondo S, Okabe T, Nawata H. [Trials of regeneration and gene therapies in endocrine organs, especially in adrenal glands]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2003; 61:509-14. [PMID: 12701182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Recent progress in trials of regeneration and gene therapy in endocrine organs, especially in adrenal glands has been reviewed. Gene therapies using adenovirus have been most frequently tested in vivo and in vitro, aiming at improvement of steroidogenesis and suppression of adrenal tumor growth. Although the effects were temporal, promising results have been obtained. Interestingly, adrenocortical tissue was shown to be formed by transplantation of adrenocortical cells and to replace the adrenal functions of adrenalectomized animals. Engineered ES cells stably expressing Ad4BP/SF-1 were shown to be directed toward steroidogenic lineage, suggesting a future possibility of regeneration of adrenal cells.
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Yanase T, Adachi M, Takayanagi R, Nawata H. [Cofactor diseases]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2003; 92:324-9. [PMID: 12652740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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Fujii A, Harada T, Yamauchi N, Iwabe T, Nishi Y, Yanase T, Nawata H, Terakawa N. Interleukin-8 gene and protein expression are up-regulated by interleukin-1beta in normal human ovarian cells and a granulosa tumor cell line. Fertil Steril 2003; 79:151-7. [PMID: 12524080 DOI: 10.1016/s0015-0282(02)04408-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To evaluate the expression, regulation, and role of interleukin (IL)-8 in human ovary. DESIGN Prospective study. SETTING University hospital. PATIENT(S) Sixteen premenopausal women. INTERVENTION Follicular fluid and granulosa lutein cells (GLCs) were collected during IVF cycles. Ovarian stromal and theca cells were obtained from women underwent surgery. KGN cells, the human granulosa cell tumor cell line, were also used. MAIN OUTCOME MEASURES The levels of IL-8 and IL-1beta in follicular fluid and IL-8 protein production were determined using ELISA. Interleukin-8 and IL-8 receptor gene expression in ovarian cells and the effect of IL-8 on the proliferation of stromal cells were determined. The expression of pIkappaB was evaluated by Western blot, and the effect of NF-kappaB inhibitor APDC was examined by Northern blot analysis and ELISA in KGN cells. The levels of IL-8 and IL-1beta in follicular fluid; each concentration and the volume showed a positive correlation. Reverse transcription polymerase chain reaction showed the presence of IL-8 mRNA in all ovarian cells. In contrast, IL-8 receptor mRNA was only detected in stromal cells. The expression of IL-8 in GLCs and KGN cells was increased by addition of IL-1beta and TNFalpha. Interleukin-8 increased the proliferation of ovarian stromal cells. The expression of pIkappaB in KGN cells was induced by IL-1beta, and the effects were reduced by APDC. CONCLUSION(S) Interleukin 8 induced by IL-1beta via activation of NF-kappaB in granulosa cells may have a role in the periovulatory period of follicular maturation.
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Zhao Y, Goto K, Saitoh M, Yanase T, Nomura M, Okabe T, Takayanagi R, Nawata H. Activation function-1 domain of androgen receptor contributes to the interaction between subnuclear splicing factor compartment and nuclear receptor compartment. Identification of the p102 U5 small nuclear ribonucleoprotein particle-binding protein as a coactivator for the receptor. J Biol Chem 2002; 277:30031-9. [PMID: 12039962 DOI: 10.1074/jbc.m203811200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the androgen receptor (AR), most of its transactivation activity is mediated via the activation function-1 (AF-1). By employing yeast two-hybrid assay, we isolated a cDNA sequence encoding a protein binding to AR-AF-1. This protein, named ANT-1 (AR N-terminal domain transactivating protein-1), enhanced the ligand-independent autonomous AF-1 transactivation function of AR or glucocorticoid receptor but did not enhance that of estrogen receptor alpha. In contrast, the ANT-1 did not enhance any ligand-dependent AF-2 activities. Furthermore, the ligand-independent interaction between AR-AF-1 and ANT-1 was confirmed in vivo and in vitro. The ANT-1 sequence was identical to that of a protein that binds to U5 small nuclear ribonucleoprotein particle, a human homologue of yeast splicing factor Prp6p, involved in spliceosome. ANT-1 was compartmentalized into 20-40 coarse splicing factor compartment speckles against the background of the diffuse reticular distribution. AR colocalized with ANT-1 only in the diffusely distributed area, whereas the ANT-1 speckles were spatially distinct from but surrounded by the AR compartments. The active gene transcription has been shown to couple simultaneously with pre-mRNA processing at the periphery of the splicing factor compartment. The molecular interaction between two spatially distinct subnuclear compartments mediated by ANT-1 may therefore recruit AR into the transcription-splicing-coupling machinery.
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Katafuchi R, Masutani K, Mizumasa T, Fujita E, Tanaka H, Ikeda K, Yanase T, Ando T, Fujimi S. A case of persistent acute allograft glomerulopathy with long-standing stable renal function. Clin Transplant 2002; 15 Suppl 5:2-10. [PMID: 11791790 DOI: 10.1034/j.1399-0012.2001.0150s5002.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Acute allograft glomerulopathy (AAG) characterized by hypercellularity, enlargement of endothelial cells, infiltration of glomeruli by mononuclear cells and webs of PAS-positive material has been reported as an unusual but distinct form of acute rejection in kidney transplant recipients. We present a case of persistent AAG proven by serial biopsies. The patient was 53 years old when she received kidney transplantation from her mother. The immunosuppressants were methylprednisolone, azathioprine and FK506. She developed several acute rejections and received antirejection therapy. The patient transferred to our hospital 15 months after transplantation. Serum creatinine was 2.11 mg/dL. The level of serum creatinine was gradually elevated from 2.11 mg/dL to 3.09 mg/dL. Graft biopsy, performed 16.5 months after transplantation, represented prominent intraglomerular infiltration of mononuclear cells, segmental thickening of glomerular basement membrane (GBM) with double contour, grade 1 tubulitis, marked accumulation of mononuclear cells in peritubular capillaries and margination of mononuclear cells in a small artery. It was diagnosed as acute allograft glomerulopathy (AAG). Intravenous methylprednisolone pulse therapy, discontinuation of FK506 and administration of cyclosporin (CYA) resulted in decrease of serum creatinine. To evaluate histological evolution of AAG we performed two subsequent biopsies over 3 yr. Severe glomerulitis persisted as a prominent feature 8 months later and still existed 53.4 months after transplantation with decreased severity. The extent of GBM reduplication also decreased, but the percentage of glomerular sclerosis increased gradually. Multi-layering of basement membrane of peritubular capillary and interstitial fibrosis also increased. The prominence of infiltration of mononuclear cells in peritubular capillary was unchanged. At the last follow-up, i.e. 71 months after transplantation, her serum creatinine was 1.34 mg/dL. Neither proteinuria nor haematuria was observed. We consider that our immunosuppressive treatment has been successful so far, because the patient is still maintaining stable graft function since the transplantation over 6 yr ago. It is thus suggested that AAG per se probably has no influence on acute aggravation of graft function, but AAG and capillaritis in peritubular capillaries may cause an evolution of chronic allograft nephropathy, resulting in a slowly progressive deterioration of graft function.
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Nawata H, Yanase T, Goto K, Okabe T, Ashida K. Mechanism of action of anti-aging DHEA-S and the replacement of DHEA-S. Mech Ageing Dev 2002; 123:1101-6. [PMID: 12044959 DOI: 10.1016/s0047-6374(01)00393-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The plasma ACTH and cortisol levels do not change during aging. On the other hand, the plasma dehydroepiandrosterone sulfate (DHEA-S) changes remarkably during aging. Before puberty, the plasma DHEA-S level both in males and females is very low, however, it rapidly increases at puberty, and thereafter significantly decreases both linearly and age-dependently. Cytochrome P450c17 has two enzyme activities, 17-alpha-hydroxylase and 17,20-lyase. Cortisol is synthesized by 17-alpha-hydroxylase, and DHEA is synthesized by 17,20-lyase. The mechanism of dissociation of cortisol and DHEA synthesis in aging depends on another regulator of 17,20-lyase of cytochrome P450c17 such as cytochrome P450 reductase. We demonstrated significant decrease in cytochrome P450 reductase activity in bovine aged adrenal glands. We clarified the beneficial effects of DHEA as an anti-aging steroid based on both in vitro and in vivo experiments, such as the stimulatory effect of immune system, anti-diabetes mellitus, anti-atherosclerosis, anti-dementia (neurosteroid), anti-obesity and anti-osteoporosis. It is very important to identify the mechanism of action of DHEA. We clarified the conversion of DHEA to estrone by cytochrome P450 aromatase in primary cultured human osteoblasts. We indentified high affinity of DHEA binding with K(d)=6.6 nM in antigen and DHEA stimulated human T lymphocytes. We searched for the target genes that are specifically induced in activated T lymphocytes in the presence of DHEA by subtractive hybridization screening for differentially expressed transcripts. The double blind, randomized human replacement therapies utilizing DHEA are also reviewed.
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